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The importance of accounting for the temperature dependence of air properties in numerical simulations of air flows over pinned heat sinks is demonstrated by comparisons with recently published experiments. Numerical simulations, based on a conjugate heat transfer analysis, using the RANS-based modified k-ω turbulence model, with temperature-dependent air properties, are shown to be in significantly better agreement with experimental measurements of pressure drop, heat transfer coefficient, and heat sink base temperature, than those which employ constant air properties.

OBJECTIVE: Transient amnesia can be the principal manifestation of epilepsy. This diagnosis, however, is seldom suspected by clinicians and remains controversial. The amnestic attacks are often associated with persistent memory complaints. This study was designed to provide the first description of transient epileptic amnesia in a substantial series of patients. METHODS: Fifty patients were recruited over 18 months using the following diagnostic criteria: (1) recurrent, witnessed episodes of amnesia; (2) other cognitive functions intact during attacks; and (3) compelling evidence of epilepsy. We assessed clinical features and performed neuropsychological evaluation in cases and 24 matched control subjects. RESULTS: Transient epileptic amnesia develops in later life (mean onset, 62 years). Amnestic episodes are frequent (median, 12/year), brief (median duration, 30-60 minutes), and often occur on waking (37/50 cases). Epilepsy was the initial specialist diagnosis in only 12 of 50 cases. Attacks ceased on anticonvulsant medication in 44 of 47 treated patients. A total of 40 of 50 cases described persistent memory difficulties. Despite normal performance on standard memory tests, patients exhibited accelerated forgetting of verbal and visual material over 3 weeks by comparison with matched control subjects (p < 0.001). They also showed loss of autobiographical memories for events extending back over 40 years (p < 0.05). INTERPRETATION: We propose that transient epileptic amnesia is a distinctive epilepsy syndrome, typically misdiagnosed at presentation and associated with accelerated long-term forgetting and autobiographical amnesia. The syndrome is of clinical and theoretic importance.

Background: Self-harm is a major healthcare problem in the United Kingdom, but monitoring of hospital presentations has largely been done separately in single centres. Multicentre monitoring of self-harm has been established as a result of the National Suicide Prevention Strategy for England. Method: Data on self-harm presentations to general hospitals in Oxford (one hospital), Manchester (three hospitals) and Leeds (two hospitals), collected through monitoring systems in each centre, were analysed for the 18-month period March 2000 to August 2001. Results: The findings were based on 7344 persons who presented following 10,498 episodes of self-harm. Gender and age patterns were similar in the three centres, 57.0% of patients being female and two-thirds (62.9%) under 35 years of age. The largest numbers by age groups were 15-19 year-old females and 20-24 year-old males. The female to male ratio decreased with age. Rates of self-harm were higher in Manchester than Oxford or Leeds, in keeping with local suicide rates. The proportion of patients receiving a specialist psychosocial assessment varied between centres and was strongly associated with admission to the general hospital. Approximately 80% of self-harm involved self-poisoning. Overdoses of paracetamol, the most frequent method, were more common in younger age groups, antidepressants in middle age groups, and benzodiazepines and sedatives in older age groups. Alcohol was involved in more than half (54.9%) of assessed episodes. The most common time of presentation to hospital was between 10 pm and 2 am. Conclusions: Multicentre monitoring of self-harm in England has demonstrated similar overall patterns of self-harm in Oxford, Manchester and Leeds, with some differences reflecting local suicide rates. Diurnal variation in time of presentation to hospital and the need for assessment of non-admitted patients have implications for service provision. © Springer-Verlag 2007.

A pre-requisite for sexual reproduction is successful unification of the male and female gametes; in externally-fertilising echinoderms the male gamete is brought into close proximity to the female gamete through chemotaxis, the associated signalling and flagellar beat changes being elegantly characterised in several species. In the human, sperm traverse a relatively high-viscosity mucus coating the tract surfaces, there being a tantalising possible role for chemotaxis. To understand human sperm migration and guidance, studies must therefore employ similar viscous in vitro environments. High frame rate digital imaging is used for the first time to characterise the flagellar movement of migrating sperm in low and high viscosities. While qualitative features have been reported previously, we show in precise spatial and temporal detail waveform evolution along the flagellum. In low viscosity the flagellum continuously moves out of the focal plane, compromising the measurement of true curvature, nonetheless the presence of torsion can be inferred. In high viscosities curvature can be accurately determined and we show how waves propagate at approximately constant speed. Progressing waves increase in curvature approximately linearly except for a sharper increase over a distance 20-27 m from the head/midpiece junction. Curvature modulation, likely influenced by the outer dense fibres, creates the characteristic waveforms of high viscosity swimming, with remarkably effective cell progression against greatly increased resistance, even in high viscosity liquids. Assessment of motility in physiological viscosities will be essential in future basic research, studies of chemotaxis and novel diagnostics.

Background: Self-harm (intentional self-poisoning and self-injury) in children and adolescents is often repeated and is associated with increased risk of future suicide. We have investigated factors associated with these outcomes. Method: We used data collected in the Multicentre Study of Self-harm in England on all self-harm hospital presentations by individuals aged 10-18 years between 2000 and 2007, and national death information on these individuals to the end of 2010. Cox hazard proportional models were used to identify independent and multivariable predictors of repetition of self-harm and of suicide. Results: Repetition of self-harm occurred in 27.3% of individuals (N = 3920) who presented between 2000 and 2005 and were followed up until 2007. Multivariate analysis showed that repetition was associated with age, self-cutting, and previous self-harm and psychiatric treatment. Of 51 deaths in individuals who presented between 2000 and 2007 and were followed up to 2010 (N = 5133) half (49.0%) were suicides. The method used was usually different to that used for self-harm. Multivariate analysis showed that suicide was associated with male gender [Hazard ratio (HR) = 2.4, 95% CI 1.2-4.8], self-cutting (HR = 2.1, 95% CI 1.1-3.7) and prior psychiatric treatment at initial presentation (HR = 4.2, 95% CI 1.7-10.5). It was also associated with self-cutting and history of psychiatric treatment at the last episode before death, and history of previous self harm. Conclusions: Self-cutting as a method of self-harm in children and adolescents conveys greater risk of suicide (and repetition) than self-poisoning although different methods are usually used for suicide. The findings underline the need for psychosocial assessment in all cases. © 2012 The Authors. Journal of Child Psychology and Psychiatry © 2012 Association for Child and Adolescent Mental Health.

Objective: Self-harm and suicide increase in times of economic recession, but little is known about why people self-harm when in financial difficulty, and in what circumstances self-harm occurs. This study aimed to understand events and experiences leading to the episode of self-harm and to identify opportunities for prevention or mitigation of distress.Setting: Participants’ homes or university rooms.Participants: 19 people who had attended hospital following self-harm in two UK cities and who specifically cited job loss, economic hardship or the impact of austerity measures as a causal or contributory factor.Primary and secondary outcome measures: Semistructured, in-depth interviews. Interviews were audio recorded, transcribe8d and analysed cross-sectionally and as case studies.Results: Study participants described experiences of severe economic hardship; being unable to find employment or losing jobs, debt, housing problems and benefit sanctions. In many cases problems accumulated and felt unresolvable. For others an event, such as a call from a debt collector or benefit change triggered the self-harm. Participants also reported other current or past difficulties, including abuse, neglect, bullying, domestic violence, mental health problems, relationship difficulties, bereavements and low self-esteem. These contributed to their sense of despair and worthlessness and increased their vulnerability to self-harm. Participants struggled to gain the practical help they felt they needed for their economic difficulties or therapeutic support that might have helped with their other co-existing or historically damaging experiences.Conclusions: Economic hardships resulting from the recession and austerity measures accumulated or acted as a ‘final straw’ to trigger self-harm, often in the context of co-existing or historically damaging life-experiences. Interventions to mitigate these effects should include providing practical advice about economic issues before difficulties become insurmountable and providing appropriate psychosocial support for vulnerable individuals.

Item does not contain fulltext OBJECTIVE: Comorbid anxiety in depression increases the risk of suicidal ideation and behavior, although data on death by suicide are scarce. We compared characteristics of depressed elderly patients with and without anxiety disorders who died by suicide. METHODS: From a 16-year clinical survey of all suicides in the UK (n = 25,128), we identified 1909 cases aged >/=60 years with a primary diagnosis of depression and no comorbidity other than anxiety disorders. Clinical characteristics of cases with (n = 333, 17.4%) and without (n = 1576) comorbid anxiety disorders were compared by logistic regression adjusted for demographic differences. RESULTS: Compared with cases without comorbid anxiety disorders, cases with comorbid anxiety disorders were more likely to have a duration of illness over 1 year (OR1-5 years = 1.4 [95% CI: 1.0-1.9], p = 0.061; OR>/=5 years = 1.4 [95% CI: 1.6-2.8], p < 0.001), were more frequently prescribed psychotropic drugs other than antidepressants, lithium, and antipsychotics (OR = 2.1 [95% CI: 1.6-2.7], p < 0.001) and were more distressed during their last contact with services (OR = 1.3 [95% CI: 1.0-1.7], p = 0.037). In contrast, clinicians estimated the immediate and long-term suicidal risks lower in those with comorbid anxiety disorders (OR = 0.6 [95% CI: 0.3-0.9], p = 0.011 and OR = 0.7 [95% CI: 0.6-1.0], p = 0.028, respectively). CONCLUSION: Among depressed suicide cases, a comorbid anxiety disorder was identified in one out of six cases and associated with a higher prevalence of several suicide risk factors. This is important, as the detection of anxiety disorders comorbid to depression seems rather low and even when recognized clinicians rated such individuals as at low suicide risk. Copyright (c) 2015 John Wiley & Sons, Ltd.

Data centers are large consumers of power, of which a large proportion is spent on removing the heat generated by the semiconductors inside IT servers. This paper develops a full analysis of the cooling system when servers are immersed in a dielectric liquid and water is used to transport the heat outside of the data center. The analysis combines empirical curve fits and flow analysis with computational fluid dynamics (CFD) simulations of liquid immersed servers placed in parallel in a rack of a data center. The liquid immersed server concept is based on a dielectric liquid that is in direct contact with the semiconductor components to improve heat rejection. The heat generated from the microelectronics is naturally convected, via buoyancy, in the dielectric liquid to a cold plate on the opposing side. The cooling system of the data center in this study consists of a dry air cooler and a liquid-to-liquid buffer heat exchanger. It was found that the power usage effectiveness (PUE) is as low as 1.08 for the cooling system. The results also show that the PUE is affected by the server-rack occupancy and can increase by 26% as occupancy drops by 80%, thus the better the server-rack occupancy, the better the PUE.

Although data on all presentations of self-harm have been collected since 2003, this report focusses on findings from the Manchester Self-Harm (MaSH) Project for the years 2010 and 2011. Section 2 reports on rates from 2003 and 2011.Previous MaSH Reports can be accessed at www.manchester.ac.uk/mash.Self-harm is defined as 'intentional self-injury or self-poisoning, irrespective of .... motivation or degree of suicidal intent', and encompasses both suicide attempts and acts with other motives or intentions (Hawton et al. 2013).

Although data on all presentations of self-harm have been collected since 2003, this report focusses on findings from the Manchester Self-Harm (MaSH) Project for the years 2010 and 2011. Section 2 reports on rates from 2003 and 2011.Previous MaSH Reports can be accessed at www.manchester.ac.uk/mash.Self-harm is defined as 'intentional self-injury or self-poisoning, irrespective of .... motivation or degree of suicidal intent', and encompasses both suicide attempts and acts with other motives or intentions (Hawton et al. 2013).

Drying processes have been with us for a long time. During the Roman Empire, for example, the sun was used as a heat source in the convective drying of bricks, while during the industrial revolution, moist ceramic products were carried into and out of steam heated rooms by child labourers since it was deemed more cost effective to maintain a constant room temperature than to cool the room down in order to remove the products in a safe and healthy manner. Drying is the removal of volatile substances (moisture) by heat from a mixture that yields a solid product [1]. The volatile substances or solvents used in the coating process can range from simple to handle materials such as water to active organic materials where the active ingredients may be polymers, binders, dyes, hardeners etc. The heat supplied during the drying process vaporizes the solvent and the solvent removal must be performed without adversely affecting the coating formulation or interfering with the physical uniformity of the coating. Note that although drying may involve solvent removal, chemical reactions may also aid solidification and it is possible also to accelerate solidification by using a catalyst or an outside energy source such as ultra-violet radiation. This is also called curing to differentiate it from drying although most coatings experience some form of reaction in the dryer. From Keey [1] it may be observed that drying processes for web type substrates can be categorised into conduction, radiation and convection style processes. Conduction processes are characterised by high levels of solid contact and the subsequent high material temperatures associated with this contact. Radiation style processes are generally limited to the drying of thin films as impinging radiation rarely penetrates beyond the immediate surface of a material. The most efficient and hence most frequently implemented drying method is based on convective drying. In this method a carrier gas is heated before being passed over or through the wet material. The convective method is the only method to simultaneously increase the heat transfer coefficient and the mass transfer coefficient [2]. This paper focuses on the convective style of drying. The following figure shows a schematic of two popular air convection drying processes. Figure 1(a) shows a typical air impingement drying process [3] where hot air jets pass over a coated film and transfer heat into the coating to vaporize the solvent. Figure 1(b) shows a schematic of a air floatation dryer [4], which is used to support webs on an air cushion, thereby avoiding possible damage to the web substrate. Figure 1: Schematic diagrams of (a) air impingement and (b) air floatation drying processes [3,4]. Although most coatings are applied in the fluid state, they are used in the dried state. Thus the drying process is as important as the coating process since it may either improve or degrade the properties of the coating. In practice, drying is also important since it may restrict the optimisation of a coating process since in drying sensitive applications drying considerations may dominate over coating ones in limiting possible line speeds. Drying must be performed without adversely affecting the coating formulation or interfering with the physical uniformity of the coating [5].

This report presents rates of self-harm in Manchester, patterns of emergency department attendance and social and clinical characteristics of self-harming individuals. We also place these findings in the context of current research from the MaSH Project and multi-centre self-harm monitoring.

This report presents rates of self-harm in Manchester, patterns of emergency department attendance and social and clinical characteristics of self-harming individuals. We also place these findings in the context of current research from the MaSH Project and multi-centre self-harm monitoring.

Clinical characteristics and risk factors associated with sudden unexplained death (SUD) in the psychiatric population are unclear. Psychiatric in-patients (England, Wales) who met criteria for SUD were identified (1 March 1999-31 December 2005). Cases were matched with controls (in-patients alive on the day a SUD occurred). Data were collected via questionnaires. Some 283 cases of SUD were identified (41 annually), with a rate of 2.33/10,000 mental health admissions (in England). Electrocardiograms were not routine, cardiopulmonary resuscitation equipment was sometimes unavailable, attempts to resuscitate patients were carried out on one-half of all patients and post mortems/inquiries were not routine. Restraint and seclusion were uncommon. Risk factors included: benzodiazepines (odds ratio (OR): 1.83); >/= 2 antipsychotics (OR: 2.35); promazine (OR: 4.02); diazepam (OR: 1.71); clozapine (OR: 2.10); cardiovascular disease (OR: 2.00); respiratory disease (OR: 1.98); diagnosis of dementia (OR: 2.08). Venlafaxine and a diagnosis of affective disorder were associated with reduced ORs (OR: 0.42; OR: 0.65). SUD is relatively rare, although it is more common in older patients and males. Prevention measures may include safer prescribing of antipsychotics and improved physical health care. The contribution of restraint or seclusion to SUD in individual cases is unclear. A uniform definition of SUD may help to identify contributing factors. J Psychopharmacol