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MD-PhD training programs train physician-scientists to pursue careers involving both clinical care and research, but decreasing numbers of physician-scientists stay engaged in clinical research. We sought to identify current clinical research training methods utilized by MD–PhD programs and to assess how effective they are in promoting self-efficacy for clinical research.
The US MD–PhD students were surveyed in April–May 2018. Students identified the clinical research training methods they participated in, and self-efficacy in clinical research was determined using a modified 12-item Clinical Research Appraisal Inventory.
Responses were received from 61 of 108 MD–PhD institutions. Responses were obtained from 647 MD–PhD students in all years of training. The primary methods of clinical research training included no clinical research training, and various combinations of didactics, mentored clinical research, and a clinical research practicum. Students with didactics plus mentored clinical research had similar self-efficacy as those with didactics plus clinical research practicum. Training activities that differentiated students who did and did not have the clinical research practicum experience and were associated with higher self-efficacy included exposure to Institutional Review Boards and participation in human subject recruitment.
A clinical research practicum was found to be an effective option for MD–PhD students conducting basic science research to gain experience in clinical research skills. Clinical research self-efficacy was correlated with the amount of clinical research training and specific clinical research tasks, which may inform curriculum development for a variety of clinical and translational research training programs, for example, MD–PhD, TL1, and KL2.
Reductions in insulin sensitivity in periparturient dairy cows develop as a means to support lactation; however, excessive mobilization of fatty acids (FA) increases the risk for peripartal metabolic disorders. Our objectives were to investigate the effect of prepartum body condition score (BCS) on systemic glucose and insulin tolerance, and to compare direct and indirect measurements of insulin sensitivity in peripartal lean and overweight dairy cows. Fourteen multiparous Holstein cows were allocated into two groups according to their BCS at day −28 prepartum: lean (n = 7; BCS ≤ 3.0) or overweight; (n = 7; BCS ≥ 4.0). Liver biopsies were performed on day −27, −14 and 4, relative to expected parturition. Intravenous insulin or glucose tolerances tests were performed following each liver biopsy. Relative to lean cows, overweight cows exhibited lower dry matter intake, lost more BCS and displayed increased plasma FA and β-hydroxybutyrate concentrations and elevated liver lipid content during peripartum. Glucose clearance rate was lower for all cows postpartum. Prepartum BCS had minimal effects on insulin and glucose tolerance; however, the ability of the cow to restore blood glucose levels following an insulin challenge was suppressed by increased BCS. Glucose-dependent parameters of insulin and glucose tolerance were not correlated with surrogate indices of insulin sensitivity. We conclude that prepartum BCS had minimal effect on systemic insulin sensitivity following parturition. The observed inconsistency between surrogate indices of insulin sensitivity and direct measurements of insulin and glucose tolerance adds support to growing concerns regarding their usefulness as tools to estimate systemic insulin action in periparturient cows.
Determining infectious cross-transmission events in healthcare settings involves manual surveillance of case clusters by infection control personnel, followed by strain typing of clinical/environmental isolates suspected in said clusters. Recent advances in genomic sequencing and cloud computing now allow for the rapid molecular typing of infecting isolates.
To facilitate rapid recognition of transmission clusters, we aimed to assess infection control surveillance using whole-genome sequencing (WGS) of microbial pathogens to identify cross-transmission events for epidemiologic review.
Clinical isolates of Staphylococcus aureus, Enterococcus faecium, Pseudomonas aeruginosa, and Klebsiella pneumoniae were obtained prospectively at an academic medical center, from September 1, 2016, to September 30, 2017. Isolate genomes were sequenced, followed by single-nucleotide variant analysis; a cloud-computing platform was used for whole-genome sequence analysis and cluster identification.
Most strains of the 4 studied pathogens were unrelated, and 34 potential transmission clusters were present. The characteristics of the potential clusters were complex and likely not identifiable by traditional surveillance alone. Notably, only 1 cluster had been suspected by routine manual surveillance.
Our work supports the assertion that integration of genomic and clinical epidemiologic data can augment infection control surveillance for both the identification of cross-transmission events and the inclusion of missed and exclusion of misidentified outbreaks (ie, false alarms). The integration of clinical data is essential to prioritize suspect clusters for investigation, and for existing infections, a timely review of both the clinical and WGS results can hold promise to reduce HAIs. A richer understanding of cross-transmission events within healthcare settings will require the expansion of current surveillance approaches.
OBJECTIVES/SPECIFIC AIMS: The study aims to determine the current clinical research training interventions of MD-PhD programs and how effective they are in promoting clinical research self-efficacy. METHODS/STUDY POPULATION: A national survey of MD-PhD trainees was conducted in 2018 to identify clinical research training methods and self-efficacy for clinical research skills. MD-PhD program directors and coordinators from 108 institutions were asked to distribute the survey to their students. Responses were received from 61 institutions (56.5%). Responses were obtained from 647 MD-PhD students in all years of training, representing 17.9% of the 3613 possible participants at the 61 medical schools represented. No compensation was provided for this study. RESULTS/ANTICIPATED RESULTS: The primary methods of clinical research training reported by students included didactics, mentored clinical research, didactics plus mentored clinical research, didactics plus clinical research practicum, and didactics plus mentored clinical research plus clinical research practicum. A quarter of all participants reported having no clinical research training. Clinical research self-efficacy was then correlated with the amount of clinical research training. Students exposed to no clinical research had the lowest self-efficacy in clinical research skills and students experiencing didactics plus mentored clinical research plus clinical research practicum had the highest perceived self-efficacy in clinical research domains. DISCUSSION/SIGNIFICANCE OF IMPACT: This is one of the first studies assessing clinical research training methods for MD-PhD students and assessing their efficacy. We found that of all students questioned, 25% mentioned had not received any type of clinical research training. The remaining students identified 5 research training methods that institutions currently use. This work highlights the importance of clinical research experience students need to improve their self-efficacy, a major influence on research career outcomes.
Particle Image Velocimetry (PIV) has been used to study the complex flowfield created by simulated battle damage to a two-dimensional wing. Computational Fluid Dynamics (CFD) predictions have also been used for validation of internal cavity flow. Two damage cases were selected for the study; both cases were simulated using a single hole with diameters equal to 20% and 40% of the chord, located at the wing half-chord. Wind-tunnel tests were conducted at a Reynolds number of 500,000 over a range of incidences from 0 to 10° with two-component PIV measurements made on three chordwise and three spanwise planes. The PIV data were analysed and compared to CFD data of the same damage cases. The PIV data have shown lower velocity ratios and lower vorticity in the jet compared to past Jet in Cross-Flow experiments and CFD was used to describe the flow features inside the cavity of the wing. It was seen that the wing cavity has large effects on the external flow features, particularly for the 20% damage case. Finally, the flow field data have been related to force balance data. At higher incidence angles, the larger force coefficient increments in both lift and drag can be attributed to the larger wakes and higher jet strengths.
The radiocarbon laboratory in the Oceanography Department at Texas A&M University was established primarily for the examination of seawater samples, although other types of samples have been run. Emphasis has been placed on seawater samples of the Gulf of Mexico and adjacent areas. Most of the samples examined have been inorganic carbon, but some organic-carbon samples are being run, mainly wood and charcoal whose ages have been determined previously. More samples of known age will be run as a further check on the reliability of experimental methods and procedures.
We examine two globular cluster formation scenarios with SPH simulations, using GRAPE-3AF. First model is the spontaneous collapse, which is found to induce a disruption of the system. However, the system can survive when sufficiently high external pressure exists. Second model is the collision of the two proto-cluster clouds, which can form a bound stellar system due to efficient cooling and a burst of star formation.
The present study sought to explicate the time-course of posttraumatic stress (PTS)-related attentional bias to threat (ABT) by examining differences in attention bias variability (ABV; a measure which accounts for the temporal dynamics of ABT). A dot-probe task with four presentation durations was used to capture both subliminal and supraliminal stages of processing. Task stimuli consisted of neutral and threat images. Attentional control (AC) was examined as a moderator of the relationship between PTSD and ABV. At an experimental session, participants (PTSD = 11, trauma control = 18) completed questionnaires, a modified dot-probe task, and a stimulus-response task measuring AC. Individuals in the PTSD group exhibited greater ABV compared to trauma control participants. AC moderated this relationship, with participants with PTSD and poor AC exhibiting significantly greater ABV than trauma-exposed control participants with poor AC. These effects remained significant after accounting for traditionally calculated ABT scores and variability on trials for which only neutral stimuli were present, thus ensuring that the observed effects were specific to the presence of threat stimuli and not merely a function of general variability in response times. Findings implicate AC as a buffering mechanism against threat-related attentional dyscontrol among those with PTSD. Clinical implications will be discussed.
Cadmium sulfide (CdS) films were deposited onto glass substrates by chemical bath deposition (CBD) from a bath containing cadmium acetate, ammonium acetate, thiourea, and ammonium hydroxide. The CdS thin films were annealed in argon (neutral atmosphere) or hydrogen (reducing atmosphere) for 1 h at various temperatures (300, 350, 400, 450 and 500 °C). The changes in optical and electrical properties of annealed treated CdS thin films were analyzed. The results showed that, the band-gap and resistivity depend on the post-deposition annealing atmosphere and temperatures. Thus, it was found that these properties of the films, were found to be affected by various processes with opposite effects, some beneficial and others unfavorable. The energy gap and resistivity for different annealing atmospheres was seen to oscillate by thermal annealing. Recrystallization, oxidation, surface passivation, sublimation and materials evaporation were found the main factors of the heat-treatment process responsible for this oscillating behavior. Annealing over 400 °C was seen to degrade the optical and electrical properties of the film.
In this work Al-SiC nanocomposites were prepared by high energy ball milling followed by spark plasma sintering of the powder. For this purpose Al micro-powder was mixed with 50 nm diameter SiC nanoparticles. The final composites had grains of approximately 100 nm dimensions, with SiC particles located mostly at grain boundaries. To characterize their mechanical behavior, uniaxial compression, micro- and nano-indentation were performed. Materials with 1vol% SiC as well as nanocrystalline Al produced by the same means with the composite were processed, tested and compared. AA1050 was also considered for reference. It was concluded that the yield stress of the nanocomposite with 1 vol% SiC is 10 times larger than that of regular pure Al (AA1050). Nanocrystalline Al without SiC and processed by the same method has a yield stress 7 times larger than AA1050. Therefore, the largest increase is due to the formation of nanograins, with the SiC particles’ role being primarily that of stabilizing the grains. This was demonstrated by performing annealing experiments at 150°C and 250°C for 2h, in separate experiments.
To report a rare and unique presentation of metastatic breast cancer.
Case report and review of related literature.
A 62-year-old female with metastatic breast cancer, who had been free from recurrence for 4 years, presented with diplopia secondary to lateral rectus palsy. This was due to a sphenoid sinus metastasis, which was eroding into her cavernous sinus, resulting in VIth cranial nerve neuropathy.
All paranasal sinuses and the orbit are potential sites for metastases. Spread to the paranasal sinuses from breast cancer has been documented previously. However, we believe this to be the only reported case with lateral rectus palsy as a result of metastasis to the sphenoid sinus in which this was the only evidence of disseminated disease. Otolaryngology clinicians need to consider metastatic disease to the sinuses in patients with a history of neoplasia, but also recognise that tamoxifen treatment can itself cause visual disturbance.
A simple method is proposed for the chemical modification of carbon nanotubes (CNT) thin film counter electrodes (CE) for the replacement of fluorine-doped tin oxide (FTO) and platinum catalyst (Pt) while retaining light transparency. In order to decrease the sheet resistance, CNT thin films underwent various concentrations (≤10 M) and durations of HNO3 treatment prior to cell fabrication, and the effect on thin film properties was analyzed. P-doping was observed, and the maximum change in work function was found to be +0.35 eV with 4 M HNO3. Optimum sheet resistance reduction (50%) and work function increment were achieved after 1 h treatment with 4 M HNO3. Changes in optical transmittances for all samples were negligible (± 5%). Pristine and HNO3 treated films on plastic substrates were tested as CE in flexible bifacial dye sensitized solar cells (DSSC). Most significant improvements in conversion efficiencies were obtained when CNT on plastic substrates were pretreated with 8 M HNO3 (from 1.18% to 1.40% under roomlight, from 0.19% to 0.26% under 1 Sun).
This paper describes galvanic corrosion studies of lead, a candidate matrix metal, coupled vith ASTM Grade-2 titanium, a candidate container-shell material, to determine the barrier-lifetime for a lead matrix container - one container concept considered in the Canadian Nuclear Fuel Waste Management Program. In these studies the fractional factorial statistical design of Box-Behnken was used to develop mathematical relationships between the independent variables and the corrosion rate of lead.
Using the mathematical expressions derived in this study, the additional barrier-lifetime that a 25-mm-thick lead layer could provide to a titanium container, which eventually perforates by corrosion, was calculated to be at least 3500 years.
Our efforts to combine the combinatorial technology and microstructure analysis to develop catalysts for proton exchange membrane fuel cell (PEMFC) technology have been described. This offers the realization of “materiomics” in comprehensive material research. Catalyst technologies are indispensable for wide use of PEMFC, which are regarded as the low emission and highly efficient energy conversion device for the next generation. We have applied the combinatorial method for the hydrogen production and/or purification of catalysts, and anode catalyst investigations. The catalyst library consisting of precious metals loaded on various metal oxides was tested for water gas shift reaction and steam reforming of methanol and/or DME. Various metal oxides added to platinum loaded on carbon were screened for anode catalysts. The microstructure of each catalyst was analyzed by employing scanning electron and/or transmission electron microscopy. This paper mainly describes the catalysis screening results of above reactions that form a part of “materiomics”.
In2S3 thin films appear to be a promising candidate for photovoltaic applications due to its stability, wide band gap and photosensitivity. The optical band gap value of Indium sulfide (In2S3) thin films reported in the literature varies from 2.0 eV to 2.4 eV following their synthesis process. These values are too small for an application as buffer layer in solar cells. In Present work, we report that incorporation of Sn using [SnCl4.5H2O] could increase the bandgap to wider ranges. In2S3/Sn thin films were deposited on soda lime glass substrate using chemical spray pyrolysis (CSP) technique. The spraying solution contained indium chloride (InCl3), thiourea [CS(NH2)2] and [SnCl4.5H2O]. Studies were done on films prepared using different Sn/In ratios. Depth profile using x-ray photoelectron spectroscopy showed that incorporation of Sn increased the concentration of oxygen in the samples. Band gap of the films increased with increase in Sn/In ratios. Depending on the ratios, bandgap could be varied from 2.72 eV to 3.78 eV. At lower mixing levels wide band gap low resistive In2S3/Sn films could be obtained which is highly useful for buffer layer applications. Low resistive buffer layer will decrease the series resistance of the cell and wider band gap will improve light transmission in the blue wavelength, both these factors help in increasing the short circuit current of the photovoltaic cell. Samples having higher Sn/In ratios showed wider band gap (up to3.78 eV).Though the samples had very high bandgap and high resistivity these samples were highly photosensitive [(IL-ID)/ID = 11,000]. The results proved that tin incorporation modified the band gap and electrical properties of the In2S3/Sn films favorably over wider ranges making it highly suitable for different optoelectronic applications.
Background: This retrospective chart review evaluated a comparison of the clinical profiles of older outpatients having mania and those with unipolar depression.
Methods: The charts of elderly outpatients with mania and unipolar depression in tertiary care settings were reviewed and relevant information incorporated regarding clinical presentation, past and family history of affective disorder, treatment history and previous psychiatric and neurological history.
Results: Charts for 30 patients with mania (23 men and 7 women with mean (±SD) age of 68.5(± 5.75 years) and 92 with depression (47 men and 45 women with mean (±SD) age of 68.18 (±6.0 years) were evaluated. Fifteen patients (50%) with manic episodes had psychotic symptoms in the form of delusions and hallucinations while only 33 (35.8%) depressed patients had psychotic symptoms. One-third of manic patients received mood stabilizers at index visit. More than half (n = 16; 53.3%) of the patients in the mania group were prescribed antipsychotic medications. On cognitive functions, patients with manic episodes scored poorly compared with those with depression.
Conclusions: These findings suggest that mania in the elderly is a severe form of affective disorder with respect to psychotic and cognitive symptoms. Conclusions from this study are limited due to its retrospective design. Further studies in this area are warranted.