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Many preanalytical variables affect the results of coagulation assays. A possible way to control some of them would be to accept blood specimens shipped in the original collection tube. The aim of our study was to investigate the stability of coagulation assays in citrated whole blood transported at ambient temperature for up to two days after specimen collection. Blood samples from 59 patients who attended our haematology outpatient ward for thrombophilia screening were transported at ambient temperature (outdoor during the day, indoor overnight) for following periods of time: <1 hour, 4-6, 8-12, 24-28 and 48-52 hours prior to centrifugation and plasma-freezing. The following coagulation tests were performed: PT, aPTT, fibrinogen, FII:C, FV:C, FVII:C, FVIII:C, FIX:C, FX:C, FXI:C, VWF:RCo, VWF:Ag, AT, PC activity, total and free PS antigen, modified APC-sensitivity-ratio, thrombin-antithrombin-complex and D-dimer. Clinically significant changes, defined as a percentage change of more than 10% from the initial value, were observed for FV:C, FVIII:C and total PS antigen starting at 24-28 hours, and for PT, aPTT and FVII:C at 48-52 hours. No statistically significant differences were seen for fibrinogen, antithrombin, or thrombin-antithrombin complexes (Friedman repeated measures analysis of variance). The present data suggest that the use of whole blood samples transported at ambient temperature may be an acceptable means of delivering specimens for coagulation analysis. With the exception of factor V and VIII coagulant activity, and total PS antigen all investigated parameters can be measured 24-28 hours after specimen collection without observing clinically relevant changes.

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The flammability zone boundaries are very important properties to prevent explosions in the process industries. Within the boundaries, a flame or explosion can occur so it is important to understand these boundaries to prevent fires and explosions. Very little work has been reported in the literature to model the flammability zone boundaries. Two boundaries are defined and studied: the upper flammability zone boundary and the lower flammability zone boundary. Three methods are presented to predict the upper and lower flammability zone boundaries: The linear model The extended linear model, and An empirical model The linear model is a thermodynamic model that uses the upper flammability limit (UFL) and lower flammability limit (LFL) to calculate two adiabatic flame temperatures. When the proper assumptions are applied, the linear model can be reduced to the well-known equation yLOC = zyLFL for estimation of the limiting oxygen concentration. The extended linear model attempts to account for the changes in the reactions along the UFL boundary. Finally, the empirical method fits the boundaries with linear equations between the UFL or LFL and the intercept with the oxygen axis. xx Comparison of the models to experimental data of the flammability zone shows that the best model for estimating the flammability zone boundaries is the empirical method. It is shown that is fits the limiting oxygen concentration (LOC), upper oxygen limit (UOL), and the lower oxygen limit (LOL) quite well. The regression coefficient values for the fits to the LOC, UOL, and LOL are 0.672, 0.968, and 0.959, respectively. This is better than the fit of the "zyLFL" method for the LOC in which the regression coefficient’s value is 0.416.

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BACKGROUND: Caring for a spouse with Alzheimer's disease is associated with increased psychological distress, impaired immunity, and heightened cardiovascular risk. Hyperreactivity of sympathetic and platelet activation responses to acute psychological stress, or the failure to recover quickly from stressful events, may constitute an important pathway linking stress and negative affect with cardiovascular disease (CVD). OBJECTIVES: (1) To evaluate associations between negative affect (i.e., depressive and anxious symptoms) with increased norepinephrine and P-selectin responses to an acute psychological stress task. (2) To establish whether these associations are augmented among elderly spousal caregivers (CG) compared to non-caregivers (NC). METHODS: Depressive (DEP) and anxious (ANX) symptoms from the Brief Symptom Inventory were assessed among 39 CG and 31 NC. Plasma norepinephrine levels (NE) and percent platelet P-selectin (PSEL) expression were assayed at three time-points: rest, immediately following a laboratory speech test (reactivity), and after 14 min of recovery. Results: Among CG, but not NC, increased symptoms of depression and anxiety were associated with delayed NE recovery (DEP: beta=.460, p=.008; ANX: beta=.361, p=.034), increased PSEL reactivity (DEP: beta=.703, p<.001; ANX: beta=.526, p=.002), and delayed PSEL recovery (DEP: beta=.372, p=.039; ANX: beta=.295, p=.092), while controlling for age, gender, aspirin use, antidepressant use, and preexisting CVD. Bivariate correlations showed delayed NE recovery was also associated with increased PSEL reactivity (r=.416) and delayed PSEL recovery (r=.372; all ps<.05) among CG but not NC. DISCUSSION: Among chronically stressed caregivers, increased levels of depressive and anxious symptoms are associated with prolonged sympathetic activation and pronounced platelet activation. These changes may represent one pathway linking caregiving stress to cardiovascular risk.

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The Republic of Buryatia is situated in Eastern Sibiria, the eastern coast of Baikal Lake. The total area of the republic is 351 thousand square kilometers. The capital of Republic is Ulan-Ude. The modern social-economic situation in Russia is extremely paradoxical and multiaspectual - negative processes take place almost in all spheres of the society. The introduction of market economy principles, the process of privatisation, and the last economic crises in the Federation of Russia have brought many social phenomena - among them increasing poverty, homelessness and still high rate of unemployment are the worst one. It makes the changes in the state social welfare programmes and functioning patterns be implemented. Social problems are especially very important in the so-called "depressive" regions of Russia (Buryatia Republic is among those regions). The most important is the staff supplement of social services and the level of professionalism of people who work there. This problem consists of two aspects: first, the number of specialists with professional education of social workers is not enough; second, the level of professionalism of the workers is very low.

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Az állami intézmények tereket hoznak létre azáltal, hogy meghatározott területekre vonatkozóan szabályokat vagy normákat írnak elő. Az ott élő, tevékenykedő emberek használják e tereket, stratégiákat alkotnak, alkalmazkodnak a törvényekhez és piaci viszonyokhoz, kiskapukat keresnek, hogy megélhetésüket, túlélésüket biztosítsák. Eközben ők maguk is olyan tereket hoznak létre, amelyeket a társadalom szimbolikusan értékel vagy stigmatizál. De a terek maguk is alakítják az embereket, lehetőséget biztosítanak számukra, hogy alkalmazkodjanak a feltételekhez, amivel ugyanakkor megteremtik a társadalmi változások alapjait – akárhogyan is alakuljanak e változások. A médiában, a prostitúcióról szóló hírekben a főszereplők jellemzően háttérben maradnak, e tanulmány nekik szentel figyelmet. Ezzel egyidejűleg a szerző megkíséreli a magyarországi nyilvános tereken zajló prostitúciót Budapest, Pécs és Nyíregyháza legkülönfélébb terein megvizsgálni.

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Radon plays an important role for human exposure to natural sources of ionizing radiation. The aim of this article is to compare two approaches to estimate mean radon exposure in the Swiss population: model-based predictions at individual level and measurement-based predictions based on measurements aggregated at municipality level. A nationwide model was used to predict radon levels in each household and for each individual based on the corresponding tectonic unit, building age, building type, soil texture, degree of urbanization, and floor. Measurement-based predictions were carried out within a health impact assessment on residential radon and lung cancer. Mean measured radon levels were corrected for the average floor distribution and weighted with population size of each municipality. Model-based predictions yielded a mean radon exposure of the Swiss population of 84.1 Bq/m(3) . Measurement-based predictions yielded an average exposure of 78 Bq/m(3) . This study demonstrates that the model- and the measurement-based predictions provided similar results. The advantage of the measurement-based approach is its simplicity, which is sufficient for assessing exposure distribution in a population. The model-based approach allows predicting radon levels at specific sites, which is needed in an epidemiological study, and the results do not depend on how the measurement sites have been selected.

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BACKGROUND Anecdotal evidence suggests that the sensitivity and specificity of a diagnostic test may vary with disease prevalence. Our objective was to investigate the associations between disease prevalence and test sensitivity and specificity using studies of diagnostic accuracy. METHODS We used data from 23 meta-analyses, each of which included 10-39 studies (416 total). The median prevalence per review ranged from 1% to 77%. We evaluated the effects of prevalence on sensitivity and specificity using a bivariate random-effects model for each meta-analysis, with prevalence as a covariate. We estimated the overall effect of prevalence by pooling the effects using the inverse variance method. RESULTS Within a given review, a change in prevalence from the lowest to highest value resulted in a corresponding change in sensitivity or specificity from 0 to 40 percentage points. This effect was statistically significant (p < 0.05) for either sensitivity or specificity in 8 meta-analyses (35%). Overall, specificity tended to be lower with higher disease prevalence; there was no such systematic effect for sensitivity. INTERPRETATION The sensitivity and specificity of a test often vary with disease prevalence; this effect is likely to be the result of mechanisms, such as patient spectrum, that affect prevalence, sensitivity and specificity. Because it may be difficult to identify such mechanisms, clinicians should use prevalence as a guide when selecting studies that most closely match their situation.

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Extracellular DNA traps are part of the innate immune response and are seen with many infectious, allergic, and autoimmune diseases. They can be generated by several different leukocytes, including neutrophils, eosinophils, and monocytes, as well as mast cells. Here, we review the composition of these extracellular DNA-containing structures as well as potential mechanisms for their production and function. In general, extracellular DNA traps have been described as binding to and killing pathogens, particularly bacteria, fungi, but also parasites. On the other hand, it is possible that DNA traps contribute to immunopathology in chronic inflammatory diseases, such as bronchial asthma. In addition, it has been demonstrated that they can initiate and/or potentiate autoimmune diseases. Extracellular DNA traps represent a frequently observed phenomenon in inflammatory diseases, and they appear to participate in the cross-talk between different immune cells. These new insights into the pathogenesis of inflammatory diseases may open new avenues for targeted therapies.

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Temperature dependent single-crystal X-ray data were collected on amicite K4Na4(Al8Si8O32)·11H2O from Kola Peninsula (Russia) in steps of 25 °C from room temperature to 175 °C and of 50 °C up to 425 °C. At room temperature amicite has space group I2 with a = 10.2112(1), b = 10.4154(1), c = 9.8802(1) Å, β = 88.458(1)°, V = 1050.416(18) Å3. Its crystal structure is based on a Si–Al ordered tetrahedral framework of the GIS type with two systems of eight-membered channels running along the a and c axes. Extraframework K and Na cations are ordered at two fully occupied sites. Above 75 °C amicite was found to partly dehydrate into two separate but coherently intergrown phases, both of space group I2/a, one K-rich ∼K8(Al8Si8O32) ·4H2O (at 75 °C: a = 10.038(2), b = 9.6805(19), c = 9.843(2) Å, β = 89.93(3)°, V = 956.5(3) Å3) and the other Na-rich ∼Na8(Al8Si8O32)·2H2O (at 75 °C: a = 9.759(2), b = 8.9078(18), c = 9.5270(19) Å, β = 89.98(3)°, V = 828.2(3) Å3). Upon further heating above 75 °C the Na- and K-phases lost remaining H2O with only minor influence on the framework structure and became anhydrous at 175 °C and 375 °C, respectively. The two anhydrous phases persisted up to 425 °C. Backscattered electron images of a heated crystal displayed lamellar intergrowth of the K- and Na-rich phases. Exposed to ambient humid conditions K- and Na-rich phases rehydrated and conjoined to the original one phase I2 structure.