bluuebunny/crossref_metadata_2025 huggingface dataset:
Twisted electrostatic waves in a self‐gravitating dusty plasma
Authors: Bukhari S. , Ali S. , Rafique M. , Mendonca J. T.
Published: December 2017

A generalized response (dielectric) function for twisted electrostatic waves is derived for an un‐magnetized self‐gravitating thermal dusty plasma, whose constituents are the Boltzmann‐distributed electrons and positive ions in the presence of negatively charged micrometre‐sized massive dust particulates. For this purpose, a set of Vlasov–Poisson coupled equations is solved along with the perturbed Laguerre–Gauss distribution function, as well as the electrostatic and gravitational potentials in the limit of paraxial approximation. For plane wave solution, the wavefronts of the dust‐acoustic (DA) wave are assumed to have a constant phase with electric and gravitational field lines propagating straight along the propagation axis. On the other hand, non‐planar wave solutions show helical (twisted) wavefronts, in which field lines spiral around the propagation axis owing to the azimuthal velocity component to account for the finite orbital angular momentum (OAM) states. The dispersion relation and damping rate for twisted DA waves are studied both analytically and numerically. It is shown that finite OAM states, the dust to electron temperature ratio, and dust self‐gravitation effects significantly affect the linear dispersion and Landau damping frequencies. In particular, the phase speed of twisted DA waves is reduced with the variation of the twist parameter η (= k/lqϕ), dust concentration δ (= nd0/ni0), and dust self‐gravitation α (= ωJd/ωpd). The relevance of our findings to interstellar dust clouds is also discussed for micrometre‐sized massive dust grains.
Design, modeling, and analysis of online combinatorial double auction for mobile cloud computing markets
Authors: Zhang Yuchao , Xu Ke , Shi Xuelin , Wang Haiyang , Liu Jiangchuan , Wang Yong
Published: December 2017

With the burgeoning of cloud service companies, cloud computing is becoming an efficient means of providing computing resources. Amazon EC2, Rackspace, Google App, and Microsoft Azure are attracting more and more users over the Internet these years. However, in mobile cloud computing (MCC), traditional cloud pricing models can no longer support the above popular applications, because user behaviors are dynamic and time sensitive. As an MCC application is the combination of communication services (eg, wireless access services) and computation services (eg, cloud services), it lacks new auctions for capturing the feature of MCC markets based on the communication and computation cooperation (3C).

In this paper, we design an efficient double‐sided combinatorial auction model in the context of 3C‐based MCC to mitigate this problem. We first propose the framework of online combinatorial double auctions to model mobile cloud computing market. On this base, we give four principles of design requirements, which can make the scheme more efficient and practical, and then we design a new winner determination algorithm that shows how the auction mechanism decides commodity allocation and transaction prices. At last, we conduct a series of experiments to deep analyze the property of our mechanism. The experiment results indicate that the proposed online auction mechanism obtains comparable allocation efficiency to the social optimal solution.
Physiological stress responses to natural variation in predation risk: evidence from white sharks and seals
Authors: Hammerschlag Neil , Meÿer Michael , Seakamela Simon Mduduzi , Kirkman Steve , Fallows Chris , Creel Scott
Published: December 2017

Predators can impact ecosystems through consumptive or risk effects on prey. Physiologically, risk effects can be mediated by energetic mechanisms or stress responses. The predation‐stress hypothesis predicts that risk induces stress in prey, which can affect survival and reproduction. However, empirical support for this hypothesis is both mixed and limited, and the conditions that cause predation risk to induce stress responses in some cases, but not others, remain unclear. Unusually clear‐cut variation in exposure of Cape fur seals (Arctocephalus pusillus pusillus) to predation risk from white sharks (Carcharodon carcharias) in the waters of Southwestern Africa provides an opportunity to test the predation‐stress hypothesis in the wild. Here, we measured fecal glucocorticoid concentrations (fGCM) from Cape fur seals at six discrete islands colonies exposed to spatiotemporal variation in predation risk from white sharks over a period of three years. We found highly elevated fGCM concentrations in seals at colonies exposed to high levels of unpredictable and relatively uncontrollable risk of shark attack, but not at colonies where seals were either not exposed to shark predation or could proactively mitigate their risk through antipredatory behavior. Differences in measured fGCM levels were consistent with patterns of risk at the site and seasonal level, for both seal adults and juveniles. Seal fGCM levels were not correlated with colony population size, density, and geographic location. Investigation at a high risk site (False Bay) also revealed strong correlations between fGCM levels and temporal variation in shark attack rates, but not with shark relative abundance. Our results suggest that predation risk will induce a stress response when risk cannot be predicted and/or proactively mitigated by behavioral responses.
A role for methanogens and methane in the regulation of GLP‐1
Authors: Laverdure Rose , Mezouari Ania , Carson Michael A. , Basiliko Nathan , Gagnon Jeffrey
Published: December 2017

Introduction

The gastrointestinal (GI) microbiome has emerged as a potential regulator of metabolism. However, the precise mechanisms of how microorganisms may influence physiology remain largely unknown. Interestingly, GI microorganisms, including methanogens, are localized within the same regions as the glucagon‐like peptide‐1 (GLP‐1) secreting L cells. GLP‐1 plays key roles appetite and glucose regulation. Furthermore, both methane and GLP‐1 levels are altered in obese humans with metabolic disease. We predict that high‐fat diet‐induced obesity alters the abundance of GI methanogens and that methane may play a role in the GLP‐1 secretory response from the L cell.

Methods

To demonstrate this, GLP‐1 secretion response and faecal methanogens were examined in mice given a high‐fat diet for 14 weeks. In addition, the direct effect of methane on GLP‐1 secretion was assessed in two L‐cell models (NCI‐H716 and GLUTag).

Results

High‐fat diet caused a significant increase in both GLP‐1 secretion and faecal methanogen content. There was a direct correlation between GLP‐1 secretion response and faecal methanogen levels. In L cells, methane stimulated GLP‐1 secretion and enhanced intracellular cAMP content.

Conclusion

These results indicate that alterations in the methanogen communities occurring in obesity may play a vital role in directly enhancing GLP‐1 secretion, and that methane can directly stimulate the secretion of GLP‐1.
Linking knowledge to action: the role of boundary spanners in translating ecology
Authors: Safford Hugh D , Sawyer Sarah C , Kocher Susan D , Hiers J Kevin , Cross Molly
Published: December 2017

One of the most effective ways to foster the co‐production of ecological knowledge by producers and users, as well as encouraging dialogue between them, is to cultivate individuals or organizations working at and managing the boundary between the two groups. Such “boundary spanners” are critical to ensuring scientific salience, credibility, and legitimacy, yet they remain relatively underused in ecology. We summarize some of the major roles of boundary spanners in translational ecology, and suggest that effectiveness in translating ecological information depends on several key factors. These include organizational and individual commitment to boundary spanning over the long term; development of useful, co‐produced products and tools that can subsequently assume boundary‐spanning roles of their own; dual‐accountability frameworks that involve both science providers and users; and identification, training, and retention of science translators who possess a suite of professional skills and individual traits that are rare in scientific circles.
Developing a translational ecology workforce
Authors: Schwartz Mark W , Hiers J Kevin , Davis Frank W , Garfin Gregg M , Jackson Stephen T , Terando Adam J , Woodhouse Connie A , Morelli Toni Lyn , Williamson Matthew A , Brunson Mark W
Published: December 2017

We define a translational ecologist as a professional ecologist with diverse disciplinary expertise and skill sets, as well as a suitable personal disposition, who engages across social, professional, and disciplinary boundaries to partner with decision makers to achieve practical environmental solutions. Becoming a translational ecologist requires specific attention to obtaining critical non‐scientific disciplinary breadth and skills that are not typically gained through graduate‐level education. Here, we outline a need for individuals with broad training in interdisciplinary skills, use our personal experiences as a basis for assessing the types of interdisciplinary skills that would benefit potential translational ecologists, and present steps that interested ecologists may take toward becoming translational. Skills relevant to translational ecologists may be garnered through personal experiences, informal training, short courses, fellowships, and graduate programs, among others. We argue that a translational ecology workforce is needed to bridge the gap between science and natural resource decisions. Furthermore, we argue that this task is a cooperative responsibility of individuals interested in pursuing these careers, educational institutions interested in training scientists for professional roles outside of academia, and employers seeking to hire skilled workers who can foster stakeholder‐engaged decision making.
The Grautschenhof contract – Construction of an intermediate access under complex local conditions
Authors: Klais Frank , Wolf Petra , Lienhart Werner
Published: December 2017

With the start of construction on the third tunnelling contract, work has now started on all sections of the Semmering Base Tunnel. The Tunnel Grautschenhof contract is a challenging construction project with numerous unusual problems. Complex ground conditions make extensive grouting necessary. Numerous constraints above‐ground, like high‐pressure gas pipelines require monitoring and protection measures. Since the start in May 2016, two shafts, the first of three caverns and the first metres of the running tunnels have already been driven. In parallel to this, the works above ground to create two site facilities areas are now largely complete.
Institutional decision to adopt Y90 as primary treatment for hepatocellular carcinoma informed by a 1,000‐patient 15‐year experience
Authors: Salem Riad , Gabr Ahmed , Riaz Ahsun , Mora Ronald , Ali Rehan , Abecassis Michael , Hickey Ryan , Kulik Laura , Ganger Daniel , Flamm Steven , Atassi Rohi , Atassi Bassel , Sato Kent , Benson Al B. , Mulcahy Mary F. , Abouchaleh Nadine , Asadi Ali Al , Desai Kush , Thornburg Bartley , Vouche Michael , Habib Ali , Caicedo Juan , Miller Frank H. , Yaghmai Vahid , Kallini Joseph R. , Mouli Samdeep , Lewandowski Robert J.
Published: December 2017

Yttrium‐90 transarterial radioembolization (TARE) is a locoregional therapy (LRT) for hepatocellular carcinoma (HCC). In this study, we present overall survival (OS) outcomes in a 1,000‐patient cohort acquired over a 15‐year period. Between December 1, 2003 and March 31, 2017, 1,000 patients with HCC were treated with TARE as part of a prospective cohort study. A comprehensive review of toxicity and survival outcomes was performed. Outcomes were stratified by baseline Child‐Pugh (CP) class, United Network for Organ Sharing (UNOS), and Barcelona Clinic Liver Cancer (BCLC) staging systems. Albumin and bilirubin laboratory toxicities were compared to baseline. OS outcomes were reported using censoring and intention‐to‐treat methodologies. All treatments were outpatient, with a median one treatment per patient. Five hundred six (51%) were CP A, 450 (45%) CP B, and 44 (4%) CP C. Two hundred sixty‐three (26%) patients were BCLC A, 152 (15%) B, 541 (54%) C, and 44 (4%) D. Three hundred sixty‐eight (37%) were UNOS T1/T2, 169 (17%) T3, 147 (15%) T4a, 223 (22%) T4b, and 93 (9%) N/M. In CP A patients, censored OS for BCLC A was 47.3 (confidence interval [CI], 39.5‐80.3) months, BCLC B 25.0 (CI, 17.3‐30.5) months, and BCLC C 15.0 (CI, 13.8‐17.7) months. In CP B patients, censored OS for BCLC A was 27 (CI, 21‐30.2) months, BCLC B 15.0 (CI, 12.3‐19.0) months, and BCLC C 8.0 (CI, 6.8‐9.5) months. Forty‐nine (5%) and 110 (11%) patients developed grade 3/4 albumin and bilirubin toxicities, respectively. Conclusion: Based on our experience with 1,000 patients over 15 years, we have made a decision to adopt TARE as the first‐line transarterial LRT for patients with HCC. Our decision was informed by prospective data and incrementally reported demonstrating outcomes stratified by BCLC, applied as either neoadjuvant or definitive treatment. (Hepatology 2017).
Impact of hepatitis C virus polymorphisms on direct‐acting antiviral treatment efficacy: Regulatory analyses and perspectives
Authors: Harrington Patrick R. , Komatsu Takashi E. , Deming Damon J. , Donaldson Eric F. , O'Rear Julian J. , Naeger Lisa K.
Published: December 2017

Several highly effective, interferon‐free, direct‐acting antiviral (DAA)‐based regimens are available for the treatment of chronic hepatitis C virus (HCV) infection. Despite impressive efficacy overall, a small proportion of patients in registrational trials experienced treatment failure, which in some cases was associated with the detection of HCV resistance‐associated substitutions (RASs) at baseline. In this article, we describe methods and key findings from independent regulatory analyses investigating the impact of baseline nonstructural (NS) 3 Q80K and NS5A RASs on the efficacy of current United States Food and Drug Administration (FDA)‐approved regimens for patients with HCV genotype (GT) 1 or GT3 infection. These analyses focused on clinical trials that included patients who were previously naïve to the DAA class(es) in their investigational regimen and characterized the impact of baseline RASs that were enriched in the viral population as natural or transmitted polymorphisms (i.e., not drug‐selected RASs). We used a consistent approach to optimize comparability of results across different DAA regimens and patient populations, including the use of a 15% sensitivity cutoff for next‐generation sequencing results and standardized lists of NS5A RASs. These analyses confirmed that detection of NS3 Q80K or NS5A baseline RASs was associated with reduced treatment efficacy for multiple DAA regimens, but their impact was often minimized with the use of an intensified treatment regimen, such as a longer treatment duration and/or addition of ribavirin. We discuss the drug resistance‐related considerations that contributed to pretreatment resistance testing and treatment recommendations in drug labeling for FDA‐approved DAA regimens. Conclusion: Independent regulatory analyses confirmed that baseline HCV RASs can reduce the efficacy of certain DAA‐based regimens in selected patient groups. However, highly effective treatment options are available for patients with or without baseline RASs. (Hepatology 2018;67:2430‐2448).
Community‐driven demand creation for the use of routine viral load testing: a model to scale up routine viral load testing
Authors: Killingo Bactrin M , Taro Trisa B , Mosime Wame N
Published: December 2017

Introduction

HIV treatment outcomes are dependent on the use of viral load measurement. Despite global and national guidelines recommending the use of routine viral load testing, these policies alone have not translated into widespread implementation or sufficiently increased access for people living with HIV (PLHIV). Civil society and communities of PLHIV recognize the need to close this gap and to enable the scale up of routine viral load testing.

Methods

The International Treatment Preparedness Coalition (ITPC) developed an approach to community‐led demand creation for the use of routine viral load testing. Using this Community Demand Creation Model, implementers follow a step‐wise process to capacitate and empower communities to address their most pressing needs. This includes utlizing a specific toolkit that includes conducting a baseline assessment, developing a treatment education toolkit, organizing mobilization workshops for knowledge building, provision of small grants to support advocacy work and conducting benchmark evaluations.

Results and Discussion

The Community Demand Creation Model to increase demand for routine viral load testing services by PLHIV has been delivered in diverse contexts including in the sub‐Saharan African, Asian, Latin American and the Caribbean regions. Between December 2015 and December 2016, ITPC trained more than 240 PLHIV activists, and disbursed US$90,000 to network partners in support of their national advocacy work. The latter efforts informed a regional, community‐driven campaign calling for domestic investment in the expeditious implementation of national viral load testing guidelines.

Conclusions

HIV treatment education and community mobilization are critical components of demand creation for access to optimal HIV treatment, especially for the use of routine viral load testing. ITPC's Community Demand Creation Model offers a novel approach to achieving this goal.
Assays for estimating HIV incidence: updated global market assessment and estimated economic value
Authors: Morrison Charles S , Homan Rick , Mack Natasha , Seepolmuang Pairin , Averill Megan , Taylor Jamilah , Osborn Jennifer , Dailey Peter , Parkin Neil , Ongarello Stefano , Mastro Timothy D
Published: December 2017

Introduction

Accurate incidence estimates are needed to characterize the HIV epidemic and guide prevention efforts. HIV Incidence assays are cost‐effective laboratory assays that provide incidence estimates from cross‐sectional surveys. We conducted a global market assessment of HIV incidence assays under three market scenarios and estimated the economic value of improved incidence assays.

Methods

We interviewed 27 stakeholders, and reviewed journal articles, working group proceedings, and manufacturers’ sales figures. We determined HIV incidence assay use in 2014, and estimated use in 2015 to 2017 and in 5 to 10‐years under three market scenarios, as well as the cost of conducting national and key population surveys using an HIV incidence assay with improved performance.

Results

Global 2014 HIV incidence assay use was 308,900 tests, highest in Asia and mostly for case‐ and population‐based surveillance. Estimated 2015 to 2017 use was 94,475 annually, with declines due to China and the United States discontinuing incidence assay use for domestic surveillance. Annual projected 5 to 10 year use under scenario 1 – no change in technology – was 94,475. For scenario 2 – a moderately improved incidence assay – projected annual use was 286,031. Projected annual use for scenario 3 – game‐changing technologies with an HIV incidence assay part of (a) standard confirmatory testing, and (b) standard rapid testing, were 500,000 and 180 million, respectively. As HIV incidence assay precision increases, decreased sample sizes required for incidence estimation resulted in $5 to 23 million annual reductions in survey costs and easily offset the approximately $3 million required to develop a new assay.

Conclusions

Improved HIV incidence assays could substantially reduce HIV incidence estimation costs. Continued development of HIV incidence assays with improved performance is required to realize these cost benefits.
Factors associated with HIV testing among young men who have sex with men in Myanmar: a cross‐sectional study
Authors: Pham Minh D , Aung Poe Poe , Paing Aye Kyawt , Pasricha Naanki , Agius Paul A , Tun Waimar , Bajracharya Ashish , Luchters Stanley
Published: December 2017

Introduction

In Myanmar, men who have sex with men (MSM) experience high risk of HIV infection. However, access to HIV testing and prevention services remains a challenge among this marginalized population. The objective of this study was to estimate population prevalence and correlates of prior HIV testing among young MSM (YMSM) and informs the development of HIV testing and intervention programmes that respond to the specific needs of this population.

Methods

Five hundred and eighty‐five YMSM aged 18 to 24 years were recruited using respondent‐driven sampling (RDS) in a cross‐sectional survey conducted in six townships of Myanmar. RDS‐adjusted population estimates were calculated to estimate prevalence of HIV testing; RDS‐weighted logistic regression was used to examine correlates of HIV testing in the past 6 months and in a lifetime.

Results

There were 12 participants who reported receiving a HIV‐positive test; of those, five were tested in the past 6 months. The RDS‐weighted prevalence estimates of lifetime (any prior) HIV testing was 60.6% (95% CI: 53.3% to 66.4%) and of recent (≤ 6 months) HIV testing was 50.1% (95% CI: 44.1% to 55.5%). In multivariable analysis, sexual identity was associated with lifetime but not recent HIV testing. Lifetime and recent HIV testing were associated with having three or more male sexual partners in the past 12 months (adjusted ORs (aORs) = 2.28, 95% CIs: 1.21 to 4.32 and 2.69, 95% CI: 1.59 to 4.56), having good HIV‐related knowledge (aORs = 1.96, 95% CIs: 1.11 to 3.44 and 1.77, 95% CI: 1.08 to 2.89), reporting high HIV testing self‐efficacy (aORs = 13.5, 95% CIs: 6.0 to 30.1 and 9.81, 95% CI: 4.27 to 22.6) and having access to and use of non‐HIV health‐related services in the past 12 months (aORs = 13.2, 95% CIs: 6.85 to 25.6 and 7.15, 95% CI: 4.08 to 12.5) respectively.

Conclusions

HIV testing coverage among YMSM aged 18 to 24 years old in Myanmar is still suboptimal. Integrated HIV testing and prevention services in existing health service provision systems with tailored HIV information and education programmes targeting YMSM to improve HIV‐related knowledge and self‐efficacy may help to promote regular HIV testing behaviour and contribute to sustainable control of the HIV epidemic among this marginalized population in Myanmar.
Greater retention in care among adolescents on antiretroviral treatment accessing “Teen Club” an adolescent‐centred differentiated care model compared with standard of care: a nested case–control study at a tertiary referral hospital in Malawi
Authors: MacKenzie Rachel K , van Lettow Monique , Gondwe Chrissie , Nyirongo James , Singano Victor , Banda Victor , Thaulo Edith , Beyene Teferi , Agarwal Mansi , McKenney Allyson , Hrapcak Susan , Garone Daniela , Sodhi Sumeet K , Chan Adrienne K
Published: December 2017

Introduction

There are numerous barriers to the care and support of adolescents living with HIV (ALHIV) that makes this population particularly vulnerable to attrition from care, poor adherence and virological failure. In 2010, a Teen Club was established in Zomba Central Hospital (ZCH), Malawi, a tertiary referral HIV clinic. Teen Club provides ALHIV on antiretroviral treatment (ART) with dedicated clinic time, sexual and reproductive health education, peer mentorship, ART refill and support for positive living and treatment adherence. The purpose of this study was to evaluate whether attending Teen Club improves retention in ART care.

Methods

We conducted a nested case–control study with stratified selection, using programmatic data from 2004 to 2015. Cases (ALHIV not retained in care) and controls (ALHIV retained in care) were matched by ART initiation age group. Patient records were reviewed retrospectively and subjects were followed starting in March 2010, the month in which Teen Club was opened. Follow‐up ended at the time patients were no longer considered retained in care or on 31 December 2015. Cases and controls were drawn from a study population of 617 ALHIV. Of those, 302 (48.9%) participated in at least two Teen Club sessions. From the study population, 135 (non‐retained) cases and 405 (retained) controls were selected.

Results

In multivariable analyses, Teen Club exposure, age at the time of selection and year of ART initiation were independently associated with attrition. ALHIV with no Teen Club exposure were less likely to be retained than those with Teen Club exposure (adjusted odds ratio (aOR) 0.27; 95% CI 0.16, 0.45) when adjusted for sex, ART initiation age, current age, reason for ART initiation and year of ART initiation. ALHIV in the age group 15 to 19 were more likely to have attrition from care than ALHIV in the age group 10 to 14 years of age (aOR 2.14; 95% CI 1.12, 4.11).

Conclusions

This study contributes to the limited evidence evaluating the effectiveness of service delivery interventions to support ALHIV within healthcare settings. Prospective evaluation of the Teen Club package with higher methodological quality is required for programmes and governments in low‐ and middle‐income settings to prioritize interventions for ALHIV and determine their cost‐effectiveness.
Can statistical downscaling improve consensus among CMIP5 models for Indian summer monsoon rainfall projections?
Authors: Madhusoodhanan C. G. , Shashikanth K. , Eldho T. I. , Ghosh Subimal
Published: December 2017

The projections of plausible changes in future climate using coarse scale General Circulation Models (GCMs) for non‐smooth climate variables, such as precipitation, possess limited skill and are often conflicting. The confidence in precipitation projections is further obscured due to the exclusion of inter‐model and natural internal variability. The present study investigates how far statistical downscaling can provide confidence in future projections while incorporating these major uncertainties under a moderate radiative forcing scenario. Here, we assess the consensus for future changes in Indian Summer Monsoon Rainfall (ISMR) from 20 CMIP5 GCMs and their statistically downscaled counterparts at 0.05° resolution for the 21st century. The Statistical Downscaling (SD) model is skillful in capturing the spatial variability of observed ISMR and shows significant improvement over host GCMs. GCMs show consistent but spatially inhomogeneous increase in future ISMR which intensify towards the end of the century. On the other hand, the downscaled outputs show spatially non‐uniform trends which intensify in their respective directions from near to long term. Both projections show high inter‐model inconsistencies. The multi‐model consensus among GCMs and SD across these in‐congruent models depicts inconclusive and highly uncertain changes in future. The GCMs show significant change with high model inconsistency uniformly across India across time scales. Even though the downscaled outputs show similar results for majority of the Indian landmass, it is highly heterogeneous across time horizons. There is also an emergence of medium evidence for future changes in ISMR for few regions of the country such as the southern Western Ghats, foothills of the Himalaya and central India. The study brings out that even‐improved simulations from downscaling fail to reliably project ISMR due to high inter‐model uncertainty and internal variability. The significant but inconsistent future changes in ISMR projected for a major portion of the Indian subcontinent, in contrast to earlier studies, pose extreme challenges to climate change impact assessments and adaptation/mitigation planning.
Tone mapping to minimize visual sensation distortion considering brightness and local band‐limited contrast
Authors: Shin Seungjun , Kong Kyeongbo , Lee Junggi , Song Woo‐Jin , Kwon Kyung Joon , Kim Seong Gyun
Published: December 2017

We propose a tone‐mapping algorithm that minimizes the function that represents the visual sensation distortion that occurs after tone mapping. For the function, we consider both brightness and local band‐limited contrast to reduce darkening of images that have high dynamic range when they are displayed with conventional contrast‐based tone mapping using histogram on devices that have low dynamic range. By exploiting human visual characteristics, we simplify the problem and find a closed‐form solution that minimizes the function that represents distortion of visual sensation. In both subjective and objective evaluations, the proposed algorithm achieves a processed image that is most similar to the original image and has the best subjective image quality.
Posttraumatic Stress, Somatization, and Quality of Life Among Ivorian Refugees
Authors: Kounou Kossi B. , Brodard Fabrice , Gnassingbe Afèignindou , Dogbe Foli Ayoko A. , Sager Julia C. , Schmitt Laurent , Bui Eric
Published: December 2017

The present study examined the relationship between peritraumatic reactions, posttraumatic stress disorder (PTSD) symptoms, somatization, and quality of life (QoL) in a sample of refugees, two years after the 2011 Ivory Coast sociopolitical crisis. Participants were 101 Ivorian adult refugees (mean age = 31.61 years, SD = 7.84; 45.5% women) who completed several questionnaires relating to peritraumatic reactions, PTSD symptoms, somatization, and QoL. Most participants (86.1%) scored above the cutoff for probable PTSD. Peritraumatic dissociation and peritraumatic distress were significantly associated with PTSD symptoms, (r = .64, p < .001) and (r = .60, p < .001), respectively, and somatization, (r = .21, p = .038) and (r = .35, p < .001), respectively, as well as with QoL, (r = –.20, p = .045) and (r = –.21, p = .037), respectively. Similarly, QoL was significantly negatively correlated with PTSD symptoms (r = −.33, p < .001) and somatization (r = −.39, p < .001). In multivariate analyses, somatization was the strongest predictor of QoL (β = −.31, p = .003). Finally, somatization statistically mediated the association between peritraumatic distress and QoL. These findings suggest that PTSD may be frequent among Ivorian refugees, and that somatization may be an important feature of the traumatic experiences. Targeting somatization in conjunction with trauma‐centered therapy may improve outcomes in sub‐Saharan Africans with PTSD.
Spatially almost periodic solutions for active scalar equations
Authors: Li Chengrui
Published: December 2017

We are concerned with a family of dissipative active scalar equation on
. By using similar methods from the previous paper of Y. Giga et al. (see Introduction below), we construct a unique real, spatially almost periodic mild solution θ of satisfying . In this paper, we consider some countable sum‐closed frequency sets (see Remark ). We show that the property of the solution is rather different from Chae et al and obtain that
with some initial data θ0 for all t≥0,
and 0≤α≤ω, where ω is a fixed constant. Furthermore, arranging the elements of a countable sum‐closed frequency set Fδ as in Remark , we have for any 0≤α≤ω that
belongs to
, where Fδ is defined in or .
In vivo characterization of brain ultrashort‐T2 components
Authors: Boucneau Tanguy , Cao Peng , Tang Shuyu , Han Misung , Xu Duan , Henry Roland G. , Larson Peder E. Z.
Published: December 2017

Purpose

Recent nuclear magnetic resonance and MRI studies have measured a fast‐relaxing signal component with
ms in white matter and myelin extracts. In ex vivo studies, evidence suggests that a large fraction of this component directly arises from bound protons in the myelin phospholipid membranes. Based on these results, this ultrashort‐T2 component in nervous tissue is a new potential imaging biomarker of myelination, which plays a critical role in neuronal signal conduction across the brain and loss or degradation of myelin is a key feature of many neurological disorders. The goal of this work was to characterize the relaxation times and frequency shifts of ultrashort‐T2 components in the human brain.

Methods

This required development of an ultrashort echo time relaxometry acquisition strategy and fitting procedure for robust measurements in the presence of ultrashort
relaxation times and large frequency shifts.

Results

We measured an ultrashort‐T2 component in healthy volunteers with a median
between 0.5–0.7 ms at 3T and 0.2–0.3 ms at 7T as well as an approximately −3 ppm frequency shift from water.

Conclusion

To our knowledge, this is the first time a chemical shift of the ultrashort‐T2 brain component has been measured in vivo. This chemical shift, at around 1.7 ppm, is similar to the primary resonance of most lipids, indicating that much of the ultrashort‐T2 component observed in vivo arises from bound protons in the myelin phospholipid membranes. Magn Reson Med 80:726–735, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Evaluating the parent–adolescent communication toolkit: Usability and preliminary content effectiveness of an online intervention
Authors: Toombs Elaine , Unruh Anita , McGrath Patrick
Published: December 2017

Aim

This study aimed to assess the Parent–Adolescent Communication Toolkit, an online intervention designed to help improve parent communication with their adolescents. Participant preferences for two module delivery systems (sequential and unrestricted module access) were identified.

Design

Usability assessment of thePACTintervention was completed using pre‐test and posttest comparisons. Usability data, including participant completion and satisfaction ratings were examined.

Methods

Parents (N = 18) of adolescents were randomized to a sequential or unrestricted chapter access group. Parent participants completed pre‐test measures, thePACTintervention and posttest measures. Participants provided feedback for the intervention to improve modules and provided usability ratings. Adolescent pre‐ and posttest ratings were evaluated.

Results

Usability ratings were high and parent feedback was positive. The sequential module access groups rated the intervention content higher and completed more content than the unrestricted chapter access group, indicating support for the sequential access design. Parent mean posttest communication scores were significantly higher (p < .05) than pre‐test scores. No significant differences were detected for adolescent participants. Findings suggest that the Parent–Adolescent Communication Toolkit has potential to improve parent–adolescent communication but further effectiveness assessment is required.
Nurse anaesthetist students' experiences of patient dignity in perioperative practice—a hermeneutic study
Authors: Valeberg Berit T. , Liodden Ingrid , Grimsmo Bergsvein , Lindwall Lillemor
Published: December 2017

Aim

The aim of the study was to describe how nurse anaesthetist students experienced patient dignity in perioperative practice.

Design

A hermeneutical design and the critical incident technique were used to obtain experiences from practice.

Method

In the Autumn of 2015, after participating in a mandatory lecture on ethics, 23 nurse anaesthetist students reported their experiences and interpretation concerning violation and preservation of patients' dignity in the operating theatre. The text, which was a compilation of descriptions of 35 incidents, was analysed by using hermeneutical text interpretation.

Findings

The text revealed three main themes preserving patients' dignity: allocating time to the patient, inviting the patient to participate and shielding the patient's body. Furthermore, three main themes of dignity violation were identified: alienation, backbiting and violation of intimate sphere.

Conclusion

Discussion and reflection based on the personal experience of the students during their practice are ways to strengthen ethical awareness and promote an ethical and dignified caring culture.
Age Variation in the Association Between Obesity and Mortality in Adults
Authors: Wang Zhiqiang , Peng Yang , Liu Meina
Published: December 2017

Objective

The aim of this study was to evaluate the previously reported finding that the association between obesity and mortality strengthens with increasing age.

Methods

The data were derived from the National Health Interview Survey. Age‐specific hazard ratios of mortality for grade 2/3 obesity (BMI ≥ 35 kg/m2), relative to a BMI of 18.5 kg/m2 to < 25 kg/m2, were calculated by using a flexible parametric survival model (240,184 white men) and Cox proportional hazard models (51,697 matched pairs).

Results

When the model included interaction terms between obesity and age at the survey, hazard ratios appeared to increase with age if those interaction terms were ignored by fixing age at the survey as a single value. However, when recalculated for adults with various ages at the survey, according to model specifications, hazard ratios were higher for younger adults than for older adults with the same follow‐up duration. Based on matched data, hazard ratios were also higher for younger adults (2.14 [95% CI: 1.90‐2.40] for those 40‐49 years of age) than for older adults (1.22 [95%: 0.91‐1.63] for those 90+ years of age).

Conclusions

For any given follow‐up duration, the association between obesity and mortality weakens with age. The previously reported strengthening of the obesity‐mortality association with increasing age was caused by the failure to take all the model specifications into consideration when calculating adjusted hazard ratios.
Regulation of secondary cell wall biosynthesis by a NAC transcription factor from Miscanthus
Authors: Golfier Philippe , Volkert Christopher , He Feng , Rausch Thomas , Wolf Sebastian
Published: December 2017

Cell wall recalcitrance is a major limitation for the sustainable exploitation of lignocellulosic biomass as a renewable resource. Species and hybrids of the genus Miscanthus have emerged as candidate crops for the production of lignocellulosic feedstock in temperate climates, and dedicated efforts are underway to improve biomass yield. However, nothing is known about the molecular players involved in Miscanthus cell wall biosynthesis to facilitate breeding efforts towards tailored biomass. Here, we identify a Miscanthus sinensis transcription factor related to SECONDARY WALL‐ASSOCIATED NAC DOMAIN1 (SND1), which acts as a master switch for the regulation of secondary cell wall formation and lignin biosynthesis. MsSND1 is expressed in growth stages associated with secondary cell wall formation, together with its potential targets. Consistent with this observation, MsSND1 was able to complement the secondary cell wall defects of the Arabidopsis snd1 nst1 double mutant, and ectopic expression of MsSND1 in tobacco leaves was sufficient to trigger patterned deposition of cellulose, hemicellulose, and lignin reminiscent of xylem elements. Transgenic studies in Arabidopsis thaliana plants revealed that MsSND1 regulates, directly and indirectly, the expression of a broad range of genes involved in secondary cell wall formation, including MYB transcription factors which regulate only a subset of the SCW differentiation program. Together, our findings suggest that MsSND1 is a transcriptional master regulator orchestrating secondary cell wall biosynthesis in Miscanthus.
Antimicrobial activity of the indolicidin‐derived novel synthetic peptide In‐58
Authors: Vasilchenko A. S. , Vasilchenko A. V. , Pashkova T. M. , Smirnova M. P. , Kolodkin N. I. , Manukhov I. V. , Zavilgelsky G. B. , Sizova E. A. , Kartashova O. L. , Simbirtsev A. S. , Rogozhin E. A. , Duskaev G. K. , Sycheva M. V.
Published: December 2017

Natural peptides with antimicrobial activity are extremely diverse, and peptide synthesis technologies make it possible to significantly improve their properties for specific tasks. Here, we investigate the biological properties of the natural peptide indolicidin and the indolicidin‐derived novel synthetic peptide In‐58. In‐58 was generated by replacing all tryptophan residues on phenylalanine in D‐configuration; the α‐amino group in the main chain also was modified by unsaturated fatty acid. Compared with indolicidin, In‐58 is more bactericidal, more resistant to proteinase K, and less toxic to mammalian cells. Using molecular physics approaches, we characterized the action of In‐58 on bacterial cells at the cellular level. Also, we have found that studied peptides damage bacterial membranes. Using the Escherichia coli luminescent biosensor strain MG1655 (pcolD’::lux), we investigated the action of indolicidin and In‐58 at the subcellular level. At subinhibitory concentrations, indolicidin and In‐58 induced an SOS response. Our data suggest that indolicidin damages the DNA, but bacterial membrane perturbation is its principal mode of action. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.
Surface Nonlinear Gratings by Direct Multiphoton Microscope Writing
Authors: Avalos‐Hernández Jonathan , Carriles Ramon , Domínguez‐Juárez Jorge Luis
Published: December 2017

Thin film fabrication and patterning using organic molecules is of interest for technological and optoelectronic applications, among others. We demonstrate a new method to realize surface periodic patterning using femtosecond laser radiation from a multiphoton microscope. The laser is focused on organic films to generate a homogeneous 2D structure on a flat surface. The organic film was deposited onto microscope slides by immersion. From the gratings, the relative position of the nonlinearly diffracted first order maxima of second harmonic generation was measured. It is shown that nonlinear diffraction orders can be manipulated by the characteristics of the surface periodic patterning. It is possible to extend this writing scheme to arbitrary patterns and possibly curved surfaces with potential applications in couplers and waveguides. This method might also be useful to perform selective linear and nonlinear spectroscopy by modulating the linear and nonlinear activity of dyes deposited on the surface of microresonators or similar devices.
Adaptive LFT control of a civil aircraft with online frequency‐domain parameter estimation
Authors: Ferreres G. , Hardier G.
Published: December 2017

This paper describes the application of an indirect linear fractional transformation (LFT)–based state‐space adaptive control scheme to a transport aircraft, within the context of the European project REconfiguration of CONtrol in Flight for Integral Global Upset REcovery. The principle of the scheme is to design and validate off‐line a gain‐scheduled controller, depending on the plant parameters to be estimated, and to combine it online with a model estimator, so as to minimize the onboard computational time and complexity. A modal approach, very classical for the design of a flight control law, is used to directly synthesize the static output feedback LFT controller, depending on the control and stability derivatives, ie, the parameters of the linearized aerodynamic state‐space model to be estimated. Since the gain‐scheduled LFT controller online depends on the parameter estimates instead of the true values, its robustness to transient and asymptotic estimation errors needs to be assessed using μ and integral quadratic constraint analysis techniques. A primary concern being an online implementation, a fully recursive frequency‐domain estimation technique is proposed, with a low online computational burden and the capability to track time‐varying parameters. Full nonlinear simulations along a trajectory validate the good performance properties of the combined estimator and gain‐scheduled flight controller. To some extent, minimal guaranteed stability and performance properties of the adaptive scheme can be ensured by switching to a robust controller when the parameter estimates are not reliable enough, thus bypassing the Certainty Equivalence Principle.
Ninhydrin‐Based Chemosensor for the Selective Detection and Scavenging of Mercury(II) Ions in Aqueous Solution
Authors: Balamurugan Gopal , Velmathi Sivan
Published: December 2017

Indeno[1, 2‐b]quinoxalinone derivative (N2) was synthesized based on the thiophilic interaction of mercury(II) ions that could possess selectivity and was characterized using HSQC, HRMS and other techniques. From the naked eye sensing experiments with various anions and cations, N2 showed selectivity towards Cu(II) with colour change from colourless to pink whereas Hg(II) with colour change to orange followed by precipitaion of N2‐Hg(II) complex. HRMS, 1H NMR studies and life time measurements support the sensing behavior of N2. The precipitation of N2‐Hg(II) complex was productively developed for the scavenging of mercuric ions in the real samples under 100% aqueous medium by N2 adsorbed over silica (SN2) and cyclic voltammetry was used to validate the application.
A Combined Theoretical and FT‐IR Spectroscopy Study of a Hybrid Poly(furfuryl alcohol) – Lignin Material: Basic Chemistry of a Sustainable Wood Protection Method.
Authors: Barsberg Søren T. , Thygesen Lisbeth G.
Published: December 2017

The sustainable wood protective modification known as “furfurylation” relies on the formation of a polymer of furfuryl alcohol (FA) that interacts with lignin within wood cell walls. In this study we gain new insight on the reaction by combining density functional theory based methods with an FTIR spectroscopic study. For a set of monolignol models we study their condensation reaction with FA and find the reaction enthalpy for their most reactive sites to be near‐identical to FA self‐condensation, and indistinguishable between p‐hydroxyphenyl, guaiacyl and syringyl (H, G and S type) phenolic and non‐phenolic models. For selected models experimental and predicted FTIR spectra confirmed FA condensation to uncrowded ring positions. However, for more realistic β‐O‐4 dimer models we predicted the most reactive sites to be Cα and Cγ in addition to the non‐crowded ring positions. An analysis of expected prediction errors is presented too. We discuss the implications of these findings for the properties of the lignin‐poly(FA) hybrid material within the wood cell wall.
Desulfurization of Thioketals into Methylene and Methyl Derivatives: Nickel or not Nickel?
Authors: Zhao Guangkuan , Yuan Ling‐Zhi , Alami Mouad , Provot Olivier
Published: December 2017

In this review, the desulfurization of thioacetals and thioketals leading to methyl and methylene derivatives is summarized through metal and metal‐free methodologies. In the section concerning the use of metals for desulfurization reactions, we will be successively presenting and discussing all methods requiring Ni and Ni derivatives as reducing agents and other examples in which metals were used to generate solvating electrons as reducing species. The following section will concern the use of other desulfurizing agents as metal‐hydrides (Bu3SnH, Et3SiH) and metal‐free desulfurization reactions of thioketals. The functional group tolerance of the presented methods with functionalized and sensitive substrates will be discussed.
Copper‐Catalyzed Selective Synthesis of 5‐Selanyl‐imidazo[2,1‐b]thiazoles
Authors: Santos Kelvin S. , Sandagorda Eduardo M. A. , Cargnelutti Roberta , Barcellos Thiago , Jacob Raquel G. , Alves Diego , Schumacher Ricardo F.
Published: December 2017

We describe a selective and direct method to synthesize a wide variety of 5‐selanyl‐imidazo[2,1‐b]thiazoles by copper(I)–catalyzed reaction of imidazo[2,1‐b]thiazoles with diorganyl diselenides. The reactions were carried out in DMSO at 90 °C in air. The methodology was tolerant to differently substituted diorganyl diselenides containing electron‐deficient, electron‐rich, and bulky groups. Still, various imidazo[2,1‐b]thiazoles were used and furnishing the expected products in good to excellent yields. All the products were selectively coupled at 5‐position of the imidazo[2,1‐b]thiazole and no regioisomers were detected.