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Find video protocols related to scientific articles indexed in Pubmed.
Forced rotation of nanograting in glass by pulse-front tilted femtosecond laser direct writing.
Opt Express
PUBLISHED: 11-18-2014
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Femtosecond pulse laser with tilted intensity front demonstrates the capability of rotating the writing of nanograting in glass in 3D space. Other than the light polarization, this phenomenon is also associated with the quill-writing effect, which depends on the correlation between the sample movement and the pulse front tilt. This is because a pondermotive force, perpendicular to the tilted intensity plane, can push the excited electron plasma forward towards the pulse front. This behavior further tilts the electrical field plane and eventually result in a forced rotation of nanograting in 3D space.
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Group Sequential Design for Randomized Phase III Trials under the Weibull Model.
J Biopharm Stat
PUBLISHED: 10-17-2014
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Abstract In this paper, a parametric sequential test is proposed under the Weibull model. The proposed test is asymptotically normal with an independent increments structure. The sample size for fixed sample test is derived for the purpose of group sequential trial design. In addition, a multi-stage group sequential procedure is given under the Weibull model by applying the Brownian motion property of the test statistic and sequential conditional probability ratio test methodology.
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Grating-assisted generation of regular two-dimensional multicolored arrays in a tellurite glass.
Opt Express
PUBLISHED: 10-17-2014
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A grating structure was inscribed in a tellurite glass after irradiation with high-repetition rate femtosecond laser pulses. High diffraction efficiency was obtained due to the large refractive index change, which was caused by the precipitation of Te crystals in the laser modified region. Two-dimensional multicolored arrays were generated by cascaded four-wave mixing (CFWM) together with the prefabricated grating structure, which showed much more superior than those induced by beam breakup.
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[The effects of different mechanical ventilation flow model on the peak airway pressure during cardiopulmonary resuscitation].
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 10-16-2014
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To observe the method of mechanical ventilation in the chest compressions during cardiopulmonary resuscitation (CPR), and to explore the influence of the flow pattern selection of square-wave and decelerating-wave on airway pressure of patients.
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Assessment of Carotid Artery Atherosclerotic Disease by Using Three-dimensional Fast Black-Blood MR Imaging: Comparison with DSA.
Radiology
PUBLISHED: 10-07-2014
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Purpose To assess fast three-dimensional ( 3D three-dimensional ) black-blood ( BB black blood ) magnetic resonance (MR) imaging as a noninvasive alternative to intraarterial digital subtraction angiography ( DSA digital subtraction angiography ) at quantifying moderate to severe carotid artery atherosclerotic disease. Materials and Methods Local ethics committee approval and written informed patient consent were obtained for this study. Sixty-five carotid arteries from 52 patients with at least 50% stenosis underwent 3D three-dimensional BB black blood MR imaging and DSA digital subtraction angiography . Quantitative measurements, including stenosis, lesion length, and the presence or absence of plaque ulceration, obtained with the two modalities were independently determined. Sensitivity and specificity, the intraclass correlation coefficient ( ICC intraclass correlation coefficient ), Cohen ?, and Bland-Altman analysis were used to assess the agreement. Results Excellent agreement in measuring luminal stenosis was found between 3D three-dimensional BB black blood MR imaging and DSA digital subtraction angiography ( ICC intraclass correlation coefficient , 0.96; 95% confidence interval [ CI confidence interval ]: 0.93, 0.97). Three-dimensional BB black blood MR imaging was also found to have high sensitivity (91.7%), specificity (96.2%), and agreement (Cohen ?, 0.85; 95% CI confidence interval : 0.66, 0.99) with DSA digital subtraction angiography for detection of ulcers. Good agreement was found between lesion length measured by using 3D three-dimensional BB black blood MR imaging and DSA digital subtraction angiography ( ICC intraclass correlation coefficient , 0.75; 95% CI confidence interval : 0.51, 0.84). However, lesion length measurements by using 3D three-dimensional BB black blood MR imaging were, on average, 4.0 mm longer than those measured by using DSA digital subtraction angiography (P < .001). Conclusion Three-dimensional BB black blood MR imaging is a noninvasive and accurate way to quantify moderate to severe carotid artery atherosclerotic disease. With fast acquisition and large coverage, 3D three-dimensional BB black blood MR imaging has the potential to become an alternative imaging approach in evaluating the severity of atherosclerosis. © RSNA, 2014.
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Influence of bony resection margins and surgicopathological factors on outcomes in limb-sparing surgery for extremity osteosarcoma.
Pediatr Blood Cancer
PUBLISHED: 09-19-2014
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Limb-sparing surgery for osteosarcoma requires taking wide bony resection margins while maximizing preservation of native bone and joint. However, the optimal bony margin and factors associated with recurrence and survival outcomes in these patients are not well established.
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Structural insight into the central element assembly of the synaptonemal complex.
Sci Rep
PUBLISHED: 08-22-2014
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The key step in meiosis is synaptonemal complex formation, which mediates homologous chromosome alignment and synapsis. False pairing between homologous chromosomes produces infertility. Here, we present a crystal structure of the mouse meiosis-specific protein SYCE3, which is a component of the synaptonemal complex central element. Our studies show that functional SYCE3 most likely forms a dimer or higher order oligomer in cells. Furthermore, we demonstrate that the SYCE3 N-helix interacts with the SYCE1 C-helix, which is another central element component. Our results suggest that helical packing may mediate intra- or inter-association of each central element protein component, thereby playing an essential role in forming the synaptonemal complex central elements.
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Esophageal cancer stem cells express PLGF to increase cancer invasion through MMP9 activation.
Tumour Biol.
PUBLISHED: 08-20-2014
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Cancer stem cells (CSCs) are a distinct population in tumors and cause cancer relapse and metastasis. Thus, treating CSCs are believed to be potential to cure rapidly growing and highly metastatic cancers. To date, CSCs in esophageal cancer have not been characterized. In the current study, we detected significant higher levels of placental growth factor (PLGF) and matrix metalloproteinase 9 (MMP9) in the esophageal cancers with metastasis, compared to those without metastasis, in which the expression levels of PLGF and MMP9 strongly correlated with each other. Thus, we used a human esophageal cancer cell line, TE-1, to examine the cross talk of PLGF and MMP9. We found that the levels of PLGF in TE-1 cells positively affected the levels of MMP9, while the levels of MMP9 did not affected the levels of PLGF, suggesting that PLGF may activate MMP9 in esophageal cancer cells. Then, we separated PLGF-positive and PLGF-negative TE-1 cells that had been transfected with a GFP reporter under a PLGF promoter by flow cytometry. We found that PLGF-positive cells grew significantly faster than PLGF-negative cells both in vitro and in vivo in a stereotactical implantation model, suggesting that PLGF-positive cells are likely CSCs in esophageal cancer. Taken together, we demonstrate that PLGF-positive cells appear to be CSCs in esophageal cancer, and they may release PLGF to promote cancer metastasis through MMP9 activation.
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Yb/Er co-doped phosphate all-solid single-mode photonic crystal fiber.
Sci Rep
PUBLISHED: 08-20-2014
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An all-solid Yb(3+)/Er(3+) co-doped single-mode phosphate photonic crystal fiber (PCF) with Watt-level output power and 20 ?m core diameter is demonstrated for the first time. A PCF whose refractivity of the active core is lower than that of the background glass is suggested and theoretically confirmed to be in single-mode operation at 40 ?m core diameter.
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Mesenchymal stem cells genetically modified by lentivirus-mediated interleukin-12 inhibit malignant ascites in mice.
Exp Ther Med
PUBLISHED: 08-19-2014
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The objective of the present study was to investigate the effects of mesenchymal stem cells (MSCs) genetically modified by lentivirus-mediated mouse interleukin-12 (Lenti-mIL-12) in treating malignant ascites in mice. The in vitro chemotactic effect of Lenti-mIL-12-MSC culture supernatant on dendritic cells was investigated using a chemotaxis chamber. Liver cancer H22 and MethA ascites models were constructed. Mice were divided evenly into four groups: Normal saline, MSC, Null and Lenti-mIL-12-MSC. The survival rate, ascites volume and red blood cell number were measured for these groups. The toxicity and side effects of Lenti-mIL-12-MSCs were investigated using visual and microscopy inspections. The results indicated that mIL-12 had a strong chemotactic effect on dendritic cells. mIL-12 was highly expressed in ascites of Lenti-mIL-12-MSC-treated mice. Lenti-mIL-12-MSCs reduced the volume of ascites and the number of red blood cells in ascites and thus increased the survival rate and prolonged the survival duration of the mice. Furthermore, Lenti-mIL-12-MSCs showed no toxicity and side effects on the mice with malignant ascites. In conclusion, the results demonstrated that Lenti-mIL-12-MSCs inhibited the growth of ascites and promoted the survival of tumor-bearing mice, suggesting that Lenti-mIL-12-MSCs exerts a therapeutic effect on malignant ascites by stimulating the immune responses of the mice.
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Initial solid tumor testing (stage 1) of AZD1480, an inhibitor of Janus kinases 1 and 2 by the pediatric preclinical testing program.
Pediatr Blood Cancer
PUBLISHED: 08-17-2014
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AZD1480 is an ATP competitive inhibitor of Janus kinases 1 and 2 (JAK1, 2) that has been shown to inhibit the growth of solid tumor models. This agent was selected for testing the putative role of JAK/STAT signaling in the standard PPTP solid tumor models.
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Lanthanide doped nanoparticles as remote sensors for magnetic fields.
Nanoscale
PUBLISHED: 08-16-2014
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We report the effect of magnetic fields (MFs) on emission Eu-doped NaYF4 nanoparticles. A notable shift in the position of emission bands and the suppressed emission intensity are observed with the MF. These magnetic-optical interactions are explained in terms of the Zeeman effect, enhanced cross-relaxation rate and change of site symmetry.
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Thickness of soft tissue of lower extremities measured with magnetic resonance imaging as a new indicator for staging unilateral secondary lower extremity lymphedema.
Acta Radiol
PUBLISHED: 08-08-2014
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Chronic progressive swelling of the lower extremity due to secondary lower extremity lymphedema (LEL) can affect a patient's quality of life, both physically and psychologically. A feasible and reproducible method for detecting and staging LEL will facilitate decision-making about appropriate management strategies.
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Validity of soft-tissue thickness of calf measured using MRI for assessing unilateral lower extremity lymphoedema secondary to cervical and endometrial cancer treatments.
Clin Radiol
PUBLISHED: 08-06-2014
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To determine whether soft-tissue thickness of the calf measured using MRI could be valid for assessing unilateral lower extremity lymphoedema (LEL) secondary to cervical and endometrial cancer treatments.
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Space-selective precipitation of ZnO crystals in glass by using high repetition rate femtosecond laser irradiation.
Opt Express
PUBLISHED: 08-05-2014
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We report on three-dimensional (3D) precipitation of ZnO crystals inside a silicate glass by a 500 kHz femtosecond pulse laser. The precipitation and distribution of ZnO crystals in glass are confirmed and analyzed by Raman spectra and Raman mapping. Mirco- luminescence is observed in the laser modified region when excited by femtosecond pulse laser or Xenon lamp. The effect of laser average power on the precipitation of the ZnO crystals has also been investigated. The possibility of 3D optical data storage using the observed phenomena is demonstrated.
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Comparison of pain outcomes between two anti-GD2 antibodies in patients with neuroblastoma.
Pediatr Blood Cancer
PUBLISHED: 07-30-2014
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Addition of anti-GD2 antibody ch14.18 to the treatment of neuroblastoma has improved outcomes. The most common side effect of ch14.18 is neuropathic pain, which may in part be complement-mediated. Hu14.18K322A is a humanized anti-GD2 antibody designed to diminish complement activation and induce less pain. We compare the pain outcomes in patients treated with ch14.18 and those treated with hu14.18K322A, and explore dose-dependent relationships between pain scores, opioid requirements, and complement levels in patients treated with hu14.18K322A.
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Intravoxel incoherent motion diffusion-weighted MR imaging of breast cancer at 3.0 tesla: Comparison of different curve-fitting methods.
J Magn Reson Imaging
PUBLISHED: 07-21-2014
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To compare three different curve-fitting methods for intravoxel incoherent motion (IVIM) analysis in breast cancer.
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Topological Engineering of Glass for Modulating Chemical State of Dopants.
Adv. Mater. Weinheim
PUBLISHED: 07-19-2014
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A novel approach to modulating the chemical state of dopants by engineering the topological features of a glass matrix is presented. The method allows selective stabilization of dopants on a wide range of length scales, from dispersed ions to aggregated clusters to nanoparticles, leading to various intriguing optical phenomena, such as great emission enhancement and ultra-broadband optical amplification.
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Enhanced broadband excited upconversion luminescence in Ho-doped glasses by codoping with bismuth.
Opt Lett
PUBLISHED: 07-01-2014
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We report enhanced green and red upconversion (UC) luminescence in Ho3+-doped oxyfluoride germanate glass by introducing bismuth near-infrared active centers as sensitizers. The UC excitation bands at 750 and 970 nm show a full width at half-maximum of 20 and 45 nm, respectively. Energy transfer from sensitizers, the excited-state absorption, and phonon-coupled absorption of Ho3+ jointly contribute to the enhanced UC luminescence. Our approach provides an efficient methodology to broaden the excitation bandwidth of UC luminescent materials, which may have the potential for promising application in solar cells.
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Origin of structural relaxation dependent spectroscopic features of bismuth-activated glasses.
Opt Express
PUBLISHED: 07-01-2014
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For the first time, we studied the effect of structural relaxation on the NIR spectroscopic properties of bismuth-activated germanium glasses below glass transition temperature. Interestingly, distinct change behavior of NIR luminescence is observed at two different heat-treatment temperature ranges corresponding to two different relaxation behavior of glass structure. Besides, when structural modified by partly substituting B(2)O(3) for GeO(2), a narrower and more thermal sensitive luminescence is observed, which is inexplicable by "inhomogeneous broadening" and we tentatively attribute it to a defect-involved reason. Fundamentally the results here not only provide us a deeper insight into the optical property of bismuth-activated materials but also increase our understanding of the glassy state, and practically it delivers some valuable guidance in designing bismuth-activated glasses with superior NIR optical properties.
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The Pepsin Digestibility of Thermal Gel Products Made from White Croaker (Pennahia argentata) Muscle in Associating with Myosin Polymerization Levels.
J. Food Sci.
PUBLISHED: 06-30-2014
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Thermal gels were made from white croaker (Pennahia argentata) surimi at various polymerization levels of myosin heavy chains induced by suwari treatment at 38 °C for various time periods and subsequently heated at 85 °C for 20 min. Myosin heavy chain polymerization levels were also achieved in the presence of microbial transglutaminase (MTG) added at various concentrations in the surimi. The breaking strength and breaking strain rate were markedly increased during suwari treatment up to 60 min in accordance with the increased levels of myosin heavy chain polymerization. MTG enhanced myosin heavy chain polymerization during suwari treatment for 15 and 30 min, resulting in the increase of breaking strength. The solubilization in 8 M urea and pepsin digestibility of these gels as well as angiotensin I-converting enzyme (ACE) inhibitory activity of their pepsin digests were decreased with the increased levels of myosin heavy chain polymerization. These results suggest that myosin heavy chain polymerization affects not only rheological properties of thermal gels but also their functional properties for human health.
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Sample size calculation for the one-sample log-rank test.
Pharm Stat
PUBLISHED: 06-23-2014
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In this paper, an exact variance of the one-sample log-rank test statistic is derived under the alternative hypothesis, and a sample size formula is proposed based on the derived exact variance. Simulation results showed that the proposed sample size formula provides adequate power to design a study to compare the survival of a single sample with that of a standard population. Copyright © 2014 John Wiley & Sons, Ltd.
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Phase I Clinical Trial of Ifosfamide, Oxaliplatin, and Etoposide (IOE) in Pediatric Patients With Refractory Solid Tumors.
J. Pediatr. Hematol. Oncol.
PUBLISHED: 06-20-2014
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Oxaliplatin, although related to cisplatin and carboplatin, has a more favorable toxicity profile and may offer advantages in combination regimens. We combined oxaliplatin, ifosfamide, and etoposide (IOE) and estimated the regimen's maximum tolerated dose (MTD) in children with refractory solid tumors. Dose-limiting toxicity (DLT) and MTD were assessed at 3 dose levels in a 21-day regimen: day 1, oxaliplatin 130 mg/m (consistent dose); days 1 to 3, ifosfamide 1200 mg/m/d (level 0) or 1500 mg/m/d (levels 1 and 2) and etoposide 75 mg/m/d (levels 0 and 1) or 100 mg/m/d (level 2). Course 1 filgrastim/pegfilgrastim was permitted after initial DLT determination, if neutropenia was dose limiting. Seventeen patients received 59 courses. Without filgrastim (n=9), DLT was neutropenia in 2 patients at dose level 1. No DLT was observed after adding filgrastim (n=8). There was no ototoxicity, nephrotoxicity >grade 1, or neurotoxicity >grade 2. One patient experienced a partial response and 9 had stable disease after 2 courses. In conclusion, the IOE regimen was well tolerated. Without filgrastim, neutropenia was dose limiting with MTD at ifosfamide 1200 mg/m/d and etoposide 75 mg/m/d. The MTD with filgrastim was not defined due to early study closure. Filgrastim allowed ifosfamide and etoposide dose escalation and should be included in future studies.
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Power and Sample Size for Randomized Phase III Survival Trials under the Weibull Model.
J Biopharm Stat
PUBLISHED: 06-05-2014
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Abstract Two parametric tests are proposed for designing randomized two-arm phase III survival trials under the Weibull model. The properties of the two parametric tests are compared with the non-parametric log-rank test through simulation studies. Power and sample size formulas of the two parametric tests are derived. The impact on sample size under mis-specification of the Weibull shape parameter is also investigated. The study can be designed by planning the study duration and handling nonuniform entry and loss to follow-up under the Weibull model using either the proposed parametric tests or the well known non-parametric log-rank test.
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Initial testing (stage 1) of the PARP inhibitor BMN 673 by the pediatric preclinical testing program: PALB2 mutation predicts exceptional in vivo response to BMN 673.
Pediatr Blood Cancer
PUBLISHED: 06-04-2014
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BMN 673 is a potent inhibitor of poly-ADP ribose polymerase (PARP) that is in clinical testing with a primary focus on BRCA-mutated cancers. BMN 673 is active both through inhibiting PARP catalytic activity and by tightly trapping PARP to DNA at sites of single strand breaks.
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Solvent extraction of lanthanides and yttrium from aqueous solution with methylimidazole in an ionic liquid.
Dalton Trans
PUBLISHED: 05-23-2014
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1-Methylimidazole (1-MIM) and 2-methylimidazole (2-MIM) are miscible in water and imidazolium based ionic liquids (ILs), and can coordinate with soft metal ions. This paper reports a novel solvent extraction process for trivalent lanthanides and yttrium from aqueous solutions into ILs, which was promoted by a hydrophilic 1-MIM or 2-MIM. Slope analysis confirmed that MIM in ILs formed a 1?:?1 complex with La(3+) and Y(3+) and a 1?:?4 complex with Eu(3+) and Lu(3+), depending on the atomic number of the metal and the metal-ligand interactions that have been characterized by FTIR spectroscopy and ESI-MS. The effect of nitrate concentration on the extraction of lanthanides with 1-MIM in ILs was analysed. It indicated that nitrate anions were involved in the extraction process. Under the same conditions, the extraction of lanthanides with MIM into n-pentanol was carried out. The extractability was by far lower than that obtained in ILs. Both cationic exchange and neutral solvation mechanisms occurred in ILs and only the neutral solvation mechanism occurred in n-pentanol, which were demonstrated by the extraction tests and the structure of extracted species determined by ESI-MS. The competitive extraction in ILs showed good selectivity for lanthanides compared to alkali metals and alkaline earth cations. After extraction, lanthanides could be stripped very easily from the ionic liquid phase with dilute nitric acid. From the temperature dependence data, the thermodynamic parameter values (?H, ?S and ?G) were calculated. The results indicated that the extraction reactions were spontaneous and went through an endothermic process.
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Lanthanide-doped NaGdF4 core-shell nanoparticles for non-contact self-referencing temperature sensors.
Nanoscale
PUBLISHED: 04-25-2014
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We report that non-contact self-referencing temperature sensors can be realized with the use of core-shell nanostructures. These lanthanide-based nanothermometers (NaGdF4:Yb(3+)/Tm(3+)@Tb(3+)/Eu(3+)) exhibit higher sensitivity in a wide range from 125 to 300 K based on two emissions of Tb(3+) at 545 nm and Eu(3+) at 615 nm under near-infrared laser excitation.
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Assessment of in vivo microstructure alterations in gray matter using DKI in internet gaming addiction.
Behav Brain Funct
PUBLISHED: 04-23-2014
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The aim of the current study was to investigate the utility of diffusional kurtosis imaging (DKI) in the detection of gray matter (GM) alterations in people suffering from Internet Gaming Addiction (IGA).
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Initial testing (stage 1) of BAL101553, a novel tubulin binding agent, by the pediatric preclinical testing program.
Pediatr Blood Cancer
PUBLISHED: 04-16-2014
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BAL101553 is a highly water soluble prodrug of BAL27862 that arrests tumor cell proliferation and induces cell death in cancer cells through disruption of the microtubule network. In vitro BAL27862 demonstrated potent activity, with the median relative IC50 (rIC50 ) of 13.8?nM (range 5.4-25.2?nM). The in vitro activity of BAL27862 against the PPTP cell lines is distinctive from that previously described for vincristine. BAL101553 induced significant differences in EFS distribution compared to control in 16 of 30 (53%) solid tumor xenografts and in two of four (67%) of the evaluable ALL xenografts. No objective responses were observed. Pediatr Blood Cancer © 2014 Wiley Periodicals, Inc.
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Phase I trial of a novel anti-GD2 monoclonal antibody, Hu14.18K322A, designed to decrease toxicity in children with refractory or recurrent neuroblastoma.
J. Clin. Oncol.
PUBLISHED: 04-07-2014
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The addition of immunotherapy, including a combination of anti-GD2 monoclonal antibody (mAb), ch14.18, and cytokines, improves outcome for patients with high-risk neuroblastoma. However, this therapy is limited by ch14.18-related toxicities that may be partially mediated by complement activation. We report the results of a phase I trial to determine the maximum-tolerated dose (MTD), safety profile, and pharmacokinetics of hu14.18K322A, a humanized anti-GD2 mAb with a single point mutation (K322A) that reduces complement-dependent lysis.
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Subsequent Malignant Neoplasms in Pediatric Patients Initially Diagnosed With Neuroblastoma.
J. Pediatr. Hematol. Oncol.
PUBLISHED: 03-18-2014
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Most prior studies evaluating subsequent malignant neoplasms (SMNs) in patients with neuroblastoma are restricted to long-term survivors and/or their treatment exposures. This study investigates SMNs in patients diagnosed with neuroblastoma at our institution.
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Population pharmacokinetics of bevacizumab in children with osteosarcoma: implications for dosing.
Clin. Cancer Res.
PUBLISHED: 03-17-2014
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To describe sources of interindividual variability in bevacizumab disposition in pediatric patients and explore associations among bevacizumab pharmacokinetics and clinical wound healing outcomes.
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Recurrent somatic structural variations contribute to tumorigenesis in pediatric osteosarcoma.
Cell Rep
PUBLISHED: 03-03-2014
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Pediatric osteosarcoma is characterized by multiple somatic chromosomal lesions, including structural variations (SVs) and copy number alterations (CNAs). To define the landscape of somatic mutations in pediatric osteosarcoma, we performed whole-genome sequencing of DNA from 20 osteosarcoma tumor samples and matched normal tissue in a discovery cohort, as well as 14 samples in a validation cohort. Single-nucleotide variations (SNVs) exhibited a pattern of localized hypermutation called kataegis in 50% of the tumors. We identified p53 pathway lesions in all tumors in the discovery cohort, nine of which were translocations in the first intron of the TP53 gene. Beyond TP53, the RB1, ATRX, and DLG2 genes showed recurrent somatic alterations in 29%-53% of the tumors. These data highlight the power of whole-genome sequencing for identifying recurrent somatic alterations in cancer genomes that may be missed using other methods.
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Comparative engineering of Escherichia coli for cellobiose utilization: Hydrolysis versus phosphorolysis.
Metab. Eng.
PUBLISHED: 03-01-2014
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Microbial biocatalysts capable of cellobiose assimilation are of interest in bioconversion of cellulosic materials. This study provides a careful comparison in the two mechanisms of cellobiose assimilation, hydrolysis versus phosphorolysis, between two otherwise isogenic E. coli strains. Relative to cells assimilating cellobiose hydrolytically, phosphorolysis cells tolerated common inhibitors better under both anaerobic and aerobic conditions. Additionally, phosphorolysis cells were able to direct the favorable energy metabolism to recombinant protein production, resulting in up to five fold more recombinant proteins. In a mixed sugar fermentation (5% (w/v) cellobiose+5.0% (w/v) xylose), however, xylose utilization in phosphorolysis cells came to a complete halt after only about 60% consumption whereas the hydrolysis cells were able to ferment both sugars to near completion. These results provide insights into the new metabolic engineering strategy. To our best knowledge, this is the first comparison study in E. coli on the two cellobiose assimilation mechanisms.
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Pathologic risk-based adjuvant chemotherapy for unilateral retinoblastoma following enucleation.
J. Pediatr. Hematol. Oncol.
PUBLISHED: 03-01-2014
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There are no standardized diagnostic or treatment guidelines for patients with advanced unilateral retinoblastoma.
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Management of local recurrence of pediatric osteosarcoma following limb-sparing surgery.
Ann. Surg. Oncol.
PUBLISHED: 02-21-2014
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The optimal management of locally recurrent pediatric osteosarcoma is not established, especially after prior limb-sparing surgery. We describe our experience in the management of these patients and identify prognostic indicators of post-recurrence survival.
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Near-infrared emission Ba3(PO4)2:Mn5+ phosphor and potential application in vivo fluorescence imaging.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 02-18-2014
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Fluorescence imaging in the second near-infrared window (NIR-II, 1000-1350 nm) is attracting attention due to negligible tissue scattering and lower tissue autofluorescence, etc. Here, Ba3(PO4)2:Mn(5+) phosphor is prepared via solid state reaction method in air, and NIR emission band peaking at ?1191 nm in the NIR-II region is observed. According to experiment results, Ba3(PO4)2:Mn(5+) phosphor has a great potential for the study of the NIR-II fluorescence imaging in vivo.
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Luminescence properties of red-emission Mg4 Nb2 O9 :Eu(3+) phosphor.
Luminescence
PUBLISHED: 02-14-2014
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Red-emitting Mg4 Nb2 O9 :Eu(3+) phosphor is synthesized via a solid-state reaction method in air, and its crystal structure and luminescence are investigated. The phosphor can be excited efficiently by?~?395?nm light, coupled well with a?~?395?nm near-ultraviolet chip and emits red light at?~?613?nm with sharp spectra due to (5) D0 ???(7) ?F2 transition of the Eu(3+) ion. Mg4 Nb2 O9 :Eu(3+) phosphor sintered at 1350?ºC shows Commission international de I'Eclairage (CIE) chromaticity coordinates of x?=?0.6354, y?=?0.3592, and is a potential red-emitting phosphor candidate for white light-emitting diodes (W-LEDs) under?~?395?nm near-ultraviolet LED chip excitation. Copyright © 2014 John Wiley & Sons, Ltd.
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Abnormal anti-quenching and controllable multi-transitions of Bi3+ luminescence by temperature in a yellow-emitting LuVO4 :Bi3+ phosphor for UV-converted white LEDs.
Chemistry
PUBLISHED: 02-11-2014
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Phosphors with an efficient yellow-emitting color play a crucial role in phosphor-converted white LEDs (pc-WLEDs), but popular yellow phosphors such as YAG:Ce or Eu(2+) -doped (oxy)nitrides cannot smoothly meet this seemingly simple requirement due to their strong absorptions in the visible range. Herein, we report a novel yellow-emitting LuVO(4) :Bi(3+) phosphor that can solve this shortcoming. The emission from LuVO(4) :Bi(3+) shows a peak at 576?nm with a quantum efficiency (QE) of up to 68?%, good resistance to thermal quenching (T(50?%) =573?K), and no severe thermal degradation after heating-cooling cycles upon UV excitation. The yellow emission, as verified by X-ray photoelectron spectra (XPS), originates from the ((3)P(0),(3)P(1))?(1) S0 transitions of Bi(3+). Increasing the temperature from 10 to 300?K produces a temperature-dependent energy-transfer process between VO(4)(3-) groups and Bi(3+), and further heating of the samples to 573?K intensifies the emission. However, it subsequently weakens, accompanied by blueshifts of the emission peaks. This abnormal anti-thermal quenching can be ascribed to temperature-dependent energy transfer from VO(4)(3-) groups to Bi(3+), a population redistribution between the excited states of (3)P(0) and (3)P(1) upon thermal stimulation, and discharge of electrons trapped in defects with a trap depth of 359?K. Device fabrication with the as-prepared phosphor LuVO(4) :Bi(3+) has proved that it can act as a good yellow phosphor for pc-WLEDs.
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Anti-stokes fluorescent probe with incoherent excitation.
Sci Rep
PUBLISHED: 01-23-2014
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Although inorganic anti-Stokes fluorescent probes have long been developed, the operational mode of today's most advanced examples still involves the harsh requirement of coherent laser excitation, which often yields unexpected light disturbance or even photon-induced deterioration during optical imaging. Here, we demonstrate an efficient anti-Stokes fluorescent probe with incoherent excitation. We show that the probe can be operated under light-emitting diode excitation and provides tunable anti-Stokes energy shift and decay kinetics, which allow for rapid and deep tissue imaging over a very large area with negligible photodestruction. Charging of the probe can be achieved by either X-rays or ultraviolet-visible light irradiation, which enables multiplexed detection and function integration with standard X-ray medical imaging devices.
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Determination of Meserine, a new candidate for Alzheimer's disease in mice brain by liquid chromatography-tandem mass spectrometry and its application to a pharmacokinetic and tissue distribution study.
Anal Bioanal Chem
PUBLISHED: 01-21-2014
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A rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determination of Meserine ((-)-meptazinol phenylcarbamate), a novel potent inhibitor of acetylcholinesterase (AChE), was developed, validated, and applied to a pharmacokinetic study in mice brain. The lower limit of quantification (LLOQ) was 1 ng mL(-1) and the linear range was 1-1,000 ng mL(-1). The analyte was eluted on a Zorbax SB-Aq column (2.1?×?100 mm, 3.5 ?m) with the mobile phase composed of methanol and water (70:30, v/v, aqueous phase contained 10 mM ammonium formate and 0.3% formic acid) using isocratic elution, and monitored by positive electrospray ionization in multiple reaction monitoring (MRM) mode. The flow rate was 0.25 mL min(-1). The injection volume was 5 ?L and total run time was 4 min. The relative standard deviation (RSD) of intraday and interday variation was 2.49-7.81 and 3.01-7.67%, respectively. All analytes were stable after 4 h at room temperature and 6 h in autosampler. The extraction recoveries of Meserine in brain homogenate were over 90%. The main brain pharmacokinetic parameters obtained after intranasal administration were T max?=?0.05 h, C max?=?462.0?±?39.7 ng g(-1), T 1/2?=?0.4 h, and AUC(0-?)?=?283.1?±?9.1 ng h g(-1). Moreover, Meserine was distributed rapidly and widely into brain, heart, liver, spleen, lung, and kidney tissue. The method is validated and could be applied to the pharmacokinetic and tissue distribution study of Meserine in mice.
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Initial testing (stage 1) of the investigational mTOR kinase inhibitor MLN0128 by the pediatric preclinical testing program.
Pediatr Blood Cancer
PUBLISHED: 01-21-2014
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MLN0128 is an investigational small molecule ATP-competitive inhibitor of the serine/threonine kinase mTOR. MLN0128 was tested against the in vitro panel at concentrations ranging from 0.1?nM to 1??M and against the PPTP in vivo panels at a dose of 1?mg/kg administered orally daily?×?28. In vitro the median relative IC(50) concentration was 19?nM. In vivo MLN0128 induced significant differences in EFS in 24/31 (77%) solid tumor models, but 0/7 ALL xenografts. The modest activity observed for MLN0128 against the PPTP preclinical models is similar to that previously reported for another TOR kinase inhibitor.
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Non-Gaussian water diffusion kurtosis imaging of prostate cancer.
Magn Reson Imaging
PUBLISHED: 01-13-2014
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To evaluate the non-Gaussian water diffusion properties of prostate cancer (PCa) and determine the diagnostic performance of diffusion kurtosis (DK) imaging for distinguishing PCa from benign tissues within the peripheral zone (PZ), and assessing tumor lesions with different Gleason scores.
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A long persistent phosphor based on recombination centers originating from Zn imperfections.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 01-07-2014
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The recombination luminescence from Zn imperfections has been extensively investigated; however, there have been few reports on the long persistent luminescence of Zn imperfections as emitting centers. Here, we observed a long persistent luminescence in blue-white visible region from 6 ZnO:3 GeO2:Al2O3 phosphor with Zn imperfections as emitting centers. Persistent luminescence could be observed beyond 2h with naked eyes. The properties of traps were also elaborated by the measurements of thermo-luminescence spectra and photo-stimulated luminescence decay curves. Furthermore, a long persistent phosphor with warm white color was developed by doping Cr(3+) into 6 ZnO:3 GeO2:Al2O3 phosphor.
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Initial testing (stage 1) of the notch inhibitor PF-03084014, by the pediatric preclinical testing program.
Pediatr Blood Cancer
PUBLISHED: 01-06-2014
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PF-03084014, a ?-secretase inhibitor, was tested against the PPTP in vitro cell line panel (1.0?nM to 10??M) and against the in vivo xenograft panels (administered orally twice daily on Days 1-7 and 15-21). PF-03084014 demonstrated limited in vitro activity, with no cell line achieving ?50% inhibition. PF-03084014 induced significant differences in EFS distribution in 14 of 35 (40%) solid tumor xenografts, and 1 of 9 ALL xenografts (which lacked a NOTCH1 mutation), but objective responses were not observed. PF-03084014 demonstrated limited single agent activity in vitro and in vivo against the pediatric preclinical models studied.
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Disrupted brain functional network in internet addiction disorder: a resting-state functional magnetic resonance imaging study.
PLoS ONE
PUBLISHED: 01-01-2014
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Internet addiction disorder (IAD) is increasingly recognized as a mental health disorder, particularly among adolescents. The pathogenesis associated with IAD, however, remains unclear. In this study, we aim to explore the encephalic functional characteristics of IAD adolescents at rest using functional magnetic resonance imaging data. We adopted a graph-theoretic approach to investigate possible disruptions of functional connectivity in terms of network properties including small-worldness, efficiency, and nodal centrality on 17 adolescents with IAD and 16 socio-demographically matched healthy controls. False discovery rate-corrected parametric tests were performed to evaluate the statistical significance of group-level network topological differences. In addition, a correlation analysis was performed to assess the relationships between functional connectivity and clinical measures in the IAD group. Our results demonstrate that there is significant disruption in the functional connectome of IAD patients, particularly between regions located in the frontal, occipital, and parietal lobes. The affected connections are long-range and inter-hemispheric connections. Although significant alterations are observed for regional nodal metrics, there is no difference in global network topology between IAD and healthy groups. In addition, correlation analysis demonstrates that the observed regional abnormalities are correlated with the IAD severity and behavioral clinical assessments. Our findings, which are relatively consistent between anatomically and functionally defined atlases, suggest that IAD causes disruptions of functional connectivity and, importantly, that such disruptions might link to behavioral impairments.
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Association of radiologic findings with mortality in patients with avian influenza H7N9 pneumonia.
PLoS ONE
PUBLISHED: 01-01-2014
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The novel H7N9 virus causes severe illness, including pneumonia and acute respiratory distress syndrome, with high rates of mortality. We investigated the association of initial radiologic characteristics obtained at admission with clinical outcomes in patients with avian influenza H7N9 pneumonia.
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Low-temperature growth of near-infrared luminescent Bi-doped SiOxNy thin films.
Opt Lett
PUBLISHED: 12-11-2013
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Bi-doped siliconoxynitride (SiON:Bi) thin films were prepared by a sputtering method and the photoluminescence (PL) properties were studied. Without any thermal treatments, broad Bi-related luminescence was observed in the near-infrared (NIR) range. The luminescence efficiency depended strongly on the film composition. It was found that N atoms play a crucial role for the formation of Bi NIR luminescence centers. The effect of annealing on the luminescence efficiency was also studied. The optimum annealing temperature to have the largest number of Bi NIR luminescence centers depended strongly on the film composition and it was lower for films with lower N concentration. The PL excitation spectra revealed that two different Bi NIR luminescence centers exist in the films.
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The Role of PET/CT in Assessing Pulmonary Nodules in Children With Solid Malignancies.
AJR Am J Roentgenol
PUBLISHED: 11-23-2013
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OBJECTIVE. The purpose of this article is to assess the feasibility and utility of PET/CT in distinguishing benign from malignant pulmonary nodules in patients with solid childhood malignancies. SUBJECTS AND METHODS. This prospective study was conducted between March 2008 and August 2010. We enrolled 25 subjects 21 years old or younger with solid childhood malignancies and at least one pulmonary nodule measuring 0.5-3.0 cm. PET/CT was performed within 3 weeks of diagnostic chest CT. Three panels of three reviewers each reviewed diagnostic CT only (panel 1), PET/CT only (panel 2), or diagnostic CT and PET/CT concurrently (panel 3) and predicted each nodules histologic diagnosis as benign, malignant, or indeterminate. Interreviewer agreement was assessed with the kappa statistic. Using nodule biopsy or clinical follow-up as reference standards, the sensitivity, specificity, and accuracy for each panel was assessed. Logistic regression was used to assess the nodules maximum standardized uptake value (SUVmax) association with its histologic diagnosis. RESULTS. There were 75 nodules with a median size of 0.74 cm (range, 0.18-2.38 cm); 48 nodules were malignant. Sensitivity was 85% (41/48) for panel 1, 60% (29/48) for panel 2, and 67% (32/48) for panel 3. All panels had poor specificities. Interreviewer agreement was moderate for panel 1 (0.43) and poor for panels 2 (0.22) and 3 (0.33). SUVmax was a significant predictor of histologic diagnosis (p = 0.004). CONCLUSION. PET/CT assessment of pulmonary nodules is feasible in children with solid malignancies but may not reliably improve our ability to predict a nodules histologic diagnosis. The SUVmax may improve the performance of PET/CT in this setting.
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Photoinduced luminescent carbon nanostructures with ultra-broadly tailored size ranges.
Nanoscale
PUBLISHED: 10-22-2013
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Carbon nanoparticles (CNPs), hollow CNPs, nanodiamonds, and hybrid graphene spheres (HGSPs) are produced by using fs laser ablation in solution. These carbon nanostructures emit tunable photoluminescence and two-photon luminescence. The photoinduced layer-by-layer assembly of graphene nanosheets is observed to form HGSPs with tailored broadly-ranged sizes for the first time.
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2.7 ?m emission in Er3+:CaF2 nanocrystals embedded oxyfluoride glass ceramics.
Opt Lett
PUBLISHED: 10-10-2013
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Using conventional melt-quenching and subsequent thermal treatment, Er(3+) doped CaF(2) transparent glass ceramic (GC) was prepared. X-ray diffraction and high-resolution transmission electron microscopy confirmed the formation and microstructure of CaF(2) nanocrystals in glass. An energy-dispersive spectrometer was used to investigate the distribution of Er(3+) ions and CaF(2) nanocrystals in glass. It was found that Er(3+) ions prefer to concentrate in the CaF(2) nanocrystals rather than in a glass matrix, and the amount of Er(3+) ions plays a key role in the formation of CaF(2) nanocrystals in a glass matrix with the Er(3+) ions as nucleating agent. An intense 2.7 ?m emission due to Er(3+): I(11/2)4 ? I(13/2)4 was achieved upon excitation at 980 nm with a laser diode, while the 2.7 ?m emission can be neglected in the as-prepared glass counterpart, which confirmed the incorporation of Er(3+) ions into CaF(2) nanocrystals. An obvious enhancement of 2.7 ?m emerged in the GC doped with 3% Er(3+) and heat-treated at 620 °C.
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Temperature dependent red luminescence from a distorted Mn4+ site in CaAl4O7:Mn4+.
Opt Express
PUBLISHED: 08-14-2013
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Thermal luminescence quenching behavior of a phosphor is essential for application in phosphor converted white light emitting diodes (pc-WLEDs) because the phosphor layer can be heated up to 473K in a working high power WLEDs. Here, we have confirmed indeed a red luminescence of Mn(4+) substituting for calcium sites rather than tetrahedral aluminum sites in CaAl(4)O(7):Mn which can be synthesized in pure phase even with boron acid as flux, and examined the low and high temperature luminescent properties in the range of 10 to 500K. We have revealed as well as thermal quenching mechanism that distorted octahedral Mn(4+) sites suffer severe thermal quenching. This work, thus, hints a strategy to find a new Mn(4+) phosphor with better resistance to thermal impact in the future.
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Ultra-broadband infrared luminescence of Bi-doped thin-films for integrated optics.
Opt Express
PUBLISHED: 08-14-2013
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Ultra-broadband infrared luminescence has been observed in bismuth (Bi)-doped germanate thin-films prepared by pulsed laser deposition. The films are compatible with various types of substrates, including conventional dielectrics (LaAlO(3), silica) and semiconductors (Si, GaAs). The emission peak position of the films can be finely tuned by changing oxygen partial pressure during the deposition, while the excitation wavelength locates from ultra-violet to near-infrared regions. The physical mechanism behind the observed infrared luminescence of the Bi-doped films, differing from that of the as-made glass, is discussed.
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Polarization dependence of the self-organized microgratings induced in SrTiO3 crystal by a single femtosecond laser beam.
Opt Express
PUBLISHED: 08-14-2013
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In this paper, self-organized microgratings are fabricated in SrTiO(3) crystal just by scanning the focus of a tightly-focused linearly-polarized femtosecond laser beam to form a single line. The polarization direction of the laser beam is rotated by a ?/2 waveplate to check the effect of the polarization azimuth on the micrograting morphology. Fourier analyzing of the microscopic images of the microgratings indicates that the polarization plane azimuth of the laser beam does have influence on the microgratings in the aspects of groove orientation and groove spacing. A possible mechanism of polarization dependence is also proposed.
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Luffa-sponge-like glass-TiO2 composite fibers as efficient photocatalysts for environmental remediation.
ACS Appl Mater Interfaces
PUBLISHED: 08-05-2013
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Structural design of photocatalysts is of great technological importance for practical applications. A rational design of architecture can not only promote the synthetic performance of photocatalysts but also bring convenience in their application procedure. Nanofibers have been established as one of the most ideal architectures of photocatalysts. However, simultaneous optimization of the photocatalytic efficiency, mechanical strength, and thermal/chemical tolerance of nanofibrous photocatalysts remains a big challenge. Here, we demonstrate a novel design of TiO2-SiO2 composite fiber as an efficient photocatalyst with excellent synthetic performance. Core-shell mesoporous SiO2 fiber with high flexibility was employed as the backbone for supporting ultrasmall TiO2 nanowhiskers of the anatase phase, constructing core@double-shell fiber with luffa-sponge-like appearance. Benefitting from their continuously long fibrous morphology, highly porous structure, and completely inorganic nature, the TiO2-SiO2 composite fibers simultaneously possess high photocatalytic reactivity, good flexibility, and excellent thermal and chemical stability. This novel architecture of TiO2-SiO2 glass composite fiber may find extensive use in the environment remediation applications.
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Initial testing (Stage 1) of TAK-701, a humanized hepatocyte growth factor binding antibody, by the pediatric preclinical testing program.
Pediatr Blood Cancer
PUBLISHED: 07-22-2013
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TAK-701 is a humanized antibody that binds hepatocyte growth factor (HGF), thus suppressing c-Met transduced signaling and c-Met dependent proliferation and migration of tumor cells. Six childhood solid tumor xenografts were selected for evaluating TAK-701 based on immunochemical detection of HGF/c-Met autocrine signaling [i.e., pMet(Tyr1349) and HGF positive]. TAK-701 was tested using a dose of 30?mg/kg administered by the intraperitoneal (IP) route twice weekly for 4 weeks. TAK-701 did not induce significant differences in EFS distribution in treated tumors compared to control tumors. Objective responses were not observed in any of the tested solid tumor xenografts. Pediatr Blood Cancer 2014;61:380-382. © 2013 Wiley Periodicals, Inc.
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Yellow-to-orange emission from B2+-doped RF2 (R = Ca and Sr) phosphors.
Opt Express
PUBLISHED: 07-12-2013
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RF2:Bi (R = Ca and Sr) phosphors were synthesized by solid state reaction method in air and their luminescence properties were investigated. Broad yellow-to-orange emissions peaking at ~550 nm (CaF2:Bi) and ~600 nm (SrF2:Bi) were observed under ~260 nm excitation. The emission centers inRF2:Bi (R = Ca and Sr) phosphors are Bi2+ ions, and the excitation and emission bands of RF2:Bi (R = Ca and Sr) phosphors can be attributed to 2P 1/2 ? 2S 1/2 and 2P 3/2(1) ? 2P 1/2 transitions of Bi2+ ions, respectively. The phosphors are promising for application in lighting due to broad yellow-to-orange emission.
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Fabrication of polarization-dependent light attenuator in fused silica using a low-repetition-rate femtosecond laser.
Opt Lett
PUBLISHED: 07-02-2013
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In this Letter, we have demonstrated the direct writing of polarization-dependent light attenuator inside fused silica by tailoring 1 kHz femtosecond (fs) laser induced self-organized nanogratings. Optical birefringence was observed to vary with the polarization plane azimuth of the fs laser and scanning direction. The formation of self-organized nanogratings was confirmed by scanning electron microscopy observation. A polarization-dependent light attenuator was fabricated by forming a plane consisting of nanograting lines inside fused silica by scanning the fs laser. The attenuation efficiency was improved by forming a multilayer nanograting structure. The technique may find important applications in micro-optical devices.
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LIGHT regulates the adipogenic differentiation of mesenchymal stem cells.
J. Cell. Biochem.
PUBLISHED: 06-05-2013
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LIGHT is a cytokine belonging to the TNF family. This cytokine has been extensively defined in its role on T-cell regulation and dendritic cell maturation. It also exhibits the role in liver regeneration. We recently identified its role in regulation of hematopoietic stem cell differentiation. However, the question whether this cytokine regulates mesenchymal stem cells (MSCs) proliferation and/or differentiation remains unknown. In this study, we observed that MSCs express LT-?R but not HVEM. PCR analysis show LIGHT mRNA is undectable in MSCs. LIGHT did promote neither MSCs proliferation nor migration. However, LIGHT promoted MSCs differentiation into adipocyte which was confirmed by Oil Red O Staining Assay. Since either MSCs or adipocytes are the major cell population in bone marrow niche, we then suggest that LIGHT regulate bone marrow niche, such as MSCs differentiation.
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Enhanced luminescence in SrMgAl(x)O(17±?):yMn4+ composite phosphors.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 05-16-2013
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Red-emitting SrMgAlxO17±?:yMn(4+) composite phosphors (x=10-100; y=0.05-4.0 mol%) are synthesized by solid-state reaction method in air. Addition of Al2O3 leads to the formation of two concomitant phases, i.e., SrMgAl10O17 and Al2O3 phases in the composite phosphor. Red emission from Mn(4+) ions in the composite phosphors is greatly enhanced due to multiple scattering and absorption of excitation light between SrMgAl10O17 and Al2O3 phases. SrMgAlxO17±?:yMn(4+) composite phosphors would be a promising candidate as red phosphor in the application of a 397 nm near UV-based W-LED.
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Fabrication of silica nano/micro-fibers doped with one-dimensional assembly of silver nanoparticles.
J Nanosci Nanotechnol
PUBLISHED: 05-08-2013
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Nano/micro fibers doped with metal nanocrystals are of great interest both theorectically and practically. Nevertheless, the ordered assembly of metal nanocrystals with desired patterns in nano/micro fibers still remains a big challenge, which constrains the further development of the performance of the material. In this investigation, we propose a facile strategy based on the sol-gel and coaxial electrospinning technique to fabricate silica submicron fibers incorporating ordered 1D array of silver nanoparticles. The silver nanoparticles align strictly in a head-to-tail manner in silica fibers, and their size, shape and population are conveniently controlled through tailoring the properties of the precursor solutions and the electrospinning parameters. Therefore, the plasmon property of the obtained fibers is tuned with great freedom. The fabrication method applied here holds great potential for low-cost preparation of metal/glass composite fibers for nano/micro optical applications in general.
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Physical and chemical characterization of ashes from a municipal solid waste incinerator in China.
Waste Manag Res
PUBLISHED: 04-25-2013
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In this study we analyzed the characteristics of bottom and fly ashes from a municipal solid waste incinerator in China. The physical properties of particle size distribution and morphology were evaluated. At the chemical level, the chemical composition, heavy metal leaching behavior and BCR sequential extraction procedure (the Community Bureau of Reference, now the European Union Measurement and Testing Programme) were determined. The main mineralogical crystalline phases in raw and leached bottom and fly ashes were also identified. For the bottom ashes, the concentration of heavy metals showed a slight decrease with an increase in particle size, and most of the heavy metal concentrations in fly ashes were higher than those in bottom ashes. The results of the toxicity characteristic leaching procedure indicated that, among the metals, the concentrations of lead (Pb) and copper (Cu) in fly ash leachate exceeded thresholds, while the concentrations of studied heavy metals in bottom ash leachate were all below the regulatory limit. The BCR results indicated that more easily mobilized forms (acid exchangeable) were predominant for cadmium and zinc; in contrast, the largest amount of Pb, Cu and manganese were associated with iron/manganese oxide, organic matter/sulfide fractions, or were residual.
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Ultrasensitive polarized up-conversion of Tm(3+)-Yb3+ doped ?-NaYF4 single nanorod.
Nano Lett.
PUBLISHED: 04-25-2013
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Up-conversion luminescence in rare earth ions (REs) doped nanoparticles has attracted considerable research attention for the promising applications in solid-state lasers, three-dimensional displays, solar cells, biological imaging, and so forth. However, there have been no reports on REs doped nanoparticles to investigate their polarized energy transfer up-conversion, especially for single particle. Herein, the polarized energy transfer up-conversion from REs doped fluoride nanorods is demonstrated in a single particle spectroscopy mode for the first time. Unique luminescent phenomena, for example, sharp energy level split and singlet-to-triplet transitions at room temperature, multiple discrete luminescence intensity periodic variation with polarization direction, are observed upon excitation with 980 nm linearly polarized laser. Furthermore, nanorods with the controllable aspect ratio and symmetry are fabricated for analysis of the mechanism of polarization anisotropy. The comparative experiments suggest that intraions transition properties and crystal local symmetry dominate the polarization anisotropy, which is also confirmed by density functional theory calculations. Taking advantage of the REs based up-conversion, potential application in polarized microscopic multi-information transportation is suggested for the polarization anisotropy from REs doped fluoride single nanorod or nanorod array.
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Voxel-level comparison of arterial spin-labeled perfusion magnetic resonance imaging in adolescents with internet gaming addiction.
Behav Brain Funct
PUBLISHED: 04-23-2013
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Although recent studies have clearly demonstrated functional and structural abnormalities in adolescents with internet gaming addiction (IGA), less is known about how IGA affects perfusion in the human brain. We used pseudocontinuous arterial spin-labeling (ASL) perfusion functional magnetic resonance imaging (fMRI) to measure the effects of IGA on resting brain functions by comparing resting cerebral blood flow in adolescents with IGA and normal subjects.
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Near-infrared to mid-infrared photoluminescence of Bi2O3-GeO2 binary glasses: comment.
Opt Lett
PUBLISHED: 04-19-2013
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We discuss the origin of near- to mid-infrared emissions in Bi-doped oxide glasses recently reported [Opt. Lett.37, 4260 (2012)]. Our detailed analysis indicates that the near- to mid-infrared emissions in the range of 1200-3000 nm peaking at ~2500, 2650, and 2700 nm do not result from Bi active centers in the oxide matrix but are due to the selective atmospheric absorption of thermal radiation induced by laser irradiation.
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Synthesis and luminescence mechanism of multicolor-emitting g-C3N4 nanopowders by low temperature thermal condensation of melamine.
Sci Rep
PUBLISHED: 04-04-2013
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Graphite like C3N4 (g-C3N4) was synthesized facilely via the low temperature thermal condensation of melamine between 300-650°C. The results showed that the products maintained as melamine when the temperature is below 300°C. With the increase of temperature, the products were transformed into carbon nitride and amorphous g-C3N4 successively. The morphology of products was changed from spherical nanoparticles of melamine into layer carbon nitride and g-C3N4 with the increase of temperature. The photoluminescence spectra showed that the carbon nitride products have continuous tunable photoluminescence properties in the visible region with increasing temperature. With the help of steady state, transient state time-resolved photoluminescence spectra and Raman microstructural characterization, a novel tunable photoluminescence mechanism was founded systematically, which is mainly related to the two dimensional ?-conjugated polymeric network and the lone pair of the carbon nitride.
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Mycorrhizas alter nitrogen acquisition by the terrestrial orchid Cymbidium goeringii.
Ann. Bot.
PUBLISHED: 03-26-2013
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Orchid mycorrhizas exhibit a unique type of mycorrhizal symbiosis that occurs between fungi and plants of the family Orchidaceae. In general, the roots of orchids are typically coarse compared with those of other plant species, leading to a considerably low surface area to volume ratio. As a result, orchids are often ill-adapted for direct nutrient acquisition from the soil and so mycorrhizal associations are important. However, the role of the fungal partners in the acquisition of inorganic and organic N by terrestrial orchids has yet to be clarified.
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Phase transformation and intense 2.7??m emission from Er3+ doped YF3/YOF submicron-crystals.
Sci Rep
PUBLISHED: 03-15-2013
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Yttrium fluoride YF3:Er(3+) and yttrium oxyfluoride YOF:Er(3+) submicron-crystals with mid-infrared fluorescent emissions were synthesized for the first time. The rhombohedral phase YOF submicron-crystals were synthesized by the crystalline phase transformation from pure orthorhombic YF3 submicron-crystals, which were prepared by co-precipitation method. The composition and morphology were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM), which showed that submicron-crystals were quasi-spherical with the particle size of ~400?nm. A novel formation mechanism of YOF submicron-crystals was proposed. Photoluminescence (PL) spectra indicated the 2.7??m emission of Er(3+) has remarkably enhanced with the increase of Er(3+) doping concentration, and a novel dynamic circulatory energy transfer mechanism was proposed. Fourier transform infrared spectra (FTIR) were used to demonstrate the change of hydroxyl content. These oxyfluoride submicron-crystals provide a new material for nano/submicron-crystals-glass composites, and open a brand new field for the realization of mid-infrared micro/nano-lasers.
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Broadband downshifting luminescence in Cr³??Yb³? codoped garnet for efficient photovoltaic generation.
Opt Express
PUBLISHED: 03-14-2013
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The Cr³??Yb³? codoped YAG crystals were synthesized by the solid state reaction method, in which the intense near-infrared emission around 1000 nm originated from Yb³? ²F?/? ?²F?/? transition was obtained due to the efficient energy transfer from Cr³? to Yb³?. The stable and transient spectral measurements revealed that the phonon assistant energy transfer process is responsible for the energy transfer from Cr³? to Yb³? upon both the excitations of Cr³?: ?T? and ?T?> energy levels. Due to the effective absorption of Cr³? in the visible region in YAG and the efficient energy transfer to Yb³?, this material can be developed as spectral convertors to improve silicon solar cell photovoltaic conversion efficiency.
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