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Heat acclimation/acclimatisation (HA) mitigates heat-related decrements in physical capacity and heat-illness risk and is a widely advocated countermeasure for individuals operating in hot environments. The efficacy of HA is typically quantified by assessing the thermo-physiological responses to a standard heat acclimation state test (i.e. physiological biomarkers), but this can be logistically challenging, time consuming, and expensive. A valid molecular biomarker of HA would enable evaluation of the heat-adapted state through the sampling and assessment of a biological medium. This narrative review examines candidate molecular biomarkers of HA, highlighting the poor sensitivity and specificity of these candidates and identifying the current lack of a single ‘standout’ biomarker. It concludes by considering the potential of multivariable approaches that provide information about a range of physiological systems, identifying a number of challenges that must be overcome to develop a valid molecular biomarker of the heat-adapted state, and highlighting future research opportunities.

Northern peatlands are an important source for greenhouse gases, but their capacity to produce methane remains uncertain under changing climatic conditions. We therefore analyzed a 43?year time series of the pore-water chemistry to determine if long-term shifts in precipitation altered the vertical transport of solutes within a large peat basin in northern Minnesota. These data suggest that rates of methane production can be finely tuned to multidecadal shifts in precipitation that drive the vertical penetration of labile carbon substrates within the Glacial Lake Agassiz Peatlands. Tritium and cation profiles demonstrate that only the upper meter of these peat deposits was flushed by downwardly moving recharge from 1965 to 1983 during a Transitional Dry-to-Moist Period. However, a shift to a moister climate after 1984 drove surface waters much deeper, largely flushing the pore waters of all bogs and fens to depths of 2?m. Labile carbon compounds were transported downward from the rhizosphere to the basal peat at this time producing a substantial enrichment of methane in ?14C with respect to the solid-phase peat from 1991 to 2008. These data indicate that labile carbon substrates can fuel deep production zones of methanogenesis that more than doubled in thickness across this large peat basin after 1984. Moreover, the entire peat profile apparently has the capacity to produce methane from labile carbon substrates depending on climate-driven modes of solute transport. Future changes in precipitation may therefore play a central role in determining the source strength of peatlands in the global methane cycle. Methane production zones are finely tuned to climate-driven transport systems in a 7600?km2peat basinDuring dry decades, a weak recharge regime restricts CH4production to shallow peat depthsDuring wetter decades, deeper recharge extends CH4production to the entire peat profile

Heat acclimation/acclimatisation (HA) mitigates heat-related decrements in physical capacity and heat-illness risk and is a widely advocated countermeasure for individuals operating in hot environments. The efficacy of HA is typically quantified by assessing the thermo-physiological responses to a standard heat acclimation state test (i.e. physiological biomarkers), but this can be logistically challenging, time consuming, and expensive. A valid molecular biomarker of HA would enable evaluation of the heat-adapted state through the sampling and assessment of a biological medium. This narrative review examines candidate molecular biomarkers of HA, highlighting the poor sensitivity and specificity of these candidates and identifying the current lack of a single ‘standout’ biomarker. It concludes by considering the potential of multivariable approaches that provide information about a range of physiological systems, identifying a number of challenges that must be overcome to develop a valid molecular biomarker of the heat-adapted state, and highlighting future research opportunities.

Introduction: Accidental immersion in cold water is a risk factor for many occupations. Habituation to cold-water immersion (CWI) is one practical means of reducing the cold shock response (CSR) on immer-sion. We investigated whether repeated thermoneutral water immersion (TWI) induced a perceptual habituation (i.e., could lessen perceived threat and anxiety) and consequently reduce the CSR on subsequent CWI. Methods: There were 12 subjects who completed seven 7-min head-out immersions. Immersions one and seven were CWIs (15.0 (0.1 )°C], and immersions two to six wereTWI [34.9 (0.10)°C]. Anxiety (20-cm visual analogue scale) and the cardiorespiratory responses [heart rate (fc), respiratory frequency (fR), tidal volume (VT), and minute venti-lation (VE)[ to immersionwere measured throughout. Data were com-pared within subject between conditions using ANOVA to an alpha level of 0.05. Results: Acute anxiety was significantly reduced after repeated exposure to the immersion scenario (i.e., TWI): CWI-1: 6.3 (4.4) cm; and CWI-2: 4.5 (4.0) cm [condition mean (SD)l. These differences did not influence the peak in the CSR. The fc, fR, and VE responses were similar between CWI-1 and CWI-2. VT response was significantly lower in CWI-2; mean (SD) across the immersion: CWI-1 1.27 (0.17) vs. CWI-2 1.11 (0.2) L. Discussion: Repeated TWI lessened the anxiety associated with CWI (perceptual habituation). This had a negligible effect on the primary components of the CSR, but did lower VT, which may reduce the volume of any aspirated water in an emergency situation. Reducing the threat appraisal of an environmental stressor may be a useful biproduct of survival training, thereby minimizing psychophysiological strain. [ABSTRACT FROM AUTHOR]

The performance of a porous-ceramic hydrostatic journal bearing manufactured by the starch consolidation (SC) technique has been examined using a highly instrumented test rig. The results have been compared with those of a 5-recess hydrostatic bearing of the same size and comparable design, under the same testing conditions. The SC porous-ceramic bearing showed an improved performance over the conventional hydrostatic bearing. Static and rotational stiffness were 95 per cent and over 150 per cent higher, respectively. In addition, the porous ceramic bearing exhibited a more economic performance with a 64 per cent lower flowrate and pumping power than the hydrostatic bearing. In terms of heat generation, the porous ceramic bearing showed 50 per cent lower temperature rise.

To compare the characteristics of idiopathic intracranial hypertension (IIH) in men vs women in a multicenter study.

To evaluate recurrent or delayed worsening of papilledema and visual function in patients with idiopathic intracranial hypertension (IIH) followed for more than 10 years.

A retrospective review was conducted to determine the safety and efficacy of ezetimibe as a treatment option for renal transplant recipients. We evaluated the medical records of 34 adult renal transplant recipients receiving ezetimibe as monotherapy or combination therapy. Fasting lipid profiles were obtained at baseline and at 1–6 months post‐ezetimibe initiation. Twenty patients received cyclosporine, 12 patients received tacrolimus, 1 patient received either sirolimus or no calcineurin therapy at the time of ezetimibe initiation. Monotherapy was started in 8 patients, who had all previously failed statins, and combination therapy was utilized in 26 patients. Monotherapy or combination therapy resulted in a mean reduction in total cholesterol of 23.3%, triglycerides 40.2%, low‐density lipoproteins 16.8% and high‐density lipoproteins 4.8% after 3.1 months of therapy. Ezetimibe as combination or monotherapy is a safe and effective treatment option for dyslipidemia in renal transplant recipients without changes in calcineurin inhibitor levels or renal function.

A retrospective review was conducted to determine the safety and efficacy of ezetimibe as a treatment option for renal transplant recipients. We evaluated the medical records of 34 adult renal transplant recipients receiving ezetimibe as monotherapy or combination therapy. Fasting lipid profiles were obtained at baseline and at 1–6 months post-ezetimibe initiation. Twenty patients received cyclosporine, 12 patients received tacrolimus, 1 patient received either sirolimus or no calcineurin therapy at the time of ezetimibe initiation. Monotherapy was started in 8 patients, who had all previously failed statins, and combination therapy was utilized in 26 patients. Monotherapy or combination therapy resulted in a mean reduction in total cholesterol of 23.3%, triglycerides 40.2%, low-density lipoproteins 16.8% and high-density lipoproteins 4.8% after 3.1 months of therapy. Ezetimibe as combination or monotherapy is a safe and effective treatment option for dyslipidemia in renal transplant recipients without changes in calcineurin inhibitor levels or renal function.

A retrospective review was conducted to determine the safety and efficacy of ezetimibe as a treatment option for renal transplant recipients. We evaluated the medical records of 34 adult renal transplant recipients receiving ezetimibe as monotherapy or combination therapy. Fasting lipid profiles were obtained at baseline and at 1–6 months post-ezetimibe initiation. Twenty patients received cyclosporine, 12 patients received tacrolimus, 1 patient received either sirolimus or no calcineurin therapy at the time of ezetimibe initiation. Monotherapy was started in 8 patients, who had all previously failed statins, and combination therapy was utilized in 26 patients. Monotherapy or combination therapy resulted in a mean reduction in total cholesterol of 23.3%, triglycerides 40.2%, low-density lipoproteins 16.8% and high-density lipoproteins 4.8% after 3.1 months of therapy. Ezetimibe as combination or monotherapy is a safe and effective treatment option for dyslipidemia in renal transplant recipients without changes in calcineurin inhibitor levels or renal function.

Alcohol dependence is a complex disorder with a substantial genetic contribution to susceptibility. The Collaborative Study on the Genetics of Alcoholism is a multi-site study whose purpose is to detect, localize, and characterize genes contributing to this susceptibility. Previous linkage analyses of the trait of alcohol dependence in Collaborative Study on the Genetics of Alcoholism have used affected sib-pair methods with a dichotomous phenotype definition. In contrast, the analysis in this paper uses a sex-adjusted and age-adjusted multiple threshold liability model. The use of such a model, in that it includes unaffected as well as as affected subjects and in that it utilizes the differential severity of a diagnosis scale, should heuristically be more powerful than a straight affected sib-pair analysis. Three regions of interest are found on chromosome 1 (lod 5.17), chromosome 4 (lod 3.46), and chromosome 8 (lod 4.31). The region on chromosome 1 near the marker D1S532 is in the region previously reported as linked to alcohol dependence and correlated phenotypes in this dataset. The region on chromosome 4 near the alcohol dehydrogenase gene cluster has been reported to be linked to alcohol dependence in other studies, as well as to the alcohol consumption phenotype ‘Maximum Number of Drinks in a 24-Hour Period’ in this dataset. The region on chromosome 8 near the marker D8S1988 is homologous to a section of rat chromosome 5 to which an alcohol consumption phenotype has been linked.

The specification activity is a critical enabler for collaborative product development through an extended enterprise. Often this activity involves numerous iterations before a shared understanding of the product requirements is achieved since various omissions, ambiguities and assumptions have to be resolved. This paper will present a framework for the electronic-enabling of the requirements founded on ontology-based constructs to provide a shared conceptualisation of the knowledge needed for the specification of a product. The application of ontology is a means to establish the consensual knowledge about the needs of a product and to then apply this shared understanding for its specification.

AbstractObjectives: Some traits, while naturally polychotomous, are routinely dichotomized for genetic analysis. Dichotomization, intuitively, leads to a loss of power to detect linkage, as some phenotypic variability is discarded. This paper examines this power loss in the context of a trichotomous trait. Methods: To examine this power loss, we performed a simulation study where a trichotomous trait was simulated in a sample of 1,000 sib-pairs under various genetic models. The study was replicated 1,000 times. Linkage analysis using a variance components method, as implemented in Mx, was then performed on the trichotomous trait and compared with that on a dichotomized version of the trait. Results: A comparison of the power and false positive rates of the analyses shows that power to detect linkage was increased by up to 22 percentage points simply by examining the trait as a trichotomy instead of a dichotomy. Under all models examined, the trichotomous analysis outperformed the dichotomous version. Conclusions: Comparable levels of false positive rates under both methods confirm that this power gain comes solely from the information lost upon dichotomization. Thus, dichotomizing tri- or poly-chotomous traits can lead to crippling power loss, especially in the case of many loci of small effect.Copyright © 2004 S. Karger AG, Basel

The design of a turbine blade cooling system is a multi-objective optimisation problem involving constraints and complex Interaction among its design variables. The aim of this paper is to develop a methodology to optimise this design using Evolutionary Computing techniques. This paper presents Generalised Regression Genetic Algorithm (GRGA) and the mathematical model of a real-life turbine blade cooling system. Even in the presence of variable interaction, the methodology identifies a number of good feasible designs from which one could be finally chosen based on designer's preferences. The research also demonstrates that GRGA is capable of optimising a real-life design.

Cranfield Precision, Division of Landis Lund, has recently developed an ultraprecision face grinding machine which incorporates several automatic supervision features. The company supplied the machine to Cranfield University’s Precision Engineering Group in order that the group can undertake research, particularly in the area of damage-free grinding with high surface and subsurface integrity. The paper discusses the design of the machine, initial machining trials and potential research projects. Such projects will benefit from the availability of such an advanced machine system which incorporates many state-of-the-art features for the automatic supervision and control of the machining process.:

High efficiency deep grinding (HEDG) of a low alloy steel (51CrV4) has been carried out on an Edgetek 5-axis CNC grinding machine, using electroplated CBN wheels. The initial tests were conducted in a surface grinding mode over a wide range of grinding conditions, to evaluate the levels of specific grinding energy, workpiece surface integrity and wheel wear. The burn threshold conditions for the ground workpiece surface have been proposed in terms of a critical heat flux which is shown to vary with material removal rate. Cylindrical grinding in HEDG mode has also been carried out based on the knowledge obtained from the surface grinding. It has shown that the HEDG technology can be transferred successfully to the field of cylindrical grinding to achieve very high specific material removal rates in excess of 400mm3/mm.s. The successful application of HEDG to cylindrical components depends on the appropriate selection of grinding parameters and also the grinding fluid supply strategy. Thermal modelling of the HEDG process combined with surface integrity studies, has shown that under cylindrical grinding conditions a significant reduction in grinding fluid supply is possible even when operating within the HEDG regime.

A series of 4-alkenyl and 4-alkynyl-3,4-dihydro-4-(trifluoromethyl)-2-(1H)-quinazolinones were found to be potent non-nucleoside reverse transcriptase inhibitors (NNRTIs) of human immunodeficiency virus type-1 (HIV-1). The 4-alkenyl-3,4-dihydro-4-(trifluoromethyl)-2-(1H)-quinazolinones DPC 082 and DPC 083 and the 4-alkynyl-3,4-dihydro-4-(trifluoromethyl)-2-(1H)-quinazolinones DPC 961 and DPC 963 were found to exhibit low nanomolar potency toward wild-type RF virus (IC90 = 2.0, 2.1, 2.0, and 1.3 nM, respectively) and various single and many multiple amino acid substituted HIV-1 mutant viruses. The increased potency is combined with favorable plasma serum protein binding as demonstrated by improvements in the percent free drug in human plasma when compared to efavirenz:  3.0%, 2.0%, 1.5%, 2.8%, and 0.2−0.5% for DPC 082, DPC 083, DPC 961, DPC 963, and efavirenz, respectively.

The clinical utility of the Thrombotest, a method for determining the prothrombin time that is uniquely sensitive to the presence of proteins invoked by vitamin K absence (PIVKA), was prospectively evaluated and compared to routine coagulation tests in cats with clinically suspected bleeding tendencies. Abnormal PIVKA clotting values were determined by comparison to results of a concurrently evaluated pooled feline plasma sample and by use of an absolute cutoff value of 25.2 seconds. To be recognized as abnormal, PIVKA clotting values had to be >20% of the pooled feline plasma PIVKA clotting time (the “20% rule”) or ≥25.2 seconds (mean + 2 standard deviations of 150 different pooled feline plasma samples). Among the disorders in the population examined were 74 cats with liver disease and 19 cats with severe inflammatory bowel disease. Overall, a prolonged PIVKA clotting time based on the 25.2‐second cutoff was found in 39.3% of cats, and based on the 20% rule in 40.7% of cats. An abnormal prothrombin time (PT) developed in 5.8% of cats, an abnormal APTT in 14% of cats, subnormal fibrinogen in 8.8% of cats, and thrombocytopenia in 3.3% of cats. Bleeding tendencies were confirmed in 22 cats, of which abnormal PIVKA clotting times were recognized in 95.5%, abnormal PT in 21%, abnormal activated partial thromboplastin time in 25%, hypofibrinogenemia in 16.7%, and thrombocytopenia in 4.5%. Response to treatment with vitamin K was demonstrated in 21 of 24 cats with an abnormal PIVKA clotting time. In these cats, an abnormal PIVKA clotting time normalized within 3 to 5 days of parenteral vitamin K administration. Cats responding to vitamin K administration had hepatic lipidosis (n = 7), severe inflammatory bowel disease (n = 4), severe inflammatory bowel disease associated with cholangiohepatitis (n = 5), and miscellaneous disorders (n = 5). Using either endpoint, the PIVKA clotting time is more sensitive for the detection of cats with coagulopathies than routinely used coagulation assessments in our hospital. Our findings confirm that cats with hepatic lipidosis, severe cholangiohepatitis, and severe inflammatory bowel disease develop coagulopathies responsive to vitamin K administration.

Nanotechnology is becoming vitally important in many industrial fields, offering significant wealth creating opportunities and massive improvements to standards of living. This paper describes the current state-of-the-art, emphasises its multi-disciplinary nature and conveys the enormous impact that nanotechnology will progressively make on materials, product and process research and thence on to manufacturing technologies, industry and the economies of countries throughout the world.

Cyclohexanone oxime (CHOX), an intermediate used in the synthesis of polycaprolactam (Nylon-6), has been reported to be hematotoxic in Fischer rats. The in vivo metabolism of CHOX was found to release nitric oxide, which was detected in venous blood by electron paramagnetic resonance spectroscopy as the nitrosylhemoglobin complex. In vitro incubation of CHOX with venous blood resulted in the formation of the characteristic nitrosylhemoglobin complex, suggesting that the blood was a possible site for metabolism. Excessive nitric oxide production may, in part, contribute to the observed toxicity of CHOX.

The primary purpose was to investigate whether serum vitamin A concentration is associated with idiopathic intracranial hypertension (IIH). The secondary aim was to obtain pilot data regarding the amount of vitamin A ingested by patients and controls.

In this study, the ability of interferon-gamma (IFN-gamma) to prime rat and nonobese diabetic (NOD) mouse islets for interleukin-1 (IL-1)-stimulated expression of inducible nitric-oxide synthase (iNOS) has been examined. IL-1-induced iNOS expression by rat islets is concentration-dependent with maximal expression occurring in response to 1.0 unit/ml. Individually, neither 0.1 unit/ml IL-1 nor 150 units/ml IFN-gamma stimulates iNOS expression or nitrite production by rat islets. However, a 30-60-min pulse of rat islets with IFN-gamma, followed by washing to remove the cytokine and continued culture with 0.1 unit/ml IL-1 for 40 h, results in iNOS expression and nitrite production to levels similar in magnitude to the individual effects of 1.0 unit/ml IL-1. A 1-h pulse with IFN-gamma primes for IL-1-induced islet degeneration that is mediated by the expression of iNOS and increased production of nitric oxide. IFN-gamma also primes for IL-1-induced iNOS expression and nitrite formation by NOD mouse islets. The priming actions of IFN-gamma appear to be selective for beta-cells, as IFN-gamma primes for IL-1-induced nitrite formation by primary beta-cells and RINm5F insulinoma cells, but not primary alpha-cells. The priming actions of IFN-gamma for IL-1-induced iNOS expression do not require de novo protein synthesis as preincubation of RINm5F cells with cycloheximide does not inhibit iNOS mRNA accumulation under priming conditions. The priming actions of IFN-gamma on IL-1-induced iNOS expression persists for extended periods of up to 7 days and are associated with persistent signal transducers and activators of transcription (STAT)-1 activation. A 30-min pulse of rat islets with IFN-gamma stimulates STAT1 phosphorylation, and STAT1 remains phosphorylated for up to 7 days following IFN-gamma removal. In addition, STAT1 remains nuclear for up to 7 days after IFN-gamma removal. These results indicate that IFN-gamma primes for IL-1-induced islet degeneration via a nitric oxide-dependent mechanism. These findings also provide evidence that the priming actions of IFN-gamma for IL-1-induced iNOS expression by islets are associated with the prolonged phosphorylation and activation of STAT1.

Viral infection has been implicated as a triggering event that may initiate beta-cell damage during the development of autoimmune diabetes. In this study, the effects of the viral replicative intermediate, double-stranded RNA (dsRNA) (in the form of synthetic polyinosinic-polycytidylic acid (poly IC)) on islet expression of inducible nitric oxide synthase (iNOS), production of nitric oxide, and islet function and viability were investigated. Treatment of rat islets with poly(IC) + interferon-gamma (IFN-gamma) stimulates the time- and concentration-dependent expression of iNOS and production of nitrite by rat islets. iNOS expression and nitrite production by rat islets in response to poly(IC) + IFN-gamma correlate with an inhibition of insulin secretion and islet degeneration, effects that are prevented by the iNOS inhibitor aminoguanidine (AG). We have previously shown that poly(IC) + IFN-gamma activates resident macrophages, stimulating iNOS expression, nitric oxide production and interleukin-1 (IL-1) release. In addition, in response to tumor necrosis factor-alpha (TNF-alpha) + lipopolysaccharide, activated resident macrophages mediate beta-cell damage via intraislet IL-1 release followed by IL-1-induced iNOS expression by beta-cells. The inhibitory and destructive effects of poly(IC) + IFN-gamma, however, do not appear to require resident macrophages. Treatment of macrophage-depleted rat islets for 40 h with poly(IC) + IFN-gamma results in the expression of iNOS, production of nitrite, and inhibition of insulin secretion. The destructive effects of dsRNA + IFN-gamma on islets appear to be mediated by a direct interaction with beta-cells. Poly IC + IFN-gamma stimulates iNOS expression and inhibits insulin secretion by primary beta-cells purified by fluorescence-activated cell sorting. In addition, AG prevents the inhibitory effects of poly(IC) + IFN-gamma on glucose-stimulated insulin secretion by beta-cells. These results indicate that dsRNA + IFN-gamma interacts directly with beta-cells stimulating iNOS expression and inhibiting insulin secretion in a nitric oxide-dependent manner. These findings provide biochemical evidence for a novel mechanism by which viral infection may directly mediate the initial destruction of beta-cells during the development of autoimmune diabetes.