bluuebunny/crossref_metadata_2025 huggingface dataset:
Protective Role for Macrophages in Respiratory Francisella tularensis Infection
Authors: Steiner Donald J. , Furuya Yoichi , Jordan Michael B. , Metzger Dennis W.
Published: April 2017

Francisella tularensiscauses lethal pneumonia following infection of the lungs by targeting macrophages for intracellular replication; however, macrophages stimulated with interferon gamma (IFN-γ) can resist infectionin vitro. We therefore hypothesized that the protective effect of IFN-γ againstF. tularensisin vivorequires macrophages receptive to stimulation. We found that the lethality of pulmonaryF. tularensisLVS infection was exacerbated under conditions of alveolar macrophage depletion and in mice with a macrophage-specific defect in IFN-γ signaling (termed mice with macrophages insensitive to IFN-γ [MIIG mice]). We previously found that treatment with exogenous interleukin 12 (IL-12) protects againstF. tularensisinfection; this protection was lost in MIIG mice. MIIG mice also exhibited reduced neutrophil recruitment to the lungs following infection. Systemic neutrophil depletion was found to render wild-type mice highly sensitive to respiratoryF. tularensisinfection, and depletion beginning at 3 days postinfection led to more pronounced sensitivity than depletion beginning prior to infection. Furthermore, IL-12-mediated protection required NADPH oxidase activity. These results indicate that lung macrophages serve a critical protective role in respiratoryF. tularensisLVS infection. Macrophages require IFN-γ signaling to mediate protection, which ultimately results in recruitment of neutrophils to further aid in survival from infection.
The Legionella pneumophila Incomplete Phosphotransferase System Is Required for Optimal Intracellular Growth and Maximal Expression of PmrA-Regulated Effectors
Authors: Speiser Yariv , Zusman Tal , Pasechnek Anna , Segal Gil
Published: April 2017

The nitrogen phosphotransferase system (PTS
Ntr
) is a regulatory cascade present in many bacteria, where it controls different functions. This system is usually composed of three basic components: enzyme I
Ntr
(EI
Ntr
), NPr, and EIIA
Ntr
(encoded by the
ptsP
,
ptsO
, and
ptsN
genes, respectively). In
Legionella pneumophila
, as well as in many other
Legionella
species, the EIIA
Ntr
component is missing. However, we found that deletion mutations in both
ptsP
and
ptsO
are partially attenuated for intracellular growth. Furthermore, these two PTS
Ntr
components were found to be required for maximal expression of effector-encoding genes regulated by the transcriptional activator PmrA. Genetic analyses which include the construction of single and double deletion mutants and overexpression of wild-type and mutated forms of EI
Ntr
, NPr, and PmrA indicated that the PTS
Ntr
components affect the expression of PmrA-regulated genes via PmrA and independently from PmrB and that EI
Ntr
and NPr are part of the same cascade and require their conserved histidine residues in order to function. Furthermore, expression of the
Legionella micdadei
EII
Ntr
component in
L. pneumophila
resulted in a reduction in the levels of expression of PmrA-regulated genes which was completely dependent on the
L. pneumophila
PTS components and the
L. micdadei
EII
Ntr
conserved histidine residue. Moreover, reconstruction of the
L. pneumophila
PTS
in vitro
indicated that EI
Ntr
is phosphorylated by phosphoenolpyruvate (PEP) and transfers its phosphate to NPr. Our results demonstrate that the
L. pneumophila
incomplete PTS
Ntr
is functional and involved in the expression of effector-encoding genes regulated by PmrA.
The Rhomboid Protease GlpG Promotes the Persistence of Extraintestinal Pathogenic Escherichia coli within the Gut
Authors: Russell Colin W. , Richards Amanda C. , Chang Alexander S. , Mulvey Matthew A.
Published: April 2017

Extraintestinal pathogenic
Escherichia coli
(ExPEC) strains are typically benign within the mammalian gut but can disperse to extraintestinal sites to cause diseases like urinary tract infections and sepsis. As occupation of the intestinal tract is often a prerequisite for ExPEC-mediated pathogenesis, we set out to understand how ExPEC colonizes this niche. A screen using transposon sequencing (Tn-seq) was performed to search for genes within ExPEC isolate F11 that are important for growth in intestinal mucus, which is thought to be a major source of nutrients for
E. coli
in the gut. Multiple genes that contribute to ExPEC fitness in mucus broth were identified, with genes that are directly or indirectly associated with fatty acid beta-oxidation pathways being especially important. One of the identified mucus-specific fitness genes encodes the rhomboid protease GlpG.
In vitro
, we found that the disruption of
glpG
had polar effects on the downstream gene
glpR
, which encodes a transcriptional repressor of factors that catalyze glycerol degradation. Mutation of either
glpG
or
glpR
impaired ExPEC growth in mucus and on plates containing the long-chain fatty acid oleate as the sole carbon source. In contrast, in a mouse gut colonization model in which the natural microbiota is unperturbed, the disruption of
glpG
but not
glpR
significantly reduced ExPEC survival. This work reveals a novel biological role for a rhomboid protease and highlights new avenues for defining mechanisms by which ExPEC strains colonize the mammalian gastrointestinal tract.
Suppressors of dGTP Starvation in Escherichia coli
Authors: Itsko Mark , Schaaper Roel M.
Published: April 2017

dGTP starvation, a newly discovered phenomenon in which
Escherichia coli
cells are starved specifically for the DNA precursor dGTP, leads to impaired growth and, ultimately, cell death. Phenomenologically, it represents an example of nutritionally induced unbalanced growth: cell mass amplifies normally as dictated by the nutritional status of the medium, but DNA content growth is specifically impaired. The other known example of such a condition, thymineless death (TLD), involves starvation for the DNA precursor dTTP, which has been found to have important chemotherapeutic applications. Experimentally, dGTP starvation is induced by depriving an
E. coli
gpt optA1
strain of its required purine source, hypoxanthine. In our studies of this phenomenon, we noted the emergence of a relatively high frequency of suppressor mutants that proved resistant to the treatment. To study such suppressors, we used next-generation sequencing on a collection of independently obtained mutants. A significant fraction was found to carry a defect in the PurR transcriptional repressor, controlling
de novo
purine biosynthesis, or in its downstream
purEK
operon. Thus, upregulation of
de novo
purine biosynthesis appears to be a major mode of overcoming the lethal effects of dGTP starvation. In addition, another large fraction of the suppressors contained a large tandem duplication of a 250- to 300-kb genomic region that included the
purEK
operon as well as the
acrAB
-encoded multidrug efflux system. Thus, the suppressive effects of the duplications could potentially involve beneficial effects of a number of genes/operons within the amplified regions.

IMPORTANCE
Concentrations of the four precursors for DNA synthesis (2′-deoxynucleoside-5′-triphosphates [dNTPs]) are critical for both the speed of DNA replication and its accuracy. Previously, we investigated consequences of dGTP starvation, where the DNA precursor dGTP was specifically reduced to a low level. Under this condition,
E. coli
cells continued cell growth but eventually developed a DNA replication defect, leading to cell death due to formation of unresolvable DNA structures. Nevertheless, dGTP-starved cultures eventually resumed growth due to the appearance of resistant mutants. Here, we used whole-genome DNA sequencing to identify the responsible suppressor mutations. We show that the majority of suppressors can circumvent death by upregulating purine
de novo
biosynthesis, leading to restoration of dGTP to acceptable levels.
Do influenza and pneumococcal vaccines prevent community-acquired respiratory infections among older people with diabetes and does this vary by chronic kidney disease? A cohort study using electronic health records
Authors: McDonald Helen I , Thomas Sara L , Millett Elizabeth R C , Quint Jennifer , Nitsch Dorothea
Published: April 2017

Objective

We aimed to estimate the effectiveness of influenza and 23-valent pneumococcal polysaccharide vaccination on reducing the burden of community-acquired lower respiratory tract infection (LRTI) among older people with diabetes, and whether this varied by chronic kidney disease (CKD) status.

Research design and methods

We used linked UK electronic health records for a retrospective cohort study of 190 492 patients ≥65 years with diabetes mellitus and no history of renal replacement therapy, 1997–2011. We included community-acquired LRTIs managed in primary or secondary care. Infection incidence rate ratios were estimated using the Poisson regression. Pneumococcal vaccine effectiveness (VE) was calculated as (1−effect measure). To estimate influenza VE, a ratio-of-ratios analysis (winter effectiveness/summer effectiveness) was used to address confounding by indication. Final VE estimates were stratified according to estimated glomerular filtration rate and proteinuria status.

Results

Neither influenza nor pneumococcal vaccine uptake varied according to CKD status. Pneumococcal VE was 22% (95% CI 11% to 31%) against community-acquired pneumonia for the first year after vaccination, but was negligible after 5 years. In the ratio-of-ratios analysis, current influenza vaccination had 7% effectiveness for preventing community-acquired LRTI (95% CI 3 to 12). Pneumococcal VE was lower among patients with a history of proteinuria than among patients without proteinuria (p=0.04), but otherwise this study did not identify variation in pneumococcal or influenza VE by markers of CKD.

Conclusions

The public health benefits of influenza vaccine may be modest among older people with diabetes. Pneumococcal vaccination protection against community-acquired pneumonia declines swiftly: alternative vaccination schedules should be investigated.
Economic study of the value of expanding HCV treatment capacity in Germany
Authors: Sbarigia Urbano , Wirth Daniel , Van Nuys Karen , Huber Caroline , Brookmeyer Ron , Stahmeyer Jona , Krauth Christian
Published: April 2017

Background

Today's highly efficacious, low-toxicity interferon-free treatment regimens for chronic hepatitis C virus (HCV) can cure most patients with HCV in 12–24 weeks. The aim of this study was to understand how the introduction of shorter duration treatment regimens for HCV will impact the capacity for treatment and value to society.

Methods

A Markov model of HCV transmission and progression was constructed, incorporating nationally representative data on HCV prevalence, incidence and progression; mortality, treatment costs, medical expenditures, employment probabilities and disability payments in Germany. The model was stratified by HCV genotype and exposure route (1-time healthcare exposure, injection drug use and sexual activity). Treatment scenarios were based on German treatment guidelines and projected treatment capacity. The impact of different treatment scenarios on disease transmission and prevalence, quality-adjusted life years (QALYs), treatment costs, medical expenditures, employment and disability expenditures was calculated.

Results

Depending on their adoption profile, new treatment regimens and protocols introduced over the next several years will increase HCV treatment capacity in Germany by 8–30%, reducing disease transmission and prevalence, increasing QALYs and adding €94–310 million in discounted social value (QALYs plus medical savings net of treatment costs) over a 30-year horizon. Additional social value in the form of higher employment and lower disability would also result.

Conclusions

The introduction of shorter HCV treatment regimens and the resulting increased treatment capacity in Germany would result in large gains to society by reducing disease transmission and prevalence, resulting in longer, healthier, more productive lives for current and future generations.
Cute as candy: a qualitative study of perceptions of snus branding and package design among youth in Norway
Authors: Scheffels Janne , Lund Ingeborg
Published: April 2017

Objectives

Snus use has increased among youth in Norway in recent years and is now more prevalent than smoking. Concurrently, a range of new products and package designs have been introduced to the market. The aim of this study was to explore how youth perceive snus branding and package design, and the role, if any, of snus packaging on perceptions of appeal and harm of snus among youth.

Participants

Adolescent tobacco users and non-users (N=35) ages 15–17 years.

Design

We conducted interviews among 6 focus groups (each with 4–7 participants). Participants were shown snus packages with a variety of designs and with different product qualities (flavour additives, slim, regular, white and brown sachets) and group discussions focused on how they perceived packages and products. The focus group discussions were semistructured using a standard guide, and analysed thematically.

Results

The participants in the focus groups narrated distinct images of snus brands and associated user identities. Package design elements such as shapes, colours, images and fonts were described as guiding these perceptions. Packaging elements and flavour additives were associated with perceptions of product harm. The appeal of flavoured snus products and new types of snus sachets seemed to blend in with these processes, reinforcing positive attitudes and contributing to the creation of particular identities for products and their users.

Conclusions

The findings indicate that packaging is vital to consumer's identification with, and differentiation between, snus brands. In view of this, snus branding and packaging can be seen as fulfilling a similar promotional role as advertising messages: generating preferences and appeal.
Standards for Reporting Implementation Studies (StaRI): explanation and elaboration document
Authors: Pinnock Hilary , Barwick Melanie , Carpenter Christopher R , Eldridge Sandra , Grandes Gonzalo , Griffiths Chris J , Rycroft-Malone Jo , Meissner Paul , Murray Elizabeth , Patel Anita , Sheikh Aziz , Taylor Stephanie J C
Published: April 2017

Objectives

Implementation studies are often poorly reported and indexed, reducing their potential to inform the provision of healthcare services. The Standards for Reporting Implementation Studies (StaRI) initiative aims to develop guidelines for transparent and accurate reporting of implementation studies.

Methods

An international working group developed the StaRI guideline informed by a systematic literature review and e-Delphi prioritisation exercise. Following a face-to-face meeting, the checklist was developed iteratively by email discussion and critical review by international experts.

Results

The 27 items of the checklist are applicable to the broad range of study designs employed in implementation science. A key concept is the dual strands, represented as 2 columns in the checklist, describing, on the one hand, the implementation strategy and, on the other, the clinical, healthcare or public health intervention being implemented. This explanation and elaboration document details each of the items, explains the rationale and provides examples of good reporting practice.

Conclusions

Previously published reporting statements have been instrumental in improving reporting standards; adoption by journals and authors may achieve a similar improvement in the reporting of implementation strategies that will facilitate translation of effective interventions into routine practice.
Associations of moderate-to-vigorous-intensity physical activity and body mass index with glycated haemoglobin within the general population: a cross-sectional analysis of the 2008 Health Survey for England
Authors: Bakrania Kishan , Yates Thomas , Edwardson Charlotte L , Bodicoat Danielle H , Esliger Dale W , Gill Jason M R , Kazi Aadil , Velayudhan Latha , Sinclair Alan J , Sattar Naveed , Biddle Stuart J H , Hamer Mark , Davies Melanie J , Khunti Kamlesh
Published: April 2017

Objectives

To investigate the associations of objectively measured moderate-to-vigorous-intensity physical activity (MVPA) and body mass index (BMI) with glycated haemoglobin (HbA1c) in a national sample of English adults.

Methods

The 2008 Health Survey for England data were used with 1109 participants aged ≥18 providing complete data. MVPA time was assessed using an accelerometer. Weighted linear regression models, adjusted for several confounders, quantified the associations between continuous measures of MVPA and BMI with HbA1c. Interaction analyses were implemented to observe whether the association of MVPA with HbA1c was modified by BMI or vice versa. Further weighted linear regression models examined the differences in HbA1c across four mutually exclusive categories of MVPA and BMI: (1) ‘physically active and non-obese’, (2) ‘physically active and obese’, (3) ‘physically inactive and non-obese’ and (4) ‘physically inactive and obese’. ‘Physically active’ was defined as: ≥150 min/week of MVPA. ‘Obese’ was defined as: BMI ≥30.0 kg/m2. A wide range of sensitivity analyses were also implemented.

Results

Every 30 min/day increment in MVPA was associated with a 0.7 mmol/mol (0.07% (p<0.001)) lower HbA1c level. Each 1 kg/m2increment in BMI was associated with a 0.2 mmol/mol (0.02% (p<0.001)) higher HbA1c level. The association of MVPA with HbA1c was stronger in obese individuals (−1.5 mmol/mol (−0.13% (p<0.001))) than non-obese individuals (−0.7 mmol/mol (−0.06% (p<0.001))); p=0.004 for interaction. The association of BMI with HbA1c remained stable across MVPA categories. Compared with individuals categorised as ‘physically inactive and obese’, only those categorised as ‘physically active and obese’ or ‘physically active and non-obese’ had lower HbA1c levels by 2.1 mmol/mol (0.19% (p=0.005)) and 3.5 mmol/mol (0.32% (p<0.001)), respectively. Sensitivity analyses indicated robustness and stability.

Conclusions

This study emphasises the importance of physical activity as a determinant of HbA1c, and suggests that the associations may be stronger in obese adults.
Prevalence and influencing factors of hepatitis B among a rural residential population in Zhejiang Province, China: a cross-sectional study
Authors: Yang Shigui , Ding Cheng , Cui Yuanxia , Wu Jie , Yu Chengbo , Chen Ping , Xu Kaijin , Deng Min , Li Yiping , Liu Juanjuan , Yin Pei , Ren Wen , Qiu Yan , Cao Qing , Zhou Yuqing , Yao Jun , Ruan Bing , Ren Jingjing , Li Lanjuan
Published: April 2017

Objectives

To reveal the prevalence and associated influencing factors of hepatitis B among a rural residential population in Zhejiang, China, in order to help develop specific control strategies.

Methods

We conducted a cross-sectional study among a rural residential population in Zhejiang, China. Stratified multistage cluster sampling was utilised in five districts; a structured questionnaire was used to collect the information such as age, gender, education, occupation, living status, and other health related information of the participants by trained local staff; and the hepatitis B virus (HBV) infection status of the participants was determined by the chemiluminescence immunoassay test. Univariate and multivariate analyses were applied to evaluate the influencing factors of HBV infection. The odds ratio of each related factor was assessed with or without adjustment separately.

Results

The mean age of the 16 601 participants (7881 males and 8720 females) who completed the survey was 40.28±19.47 years. The positive rate of hepatitis B surface antigen (HBsAg) was 4.04% (95% CI 3.74% to 4.35%), and 3.85% when standardised by age and gender. Univariate analysis showed that age, educational level, occupation, living status, history of hepatitis B examinations, history of blood transfusion, vaccination, family history, coastal living, and district were the potential influencing factors. Multivariate logistic regression indicated that occupation, living status, history of hepatitis B examinations, vaccination and district were the influencing factors. Undertaking a service-based tertiary industry job (ORa1.19, 95% CI 0.94 to 1.51) and non-single living (ORa2.84, 95% CI 2.17 to 3.70) might be risk factors, while vaccination (ORa0.43, 95% CI 0.34 to 0.53) and history of hepatitis B examinations (ORa0.71, 95% CI 0.48 to 1.03) were potential protective factors.

Conclusions

The prevalence of hepatitis B is at an intermediate epidemic level in a rural residential population in Zhejiang, China. Raising vaccination coverage, especially in adults, is a suitable strategy for the prevention and control of hepatitis B.
EUropean prospective cohort study onEnterobacteriaceaeshowing REsistance to CArbapenems (EURECA): a protocol of a European multicentre observational study
Authors: Gutiérrez-Gutiérrez Belén , Sojo-Dorado Jesús , Bravo-Ferrer José , Cuperus Nienke , de Kraker Marlieke , Kostyanev Tomislav , Raka Lul , Daikos George , Feifel Jan , Folgori Laura , Pascual Alvaro , Goossens Herman , O'Brien Seamus , Bonten Marc J M , Rodríguez-Baño Jesús
Published: April 2017

Introduction

The rapid worldwide spread of carbapenem-resistantEnterobacteriaceae(CRE) constitutes a major challenge. The aim of the EUropean prospective cohort study onEnterobacteriaceaeshowing REsistance to CArbapenems (EURECA), which is part of the Innovative Medicines Initiative Joint Undertaking (IMI JU) funded COMBACTE-CARE project, is to investigate risk factors for and outcome determinants of CRE infections to inform randomised clinical trial designs and to provide a historical cohort that could eventually be used for future comparisons with new drugs targeting CRE.

Methods

A multicentre (50 sites), multinational (11 European countries), analytical observational project was designed, comprising 3 studies. The aims of study 1 (a prospective cohort study) include characterising the features, clinical management and outcomes of hospitalised patients with intra-abdominal infection, pneumonia, complicated urinary tract infections and bloodstream infections caused by CRE (202 patients in each group). The main outcomes will be 30-day all-cause mortality and clinical response. Study 2 (a nested case–control study) will identify the risk factors for target infections caused by CRE; 248 selected patients from study 1 will be matched with patients with carbapenem-susceptibleEnterobacteriaceae(1:1) and with hospitalised patients (1:3) and will provide a historical cohort of patients with CRE infections. Study 3 (a matched cohort study) will follow patients in study 2 in order to assess mortality, length of stay and hospital costs associated with CRE. All patients will be followed for 30 days. Different, up-to-date statistical methods will be applied to come to unbiased estimates for all 3 studies.

Ethics and dissemination

Before-study sites will be initiated, approval will be sought from appropriate regulatory agencies and local Ethics Committees of Research or Institutional Review Boards (IRBs) to conduct the study in accordance with regulatory requirements. This is an observational study and therefore no intervention in the diagnosis, management or treatment of the patients will be required on behalf of the investigation. Any formal presentation or publication of data collected from this study will be considered as a joint publication by the participating physician(s) and will follow the recommendations of the International Committee of Medical Journal Editors (ICMJE) for authorship.

Trial registration number

NCT02709408.
Home or hospital for people with dementia and one or more other multimorbidities: What is the potential to reduce avoidable emergency admissions? The HOMEWARD Project Protocol
Authors: Voss S , Black S , Brandling J , Buswell M , Cheston R , Cullum S , Kirby K , Purdy S , Solway C , Taylor H , Benger J
Published: April 2017

Introduction

Older people with multimorbidities frequently access 999 ambulance services. When multimorbidities include dementia, the risk of ambulance use, accident and emergency (A&E) attendance and hospital admission are all increased, even when a condition is treatable in the community. People with dementia tend to do poorly in the acute hospital setting and hospital admission can result in adverse outcomes. This study aims to provide an evidence-based understanding of how older people living with dementia and other multimorbidities are using emergency ambulance services. It will also provide evidence of how paramedics make decisions about taking this group of patients to hospital, and what resources would allow them to make more person-focused decisions to enable optimal patient care.

Methods and analysis

Phase 1: retrospective data analysis: quantitative analysis of ambulance service data will investigate: how often paramedics are called to older people with dementia; the amount of time paramedics spend on scene and the frequency with which these patients are transported to hospital.Phase 2: observational case studies: detailed case studies will be compiled using qualitative methods, including non-participant observation of paramedic decision-making, to understand why older people with multimorbidities including dementia are conveyed to A&E when they could be treated at home or in the community.Phase 3: needs analysis: nominal groups with paramedics will investigate and prioritise the resources that would allow emergency, urgent and out of hours care to be effectively delivered to these patients at home or in a community setting.

Ethics and dissemination

Approval for the study has been obtained from the Health Research Authority (HRA) with National Health Service (NHS) Research Ethics Committee approval for phase 2 (16/NW/0803). The dissemination strategy will include publishing findings in appropriate journals, at conferences and in newsletters. We will pay particular attention to dissemination to the public, dementia organisations and ambulance services.
Trends in paediatric asthma hospitalisations – differences between neighbouring countries
Authors: Kivistö Juho E , Protudjer Jennifer L P , Karjalainen Jussi , Bergström Anna , Korppi Matti
Published: April 2017

Paediatric asthma hospitalisation trends in Finland and Sweden over the past 10 years are unclear. We investigated the incidence of paediatric asthma hospitalisations in both countries from 2005 to 2014, using Finland's National Hospital Discharge Register and Sweden's National Patient Register which cover all hospitalisations in the respective countries. During the study period, the incidence of paediatric asthma hospitalisations decreased by 51% in Finland, but remained stable in Sweden. In both countries, asthma hospitalisations decreased over time among children aged 0–4 years, with unclear trends for older ages. The reasons for these intercountry differences are unclear, thus warranting future research.
Improving patients’ home cooking – A case series of participation in a remote culinary coaching program
Authors: Polak Rani , Pober David M. , Budd Maggi A. , Silver Julie K. , Phillips Edward M. , Abrahamson Martin J.
Published: April 2017

This case series describes and examines the outcomes of a remote culinary coaching program aimed at improving nutrition through home cooking. Participants (n = 4) improved attitudes about the perceived ease of home cooking (p < 0.01) and self-efficacy to perform various culinary skills (p = 0.02); and also improved in confidence to continue online learning of culinary skills and consume healthier food. We believe this program might be a viable response to the need for effective and scalable health-related culinary interventions.
Subsurface heterogeneity in the geological and hydraulic properties of the hummocky Paris Moraine, Guelph, Ontario
Authors: Arnaud Emmanuelle , McGill Michael , Trapp Andrew , Smith James E.
Published: April 2017

The advance and retreat of ice lobe margins of the Laurentide Ice Sheet formed moraines that are a prevalent feature throughout southwestern Ontario. In contrast to the well-studied stratified moraine complexes, recessional and end moraines have largely been ignored in the context of hydrogeological studies. Recent urban growth has led to development pressures on these moraines and a need to better understand their hydrogeology. This study presents data sets from the Paris Moraine near Guelph, Ontario, to examine its geomorphology, internal composition, and the corresponding hydraulic properties of these ice-marginal features. The moraine’s geomorphic elements were mapped using high-resolution Global Positioning System transects, aerial photograph analysis, and ground truthing. Nine continuous sediment cores were recovered to determine the nature and distribution of subsurface sedimentary units and their relation to the regional stratigraphic framework. Cores were described in detail using standard sedimentological techniques, and significant sediment heterogeneity was observed in cross sections. Grain-size analyses of over 150 samples provide site-specific estimates of saturated hydraulic conductivity. In addition, saturated hydraulic conductivity was measured on 104 samples using the falling head permeameter method. This study found that different scales of sediment heterogeneity occur across the moraine and the associated till plain and outwash. In contrast, the hydraulic conductivity varies much less. It is expected that certain sedimentary units at specific depths will impact groundwater flow at the centimetre to hundreds of metres scale, which is significant in environmental site assessments or for understanding contaminant hydrogeological problems.
Comparative bacterial community analysis in relatively pristine and anthropogenically influenced mangrove ecosystems on the Red Sea
Authors: Ullah Riaz , Yasir Muhammad , Khan Imran , Bibi Fehmida , Sohrab Sayed Sartaj , Al-Ansari Ahmed , Al-Abbasi Fahad , Al-Sofyani Abdulmohsin A. , Daur Ihsanullah , Lee Seon-Woo , Azhar Esam I.
Published: April 2017

Mangrove habitats are ecologically important ecosystems that are under severe pressure worldwide because of environmental changes and human activities. In this study, 16S rRNA gene amplicon deep-sequencing was used to compare bacterial communities in Red Sea mangrove ecosystems at anthropogenically influenced coastal sites with those at a relatively pristine island site. In total, 32 phyla were identified from the mangrove rhizospheres, with Proteobacteria predominating at each of the studied sites; however, the relative abundance was significantly decreased at the coastal sites (Mastorah, MG-MS; Ar-Rayis, MG-AR) compared with the pristine island site near Dhahban (MG-DBI). The phyla Actinobacteria, Firmicutes, Acidobacteria, Chloroflexi, Spirochetes, and Planctomycetes were present at a relative abundance of >1% at the MG-MS and MG-AR sites, but their concentration was <1% at the MG-DBI site. A total of 1659 operational taxonomic units (OTUs) were identified at the species level, and approximately 945 OTUs were shared across the different sampling sites. Multivariate principal coordinate data analysis separated the MG-DBI site from the MG-AR and MG-MS cluster. Specific bacterial taxa were enriched at each location, and in particular, the genera Pseudoalteromonas and Cobetia were predominantly identified in the MG-DBI site compared with the anthropogenically influenced coastal sites.
Passive control of deep cavity shear layer flow at subsonic speed
Authors: El Hassan Mouhammad , Keirsbulck Laurent
Published: April 2017

Passive control of the flow over a deep cavity at low subsonic velocity is considered in the present paper. The cavity length-to-depth aspect ratio is L/H = 0.2. particle image velocimetry (PIV) measurements characterized the flow over the cavity and show the influence of the control method on the cavity shear layer development. It is found that both the “cylinder” and the “shaped cylinder”, placed upstream from the cavity leading edge, result in the suppression of the aero-acoustic coupling and highly reduce the cavity noise. It should be noted that the vortical structures impinge at almost the same location near the cavity downstream corner with and without passive control. The present study allows to identify an innovative passive flow control method of cavity resonance. Indeed, the use of a “shaped cylinder” presents similar suppression of the cavity resonance as with the “cylinder” but with less impact on the cavity flow. The “shaped cylinder” results in a smaller shear layer growth than the cylinder. Velocity deficiency and turbulence levels are less pronounced using the “shaped cylinder”. The “cylinder” tends to diffuse the vorticity in the cavity shear layer and thus the location of the maximum vorticity is more affected as compared to the “shaped cylinder” control. The fact that the “shaped cylinder” is capable of suppressing the cavity resonance, despite the vortex shedding and the high frequency forcing being suppressed, is of high interest from fundamental and applied points of view.
Origin of singularity in Big Bang theory from zero point energy
Authors: Das Tapan
Published: April 2017

This paper presents a mathematical proposition based on zero point energy of the creation of singularity in the current Hot Bing Bang theory of the origin of the universe. The observable universe we live in and can see is finite and is defined by the speed of light. The entire universe is infinite and the observable universe is part of it. Zero point energy exists in the entire universe and at all frequencies up to the Planck frequency. Zero point energy was calculated by Planck. The Casimir effect, predicted by Hendrick Casimir, is caused by zero point energy and has been experimentally proven by S. Lamoreux and U. Mohideen. The author has mathematically calculated that the zero point energy waves up to Planck frequency can combine to create an energy source of colossal amount similar to the singularity of Hot Big Bang theory.
The Random Bit Complexity of Mobile Robots Scattering
Authors: Bramas Quentin , Tixeuil Sébastien
Published: April 2017

We consider the problem of scattering n robots in a two dimensional continuous space. As this problem is impossible to solve in a deterministic manner, all solutions must be probabilistic. We investigate the amount of randomness (that is, the number of random bits used by the robots) that is required to achieve scattering.

We first prove that n log n random bits are necessary to scatter n robots in any setting. Also, we give a sufficient condition for a scattering algorithm to be random bit optimal. As it turns out that previous solutions for scattering satisfy our condition, they are hence proved random bit optimal for the scattering problem.

Then, we investigate the time complexity of scattering when strong multiplicity detection is not available. We prove that such algorithms cannot converge in constant time in the general case and in o(log log n) rounds for random bits optimal scattering algorithms. However, we present a family of scattering algorithms that converge as fast as needed without using multiplicity detection. Also, we put forward a specific protocol of this family that is random bit optimal (O(n log n) random bits are used) and time optimal (O(log log n) rounds are used). This improves the time complexity of previous results in the same setting by a log n factor.

Aside from characterizing the random bit complexity of mobile robot scattering, our study also closes the time complexity gap with and without strong multiplicity detection (that is, O(1) time complexity is only achievable when strong multiplicity detection is available, and it is possible to approach a constant value as desired otherwise).
Some Enumeration Results on Binary 2n-Periodic Sequences
Authors: Chang Zuling , Ke Pinhui , Zhao Yongcheng
Published: April 2017

This paper studies some enumeration problems of binary sequences with period 2n based on the Games-Chan algorithm and a modified Stamp-Martin algorithm. We provide the exact number of critical error sequences of binary 2n-periodic sequences corresponding to the second critical point. The exact formula for the number of binary 2n-periodic sequences with exactly three critical points is also derived.
Forecasting Oil Price Trends with Sentiment of Online News Articles
Authors: Li Jian , Xu Zhenjing , Xu Huijuan , Tang Ling , Yu Lean
Published: April 2017

With the rapid development of the Internet and big data technologies, a rich of online data (including news releases) can helpfully facilitate forecasting oil price trends. Accordingly, this study introduces sentiment analysis, a useful big data analysis tool, to understand the relevant information of online news articles and formulate an oil price trend prediction method with sentiment. Three main steps are included in the proposed method, i.e., sentiment analysis, relationship investigation and trend prediction. In sentiment analysis, the sentiment (or tone) is extracted based on a dictionary-based approach to capture the relevant online information concerning oil markets and the driving factors. In relationship investigation, the Granger causality analysis is conducted to explore whether and how the sentiment impacts oil price. In trend prediction, the sentiment is used as an important independent variable, and some popular forecasting models, e.g., logistic regression, support vector machine, decision tree and back propagation neural network, are performed. With crude oil futures prices of the West Texas Intermediate (WTI) and news articles of the Thomson Reuters as studying samples, the empirical results statistically support the powerful predictive power of sentiment for oil price trends and hence the effectiveness of the proposed method.
Monte Carlo simulation on the diffusion of polymer in narrow periodical channels
Authors: Chen Ying-Cai , Zhou Yan-Li , Wang Chao
Published: April 2017

Diffusion of polymer in narrow periodical channels, patterned alternately into part [Formula: see text] and part [Formula: see text] with the same length [Formula: see text], was studied by using Monte Carlo simulation. The interaction between polymer and channel [Formula: see text] is purely repulsive, while that between polymer and channel [Formula: see text] is attractive. Results show that the diffusion of polymer is remarkably affected by the periodicity of channel, and the diffusion constant [Formula: see text] changes periodically with the polymer length [Formula: see text]. At the peaks of [Formula: see text], the projected length of polymer along the channel is an even multiple of [Formula: see text], and the diffusion of polymer in periodical channel is nearly the same as that of polymer in homogeneous channel. While at the valleys of [Formula: see text], the projected length of polymer is an odd multiple of [Formula: see text], and polymer is in a trapped state for a long time and it rapidly jumps to other trapped regions during the diffusion process. The physical mechanisms are discussed from the view of polymer–channel interaction energy landscape.
New mathematics for the nonadditive Tsallis’ scenario
Authors: Ferri G. L. , Pennini F. , plastino A. , Rocca M. C.
Published: April 2017

In this paper, we investigate quantum uncertainties in a Tsallis’ nonadditive scenario. To such an end we appeal to [Formula: see text]-exponentials (qEs), that are the cornerstone of Tsallis’ theory. In this respect, it is found that some new mathematics is needed and we are led to construct a set of novel special states that are the qE equivalents of the ordinary coherent states (CS) of the harmonic oscillator (HO). We then characterize these new Tsallis’ special states by obtaining the associated (i) probability distributions (PDs) for a state of momentum [Formula: see text], (ii) mean values for some functions of space an momenta and (iii) concomitant quantum uncertainties. The latter are then compared to the usual ones.
CEPRAM: Compression for Endurance in PCM RAM
Authors: Gonzalez-Alberquilla Rodrigo , Castro Fernando , Pinuel Luis , Tirado Francisco
Published: April 2017

We deal with the endurance problem of Phase Change Memories (PCM) by proposing Compression for Endurance in PCM RAM [Formula: see text]CEPRAM[Formula: see text], a technique to elongate the lifespan of PCM-based main memory through compression. We introduce a total of three compression schemes based on already existent schemes, but targeting compression for PCM-based systems. We do a two-level evaluation. First, we quantify the performance of the compression, in terms of compressed size, bit-flips and how they are affected by errors. Next, we simulate these parameters in a statistical simulator to study how they affect the endurance of the system. Our simulation results reveal that our technique, which is built on top of Error Correcting Pointers (ECP) but using a high-performance cache-oriented compression algorithm modified to better suit our purpose, manages to further extend the lifetime of the memory system. In particular, it guarantees that at least half of the physical pages are in usable condition for 25% longer than ECP, which is slightly more than 5% more than a scheme that can correct 16 failures per block.
Is Correlation Ranking Really Reliable for the Performance Counter Selection Conducted for Power Estimation?
Authors: Li Yuelong , Wu Jigang , Chen Yawen , Xiao Zhitao , Geng Lei , Zhang Fang , Wu Jun
Published: April 2017

Power estimation is of great value to power-aware adaptation and power provisioning in computing platforms. Performance counter measurements are widely used as main input of the power estimation. However, the number of hardware counters that can be simultaneously measured is relatively small, and the number of OS-level counters is usually far from endurable. As a result, how to pick up the most significant counters becomes an important pre-step of performance counters based power consumption modeling. As the most important criteria of counter selection, correlation between counter measurement and power dissipation has been widely used for several decades, and thus correlation ranking becomes a typical technique for counter selection. However, few works discuss its accuracy and the question why it should be the general first priority. This paper investigates the weightiness of the correlation ranking in counter selection for power estimation. Through comparing correlation ranking with several popular feature selection approaches on tremendous workloads on single and multiple core platforms, we obtain that correlation ranking is not optimal on a large number of benchmarks. Therefore, it can be concluded that correlation ranking should not be generally considered as the first priority to select performance counters. This paper provides an indication for potential researchers to be aware of these issues when estimating power dissipation.
A possible quantum fluid-dynamical approach to vortex motion in nuclei
Authors: Nishiyama Seiya , da Providência João
Published: April 2017

The essential point of Bohr–Mottelson theory is to assume an irrotational flow. As was already suggested by Marumori and Watanabe, the internal rotational motion, i.e., the vortex motion, however, may exist also in nuclei. So, we must take the vortex motion into consideration. In classical fluid dynamics, there are various ways to treat the internal rotational velocity. The Clebsch representation, [Formula: see text] is very powerful and allows for the derivation of the equations of fluid motion from a Lagrangian. Making the best use of this advantage, Kronig–Thellung, Ziman and Ito obtained a Hamiltonian including the internal rotational motion, the vortex motion, through the term [Formula: see text]. Going to quantum fluid dynamics, Ziman and Thellung finally derived the roton spectrum of liquid Helium II postulated by Landau. Is it possible to follow a similar procedure in the description of the collective vortex motion in nuclei? The description of such a collective motion has not been considered in the context of the Bohr–Mottelson model (BMM) for a long time. In this paper, we will investigate the possibility of describing the vortex motion in nuclei on the basis of the theories of Ziman and Ito together with Marumori’s work.
TWO-SCALE DISTRIBUTION OF PRIME NUMBER AND ITS DIFFUSION EQUATION MODEL
Authors: LIANG YINGJIE , CHEN WEN
Published: April 2017

This study reveals the two-scale characteristics in prime number distribution. It is observed a sub-diffusion process of power law decay at the small scale of the natural number [Formula: see text], but is found to obey the classical Brownian motion of an exponential decay at the large scale [Formula: see text]. Such two-scale mechanism gives rise to the multi-fractal scaling from the power law to the exponential law distributions in a transition region of the natural number [Formula: see text]. In the small range, the sub-diffusion of prime number distribution is well depicted by the fractional derivative equation model, and in the large scale, exponential decay distribution can accurately be described by a classical diffusion equation model. The Riemann diffusion equation proposed recently by the present authors can accurately model the prime distribution from small to moderate to large scales and is reduced to the fractional derivative sub-diffusion equation at small scale and the classical Brownian motion diffusion equation at large scale, respectively.
Optimal Dynamic Placement of Virtual Machines in Geographically Distributed Cloud Data Centers
Authors: Teyeb Hana , Hadj-Alouane Nejib Ben , Tata Samir , Balma Ali
Published: April 2017

In geo-distributed cloud systems, a key challenge faced by cloud providers is to optimally tune and configure the underlying cloud infrastructure. An important problem in this context, deals with finding an optimal virtual machine (VM) placement, minimizing costs, while at the same time, ensuring good system performance. Moreover, due to the fluctuations of demand and traffic patterns, it is crucial to dynamically adjust the VM placement scheme over time. It should be noted that most of the existing studies, however, dealt with this problem either by ignoring its dynamic aspect or by proposing solutions that are not suitable for a geographically distributed cloud infrastructure. In this paper, exact as well as heuristic solutions based on Integer Linear programming (ILP) formulations are proposed. Our work focuses also on the problem of scheduling the VM migration by finding the best migration sequence of intercommunicating VMs that minimizes the resulting traffic on the backbone network. The proposed algorithms execute within a reasonable time frame to readjust VM placement scheme according to the perceived demand. Our aim is to use VM migration as a tool for dynamically adjusting the VM placement scheme while minimizing the network traffic generated by VM communication and migration. Finally, we demonstrate the effectiveness of our proposed algorithms by performing extensive experiments and simulation.