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Approximatively 25 chemical elements are essential for the maintenance, growth and reproduction of all living organisms. Hence, the movement, distribution, and relative proportions of those elements on the landscape should have significant influence on the structure and functioning of biological communities. Yet our basic understanding for the spatial distribution of elements across landscapes and the drivers of those patterns are limited. Here, we propose a novel framework to apply tools from community and landscape ecology to study spatial patterns in elements. We illustrate this framework with an empirical proof of concept in the boreal forest and demonstrate how spatial grain and spatial dissimilarity of elements interact leading to predictable patterns in elemental distributions at various spatial scales. In particular, we observe that at finer spatial grains, sites with high contributions to elemental dissimilarity cluster together. As grain size increases, the landscape becomes more homogeneous with larger patches of sites with intermediate contributions to elemental dissimilarity emerging near aquatic-terrestrial boundaries. Meanwhile, an analysis revealed that the most important elemental contributors to spatial dissimilarity in this landscape are potassium and calcium, two infrequently studied elements in community ecology, raising new questions about their role in, or response to, distributions of biodiversity and ecosystem functions. Our novel framework demonstrates how we can use community metrics (e.g., dissimilarity) to investigate variability of individual elements, the building blocks of stoichiometric ratios, across landscapes. As a field, ecology is just beginning to fully acknowledge the contribution of biotic factors in shaping biogeochemical processes, but here we provide a framework for integrating abiotic and biotic processes. We conclude by hypothesizing that changes in the evenness or beta-diversity of elements should reflect the structure of biotic communities, providing a long-sought mechanistic link between community and ecosystem processes that can be measured directly in the field.

The integration of ecosystem processes over large spatial extents is critical to predicting whether and how global changes may impact biodiversity and ecosystem functions. Yet, there remains an important gap in meta-ecosystem models to predict multiple functions (e.g., carbon sequestration, elemental cycling, trophic efficiency) across ecosystem types (e.g., terrestrial-aquatic, benthic-pelagic). We derive a flexible meta-ecosystem model to predict ecosystem functions at landscape extents by integrating the spatial dimension of natural systems as spatial networks of different habitat types connected by cross-ecosystem flows of materials and organisms. We partition the physical connectedness of ecosystems from the spatial flow rates of materials and organisms, allowing the representation of all types of connectivity across ecosystem boundaries as well as the interaction(s) between them. Through simulating a forest-lake-stream meta-ecosystem, our model illustrated that even if spatial flows induced significant local losses of nutrients, differences in local ecosystem efficiencies could lead to increased secondary production at regional scale. This emergent result, which we dub the ‘cross-ecosystem efficiency hypothesis’, emphasizes the importance of integrating ecosystem diversity and complementarity in meta-ecosystem models to generate empirically testable hypotheses for ecosystem functions.

Abstract Rationale Adolescents represent a vulnerable group due to increased experimentation with illicit substances that is often associated with the adolescent period, and because adolescent drug use can result in long-term effects that differ from those caused by drug use initiated during adulthood. Objectives The purpose of the present study was to determine the effects of repeated heroin vapor inhalation during adolescence on measures of nociception, and anxiety-like behavior during adulthood in female and male Wistar rats. Methods Rats were exposed twice daily to 30 min of heroin vapor from post-natal day (PND) 36 to PND 45. At 12 weeks of age, baseline thermal nociception was assessed across a range of temperatures with a warm-water tail-withdrawal assay. Anxiety-like behavior was assessed in an elevated plus-maze (EPM) and activity was measured in an open-field arena. Starting at 23 weeks of age, baseline thermal nociception was re-assessed, nociception was determined after acute heroin or naloxone injection, and anxiety-like behavior was redetermined in the EPM. Results Adolescent heroin inhalation altered baseline thermal nociception in female rats at 12 weeks of age and in both female and male rats at ~ 23 weeks. Heroin-treated animals exhibited anxiety-like behavior when tested in the elevated plus-maze, showed blunted heroin-induced analgesia, but exhibited no effect on naloxone-induced hyperalgesia. Conclusions The present study demonstrates that heroin vapor inhalation during adolescence produces behavioral and physiological consequences in rats that persist well into adulthood.

Patients with lower educational attainment are underrepresented in inflammatory bowel disease (IBD) research. To increase our understanding of the health care perspectives of patients with less than a university degree, semi-structured interviews were conducted among 23 outpatients at the McGill University Health Centre IBD Centre (Montreal, Canada). Thematic analysis was used to analyze the qualitative data. Perspectives focused on communication with health care professionals, access to care, symptoms and treatment, and outside support. Access to an IBD specialist was the most important aspect of care. Good care, kind and receptive staff, and a lengthy delay to diagnosis were frequently reported experiences. IBD specialists, nurses, and family and friends were most helpful in managing disease. Physical and emotional symptoms, reduced social engagement, and medications were difficult aspects of living with IBD. An ideal IBD clinic would provide access to traditional and non-traditional services and assist with obtaining support to help patients engage in social activities, increase affordability of care, and maintain employment. Study findings may be helpful in designing equitable models of health care delivery.

Background With the current trend to reduce postoperative opioid use to enhance recovery and address perioperative opioid addiction concerns, the challenge of managing pain after total knee arthroplasty has increased. This study examined the effect of adding a preoperative medication regime to a multimodal postoperative analgesia protocol that included regional anaesthesia. Materials and methods Sixty patients undergoing elective first-time unilateral knee arthroplasty received celecoxib 100mg, gabapentin 600mg and dexamethasone 10mg po one hour before skin incision. They were compared to a sequential retrospective cohort of 49 patients. All patients routinely received acetaminophen 650mg po q6h, ibuprofen 400mg po q8h, patient-controlled opioid analgesia and continuous adductor canal blocks postoperatively. Pain scores and opioid consumption were recorded at 4, 8, 12, 24 and 48h. Results Pain scores and cumulative opioid use were statistically and clinically significantly reduced at all time points up to 48h. Conclusions Combining preoperative oral celecoxib, gabapentin and dexamethasone had a clinically significantly effect in reducing pain scores and opioid use for at least 48h. Most of this effect is probably due to dexamethasone.

Distinctions are usually drawn between social entrepreneurship and corporate social responsibility based upon the implications, the impact, and the stimulus required. Limited empirical evidences ar...

Purpose To examine the ability of surgeons to identify the osseous landmarks associated with the femoral anterior cruciate ligament (ACL) footprint and locate optimal tunnel placement on 3-dimensional (3D) printed models compared with intraoperative placement. Methods Twelve sports fellowship-trained orthopaedic surgeons were asked to identify a femoral landmark and an ACL footprint on 10 different 3D printed knees. The 3D models were made based on 20 real patients with different anatomical morphology who later received ACL reconstructive surgery using independent drilling. ImageJ software was used to quantify the measurements, which were then analyzed using descriptive statistics. Results Overall, none of the surgeons were able to consistently identify the junction of the bony ridges. The mean error per participant ranged from 2.81 to 7.34 mm in the proximal direction (P = 3.30e-05) and from 2.42 to 8.05 mm in the posterior direction (P =4.88e-12). None of the surgeons were able to appropriately identify the center of the femoral footprint on the anatomic 3D models. The difference between the center of the footprint surgeons identified on the 3D model and the tunnel graft location in surgery was significantly different (P = .0046). On average, the magnitude of the error when the surgeons performed the actual surgery was 3.72 ± 2.43 mm, whereas on the 3D models it was 5.82 ± 1.97 mm. Conclusions Experienced sports fellowship-trained orthopaedic surgeons were unable to correctly identify the junction of the intercondylar and bifurcate ridges and the native ACL footprint on 3D models. Operatively placed tunnels were more accurate implying that looking either through a scope or soft-tissue landmarks play a significant role in surgeons ACL footprint localization. Clinical Relevance The graft position for ACL reconstruction plays an important role on the kinematics of the knee. This paper shows that soft tissue landmarks are needed to provide reliable reference points for reconstruction.

The transition from recreational drug use to addiction involves pathological learning processes that support a persistent shift from flexible, goal‐directed to habit behavioral control. Here, we examined the molecular mechanisms supporting altered function in hippocampal (HPC) and dorsolateral striatum (DLS) memory systems following abstinence from repeated cocaine. After 3 weeks of cocaine abstinence (experimenter‐ or self‐administered), we tested new behavioral learning in male rats using a dual‐solution maze task, which provides an unbiased approach to assess HPC‐ versus DLS‐dependent learning strategies. Dorsal hippocampus (dHPC) and DLS brain tissues were collected after memory testing to identify transcriptional adaptations associated with cocaine‐induced shifts in behavioral learning. Our results demonstrate that following prolonged cocaine abstinence rats show a bias toward the use of an inflexible, habit memory system (DLS) in lieu of a more flexible, easily updated memory system involving the HPC. This memory system bias was associated with upregulation and downregulation of brain‐derived neurotrophic factor (BDNF) gene expression and transcriptionally permissive histone acetylation (acetylated histone H3, AcH3) in the DLS and dHPC, respectively. Using viral‐mediated gene transfer, we overexpressed BDNF in the dHPC during cocaine abstinence and new maze learning. This manipulation restored HPC‐dependent behavioral control. These findings provide a system‐level understanding of altered plasticity and behavioral learning following cocaine abstinence and inform mechanisms mediating the organization of learning and memory more broadly.

Advances in drug vapor exposure systems have enabled evaluation of Δ-9-tetrahydrocannabinol (THC) vapor effects in laboratory animals. The purpose of this study was to 1) establish a range of parameters of THC vapor exposure in rats sufficient to produce a behavioral dose-effect curve in a battery of tasks sensitive to THC; and 2) to investigate sex differences in the effects of THC vapor exposure and THC injection (intraperitoneal, IP) on these behaviors in two strains of outbred rats. Male and female Sprague Dawley and Wistar rats (N=22, 5-6/sex per group) received THC via passive vapor exposure (200mg/mL; 5 conditions) and IP injection (1-20mg/kg) in a within subject design. The effects of vaped and injected THC on appetite was determined using progressive ratio responding for food pellets. THC effects on nociception, measured using the tail withdrawal assay, and body temperature were also assessed during a 5-h test period for evaluation of time course of effects. Plasma THC concentrations were assessed after THC vapor and 10mg/kg IP THC. THC vapor produced exposure-related increases and decreases in motivation to obtain food under the progressive ratio schedule. IP THC (3-20mg/kg) reduced breakpoints. Vaped and injected THC produced exposure and dose-dependent antinociception and hypothermia. Sex and strain differences in THC effects were also observed. Plasma THC concentrations were higher after 10mg/kg IP THC (152ng/mL) compared to the highest vapor exposure condition tested (38ng/mL), but magnitude of behavioral effects were comparable. THC vapor exposure produced reliable, dose orderly effects on food-maintained behavior, nociception, and body temperature that are comparable to effects of IP THC, although there were differences in the time course of behavioral outcomes.

External beam radiotherapy often includes the use of field sizes 3 × 3 cm2 or less, which can be defined as small fields. Dosimetry is a difficult, yet important part of the radiotherapy process. The dosimetry of small fields has additional challenges, which can lead to treatment inconsistencies if not done properly. Most important is the use of an appropriate detector, as well as the application of the necessary corrections. The International Atomic Energy Agency and the American Association of Physicists in Medicine provide the International Code of Practice (CoP) TRS-483 for the dosimetry of small static fields used in external MV photon beams. It gives guidelines on how to apply small-field correction factors for small field dosimetry. The purpose of this study was to evaluate the impact of inaccurate small-field output factors on clinical brain stereotactic radiosurgery plans with and without applying the small-field correction factors as suggested in the CoP. Small-field correction factors for a Varian TrueBeam linear accelerator were applied to uncorrected relative dose factors. Uncorrected and corrected clinical plans were created with two different beam configurations, 6 MV with a flattening filter (6 WFF) and 6 MV without a flattening filter (6 FFF). For the corrected plans, the planning target volume mean dose was 1.6 ± 0.9% lower with p

The synthetic cathinone α-pyrrolidinopentiophenone (α-PVP) has been associated with violent and/or bizarre public behavior in users. Association of such behavior with extended binges of drug use motivates additional investigation, particularly since a prior study found that half of male rats experience a binge of exceptionally high intake, followed by sustained lower levels of self-administration during the acquisition of intravenous self-administration (IVSA) of a closely related drug, 3,4-methylenedioxypyrovalerone. The binge-like acquisition pattern appeared to be novel for rat IVSA, thus the present study was designed to determine if this effect generalizes to IVSA of α-PVP in female rats. Female Wistar rats were trained in IVSA of α-PVP (0.05 mg/kg/inf) in experimental chambers that contained an activity wheel. Groups of animals were trained with the wheels fixed (No-Wheel group), fixed for the initial 5 days of acquisition or free to move throughout acquisition (Wheel group). The groups were next subjected to a wheel-access switch and then all animals to dose-substitution (0.0125-0.3 mg/kg/inf) with the wheels alternately fixed and free to move. Approximately half of the rats initiated their IVSA pattern with a binge day of exceptionally high levels of drug intake, independent of wheel access condition. Wheel activity was much lower in the No-Wheel group in the wheel switch post-acquisition. Dose-effect curves were similar for wheel-access training groups, for binge/no binge phenotypic subgroups and were not altered with wheel access during the dose-substitution. This confirms the high reinforcer efficacy of α-PVP in female rats and the accompanying devaluation of wheel activity as a naturalistic reward.

Aim: Theory and experiments strongly support the importance of interactive effects of multiple factors shaping biodiversity, although their importance rarely has been investigated at biogeographically relevant scales. In particular, the importance of higher order interactions among environmental factors at such scales is largely unknown. We investigated higher order interactions of environmental factors to explain diversity patterns in a metacommunity of aquatic invertebrates at a biogeo- graphically relevant scale and discuss the findings in an environmental management context. Location: All major drainage basins in Switzerland (Rhine, Rhone, Ticino and Inn; 41,285 km2). Methods: Riverine a-diversity patterns at two taxonomic levels (family richness of all benthic macroinvertebrates and species richness of Ephemeroptera, Plecoptera and Trichoptera) were examined at 518 sites across the basins. We applied a novel machine learning technique to detect key three-way interactions of explanatory variables by comparing the relative importance of 1,140 three-way combinations for family richness and 680 three-way combinations for species richness. Results: Relatively few but important three-way interactions were meaningful for predicting biodiversity patterns among the numerous possible combinations. Specifically, we found that interactions among elevational gradient, prevalence of forest coverage in the upstream basin and biogeoclimatic regional classification were distinctly important. Main conclusion: Our results indicated that a high prevalence of terrestrial forest generally sustains riverine benthic macroinvertebrate diversity, but this relationship varies considerably with biogeoclimatic and elevational conditions likely due to community composition of forests and macroinvertebrates changing along climatic and geographical gradients. An adequate management of riverine ecosystems at relevant biogeographical scales requires the identification of such interactions and a context-dependent implementation.

Leaf litter decomposition is a major ecosystem process that can link aquatic to terrestrial ecosystems by flows of nutrients. Biodiversity and ecosystem functioning research hypothesizes that the global loss of species leads to impaired decomposition rates and thus to slower recycling of nutrients. Especially in aquatic systems an understanding of diversity effects on litter decomposition is still incomplete. Here we conducted an experiment to test two main factors associated with global species loss that might influence leaf litter decomposition. Firstly, we tested whether mixing different leaf species alters litter decomposition rates compared to decomposition of these species in monoculture. Secondly, we tested the effect of the size structure of a lotic decomposer community on decomposition rates. Overall, leaf litter identity strongly affected decomposition rates, and the observed decomposition rates matched measures of metabolic activity and microbial abundances. While we found some evidence of a positive leaf litter diversity effect on decomposition, this effect was not coherent across all litter combinations and the effect was generally additive and not synergistic. Microbial communities, with a reduced functional and trophic complexity, showed a small but significant overall reduction in decomposition rates compared to communities with the naturally complete functional and trophic complexity, highlighting the importance of a complete microbial community on ecosystem functioning. Our results suggest that top-down diversity effects of the decomposer community on litter decomposition in aquatic systems are of comparable importance as bottom-up diversity effects of primary producers. This article is protected by copyright. All rights reserved.

An optically based sensing system that can measure the displacement and strain over essentially the entire area of a utility-scale blade leads to a measurement system that can significantly reduce the time and cost associated with traditional instrumentation. This paper evaluates the performance of conventional three dimensional digital image correlation (3D DIC) and three dimensional point tracking (3DPT) approaches over the surface of wind turbine blades and proposes a multi-camera measurement system using dynamic spatial data stitching. The potential advantages for the proposed approach include: (1) full-field measurement distributed over a very large area, (2) the elimination of time-consuming wiring and expensive sensors, and (3) the need for large-channel data acquisition systems. There are several challenges associated with extending the capability of a standard 3D DIC system to measure entire surface of utility scale blades to extract distributed strain, deflection, and modal parameters. This paper only tries to address some of the difficulties including: (1) assessing the accuracy of the 3D DIC system to measure full-field distributed strain and displacement over the large area, (2) understanding the geometrical constraints associated with a wind turbine testing facility (e.g. lighting, working distance, and speckle pattern size), (3) evaluating the performance of the dynamic stitching method to combine two different fields of view by extracting modal parameters from aligned point clouds, and (4) determining the feasibility of employing an output-only system identification to estimate modal parameters of a utility scale wind turbine blade from optically measured data. Within the current work, the results of an optical measurement (one stereo-vision system) performed on a large area over a 50-m utility-scale blade subjected to quasi-static and cyclic loading are presented. The blade certification and testing is typically performed using International Electro-Technical Commission standard (IEC 61400-23). For static tests, the blade is pulled in either flap-wise or edge-wise directions to measure deflection or distributed strain at a few limited locations of a large-sized blade. Additionally, the paper explores the error associated with using a multi-camera system (two stereo-vision systems) in measuring 3D displacement and extracting structural dynamic parameters on a mock set up emulating a utility-scale wind turbine blade. The results obtained in this paper reveal that the multi-camera measurement system has the potential to identify the dynamic characteristics of a very large structure.

History of Burma from the earliest times to 10 March, 1824, the beginning of the English conquest

The medial amygdala (MeA), bed nucleus of the stria terminalis (BNST), and medial preoptic area (mPOA) are important for the regulation of male sexual behavior. Sexual experience facilitates sexual behaviors and influences activity in these regions. The goal of this study was to determine whether sexual experience or copulation induces plasticity in the MeA, BNST, or mPOA of male rats, as indicated by changes in levels of Arc, which is indicative of activity-dependent synaptic plasticity in the brain. To this end, sexually naive or experienced males were placed in mating arenas either alone, with an inaccessible estrus female, or with an accessible estrus female. Arc protein levels were then quantified in these three regions using immunohistochemistry. As expected, sexual experience facilitated copulation, as evidenced by a reduction in latencies to mount, intromit, and ejaculate. Copulation also increased the number of Arc-positive cells in the MeA, anterior BNST, posterior BNST, and the posterior mPOA, but not in the central-rostral region of the mPOA. Surprisingly, prior sexual experience did not impact levels of Arc, suggesting that copulation-induced Arc occurs in both sexually naive and experienced males.

Assessing individual components of biodiversity, such as local or regional taxon richness, and differences in community composition is a long-standing challenge in ecology. It is especially relevant in spatially structured and diverse ecosystems. Environmental DNA (eDNA) has been suggested as a novel technique to accurately measure biodiversity. However, we do not yet fully understand the comparability of eDNA-based assessments to previously used approaches.We sampled may-, stone-, and caddisfly genera with contemporary eDNA and kicknet methods at 61 sites distributed over a large river network, allowing a comparison of various diversity measures from the catchment to site levels and providing insights into how these measures relate to network properties. We extended our survey data with historical records of total diversity at the catchment level.At the catchment scale, eDNA and kicknet detected similar proportions of the overall and cumulative historically documented species richness (gamma diversity), namely 42% and 46%, respectively. We further found a good overlap (62%) between the two contemporary methods at the regional scale.At the local scale, we found highly congruent values of local taxon richness (alpha diversity) between eDNA and kicknet. Richness of eDNA was positively related with discharge, a descriptor of network position, while kicknet was not.Beta diversity between sites was similar for the two contemporary methods. Contrary to our expectation, however, beta diversity was driven by species replacement and not by nestedness.Although optimization of eDNA approaches is still needed, our results indicate that this novel technique can capture extensive aspects of gamma diversity, proving its potential utility as a new tool for large sampling campaigns across hitherto understudied complete river catchments, requiring less time and becoming more cost-efficient than classical approaches. Overall, the richness estimated with the two contemporary methods is similar at both local and regional scale but community composition is differently assessed with the two methods at individual sites and becomes more similar with higher discharge.

Temperature is known to influence ecosystem processes through its direct effect on biological rates such as respiration and nutrient cycling. These changes can then indirectly affect ecologically processes by altering trophic dynamics, the persistence of a species in a given environment, and, consequently, its distribution. However, it is not known if this direct effect of temperature on biological rates is singularly the most important factor for the functioning of ecosystems, or if trophic structure and the adaptation of a species to the local environment also play an essential role. Understanding the relative importance of these factors is crucial for predicting the impact that climate change will have on species and ecosystems. To achieve a more complete understanding of the impact of changing temperatures, it is necessary to integrate perspectives from biogeography, such as the influences of species distribution and local adaptation, with ecosystem and community ecology. By using the microbial community inhabiting the water-filled leaves of Sarracenia purpurea, we tested the importance of temperature, trophic structure, and local adaptation on ecosystem functioning. We accomplished this by collecting communities along a natural temperature gradient and maintaining these communities in a common garden, factorial experiment. To test for the importance of local adaptation and temperature, the origin of each community was crossed with the temperature from each site. Additionally, to test the importance of top-down trophic regulation for ecosystem functioning, the presence of the mosquito larvae top predator was manipulated. We found that temperature has a greater effect on ecosystem functioning than origin, and that top-down trophic regulation increased with temperature. Our results emphasize the synergistic effects of temperature and biotic interactions when predicting the consequences of global warming on ecosystem functioning.

Recent reports on the abuse of novel synthetic cathinone derivatives call attention to serious public health risks of these substances. In response to this concern, a growing body of preclinical research has characterized the psychopharmacology of these substances, particularly mephedrone (MEPH) or methylenedioxypyrovalerone (MDPV), noting their similarities to 3,4-methylenedioxymethamphetamine (MDMA) and cocaine. Few studies have utilized drug discrimination methodology to characterize the psychopharmacological properties of these substances. The present study employed a rodent drug discrimination assay to further characterize the stimulus effects of MEPH and MDPV in comparison to MDMA and to a drug mixture comprised of d-amphetamine and MDMA. Eight male Sprague-Dawley rats were trained to discriminate 1.5 mg/kg MDMA, and eight rats were trained to discriminate a mixture of 1.5 mg/kg MDMA and 0.5 mg/kg d-amphetamine (MDMA + AMPH) from vehicle. Substitution tests were conducted with MDMA, d-amphetamine, MDPV, MEPH, and cocaine. Dose-response curves generated with MDMA and MEPH were comparable between training groups. In contrast, AMPH, MDPV, and cocaine produced only partial substitution in animals trained to discriminate MDMA but produced full substitution in animals trained to discriminate the MDMA + AMPH mixture. These findings indicate that MDPV’s effects may be more similar to those of traditional psychostimulants, whereas MEPH exerts stimulus effects more similar to those of MDMA. Additional experiments with selective DA and 5-hydroxytryptamine (5-HT) receptor antagonists are required to further elucidate specific receptor mechanisms mediating the discriminative stimulus effects of MDPV and mephedrone.

Background: Femoral tunnel positioning in anterior cruciate ligament reconstruction (ACLR) is an intricate procedure that requires highly specific surgical skills. Purpose: To report the ability of residents to identify femoral landmarks and the native ACL footprint before and after a structured formal teaching session as a reflection of overall surgical skill training for orthopaedic surgery residents in Canada. Study Design: Controlled laboratory study. Methods: A total of 13 senior orthopaedic residents were asked to identify a femoral landmark and an ACL footprint on ten 3-dimensional (3D)–printed knee models before and after a teaching session during the fall of 2018. The 3D models were made based on actual patients with different anatomic morphologic features. ImageJ software was used to quantify the measurements, which were then analyzed through use of descriptive statistics. Results: Before and after the teaching session, residents attempted to identify a specific anatomic location (bifurcate and intercondylar ridge intersection) with a mean error per participant ranging from 5.00 to 10.95 mm and 4.79 to 12.13 mm in magnitude, respectively. Furthermore, before and after the teaching session, residents identified the specific position to perform the surgical procedure (ACL femoral footprint), with a mean error per participant ranging from 4.58 to 8.80 mm and 3.87 to 11.07 mm in magnitude, respectively. The teaching session resulted in no significant improvement in identification of either the intersection of the bifurcate and intercondylar ridges ( P = .9343 in the proximal-distal axis and P = .8133 in the anteroposterior axis) or the center of the femoral footprint ( P = .7761 in the proximal-distal axis and P = .9742 in the anteroposterior axis). Conclusion: Although a formal teaching session was combined with a hands-on session that entailed real surgical instrumentation and fresh cadaveric specimens, the intervention seemed to have no direct impact on senior residents’ performance or their ability to demonstrate the material taught. This puts into question the format and efficacy of present teaching methods. Also, it is possible that the 3D spatial perception required to perform these skills is not something that can be taught effectively through a teaching session or at all. Further investigation is required regarding the effectiveness and application of surgical skill laboratories and simulations on the competencies of orthopaedic residents.

Moving beyond species count data is an essential step to better understand the effects of environmental perturbations on biodiversity and ecosystem functions, and to eventually better predict the strength and direction of those effects. Here, coupling an integrative path analysis approach with data from an extensive countrywide monitoring program, we tested the main spatial, environmental and anthropogenic drivers of change in the functional structure of aquatic macroinvertebrate communities along the entire Swiss Rhine river catchment. Functional structure was largely driven by inherent altitudinal variation influencing and cascading to regional scaled factors such as land use change and position in the riverine network, which, in turn, transformed local habitat structure variables. Those cascading effects across scales propagated through the biotic community, first affecting prey and, in turn, predators. Our results illustrate how seemingly less important local factors can act as essential transmission belts, propagating through direct and indirect pathways across scales to generate the specific context in which each functional group will strive or not, leading to characteristic landscape wide variations in functional community structure.

BackgroundElectronic nicotine delivery systems (ENDS, e-cigarettes) are increasingly used for the self-administration of nicotine by various human populations, including previously nonsmoking adolescents. Studies in preclinical models are necessary to evaluate health impacts of ENDS including the development of nicotine addiction, effects of ENDS vehicles, flavorants and co-administered psychoactive substances such as ∆9-tetrahydrocannabinol (THC). This study was conducted to validate a rat model useful for the study of nicotine effects delivered by inhalation of vapor created by ENDS.MethodsMale Sprague-Dawley rats (N=8) were prepared with radiotelemetry devices for the reporting of temperature and activity. Experiments subjected rats to inhalation of vapor generated by an electronic nicotine delivery system (ENDS) adapted for rodents. Inhalation conditions included vapor generated by the propylene glycol (PG) vehicle, Nicotine (1, 10, 30 mg/mL in the PG) and THC (12.5, 25 mg/mL).ResultsNicotine inhalation increased spontaneous locomotion and decreased body temperature of rats. Pretreatment with the nicotinic cholinergic receptor antagonist mecamylamine (2 mg/kg, i.p.) prevented stimulant effects of nicotine vapor inhalation and attenuated the hypothermic response. Combined inhalation of nicotine and THC resulted in apparently independent effects which were either additive (hypothermia) or opposed (activity).ConclusionsThese studies provide evidence that ENDS delivery of nicotine via inhalation results in nicotine-typical effects on spontaneous locomotion and thermoregulation in male rats. Effects were blocked by a nicotinic antagonist, demonstrating mechanistic specificity. This system will therefore support additional studies of the contribution of atomizer/wick design, vehicle constituents and/or flavorants to the effects of nicotine administered by ENDS.

Background Early screening for prostate cancer (PCA) remains controversial because of overdiagnosis and overtreatment of clinically insignificant cancers. Even though a number of diagnostic tests have been developed to improve on PSA testing, there remains a need for a more informative non-invasive test for PCA. The objective of this study is to identify a panel of DNA methylation markers suitable for a non-invasive diagnostic test from urine DNA collected following a digital rectal exam (DRE) and/or from first morning void (FV). A secondary objective is to determine if the cumulative methylation is indicative of biopsy findings. Methods DRE and FV urine samples were prospectively collected from 94 patients and analyzed using 24 methylation-specific quantitative PCR assays derived from 19 CpG islands. The methylation of individual markers and various combinations of markers was compared to biopsy results. A methylation threshold for cancer classification was determined using a target specificity of 70%. The average methylation and the number of positive markers were also compared to the result of the biopsy, and the area under the receiver operating characteristic curves (AUCs) were calculated. Results Methylation of all 19 markers was detected in FV and DRE DNAs. Combining the methylation of two or more markers improved on individual marker results. Using 6of19 methylated markers as the threshold for cancer classification yielded a specificity of 71% (95% CI, 0.57–0.86) from both DRE and FV and a sensitivity of 89% (95% CI, 0.79–0.97) from DRE and 94% (95% CI, 0.84–1.0) from FV. The negative predictive value at the 6of19 threshold was ≥ 90 for both DNA types. Conclusions PCA-specific methylation was detected in both FV and DRE DNA. There was no significant difference in diagnostic accuracy at the 6of19 threshold between DRE and FV urine DNA. The results support the development of a non-invasive diagnostic test to reduce unnecessary biopsies in men with elevated PSA. The test can also provide patients with personalized recommendations based on their own methylation profile. Electronic supplementary material The online version of this article (10.1186/s13148-018-0524-x) contains supplementary material, which is available to authorized users.

Drug-induced changes in gene expression likely contribute to long-lasting structural and functional alterations in the brain's reward circuitry and the persistence of addiction. Modulation of chromatin structure through covalent histone modifications has emerged as an important regulator of gene transcription in brain and increasing evidence suggests that misregulation of histone acetylation contributes to the establishment and maintenance of aberrant neuronal gene programs and behaviors associated with cocaine or amphetamine exposure. In this review, we summarize evidence supporting a role for histone acetylation in psychostimulant-induced plasticity and discuss findings from preclinical studies investigating histone deacetylase (HDAC) action and the use of small-molecule HDAC inhibitors (HDACis) to correct drug-mediated transcriptional dysregulation.

In response to the digitization and corporatization of the record industry, Record Store Day brands music consumption as an ethical decision, coordinating the release of exclusive vinyl records to independent, locally owned retailers and framing an engineered collectors’ market as an annual holiday. In this article, I evaluate Record Store Day as an ambivalent brand culture – a perspective highlighting the affective and relational components of brands without privileging exploitation or authenticity. At once, Record Store Day is a commercial platform for the development of media ideologies and political subject positions on independence and a capitalist operation that compartmentalizes its corporate intermediaries and offloads financial risk onto small stores. Record Store Day’s success suggests that ambivalent brand cultures provide a productive framework through which to analyse the political and cultural possibilities of media formats and independent retail.

Despite the MP3's ubiquity, the compressed audio file's presence in scholarly literature has been relatively scarce. Most often, the format has taken second place to the iPods and other gadgets des...

Psychopharmacology research has amassed substantial evidence for similarities between synthetic cathinones and other commonly abused psychostimulants. Few studies have utilized drug discrimination methods to investigate synthetic cathinones, and the precise neurochemical substrates underlying their interoceptive effects have not been examined. The present study assessed the involvement of D1 and D2 dopaminergic receptors in the stimulus effects of 3,4-methylenedioxypyrovalerone (MDPV) and mephedrone (MEPH) in rats trained to discriminate D-amphetamine. Eight male Sprague-Dawley rats were trained to discriminate 0.5 mg/kg D-amphetamine (AMPH) from saline. Dose-response curves were then generated with AMPH (0.0-1.0 mg/kg), MDPV (0.0-1.0 mg/kg), and MEPH (0.0-2.0 mg/kg). Subsequently, Sch 39166 (0.3 mg/kg) and haloperidol (0.5 mg/kg) were administered in combination with select doses of MDPV and MEPH. Both MDPV and MEPH produced full substitution for AMPH. Sch 39166 produced a downward shift in the MDPV and MEPH dose-response curves and haloperidol produced similar results with MDPV. These preliminary findings indicate that MDPV and MEPH produce interoceptive stimuli that are similar to those produced by AMPH and that D1 and D2 dopamine receptors contribute to these effects. Additional studies are warranted to investigate the contribution of other receptor mechanisms involved in the interoceptive stimuli produced by synthetic cathinones.

Food webs assemble via the interacting constraints of dispersal limitation and bottom-up trophic dependencies where consumers can only establish after their resources have arrived. These factors can affect assembly by influencing the expression of the regional species pool in local patches, but how this unfolds mechanistically remains unclear. Here, we use a large-scale grassland meta-community experiment to demonstrate how the independent influences of spatial factors and bottom-up constraints on insect trophic guilds interact to create divergent local insect communities. Bottom-up trophic dependencies tightly controlled the composition and abundance of specialist trophic guilds, resulting in different communities among islands because producer communities were mainly determined by patch size contingencies. Spatial isolation controlled the composition and abundance of generalist trophic guilds, resulting in different insect communities among islands based on distance from mainland. These results demonstrate that neither diet-based constraints nor the spatial characteristics of islands can predict the early structure of locally assembling food webs, with their establishment deriving instead from interactions between both processes.

A recommendation of: Tadeu Siqueira, Victor S. Saito, Luis M. Bini, Adriano S. Melo, Danielle K. Petsch, Victor L. Landeiro, Kimmo T. Tolonen, Jenny Jyrkankallio-Mikkola, Janne Soininen, Jani Heino Community size affects the signals of ecological drift and selection on biodiversity 10.1101/515098

Measured data from operating systems are often acquired to predict structural health of a system. With only a few measurement sensors, very limited understanding of the system can be obtained. Utilizing some recent novel expansion results, full field information can be obtained to identify a more complete strain description for the system. Using these results in conjunction with an analytical prediction of the expected strains, comparisons and differences can be identified using time response data. The expected full field stress-strain from the analytical model is compared to the predicted full field dynamic stress strain from limited sets of measured locations due to either operating or imposed loading on the structure. Differences in strain distributions at many time increments can provide indications of regions of possible damage in the structure. The work presented in this paper identifies the methodology as well as some results to illustrate the usefulness of the approach.

Understanding the impacts of species extinctions on the functioning of food webs is a challenging task because of the complexity of ecological interactions. We report the impacts of experimental species extinctions on the functioning of two food webs of freshwater and marine systems. We used a linear model to partition the variance among the multiple components of the diversity effect (linear group richness, nonlinear group richness, and identity). The identity of each functional group was the best explaining variable of ecosystem functioning for both systems. We assessed the contribution of each functional group in multifunctional space and found that, although the effect of functional group varied across ecosystem functions, some functional groups shared common effects on functions. This study is the first experimental demonstration that functional identity dominates the effects of extinctions on ecosystem functioning, suggesting that generalizations are possible despite the inherent complexity of interactions.

Album leaks have become a taken-for-granted experience amongst artists, labels, and fans over the past decade. The cultural impact of leaks is obscured through a simple definition of piracy, however. Recordings encoded as mp3 files can escape established distribution networks and circulate in ways that performatively instantiate new interpretive communities with unique practices of anticipation, access, and evaluation. Using two incidents from the weeks leading up to the release of Animal Collective’s highly anticipated 2009 release Merriweather Post Pavilion, I contend that the practices and media technologies governing leaks transfigure the form and function of recordings, raising important questions about music promotion and fandom. In the first incident, a leaked song ripped from a podcast and endorsed on another artist’s blog triggers the involvement of a web security firm, blurring distinctions between promotion and piracy. In the second incident, members of a music messageboard create a fake leak to fool eager Animal Collective fans, exploiting the modular affordances of the mp3 to enforce their own rules of affective propriety for enthusiastic leak-seekers.

Traditional ply-based and zone-based models are limited in their ability to account for the fiber directions resulting from the forming of fabric-reinforced composite wind turbine blades. Compounding the problem is the presence of defects such as resin-rich pockets of the polymer matrix due to out-of-plane and in-plane waves resulting from the manufacturing process. As a result, blades are typically overdesigned, unnecessarily increasing weight and material costs. In the current research, a methodology is presented for simulating the manufacturing process for fabric-reinforced composite wind turbine blades using ABAQUS/Explicit. The methodology captures the evolution of the yarn directions during the forming process thereby allowing for a map of the fiber orientations throughout the blade. A hybrid approach using conventional beam and shell elements is used to model the various fabric layers. Using experimental shear, tensile, bending, and friction data to characterize the mechanical behavior of the fabric layers, the model captures in-plane yarn waviness and changes in the in-plane yarn orientations as they conform to the shape of the mold, as well as out-of-plane wave defects as a result of the manufacturing process. Subsequently, after the fabric layers have been laid into the mold and the final yarn orientations are known, the structural stiffness of the blade resulting from the resin-infused fabrics can be calculated. The methodology can thereby link the resulting bending and torsional stiffnesses of the blade back to the manufacturing process. This paper discusses the methodology for determining the material properties of the beam and shell elements in their final orientations in the cured composite to predict the structural stiffness of a wind turbine blade.

Recent studies have focused attention on the possibility that hyperglycemia in the hospital is not a benign condition and that aggressive treatment of diabetes mellitus and hyperglycemia results in reduced morbidity and, in some cases, reduced mortality.[1][1]–[3][2] Stress-induced hyperglycemia

Objectives To explore the efficacy and safety of intravenous (IV) hydralazine in hospitalized children with hypertension. Study design Data were retrospectively collected on hospitalized children treated with IV hydralazine. Percent changes in blood pressure (BP) were calculated, and linear regression was used to investigate associations between BP change and pertinent clinical and demographic variables. Bivariate logistic regression was used to investigate associations between the same covariates and the outcomes of ideal clinical response (ICR), a 10%-25% reduction in mean arterial pressure (MAP), and excess response (ER), a 25% reduction in MAP. Results A total of 141 initial doses of IV hydralazine (median dose, 0.10 mg/kg [IQR, 0.09-0.11; range, 0.02-0.37]) were analyzed. Median age was 8 years (IQR, 2-15; range, 0-24); most patients had renal disease, malignancy, or were organ transplant recipients. The mean MAP reduction was 19% ± 12%. An ICR occurred in 66 patients (47%). Higher initial MAP and increased hydralazine dose were associated with greater percentage decrease in MAP. No association was found between ICR and the covariates of interest; higher initial MAP was associated with greater odds of ICR. ER occurred in 44 children (31%). Among this group, higher initial MAP and higher hydralazine dose were associated with increased odds of ER, and administration of other antihypertensive drugs was associated with decreased odds of ER. Four adverse effects possibly related to IV hydralazine, including 2 episodes of hypotension, were recorded. Conclusions IV hydralazine reduced BP in the majority of children. However, a substantial proportion of children experienced potentially excessive BP reduction.

Objective Symptomatic malignant pleural effusions are common sequelae in patients with certain malignancies. Pleurodesis via bedside thoracostomy is the current treatment option most commonly used. To our knowledge, this is the first prospective randomized trial to examine which agent, bleomycin or talc slurry, is superior in terms of effectiveness, safety, and cost. Patients and Methods Between July 1992 and March 1995, 35 patients presenting to our medical center with symptomatic malignant pleural effusions were prospectively randomized to undergo chemical pleurodesis with either bleomycin or talc slurry via bedside thoracostomy. The conditions of patients were assessed and graded before and after treatment concerning pain, dyspnea, and chest radiographs. Results Twenty-nine patients who underwent 33 treatments (14 with bleomycin and 19 with talc) were available for follow-up. Follow-up ranged from 2 weeks to 8 months (mean, 1.7 months). Both groups demonstrated notable improvement in both pain and dyspnea following treatment, but there were no statistically significant differences between groups in the amount of improvement (two-tailed Student's t test). Permanent control of effusions, defined objectively on chest radiograph, was achieved with 11 bleomycin treatments (79%) and 17 talc treatments (90%) (p=0.388). The procedures were well tolerated and no significant adverse effects were observed. Talc is a much less costly agent than bleomycin ($12.36 cost to our medical center per treatment for talc vs $955.83 for bleomycin). Conclusions Given the similar efficacy and significant cost advantage, we conclude that talc is the agent of choice when utilizing pleurodesis for control of symptomatic malignant pleural effusions.

There is an urgent need to develop predictive indicators of the effect of species loss on ecosystem functioning. Body size is often considered as a good indicator because of its relationship to extinction risk and several functional traits. Here, we examined the predictive capacity of species body size in marine and freshwater multitrophic systems. We found a significant, but weak, effect of body size on functioning. The effect was much stronger when considering the effect of body size within trophic position levels. Compared to extinctions ordered by body size, random extinction sequences had lower multiple species loss effects on functioning. Our study is the first to show experimentally, in multitrophic systems, a more negative impact of ordered extinction sequences on ecosystem functioning than random losses. Our results suggest apparent ease in predicting species loss effect on functioning based on easily measured ecological traits that are body size and trophic position.

We present spectrograph design details and initial radial velocity results from the PRL optical fiber-fed high-resolution cross-dispersed echelle spectrograph (PARAS), which has recently been commissioned at the Mt Abu 1.2 m telescope, in India. Data obtained as part of the post-commissioning tests with PARAS show velocity precision better than 2m/s over a period of several months on bright RV standard stars. For observations of sigma-Dra we report 1.7m/s precision for a period of seven months and 2.1m/s for HD 9407 over a period of 2 months. PARAS is capable of a single-shot spectral coverage of 3800A - 9500A at a resolution of about 67,000. The RV results were obtained between 3800A and 6900A using simultaneous wavelength calibration with a Thorium-Argon (ThAr) hollow cathode lamp. The spectrograph is maintained under stable conditions of temperature with a precision of 0.01 - 0.02C (rms) at 25.55C, and enclosed in a vacuum vessel at pressure of 0.1 +/-0.03 mbar. The blaze peak efficiency of the spectrograph between 5000A and 6500A, including the detector, is 30%; and about 25% with the fiber transmission. The total efficiency, including spectrograph, fiber transmission, focal ratio degradation (FRD), and telescope (with 81% reflectivity) is about 7% in the same wavelength region on a clear night with good seeing conditions., Comment: 33 pages, 15 figures, accepted for publication in PASP