Evidencia de la respuesta a un enterramiento a corto plazo de la fauna macrobentónica asociada a la fanerógama marina del Mediterráneo Cymodocea nodosa

Sedimentation and burial affect a variety of habitats worldwide, especially within coastal marine systems. In the Mediterranean, seagrasses like Cymodocea nodosa are commonly subjected to sedimentation and, although the response of C. nodosa has been documented, few studies have included macrofaunal responses. We used a manipulative field experiment to examine the effects of a single small-scale, pulse burial event on benthic invertebrate macrofauna. Burial did not affect the total abundance, richness, or diversity of higher taxa nor the live abundance or diversity after 5 days. However, live higher taxa richness decreased by day 3. After 5 days, such decrease reversed and partial recovery seemed to occur. Almost 2 months later, three of the buried plots remained with some additional sedimentation, but the other three had lost their sediment. We compared faunal metrics of buried plots between days 5 and 54 and found greater diversity on day 54, providing evidence that macrofaunal recovery apparent 5 days after burial seemed to persist. Although we likely underestimated the effects and can only be conservative with our conclusions, taken together our results suggest small-scale, pulse burial events can have some negative effects on the C. nodosa-associated benthic macrofaunal community, but the community can recover within a few weeks.La sedimentación y el enterramiento afectan a una gran variedad de hábitats en todo el mundo, especialmente en los sistemas costeros marinos. En el Mediterráneo, las fanerógamas marinas como Cymodocea nodosa suelen estar expuestas a la sedimentación y, a pesar de que la respuesta de C. nodosa ha sido documentada previamente, muy pocos estudios hacen referencia a cómo responde la macrofauna. Se ha usado un experimento manipulativo en el campo para examinar los efectos de un enterramiento súbito y puntual a pequeña escala sobre la fauna de invertebrados macrobentónicos. El enterramiento no afectó a la abundancia total, riqueza o diversidad de especies, ni tampoco a la abundancia o diversidad de individuos vivos 5 días después del enterramiento. Sin embargo, la riqueza de taxones vivos disminuyó a partir del día 3. Pasados 5 días, esa disminución revirtió y parece tener lugar una recuperación parcial. Casi 2 meses después, tres de las parcelas enterradas todavía presentaron algún tipo de sedimentación adicional, pero las otras tres habían perdido el sedimento. Se compararon las métricas de la fauna encontrada en los días 5 y 54 en las parcelas enterradas, y se encontró una alta diversidad para el día 54, evidenciando que la aparente recuperación que tuvo lugar 5 días después del enterramiento parece persistir. A pesar de que probablemente hemos subestimado los efectos y debemos ser conservadores con nuestras conclusiones, al examinar los resultados conjuntamente, sugieren que estos eventos repentinos y puntuales de enterramiento a pequeña escala pueden tener efectos negativos sobre la comunidad de fauna macrobentónica asociada a C. nodosa, la cual se recuperaría en unas pocas semanas

Revealing the progenitor of SN 2021zby through analysis of the TESSTESS shock-cooling light curve

We present early observations and analysis of the double-peaked Type IIb supernova (SN IIb) 2021zby. $TESS$ captured the prominent early shock cooling peak of SN 2021zby within the first $\sim$10 days after explosion with a 30-minute cadence. We present optical and near-infrared spectral series of SN 2021zby, including three spectra during the shock cooling phase. Using a multi-band model fit, we find that the inferred properties of its progenitor are consistent with a red supergiant or yellow supergiant, with an envelope mass of $\sim$0.3-3.0 M$_\odot$ and an envelope radius of $\sim$50-350$R_\odot$. These inferred progenitor properties are similar to those of other SNe IIb with double-peak feature, such as SNe 1993J, 2011dh, 2016gkg and 2017jgh. This study further validates the importance of the high cadence and early coverage in resolving the shape of the shock cooling light curve, while the multi-band observations, especially UV, is also necessary to fully constrain the progenitor properties.Comment: 12 pages, 5 figures, 2 tables, submitted to ApJ

Pelvic and breast examination skills curricula in United States medical schools: a survey of obstetrics and gynecology clerkship directors

Background: Learning to perform pelvic and breast examinations produces anxiety for many medical students. Clerkship directors have long sought strategies to help students become comfortable with the sensitive nature of these examinations. Incorporating standardized patients, simulation and gynecologic teaching associates (GTAs) are approaches gaining widespread use. However, there is a paucity of literature guiding optimal approach and timing. Our primary objective was to survey obstetrics and gynecology (Ob/Gyn) clerkship directors regarding timing and methods for teaching and assessment of pelvic and breast examination skills in United States medical school curricula, and to assess clerkship director satisfaction with current educational strategies at their institutions. Methods: Ob/Gyn clerkship directors from all 135 Liaison Committee on Medical Education accredited allopathic United States medical schools were invited to complete an anonymous 15-item web-based questionnaire. Results: The response rate was 70%. Pelvic and breast examinations are most commonly taught during the second and third years of medical school. Pelvic examinations are primarily taught during the Ob/Gyn and Family Medicine (FM) clerkships, while breast examinations are taught during the Ob/Gyn, Surgery and FM clerkships. GTAs teach pelvic and breast examinations at 72 and 65% of schools, respectively. Over 60% of schools use some type of simulation to teach examination skills. Direct observation by Ob/Gyn faculty is used to evaluate pelvic exam skills at 87% of schools and breast exam skills at 80% of schools. Only 40% of Ob/Gyn clerkship directors rated pelvic examination training as excellent, while 18% rated breast examination training as excellent. Conclusions: Pelvic and breast examinations are most commonly taught during the Ob/Gyn clerkship using GTAs, simulation trainers and clinical patients, and are assessed by direct faculty observation during the Ob/Gyn clerkship. While the majority of Ob/Gyn clerkship directors were not highly satisfied with either pelvic or breast examination training programs, they were less likely to describe their breast examination training programs as excellent as compared to pelvic examination training—overall suggesting an opportunity for improvement. The survey results will be useful in identifying future challenges in teaching such skills in a cost-effective manner. Electronic supplementary material The online version of this article (doi:10.1186/s12909-016-0835-6) contains supplementary material, which is available to authorized users

Short-term effects of marijuana smoking on cognitive behavior in experienced male users

The effects of smoking marijuana on the ability to use abstract concepts was tested in 12 experienced marijuana users. Each subject was tested three times, after smoking prepared 300 mg cigarettes containing either 0, 1.5 or 2.9% δ 9 -THC in different sessions according to a Latin Square design. The same number of whole and/or partial cigarettes was smoked by each subject in each of the three sessions. This was determined for individual subjects by the number of 2.9% δ 9 -THC marijuana cigarettes that the subject had been willing to smoke in a pre-experimental session up to a maximum of 1200 mg. The following tests of concept formation and usage were used: 1. a letter series test; 2. a word grouping test; 3. a conceptual clustering memory test; 4. a closure speed test; 5. Witkin's Embedded Figures Test; 6. a size weight illusion test; 7. Luchin's Water Jar Test; 8. Luchin's Hidden Word Test; and 9. an anagram test. Marijuana smoking led to a dose-related impairment on the letter series, word grouping, closure speed, and Embedded Figures test. Performance on the size-weight illusion, Luchin's Water Jar, Luchin's Hidden Word, and the anagram tests were unaffected. Conceptual clustering decreased after marijuana smoking. In most cases only the differences between 0 and 2.9% δ 9 -THC marijuana were statistically significant.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46387/1/213_2004_Article_BF00429295.pd

Training future generations to deliver evidence-based conservation and ecosystem management

1. To be effective, the next generation of conservation practitioners and managers need to be critical thinkers with a deep understanding of how to make evidence-based decisions and of the value of evidence synthesis. 2. If, as educators, we do not make these priorities a core part of what we teach, we are failing to prepare our students to make an effective contribution to conservation practice. 3. To help overcome this problem we have created open access online teaching materials in multiple languages that are stored in Applied Ecology Resources. So far, 117 educators from 23 countries have acknowledged the importance of this and are already teaching or about to teach skills in appraising or using evidence in conservation decision-making. This includes 145 undergraduate, postgraduate or professional development courses. 4. We call for wider teaching of the tools and skills that facilitate evidence-based conservation and also suggest that providing online teaching materials in multiple languages could be beneficial for improving global understanding of other subject areas.Peer reviewe

Dopamine, affordance and active inference.

The role of dopamine in behaviour and decision-making is often cast in terms of reinforcement learning and optimal decision theory. Here, we present an alternative view that frames the physiology of dopamine in terms of Bayes-optimal behaviour. In this account, dopamine controls the precision or salience of (external or internal) cues that engender action. In other words, dopamine balances bottom-up sensory information and top-down prior beliefs when making hierarchical inferences (predictions) about cues that have affordance. In this paper, we focus on the consequences of changing tonic levels of dopamine firing using simulations of cued sequential movements. Crucially, the predictions driving movements are based upon a hierarchical generative model that infers the context in which movements are made. This means that we can confuse agents by changing the context (order) in which cues are presented. These simulations provide a (Bayes-optimal) model of contextual uncertainty and set switching that can be quantified in terms of behavioural and electrophysiological responses. Furthermore, one can simulate dopaminergic lesions (by changing the precision of prediction errors) to produce pathological behaviours that are reminiscent of those seen in neurological disorders such as Parkinson's disease. We use these simulations to demonstrate how a single functional role for dopamine at the synaptic level can manifest in different ways at the behavioural level

Upper limit map of a background of gravitational waves

We searched for an anisotropic background of gravitational waves using data from the LIGO S4 science run and a method that is optimized for point sources. This is appropriate if, for example, the gravitational wave background is dominated by a small number of distinct astrophysical sources. No signal was seen. Upper limit maps were produced assuming two different power laws for the source strain power spectrum. For an f^-3 power law and using the 50 Hz to 1.8 kHz band the upper limits on the source strain power spectrum vary between 1.2e-48 Hz^-1 (100 Hz/f)^3 and 1.2e-47 Hz^-1 (100 Hz /f)^3, depending on the position in the sky. Similarly, in the case of constant strain power spectrum, the upper limits vary between 8.5e-49 Hz^-1 and 6.1e-48 Hz^-1. As a side product a limit on an isotropic background of gravitational waves was also obtained. All limits are at the 90% confidence level. Finally, as an application, we focused on the direction of Sco-X1, the closest low-mass X-ray binary. We compare the upper limit on strain amplitude obtained by this method to expectations based on the X-ray luminosity of Sco-X1.Comment: 11 pages, 9 figures, 2 table

Upper limit map of a background of gravitational waves

We searched for an anisotropic background of gravitational waves using data from the LIGO S4 science run and a method that is optimized for point sources. This is appropriate if, for example, the gravitational wave background is dominated by a small number of distinct astrophysical sources. No signal was seen. Upper limit maps were produced assuming two different power laws for the source strain power spectrum. For an f^-3 power law and using the 50 Hz to 1.8 kHz band the upper limits on the source strain power spectrum vary between 1.2e-48 Hz^-1 (100 Hz/f)^3 and 1.2e-47 Hz^-1 (100 Hz /f)^3, depending on the position in the sky. Similarly, in the case of constant strain power spectrum, the upper limits vary between 8.5e-49 Hz^-1 and 6.1e-48 Hz^-1. As a side product a limit on an isotropic background of gravitational waves was also obtained. All limits are at the 90% confidence level. Finally, as an application, we focused on the direction of Sco-X1, the closest low-mass X-ray binary. We compare the upper limit on strain amplitude obtained by this method to expectations based on the X-ray luminosity of Sco-X1.Comment: 11 pages, 9 figures, 2 table

A review of combined advanced oxidation technologies for the removal of organic pollutants from water

Water pollution through natural and anthropogenic activities has become a global problem causing short-and long-term impact on human and ecosystems. Substantial quantity of individual or mixtures of organic pollutants enter the surface water via point and nonpoint sources and thus affect the quality of freshwater. These pollutants are known to be toxic and difficult to remove by mere biological treatment. To date, most researches on the removal of organic pollutants from wastewater were based on the exploitation of individual treatment process. This single-treatment technology has inherent challenges and shortcomings with respect to efficiency and economics. Thus, application of two advanced treatment technologies characterized with high efficiency with respect to removal of primary and disinfection by-products in wastewater is desirable. This review article focuses on the application of integrated technologies such as electrohydraulic discharge with heterogeneous photocatalysts or sonophotocatalysis to remove target pollutants. The information gathered from more than 100 published articles, mostly laboratories studies, shows that process integration effectively remove and degrade recalcitrant toxic contaminants in wastewater better than single-technology processing. This review recommends an improvement on this technology (integrated electrohydraulic discharge with heterogeneous photocatalysts) viz-a-vis cost reduction in order to make it accessible and available in the rural and semi-urban settlement. Further recommendation includes development of an economic model to establish the cost implications of the combined technology. Proper monitoring, enforcement of the existing environmental regulations, and upgrading of current wastewater treatment plants with additional treatment steps such as photocatalysis and ozonation will greatly assist in the removal of environmental toxicants

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability