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OBJECTIVES/SPECIFIC AIMS: 1.Identify barriers to pursuing research for physician trainees 2.Develop a sustainable pipeline of physician-scientists at Duke 3.Coordinate physician-scientist development programs across the School of Medicine under one central Office 4.Provide infrastructure and resources for all physician-scientists 5.Increase the number of MDs and MD/PhDs who pursue, succeed, and are retained in research METHODS/STUDY POPULATION: To establish a baseline understanding of the needs and concerns of physician-scientist trainees at Duke, we conducted focus groups using a standardized interview guide and thematic analysis. Findings from these focus groups were used to develop a framework for support, leading to the creation of the Office of Physician-Scientist Development (OPSD) housed centrally within the Duke School of Medicine. The OPSD integrates programs and resources for multiple populations including medical students, residents, fellows, junior faculty, and faculty mentors. Pipeline programs will also be developed to enhance research engagement in targeted student populations prior to medical school. RESULTS/ANTICIPATED RESULTS: A total of 45 students and faculty participated in the focus groups and structured interviews (1st year medical student, n=11; 4th year medical students, n=11; residents/fellows, n=13; junior faculty, n=11). While participants raised a number of specific issues, one key message emerged: non-PhD MDs in basic research felt they lacked opportunities for directed training. Moreover, they felt the need to teach themselves many critical skills through trial and error. This has led to perceptions that they cannot compete effectively with PhDs and MD-PhD scientists for research funding and positions. Consensus recommendations included: better guidance in choosing mentors, labs, and projects; central resource for information relevant to physician scientists; training specifically tailored to physician scientists conducting laboratory-based research; improved infrastructure and well-defined training pathways; and assistance with grant preparation. To-date, over 90 students, residents, and fellows have been identified who identify as laboratory-based physician scientists. Additional efforts are underway to identify and characterize the broader range of physician-scientist students and trainees at Duke. DISCUSSION/SIGNIFICANCE OF IMPACT: Our planning study revealed specific steps forward toward developing a robust community of physician-scientists at Duke. As a first step, the Dean of the School of Medicine has appointed an Associate Dean of Physician-Scientist Development to oversee a new Office of Physician-Scientist Development (OPSD) being launched in December of 2018. The OPSD will offer four primary programs. 1) A concierge mentoring program will assist new trainees in identifying research areas of interest and mentors. Trainees will receive periodic contact to provide additional support as needed and promote success. 2) A physician-scientist training program is being created to provide training specific to laboratory research skills as well as career and professional development training to complement existing clinical and translational research programs. 3) Integrated training pathways will provide additional mentored research training for those pursuing research careers. Pathways will capitalize on existing resources from R38 programs, while pursuing additional R38 and R25 support. 4) An MD-Scientist funding program has been developed to provide additional research funding and protected time for students pursuing a second research year. Through the support and programming offered by the OPSD, we anticipate decreased perceptions of barriers to pursuing a physician-scientist career and increased satisfaction with training opportunities. Over time, we expect such support to increase the number of MD students pursuing research as a career and the number of residents, fellows, and MD junior faculty remaining in research careers.
Growth mixture modeling with a sample of 749 Mexican heritage families identified parallel trajectories of adolescents’ and their mothers’ heritage cultural values and parallel trajectories of adolescents’ and their fathers’ heritage cultural values from Grades 5 to 10. Parallel trajectory profiles were then used to test cultural gap-distress theory that predicts increased parent–adolescent conflict and adolescent psychopathology over time when adolescents become less aligned with Mexican heritage values compared to their parents. Six similar parallel profiles were identified for the mother–youth and father–youth dyads, but only one of the six was consistent with the hypothesized problem gap pattern in which adolescents’ values were declining over time to become more discrepant from their parents. When compared to families in the other trajectory groups as a whole, mothers in the mother–adolescent problem gap trajectory group reported higher levels of mother–adolescent conflict in the 10th grade that accounted for subsequent increases in internalizing and externalizing symptoms assessed in 12th grade. Although the findings provided some support for cultural gap-distress predictions, they were not replicated with adolescent report of conflict nor with the father–adolescent trajectory group analyses. Exploratory pairwise comparisons between all six mother–adolescent trajectory groups revealed additional differences that qualified and extended these findings.
An assessment of performance of Scottish flocks was made using DAFS census data to impute a lambing percentage. Results showed levels of lambing percentage were generally below potential and threatened viability of hill units.
A postal survey of hill farmers' views on constraints to production was carried out in the Grampian region of Scotland. Farmers were asked for five technical problems in order of importance that they faced and also what management changes, new products or information had affected or would affect their sheep farming. Analysis of 120 replies from farmers owning about 500 000 ewes indicated farmers recognised three major problems. These were tick-borne disease, pneumonia and abortion which accounted for 30% of the problems. Farmers viewed the next most important problems in order of importance as footrot, broken mouth, predators, head fly, barrenness, neonatal deaths, worms, photosensitisation, vaginal prolapse, mastitis, feeding costs, hypothermia, bracken, orf, fluke, pregnancy toxaemia and marketing difficulties. These accounted for a further 40% of problems. Farmers assessed the most important technical advances to be (in order of importance) pregnancy scanning, fluke and worm drenches, pasteurella vaccine, feeding ewes before lambing, feed blocks, clostridial vaccines, land improvement and trace element supplementation. An assessment of technological answers to farmers' problems indicated that, although some technical problems remained unsolved, many practical solutions had been demonstrated but not yet fully taken up by farmers.
Investigations of culling and particularly involuntary culling (“functional” longevity) have often used different criteria on herds of varying size in different regions and with divergent average milk outputs (Young, Waddington, Sales, Bradley and Spooner, 1983; Esslemont and Kossaibati, 1997; Forbes, Gayton and McGeogh, 1999; Whitaker Kelly and Smith, 2000; Figure 1). Thus the evidence of increasing or decreasing culling for any particular entity is uncertain.
Escherichia coli O157 are zoonotic bacteria for which cattle are an important reservoir. Prevalence estimates for E. coli O157 in British cattle for human consumption are over 10 years old. A new baseline is needed to inform current human health risk. The British E. coli O157 in Cattle Study (BECS) ran between September 2014 and November 2015 on 270 farms across Scotland and England & Wales. This is the first study to be conducted contemporaneously across Great Britain, thus enabling comparison between Scotland and England & Wales. Herd-level prevalence estimates for E. coli O157 did not differ significantly for Scotland (0·236, 95% CI 0·166–0·325) and England & Wales (0·213, 95% CI 0·156–0·283) (P = 0·65). The majority of isolates were verocytotoxin positive. A higher proportion of samples from Scotland were in the super-shedder category, though there was no difference between the surveys in the likelihood of a positive farm having at least one super-shedder sample. E. coli O157 continues to be common in British beef cattle, reaffirming public health policy that contact with cattle and their environments is a potential infection source.
Unusual speleothems, associated with hyperalkaline (pH > 12) groundwaters
have formed within a shallow, abandoned railway tunnel at Peak Dale,
Derbyshire, UK. The hyperalkaline groundwaters are produced by the leaching
of a thin layer (<2 m) of old lime-kiln waste on the soil-bedrock surface
above the tunnel by rainwater. This results in a different reaction and
chemical process to that more commonly associated with the formation of
calcium carbonate speleothems from Ca-HCO3-type groundwaters and
degassing of CO2. Stalagmites within the Peak Daletunnel have
grown rapidly (averaging 33 mm y–1), following the closure of the
tunnel 70 years ago. They have an unusual morphology comprising a central
sub-horizontally-laminated column of micro- to nano-crystalline calcium
carbonate encompassed by an outer sub-vertical assymetricripple-laminated
layer. The stalagmites are composed largely of secondary calcite forming
pseudomorphs (<1 mm) that we believe to be predominantly after the 'cold
climate' calcium carbonate polymorph, ikaite (calcium carbonate hexahydrate:
CaCO3·6H2O), withminor volumes of small (<5 μm)
pseudomorphs after vaterite. The tunnel has a near constant temperature of
8–9°C, which is slightly above the previously published crystallization
temperatures for ikaite (<6°C). Analysis of a stalagmite actively growing
at the time ofsampling, and preserved immediately within a dry nitrogen
cryogenic vessel, indicates that following crystallization of ikaite,
decomposition to calcite occurs rapidly, if not instantaneously. We believe
this is the first occurrence of this calcium carbonate polymorph observed
Sorted patterned ground refers to polygons, nets, or stripes defined by rocky borders which are the result of sorting in soil subjected to frost action. This paper presents a model in which convection cells, driven by unstable density stratification in the aqueous phase, result in uneven melting of the underlying ice front during thawing. The resulting undulatory ice front with regularly spaced peaks and troughs provides the pattern which results in the regularity observed for certain types of patterned ground. In addition, the model predicts the width to depth-of-sorting ratio for both polygons and stripes, and explains the characteristic hexagonal shape of sorted polygons, the transition from sorted polygons to sorted stripes on sloped terrain, and the formation of sorted polygons under water. The predicted ratio of width to depth-of-sorting of 3.81 for sorted polygons is compared with the ratio of width to depth-of-sorting of 3.57 found from a linear regression analysis of 18 field study data.
In the dairy industry, excess dietary CP is consistently correlated with decreased conception rates. However, amount of excess CP effects on reproductive function in beef cattle is largely undefined. The objective of this experiment was to determine the effects of excess metabolizable protein (MP) supplementation from a moderately abundant rumen undegradable protein (RUP) source (corn gluten meal: 62% RUP) on ovarian function and circulating amino acid (AA) concentrations in beef cows consuming low quality forage. Non-pregnant, non-lactating beef cows (n=16) were allocated by age, BW and body condition score (BCS) to 1 of 2 isocaloric supplements designed to maintain BW for 60 days. Cows had ad libitum access to corn stalks and were individually offered a corn gluten meal-based supplement daily at 125% (MP125) or 150% (MP150) of National Research Council (NRC) MP requirements. After a 20-day supplement adaptation period, cows were synchronized for ovulation. After 10 days of synchronization, follicular growth was reset with gonadotropin releasing hormone. Daily thereafter, transrectal ultrasonography was performed to diagram ovarian follicular waves, and blood samples were collected for hormone, metabolite and AA analyses. After 7 days of observation of estrus, corpus luteum (CL) size was determined via ultrasound. Data were analyzed using the MIXED procedures of SAS. No differences (P⩾0.21) in BW and BCS existed throughout the study; however, plasma urea N at ovulation was greater (P=0.04) in MP150. Preovulatory ovarian follicle size at dominance, duration of dominance, size at spontaneous luteolysis, length of proestrus and wavelength were not different (P⩾0.11) between treatments. However, ovulatory follicles were larger (P=0.04) and average antral follicle count was greater (P=0.01) in MP150 than MP125. Estradiol concentration and ratio of estradiol to ovulatory follicle volume were not different due to treatment (P⩾0.25). While CL volume 7 days post-estrus was greater (P<0.01) in MP150 than MP125, circulating progesterone 7 days post-estrus and ratio of progesterone to CL volume were not different (P⩾0.21). Total AA were not different (P⩾0.76) at study initiation or completion; however, as a percent of total AA, branched-chain AA at ovulation were greater (P=0.02) in MP150. In conclusion, supplementation of CP at 150% of NRC MP requirements from a moderately undegradable protein source may enhance growth of the ovulatory follicle and subsequent CL compared with MP supplementation at 125% of NRC MP requirements.
In the dairy industry, excess dietary CP is consistently correlated with decreased conception rates. However, the source from which excess CP is derived and how it affects reproductive function in beef cattle is largely undefined. The objective of this experiment was to determine the effects of feeding excess metabolizable protein (MP) from feedstuffs differing in rumen degradability on ovulatory follicular dynamics, subsequent corpus luteum (CL) development, steroid hormone production and circulating amino acids (AA) in beef cows. Non-pregnant, non-lactating mature beef cows (n=18) were assigned to 1 of 2 isonitrogenous diets (150% of MP requirements) designed to maintain similar BW and body condition score (BCS) between treatments. Diets consisted of ad libitum corn stalks supplemented with corn gluten meal (moderate rumen undegradable protein (RUP); CGM) or soybean meal (low RUP; SBM). After a 20-day supplement adaptation period, cows were synchronized for ovulation. After 10 days of synchronization, gonadotropin releasing hormone (GnRH) was administered to reset ovarian follicular growth. Starting at GnRH administration and daily thereafter until spontaneous ovulation, transrectal ultrasonography was used to diagram ovarian follicular growth, and blood samples were collected for hormone, metabolite and AA analyses. After 7 days of visual detection of estrus, CL size was determined via ultrasound. Data were analyzed using the MIXED procedures of SAS. As designed, cow BW and BCS were not different (P⩾0.33). Ovulatory follicular wavelength, antral follicle count, ovulatory follicle size at dominance and duration of dominance were not different (P>0.13) between treatments. Cows supplemented with CGM had greater post-dominance ovulatory follicle growth, larger dominant follicles at spontaneous luteolysis, shorter proestrus, and larger ovulatory follicles (P⩽0.03) than SBM cows. No differences (P⩾0.44) in peak estradiol, ratio of estradiol to ovulatory follicle volume, or plasma urea nitrogen were observed. While CL volume and the ratio of progesterone to CL volume were not affected by treatment (P⩾0.24), CGM treated cows tended to have decreased (P=0.07) circulating progesterone 7 days post-estrus compared with SBM cows. Although total circulating plasma AA concentration did not differ (P=0.70) between treatments, CGM cows had greater phenylalanine (P=0.03) and tended to have greater leucine concentrations (P=0.07) than SBM cows. In summary, these data illustrate that excess MP when supplemented to cows consuming a low quality forage may differentially impact ovarian function depending on ruminal degradability of the protein source.
Gravitational lens surveys are of cosmological interest because they provide a way to measure the gravitational field of both luminous and dark matter. Many of the other methods used to detect the presence of dark matter, such as studies of galaxy rotation curves and cluster dynamics, require that there be luminous objects in the gravitational field that act as tracers of the mass. This may introduce a selection effect. In constrast, in studies of gravitational lenses, the beacon we observe can be far (at distances of order one thousand Mpc) from the gravitational field. In this paper we describe a VLA survey designed to detect gravitational lensing on sub-arc second and arc second scales. We also present a preliminary result of the radio data: we find that the density of matter in the form of a uniform, comoving number density of 1011 to 1012M⊙ compact objects, luminous or dark, must be substantially less than the critical density.
The preparation of a report dealing with such a large domain is almost an impossible task. Because so many different questions, problems and expertises are assembled under the word “Cosmology”, my approach has been the following: first to divide this field in a somewhat arbitrary fashion into the following sections: very early universe – elementary particle and cosmology – early nucleosynthesiscosmological parameters (Hubble constant, deceleration parameter, cosmological constant) – large scale structures, intergalactic gas, missing mass – clusters of galaxies and intercluster gas – anisotropy of the black body radiation – formation of galaxies – quasars and their evolution – cosmological evolution of radiosources. I have then asked to the most knowledgeable specialists to review briefly each of these most important questions on which many excitinq and very new results have been obtained not only by the astrophysicists themselves but also by particle physicists, nuclear physicists, theoretical physicists, … This is why the reader will read in section 1 the report on primordial nucleosynthesis written by G. Steigman, in section 2 Anisotropy of the black body radiation by D.T. Wilkinson and E. Meichiorri, in section 3 Clusters of galaxies by 3. Einasto, in section 4 Galaxy formation by B.J.T. Jones, in section 5 Quasars and their evolution by M. Schmidt and in section 6 the Cosmological evolution of radio sources by R.A. Windhorst. Let me thank these colleagues for their excellent work in writing these various reviews.