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Find video protocols related to scientific articles indexed in Pubmed.
Can Marginal Rates of Substitution Be Inferred From Happiness Data? Evidence from Residency Choices.
Am Econ Rev
PUBLISHED: 11-19-2014
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We survey 561 students from U.S. medical schools shortly after they submit choice rankings over residencies to the National Resident Matching Program. We elicit (a) these choice rankings, (b) anticipated subjective well-being (SWB) rankings, and (c) expected features of the residencies (such as prestige). We find substantial differences between choice and anticipated-SWB rankings in the implied tradeoffs between residency features. In our data, evaluative SWB measures (life satisfaction and Cantril's ladder) imply tradeoffs closer to choice than does affective happiness (even time-integrated), and as close as do multi-measure SWB indices. We discuss implications for using SWB data in applied work.
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Assessment of hospital daily cleaning practices using ATP bioluminescence in a developing country.
Braz J Infect Dis
PUBLISHED: 09-01-2014
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Visual assessment of surfaces may not be enough to document the level of cleanliness in the hospital setting. It is necessary to introduce quantitative methods to document the results of this practice.
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Potential biases in the classification, analysis and interpretations in cross-sectional study: commentaries - surrounding the article "resting heart rate: its correlations and potential for screening metabolic dysfunctions in adolescents".
BMC Pediatr
PUBLISHED: 04-25-2014
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Resting heart rate reflects sympathetic nerve activity. A significant association between resting heart rate (HR) and all causes of cardiovascular mortality has been reported by some epidemiologic studies. Despite suggestive evidence, resting heart rate (RHR) has not been formally explored as a prognostic factor and potential therapeutic outcome and, therefore, is not generally accepted in adolescents.
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A novel external fixator used to treat open comminuted fractures of the middle and distal phalanges with concomitant FDP avulsion injury.
Tech Hand Up Extrem Surg
PUBLISHED: 04-25-2014
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The use of external fixators for treating comminuted hand fractures has become popular with commercially available or handmade fixators assembled in the operating theater. We present a case of a Zone I flexor digitorum profundus (FDP) avulsion fracture that was complicated by the presence of open, comminuted fractures of the distal and middle phalanges. The injury was treated using an external fixator constructed in the operating theater from readily available materials and with a 4-strand pullout suture technique tied over a button to repair the FDP avulsion. This technique facilitated treatment of the comminuted and contaminated fractures while allowing reconstruction of the Zone I FDP injury and allowing relatively early mobilization of the FDP repair.
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Miscalibrations in judgements of attractiveness with cosmetics.
Q J Exp Psychol (Hove)
PUBLISHED: 04-22-2014
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Women use cosmetics to enhance their attractiveness. How successful they are in doing so remains unknown--how do men and women respond to cosmetics use in terms of attractiveness? There are a variety of miscalibrations where attractiveness is concerned--often, what one sex thinks the opposite sex finds attractive is incorrect. Here, we investigated observer perceptions about attractiveness and cosmetics, as well as their understanding of what others would find attractive. We used computer graphic techniques to allow observers to vary the amount of cosmetics applied to a series of female faces. We asked observers to optimize attractiveness for themselves, for what they thought women in general would prefer, and what they thought men in general would prefer. We found that men and women agree on the amount of cosmetics they find attractive, but overestimate the preferences of women and, when considering the preferences of men, overestimate even more. We also find that models' self-applied cosmetics are far in excess of individual preferences. These findings suggest that attractiveness perceptions with cosmetics are a form of pluralistic ignorance, whereby women tailor their cosmetics use to an inaccurate perception of others' preferences. These findings also highlight further miscalibrations of attractiveness ideals.
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Cryptochrome-dependent magnetic field effect on seizure response in Drosophila larvae.
Sci Rep
PUBLISHED: 03-28-2014
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The mechanisms that facilitate animal magnetoreception have both fascinated and confounded scientists for decades, and its precise biophysical origin remains unclear. Among the proposed primary magnetic sensors is the flavoprotein, cryptochrome, which is thought to provide geomagnetic information via a quantum effect in a light-initiated radical pair reaction. Despite recent advances in the radical pair model of magnetoreception from theoretical, molecular and animal behaviour studies, very little is known of a possible signal transduction mechanism. We report a substantial effect of magnetic field exposure on seizure response in Drosophila larvae. The effect is dependent on cryptochrome, the presence and wavelength of light and is blocked by prior ingestion of typical antiepileptic drugs. These data are consistent with a magnetically-sensitive, photochemical radical pair reaction in cryptochrome that alters levels of neuronal excitation, and represent a vital step forward in our understanding of the signal transduction mechanism involved in animal magnetoreception.
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Detecting abnormalities in choroidal vasculature in a mouse model of age-related macular degeneration by time-course indocyanine green angiography.
J Vis Exp
PUBLISHED: 03-19-2014
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Indocyanine Green Angiography (or ICGA) is a technique performed by ophthalmologists to diagnose abnormalities of the choroidal and retinal vasculature of various eye diseases such as age-related macular degeneration (AMD). ICGA is especially useful to image the posterior choroidal vasculature of the eye due to its capability of penetrating through the pigmented layer with its infrared spectrum. ICGA time course can be divided into early, middle, and late phases. The three phases provide valuable information on the pathology of eye problems. Although time-course ICGA by intravenous (IV) injection is widely used in the clinic for the diagnosis and management of choroid problems, ICGA by intraperitoneal injection (IP) is commonly used in animal research. Here we demonstrated the technique to obtain high-resolution ICGA time-course images in mice by tail-vein injection and confocal scanning laser ophthalmoscopy. We used this technique to image the choroidal lesions in a mouse model of age-related macular degeneration. Although it is much easier to introduce ICG to the mouse vasculature by IP, our data indicate that it is difficult to obtain reproducible ICGA time course images by IP-ICGA. In contrast, ICGA via tail vein injection provides high quality ICGA time-course images comparable to human studies. In addition, we showed that ICGA performed on albino mice gives clearer pictures of choroidal vessels than that performed on pigmented mice. We suggest that time-course IV-ICGA should become a standard practice in AMD research based on animal models.
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The HIV-Brazil cohort study: design, methods and participant characteristics.
PLoS ONE
PUBLISHED: 01-01-2014
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The HIV-Brazil Cohort Study was established to analyze the effectiveness of combination antiretroviral therapy (cART) and the impact of this treatment on morbidity, quality of life (QOL) and mortality. The study design, patients' profiles and characteristics of cART initiation between 2003 and 2010 were described.
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From pathogen genomes to host plant processes: the power of plant parasitic oomycetes.
Genome Biol.
PUBLISHED: 06-28-2013
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Recent pathogenomic research on plant parasitic oomycete effector function and plant host responses has resulted in major conceptual advances in plant pathology, which has been possible thanks to the availability of genome sequences.
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How to (or not to) ... measure performance against the Abuja target for public health expenditure.
Health Policy Plan
PUBLISHED: 06-03-2013
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In 2001, African heads of state committed to set a target of allocating at least 15% of our annual budget to the improvement of the health sector. This target has since been used as a benchmark to hold governments accountable. However, it was never followed by a set of guidelines as to how it should be measured in practice. This article sets out some of the areas of ambiguity and argues for an interpretation which focuses on actual expenditure, rather than budgets (which are theoretical), and which captures areas of spending that are subject to government discretion. These are largely domestic sources, but include budget support, which is externally derived but subject to Ministry of Finance sectoral allocation. Theoretical and practical arguments in favour of this recommendation are recommended using a case study from Sierra Leone. It is recommended that all discretionary spending by government is included in the numerator and denominator when calculating performance against the target, including spending by all ministries on health, social health insurance payments, debt relief funds and budget support. Conversely, all forms of private payment and earmarked aid should be excluded. The authors argue that the target, while an important vehicle for tracking political commitment to the sector, should be assessed intelligently by governments, which have legitimate wider public finance objectives of maximizing overall social returns, and should be complemented by a wider range of indicators, to avoid distortions.
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Plasma urate in REM sleep behavior disorder.
Mov. Disord.
PUBLISHED: 02-12-2013
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Rapid eye movement (REM) sleep behavior disorder (RBD) is associated with a high risk of developing Parkinsons disease (PD). Higher urate levels are associated with a lower risk of PD. We conducted a study to evaluate plasma urate levels in patients with RBD and their role in the development of PD.
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Facial cues to depressive symptoms and their associated personality attributions.
Psychiatry Res
PUBLISHED: 02-08-2013
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Depression is a common mental health disorder, with 12% of the UK population diagnosed at any one time. We assessed whether there are cues to depressive symptoms within the static, non-expressive face, and if other socially relevant impressions might be made by these cues. Composite "average" face images were created from students scoring high and low on self-report measures of depressive symptoms, capturing potential correlations between facial appearance and symptoms of depression. These were then used in a warping procedure, creating two versions of individual faces, one warped towards the high symptom composite, and the other towards the low. In Experiment 1, we first found observers were able to identify images representing high and low symptom occurrence at levels significantly greater than chance. Secondly, we collected observer impressions of the two versions of each face. The faces reflecting high levels of depressive symptoms were picked as less socially desirable over a broad range of personality trait estimates compared to low symptom images. In Experiment 2, we replicated the key finding that the static face contains cues to levels of depression symptoms, using composites created from a new database of student photos and depression inventory scores.
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Relating localized protein motions to the reaction coordinate in coenzyme B??-dependent enzymes.
FEBS J.
PUBLISHED: 01-20-2013
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The classical picture of enzyme catalysis relies on controlling the entropic and enthalpic contributions by manipulating reaction barriers and co-locating reactants and cofactors to facilitate the reaction chemistry. Catalysis is linked inextricably to the geometry of the enzyme-substrate complex and the chemical/physical properties of the active site, and probably to dynamical contributions that guide reactants along the desired reaction coordinate. Coenzyme B??-dependent enzymes have remarkable catalytic power and unique properties that enable detailed analysis of the reaction chemistry and associated dynamics. Here we discuss recent developments that are beginning to provide atomistic insight into how coenzyme B??-dependent enzymes steer reactants along the reaction coordinate. Such insight will ultimately generate movies of the catalytic process across all relevant time scales. In the longer term, this will enable more predictive engineering of this class of enzyme to achieve new and desirable chemical outcomes.
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Sequential effects in judgements of attractiveness: the influences of face race and sex.
PLoS ONE
PUBLISHED: 01-01-2013
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In perceptual decision-making, a persons response on a given trial is influenced by their response on the immediately preceding trial. This sequential effect was initially demonstrated in psychophysical tasks, but has now been found in more complex, real-world judgements. The similarity of the current and previous stimuli determines the nature of the effect, with more similar items producing assimilation in judgements, while less similarity can cause a contrast effect. Previous research found assimilation in ratings of facial attractiveness, and here, we investigated whether this effect is influenced by the social categories of the faces presented. Over three experiments, participants rated the attractiveness of own- (White) and other-race (Chinese) faces of both sexes that appeared successively. Through blocking trials by race (Experiment 1), sex (Experiment 2), or both dimensions (Experiment 3), we could examine how sequential judgements were altered by the salience of different social categories in face sequences. For sequences that varied in sex alone, own-race faces showed significantly less opposite-sex assimilation (male and female faces perceived as dissimilar), while other-race faces showed equal assimilation for opposite- and same-sex sequences (male and female faces were not differentiated). For sequences that varied in race alone, categorisation by race resulted in no opposite-race assimilation for either sex of face (White and Chinese faces perceived as dissimilar). For sequences that varied in both race and sex, same-category assimilation was significantly greater than opposite-category. Our results suggest that the race of a face represents a superordinate category relative to sex. These findings demonstrate the importance of social categories when considering sequential judgements of faces, and also highlight a novel approach for investigating how multiple social dimensions interact during decision-making.
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Increased expression of multifunctional serine protease, HTRA1, in retinal pigment epithelium induces polypoidal choroidal vasculopathy in mice.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 08-15-2011
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Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the elderly. Wet AMD includes typical choroidal neovascularization (CNV) and polypoidal choroidal vasculopathy (PCV). The etiology and pathogenesis of CNV and PCV are not well understood. Genome-wide association studies have linked a multifunctional serine protease, HTRA1, to AMD. However, the precise role of HTRA1 in AMD remains elusive. By transgenically expressing human HTRA1 in mouse retinal pigment epithelium, we showed that increased HTRA1 induced cardinal features of PCV, including branching networks of choroidal vessels, polypoidal lesions, severe degeneration of the elastic laminae, and tunica media of choroidal vessels. In addition, HTRA1 mice displayed retinal pigment epithelium atrophy and photoreceptor degeneration. Senescent HTRA1 mice developed occult CNV, which likely resulted from the degradation of the elastic lamina of Bruchs membrane and up-regulation of VEGF. Our results indicate that increased HTRA1 is sufficient to cause PCV and is a significant risk factor for CNV.
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[Soil contamination by eggs of soil-transmitted helminths with zoonotic potential in the town of Fernandópolis, State of São Paulo, Brazil, between 2007 and 2008].
Rev. Soc. Bras. Med. Trop.
PUBLISHED: 05-06-2011
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The concentration of dogs and cats in urban areas, associated with an ever-increasing wandering population of these animals, has an important epidemiological role in the soil contamination of public spaces and the spread of infections of several types of parasites. This study aimed to determine the frequency of soil-transmitted helminths with zoonotic potential in public squares and municipal primary schools in Fernandópolis, State of São Paulo, Brazil, conducted between 2007 and 2008.
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Methods used to identify and measure resource use in economic evaluations: a systematic review of questionnaires for older people.
Health Econ
PUBLISHED: 04-26-2011
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This paper presents the findings of a systematic review of full or partial economic evaluations that included questions to service users or their carers to elicit information on the types, amounts or costs of community-based formal social care support provided to people 65 years and older. We have found that studies seldom report use of published validated questions for eliciting information from older people in the UK about their use of formal social care services. Given the political prominence of the debate over funding social care for older people, there remains a need for analysis of policy options. This requires reliable data on the receipt and payment for care. We recommend the development of improved questions on care that are clear, robust and up-to-date with developments in policy and practice.
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Parasitoids select plants more heavily infested with their caterpillar hosts: a new approach to aid interpretation of plant headspace volatiles.
Proc. Biol. Sci.
PUBLISHED: 01-26-2011
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Plants produce volatile organic compounds (VOCs) in response to herbivore attack, and these VOCs can be used by parasitoids of the herbivore as host location cues. We investigated the behavioural responses of the parasitoid Cotesia vestalis to VOCs from a plant-herbivore complex consisting of cabbage plants (Brassica oleracea) and the parasitoids host caterpillar, Plutella xylostella. A Y-tube olfactometer was used to compare the parasitoids responses to VOCs produced as a result of different levels of attack by the caterpillar and equivalent levels of mechanical damage. Headspace VOC production by these plant treatments was examined using gas chromatography-mass spectrometry. Cotesia vestalis were able to exploit quantitative and qualitative differences in volatile emissions, from the plant-herbivore complex, produced as a result of different numbers of herbivores feeding. Cotesia vestalis showed a preference for plants with more herbivores and herbivore damage, but did not distinguish between different levels of mechanical damage. Volatile profiles of plants with different levels of herbivores/herbivore damage could also be separated by canonical discriminant analyses. Analyses revealed a number of compounds whose emission increased significantly with herbivore load, and these VOCs may be particularly good indicators of herbivore number, as the parasitoid processes cues from its external environment.
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Idiopathic anterior knee pain in the young. A prospective controlled trial.
Acta Orthop Belg
PUBLISHED: 08-12-2010
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Idiopathic anterior knee pain is a common condition in adolescents. The aim of this study was to compare the biometric parameters such as hamstring tightness, hip and knee movements and joint laxity in patients with idiopathic anterior knee pain with a control population of similar age and gender. Patients (n = 34) and controls (n = 34) (age and sex matched) between the age of 11 and 25 were recruited for the study. The mean follow-up of the patient group was 20 months. The patients showed a statistically significant improvement in their symptoms (SF-36 physical component, p = 0.001) despite the fact that half of them did not attend physiotherapy sessions. Patients had statistically significant hamstring tightness (p = 0.04) and increased external hip rotation (p = 0.001) as compared to the control group. These findings support the theory of idiopathic anterior knee pain being a self-limiting condition that is associated with hamstring tightness.
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An electromyographic exploratory study comparing the difference in the onset of hamstring and quadriceps contraction in patients with anterior knee pain.
Knee
PUBLISHED: 07-19-2010
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Idiopathic anterior knee pain in teenagers and young adults is a common condition. Patellar maltracking has been considered as a causative factor. The aim of our study was to investigate whether there was a difference in the timing of electromyographic (EMG) activity in the medial and lateral hamstring and quadriceps muscles of patients with anterior knee pain compared to asymptomatic control participants. This was a cross sectional observational study measuring EMG activation patterns. Two groups of participants were tested, one patient (mean age 15 years, n = 20) and one asymptomatic control (mean age 16 years, n = 17). Surface EMG (sampling rate 1000 Hz) was recorded from vastus medialis obliqus, vastus lateralis, and the medial and lateral hamstrings during three repetitions of maximal voluntary isometric contractions. The relative timing of the medial and lateral quadriceps and hamstrings was evaluated. The mean (95% confidence interval) difference between the groups in the lateral-medial hamstring onset timing was 53.8(1.9 to 105.6)ms during the maximal contraction. An independent t test showed that this difference was statistically significant (p = 0.043). The differences between the groups in the relative VMO to VL onset did not reach statistical significance. The results of this study suggest that the lateral hamstrings contract significantly earlier in patients with AKP compared to healthy controls for this small cohort. This altered activation pattern could produce external rotation of the tibia on the femur and cause lateral patella tracking.
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Varying responses of insect herbivores to altered plant chemistry under organic and conventional treatments.
Proc. Biol. Sci.
PUBLISHED: 11-11-2009
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The hypothesis that plants supplied with organic fertilizers are better defended against insect herbivores than those supplied with synthetic fertilizers was tested over two field seasons. Organic and synthetic fertilizer treatments at two nitrogen concentrations were supplied to Brassica plants, and their effects on the abundance of herbivore species and plant chemistry were assessed. The organic treatments also differed in fertilizer type: a green manure was used for the low-nitrogen treatment, while the high-nitrogen treatment contained green and animal manures. Two aphid species showed different responses to fertilizers: the Brassica specialist Brevicoryne brassicae was more abundant on organically fertilized plants, while the generalist Myzus persicae had higher populations on synthetically fertilized plants. The diamondback moth Plutella xylostella (a crucifer specialist) was more abundant on synthetically fertilized plants and preferred to oviposit on these plants. Glucosinolate concentrations were up to three times greater on plants grown in the organic treatments, while foliar nitrogen was maximized on plants under the higher of the synthetic fertilizer treatments. The varying response of herbivore species to these strong differences in plant chemistry demonstrates that hypotheses on defence in organically grown crops have over-simplified the response of phytophagous insects.
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Continuous wave photolysis magnetic field effect investigations with free and protein-bound alkylcobalamins.
J. Am. Chem. Soc.
PUBLISHED: 11-11-2009
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The activation of the Co-C bond in adenosylcobalamin-dependent enzymes generates a singlet-born Co(II)-adenosyl radical pair. Two of the salient questions regarding this process are: (1) What is the origin of the considerable homolysis rate enhancement achieved by this class of enzyme? (2) Are the reaction dynamics of the resultant radical pair sensitive to the application of external magnetic fields? Here, we present continuous wave photolysis magnetic field effect (MFE) data that reveal the ethanolamine ammonia lyase (EAL) active site to be an ideal microreactor in which to observe enhanced magnetic field sensitivity in the adenosylcobalamin radical pair. The observed field dependence is in excellent agreement with that calculated from published hyperfine couplings for the constituent radicals, and the magnitude of the MFE (<18%) is almost identical to that observed in a solvent containing 67% glycerol. Similar augmentation is not observed, however, in the equivalent experiments with EAL-bound methylcobalamin, where all field sensitivity observed in the free cofactor is washed out completely. Parallels are drawn between the latter case and the loss of field sensitivity in the EAL holoenzyme upon substrate binding (Jones et al. J. Am. Chem. Soc. 2007, 129, 15718-15727). Both are attributed to the rapid removal of the alkyl radical immediately after homolysis, such that there is inadequate radical pair recombination for the observation of field effects. Taken together, these results support the notion that rapid radical quenching, through the coupling of homolysis and hydrogen abstraction steps, and subsequent radical pair stabilization make a contribution to the observed rate acceleration of Co-C bond homolysis in adenosylcobalamin-dependent enzymes.
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Time-resolved studies of radical pairs.
Biochem. Soc. Trans.
PUBLISHED: 03-18-2009
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The effect of magnetic fields on chemical reactions through the RP (radical pair) mechanism is well established, but there are few examples, in the literature, of biological reactions that proceed through RP intermediates and show magnetic field-sensitivity. The present and future relevance of magnetic field effects in biological reactions is discussed.
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DNA taxonomy and phylogeography of beetles of the Falkland Islands (Islas Malvinas).
Mol. Phylogenet. Evol.
PUBLISHED: 03-06-2009
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The Falkland biota are generally considered to be derived from the nearest continental source in Patagonian South America, yet they harbor many endemic species whose taxonomy and evolutionary history remains insufficiently understood. Comprehensive sampling of Coleoptera over two field seasons from numerous sites across the Falkland archipelago produced representatives of 55 morphologically separable species, assigned to 35 genera and 13 families of Coleoptera. Partial mitochondrial Cytochrome Oxidase subunit I and 16S ribosomal RNA genes were sequenced for 283 individuals. These sequences formed 55 clusters under a Yule-Coalescent model that largely conformed to Linnean species while deep-level phylogenetic relationships were broadly congruent with the higher level classification. Detailed analysis of the most diverse families Carabidae and Curculionidae addressed the question about the age and persistence in situ of Falkland biota, showing that separation of sister species within genera based on molecular clock estimates pre-dated the Pleistocene in all cases. Intra-specific diversity of mtDNA haplotypes and nucleotide diversity were high in most species, while intra-population variation was equally high and showed local differentiation of populations, but there was no isolation-by-distance relationship. Taken together, these observations indicate that ancient endemics are unlikely to be due to the recent establishment from a source elsewhere, but have persisted in situ. The observed patterns differ greatly from those in climatically similar areas of the Northern Hemisphere. They do not support the view that postglacial ranges of insects near the limits of former glaciations are merely the result of redistribution due to changing climate.
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What Do You Think Would Make You Happier? What Do You Think You Would Choose?().
Am Econ Rev
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Would people choose what they think would maximize their subjective well-being (SWB)? We present survey respondents with hypothetical scenarios and elicit both choice and predicted SWB rankings of two alternatives. While choice and predicted SWB rankings usually coincide in our data, we find systematic reversals. We identify factors-such as predicted sense of purpose, control over ones life, family happiness, and social status-that help explain hypothetical choice controlling for predicted SWB. We explore how our findings vary by SWB measure and by scenario. Our results have implications regarding the use of SWB survey questions as a proxy for utility.
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A lack of sexual dimorphism in width-to-height ratio in white European faces using 2D photographs, 3D scans, and anthropometry.
PLoS ONE
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Facial width-to-height ratio has received a great deal of attention in recent research. Evidence from human skulls suggests that males have a larger relative facial width than females, and that this sexual dimorphism is an honest signal of masculinity, aggression, and related traits. However, evidence that this measure is sexually dimorphic in faces, rather than skulls, is surprisingly weak. We therefore investigated facial width-to-height ratio in three White European samples using three different methods of measurement: 2D photographs, 3D scans, and anthropometry. By measuring the same individuals with multiple methods, we demonstrated high agreement across all measures. However, we found no evidence of sexual dimorphism in the face. In our third study, we also found a link between facial width-to-height ratio and body mass index for both males and females, although this relationship did not account for the lack of dimorphism in our sample. While we showed sufficient power to detect differences between male and female width-to-height ratio, our results failed to support the general hypothesis of sexual dimorphism in the face.
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Ultrafast infrared spectral fingerprints of vitamin B12 and related cobalamins.
J Phys Chem A
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Vitamin B(12) (cyanocobalamin, CNCbl) and its derivatives are structurally complex and functionally diverse biomolecules. The excited state and radical pair reaction dynamics that follow their photoexcitation have been previously studied in detail using UV-visible techniques. Similar time-resolved infrared (TRIR) data are limited, however. Herein we present TRIR difference spectra in the 1300-1700 cm(-1) region between 2 ps and 2 ns for adenosylcobalamin (AdoCbl), methylcobalamin (MeCbl), CNCbl, and hydroxocobalamin (OHCbl). The spectral profiles of all four cobalamins are complex, with broad similarities that suggest the vibrational excited states are related, but with a number of identifiable variations. The majority of the signals from AdoCbl and MeCbl decay with kinetics similar to those reported in the literature from UV-visible studies. However, there are regions of rapid (<10 ps) vibrational relaxation (peak shifts to higher frequencies from 1551, 1442, and 1337 cm(-1)) that are more pronounced in AdoCbl than in MeCbl. The AdoCbl data also exhibit more substantial changes in the amide I region and a number of more gradual peak shifts elsewhere (e.g., from 1549 to 1563 cm(-1)), which are not apparent in the MeCbl data. We attribute these differences to interactions between the bulky adenosyl and the corrin ring after photoexcitation and during radical pair recombination, respectively. Although spectrally similar to the initial excited state, the long-lived metal-to-ligand charge transfer state of MeCbl is clearly resolved in the kinetic analysis. The excited states of CNCbl and OHCbl relax to the ground state within 40 ps with few significant peak shifts, suggesting little or no homolysis of the bond between the Co and the upper axial ligand. Difference spectra from density functional theory calculations (where spectra from simplified cobalamins with an upper axial methyl were subtracted from those without) show qualitative agreement with the experimental data. They imply the excited state intermediates in the TRIR difference spectra resemble the dissociated states vibrationally (the cobalamin with the upper axial ligand missing) relative to the ground state with a methyl in this position. They also indicate that most of the TRIR signals arise from vibrations involving some degree of motion in the corrin ring. Such coupling of motions throughout the ring makes specific peak assignments neither trivial nor always meaningful, suggesting our data should be regarded as IR spectral fingerprints.
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Human cryptochrome-1 confers light independent biological activity in transgenic Drosophila correlated with flavin radical stability.
PLoS ONE
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Cryptochromes are conserved flavoprotein receptors found throughout the biological kingdom with diversified roles in plant development and entrainment of the circadian clock in animals. Light perception is proposed to occur through flavin radical formation that correlates with biological activity in vivo in both plants and Drosophila. By contrast, mammalian (Type II) cryptochromes regulate the circadian clock independently of light, raising the fundamental question of whether mammalian cryptochromes have evolved entirely distinct signaling mechanisms. Here we show by developmental and transcriptome analysis that Homo sapiens cryptochrome--1 (HsCRY1) confers biological activity in transgenic expressing Drosophila in darkness, that can in some cases be further stimulated by light. In contrast to all other cryptochromes, purified recombinant HsCRY1 protein was stably isolated in the anionic radical flavin state, containing only a small proportion of oxidized flavin which could be reduced by illumination. We conclude that animal Type I and Type II cryptochromes may both have signaling mechanisms involving formation of a flavin radical signaling state, and that light independent activity of Type II cryptochromes is a consequence of dark accumulation of this redox form in vivo rather than of a fundamental difference in signaling mechanism.
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Signals of personality and health: the contributions of facial shape, skin texture, and viewing angle.
J Exp Psychol Hum Percept Perform
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To what extent does information in a persons face predict their likely behavior? There is increasing evidence for association between relatively neutral, static facial appearance and personality traits. By using composite images rendered from three dimensional (3D) scans of women scoring high and low on health and personality dimensions, we aimed to examine the separate contributions of facial shape, skin texture and viewing angle to the detection of these traits, while controlling for crucial posture variables. After controlling for such cues, participants were able to identify Agreeableness, Neuroticism, and Physical Health. For personality traits, we found a reliable laterality bias, in that the right side of the face afforded higher accuracy than the left. The separate contributions of shape and texture cues varied with the traits being judged. Our findings are consistent with signaling theories suggesting multiple channels to convey multiple messages.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

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.