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The Paippaladasamhita of the Atharvaveda: Kandas 6 and 7. A New Edition with Translation and Commentary. By ARLO GRIFFITHS. Groningen Oriental Studies, vol. 22. Groningen: EGBERT FORSTEN, 2009. Pp. Ixxxvi [...]

Background As the prevalence of hypercholesterolemia is increasing in low- and middle-income countries (LMICs), detailed evidence is urgently needed to guide the response of health systems to this epidemic. This study sought to quantify unmet need for hypercholesterolemia care among adults in 35 LMICs. Methods and findings We pooled individual-level data from 129,040 respondents aged 15 years and older from 35 nationally representative surveys conducted between 2009 and 2018. Hypercholesterolemia care was quantified using cascade of care analyses in the pooled sample and by region, country income group, and country. Hypercholesterolemia was defined as (i) total cholesterol (TC) [greater than or equal to]240 mg/dL or self-reported lipid-lowering medication use and, alternatively, as (ii) low-density lipoprotein cholesterol (LDL-C) [greater than or equal to]160 mg/dL or self-reported lipid-lowering medication use. Stages of the care cascade for hypercholesterolemia were defined as follows: screened (prior to the survey), aware of diagnosis, treated (lifestyle advice and/or medication), and controlled (TC High TC prevalence was 7.1% (95% CI: 6.8% to 7.4%), and high LDL-C prevalence was 7.5% (95% CI: 7.1% to 7.9%). The cascade analysis showed that 43% (95% CI: 40% to 45%) of study participants with high TC and 47% (95% CI: 44% to 50%) with high LDL-C ever had their cholesterol measured prior to the survey. About 31% (95% CI: 29% to 33%) and 36% (95% CI: 33% to 38%) were aware of their diagnosis; 29% (95% CI: 28% to 31%) and 33% (95% CI: 31% to 36%) were treated; 7% (95% CI: 6% to 9%) and 19% (95% CI: 18% to 21%) were controlled. We found substantial heterogeneity in cascade performance across countries and higher performances in upper-middle-income countries and the Eastern Mediterranean, Europe, and Americas. Lipid screening was significantly associated with older age, female sex, higher education, higher BMI, comorbid diagnosis of diabetes, and comorbid diagnosis of hypertension. Awareness of diagnosis was significantly associated with older age, higher BMI, comorbid diagnosis of diabetes, and comorbid diagnosis of hypertension. Lastly, treatment of hypercholesterolemia was significantly associated with comorbid hypertension and diabetes, and control of lipid measures with comorbid diabetes. The main limitations of this study are a potential recall bias in self-reported information on received health services as well as diminished comparability due to varying survey years and varying lipid guideline application across country and clinical settings. Conclusions Cascade performance was poor across all stages, indicating large unmet need for hypercholesterolemia care in this sample of LMICs-calling for greater policy and research attention toward this cardiovascular disease (CVD) risk factor and highlighting opportunities for improved prevention of CVD., Author(s): Maja E. Marcus 1,*, Cara Ebert 2, Pascal Geldsetzer 3,4, Michaela Theilmann 4, Brice Wilfried Bicaba 5, Glennis Andall-Brereton 6, Pascal Bovet 7,8, Farshad Farzadfar 9, Mongal Singh Gurung [...]

Background Global cardiovascular disease (CVD) burden is high and rising, especially in low-income and middle-income countries (LMICs). Focussing on 45 LMICs, we aimed to determine (1) the adult population's median 10-year predicted CVD risk, including its variation within countries by socio-demographic characteristics, and (2) the prevalence of self-reported blood pressure (BP) medication use among those with and without an indication for such medication as per World Health Organization (WHO) guidelines. Methods and findings We conducted a cross-sectional analysis of nationally representative household surveys from 45 LMICs carried out between 2005 and 2017, with 32 surveys being WHO Stepwise Approach to Surveillance (STEPS) surveys. Country-specific median 10-year CVD risk was calculated using the 2019 WHO CVD Risk Chart Working Group non-laboratory-based equations. BP medication indications were based on the WHO Package of Essential Noncommunicable Disease Interventions guidelines. Regression models examined associations between CVD risk, BP medication use, and socio-demographic characteristics. Our complete case analysis included 600,484 adults from 45 countries. Median 10-year CVD risk (interquartile range [IQR]) for males and females was 2.7% (2.3%-4.2%) and 1.6% (1.3%-2.1%), respectively, with estimates indicating the lowest risk in sub-Saharan Africa and highest in Europe and the Eastern Mediterranean. Higher educational attainment and current employment were associated with lower CVD risk in most countries. Of those indicated for BP medication, the median (IQR) percentage taking medication was 24.2% (15.4%-37.2%) for males and 41.6% (23.9%-53.8%) for females. Conversely, a median (IQR) 47.1% (36.1%-58.6%) of all people taking a BP medication were not indicated for such based on CVD risk status. There was no association between BP medication use and socio-demographic characteristics in most of the 45 study countries. Study limitations include variation in country survey methods, most notably the sample age range and year of data collection, insufficient data to use the laboratory-based CVD risk equations, and an inability to determine past history of a CVD diagnosis. Conclusions This study found underuse of guideline-indicated BP medication in people with elevated CVD risk and overuse by people with lower CVD risk. Country-specific targeted policies are needed to help improve the identification and management of those at highest CVD risk., Author(s): David Peiris 1,*, Arpita Ghosh 2,3, Jennifer Manne-Goehler 4, Lindsay M. Jaacks 5, Michaela Theilmann 4, Maja E. Marcus 6, Zhaxybay Zhumadilov 7, Lindiwe Tsabedze 8, Adil Supiyev 9, [...]

Despite strong evidence for the importance of charcoal as a long-term carbon sink in soils, simple methods to quantify charcoal in soil are still lacking. In this study, we tested the application of attenuated total reflectance mid-infrared spectroscopy (ATR-MIR) for quantification of charcoal in soil. To do this, we created calibration samples from defined quantities of pulverised rock, charcoal and litter sampled from a forest floor in Guy Fawkes National Park, New South Wales, Australia, and analysed them via ATR-MIR and dry combustion. The organic carbon concentration (mass proportion) of the samples ranged from 0.1 to 15% and the charcoal mass proportion from 0.02-11 % (10-50% of soil organic matter). We then trained randomForcst models to the spectral data and assessed the predictive performance of the models for both the quantity of charcoal and litter in the samples. The models were excellent at predicting both charcoal and litter contents of the samples, explaining 94% of variance in the mass proportion of charcoal and 93% of the variance in the litter content of the validation dataset (i.e. out-of-bag estimates of the models). Extracting the variable importance from the models showed that the spectral regions important to charcoal prediction differed from those important to litter prediction, highlighting the capacity of the models to distinguish between charcoal and litter components based upon ATR-MIR spectra. Our method enables a simple, cheap and efficient prediction of litter and charcoal without the need for complex chemical extraction or analyses. Additional keywords: ATR-MIR black carbon, machine learning, randomForest, soil pyrogenic matter., Introduction Pyrogenic carbon--also referred to as black carbon--is a product of the incomplete combustion of organic matter. Charcoal is a particulate form of pyrogenic carbon, which can be well preserved [...]

Background Cardiovascular diseases are leading causes of death, globally, and health systems that deliver quality clinical care are needed to manage an increasing number of people with risk factors for these diseases. Indicators of preparedness of countries to manage cardiovascular disease risk factors (CVDRFs) are regularly collected by ministries of health and global health agencies. We aimed to assess whether these indicators are associated with patient receipt of quality clinical care. Methods and findings We did a secondary analysis of cross-sectional, nationally representative, individual-patient data from 187,552 people with hypertension (mean age 48.1 years, 53.5% female) living in 43 low- and middle-income countries (LMICs) and 40,795 people with diabetes (mean age 52.2 years, 57.7% female) living in 28 LMICs on progress through cascades of care (condition diagnosed, treated, or controlled) for diabetes or hypertension, to indicate outcomes of provision of quality clinical care. Data were extracted from national-level World Health Organization (WHO) Stepwise Approach to Surveillance (STEPS), or other similar household surveys, conducted between July 2005 and November 2016. We used mixed-effects logistic regression to estimate associations between each quality clinical care outcome and indicators of country development (gross domestic product [GDP] per capita or Human Development Index [HDI]); national capacity for the prevention and control of noncommunicable diseases ('NCD readiness indicators' from surveys done by WHO); health system finance (domestic government expenditure on health [as percentage of GDP], private, and out-of-pocket expenditure on health [both as percentage of current]); and health service readiness (number of physicians, nurses, or hospital beds per 1,000 people) and performance (neonatal mortality rate). All models were adjusted for individual-level predictors including age, sex, and education. In an exploratory analysis, we tested whether national-level data on facility preparedness for diabetes were positively associated with outcomes. Associations were inconsistent between indicators and quality clinical care outcomes. For hypertension, GDP and HDI were both positively associated with each outcome. Of the 33 relationships tested between NCD readiness indicators and outcomes, only two showed a significant positive association: presence of guidelines with being diagnosed (odds ratio [OR], 1.86 [95% CI 1.08-3.21], p = 0.03) and availability of funding with being controlled (OR, 2.26 [95% CI 1.09-4.69], p = 0.03). Hospital beds (OR, 1.14 [95% CI 1.02-1.27], p = 0.02), nurses/midwives (OR, 1.24 [95% CI 1.06-1.44], p = 0.006), and physicians (OR, 1.21 [95% CI 1.11-1.32], p < 0.001) per 1,000 people were positively associated with being diagnosed and, similarly, with being treated; and the number of physicians was additionally associated with being controlled (OR, 1.12 [95% CI 1.01-1.23], p = 0.03). For diabetes, no positive associations were seen between NCD readiness indicators and outcomes. There was no association between country development, health service finance, or health service performance and readiness indicators and any outcome, apart from GDP (OR, 1.70 [95% CI 1.12-2.59], p = 0.01), HDI (OR, 1.21 [95% CI 1.01-1.44], p = 0.04), and number of physicians per 1,000 people (OR, 1.28 [95% CI 1.09-1.51], p = 0.003), which were associated with being diagnosed. Six countries had data on cascades of care and nationwide-level data on facility preparedness. Of the 27 associations tested between facility preparedness indicators and outcomes, the only association that was significant was having metformin available, which was positively associated with treatment (OR, 1.35 [95% CI 1.01-1.81], p = 0.04). The main limitation was use of blood pressure measurement on a single occasion to diagnose hypertension and a single blood glucose measurement to diagnose diabetes. Conclusion In this study, we observed that indicators of country preparedness to deal with CVDRFs are poor proxies for quality clinical care received by patients for hypertension and diabetes. The major implication is that assessments of countries' preparedness to manage CVDRFs should not rely on proxies; rather, it should involve direct assessment of quality clinical care., Author(s): Justine I. Davies 1,2,3,4,*, Sumithra Krishnamurthy Reddiar 5, Lisa R. Hirschhorn 6, Cara Ebert 7, Maja-Emilia Marcus 8, Jacqueline A. Seiglie 9, Zhaxybay Zhumadilov 10, Adil Supiyev 11, Lela [...]

Differences in phenological responses to climate change among species can desynchronise ecological interactions and thereby threaten ecosystem function. To assess these threats, we must quantify the relative impact of climate change on species at different trophic levels. Here, we apply a Climate Sensitivity Profile approach to 10,003 terrestrial and aquatic phenological data sets, spatially matched to temperature and precipitation data, to quantify variation in climate sensitivity. The direction, magnitude and timing of climate sensitivity varied markedly among organisms within taxonomic and trophic groups. Despite this variability, we detected systematic variation in the direction and magnitude of phenological climate sensitivity. Secondary consumers showed consistently lower climate sensitivity than other groups. We used mid-century climate change projections to estimate that the timing of phenological events could change more for primary consumers than for species in other trophic levels (6.2 versus 2.5-2.9 days earlier on average), with substantial taxonomic variation (1.1-14.8 days earlier on average)., Numerous long-term ecological changes have been attributed to climate change (1). Shifts in the seasonal timing of recurring biological events such as reproduction and migration (that is, phenological changes) have [...]

This article examines the negotiation of security in landmark peace agreements brokered in Sudan (2002-2005) and Kenya (2008). It reviews the dominant literature on peace agreements, arguing that preoccupation with [...]

Background The prevalence of diabetes is increasing rapidly in low- and middle-income countries (LMICs), urgently requiring detailed evidence to guide the response of health systems to this epidemic. In an effort to understand at what step in the diabetes care continuum individuals are lost to care, and how this varies between countries and population groups, this study examined health system performance for diabetes among adults in 28 LMICs using a cascade of care approach. Methods and findings We pooled individual participant data from nationally representative surveys done between 2008 and 2016 in 28 LMICs. Diabetes was defined as fasting plasma glucose [greater than or equal to] 7.0 mmol/l (126 mg/dl), random plasma glucose [greater than or equal to] 11.1 mmol/l (200 mg/dl), HbA1c [greater than or equal to] 6.5%, or reporting to be taking medication for diabetes. Stages of the care cascade were as follows: tested, diagnosed, lifestyle advice and/or medication given ('treated'), and controlled (HbA1c < 8.0% or equivalent). We stratified cascades of care by country, geographic region, World Bank income group, and individual-level characteristics (age, sex, educational attainment, household wealth quintile, and body mass index [BMI]). We then used logistic regression models with country-level fixed effects to evaluate predictors of (1) testing, (2) treatment, and (3) control. The final sample included 847,413 adults in 28 LMICs (8 low income, 9 lower-middle income, 11 upper-middle income). Survey sample size ranged from 824 in Guyana to 750,451 in India. The prevalence of diabetes was 8.8% (95% CI: 8.2%-9.5%), and the prevalence of undiagnosed diabetes was 4.8% (95% CI: 4.5%-5.2%). Health system performance for management of diabetes showed large losses to care at the stage of being tested, and low rates of diabetes control. Total unmet need for diabetes care (defined as the sum of those not tested, tested but undiagnosed, diagnosed but untreated, and treated but with diabetes not controlled) was 77.0% (95% CI: 74.9%-78.9%). Performance along the care cascade was significantly better in upper-middle income countries, but across all World Bank income groups, only half of participants with diabetes who were tested achieved diabetes control. Greater age, educational attainment, and BMI were associated with higher odds of being tested, being treated, and achieving control. The limitations of this study included the use of a single glucose measurement to assess diabetes, differences in the approach to wealth measurement across surveys, and variation in the date of the surveys. Conclusions The study uncovered poor management of diabetes along the care cascade, indicating large unmet need for diabetes care across 28 LMICs. Performance across the care cascade varied by World Bank income group and individual-level characteristics, particularly age, educational attainment, and BMI. This policy-relevant analysis can inform country-specific interventions and offers a baseline by which future progress can be measured., Author(s): Jennifer Manne-Goehler 1,*, Pascal Geldsetzer 2, Kokou Agoudavi 3, Glennis Andall-Brereton 4, Krishna K. Aryal 5, Brice Wilfried Bicaba 6, Pascal Bovet 7,8, Garry Brian 9, Maria Dorobantu 10, [...]

Longitudinal research has demonstrated that social outcomes for adults with autism are restricted, particularly in terms of employment and living arrangements. However, understanding of individual and environmental factors that influence these outcomes is far from complete. This longitudinal study followed a community sample of children and adolescents with autism into adulthood. Social outcomes in relation to community inclusion and living skills were examined, including the predictive role of a range of individual factors and the environment (socioeconomic disadvantage). Overall, the degree of community inclusion and living skills was restricted for the majority, and while childhood IQ was an important determinant of these outcomes, it was not the sole predictor. The implications of these findings in relation to interventions are discussed. Keywords Autism * Community inclusion * Living skills Adult outcomes, Introduction Studies of adult outcomes in autism have focused on broad constructs of outcome, typically including evaluations of social functioning in terms of independence, social relationships, employment status, and living [...]

1. INFORMATION FROM THE EuCheMS DIVISION OF ANALYTICAL CHEMISTRY (DAC) Euroanalysis XVII, held in Warsaw, Poland, August 25-29, was the prime event within the DAC portfolio of activities for 2013. [...]

Key theories of autism implicate orbitofrontal cortex (OFC) compromise, while olfactory identification (OI) deficits are associated with OFC dysfunction. This study aimed to complete a 5-year follow-up of children with high-functioning autism (HFA) who previously lacked the normal age-OI association; and compare unirhinal-OI in children with HFA, Asperger's disorder (ASP), and controls. While both HFA and controls had improved birhinal-OI at follow-up, reduced OI in some HFA participants suggested OFC deterioration and heterogeneous OFC development. Unirhinal-OI was impaired in HFA but not ASP relative to controls, suggesting orbitofrontal compromise in HFA but integrity in ASP. Differing IQ-OI relationships existed between HFA and ASP. Findings support the hypothesis of separate neurobiological underpinnings in ASP and HFA, specifically differential orbitofrontal functioning. Keywords High-functioning autism * Asperger's disorder * Olfactory identification * UPSIT, Autistic disorder (autism) and Asperger's disorder (ASP) are neurodevelopmental disorders with lifelong impact, yet underlying neurobiological abnormalities are poorly understood. Clarifying neural underpinnings could improve early diagnosis, allow the development [...]

A new approach for process monitoring is described, the self-organizing map quality control (SOMQC) index. The basis of the method is that SOM maps are formed from normal operating condition (NOC) samples, using a leave-one-out approach. The distances (or dissimilarities) of the left out sample can be determined to all the units in the map, and the nth percentile measured distance of the left out sample is used to provide a null distribution of NOC distances which is generated using the Hodges--Lehmann method. The nth percentile distance of a test sample to a map generated from all NOC samples can be measured and compared to the null distribution at a given confidence level to determine whether the sample can be judged as out of control. The approach described in this paper is applied to online high-performance liquid chromatography (HPLC) measurements of a continuous pharmaceutical process and is compared to other established methods including Q and D statistics and support vector domain description. The SOMQC has advantages in that there is no requirement for multinormality in the NOC samples, or for linear models, or to perform principal components analysis (PCA) prior to the analysis with concomitant issues about choosing the number of PCs. It also provides information about which variables are important using component planes. The influence of extreme values in the background data set can also be tuned by choosing the distance percentile. 10.1021/ac100383g

The article describes the extension of the self organizing maps discrimination index (SOMDI) for cases where there are more than two classes and more than one factor that may influence the group of samples by using supervised SOMs to determine which variables and how many are responsible for the different types of separation. The methods are illustrated by an application in the area of metabolic profiling, consisting of a nuclear magnetic resonance (NMR) data set of 96 samples of human saliva, which is characterized by three factors, namely, whether the sample has been treated or not, 16 donors, and 3 sampling days, differing for each donor. The sampling days can be considered a null factor as they should have no significant influence on the metabolic profile. Methods for supervised SOMs involve including a classifier for organizing the map, and we report a method for optimizing this by using an additional weight that determines the relative importance of the classifier relative to the overall experimental data set in order to avoid overfitting. Supervised SOMs can be obtained for each of the three factors, and we develop a multiclass SOM discrimination index (SOMDI) to determine which variables (or regions of the NMR spectra) are considered significant for each of the three potential factors. By dividing the data itera. lively into training and test sets 100 times, we define variables as significant for a given factor if they have a positive SOMDI in the training set for the factor and class of interest over all iterations. 10.1021/ac9020566

The paper discusses variable selection as used in large metabolomic studies, exemplified by mouse urinary gas chromatography of 441 mice in three experiments to detect the influence of age, diet, and stress on their chemosignal. Partial least squares diacriminant analysis (PLS-DA) was applied to obtain class models, using a procedure of 20 000 iterations including the bootstrap for model optimization and random splits into test and training sets for validation. Variables are selected using PLS regression coefficients on the training set using an optimized number of components obtained from the bootstrap. The variables are ranked in order of significance, and the overall optimal variables are selected as those that appear as highly significant over 100 different test and training set splits. Cost/benefit analysis of performing the model on a reduced number of variables is also illustrated. This paper provides a strategy for properly validated methods for determining which variables are most significant for discriminating between two groups in large metabolomic data sets avoiding the common pitfall of overfitting if variables are selected on a combined training and test set and also taking into account that different variables may be selected each time the samples are split into training and test sets using iterative procedures.

The ESCRT (endosomal sorting complex required for transport) pathway is required for terminal membrane fission events in several important biological processes, including endosomal intraluminal vesicle formation(1,2), HIV budding' and cytokinesis [...]

The uncertainty, due to random noise, of the measurements made with a mixer-based nonlinear vector network analyzer are analyzed. An approximate covariance matrix corresponding to the measurements is derived that can be used for fitting models and maximizing the dynamic range in the measurement setup. The validity of the approximation is verified with measurements. Index Terms--Nonlinear systems, phase measurement, uncertainty.

The majority of works in metabolomics employ approaches based on principal components analysis (PCA) and partial least-squares, primarily to determine whether samples rail within large groups. However, analytical chemists rarely tackle the problem of individual fingerprinting, and in order to do this effectively, it is necessary to study a large number of small groups rather than a small number of large groups and different approaches are required, as described in this paper. Furthermore, many metabolomic studies on mammals and humans involve analyzing compounds (of peaks) that are present in only a certain portion of samples, and conventional approaches of PCA do not cope well with sparse matrices where there may be many Os. There is, however, a large number of qualitative similarity measures available for this purpose that can be exploited via principal coordinates analysis (PCO). It can be shown that PCA scores are a specific case of PCO scores, using a quantitative similarity measure. A large-scale study of human sweat consisting of nearly 1000 gas chromatography/mass spectrometry analyses from the sweat of an isolated population of 200 individuals in Carinthia (Southern Austria) sampled once per fortnight over 10 weeks was employed in this study and grouped into families. The first step was to produce a peak table requiring peak detection, alignment, and integration. Peaks were reduced from 5080 to 373 that occurred in at least i individual over 4 out of 5 fortnights. Both qualitative (presence/absence) and quantitative (equivalent to PCA) similarity measures can be computed. PCO and the Kolomorogov-Smirnoff (KS) rank test are applied to these similarity matrices. It is shown that for this data set there is a reproducible individual fingerprint, which is best represented using the qualitative similarity measure as assessed both by the Hotelling [t.sup.2] statistic as applied to PCO scores and the probabilities associated with the KS rank test.

We report here the characterization of the first agmatine/cadaverine aminopropyl transferase (ACAPT), the enzyme responsible for polyamine biosynthesis from an archaeon. The gene PF0127 encoding ACAPT in the hyperthermophile Pyrococcus furiosus was cloned and expressed in Escherichia coli, and the recombinant protein was purified to homogeneity. P. furiosus ACAPT is a homodimer of 65 kDa. The broad substrate specificity of the enzyme toward the amine acceptors is unique, as agmatine, 1,3-diaminopropane, putrescine, cadaverine, and sym-nor-spermidine all serve as substrates. While maximal catalytic activity was observed with cadaverine, agmatine was the preferred substrate on the basis of the [k.sub.cat]/[K.sub.m] value. P. furiosus ACAPT is thermoactive and thermostable with an apparent melting temperature of 108[degrees]C that increases to 112[degrees]C in the presence of cadaverine. Limited proteolysis indicated that the only proteolytic cleavage site is localized in the C-terminal region and that the C-terminal peptide is not necessary for the integrity of the active site. The crystal structure of the enzyme determined to 1.8-[angstrom] resolution confirmed its dimeric nature and provided insight into the proteolytic analyses as well as into mechanisms of thermal stability. Analysis of the polyamine content of P.furiosus showed that spermidine, cadaverine, and sym.nor-spermidine are the major components, with small amounts of sym-nor-spermine and N-(3-aminopropyl)cadaverine (APC). This is the first report in Archaea of an unusual polyamine APC that is proposed to play a role in stress adaptation.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jss.2006.07.009 Byline: Pearl Brereton (a), Barbara A. Kitchenham (a), David Budgen (b), Mark Turner (a), Mohamed Khalil (c) Keywords: Systematic literature review; Empirical software engineering Abstract: A consequence of the growing number of empirical studies in software engineering is the need to adopt systematic approaches to assessing and aggregating research outcomes in order to provide a balanced and objective summary of research evidence for a particular topic. The paper reports experiences with applying one such approach, the practice of systematic literature review, to the published studies relevant to topics within the software engineering domain. The systematic literature review process is summarised, a number of reviews being undertaken by the authors and others are described and some lessons about the applicability of this practice to software engineering are extracted. The basic systematic literature review process seems appropriate to software engineering and the preparation and validation of a review protocol in advance of a review activity is especially valuable. The paper highlights areas where some adaptation of the process to accommodate the domain-specific characteristics of software engineering is needed as well as areas where improvements to current software engineering infrastructure and practices would enhance its applicability. In particular, infrastructure support provided by software engineering indexing databases is inadequate. Also, the quality of abstracts is poor; it is usually not possible to judge the relevance of a study from a review of the abstract alone. Author Affiliation: (a) School of Computing and Mathematics, Keele University, Keele, Staffordshire ST5 5BG, UK (b) Department of Computer Science, Durham University, Durham, Science Laboratories, South Road, Durham City, DH1 3LE, UK (c) Department of Computer Sciences, University of Khartoum, P.O. Box 321, Khartoum, Sudan Article History: Received 7 March 2006; Revised 26 June 2006; Accepted 10 July 2006

Summary: This article reports on an exploratory research project to evaluate the usefulness or otherwise of real-time visual feedback in the singing studio. The primary purpose of the work was [...]

This report describes a rolling stir bar sampling procedure for volatile organic compounds (VOCs) present on various biological surfaces. In combination with thermal desorption/gas chromatography/mass spectrometry, this analytical technique was initially tested for quantitative profiling of human skin VOCs. It is also applicable to additional hydrophobic surfaces such as agricultural products, plant materials, and bird feathers. Use of embedded internal standards provides highly reproducible and quantitative results for a wide variety of sampled trace components. The samples of collected human skin VOCs and standards were found stable under cool storage conditions for at least 14 days, making this approach suitable for field biological and agricultural studies. Additionally, this methodology appears to have potential for forensic and toxicological investigations, as suggested through the analyses of VOC profiles of the human thumb prints recovered from a nonbiological smooth surface.

Advances in microwave instrumentation now make it feasible to accurately measure not only the magnitude spectrum, but also the phase spectrum of wide-bandwidth signals. In a practical measurement, the spectrum is measured over a finite window of time. The phase spectrum is related to the position of this window, causing the spectrum to differ between measurements of an identical waveform. It is difficult to compare multiple measurements with different window positions or to incorporate them into a model. Several methods have been proposed for determining the phase spectrum such that multiple measurements can be effectively compared and utilized in models. The methods are reviewed in terms of the information required to determine the phase and compared in terms of their robustness in the presence of measurement noise. Index Terms--Intermodulation distortion, measurement uncertainty, nonlinear systems, phase measurement.

0. INTRODUCTION In a familiar episode from the Brhadaranyaka Upanisad, as the sage Yajnavalkya is about to depart, he tells his wife Maitreyi that he wishes to divide his possessions [...]

The electron impact mass spectra of haloalkanes in superfluid helium droplets are discussed. Helium matrix impedes the channels requiring C-C bond fission or concentrates processes leading to the ejection of hydrogen halide molecules.

We present theory and simulations for a spectral narrowing scheme for laser diode arrays (LDAs) that employs optical feedback from a diffraction grating. We calculate the effect of the so-called smile of the LDA and show that it is possible to reduce the effect by using a cylindrical lens set at an angle to the beam. The scheme is implemented on a 19-element LDA with smile of 7.6 [micro]m and yields frequency narrowing from a free-running width of 2 to 0.15 nm. The experimental results are in good agreement with the theory. OCIS codes: 140.0140, 140.2010, 140.3300.

The VPS4 AAA ATPases function both in endosomal vesicle formation and in the budding of many enveloped RNA viruses, including HIV-1. VPS4 proteins act by binding and catalyzing release of the membrane-associated ESCRT-III protein lattice, thereby allowing multiple rounds of protein sorting and vesicle formation. Here, we report the solution structure of the N-terminal VPS4A microtubule interacting and transport (MIT) domain and demonstrate that the VPS4A MIT domain binds the C-terminal half of the ESCRT-III protein, CHMP1B ([K.sub.d] = 20 [+ or -] 13 [micro]M). The MIT domain forms an asymmetric three-helix bundle that resembles the first three helices in a tetratricopeptide repeat (TPR) motif. Unusual interhelical interactions are mediated by a series of conserved aromatic residues that form coiled-coil interactions between the second two helices and also pack against the conserved alanines that interdigitate between the first two helices. Mutational analyses revealed that a conserved leucine residue (Leu-64) on the third helix that would normally bind the fourth helix in an extended TPR is used to bind CHMP1B, raising the possibility that ESCRT-III proteins may bind by completing the TPR motif. HIV | budding | vacuolar protein sorting | multivesicular body | NMR

Detection and identification of impurities in pharmaceuticals is an essential task for determining the possible infringement of a patent. This article reports a multivariate analysis method to distinguish between tablets of the same substance on the basis of their origin, by characterizing route/process specific impurities via diagnostic ion chromatograms, using liquid chromatography/mass spectrometry (LC/MS). The approach is based on the formulation of a novel index that quantifies the similarity between LC/ MS samples, named the component detection weighted index of analogy. The index estimates similarity by fully exploiting the two-dimensional nature of the data, where the relative contribution of chromatograms relates to their quality and noise level. Results show that well-defined clusters are formed according to the origin of tablets; a series of ions are identified as characterizing each class and can be used to predict the origin of unknown tablet samples. The method presented is designed for analysis of larger data sets and can be suitable for exploratory analysis where any a priori knowledge on the data is scarce or absent, hence requiring the acquisition of chromatograms in a broad m/z range.

Results for a heterojunction bipolar transistor (HBT) are compared with those found using a vector network analyzer and a sophisticated extraction algorithm. The method is extended to simultaneously determine thermal resistance, R(sub TH), and to obtain a most precise estimate of emitter resistance.

Research has been conducted on dimethyl sulfoxide reductase from Rhodobacter capsulatus. The construction of the system used for expression site-directed mutants of this reductase in the natural host in order to generate and express dimethyl sulfoxide reductase with Y114F mutantion is described.