bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural and antigenic characteristics of Campylobacter coli FlaA flagellin
Authors: Power M E , Guerry P , McCubbin W D , Kay C M , Trust T J
Published: November 2016

The polar flagellar filament of Campylobacter coli VC167 is composed of two highly related (98%) flagellin subunit proteins, FlaA and FlaB, whose antigenic specificities result from posttranslational modification. FlaA is the predominant flagellin species, and mutants expressing only FlaA form a full-length flagellar filament. Although the deduced M(r) of type 2 (T2) FlaA is 58,884 and the apparent M(r) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis is 59,500, the solution weight-average M(r) by sedimentation analysis was 63,000. Circular dichroism studies in the presence or absence of 0.1% sodium dodecyl sulfate or 50% trifluorethanol showed that the secondary structure of T2 FlaA flagellin was altered, with alpha-helix structure being increased to 25% in the nonpolar environment. The molecule also contained 35 to 48% beta-sheet and 11 to 29% beta-turn structure. Mimeotope analysis of octapeptides representing the sequence of FlaA together with immunoelectron microscopy and enzyme-linked immunosorbent assay with a panel of antisera indicated that many residues in presumed linear epitopes were inaccessible or nonepitopic in the assembled filament, with the majority being in the N-terminal 337 residues of the 572-residue flagellin. Residues at the carboxy-terminal end of the T2 FlaA subunit also become inaccessible upon assembly. Digestion with trypsin, chymotrypsin, and endoproteinase Glu-C revealed a protease-resistant domain with an approximate M(r) of 18,700 between residues 193 and 375. Digestion with endoproteinase Arg-C and endoproteinase Lys-C allowed the mapping of a segment of surface-exposed FlaA sequence which contributes serospecificity to the VC167 T2 flagellar filament at residues between 421 and 480.
Isolation and characterization of a generalized transducing phage for Xanthomonas campestris pv. campestris
Authors: Weiss B D , Capage M A , Kessel M , Benson S A
Published: November 2016

We have isolated and characterized a lytic double-stranded DNA Xanthomonas campestris pv. campestris bacteriophage (XTP1) capable of mediating generalized transduction. The phage transduces chromosomal markers at frequencies of 10(-5) to 10(-6) transductants per PFU. We demonstrated its genetic utility by the isolation and cotransduction of linked transposon insertions to a nonselectable locus, xgl, required for the cleavage of 5-bromo-3-chloro-indoyl-beta-D-galactoside and showed that rif and str alleles in X. campestris are 75% linked. One-step growth experiments showed that the latent and rise periods were each 2 h and the average burst size was 35. The DNA genome is approximately 180 kb, presumably modified in a sequence-specific manner, and may be covalently attached to protein(s). Electron micrographs show the phage particle to have an icosahedral head and contractile tail with tail fibers uniquely attached to a location 40 nm proximal from the end of the tail.
Pseudomonas aeruginosa 142 uses a three-component ortho-halobenzoate 1,2-dioxygenase for metabolism of 2,4-dichloro- and 2-chlorobenzoate
Authors: Romanov V , Hausinger R P
Published: November 2016

Cell extracts of Pseudomonas aeruginosa 142, which was previously isolated from a polychlorinated biphenyl-degrading consortium, were shown to degrade 2,4-dichlorobenzoate, 2-chlorobenzoate, and a variety of other substituted ortho-halobenzoates by a reaction that requires oxygen, NADH, Fe(II), and flavin adenine dinucleotide. By using extracts that were chromatographically depleted of chlorocatechol and catechol 1,2-dioxygenase activities, products of the initial reaction with 2,4- or 2,5-dichlorobenzoate and 2-chlorobenzoate were identified by mass spectrometry as 4-chlorocatechol and catechol. In contrast to the well-characterized benzoate dioxygenases or the recently described 2-halobenzoate 1,2-dioxygenase from P. cepacia 2CBS (S. Fetzner, R. Müller, and F. Lingens, J. Bacteriol. 174:279-290, 1992) that possess two protein components, the P. aeruginosa enzyme was resolved by ion-exchange chromatography into three components, each of which is required for activity. To verify the distinct nature of this enzyme, we purified, characterized, and identified one component as a ferredoxin (M(r), approximately 13,000) containing a single [2Fe-2S] Rieske-type cluster (electron paramagnetic resonance spectroscopic values of gx = 1.82, gy = 1.905, and gz = 2.02 in the reduced state) that is related in sequence to ferredoxins found in the naphthalene and biphenyl three-component dioxygenase systems. By analogy to these enzymes, we propose that the P. aeruginosa ferredoxin serves as an electron carrier between an NADH-dependent ferredoxin reductase and the terminal component of the ortho-halobenzoate 1,2-dioxygenase. The broad specificity and high regiospecificity of the enzyme make it a promising candidate for use in the degradation of mixtures of chlorobenzoates.
Gene cluster controlling conversion to alginate-overproducing phenotype in Pseudomonas aeruginosa: functional analysis in a heterologous host and role in the instability of mucoidy
Authors: Schurr M J , Martin D W , Mudd M H , Deretic V
Published: November 2016

Conversion to mucoidy, caused by the overproduction of the exopolysaccharide alginate in laboratory and cystic fibrosis strains of Pseudomonas aeruginosa, can occur via frameshift or nonsense mutations in the second gene of the algU mucA mucB cluster. The first gene of the cluster, algU, encodes a putative alternative sigma factor required for algD transcription. The algD gene encodes a critical alginate biosynthetic enzyme and is invariably activated in mucoid P. aeruginosa cells. To investigate the function of the genes controlling conversion to mucoidy, the wild-type algU mucA mucB cluster from the standard genetic strain PAO1 was used to reconstitute algD transcription in Escherichia coli. Transcription of an algD-lacZ chromosomal fusion in E. coli was detected upon introduction of plasmid-borne algU mucA mucB. Moreover, insertional inactivation of either mucA or mucB resulted in further stimulation of transcriptional activity from the algD promoter. This activation was dependent on algU, since a double algU mucA mutation abrogated transcription of algD. These experiments suggest that the phenotypic manifestations of muc mutations, i.e., increased algD expression and mucoid phenotype, depend on the presence of an active algU gene and that this regulator and the factors encoded by the downstream genes interact. Further support for these conclusions came from the investigations of the mechanism of reversion to nonmucoidy in P. aeruginosa, a phenomenon frequently referred to as the instability of mucoid phenotype. Spontaneous nonmucoid derivatives of the mucoid strain PAO578 carrying the mucA22 mutation were examined for the presence of alterations within the algU mucA mucB locus. Point mutations which inactivated algU were detected in some, but not all, nonmucoid revertants. No reversion of the original mucA22 mutation (a deletion of one C) was observed in any of the investigated strains. This observation suggests that the process of conversion to nonmucoidy ban be explained, at least partially, by second-site suppressor mutations and that a fraction of such mutations occurs in algU.
The Escherichia coli efg gene and the Rhodobacter capsulatus adgA gene code for NH3-dependent NAD synthetase
Authors: Willison J C , Tissot G
Published: November 2016

The essential gene efg, which complements ammonia-dependent growth (adgA) mutations in Rhodobacter capsulatus and is located at 38.1 min on the Escherichia coli chromosome, was found to code for NH3-dependent NAD synthetase. Crude extracts from a strain which overproduces the efg gene product contained up to 400 times more activity than crude extracts from the control strain, and the purified Efg protein possessed-NH3-dependent NAD synthetase activity. Glutamine-dependent NAD synthetase activity was found in crude extracts of E. coli but not in the purified enzyme, suggesting that it may be catalyzed by an additional subunit. An R. capsulatus strain carrying an adgA mutation was found to be deficient in NAD synthetase activity, and activity was restored by complementation with the E. coli gene. In accordance with the nomenclature proposed for Salmonella typhimurium (K. T. Hughes, B. M. Olivera, and J. R. Roth, J. Bacteriol. 170:2113-2120, 1988), the efg and adgA genes should now be designated nadE.
Cloning and characterization of the Inc A/C plasmid RA1 replicon
Authors: Llanes C , Gabant P , Couturier M , Michel-Briand Y
Published: November 2016

The Inc A/C plasmids, like Inc P and Inc Q plasmids, have a broad host range. However, their maintenance functions remain to be studied. An autoreplicative region of 2.79 kb named RepA/C, able to replicate both in the family Enterobacteriaceae and in Pseudomonas spp., was isolated and sequenced. The stability, copy number, and incompatibility expression of this replicon were determined. RepA/C and a nonautoreplicative fragment of 16 kb of this replicon were used as probes and showed specific hybridizations with the Inc P3-A/C plasmids from Pseudomonas spp. and members of the Enterobacteriaceae. These probes could be used as tools for identification of the plasmids of this epidemiologically important Inc group.
Proteus mirabilis MR/P fimbrial operon: genetic organization, nucleotide sequence, and conditions for expression
Authors: Bahrani F K , Mobley H L
Published: November 2016

Proteus mirabilis, an agent of urinary tract infection, expresses at least four fimbrial types. Among these are the MR/P (mannose-resistant/Proteus-like) fimbriae. MrpA, the structural subunit, is optimally expressed at 37 degrees C in Luria broth cultured statically for 48 h by each of seven strains examined. Genes encoding this fimbria were isolated, and the complete nucleotide sequence was determined. The mrp gene cluster encoded by 7,293 bp predicts eight polypeptides: MrpI (22,133 Da), MrpA (17,909 Da), MrpB (19,632 Da), MrpC (96,823 Da), MrpD (27,886 Da), MrpE (19,470 Da), MrpF (17,363 Da), and MrpG (13,169 Da). mrpI is upstream of the gene encoding the major structural subunit gene mrpA and is transcribed in the direction opposite to that of the rest of the operon. All predicted polypeptides share > or = 25% amino acid identity with at least one other enteric fimbrial gene product encoded by the pap, fim, smf, fan, or mrk gene clusters.
Viral DNA Sensors IFI16 and Cyclic GMP-AMP Synthase Possess Distinct Functions in Regulating Viral Gene Expression, Immune Defenses, and Apoptotic Responses during Herpesvirus Infection
Authors: Diner Benjamin A. , Lum Krystal K. , Toettcher Jared E. , Cristea Ileana M.
Published: November 2016

The human interferon-inducible protein IFI16 is an important antiviral factor that binds nuclear viral DNA and promotes antiviral responses. Here, we define IFI16 dynamics in space and time and its distinct functions from the DNA sensor cyclic dinucleotide GMP-AMP synthase (cGAS). Live-cell imaging reveals a multiphasic IFI16 redistribution, first to viral entry sites at the nuclear periphery and then to nucleoplasmic puncta upon herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV) infections. Optogenetics and live-cell microscopy establish the IFI16 pyrin domain as required for nuclear periphery localization and oligomerization. Furthermore, using proteomics, we define the signature protein interactions of the IFI16 pyrin and HIN200 domains and demonstrate the necessity of pyrin for IFI16 interactions with antiviral proteins PML and cGAS. We probe signaling pathways engaged by IFI16, cGAS, and PML using clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9-mediated knockouts in primary fibroblasts. While IFI16 induces cytokines, only cGAS activates STING/TBK-1/IRF3 and apoptotic responses upon HSV-1 and HCMV infections. cGAS-dependent apoptosis upon DNA stimulation requires both the enzymatic production of cyclic dinucleotides and STING. We show that IFI16, not cGAS or PML, represses HSV-1 gene expression, reducing virus titers. This indicates that regulation of viral gene expression may function as a greater barrier to viral replication than the induction of antiviral cytokines. Altogether, our findings establish coordinated and distinct antiviral functions for IFI16 and cGAS against herpesviruses.

IMPORTANCE
How mammalian cells detect and respond to DNA viruses that replicate in the nucleus is poorly understood. Here, we decipher the distinct functions of two viral DNA sensors, IFI16 and cGAS, during active immune signaling upon infection with two herpesviruses, herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV). We show that IFI16 rapidly oligomerizes at incoming herpesvirus genomes at the nuclear periphery to transcriptionally repress viral gene expression and limit viral replicative capacity. We further demonstrate that IFI16 does not initiate upstream activation of the canonical STING/TBK-1/IRF3 signaling pathway but is required for downstream antiviral cytokine expression. In contrast, we find that, upon DNA sensing during herpesvirus infection, cGAS triggers apoptosis in a STING-dependent manner. Our live-cell imaging, mass spectrometry-based proteomics, CRISPR-based cellular assays, and optogenetics underscore the value of integrative approaches to uncover complex cellular responses against pathogens.
The PAS Domain-Containing Protein HeuR Regulates Heme Uptake in Campylobacter jejuni
Authors: Johnson Jeremiah G. , Gaddy Jennifer A. , DiRita Victor J.
Published: November 2016

Campylobacter jejuni
is a leading cause of bacterially derived gastroenteritis. A previous mutant screen demonstrated that the heme uptake system (Chu) is required for full colonization of the chicken gastrointestinal tract. Subsequent work identified a PAS domain-containing regulator, termed HeuR, as being required for chicken colonization. Here we confirm that both the heme uptake system and HeuR are required for full chicken gastrointestinal tract colonization, with the
heuR
mutant being particularly affected during competition with wild-type
C. jejuni
. Transcriptomic analysis identified the
chu
genes—and those encoding other iron uptake systems—as regulatory targets of HeuR. Purified HeuR bound the
chuZA
promoter region in electrophoretic mobility shift assays. Consistent with a role for HeuR in
chu
expression,
heuR
mutants were unable to efficiently use heme as a source of iron under iron-limiting conditions, and mutants exhibited decreased levels of cell-associated iron by mass spectrometry. Finally, we demonstrate that an
heuR
mutant of
C. jejuni
is resistant to hydrogen peroxide and that this resistance correlates to elevated levels of catalase activity. These results indicate that HeuR directly and positively regulates iron acquisition from heme and negatively impacts catalase activity by an as yet unidentified mechanism in
C. jejuni
.

IMPORTANCE
Annually,
Campylobacter jejuni
causes millions of gastrointestinal infections in the United States, due primarily to its ability to reside within the gastrointestinal tracts of poultry, where it can be released during processing and contaminate meat. In the developing world, humans are often infected by consuming contaminated water or by direct contact with livestock. Following consumption of contaminated food or water, humans develop disease that is characterized by mild to severe diarrhea. There is a need to understand both colonization of chickens, to make food safer, and colonization of humans, to better understand disease. Here we demonstrate that to efficiently colonize a host,
C. jejuni
requires iron from heme, which is regulated by the protein HeuR. Understanding how HeuR functions, we can develop ways to inhibit its function and reduce iron acquisition during colonization, potentially reducing
C. jejuni
in the avian host, which would make food safer, or limiting human colonization.
The Cytoplasmic Tail Domain of Epstein-Barr Virus gH Regulates Membrane Fusion Activity through Altering gH Binding to gp42 and Epithelial Cell Attachment
Authors: Chen Jia , Jardetzky Theodore S. , Longnecker Richard
Published: November 2016

Epstein-Barr virus (EBV) is associated with infectious mononucleosis and a variety of cancers as well as lymphoproliferative disorders in immunocompromised patients. EBV mediates viral entry into epithelial and B cells using fusion machinery composed of four glycoproteins: gB, the gH/gL complex, and gp42. gB and gH/gL are required for both epithelial and B cell fusion. The specific role of gH/gL in fusion has been the most elusive among the required herpesvirus entry glycoproteins. Previous mutational studies have focused on the ectodomain of EBV gH and not on the gH cytoplasmic tail domain (CTD). In this study, we chose to examine the function of the gH CTD by making serial gH truncation mutants as well as amino acid substitution mutants to determine the importance of the gH CTD in epithelial and B cell fusion. Truncation of 8 amino acids (aa 698 to 706) of the gH CTD resulted in diminished fusion activity using a virus-free syncytium formation assay and fusion assay. The importance of the amino acid composition of the gH CTD was also investigated by amino acid substitutions that altered the hydrophobicity or hydrophilicity of the CTD. These mutations also resulted in diminished fusion activity. Interestingly, some of the gH CTD truncation mutants and hydrophilic tail substitution mutants lost the ability to bind to gp42 and epithelial cells. In summary, our studies indicate that the gH CTD is an important functional domain.

IMPORTANCE
Infection with Epstein-Barr virus (EBV) causes diseases ranging from the fairly benign infectious mononucleosis to life-threatening cancer. Entry into target cells is the first step for viral infection and is important for EBV to cause disease. Understanding the EBV entry mechanism is useful for the development of infection inhibitors and developing EBV vaccine approaches. Epithelial and B cells are the main target cells for EBV infection. The essential glycoproteins for EBV entry include gB, gH/gL, and gp42. We characterized the function of the EBV gH C-terminal cytoplasmic tail domain (CTD) in fusion using a panel of gH CTD truncation or substitution mutants. We found that the gH CTD regulates fusion by altering gp42 and epithelial cell attachment. Our studies may lead to a better understanding of EBV fusion and entry, which may result in novel therapies that target the EBV entry step.
A technical consideration when using flow diversion for recurrent aneurysms following stent-assisted coiling
Authors: Mascitelli Justin R , Wei Daniel , Oxley Thomas J , Kellner Christopher P , Shoirah Hazem , De Leacy Reade A , Mocco J , Fifi Johanna T
Published: November 2016

Flow diversion (FD) is a treatment option for recurrent aneurysms including following stent-assisted coiling (SAC), although this approach is both ‘off-label’ and unproven. A technical challenge of FD placement may involve the microwire catching on the tines of the previously placed stent or potentially going ‘in-out-in’ from the central axis of the stent. We report a case and technique that assures the wire has safely remained within the central axis of the stent. The procedure was performed in standard fashion except that the intermediate catheter was passed completely through the previously placed stent after the microwire/microcatheter had crossed. The large diameter of the intermediate catheter assured that the microwire did not go ‘in-out-in’. The intermediate catheter was completely withdrawn from the stent and the FD was placed in standard fashion. This technique may help to achieve complete FD opening and prevent thromboembolic complications associated with incomplete FD opening.
Nursing skill mix in European hospitals: cross-sectional study of the association with mortality, patient ratings, and quality of care
Authors: Aiken Linda H , Sloane Douglas , Griffiths Peter , Rafferty Anne Marie , Bruyneel Luk , McHugh Matthew , Maier Claudia B , Moreno-Casbas Teresa , Ball Jane E , Ausserhofer Dietmar , Sermeus Walter
Published: November 2016

Objectives

To determine the association of hospital nursing skill mix with patient mortality, patient ratings of their care and indicators of quality of care.

Design

Cross-sectional patient discharge data, hospital characteristics and nurse and patient survey data were merged and analysed using generalised estimating equations (GEE) and logistic regression models.

Setting

Adult acute care hospitals in Belgium, England, Finland, Ireland, Spain and Switzerland.

Participants

Survey data were collected from 13 077 nurses in 243 hospitals, and 18 828 patients in 182 of the same hospitals in the six countries. Discharge data were obtained for 275 519 surgical patients in 188 of these hospitals.

Main outcome measures

Patient mortality, patient ratings of care, care quality, patient safety, adverse events and nurse burnout and job dissatisfaction.

Results

Richer nurse skill mix (eg, every 10-point increase in the percentage of professional nurses among all nursing personnel) was associated with lower odds of mortality (OR=0.89), lower odds of low hospital ratings from patients (OR=0.90) and lower odds of reports of poor quality (OR=0.89), poor safety grades (OR=0.85) and other poor outcomes (0.80<OR<0.93), after adjusting for patient and hospital factors. Each 10 percentage point reduction in the proportion of professional nurses is associated with an 11% increase in the odds of death. In our hospital sample, there were an average of six caregivers for every 25 patients, four of whom were professional nurses. Substituting one nurse assistant for a professional nurse for every 25 patients is associated with a 21% increase in the odds of dying.

Conclusions

A bedside care workforce with a greater proportion of professional nurses is associated with better outcomes for patients and nurses. Reducing nursing skill mix by adding nursing associates and other categories of assistive nursing personnel without professional nurse qualifications may contribute to preventable deaths, erode quality and safety of hospital care and contribute to hospital nurse shortages.
The Wasserstein geometry of nonlinear σ models and the Hamilton–Perelman Ricci flow
Authors: Carfora Mauro
Published: November 2016

Nonlinear sigma models are quantum field theories describing, in the large deviation sense, random fluctuations of harmonic maps between a Riemann surface and a Riemannian manifold. Via their formal renormalization group analysis, they provide a framework for possible generalizations of the Hamilton–Perelman Ricci flow. By exploiting the heat kernel embedding introduced by Gigli and Mantegazza, we show that the Wasserstein geometry of the space of probability measures over Riemannian metric measure spaces provides a natural setting for discussing the relation between nonlinear sigma models and Ricci flow theory. In particular, we analyze the embedding of Ricci flow into a heat kernel renormalization group flow for dilatonic nonlinear sigma models, and characterize a non-trivial generalization of the Hamilton–Perelman version of the Ricci flow. We discuss in detail the monotonicity and gradient flow properties of this extended flow.
Fiber and crystals dual readout calorimeters
Authors: Cascella Michele , Franchino Silvia , Lee Sehwook
Published: November 2016

The RD52 (DREAM) collaboration is performing R&D on dual readout calorimetry techniques with the aim of improving hadronic energy resolution for future high energy physics experiments. The simultaneous detection of Cherenkov and scintillation light enables us to measure the electromagnetic fraction of hadron shower event-by-event. As a result, we could eliminate the main fluctuation which prevented from achieving precision energy measurement for hadrons. We have tested the performance of the lead and copper fiber prototypes calorimeters with various energies of electromagnetic particles and hadrons. During the beam test, we investigated the energy resolutions for electrons and pions as well as the identification of those particles in a longitudinally unsegmented calorimeter. Measurements were also performed on pure and doped PbWO4 crystals, as well as BGO and BSO, with the aim of realizing a crystal based dual readout detector. We will describe our results, focusing on the more promising properties of homogeneous media for the technique. Guidelines for additional developments on crystals will be also given. Finally we discuss the construction techniques that we have used to assemble our prototypes and give an overview of the ones that could be industrialized for the construction of a full hermetic calorimeter.
Film tension of liquid nano-film from molecular modeling
Authors: Peng Tiefeng , Yang Siyuan , Xiang Fan , Liang Yunpei , Li Qibin , Gao Xuechao , Liu Sanjun
Published: November 2016

Due to its geometry simplicity, the forces of thin liquid film are widely investigated and equivalently employed to explore the phys–chemical properties and mechanical stability of many other surfaces or colloid ensembles. The surface tension of bulk liquid ([Formula: see text]) and film tension ([Formula: see text]) are the most important parameters. Considering the insufficiency of detailed interpretation of film tension under micro-scale circumstances, a method for film tension was proposed based on numerical modeling. Assuming surface tension at different slab thicknesses being identical to the surface tension of film, the surface tension and disjoining pressure were subsequently used to evaluate the film tension based on the derivation of film thermodynamics, and a decreasing tendency was discovered for low temperature regions. The influence of saline concentration on nano-films was also investigated, and the comparison of film tensions suggested that higher concentration yielded larger film tension, with stronger decreasing intensity as a function of film thickness. Meanwhile, at thick film range (15–20 nm), film tension of higher concentration film continued to decrease as thickness increase, however it arrived to constant value for that of lower concentration. Finally, it was found that the film tension was almost independent on the film curvature, but varied with the thickness. The approach is applicable to symmetric emulsion films containing surfactants and bi-layer lipid films.
Effects of backreaction and exponential nonlinear electrodynamics on the holographic superconductors
Authors: Sheykhi A. , Shaker F.
Published: November 2016

We analytically study the properties of a [Formula: see text]-dimensional [Formula: see text]-wave holographic superconductor in the presence of exponential nonlinear (EN) electrodynamics. We consider the case in which the scalar and gauge fields back react on the background metric. Employing the analytical Sturm–Liouville method, we find that in the black hole background, the nonlinear electrodynamics correction will affect the properties of the holographic superconductors. We find that with increasing both backreaction and nonlinear parameters, the scalar hair condensation on the boundary will develop more difficult. We obtain the relation connecting the critical temperature with the charge density. Our analytical results support that, even in the presence of the nonlinear electrodynamics and backreaction, the phase transition for the holographic superconductor still belongs to the second-order and the critical exponent of the system always takes the mean-field value [Formula: see text].
Effects of isovector scalar meson on neutron star both with and without hyperon
Authors: Biswal S. K. , Kumar Bharat , Patra S. K.
Published: November 2016

We study the effects of isovector-scalar ([Formula: see text])-meson on neutron and hyperon stars. Influence of [Formula: see text]-meson on both static and rotating stars is discussed. The [Formula: see text]-meson in a neutron star consisting of protons, neutrons and electrons, makes the equations of states (EOS) stiffer at higher density, and consequently increases the maximum mass of the star. But induction of [Formula: see text]-meson in the hyperon star decreases the maximum mass. This is due to the early evolution of hyperons in presence of [Formula: see text]-meson.
Nuclear structure of low-lying states in 60,62,64,66Zn — A shell model description
Authors: Rai S. , Biswas A. , Mukherjee B.
Published: November 2016

Shell model calculation has been performed for even–even [Formula: see text]Zn using NuShellX code in [Formula: see text] model space with two different effective Hamiltonians, viz. JUN45 and jj44b. The low-lying structure is studied up to angular momentum, [Formula: see text] = 10[Formula: see text] by calculating level energies, reduced transition probabilities, occupation numbers, lifetimes, and quadrupole moments. The results of the calculations are compared with the available experimental data. It is observed that the inclusion of 1[Formula: see text] orbital in the model space is essential to understand nuclear structure in these isotopes. Shell model calculation with an improved set of effective Hamiltonian parameters and inclusion of [Formula: see text] orbital in the model space are necessary in order to produce finer agreement with the experimental observations.
EFFECTS OF HUNTING AND ESCAPING BEHAVIOR ON AN ECOSYSTEM CONSISTING OF ONE-PREDATOR AND TWO-PREY SPECIES
Authors: LEE SANG-HEE , KANG HYUK , KWON OHSUNG
Published: November 2016

In this study, we constructed a simple ecosystem consisting of one-predator–two-prey escape preferred strategy (EPS)- and hunting preferred strategy (HPS)-prey) — food for prey relationship to understand how the individual’s strategic behavior, hunting and escaping affects the ecosystem. In the model, when a prey encounters its predator and the food at the same time, either hunting or escaping should be taken as priority. Hunting priority is referred to as a HPS, while escape priority is referred to as an EPS. These strategies are associated with some degree of willingness to either hunt ([Formula: see text]) or escape ([Formula: see text]). In this model, two prey species were considered. One species (HPS-prey) takes HPS and the other rabbit species (EPS-prey) takes EPS. Predators take only HPS. Simulation results showed that the density of EPS-prey was obviously higher than that of HPS-prey in the appropriate values of [Formula: see text] and [Formula: see text] in the stable state. This means that when a prey individual has appropriate willingness for both hunting and escape, EPS is more beneficial for the survival than HPS. In addition, we briefly discussed the limitation of our model and the possible future improvements.
Discriminant as a product of local discriminants
Authors: Jakhar Anuj , Jhorar Bablesh , Khanduja Sudesh K. , Sangwan Neeraj
Published: November 2016

Let [Formula: see text] be a discrete valuation ring with maximal ideal [Formula: see text] and [Formula: see text] be the integral closure of [Formula: see text] in a finite separable extension [Formula: see text] of [Formula: see text]. For a maximal ideal [Formula: see text] of [Formula: see text], let [Formula: see text] denote respectively the valuation rings of the completions of [Formula: see text] with respect to [Formula: see text]. The discriminant satisfies a basic equality which says that [Formula: see text]. In this paper, we extend the above equality on replacing [Formula: see text] by the valuation ring of a Krull valuation of arbitrary rank and completion by henselization. In the course of proof, we prove a generalization of the well-known weak Approximation Theorem which is of independent interest as well.
Some types of ring elements in Ore extensions over noncommutative rings
Authors: Hashemi E. , Hamidizadeh M. , Alhevaz A.
Published: November 2016

Let [Formula: see text] be an associative unital ring with an endomorphism [Formula: see text] and [Formula: see text]-derivation [Formula: see text]. Some types of ring elements such as the units and the idempotents play distinguished roles in noncommutative ring theory, and will play a central role in this work. In fact, we are interested to study the unit elements, the idempotent elements, the von Neumann regular elements, the [Formula: see text]-regular elements and also the von Neumann local elements of the Ore extension ring [Formula: see text], when the base ring [Formula: see text] is a right duo ring which is [Formula: see text]-compatible. As an application, we completely characterize the clean elements of the Ore extension ring [Formula: see text], when the base ring [Formula: see text] is a right duo ring which is [Formula: see text]-compatible.
Preparation of Bulk Graphene Nanoplatelets by Spark Plasma Sintering — Electrical and Thermal Properties
Authors: Prasad Mattipally , Rao Tata N. , Prasad P. S. R. , Babu D. Suresh
Published: November 2016

Consolidation of graphene nanoplatelets (GNPs) by spark plasma sintering (SPS) to study the feasibility of its structure retention at extreme temperature and pressure conditions. Structural characterization of the GNP powder and pellet were carried out by Micro-Raman, SEM, and TEM. HT-XRD. A.C. and D.C. conductivity of GNP pellet is carried out at room temperature. GNPs survived its structure in the SPS processing at an extreme temperature of 1850[Formula: see text]C and uni-axial pressure 60[Formula: see text]MPa, vacuum at [Formula: see text] Torr. Our study shows the potential for GNPs to be successfully used as a reinforcing in ceramic matrix composites using SPS. The diffraction has been accurately calibrated to waterfall the shift in 2[Formula: see text] values at elevated temperatures. The corrected lattice parameter data have been used to estimate the instantaneous and mean thermal expansion coefficients as a function of temperature. The lattice parameters “[Formula: see text]” and “[Formula: see text]” for powder and pellet GNP is found to be 0.2456(1)[Formula: see text]nm and 0.6700(2)[Formula: see text]nm, respectively. The thermal expansivity of GNP powder and pellet along “[Formula: see text]”- and “[Formula: see text]”-axis are found to be [Formula: see text][Formula: see text]K[Formula: see text], [Formula: see text][Formula: see text]K[Formula: see text] and [Formula: see text][Formula: see text]K[Formula: see text], [Formula: see text][Formula: see text]K[Formula: see text], respectively. Electrical conductivity of GNP pellet is found to be 5700[Formula: see text]S/m.
Synthesis of Mesoporous Silica Monoliths — A Novel Approach Towards Fabrication of Solid-State Optical Sensors for Environmental Applications
Authors: Prabhakaran D. , Subashini C. , Akhila Maheswari M.
Published: November 2016

Mesoporous silica monoliths are an attractive area of research owing to their high specific surface area, uniform channels and mesoporous size (2–30[Formula: see text]nm). This paper deals with the direct templating synthesis of a mesoporous worm-like silica monolithic material using F127 — a triblock copolymer, by micro-emulsion technique using trimethyl benzene (TMB), as the solvent. The synthesized silica monolith is characterized using SEM-EDAX, XRD, BET, NMR and FT-IR. The monolith shows an ordered worm-like mesoporous structure with tuneable through pores, an excellent host for the anchoring of chromo-ionophores for the naked-eye metal ion-sensing. The mesoporous monoliths were loaded with 4-dodecyl-6-(2-pyridylazo)-phenol (DPAP) ligand through direct immobilization, thereby acting as solid-state naked-eye colorimetric ion-sensors for the sensing toxic Pb[Formula: see text] ions at parts-per-billion (ppb) level in various industrial and environmental systems. The influence of various experimental parameters such as solution pH, limiting ligand loading concentration, amount of monolith material, matrix tolerance level, limit of detection and quantification has been studied and optimized.
Influence of Initial Inclined Surface Crack on Estimated Residual Fatigue Lifetime of Railway Axle
Authors: Náhlík Luboš , Pokorný Pavel , Ševčík Martin , Hutař Pavel
Published: November 2016

Railway axles are subjected to cyclic loading which can lead to fatigue failure. For safe operation of railway axles a damage tolerance approach taking into account a possible defect on railway axle surface is often required. The contribution deals with an estimation of residual fatigue lifetime of railway axle with initial inclined surface crack. 3D numerical model of inclined semi-elliptical surface crack in railway axle was developed and its curved propagation through the axle was simulated by finite element method. Presence of press-fitted wheel in the vicinity of initial crack was taken into account. A typical loading spectrum of railway axle was considered and residual fatigue lifetime was estimated by NASGRO approach. Material properties of typical axle steel EA4T were considered in numerical calculations and lifetime estimation.
Water Evaporation-Induced Self-Assembly of Hierarchical CuO/MnO2 Composite Nanospheres and their Applications in Lithium-Ion Batteries
Authors: Zeng Chunyan , Gao Chen , Yuan Li , Liang Tao , Yang Ruisong , Zhang Wei , Nie Song
Published: November 2016

In this paper, hierarchical CuO/MnO2 composite hollow nanospheres have been successfully fabricated by water evaporation-induced self-assembly through a redox transformation reaction between Cu2O nanospheres and KMnO4 solution at 120[Formula: see text]C for 6[Formula: see text]h, followed by removing the residual Cu2O cores with ammonia hydroxide solution. The outstanding feature of this method is that the reaction system is in a dynamic environment due to the evaporation of the solvent water, which benefits the self-assembly of nanostructures to form hierarchical structures. Both Kirkendall effect and Ostwald ripening mechanism are suggested to be responsible for the formation of the hierarchical CuO/MnO2 nanocomposites according to the characterization results. The electrochemical properties of the products were studied, and the results show that the hierarchical CuO/MnO2 hollow nanospheres exhibit high capacity and good rate performance (a stable capacity of about 480[Formula: see text]mAh[Formula: see text]g[Formula: see text] after 80 cycles of variable charging rate), which is probably attributed to the hierarchical hollow nanostructures.
A note on transforming a weak solution to PDE to a smooth solution
Authors: Alghalith Moawia
Published: November 2016

This is paper, we develop a simple method that transforms weak solutions to PDEs to smooth solutions. We apply our method to the portfolio model.
Increases in human motoneuron excitability after cervical spinal cord injury depend on the level of injury
Authors: Thomas Christine K. , Häger Charlotte K. , Klein Cliff S.
Published: November 2016

After human spinal cord injury (SCI), motoneuron recruitment and firing rate during voluntary and involuntary contractions may be altered by changes in motoneuron excitability. Our aim was to compare F waves in single thenar motor units paralyzed by cervical SCI to those in uninjured controls because at the single-unit level F waves primarily reflect the intrinsic properties of the motoneuron and its initial segment. With intraneural motor axon stimulation, F waves were evident in all 4 participants with C4-level SCI, absent in 8 with C5 or C6 injury, and present in 6 of 12 Uninjured participants ( P < 0.001). The percentage of units that generated F waves differed across groups (C4: 30%, C5 or C6: 0%, Uninjured: 16%; P < 0.001). Mean (±SD) proximal axon conduction velocity was slower after C4 SCI [64 ± 4 m/s ( n = 6 units), Uninjured: 73 ± 8 m/s ( n = 7 units); P = 0.037]. Mean distal axon conduction velocity differed by group [C4: 40 ± 8 m/s ( n = 20 units), C5 or C6: 49 ± 9 m/s ( n = 28), Uninjured: 60 ± 7 m/s ( n = 45); P < 0.001]. Motor unit properties (EMG amplitude, twitch force) only differed after SCI ( P ≤ 0.004), not by injury level. Motor units with F waves had distal conduction velocities, M-wave amplitudes, and twitch forces that spanned the respective group range, indicating that units with heterogeneous properties produced F waves. Recording unitary F waves has shown that thenar motoneurons closer to the SCI (C5 or C6) have reduced excitability whereas those further away (C4) have increased excitability, which may exacerbate muscle spasms. This difference in motoneuron excitability may be related to the extent of membrane depolarization following SCI.

NEW & NOTEWORTHY Unitary F waves were common in paralyzed thenar muscles of people who had a chronic spinal cord injury (SCI) at the C4 level compared with uninjured people, but F waves did not occur in people that had SCI at the C5 or C6 level. These results highlight that intrinsic motoneuron excitability depends, in part, on how close the motoneurons are to the site of the spinal injury, which could alter the generation and strength of voluntary and involuntary muscle contractions.
Solid-State 13C NMR Spectroscopy Applied to the Study of Carbon Blacks and Carbon Deposits Obtained by Plasma Pyrolysis of Natural Gas
Authors: Freitas Jair C. C. , Cipriano Daniel F. , Zucolotto Carlos G. , Cunha Alfredo G. , Emmerich Francisco G.
Published: November 2016

Solid-state 13C nuclear magnetic resonance (NMR) spectroscopy was used in this work to analyze the physical and chemical properties of plasma blacks and carbon deposits produced by thermal cracking of natural gas using different types of plasma reactors. In a typical configuration with a double-chamber reactor, N2 or Ar was injected as plasma working gas in the first chamber and natural gas was injected in the second chamber, inside the arc column. The solid residue was collected at different points throughout the plasma apparatus and analyzed by 13C solid-state NMR spectroscopy, using either cross polarization (CP) or direct polarization (DP), combined with magic angle spinning (MAS). The 13C CP/MAS NMR spectra of a number of plasma blacks produced in the N2 plasma reactor showed two resonance bands, broadly identified as associated with aromatic and aliphatic groups, with indication of the presence of oxygen- and nitrogen-containing groups in the aliphatic region of the spectrum. In contrast to DP experiments, only a small fraction of 13C nuclei in the plasma blacks are effectively cross-polarized from nearby 1H nuclei and are thus observed in spectra recorded with CP. 13C NMR spectra are thus useful to distinguish between different types of carbon species in plasma blacks and allow a selective study of groups spatially close to hydrogen in the material.
Process Mapping in a Pediatric Emergency Department to Minimize Missed Urinary Tract Infections
Authors: Black Morgan , Singh Valene , Belostotsky Vladimir , Roy Madan , Yamamura Deborah , Gambarotto Kathryn , Lau Keith , Kam April J.
Published: November 2016

Urinary tract infections (UTIs) are common in young children and are seen in emergency departments (EDs) frequently. Left untreated, UTIs can lead to more severe conditions. Our goal was to undertake a quality improvement (QI) initiative to help minimize the number of children with missed UTIs in a newly established tertiary care pediatric emergency department (PED). A retrospective chart review was undertaken to identify missed UTIs in children < 3 years old who presented to a children’s hospital’s ED with positive urine cultures. It was found that there was no treatment or follow-up in 12% of positive urine cultures, indicating a missed or possible missed UTI in a significant number of children. Key stakeholders were then gathered and process mapping (PM) was completed, where gaps and barriers were identified and interventions were subsequently implemented. A follow-up chart review was completed to assess the impact of PM in reducing the number of missed UTIs. Following PM and its implementation within the ED, there was no treatment or follow-up in only 1% of cases. Based on our results, the number of potentially missed UTIs in the ED decreased dramatically, indicating that PM can be a successful QI tool in an acute care pediatric setting.
Risk Factors and Treatment for Hemorrhage after Pancreaticoduodenectomy: A Case Series of 423 Patients
Authors: Gao Feng , Li Jianguo , Quan Shengwei , Li Fujun , Ma Donglai , Yao Lei , Zhang Ping
Published: November 2016

The study aimed to investigate the risk factors of postpancreatectomy hemorrhage (PPH) after pancreaticoduodenectomy (PD). A retrospective analysis of 423 patients who underwent PD between January 2008 and January 2014 was conducted. The overall incidence and all-cause mortality of PPH were 9.9% (42/423) and 2.1% (9/423), respectively. Independent risk factors of early PPH were revascularization (odds ratio (OR) = 6.786; 95% confidence interval (95% CI): 1.785–25.792; P=0.005), history of abdominal surgery (OR = 5.009; 95% CI: 1.968–12.749; P=0.001), and preoperative albumin levels (OR = 4.863; 95% CI: 1.962–12.005; P=0.001). Independent risk factors of late PPH included postoperative pancreatic leakage (OR = 4.696; 95% CI: 1.605–13.740; P=0.005), postoperative biliary fistula (OR = 6.096; 95% CI: 1.575–23.598; P=0.009), postoperative abdominal infection (OR = 4.605; 95% CI: 1.108–19.144; P=0.036), revascularization (OR = 9.943; 95% CI: 1.900–52.042; P=0.007), history of abdominal surgery (OR = 8.790; 95% CI: 2.779–27.806; P<0.001), and preoperative albumin levels (OR = 5.563; 95% CI: 1.845–16.776; P=0.002).
Clinical Performance of an Ultrahigh Resolution Chromosomal Microarray Optimized for Neurodevelopmental Disorders
Authors: Ho Karen S. , Twede Hope , Vanzo Rena , Harward Erin , Hensel Charles H. , Martin Megan M. , Page Stephanie , Peiffer Andreas , Mowery-Rushton Patricia , Serrano Moises , Wassman E. Robert
Published: November 2016

Copy number variants (CNVs) as detected by chromosomal microarray analysis (CMA) significantly contribute to the etiology of neurodevelopmental disorders, such as developmental delay (DD), intellectual disability (ID), and autism spectrum disorder (ASD). This study summarizes the results of 3.5 years of CMA testing by a CLIA-certified clinical testing laboratory 5487 patients with neurodevelopmental conditions were clinically evaluated for rare copy number variants using a 2.8-million probe custom CMA optimized for the detection of CNVs associated with neurodevelopmental disorders. We report an overall detection rate of 29.4% in our neurodevelopmental cohort, which rises to nearly 33% when cases with DD/ID and/or MCA only are considered. The detection rate for the ASD cohort is also significant, at 25%. Additionally, we find that detection rate and pathogenic yield of CMA vary significantly depending on the primary indications for testing, the age of the individuals tested, and the specialty of the ordering doctor. We also report a significant difference between the detection rate on the ultrahigh resolution optimized array in comparison to the array from which it originated. This increase in detection can significantly contribute to the efficient and effective medical management of neurodevelopmental conditions in the clinic.
Long Term Compression Strength of Mortars Produced Using Coarse Steel Slag as Aggregate
Authors: Furlani Erika , Maschio Stefano
Published: November 2016

The paper reports on some experimental results obtained from the production of mortars prepared using a commercial cement, coarse steelmaking slag, superplasticizer, and water. The behaviour of this reference composition was compared to that of some others containing further additives in order to investigate materials compressive strength after long time ageing. It has been demonstrated that an optimized water/cement ratio coupled with slag particles of size lower than 2.5 mm and proper protocol of preparation leads to the production of materials with good mechanical properties after 28, 90, and 180 days of ageing. The resulting materials therefore appeared as good candidates for civil engineering applications. However, the present research also demonstrates that the mortar samples of all of the compositions prepared suffer from decay and compressive strength decrease after long time ageing in water. In the present paper the results are explained taking account of materials residual porosity and alkali silica reaction which occurs in the samples.