bluuebunny/crossref_metadata_2025 huggingface dataset:
Cloning of the debranching-enzyme gene from Thermoanaerobium brockii into Escherichia coli and Bacillus subtilis
Authors: Coleman R D , Yang S S , McAlister M P
Published: November 2016

The gene for an enzyme with single or dual specificity on complex carbohydrates has been transferred from its native host (Thermoanaerobium brockii), a thermophilic anaerobe, into Escherichia coli and Bacillus subtilis. Most of the gene coding region is in a 2.2-kilobase PstI fragment that is common to the E. coli and B. subtilis chimeric vectors pCPC902 and pCPC903, respectively. Although the T. brockii debranching enzyme secreted from B. subtilis was unglycosylated and had less thermostability, more enzyme was secreted from B. subtilis (0.80 to 1.0 U/ml) than from T. brockii (0.23 U/ml). E. coli did not export any measurable enzyme. From the fermentation broth of B. subtilis containing pCPC903, three active species of the debranching enzyme were separated; two species are possibly protease digestion products of the larger protein (105,000 molecular weight). Whereas the enzyme can cleave all of the alpha-1----6 glucosidic linkages (and none of the alpha-1----4 bonds) in pullulan, it hydrolyzed mostly alpha-1----4 and very few of the alpha-1----6 linkages in starch. Upon hydrolysis of pullulan by the enzyme, only maltotriose was produced, while starch was digested to various-sized oligomers.
High-affinity potassium uptake system in Bacillus acidocaldarius showing immunological cross-reactivity with the Kdp system from Escherichia coli
Authors: Bakker E P , Borchard A , Michels M , Altendorf K , Siebers A
Published: November 2016

During growth with low levels of K+, Bacillus acidocaldarius expressed a high-affinity K+ uptake system. The following observations indicate that this system strongly resembles the Kdp-ATPase of Escherichia coli: (i) its high affinity for K+ (Km of 20 microM or below); (ii) its poor transport of Rb+; (iii) the enhanced ATPase activity of membranes derived from cells grown with low levels of K+ (this activity was stimulated by K+ and inhibited by vanadate); (iv) the expression of an extra protein with a molecular weight of 70,000 in cells grown with low levels of K+; and (v) the immunological cross-reactivity of this 70,000-molecular-weight protein with antibodies against the catalytic subunit B of the E. coli Kdp system. Antibodies against the complete E. coli Kdp system, which immunoprecipitated the whole E. coli KdpABC complex, almost exclusively precipitated the 70,000-molecular-weight protein from detergent-solubilized B. acidocaldarius membranes. The possibility that the B. acidocaldarius Kdp system consists of a single, KdpB-type subunit is discussed.
Interrupted thymidylate synthase gene of bacteriophages T2 and T6 and other potential self-splicing introns in the T-even bacteriophages
Authors: Chu F K , Maley F , Martinez J , Maley G F
Published: November 2016

Southern hybridization analyses of procaryotic DNA from Escherichia coli, lambda bacteriophage, and T1 to T7 phages were carried out. The hybridization probes used consisted of DNA restriction fragments derived from the T4 phage intron-containing thymidylate synthase gene (td) and short synthetic oligodeoxynucleotides defining specific exon and intron regions of the gene. It was shown that intact as well as restricted DNA from the T-even phages hybridized not only to both T4 phage td intron- and exon-specific probes but also to probes defining the td 5' (exon I-intron) and 3' (intron-exon II) presplice junctions. These data strongly suggest that, analogous to the T4 phage, only the T2 and T6 phages among the procaryotes tested contain interrupted td genes. The td intervening sequence in each phage is roughly 1 kilobase pair (kb) in size and interrupts the td gene at a site analogous to that in the T4 phage. This was confirmed by data from Northern (RNA) hybridization analysis of td-specific in vitro transcripts of these phage DNAs. [alpha-32P]GTP in vitro labeling of total RNA from T4 phage-infected cells produced five species of labeled RNAs that were 1, 0.9, 0.83, 0.75, and 0.6 kb in size. Only the 1-, 0.9-, and 0.75-kb species were labeled in RNA from T2- or T6-infected cells. The commonly present 1-kb RNA is the excised td intron, which exists in both linear and circular forms in the respective T-even-phage-infected cells, while the 0.6-kb RNA unique to T4 may be the excised intron derived from the ribonucleotide reductase small subunit gene (nrdB) of the phage. The remaining labeled RNA species are likely candidates for other self-splicing introns.
Characterization of the Erwinia carotovora pelB gene and its product pectate lyase
Authors: Lei S P , Lin H C , Wang S S , Callaway J , Wilcox G
Published: November 2016

The pelB gene encodes pectate lyase B, one of three pectate lyases identified in Erwinia carotovora EC. Pectate lyase B was purified from Escherichia coli containing the pelB gene on a recombinant plasmid. The activity of the protein was optimal at a pH of 8.3. The amino acid composition, N-terminal amino acid sequence, and C-terminal peptide sequence were determined and compared with the polypeptide sequence deduced from the DNA sequence of pelB. Purified pectate lyase B started at amino acid 23 of the predicted sequence, suggesting that a 22-amino-acid leader peptide had been removed. Pectate lyase B of E. carotovora EC and pectate lyase B of E. chrysanthemi EC16 contain 352 and 353 amino acids, respectively (N. T. Keen, S. Tanaki, W. Belser, D. Dahlbeck, and B. Staskawicz, J. Bacteriol. 168:595-606, 1986). The two proteins are 72% homologous on the basis of DNA sequence data, and 75% of the amino acids are identical.
Integration host factor and conjugative transfer of the antibiotic resistance plasmid R100
Authors: Dempsey W B
Published: November 2016

Transfer of plasmid R100-1 was reduced 100-fold in the absence of integration host factor.
Different levels of DNA methylation in yeast and mycelial forms of Candida albicans
Authors: Russell P J , Welsch J A , Rachlin E M , McCloskey J A
Published: November 2016

Isotope dilution gas chromatography-mass spectrometry analysis of genomic DNAs isolated from three Candida albicans isolates showed significant differences in the amounts of 5-methyldeoxycytidine (m5Cyt) in DNA from yeast-form and from mycelial-form cells; the moles percent m5Cyt were 0.11, 0.11, and 0.097 for yeast-form DNA and 0.045, 0.053, and 0.047 for mycelial-form DNA for the three isolates Sh8, 9938, and B311, respectively. The lower m5Cyt values for mycelial-form cells suggest that those cells may exhibit significantly greater gene activity than yeast-form cells.
A Two-Component Regulatory System Impacts Extracellular Membrane-Derived Vesicle Production in Group A Streptococcus
Authors: Resch Ulrike , Tsatsaronis James Anthony , Le Rhun Anaïs , Stübiger Gerald , Rohde Manfred , Kasvandik Sergo , Holzmeister Susanne , Tinnefeld Philip , Wai Sun Nyunt , Charpentier Emmanuelle
Published: November 2016

Export of macromolecules via extracellular membrane-derived vesicles (MVs) plays an important role in the biology of Gram-negative bacteria. Gram-positive bacteria have also recently been reported to produce MVs; however, the composition and mechanisms governing vesiculogenesis in Gram-positive bacteria remain undefined. Here, we describe MV production in the Gram-positive human pathogen group A streptococcus (GAS), the etiological agent of necrotizing fasciitis and streptococcal toxic shock syndrome. M1 serotype GAS isolates in culture exhibit MV structures both on the cell wall surface and in the near vicinity of bacterial cells. A comprehensive analysis of MV proteins identified both virulence-associated protein substrates of the general secretory pathway in addition to “anchorless surface proteins.” Characteristic differences in the contents, distributions, and fatty acid compositions of specific lipids between MVs and GAS cell membrane were also observed. Furthermore, deep RNA sequencing of vesicular RNAs revealed that GAS MVs contained differentially abundant RNA species relative to bacterial cellular RNA. MV production by GAS strains varied in a manner dependent on an intact two-component system, CovRS, with MV production negatively regulated by the system. Modulation of MV production through CovRS was found to be independent of both GAS cysteine protease SpeB and capsule biosynthesis. Our data provide an explanation for GAS secretion of macromolecules, including RNAs, lipids, and proteins, and illustrate a regulatory mechanism coordinating this secretory response.

IMPORTANCE
Group A streptococcus (GAS) is a Gram-positive bacterial pathogen responsible for more than 500,000 deaths annually. Establishment of GAS infection is dependent on a suite of proteins exported via the general secretory pathway. Here, we show that GAS naturally produces extracellular vesicles with a unique lipid composition that are laden with proteins and RNAs. Interestingly, both virulence-associated proteins and RNA species were found to be differentially abundant in vesicles relative to the bacteria. Furthermore, we show that genetic disruption of the virulence-associated two-component regulator CovRS leads to an increase in vesicle production. This study comprehensively describes the protein, RNA, and lipid composition of GAS-secreted MVs and alludes to a regulatory system impacting this process.
Metabolism of Toxic Sugars by Strains of the Bee Gut Symbiont Gilliamella apicola
Authors: Zheng Hao , Nishida Alex , Kwong Waldan K. , Koch Hauke , Engel Philipp , Steele Margaret I. , Moran Nancy A.
Published: November 2016

Social bees collect carbohydrate-rich food to support their colonies, and yet, certain carbohydrates present in their diet or produced through the breakdown of pollen are toxic to bees. The gut microbiota of social bees is dominated by a few core bacterial species, including the Gram-negative species
Gilliamella apicola
. We isolated 42 strains of
G. apicola
from guts of honey bees and bumble bees and sequenced their genomes. All of the
G. apicola
strains share high 16S rRNA gene similarity, but they vary extensively in gene repertoires related to carbohydrate metabolism. Predicted abilities to utilize different sugars were verified experimentally. Some strains can utilize mannose, arabinose, xylose, or rhamnose (monosaccharides that can cause toxicity in bees) as their sole carbon and energy source. All of the
G. apicola
strains possess a
manO
-associated mannose family phosphotransferase system; phylogenetic analyses suggest that this was acquired from
Firmicutes
through horizontal gene transfer. The metabolism of mannose is specifically dependent on the presence of mannose-6-phosphate isomerase (MPI). Neither growth rates nor the utilization of glucose and fructose are affected in the presence of mannose when the gene encoding MPI is absent from the genome, suggesting that mannose is not taken up by
G. apicola
strains which harbor the phosphotransferase system but do not encode the MPI. Given their ability to simultaneously utilize glucose, fructose, and mannose, as well as the ability of many strains to break down other potentially toxic carbohydrates,
G. apicola
bacteria may have key roles in improving dietary tolerances and maintaining the health of their bee hosts.

IMPORTANCE
Bees are important pollinators of agricultural plants. Our study documents the ability of
Gilliamella apicola
, a dominant gut bacterium in honey bees and bumble bees, to utilize several sugars that are harmful to bee hosts. Using genome sequencing and growth assays, we found that the ability to metabolize certain toxic carbohydrates is directly correlated with the presence of their respective degradation pathways, indicating that metabolic potential can be accurately predicted from genomic data in these gut symbionts. Strains vary considerably in their range of utilizable carbohydrates, which likely reflects historical horizontal gene transfer and gene deletion events. Unlike their bee hosts,
G. apicola
bacteria are not detrimentally affected by growth on mannose-containing medium, even in strains that cannot metabolize this sugar. These results suggest that
G. apicola
may be an important player in modulating nutrition in the bee gut, with ultimate effects on host health.
Hepatitis C Virus Proteins Interact with the Endosomal Sorting Complex Required for Transport (ESCRT) Machinery via Ubiquitination To Facilitate Viral Envelopment
Authors: Barouch-Bentov Rina , Neveu Gregory , Xiao Fei , Beer Melanie , Bekerman Elena , Schor Stanford , Campbell Joseph , Boonyaratanakornkit Jim , Lindenbach Brett , Lu Albert , Jacob Yves , Einav Shirit
Published: November 2016

Enveloped viruses commonly utilize late-domain motifs, sometimes cooperatively with ubiquitin, to hijack the
e
ndosomal
s
orting
c
omplex
r
equired for
t
ransport (ESCRT) machinery for budding at the plasma membrane. However, the mechanisms underlying budding of viruses lacking defined late-domain motifs and budding into intracellular compartments are poorly characterized. Here, we map a network of hepatitis C virus (HCV) protein interactions with the ESCRT machinery using a mammalian-cell-based protein interaction screen and reveal nine novel interactions. We identify HRS (hepatocyte growth factor-regulated tyrosine kinase substrate), an ESCRT-0 complex component, as an important entry point for HCV into the ESCRT pathway and validate its interactions with the HCV nonstructural (NS) proteins NS2 and NS5A in HCV-infected cells. Infectivity assays indicate that HRS is an important factor for efficient HCV assembly. Specifically, by integrating capsid oligomerization assays, biophysical analysis of intracellular viral particles by continuous gradient centrifugations, proteolytic digestion protection, and RNase digestion protection assays, we show that HCV co-opts HRS to mediate a late assembly step, namely, envelopment. In the absence of defined late-domain motifs, K63-linked polyubiquitinated lysine residues in the HCV NS2 protein bind the HRS ubiquitin-interacting motif to facilitate assembly. Finally, ESCRT-III and VPS/VTA1 components are also recruited by HCV proteins to mediate assembly. These data uncover involvement of ESCRT proteins in intracellular budding of a virus lacking defined late-domain motifs and a novel mechanism by which HCV gains entry into the ESCRT network, with potential implications for other viruses.

IMPORTANCE
Viruses commonly bud at the plasma membrane by recruiting the host ESCRT machinery via conserved motifs termed late domains. The mechanism by which some viruses, such as HCV, bud intracellularly is, however, poorly characterized. Moreover, whether envelopment of HCV and other viruses lacking defined late domains is ESCRT mediated and, if so, what the entry points into the ESCRT pathway are remain unknown. Here, we report the interaction network of HCV with the ESCRT machinery and a critical role for HRS, an ESCRT-0 complex component, in HCV envelopment. Viral protein ubiquitination was discovered to be a signal for HRS binding and HCV assembly, thereby functionally compensating for the absence of late domains. These findings characterize how a virus lacking defined late domains co-opts ESCRT to bud intracellularly. Since the ESCRT machinery is essential for the life cycle of multiple viruses, better understanding of this virus-host interplay may yield targets for broad-spectrum antiviral therapies.
Abdominal tuberculosis: an old disease surprising young doctors
Authors: Sousa Marta David , Batista Joana , Pacheco Patricia , Nunes Vitor
Published: November 2016

Tuberculosis remains a worldwide public health concern. Atypical extrapulmonary presentations may delay the diagnosis and treatment. We present the case of an adult woman admitted to the emergency department with bowel obstruction. The putative intraoperative diagnostic hypothesis was ovarian cancer with peritoneal dissemination. Histopathological analysis showed a chronic granulomatous inflammatory disease with acid-fast bacilli. The patient was started on an alternative parenteral antituberculosis drug combination until oral feeding was available. Currently, 5 months after surgery, she is asymptomatic. Abdominal tuberculosis is the most frequent extrapulmonary site with a wide range of clinical presentations. Emergency laparotomy may be necessary in patients who present with acute abdomen. Bowel obstruction due to adhesions and strictures is not infrequent. However, tuberculous abdominal cocoon presentation as in our patient is rare. Treatment with parenteral alternative drug regimens for tuberculosis is mandatory until the oral route is available.
Women's health: a new global agenda
Authors: Peters Sanne A E , Woodward Mark , Jha Vivekanand , Kennedy Stephen , Norton Robyn
Published: November 2016

Global efforts to improve the health of women largely focus on improving sexual and reproductive health. However, the global burden of disease has changed significantly over the past decades. Currently, the greatest burden of death and disability among women is attributable to non-communicable diseases (NCDs), most notably cardiovascular diseases, cancers, respiratory diseases, diabetes, dementia, depression and musculoskeletal disorders. Hence, to improve the health of women most efficiently, adequate resources need to be allocated to the prevention, management and treatment of NCDs in women. Such an approach could reduce the burden of NCDs among women and also has the potential to improve women's sexual and reproductive health, which commonly shares similar behavioural, biological, social and cultural risk factors. Historically, most medical research was conducted in men and the findings from such studies were assumed to be equally applicable to women. Sex differences and gender disparities in health and disease have therefore long been unknown and/or ignored. Since the number of women in studies is increasing, evidence for clinically meaningful differences between men and women across all areas of health and disease has emerged. Systematic evaluation of such differences between men and women could improve the understanding of diseases, as well as inform health practitioners and policymakers in optimising preventive strategies to reduce the global burden of disease more efficiently in women and men.
Evaluation of the electronic self-report Symptom Screening in Pediatrics Tool (SSPedi)
Authors: O'Sullivan Cathy , Lee Dupuis L , Gibson Paul , Johnston Donna L , Baggott Christina , Portwine Carol , Spiegler Brenda , Kuczynski Susan , Tomlinson Deborah , Tomlinson George A , Sung Lillian
Published: November 2016

Objective

We previously developed the paper-based Symptom Screening in Pediatrics Tool (SSPedi) designed for paediatric cancer symptom screening. Objectives were to evaluate and refine the electronic mobile application (app) of SSPedi using the opinions of children with cancer.

Methods

Participants were children 8–18 years of age with cancer. Participants completed electronic SSPedi on their own and then responded to semistructured questions to determine whether they found electronic SSPedi easy or difficult to complete and understand, understood and liked the app features (audio and animation), and understood previously difficult to understand concepts with the introduction of a help menu. After each group of 10 children, responses were reviewed to determine whether modifications were required.

Results

20 children evaluated electronic SSPedi. None found electronic SSPedi difficult to complete or understand. All children understood the app features and each of the 4 more difficult to understand concepts after using the help menu. 19 of 20 children thought the app was a good way to communicate with doctors and nurses.

Conclusions

We finalised an electronic version of SSPedi that is easy to use and understand with features specifically designed to facilitate child self-report. Future work will evaluate the psychometric properties of electronic SSPedi.
Alterations in the epithelial stem cell compartment could contribute to permanent changes in the mucosa of patients with ulcerative colitis
Authors: Dotti Isabella , Mora-Buch Rut , Ferrer-Picón Elena , Planell Núria , Jung Peter , Masamunt M Carme , Leal Raquel Franco , Martín de Carpi Javier , Llach Josep , Ordás Ingrid , Batlle Eduard , Panés Julián , Salas Azucena
Published: November 2016

Objective

UC is a chronic inflammatory disease of the colonic mucosa. Growing evidence supports a role for epithelial cell defects in driving pathology. Moreover, long-lasting changes in the epithelial barrier have been reported in quiescent UC. Our aim was to investigate whether epithelial cell defects could originate from changes in the epithelial compartment imprinted by the disease.

Design

Epithelial organoid cultures (EpOCs) were expanded ex vivo from the intestinal crypts of non-IBD controls and patients with UC. EpOCs were induced to differentiate (d-EpOCs), and the total RNA was extracted for microarray and quantitative real-time PCR (qPCR) analyses. Whole intestinal samples were used to determine mRNA expression by qPCR, or protein localisation by immunostaining.

Results

EpOCs from patients with UC maintained self-renewal potential and the capability to give rise to differentiated epithelial cell lineages comparable with control EpOCs. Nonetheless, a group of genes was differentially regulated in the EpOCs and d-EpOCs of patients with UC, including genes associated with antimicrobial defence (ie,LYZ,PLA2G2A), with secretory (ie,ZG16,CLCA1) and absorptive (ie,AQP8,MUC12) functions, and with a gastric phenotype (ie,ANXA10,CLDN18andLYZ). A high rate of concordance was found in the expression profiles of the organoid cultures and whole colonic tissues from patients with UC.

Conclusions

Permanent changes in the colonic epithelium of patients with UC could be promoted by alterations imprinted in the stem cell compartment. These changes may contribute to perpetuation of the disease.
Prevalence and incidence of gout in southern Sweden from the socioeconomic perspective
Authors: Kapetanovic Meliha C , Hameed Mohaned , Turkiewicz Aleksandra , Neogi Tuhina , Saxne Tore , Jacobsson Lennart , Englund Martin
Published: November 2016

Objectives

To estimate the prevalence and cumulative incidence of gout in southern Sweden with respect to socioeconomic status.

Methods

Among residents of Skåne region in the year 2013 (total population 1.3 million), adult persons (age 18 years +) who between 1998 and 2013 received a diagnosis of gout (International Classification of Disease 10th Edition (ICD-10) code M10) by any physician were identified using the Skåne Healthcare Register. We calculated the point prevalence by end of 2013 and annual cumulative incidence in 2013 standardised to the whole Skåne population according to sex, individual information on occupation (white collar/blue collar), income (low/middle/high) and level of education (primary school/high school/university).

Results

The crude 2013 point prevalence of gout and 2013 cumulative incidence (95% CI) were 1.69% (1.66% to 1.71%) and 24 cases per 10 000 persons (23–25), respectively. Compared to women, men had higher point prevalence (2.44% (2.40% to 2.49%) vs 0.96% (0.93% to 0.98%)) and higher annual cumulative incidence (33 cases per 10 000 (32–35)) versus 15 (14–16)). These figures increased with higher age but decreased with higher level of education, being the lowest in individuals with a university degree. Persons with middle income had highest point prevalence and cumulative incidence of gout, while those with white collar occupations had the lowest.

Conclusions

Gout is the most common inflammatory arthritis in southern Sweden with a prevalence of ∼1.7% in the adult population. There is a socioeconomic gradient with more gout present in the lower level of education and with more manual labour.
Sleep apnoea and stroke
Authors: Sharma Sameer , Culebras Antonio
Published: November 2016

Sleep disorders have been known to physicians for a long time. In his famous aphorisms, Hippocrates said “Sleep or watchfulness exceeding that which is customary, augurs unfavorably”. Modern medicine has been able to disentangle some of the phenomena that disturb sleep. Among the most notable offenders is sleep apnoea that has gained prominence in the past few decades. It is being proposed as one of the potentially modifiable risk factors for vascular diseases including stroke. The pathological mechanisms linking sleep apnoea to vascular risk factors include hypoxia, cardiac arrhythmias, dysautonomia, impaired glucose tolerance, hypertension, dyslipidaemia and inflammation. In this article, we review literature linking sleep apnoea and stroke, including sleep apnoea as a risk factor for primary prevention with the potential to improve outcome after acute stroke and as a secondary risk factor, amenable to modification and hence vascular risk reduction.
Impact of feeding and housing systems on disease incidence in dairy calves
Authors: Curtis G. C. , Argo C. McG. , Jones D. , Grove‐White D. H.
Published: November 2016

Contentious issues in calf rearing include milk feeding level and single versus group housing. The current study was performed on a high‐producing 170 Holstein cow dairy farm to investigate the impact of nutrition and housing on disease incidence. Calves (n=100) were allocated in birth order to one of two commonly used feeding strategies. Group A calves were group housed from birth and fed ad libitum milk replacer (MR) via a computerised machine using a single teat, with weaning commencing at 63 days. Group R calves were initially housed in individual pens receiving 2.5 litres of MR twice daily via a bucket until three weeks of age when they were group housed and fed 3 litres of MR twice daily via a group trough with weaning commencing at 56 days. In total, 80 (80 per cent) calves suffered from at least one incident of disease during the period from birth to 12 weeks. Group A calves had a greater risk of disease than group R calves (diarrhoea: OR 3.86 (95 per cent CI 1.67 to 8.9); pneumonia: OR 5.80 (95 per cent CI 2.33 to 14.44)). There was a 5.1 per cent incidence of failure of passive transfer of Ig assessed via measurement of plasma total protein concentrations at 48 hours of age. It is hypothesised that the increased diarrhoea risk in group A calves was most likely associated with group housing, while the increased pneumonia risk was associated with the use of a single teat allowing increased transmission of pathogens from calf to calf.
Lactoferrin interacts with bile acids and increases fecal cholesterol excretion in rats
Authors: Nakamura Kanae , Morishita Satoru , Ono Tomoji , Murakoshi Michiaki , Sugiyama Keikichi , Kato Hisanori , Ikeda Ikuo , Nishino Hoyoku
Published: November 2016

Lactoferrin (LF) is a multifunctional cationic protein (pI 8.2–8.9) in mammalian milk. We previously reported that enteric-LF prevented hypercholesterolemia and atherosclerosis in a diet-induced atherosclerosis model using Microminipig, although the underlying mechanisms remain unclear. Because LF is assumed to electrostatically interact with bile acids to inhibit intestinal cholesterol absorption, LF could promote cholesterol excretion. In this study, we assessed the interaction between LF and taurocholate in vitro, and the effect of LF on cholesterol excretion in rats. The binding rate of taurocholate to LF was significantly higher than that to transferrin (pI 5.2–6.3). When rats were administered a high-cholesterol diet (HCD) containing 5% LF, LF was detected using ELISA in the upper small intestine from 7.5 to 60 min after the administration. Rats were fed one of the following diets: control, HCD, or HCD + 5% LF for 21 days. Fecal neutral steroids and hepatic cholesterol levels in the HCD group were significantly higher than those in the control group. The addition of LF to a HCD significantly increased fecal neutral steroids levels (22% increase, p < 0.05) and reduced hepatic cholesterol levels (17% decrease, p < 0.05). These parameters were inversely correlated (R = −0.63, p < 0.05). These results suggest that LF promotes cholesterol excretion via interactions with bile acids.
Modeling the implications of stock mixing and life history uncertainty of Atlantic bluefin tuna
Authors: Kerr Lisa A. , Cadrin Steven X. , Secor David H. , Taylor Nathan G.
Published: November 2016

Atlantic bluefin tuna (Thunnus thynnus) is currently managed as two separate eastern and western stocks, despite information indicating considerable stock mixing. Using a simulation model, we explored how scenarios of population-specific migration and uncertainty in aspects of bluefin tuna biology affect the magnitude, distribution, and mixed stock nature of the resource and catch of its associated fisheries. The analytical framework was a stochastic, age-structured, stock-overlap model that was seasonally and spatially explicit with movement of eastern- and western-origin tuna informed by tagging and otolith chemistry data. Alternate estimates of movement and assumptions regarding maturity and recruitment regime for western-origin fish were considered. Simulation of the operating model indicated considerable stock mixing in the western and central Atlantic, which resulted in differences between the stock and population view of western bluefin tuna. The relative biomass of the western population and its spatial and temporal distribution in the Atlantic was sensitive to model assumptions and configurations. Simulation modeling can provide a means to ascertain the potential consequences of stock mixing on the assessment and management of fishery resources.
Higgs particles interacting via a scalar dark matter field
Authors: Bhattacharya Yajnavalkya , Darewych Jurij W.
Published: November 2016

We study a system of two Higgs bound state, interacting via a real scalar dark matter (DM) mediating field, without imposing Z2 symmetry on the DM sector of the postulated Lagrangian. The variational method in the Hamiltonian formalism of QFT is used to derive relativistic wave equations for the two-Higgs system, using a truncated Fock space trial state. Approximate solutions of the two-body relativistic coupled integral equations are presented, and conditions for the existence of Higgs bound states are examined in a broad parameter space of DM mass and coupling constants.
Applying a Bauhaus design approach to conceptualize an integrated system of mental health care: Lessons from a large urban hospital
Authors: Ungar Thomas , Taube-Schiff Marlene , Stergiopoulos Vicky
Published: November 2016

We have applied a Bauhaus design lens to inform a visual conceptual framework for a rational mental health care system. We believe that Canada’s healthcare system can often be fragmented and does not always allow for service delivery to easily meet patient care needs. Within our proposed framework, the form of services provided follows patient- and healthcare-centred needs. The framework is also informed by the ethics and values of social responsibility, population health, and principles of quality of care. We review evidence for this framework (based on need, acuity, risk, service intensity, and provider level) and describe patient care pathways from intake/triage to three patient-centred tiers of care: (1) primary care (low needs), (2) acute ambulatory transitional care (moderate needs), and (3) acute hospital and complex care (high needs). Within each tier, various models of care are organized from low to high service intensity as informed by reports from the British Columbia Ministry of Health and the World Health Organization. We hope that our model may help to better conceptualize and organize our mental health care system and help providers clarify roles, responsibilities, and accountabilities to improve quality of care.
Effects of active flux on plasma behavior and weld shape in laser welding of X5CrNi189 stainless steel
Authors: Dai Hongbin , Peng Jun
Published: November 2016

In this paper, stainless steel was welded by active flux-aided laser welding method. The effects of single active flux (Cr2O3, SiO2 and TiO2) and composite active flux on laser welding were studied. In the welding process, laser plasma behavior was recorded by a high-speed imaging system. The results show that, with the addition of active flux, the absorption of laser energy and melting efficiency increase. In the laser power of 750 W, effects of active flux on weld depth to width ratio are given by the order: composite active flux [Formula: see text] SiO[Formula: see text] Cr2O[Formula: see text] TiO2. The effect of composite active flux is the most significant and it can increase the weld depth to width ratio to 85%. Active flux can restrict the laser plasma. With the addition of composite active flux, the projected area of laser plasma obtained obviously reduced, and it can be reduced by 41.39%. Active flux cannot obviously change the main components in weld zone, but can change the grains of austenite and ferrite.
A Fourier Collocation Approach for Transit-Time Ultrasonic Flowmeter Under Multi-Phase Flow Conditions
Authors: Simurda Matej , Lassen Benny , Duggen Lars , Basse Nils T.
Published: November 2016

A numerical model for a clamp-on transit-time ultrasonic flowmeter (TTUF) under multi-phase flow conditions is presented. The method solves equations of linear elasticity for isotropic heterogeneous materials with background flow where acoustic media are modeled by setting shear modulus to zero. Spatial derivatives are calculated by a Fourier collocation method allowing the use of the fast Fourier transform (FFT) and time derivatives are approximated by a finite difference (FD) scheme. This approach is sometimes referred to as a pseudospectral time-domain method. Perfectly matched layers (PML) are used to avoid wave-wrapping and staggered grids are implemented to improve stability and efficiency. The method is verified against exact analytical solutions and the effect of the time-staggering and associated lowest number of points per minimum wavelengths value is discussed. The method is then employed to model a complete TTUF measurement setup to simulate the effect of a flow profile on the flowmeter accuracy and a study of an impact of inclusions in flowing media on received signals is carried out.
SHIELDING GAS AND HEAT INPUT EFFECTS ON THE MECHANICAL AND METALLURGICAL CHARACTERIZATION OF GAS METAL ARC WELDING OF SUPER MARTENSITIC STAINLESS STEEL (12Cr5Ni2Mo) JOINTS
Authors: PRABAKARAN T. , PRABHAKAR M. , SATHIYA P.
Published: November 2016

This paper deals with the effects of shielding gas mixtures (100% CO2, 100% Ar and 80 % Ar [Formula: see text] 20% CO[Formula: see text] and heat input (3.00, 3.65 and 4.33[Formula: see text]kJ/mm) on the mechanical and metallurgical characteristics of AISI 410[Formula: see text]S (American Iron and Steel Institute) super martensitic stainless steel (SMSS) by gas metal arc welding (GMAW) process. AISI 410[Formula: see text]S SMSS with 1.2[Formula: see text]mm diameter of a 410 filler wire was used in this study. A detailed microstructural analysis of the weld region as well as the mechanical properties (impact, microhardness and tensile tests at room temperature and 800[Formula: see text]C) was carried out. The tensile and impact fracture surfaces were further analyzed through scanning electron microscope (SEM). 100% Ar shielded welds have a higher amount of [Formula: see text] ferrite content and due to this fact the tensile strength of the joints is superior to the other two shielded welds.
Conditions on p-subgroups implying p-supersolvability
Authors: Guo Xiuyun , Zhang Boru
Published: November 2016

In this note, we use fewer [Formula: see text]-subgroups [Formula: see text] with the condition [Formula: see text] to investigate the structure of finite groups. We prove that for a fixed prime [Formula: see text], a given Sylow [Formula: see text]-subgroup [Formula: see text] of a finite group [Formula: see text], and a power [Formula: see text] of [Formula: see text] dividing [Formula: see text] such that [Formula: see text], if [Formula: see text] is normal in [Formula: see text] for all non-cyclic normal subgroups [Formula: see text] of [Formula: see text] with [Formula: see text], then either [Formula: see text] is [Formula: see text]-supersoluble or else [Formula: see text]. This extends the main result of Guo and Isaacs (Conditions on [Formula: see text]-subgroups implying [Formula: see text]-nilpotence or [Formula: see text]-supersolvability, Arch. Math. 105 (2015) 215–222). We also derive some applications of the above result which extend some known results.
Robust multiscale analytic sampling approximation to periodic function and fast algorithm
Authors: Li Youfa , Shang Jing , Zhang Gengrong , Dang Pei
Published: November 2016

By applying the multiscale method to the Möbius transformation function, we construct the multiscale analytic sampling approximation (MASA) to any function in the Hardy space [Formula: see text]. The approximation error is estimated, and it is proved that the MASA is robust to sample error. We prove that the MASA can be expressed by a Hankel matrix, making use of which, a fast algorithm is established to compute the MASA. Since what we acquire in practice may well be the samples on time domain instead of the analytic ones on the unit disc of the complex plane, we establish a fast algorithm for acquiring analytic samples. Numerical experiments are carried out to demonstrate the efficiency of the MASA.
Perforation of Steel Targets by Blunt Projectiles Using Smoothed Particle Hydrodynamics Method
Authors: Li Ruiyu , Sun Yuxin , Sun Qiran , Zhao Yayun , Feng Jiangtuo
Published: November 2016

In this paper, perforations of 12[Formula: see text]mm thick Weldox 460E steel plates by 20[Formula: see text]mm diameter blunt projectiles are simulated based on Two-dimensional Smoothed Particle Hydrodynamics method (SPH), and the modified Johnson–Cook (MJC) material model is adopted. To describe the shear plugging process, the particle approximation between different materials is canceled, and only the particle contact model based on the principle of conservation of momentum is applied. Then the separation of projectile and plug is simulated successfully, which is consistent with the experimental observations. Furthermore, it can be found that the particle size has a great influence on the calculation by comparing the effects of the different SPH particle sizes on plugging calculations. In general, the smaller the particle size is, the greater the residual velocity of projectile is. The residual velocities are tending towards stability as the decrease of particle size. Taking computational efficiency and accuracy into consideration, 0.033 (size[Formula: see text][Formula: see text][Formula: see text]0.4[Formula: see text]mm) is the most appropriate dimensionless particle size. Then, the effect of target thickness on perforation is conducted, which shows that the target thickness has certain influence on the global deformation of target. Moreover, the sensitivity of MJC material constants on the residual velocity of projectile is also analyzed and discussed using orthogonal experimental design method and the range analysis method. The results indicate that the most sensitivity parameter is yield strength [Formula: see text], followed by strain hardening modulus [Formula: see text] and strain hardening exponent [Formula: see text].
Sintering and kinetic mechanism of Si3N4-SiC micro-nano composite by spark plasma sintering
Authors: Khajelakzay Mohammad , Bakhshi Saeed Reza , Borhani Gholam Hossein , Ramazani Mazaher
Published: November 2016

Si3N4–SiC composites were fabricated by spark plasma sintering at 1700[Formula: see text]C for 480 S with MgSiN2 and Y2O3 as additives. The morphology and phase characterization of the composites were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The values of [Formula: see text] parameter indicate that the grain boundary reaction is the rate controller at 1500[Formula: see text]C and diffusion becomes the controlling step at 1550[Formula: see text]C. The nanohardness and Young’s modulus attained the maximum value of 18.5 and 316[Formula: see text]GPa, respectively.
High-order numerical method for the derivative nonlinear Schrödinger equation
Authors: Li Shu-Cun , Li Xiang-Gui , Cao Jun-Jie , Li Wen-Bo
Published: November 2016

In this work, a fourth-order numerical scheme in space and two second-order numerical schemes in both time and space are proposed for the derivative nonlinear Schrödinger equation. We verify the mass conservation for the two-level implicit scheme. The influence on the soliton solution by adding a small random perturbation to the initial condition is discussed. The numerical experiments are given to test the accuracy order for different schemes, respectively. We also test the conservative property of mass and Hamiltonian for these schemes from the numerical point of view.
Quantifying remaining oil saturation using time-lapse seismic amplitude changes at fluid contacts
Authors: Alvarez Erick , MacBeth Colin , Brain Jonathan
Published: November 2016

Our study shows that time-lapse changes in the amplitude of the seismic reflection at an oil–water contact (OWC) and/or produced OWC can be used to estimate directly the displacement efficiency of water displacing oil,
E
D
, without the need of a rock and fluid physics model. From this value, it is possible to determine the remaining oil saturation if required. A preliminary application is performed using several published literature examples, which are reinterpreted to assess the average
E
D
and ensure that the theory is consistent with expectations. Next, a North Sea field model with a known
E
D
is used to create fluid-flow predictions and the corresponding synthetic time-lapse seismic data. Application to these data again confirms the basic principles of the method and defines the accuracy when applied to 4D seismic data. Finally, an observed 4D seismic dataset from a producing field in the North Sea is analysed. The results suggest a displacement efficiency of between 21 and 65% with an accuracy of 3% due to data non-repeatability (with a NRMS of between 11 and 13%). Given an average irreducible water saturation of 0.32, this calculates the remaining oil saturations at between 24 and 53% for this field. A prerequisite for use of the proposed OWC approach is that a discrete contact be interpreted on either the 3D or 4D seismic datasets. Therefore, successful application of this technique requires moderate- to high-quality seismic data and a fairly thick reservoir sequence without significant structural complexity.
Chronic hyperprolactinemia evoked by disruption of lactotrope dopamine D2 receptors impacts on liver and adipocyte genes related to glucose and insulin balance
Authors: Luque Guillermina María , Lopez-Vicchi Felicitas , Ornstein Ana María , Brie Belén , De Winne Catalina , Fiore Esteban , Perez-Millan Maria Inés , Mazzolini Guillermo , Rubinstein Marcelo , Becu-Villalobos Damasia
Published: November 2016

We studied the impact of high prolactin titers on liver and adipocyte gene expression related to glucose and insulin homeostasis in correlation with obesity onset. To that end we used mutant female mice that selectively lack dopamine type 2 receptors (D2Rs) from pituitary lactotropes (lacDrd2KO), which have chronic high prolactin levels associated with increased body weight, marked increments in fat depots, adipocyte size, and serum lipids, and a metabolic phenotype that intensifies with age. LacDrd2KO mice of two developmental ages, 5 and 10 mo, were used. In the first time point, obesity and increased body weight are marginal, although mice are hyperprolactinemic, whereas at 10 mo there is marked adiposity with a 136% increase in gonadal fat and a 36% increase in liver weight due to lipid accumulation. LacDrd2KO mice had glucose intolerance, hyperinsulinemia, and impaired insulin response to glucose already in the early stages of obesity, but changes in liver and adipose tissue transcription factors were time and tissue dependent. In chronic hyperprolactinemic mice liver Prlr were upregulated, there was liver steatosis, altered expression of the lipogenic transcription factor Chrebp, and blunted response of Srebp-1c to refeeding at 5 mo of age, whereas no effect was observed in the glycogenesis pathway. On the other hand, in adipose tissue a marked decrease in lipogenic transcription factor expression was observed when morbid obesity was already settled. These adaptive changes underscore the role of prolactin signaling in different tissues to promote energy storage.
The role of dietary fat in obesity-induced insulin resistance
Authors: Lackey Denise E. , Lazaro Raul G. , Li Pingping , Johnson Andrew , Hernandez-Carretero Angelina , Weber Natalie , Vorobyova Ivetta , Tsukomoto Hidekazu , Osborn Olivia
Published: November 2016

Consumption of excess calories results in obesity and insulin resistance and has been intensively studied in mice and humans. The objective of this study was to determine the specific contribution of dietary fat rather than total caloric intake to the development of obesity-associated insulin resistance. We used an intragastric feeding method to overfeed excess calories from a low-fat diet (and an isocalorically matched high-fat diet) through a surgically implanted gastric feeding tube to generate obesity in wild-type mice followed by hyperinsulinemic-euglycemic clamp studies to assess the development of insulin resistance. We show that overfeeding a low-fat diet results in levels of obesity similar to high-fat diet feeding in mice. However, despite a similar body weight, obese high-fat diet-fed mice are more insulin resistant than mice fed an isocaloric low-fat diet. Therefore, increased proportion of calories from dietary fat further potentiates insulin resistance in the obese state. Furthermore, crossover diet studies revealed that reduction in dietary fat composition improves glucose tolerance in obesity. In the context of the current obesity and diabetes epidemic, it is particularly important to fully understand the role of dietary macronutrients in the potentiation and amelioration of disease.
Right prefrontal cortex transcranial direct current stimulation enhances multi-day savings in sensorimotor adaptation
Authors: Seidler Rachael D. , Gluskin Brittany S. , Greeley Brian
Published: November 2016

We have previously reported that visuospatial working memory performance and magnitude of activation in the right dorsolateral prefrontal cortex predict the rate of visuomotor adaptation. Recent behavioral studies suggest that sensorimotor savings, or faster relearning on second exposure to a task, are due to recall of these early, strategic components of adaptation. In the present study we applied anodal transcranial direct current stimulation to right or left prefrontal cortex or left motor cortex. We found that all groups adapted dart throwing movements while wearing prism lenses at the same rate as subjects receiving sham stimulation on day 1. On test day 2, which was conducted a few days later, the right prefrontal and left motor cortex groups adapted faster than the sham group. Moreover, only the right prefrontal group exhibited greater savings, expressed as a greater difference between day 1 and day 2 errors, compared with sham stimulation. These findings support the hypothesis that the right prefrontal cortex contributes to sensorimotor adaptation and savings.

NEW & NOTEWORTHY We have previously reported that visuospatial working memory performance and magnitude of activation in the right dorsolateral prefrontal cortex predict the rate of manual visuomotor adaptation. Sensorimotor savings, or faster adaptation to a previously experienced perturbation, has been recently linked to cognitive processes. We show that facilitating the right prefrontal cortex with anodal transcranial direct current stimulation enhances sensorimotor savings compared with sham stimulation.