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The mechanisms responsible for sediment resuspension and transport by nonlinear internal waves (NLIWs) remain poorly understood largely due to a dearth of detailed field measurements. We present novel observations of the turbulent benthic boundary‐layer (BBL) beneath trains of NLIWs of depression in the ocean. At the 250 m deep, low‐gradient (<0.2%) continental shelf site the BBL was near well mixed to an average height of about 10 m above the bottom. Above this bottom mixing‐layer, stratification constrained the extent of vertical sediment transport. NLIWs drove sediment transport by a combination of bed‐stress intensification, turbulent transport, and a vertical pumping mechanism associated with the compression and subsequent expansion of the mixing‐layer. There was no evidence that the observed dynamics were associated with a global instability, as proposed in previous studies. The results have implications for cross‐shelf mass transport and highlight future challenges for measuring and modeling boundary‐layer processes within shelf seas. Plain Language Summary: With wave heights reaching 100 m, nonlinear internal waves generate some of the strongest ocean currents on the world's continental shelves. These extreme currents penetrate down to the seabed, where they greatly enhance sediment resuspension, eject sediments high into the water column, and generate some of the strongest forces on subsea engineered structures. These waves likely redistribute settled biological material, dense plastics, and sediment‐sorbed hydrocarbons on the continental shelf. Despite their significance, the details of these processes remain inadequately understood, owing to the challenges of detailed near‐bed observation and equally the challenges of configuring laboratory and computational experiments to be representative of ocean conditions. We present new detailed near‐bed observations under 70 m nonlinear internal waves in the ocean. The observations (1) show how these waves enhanced resuspension and transport of sediments; (2) identify a potential pathway for transport of terrestrial material from the continent toward the abyss; and (3) highlight some future challenges for modeling these processes in computer simulations of the ocean. Key Points: Novel observations of the oceanic benthic boundary‐layer structure provide unique insight into sediment transport under NLIWs of depressionSediment transport is explained by strong turbulence and pumping by the NLIW without recourse to complex instability mechanismsThe findings have implications for cross‐shelf transport, RANS ocean modeling, and DNS/LES modeling of NLIWs in the ocean [ABSTRACT FROM AUTHOR]

Non‐linear internal waves (NLIW) are important to processes such as heat transfer, nutrient replenishment and sediment transport on continental shelves. Our unique field observations of shoaling NLIW of elevation revealed a variety of different wave shapes, varying from relatively symmetric waves, to waves with either steepened leading‐ or trailing‐faces; many had evidence of trapped cores. The wave shape was related to the position of maximum density overturns and diapycnal mixing. We observed both shear (where sheared currents overcome the stabilizing effects of stratification) and convective (where the local velocity exceeds the wave propagation speed) instabilities. The elevated diapycnal mixing (>10−3 m2s−1) and heat flux (>500 Wm−2) were predominantly local to the NLIW of elevation packets, and were transported onshore 10s kilometers with the wave packets. We demonstrate that wave steepness may be a useful bulk property for the parameterization of wave‐averaged diapycnal heat flux. Plain Language Summary: Predicting the distribution of constituents such as nutrients, heat, sediment and pollutants on the continental shelf is key to processes such as: the safe operation of offshore infrastructure; understanding the variation in primary productivity; the prediction of marine heat waves; and environmental impact assessments of new activities. Non‐linear internal waves, waves that travel within the stratified water column, are likely to have a significant impact on constituent transport; however, they are poorly understood. Here we present unique observations that quantify the properties of a class of these nonlinear internal waves, known as waves of elevation. These waves can break in a similar way to surface waves at the beach, leading to dramatic increases in turbulent mixing over horizontal length scales of 10s kilometers. We have used our observations to define the amount of vertical heat transport induced by the breaking waves as a function of wave steepness. The vertical heat transport can be used as a proxy to estimate the vertical nutrient transport. This study has made a step change in quantifying the impact of NLIW of elevation on vertical transport. Key Points: Nonlinear internal waves of elevation can form both convective and shear instabilities, resulting in enhanced diapycnal mixing and heat fluxBreaking continues as the nonlinear waves propagate onshore, influencing diapycnal mixing and vertical heat flux over 10s of kilometersThe elevated heat flux associated with the nonlinear internal waves of elevation increases with the wave steepness [ABSTRACT FROM AUTHOR]

Background Recently, the UK Armed Forces have revised the ground close combat role to include women. Aims To assess the potential mental health impact of this initiative we examined gender differences in deployment patterns, work strain, occupational factors, mental health, alcohol use and help-seeking following operational deployment. Methods The study was a secondary analysis of self-report survey data; 8799 men (88%) and 1185 women (12%) provided data. A sub-sample (47%, n = 4659) provided data concerning post-deployment help-seeking. The latter consisted of 408 women (8.8%) and 4251 men (91%). Results With the exception of alcohol misuse, which was significantly lower for women, women reported significantly more common mental disorder symptoms, subjective depression and self-harm. Women were significantly more likely to seek help from healthcare providers. Men were significantly more likely to have deployed operationally and for longer cumulative periods. Subjective work strain, but not job control, was significantly lower for women whose military careers were significantly shorter. Post-traumatic stress disorder (PTSD) symptom intensity was similar to men. Conclusions With the exception of PTSD and alcohol misuse, UK military women experience more mental health-related problems than military men. This finding was not related to the more arduous aspects of military service as women served for shorter times, deployed less and for shorter cumulative periods and were less likely to report work-related stress. [ABSTRACT FROM AUTHOR]

Background Internationally, women are about to undertake combat duties alongside their male colleagues. The psychological effect of this policy change is largely unknown. Aims To explore the mental health impact of combat exposure among military women. Methods Self-report, between-subjects survey data were collected in Iraq and Afghanistan on four occasions between 2009 and 2014 (n = 4139). Differences in mental health, stigmatization, deployment experiences, intimate relationship impact, perception of family support levels, unit cohesion, leadership and help-seeking were compared between deployed men and women. Comparisons were repeated with the study sample stratified by level of combat exposure. Outcomes were examined using logistic regression adjusted for socio-demographic, mental health and military factors. Results Overall, 4.1% of women and 4.3% of men reported post-traumatic stress disorder (PTSD) (odds ratio (OR) 1.31, 95% confidence interval (95% CI) 0.70–2.46); 22% of women and 16% of men reported symptoms of common mental disorder (CMD) (OR 1.52, 95% CI 1.11–2.08). Women were less likely to report mental health-related stigmatization (OR 0.68, 95% CI 0.53–0.87), negative relationship impact from deployment (OR 0.69, 95% CI 0.49–0.98) and subjective unit cohesion (OR 0.69, 95% CI 0.53–0.90). Help-seeking for emotional problems was similar by gender (OR 1.22, 95% CI 0.84–1.77). Overall, outcomes were minimally impacted by level of combat exposure. Conclusions Although women experienced more CMD symptoms, PTSD symptoms were similar by gender. Subject to confirmation of the study findings, women may not require enhanced mental healthcare during deployment for exposure-based conditions such as PTSD when undertaking the ground close combat role. [ABSTRACT FROM AUTHOR]

The subfamilies, genera, and most frequently encountered species of North American Calliphoridae are reviewed, including a comprehensive pictorial key to the forensically important blow flies of North America. Distribution maps are provided for all species. [ABSTRACT FROM AUTHOR]

We describe a framework for the simultaneous estimation of model parameters in a partial differential equation using sparse observations. Markov Chain Monte Carlo sampling is used in a Bayesian framework to estimate posterior probability distributions for each parameter. We describe the necessary components of this approach and its broad potential for application in models of unsteady processes. The framework is applied to three case studies, of increasing complexity, from the field of cohesive sediment transport. We demonstrate that the framework can be used to recover posterior distributions for all parameters of interest and the results agree well with independent estimates (where available). We also demonstrate how the framework can be used to compare different model parameterizations and provide information on the covariance between model parameters. Plain Language Summary: We describe a framework for the simultaneous estimation of multiple unobserved parameters by combining observations of a tracer with a numerical model. This framework uses Bayesian inference techniques established in statistical literature to estimate the unobserved parameters of interest used in the model with uncertainty quantification. We explain the key components of this framework in simple terms to encourage its use for analyzing other unsteady processes and performing quantitative inference on parameters that are difficult or impossible to measure directly. We then demonstrate the framework's efficacy by applying it to three case studies from the field of cohesive sediment transport that all use the transport equation (advection‐diffusion). Inferred parameter values show good agreement with independent estimates, where available. Key Points: Probabilistic framework to estimate unobserved erosion model parameters using sparse measurements collected above the seabedGeneral approach can be updated with any model parameterization and quantitatively comparedThe framework is applicable to many similar data sets with both unsteady or quasi‐steady forcing and response [ABSTRACT FROM AUTHOR]

Vocal cord palsy (VCP) is a major complication of thyroidectomy. Some patients have preexisting VCP prompting the need for routine or selective preoperative evaluation of the vocal cords. The study aims at ascertaining the prevalence of preoperative VCP and making appropriate recommendations. This is a retrospective study of all adult patients who had thyroidectomy at the University of Nigeria Teaching Hospital. Case notes of patients who had thyroidectomy at the hospital from July 2010 to June 2015 were retrieved. Variables studied included biodata, duration of goiter, preoperative hoarseness, outcome of indirect laryngoscopy (IDL), histology of specimen, duration of follow-up, and incidence of postoperative hoarseness. Descriptive statistical analysis was done using SPSS version 20. Of the 91 patients aged 21-70 years (mean 42.08 years, SD 15.40), females outnumbered males with a M:F ratio of 1:10.4. Five patients had preoperative hoarseness, but only three had VCP. IDL was done for 25 (27.4%) patients out of which 22 (88.0%) had normal studies while the remaining three (all from the five with hoarseness) had VCP. Histology of the specimens showed malignancy in 10 (11%), benign in 55 (60.4%), and no report in 26 (28.6%). Five of the malignant histology patients showed normal findings on IDL, three had VCP and two had no preoperative IDL. There was no case of asymptomatic VCP. Vocal cord evaluation is recommended for patients with voice symptoms and those with malignant goiter. [ABSTRACT FROM AUTHOR]

Background: Most studies of the psychological impact of military deployment focus on the negative and traumatic aspects. Less is known about the full range of deployment experiences nor how these may impact on career intentions. Aims: To examine subjective operational experiences and career intentions in deployed UK military personnel using data gathered toward the end of an operational deployment. Methods: Data were gathered during deployment in Iraq and Afghanistan. A self-report survey collected data on sociodemographic, operational and military factors. Respondents provided their strength of agreement or disagreement with six potentially positive deployment experiences and their endorsement or rejection of six possible career intentions. Two mental health measures assessed symptoms of common mental disorder and post-traumatic stress disorder. Results: Responses were 681 in Iran 2009 (100% response rate); 1421 in Afghanistan in 2010 (100%), 1362 in 2011 (96%) and 860 in 2015 (91%). Five of the potentially positive outcomes were endorsed by >50% of the sample: confidence about remaining healthy after returning home, pride in accomplishments, increased confidence in abilities, improved unit cohesion and experiencing a positive life effect. Ninety per cent of respondents planned to continue in service after returning home. Fewer positive deployment experiences, poorer mental health, lesser unit cohesion and more negative impressions of leadership were significantly associated with intention to leave service. Conclusions: Contrary to the popular belief that UK military personnel deployed to Iraq or Afghanistan experience negative outcomes, this paper shows that deployment can be a positive experience for a substantial majority of deployed personnel. [ABSTRACT FROM AUTHOR]

Background This service evaluation explored personnel's preparedness for deploying on the UK's military response to the Ebola crisis in West Africa. Aims To capture the views of medical and support personnel in relation to the pre-deployment training they received for that mission. Methods Two separate groups nominated to attend pre-deployment training completed a survey on the first and last day of their course. Participants were asked to subjectively rate the quality of training and identity aspects of their preparation they found particularly positive, those that generated concerns and to suggest future improvements. Results Subjective ratings of preparedness for all aspects of the mission significantly improved by the last day of training among both groups of trainees (P < 0.001). Thematic analysis of qualitative data established that unit support and practical aspects of training were positively received. For group 1, a prevalent concern on the first and last day of training was a fear of the unknown. Group 2 respondents were concerned about the quality of information and its transmission and the time available to prepare. Respondents in both groups reported the need for consistent and timely information and for the training to be refined for those undertaking a non-clinical role. Conclusions The collective training package was highly effective in preparing personnel to feel more confident and competent to undertake the medical mission in West Africa. [ABSTRACT FROM AUTHOR]

Objectives: Ectopic pregnancy (EP) is a major high‐risk outcome following a pregnancy of unknown location (PUL) classification. Biochemical markers are used to triage PUL as high vs low risk to guide appropriate follow‐up. The M6 model is currently the best risk‐prediction model. We aimed to update the M6 model and evaluate whether performance can be improved by including clinical factors. Methods: This prospective cohort study recruited consecutive PUL between January 2015 and January 2017 at eight units (Phase 1), with two centers continuing recruitment between January 2017 and March 2021 (Phase 2). Serum samples were collected routinely and sent for β‐human chorionic gonadotropin (β‐hCG) and progesterone measurement. Clinical factors recorded were maternal age, pain score, bleeding score and history of EP. Based on transvaginal ultrasonography and/or biochemical confirmation during follow‐up, PUL were classified subsequently as failed PUL (FPUL), intrauterine pregnancy (IUP) or EP (including persistent PUL (PPUL)). The M6 models with (M6P) and without (M6NP) progesterone were refitted and extended with clinical factors. Model validation was performed using internal–external cross‐validation (IECV) (Phase 1) and temporal external validation (EV) (Phase 2). Missing values were handled using multiple imputation. Results: Overall, 5473 PUL were recruited over both phases. A total of 709 PUL were excluded because maternal age was < 16 years or initial β‐hCG was ≤ 25 IU/L, leaving 4764 (87%) PUL for analysis (2894 in Phase 1 and 1870 in Phase 2). For the refitted M6P model, the area under the receiver‐operating‐characteristics curve (AUC) for EP/PPUL vs IUP/FPUL was 0.89 for IECV and 0.84–0.88 for EV, with respective sensitivities of 94% and 92–93%. For the refitted M6NP model, the AUCs were 0.85 for IECV and 0.82–0.86 for EV, with respective sensitivities of 92% and 93–94%. Calibration performance was good overall, but with heterogeneity between centers. Net Benefit confirmed clinical utility. The change in AUC when M6P was extended to include maternal age, bleeding score and history of EP was between −0.02 and 0.01, depending on center and phase. The corresponding change in AUC when M6NP was extended was between −0.01 and 0.03. At the 5% threshold to define high risk of EP/PPUL, extending M6P altered sensitivity by −0.02 to −0.01, specificity by 0.03 to 0.04 and Net Benefit by −0.005 to 0.006. Extending M6NP altered sensitivity by −0.03 to −0.01, specificity by 0.05 to 0.07 and Net Benefit by −0.005 to 0.006. Conclusions: The updated M6 model offers accurate diagnostic performance, with excellent sensitivity for EP. Adding clinical factors to the model improved performance in some centers, especially when progesterone levels were not suitable or unavailable. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

The article focuses on physiology, testing and disorders of platelet function. Topics discussed include production of thrombopoietin (TPO) in liver and kidneys which play a significant factor in proliferation, differentiation and maturation of megakaryocytes; treatment of quantitative platelet disorders by options like platelet transfusion and immunosuppression with steroids; and use of antiplatelet agents resulting in acquired platelet disorders.

Background: Obesity is more prevalent in adults with intellectual disabilities (ID) compared to the general population. Motivations for weight loss may influence engagement with weight management programmes and have only been studied in adults without ID. Aims: To determine reasons given by adults with ID and obesity for seeking weight loss and whether these reasons differ from those of their carers. Methods: Prior to a multi-component weight management intervention, participants were asked "why do you want to lose weight?" Carers were asked their views and these were compared to the answers given by the adult with ID. Responses were themed. The Fisher's Exact analysis was used to test for any relationship between reasons for seeking weight loss and participants' level of ID, age, gender and BMI. Results: Eighteen men and 32 women; age 41.6 SD 14.6 years; BMI 40.8 SD 7.5 kg/m2; Level ID Mild (28 %), Moderate (42 %), Severe (22 %), Profound (8 %). Eleven were unable to respond. Six themes emerged; Health; Fitness / Activity / Mobility; Appearance / Clothes; Emotional / Happiness; For Others; Miscellaneous. The most frequent reason given overall and by women was "appearance." Carers cited "health" most frequently and "appearance" least, rarely agreeing with participants. "Health" was given as a reason more from older adults and those with milder ID. No statistically significant associations were found between reasons for seeking weight loss and BMI age, gender or level of ID but the differing views of adults with ID and their carers were clear. Conclusions: Views of adults with obesity and mild or moderate ID can be collected. The opposing views of adults and their carers may affect motivation for weight loss. [ABSTRACT FROM AUTHOR]

Leucocytes respond rapidly to pathogenic and other insults, with responses ranging from cytokine production to migration and phagocytosis. These are bioenergetically expensive, and increased glycolytic flux provides adenosine triphosphate (ATP) rapidly to support these essential functions. However, much of this work is from animal studies. To understand more clearly the relative role of glycolysis and oxidative phosphorylation in human leucocytes, especially their utility in a translational research setting, we undertook a study of human peripheral blood mononuclear cells (MNCs) bioenergetics. Glycolysis was essential during lipopolysaccharide (LPS)-mediated interleukin (IL)−1β, IL-6 and tumour necrosis factor (TNF)-α production, as 2-deoxy-D-glucose decreased significantly the output of all three cytokines. After optimizing cell numbers and the concentrations of all activators and inhibitors, oxidative phosphorylation and glycolysis profiles of fresh and cryopreserved/resuscitated MNCs were determined to explore the utility of MNCs for determining the bioenergetics health profile in multiple clinical settings. While the LPS-induced cytokine response did not differ significantly between fresh and resuscitated cells from the same donors, cryopreservation/resuscitation significantly affected mainly some measures of oxidative phosphorylation, but also glycolysis. Bioenergetics analysis of human MNCs provides a quick, effective means to measure the bioenergetics health index of many individuals, but cryopreserved cells are not suitable for such an analysis. The translational utility of this approach was tested by comparing MNCs of pregnant and non-pregnant women to reveal increased bioenergetics health index with pregnancy but significantly reduced basal glycolysis and glycolytic capacity. More detailed analysis of discrete leucocyte populations would be required to understand the relative roles of glycolysis and oxidative phosphorylation during inflammation and other immune responses. [ABSTRACT FROM AUTHOR]

Background: Nasal hematoma/abscess is an uncommon entity, but capable of leading to serious consequences if not handled meticulously, and with urgency. Objective: To present the management, and outcome of nasal septal hematoma/abscess in a Nigerian tertiary institution. Method: Consecutive patients diagnosed with nasal septal hematoma/abscess over a 10-year period, treated at the University of Nigeria Teaching Hospital, Enugu, Nigeria, were prospectively studied. The processes leading to diagnosis, treatment, and outcome were sequentially evaluated. Results: Fifty-three patients (37 males and 16 females), age 5-65 years (with mean age of 23.10 years), were included. Surgical drainage of the hematoma/abscess, intranasal packing with insertion of drain was performed with total resolution of problem in all the cases. Conclusion: Incision and drainage, and intranasal packing with insertion of drain was effective in treating nasal septal hematoma/abscess. [ABSTRACT FROM AUTHOR]

Background Trauma Risk Management (TRiM) is a peer support system developed within the British Armed Forces. It aims to ensure that trauma-exposed personnel are properly supported and encouraged to seek timely help should they develop mental health problems that fail to resolve spontaneously. Aims To summarize current knowledge about TRiM and make recommendations for further research. Methods A search of PsychINFO, CINAHL and PubMed identified 13 published papers. Results TRiM outcomes were represented in different ways within the relevant studies suggesting that TRiM may have effects additional to those that it seeks to achieve. For example, a randomized controlled trial demonstrated that TRiM had a specific positive occupational effect and did no harm; a qualitative study suggested that TRiM enhanced liaison between mental health workers and line managers and a service evaluation suggested that it reduced sickness absence. In general, the process appears to enhance trauma-exposed personnel's reliance on peer support and TRiM was reportedly acceptable and sustainable. Conclusions Evidence suggests that TRiM's utility has moved beyond the military to other organizations where personnel risk occupational traumatic exposure. Further research would help to understand how TRiM is perceived by line managers and how it functions within the trauma-prone populations. [ABSTRACT FROM AUTHOR]

Background Recent epidemiological evidence suggests that military personnel commonly remain psychologically resilient in the face of adversity they face on deployment. However, the processes that promote resilience have not been well assessed within the UK military. For many years, the UK Armed Forces have operated a policy of rest and recuperation (R&R), which refers to the brief period during which troops return home when on an operational tour of duty. While R&R is thought to play an import ant role in promoting recovery and well-being, there is as yet no empirical evidence to support its effectiveness. Aims To explore whether R&R promotes well-being and recovery from the strains of deployment in military personnel. Methods Participants completed self-report measures of mental health and exposure to potentially traumatic events (PTEs), as well as an R&R Recovery Questionnaire (R&RRQ). Results Statistical analysis indicated that the R&RRQ was a reliable measure within the sample of 97 subjects. Participants who reported recovery following R&R reported fewer symptoms of mental health difficulties. However, increased deployment exposure to PTEs was associated with feeling less recovered at the end of R&R. Conclusions These preliminary data suggest that R&R can be useful for troops if they can use the time to recover. This study’s results are relevant to policymakers and leaders in the military and other groups placed in challenging environments but more work is needed to understand how R&R works and to maximize its capacity to promote well-being among military personnel. [ABSTRACT FROM AUTHOR]

The extent to which configurational entropy can stabilise a single solid solution in an Al0.5CrFeCoNiCu high entropy alloy has been assessed through characteristion of samples following casting and heat treatment at 1000 °C. At temperatures between 1000 °C and the onset of melting, the alloy was shown to be within a two phase field and these phases were stable following prolonged exposure at elevated temperature. X-ray and transmission electron diffraction indicated that both constituent phases had an fcc structure. Therefore, these phases share a Gibbs energy curve that must contain two local minima at the solidus temperature, rather than the single minimum required for a continuous solid solution. These observations indicate that there is no temperature at which this material is in a stable, solid state single phase field and that therefore, the configurational complexity is insufficient to stabilise a solid solution phase against enthalpic effects. [ABSTRACT FROM AUTHOR]

Background A major incident involving multiple fatalities occurred in Cumbria, England on 2 June 2010. The Cumbrian Constabulary deployed an organizational peer support response for personnel involved known as trauma risk management (TRiM). Aims To examine data routinely gathered during the TRiM process to evaluate the relationship of the intervention to sickness absence. Methods Using incident databases, details were gathered regarding exposure to the murders and type of TRiM intervention, including an assessment of the psychological risk to the individual of developing a trauma-related mental health problem. Sociodemographic information was collated by the occupational health department. Cumulative sickness absence data in the 2 months following the murders were used as a proxy for mental health status. Results A total of 717 police officers and civilian support staff were identified. High levels of traumatic exposure were associated with subsequent receipt of a TRiM intervention. The majority of psychological risk indices reduced between the initial and subsequent evaluation. Greater traumatic exposure was associated with longer sickness absence lengths. Engagement in the TRiM process was associated with a reduction in sickness absence especially in more junior ranks. Conclusions In this study, we found that TRiM deployed within a police force responding to a major event offered a way of structuring a response for those involved. Our data suggest that TRiM may offer a way of assessing psychological risk so that officers can be offered early supportive interventions. Our data suggest that TRiM may help to ameliorate some of the negative effects of high trauma exposure. [ABSTRACT FROM PUBLISHER]

The article focuses on the implication of anaemia in preoperative patients. It states that preoperative anaemia has an adverse effect upon functional recovery, length of hospital stay, and quality of life. It presents different compensatory mechanisms stimulated in order to restore the supply of oxygen to the tissues, in response to anaemia. Widespread approval of a structured approach to detection, evaluation, and management is recommended.

Background Recently, proposals have been made to improve mental health care for UK military veterans. Combat Stress (CS), a veteran’s charity, has provided mental health services for veterans since 1919. Since 2003, service users have included veterans from the Iraq and Afghanistan conflicts; however, their pattern of help-seeking has not been evaluated. Aims To describe the characteristics of the veteran population of the recent Iraq or Afghanistan conflicts who sought help from CS between 2003 and May 2011. Methods CS Iraq and Afghanistan veteran clinical and welfare records were evaluated. Results Nine hundred and eighty-eight records were evaluated. The median time for veterans of recent conflicts to seek help from CS since discharge from military service was ~2 years, considerably shorter than the mean time of 14 years previously estimated by CS. Approximately, three-quarters of the veterans receiving a full clinical assessment (n = 114), received a diagnosis of post traumatic stress disorder (PTSD) (n = 87). Approximately half of the clinically assessed veterans self-referred to CS (51%); their most frequent diagnosis was PTSD. Conclusions Veterans who have served in Iraq and Afghanistan are presenting to Combat Stress sooner, and at a younger age, than veterans of previous conflicts and operations. [ABSTRACT FROM AUTHOR]

We consider dynamical decoupling schemes in which the qubit is continuously manipulated by a control field at all times. Building on the theory of the Uhrig dynamical decoupling (UDD) sequence and its connections to Chebyshev polynomials, we derive a method of always-on control by expressing the UDD control field as a Fourier series. We then truncate this series and numerically optimize the series coefficients for decoupling, constructing the Chebyshev and Fourier expansion sequence. This approach generates a bounded, continuous control field. We simulate the decoupling effectiveness of our sequence versus a continuous version of UDD for a qubit coupled to fullyquantum and semi-classical dephasing baths and find comparable performance. We derive filter functions for continuous-control decoupling sequences, and we assess how robust such sequences are to noise on control fields. The methods we employ provide a variety of tools to analyze continuous-control dynamical decoupling sequences. [ABSTRACT FROM AUTHOR]

Abstract: Managing Protected Areas (PAs) is a challenging task, and globally many instruments have been utilised for this purpose. Existing research demonstrates that the effectiveness of these instruments is highly dependent on their social acceptability among local communities resident within PAs. Consequently, investigating local attitudes and perceptions of Protected Area (PA) policies has been emphasised in recent studies. Drawing on empirical work conducted in two National Parks including river delta ecosystems designated as Ramsar wetlands in northern Greece, this paper examines local residents'' perceptions of three hypothesized policy options (regulatory, market-based and participatory) for Park management. The influence of social capital elements (social trust, institutional trust and social networks) on residents'' perceptions is explored. The findings reveal a high degree of importance attached by resident communities to Park designation in both PAs, though residents'' perceptions of the proposed management options varied. The regulatory option was regarded as the least restrictive, while the most restrictive was perceived to be the market-based option. However, greater benefits were identified by residents from the market-based option, while the fewest benefits were considered to arise from the proposed regulatory option. Furthermore, local residents'' perceptions were significantly shaped by the proposed management and decision-making structure offered under each policy option. The influence of different social capital elements on residents'' perceptions also varied in the study sample, with social trust and institutional trust positively correlated with the benefits that were perceived to arise from the different policy options. Moreover, when social capital was measured as an aggregate indicator at the level of the individual, it was positively correlated with perceived environmental benefits. [Copyright &y& Elsevier]

Background Third location decompression (TLD) refers to the initial process, undertaken by military personnel at the end of an operational deployment, whereby adjustment from military operations commences. TLD has been shown to be useful for personnel in formed units (FU). Aims To examine the subjective utility of TLD for personnel deployed as individual augmentees (IAs) by comparing their experience with FU personnel. Methods One hundred and twenty-nine IAs and 121 FU personnel completed a short survey at the end of the decompression period asking about operational exposures, perceived usefulness, stigma, concerns about readjustment and post-traumatic stress symptoms (PTSS). Results The strongest predictor of perceived utility was the desire to participate prior to arrival at the facility. FU personnel were more likely to want to participate in TLD than IAs (60% versus 30%); however, on completion, IAs reported high usefulness ratings with 78% of IAs and 84% of FU personnel finding it useful or a little useful. More FU personnel reported substantial PTSS, reporting that high numbers of PTSS were associated with finding the briefings that dealt with traumatic stress useful. Personnel reporting substantial operational exposures also reported greater levels of PTSS. Conclusions IAs found TLD to be as useful as FU personnel; therefore, exclusion from the TLD process is not warranted. Military commanders should consider restricting TLD to both IA and FU personnel deemed to be at increased risk of a difficult adjustment due to greater operational exposure. Our data suggest that smaller numbers of IA personnel would fall into this group. [ABSTRACT FROM PUBLISHER]

Abstract: This article derives bending moment–axial force (M–P) interaction curves for mild steel by considering elastic–plastic and strain hardening idealisations with linear and parabolic strain hardening characteristics. The interaction relations can predict strains, which is not possible in a rigid, perfectly plastic idealisation. The parameters required are obtained from a standard uniaxial tension test and the procedure can be used for many other materials. [Copyright &y& Elsevier]

OTHER THEMES PUBLISHED IN THIS IMMUNOLOGY IN THE CLINIC REVIEW SERIES Allergy, Metabolic Diseases, Cancer, Autoinflammatory Diseases, Type 1 diabetes and viruses. Summary Invariant natural killer T (iNKT) cells have been shown to play a key role in the regulation of immunity in health and disease. However, iNKT cell responses have also been found to influence both rejection and the induction of tolerance following transplantation of allogeneic cells or organs. Although a number of mechanisms have been identified that lead to iNKT cell activation, how iNKT cells are activated following transplantation remains unknown. This review will attempt to identify potential mechanisms of iNKT cell activation in the context of transplantation by applying knowledge garnered from other disease situations. Furthermore, we put forward a novel mechanism of iNKT cell activation which we believe may be the dominant mechanism responsible for iNKT activation in this setting, i.e. bystander activation by interleukin-2 secreted by recently activated conventional T cells. [ABSTRACT FROM AUTHOR]

Background Third Location Decompression (TLD) is the process through which personnel, returning from combat operations, begin to psychologically ‘unwind’. Decompression comprises welfare activities, such as contacting home, beach events, social events, psycho-educational briefings and controlled re-introduction to alcohol.Aims To assess the subjective utility of decompression by surveying all British troops transiting the TLD facility in Cyprus, during 2008.Methods Analysis of distributed surveys completed by personnel who had deployed either to Iraq or Afghanistan. The main outcome was the subjective utility of the decompression process, with operational exposures, stigma, early post-traumatic stress (PTS) symptoms and adjustment concerns also measured.Results Response rate was 87% (11 304 returned surveys). Eighty per cent of respondents reported being ambivalent or not wanting to go through TLD before decompression; however, on completion, 91% reported finding it useful. The desire to participate was the strongest predictor of perceived helpfulness. Troops who found the TLD less helpful included those who had been through the process before, combat troops and non-commissioned officers. Twelve per cent reported substantial concerns about re-establishing relationships or settling down to ‘normal life’; those reporting more adjustment concerns were more likely to perceive TLD as helpful. Six per cent reported significant PTS symptoms and 27% of troops reported substantial levels of stigma related to mental health and barriers to care.Conclusions TLD was well received by troops following combat deployment. However, TLD does not appear to be equally acceptable to all and alterations to the TLD programme for certain subgroups might be required. [ABSTRACT FROM AUTHOR]

Abstract: Several factors have been identified as determinants of willingness to pay (WTP), including socio-economic and environmental elements. The present article aims to investigate the influence of individual social capital on willingness to pay for environmental goods. In particular, through an empirical study, a multi-dimensional measurement of social capital is conducted and its influence on WTP for water quality improvement is explored. According to the results of the survey it is observed that social capital is a significant explanatory parameter of WTP. [ABSTRACT FROM AUTHOR]

Background Despite having high levels of combat exposure, commando and airborne forces may be at less risk of mental ill-health than other troops.Aims To examine differences in mental health outcomes and occupational risk factors between Royal Marines Commandos (RMCs), paratroopers (PARAs) and other army infantry (INF).Methods Three groups of personnel (275 RMCs, 202 PARAs and 572 INF) were generated from a UK military cohort study of personnel serving at the time of the 2003 Iraq war. Participants completed a questionnaire about their mental health and experiences on deployment. Differences in mental health outcomes between the groups were examined with logistic regression and negative binomial regression analyses.Results Both RMCs and PARAs were less likely to have multiple physical symptoms or to be fatigued, and RMCs also had lower levels of general mental health problems and lower scores on the Post-traumatic Checklist than INF personnel. Differences were not explained by the level of unit cohesion.Conclusions The effect of warfare on troops’ well-being is not universal across occupational groups. A possible explanation for this difference is that the high level of preparedness in RMCs and PARAs may lessen the psychological impact of war-zone deployment experiences. [ABSTRACT FROM AUTHOR]

PurposeTo describe and analyse a method of detailed formal health review for patients with sight-threatening uveitis using oral immunosuppression.MethodsProspective clinical study of 37 patients.ResultsTreatment side effects were absent or tolerable in 31 patients (84%) but 34 significant treatment side effects or other significant clinical findings were newly identified. Ten patients underwent a treatment change including three who transferred to a different immunosuppressive.ConclusionsFormal health review has proved useful in identifying treatment side effects previously not volunteered by patients. A modified form is to be embedded within our clinic management system. We recommend such reviews to enhance drug safety in patients with sight-threatening chronic uveitis using oral immunosuppressives.Eye (2009) 23, 1400–1403; doi:10.1038/eye.2008.270; published online 26 September 2008 [ABSTRACT FROM AUTHOR]

The article presents a study on relaxation-contraction-relaxation cycle of active labor calculating the change in myometrial blood flow using three-dimensional (3D) power Doppler angiography. It presents the methods used in the study in which transabdominal 3D power Doppler ultrasound imaging and 3D datasets were acquired. Findings show a significant decrease of myometrial blood flow during the uterine contraction.

Background: Brief intervention by a health professional can substantially increase smoking cessation rates among patients. However, few studies have collected information on tobacco use and training to provide cessation counselling among health professional students. Objective: To examine tobacco use prevalence and tobacco cessation training among students pursuing advanced degrees in health professions. Methods: The Global Health Professions Student Survey (GHPSS) has been conducted among third-year students attending dental, medical, nursing and pharmacy schools. The GHPSS was conducted in schools during regular lectures and class sessions. GHPSS follows an anonymous, self-administered format for data collection. Results: The GHPSS was completed by at least one of the four target disciplines in 31 countries between 2005 and 2007 for a total of 80 survey sites. In 47 of the 80 sites, over 20% of the students currently smoked cigarettes; and in 29 of 77 sites, over 10% of the students currently used other tobacco products. GHPSS data showed that the majority of health professional students recognised that they are role models in society, believed that they should receive training on counselling patients to quit using tobacco, but in 73 of 80 sites less than 40% of the students reported they received such training. Conclusions: Health professional schools, public health organisations and education officials should discourage tobacco use among health professionals and work together to design and implement programmes that train all health professionals in effective cessation counselling techniques. If the goal of the tobacco control community is to reduce substantially the use of tobacco products, then resources should be invested in improving the quality of education of health professionals with respect to tobacco control. [ABSTRACT FROM AUTHOR]

Phospholipase Cγ1 (PLCγ1) is activated downstream of a variety of extracellular stimuli and has previously been implicated in the regulation of motility responses central to tumour cell invasion. In this study, we used a novel RNAi vector system to achieve conditional PLCγ1 knockdown in PC3LN3 human prostate carcinoma cells for further evaluation of PLCγ1 in tumour cell biology. Using this approach, we revealed a role for PLCγ1 in the regulation of PC3LN3 cell adhesion that appears to be independent of its effects on tumour cell chemotactic migration and spreading in response to extracellular matrix. Subsequent microarray analysis of PLCγ1-knockdown cells revealed Rap GEF1 mRNA to be decreased in response to PLCγ1 loss. This translated into a decrease in Rap GEF1 protein levels and a significant loss of Rap1 activity in PLCγ1-knockdown cells. Transient knockdown of Rap GEF1 caused a reduction in PC3LN3 adhesion while overexpression of Rap GEF1 rescued the PLCγ1 knockdown-induced adhesion defect. These data highlight control of the Rap GEF1–Rap1 molecular switch as a specific requirement for PLCγ1-mediated tumour cell adhesion.Oncogene (2008) 27, 2823–2832; doi:10.1038/sj.onc.1210954; published online 26 November 2007 [ABSTRACT FROM AUTHOR]

The p53-binding protein 53BP1 has been implicated in the DNA damage response and genomic instability. Previous reports have highlighted these roles in vivo in haematopoietic lineages. To investigate the importance of 53BP1 to the DNA damage response in epithelial cells in vivo, we have investigated the role of 53BP1 in mediating apoptosis and proliferation within the murine small intestine following γ-irradiation. 53BP1 deficiency does not affect the immediate response to γ-irradiation with normal levels of apoptosis, proliferation and p53 and p21 accumulation. However, 48 h post-γ-irradiation there was a significant accumulation of cells with much larger nuclei marked by p53 and p21 accumulation. These data reflect increases in polyploidy observed 53BP1−/− deficient fibroblasts following γ-irradiation. At 72 h post-irradiation both the 4N and 8N populations were significantly increased in 53BP1−/− MEFS. Taken together, these results show that following in vivo exposure to γ-irradiation, 53BP1 is dispensable for signalling apoptosis and cell-cycle arrest in the intestinal epithelium. However, it is important for prevention of genomic instability within this epithelial cell population.Oncogene (2007) 26, 6349–6355; doi:10.1038/sj.onc.1210457; published online 23 April 2007 [ABSTRACT FROM AUTHOR]

AimsTo evaluate the efficacy and safety of low-dose (2 mg in 0.05 ml) intraocular triamcinolone injection for patients with uveitis-related cystoid macular oedema and/or intractable intraocular inflammation.Patients and methodsRetrospective clinical case series.ResultsCystoid macular oedema was eliminated in 24/30 eyes (80%). Intractable intraocular inflammation was eliminated in 4/8 eyes (50%). Snellen visual acuity was improved by two lines or more after 14/36 injections (38.9%). Intraocular pressure rose to above 21 mmHg after 8/36 injections (22%). There were no major complications.ConclusionsLow-dose (2 mg in 0.05 ml) intraocular triamcinolone acetonide injection is safe and effective for the management of refractory uveitic macular oedema. Its usefulness in controlling inflammation alone is questionable.Eye (2006) 20, 934–937. doi:10.1038/sj.eye.6702063; published online 12 August 2005 [ABSTRACT FROM AUTHOR]

Abstract: A digraph is mediated if for each pair of distinct vertices of , either or or there is a vertex such that both For a digraph , is the maximum in-degree of a vertex in . The th mediation number is the minimum of over all mediated digraphs on vertices. Mediated digraphs and are of interest in the study of quantum nonlocality. We obtain a lower bound for and determine infinite sequences of values of for which and , respectively. We derive upper bounds for and prove that . We conjecture that there is a constant such that Methods and results of design theory and number theory are used. [Copyright &y& Elsevier]

OBJECTIVE:To investigate the long-term visual results after cataract extraction in patients with uveitis, and to demonstrate the long-term viability of intraocular lenses. DESIGN:In all, 61 patients (72 eyes), with update clinical examination, were retrospectively evaluated. Comparison of preoperative, postoperative, and latest visual function including best-corrected Snellen visual acuity, progression of uveitis and its complications, need for postoperative medical or surgical interventions. RESULTS:After a minimum follow-up of 5 years (mean 7 years 7 months), 82%of eyes maintained a visual improvement of two Snellen lines, 74%maintained 6/9 or better, and 14%had 6/18 or worse. The mode acuity was better than 6/6. The prevalence of macular oedema or scarring was 24%, of posterior capsule opacification 96%, and of glaucoma drainage, 15%. CONCLUSIONS:We report the long-term follow-up of cataract extraction and intraocular lens (IOL) implantation performed by a single surgeon on patients with uveitis attending a regional tertiary referral uveitis clinic. Using stringent perioperative and postoperative control of inflammation, patients with uveitis usually maintain high visual acuity over long-term follow-up. The incidence of sight-threatening postoperative complications is low and no ongoing complication has been attributed to IOL implantation.Eye (2005) 19, 191-197. doi:10.1038/sj.eye.6701450 Published online 2 July 2004 [ABSTRACT FROM AUTHOR]

Recent reports have demonstrated the ability of anti-prion antibodies to inhibit PrPSc propagation. Due to the relatively poor immunogenic properties of both PrPC and PrPSc, the generation of anti-prion antibodies still causes a significant problem in the development of immunotherapeutic strategies. This study examines the potential of multiple antigenic peptides (MAPs) to raise an antibody response to prion derived sequences in mice. The MAP was constructed of a four spiked ring. Two spikes containing human or mouse derived prion amino acid sequences and two spikes containing the universally promiscuous tetanus toxoid sequence (aa 830–844) which was used to assist T-cell-dependent B-cell antibody production. Following vaccinations with the MAP or MAP plus adjuvant, sera were taken and antibody titres assessed. The MAP containing only the mouse sequence failed to elicit a significant antibody response. MAPs containing human prion sequences elicited antibody production to the corresponding prion sequence. Further analysis also demonstrated that these peptides were able to generate antibody responses that recognize conserved human and mouse sequences. These homologous sequences contain the heralded PrPSc specific sequence ‘Tyr-Tyr-Arg’ and therefore these MAPs may have some therapeutic potential. [ABSTRACT FROM AUTHOR]

Structural effectiveness differences have been observed in a recent study on the progressive axial collapse of thin-walled structural sections when made from different classes of steels (mild steel, interstitial-free rephosphorized high-strength steel and high-strength low-alloyed steel). A higher effectiveness was observed for spot-welded top-hat sections made from a mild steel than for similar sections made from a high-strength steel. For square sections, the structural effectiveness was not affected by the steel classes. It is anticipated that this observation applies not only for spot-welded top-hat and square sections, but for other joined and unjoined thin-walled structures as well.The part and full failure of spot-welds, during the axial collapse of the thin-walled structural sections, is one possible explanation for the above inconsistency. This is investigated experimentally in this article using peel tests on spot-weld samples under quasi-static and dynamic conditions. Despite having a lower material strength, the mild steel spot-weld samples exhibited a higher peak force and similar energy absorption during failure when compared with a high-strength steel, both under quasi-static and dynamic loadings.The potential contribution to the mean crushing force during progressive axial collapse is estimated from the experimental results and comparisons are made with deformed thin-walled structural sections from a recent experimental study. Possible implications for the determination of the mean crushing force from analytical and numerical models are identified and discussed. [Copyright &y& Elsevier]

A formal intercomparison of atmospheric total column measurements of N[sub2]O, N[sub2], CH[sub4], O[sub3], HCl, HNO[sub3], and HF by two ground-based solar Fourier transform infrared (FTIR) spectrometers conducted as part of the Network for the Detection of Stratospheric Change (NDSC) instrument certification procedure at Lauder, New Zealand, is presented. The two instruments were nominally very similar, collocated, and collected data at the same times. Collected spectra were analyzed independently by the individual operators in a blind-phase intercomparison, then reanalyzed by a single operator using identical analysis methods to eliminate any potential bias from the spectral analysis. From the consistent reanalysis, gases with predominantly tropospheric distributions and pressure-broadened spectral lines, such as N[sub2]O and CH[sub4], showed differences between retrieved columns of typically less than 1%. For predominantly stratospheric gases, such as HCl and O[sub3], differences were less than 3%. In most cases, the differences were greater than the scatter in the individual measurements and were significant at the 95% confidence level. The worst case observed was for HF, which showed a 7% systematic bias between instruments. The differences are consistent in magnitude with those expected for known types of imperfection in spectrometer alignment and operation, but attempts to quantify these effects through instrument line shape analysis, phase error, zero offsets, and channel spectra did not remove the apparent differences. [ABSTRACT FROM AUTHOR]

ABSTRACT Effects of microstructural modifications, that are a consequence of adding minor grain boundary strengthening elements (C, Hf), on the fatigue response of an experimental single crystal superalloy have been studied. Investigations show that in the modified alloys, as a consequence of the casting process, the population of pores is reduced, but the average pore size increases and larger pores occur close to the fatigue sample surface. Such porosity changes in the modified alloys are an important contributor to their low cycle fatigue (LCF) properties. At the high stress range of LCF tests undertaken, the growth of cracks initiates from pores and their location in the modified alloys are responsible for decreased fatigue lives. At lower stress ranges, crack initiation consumes a considerable proportion of fatigue life. Since crack initiation involves strain localisation at or near the specimen surface where there is interaction with the environment, the population of pores near the specimen surface and the increased length of the tests plays a significant role in governing fatigue lives. The modified alloys benefit from their lower density of pores in the vicinity of the free surface, and tend to have comparable fatigue lives to that of the base alloy at the lower stress level. [ABSTRACT FROM AUTHOR]

Free vibrations of a taut cable with an attached linear viscous damper are investigated in detail using an analytical formulation of the complex eigenvalue problem. This problem is of considerable practical interest in the context of stay-cable vibration suppression in bridges. An expression for the eigenvalues is derived that is independent of the damper coefficient, giving the range of attainable modal damping ratios and corresponding oscillation frequencies in every mode for a given damper location without approximation. This formulation reveals the importance of damper-induced frequency shifts in characterizing the response of the system. New regimes of behavior are observed when these frequency shifts are large, as is the case in higher modes and for damper locations further from the end of the cable. For a damper located sufficiently near the antinode in a given mode, a regime of solutions is identified for which the damping approaches critical as the damper coefficient approaches a critical value. A regime diagram is developed to indicate the type of behavior in each mode for any given damper location. [ABSTRACT FROM AUTHOR]

Free vibrations of a taut cable with a nonlinear power-law damper attached near the end are considered. An approximate analytical solution for the amplitude-dependent effective damping ratios in each mode is developed by assuming the same form of solution as for the linear damper and minimizing the mean-square error in the force equilibrium at the dampen An asymptotic approximate solution for small frequency shifts reveals a nondimensional grouping of parameters allowing the development of an amplitude-dependent "universal estimation curve" for the power-law damper. The shape of the universal curve is slightly different for each value of the damper exponent, but for a given exponent the curve is nearly invariant over the same range of parameters as the universal curve for the linear damper. This formulation yields insights into the dependence of nonlinear damper performance on mode number and amplitude of oscillation, suggesting potential advantages that may be offered by a nonlinear damper over a traditional linear dampen. [ABSTRACT FROM AUTHOR]

Investigation into the addition of minor grain boundary strengthening elements (C, Hf and B) on the properties of an experimented single crystal nickel superalloy has been undertaken. The alloys were subjected to a variety of conditions including thermal exposure at 950°C and creep over 850–1050°C. Detailed microstructural analysis has revealed the presence of script and blocky MC carbides in the eutectic regions. On prolonged exposure σ precipitation occurred close to the MC carbides in the eutectic areas. A significant observation with regard to creep is that the principal crack initiation sites, namely casting pores, are greatly reduced owing to the precipitation of the MC carbides during solidification. This improves the intermediate temperature rupture life, although the presence of retained eutectic regions due to incomplete solidification degrades the high temperature performance of the modified alloys. The morphology of the carbides is a strong function of composition, with the presence of significant levels of Hf leading to the more blocky morphology, which is less prone to fracture during creep. [Copyright &y& Elsevier]

Recent events such as Hurricanes Andrew and Iniki have shown that wind-related disasters occur in the United States with consequences much more far-reaching and severe than expected. During this International Decade for Natural Disaster Mitigation, (1991–2000), the U.S. wind engineering community is calling for the establishment of a wind hazards reduction program analogous in function to the National Earthquake Hazards Reduction Program. This proposed wind hazards program would provide badly needed leadership in improving our understanding of wind-induced structural behavior, in improving codes of practice, in providing advanced methods for evaluating and predicting wind loadings, and in providing an impetus to structural engineers to develop new technologies for improving structural performance. In the present paper, the need for such a program is discussed, and its organization and goals are outlined. [ABSTRACT FROM AUTHOR]

We have found that amino acid residues necessary for Clq and FcγR binding of human IgGl are located in the N-terminal region of the CH2 domain, residues 231--238, using a matched set of engineered antibodies based on the anti-HLA-DR antibody L243. Changing the leucine 235 in the CH2 region of IgG3 and IgG4 to glutamic acid was already known to abolish FcγRl binding. We have confirmed this for IgG1 and also found a concomitant abolition of human complement lysis with retention of FcγRIII-mediated function. Changing the glycine at 237 to alanine of IgG1 also abolished FcγRl binding and reduced human complement lysis and FcγRIII-mediated function. Exchanging the whole region 233-236 with the sequence found in human IgG2, abolished FcγRI binding and human complement lysis and reduced FcγRIII-mediated function of IgG1. In contrast, a change in the previously described C1q-binding motif, from lysine at 320 to alanine, had no effect on IgG1-mediated complement lysis. [ABSTRACT FROM AUTHOR]

The strength of the bond between 125I-labelled Clq and immune complexes, Fc piece, dextran sulphate, polyglutamic acid and polylysine has been investigated. The binding of Clq to Fc piece, small molecular weight (< 10,000) dextran sulphate, polyglutamic acid and polylysine have values for the functional affinity constant (Ko) in the range 0.2-1.5 × 104 M-1. In contrast, the binding of Clq to immune complexes and large molecular weight polyions (> 100,000 is much greater and lies in the range 3×107 - 4×108 M-1. The differences in the binding constants between the two groups can be explained if the Fc piece and small molecular weight compounds bind to only 1 head of the Clq molecule but the immune complexes and large molecules bind to 2 heads. There are probably 6 binding sites on the Clq molecule for dextran sulphate. The enhancement of the binding affinity of Clq by reduction in ionic strength and the reaction with polyions, indicate that ionic groups are present near or within the binding sites. [ABSTRACT FROM AUTHOR]

The strength of the bond between 125I-labelled Clq and immune complexes, Fc piece, dextran sulphate, polyglutamic acid and polylysine has been investigated. The binding of Clq to Fc piece, small molecular weight (< 10,000) dextran sulphate, polyglutamic acid and polylysine have values for the functional affinity constant (Ko) in the range 0.2-1.5 × 104 M-1. In contrast, the binding of Clq to immune complexes and large molecular weight polyions (> 100,000 is much greater and lies in the range 3×107 - 4×108 M-1. The differences in the binding constants between the two groups can be explained if the Fc piece and small molecular weight compounds bind to only 1 head of the Clq molecule but the immune complexes and large molecules bind to 2 heads. There are probably 6 binding sites on the Clq molecule for dextran sulphate. The enhancement of the binding affinity of Clq by reduction in ionic strength and the reaction with polyions, indicate that ionic groups are present near or within the binding sites. [ABSTRACT FROM AUTHOR]

It is well-established that autoantibodies against red cell membrane antigens, such as spectrin are present in plasma of humans and animals. It is shown here that antispectrin IgG antibodies can be eluted from the red cells of patients with β-thalassaemia intermedia. It is suggested that these antibodies could play a part in the increased rate of destruction of red cells in homozygous β-thalassaemia, either by reacting with spectrin which is abnormally exposed on the red cell surface or by a cross-reaction with a different membrane component. No rise was found in serum antispectrin levels in β-thalassaemia; anti-red cell membrane IgG levels were slightly raised, but there was considerable overlap between the levels in patients and in normals. No autoantibody could be found in eluates from cells of normal subjects or patients with sickle cell anaemia. [ABSTRACT FROM AUTHOR]