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We sought to quantify the possible population-level influence of sediment plumes and algal blooms on yellow perch ( Perca flavescens), a visual predator found in systems with dynamic water clarity. We used an individual-based model (IBM), which allowed us to include variance in water clarity and the distribution of individual sizes. Our IBM was built with laboratory data showing that larval yellow perch feeding rates increased slightly as sediment turbidity level increased, but that both larval and juvenile yellow perch feeding rates decreased as phytoplankton level increased. Our IBM explained a majority of the variance in yellow perch length in data from the western and central basins of Lake Erie and Oneida Lake, with R2 values ranging from 0.611 to 0.742. Starvation mortality was size dependent, as the greatest daily mortality rates in each simulation occurred within days of each other. Our model showed that turbidity-dependent consumption rates and temperature are key components in determining growth and starvation mortality of age-0 yellow perch, linking fish production to land-based processes that influence water clarity. These results suggest the timing and persistence of sediment plumes and algal blooms can drastically alter the growth potential and starvation mortality of a yellow perch cohort. [ABSTRACT FROM AUTHOR]

We used three long-term data sets (gill nets, trawls, and adult population estimates) for walleye (Sander vitreus) to simultaneously estimate density, gear catchabilities, and mortality using an age-structured, nonlinear model. Model constraints included a fixed natural mortality rate and age- and gear-specific but time-invariant catchabilities. Trawl catchability decreased with age, whereas gillnet catchability increased towards a maximum by age-4. A sensitivity analysis was conducted to investigate how the information content of the different data sets influenced parameter estimates. Estimated catchability values were relatively robust to changes in data weighting. Estimated gillnet catchability values were fairly consistent with those derived from more conventional methods. An additional mortality term was added to reflect double-crested cormorant (Phalacrocorax auritus) predation, and vulnerabilities associated with angling and cormorants were calculated using independent length frequency information. Estimated subadult mortality increased and the influence of fishing mortality slightly decreased during recent years when double-crested cormorants were abundant and more restrictive size limits were in place. Walleye density in Oneida Lake (New York, USA) in the last decade is estimated to be approximately half of that before 1990. [ABSTRACT FROM AUTHOR]

In 2006, the Fisheries Management Section of the American Fisheries Society formed the ad hoc Assessment of Fish Aging Techniques Committee to assess the current status of aging freshwater fish in North America. For seven species group that included Black bass (Micropterus spp.), crappie/sunfish ( Pomoxis spp./Lepomis spp.), catfish (Ictaluridae), morinids, percids, salmonids, and esocids, a survey of U .S. and Canadian fisheries agencies (N = 51 agencies responding) revealed that scales, otoliths, and spines were the most common structures used to age fish. Latitudinal clines existed for some of the structures that were examined, with scales typically used more in northern latitudes than otoliths. Many agencies conducted some validation of age estimation techniques and most assessed precision at least for some of the age samples collected. Providing personnel with training to age fish was common. Reasons for the structures used and the types of inferences and information generated from age data were reported. Scales were the most common structure used to age esocids, black bass, crappie/sunfish, and moronids, but only 27% of all respondents felt that males accurately aged fish to the maximum age. Alternatively, most agencies felt that otoliths provided accurate estimates. From a review of published papers, otoliths were more accurate when compared to other aging structures and showed higher precision. Most agencies conducted back-calculation of lengths from annuli that provided additional information on growth, even though back-calculation procedures contain complex and inconsistent interpretation and computation issues. Currently, many studies are being conducted where known-age fish were chemically or physically marked, stocked, then recaptured after a number of years which can furnish data for age validation. Recommendations include the development of a known-age reference database to allow sharing of information, publication of validation studies, and careful consideration for conducting back-calculation of lengths from presumed annuli. [ABSTRACT FROM AUTHOR]

Background: Computer-based diagnostic systems are available commercially, but there has been limited evaluation of their performance. We assessed the diagnostic capabilities of four internal medicine diagnostic systems: Dxplain, Iliad, Meditel, and QMR. Methods: Ten expert clinicians created a set of 105 diagnostically challenging clinical case summaries involving actual patients. Clinical data were entered into each program with the vocabulary provided by the program's developer. Each of the systems produced a ranked list of possible diagnoses for each patient, as did the group of experts. We calculated scores on several performance measures for each computer program. Results: No single computer program scored better than the others on all performance measures. Among all cases and all programs, the proportion of correct diagnoses ranged from 0.52 to 0.71, and the mean proportion of relevant diagnoses ranged from 0.19 to 0.37. On average, less than half the diagnoses on the experts' original list of reasonable diagnoses were suggested by any of the programs. However, each program suggested an average of approximately two additional diagnoses per case that the experts found relevant but had not originally considered. Conclusions: The results provide a profile of the strengths and limitations of these computer programs. The programs should be used by physicians who can identify and use the relevant information and ignore the irrelevant information that can be produced. (N Engl J Med 1994;330:1792-6.) [ABSTRACT FROM AUTHOR]

Gut content analyses have found that round gobies (Neogobius melanostomus) are highly dependent on dreissenid mussels but stable isotope analysis has often suggested that the dreissenid contribution is lower. However, estimation of dietary contributions with stable isotopes relies on accurate discrimination factors (fractionation factors). To test if discrimination values commonly used in aquatic food web studies are suitable for round gobies, we collected round gobies from Oneida Lake, raised them for 63 days under four different diets (Chironomus plumosus, Mytilus chilensis, Dreissenia spp., Euphausia superba) and measured the change in white muscle δ13C and δ15N. Gobies were also collected throughout Oneida Lake for gut content and stable isotope analysis. Diets changed as round gobies grew, with small round gobies (17-42mm) feeding mostly on cladocera and chironomids, intermediate sized gobies (43-94mm) transitioning from chironomid to dreissenid consumption, and larger gobies (95-120mm) predominantly consuming dreissenids, similar to findings in other studies. Discrimination factors were obtained by fitting a commonly used asymptotic regression equation describing changes in fish δ13C and δ15N as a function of time and diet stable isotope ratios. The discrimination factor determined for δ13C (-0.4‰ ± 0.32, SE) was lower than the "standard" value of 0.4‰, while that of δ15N (4.0‰ ± 0.32, SE) was higher than the standard value of 3.4‰. Turnover rates for both δ13C and δ15N were estimated as 0.02 ‰*day-1. The use of experimentally determined discrimination factors rather than "standard" values resulted in model estimates that agree more closely with the observed increasing importance of dreissenids in gut content of larger gobies. Our results suggest that the importance of dreissenid mussels inferred from stable isotope studies may be underestimated when using standard isotopic discrimination values., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Poslednik et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

We analyze the relationship between evolutionary theory and classification of higher taxa in the work of three ichthyologists: Albert C.L.G. Günther (1830-1914), Edward Drinker Cope (1840-1897), and Theodore Gill (1837-1914). The progress of ichthyology in the early years following the Origin has received little attention from historians, and offers an opportunity to further evaluate the extent to which evolutionary theorizing influenced published views on systematic methodology. These three ichthyologists held radically different theoretical views. The apparent commensurability of claims about relationships among groups of fishes belies differences in what the relationships actually were supposed to be. As well, interpreting classification as genealogical did not lead to agreement about taxonomic methodology; instead, applying evolutionary theory raised new axes of disagreement., (© 2023. Springer Nature Switzerland AG.)

Globally, our knowledge on lake fisheries is still limited despite their importance to food security and livelihoods. Here we show that fish catches can respond either positively or negatively to climate and land-use changes, by analyzing time-series data (1970-2014) for 31 lakes across five continents. We find that effects of a climate or land-use driver (e.g., air temperature) on lake environment could be relatively consistent in directions, but consequential changes in a lake-environmental factor (e.g., water temperature) could result in either increases or decreases in fish catch in a given lake. A subsequent correlation analysis indicates that reductions in fish catch was less likely to occur in response to potential climate and land-use changes if a lake is located in a region with greater access to clean water. This finding suggests that adequate investments for water-quality protection and water-use efficiency can provide additional benefits to lake fisheries and food security.

Purpose: To evaluate the Rural Medical Scholars (RMS) Program's effectiveness to produce rural physicians for Alabama., Methods: A nonrandomized intervention study compared RMS (1997-2002) with control groups in usual medical education (1991-2002) at the University of Alabama School of Medicine's main and regional campuses. Participants were RMS and others admitted to regular medical education, and the intervention was the RMS Program. Measures assessed the percentage of graduates practicing in rural areas. Odds ratios compared effectiveness of producing rural Alabama physicians., Findings: The RMS Program (N = 54), regional campuses (N = 182), and main campus (N = 649) produced 48.1% (odds ratio 6.4, P < .001), 23.8% (odds ratio 2.5, P < .001), and 11.2% (odds ratio 1.0) rural physicians, respectively., Conclusions: The RMS Program, contrasted to other local programs of medical education, was effective in producing rural physicians. These results were comparable to benchmark programs in the Northeast and Midwest USA on which the RMS Program was modeled, justifying the assumption that model programs can be replicated in different regions. However, this positive effect was not shared by a disparate rural minority population, suggesting that models for rural medical education must be adjusted to meet the challenge of such communities for physicians., (© 2017 National Rural Health Association.)

Visualizations are nowadays appearing in popular media and are used everyday in the workplace. This democratisation of visualization challenges educators to develop effective learning strategies, in order to train the next generation of creative visualization specialists. There is high demand for skilled individuals who can analyse a problem, consider alternative designs, develop new visualizations, and be creative and innovative. Our three-stage framework, leads the learner through a series of tasks, each designed to develop different skills necessary for coming up with creative, innovative, effective, and purposeful visualizations. For that, we get the learners to create an explanatory visualization of an algorithm of their choice. By making an algorithm choice, and by following an active-learning and project-based strategy, the learners take ownership of a particular visualization challenge. They become enthusiastic to develop good results and learn different creative skills on their learning journey.

Understanding the factors that affect water quality and the ecological services provided by freshwater ecosystems is an urgent global environmental issue. Predicting how water quality will respond to global changes not only requires water quality data, but also information about the ecological context of individual water bodies across broad spatial extents. Because lake water quality is usually sampled in limited geographic regions, often for limited time periods, assessing the environmental controls of water quality requires compilation of many data sets across broad regions and across time into an integrated database. LAGOS-NE accomplishes this goal for lakes in the northeastern-most 17 US states.LAGOS-NE contains data for 51 101 lakes and reservoirs larger than 4 ha in 17 lake-rich US states. The database includes 3 data modules for: lake location and physical characteristics for all lakes; ecological context (i.e., the land use, geologic, climatic, and hydrologic setting of lakes) for all lakes; and in situ measurements of lake water quality for a subset of the lakes from the past 3 decades for approximately 2600-12 000 lakes depending on the variable. The database contains approximately 150 000 measures of total phosphorus, 200 000 measures of chlorophyll, and 900 000 measures of Secchi depth. The water quality data were compiled from 87 lake water quality data sets from federal, state, tribal, and non-profit agencies, university researchers, and citizen scientists. This database is one of the largest and most comprehensive databases of its type because it includes both in situ measurements and ecological context data. Because ecological context can be used to study a variety of other questions about lakes, streams, and wetlands, this database can also be used as the foundation for other studies of freshwaters at broad spatial and ecological scales., (© The Author 2017. Published by Oxford University Press.)

The fatty acid profiles of wild freshwater fish are poorly characterized as a human food source for several classes of fatty acids, particularly for branched chain fatty acids (BCFA), a major bioactive dietary component known to enter the US food supply primarily via dairy and beef fat. We evaluated the fatty acid content of 27 freshwater fish species captured in the northeastern US with emphasis on the BCFA and bioactive polyunsaturated fatty acids (PUFA) most associated with fish, specifically n-3 (omega-3) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Mean BCFA content across all species was 1.0 ± 0.5% (mean ± SD) of total fatty acids in edible muscle, with rainbow smelt (Osmerus mordax) and pumpkinseed (Lepomis gibbosus) the highest at >2% BCFA. In comparison, EPA + DHA constituted 28% ± 7% of total fatty acids. Across all fish species, the major BCFA were iso-15:0, anteiso-15:0, iso-16:0, iso-17:0 and anteiso-17:0. Fish skin had significantly higher BCFA content than muscle tissues, at 1.8% ± 0.7%, but lower EPA and DHA. Total BCFA in fish skins was positively related with that in muscle (r 2 = 0.6). The straight chain saturates n-15:0 and n-17:0 which have been identified previously as markers for dairy consumption were relatively high with means of 0.4% and 0.6%, respectively, and may be an underappreciated marker for seafood intake. Consuming a standardized portion, 70 g (2.5 oz), of wild freshwater fish contributes only small amounts of BCFA, 2.5-24.2 mg, to the American diet, while it adds surprisingly high amounts of EPA + DHA (107 mg to 558 mg).

The University of Alabama School of Medicine (UASOM) instituted a fully integrated, organ system-based preclinical curriculum in 2007. Gross anatomy and embryology were integrated with other basic science disciplines throughout the first two years of undergraduate medical education. Here we describe the methods of instruction and integration of gross anatomy and embryology in this curriculum as well as challenges faced along the way. Gross anatomy and embryology are taught through a combination of didactic lectures, team-based learning activities, and cadaveric dissection laboratories. Vertical integration occurs through third- and fourth-year anatomy and embryology elective courses. Radiology is integrated with anatomy instruction through self-study modules and hands-on ultrasound sessions. Our model of anatomy instruction is time efficient, clinically relevant, and effective as demonstrated by student performance on the United States Medical Licensing Examination(®) (USMLE(®) ) Step 1 examination. We recommend that medical schools considering full integration of gross anatomy and embryology (1) carefully consider the sequencing of organ system modules, (2) be willing to sacrifice anatomical detail for clinical application, (3) provide additional electives to third- and fourth-year students, and (4) integrate radiology with anatomical education., (© 2014 American Association of Anatomists.)

Introduction: medical education to produce rural physicians hinges on the characteristics of students, educational programs, and rural experiences. Family physicians are key components of rural medicine. This study tested the effectiveness of multiple, combined strategies of the Rural Medical Scholars Program to produce family medicine residents., Methods: we compared the relative effectiveness of the Rural Medical Scholars Program, family medicine-oriented branch campuses, and a traditional urban campus to produce family medicine residents using a prospective quasi-experimental design. Logistic regression was used to account for covariates., Results: the relative effectiveness of 3 educational modalities to produce family medicine residents was examined: Rural Medical Scholars Program (44.0%; odds ratio [OR], 15.6), family medicine-oriented branch campuses (18.9%; OR, 5.8), and a traditional urban campus (3.9%; OR, 1). These differences were significant (P < .05) after controlling for sex, race, Medical College Admission Test scores, and graduation rate., Conclusions: the findings are consistent with the literature, which recommends multiple strategy interventions to produce rural physicians (e.g., admit rural students who have an interest in family medicine, use family medicine faculty, and provide rural experiences). Further study will determine whether rural practice follows training in family medicine among Rural Medical Scholars.

Modern pyrosequencing has the potential to uncover many interesting aspects of genome evolution, even in lineages where genomic resources are scarce. In particular, 454 pyrosequencing of nonmodel species has been used to characterize expressed sequence tags, xenobiotics, gene ontologies, and relative levels of gene expression. Herein, we use pyrosequencing to study the evolution of genes expressed in the gonads of a polyploid fish, the lake sturgeon (Acipenser fulvescens). Using 454 pyrosequencing of transcribed genes, we produced more than 125 MB of sequence data from 473,577 high-quality sequencing reads. Sequences that passed stringent quality control thresholds were assembled into 12,791 male contigs and 32,629 female contigs. Average depth of coverage was 4.2 x for the male assembly and 5.5x for the female assembly. Analytical rarefaction indicates that our assemblies include most of the genes expressed in lake sturgeon gonads. Over 86,700 sequencing reads were assigned gene ontologies, many to general housekeeping genes like protein, RNA, and ion binding genes. We searched specifically for sex determining genes and documented significant sex differences in the expression of two genes involved in animal sex determination, DMRT1 and TRA-1. DMRT1 is the master sex determining gene in birds and in medaka (Oryzias latipes) whereas TRA-1 helps direct sexual differentiation in nematodes. We also searched the lake sturgeon assembly for evidence of xenobiotic organisms that may exist as endosymbionts. Our results suggest that exogenous parasites (trematodes) and pathogens (protozoans) apparently have infected lake sturgeon gonads, and the trematodes have horizontally transferred some genes to the lake sturgeon genome.

A pipeline model has been suggested to increase the rural physician supply. This study is an institutional case report used to describe the context, development, and in-house evaluation of the University of Alabama Rural Health Leaders Pipeline, 1990-2005. This program was developed at a University of Alabama School of Medicine branch campus to target rural students at multiple levels, elementary schools through residency, and includes a minority focus. Requirements to enter the medical program include living 8 years in rural Alabama, meeting admission requirements, and affinity for rural lifestyles. Twenty-six percent of 316 high school participants, all 40 students in the minority-focused college program, and 3% of 90 medical program students were African American. The program includes (1) puppet shows in elementary schools depicting different health professions, (2) Rural Health Scholars Program for 11th-grade students, (3) Minority Rural Health Pipeline Program for college students, (4) Rural Medical Scholars Program, a 5-year track of study in rural community health and medicine, and (5) assured admission to family medicine residency. Outcomes studied in this case report included medical school performance, graduation rate, selection of family medicine specialty, and rural practice location. Medical scholars were anticipated to experience academic difficulty, select family medicine specialty, and locate in rural practice more often than peers. Compared to peers, medical scholars showed lower scores on preclinical courses and USMLE steps 1 and 2, reflective of their lower MCAT and GPA scores, but had (1) similar graduation rates (95% vs peers 84%), (2) higher family medicine selection rate (47% vs Huntsville 27% vs Tuscaloosa 12% vs Birmingham 4% [OR compared to Birmingham 22.7, 95% CI 10.5-49.4]), and (3) higher rural practice rate (67% vs peers 14% vs national group 9%) in the first RMSP classes. Based on these important outcomes being better than or equal to the traditional student cohorts, the institution concluded that the Rural Health Leaders Pipeline demonstrates successful use of the rural pipeline model.

Objective: The purpose of this study was to examine the relationship between applicant gender and factors that influence obstetrics and gynecology residency program selection., Study Design: A national survey was conducted of graduates of US allopathic medical schools who were registered with the Electronic Residency Application Service for the year 2003 and who indicated that obstetrics and gynecology was their primary specialty choice. The selection prevalence of 20 possible influential factors was analyzed by gender., Results: Our study cohort consisted of 450 eligible respondents, 80.4% of whom were female. There were no significant differences by gender in regards to applicant age, race, marital status, number of dependents, or geographic region of medical school. Overall, the 4 factors with the highest selection prevalence in both gender groups were all related to workplace environment. Compared with male respondents, female respondents were more likely to consider how well the current residents seemed to work together (99.2% vs 94.3%; P = .002) and the amount of conference/didactic teaching (80.4% vs 68.2%; P = .01). Male respondents were more likely to consider the quality of the hospital facility (92% vs 82%; P = .02), salary (28.4% vs 17.1%; P = .02), and supplemental income (moonlighting) opportunities (18.2% vs 8.6%; P = .008), as compared with female respondents., Conclusion: Significant differences in gender-associated preferences that are related to obstetrics and gynecology residency program selection exist and include both curricular and financial factors.

Objective: Our purpose was to assess the impact of a curriculum designed to improve third-year medical students' knowledge of sexually transmitted diseases, measured by sexually transmitted disease-related items from the National Board of Medical Examiners subject examination and by a locally developed sexually transmitted disease test., Study Design: All students (n = 108) were exposed to a new sexually transmitted disease curriculum: a 2-hour laboratory module, lectures, syllabus, and locally developed pretest/posttest with review of the test prior to taking the National Board of Medical Examiners subject examination. Students were randomized to a attend sexually transmitted disease clinic (n = 47) versus no sexually transmitted disease clinic (n = 61)., Results: Students performed equal to or better than the national average on 85% of the National Board of Medical Examiners sexually transmitted disease-related items after curriculum institution, compared with 56% of the test items prior ( P < .001). Magnitude of improvement was dependent on clerkship timing, with greater improvement in students taking the obstetrics-gynecology clerkship earlier in the third year. Mean postcurriculum test scores of sexually transmitted disease improved significantly ( P < .001), independent of clinic site and clerkship timing., Conclusion: The curriculum for sexually transmitted disease produced significant improvement in third-year medical students' knowledge of sexually transmitted disease. This might have an impact on future prevention and control of sexually transmitted diseases in communities in which these students practice.

Context: Small local colleges may be sources of medical students with the gender, ethnicity, and background that promote identity with and empathy for underserved populations., Purpose: This study examined the impact of attendance at these premedical colleges on outcomes of medical education., Methods: Data for 2508 matriculates to the University of Alabama School of Medicine, a state-supported medical school, were examined according to premedical colleges attended., Findings: Medical students who had graduated from small local colleges were more diverse in gender, race, and rural background than other students. They had slightly lower academic performance in medical school, were more likely to drop out (10.6% versus 5.3% overall), and were more likely to locate in rural areas of the host state., Conclusions: Small local colleges may be rich sources of student diversity and medical students who choose rural practice, outcomes that are gained at a cost in terms of drop-out rate. Compared with other students, minor differences in performance and larger differences in the drop-out rate raise the question of cultural context and social support during medical school as points for intervention.