Метод коррекции для параллелизации численных моделей гидродинамики водоемов со свободной поверхностью

В роботi запропоновано метод перетворення послiдовних алгоритмiв моделей гiдродинамiки резервуарiв з вiльною поверхнею в паралельнi, використовуючи MPI та розбивку розрахункової областi на пiдобластi, перевагою якого є відносна простота реалізації, обумовлена потребою тільки у додаткових процедурах корекції замість значних перетворень існуючих програм послідовного розрахунку. Дослiджується вплив рiзноманiтних факторiв на ефективнiсть методу в термінах зменшення тривалості розрахунків зі збільшенням числа застосованих процесорів.В работе предложен метод преобразования последовательных алгоритмов моделей гидродинамики резервуаров со свободной поверхностью в параллельные, используя MPI и разбивку расчётной области на подобласти, преимуществом метода является относительная простота реализации, обусловленная потребностью только в дополнительных процедурах коррекции вместо значительных преобразований существующих программ последовательного расчёта. Исследуется влияние различных факторов на эффективность метода в терминах уменьшения длительности параллельных расчётов с увеличением числа используемых процессоров.This paper proposes a technique using MPI and domain decomposition to transform serial algorithms of numerical models for hydrodynamics simulations in the water reservoirs with free surface into parallel algorithms. The advantage of the proposed technique is a comparatively simple realization due to the necessity of only additional correction procedures instead of significant transformations of existing serial program code. The impacts of various factors on the method of efficiency are studied in terms of the speedup of computations with the increase of number of utilized processors

Borstvoeding in Nederland

In dit artikel wordt een overzicht gegeven over borstvoeding in Nederland, de determinanten van het starten en continueren van borstvoeding, en de mogelijkheden ter bevordering en ondersteuning van borstvoeding. In Nederland krijgt slechts een minderheid van de zuigelingen zes maanden borstvoeding volgens de aanbeveling van de WHO. Aanzienlijke gezondheidswinst is nog te boeken door een toename van de duur. Kennis van determinanten is belangrijk voor het ontwikkelen van effective interventies om borstvoeding te bevorderen. Nederlandse interventieonderzoeken laten geen grote effecten op de duur van de borstvoeding zien. Verbetering van de kwaliteit van zorg vergt een goede ketenzorg. Het is wenselijk nieuwe programma's te ontwikkelen gebaseerd op bekende determinanten van borstvoeding en andere benaderingen te ontwikkelen en onderzoeken. Monitoring en een goede evaluatie van de resultaten van deze programma's zijn een vereiste

III-V on-silicon sources for optical interconnect applications

Optical interconnects require efficient and flexible optical sources. This paper presents results on two technology platforms being developed for realizing these. Integration using wafer bonding technologies is well established now and the focus is on new device types including tunable lasers, multi-wavelength lasers and switching. As an alternative, we also started work on monolithic integration using heteroepitaxy directly on silicon. We here report recent results on low threshold nanowire lasers

Amylomaltase of Pyrobaculum aerophilum IM2 produces thermoreversible starch gels

Amylomaltases are 4-α-glucanotransferases (EC 2.4.1.25) of glycoside hydrolase family 77 that transfer α-1,4-linked glucans to another acceptor, which can be the 4-OH group of an α-1,4-linked glucan or glucose. The amylomaltase-encoding gene (PAE1209) from the hyperthermophilic archaeon Pyrobaculum aerophilum IM2 was cloned and expressed in Escherichia coli, and the gene product (PyAMase) was characterized. PyAMase displays optimal activity at pH 6.7 and 95°C and is the most thermostable amylomaltase described to date. The thermostability of PyAMase was reduced in the presence of 2 mM dithiothreitol, which agreed with the identification of two possible cysteine disulfide bridges in a three-dimensional model of PyAMase. The kinetics for the disproportionation of malto-oligosaccharides, inhibition by acarbose, and binding mode of the substrates in the active site were determined. Acting on gelatinized food-grade potato starch, PyAMase produced a thermoreversible starch product with gelatin-like properties. This thermoreversible gel has potential applications in the food industry. This is the first report on an archaeal amylomaltase

The oral microbiota of wild bears in Sweden reflects the history of antibiotic use by humans

Following the advent of industrial-scale antibiotic production in the 1940s,1 antimicrobial resistance (AMR) has been on the rise and now poses a major global health threat in terms of mortality, morbidity, and economic burden.2,3 Because AMR can be exchanged between humans, livestock, and wildlife, wild animals can be used as indicators of human-associated AMR contamination of the environment.4 However, AMR is a normal function of natural environments and is present in host-associated microbiomes, which makes it challenging to distinguish between anthropogenic and natural sources.4,5 One way to overcome this difficulty is to use historical samples that span the period from before the mass production of antibiotics to today. We used shotgun metagenomic sequencing of dental calculus, the calcified form of the oral microbial biofilm, to determine the abundance and repertoire of AMR genes in the oral microbiome of Swedish brown bears collected over the last 180 years. Our temporal metagenomics approach allowed us to establish a baseline of natural AMR in the pre-antibiotics era and to quantify a significant increase in total AMR load and diversity of AMR genes that is consistent with patterns of national human antibiotic use. We also demonstrated a significant decrease in total AMR load in bears in the last two decades, which coincides with Swedish strategies to mitigate AMR. Our study suggests that public health policies can be effective in limiting human-associated AMR contamination of the environment and wildlife

Force balance in canonical ensembles of static granular packings

We investigate the role of local force balance in the transition from a microcanonical ensemble of static granular packings, characterized by an invariant stress, to a canonical ensemble. Packings in two dimensions admit a reciprocal tiling, and a collective effect of force balance is that the area of this tiling is also invariant in a microcanonical ensemble. We present analytical relations between stress, tiling area and tiling area fluctuations, and show that a canonical ensemble can be characterized by an intensive thermodynamic parameter conjugate to one or the other. We test the equivalence of different ensembles through the first canonical simulations of the force network ensemble, a model system.Comment: 9 pages, 9 figures, submitted to JSTA

Gut colonization with methanobrevibacter smithii is associated with childhood weight development

OBJECTIVE: To prospectively investigate the presence and counts of archaea in feces of 472 children in association with weight development from 6 to 10 years of age. METHODS: Within the KOALA Birth Cohort Study, a single fecal sample from each child was analyzed by quantitative polymerase chain reaction to quantify archaea (Methanobrevibacter smithii, Methanosphera stadtmanae). Anthropometric outcomes (overweight [body mass index {BMI} >/= 85th percentile], age- and sex-standardized BMI, weight, and height z-scores) were repeatedly measured at ages (mean +/- SD) of 6.2 +/- 0.5, 6.8 +/- 0.5, 7.8 +/- 0.5, and 8.8 +/- 0.5 years. Generalized estimating equation was used for statistical analysis while controlling for confounders. RESULTS: Methanobrevibacter smithii colonization was associated with an increased risk of overweight (adjusted odds ratio [OR] = 2.69; 95% confidence interval [CI] 0.96-7.54) from 6 to 10 years of age. Children with high levels (>7 log10 copies/g feces) of this archaeon were at highest risk for overweight (OR = 3.27; 95% CI 1.09-9.83). Moreover, M. smithii colonization was associated with higher weight z-scores (adj. beta 0.18; 95% CI 0.00-0.36), but not with height. For BMI z-scores, the interaction (P = 0.008) between M. smithii and age was statistically significant, implying children colonized with M. smithii had increasing BMI z-scores with age. CONCLUSIONS: Presence and higher counts of M. smithii in the gut of children are associated with higher weight z-scores, higher BMI z-scores, and overweight

Early Life Antibiotic Exposure and Weight Development in Children

OBJECTIVE: To examine the timing, frequency, and type of antibiotic exposure during the first 10 years of life in association with (over)weight across this period in a cohort of 979 children. STUDY DESIGN: Within the Child, Parents and Health: Lifestyle and Genetic Constitution Birth Cohort Study, antibiotic exposure record was obtained from general practitioners. Anthropometric outcomes (age- and sex-standardized body mass index, weight and height z-scores, and overweight) were measured repeatedly at 7 time points during the first 10 years of life. Generalized estimating equations method was used for statistical analysis. RESULTS: After adjusting for confounding factors, children exposed to one course of antibiotics compared with none in the first 6 months of life had increased weight- (adjusted generalized estimating equations estimates [adjβ] 0.24; 95% CI 0.03-0.44) and height (adjβ 0.23; 95% CI 0.0002-0.46) z-scores; exposure to ≥2 courses during the second year of life was associated with both increased weight (adjβ 0.34; 95% CI 0.07-0.60), and height z-scores (adjβ 0.29; 95% CI -0.003 to 0.59). Exposure later in life was not associated with anthropometric outcomes. Associations with weight z-scores were mainly driven by exposure to broad- (≥2 courses: adjβ 0.11; 95% CI 0.003-0.22) and narrow-spectrum β-lactams (1 course: adjβ 0.18; 95% CI 0.005-0.35) during the follow-up period. Specific antibiotic used was not associated with body mass index z-scores and overweight. CONCLUSIONS: Repeated exposure to antibiotics early in life, especially β-lactam agents, is associated with increased weight and height. If causality of obesity can be established in future studies, this further highlights the need for restrictive antibiotic use and avoidance of prescriptions when there is minimal clinical benefit