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Introduction: The ability of living organisms to acquire the nutrients needed to carry out required physiological functions has important consequences for fitness. However, an organism must not simply meet the requirements for individual nutrients, but must ingest an optimal balance of multiple nutrients. Despite this, animals rarely consume truly balanced resources, and instead commonly feed selectively across multiple unbalanced resources to reach an optimal balance, i.e., intake target. Nutritional research has predominantly focused on the behavioral strategies employed during nutrient regulation, as well as the fitness consequence of failing to meet intake targets, but little work has been done on the temporal aspects of this process. For instance, within what timeframe must organisms reach their intake target before a fitness cost is incurred? Hours, days, weeks?, Methods: In this study, we investigated how nutrient regulation interval impacts consumption and performance in adult female spotted-wing Drosophila (Drosophila suzukii). Females were constrained to either a protein- orcarbohydrate-biased diet over different time intervals and at different schedules, while control flies were constrained to one diet for the entire feeding period., Results: Regulation interval had a significant impact on feeding behavior and consumption. Total consumption was highest on the shorter interval treatments, where diets were alternated more frequently, and declined as the interval period increased. The relative consumption of both diets was statistically-different across intervals and was higher for the carbohydrate-biased diet. Consumption of the protein-biased diet was more variable across intervals and was more strongly impacted by the daily timing of diet switches. Performance data showed that shorter regulation intervals led to longer fly lifespans, a result commonly observed in studies exploring the impacts of diet macronutrient ratio variability on performance., Discussion: These results show that the temporal aspects of nutrition, such as feeding intervals and the timing of resource availability, can have strong impacts on feeding behavior, nutrient regulation, and fitness. These results provide an insight into how consumers may deal with changes in host phenology, the availability of hosts, and changes in nutrient availability within hosts. Understanding these mechanisms will be important for predicting responses to changes in nutrient cycling and resource availability mediated by natural and anthropogenic habitat modifications, such as global climate change., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author WH declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2023 Deans and Hutchison.)

Background: Larger head-to-neck ratio of dual mobility (DM) hip arthroplasties provide greater range of motion/less risk of dislocation, but raise concerns for high wear and friction. We measured in vitro, the wear rates of contemporary DM hips with highly cross-linked ultra high molecular weight polyethylene (UHWMPE), where it came from, and their frictional torques., Methods: Hip simulators were used to compare the wear of DM to fixed-bearing (FB) designs of 2 different implants. Each of 8 different configurations underwent millions of simulated walking cycle tests, some as full DM, some as FB controls, some DM with the outer-articulation deliberately immobilized, and some the inner. Wear and 3-dimensional-frictional torques were measured and friction independent of size was deduced., Results: The DM hips produced lower wear and friction-torque than the FB hips. The DM wear during walking gait comes mostly from the smaller inner articular surface. If the outer surface was immobilized, the wear and torque of the inner alone would be small, but the full DM (inner and outer free-to-move) wear and torque were smallest of all. Friction measurements expectedly showed larger hips having higher frictional torques, but the DM showed the lowest, again because its motion was mostly the smaller inner articulation; smaller than even a modern fixed-bearing hip., Conclusion: The DM hips appear to combine the benefits of greater range of motion and less impingement of larger hips, with the lower wear and friction of smaller FB hips, with some benefits compromised if the outer or inner articulations are immobilized., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Over the past 14 years, the invasive vinegar fly, spotted-wing drosophila (Drosophila suzukii), has become one of the most damaging fruit pests in the United States. With regional economic losses estimated as high as $500 million for moderate infestations, D. suzukii control represents an often-untenable cost to growers. Management relies heavily on chemical control, which may be applied up to nine times in one season. The widespread use of chemical controls has led to concerns about insecticide resistance, and resistant field populations have already been documented in California and Michigan., Results: We cultured sub-populations of three different Minnesota field populations of D. suzukii in the laboratory and exposed them to increasing concentrations of two commonly-used insecticides, zeta-cypermethrin (pyrethroid) and spinetoram (spinosyn). Over the exposure period, the sub-populations experienced an 8- to 45-fold increase in insecticide concentration. We saw significant increases in the median lethal concentration (LC 50 ) values of one sub-population exposed to zeta-cypermethrin and one exposed to spinetoram. Across the spinetoram exposures, we also observed significant reductions in the top mortality values for three different sub-populations., Conclusion: Our results suggest that field populations of D. suzukii can develop resistance to zeta-cypermethrin and spinetoram in short periods of time under laboratory selection but that resistance to spinosyns occurs more readily than to pyrethroids. These results support other studies that have documented spinosyn resistance in field populations and in laboratory selections. Resistance evolution to spinosyns is a particularly important issue, as they represent one of few organic insecticide options for D. suzukii. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., (© 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.)

Although insecticide formulations and spray rates are optimized to achieve lethal exposure, there are many factors in agricultural settings that can reduce the effective exposure of insect pests. These include weather patterns, timing of application, chemical degradation/volatilization, plant structural complexity, and resistant populations. While sub-lethal exposure to insecticides can still have negative impacts on pest populations, they can also lead to stimulatory, or hormetic, responses that can increase the fitness of surviving insects. Sub-lethal concentrations may also produce increased tolerance in the offspring of surviving adults through transgenerational effects. Sub-lethal effects are pertinent for the invasive fruit pest, spotted-wing Drosophila, Drosophila suzukii (Matsumura), because its small size, diurnal movement patterns, and utilization of hosts with complex plant structures, such as caneberries and blueberries, make effective insecticide applications tenuous. In this study, we measured spotted-wing Drosophila survivorship, reproductive performance, and offspring tolerance in flies exposed to sub-lethal concentrations of three commonly-used insecticides (zeta-cypermethrin, spinetoram, and pyrethrin). We found some evidence for hormesis, with survival effects being sex- and concentration-dependent for all insecticides. Males were far more susceptible to insecticides than females, which in some cases exhibited higher eclosion success and reproductive rates when exposed to sub-lethal doses. We did not observe significant transgenerational effects at sub-lethal concentrations, despite trends of increased offspring viability for zeta-cypermethrin and spinetoram. More research, however, is needed to fully understand the role that sub-lethal effects may play in pest population dynamics, insecticide efficacy, and the development of genetic resistance., Competing Interests: The authors have declared that no competing interests exist.

Spotted-wing drosophila (SWD), Drosophila suzukii , has become one of the most widely studied insect species over the last decade, largely due to its recent invasion and rapid expansion across the Americas and Europe. Unlike other drosophilid species, which colonize rotting fruit, SWD females possess a serrated ovipositor that allows them to lay eggs in intact ripening fruit, causing significant economic problems for fruit/berry producers worldwide. Though an impressive amount of research has been conducted on SWD's ecology and physiology, aspects of their nutritional ecology remain ambiguous. This review synthesizes the research to date to provide a more comprehensive view of SWD's nutritional relationship with its fruit hosts and associated microbes. Overall, data suggest that SWD's ability to utilize novel resources is likely due to changes in their ecological, rather than physiological, niche that are largely mediated by microbial associations. Studies show that SWD's nutrient intake is comparable to other drosophilid species, indicating limited adaptation to feeding on lower-protein resources. Instead, data show that fruit protein content is a reliable predictor of host suitability and that fruit-microbe dynamics have a strong impact on protein availability. In particularly, fruit protein increases after infestation with SWD-associated microbes, suggesting that initially-suboptimal intact fruits can become protein-rich on a timeframe that is relevant for larval nutrition. This body of work suggests that microbial associations between flies and their fruit hosts can compensate for the nutritional differences between intact and rotting fruit, and that these relationships are likely responsible for SWD's expanded nutritional niche., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Deans and Hutchison.)

Anticipation is the act of using information about the past and present to make predictions about future scenarios. As a concept, it is predominantly associated with the psychology of the human mind; however, there is accumulating evidence that diverse taxa without complex neural systems, and even biochemical networks themselves, can respond to perceived future conditions. Although anticipatory processes, such as circadian rhythms, stress priming, and cephalic responses, have been extensively studied over the last three centuries, newer research on anticipatory genetic networks in microbial species shows that anticipatory processes are widespread, evolutionarily old, and not simply reserved for neurological complex organisms. Overall, data suggest that anticipatory responses represent a unique type of biological processes that can be distinguished based on their organizational properties and mechanisms. Unfortunately, an empirically based biologically explicit framework for describing anticipatory processes does not currently exist. This review attempts to fill this void by discussing the existing examples of anticipatory processes in non-cognitive organisms, providing potential criteria for defining anticipatory processes, as well as their putative mechanisms, and drawing attention to the often-overlooked role of anticipation in the evolution of physiological systems. Ultimately, a case is made for incorporating an anticipatory framework into the existing physiological paradigm to advance our understanding of complex biological processes., Competing Interests: The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Deans.)

Background: Cancer-associated weight loss (WL) associates with increased mortality. International consensus suggests that WL is driven by a variable combination of reduced food intake and/or altered metabolism, the latter often represented by the inflammatory biomarker C-reactive protein (CRP). We aggregated data from Canadian and European research studies to evaluate the associations of reduced food intake and CRP with cancer-associated WL (primary endpoint) and overall survival (OS, secondary endpoint)., Methods: The data set included a total of 12,253 patients at risk for cancer-associated WL. Patient-reported WL history (% in 6 months) and food intake (normal, moderately, or severely reduced) were measured in all patients; CRP (mg/L) and OS were measured in N = 4960 and N = 9952 patients, respectively. All measures were from a baseline assessment. Clinical variables potentially associated with WL and overall survival (OS) including age, sex, cancer diagnosis, disease stage, and performance status were evaluated using multinomial logistic regression MLR and Cox proportional hazards models, respectively., Results: Patients had a mean weight change of -7.3% (±7.1), which was categorized as: ±2.4% (stable weight; 30.4%), 2.5-5.9% (19.7%), 6.0-10.0% (23.2%), 11.0-14.9% (12.0%), ≥15.0% (14.6%). Normal food intake, moderately, and severely reduced food intake occurred in 37.9%, 42.8%, and 19.4%, respectively. In MLR, severe WL (≥15%) (vs. stable weight) was more likely (P < 0.0001) if food intake was moderately [OR 6.28, 95% confidence interval (CI 5.28-7.47)] or severely reduced [OR 18.98 (95% CI 15.30-23.56)]. In subset analysis, adjusted for food intake, CRP was independently associated (P < 0.0001) with ≥15% WL [CRP 10-100 mg/L: OR 2.00, (95% CI 1.58-2.53)] and [CRP > 100 mg/L: OR 2.30 (95% CI 1.62-3.26)]. Diagnosis, stage, and performance status, but not age or sex, were significantly associated with WL. Median OS was 9.9 months (95% CI 9.5-10.3), with median follow-up of 39.7 months (95% CI 38.8-40.6). Moderately and severely reduced food intake and CRP independently predicted OS (P < 0.0001)., Conclusions: Modelling WL as the dependent variable is an approach that can help to identify clinical features and biomarkers associated with WL. Here, we identify criterion values for food intake impairment and CRP that may improve the diagnosis and classification of cancer-associated cachexia., (© 2021 The Authors. Journal of Cachexia, Sarcopenia and Muscle published by John Wiley & Sons Ltd on behalf of Society on Sarcopenia, Cachexia and Wasting Disorders.)

Military and veteran populations may exhibit heightened vulnerability to gambling problems; however, there is scant relevant evidence outside the US, and few studies of transition periods, including return from operational deployment. The aim of this study was thus to highlight the extent, risk-factors, and implications of gambling problems among current members of the Australian Defence Force (ADF) following deployment to the Middle East Area of Operations (MEAO). It involved analyses of data from n = 1324 ADF personnel who deployed between 2010 and 2012, and completed surveys within four months of returning to Australia. The Problem Gambling Severity Index (PGSI) identified Problem Gambling (PG: PGSI ≥5) and At-Risk Gambling (ARG: PGSI 1-4), alongside measures of Depression (PHQ-9), Posttraumatic Stress Disorder (PCL-C), alcohol use problems (AUDIT), distress (K10), and post-deployment stressors. Analyses indicated that 7.7% of personnel reported at least some gambling problems post-deployment, including 2.0% that were distinguished by PG, and 5.7% indicating ARG. These figures were comparable to conditions including probable depression and alcohol dependence, while levels of any gambling problems were high relative to harmful drinking. Higher levels were observed among personnel who were aged 18-24, reported 0-4 years of military service, served in the Army, and comprised Non-Commissioned Officers/Other Ranks. There were strong associations with gambling problems and various indicators of mental health and wellbeing, and self-reported post-deployment difficulties. The findings indicate that gambling problems are salient concerns for some Australian military personnel post-deployment, and highlight the need for increased recognition and responses to these problems., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Case: We present a 51-year-old woman with Aitken A proximal femoral focal deficiency (PFFD) managed with total hip arthroplasty (THA). This patient presented with a history of disabling hip arthritis and multiple operations to improve her proximal femoral deformity and maintain a reduced hip. The hip was dysplastic with persistent femoral deformity, erosive acetabular changes, and abductor weakness. The surgical treatment was a THA., Conclusion: In the setting of hip arthritis, despite abductor weakness and deformity of the proximal femur, hip arthroplasty is a viable option for management of the patient with Aitken A PFFD.

Therapists and counsellors who provide trauma-focussed therapy and support to refugees and asylum seekers are often exposed to distressing and confronting stories of war, violence, torture, loss and grief, and other atrocities. In addition to this, working within an immigration and detention context has been reported to further contribute to experiences of burnout, vicarious trauma, and other adverse consequences of working with traumatised populations. There is a scarcity of research seeking to understand how therapists address these difficulties and maintain well-being to help them continue in this field of work. This mixed-methods research aimed to identify and explore factors associated with mental health and well-being among workers, with a particular focus on the role of clinical supervision. Participants were staff (n = 50) who identified as providing therapeutic support to refugees and asylum seekers either in Australia or in Australian-run detention facilities. Participants took part in an anonymous online survey which focussed on the psychological impact of their work, professional quality of life, and clinical supervision and incorporated free-text items. Thematic analysis of free-text data revealed four themes related to maintaining well-being at work including relationships and support seeking; physical and contemplative practices; professional growth; and balance and boundaries. Results from the quantitative analyses revealed several variables related to supervision that were important for well-being. In particular, the findings suggest that rapport and overall alliance with one's clinical supervisor are protective of secondary traumatic stress and depression, respectively. Important aspects of supervision were also explored in greater depth through qualitative and quantitative inquiry, increasing our understanding of the mechanisms underlying the relationship between clinical supervision and mental health and well-being for this group., (© 2020 John Wiley & Sons Ltd.)

Introduction: To evaluate the effects of a trauma performance improvement project involving standardized protocols for the administration of antibiotics in open fractures at a level one trauma center. This study specifically evaluated the protocol's efficacy for improving the timing of delivery and appropriate therapy administration and sought to identify factors that lead to the delay in antibiotic delivery., Methods: Retrospective comparative cohort study comparing patients with open fractures treated at our hospital between January 2013 and September 2015 (group 1) and between April 2016 and June 2017 (group 2). Group 1 was treated before implementation of the performance improvement project and group 2 was treated after implementation., Results: Group 1 consisted of 79 patients and group 2 consisted of 80 patients with open fractures. Each group was statistically similar in patient and injury factors. Group 1 received antibiotics at an average of 97 minutes after arrival to our hospital while group 2 patients received them at an average of 46 minutes (P < 0.0001). Average time from admission to initial evaluation improved from 10 to 3 minutes (P < 0.0001). Average time from evaluation to antibiotic order placement improved from 77 to 26 minutes (P < 0.0001). Average time from order entry to antibiotic administration showed no significant difference (12 versus 15 minutes, P = 0.25). Thirty-four percent (27/79) of group 1 patients and 84% (67/80) of group 2 patients received antibiotics within 1 hour of admission (P < 0.0001), while 91% and 99% received antibiotics within 3 hours, respectively (P = 0.03)., Discussion: The described multifaceted performance improvement protocol was highly effective for producing a more coordinated, efficient, and timely process for administration of antibiotics to patients with open fractures at our hospital. This protocol may be adopted and implemented at other facilities., Level of Evidence: Therapeutic level III.

Introduction: Surgery (oesophagectomy), with neoadjuvant chemo(radio)therapy, is the main curative treatment for patients with oesophageal cancer. Several surgical approaches can be used to remove an oesophageal tumour. The Ivor Lewis (two-phase procedure) is usually used in the UK. This can be performed as an open oesophagectomy (OO), a laparoscopically assisted oesophagectomy (LAO) or a totally minimally invasive oesophagectomy (TMIO). All three are performed in the National Health Service, with LAO and OO the most common. However, there is limited evidence about which surgical approach is best for patients in terms of survival and postoperative health-related quality of life., Methods and Analysis: We will undertake a UK multicentre randomised controlled trial to compare LAO with OO in adult patients with oesophageal cancer. The primary outcome is patient-reported physical function at 3 and 6 weeks postoperatively and 3 months after randomisation. Secondary outcomes include: postoperative complications, survival, disease recurrence, other measures of quality of life, spirometry, success of patient blinding and quality assurance measures. A cost-effectiveness analysis will be performed comparing LAO with OO. We will embed a randomised substudy to evaluate the safety and evolution of the TMIO procedure and a qualitative recruitment intervention to optimise patient recruitment. We will analyse the primary outcome using a multi-level regression model. Patients will be monitored for up to 3 years after their surgery., Ethics and Dissemination: This study received ethical approval from the South-West Franchay Research Ethics Committee. We will submit the results for publication in a peer-reviewed journal., Trial Registration Number: ISRCTN10386621., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. Published by BMJ.)

Lygus bugs are highly polyphagous piercing/sucking insects found throughout North America. Collectively, they have been reported to feed on over 330 plant species (one of the broadest host range ever documented for a group of insects); they also feed on many economically important crops. Despite its prevalence across North America and status as a common pest in many agroecosystems, very little is known about how Lygus bugs regulate their intake of nutrients. In reality, little is known about nutrient regulation for most hemipterans, specifically non-phloem feeding species in the suborder Heteroptera. This likely reflects difficulties in developing adequate artificial diets for insects with piercing/sucking mouthparts. There is, however, an artificial diet for L. hersperus, and in this study we modified it and performed choice and no-choice experiments to determine how L. hesperus regulates its intake of two macronutrients - protein (p) and carbohydrates (c) - that are tightly linked to survival and performance in other insect herbivores. In choice experiments L. hesperus was allowed to select between two foods with different protein:carbohydrate ratios. We documented strong regulation for protein and carbohydrates, with late instar nymphs selecting a slightly protein-biased intake target (protein-carbohydrate ratio = 1.5:1). We also performed no-choice experiments, where nymphs were restricted to a single food. Here, the protein-carbohydrate ratio of their food had a strong impact on survival, which was highest for nymphs reared on the treatment with a protein-carbohydrate ratio closest to the self-selected intake target (determined by the choice experiments), but no significant impact on developmental time or mass gain. Our data are the first of their kind for a non-phloem feeding hemipteran and provide a starting point for more broadly understanding and further investigating the nutritional ecology/physiology of Lygus bugs. Our study also provides a framework for exploring nutrient regulation in other hemipterans and for optimizing artificial diets for piercing/sucking insects, especially heteropterans., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

This article reports on a research project investigating psychology graduate students' experiences of Y model psychotherapy training at an Australian university. Focus group interviews were conducted with clinical psychology students (N=20), and thematic analysis was used to capture core aspects of their training experience. Participants felt that the dual training in cognitive-behavioral therapy and psychodynamic therapy gave them a significant advantage over students trained in only a single approach. Notwithstanding the perceived benefits of their training, participants emphasized how intellectually and emotionally demanding it was. Students struggled to shift between therapeutic orientations, both in learning about and conducting different therapies and in accommodating differing supervisory expectations. Psychodynamic therapy was viewed as the most conceptually, technically, and personally challenging component to learn, but also as the most enriching. Despite the emphasis the students placed on the psychodynamic arm of the Y model training, participants reported a variety of therapeutic identity positions, and most maintained a flexible view of how they would practice therapeutically.

We report on a single-channel rubidium radio-frequency atomic magnetometer operating in unshielded environments and near room temperature with a measured sensitivity of 130 fT/ Hz . We demonstrate consistent, narrow-bandwidth operation across the kHz-MHz band, corresponding to three orders of magnitude of the magnetic field amplitude. A compensation coil system controlled by a feedback loop actively and automatically stabilizes the magnetic field around the sensor. We measure a reduction in the 50 Hz noise contribution by an order of magnitude. The small effective sensor volume, 57 mm 3 , increases the spatial resolution of the measurements. Low temperature operation, without any magnetic shielding, coupled with the broad tunability, and low beam power, dramatically extends the range of potential field applications for our device.

We report on a 2×2 array of radio-frequency atomic magnetometers in a magnetic induction tomography configuration. Active detection, localization, and real-time tracking of conductive, nonmagnetic targets are demonstrated in air and saline water. Penetration in different media and detection are achieved thanks to the sensitivity and tunability of the sensors, and to the active nature of magnetic induction probing. We obtained a 100% success rate for automatic detection and a 93% success rate for automatic localization in air and water, up to 190 mm away from the sensor plane (100 mm underwater). We anticipate magnetic induction tomography with arrays of atomic magnetometers finding applications in civil engineering and maintenance, the oil and gas industry, geological surveys, marine science, archeology, search and rescue, and security and surveillance.

We demonstrate identification of position, material, orientation, and shape of objects imaged by a ^{85}Rb atomic magnetometer performing electromagnetic induction imaging supported by machine learning. Machine learning maximizes the information extracted from the images created by the magnetometer, demonstrating the use of hidden data. Localization 2.6 times better than the spatial resolution of the imaging system and successful classification up to 97% are obtained. This circumvents the need of solving the inverse problem and demonstrates the extension of machine learning to diffusive systems, such as low-frequency electrodynamics in media. Automated collection of task-relevant information from quantum-based electromagnetic imaging will have a relevant impact from biomedicine to security.

We demonstrate the penetration of thick metallic and ferromagnetic barriers for imaging of conductive targets underneath. Our system is based on an 85 Rb radio-frequency atomic magnetometer operating in electromagnetic induction imaging modality in an unshielded environment. Detrimental effects, including unpredictable magnetic signatures from ferromagnetic screens and variations in the magnetic background, are automatically compensated by active compensation coils controlled by servo loops. We exploit the tunability and low-frequency sensitivity of the atomic magnetometer to directly image multiple conductive targets concealed by a 2.5 mm ferromagnetic steel shield and/or a 2.0 mm aluminium shield, in a single scan. The performance of the atomic magnetometer allows imaging without any prior knowledge of the barriers or the targets, and without the need of background subtraction. A dedicated edge detection algorithm allows automatic estimation of the targets' size within 3.3 mm and of their position within 2.4 mm. Our results prove the feasibility of a compact, sensitive and automated sensing platform for imaging of concealed objects in a range of applications, from security screening to search and rescue.

We demonstrate remote detection of rotating machinery, using an atomic magnetometer at room temperature and in an unshielded environment. The system relies on the coupling of the AC magnetic signature of the target with the spin-polarized, precessing atomic vapor of a radio-frequency optical atomic magnetometer. The AC magnetic signatures of rotating equipment or electric motors appear as sidebands in the power spectrum of the atomic sensor, which can be tuned to avoid noisy bands that would otherwise hamper detection. A portable apparatus is implemented and experimentally tested. Proof-of-concept investigations are performed with test targets mimicking possible applications, and the operational conditions for optimum detection are determined. Our instrument provides comparable or better performance than a commercial fluxgate and allows detection of rotating machinery behind a wall. These results demonstrate the potential for ultrasensitive devices for remote industrial and usage monitoring, security, and surveillance.

Objective: To determine trends in crude and risk-adjusted mortality for major trauma patients injured in rural or metropolitan New South Wales, 2009-2014., Design: A retrospective analysis of NSW statewide trauma registry data., Participants: Adult patients (aged 16 years or more) who presented with major trauma (Injury Severity Scores greater than 15) to a NSW hospital during 2009-2014., Main Outcome Measures: The main covariate of interest was geographic location of injury (metropolitan v rural/regional areas). Inpatient mortality was analysed by multivariable logistic regression., Results: Data for 11 423 eligible patients were analysed. Inpatient mortality for those injured in metropolitan locations was 14.7% in 2009 and 16.1% in 2014 (P = 0.45). In rural locations, there was a statistically significant decline in in-hospital mortality over the study period, from 12.1% in 2009 to 8.7% in 2014 (P = 0.004). Risk-adjusted mortality for those injured in a rural location was lower in 2013 than during 2009, but remained stable for those injured in metropolitan locations., Conclusion: Crude and risk-adjusted mortality after major trauma have remained stable in those injured in metropolitan areas of NSW between 2009 and 2014. The apparent downward trend in mortality associated with severe trauma in rural/regional locations requires further analysis.

The widespread global adoption of Bt crops elevates concerns about the evolution of Bt resistance in insect pest species. Current insecticide resistance management (IRM) strategies focus solely on genetic variation as a causal factor in the evolution of resistance, but ignore the role that environmental factors, such as nutrition, may play. In this opinion paper, we discuss the benefits that insect herbivores gain from consuming foods with protein-carbohydrate content that matches their self-selected protein-carbohydrate intake, and show that even within monocultures there is amply opportunity for insect herbivores to regulate their macronutrient intake. Next we review new data that show that dietary protein and carbohydrates can: firstly, have predictably strong effects on the survival and performance of caterpillars challenged with Bt toxins, and secondly, mediate plasticity in susceptibility to Cry1Ac, which can account for large differences in LC50 values. Nutrition-Bt interactions such as these have important implications for IRM, particularly given that diet-incorporated Bt bioassays commonly use artificial diets that vary substantially from their self-selected optimal diets, which likely results in underestimates of resistance in the field. Failing to bioassay larvae on ecologically-relevant diets can seriously confound the results of Bt resistance monitoring bioassays and undermine our ability to detect resistance in the field., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Interest in the field of epigenetics has increased rapidly over the last decade, with the term becoming more identifiable in biomedical research, scientific fields outside of the molecular sciences, such as ecology and physiology, and even mainstream culture. It has become increasingly clear, however, that different investigators ascribe different definitions to the term. Some employ epigenetics to explain changes in gene expression, others use it to refer to transgenerational effects and/or inherited expression states. This disagreement on a clear definition has made communication difficult, synthesis of epigenetic research across fields nearly impossible, and has in many ways biased methodologies and interpretations. This article discusses the history behind the multitude of definitions that have been employed since the conception of epigenetics, analyzes the components of these definitions, and offers solutions for clarifying the field and mitigating the problems that have arisen due to these definitional ambiguities., (Copyright © 2015 by the Genetics Society of America.)

Purpose: Existing definitions of clinically important weight loss (WL) in patients with cancer are unclear and heterogeneous and do not consider current trends toward obesity., Methods: Canadian and European patients with cancer (n = 8,160) formed a population-based data set. Body mass index (BMI) and percent WL (%WL) were recorded, and patients were observed prospectively until death. Data were entered into a multivariable analysis controlling for age, sex, cancer site, stage, and performance status. Relationships for BMI and %WL to overall survival were examined to develop a grading system., Results: Mean overall %WL was -9.7% ± 8.4% and BMI was 24.4 ± 5.1 kg/m(2), and both %WL and BMI independently predicted survival (P < .01). Differences in survival were observed across five categories of BMI (< 20.0, 20.0 to 21.9, 22.0 to 24.9, 25.0 to 27.9, and ≥ 28.0 kg/m(2); P < .001) and five categories of %WL (-2.5% to -5.9%, -6.0% to -10.9%, -11.0% to -14.9%, ≥ -15.0%, and weight stable (± 2.4%); P < .001). A 5 × 5 matrix representing the five %WL categories within each of the five BMI categories was graded based on median survival and prognostic significance. Weight-stable patients with BMI ≥ 25.0 kg/m(2) (grade 0) had the longest survival (20.9 months; 95% CI, 17.9 to 23.9 months), and %WL values associated with lowered categories of BMI were related to shorter survival (P < .001), as follows: grade 1, 14.6 months (95% CI, 12.9 to 16.2 months); grade 2, 10.8 months (95% CI, 9.7 to 11.9 months); grade 3, 7.6 months (95% CI, 7.0 to 8.2 months); and grade 4, 4.3 months (95% CI, 4.1 to 4.6 months). Survival discrimination by grade was observed within specific cancers, stages, ages, and performance status and in an independent validation sample (n = 2,963)., Conclusion: A robust grading system incorporating the independent prognostic significance of both BMI and %WL was developed., (© 2014 by American Society of Clinical Oncology.)

Introduction and Aims: Aboriginal Community Controlled Health Services (ACCHSs) are often the primary point of contact for Indigenous Australians experiencing alcohol-related harms. Screening and brief intervention (SBI) is a cost-effective treatment for reducing these harms. Factors influencing evidence-based alcohol SBI delivery in ACCHSs have been identified. Evaluations of strategies targeting these factors are required. The aim of this paper is to quantify the effect of training and tailored outreach support on the delivery of alcohol SBI in four Aboriginal Community Controlled Health Services (ACCHSs)., Design and Methods: A pre- post- assessment of alcohol information recorded in computerised patient information systems of four ACCHSs., Results: For ACCHSs combined there was a statistically significant increase in the proportion of eligible clients with an electronic record of any alcohol information (3.2% to 7.5%, P < 0.0001) and a valid alcohol screen (1.6% to 6.5%, P < 0.0001), and brief intervention (25.75% to 47.7%, P < 0.0001). All four ACCHSs achieved statistically significant increases in the proportion of clients with a complete alcohol screen (10.3%; 7.4%; 2%, P < 0.0001 and 1.3%, P < 0.05), and two in the proportion with a heavy drinking screen (7% and 3.1%, P < 0.0001)., Discussion and Conclusions: Implementing evidence-based alcohol SBI in ACCHSs is likely to require multiple strategies tailored to the characteristics of specific services. Outreach support provided by local drug and alcohol practitioners and a one item heavy drinking screen offer considerable promise for increasing routine alcohol SBI delivery in ACCHSs. Training and outreach support appear to be effective for achieving modest improvements in alcohol SBI delivery in ACCHSs., (© 2012 Australasian Professional Society on Alcohol and other Drugs.)

Introduction: Indigenous Australians experience a disproportionately high burden of alcohol-related harm. Alcohol screening and brief intervention (SBI) offers the potential to reduce this harm if barriers to its delivery in Aboriginal Community Controlled Health Services (ACCHSs) can be optimally targeted., Aims: . Examine health-care practitioners' perceptions of, and practices in, alcohol SBI in ACCHSs., Methods: Semi-structured group interviews with 37 purposively selected health staff across five ACCHSs., Results: Alcohol screening independent of standard health assessments was generally selective. The provision of brief intervention was dependent upon factors related to the patient. Four key factors underlying health-care practitioners' perceptions of alcohol SBI were prominent: outcome expectancy; role congruence; utilisation of clinical systems and processes; and options for alcohol referral. Discussion. The influence of outcome expectancy and role congruence on health-care practitioners' alcohol SBI practices has been identified previously, as has to a lesser extent, their less than optimal use of clinical systems and processes. The influence of options for alcohol referral on health-care practitioners' willingness to deliver alcohol SBI primarily related to their misunderstanding of alcohol SBI and the lack of culturally appropriate alcohol referral options for their patients., Conclusion: An intervention combining interactive, supportive and reinforcing evidence-based dissemination strategies is most likely required to enhance health-care practitioners' knowledge and skills in alcohol SBI delivery, positively orientate them to their role in its delivery, and facilitate integration of evidence-based alcohol SBI into routine clinical processes and locally available systems, (© 2011 Australasian Professional Society on Alcohol and other Drugs.)

Objective: To determine maternal and neonatal outcomes in women with a systemic right ventricle (RV)., Study Design: A retrospective (historical) cohort study of maternal and neonatal outcomes at a tertiary referral academic obstetric unit (Chelsea and Westminster Hospital, London)., Results: Nineteen pregnancies in 14 women with a systemic RV were compared with 76 controls. There were no maternal deaths. In the study group cardiac complications occurred in six (32%) pregnancies. Obstetric complications occurred in four (21%) case pregnancies, not significantly higher than in the control group. The rate of neonatal complication was significantly higher in the study population with neonatal complications in 12 (63%) case pregnancies compared with 13 (17%) control pregnancies. The median birthweight centile was 9 in the study population, significantly lower than the control population., Conclusions: Our cohort study demonstrates high maternal and neonatal morbidity and low birthweight in the presence of a systemic RV. Cardiac complications were more common in women with RV dysfunction and arrhythmias prior to pregnancy. Preconception counselling and tertiary care during pregnancy for these patients is highly advisable., (Copyright © 2011. Published by Elsevier Ireland Ltd.)

Background: Tumors arising from the esophagogastric junction (OGJ) are increasing in incidence in the west, but data from Asian populations are conflicting. Singapore has a mixed-Asian population with an international lifestyle. This study was designed to examine the changing trends in incidence of gastric cardia cancer (type III) within this population and to compare the clinicopathological characteristics and outcome of these tumors with gastric tumors., Methods: Trends in cancer incidence were obtained from the Singapore Cancer Registry. Clinicopathological data were prospectively collected from patients undergoing surgery for gastric cancer who presented to the National University Hospital between 2000 and 2005. Patients underwent surgery with or without (neo)adjuvant therapy. Survival duration was analyzed., Results: The incidence of cardia tumors has increased each decade since 1968 (1968-1982, 6.3%; 1983-1992, 7.6%; 1993-1997, 8.4%; 1998-2002, 9.1%; 2003-2007, 16.2%). Among the study population (n = 159) cardia tumors were associated with male sex (p < 0.01) and dysphagia (p < 0.01). Although R0 resection rates were similar, systemic recurrence rates were higher among patients with cardia cancer (p = 0.031) and survival was reduced compared with patients with non-cardia gastric cancer (median survival 26 vs. 69 months; p < 0.001). Cardia location of the tumor and metastatic lymph node ratio were identified as independent adverse prognostic indicators on multivariate analysis., Conclusions: Similar to western societies, the incidence of proximal gastric cancer is increasing in Singapore. Cardia tumors are associated with poorer outcomes, suggesting that cardia cancer is a distinct disease from true gastric cancer requiring different management strategies to improve the outcome for these patients.

Heparin cofactor II (HCII) is a serine protease inhibitor (serpin) that has been shown to be a predictor of decreased atherosclerosis in the elderly and protective against atherosclerosis in mice. HCII inhibits thrombin in vitro and HCII-thrombin complexes have been detected in human plasma. Moreover, the mechanism of protection against atherosclerosis in mice was determined to be the inhibition of thrombin. Despite this evidence, the presence of HCII in human atherosclerotic tissue has not been reported. In this study, using samples of coronary arteries obtained from the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) study, we explore the local relationship between HCII and (pro)thrombin in atherosclerosis. We found that HCII and (pro)thrombin are co-localized in the lipid-rich necrotic core of atheromas. A significant positive correlation between each protein and the severity of the atherosclerotic lesion was present. These results suggest that HCII is in a position to inhibit thrombin in atherosclerotic lesions where thrombin can exert a proatherogenic inflammatory response. However, these results should be tempered by the additional findings from this, and other studies, that indicate the presence of other plasma proteins (antithrombin, albumin, and alpha(1)-protease inhibitor) in the same localized region of the atheroma.

We report the case of 65-year-old man who developed massive rectal bleeding associated with the use of a fecal collecting device: the Flexi-Seal Fecal Management System. A colonoscopy showed an acute laceration of the anterior rectal wall mucosa, 6 cm from the anal verge, with active bleeding. The tear was most likely the result of an acute event, such as sudden movement of the device within the rectum or trauma sustained during insertion. Massive transfusion was required, and surgical endoscopic treatment was necessary to ensure hemostasis. This is, to our knowledge, the first such case to be reported.

Nursing education in Iran has undergone significant change since its genesis with foreign missionaries over one hundred years ago. More recently, following the 1979 Islamic revolution, nurse education has followed the direction taken by most other countries in moving from an apprenticeship model of training to an academic model. A series of transformative changes to nursing education specifically-and across the higher education system generally-has resulted in nurses now being able to undertake study across all university-based programs up to and including doctoral level. Contemporary nursing students have access to full-text professional journals through the internet, and they may pursue their doctoral studies in other countries. Although these improvements in nursing education in Iran are to be applauded, much more needs to be accomplished to ensure that highly competent nurse practitioners continue to be produced in this country. This article presents an historical overview of the development of nursing education in Iran, within its economic and sociopolitical contexts. Recommendations based upon lessons learned from historical and contemporary realities are presented in order to advance nursing education in this part of world.

Background & Aims: Previous studies of our research group have shown that apoptosis is present in skeletal muscle of tumour-bearing animals subject to cachexia. For this reason we decided to investigate the apoptosis in skeletal muscle of cancer patients., Methods and Results: In the present study, muscle biopsies from weight-losing patients with upper gastro-intestinal cancer showed a significant increase in muscle DNA fragmentation (three-fold), as compared with control subjects. The increase in DNA laddering was associated with an increase in poly(ADP-ribose) polymerase (PARP) cleavage (four-fold) as measured by western blotting. These two events indicate the presence of muscle apoptosis. These changes were associated with a decrease in MyoD protein content, suggesting important alterations in skeletal muscle physiology., Conclusions: The results presented therefore confirm that apoptosis is also present in human subjects undergoing cancer cachexia.

Background: Systemic inflammation has been linked with reduced survival in cancer, however, the role of the host cytokine genotype versus tumour phenotype in the generation of this response is not clearly established. This study examined the relationship between cytokine polymorphisms (IL-1beta 511, IL-6 174, IL-10 1082, TNFalpha 308 and LTalpha +252) and serum cytokine concentrations, serum CRP concentration and survival duration in patients with gastro-oesophageal malignancy., Methods: Two hundred and three newly diagnosed patients with gastric or oesophageal cancer had serum CRP and cytokine concentrations determined by ELISA. SNP genotyping was performed by Taqman allelic discrimination genotyping and compared with the genotype observed in 266 healthy volunteers. Clinico-pathological information was collected prospectively and survival duration was recorded., Results: Distribution of the cytokine genotypes was similar between patients and controls. The IL-6 174 CC and IL-10 1082 GG genotypes were associated with elevated serum CRP (P = .03, P = .01, respectively; Mann-Whitney U test) and sTNF-R (P = .015, P = .02) concentrations. These genotypes were also associated with reduced survival duration (P = .01, P = .047; log-rank test). TNFalpha AA genotype was also associated with reduced survival duration on univariate (P = .032) and multivariate analysis (P = .006, multivariate model), but not with inflammatory markers. No other cytokine polymorphisms were associated with systemic inflammatory markers or prognosis., Conclusions: There is a pro-inflammatory cytokine haplotype (IL-6 CC, IL-10 GG, TNFalpha AA) that is associated with adverse prognosis that may act, at least in part, through an inflammatory mediated mechanism. Determining patients' cytokine haplotype may improve prognostication and allow stratification for intervention studies.

On 26-July, 2005 a mating aggregation of Acropyga epedana Snelling (Hymenoptera: Formicidae) was observed in the Chiricahua Mountains in south-eastern Arizona. This is the first record of a mating flight of A. epedana, the only nearctic member of this pantropical genus. Mating behavior was observed, newly mated queens were collected, and a complete colony was excavated. New information is reported on the natural history and mating behavior of the species. The identity of a mealybug mutualist, Rhizoecus colombiensis (Homoptera: Rhizoecinae) is confirmed. Reproductive females participating in flights all carried mealybugs between their mandibles, indicating a vertical transfer of mealybugs with their ant hosts. No captured foundresses survived long in captivity, most likely due to the death of their mealybugs. The colony excavated had a single queen, though polygyny is common in the genus. Nearly all workers within the nest were heavily parasitized by mites, although males or gynes were not parasitized. These natural history observations are discussed with regard to this poorly understood mutualistic relationship between Acropyga ants and their mealybug partners.

Purpose of Review: Cachexia remains an important cause of morbidity and mortality among cancer patients. The mechanisms underlying this syndrome remain unclear and are almost certainly multifactorial. Evidence from animal models suggests a compelling link between cachexia and inflammation, and a variety of pro-inflammatory cytokines play an integral role. This review summarizes current thinking relating to inflammation, cachexia and prognosis in cancer patients, with particular emphasis on studies relating to recent therapeutic advances., Recent Findings: Pro-inflammatory cytokines induce the acute phase protein response, a key marker of systemic inflammation. Recent evidence has also implicated other tumour-derived mediators, such as proteolysis-inducing factor and parathyroid hormone-related peptide. In addition, systemic inflammation has been found in association with many malignancies, and has been correlated with weight loss, hypermetabolism, anorexia, and adverse prognosis. Treatments such as fish oil, monoclonal antibodies, and non-steroidal anti-inflammatory drugs, have all been utilized to attenuate systemic inflammation and influence weight loss. Recent clinical studies have suggested that eicosapentaenoic acid and cyclo-oxygenase 2 inhibitors promote weight gain and downregulate the acute phase protein response., Summary: Pro-inflammatory processes are clearly implicated in the hypermetabolism and weight loss associated with cancer-associated cachexia. In addition, the presence of systemic inflammation is now clearly linked with adverse prognosis in patients with cancer, which cannot be fully explained by the association with weight loss. Systemic inflammation remains an important area for novel therapeutic targets in combating cachexia, and eicosapentaenoic acid and cyclo-oxygenase 2 inhibitors appear to be efficacious in the armory against cachexia.

Background: Parathyroid hormone-related peptide (PTHrP) is a tumor-derived circulating factor that has been associated with hypercalcemia of malignancy. The role of PTHrP as a prognostic indicator remains unclear. Studies suggest that it may function as a growth factor; and, recently, the ability of PTHrP to induce cytokine expression has been described. PTHrP also has been proposed as a procachectic factor. In this study, the authors investigated the prognostic value of PTHrP in patients who had gastroesophageal carcinoma without hypercalcemia and determined whether PTHrP was associated with systemic inflammation and adverse nutritional status., Methods: Patients were recruited at the time of diagnosis. Serum was collected for determination of c-terminal fragment PTHrP (cPTHrP) levels (by radioimmunoassay) and calcium levels as well as levels of serum cytokines and acute-phase proteins (with an enzyme-linked immunosorbent assay). Nutritional assessment of patients was undertaken at the same time as serum collection. Patients underwent routine staging, and survival duration was recorded., Results: One hundred fifty-one patients with esophagogastric carcinoma were recruited. Six of 151 patients (4.0%) patients were hypercalcemic, and 26 patients (17.2%) had elevated serum cPTHrP levels. There was no association between the cPTHrP level and either serum calcium concentrations (P = 0.72) or adverse nutritional status. Elevated cPTHrP, however, was associated with significantly higher serum levels of soluble tumor necrosis factor receptor (P = 0.008) and with significantly lower levels of transferrin (P = 0.009) and albumin (P = 0.02). There was also a weak association with C-related protein levels (P = 0.06). Elevated cPTHrP levels also were associated with an adverse prognosis, as determined by reduced survival duration, on univariate analysis (P = 0.038), but not on multivariate analysis (P = 0.15)., Conclusions: Elevated serum cPTHrP levels were present in approximately 17% of patients with gastroesophageal carcinoma in the absence of hypercalcemia and was associated with markers of systemic inflammation and with an adverse prognosis., ((c) 2005 American Cancer Society.)

This Australian study identified and described the incidence of medication errors among registered nurses, the type and causes of these errors and the impact that administration of medications has on the professional practice of registered nurses. Mostly, medication errors were attributed to documentation issues, including: illegible handwriting, misunderstanding abbreviations, misplaced decimal point, misreading and misinterpreting written orders. Several human factors were attributed to potential causes of medication errors, including: stress, fatigue, knowledge and skill deficits. Environmental factors, namely, interruptions and distractions during the administration of medications, were also attributed to potential errors. The study found professional nursing practice involving administration of medications had a strong education, patient and ethical focus. Over a quarter of the respondents indicated that further training in medication administration would positively impact on their nursing practice. The registered nurses also highlighted they would appreciate more time to spend with patients when administering medications. Medication errors are not the sole responsibility of any single professional group, therefore, collaboration with other health professionals is central to establishing processes, policies, strategies and systems that will reduce their occurrence. The organisation and those nurses employed within it share an accountability to ensure safe administration of medications to patients. Based on study results, several recommendations are directed towards preventing or reducing medication errors and supporting nurses in providing best practice.

In England, the education of nurses in the academic arena has a relatively short history arguably representing recent advancement of the nursing discipline. Until we undertook this study, however, expectations for the next decade were unknown. The current investigation replicates a similar study of Australian nurse academics (Sellers & Deans, 1996) which found discrepancies between how nurse academics perceived the future development of the profession, compared to how they actually expected it to develop. In order to provide information concerning the future of nursing education in England and related professional and social factors, a random sample of nurse academics was surveyed. Findings indicate that although advances have been made, there are a number of concerns regarding the development of nursing as a discipline. These include parity of status with other academic areas, resource issues, the workload of nurse academics and the perception that there is lack of cohesiveness amongst nurses as a professional group. Findings in this study closely mirror results in the Australian study indicating similarities in how the nursing profession copes with the transition from a predominantly hospital based education program to a program grounded in academic institutions.

In Australia, the education of nurses in the academic arena now has a decade of history which arguably represents advancement of the nursing discipline. Until the conduct of the study which is the subject of this report, however, expectations for the next decade were unknown. In order to provide information concerning the future of nursing education and related professional and social factors, and entire population of nurse academics in Australia was surveyed. Findings indicate that although advances have been made, there are a number of concerns regarding the rate of disciplinary development. These include parity of status with other academic areas, resource issues, the workload of nurse academics and the perception that there is lack of cohesiveness amongst nurses as a professional group.

1. The major constraints preventing psychiatric nurses from conducting research are lack of time and knowledge. 2. Nurses can be motivated to explore the possibility of conducting research without having necessary skills or knowledge to start. 3. The nursing profession must face its responsibility to support and nurture nurses' interests in conducting and using research.

1. An essential characteristic for nurses is hope, which much be passed on to caregivers of people diagnosed with schizophrenia. 2. The sharing of experiences by families contributes to the development of a common human bond that facilitates understanding and acceptance of mental illness by significant others. 3. Empowerment of family caregivers increases their ability to deal with the illness and enhances the family's chance of living a normal life.

A brief mental fatigue questionnaire was administered to normal subjects and muscle-diseased, Chronic Fatigue Syndrome (CFS), recovered CFS and depressed patients. The questionnaire was found to have excellent internal consistency and discriminated effectively between CFS and depressed patients on the one hand and recovered CFS, normal and muscle-diseased patients on the other. However, the scale failed to discriminate between CFS and depressed subjects, who were found to experience qualitatively and quantitatively similar mental fatigue symptoms.

Macrobenthic animal communities that colonized sand-filled aquaria were exposed to 1,2,4-trichlorobenzene (TCB), a recent replacement for polycholorinated biphenyls in the electrical industry. In one test, communities established by planktonic larvae entrained in continuously supplied unfiltered seawater for 50 days were exposed to waterborne TCB for 6 days; in the second test, the toxicant was added to the sediment before 8 weeks of colonization. Concentrations that affected community structure were usually two orders of magnitude lower for waterborne TCB than for sediment-bound TCB, but the same types of organisms were affected by each route of exposure. The lowest TCB concentrations (measured) that affected average numbers of individuals exposed via the water were 0.04 mg/liter for mollusks, 0.4 mg/liter for arthropods, and 4 mg/liter for annelids. Average number of species was significantly lower than the control at 4 mg/liter. For TCB exposures via the sediment, the lowest concentrations (nominal) that affected average numbers of individuals were 100 micrograms/g for mollusks and echinoderms, and 1000 micrograms/g for arthropods and annelids. Average number of species in experimental aquaria was significantly lower than the control at greater than or equal to 100 micrograms/g. TCB persisted in sediments, but some leached into water throughout the 8-week exposure via sediment.

The actions of NAN-190, a putative 5-HT1A antagonist, were assessed in rats. The selective 5-HT1A agent ipsapirone suppressed operant responding, but this effect was not antagonised by NAN-190, which suppressed responding itself in a dose-related manner, and had additive effects when administered with ipsapirone. These data do not support suggestions that NAN-190 is a 5-HT1A antagonist. NAN-190 may be a 5-HT1A partial agonist which can antagonise effects of full 5-HT1A agonists.

Effects of water-bourne toxicants on regeneration of arms by the brittle star, Ophioderma brevispina, are described. Regeneration was inhibited by 0.1 micrograms liter-1 bis(tri-n-butyltin)oxide and bis(triphenyltin)oxide. Both substances are known to act upon the nervous system, and it is suggested that inhibition was caused by neurotoxicological action of the tin compounds or by their direct effect upon tissue at the breakage point. The former is most likely because regeneration is mediated by the radial nerves of brittle stars.