bluuebunny/crossref_metadata_2025 huggingface dataset:
Transient Computational Fluid Dynamics/Discrete Element Method Simulation of Gas–Solid Flow in a Spouted Bed and Its Validation by High-Speed Imaging Experiment
Authors: Zhou Ling , Zhang Lingjie , Shi Weidong , Agarwal Ramesh , Li Wei
Published: August 2017

A coupled computational fluid dynamics (CFD)/discrete element method (DEM) is used to simulate the gas–solid two-phase flow in a laboratory-scale spouted fluidized bed. Transient experimental results in the spouted fluidized bed are obtained in a special test rig using the high-speed imaging technique. The computational domain of the quasi-three-dimensional (3D) spouted fluidized bed is simulated using the commercial CFD flow solver ANSYS-fluent. Hydrodynamic flow field is computed by solving the incompressible continuity and Navier–Stokes equations, while the motion of the solid particles is modeled by the Newtonian equations of motion. Thus, an Eulerian–Lagrangian approach is used to couple the hydrodynamics with the particle dynamics. The bed height, bubble shape, and static pressure are compared between the simulation and the experiment. At the initial stage of fluidization, the simulation results are in a very good agreement with the experimental results; the bed height and the bubble shape are almost identical. However, the bubble diameter and the height of the bed are slightly smaller than in the experimental measurements near the stage of bubble breakup. The simulation results with their experimental validation demonstrate that the CFD/DEM coupled method can be successfully used to simulate the transient gas–solid flow behavior in a fluidized bed which is not possible to simulate accurately using the granular approach of purely Euler simulation. This work should help in gaining deeper insight into the spouted fluidized bed behavior to determine best practices for further modeling and design of the industrial scale fluidized beds.
An analysis of the LIGO discovery based on introductory physics
Authors: Mathur Harsh , Brown Katherine , Lowenstein Ashton
Published: August 2017

By observing gravitational radiation from a binary black hole merger, the LIGO collaboration has simultaneously opened a new window on the universe and achieved the first direct detection of gravitational waves. Here this discovery is analyzed using concepts from introductory physics. Drawing upon Newtonian mechanics, dimensional considerations, and analogies between gravitational and electromagnetic waves, we are able to explain the principal features of LIGO's data and make order of magnitude estimates of key parameters of the event by inspection of the data. Our estimates of the black hole masses, the distance to the event, the initial separation of the pair, and the stupendous total amount of energy radiated are all in good agreement with the best fit values of these parameters obtained by the LIGO-VIRGO collaboration.
An extraordinary tabletop speed of light apparatus
Authors: Pegna Guido
Published: August 2017

A compact, low-cost, pre-aligned apparatus of the modulation type is described. The apparatus allows accurate determination of the speed of light in free propagation with an accuracy on the order of one part in 104. Due to the 433.92 MHz radio frequency (rf) modulation of its laser diode, determination of the speed of light is possible within a sub-meter measuring base and in small volumes (some cm3) of transparent solids or liquids. No oscilloscope is necessary, while the required function generators, power supplies, and optical components are incorporated into the design of the apparatus and its receiver can slide along the optical bench while maintaining alignment with the laser beam. Measurement of the velocity factor of coaxial cables is also easily performed. The apparatus detects the phase difference between the rf modulation of the laser diode by further modulating the rf signal with an audio frequency signal; the phase difference between these signals is then observed as the loudness of the audio signal. In this way, the positions at which the minima of the audio signal are found determine where the rf signals are completely out of phase. This phase detection method yields a much increased sensitivity with respect to the display of coincidence of two signals of questionable arrival time and somewhat distorted shape on an oscilloscope. The displaying technique is also particularly suitable for large audiences as well as in unattended exhibits in museums and science centers. In addition, the apparatus can be set up in less than one minute.
The geometry of relativity
Authors: Dray Tevian
Published: August 2017

Geometric treatments of both special and general relativity are outlined, suitable for students in the sciences who are seeing these topics for the first time. Both the advantages and disadvantages of such an approach, and its relationship to more traditional approaches, are then discussed.
The variational-relaxation algorithm for finding quantum bound states
Authors: Schroeder Daniel V.
Published: August 2017

I describe a simple algorithm for numerically finding the ground state and low-lying excited states of a quantum system. The algorithm is an adaptation of the relaxation method for solving Poisson's equation, and is fundamentally based on the variational principle. It is especially useful for two-dimensional systems with nonseparable potentials, for which simpler techniques are inapplicable yet the computation time is minimal.
Hearing thresholds of a male and a female harbor porpoise (Phocoena phocoena)
Authors: Kastelein Ronald A. , Helder-Hoek Lean , Van de Voorde Shirley
Published: August 2017

To study intra-species variability in audiograms, the hearing sensitivity of a six-year-old female and a three-year-old male harbor porpoise was measured by using a standard psycho-acoustic technique under low ambient noise conditions. The porpoises' hearing thresholds for 13 narrow-band sweeps with center frequencies between 0.125 and 150 kHz were established. The resulting audiograms were U-shaped and similar. The main difference (25 dB) in mean thresholds between the two porpoises was at the high-frequency end of the hearing range (at 150 kHz). Maximum sensitivity (47 dB re 1 μPa for the female and 44 dB re 1 μPa for the male) occurred at 125 kHz. The range of most sensitive hearing (defined as within 10 dB of maximum sensitivity) was from 16 to ∼140 kHz. Sensitivity declined sharply above 125 kHz. All five porpoises for which a valid behavioral audiogram now exists were rehabilitated stranded animals, all were tested with similar psycho-acoustic techniques, and all had similar audiograms. The present study provides further evidence to confirm that the hearing range and sensitivity of the first three harbor porpoises, which have been used in secondary research and on which policy decisions have been based, are representative of those of young harbor porpoises in general.
A differential pressure extensional rheometer on a chip with fully developed elongational flow
Authors: Lee Heon Sang , Muller Susan J.
Published: August 2017

A method is presented to construct a fully developed elongational flow at a nearly constant extension rate in a converging microchannel. For a Giesekus–Leonov fluid, we show that under appropriate conditions, the first normal stress difference in a fluid element flowing along the channel centerline reaches its steady-state value early in the converging region, so that the time-averaged normal stress difference is approximately equal to the spatially averaged normal stress along the converging section. We demonstrate that the averaged normal stress in the converging region (with contraction ratios of 4.9 or 10.343) maintains greater than 90% of the steady value up to an extension rate of 100 s−1. At higher extension rates, the averaged normal stress becomes significantly smaller than the steady value. A differential pressure elongational rheometer is proposed where the pressure difference between the converging channel and a reference channel can be monitored. The reference channel is a straight channel geometry in which the viscous contribution to the pressure drop equals that in the converging channel.
Fertile offspring from sterile sex chromosome trisomic mice
Authors: Hirota Takayuki , Ohta Hiroshi , Powell Benjamin E. , Mahadevaiah Shantha K. , Ojarikre Obah A. , Saitou Mitinori , Turner James M. A.
Published: August 2017

Trisomic animals lose third chromosome

Generally, when a third sex chromosome is added to the normal two in mammals (XX for female and XY for male), developmental defects result. Mice that are trisomic for the sex chromosomes are infertile. Hirota
et al.
demonstrate that reprogramming cells from sterile mice with chromosome trisomies XXY or XYY generates XY stem cells. Sperm generated from these XY stem cells could give rise to healthy, fertile offspring. Reprogramming also promoted loss of the extra chromosome in cells from patients with Klinefelter (XXY) or Down (trisomy 21) syndrome.

Science
, this issue p.
932
Dynamic multinuclear sites formed by mobilized copper ions in NO

x

selective catalytic reduction
Authors: Paolucci Christopher , Khurana Ishant , Parekh Atish A. , Li Sichi , Shih Arthur J. , Li Hui , Di Iorio John R. , Albarracin-Caballero Jonatan D. , Yezerets Aleksey , Miller Jeffrey T. , Delgass W. Nicholas , Ribeiro Fabio H. , Schneider William F. , Gounder Rajamani
Published: August 2017

X-ray vision spies copper on the move

Copper ions in zeolites help remove noxious nitrogen oxides from diesel exhaust by catalyzing their reaction with ammonia and oxygen. Paolucci
et al.
found that these copper ions may move about during the reaction (see the Perspective by Janssens and Vennestrom). Zeolite catalysts generally fix metals in place while the reacting partners flow in and out of their cagelike structures. In this case, though, x-ray absorption spectroscopy suggested that the ammonia was mobilizing the copper ions to pair up as they activated oxygen during the catalytic cycle.

Science
, this issue p.
898
; see also p.
866
Draft Genome Sequences of Two Pseudomonas aeruginosa Bloodstream Infection Isolates Associated with Rapid Patient Death
Authors: McCarthy K. L. , Jennison A. V. , Wailan A. M. , Paterson D. L.
Published: August 2017

The morbidity and mortality associated with
Pseudomonas aeruginosa
bloodstream infections are significant. New strategies are required to treat such infections. We report here the draft genome sequences of two antibiotic-sensitive
P. aeruginosa
bloodstream infection isolates that were associated with rapid death in nonneutropenic patients.
Draft Genome Sequence of Lactobacillus fermentum BFE 6620, a Potential Starter Culture for African Vegetable Foods, Isolated from Fermented Cassava
Authors: Wafula Eliud N. , Brinks Erik , Becker Biserka , Huch Melanie , Trierweiler Bernhard , Mathara Julius M. , Oguntoyinbo Folarin A. , Cho Gyu-Sung , Franz Charles M. A. P.
Published: August 2017

We report the draft genome sequence of
Lactobacillus fermentum
BFE 6620 from fermented cassava used as a potential starter culture for African vegetable fermentation. Sequence analysis showed the assembled genome size to be 1,982,893 bp, encoding a predicted total of 2,003 protein-coding genes, 14 rRNAs, 54 tRNAs, and 3 noncoding RNAs (ncRNAs).
First Genome Sequence of Shallot Latent Carlavirus from
Allium macrostemon
Bunge
Authors: Ohshima Kazusato , Okamura Kouta , Yasaka Ryosuke , Fukuda Shinji , Ishimaru Kanji , Tomitaka Yasuhiro , Yamashita Kazuo
Published: August 2017

A wild Japanese garlic plant (
Allium macrostemon
Bunge, wild onion) with leaves showing chlorotic stripes was collected in Saitama Prefecture, Japan. Genome sequencing showed that it was infected with shallot latent carlavirus. The genomic sequence of this virus is reported for the first time from wild onion.
Draft Genome Sequence of
Grammothele lineata
SDL-CO-2015-1, a Jute Endophyte with a Potential for Paclitaxel Biosynthesis
Authors: Das Avizit , Ahmed Oly , Baten A. K. M. Abdul , Bushra Samira , Islam M. Tariqul , Ferdous Ahlan Sabah , Islam Mohammad Riazul , Khan Haseena
Published: August 2017

Grammothele lineata
strain SDL-CO-2015-1, a basidiomycete fungus, was identified as an endophyte from a jute species,
Corchorus olitorius
var. 2015, and found to produce paclitaxel, a diterpenic polyoxygenated pseudoalkaloid with antitumor activity. Here, we report the draft genome sequence (42.8 Mb with 9,395 genes) of this strain.
Draft Genome Sequence of Klebsiella pneumoniae 704SK6, an OXA-48- and CTX-M-15-Encoding Wastewater Isolate
Authors: Marti Roger , Stephan Roger , Klumpp Jochen , Nüesch-Inderbinen Magdalena , Hummerjohann Jörg , Bagutti Claudia , Zurfluh Katrin
Published: August 2017

The Swiss wastewater isolate
Klebsiella pneumoniae
704SK6, encoding OXA-48 and CTX-M-15 β-lactamases, was fully sequenced. The assembly resulted in an open chromosome of 5,208,104 bp in size (G+C content, 57.6%) and four closed plasmid sequences of 209,651, 197,670, 65,998, and 63,605 bp in size.
Interobserver agreement and image quality of functional cardiac ultrasound measures used in a randomised trial of delayed cord clamping in preterm infants
Authors: Popat Himanshu , Robledo Kristy P , Sebastian Lucille , Evans Nicholas , Gill Andrew , Kluckow Martin , Sinhal Sanjay , Waal Koert de , Tarnow-Mordi William , Osborn David
Published: August 2017

Objective

Functional cardiac ultrasound measures are used clinically and in trials for assessing the haemodynamic status of newborn infants. Superior vena cava (SVC) flow and right ventricular output (RVO) are established measures of systemic blood flow on the first postnatal day. The objective was to assess image quality and interobserver agreement of these measures in preterm infants enrolled in a randomised trial of immediate versus delayed cord clamping.

Design and setting

Image quality and interobserver agreement for SVC flow, RVO and ductus arteriosus (DA) size were assessed on measurements taken at 3–6, 6–12 and 20–28 hours for the first 10 infants enrolled at each of four sites (total 40). Bland-Altman plots were constructed; mean difference (bias) and limits of agreement (LOA) were calculated. Potential sources of variation were explored.

Results

Quality was judged satisfactory for >97% of images. The mean difference and LOA between the observers were 5.4 mL/kg/min and −49.0 to 59.8 mL/kg/min for SVC flow, −26.6 mL/kg/min and −131.4 to 78.2 mL/kg/min for RVO, and 0 mm and −0.8 to 0.8 mm for DA diameter, respectively. The principal source of measurement error for SVC flow was diameter, and for RVO, diameter and velocity time integral. The difference between observers for both SVC and RVO was significantly associated with site.

Conclusion

Interobserver variability for SVC flow is consistent with that previously reported, but higher for RVO. The findings should be incorporated into clinical practice, training, accreditation and trial design.
Inguinal canal spermatic cord leiomyoma presenting as an incarcerated inguinal hernia
Authors: Koprivanac Marijan , Billings Steven D , Khachaturov Vadim , Morris-Stiff Gareth
Published: August 2017

Leiomyoma is a benign neoplasm originating from smooth muscle cells and is most commonly seen in the uterus, followed by the small bowel and oesophagus. We report a rare case of a 41-year-old male patient with a spermatic cord leiomyoma that presented as an inguinal canal mass mimicking an irreducible inguinal hernia without scrotal involvement. This report highlights the rare presentation and workup of an inguinal mass, importance of intraoperative decision making based on operative findings and the significance of postoperative pathology findings.
Prevalence, subtypes, severity and determinants of ocular trauma: The Singapore Chinese Eye Study
Authors: Wong Mark YZ , Man Ryan EK , Gupta Preeti , Sabanayagam Charumathi , Wong Tien Yin , Cheng Ching-Yu , Lamoureux Ecosse Luc
Published: August 2017

Purpose

To describe the prevalence, subtypes, severity and determinants of ocular trauma (OT) in a population-based study in Singapore.

Methods

We included 3353 Chinese adults aged ≥40 years from the Singapore Chinese Eye Study, a population-based study, conducted between 2009 and 2011. OT was defined as self-reported history of any eye injury requiring medical attention with or without hospitalisation, and further classified as blunt object, sharp object or chemical burns related. Age and gender-standardised prevalence was estimated using the 2010 Singapore Chinese population census. Multivariable models were used to assess the independent associations of OT with age, gender, income, education, literacy, alcohol consumption, smoking and history of falls.

Results

The mean (SD) age was 59.7 (9.9) years and 49.4% were male. There were 138 OT cases, giving a crude and age and gender-standardised prevalence of 4.1% (95% CI 3.5% to 4.8%) and 4.4% (95% CI 3.7% to 5.2%), respectively. Of these, 45 (32.6%), 56 (40.6%) and 10 (7.3%) were blunt object, sharp object and chemical burns-related trauma, respectively. Twenty eight (20.3%) required hospitalisation, with no difference between subtypes. In multivariable models, men (OR (95% CI): 2.80 (1.79–4.39)), younger persons (per year decrease in age (1.03 (1.00–1.05)) and lower education levels (1.8 (1.25–2.60); comparing ≤6 years vs >6 years of education) were independent determinants of OT.

Conclusions

OT affected one in 25 adults, with 20% of these requiring hospitalisation. Because OT is preventable, raising awareness and education strategies in the population would allow prevention of vision loss particularly in men, and younger and lesser-educated individuals.
Effect of high-flow nasal therapy during acute aerobic exercise in patients with chronic obstructive pulmonary disease after exacerbation: protocol for a randomised, controlled, cross-over trial
Authors: Prieur Guillaume , Medrinal Clement , Combret Yann , Quesada Aurora Robledo , Prieur Fabrice , Quieffin Jean , Borel Jean Christian , Reychler Gregory
Published: August 2017

Introduction

Early pulmonary rehabilitation is recommended after a severe exacerbation of chronic obstructive pulmonary disease (COPD). However, this is difficult to implement, particularly for exercise training. High-flow nasal therapy (HFNT) may reduce the work of breathing and dyspnoea and may improve exercise tolerance.

Methods and analysis

This is a single-centre, prospective, controlled, randomised, cross-over study. Eligible patients will have a diagnosis of COPD (postbronchodilator forced expiratory volume in 1 s/forced vital capacity ratio of <0.7). Two constant work rate exercise tests at 80% of the peak work rate will be carried out on two consecutive days with and without HFNT. The primary outcome will be the difference in endurance time between the two conditions. Secondary outcomes will be the change in muscle oxygenation during exercise, dyspnoea and muscle fatigue, respiratory muscle strength after exercise, respiratory rate, cardiac frequency, transcutaneous CO2pressure and pulsed O2saturation. Nineteen patients will be included. Data will be analysed as intention to treat by a blinded statistician.

Ethics and dissemination

Ethics approval has been obtained from the Ethics Committees Nord-Ouest III, Caen, France (N° ID RCB: 2016-A01325-46). The study will begin in April 2017 for a duration of 2 years. The results of the trial will be presented at national and international meetings and published in peer-reviewed journals.

Trial registration number

NCT03058081.
Meta-analysis using individual participant data from randomised trials: opportunities and limitations created by access to raw data
Authors: Rogozińska Ewelina , Marlin Nadine , Thangaratinam Shakila , Khan Khalid S , Zamora Javier
Published: August 2017

Meta-analysis based on individual participant data (IPD), often described as the ‘gold standard’ for effectiveness evidence synthesis, is increasingly being deployed despite being more resource intensive than collating study-level results. Its professed virtues include the ability to incorporate unreported data and to standardise variables and their definitions across trials. In reality, the unreported data, although present in shared datasets, might still not be usable in the analysis. The characteristics of trial participants and their outcomes may be too diversely captured for harmonisation and too time and resource consuming to standardise. Embarking on an IPD meta-analysis can lead to unanticipated challenges which ought to be handled with pragmatism. The aim of this article is to discuss the opportunities created by access to IPD and the practical limitations placed on such meta-analyses, using an international IPD meta-analysis of trials on the effect of lifestyle interventions in pregnancy as an example. Despite the increasing uptake of IPD meta-analysis, they encounter old problems shared by other research methods. When embarking on IPD meta-analysis, it is essential to evaluate the trade-offs between the ambitions, and what is achievable due to constraints imposed by the condition of collected IPD. Furthermore, incorporation of aggregate data from trials where IPD was not available should be a mandatory sensitivity analysis that makes the evidence synthesis up-to-date.
An analogy between socioeconomic deprivation level and loss of health from adverse effects of medical treatment in England
Authors: Lunevicius Raimundas , Haagsma Juanita A
Published: August 2017

Background

The purpose of this study was to show whether and how levels, trends and patterns obtained from estimates of premature deaths from adverse effects (AEs) of medical treatment depended on the deprivation level in England over the 24-year period, 1990–2013. We provide a report to inform decision-making strategies to reduce the burden of disease arising from AEs of medical treatment in the most deprived areas of the country.

Methods

Comparative analysis was driven by a single cause-of-injury category—AEs of medical treatment—from the Global Burden of Disease 2013 study. We report the mean values with 95% uncertainty intervals (UIs) for five socioeconomic deprivation areas of England.

Results

In the most deprived areas of England, the death rate declined from 2.27 (95% UI 1.65 to 2.57) to 1.54 (1.28 to 2.08) deaths (32.16% change). The death rate in the least deprived areas was 1.22 (0.88 to 1.38) in 1990; it was 1.17 (0.97 to 1.59) in 2013 (4.1% change). Regarding disability-adjusted life year (DALY) rates, the same trend is observed. Although the gap between the most deprived and least deprived populations of England narrowed with regards to number of deaths, and rates of deaths and DALYs from AEs of medical treatment, inequalities between marginal levels of deprivation remain.

Conclusions

The study suggests that a relationship between deprivation level and health loss from the AEs of medical treatment across England is possible. This could then be used when devising and prioritising health policies and strategies.
Retrospectively assessed physical work environment during working life and risk of sickness absence and labour market exit among older workers
Authors: Sundstrup Emil , Hansen Åse Marie , Mortensen Erik Lykke , Poulsen Otto Melchior , Clausen Thomas , Rugulies Reiner , Møller Anne , Andersen Lars L
Published: August 2017

Objective

To determine the prospective association between retrospectively assessed physical work environment during working life and prospectively assessed sickness absence and labour market exit among older workers.

Methods

Using Cox regression analyses we estimated the 4-year to 6-year prospective risk of register-based long-term sickness absence (LTSA), disability pension, early retirement and unemployment from exposure to different physical work environmental factors during working life among 5076 older workers (age 49–63 at baseline) from the Copenhagen Aging and Midlife Biobank cohort.

Results

Very hard physical work throughout working life was a risk factor for LTSA (HR 1.66,95% CI 1.32 to 2.07), disability pension (HR 2.21,95% CI 1.04 to 4.72) and early retirement (HR 1.57,95% CI 1.13 to 2.17). Both short-term (<10 years) and long-term (≥20 years) exposures to lifting or carrying of heavy burdens predicted the risk of LTSA (HRs 1.49–1.56) and disability pension (HRs 2.26–3.29). In contrast, exposure to dust was associated with LTSA and disability pension only following 20 or more exposure years.

Conclusions

Retrospectively assessed hard physical work during working life and exposure to several factors in the physical work environment, especially heavy lifting, were important for labour market exit and sickness absence. This study underscores the importance of reducing physical work exposures throughout the working life course for preventing sickness absence and premature exit from the labour market.
Do electronic cigarettes increase cigarette smoking in UK adolescents? Evidence from a 12-month prospective study
Authors: Conner Mark , Grogan Sarah , Simms-Ellis Ruth , Flett Keira , Sykes-Muskett Bianca , Cowap Lisa , Lawton Rebecca , Armitage Christopher J , Meads David , Torgerson Carole , West Robert , Siddiqi Kamran
Published: August 2017

Background

In cross-sectional surveys, increasing numbers of adolescents report using both electronic cigarettes (e-cigarettes) and cigarettes. This study assessed whether adolescent e-cigarette use was associated prospectively with initiation or escalation of cigarette use.

Methods

Data were from 2836 adolescents (aged 13–14 years at baseline) in 20 schools in England. At baseline, breath carbon monoxide levels, self-reported e-cigarette and cigarette use, sex, age, friends and family smoking, beliefs about cigarette use and percentage receiving free school meals (measure of socioeconomic status) were assessed. At 12-month follow-up, self-reported cigarette use was assessed and validated by breath carbon monoxide levels.

Results

At baseline, 34.2% of adolescents reported ever using e-cigarettes (16.0% used only e-cigarettes). Baseline ever use of e-cigarettes was strongly associated with subsequent initiation (n=1726; OR 5.38, 95% CI 4.02 to 7.22; controlling for covariates, OR 4.06, 95% CI 2.94 to 5.60) and escalation (n=318; OR 1.91, 95% CI 1.14 to 3.21; controlling for covariates, this effect became non-significant, OR 1.39, 95% CI 0.97 to 1.82) of cigarette use.

Conclusions

This is the first study to report prospective relationships between ever use of e-cigarettes and initiation and escalation of cigarette use among UK adolescents. Ever use of e-cigarettes was robustly associated with initiation but more modestly related to escalation of cigarette use. Further research with longer follow-up in a broader age range of adolescents is required.
Relationship between trying an electronic cigarette and subsequent cigarette experimentation in Scottish adolescents: a cohort study
Authors: Best Catherine , Haseen Farhana , Currie Dorothy , Ozakinci Gozde , MacKintosh Anne Marie , Stead Martine , Eadie Douglas , MacGregor Andy , Pearce Jamie , Amos Amanda , Frank John , Haw Sally
Published: August 2017

Background

This study examines whether young never smokers in Scotland, UK, who have tried an e-cigarette are more likely than those who have not, to try a cigarette during the following year.

Methods

Prospective cohort survey conducted in four high schools in Scotland, UK during February/March 2015 (n=3807) with follow-up 1 year later. All pupils (age 11–18) were surveyed. Response rates were high in both years (87% in 2015) and 2680/3807 (70.4%) of the original cohort completed the follow-up survey. Analysis was restricted to baseline ‘never smokers’ (n=3001/3807), 2125 of whom were available to follow-up (70.8%).

Results

At baseline, 183 of 2125 (8.6%) never smokers had tried an e-cigarette and 1942 had not. Of the young people who had not tried an e-cigarette at baseline, 249 (12.8%) went on to try smoking a cigarette by follow-up. This compares with 74 (40.4%) of those who had tried an e-cigarette at baseline. This effect remained significant in a logistic regression model adjusted for smoking susceptibility, having friends who smoke, family members’ smoking status, age, sex, family affluence score, ethnic group and school (adjusted OR 2.42 (95% CI 1.63 to 3.60)). There was a significant interaction between e-cigarette use and smoking susceptibility and between e-cigarette use and smoking within the friendship group.

Conclusions

Young never smokers are more likely to experiment with cigarettes if they have tried an e-cigarette. Causality cannot be inferred, but continued close monitoring of e-cigarette use in young people is warranted.
Combined aerobic and resistance exercise training for improving reproductive function in infertile men: a randomized controlled trial
Authors: Hajizadeh Maleki Behzad , Tartibian Bakhtyar
Published: August 2017

This randomized controlled trial was conducted to examine the effects of 24 weeks of combined aerobic and resistance exercise training on seminal markers of inflammation and oxidative stress as well as markers of male reproductive function and reproductive performance in infertile patients. Of a total of 1296 infertile patients (aged 25–40 years) who were screened, 556 were randomly assigned to exercise (n = 278) and nonexercise (n = 278) groups. Semen samples were taken before and at 12 and 24 weeks as well as 7 and 30 days post-intervention. The training program reduced seminal proinflammatory cytokines (interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor alpha) and markers of oxidative stress (reactive oxygen species, malondialdehyde, and 8-isoprostane) (P < 0.05). Additional improvements were also achieved in seminal antioxidant defense system (superoxide dismutase, catalase, and total antioxidant capacity) (P < 0.05). Training-induced changes in inflammation and oxidative stress status correlated with favorable improvements in semen parameters, sperm DNA integrity, and pregnancy rate (P < 0.05). In conclusion, these results support the evidence for the favorable effects of combined aerobic and resistance exercise training in male factor infertility.
Rapid and targeted introgression of fgr gene through marker-assisted backcrossing in rice (Oryza sativa L.)
Authors: Cheng Acga , Ismail Ismanizan , Osman Mohamad , Hashim Habibuddin , Mohd Zainual Nur Samahah
Published: August 2017

While it is crucial for developing countries like Malaysia to achieve self-sufficiency in rice (Oryza sativa L.), it is equally critical to be able to produce high-quality rice, specifically fragrant rice, which demands are often met through importation. The present study was aimed at developing high-yielding fragrant rice, in a timely and cost-effective manner. A marker-assisted backcross (MABC) approach was optimised to introgress the fragrance gene (fgr) into two high-yielding Malaysian varieties, MR84 and MR219, within two years utilising less than 50 molecular markers. Coupled with phenotypic screening, one single foreground marker (fgr-SNP) and 48 background markers were selected and utilised, revealing recovery of at least 90% of recurrent parent genome (RPG) in merely two backcross generations. Collectively, the yield potential of the developed BC2F2 lines (BLs) was higher (P > 0.05) than the donor parent, MRQ74, and similar (P < 0.05) to both the recurrent parents, MR84 and MR219. In addition, some of the developed BLs showed good grain quality, such as having long grain. We believe that this is the first report comprising the validation and utilisation of the single functional marker system (fgr-SNP) in introgressing the fgr gene into different rice varieties.
Quantum gravity at Hubble scales determines the cosmological constant and the amplitude of primordial perturbations
Authors: Padmanabhan T. , Padmanabhan Hamsa
Published: August 2017

Gravity controls the amount of information that is accessible to any specific observer. We quantify the notion of cosmic information (‘CosmIn’) for the case of an eternal observer in the universe. Demanding the finiteness of CosmIn requires the universe to have a late-time accelerated expansion phase. Combined with some generic features of the quantum structure of spacetime, this leads to the determination of (i) the numerical value of the cosmological constant, as well as (ii) the amplitude of the primordial, scale invariant perturbation spectrum in terms of a single free parameter, which specifies the energy scale at which the universe makes a transition from a pre-geometric phase to the classical phase. This formalism also shows that the quantum gravitational information content of spacetime can be tested by using precision cosmology.
FIRST-ORDER NETWORK COHERENCE AND EIGENTIME IDENTITY ON THE WEIGHTED CAYLEY NETWORKS
Authors: DAI MEIFENG , WANG XIAOQIAN , ZONG YUE , ZOU JIAHUI , CHEN YUFEI , SU WEIYI
Published: August 2017

In this paper, we first study the first-order network coherence, characterized by the entire mean first-passage time (EMFPT) for weight-dependent walk, on the weighted Cayley networks with the weight factor. The analytical formula of the EMFPT is obtained by the definition of the EMFPT. The obtained results show that the scalings of first-order coherence with network size obey four laws along with the range of the weight factor. Then, we study eigentime identity quantifying as the sum of reciprocals of all nonzero normalized Laplacian eigenvalues on the weighted Cayley networks with the weight factor. We show that all their eigenvalues can be obtained by calculating the roots of several small-degree polynomials defined recursively. The obtained results show that the scalings of the eigentime identity on the weighted Cayley networks obey two laws along with the range of the weight factor.
1/f Noise in Optical Output and Non-Gaussianity in Voltage Noise of GaAs Nanoscale Light-Emitting Structures
Authors: Belyakov Alexander V. , Klyuev Alexey V. , Yakimov Arkady V.
Published: August 2017

The 1/[Formula: see text] noise investigation in nanoscale light-emitting diodes (LEDs) and lasers, based on GaAs and its solid solutions, is presented here. Spectra of 1/[Formula: see text] noise [Formula: see text] in the voltage across terminals of device, and [Formula: see text] in emitted light intensity, as well as the cross-spectrum [Formula: see text], were measured. It was found that the noise in the leakage current, and in the additional nonlinear current, of devices is transformed into the noise in optical output intensity in spontaneous emission regime. We measured the histogram as the estimate of the probability density function of the voltage noise. The obtained data in lasers characterize the non-Gaussianity and/or nonstationarity of the noise in the regime of induced radiation. In contrast, in LEDs the deviation of noise from Gaussianity practically was not observed.
Research on the Evaluation Indicator System for Climate Adaptive Cities: A Case Study of Beijing
Authors: XIE Xinlu , ZHENG Yan
Published: August 2017

In recent years, the issue of what kinds of policies and practices cities should adopt to strengthen their resilience and climate adaptability has aroused remarkable interest among researchers in urban and environmental studies at home and abroad. The Chinese government has conducted a series of pilot programs in building climate-adaptive cities. A sound description and evaluation of the climate adaptability of a city, regardless of the size, provides the basis for adaptation planning and decision-making. Taking Beijing as an example, the authors analyze the adaptability of its subordinate 16 districts during the 2010–2014 period by establishing an indicator system for climate adaptability. The result shows imbalanced development in terms of economic support, level of social development, natural resources, technological support and risk management capacity of the districts in Beijing. The analysis also finds that the general adaptability is consistent with the city’s functional areas, indicating that function orientation of each district exerts potential influence on its development and adaptability. The core urban area boasts prominent advantages in general adaptability as it features a sound development basis. The newly developed area, facing such pressures as weak infrastructure, shortage of natural resource, and increasingly stringent requirements for environmental governance, shows the lowest general adaptability. The municipal government of the climate adaptive city should play its leading role in building the city’s climate resilience. More specifically, this calls for forward-looking adaptation planning that is aimed at improving the resilience and general adaptability of the city by facilitating coordinated development of different districts, and strengthening the functional complementarity and coordination between the city’s central and peripheral areas.
Feedback modulation of surrounding pressure determines the onset of negative effort dependence in a collapsible tube bench model of the pharyngeal airway
Authors: Lambeth Christopher , Kolevski Benjamin , Amis Terence , Kairaitis Kristina
Published: August 2017

Negative effort dependence (NED), decreased airflow despite increased driving pressure, has been proposed as a specific obstructive sleep apnea (OSA) phenotypic characteristic. We examined conditions under which NED occurs in a collapsible tube, pharyngeal airway bench model with the chamber enclosed, focusing on relationships with surrounding pressure levels and longitudinal strain. Using a vacuum source, graded airflows (V̇; 0–5 l/s) were generated through a thin-walled latex tube enclosed within a rigid, cylindrical chamber, sealed with initial chamber pressures (Pci) of 0–5 cmH2O (separate runs), or opened to the atmosphere. Upstream minus downstream pressure (Pu − Pd), maximum airflow (V̇max), and chamber pressure (Pc) were measured at 0–50% longitudinal strain. NED occurred across the range of Pci and strains studied but was most pronounced for the chamber open condition. With a sealed chamber, V̇ increased and Pc decreased with increasing Pu − Pd until the onset of NED at V̇max and a Pc value that was designated as critical (Pcc). Pcc was lowest (−17 cmH20) and V̇max was highest (~5 l/s) with chamber sealed: Pci = 0 cmH2O and 12.5 to 25% strain. We conclude that for our collapsible tube model, the achievable V̇max before the onset of NED depends on both the initial conditions (Pci and strain) and the dynamics of feedback between driving pressure and chamber pressure (chamber sealed vs. open). NED-based phenotypic analyses for OSA may need to focus on potential feedback control mechanisms (eg lung volume change, muscle activity) that may link peripharyngeal tissue pressure levels to driving pressures for airflow.

NEW & NOTEWORTHY A collapsible tube, pharyngeal airway bench model was used to study the role of surrounding pressure and longitudinal wall strain at the onset of negative effort dependence (NED). NED occurred to varying degrees across all conditions tested, but maximum airflow was achieved with 1) low initial surrounding pressure, 2) a feedback mechanism between surrounding pressure and driving pressure; and 3) a moderate amount of strain applied. Potential impacts on OSA phenotypic analyses are discussed.
Effects of antenatal melatonin therapy on lung structure in growth-restricted newborn lambs
Authors: Polglase Graeme R. , Barbuto Jade , Allison Beth J. , Yawno Tamara , Sutherland Amy E. , Malhotra Atul , Schulze Keith E. , Wallace Euan M. , Jenkin Graham , Ricardo Sharon D. , Miller Suzanne L.
Published: August 2017

Oxidative stress arising from suboptimal placental function contributes to a multitude of pathologies in infants compromised by fetal growth restriction (FGR). FGR infants are at high risk for respiratory dysfunction after birth and poor long-term lung function. Our objective was to investigate the contribution of oxidative stress to adverse lung development and the effects of melatonin administration, a powerful antioxidant, on lung structure in FGR lambs. Placental insufficiency and FGR was surgically induced in 13 fetal sheep at ∼105 days of gestation by ligation of a single umbilical artery. Maternal intravenous melatonin infusion was commenced in seven of the ewes 4 h after surgery and continued until birth. Lambs delivered normally at term and lungs were collected 24 h after birth for histological assessment of lung structure and injury and compared with appropriately grown control lambs ( n = 8). FGR fetuses were hypoxic and had lower glucose during gestation compared with controls. Melatonin administration prevented chronic hypoxia. Within the lung, FGR caused reduced secondary septal crest density and altered elastin deposition compared with controls. Melatonin administration had no effect on the changes to lung structure induced by FGR. We conclude that chronic FGR disrupts septation of the developing alveoli, which is not altered by melatonin administration. These findings suggest that oxidative stress is not the mechanism driving altered lung structure in FGR neonates. Melatonin administration did not prevent disrupted airway development but also had no apparent adverse effects on fetal lung development.

NEW & NOTEWORTHY Fetal growth restriction (FGR) results in poor respiratory outcomes, which may be caused by oxidation in utero. We investigated the contribution of oxidative stress to adverse lung development and the effects of melatonin administration, a powerful antioxidant, on lung structure in FGR lambs. FGR disrupted septation of the developing alveoli, which is not altered by melatonin administration. Oxidative stress may not be the mechanism driving altered lung structure in FGR neonates.
Endothelial Progenitor Cells for Ischemic Stroke: Update on Basic Research and Application
Authors: Liao Shaohua , Luo Chunxia , Cao Bingzhen , Hu Huaiqiang , Wang Suxia , Yue Huili , Chen Lin , Zhou Zhenhua
Published: August 2017

Ischemic stroke is one of the leading causes of human death and disability worldwide. So far, ultra-early thrombolytic therapy is the most effective treatment. However, most patients still live with varying degrees of neurological dysfunction due to its narrow therapeutic time window. It has been confirmed in many studies that endothelial progenitor cells (EPCs), as a kind of adult stem cells, can protect the neurovascular unit by repairing the vascular endothelium and its secretory function, which contribute to the recovery of neurological function after an ischemic stroke. This paper reviews the basic researches and clinical trials of EPCs especially in the field of ischemic stroke and addresses the combination of EPC application with new technologies, including neurovascular intervention, synthetic particles, cytokines, and EPC modification, with the aim of shedding some light on the application of EPCs in treating ischemic stroke in the future.
Can Mixed Parasite Infections Thwart Targeted Malaria Elimination Program in India?
Authors: Singh Upasana Shyamsunder , Siwal Nisha , Pande Veena , Das Aparup
Published: August 2017

India is highly endemic to malaria with prevalence of all five species of human malaria parasites ofPlasmodiumgenus. India is set for malaria elimination by 2030. Since cases of mixedPlasmodiumspecies infections remain usually undetected but cause huge disease burden, in order to understand the distributional prevalence of both monospecies infections and mixed species infections in India, we collated published data on the differential infection incidences of the five different malaria parasites based on PCR diagnostic assay. About 11% of total cases were due to mixed species infection. Among several interesting observations on both single and mixed parasitic infections, incidences ofPlasmodium falciparummonoinfection were found to be significantly higher thanP. vivaxmonoinfection. Also,P. malariaeseems to be emerging as a potential malaria threat in India. Putting all the facts together, it appears that the dream of achieving malaria elimination in India will not be completely successful without dealing with mixed species infection.
Aquatic Plant Genomics: Advances, Applications, and Prospects
Authors: Hu Shiqi , Li Gaojie , Yang Jingjing , Hou Hongwei
Published: August 2017

Genomics is a discipline in genetics that studies the genome composition of organisms and the precise structure of genes and their expression and regulation. Genomics research has resolved many problems where other biological methods have failed. Here, we summarize advances in aquatic plant genomics with a focus on molecular markers, the genes related to photosynthesis and stress tolerance, comparative study of genomes and genome/transcriptome sequencing technology.
The Role of Physicians in Rationing Cancer Care. Attitudes of German Oncologists
Authors: Fernau Sandra , Mehlis Katja , Schildmann Jan , Krause Stefan , Winkler Eva C.
Published: August 2017

Background: Against the background of limited resources, the rise in the cost of therapy as well as in the number of cancer patients fuels the discussion about the necessity to ration, i.e., setting limits to beneficial treatment for cost reasons. Recently, we presented the self-reported prevalence of bedside rationing among German oncologists. Here, we describe oncologists' views on cost containment strategies and their role therein. Methods: We performed an online survey including structured questions and free field sections with the members of the German Society of Hematology and Oncology. Results: In the perception of oncologists, cost considerations and negotiations are gaining in importance and consume considerable working time. This negatively affects job satisfaction in 72% of the 345 respondents. Oncologists are concerned that the quality of care will suffer from rationalization and implicit rationing. They are ambivalent as to who is best suited to decide about resource rationing: 66% support the view that limits for costly procedures should be set by a form of commission; nevertheless, 48% consider physicians as the best decision makers in these situations. Conclusion: We suggest a broad public discussion and an interdisciplinary debate among the oncology community to define and legitimize decisions on rationing by setting explicit criteria.
CARTs for Solid Tumors: Feasible or Infeasible?
Authors: Li Wei , Song Xiujun , Jin Yanwen , Li Fengsheng , Yu Huijie , Cao Cheng , Jiang Qisheng
Published: August 2017

Adoptive transfer of chimeric antigen receptor-engineered T cells (CARTs) is a novel approach to cancer therapy as CARTs combine with the antigen specificity of an antibody and the activating functions of T lymphocytes. Recent results from preclinical and clinical trials with CARTs for B-cell malignancies are exciting, although different groups selected different tumor-associated antigens, binding domains, and signal domains, which make up the chimeric antigen receptor (CAR) configuration. However, there are few clinical trials with CARTs for solid tumors compared to hematologic malignancies. In this brief review, we discuss the basic principles of CAR design and clinical studies of CARTs for solid tumors.