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The bacteriophage population is large, dynamic, ancient, and genetically diverse. Limited genomic information shows that phage genomes are mosaic, and the genetic architecture of phage populations remains ill-defined. To understand the population structure of phages infecting a single host strain, we isolated, sequenced, and compared 627 phages of Mycobacterium smegmatis. Their genetic diversity is considerable, and there are 28 distinct genomic types (clusters) with related nucleotide sequences. However, amino acid sequence comparisons show pervasive genomic mosaicism, and quantification of inter-cluster and intra-cluster relatedness reveals a continuum of genetic diversity, albeit with uneven representation of different phages. Furthermore, rarefaction analysis shows that the mycobacteriophage population is not closed, and there is a constant influx of genes from other sources. Phage isolation and analysis was performed by a large consortium of academic institutions, illustrating the substantial benefits of a disseminated, structured program involving large numbers of freshman undergraduates in scientific discovery.

Ocean acidification, chemical changes to the carbonate system of seawater, is emerging as a key environmental challenge accompanying global warming and other human-induced perturbations. Considerable research seeks to define the scope and character of potential outcomes from this phenomenon, but a crucial impediment persists. Ecological theory, despite its power and utility, has been only peripherally applied to the problem. Here we sketch in broad strokes several areas where fundamental principles of ecology have the capacity to generate insight into ocean acidification's consequences. We focus on conceptual models that, when considered in the context of acidification, yield explicit predictions regarding a spectrum of population- and community-level effects, from narrowing of species ranges and shifts in patterns of demographic connectivity, to modified consumer-resource relationships, to ascendance of weedy taxa and loss of species diversity. Although our coverage represents only a small fraction of the breadth of possible insights achievable from the application of theory, our hope is that this initial foray will spur expanded efforts to blend experiments with theoretical approaches. The result promises to be a deeper and more nuanced understanding of ocean acidification'and the ecological changes it portends.

Cryptorchidism, or undescended testes, is the most common disorder of the genitals seen at birth. Due to its high prevalence and short- and long-term sequelae, it is crucial that primary care providers are familiar with the appropriate management of cryptorchidism. This paper serves to review the embryology, diagnosis, management, and treatment of cryptorchidism with the goal of serving as a valuable reference for providers managing pediatric and neonatal urological issues in the primary care setting, using the American Urological Association's most recent guidelines on the subject. Importantly, it also serves as a review of the long-term consequences of cryptorchidism (even after repair) and reinforces the need for continued surveillance for complications throughout a patient's life. [ABSTRACT FROM AUTHOR]

Although the establishment and spread of non-indigenous species depends upon survival in the face of novel environmental conditions and novel biological interactions, relatively little attention has been focused on the specific role of native predators in limiting invasion success. The European common periwinkle, Littorina littorea, was recently introduced to the Pacific coast of Canada and provides a case study of an introduction into an area with an important predator guild (sea stars) that is functionally minor in the invader's native habitat. Here, we assess the likelihood of establishment, spread, and negative ecological impact of this introduced gastropod, with an emphasis on the role of native sea stars as agents of biotic resistance. Size frequency distributions and local market availability suggest that L. littorea was most likely introduced via the live seafood trade. Non-native hitchhikers (e.g., the trematode Cryptocotyle lingua) were found on/in both market and field specimens. Laboratory studies and field observations confirmed that L. littorea can survive seasonal low salinity in Vancouver, British Columbia. Periwinkles also readily consumed native Ulva, suggesting that periwinkles could impact native communities via herbivory or resource competition. Unlike native gastropods, however, L. littorea lacked behavioural avoidance responses to Northeast Pacific predatory sea stars (Pisaster ochraceus and Pycnopodia helianthoides), and sea star predation rates on L. littorea were much higher than predation rates on native turban snails (Chlorostoma funebralis) in common garden experiments. We therefore expect periwinkle establishment in British Columbia to be limited to areas with low predator density, as is seen in its field distribution to date. We caution that this conclusion may understate the importance of the L. littorea introduction if it also serves as a vector for additional non-indigenous species such as C. lingua., Introduction To establish and spread in a novel habitat, a non-indigenous species must survive several filters: conditions during transport, abiotic conditions in the new habitat, and biological interactions with novel [...]

Skin findings in neonates carry a wide differential diagnosis, ranging from self-limiting rashes to something more sinister, as cutaneous changes can be an indicator of a serious underlying infectious process. Even benign rashes can cause great concern for families and providers. Pathologic rashes pose a potential risk to the neonate’s health. Therefore, it is important to diagnose skin findings and provide any necessary treatment swiftly and accurately. This article provides a concise review of neonatal dermatology with the goal to aid providers in diagnosing and managing neonatal skin conditions. [ABSTRACT FROM AUTHOR]

Seaweed and seagrass communities in the northeast Atlantic have been profoundly impacted by humans, and the rate of change is accelerating rapidly due to runaway CO2 emissions and mounting pressures on coastlines associated with human population growth and increased consumption of finite resources. Here, we predict how rapid warming and acidification are likely to affect benthic flora and coastal ecosystems of the northeast Atlantic in this century, based on global evidence from the literature as interpreted by the collective knowledge of the authorship. We predict that warming will kill off kelp forests in the south and that ocean acidification will remove maerl habitat in the north. Seagrasses will proliferate, and associated epiphytes switch from calcified algae to diatoms and filamentous species. Invasive species will thrive in niches liberated by loss of native species and spread via exponential development of artificial marine structures. Combined impacts of seawater warming, ocean acidification, and increased storminess may replace structurally diverse seaweed canopies, with associated calcified and noncalcified flora, with simple habitats dominated by noncalcified, turf-forming seaweeds. [ABSTRACT FROM AUTHOR]

Examines how manifestations of antisocial adolescent behavior affect individuals' future labor market opportunities and decisions. Coverage of relevant literature in occupational choice; Source of data; Estimation techniques and model specification used; Empirical results; Summary and implications of findings; Table of Generalized Method of Moments (GMM) estimates.

Understanding and predicting responses of ectothermic animals to temperature are essential for decision-making and management. The thermal performance curve (TPC), which quantifies the thermal sensitivity of traits such as metabolism, growth and feeding rates in laboratory conditions, is often used to predict responses of wild populations. However, central assumptions of this approach are that TPCs are relatively static between populations and that curves measured under stable temperature conditions can predict performance under variable conditions. We test these assumptions using two latitudinally matched populations of the ecosystem engineer Mytilus trossulus that differ in their experienced temperature variability regime. We acclimated each population in a range of constant or fluctuating temperatures for six weeks and measured a series of both short term (feeding rate, byssal thread production) and long-term (growth, survival) metrics to test the hypothesis that performance in fluctuating temperatures can be predicted from constant temperatures. We find that this was not true for any metric, and that there were important interactions with the population of origin. Our results emphasize that responses to fluctuating conditions are still poorly understood and suggest caution must be taken in the use of TPCs generated under constant temperature conditions for the prediction of wild population responses.

Background: Teach Back is a health communication strategy used to confirm patient understanding in a non-shaming way. Although Teach Back is widely recommended as a best practice strategy for improving patient outcomes and organizational health literacy, there is lack of consensus in the literature on the definition of Teach Back and the best methods for training health care workers (HCWs). Our experience suggests that if you teach specific, observable skills, these can be identified in practice and potentially measured in research., Brief Description of Activity: We created a training program, the 5Ts for Teach Back, based on a standardized operational definition of Teach Back and five specific, observable components. Participants use a Teach-Back Observation Tool to identify the 5Ts in practice and during peer evaluation. The program incorporates lecture, observation, practice, and videos with good and bad examples of Teach Back., Implementation: The training was offered to HCWs in a large academic health care system. Flexible training options ranged from a single 4-hour training to a more comprehensive program that included clinic-specific scenarios, peer coaching, and refresher activities over a 6-month period., Results: The 5Ts for Teach Back operationalizes the definition of Teach Back and provides a model for training HCWs in the use of Teach Back. The 5Ts for Teach Back can be used to train any HCW. A single training session does not guarantee proficiency in practice. Through coaching and refresher activities, competence in Teach Back increases., Lessons Learned: Teaching entire clinical units may increase effectiveness, because Teach Back becomes embedded in the unit culture. The Observation Tool can be used for training, coaching, and evaluation. The standardized method and Observation Tool are potentially useful when evaluating Teach Back during outcomes and patient satisfaction research. [HLRP: Health Literacy Research and Practice. 2020;4(2):94-103.] PLAIN LANGUAGE SUMMARY: Health care workers may be clearer when giving information to patients if they use Teach Back. Studies do not show what methods are best for training health care workers how to do Teach Back. The 5Ts method breaks Teach Back into five skills that help health care workers do it well. The 5Ts can also confirm use and may be helpful for research., (© 2020 Anderson, Leister, De Rego.)