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Fishery biologists are increasingly recognizing the importance of considering the dynamic nature of streams when developing streamflow policies. Such approaches require information on how flow regimes influence the physical environment and how those factors, in turn, affect species-specific demographic rates. A more cost-effective alternative could be the use of dynamic occupancy models to predict how species are likely to respond to changes in flow. To appraise the efficacy of this approach, we evaluated relative support for hypothesized effects of seasonal streamflow components, stream channel characteristics, and fish species traits on local extinction, colonization, and recruitment (meta-demographic rates) of stream fishes. We used 4 years of seasonal fish collection data from 23 streams to fit multistate, multiseason occupancy models for 42 fish species in the lower Flint River Basin, Georgia. Modelling results suggested that meta-demographic rates were influenced by streamflows, particularly short-term (10-day) flows. Flow effects on meta-demographic rates also varied with stream size, channel morphology, and fish species traits. Small-bodied species with generalized life-history characteristics were more resilient to flow variability than large-bodied species with specialized life-history characteristics. Using this approach, we simplified the modelling framework, thereby facilitating the development of dynamic, spatially explicit evaluations of the ecological consequences of water resource development activities over broad geographic areas. [ABSTRACT FROM AUTHOR]

During the past 100 years, most large rivers in North America have been altered for flood control, hydropower, navigation or water supply development. Although these activities clearly provide important human services, their associated environmental disturbances can profoundly affect stream-dwelling organisms. We used dynamic multi-species occupancy models combined with a trait-based approach to estimate the influence of site-level and species-level characteristics on patch dynamic rates for 15 darter species native to the Elk River, a large, flow-regulated Tennessee River tributary in Tennessee and Alabama. Dynamic occupancy modelling results indicated that for every 2.5 °C increase in stream temperature, darters were 3.94 times more likely to colonize previously unoccupied stream reaches. Additionally, large-bodied darter species were 3.72 times more likely to colonize stream reaches compared with small-bodied species, but crevice-spawning darter species were 5.24 times less likely to colonize previously unoccupied stream reaches. In contrast, darters were 2.21 times less likely to become locally extinct for every 2.5 °C increase in stream temperature, but high stream discharge conditions elevated the risk of local extinction. Lastly, the presence of populations in neighbouring upstream study reaches contributed to a lower risk of extinction, whereas the presence of populations in neighbouring downstream study reaches contributed to higher rates of colonization. Our study demonstrates the application of a trait-based approach combined with a metapopulation framework to assess the patch dynamics of darters in a regulated river. Results from our study will provide a baseline for evaluating the ecological consequences of alternative dam operations. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The 'project risk screening matrix' derives from a broader effort to assist US government agency staff in reviewing proposed stream management and restoration projects more efficiently and effectively. The River Restoration Analysis Tool (RiverRAT) developed through this effort provides a thorough, comprehensive and auditable approach to review and evaluate proposed stream actions and projects (). The matrix was initially developed as the first step in applying the RiverRAT, its purpose being to assist reviewers in assessing the risk to natural resources associated with a particular proposal and matching the intensity of their review to the severity of that risk. Hence, the primary application of the matrix to date has been to identify and screen out low risk projects that may be dealt with expeditiously, so freeing the time and technical resources needed to allow deep reviews of higher risk projects. A second form of screening emerged from this primary function because the matrix proved adept at identifying the minimum level of site and project characterization required to support initial risk assessment. On this basis, proposals lacking adequate information can also be screened out, being referred back to the proponent with a request for additional information. More recently, new and novel versions of the matrix, featuring modification and refinement of one or both of the original axes, have emerged to widen and refine its application to linear infrastructure (e.g. pipelines, roads, and electrical transmission lines), in-stream structures (e.g. large wood placement and culvert removal), and pre-application, regulatory, decision-support tools. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

ABSTRACT Efforts to conserve stream and river biota could benefit from tools that allow managers to evaluate landscape-scale changes in species distributions in response to water management decisions. We present a framework and methods for integrating hydrology, geographic context and metapopulation processes to simulate effects of changes in streamflow on fish occupancy dynamics across a landscape of interconnected stream segments. We illustrate this approach using a 482 km2 catchment in the southeastern US supporting 50 or more stream fish species. A spatially distributed, deterministic and physically based hydrologic model is used to simulate daily streamflow for sub-basins composing the catchment. We use geographic data to characterize stream segments with respect to channel size, confinement, position and connectedness within the stream network. Simulated streamflow dynamics are then applied to model fish metapopulation dynamics in stream segments, using hypothesized effects of streamflow magnitude and variability on population processes, conditioned by channel characteristics. The resulting time series simulate spatially explicit, annual changes in species occurrences or assemblage metrics (e.g. species richness) across the catchment as outcomes of management scenarios. Sensitivity analyses using alternative, plausible links between streamflow components and metapopulation processes, or allowing for alternative modes of fish dispersal, demonstrate large effects of ecological uncertainty on model outcomes and highlight needed research and monitoring. Nonetheless, with uncertainties explicitly acknowledged, dynamic, landscape-scale simulations may prove useful for quantitatively comparing river management alternatives with respect to species conservation. Published 2012. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

The activation and subsequent differentiation of naive CD4+ T cells into functionally distinct effector cells is a vital step in the generation of an effective immune response to protein antigens. To analyse the development of effector T cells following the activation of resting, naive CD4+ T cells, we have utilized a transgenic mouse model in which the majority ofT cells express a common T-cell receptor Vβ molecule. The resting T cells were purified and stimulated in vitro with staphylococcal enterotoxin B, in the presence of accessory cells expressing class II major histocompatibility complex (MHC) molecules. We found that the cells which developed from these primary cultures were capable of producing varying levels of interleukin-2 (IL-2), IL-4 and interferon-γ (IFN-γ) following restimulation with anti-Vβ8 antibody, irrespective of whether B cells or macrophages/dendritic cells were the accessory cells in the primary cultures. The addition of [L-4 during primary stimulation enhanced the differentiation of IL-4-producing cells and suppressed the expansion of IFN-γ-producing cells, especially when B cells were the antigen-presenting cells (APC). Neutralization of endogenously produced IL-1, even in the presence of exogenous IL-4, did not inhibit the differentiation of IL-4-producing T cells. Strikingly, IL-10 completely suppressed the development of effector T cells when adherent macrophages/dendritic cells were utilized as accessory cells in the primary cultures, but had minimal effect in the presence of B cells. IFN-γ suppressed the generation of IL-4-producing cells, presumably by inhibiting their expansion following primary activation. Finally, in vitro-generated IL-4-producing T cells were the most potent helpers for B lymphocytes. Thus, exogenous cytokines alter the patterns of T-cell differentiation in vitro, and the effects of cytokines vary depending on the types of accessory cells present during initial T-cell activation. [ABSTRACT FROM AUTHOR]

The nucleotide sequence of the Escherichia coli fep genomic region has been determined. Three new loci were identified. One of these, P43, encodes a membrane protein that is not essential for ferric enterobactin transport. Two others, fepD and fepG, were found to be essential for transport and their translational products showed extensive homology to other integral membrane proteins invoived in TonB-dependent transport processes. The FepC amino acid sequence suggested a peripheral membrane location and revealed conserved ATP-binding domains. Together these data indicate that ferric enterobactin is transported through a typical periplasmic binding protein-dependent system, in addition, the transcriptional organization of these genes was examined and primer extension analysis identified a single iron-regulated bidirectional promoter between the P43 gene and the fepDGC operon. [ABSTRACT FROM AUTHOR]

The purposes of this study were (a) to examine the role of social evaluative concerns in the self-report of sympathy and in the relation of sympathy to helping; and (b) to determine the role of "altruistic personality" traits and situationally induced vicarious emotional responses in the intention to help. Dispositional and situational self-reports of sympathy and other vicarious emotional reactions were obtained for persons who also were given the opportunity to assist a needy other. Moreover, dispositional measures of concern with social evaluation and an altruistic orientation were obtained, and a bogus pipeline manipulation was instituted for half the study participants. Both dispositional and situational self-reported sympathy were positively related to helping, as were other personality indices viewed as reflecting altruistic characteristics. The relations for the dispositional indices of sympathy were not due solely to social evaluative concerns or to other egoistic concerns. The effects on intended helping of dispositional sympathy, perspective taking, and the tendency to ascribe responsibility for others to the self appeared to be both direct and mediated by situational sympathetic responding. Finally, situational sadness did not mediate the effects of sympathetic responsiveness. [ABSTRACT FROM AUTHOR]

Mucinous metaplasia occurs uncommonly in cutaneous pathology, usually at specialized anatomic locations (genitalia, palms, and soles) and within restricted pathologic contexts (inflammation and trauma). Here, we report a unique case of eccrine mucinous metaplasia associated with an apocrine cystadenoma. A 13-year-old girl had an asymptomatic, 4-mm nodule on the chest. Histopathology demonstrated a typical apocrine cystadenoma in the upper and middle dermis. Adjacent to this lesion was a cluster of coiled eccrine secretory glands, of which the inner layer was almost entirely replaced by benign-appearing cells containing abundant, non-sulfated acid mucopolysaccharides. At 10 months' follow up, there was no recurrence. Our case demonstrates that, very uncommonly, mucinous metaplasia may be associated with a pathogenetically separate, adjacent proliferative adenomatous lesion, in this instance, an apocrine cystadenoma.Jiang J, Petronic-Rosic V, Hoag J, Shea CR. Eccrine mucinous metaplasia associated with an apocrine cystadenoma. [ABSTRACT FROM AUTHOR]

Background and Objectives: Physician health programs (PHPs) have demonstrated efficacy, but their mechanism of influence is unclear. This study sought to identify essential components of PHP care management for substance use disorder (SUD), and to assess whether positive outcomes are sustained over time., Methods: Physicians with DSM-IV diagnoses of Substance Dependence and/or Substance Abuse who had successfully completed a PHP monitoring agreement at least 5 years before the study (N = 343) were identified as eligible. Of the 143 (42%) that could be reached by phone, 93% (n = 133; 86% male) completed the anonymous online survey., Results: Virtually all PHP program components were rated as being at least "somewhat helpful" in promoting recovery, with the plurality of respondents rating almost all components as "extremely helpful." The top-rated components were: signing a PHP monitoring agreement, participation in the PHP, formal SUD treatment, and attending 12-step meetings, with each receiving a mean rating of at least 6.2 out of 7. Notably, 88% of respondents endorsed continued participation in 12-step fellowships. Despite the significant financial burden of PHP participation, 85% of respondents reported they believed the total financial cost of PHP participation was "money well spent.", Discussion and Conclusions: Components of PHP monitoring were viewed as acceptable and helpful to physicians who completed the program, and outcomes were generally sustained over 5 years. More studies are needed to confirm these preliminary findings., Scientific Significance: This study documents the perceived cost-benefit of participation in a PHP among a small sample of program completers., (© 2022 The Authors. The American Journal on Addictions published by Wiley Periodicals LLC on behalf of The American Academy of Addiction Psychiatry (AAAP).)

Objectives: Findings from the contemporary psychological and movement science literature that appear to have implications for medical training are reviewed. Specifically, the review focuses on four factors that have been shown to enhance the learning of motor skills: observational practice; the learner's focus of attention; feedback, and self-controlled practice., Observational Practice: Observation of others, particularly when it is combined with physical practice, can make important contributions to learning. This includes dyad practice (i.e. practice in pairs), which is not only cost-effective, but can also enhance learning., Focus of Attention: Studies examining the role of the performer's focus of attention have consistently demonstrated that instructions inducing an external focus (directed at the movement effect) are more effective than those promoting an internal focus (directed at the performer's body movements). An external focus facilitates automaticity in motor control and promotes movement efficiency., Feedback: Feedback not only has an informational function, but also has motivational properties that have an important influence on learning. For example, feedback after successful trials and social-comparative (normative) feedback indicating better than average performance have been shown to have a beneficial effect on learning. SELF-CONTROLLED PRACTICE: Self-controlled practice, including feedback and model demonstrations controlled by the learner, has been found to be more effective than externally controlled practice conditions., Conclusions: All factors reviewed in this article appear to have both informational and motivational influences on learning. The findings seem to reflect general learning principles and are assumed to have relatively broad applicability. Therefore, the consideration of these factors in designing procedures for medical training has the potential to enhance the effectiveness and efficiency of training.

It has been hypothesized that ethanol's actions on the dopamine (DA) system may participate in addiction. The purpose of this study was to evaluate the DA system in the brain of alcoholics. We evaluated 10 alcoholics and 17 nonalcoholics using positron emission tomography and [11C]raclopride to measure DA D2 receptors. In addition, in 5 of the alcoholics and 16 of the nonalcoholics, we also measured DA transporters with [11C]d-threo methylphenidate. The ratio of the distribution volumes in striatum to that in cerebellum, which corresponds to Bmax/Kd + 1, was used as model parameter of DA D2 receptor and transporter availability. Dopamine D2 receptor availability (Bmax/Kd) was significantly lower in alcoholics (2.1 +/- 0.5) than in nonalcoholics (2.7 +/- 0.6) (p < 0.05) and was not correlated with days since last alcohol use. Alcoholics showed DA transporter values similar to those in nonalcoholics. The ratio of DA D2 receptor to transporter availability was significantly higher in nonalcoholics (1.4 +/- 0.1) than in alcoholics (1.1 +/- 0.1) (p < 0.005). Alcoholics showed significant reductions in D2 receptors (postsynaptic marker) but not in DA transporter availability (presynaptic marker) when compared with nonalcoholics. Because D2 receptors in striatum are mainly localized in gamma-aminobutyric acid (GABA) cells these results provide evidence of GABAergic involvement in the dopaminergic abnormalities seen in alcoholics.