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Find video protocols related to scientific articles indexed in Pubmed.
Encoding high-order cylindrically polarized light beams.
Appl Opt
PUBLISHED: 10-17-2014
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In this work we present a setup for the experimental production of cylindrically polarized beams, as well as other variations of polarized light beams. The optical system uses a single transmissive phase-only spatial light modulator, which is used to apply different spatial phase modulation to two output collinear R and L circularly polarized components. Different cylindrically polarized light beams can be obtained by applying different phase shifts to these two circularly polarized components. The system is very efficient since modulation is directly applied to the light beam (as opposed to other common methods operating in the first order of encoded diffraction gratings). Different variations to the cylindrically polarized light beams are also reported, obtained by adding linear or quadratic relative phase shifts between the two circular polarization components of the light beam. Experimental results are provided in all cases.
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Solution mechanism guide: implementing innovation within a research & development organization.
Aviat Space Environ Med
PUBLISHED: 09-24-2014
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In order to create a culture more open to novel problem-solving mechanisms, NASA's Human Health and Performance Directorate (HH&P) created a strategic knowledge management tool that educates employees about innovative problem-solving techniques, the Solution Mechanism Guide (SMG). The SMG is a web-based, interactive guide that leverages existing and innovative problem-solving methods and presents this information as a unique user experience so that the employee is empowered to make the best decision about which problem-solving tool best meets their needs. By integrating new and innovative methods with existing problem solving tools, the SMG seamlessly introduces open innovation and collaboration concepts within HH&P to more effectively address human health and performance risks. This commentary reviews the path of creating a more open and innovative culture within HH&P and the process and development steps that were taken to develop the SMG.
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Evaluation of the effect of multiple doses of lansoprazole on the pharmacokinetics and safety of ponatinib in healthy subjects.
Clin Drug Investig
PUBLISHED: 08-23-2014
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In vitro studies have demonstrated that the aqueous solubility of the tyrosine kinase inhibitor ponatinib decreases as pH increases.
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The Wisconsin immunization registry experience: comparing real-time and batched file submissions from health care providers.
WMJ
PUBLISHED: 08-15-2014
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The Wisconsin Immunization Registry is a confidential, web-based system used since 1999 as a centralized repository of immunization information for Wisconsin residents.
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Transplantation outcomes for severe combined immunodeficiency, 2000-2009.
N. Engl. J. Med.
PUBLISHED: 07-31-2014
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The Primary Immune Deficiency Treatment Consortium was formed to analyze the results of hematopoietic-cell transplantation in children with severe combined immunodeficiency (SCID) and other primary immunodeficiencies. Factors associated with a good transplantation outcome need to be identified in order to design safer and more effective curative therapy, particularly for children with SCID diagnosed at birth.
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An investigation of antibiotic susceptibility to empiric therapy for community-associated methicillin-resistant Staphylococcus aureus.
WMJ
PUBLISHED: 06-10-2014
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To analyze antibiotic susceptibility patterns of community-associated methicillin-resistant Staphylococcus aureus (MRSA) isolates obtained from skin and soft tissue infections among Wisconsin outpatients.
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Estimating the effectiveness of tetanus-diphtheria-acellular pertussis vaccine (Tdap) for preventing pertussis: evidence of rapidly waning immunity and difference in effectiveness by Tdap brand.
J. Infect. Dis.
PUBLISHED: 06-05-2014
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We estimated the vaccine effectiveness (VE) of tetanus-diphtheria-acellular pertussis vaccine (Tdap) for preventing pertussis among adolescents during a statewide outbreak of pertussis in Wisconsin during 2012.
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Multistate outbreak of Salmonella enterica serotype enteritidis infection associated with pet guinea pigs.
Vector Borne Zoonotic Dis.
PUBLISHED: 05-27-2014
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Salmonella causes about one million illnesses annually in the United States. Although most infections result from foodborne exposures, animal contact is an important mode of transmission. We investigated a case of Salmonella enterica serotype Enteritidis (SE) sternal osteomyelitis in a previously healthy child who cared for two recently deceased guinea pigs (GPs). A case was defined as SE pulsed-field gel electrophoresis (PFGE) XbaI pattern JEGX01.0021, BlnI pattern JEGA26.0002 (outbreak strain) infection occurring during 2010 in a patient who reported GP exposure. To locate outbreak strain isolates, PulseNet and the US Department of Agriculture National Veterinary Service Laboratories (NVSL) databases were queried. Outbreak strain isolates underwent multilocus variable-number tandem repeat analysis (MLVA). Traceback and environmental investigations were conducted at homes, stores, and breeder or broker facilities. We detected 10 cases among residents of eight states and four NVSL GP outbreak strain isolates. One patient was hospitalized; none died. The median patient age was 9.5 (range, 1-61) years. Among 10 patients, two purchased GPs at independent stores, and three purchased GPs at different national retail chain (chain A) store locations; three were chain A employees and two reported GP exposures of unknown characterization. MLVA revealed four related patterns. Tracebacks identified four distributors and 92 sources supplying GPs to chain A, including one breeder potentially supplying GPs to all case-associated chain A stores. All environmental samples were Salmonella culture-negative. A definitive SE-contaminated environmental source was not identified. Because GPs can harbor Salmonella, consumers and pet industry personnel should be educated regarding risks.
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Evaluation of pharmacokinetics and safety of ponatinib in subjects with chronic hepatic impairment and matched healthy subjects.
Cancer Chemother. Pharmacol.
PUBLISHED: 05-15-2014
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This study evaluated the effects of chronic hepatic impairment on the single-dose pharmacokinetics (PK) of the tyrosine kinase inhibitor ponatinib.
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Outcomes after hematopoietic stem cell transplantation for children with I-cell disease.
Biol. Blood Marrow Transplant.
PUBLISHED: 05-13-2014
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Mucolipidosis type II (MLII), or I-cell disease, is a rare but severe disorder affecting localization of enzymes to the lysosome, generally resulting in death before the 10th birthday. Although hematopoietic stem cell transplantation (HSCT) has been used to successfully treat some lysosomal storage diseases, only 2 cases have been reported on the use of HSCT to treat MLII. For the first time, we describe the combined international experience in the use of HSCT for MLII in 22 patients. Although 95% of the patients engrafted, overall survival was low, with only 6 patients (27%) alive at last follow-up. The most common cause of death post-transplant was cardiovascular complications, most likely due to disease progression. Survivors were globally delayed in development and often required complex medical support, such as gastrostomy tubes for nutrition and tracheostomy with mechanical ventilation. Although HSCT has demonstrated efficacy in treating some lysosomal storage disorders, the neurologic outcome and survival for patents with MLII were poor. Therefore, new medical and cellular therapies should be sought for these patients.
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Analysis of the propagation dynamics and Gouy phase of Airy beams using the fast Fresnel transform algorithm.
Appl Opt
PUBLISHED: 05-03-2014
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There is great interest in Airy beams because they appear to propagate in a curved path. These beams are usually generated by inserting a cubic phase mask onto the input plane of a Fourier transform system. Here, we utilize a fast Fresnel diffraction algorithm to easily derive both the propagation dynamics and the Gouy phase shift for these beams. The trajectories of these beams can be modified by adding additional linear and quadratic phase terms onto the cubic phase mask. Finally, we have rewritten the equations regarding the propagating Airy beams completely in laboratory coordinates for use by experimentalists. Experimental results are included. We expect that these results will be of great importance in applications of Airy beams.
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Arithmetic of focused vortex beams in three-dimensional optical lattice arrays.
Appl Opt
PUBLISHED: 05-03-2014
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In this work, we present a method to generate a 3D lattice of vortex beams. We apply phase look-up tables (LUTs) designed to generate gratings having an arbitrary content of diffraction orders. This phase LUT can be applied to a variety of diffraction optical elements, such as linear phase gratings, blazed diffractive lenses, and spiral phase patterns. We concentrate on combinations of all of these to create 3D structures of vortex beams. In particular, we generate all of these elements in the first output quadrant and eliminate the zero-order diffraction that often unavoidably accompanies these patterns. We discuss different ways of producing these 3D vortex gratings, and how the various output beams are related to the arithmetic of the 3D distribution of topological charges. Experimental results are provided by means of a liquid crystal spatial light modulator.
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Rapid hepatitis C testing among persons at increased risk for infection--Wisconsin, 2012-2013.
MMWR Morb. Mortal. Wkly. Rep.
PUBLISHED: 04-11-2014
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An estimated 3.2 million persons in the United States have chronic infection with hepatitis C virus (HCV). Most new HCV transmissions occur among persons who inject drugs, often within the first few years of their injection drug use. During 2003-2012, reports of HCV infection increased from 15 to 54 cases per 100,000 among persons aged <30 years in Wisconsin, and 58% of persons in this age group with acute HCV infection reported injecting drugs (Wisconsin Division of Public Health, unpublished data, 2013). To increase detection of HCV infection, the Wisconsin Division of Public Health (WDPH) piloted a program during October 2012-October 2013 that offered rapid HCV testing to clients of four agencies providing outreach testing for HCV and human immunodeficiency virus infection, syringe exchange, counseling, and other harm reduction services to persons with drug dependence. During that period, 1,255 persons were tested using a rapid HCV test, and 246 (20%) of the results were positive. Most (72%) of the infections had not been reported to WDPH. A blood specimen for further testing was collected from 192 (78%) participants with positive HCV test results; among these participants, 183 were tested for HCV RNA using reverse transcription-polymerase chain reaction (RT-PCR), and these results were positive for 128 (70%) participants, indicating active infection. Use of the rapid HCV test detected previously unreported HCV infections and raised awareness of HCV. Persons identified with active HCV infection should be referred to medical care and counseled on ways to prevent HCV transmission to others.
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Confocal microscopy of cardiac myocytes.
Methods Mol. Biol.
PUBLISHED: 04-08-2014
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Detailed methods are provided for the preparation and confocal imaging of cardiac myocyte development and differentiation. Examples include protocols for the analysis of cultured myocytes as well as vibratome sections of hearts from embryonic and adult tissue. Techniques include routine labeling of F-actin with phalloidin as well as multiple labeling protocols for colocalization studies and cell volume analysis.
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Isolating quantum coherence using coherent multi-dimensional spectroscopy with spectrally shaped pulses.
Opt Express
PUBLISHED: 03-26-2014
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We demonstrate how spectral shaping in coherent multidimensional spectroscopy can isolate specific signal pathways and directly access quantitative details. By selectively exciting pathways involving a coherent superposition of exciton states we are able to identify, isolate and analyse weak coherent coupling between spatially separated excitons in an asymmetric double quantum well. Analysis of the isolated signal elucidates details of the coherent interactions between the spatially separated excitons. With a dynamic range exceeding 10(4) in electric field amplitude, this approach facilitates quantitative comparisons of different signal pathways and a comprehensive description of the electronic states and their interactions.
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Accelerating light beams with arbitrarily transverse shapes.
Opt Express
PUBLISHED: 03-26-2014
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Accelerating beams are wave packets that preserve their shape while propagating along curved trajectories. Their unique characteristics have opened the door to applications that range from optical micromanipulation and plasma-channel generation to laser micromachining. Here, we demonstrate, theoretically and experimentally, that accelerating beams can be generated with a variety of arbitrarily chosen transverse shapes. We present a general method to construct such beams in the paraxial and nonparaxial regime and demonstrate experimentally their propagation in the paraxial case. The key ingredient of our method is the use of the spectral representation of the accelerating beams, which offers a unique and compact description of these beams. The on-demand accelerating light patterns described here are likely to give rise to new applications and add versatility to the current ones.
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Reversal of ? cell de-differentiation by a small molecule inhibitor of the TGF? pathway.
Elife
PUBLISHED: 03-16-2014
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Dysfunction or death of pancreatic ? cells underlies both types of diabetes. This functional decline begins with ? cell stress and de-differentiation. Current drugs for type 2 diabetes (T2D) lower blood glucose levels but they do not directly alleviate ? cell stress nor prevent, let alone reverse, ? cell de-differentiation. We show here that Urocortin 3 (Ucn3), a marker for mature ? cells, is down-regulated in the early stages of T2D in mice and when ? cells are stressed in vitro. Using an insulin expression-coupled lineage tracer, with Ucn3 as a reporter for the mature ? cell state, we screen for factors that reverse ? cell de-differentiation. We find that a small molecule inhibitor of TGF? receptor I (Alk5) protects cells from the loss of key ? cell transcription factors and restores a mature ? cell identity even after exposure to prolonged and severe diabetes.
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Detection of solar wind-produced water in irradiated rims on silicate minerals.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 01-21-2014
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The solar wind (SW), composed of predominantly ?1-keV H(+) ions, produces amorphous rims up to ?150 nm thick on the surfaces of minerals exposed in space. Silicates with amorphous rims are observed on interplanetary dust particles and on lunar and asteroid soil regolith grains. Implanted H(+) may react with oxygen in the minerals to form trace amounts of hydroxyl (-OH) and/or water (H2O). Previous studies have detected hydroxyl in lunar soils, but its chemical state, physical location in the soils, and source(s) are debated. If -OH or H2O is generated in rims on silicate grains, there are important implications for the origins of water in the solar system and other astrophysical environments. By exploiting the high spatial resolution of transmission electron microscopy and valence electron energy-loss spectroscopy, we detect water sealed in vesicles within amorphous rims produced by SW irradiation of silicate mineral grains on the exterior surfaces of interplanetary dust particles. Our findings establish that water is a byproduct of SW space weathering. We conclude, on the basis of the pervasiveness of the SW and silicate materials, that the production of radiolytic SW water on airless bodies is a ubiquitous process throughout the solar system.
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IV Acetaminophen: Efficacy of a Single Dose for Postoperative Pain After Hip Arthroplasty: Subset Data Analysis of 2 Unpublished Randomized Clinical Trials.
Am J Ther
PUBLISHED: 01-14-2014
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Inadequate control of postoperative pain after orthopedic procedures may trigger complications that increase morbidity. Multimodal analgesia is used to manage pain effectively after surgical procedures and reduce the need for rescue analgesia. Intravenous (IV) acetaminophen (OFIRMEV; Cadence Pharmaceuticals, Inc.), an analgesic that has been studied and used in the multimodal management of acute pain after major orthopedic procedures, combines the safety seen with oral and rectal formulations with a preferred route of administration. Two double-blind, randomized, placebo-controlled clinical trials were conducted (total 130 patients) to determine the efficacy and safety of single-dose IV acetaminophen in patients following total hip arthroplasty. Although both studies were stopped prematurely, overlap in patient populations, study design, and methodologies in the single-dose phase of these studies allowed for analysis of their results to be presented concurrently. Both trials demonstrated IV acetaminophen having greater efficacy than placebo in terms of primary endpoints [pain intensity differences from T0.5 to T3 (P < 0.05 in both studies)]. The use of IV acetaminophen also reduced the need for rescue opioid consumption, with patients receiving IV acetaminophen consuming, on average, less than half the amount of rescue medication as those receiving placebo. IV acetaminophen was effective in treating moderate-to-severe pain after total hip arthroplasty and reduced the need for rescue opioid consumption.
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CXC chemokine receptor 4 signaling upon co-activation with stromal cell-derived factor-1? and ubiquitin.
Cytokine
PUBLISHED: 08-22-2013
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Recently, we reported that extracellular ubiquitin functions as another agonist of CXC chemokine receptor (CXCR)4. Whereas the cognate CXCR4 ligand, stromal cell-derived factor (SDF)-1?, is also a CXCR7 agonist, ubiquitin does not bind to CXCR7. Because both ligands are present in the extracellular environment, co-activation of CXCR4 appears to be physiologically relevant. CXCR4 mediated effects of ubiquitin, however, are not well understood and consequences of co-activation of CXCR4 with both ligands are unknown. Utilizing proximity ligation assays and flow cytometry, we detected CXCR4, but not CXCR7, on the cell surface of THP-1 cells, which suggests that confounding effects of CXCR7 are unlikely. Time course and magnitude of reduction of cell surface CXCR4 expression were comparable after stimulation of THP-1 cells with both ligands. SDF-1? was more efficacious than ubiquitin to mobilize Ca(2+). Co-stimulation of THP-1 cells with both ligands resulted in synergistic effects on Ca(2+) fluxes at suboptimal ligand concentrations. Homologous desensitization of Ca(2+) fluxes was detectable with both ligands. SDF-1? pre-stimulation desensitized ubiquitin induced Ca(2+) fluxes, but not vice versa. Effects of SDF-1? and ubiquitin on cAMP levels, Akt and ERK1/2 phosphorylation and chemotactic responses were additive. The chemotactic activities of ubiquitin and SDF-1? were sensitive to AMD3100, pertussis toxin, U73122, LY94002 and U0126. These data suggest that CXCR4 activation with SDF-1? and ubiquitin results in partially synergistic effects on cellular signaling events and in differential effects on receptor desensitization. The ligand ratio that is present in the extracellular environment may contribute to the regulation of CXCR4 mediated functions.
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Generalized diffractive optical elements with asymmetric harmonic response and phase control.
Appl Opt
PUBLISHED: 06-06-2013
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We report a method to generate phase-only diffractive beam splitters allowing asymmetry of the target diffracted orders, as well as providing a tailored phase difference between the diffracted orders. We apply a well-established design method that requires the determination of a set of numerical parameters, and avoids the use of image iterative algorithms. As a result, a phase lookup table is determined that can be used for any situation where a first-order (blazed) diffractive element is modified to produce higher orders with desired intensity and/or phase relation. As examples, we demonstrate the phase difference control on triplicators, as well as on other generalized diffractive elements like bifocal Fresnel lenses and phase masks for the generation of vortex beams. Results are experimentally demonstrated by encoding the calculated phase pattern onto parallel-aligned liquid crystal spatial light modulators.
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Using a bayesian latent class model to evaluate the utility of investigating persons with negative polymerase chain reaction results for pertussis.
Am. J. Epidemiol.
PUBLISHED: 06-04-2013
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Pertussis remains difficult to control. Imperfect sensitivity of diagnostic tests and lack of specific guidance regarding interpretation of negative test results among patients with compatible symptoms may contribute to its spread. In this study, we examined whether additional pertussis cases could be identified if persons with negative pertussis test results were routinely investigated. We conducted interviews among 250 subjects aged ?18 years with pertussis polymerase chain reaction (PCR) results reported from 2 reference laboratories in Wisconsin during July-September 2010 to determine whether their illnesses met the Centers for Disease Control and Preventions clinical case definition (CCD) for pertussis. PCR validity measures were calculated using the CCD as the standard for pertussis disease. Two Bayesian latent class models were used to adjust the validity measures for pertussis detectable by 1) culture alone and 2) culture and/or more sensitive measures such as serology. Among 190 PCR-negative subjects, 54 (28%) had illnesses meeting the CCD. In adjusted analyses, PCR sensitivity and the negative predictive value were 1) 94% and 99% and 2) 43% and 87% in the 2 types of models, respectively. The models suggested that public health follow-up of reported pertussis patients with PCR-negative results leads to the detection of more true pertussis cases than follow-up of PCR-positive persons alone. The results also suggest a need for a more specific pertussis CCD.
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A large community outbreak of blastomycosis in wisconsin with geographic and ethnic clustering.
Clin. Infect. Dis.
PUBLISHED: 06-03-2013
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Blastomycosis is a potentially life-threatening infection caused by the soil-based dimorphic fungus Blastomyces dermatitidis, which is endemic throughout much of the Midwestern United States. We investigated an increase in reported cases of blastomycosis that occurred during 2009-2010 in Marathon County, Wisconsin.
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Induction of spermatogenic synchrony by retinoic acid in neonatal mice.
Spermatogenesis
PUBLISHED: 05-21-2013
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Retinoic acid (RA) is required for the successful differentiation and meiotic entry of germ cells in the murine testis. The availability of RA to undifferentiated germ cells begins in a variable, uneven pattern during the first few days after birth and establishes the asynchronous pattern of germ cell differentiation in adulthood. It has been shown that synchronous spermatogenesis can be induced in 2 d postpartum mice, but not in adult mice, by treating vitamin A sufficient males with RA. In this study, neonatal males were treated at different ages with a single dose of RA and spermatogenesis was examined after recovery to adulthood. The failure of exogenous RA to alter asynchrony correlates with the appearance of meiotic preleptotene spermatocytes within the seminiferous epithelium.
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Direct generation of abruptly focusing vortex beams using a 3/2 radial phase-only pattern.
Appl Opt
PUBLISHED: 03-23-2013
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Abruptly focusing Airy beams have previously been generated using a radial cubic phase pattern that represents the Fourier transform of the Airy beam. The Fourier transform of this pattern is formed using a system length of 2f, where f is the focal length of the Fourier transform lens. In this work, we directly generate these abruptly focusing Airy beams using a 3/2 radial phase pattern encoded onto a liquid crystal display. The resulting optical system is much shorter. In addition, we can easily produce vortex patterns at the focal point of these beams. Experimental results match theoretical predictions.
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Outcomes of allogeneic hematopoietic cell transplantation in patients with dyskeratosis congenita.
Biol. Blood Marrow Transplant.
PUBLISHED: 02-28-2013
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We describe outcomes after allogeneic transplantation in 34 patients with dyskeratosis congenita who underwent transplantation between 1981 and 2009. The median age at transplantation was 13 years (range, 2 to 35). Approximately 50% of transplantations were from related donors. Bone marrow was the predominant source of stem cells (24 of 34). The day-28 probability of neutrophil recovery was 73% and the day-100 platelet recovery was 72%. The day-100 probability of grade II to IV acute GVHD and the 3-year probability of chronic graft-versus-host disease were 24% and 37%, respectively. The 10-year probability of survival was 30%; 14 patients were alive at last follow-up. Ten deaths occurred within 4 months from transplantation because of graft failure (n = 6) or other transplantation-related complications; 9 of these patients had undergone transplantation from mismatched related or from unrelated donors. Another 10 deaths occurred after 4 months; 6 of them occurred more than 5 years after transplantation, and 4 of these were attributed to pulmonary failure. Transplantation regimen intensity and transplantations from mismatched related or unrelated donors were associated with early mortality. Transplantation of grafts from HLA-matched siblings with cyclophosphamide-containing nonradiation regimens was associated with early low toxicity. Late mortality was attributed mainly to pulmonary complications and likely related to the underlying disease.
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An outbreak of foodborne illness among attendees of a wedding reception in Wisconsin likely caused by Arcobacter butzleri.
Foodborne Pathog. Dis.
PUBLISHED: 02-04-2013
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Arcobacter species, primarily Arcobacter butzleri, are widely distributed among animals, infrequently isolated from humans, and previously not associated with outbreaks of foodborne illness. We report results of an investigation of a foodborne outbreak that occurred among attendees of a wedding reception in Wisconsin, United States, and was likely caused by A. butzleri.
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Characterization of polymeric microcapsules containing a low molecular weight peptide for controlled release.
Microsc. Microanal.
PUBLISHED: 01-29-2013
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A need exists to prolong the release of rapidly metabolized peptides of a low molecular weight, while delivering this peptide without environmental interference. Previous studies have used bovine serum albumin (BSA) as a model peptide to study release characteristics from alginate microcapsules. BSA is 66 kDa in size, while the peptide of interest here, connexin-43 carboxyl-terminus mimetic peptide (?CT1), is only 3.4 kDa. Such a change in size results in a much different set of release parameters. Our overall goal is a sustained release over a 24+ h period. Prolonged application of the peptide to a wound site to investigate therapeutic effects is ideal. As a result, a diffusion method using alginate microcapsules, along with the addition of poly-l-lysine and poly-l-ornithine, has been explored. We first aimed to establish and characterize our parameters through a set of parametric tests. Variations in polymer coating, change in pH, and changes in loading ratio have previously been shown to effect release using model compounds. Here we test specific changes in these parameters to show effects on the release of ?CT1. Additionally, the microcapsules were attached to several biomaterials and surgical implants by ultraviolet cross-linking to study the effectiveness of attachment and delivery. Analysis and measurements using phase contrast microscopy, scanning electron microscopy, and atomic force microscopy were used to characterize changes in microcapsule morphology.
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Desorption electrospray ionization imaging mass spectrometry as a tool for investigating model prebiotic reactions on mineral surfaces.
Anal. Chem.
PUBLISHED: 01-10-2013
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Mineral-assisted thermal decomposition of formamide (HCONH(2)) is a heavily studied model prebiotic reaction that has offered valuable insights into the plausible pathways leading to the chemical building blocks of primordial informational polymers. To date, most efforts have focused on the analysis of formamide reaction products released in solution, although several studies have examined the role of mineral catalysts in promoting this chemistry. We show here that the direct investigation of reactive mineral surfaces by desorption electrospray ionization-mass spectrometry imaging (DESI-MSI) gives a new perspective on the important role of the mineral surface in the formation of reaction products. As a proof-of-principle example, we show that DESI-MSI allows interrogation of the molecular products produced on heterogeneous granite samples with minimal sample preparation. Purine and pyrimidine nucleobases and their derivatives are successfully detected by DESI-MSI, with a strong correlation of the spatial product distribution with the mineral microenvironment. To our knowledge, this study is the first application of DESI-MSI to the study of complex and porous mineral surfaces and their roles in chemical evolution. This DESI-MSI approach is generally applicable to a wide range of reactions or other processes involving minerals.
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Reflections on a career in optics at San Diego State University [Invited].
Appl Opt
PUBLISHED: 01-08-2013
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As part of the 50 year celebration of Applied Optics, the Optical Society has recognized the 50 most prolific authors for that journal during this period and asked them for reflections and comments on their careers and the field of optics. This is my contribution.
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An outbreak of Legionnaires disease associated with a decorative water wall fountain in a hospital.
Infect Control Hosp Epidemiol
PUBLISHED: 12-23-2011
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To detect an outbreak-related source of Legionella, control the outbreak, and prevent additional Legionella infections from occurring.
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Flood volcanism in the northern high latitudes of Mercury revealed by MESSENGER.
Science
PUBLISHED: 10-01-2011
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MESSENGER observations from Mercury orbit reveal that a large contiguous expanse of smooth plains covers much of Mercurys high northern latitudes and occupies more than 6% of the planets surface area. These plains are smooth, embay other landforms, are distinct in color, show several flow features, and partially or completely bury impact craters, the sizes of which indicate plains thicknesses of more than 1 kilometer and multiple phases of emplacement. These characteristics, as well as associated features, interpreted to have formed by thermal erosion, indicate emplacement in a flood-basalt style, consistent with x-ray spectrometric data indicating surface compositions intermediate between those of basalts and komatiites. The plains formed after the Caloris impact basin, confirming that volcanism was a globally extensive process in Mercurys post-heavy bombardment era.
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Effects of the optical system on the output from wavefront coding masks.
Opt Express
PUBLISHED: 09-22-2011
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We show that the output from wavefront coding systems depends critically upon the optical imaging system. Our analysis is based on results using nondiffracting accelerated Airy beams. We review the similarities and critical differences between various optical systems and show computational results. We suggest new directions for improving the performance of these wavefront coding masks.
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An examination of kernite (Na2B4O6(OH)2·3H2O) using X-ray and electron spectroscopies: quantitative microanalysis of a hydrated low-Z mineral.
Microsc. Microanal.
PUBLISHED: 09-06-2011
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Mineral borates, the primary industrial source of boron, are found in a large variety of compositions. One such source, kernite (Na2B4O6(OH)2·3H2O), offers an array of challenges for traditional electron-probe microanalysis (EPMA)-it is hygroscopic, an electrical insulator, composed entirely of light elements, and sensitive to both low pressures and the electron beam. However, the approximate stoichiometric composition of kernite can be analyzed with careful preparation, proper selection of reference materials, and attention to the details of quantification procedures, including correction for the time dependency of the sodium X-ray signal. Moreover, a reasonable estimation of the minerals water content can also be made by comparing the measured oxygen to the calculated stoichiometric oxygen content. X-ray diffraction, variable-pressure electron imaging, and visual inspection elucidate the structural consequences of high vacuum treatment of kernite, while Auger electron spectroscopy and X-ray photoelectron spectroscopy confirm electron beam-driven migration of sodium and oxygen out of the near-surface region (sampling depth ? 2 nm). These surface effects are insufficiently large to significantly affect the EPMA results (sampling depth ? 400 nm at 5 keV).
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Evaluation of the genotoxicity of the food additive, gum ghatti.
Food Chem. Toxicol.
PUBLISHED: 08-24-2011
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Gum ghatti is a food additive in some parts of the world, serving as an emulsifier, a stabilizer, and a thickening agent. To evaluate its genotoxic potential, we conducted Good Laboratory Practice compliant in vitro and in vivo studies in accordance with the Organisation for Economic Co-operation and Development (OECD) guidelines. No evidence of toxicity or mutagenicity was detected in a bacterial reverse mutation assay using five tester strains evaluating gum ghatti at up to 6 mg/plate, with or without metabolic activation. Gum ghatti also did not induce chromosome structural damage in a chromosome aberration assay using Chinese hamster ovary cells. To assess the ability to induce DNA damage in rodents, a combined micronucleus/Comet assay was conducted in male B6C3F1 mice. Gum ghatti was administered at 1000, 1500, and 2000 mg/kg/day by gavage once daily for 4 days and samples were collected 4h after the final dosing. No effect of gum ghatti was measured on micronucleated reticulocyte (MN-RET) frequency in peripheral blood, or DNA damage in blood leukocytes or liver as assessed by the Comet assay. Our results show no evidence of genotoxic potential of gum ghatti administered up to the maximum concentrations recommended by OECD guidelines.
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Emergence of a new pathogenic Ehrlichia species, Wisconsin and Minnesota, 2009.
N. Engl. J. Med.
PUBLISHED: 08-05-2011
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Ehrlichiosis is a clinically important, emerging zoonosis. Only Ehrlichia chaffeensis and E. ewingii have been thought to cause ehrlichiosis in humans in the United States. Patients with suspected ehrlichiosis routinely undergo testing to ensure proper diagnosis and to ascertain the cause.
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Fraunhofer diffraction of a partially blocked spiral phase plate.
Opt Express
PUBLISHED: 07-13-2011
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The Fraunhofer diffraction pattern from a partially blocked spiral phase plate (SPP) produces a partial vortex output pattern that is rotated by 90 degrees compared with the input. The rotation direction depends on whether the angular phase pattern increases in the clockwise or counterclockwise direction. In this work, we present an explanation of this effect based on careful examination of classical diffraction theory and show new experimental results. This approach is very convenient for easily determining the sign of the vortex charge.
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Creating three-dimensional lattice patterns using programmable Dammann gratings.
Appl Opt
PUBLISHED: 07-12-2011
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We demonstrate the creation of a three dimensional (3D) lattice of focus spots using a 3D Dammann grating structure. Such a 3D lattice of focus spots can be used for probing 3D structures or for creating 3D photonic crystal structures in optically sensitive media. Experimental results are included where the patterns are encoded onto a programmable liquid crystal display. We demonstrate the generation of five planar arrays each having 6×6 points surrounding another set of four planar arrays each having 5×5 points with a single pattern.
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Interlaboratory study comparison of the 15-day intact adult male rat screening assay: evaluation of an antithyroid chemical and a negative control chemical.
Birth Defects Res. B Dev. Reprod. Toxicol.
PUBLISHED: 06-21-2011
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Validation of the 15-day intact adult male rat screening assay (IAMRSA), an endocrine activity screen, was extended beyond the 28 substances evaluated to date. Two independent laboratories evaluated specificity using allyl alcohol (AA), a putative negative control, and DE-71 (technical grade pentabromodiphenyl ether) for comparison with previous pubertal assays that demonstrated thyroid effects. Male rats (15/group) were gavaged daily with AA (0, 10, 30, or 40 mg/kg/day) or DE-71 (0, 3, 30, or 60 mg/kg/day) for 15 days. Body and organ weights and serum hormone concentrations were measured, and a limited histopathological assessment was conducted. AA results were considered negative at doses that did not exceed the maximum tolerated dose (MTD); effects reported were dose-related decreases in weight gain, increased liver weights and, although the pattern varied across studies, alterations in some androgen-sensitive endpoints in the high-dose where the maximum tolerated dose was exceeded. In the DE-71 studies, dose-dependent increases in liver weights (consistent with hepatic enzyme induction), decreases in tri-iodothyronine and thyroxine, concomitant thyroid stimulating hormone increases were observed and one laboratory reported histopathological thyroid changes in mid- and high-dose groups, and the other increased thyroid weights. For DE-71, the IAMRSA was comparable in sensitivity to the pubertal assays. Overall, the specificity and sensitivity of the IAMRSA for deployment in an endocrine screening battery are supported. However, differentiating primary endocrine-mediated effects from secondary effects caused by systemic toxicity will be challenging, emphasizing the need to utilize a battery of assays and a weight of evidence approach when evaluating the potential endocrine activity of chemicals.
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Bridging the micro-to-macro gap: a new application for micro X-ray fluorescence.
Microsc. Microanal.
PUBLISHED: 05-24-2011
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X-ray elemental mapping and X-ray spectrum imaging are powerful microanalytical tools. However, their scope is often limited spatially by the raster area of a scanning electron microscope or microprobe. Limited sampling size becomes a significant issue when large area (>10 cm²), heterogeneous materials such as concrete samples or others must be examined. In such specimens, macro-scale structures, inclusions, and concentration gradients are often of interest, yet microbeam methods are insufficient or at least inefficient for analyzing them. Such requirements largely exclude the samples of interest presented in this article from electron probe microanalysis. Micro X-ray fluorescence-X-ray spectrum imaging (?XRF-XSI) provides a solution to the problem of macro-scale X-ray imaging through an X-ray excitation source, which can be used to analyze a variety of large specimens without many of the limitations found in electron-excitation sources. Using a mid-sized beam coupled with an X-ray excitation source has a number of advantages, such as the ability to work at atmospheric pressure and lower limits of detection owing to the absence of electron-induced bremsstrahlung. ?XRF-XSI also acts as a complement, where applicable, to electron microbeam X-ray output, highlighting areas of interest for follow-up microanalysis at a finer length scale.
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Solving structure in the CP29 light harvesting complex with polarization-phased 2D electronic spectroscopy.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 02-14-2011
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The CP29 light harvesting complex from green plants is a pigment-protein complex believed to collect, conduct, and quench electronic excitation energy in photosynthesis. We have spectroscopically determined the relative angle between electronic transition dipole moments of its chlorophyll excitation energy transfer pairs in their local protein environments without relying on simulations or an X-ray crystal structure. To do so, we measure a basis set of polarized 2D electronic spectra and isolate their absorptive components on account of the tensor relation between the light polarization sequences used to obtain them. This broadly applicable advance further enhances the acuity of polarized 2D electronic spectroscopy and provides a general means to initiate or feed back on the structural modeling of electronically-coupled chromophores in condensed phase systems, tightening the inferred relations between the spatial and electronic landscapes of ultrafast energy flow. We also discuss the pigment composition of CP29 in the context of light harvesting, energy channeling, and photoprotection within photosystem II.
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Comparison of patients hospitalized with pandemic 2009 influenza A (H1N1) virus infection during the first two pandemic waves in Wisconsin.
J. Infect. Dis.
PUBLISHED: 01-28-2011
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Wisconsin was severely affected by pandemic waves of 2009 influenza A H1N1 infection during the period 15 April through 30 August 2009 (wave 1) and 31 August 2009 through 2 January 2010 (wave 2).
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Exposure to retinoic acid in the neonatal but not adult mouse results in synchronous spermatogenesis.
Biol. Reprod.
PUBLISHED: 01-12-2011
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Retinoic acid (RA) is required for germ cell differentiation, the regulation of which gives rise to a constant production of mature sperm. In testes from 3-day postpartum (dpp) RARE-hsplacZ mice, periodic regions positive for beta-galactosidase activity were observed along the length of the seminiferous tubules. Periodicity was abolished by treatment of neonates with exogenous RA at 2 dpp. To assess the consequences, 2-dpp mice were treated with RA, and the long- and short-term effects were assessed. Long-term effects of neonatal RA exposure included a delay in the appearance of advanced germ cells and the absence of a spermatogenic wave (synchronous spermatogenesis) in the adult. In contrast, RA exposure in vitamin A-sufficient adults did not result in synchronous spermatogenesis but rather induced apoptosis in a subset of spermatogonia. Shortly after (24 h) neonates were exposed, altered expression of known germ cell differentiation and the (Stra8, Kit, Sycp3, and Rec8) meiosis markers and an increase in the number of STRA8 and SYCP3 immunopositive cells were observed relative to those of vehicle controls. However, 48 and 72 h after exposure, a significant reduction in the number of STRA8 and SYCP3 immunopositive cells occurred. Immunohistochemical analysis of a marker for apoptosis demonstrated neonatal exposure resulted in increased germ cell apoptosis, as observed in the adult. Additionally, RA exposure resulted in increased Cyp26a1 expression of the RA-degrading enzyme. Thus, while RA treatment of neonatal and adult mice resulted in apoptosis of spermatogonia, synchronous spermatogenesis occurred only after neonatal RA exposure.
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The mechanical coupling of adult marrow stromal stem cells during cardiac regeneration assessed in a 2-D co-culture model.
Biomaterials
PUBLISHED: 01-05-2011
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Postnatal cardiomyocytes undergo terminal differentiation and a restricted number of human cardiomyocytes retain the ability to divide and regenerate in response to ischemic injury. However, whether these neo-cardiomyocytes are derived from endogenous population of resident cardiac stem cells or from the exogenous double assurance population of resident bone marrow-derived stem cells that populate the damaged myocardium is unresolved and under intense investigation. The vital challenge is to ameliorate and/or regenerate the damaged myocardium. This can be achieved by stimulating proliferation of native quiescent cardiomyocytes and/or cardiac stem cell, or by recruiting exogenous autologous or allogeneic cells such as fetal or embryonic cardiomyocyte progenitors or bone marrow-derived stromal stem cells. The prerequisites are that these neo-cardiomyocytes must have the ability to integrate well within the native myocardium and must exhibit functional synchronization. Adult bone marrow stromal cells (BMSCs) have been shown to differentiate into cardiomyocyte-like cells both in vitro and in vivo. As a result, BMSCs may potentially play an essential role in cardiac repair and regeneration, but this concept requires further validation. In this report, we have provided compelling evidence that functioning cardiac tissue can be generated by the interaction of multipotent BMSCs with embryonic cardiac myocytes (ECMs) in two-dimensional (2-D) co-cultures. The differentiating BMSCs were induced to undergo cardiomyogenic differentiation pathway and were able to express unequivocal electromechanical coupling and functional synchronization with ECMs. Our 2-D co-culture system provides a useful in vitro model to elucidate various molecular mechanisms underpinning the integration and orderly maturation and differentiation of BMSCs into neo-cardiomyocytes during myocardial repair and regeneration.
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Clinical risk management approach for long-duration space missions.
Aviat Space Environ Med
PUBLISHED: 12-27-2010
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In the process of crewmember evaluation and certification for long-duration orbital missions, the International Space Station (ISS) Multilateral Space Medicine Board (MSMB) encounters a surprisingly wide spectrum of clinical problems. Some of these conditions are identified within the ISS Medical Standards as requiring special consideration, or as falling outside the consensus Medical Standards promulgated for the ISS program.
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Analysis of multilevel spiral phase plates using a Dammann vortex sensing grating.
Opt Express
PUBLISHED: 12-18-2010
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Optical vortices can be easily generated using a multilevel spiral phase plate (SPP). However the quality of the generated vortex beam depends on the number of phase segments. We review the theory for this multilevel SPP using a Fourier expansion of integer topological charged vortices. We then experimentally examine the validity of this expansion using a fabricated Dammann vortex diffraction grating spectrum analyzer. The Dammann vortex diffraction grating is fabricated using SU-8 photoresist on glass substrate and yields uniform diffraction efficiency across a desired number of diffracted orders. Experimental results show the extra angular harmonics of a multilevel SPP and agree with the theory.
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Elevated AKR1C3 expression promotes prostate cancer cell survival and prostate cell-mediated endothelial cell tube formation: implications for prostate cancer progression.
BMC Cancer
PUBLISHED: 12-06-2010
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Aldo-keto reductase (AKR) 1C family member 3 (AKR1C3), one of four identified human AKR1C enzymes, catalyzes steroid, prostaglandin, and xenobiotic metabolism. In the prostate, AKR1C3 is up-regulated in localized and advanced prostate adenocarcinoma, and is associated with prostate cancer (PCa) aggressiveness. Here we propose a novel pathological function of AKR1C3 in tumor angiogenesis and its potential role in promoting PCa progression.
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Seoul virus infection in a Wisconsin patient with recent travel to China, March 2009: first documented case in the Midwestern United States.
Am. J. Trop. Med. Hyg.
PUBLISHED: 12-02-2010
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Diagnosis of Seoul virus-associated hemorrhagic fever with renal syndrome (HFRS) cases among United States residents is rare. We describe confirmation of a Seoul virus infection in a 36-year-old scientist who worked with laboratory rats in Milwaukee, Wisconsin, but most likely acquired the infection during a trip to Shenyang, China.
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Matrix isolation ESR and theoretical studies of metal phosphides.
J Chem Phys
PUBLISHED: 11-02-2010
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The ZnP, (67)ZnP, CdP, (111)CdP, and (113)CdP radicals have been formed by laser ablation of the metal with GaP pressed into the metal surface, isolated in an inert neon matrix at 4.3 K and their electronic structure was established using electron spin resonance spectroscopy. The following magnetic parameters were determined experimentally for ZnP/(67)ZnP, g(?)=1.9982(2), A(?)(P)=111(6)?MHz, A(?)((67)Zn)=160(2)?MHz, and D=-29?988(3)?MHz and estimates were made for the following ZnP/(67)ZnP magnetic parameters: g(?)=1.9941(2), A(?)(P)=-5(6)?MHz, and A(?)((67)Zn)=180(50)?MHz. The following magnetic parameters for CdP/(111)CdP/(113)CdP were determined experimentally: g(?)=1.9963(2), A(?)(P)=97(3)?MHz, A(?)((111)Cd)=862(3)?MHz, and A(?)((113)Cd)=902(3)?MHz. Evidence for the formation of the MgP radical was also obtained and an approximate hyperfine coupling constant of A(?)(P)=157(6)?MHz was determined. The low-lying electronic states of ZnP and MgP were also investigated using the multiconfigurational self-consistent field technique. Potential energy surfaces, binding energies, optimized bond lengths, energy separations, and dissociation energies have been determined. Both radicals are found to have (4)?(-) ground states with a leading configuration at r(e) of 10?(2)11?(2)5?(1)5?(1)12?(1) for ZnP and 7?(2)8?(2)3?(1)3?(1)9?(1) for MgP. Significant mixing to this state is calculated for MgP.
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Non-rural point source blastomycosis outbreak near a yard waste collection site.
Clin Med Res
PUBLISHED: 10-25-2010
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Blastomycosis is a potentially fatal infection caused by the fungus Blastomyces dermatitidis. During January 1 through March 5, 2006, twenty-one laboratory confirmed cases of blastomycosis were reported among residents of an endemic area in north-central Wisconsin; a striking increase compared with previous years. The objective of the study was to determine if an observed increase in blastomycosis among residents of an urban area in north-central Wisconsin was caused by a point-source exposure and to identify its source.
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Extended phase modulation depth in twisted nematic liquid crystal displays.
Appl Opt
PUBLISHED: 10-22-2010
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We show how the phase modulation depth in twisted nematic liquid crystal displays (TNLCDs) can be increased dramatically by selecting a polarization configuration with a reduced mean intensity transmission. This phenomenon, which we have validated with various devices, is shown here for a device that presents a phase-only modulation only slightly over ? radians in our classical rotated eigenvector configuration, but it is capable of producing close to a 2? phase depth for a configuration with 5% mean intensity transmission. A quantitative explanation is presented by means of a phasor analysis of the TNLCD eigenvector projections over input and output polarization states. The proposed technique can be a very useful solution in modern TNLCDs that have a very thin liquid crystal layer and a reduced maximum achievable phase modulation.
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Epidemiologic and clinical features among patients hospitalized in Wisconsin with 2009 H1N1 influenza A virus infections, April to August 2009.
WMJ
PUBLISHED: 10-16-2010
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During April 15 through July 23, 2009, Wisconsin reported the most confirmed and probable cases of 2009 influenza A (H1N1) virus (2009 H1N1) infection in the United States. Preliminary reports suggest that 2009 H1N1 infection disproportionately affected minority populations.
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Stability of a volatile liquid film spreading along a heterogeneously-heated substrate.
J Colloid Interface Sci
PUBLISHED: 09-17-2010
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The dynamics and stability of a thin, viscous film of volatile liquid flowing under the influence of gravity over a non-uniformly heated substrate are investigated using lubrication theory. Attention is focused on the regime in which evaporation balances the flow due to gravity. The film terminates above the heater at an apparent contact line, with a microscopically thin precursor film adsorbed due to the disjoining pressure. The film develops a weak thermocapillary ridge due to the Marangoni stress at the upstream edge of the heated region. As for spreading films, a more significant ridge is formed near the apparent contact line. For weak Marangoni effects, the film evolves to a steady profile. For stronger Marangoni effects, the film evolves to a time-periodic state. Results of a linear stability analysis reveal that the steady film is unstable to transverse perturbations above a critical value of the Marangoni parameter, leading to finger formation at the contact line. The streamwise extent of the fingers is limited by evaporation. The time-periodic profiles are always unstable, leading to the formation of periodically-oscillating fingers. For rectangular heaters, the film profiles after instability onset are consistent with images from published experimental studies.
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DLVO interaction of colloidal particles with topographically and chemically heterogeneous surfaces.
J Colloid Interface Sci
PUBLISHED: 06-21-2010
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The DLVO force and potential energy of interaction between microspheres and topographically and chemically heterogeneous surfaces in aqueous solution are computed using a modification of the surface element integration approach. The heterogeneous surface has an array of cylindrical pillars of varying height, diameter, and arrangement to model different nano-topographies. In agreement with previous studies, the nano-topography decreases the size of the potential energy barrier for unfavorable surfaces because the pillars limit the minimum separation distance. The influence of topography is significant even for pillars several nanometers high and is more pronounced if the surface potential of the pillar tops differs from that of the underlying surface. A new force- and energy-averaging model is introduced as a simple method to compute the mean interaction energy or force between the particle and a heterogeneous surface, which differs significantly from a mean-field approach based on the average or nominal surface potential. Small variations in topography are found to remove large energy barriers to colloidal deposition. These results help explain the increased attraction of patchy surfaces towards particles relative to expectations based on typical DLVO calculations, which is particularly significant for surfaces with adsorbed polyelectrolytes.
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Encoding generalized phase functions on Dammann gratings.
Opt Lett
PUBLISHED: 05-19-2010
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We extend the Dammann encoding concept to more general phase functions, i.e., to encode a phase pattern so that a number of diffracted orders have the same intensity. We demonstrate a Dammann vortex grating that generates different vortex patterns in the different diffracted orders. We also show a Fresnel lens that creates seven transverse focal spots in each of seven axial planes.
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Tickborne Powassan virus infections among Wisconsin residents.
WMJ
PUBLISHED: 05-07-2010
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Powassan virus (POWV) is a tickborne Flavivirus that causes a rare but potentially life-threatening illness. The first reported case of POWV infection in a Wisconsin resident occurred in 2003. Enhanced surveillance and testing detected 2 additional cases.
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Decomposition of radially and azimuthally polarized beams using a circular-polarization and vortex-sensing diffraction grating.
Opt Express
PUBLISHED: 04-15-2010
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Both radially polarized and azimuthally polarized beams can be decomposed into linear combinations of circularly polarized vortex beams having opposite vortex charges. We show experimental evidence for this decomposition using a specially designed vortex sensing diffraction grating that generates multiple vortex patterns having different senses of circularly polarization in the different diffracted orders. When this grating is illuminated with a radially or azimuthally polarized beam, the grating separates the components into different diffracted orders. Experimental results are shown.
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A 3-D cardiac muscle construct for exploring adult marrow stem cell based myocardial regeneration.
Biomaterials
PUBLISHED: 01-09-2010
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Adult bone marrow stromal cells (BMSCs) are capable of differentiating into cardiomyocyte-like cells in vitro and contribute to myocardial regeneration in vivo. Consequently, BMSCs may potentially play a vital role in cardiac repair and regeneration. However, this concept has been limited by inadequate and inconsistent differentiation of BMSCs into cardiomyocytes along with poor survival and integration of neo-cardiomyocytes after implantation into ischemic myocardium. In order to overcome these barriers and to explore adult stem cell based myocardial regeneration, we have developed an in vitro model of three-dimensional (3-D) cardiac muscle using rat ventricular embryonic cardiomyocytes (ECMs) and BMSCs. When ECMs and BMSCs were seeded sequentially onto a 3-D tubular scaffold engineered from topographically aligned type I collagen-fibers and cultured in basal medium for 7, 14, 21, or 28 days, the maturation and co-differentiation into a cardiomyocyte lineage was observed. Phenotypic induction was characterized at morphological, immunological, biochemical and molecular levels. The observed expression of transcripts coding for cardiomyocyte phenotypic markers and the immunolocalization of cardiomyogenic lineage-associated proteins revealed typical expression patterns of neo-cardiomyogenesis. At the biochemical level differentiating cells exhibited appropriate metabolic activity and at the ultrastructural level myofibrillar and sarcomeric organization were indicative of an immature phenotype. Our 3-D co-culture system sustains the ECMs in vitro continuum of differentiation process and simultaneously induces the maturation and differentiation of BMSCs into cardiomyocyte-like cells. Thus, this novel 3-D co-culture system provides a useful in vitro model to investigate the functional role and interplay of developing ECMs and BMSCs during cardiomyogenic differentiation.
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Infant deaths associated with human parechovirus infection in Wisconsin.
Clin. Infect. Dis.
PUBLISHED: 01-06-2010
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From December 1987 through August 2004, lung tissue, nasopharyngeal swabs, and colon swab specimens obtained during 1263 autopsies of infants and young children were examined to assess the role of viruses in deaths of children aged <2 years.
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Travel-associated Dengue illnesses among Wisconsin residents, 2002-2008.
WMJ
PUBLISHED: 12-04-2009
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Dengue infections in humans can result in self-limited illness or conditions that can be severe and life-threatening. Persons traveling to many tropical regions are at risk for dengue infection. This report retrospectively summarizes travel-associated dengue cases occurring among Wisconsin residents from 2002 through 2008.
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Vortex sensing diffraction gratings.
Opt Lett
PUBLISHED: 10-02-2009
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We demonstrate a specially designed vortex sensing diffraction grating that generates multiple vortex patterns in the different diffracted orders. When this grating is illuminated with a separate vortex beam, the sign and order of the topological charge of the incident beam can be easily detected. Experimental results are shown for a variety of vortex beams including fractional values of the topological charge, and where both the diffraction grating and incident vortex illumination beam are generated by two different liquid crystal displays (LCDs). The programmability offered by the LCDs offers extremely convenient flexibility.
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Electrolytic redox and electrochemical generated alkaline hydrolysis of hexahydro-1,3,5-trinitro-1,3,5 triazine (RDX) in sand columns.
Environ. Sci. Technol.
PUBLISHED: 09-15-2009
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Sand-packed horizontal flow columns (5 cm i.d. x 65 cm)l were used in laboratory experiments to simulate in situ electrolytic and alkaline hybrid treatment zone for aqueous phase decomposition of RDX. An upgradient cathode and downgradient anode, spaced 35 cm apart were used to create alkaline reducing conditions followed by oxic, acidic conditions to degrade RDX by combination of alkaline hydrolysis and direct electrolysis. A preliminary experiment (25 mg/L RDX influent) with seepage velocity of 30.5 cm/day and current density of 9.9 A/m2 was used to determine the treatment feasibility and the aqueous products of RDX decomposition. Three additional column experiments (0.5 mg/L RDX influent) under the same conditions as the preliminary column were used to observe the treatment process repeatability and the alkaline treatment zone development. The results demonstrated approximately 95% decomposition of RDX in the column with an applied current density of 9.9 A/m2. Aqueous end-products formate, nitrite, and nitrate were detected in the effluent. Approximately 75% of the RDX was destroyed near the cathode, presumably by electrolysis, with 23% decomposed downstream of the cathode by alkaline hydrolysis. The preliminary column pseudo first order alkaline hydrolysis rate coefficient of 10.7 x 10(-3) min(-1) was used to estimate a treatment zone length less than 100 cm for RDX treatment below the EPA drinking water lifetime health advisory of 0.002 mg/L.
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Fourier transform pupil functions for modifying the depth of focus of optical imaging systems.
Appl Opt
PUBLISHED: 09-12-2009
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We use a Fourier transform approach to design pupil functions that modify the axial depth of focus for an optical system. We extend previous research in several ways. We first extend the depth of focus to 4 cm for a 38 cm focal length lens. We show that the transverse size of the focused beam is the same as for an open pupil. We then multiply the pupil function by a circular harmonic window function. The entire depth of focus is now characterized by a vortex beam. Finally we multiply our original pupil function by an edge-enhancing window function. Now the pupil function produces two sharp focus spots at the locations corresponding to the edges of the rectangle function.
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Direct generation of accelerating Airy beams using a 3/2 phase-only pattern.
Opt Lett
PUBLISHED: 09-03-2009
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Accelerated Airy beams have previously been generated using a cubic phase pattern that represents the Fourier transform of the Airy beam. The Fourier transform of this pattern is formed using a system length of 2f, where f is the focal length of the Fourier transform lens. In this work, we directly generate the Airy beam using a 3/2 phase pattern encoded onto an LCD. Experimental results show a deflection that depends on the square of the distance from the LCD and match theoretical predictions. However the system length is much shorter.
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The use of an immunization information system to establish baseline childhood immunization rates and measure contract objectives.
J Public Health Manag Pract
PUBLISHED: 08-26-2009
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Measuring progress toward national immunization objectives at the local level, although difficult, is becoming more feasible owing to statewide immunization information systems. This article describes how a state immunization program expanded the scope of immunization service contracts with local health departments (LHDs) to address the immunization rates among children living within their jurisdictions using the Wisconsin Immunization Registry (WIR) to measure achievement of population-based objectives. By contract year (CY) 2008, 99 percent of Wisconsin LHDs selected population-based contract objectives. In late 2008, the Wisconsin Immunization Program assessed all children at 24 months of age for completeness of the 4:3:1:3:3:1 (diphtheria, tetanus, pertussis/poliovirus/measles-containing vaccine/Haemophilus influenzae type b/hepatitis B/varicella) series by county for each of four CYs, using the WIR. From CY 2005 to CY 2008, LHDs in 61 (86%) of the 71 counties demonstrated increased series completeness rates for the series, and the overall statewide series completeness increased from 58 percent to 64 percent. However, the increases we observed cannot be attributed solely to LHDs acceptance of population-based objectives because controlling for other factors known to influence immunization coverage levels was outside the scope of this case study. We found the WIR to be a powerful tool that can measure immunization coverage among local populations independent of the immunization provider, assess improvement toward contract objectives, and target resources toward pockets of need.
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Fluorinated copolymer nanoparticles for multimodal imaging applications.
Macromol Rapid Commun
PUBLISHED: 07-20-2009
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Nanomaterials have emerged as valuable tools in biomedical imaging techniques. Here, the synthesis and characterization of a novel fluorinated nanoparticle with potential applications as an MRI contrast agent is reported. Particles were synthesized using a free radical polymerization technique. Secondary ion mass spectrometry analysis showed that the particles surface contained fluorinated groups and nitrogen-containing groups. Solid-state NMR spectroscopy suggested the presence of two distinct fluorine resonances, which conforms to the structure of the fluorinated monomer. Ongoing studies aim to evaluate the performance of the nanoparticles as MRI contrast agents both in vitro and in vivo.
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Identifying transfer mechanisms and sources of decabromodiphenyl ether (BDE 209) in indoor environments using environmental forensic microscopy.
Environ. Sci. Technol.
PUBLISHED: 06-19-2009
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Although the presence of polybrominated diphenyl ethers (PBDEs) in house dust has been linked to consumer products, the mechanism of transfer remains poorly understood. We conjecture that volatilized PBDEs will be associated with dust particles containing organic matter and will be homogeneously distributed in house dust. In contrast, PBDEs arising from weathering or abrasion of polymers should remain bound to particles of the original polymer matrix and will be heterogeneously distributed within the dust. We used scanning electron microscopy and othertools of environmental forensic microscopy to investigate PBDEs in dust, examining U.S. and U.K. dust samples with extremely high levels of BDE 209 (260-2600 microg/g), a nonvolatile compound at room temperature. We found that the bromine in these samples was concentrated in widely scattered, highly contaminated particles. In the house dust samples from Boston (U.S.), bromine was associated with a polymer/organic matrix. These results suggest that the BDE 209 was transferred to dust via physical processes such as abrasion or weathering. In conjunction with more traditional tools of environmental chemistry, such as gas chromatography/mass spectrometry (GC/MS), environmental forensic microscopy provides novel insights into the origins of BDE 209 in dust and their mechanisms of transfer from products.
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Generation of accelerating Airy and accelerating parabolic beams using phase-only patterns.
Appl Opt
PUBLISHED: 06-12-2009
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We generate both accelerated Airy and accelerated parabolic beams using phase-only patterns encoded onto a liquid crystal display (LCD). The usual system length is 2f, where f is the focal length of the Fourier transform lens. We develop a compact optical system having a total system length of f. However, the mask must now incorporate the Fresnel diffraction that is not provided by the reduced optical system length. Finally we incorporate the Fourier transform lens onto the mask. We obtain excellent experimental results with a phase-only pattern and a shorter optical system. This approach makes these beams much easier to implement.
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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.