bluuebunny/crossref_metadata_2025 huggingface dataset:
Overexpression of the Efflux Pumps SmeVWX and SmeDEF Is a Major Cause of Resistance to Co-trimoxazole in Stenotrophomonas maltophilia
Authors: Sánchez María Blanca , Martínez José Luis
Published: March 2018

Co-trimoxazole is one of the antimicrobials of choice for treating
Stenotrophomonas maltophilia
infections. Most works on the molecular epidemiology of the resistance to this drug combination are based on the analysis of
sul
genes. Nevertheless, the existence of clinical co-trimoxazole-resistant
S. maltophilia
isolates that do not harbor
sul
genes has been reported. To investigate potential mutations that can reduce the susceptibility of
S. maltophilia
to co-trimoxazole, spontaneous
S. maltophilia
co-trimoxazole-resistant mutants isolated under different co-trimoxazole concentrations were studied. All mutants presented phenotypes compatible with the overexpression of either SmeVWX (94.6%) or SmeDEF (5.4%). Indeed, the analysis of a selected set of strains showed that the overexpression of either of these efflux pumps, which was due to mutations in their regulators
smeRv
and
smeT
, respectively, was the cause of co-trimoxazole resistance. No other efflux pump was overexpressed in any of the studied mutants, indicating that they do not participate in the observed resistance phenotype. The analysis of mutants overexpressing or lacking SmeDEF or SmeVWX shows that SmeDEF contributes to the intrinsic and acquired resistance to co-trimoxazole in
S. maltophilia
, whereas SmeVWX only contributes to acquired resistance. It is important to highlight that all mutants were less susceptible to other antibiotics, including chloramphenicol and quinolones. Since both SmeVWX and SmeDEF are major determinants of quinolone resistance, the potential cross-selection of resistance to co-trimoxazole and quinolones, when either of the antimicrobials is used, is of particular concern for the treatment of
S. maltophilia
infections.
Identification and Characterization of Key Charged Residues in the Cofilin Protein Involved in Azole Susceptibility, Apoptosis, and Virulence of Aspergillus fumigatus
Authors: Lu Zhongyi , Jia Xiaodong , Chen Yong , Han Xuelin , Chen Fangyan , Tian Shuguang , Su Xueting , Li Zongwei , Zhao Jingya , Zhang Xi , Hu Mandong , Huang Liuyu , Han Li
Published: March 2018

Through some specific amino acid residues, cofilin, a ubiquitous actin depolymerization factor, can significantly affect mitochondrial function related to drug resistance and apoptosis in
Saccharomyces cerevisiae
; however, this modulation in a major fungal pathogen,
Aspergillus fumigatus
, was still unclear. Hereby, it was found, first, that mutations on several charged residues in cofilin to alanine, D19A-R21A, E48A, and K36A, increased the formation of reactive oxygen species and induced apoptosis along with typical hallmarks, including mitochondrial membrane potential depolarization, cytochrome
c
release, upregulation of metacaspases, and DNA cleavage, in
A. fumigatus
. Two of these mutations (D19A-R21A and K36A) increased acetyl coenzyme A and ATP concentrations by triggering fatty acid β-oxidation. The upregulated acetyl coenzyme A affected the ergosterol biosynthetic pathway, leading to overexpression of
cyp51A
and -
B
, while excess ATP fueled ATP-binding cassette transporters. Besides, both of these mutations reduced the susceptibility of
A. fumigatus
to azole drugs and enhanced the virulence of
A. fumigatus
in a
Galleria mellonella
infection model. Taken together, novel and key charged residues in cofilin were identified to be essential modules regulating the mitochondrial function involved in azole susceptibility, apoptosis, and virulence of
A. fumigatus
.
Complete Genome Sequencing of Eight Brucella abortus Biovar 1 Strains Isolated from Water Buffalo
Authors: Paradiso Rubina , Orsini Massimiliano , Riccardi Marita Georgia , Cecere Bianca , Cerrone Anna , Cammà Cesare , Chiusano Maria Luisa , Galiero Giorgio , Borriello Giorgia
Published: March 2018

Brucellosis is a zoonotic disease caused by bacteria of the genus
Brucella
. The disease is endemic in many areas, causing chronic infections responsible for reproductive disorders in infected animals. Here, we present eight complete genome assemblies of eight
Brucella abortus
strains isolated from water buffaloes farmed in the Campania region.
Phylogenetic Characterization of Salmonella enterica Serovar Typhimurium and Its Monophasic Variant Isolated from Food Animals in Japan Revealed Replacement of Major Epidemic Clones in the Last 4 Decades
Authors: Arai Nobuo , Sekizuka Tsuyoshi , Tamamura Yukino , Tanaka Kiyoshi , Barco Lisa , Izumiya Hidemasa , Kusumoto Masahiro , Hinenoya Atsushi , Yamasaki Shinji , Iwata Taketoshi , Watanabe Ayako , Kuroda Makoto , Uchida Ikuo , Akiba Masato
Published: March 2018

Salmonella enterica
serovar Typhimurium (
Salmonella
Typhimurium) and its monophasic variant (
Salmonella
4,[5],12:i:−) are the major causes of gastroenteritis in both humans and animals. Pulsed-field gel electrophoresis and multilocus variable-number tandem-repeat analysis have been used widely as subtyping methods for these pathogens in molecular epidemiological analyses, but the results do not precisely reflect phylogenetic information. In this study, we performed a phylogenetic analysis of these serovars using whole-genome sequencing data and identified nine distinct genotypic clades. Then, we established an allele-specific PCR-based genotyping method detecting a clade-specific single nucleotide polymorphism to rapidly identify the clade of each isolate. Among a total of 815 isolates obtained from cattle in Japan between 1977 and 2017, clades 1, 7, and 9 contained 77% of isolates. Obvious replacement of the dominant clone was observed five times in this period, and clade 9, which mostly contains
Salmonella
4,[5],12:i:−, is currently dominant. Among 140 isolates obtained from swine in Japan between 1976 and 2017, clades 3 and 9 contained 64% of isolates. Clade 9 is the latest clone as is the case in cattle isolates. Clade 9 is similar to an epidemic clone from Europe, which is characterized by sequence type 34 (ST34), chromosomal
Salmonella
genomic island 3, and a composite transposon containing antimicrobial resistance genes. The increased prevalence of clade 9 among food animals in Japan might be a part of the pandemic of the European
Salmonella
4,[5],12:i:− clone.
Mechanisms of Host IFI16, PML, and Daxx Protein Restriction of Herpes Simplex Virus 1 Replication
Authors: Merkl Philipp E. , Orzalli Megan H. , Knipe David M.
Published: March 2018

The initial events after DNA virus infection involve a race between epigenetic silencing of the incoming viral DNA by host cell factors and expression of viral genes. Several host gene products, including the nuclear domain 10 (ND10) components PML (promyelocytic leukemia) and Daxx (death domain-associated protein 6), as well as IFI16 (interferon-inducible protein 16), have been shown to restrict herpes simplex virus 1 (HSV-1) replication. Whether IFI16 and ND10 components work together or separately to restrict HSV-1 replication is not known. To determine the combinatorial effects of IFI16 and ND10 proteins on viral infection, we depleted Daxx or PML in primary human foreskin fibroblasts (HFFs) in the presence or absence of IFI16. Daxx or IFI16 depletion resulted in higher
ICP0
mutant viral yields, and the effects were additive. Surprisingly, small interfering RNA (siRNA) depletion of PML in the HFF cells led to decreased ICP0-null virus replication, while short hairpin RNA (shRNA) depletion led to increased ICP0-null virus replication, arguing that different PML isoforms or PML-related proteins may have restrictive or proviral functions. In normal human cells, viral DNA replication increases expression of all classes of HSV-1 genes. We observed that IFI16 repressed transcription from both parental and progeny DNA genomes. Taken together, our results show that the mechanisms of action of IFI16 and ND10 proteins are independent, at least in part, and that IFI16 exerts restrictive effects on both input and replicated viral genomes. These results raise the potential for distinct mechanisms of action of IFI16 on parental and progeny viral DNA molecules.

IMPORTANCE
Many human DNA viruses transcribe their genomes and replicate in the nucleus of a host cell, where they exploit the host cell nuclear machinery for their own replication. Host factors attempt to restrict viral replication by blocking such events, and viruses have evolved mechanisms to neutralize the host restriction factors. In this study, we provide information about the mechanisms of action of three host cell factors that restrict replication of herpes simplex virus (HSV). We found that these factors function independently and that one acts to restrict viral transcription from parental and progeny viral DNA genomes. These results provide new information about how cells counter DNA virus replication in the nucleus and provide possible approaches to enhance the ability of human cells to resist HSV infection.
Host Factor SPCS1 Regulates the Replication of Japanese Encephalitis Virus through Interactions with Transmembrane Domains of NS2B
Authors: Ma Le , Li Fang , Zhang Jing-Wei , Li Wei , Zhao Dong-Ming , Wang Han , Hua Rong-Hong , Bu Zhi-Gao
Published: March 2018

Signal peptidase complex subunit 1 (SPCS1) is a newly identified host factor that regulates flavivirus replication, but the molecular mechanism is not fully understood. Here, using Japanese encephalitis virus (JEV) as a model, we investigated the mechanism through which the host factor SPCS1 regulates the replication of flaviviruses. We first validated the regulatory function of SPCS1 in JEV propagation by knocking down and knocking out endogenous SPCS1. The loss of SPCS1 function markedly reduced intracellular virion assembly and the production of infectious JEV particles but did not affect cell entry, RNA replication, or translation of the virus. SPCS1 was found to interact with nonstructural protein 2B (NS2B), which is involved in posttranslational protein processing and virus assembly. Serial deletion mutation of the JEV NS2B protein revealed that two transmembrane domains, NS2B(1–49) and NS2B(84–131), interact with SPCS1. Further mutagenesis analysis of conserved flavivirus residues in two SPCS1 interaction domains of NS2B demonstrated that G12A, G37A, and G47A in NS2B(1–49) and P112A in NS2B(84–131) weakened the interaction with SPCS1. Deletion mutation of SPCS1 revealed that SPCS1(91–169), which contains two transmembrane domains, was involved in interactions with both NS2B(1–49) and NS2B(84–131). Taken together, these results demonstrate that SPCS1 affects viral replication by interacting with NS2B, thereby influencing the posttranslational processing of JEV proteins and the assembly of virions.

IMPORTANCE
Understanding virus-host interactions is important for elucidating the molecular mechanisms of virus propagation and identifying potential antiviral targets. Previous reports demonstrated that SPCS1 is involved in the flavivirus life cycle, but the mechanism remains unknown. In this study, we confirmed that SPCS1 participates in the posttranslational protein processing and viral assembly stages of the JEV life cycle but not in the cell entry, genome RNA replication, or translation stages. Furthermore, we found that SPCS1 interacts with two independent transmembrane domains of the flavivirus NS2B protein. NS2B also interacts with NS2A, which is proposed to mediate virus assembly. Therefore, we propose a protein-protein interaction model showing how SPCS1 participates in the assembly of JEV particles. These findings expand our understanding of how host factors participate in the flavivirus replication life cycle and identify potential antiviral targets for combating flavivirus infection.
Caspase-Dependent Apoptosis Induction via Viral Protein ORF4 of Porcine Circovirus 2 Binding to Mitochondrial Adenine Nucleotide Translocase 3
Authors: Lin Cui , Gu Jinyan , Wang Huijuan , Zhou Jianwei , Li Jiarong , Wang Shengnan , Jin Yulan , Liu Changming , Liu Jue , Yang Hanchun , Jiang Ping , Zhou Jiyong
Published: March 2018

Apoptosis is an essential strategy of host defense responses and is used by viruses to maintain their life cycles. However, the apoptotic signals involved in virus replication are poorly known. In the present study, we report the molecular mechanism of apoptotic induction by the viral protein ORF4, a newly identified viral protein of porcine circovirus type 2 (PCV2). Apoptosis detection revealed not only that the activity of caspase-3 and -9 is increased in PCV2-infected and ORF4-transfected cells but also that cytochrome
c
release from the mitochondria to the cytosol is upregulated. Subsequently, ORF4 protein colocalization with adenine nucleotide translocase 3 (ANT3) was observed using structured illumination microscopy. Moreover, coimmunoprecipitation and pulldown analyses confirmed that the ORF4 protein interacts directly with mitochondrial ANT3 (mtANT3). Binding domain analysis further confirmed that N-terminal residues 1 to 30 of the ORF4 protein, comprising a mitochondrial targeting signal, are essential for the interaction with ANT3. Knockdown of
ANT3
markedly inhibited the apoptotic induction of both ORF4 protein and PCV2, indicating that ANT3 plays an important role in ORF4 protein-induced apoptosis during PCV2 infection. Taken together, these data indicate that the ORF4 protein is a mitochondrial targeting protein that induces apoptosis by interacting with ANT3 through the mitochondrial pathway.

IMPORTANCE
The porcine circovirus type 2 (PCV2) protein ORF4 is a newly identified viral protein; however, little is known about its functions. Apoptosis is an essential strategy of the host defense response and is used by viruses to maintain their life cycles. In the present study, we report the molecular mechanism of the apoptosis induced by the ORF4 protein. The ORF4 protein contains a mitochondrial targeting signal and is an unstable protein that is degraded by the proteasome-dependent pathway. Viral protein ORF4 triggers caspase-3- and -9-dependent cellular apoptosis in mitochondria by directly binding to ANT3. We conclude that the ORF4 protein is a mitochondrial targeting protein and reveal a mechanism whereby circovirus recruits ANT3 to induce apoptosis.
A Vaccine Platform against Arenaviruses Based on a Recombinant Hyperattenuated Mopeia Virus Expressing Heterologous Glycoproteins
Authors: Carnec Xavier , Mateo Mathieu , Page Audrey , Reynard Stéphanie , Hortion Jimmy , Picard Caroline , Yekwa Elsie , Barrot Laura , Barron Stéphane , Vallve Audrey , Raoul Hervé , Carbonnelle Caroline , Ferron François , Baize Sylvain
Published: March 2018

Several Old World and New World arenaviruses are responsible for severe endemic and epidemic hemorrhagic fevers, whereas other members of the
Arenaviridae
family are nonpathogenic. To date, no approved vaccines, antivirals, or specific treatments are available, except for Junín virus. However, protection of nonhuman primates against Lassa fever virus (LASV) is possible through the inoculation of the closely related but nonpathogenic Mopeia virus (MOPV) before challenge with LASV. We reasoned that this virus, modified by using reverse genetics, would represent the basis for the generation of a vaccine platform against LASV and other pathogenic arenaviruses. After showing evidence of exoribonuclease (ExoN) activity in NP of MOPV, we found that this activity was essential for multiplication in antigen-presenting cells. The introduction of multiple mutations in the ExoN site of MOPV NP generated a hyperattenuated strain (MOPV
ExoN6b
) that is (i) genetically stable over passages, (ii) has increased immunogenic properties compared to those of MOPV, and (iii) still promotes a strong type I interferon (IFN) response. MOPV
ExoN6b
was further modified to harbor the envelope glycoproteins of heterologous pathogenic arenaviruses, such as LASV or Lujo, Machupo, Guanarito, Chapare, or Sabia virus in order to broaden specific antigenicity while preserving the hyperattenuated characteristics of the parental strain. Our MOPV-based vaccine candidate for LASV, MOPEVAC
LASV
, was used in a one-shot immunization assay in nonhuman primates and fully protected them from a lethal challenge with LASV. Thus, our hyperattenuated strain of MOPV constitutes a promising new live-attenuated vaccine platform to immunize against several, if not all, pathogenic arenaviruses.

IMPORTANCE
Arenaviruses are emerging pathogens transmitted to humans by rodents and responsible for endemic and epidemic hemorrhagic fevers of global concern. Nonspecific symptoms associated with the onset of infection make these viruses difficult to distinguish from other endemic pathogens. Moreover, the unavailability of rapid diagnosis in the field delays the identification of the virus and early care for treatment and favors spreading. The vaccination of exposed populations would be of great help to decrease morbidity and human-to-human transmission. Using reverse genetics, we generated a vaccine platform for pathogenic arenaviruses based on a modified and hyperattenuated strain of the nonpathogenic Mopeia virus and showed that the Lassa virus candidate fully protected nonhuman primates from a lethal challenge. These results showed that a rationally designed recombinant MOPV-based vaccine is safe, immunogenic, and efficacious in nonhuman primates.
Countdown for UK Child Survival 2017: mortality progress and targets
Authors: Viner Russell M , Ward Joseph L , Wolfe Ingrid
Published: March 2018

Background

The Countdown for UK Child Survival tracks recent UK child mortality trends and makes recommendations for improvement.

Methods

We used data from the WHO World Mortality Database to calculate mortality from 1970 to 2014 for 0–19 year olds in the UK and a comparable group of wealthy countries (the EU15+). We used Poisson regression models to assess the significance of apparent differences. We extrapolated model coefficients to estimate future disparites between the UK and the EU15+ to 2030. We proposed goals and intermediate indicators to track UK mortality in keeping with the UN Sustainable Development Goals.

Results

UK infant mortality continues to track in the worst decile of EU15+ mortality with 1–4 year mortality in the worst quartile. Annual reductions in total UK mortality have been significantly lower than the EU15+ since 1990 for infant, postneonatal and 1–4 year mortality. If current trends persist, by 2030 UK infant mortality and 1–4 year mortality could be respectively 180% and 145% of EU15+ median mortality. UK non-communicable disease (NCD) mortality among 1–4 years and 15–19 years persists in the worst quartile. UK injury mortality continues in the best quartile. A framework of goals and indicators for UK child survival and health is presented.

Discussion

UK mortality among under 10 years of age continues to diverge from the EU15+ median, and UK NCD mortality remains persistently poor. We propose a set of goals to improve UK childhood survival by 2030 and an annual Countdown mechanism to monitor progress towards these targets.
Drug-induced movement disorder and confusion associated with duloxetine
Authors: Siddiqui Sarah Hasan , Memon Nadeem Ahmed , Shanker Ravi
Published: March 2018

A 60-year-old woman with major depressive disorder, developed high blood pressure, confusion and dyskinesias of face, neck and jaw, following an increase in her dose of duloxetine. Routine blood tests including toxic, infective and metabolic workup were unremarkable. Cerebrospinal fluid analysis and electroencephalogram were also normal. MRI brain showed bilaterally symmetrical diffusion-restricted areas in deep cerebral white matter. Duloxetine was held on suspicion of drug adverse effect. She had complete resolution of symptoms within 48 hours and resolution of MRI brain changes over 6 weeks. Serotonin norepinephrine reuptake inhibitors such as duloxetine may have the potential to cause drug-induced movement disorders, confusion and high blood pressure and should be used cautiously especially in elderly.
Aortic elongation part II: the risk of acute type A aortic dissection
Authors: Heuts Samuel , Adriaans Bouke P , Gerretsen Suzanne , Natour Ehsan , Vos Rein , Cheriex Emile C , Crijns Harry J G M , Wildberger Joachim E , Maessen Jos G , Schalla Simon , Sardari Nia Peyman
Published: March 2018

Objectives

Prophylactic surgery for prevention of acute type A aortic dissection (ATAAD) is reserved for patients with an ascending aortic aneurysm ≥55 mm. Identification of additional risk predictors is warranted since over 70% of patients presenting with ATAAD have a non-dilated aorta or an aneurysm that would not have met the diameter criterion for preventative surgery. Aim of the study was to evaluate ascending aortic elongation as a risk factor for ATAAD and to compare aortic lengths between ATAAD patients and healthy controls.

Methods

Aortic lengths and diameters of ATAAD patients were measured on three-dimensional modelled computed tomography and adjusted to predissection dimensions in this cross-sectional single-centre study. Logistic regression was used to evaluate the relation between ATAAD and aortic dimensions. Lengths of different aortic segments were compared with a healthy control group using propensity score matching.

Results

Two-hundred and fifty patients were included in the study (ATAAD, n=40; controls, n=210). Ascending aortic length and diameter proved to be independent predictors for ATAAD (OR=5.3, CI 2.5 to 11.4, p<0.001 and OR=8.6, CI 2.4 to 31.0, p=0.001). Eighty patients were matched based on propensity scores (ATAAD n=40, controls n=40). The ascending aorta was longer and more dilated in ATAAD patients compared with healthy controls (78.6±8.8 mm vs 68.9±7.2 mm, p<0.001, 34.4 mm ±3.2. vs 39.4 mm ±5.7, p<0.001, respectively). No differences were found in lengths of the aortic arch and descending aorta.

Conclusions

Ascending aortic length could serve as an independent predictor for ATAAD. Future studies addressing indications for prophylactic surgery should also investigate aortic length.
Biomarkers of chondrosarcoma
Authors: Jeong Wonju , Kim Ha-Jeong
Published: March 2018

Clinical outcome prediction is major concern to patients with cancer. Various molecular markers in various carcinomas have been identified in the past few decades. However, accurate predictors in chondrosarcoma have not been developed, even though chondrosarcoma is the second most common primary bone tumour. Chondrosarcoma is the cartilage-forming malignancy and shows a wide spectrum of clinicopathological behaviours. The majority of chondrosarcoma grows slowly and rarely metastasises, and adequate surgery leads to a good prognosis. However, wide surgical excision is acquired in high-grade chondrosarcoma, because this tumour is highly resistant to chemotherapy and radiotherapy. To decide best therapy, accurate diagnostic markers are also necessary in chondrosarcoma. It is reported that angiogenesis and lymphangiogenesis increase by chondrosarcoma staging, and they are promoted by leptin and adiponectin. Several microRNAs to regulate vascular endothelial growth factor (VEGF)-A and VEGF-C are also reported. Alpha-methylacyl-CoA racemase and periostin are proposed as new biomarkers for differential diagnosis of enchondroma and chondrosarcoma. This review summarises that chondrosarcoma diagnostic markers are currently reported.
Alteration ofDACH1methylation patterns in lung cancer contributes to cell proliferation and migration
Authors: Feng Yongjie , Wang Lin , Wang Mingyong
Published: March 2018

Lung cancer is the most common cause of cancer-related death. Non-small cell lung cancer (NSCLC) accounts for 80%–85% of total lung cancer cases. Dachshund homolog 1 (DACH1), is a protein encoded by the DACH1 gene in humans. DACH1 inhibits lung adenocarcinoma invasion and tumor growth but has a lower expression in NSCLC. To investigate the mechanisms of decreased DACH1 expression, its DNA methylation patterns were investigated. The results showed a higher methylation rate in NSCLC compared with the adjacent normal lung tissues. Cell transfection experiments showed that increased methylation impaired transcription factor transactivation. In vivo demethylation treatment and overexpression of DACH1 increased apoptosis and decreased migration and invasion in NSCLC A549 cells. Our research provides new insight into NSCLC pathogenesis and identifies a new therapeutic target.
Field performance of a peat railway subgrade reinforced with helical screw piles
Authors: Wheeler Lisa N. , Hendry Michael T. , Take W. Andy , Hoult Neil A.
Published: March 2018

Rail tracks on peat subgrades can experience significant deflections, some of which have led to derailments. A potential ground stabilization strategy is to use screw piles to reduce rail displacements; however, limited research has been undertaken to investigate the effect of these piles and their performance under cyclic train loading. A field site was instrumented and monitored before and after screw pile installation. The piles were instrumented with strain gauges, piezometers were installed in the peat, and high-speed cameras were used to measure track and subgrade displacements. The load carried by each instrumented pile was approximately 50–60 kN 3 weeks after installation, but reduced to approximately 30 kN after 6 months. Although 1 year’s worth of piezometric data were collected before installation of the piles, it is difficult to conclusively attribute the changes in pore pressures to the piles, particularly because the piezometric data collected after the pile installation were only available for the 7 months that exhibit the period of greatest seasonal fluctuations. The track support system deformations showed no significant difference pre- and post-pile installation. Therefore, based on the monitoring data at this site, it appears that the designed transfer of load from the ties to the piles through arching within the ballast layer was not realized.
Influence of agricultural intensification on prey availability and nestling diet in Tree Swallows (Tachycineta bicolor)
Authors: Bellavance V. , Bélisle M. , Savage J. , Pelletier F. , Garant D.
Published: March 2018

Over the last decades, aerial insectivorous birds have been declining in both North America and Europe. Those declines have been hypothetically attributed to a decrease in prey availability caused by agricultural intensification, but empirical evidence remains scarce. Here, we quantify the effect of landscape composition on the abundance and diversity of potential prey of Tree Swallows (Tachycineta bicolor (Vieillot, 1808)) and on nestling diet in southern Quebec, Canada. We collected food boluses from nestlings and compared their composition with spatiotemporally corresponding samples from traps on farms distributed along a gradient of agricultural intensification. The diet of nestlings was mostly composed of Diptera, both in biomass and abundance, but by mid-June, these decreased with increasing proportions of intensively cultivated crops within 500 m of the nests. Trap catches for Diptera and all arthropods combined followed the same trends. Yet, the associations between Diptera subgroups (Nematocera, non-schizophoran Brachycera, Schizophora (Calyptratae), and Schizophora (Acalyptratae)) and landscape composition differed between traps and boluses, suggesting that prey selection was altered by agricultural intensification. Our results suggest that agriculture can alter the availability of preferred prey for aerial insectivores, and further studies should evaluate the impact of prey availability to explain the decline of aerial insectivores.
Strong uniqueness polynomials of degree 6 and unique range sets for powers of meromorphic functions
Authors: Khoai Ha Huy , An Vu Hoai , Lai Nguyen Xuan
Published: March 2018

We investigate the uniqueness problems for meromorphic functions with higher multiplicities of zeros and poles. As a consequence, we present a class of strong uniqueness polynomials for meromorphic functions (SUPM) of degree [Formula: see text]. We also proved that there exist the sets [Formula: see text] of seven elements such that for arbitrary two meromorphic functions [Formula: see text] and [Formula: see text], the condition [Formula: see text] with [Formula: see text] implies [Formula: see text] where [Formula: see text] is a root of unity of degree [Formula: see text]
DETERMINANTS OF AGGLOMERATION IN KOREAN MANUFACTURING INDUSTRIES
Authors: CHUNG EUI-CHUL , LEE BUN SONG , CHO CHANHO
Published: March 2018

Despite accumulated findings on the effects of agglomeration on productivity of manufacturing industries in Korea, little is known about the determinants of agglomeration. Employing an approach similar to Rosenthal and Strange ( 2001 ) [Rosenthal, S and W Strange (2001). The determinants of agglomeration. Journal of Urban Economics, 50(2), 191–229.], but using a different agglomeration index, this study examines whether the three microfoundations of agglomeration economies are important to the geographical concentration of Korean manufacturing industries. While estimation results generally confirm that labor market pooling, input sharing and knowledge spillovers contribute to agglomeration, we found some differences with the previous literature. First, non-manufactured inputs are more influential on agglomeration than manufactured inputs. Secondly, aggregate innovation activities, rather than their share of shipments, are a better measure of knowledge spillovers to explain agglomeration. Thirdly, agglomeration of newly established firms is also influenced by the Marshallian externalities with labor market pooling having a stronger and consistent effect. These results are robust to instrumental variables estimation to control for endogeneity related to knowledge spillovers and labor market pooling.
Beta-spectrum shapes of forbidden β decays
Authors: Kostensalo Joel , Suhonen Jouni
Published: March 2018

The neutrinoless [Formula: see text] decay of atomic nuclei continues to attract fervent interest due to its potential to confirm the possible Majorana nature of the neutrino, and thus the nonconservation of the lepton number. At the same time, the direct dark matter experiments are looking for weakly interacting massive particles (WIMPs) through their scattering on nuclei. The neutrino-oscillation experiments on reactor antineutrinos base their analyses on speculations of [Formula: see text]-spectrum shapes of nuclear decays, thus leading to the notorious “reactor antineutrino anomaly.” In all these experimental efforts, one encounters the problem of [Formula: see text]-spectrum shapes of forbidden [Formula: see text] decays, either as unwanted backgrounds or unknown components in the analyses of data. In this work, the problem of spectrum shapes is discussed and illustrated with a set of selected examples. The relation of the [Formula: see text]-spectrum shapes to the problem of the effective value of the weak axial-vector coupling strength [Formula: see text] and the enhancement of the axial-charge matrix element is also pointed out.
The art of the state
Authors: Fewster Christopher J.
Published: March 2018

Quantum field theory (QFT) on curved spacetimes lacks an obvious distinguished vacuum state. We review a recent no-go theorem that establishes the impossibility of finding a preferred state in each globally hyperbolic spacetime, subject to certain natural conditions. The result applies in particular to the free scalar field, but the proof is model-independent and therefore of wider applicability. In addition, we critically examine the recently proposed “SJ states”, that are determined by the spacetime geometry alone, but which fail to be Hadamard in general. We describe a modified construction that can yield an infinite family of Hadamard states, and also explain recent results that motivate the Hadamard condition without direct reference to ultra-high energies or ultra-short distance structure.
Gravitational coupling and the cosmological constant
Authors: Bisabr Yousef
Published: March 2018

We deal with a dynamical mechanism in which a large cosmological constant, as suggested by inflationary scenarios, decays due to expansion of the universe. This mechanism has its origin in the gravitational coupling of the vacuum density. We assume that the vacuum couples anomalously to gravity that is the metric tensor that appears the gravitational part is not the same as that appears the matter part as suggested by weak equivalence principle. Instead, the two metric tensors are taken to be conformally related. We show that this provides a dynamical mechanism which works during expansion of the universe. We also consider some observational consequences of such a gravitational model.
Anisotropic strange star with Tolman V potential
Authors: Shee Dibyendu , Deb Debabrata , Ghosh Shounak , Ray Saibal , Guha B. K.
Published: March 2018

In this paper, we present a strange stellar model using Tolman [Formula: see text]-type metric potential employing simplest form of the MIT bag equation of state (EOS) for the quark matter. We consider that the stellar system is spherically symmetric, compact and made of an anisotropic fluid. Choosing different values of [Formula: see text] we obtain exact solutions of the Einstein field equations and finally conclude that for a specific value of the parameter [Formula: see text], we find physically acceptable features of the stellar object. Further, we conduct different physical tests, viz., the energy condition, generalized Tolman–Oppeheimer–Volkoff (TOV) equation, Herrera’s cracking concept, etc., to confirm the physical validity of the presented model. Matching conditions provide expressions for different constants whereas maximization of the anisotropy parameter provides bag constant. By using the observed data of several compact stars, we derive exact values of some of the physical parameters and exhibit their features in tabular form. It is to note that our predicted value of the bag constant satisfies the report of CERN-SPS and RHIC.
MILLING FORCE AND SURFACE TOPOGRAPHY OF Ti-6Al-4V TITANIUM ALLOY CLADDED BY THE LASER
Authors: WANG TAO , LI YANG , LIU JIAQI , QIN LINGCHAO , WANG NING , ZHANG LIFENG , WANG HAO , LI ZHAN
Published: March 2018

After the damaged blade is repaired by laser cladding, the quality of the recontouring by milling determines its working performance in reservice. Ti-6Al-4V, titanium alloy, commonly used as the material of manufacturing aero-engine blades, is selected as the experiment material. Laser cladding technology is used to prepare a cladding layer, and milling experiments are carried out on the cladding layer. The effects of milling process parameters on the milling force, roughness, and surface topography are studied. The results show that when the milling speed ([Formula: see text]) increases to 50[Formula: see text]m/min, the milling force and roughness ([Formula: see text]) reach the maximum and at this moment the surface topography is the worst. Afterwards, with an increase in [Formula: see text], both the milling force and [Formula: see text] decrease in proportion, and the surface topography also becomes better. As the feed per tooth ([Formula: see text]) increases, the milling force and [Formula: see text] also increase. However, the increasing trend gradually slows down. After [Formula: see text] increases to 0.08[Formula: see text]mm/z, the milling force and [Formula: see text] almost no longer increase and the surface topography remains almost unchanged. With an increase in milling width ([Formula: see text]), the milling force and [Formula: see text] increase on the whole. But while [Formula: see text] increases from 0.4[Formula: see text]mm to 0.8[Formula: see text]mm, the milling force and [Formula: see text] increase very slowly. When [Formula: see text] reaches over 0.8[Formula: see text]mm, the milling force and [Formula: see text] increase rapidly again. As [Formula: see text] changes, the surface topography changes according to the milling force and roughness. On this basis, it is found that while machining a laser cladding layer, the milling force directly affects the surface roughness and topography. Therefore, by adjusting [Formula: see text], [Formula: see text], and [Formula: see text], one can obtain the small milling force and good milling surface of the laser cladding TC4 layer.
LOW-TEMPERATURE NITRIDING BEHAVIOR OF COMPRESSIVE DEFORMED AISI 316Ti AUSTENITIC STAINLESS STEELS
Authors: KAHRAMAN FATIH , GENÇER GÖKÇE MEHMET , KAHRAMAN AYÇA D. , YOLCU COŞKUN , KAHRAMAN HAYDAR
Published: March 2018

The effects of compressive cold deformation under the quasi-static loads on the nitride formation, nitride layer growth and surface hardness properties were researched in this study. Martensite structure did not form in AISI 316Ti stainless steel as a result of quasi-static deformation. Diffusion layer did not form in all nitrided samples. Both the deformed and undeformed samples have only compound layer on the surfaces at the low-temperature nitriding conditions (400∘C, 7[Formula: see text]h). According to the X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS) and electron probe microanalysis (EPMA) results, S-phase and chromium nitride (CrN) were formed in the compound layers of the deformed samples. However, CrN did not form in the compound layer of the undeformed sample. The optical microscope (OM) results showed that the compressive cold deformation increased the nitrogen diffusion rate and led to thicker nitrided layer than the undeformed sample under the same plasma-nitriding conditions. All nitrided layers presented higher microhardness values ([Formula: see text][Formula: see text]HV) when compared with the untreated sample hardness. It was also verified that the deformation amount did not affect significantly the nitrided layer hardness.
TEM AND FESEM ANALYSIS OF DISSIMILAR JOINTS OF INCOLOY 800 HT AND P91 STEEL ON GTAW PROCESS
Authors: LAKSHMANAN V. , SATHIYA P.
Published: March 2018

The present paper investigates the dissimilar joining of Incoloy 800 HT and P91 steel using gas tungsten arc welding process. Welding was carried out using two filler materials, namely, Inconel 82 and 9CrMoV-Nb. Welding speed, current and voltage were considered as input parameters. Microhardness, tensile strength and impact strength were measured as performance characteristics. Metallurgical aspects of dissimilar welds were analyzed on the basis of microstructure obtained by using optical microscope, high-resolution field emission scanning electron microscopy and transmission electron microscopy. The ferrite content was measured by using feritscope, and the elemental analysis was carried out with the help of X-ray energy dispersive spectrometer. It was found that the 9CrMoV-Nb filler material produced dissimilar weld with better mechanical properties than the dissimilar weld produced using Inconel 82 filler material.
FORCE CHARACTERISTICS AND EFFECTIVE STOPPING UPON THE ABDOMINAL WALL IS PENETRATED OUT BY TROCAR DURING LAPAROSCOPIC SURGERY
Authors: SUN JUNPENG , TADANO KOTARO
Published: March 2018

Overshooting during trocar insertion may injury patient viscera and arteries or even lead to death. It has been extensively cited as a kind of common medical negligence. Hence, this paper investigated the force characteristics during a trocar inserted into the abdominal wall and developed strategies for effective stopping upon the trocar penetrated out of the abdominal wall. First, an experimental platform with two degrees of freedom was assembled. Second, two insertion methods were compared and the insertion forces using three types of trocars were measured respectively. Subsequently, we interpreted the force characteristics in terms of insertion principle and the abdominal structure. And based on the force characteristics, we generated two algorithms for the two insertion methods, which can be utilized to stop inserting effectively upon the trocar penetrated out of the abdominal wall. Finally, we evaluated the merits and demerits of the two algorithms. This paper proposed the interpretation of force characteristics during trocar insertion and achieved effective stopping to avoid overshooting. It provides foundations for the development of automatic trocar insertion device in the future.
DELINEATION OF CALCIUM DIFFUSION IN ALZHEIMERIC BRAIN
Authors: DAVE DEVANSHI D. , JHA BRAJESH KUMAR
Published: March 2018

Under the widespread umbrella of dementia, Alzheimer’s disease is the most common form of dementia. Most of the aged people are suffering from Alzheimer’s disease around the world. The reasons for the same are not known in detail and thus various experimental and computational attempts need to be carried out. Calcium, being a second messenger has an immense role in transformation of information. This transformation takes place in the form of signaling in which several parameters play an active role. In present work, an attempt has been made to describe the effect of calcium signaling in nerve cells for Alzheimer’s disease. Here, parameters like advection diffusion and buffering are taken into consideration to visualize the effects of the same on cytosolic calcium concentration. This physiological process is modeled two dimensionally and solved analytically. Laplace and similarity transforms are employed to obtain the desired results. The results are simulated and graphically plotted using MATLAB. The known fact that the higher concentration of calcium has adverse effects on the cell which may result into progression of AD is considered as a lantern in enlightening the physiology of Alzheimer’s disease.
FAHPSort: A Fuzzy Extension of the AHPSort Method
Authors: Krejčí Jana , Ishizaka Alessio
Published: March 2018

Analytic Hierarchy process (AHP) is a powerful method belonging to the full aggregation family of multi-criteria decision-making methods based on pairwise comparisons of objects. Since the information about the problem is usually not complete in real decision-making problems, it is difficult to express precisely the preferences on pairs of compared objects. This problem has been handled in the literature by introducing fuzziness into AHP. However, neither AHP nor its fuzzy extensions can deal with sorting decision-making problems, which form a significant part of decision-making problems. This paper presents the FAHPSort method — a fuzzy extension of the AHPSort method, which is an adaptation of the AHP method for sorting decision-making problems. The FAHPSort method handles the vagueness in the meaning of linguistic terms expressing the intensity of preference of one object over another one. Key properties of the FAHPSort method are described in the paper, and the method is illustrated in a decision-making problem.
New structural conditions on decay property with regularity-loss for symmetric hyperbolic systems with non-symmetric relaxation
Authors: Ueda Yoshihiro , Duan Renjun , Kawashima Shuichi
Published: March 2018

This paper is concerned with the weak dissipative structure for linear symmetric hyperbolic systems with relaxation. The authors of this paper had already analyzed the new dissipative structure called the regularity-loss type in [Y. Ueda, R. Duan and S. Kawashima, Decay structure for symmetric hyperbolic systems with non-symmetric relaxation and its application, Arch. Ration. Mech. Anal. 205 (2012) 239–266]. Compared with the dissipative structure of the standard type in [T. Umeda, S. Kawashima and Y. Shizuta, On the devay of solutions to the linearized equations of electro-magneto-fluid dynamics, Japan J. Appl. Math. 1 (1984) 435–457; Y. Shizuta and S. Kawashima, Systems of equations of hyperbolic-parabolic type with applications to the discrete Boltzmann equation, Hokkaido Math. J. 14 (1985) 249–275], the regularity-loss type possesses a weaker structure in the high-frequency region in the Fourier space. Furthermore, there are some physical models which have more complicated structure, which we discussed in [Y. Ueda, R. Duan and S. Kawashima, Decay structure of two hyperbolic relaxation models with regularity loss, Kyoto J. Math. 57(2) (2017) 235–292]. Under this situation, we introduce new concepts and extend our previous results developed in [Y. Ueda, R. Duan and S. Kawashima, Decay structure for symmetric hyperbolic systems with non-symmetric relaxation and its application, Arch. Ration. Mech. Anal. 205 (2012) 239–266] to cover those complicated models.
Ruthenium and manganese metalloporphyrins modified screen-printed electrodes for bio-relevant electroactive targets
Authors: Carbone Marilena , Micheli Laura , Limosani Francesca , Possanza Fabio , Abdallah Yassmine , Tagliatesta Pietro
Published: March 2018

Ruthenium(II) 5-(4[Formula: see text]-sulfanylmethylphenyl)-10,15,20-triphenylporphyrin (Ru-TPP-SH) and manganese(III) 5-(4[Formula: see text]-sulfanylmethylphenyl)-10,15,20-triphenylporphyrin (Mn-TPP-SH) were synthesized, spectroscopically characterized and drop casted to modify screen-printed electrodes (SPEs). The modified SPEs were then tested against the redox target [Fe(CN)6][Formula: see text] in comparison with the bare SPE and SPE modified with the free porphyrin. The best performing one, [Formula: see text]. Mn-TPP-SH was used for the electrochemical detection of 1,4–benzoquinone, serotonin, caffeic and ascorbic acids, the latter also in association with uric acid, showing good electrocatalytic properties. The tunability of the metal-TPP-SH through the choice of the coordinating metal, the drop casting conditions and possible further functionalization make this type of porphyrin a good candidate for further developments of porphyrin-modified SPEs.
Characteristics Analysis for Nanosoldering with Atomic Force Microscope
Authors: Liu Zenglei , Gao Ailian , Xie Shuangxi , Jiao Niandong , Liu Lianqing
Published: March 2018

Field-emission deposition of atomic force microscope (AFM) can be used to fabricate nanopads, and therefore has potential applications in soldering nanodevices. However, the soldering effects are hard to verify because the soldering pads are of nanoscale. This paper studied the electrical, thermal and mechanical characteristics of the deposited nanopads, in order to testify the soldering effects. For this purpose, first, a carbon nanotube field effect transistor (CNTFET) was soldered to see whether the conductivity of the transistor was improved. Next, the thermal performance of the nanopads were observed by heating them in an oven. Last, the nanopads were mechanically pushed by an AFM probe to test the physical connection between the nanopads and the substrate. Experimental results showed that the nanosoldering dramatically reduced the contact resistance of the transistor. Moreover, the nanopads could withstand high temperature and mechanical push. Consequently, field-emission deposition of the AFM promised a bright future in nanosoldering.