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This study investigated the effect of low DO operation on the performance of membrane bioreactors (MBRs) in treating wastewater with low carbon to nitrogen ratios(C/N = 3.5), the microbiological communities in them, and on membrane fouling. Two bench-scale MBRs were operated in tandem under different DO regimes: one maintained at an average DO of 0.5 mg/L and the other at 2 mg/L. Both systems exhibited high organic carbon removal efficiencies above 97%, with the low-DO reactor demonstrating a slight advantage. While the low DO conditions limited nitrification due to oxygen depletion affecting nitrifying bacteria, these conditions favored improved total nitrogen removal by achieving simultaneous nitrification and denitrification (SND) process. This improvement is attributed to the facilitation of denitrification and other nitrogen transformations, including the anammox and comammox pathways. Furthermore, the low DO environment was associated with reduced membrane fouling rates, suggesting that reduced aeration does not compromise membrane fouling mitigation. Microbial community analysis revealed that lower DO concentrations significantly increased diversity, as evidenced by alpha and beta diversity metrics. Redanduncy Analysis (RDA) confirmed the proliferation of nitrogen-transforming bacteria under low DO conditions, and the detection of anammox and comammox bacteria in the sludge samples confirmed the operation of these alternative nitrogen removal pathways. [ABSTRACT FROM AUTHOR]

Autism spectrum disorder (ASD) is a developmental disorder underdiagnosed in adults. To date, no consistent evidence of alterations in brain structure has been reported in adults with ASD and few studies were conducted at that age. We analyzed structural magnetic resonance imaging data from 167 high functioning adults with ASD and 195 controls. We ran our analyses on a discovery (n = 301) and a replication sample (n = 61). The right caudal anterior cingulate cortical thickness was significantly thinner in adults with ASD compared to controls in both the discovery and the replication sample. Our work underlines the relevance of studying the brain anatomy of an adult ASD population. [ABSTRACT FROM AUTHOR]

Attention Deficit and Hyperactive Disorder (ADHD) and Autism Spectrum Disorders (ASD) are frequent comorbid neurodevelopmental conditions and the overlap between both disorders remains to be delineated. A more complete understanding of the shared genetic and environmental factors is needed. Using a family-based method, we evaluated the risk of ADHD in a group of relatives with an ASD proband (ASD−) and a group of relatives with an ASD and ADHD proband (ASD+). We enrolled 1245 individuals in the study: 499 probands, their 746 first-degree relatives and 140 controls. We used a multivariate generalized estimating equation (GEE) model, in which the dependent variable was the ADHD diagnosis in the relatives and the independent variable the ASD+ or ASD− in probands. We adjusted for sociodemographic factors (age, sex, IQ) and for the nature of the familial relationship with the affected proband (parent or sibling). Among the probands, there were 287 ASD− and 212 ASD+ individuals. ADHD was more frequent in relatives (19%) than in the control group (7%) (p = 0.001). The risk of ADHD was higher in the ASD+ relatives group than in the ASD− relatives group (GEE model OR 1.58 [95% CI 1.04-2.38], p = 0.032). This result was found in parents (OR 1.96 [95% CI  1.14-3.36], but not in siblings (OR 1.28 [95% CI 0.84-1.94], p = 0.434). Our study provides a representative estimate of the family distribution of ADHD in relatives of ASD probands but supports the modest effect of shared genetic and environmental factors between both disorders. [ABSTRACT FROM AUTHOR]

The objectives of this study were to evaluate the effects of supplementing maize meal and soybean meal, separately or mixed, on egg production performance of two breeds of scavenging hens under on-farm conditions. Treatments were: (1) confined, with a mixed feed (75% maize meal and 25% soybean meal) ad libitum (CMF); (2) scavenging, with a supplement of 60 g/bird per day of maize meal (ScM); (3) scavenging, with a supplement of 25 g/bird per day of soybean meal (ScS); (4) scavenging, with 54 g/bird per day of the mixed feed (ScMF). Mean hen-day production was 21.8%, 19.8%, 17.7% and 22.8% for the CMF, ScM, ScS and ScMF treatments, respectively ( p<0.05), and was significantly ( p<0.001) higher for the improved Tamhoang breed (24.4%) than for the local Ri hens (16.7%). Mean egg weight was significantly higher for the Tamhoang (53.2 g) compared to the Ri hens (45.0 g) ( p<0.01). Feed consumption per kilogram of eggs was significantly higher for the CMF treatment compared to the other treatments and was lower for the ScS compared to the other scavenging treatments ( p<0.05). Feed cost per kilogram of eggs was lowest for the ScM treatment and was 30 to 40% higher for the confined treatment compared to the scavenging treatments. Feed consumption and cost of feed per kilogram of eggs were significantly lower for the Tamhoang than for the Ri hens. [ABSTRACT FROM AUTHOR]

Numerical grid generation techniques play an important role in the numerical solution of partial differential equations on arbitrarily shaped regions. For coastal ocean modeling, in particular, a one-block grid covering the region under study is commonly used. Most bodies of water of interest have complicated coastlines; e.g., the Persian Gulf and Mediterranean Sea. Since such one-block grids are not boundary conforming, the number of unused grid points can be a relatively large portion of the entire domain space. Other disadvantages of using a one block grid include large memory requirements and long computer processing time. Multiblock grid generation and dual-level parallel techniques are used to overcome these problems. Message Passing Interface (MPI) is used to parallelize the Multiblock Grid Princeton Ocean Model (MGPOM) such that each grid block is assigned to a unique processor. Since not all grid blocks are of the same size, the workload varies between MPI processes. To alleviate this, OpenMP dynamic threading is used to improve load balance. Performance results from the MGPOM model on a one-block grid, a twenty block grid, and a forty-two block grid after a 90-day simulation for the Persian Gulf demonstrate the efficacy of the dual-level parallel code version. [ABSTRACT FROM AUTHOR]

A coupled model of air-wave-sea interaction is modified based on a new roughness formulation and the latest data. The model parameters for aerodynamic roughness from below (ARB) and wave-dependent roughness from above (ARA, z0 a) are assumed equal. The combined roughness is assumed to be a function of friction velocity, gravity, air and seawater densities, and wave age ( c w). The model is used in a study of wave-enhanced turbulence under breaking waves to predict turbulent dissipation (ε), ARA, and drag coefficient ( C d). Both waves and shear production are considered as sources of ocean turbulent energy. The atmospheric part of the model is used only to specify a correct condition at the interface. Numerical experiments are performed to study the ε-distribution, z0 a and C d, and to compare with data. The major achievement is model verification using all available data. The first full application of this model is in conjunction with an ocean circulation model in a coupled circulation-wave system. Simulations show that the ε-distribution is strongly dependent on local wind-forced wave heights. For each wind and wave state there is a particular wave-dependent depth that is verified by data. The comparison shows that the model predicted ε agrees well with the observed ε of the z−4 law distribution of Gargett (1989). Simulations also show that waves have an important role in causing ε to differ from the classical wall-layer theory and z0 a, with a value of 0.30 for the empirical constant a a. The model-predicted ε, z0 a, C d and C gd agree well with data. [ABSTRACT FROM AUTHOR]

A coastal ocean σ-coordinate model of Monterey Bay (MOB) with realistic bottom topography and coastlines is developed using the Princeton Ocean Model (POM) and grid generation technique (GGT) to study the horizontal pressure gradient errors associated with the MOB steep topography. The submarine canyon in MOB features some of the steepest topography encountered anywhere in the world oceans. The MOB grids are designed using the EAGEAL View and GENIE++ grid generation systems. A grid package developed by Ly and Luong (1993) is used in this study to couple grids to the model. The MOB model is tested with both orthogonal and curvilinear nearly-orthogonal (CNO) grids. The CNO grid has horizontal resolution which varies from 300 m to 2 km, while the resolution of the orthogonal grid is uniform with δ x = 1.25 km and δ y = 1.38 km. These grids cover a domain of 180 × 160 km with the same number of grid points of 131 × 131. Vertical resolutions of 25, 35 and 45 vertical sigma levels are tested. The error in the MOB are evaluated in terms of mean kinetic energy and velocity against various grids, vertical, horizontal resolution and σdistributions, and bottom topography smoothing. Simulations with various grids show that GGT can be used as another tool in reducing σ-coordinate errors in coastal ocean modeling besides increasing resolution and smoothing bottom topography. Topographical smoothing not only reduces topographic slope, but changes realistic topography. A CNO grid with a high grid density packed along steep slopes and Monterey Submarine Canyon reduces the errors by 40% compared to a rectangular grid with the same number of grid points. The CNO grid is more efficient than the rectangular grid, since it has most of its grids over water. The simulations show that the presented MOB σ-coordinate model can be used with a confidence regarding horizontal pressure gradient error. [ABSTRACT FROM AUTHOR]