304 research outputs found
Intra- and Intergroup Social Anxiety in Different Demographics
From the Washington University Office of Undergraduate Research Digest (WUURD), Vol. 13, 05-01-2018. Published by the Office of Undergraduate Research. Joy Zalis Kiefer, Director of Undergraduate Research and Associate Dean in the College of Arts & Sciences; Lindsey Paunovich, Editor; Helen Human, Programs Manager and Assistant Dean in the College of Arts and Sciences Mentor(s): Thomas L. Rodebaug
EFFECTS OF THE EXTERNAL MUSCLE SYSTEM ON THE FUNCTION OF HAMSTRINGS
The purpose of this study was to develop a device which can simulate the function of the hamstrings and increase these muscles' strength. By wearing it during daily training, one can train the hamstrings according to the specific needs of each sport event. Fifteen subjects were involved in the study and the external muscle system was examined by using EMG and kinetics methods. The results showed that there was an increasing trend in jumping performance and muscle co-contraction (
EFFECTS OF THE EXTERNAL MUSCLE SYSTEM ON THE FUNCTION OF HAMSTRINGS
The purpose of this study is to develop a device which can simulate the function of the hamstrings and increase these muscles' strength. By wearing it during daily training, one can train the hamstrings according to the specific needs of each sport event. Fifteen subjects were involved in the study and the external muscle system was examined by using EMG and kinetics methods. The results showed that there was an increasing trend in jumping performance and muscle co-contraction (pc less than 0.1) during running; There were significant differences (pc less than 0.05): in the first peak force between high loading and none and in the second peak force between low, medium, high loading and none. Thus we believe the system can be used in training sessions. By wearing the system during training, athletes can train muscles when performing movements unique to sport events
Light effects on seedling growth in simulated forest canopy gaps vary across species from different successional stages
Tropical forests continue to suffer from various kinds of disturbances in the
Anthropocene. An immediate impact of disturbances on forest ecosystems is the
creation of numerous large and small canopy gaps, which dramatically affect forest structure and function. Yet, we know little about the effect of canopy gaps on forest successional trajectory. More specifically, the responses of seedlings from different successional stages to increased light intensity under large and small canopy gaps in understory remain unclear. In this study, dominant tree seedlings from early-, mid-, and late-successional stages were selected, respectively from a tropical montane forest in Hainan Island, China to study their growth rate, biomass and traits. Our results showed that the light condition under small canopy gaps (SG, 10–15% of full sunlight) and large canopy gaps (LG, 40–50% of full sunlight) induced greater increment of relative growth rates for seedlings from early- and mid-successional stages relative to that in late-successional stage. Both SG and LG also significantly increased photosynthesis rate, leaf area (LA), light saturation point (LSP), root mass ratio (RMR) and root: shoot ratio, but decreased specific leaf area (SLA) of seedlings across successional stages. Tree seedlings from the earlysuccessional stage displayed the greatest decrease in leaf mass ratio, increase in LA, LSP, and RMR, in comparison to those from mid- and late- successional stages. Light condition and SLA were the most important factors for seedlings’ relative growth rate across successional stages. SLA connected the interaction between the light condition and successional stage on seedlings’ growth, thereby jointly explaining the 93% variation of seedlings’ growth, combining with area-based light saturated rate of CO2 assimilation. Our study highlights the distinct effect of disturbance-induced canopy gaps on seedling regeneration in the understory in tropical forest due to the variation of light intensity. We suspect that the seedlings from late-successional stage will recover relatively slow after disturbances causing canopy losses, which can have detrimental impacts on structure feature an
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Optical biopsy identification and grading of gliomas using label-free visible resonance Raman spectroscopy.
Glioma is one of the most refractory types of brain tumor. Accurate tumor boundary identification and complete resection of the tumor are essential for glioma removal during brain surgery. We present a method based on visible resonance Raman (VRR) spectroscopy to identify glioma margins and grades. A set of diagnostic spectral biomarkers features are presented based on tissue composition changes revealed by VRR. The Raman spectra include molecular vibrational fingerprints of carotenoids, tryptophan, amide I/II/III, proteins, and lipids. These basic in situ spectral biomarkers are used to identify the tissue from the interface between brain cancer and normal tissue and to evaluate glioma grades. The VRR spectra are also analyzed using principal component analysis for dimension reduction and feature detection and support vector machine for classification. The cross-validated sensitivity, specificity, and accuracy are found to be 100%, 96.3%, and 99.6% to distinguish glioma tissues from normal brain tissues, respectively. The area under the receiver operating characteristic curve for the classification is about 1.0. The accuracies to distinguish normal, low grade (grades I and II), and high grade (grades III and IV) gliomas are found to be 96.3%, 53.7%, and 84.1% for the three groups, respectively, along with a total accuracy of 75.1%. A set of criteria for differentiating normal human brain tissues from normal control tissues is proposed and used to identify brain cancer margins, yielding a diagnostic sensitivity of 100% and specificity of 71%. Our study demonstrates the potential of VRR as a label-free optical molecular histopathology method used for in situ boundary line judgment for brain surgery in the margins
Antiviral treatment in outpatients with herps zoster in six major areas of China, 2010–2019
ObjectiveThe objective of this study was to assess the status and trends of antiviral treatment in outpatients with herpes zoster in China.MethodsPrescription data on antiviral drugs were extracted from the database of the Hospital Prescription Analysis Program of China according to the inclusion criteria. Yearly prescriptions and costs were calculated, and trends were analyzed. The trends were further stratified by age, sex, and specific drug use. The distribution of defined daily costs (DDCs) of valaciclovir and famciclovir were analyzed, and trends in the median DDCs were identified.ResultsA total of 132,911 prescriptions from 49 hospitals located in six major areas of China were included in the analysis. The yearly prescriptions containing antivirals increased from 8,819 in 2010 to 16,361 in 2019. The percentage of prescriptions for patients aged 65 years and above also increased (27.7% in 2010 to 31.0% in 2019), and the number of prescriptions for females was higher than those for males (P < 0.001). The average cost of antivirals per prescription decreased; thus, the yearly cost showed no increasing trend. The main prescribed antivirals were valaciclovir and famciclovir, which progressively increased in prescriptions. The use of acyclovir decreased during the study period. Prescriptions containing topical formulations, acyclovir and penciclovir, both increased. The DDCs of valaciclovir and famciclovir decreased dramatically.ConclusionThe use of antivirals has increased over the decade, while the cost has not. Antiviral treatments adhere well to recent recommendations, except for the use of topical antivirals. The findings of this study may benefit the healthcare source allocation and management of herpes zoster in China
Initial therapeutic target attainment of perampanel in pediatric patients with epilepsy
Perampanel is a promising option for the treatment of pediatric epilepsy, but its plasma concentration varies among patients. This retrospective study aimed to investigate the initial target attainment of perampanel plasma concentration in pediatric patients with epilepsy in China. Inpatients admitted from January 2020 to December 2021 in a tertiary hospital were retrospectively included according to pre-set criteria. Demographic characteristics of patients and dosing strategies and therapeutic drug monitoring results were collected. A total of 137 pediatric patients (84 females and 53 males, aged from 0.6 to 16.4 years) were include for analysis. The perampanel concentrations varied greatly from 60 to 1,560 mg/L among patients, but 89.8% had suitable perampanel concentrations (100–1,000 ng/mL). The concomitant use of enzyme-inductive antiepileptic drugs (AEDs) was the only identified risk factor associated with target nonattainment (OR = 5.92, 95% confidence interval 1.68–20.9). Initial perampanel target attainment in pediatric patients is satisfactory. Routine therapeutic drug monitoring to achieved the suggested concentration range for these patients may be unnecessary, except for those receiving combined enzyme inductive AEDs
Landslide hazard assessment based on improved Stacking model
The early warning of landslides is crucial in mitigating the losses caused by frequent and abrupt landslide disasters along the railway. The scientific construction of an evaluation model is pivotal in conducting a comprehensive landslide hazard assessment. Using a railway section in Ya’an City as a case study, an improved Stacking model was developed to assess landslide hazard by selecting eight evaluation factors and employing support vector machines, random forests, K-neighborhood, and naive Bayesian learning. Logical regression was utilized as a meta learning tool to evaluate the model’s performance. To address the issue of a limited number of input samples for the meta learner, the proposed approach incorporates reduced dimensionality data from the original dataset as input for the meta learner. This is based on the output of the base learner, resulting in the establishment of an improved Stacking model. The ROC curve is used to verify the accuracy of the model, compare the accuracy of the Stacking model and the single model before and after the improvement,
and generate the risk zoning map of the study area. The results show that the AUCs of support vector machines, random forests, and stacking models are 0.8068, 0.8203, and 0.8368 , respectively, with good performance, while the accuracy of the improved stacking model reaches 0.8806 . A reference for the prevention and management of geological catastrophes, the accuracy of the landslide hazard zoning map created using ArcGIS in the research area has reached 0.853 , which is essentially compatible with the real distribution
Population pharmacokinetics and individualized dosing of vancomycin for critically ill patients receiving continuous renal replacement therapy: the role of residual diuresis
Background: Vancomycin dosing is difficult in critically ill patients receiving continuous renal replacement therapy (CRRT). Previous population pharmacokinetic (PopPK) models seldom consider the effect of residual diuresis, a significant factor of elimination, and thus have poor external utility. This study aimed to build a PopPK model of vancomycin that incorporates daily urine volume to better describe the elimination of vancomycin in these patients.Methods: We performed a multicenter retrospective study that included critically ill patients who received intermittent intravenous vancomycin and CRRT. The PopPK model was developed using the NONMEM program. Goodness-of-fit plots and bootstrap analysis were employed to evaluate the final model. Monte Carlo simulation was performed to explore the optimal dosage regimen with a target area under the curve of ≥400 mg/L h and 400–600 mg/L h.Results: Overall, 113 observations available from 71 patients were included in the PopPK model. The pharmacokinetics could be well illustrated by a one-compartment model with first-order elimination, with the 24-h urine volume as a significant covariate of clearance. The final typical clearance was 1.05 L/h, and the mean volume of distribution was 69.0 L. For patients with anuria or oliguria, a maintenance dosage regimen of 750 mg q12h is recommended.Conclusion: Vancomycin pharmacokinetics in critically ill patients receiving CRRT were well described by the developed PopPK model, which incorporates 24-h urine volume as a covariate. This study will help to better understand vancomycin elimination and benefit precision dosing in these patients
Macrophages as a Target for Treating Diabetic Foot Ulcers
In all stages of wound healing, macrophages play a pivotal role by coordinating the repair steps in a timely and accurate fashion. The successful completion of wound healing requires proper spatiotemporal presence and function of macrophages. Diabetes significantly alters the proliferation, polarization and functionality of macrophages, leading to a suboptimal but prolonged pro-inflammatory M1-like phenotype in wound macrophages and a failure of their late transition to a reparative M2-like phenotype. This defect in macrophage phenotype and the proper transition results in delayed or even failure of wound healing. Specifically in the diabetic foot ulcer (DFUs), this macrophage dysfunction results in chronic infection and potentially amputation. The abnormal macrophage phenotype in diabetes is not fully understood but is believed to mainly result from epigenetic changes in macrophages and altered interactions between macrophages and other cell types, such as fibroblasts, endothelial cells, neutrophils and T-cells. Recent research on DFUs has focused on developing strategies to improve diabetic wound repair through modulation of macrophage polarization. Treatment of DFUs will greatly benefit from a multi-modal therapy that includes controlling high blood glucose, topical support, prevention of secondary infection, resolution of sustained inflammation and application of cellular therapies targeting macrophages
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