Optimisation of quantum Monte Carlo wave function: steepest descent method

We have employed the steepest descent method to optimise the variational ground state quantum Monte Carlo wave function for He, Li, Be, B and C atoms. We have used both the direct energy minimisation and the variance minimisation approaches. Our calculations show that in spite of receiving insufficient attention, the steepest descent method can successfully minimise the wave function. All the derivatives of the trial wave function respect to spatial coordinates and variational parameters have been computed analytically. Our ground state energies are in a very good agreement with those obtained with diffusion quantum Monte Carlo method (DMC) and the exact results.Comment: 13 pages, 3 eps figure

Microarray screening of Guillain-Barré syndrome sera for antibodies to glycolipid complexes

Objective: To characterize the patterns of autoantibodies to glycolipid complexes in a large cohort of Guillain-Barré syndrome (GBS) and control samples collected in Bangladesh using a newly developed microarray technique. Methods: Twelve commonly studied glycolipids and lipids, plus their 66 possible heteromeric complexes, totaling 78 antigens, were applied to polyvinylidene fluoride–coated slides using a microarray printer. Arrays were probed with 266 GBS and 579 control sera (2 μL per serum, diluted 1/50) and bound immunoglobulin G detected with secondary antibody. Scanned arrays were subjected to statistical analyses. Results: Measuring antibodies to single targets was 9% less sensitive than to heteromeric complex targets (49.2% vs 58.3%) without significantly affecting specificity (83.9%–85.0%). The optimal screening protocol for GBS sera comprised a panel of 10 glycolipids (4 single glycolipids GM1, GA1, GD1a, GQ1b, and their 6 heteromeric complexes), resulting in an overall assay sensitivity of 64.3% and specificity of 77.1%. Notable heteromeric targets were GM1:GD1a, GM1:GQ1b, and GA1:GD1a, in which exclusive binding to the complex was observed. Conclusions: Rationalizing the screening protocol to capture the enormous diversity of glycolipid complexes can be achieved by miniaturizing the screening platform to a microarray platform, and applying simple bioinformatics to determine optimal sensitivity and specificity of the targets. Glycolipid complexes are an important category of glycolipid antigens in autoimmune neuropathy cases that require specific analytical and bioinformatics methods for optimal detection

Artificial leaf device for hydrogen generation from immobilised C. reinhardtii microalgae

We developed a fully biomimetic leaf-like device for hydrogen production which allows incorporated fabric-immobilised microalgae culture to be simultaneously hydrated with media and harvested from the produced hydrogen in a continuous flow regime without the need to replace the algal culture. Our leaf device produces hydrogen by direct photolysis of water resulting from redirecting the photosynthetic pathways in immobilised microalgae due to the lack of oxygen. In contrast to the many other reports in the literature on batch photobioreactors producing hydrogen from suspension culture of microalgae, we present the first report where this is done in a continuous manner from a fabric-immobilised microalgae culture. The reported artificial leaf device maximises the sunlight energy utilisation per gram of algae and can be upscaled cheaply and easily to cover large areas. We compared the production of hydrogen from both immobilised and suspended cultures of C. reinhardtii microalgae under sulphur, phosphorus and oxygen deprived conditions. The viability and potential of this approach is clearly demonstrated. Even though this is a first prototype, the hydrogen yield of our artificial leaf device is twenty times higher per gram of algae than in previously the reported batch reactors. Such leaf-like devices could potentially be made from flexible plastic sheets and installed on roofs and other sun-exposed surfaces that are inaccessible by photovoltaic cells. The ability to continuously produce inexpensive hydrogen by positioning inexpensive sheets onto any surface could have an enormous importance in the field of biofuels. The proposed new concept can provide a cleaner and very inexpensive way of bio-hydrogen generation by flexible sheet-like devices

Penentuan Kawasan Agroindustri Berdasarkan Komoditas Unggulan Di Kabupaten Bondowoso

Sektor pertanian di Kabupaten Bondowoso merupakan sektor utama dan merupakan penyumbang PDRB terbesar. Selain itu, adanya arahan dari RTRW Jawa Timur tahun 2011 tentang kebijakan arahan SWP Jember (Cluster Jember-Bondowoso-Situbondo) sebagai kegiatan kawasan industri pertanian di Jawa Timur. Sehingga pertanian merupakan potensi utama dalam peningkatan perekonomian. Namun potensi ini belum mampu memberikan nilai tambah (added value) terhadap pengembangan Kabupaten Bondowoso. Tujuan penelitian adalah menentukan kawasan agroindustri di Kabupaten Bondowoso yang dilakukan dengan tiga tahapan analisis, yaitu menentukan komoditas unggulan di Kabupaten Bondowoso dengan menggunakan alat analisis Static Location Quotion (SLQ), Dinamic Location Quotion (DLQ) dan Shift Share Analysis (SSA), kedua menentukan tingkat pengaruh (bobot) faktor-faktor yang menentukan dalam penentuan kawasan agroindustri dengan menggunakan analisa AHP, ketiga menentukan alternatif kawasan agroindustri yang berbasis komoditas unggulan dengan menggunakan alat analisa teknik overlay. Berdasarkan hasil analisis maka diperoleh dua jenis komoditas unggulan, yaitu komoditas padi dan komoditas jagung. Kemudian untuk tingkat pengaruh (bobot) faktor penentu kawasan agroindustri yaitu faktor bahan baku yang memiliki pengaruh paling besar. Sedangkan faktor kelembagaan merupakan faktor yang memiliki pengaruh yang paling kecil. Adapun kecamatan yang terpilih sebagai alternatif utama kawasan agroindustri di Kabupaten Bondowoso adalah Kecamatan Tlogosari dan Bondowoso untuk komoditas padi, dan Kecamatan Wringin untuk komoditas jagung. Dengan adanya penentuan kawasan Agroindustri di Kabupaten Bondowoso ini, diharapkan adanya pengelolaan komoditas unggulanyang optimal bagi peningkatan nilai tambah

Changing Urbanization Patterns in US Lung Cancer Mortality, 1950–2007

This study examined disparities in lung cancer mortality rates among US men and women in metropolitan and non-metropolitan areas from 1950 through 2007. Annual age-adjusted mortality rates were calculated for men and women in metropolitan and non-metropolitan areas, and differences in mortality rates were tested for statistical significance. Log-linear regression was used to model annual rates of change in mortality over time, while Poisson regression was used to estimate relative risk after adjusting for age, sex, deprivation, and urbanization levels. Urbanization patterns in lung cancer mortality changed dramatically between 1950 and 2007. Compared to men in metropolitan areas, men aged 25–64 years in non-metropolitan areas had significantly lower lung cancer mortality rates from 1950 to 1977 and men aged ≥65 years in non-metropolitan areas had lower mortality rates from 1950 to 1985. Differentials began to reverse and widen by the mid-1980s for men and by the mid-1990s for younger women. In 2007, compared to their metropolitan counterparts, men aged 25–64 and ≥65 years in non-metropolitan areas had 49 and 19% higher lung cancer mortality and women aged 25–64 and ≥65 years in non-metropolitan areas had 32 and 4% higher lung cancer mortality, respectively. Although adjustment for deprivation levels reduced excess lung cancer mortality risk among those in non-metropolitan areas, significant rural–urban differences remained. Rural–urban patterns reversed because of faster and earlier reductions in lung cancer mortality among men and women in metropolitan areas. Temporal trends in rural–urban disparities in lung cancer mortality appear to be consistent with those in smoking

The inclusion of delirium in version 2 of the National Early Warning Score will substantially increase the alerts for escalating levels of care: findings from a retrospective database study of emergency medical admissions in two hospitals

YesBackground The National Early Warning Score (NEWS) is being replaced with NEWS2 which adds 3 points for new confusion or delirium. We estimated the impact of adding delirium on the number of medium/high level alerts that are triggers to escalate care. Methods Analysis of emergency medical admissions in two acute hospitals (York Hospital (YH) and Northern Lincolnshire and Goole NHS Foundation Trust hospitals (NH)) in England. Twenty per cent were randomly assigned to have delirium. Results The number of emergency admissions (YH: 35584; NH: 35795), mortality (YH: 5.7%; NH: 5.5%), index NEWS (YH: 2.5; NH: 2.1) and numbers of NEWS recorded (YH: 879193; NH: 884072) were similar in each hospital. The mean number of patients with medium level alerts per day increased from 55.3 (NEWS) to 69.5 (NEWS2), a 25.7% increase in YH and 64.1 (NEWS) to 77.4 (NEWS2), a 20.7% increase in NH. The mean number of patients with high level alerts per day increased from 27.3 (NEWS) to 34.4 (NEWS2), a 26.0% increase in YH and 29.9 (NEWS) to 37.7 (NEWS2), a 26.1% increase in NH. Conclusions The addition of delirium in NEWS2 will have a substantial increase in medium and high level alerts in hospitalised emergency medical patients. Rigorous evaluation of NEWS2 is required before widespread implementation because the extent to which staff can cope with this increase without adverse consequences remains unknown

On optimum stratification

In this manuscript, we discuss the problem of determining the optimum stratification of a study (or main) variable based on the auxiliary variable that follows a uniform distribution. If the stratification of survey variable is made using the auxiliary variable it may lead to substantial gains in precision of the estimates. This problem is formulated as a Nonlinear Programming Problem (NLPP), which turn out to multistage decision problem and is solved using dynamic programming technique

Heterotic Vortex Strings

We determine the low-energy N=(0,2) worldsheet dynamics of vortex strings in a large class of non-Abelian N=1 supersymmetric gauge theories.Comment: 44 pages, 3 figures. v2: typos corrected, reference adde

Transverse Fivebranes in Matrix Theory

M-theory on the maximally supersymmetric plane wave background of eleven-dimensional supergravity admits spherical BPS transverse M5-branes with zero light-cone energy. We give direct evidence that the single M5-brane state corresponds to the trivial (X=0) classical vacuum in the large N limit of the plane wave matrix theory. In particular, we show that the linear fluctuation spectrum of the spherical fivebrane matches exactly with the set of exactly protected excited states about the X=0 vacuum in the matrix model. These states include geometrical fluctuations of the sphere, excitations of the worldvolume two-form field, and fermion excitations. In addition, we propose a description of multiple fivebrane states in terms of matrix model vacua. Finally, we discuss how to obtain the continuum D2/M2 and NS5/M5 theories on spheres from the matrix model. The matrix model can be viewed as a regularization for these theories.Comment: Latex file, 2 eps figures, 22 pages; v2: typo correcte