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Effect of simultaneous Ga and Te addition on the structure of As 2 Se 3 glasses is studied using X-ray photoelectron spectroscopy (XPS), extended X-ray absorption fine structure (EXAFS) and Raman techniques. It is shown that most of As, Se and Te atoms build a covalent network according to their main valences. Three-fold coordinated As atoms form pyramidal structural units, which are connected via bridges of two-fold coordinated chalcogen atoms (Se, Te). On the other hand, coordination of Ga in glassy samples is found to be greater than three, as expected from its valence, increasing with Te content. Some of the As atoms appear to be converted into four-fold coordinated state at low Te concentration, while a fraction of Te and, possibly, Se atoms are thought to exist in a singly-coordinated (terminal) state in the vicinity of Ga in the samples with higher Te concentration. [ABSTRACT FROM AUTHOR]

Abstract: In this article we consider the problem of partitioning a signal sequence into a set of signal sub-sequences, in such a way that each sub-sequence can be adequately modeled by a superposition of different sinusoids. In our formulation, the number of sub-sequences, the points at which two adjacent sub-sequences join, as well as the sinusoid composition in each sub-sequence are assumed unknown. We recast this problem as a statistical model selection problem, and invoke the minimum description length principle to construct estimators for these unknowns. As to be shown, these estimators are defined as the joint optimizer of a relatively complex objective function, and a genetic algorithm is developed for solving the corresponding optimization problem. The empirical performance of the resulting partitioning procedure is evaluated by a set of numerical experiments. The procedure is also applied to aid solving a classification problem that involves earthquake and explosion data. [Copyright &y& Elsevier]

Abstract: This article studies the problem of estimating the self-similarity parameter of network traffic traces. A robust wavelet-based procedure is proposed for this estimation task of deriving estimates that are less sensitive to some commonly encountered non-stationary traffic conditions, such as sudden level shifts and breaks. Two main ingredients of the proposed procedure are: (i) the application of a robust regression technique for estimating the parameter from the wavelet coefficients of the traces, and (ii) the proposal of an automatic level shift removal algorithm for removing sudden jumps in the traces. Simulation experiments are conducted to compare the proposed estimator with existing wavelet-based estimators. The proposed estimator is also applied to real traces obtained from the Abilene Backbone Network and a university campus network. Both results from simulated experiments and real trace applications suggest that the proposed estimator is superior. [Copyright &y& Elsevier]

The oral microbiome is altered in the presence of oral squamous cell carcinoma (OSCC). It is unknown if clinical outcomes, such as disease specific survival (DSS), are associated with differences in the abundance of select bacterial genera. The aim of this study is to determine if there are microbiome differences based on DSS in OSCC using The Cancer Microbiome Atlas (TCMA) and an in-tandem analysis of a prospectively collected database. TCMA is a publicly available database containing curated, decontaminated microbial profiles for tumors from 1,772 patients. Data utilized from this database was limited to microbiome profiles and clinicopathologic features for OSCC patients. Separately, our institution collects oral swab samples from OSCC tumors prior to surgical treatment for 16S rRNA sequencing and follows outcomes prospectively. Statistical analysis was performed using R Studio. Predictor variables for DSS were analyzed using logistic regression models reported with hazard ratio (HR) and 95% confidence interval (CI). R Studio was used to plot Beta Diversity and PCoA using Vegan package, and the Wilcoxon signed-rank and Kruskal-Wallis test were performed to evaluate differential abundance between the bacterial genera. Statistical significance was defined as p<0.05. One hundred five patients with OSCC were included from TCMA with a mean age of 60 (std 13, min 19, max 90), 65% male (N=68) and 92% white (N=95) with diverse oral cavity primary sites with oral tongue most common (N=55, 52%). Twenty-eight (26%) were Stage I-II and 77 (74%) were Stage III-IVA. There were no patients with distant metastases. Rates of lymphovascular invasion (LVI) were 23% (N=18), perineural invasion (PNI) were 56% (N=47) and microscopic or gross extranodal extension (ENE) were 26% (N=20). Negative surgical margins occurred in 83 patients (84%), and the majority had no prior cancer diagnosis (N=100, 95%). Forty-one patients (59%) were disease free with a mean follow up of 35 months (std 31, min 2.2 months, max 173 months). Clinicopathologic features that were predictive of DSS included ENE (HR 2.73, 95% CI 1.18, 6.34, p=0.019) and being a current smoker (HR 3.12, 95% CI 1.08, 9.04, p=0.036). There were 40 bacterial genera identified in TCMA for OSCC tumors. No difference was observed in beta diversity between patients with recurrence versus no recurrence. Examining relative abundance of bacterial genera revealed that Leptotrichia (p=0.023) and Haemophilus (p=0.045) were differentially enriched based on DSS. Preliminary analysis of a prospectively collected database of OSCC microbiome oral swab samples also showed that changes in the relative abundance of Leptotrichia (p=0.00002) and Haemophilus (p=0.00023) were associated with recurrence. Changes in the relative abundance of select oral bacteria genera are associated with recurrent OSCC. Shifts in the microbiome are seen prior to surgical treatment and may be predictive of clinical outcomes. [ABSTRACT FROM AUTHOR]

Background: The benefits of physical activity (PA) for children with disabilities are well documented, and children with physical disabilities (PD) are often less active than peers with other disability types. Various correlates associated with PA in children with PD have been identified in separate studies, and a thorough analysis of these correlates could aid in understanding and designing interventions that promote children with PD to be more physically active. The purpose of this systematic review was to provide a comprehensive summary of the correlates of PA in children with PD.Method: A systematic search using PubMed, CINAHL, Cochrane Library, PsychINFO, Eric, and EMbase was initiated in October 2014 to identify studies examining the correlates of PA in children with PD aged 6-18years. Two researchers independently screened studies, assessed their methodological quality, and extracted relevant data. The correlates were synthesized and further assessed semi-quantitatively.Results: A total of 45 articles were included in the detailed review. Several modifiable physical, psychological, and environmental correlates were consistently and positively associated with PA in children with PD. Some non-modifiable correlates (e.g., intellectual ability, parents' ethnicity) were found to be consistently and negatively associated with PA.Conclusions: The correlates of PA in children with PD are multifaceted and along many dimensions. This review can have implications for future studies and these may confirm the consistency of variables related to PA. Insights derived from the outcomes may also foster the measurement of the magnitude of associations that could assist the development of future interventions. [ABSTRACT FROM AUTHOR]

Abstract: PPT1-related neuronal ceroid lipofuscinosis (NCL) is a lysosomal storage disorder caused by deficiency in a soluble lysosomal enzyme, palmitoyl-protein thioesterase-1 (PPT1). Enzyme replacement therapy (ERT) has not been previously examined in a preclinical animal model. Homozygous PPT1 knockout mice reproduce the known features of the disease, developing signs of motor dysfunction at 5months of age and death by around 8months. In the current study, PPT1 knockout mice were treated with purified recombinant PPT1 (0.3mg, corresponding to 12mg/kg or 180 U/kg for a 25g mouse) administered intravenously weekly either 1) from birth; or 2) beginning at 8weeks of age. The treatment was surprisingly well tolerated and neither anaphylaxis nor antibody formation was observed. In mice treated from birth, survival increased from 236 to 271days (p<0.001) and the onset of motor deterioration was similarly delayed. In mice treated beginning at 8weeks, no increases in survival or motor performance were seen. An improvement in neuropathology in the thalamus was seen at 3months in mice treated from birth, and although this improvement persisted it was attenuated by 7months. Outside the central nervous system, substantial clearance of autofluorescent storage material in many tissues was observed. Macrophages in spleen, liver and intestine were especially markedly improved, as were acinar cells of the pancreas and tubular cells of the kidney. These findings suggest that ERT may be an option for addressing visceral storage as part of a comprehensive approach to PPT1-related NCL, but more effective delivery methods to target the brain are needed. [Copyright &y& Elsevier]

The complete 64 508 bp nucleotide sequence of the IncP-1β antibiotic-resistance plasmid pB10, which was isolated from a waste-water treatment plant in Germany and mediates resistance against the antimicrobial agents amoxicillin, streptomycin, sulfonamides and tetracycline and against mercury ions, was determined and analysed. A typical class 1 integron with completely conserved 5' and 3' segments is inserted between the tra and trb regions. The two mobile gene cassettes of this integron encode a β-Iactamase of the oxacillin-hydrolysing type (Oxa-2) and a gene product of unknown function (OrfE-like), respectively. The pB10-specific gene load present between the replication module (trfA1) and the origin of vegetative replication (oriV) is composed of four class II (Tn3 family) transposable elements: (i) a Tn501-like mercury-resistance (mer) transposon downstream of the trfA1 gene, (ii) a truncated derivative of the widespread streptomycin-resistance transposon Tn5393c, (iii) the insertion sequence element IS 1071 and (iv) a Tn 1721-like transposon that contains the tetracycline-resistance genes tetA and tetR. A very similar Tn501-like mer transposon is present in the same target site of the IncP-1β degradative plasmid pJP4 and the IncP-1β resistance plasmid R906, suggesting that pB10, R906 and pJP4 are derivatives of a common ancestor. Interestingly, large parts of the predicted pB10 restriction map, except for the tetracycline-resistance determinant, are identical to that of R906. It thus appears that plasmid pB10 acquired as many as five resistance genes via three transposons and one integron, which it may rapidly spread among bacterial populations given its high promiscuity. Comparison of the pB10 backbone DNA sequences with those of other sequenced IncP-1β plasmids reveals a mosaic structure. While the conjugative transfer modules (trb and tra regions) and the replication module are very closely related to the corresponding segments of the IncP-1β resistance plasmid R751 and even more similar to the IncP-1β degradative plasmids pTSA and pADP-1, the stable inheritance operons klcAB-korC and kleAEF are most similar to those of the IncP-1β resistance plasmid pB4, and clearly less similar to the other IncP-1β plasmids. This suggests that IncP-1β plasmids can undergo recombination in the environment, which may enhance plasmid diversity and bacterial adaptability. [ABSTRACT FROM AUTHOR]

This review considers the influence of selection pressure, fitness and population structures on the evolution of mobile genetic elements (including plasmids, phage, pathogenicity islands, transposons and insertion sequences) that constitute the horizontal gene pool of bacteria. These are considered at different scales using examples from in vitro evolutionary studies of Escherichia coli and associated bacteriophage, detailed molecular analyses of the broad host-range IncP-1 plasmids, population surveys of pseudomonad plasmids and genomic comparisons of members of the Rhizobiaceae. All biological systems show genetic redundancy (the existence of allelic variation) at some population level, i.e. within a cell, a clone, population or community. We consider the level(s) at which redundancy is expressed and how this will affect and has influenced the evolution of mobile genetic elements. [Copyright &y& Elsevier]