Experiments with rectangular supersonic jets with potential noise reduction technology.

This paper describes the aeroacoustics experiments conducted with supersonic jets, exhausting from rectangular nozzles with an aspect ratio of 2, to examine the jet noise reduction by two different methods. The first method involves the use of fluid inserts, which are produced by distributed air blowing into the diverging section of a convergent-divergent exhaust nozzle. The second method involves the integration of fluid shields in dual flow rectangular jets. In the dual flow nozzle, a single shield below the exit is augmented with fluid shields extending on both sides of the rectangular jet. The purpose of the extended bypass flow is to reduce the noise radiated to the sides of a jet aircraft. In addition to the nozzles with the two noise reduction configurations, acoustic measurements are performed with a single flow rectangular jet, referred to as the baseline. In all cases, the jets are operated as overexpanded, shock-containing jets. In some cases, the jets are operated with the core flow mixtures of helium and air to simulate high temperature jets. The far-field noise measurements are performed on an arc with the microphones approximately 70 equivalent nozzle diameters from the nozzle exit. For the purposes of assessing the noise reduction capability of the dual stream jet, comparisons are made with a baseline rectangular jet on an equal thrust per unit exit area basis. The nondimensional acoustic spectra and overall sound pressure level directivities are shown and compared.

The impact of psychosis on the course of cognition: a prospective, nested case-control study in individuals at clinical high-risk for psychosis.

BACKGROUND: Although cognitive deficits in patients with schizophrenia are rooted early in development, the impact of psychosis on the course of cognitive functioning remains unclear. In this study a nested case-control design was used to examine the relationship between emerging psychosis and the course of cognition in individuals ascertained as clinical high-risk (CHR) who developed psychosis during the study (CHR + T). METHOD: Fifteen CHR + T subjects were administered a neurocognitive battery at baseline and post-psychosis onset (8.04 months, s.d. = 10.26). CHR + T subjects were matched on a case-by-case basis on age, gender, and time to retest with a group of healthy comparison subjects (CNTL, n = 15) and two groups of CHR subjects that did not transition: (1) subjects matched on medication treatment (i.e. antipsychotics and antidepressants) at both baseline and retesting (Meds-matched CHR + NT, n = 15); (2) subjects unmedicated at both assessments (Meds-free CHR + NT, n = 15). RESULTS: At baseline, CHR + T subjects showed large global neurocognitive and intellectual impairments, along with specific impairments in processing speed, verbal memory, sustained attention, and executive function. These impairments persisted after psychosis onset and did not further deteriorate. In contrast, CHR + NT subjects demonstrated stable mild to no impairments in neurocognitive and intellectual performance, independent of medication treatment. CONCLUSIONS: Cognition appears to be impaired prior to the emergence of psychotic symptoms, with no further deterioration associated with the onset of psychosis. Cognitive deficits represent trait risk markers, as opposed to state markers of disease status and may therefore serve as possible predictors of schizophrenia prior to the onset of the full illness.

Organ donation following the circulatory determination of death (DCD): an audit of donation and outcomes following renal transplantation.

Organ Donation following the Circulatory determination of Death was introduced in Beaumont Hospital during 2011. The Intensive Care Society of Ireland formally endorsed a national DCD clinical practice guideline in 2012. This retrospective audit covers a 2-year period during which eleven patients were considered suitable for DCD and where consent was obtained. Nine patients died within the ninety-minute period following the withdrawal of life sustaining therapies and subsequently donated organs (82%). Eighteen kidneys were recovered and seventeen patients received renal transplants--one patient received a nephron-dosing dual renal transplant. Lungs were recovered on two occasions and one patient received a lung transplant. Heart valves were recovered on one occasion. To date sixteen of seventeen recipient patients have functioning renal transplants (94%). In conclusion, this model of deceased donation has proven acceptable to families, nursing and medical staff and the outcomes reported are consistent with international best practice.

Effect of rurality on screening for breast cancer: a systematic review and meta-analysis comparing mammography.

INTRODUCTION: The lower breast cancer survival rate observed among rural women may be related to differences in screening access and utilization. We evaluated existing evidence for rural and urban differences in mammography service use in adult women. METHODS: A systematic search was conducted on 4 April 2012 and updated on 1 November 2012, which yielded 28 studies for inclusion. RESULTS: The rural population was less likely to have mammographic breast screening, and this difference was consistent in various areas of the USA as well as across a number of other countries. Meta-analyses using random effects models showed that women residing in rural areas were less likely than urban women to have ever had a mammogram (odds ratio (OR)=0.74, 95% confidence interval (CI)=0.62-0.89) or to have an up-to-date mammogram (OR=0.59, 95%CI=0.49-0.70). CONCLUSIONS: Mammography is currently the best tool for the early detection and diagnosis of breast cancer. The rural disadvantage this review has identified may contribute to the lower breast cancer survival among women living outside urban areas.

High diversity and widespread occurrence of mitotic spore mats in ectomycorrhizal Pezizales.

Fungal mitospores may function as dispersal units and/ or spermatia and thus play a role in distribution and/or mating of species that produce them. Mitospore production in ectomycorrhizal (EcM) Pezizales is rarely reported, but here we document mitospore production by a high diversity of EcM Pezizales on three continents, in both hemispheres. We sequenced the internal transcribed spacer (ITS) and partial large subunit (LSU) nuclear rDNA from 292 spore mats (visible mitospore clumps) collected in Argentina, Chile, China, Mexico and the USA between 2009 and 2012. We collated spore mat ITS sequences with 105 fruit body and 47 EcM root sequences to generate operational taxonomic units (OTUs). Phylogenetic inferences were made through analyses of both molecular data sets. A total of 48 OTUs from spore mats represented six independent EcM Pezizales lineages and included truffles and cup fungi. Three clades of seven OTUs have no known meiospore stage. Mitospores failed to germinate on sterile media, or form ectomycorrhizas on Quercus, Pinus and Populus seedlings, consistent with a hypothesized role of spermatia. The broad geographic range, high frequency and phylogenetic diversity of spore mats produced by EcM Pezizales suggests that a mitospore stage is important for many species in this group in terms of mating, reproduction and/or dispersal.

Prospective study of cannabis use in adolescents at clinical high risk for psychosis: impact on conversion to psychosis and functional outcome.

BACKGROUND: Clinical and epidemiological studies suggest an association between cannabis use and psychosis but this relationship remains controversial. METHOD: Clinical high-risk (CHR) subjects (age 12-22 years) with attenuated positive symptoms of psychosis (CHR+, n=101) were compared to healthy controls (HC, n=59) on rates of substance use, including cannabis. CHR+ subjects with and without lifetime cannabis use (and abuse) were compared on prodromal symptoms and social/role functioning at baseline. Participants were followed an average of 2.97 years to determine psychosis conversion status and functional outcome. RESULTS: At baseline, CHR+ subjects had significantly higher rates of lifetime cannabis use than HC. CHR+ lifetime cannabis users (n=35) were older (p=0.015, trend), more likely to be Caucasian (p=0.002), less socially anhedonic (p<0.001) and had higher Global Functioning: Social (GF:Social) scores (p<0.001) than non-users (n=61). CHR+ cannabis users continued to have higher social functioning than non-users at follow-up (p<0.001) but showed no differences in role functioning. A small sample of CHR+ cannabis abusers (n=10) showed similar results in that abusers were older (p=0.008), less socially anhedonic (p=0.017, trend) and had higher baseline GF:Social scores (p=0.006) than non-abusers. Logistic regression analyses revealed that conversion to psychosis in CHR+ subjects (n=15) was not related to lifetime cannabis use or abuse. CONCLUSIONS: The current data do not indicate that low to moderate lifetime cannabis use is a major contributor to psychosis or poor social and role functioning in clinical high-risk youth with attenuated positive symptoms of psychosis.

Paediatric forearm fractures in the west of Scotland.

Forearm fractures are common paediatric injuries. This study aimed to describe the epidemiology and treatment of paediatric forearm fractures in the urban population of Glasgow. We reviewed all forearm fractures treated by the orthopaedic service in Yorkhill Children's Hospital in 2008 up to the age of 13 years. Data were gathered from case-notes and radiographs using the prospective orthopaedic database to identify patients with forearm fractures. The age, sex, side and type of fracture, the timing and mechanism of the injury and treatment were documented for the 439 fractures. Census data were used to derive absolute age-specific incidences. Distinction was made between torus and other types of fractures. Torus fractures require no specific orthopaedic treatment and were segregated out. For the remaining 314 fractures, the age and sex distribution, seasonal variation of fractures and treatments for each type of fracture were examined. The incidence of forearm fractures in our population is 411 fractures per 100,000 population per year and 294 fractures per 100,000 population per year for non-torus fractures. An increased number of fractures occurred between May and August. A fall from less than 1 m was the most common mechanism of injury. Sporting injuries were the second most common. This study identifies some features which are in agreement with studies from elsewhere in Britain. However, there are also interesting differences, such as the Glasgow peak incidence for forearm fractures being at age eight, with a marked decline by 12 years. Furthermore, our findings have been extended to consideration of type of intervention and likelihood of successful treatment.

Centrosomes and microtubules during meiosis in the mushroom Boletus rubinellus.

The double centrosome in the basidium of Boletus rubinellus has been observed in three planes with the electron microscope at interphase preceding nuclear fusion, at prophase I, and at interphase I. It is composed of two components connected by a band-shaped middle part. At anaphase I a single, enlarged centrosome is found at the spindle pole, which is attached to the cell membrane. Microtubules mainly oriented parallel to the longitudinal axis of the basidium are present at prefusion, prophase I and interphase I. Cytoplasmic microtubules are absent when the spindle is present. The relationship of the centrosome in B. rubinellus to that in other organisms and the role of the cytoplasmic microtubules are discussed.

Professionals delivering palliative care to people with COPD: qualitative study.

This article describes health and social care professionals' perceptions of palliative care and facilitators and barriers to the delivery of such care for patients with advanced chronic obstructive pulmonary disease. Health professionals participated in semi structured interviews and focus groups which were analysed using content analysis. According to participants, care of patients with chronic obstructive pulmonary disease is focused upon the management of symptoms, with emphasis focused predominately on an acute model of care. Key barriers towards the delivery of palliative care included the reluctance to negotiatie end-of-life decisions and a perceived lack of understanding among patients and carers regarding the illness trajectory. Consequently the delivery of palliative care was viewed as a specialist role rather than an integral component of care. There is a need for education and training for health and social care professions to plan and provide high quality end-of-life care.

Ectomycorrhizal fungal communities of oak savanna are distinct from forest communities.

Oak savanna is one of the most endangered ecosystems of North America, with less than 0.02% of its original area remaining. Here we test whether oak savanna supports a unique community of ectomycorrhizal fungi, a higher diversity of ectomycorrhizal fungi or a greater proportional abundance of ascomycete fungi compared with adjacent areas where the absence of fire has resulted in oak savanna conversion to oak forest. The overall fungal community was highly diverse and dominated by Cenococcum geophilum and other ascomycetes, Cortinarius, Russula, Lactarius and Thelephoraceae. Oak savanna mycorrhizal communities were distinct from oak forest communities both aboveground (sporocarp surveys) and belowground (RFLP identification of ectomycorrhizal root tips); however total diversity was not higher in oak savanna than oak forests and there was no evidence of a greater abundance of ascomycetes. Despite not having a higher local diversity than oak forests, the presence of a unique fungal community indicates that oak savanna plays an important role in maintaining regional ectomycorrhizal diversity.

Comparison of effects of combined ACE inhibitor and low-dose thiazide diuretic with ACE inhibitor alone on insulin action in patients with hypertension and Type 2 diabetes: a double-blind crossover study.

AIMS: To establish the safety in terms of insulin sensitivity of a low dose thiazide/ACE inhibitor combination. METHODS: We examined the effects on insulin sensitivity of captopril either alone or in combination with low-dose bendroflumethiazide (1.25 mg) in 15 hypertensive Type 2 diabetic patients. Insulin action was assessed using an isoglycaemic hyperinsulinaemic clamp in a double-blind, randomised, crossover study after a 6-week placebo run-in and following two 12-week treatment periods with captopril (C) (100 mg) alone or in combination with bendroflumethiazide (CB) (1.25 mg). RESULTS: Blood pressure was lower following CB compare to C (138/83 vs. 144/85 mmHg; P < 0.05) and both were lower than baseline (153/92 mmHg; P < 0.01). CB resulted in a significant increase in fasting plasma glucose compared to C (9.6 +/- 2.6 vs. 8.5 +/- 1.6 mmol/l; P < 0.05). Exogenous glucose infusion rates required to maintain isoglycaemia during hyperinsulinaemia were lower after CB compared to C (25.1 +/- 13.3 vs. 34.2 +/- 16.8 micromol/kg/min; P < 0.01) as were isotopically determined glucose utilisation rates (29.0 +/- 12.4 vs. 36.6 +/- 17.3 micromol/kg/min; P < 0.05). There was no significant difference in fasting endogenous glucose production between treatments (CB 9.3 +/- 3.3 vs. C 8.6 +/- 1.6 micromol/kg/min), nor between suppression following insulin (CB 4.0 +/- 2.1 vs. C 4.3 +/- 3.1 micromol/kg/min). CONCLUSIONS: Combination of low-dose bendroflumethiazide with captopril lowered blood pressure but resulted in deleterious effects on insulin action compared to captopril alone.

I can not get a breath: experiences of living with advanced chronic obstructive pulmonary disease.

This study aims to explore the potential for palliative care among people living with advanced chronic obstructive pulmonary disease (COPD). Individual semi-structured interviews (n=13) were conducted with people who had a diagnosis of advanced COPD and were on optimal tolerated drug therapy, with their breathing volume (forced expiratory volume at less than 30%) or were on long-term oxygen therapy or non-invasion ventilation. Participants raised concerns about the uncertain trajectory of the illness and reported unmet palliative care needs with poor access to palliative care services. For most people, palliative care was associated with end of life; therefore, they were unwilling to discuss the issue. There was a wide acceptance that, medically, nothing more could be done. Findings also suggest that patients had unmet palliative care needs, requiring information and support. The research suggests the need for palliative care to be extended to all (regardless of diagnosis), with packages of care developed to target specific needs.

Hypertriglyceridemia Causing Continuous Renal Replacement Therapy Dysfunction in a Patient with End-stage Liver Disease.

Hypertriglyceridemia is infrequently reported as a cause of suboptimal delivery of dialytic therapy in critically ill patients. We report the case of a critically ill liver transplant patient in the Intensive Care Unit who was found to have recurrent filter clotting during continuous renal replacement therapy (CRRT). The patient had increased serum triglycerides (TGs), which was identified approximately 2 weeks into hospitalization and initially believed to be due to prolonged propofol use. The patient's elevated TGs ultimately caused her blood to become lipemic, causing the dialytic circuit to become nonfunctional and placed the patient in imminent danger due to hyperkalemia and metabolic acidosis. Therapeutic plasma exchange was emergently used to lower TG levels, and renal replacement therapy was resumed without any other issues. The patient's persistent hypertriglyceridemia was attributed to a combination of adverse effect of medications and liver graft failure. The high TG level and abnormal liver functions improved after a repeat liver transplantation.

Listening to people with intellectual disabilities who misuse alcohol and drugs.

There is a dearth of research that has explored alcohol/drug use and misuse by people with intellectual disabilities. The aims of the present study were twofold: (1) to examine the insights of 10 people with intellectual disabilities into the reasons why they may misuse alcohol or drugs, and what impact this behaviour may have on them; and (2) to explore the services that they receive. Ten individuals with intellectual disabilities who were deemed to be misusing alcohol/drugs were purposively selected and interviewed. One overarching theme of the reasons for such misuse was labelled as 'self-medicating against life's negative experiences'. This was divided into two sub-themes: 'psychological trauma' and 'social distance from the community'. All the participants reported that their main source of support came from intellectual disability services, acting in both educational and liaison roles. Although seven of the individuals were referred to mainstream addiction services, they perceived this service as negative. In order to address these underlying problems, better access to a wider range of specialist services is required. Intellectual disability and mainstream addiction service providers also need to be more effective in the prevention and treatment of substance misuse by employing techniques such as motivational interviewing.

Control of dorsal raphé 5-HT function by multiple 5-HT(1) autoreceptors: parallel purposes or pointless plurality?

The serotonergic cells of the dorsal raphé nucleus innervate much of the forebrain and are thought to be involved in the mechanism of action of antidepressants. Dysfunction of these cells might be involved in the neural mechanisms underlying depression and suicide. The traffic in pathways emanating from the dorsal raphé nucleus is controlled by 5-HT(1) autoreceptors. Until recently it was thought that the autoreceptors in the dorsal raphé nucleus were solely of the 5-HT(1A) subtype. In this article, we discuss evidence that the situation is more complex and that multiple 5-HT(1) subtypes govern different aspects of 5-HT function in the dorsal raphé nucleus presenting new therapeutic opportunities.

Expression pattern of the maternally imprinted gene Gtl2 in the forebrain during embryonic development and adulthood.

Recent work has uncovered a large number of imprinted genes, many of which are thought to play a role in neurodevelopment and behavior. In order to begin to understand the role of specific genes in these processes, their expression patterns will be key. In this study we used in situ hybridization to study the developmental expression of Gtl2 in the forebrain from E12.5 to adulthood, since preliminary data from a microarray study indicated differential expression between the ventral and dorsal telencephalon of the mouse at a critical time point in the generation and migration of cortical neuronal populations. Strong expression was observed in the diencephalon, ventral telencephalon, post mitotic cell layers of the neocortex and pyramidal cell layer of the hippocampus. Additionally, heavily labeled subpopulations of laminar restricted cells were seen in the latter two areas.

Assembling the Fungal Tree of Life: constructing the structural and biochemical database.

A major goal of the Assembling the Fungal Tree of Life project is to create a searchable database of selected ultrastructural and biochemical characters from published and new data for use in phylogenetic and other analyses. While developing this database such issues as evaluating specimen fixation quality in published micrographs, organizing data to accommodate characters that were dependent on location and developmental stage, and requiring accountability of data contributors were addressed. Character states for three traits, septal pore apparatus, nuclear division and spindle pole body cycle, are illustrated, and character states are resolved with maximum parsimony and plotted on a summary cladogram of known phylogenetic relationships of the Fungi. The analysis illustrates the inherent phylogenetic signal of these characters, the paucity of comparable characters and character states in subcellular studies and the challenges in establishing a comprehensive structural and biochemical database of the Fungi.

Illicit drug users in Northern Ireland: perceptions and experiences of health and social care professionals.

Over the 30 years of conflict, Northern Ireland escaped the worst excesses of illegal drug trafficking and usage. This was in large part due to the 'policing' of local community crime by paramilitaries. However, since the first 'cease-fire' in 1994 the province has witnessed a dramatic and unprecedented rise in the availability of illicit drugs. This increased availability reflects rising consumption of these drugs in the province. The aim of this study was to explore the perceptions that a sample of health and social care professionals' hold of illicit drug users in Northern Ireland. A survey methodology was used. Community settings across Northern Ireland were accessed. Focus groups and face-to-face interviews were used as data collection methods. Thirty-five health and social care professionals took part in this study. Thirty-two took part in six focus groups; three respondents underwent one-to-one interview. The participating professionals reported to have little or no education or training in the care and treatment of illicit drug users. Some stated that they would reject the offer of education and training in this area to prevent contact with illicit drug users. Many displayed strongly negative views of this client group, often expressing a preference not to care for or treat these people, preferring all their care to be given by specialists in illicit drug treatment. These findings indicate that most of the health and social care professionals who took part in this study appear unprepared and unwilling to meet the challenge of caring for illicit drug users. The findings will be of interest to service providers within and outside the UK.

Ability of nonviable Staphylococcus aureus Cowan I to bind ionized calcium in vitro and ex vivo in an extracorporeal perfusion system.

During immunoadsorption of plasma immunoglobulin G (IgG) and/or its complexes, using nonviable Staphylococcus aureus Cowan I (SA) as an immunoadsorbent, we observed a consistent drop in plasma calcium during every immunoadsorption procedure. The percentage of decrease in plasma calcium was directly dependent on the amount of SA adsorbent present. Although SA can bind both IgG and calcium, the degree of binding of IgG was greater than that of calcium. Calcium could not be detected in the IgG fraction of the plasma SA, however, could bind an appreciable amount of ionized calcium. Extracorporeal perfusion of plasma over SA greatly decreased plasma calcium in a hypercalcemic patient, indicating the feasibility of this method in such patients. Questions concerning the significance of lowering calcium levels as a concomitant of other effects observed in cancer patients undergoing immunoadsorption therapy using SA evolve from the above and become a new focus for attention.

How simple cells are made in a nonlinear network model of the visual cortex.

Simple cells in the striate cortex respond to visual stimuli in an approximately linear manner, although the LGN input to the striate cortex, and the cortical network itself, are highly nonlinear. Although simple cells are vital for visual perception, there has been no satisfactory explanation of how they are produced in the cortex. To examine this question, we have developed a large-scale neuronal network model of layer 4Calpha in V1 of the macaque cortex that is based on, and constrained by, realistic cortical anatomy and physiology. This paper has two aims: (1) to show that neurons in the model respond like simple cells. (2) To identify how the model generates this linearized response in a nonlinear network. Each neuron in the model receives nonlinear excitation from the lateral geniculate nucleus (LGN). The cells of the model receive strong (nonlinear) lateral inhibition from other neurons in the model cortex. Mathematical analysis of the dependence of membrane potential on synaptic conductances, and computer simulations, reveal that the nonlinearity of corticocortical inhibition cancels the nonlinear excitatory input from the LGN. This interaction produces linearized responses that agree with both extracellular and intracellular measurements. The model correctly accounts for experimental results about the time course of simple cell responses and also generates testable predictions about variation in linearity with position in the cortex, and the effect on the linearity of signal summation, caused by unbalancing the relative strengths of excitation and inhibition pharmacologically or with extrinsic current.