bluuebunny/crossref_metadata_2025 huggingface dataset:
Reaction–diffusion basis of retroviral infectivity
Authors: Sadiq S. Kashif
Published: October 2016

Retrovirus particle (virion) infectivity requires diffusion and clustering of multiple transmembrane envelope proteins (Env
3
) on the virion exterior, yet is triggered by protease-dependent degradation of a partially occluding, membrane-bound Gag polyprotein lattice on the virion interior. The physical mechanism underlying such coupling is unclear and only indirectly accessible via experiment. Modelling stands to provide insight but the required spatio-temporal range far exceeds current accessibility by all-atom or even coarse-grained molecular dynamics simulations. Nor do such approaches account for chemical reactions, while conversely, reaction kinetics approaches handle neither diffusion nor clustering. Here, a recently developed multiscale approach is considered that applies an ultra-coarse-graining scheme to treat entire proteins at near-single particle resolution, but which also couples chemical reactions with diffusion and interactions. A model is developed of Env
3
molecules embedded in a truncated Gag lattice composed of membrane-bound matrix proteins linked to capsid subunits, with freely diffusing protease molecules. Simulations suggest that in the presence of Gag but in the absence of lateral lattice-forming interactions, Env
3
diffuses comparably to Gag-absent Env
3
. Initial immobility of Env
3
is conferred through lateral caging by matrix trimers vertically coupled to the underlying hexameric capsid layer. Gag cleavage by protease vertically decouples the matrix and capsid layers, induces both matrix and Env
3
diffusion, and permits Env
3
clustering. Spreading across the entire membrane surface reduces crowding, in turn, enhancing the effect and promoting infectivity.

This article is part of the themed issue ‘Multiscale modelling at the physics–chemistry–biology interface’.
Multiscale simulation of molecular processes in cellular environments
Authors: Chiricotto Mara , Sterpone Fabio , Derreumaux Philippe , Melchionna Simone
Published: October 2016

We describe the recent advances in studying biological systems via multiscale simulations. Our scheme is based on a coarse-grained representation of the macromolecules and a mesoscopic description of the solvent. The dual technique handles particles, the aqueous solvent and their mutual exchange of forces resulting in a stable and accurate methodology allowing biosystems of unprecedented size to be simulated.

This article is part of the themed issue ‘Multiscale modelling at the physics–chemistry–biology interface’.
Rapid molecular detection of Zika virus in urine using the recombinase polymerase amplification assay
Authors: El Wahed Ahmed Abd , Sanabani Sabri S. , Faye Oumar , Pessôa Rodrigo , Patriota João Veras , Giorgi Ricardo Rodrigues , Patel Pranav , Böhlken-Fascher Susanne , Landt Olfert , Niedrig Matthias , Paolo M. de A. Zanotto , Czerny Claus-Peter , Sall Amadou A. , Weidmann Manfred
Published: October 2016

Background

Currently the detection of Zika virus (ZIKV) in patient samples is done by real-time RT-PCR. Samples collected from rural area are sent to highly equipped laboratories for screening. A rapid point-of-care test is needed to detect the virus, especially at low resource settings.

Methodology/Principal Findings

In this report, we describe the development of a reverse transcription isothermal recombinase polymerase amplification (RT-RPA) assay for the identification of ZIKV. RT-RPA assay was portable, sensitive (21 RNA molecules), and rapid (3-15 minutes). No cross-reactivity was detected to other flaviviruses, alphaviruses and arboviruses. Compared to real-time RT-PCR, the diagnostic sensitivity was 92%, while the specificity was 100%.

Conclusions/Significance

The developed assay is a promising platform for rapid point of need detection of ZIKV in low resource settings and elsewhere (e.g. during mass gathering).

Author Summary

Currently, Dengue (DENV), Zika (ZIKV) and Chikungunya (CHIKV) viruses represent a global threat. The clinical picture of the acute febrile diseases caused by DENV, ZIKV and CHIKV is very similar, in addition, the same mosquito vector is involved in the transmission cycle. The differentiation between them is of great importance as supportive treatment differs and the identification of any of the three viruses prompts implementation of control measures to avoid spreading of an outbreak. We have developed an assay for the detection of ZIKV genome. The assay based on isothermal “recombinase polymerase amplification” assay, which was performed at one temperature (42°C). The result was obtained in maximum of 15 minutes. Moreover, the assay is easy to be implemented at low resource settings.
I TRIED A BUNCH OF THINGS: THE DANGERS OF UNEXPECTED OVERFITTING IN CLASSIFICATION
Authors: Powell Michael , Hosseini Mahan , Collins John , Callahan-Flintoft Chloe , Jones William , Bowman Howard , Wyble Brad
Published: October 2016

Machine learning is a powerful set of techniques that has enhanced the abilities of neuroscientists to interpret information collected through EEG, fMRI, and MEG data. With these powerful techniques comes the danger ofoverfitting of hyper-parameterswhich can render results invalid, and cause a failure to generalize beyond the data set. We refer to this problem as‘over-hyping’and show that it is pernicious despite commonly used precautions. In particular, over-hyping occurs when an analysis is run repeatedly with slightly different analysis parameters and one set of results is selected based on the analysis. When this is done, the resulting method is unlikely to generalize to a new dataset, rendering it a partially, or perhaps even completely spurious result that will not be valid outside of the data used in the original analysis. While it is commonly assumed that cross-validation is an effective protection against such spurious results generated through overfitting or overhyping, this is not actually true. In this article, we show that both one-shot and iterative optimization of an analysis are prone to over-hyping, despite the use of cross-validation. We demonstrate that non-generalizable results can be obtained even on non-informative (i.e. random) data by modifying hyper-parameters in seemingly innocuous ways. We recommend a number of techniques for limiting over-hyping, such as lock-boxes, blind analyses, pre-registrations, and nested cross-validation. These techniques, are common in other fields that use machine learning, including computer science and physics. Adopting similar safeguards is critical for ensuring the robustness of machine-learning techniques in the neurosciences.
Dimethylammonium 2,4,5-tricarboxybenzoate: an example of the decarbonylation of N,N-dimethylformamide in the presence of a metal and a benzenepolycarboxylic acid. Is zirconium(IV) the Tsotsi?
Authors: Hulushe S. T. , Hosten E. C. , Watkins G. M.
Published: October 2016

The title salt, C2H8N+·C10H5O8
−, was the unexpected product of an attempt to prepare a ZrIV metal–organic framework with benzene-1,2,4,5-tetracarboxylic acid (1,2,4,5-H3B4C). In the reaction, the DMF solvent has been decarbonylated, forming the dimethylammonium cation, with one proton lost from the tetracarboxylic acid. It is proposed that the ZrIV salt acts as a Tsotsi or robber, plundering CO from the DMF molecule. The resulting salt crystallizes with two cations and two anions in the asymmetric unit. An intramolecular hydrogen bond forms between a carboxylic acid substituent and the carboxylate group of each of the monodeprotonated (1,2,4,5-H3B4C−) anions. In the crystal, an extensive array of O—H...O, N—H...O and C—H...O hydrogen bonds generates a three-dimensional network, with columns of cations and anions forming along the b axis.
Diethyl 2,2′-bipyridine-4,4′-dicarboxylate
Authors: Rillema D. Paul , Moore Curtis , KomReddy Venugopal
Published: October 2016

The title bipyridine derivative, C16H16N2O4, crystallized with two half molecules in the asymmetric unit. The whole molecules (A and B) are generated by inversion symmetry with the mid-points of the bridging C—C bonds of the bipyridine units being located on crystallographic inversion centers. In the crystal, molecules are linked by C—H...O hydrogen bonds, forming sheets parallel to (120). The sheets are linked by C—H...N hydrogen bonds, forming a three-dimensional framework.
Bioaccessibility of Fukushima‐Accident‐Derived Cs in Soils and the Contribution of Soil Ingestion to Radiation Doses in Children
Authors: Takahara Shogo , Ikegami Maiko , Yoneda Minoru , Kondo Hitoshi , Ishizaki Azusa , Iijima Masashi , Shimada Yoko , Matsui Yasuto
Published: October 2016

Ingestion of contaminated soil is one potential internal exposure pathway in areas contaminated by the Fukushima Daiichi Nuclear Power Plant accident. Doses from this pathway can be overestimated if the availability of radioactive nuclides in soils for the gastrointestinal tract is not considered. The concept of bioaccessibility has been adopted to evaluate this availability based on in vitro tests. This study evaluated the bioaccessibility of radioactive cesium from soils via the physiologically‐based extraction test (PBET) and the extractability of those via an extraction test with 1 mol/L of hydrochloric acid (HCl). The bioaccessibility obtained in the PBET was 5.3% ± 1%, and the extractability in the tests with HCl was 16% ± 3%. The bioaccessibility was strongly correlated with the extractability. This result indicates the possibility that the extractability in HCl can be used as a good predictor of the bioaccessibility with PBET. In addition, we assessed the doses to children from the ingestion of soil via hand‐to‐mouth activity based on our PBET results using a probabilistic approach considering the spatial distribution of radioactive cesium in Date City in Fukushima Prefecture and the interindividual differences in the surveyed amounts of soil ingestion in Japan. The results of this assessment indicate that even if children were to routinely ingest a large amount of soil with relatively high contamination, the radiation doses from this pathway are negligible compared with doses from external exposure owing to deposited radionuclides in Fukushima Prefecture.
On the double Laplace transform of the truncated variation of a Brownian motion with drift
Authors: Łochowski Rafał Marcin
Published: October 2016

The aim of this paper is to find a formula for the double Laplace transform of the truncated variation of a Brownian motion with drift. In order to find the double Laplace transform, we also prove some identities for the Brownian motion with drift, which may be of independent interest.
A Human-Centered Design of General-Purpose Unmanned Electric Vehicle Chassis for Agriculture Task Payload
Authors: Ma Kuang , Qi Ziming
Published: October 2016

This paper presents the design process of a novel general-purpose electric vehicle chassis as agriculture payload carrier platform to perform agricultural tasks: detection, guidance, mapping, and action. This design applied a human-centered design frameworks and processes: Kumar's seven modes of the design innovation process, and the three lenses of human-centered design by IDEO. After approach from three design-project perspectives mapping, a universal electric-powered multiwheel independent drive and independent steering robotic vehicle platform is designed for agricultural application. A real size prototype has been built to prove the design.
Loss Mechanisms of Interplatform Steps in a 1.5-Stage Axial Flow Turbine
Authors: Kluxen Robert , Behre Stephan , Jeschke Peter , Guendogdu Yavuz
Published: October 2016

In this paper, the detailed steady and unsteady numerical investigations of a 1.5-stage axial flow turbine are conducted to determine the specific influence of interplatform steps in the first stator—as caused by deviations in manufacturing or assembly. A basic first stator design and a design consisting of a bow and endwall contours are compared. Apart from step height, the position and geometry of the interplatform border are varied for the basic design. To create the steps, every third stator vane was elevated, together with its platforms at hub and shroud, such that the flow capacity is only little affected. The results show that the effects of steps on the platform borders in front and aft of the first stator can be decoupled from those occurring on the interplatform steps. For the latter, being the main contributor to the additional loss, the intensity of recirculation zones and losses increase substantially when the platform border is located close to the suction side. Using a relative step height of 1.82% span, the entropy production doubles when compared to a position close to the pressure side, which can be explained by differences in local flow velocity level. Regarding a circular-arc-shaped platform, the losses can be more than halved—mainly due to lower included angles between step and endwall flow streamlines. The findings can be explained by a nondimensional relation of the local entropy production using local values for step height and characteristic flow quantities. Furthermore, a reduction in step height leads to an attenuation of the otherwise linear relationship between step height and entropy production, which is mainly due to lower local ratio of step height and boundary layer thickness. In the case of laminar or transitional flow regions on the endwall, typical for turbine rigs with low inlet turbulence and low-pressure turbines under cruise conditions, the steps lead to immediate local flow transition and thus substantially different results.
Investigation of Optimum Refrigerant Charge and Fans' Speed for a Vehicle Air Conditioning System
Authors: Bagheri Farshid , Ali Fayazbakhsh M. , Bahrami Majid
Published: October 2016

In this study, the performance evaluation and optimization of a recently developed battery-powered vehicle air conditioning (BPVAC) system is investigated. A mathematical model is developed to simulate the thermodynamic and heat transfer characteristics of the BPVAC system and calculate the coefficient of performance (COP). Utilizing environmental chambers and a number of measuring equipment, an experimental setup is built to validate the model accuracy and to conduct performance optimization by changing the charge of refrigerant in the system. The model is validated and employed for performance simulation and optimization in a wide range of speed for the evaporator and condenser fans. The modeling results verify that for any operating condition an optimum performance can be achieved by adjusting the speed of condenser and evaporator fans. The optimum refrigerant charge is obtained, and a potential improvement of 10.5% is calculated for the performance of system under ANSI/AHRI 210/240-2008 specifications.
Investigation of Vortical Structures and Turbulence Characteristics in Corner Separation in a Linear Compressor Cascade Using DDES
Authors: Liu Yangwei , Yan Hao , Lu Lipeng , Li Qiushi
Published: October 2016

Three-dimensional (3D) corner separation in a linear highly loaded compressor cascade is studied by using delayed detached-eddy simulation (DDES) method. This paper studies the flow mechanism of corner separation, including vortical structures and turbulence characteristics. The vortical structures are analyzed and the distributions of Reynolds stresses and turbulent anisotropy are also discussed in detail. The results show that there exist different kinds of vortical structures, such as horseshoe vortex, passage vortex, wake shedding vortex, and “corner vortex.” Before the corner separation forms, the passage vortex becomes the main secondary vortex and obviously enhances the corner separation. At approximate 35% chord position, the corner vortex begins to form, enlarges rapidly, and dominates the secondary flow in the cascade. The corner vortex is a compound vortex with its vortex core composed of multiple vortices. Streamwise normal Reynolds stress contributes greatest to the turbulence fluctuation in the corner region. The turbulence develops from two-dimensional (2D) turbulence in the near-wall region to one-component type turbulence in the corner region. The turbulence tends to be more anisotropic when the flow is close to the endwall within the corner separation region.
Hydraulic Loss of Finite Length Dividing Junctions
Authors: Tomor András , Kristóf Gergely
Published: October 2016

A general hydraulic loss coefficient correlation for perpendicular, cylindrical, finite length dividing pipe junctions is developed and implemented in a discrete dividing-flow manifold model. Dividing-flow manifolds are used in several technical appliances, e.g., in water and wastewater treatment, swimming pool technology, air engineering, and polymer processing. Ensuring uniform flow distribution is a major goal of a flow manifold system design, whose accuracy is usually determined by the accuracies of applied flow coefficients. Coefficient of turning losses is calculated by a computational fluid dynamics (CFD)-based approach applying a nonlinear fit. In the case of a single-phase flow, the loss coefficient depends on four dimensionless parameters: the Reynolds number, the ratio of port and header flow velocities, the diameter ratio, and the ratio of the port length and the diameter of the pipe. Instead of experimentally covering this four-dimensional parameter space, more than 1000 judiciously chosen three-dimensional simulations were run to determine the loss coefficient for the parameter range most used in engineering practice. Validated results of our novel resistance formula show that the velocity and port length to header diameter ratios have a significant effect on the turning loss coefficient, while the diameter ratio and Reynolds number dependency are weaker in the investigated parameter ranges.
A Laparoscopic Morcellator Redesign to Constrain Tissue Using Integrated Gripping Teeth
Authors: Arkenbout E. A. , van den Haak L. , Penning M. , Rog E. , Vierwind A. , van Cappelle L. E. , Jansen F. W. , de Winter J. C. F.
Published: October 2016

Laparoscopic hysterectomy is a procedure that involves the removal of the uterus through an abdominal keyhole incision. Morcellators have been specifically designed for this task, but their use has been discouraged by the food and drug administration (FDA) since November 2014 because of risks of cancerous tissue spread. The use of laparoscopic bags to catch and contain tissue debris has been suggested, but this does not solve the root cause of tissue spread. The fundamental problem lies in the tendency of the tissue mass outside the morcellation tube to rotate along with the cutting blade, causing tissue to be spread through the abdomen. This paper presents a bio-inspired concept that constrains the tissue mass in the advent of its rotation in order to improve the overall morcellation efficacy and reduce tissue spread. A design of gripping teeth integrated into the inner diameter of the morcellation tube is proposed. Various tooth geometries were developed and evaluated through an iterative process in order to maximize the gripping forces of these teeth. The maximum gripping force was determined through the measurement of force–displacement curves during the gripping of gelatin and bovine tissue samples. The results indicate that a tooth ring with a diameter of 15 mm can provide a torque resistance of 1.9 Ncm. Finally, a full morcellation instrument concept design is provided.
Simplified Kinematics for a Parallel Manipulator Generator of the Schönflies Motion
Authors: Gallardo-Alvarado Jaime , Abedinnasab Mohammad H. , Lichtblau Daniel
Published: October 2016

This work is devoted to simplify the inverse–forward kinematics of a parallel manipulator generator of the 3T1R motion. The closure equations of the displacement analysis are formulated based on the coordinates of two points embedded in the moving platform. Afterward, five quadratic equations are solved by means of a novel method based on Gröbner bases endowed with first-order perturbation and local stability of parameters. Meanwhile, the input–output equations of velocity and acceleration are systematically obtained by resorting to reciprocal-screw theory. In that concern, the inclusion of pseudokinematic pairs connecting the limbs to the fixed platform and a passive kinematic chain to the robot manipulator allows to avoid the handling of rank-deficient Jacobian matrices. The workspace of the robot is determined by using a discretized method associated to its inverse–forward displacement analysis, whereas the singularity analysis is approached based on the input–output equation of velocity. Numerical examples are provided with the purpose to show the application of the method.
Accelerated Cryogenic Cooling Caused by the Temporary Frost Layer Enhancer
Authors: Mazor Gedalya , Ladizhensky Izhak , Nemirovsky Dmitry , Alfi Alon , Rabin Andrei , Yehud Elad , Korin Eli
Published: October 2016

The possibility of using a frost layer, created on the surface of a sample that undergoes cryogenic treatment, as a heat transfer enhancer was recently studied. This layer grows on the preliminary cooled sample surface as a result of its contact with moist air flow prior to its immersion into liquid nitrogen. A significant increase in the outflow heat flux (up to 12.8 times), or, alternatively, a cooling time shortening, in comparison with the bare sample was found. A detailed description of the frost layer development along with the influence of the thickness of the layer on the efficiency of the cooling process, as well as environmental parameters that affect the thickness itself is presented in the paper.
Broadband acoustic backscatter from crude oil under laboratory-grown sea ice
Authors: Bassett Christopher , Lavery Andone C. , Maksym Ted , Wilkinson Jeremy P.
Published: October 2016

In ice-covered seas, traditional air-side oil spill detection methods face practical challenges. Conversely, under-ice remote sensing techniques are increasingly viable due to improving operational capabilities of autonomous and remotely operated vehicles. To investigate the potential for under-ice detection of oil spills using active acoustics, laboratory measurements of high-frequency, broadband backscatter (75–590 kHz) from crude oil layers (0.7–8.1 cm) under and encapsulated within sea ice were performed at normal and 20° incidence angles. Discrete interfaces (water-oil, oil-ice, and ice-oil) are identifiable in observations following oil injections under the ice and during the subsequent encapsulation. A one-dimensional model for the total normal incidence backscatter from oil under ice, constrained by oil sound speed measurements from −10  °C to 20  °C and improved environmental measurements compared to previous studies, agrees well with pre-encapsulation observations. At 20° incidence angles echoes from the ice and oil under ice are more complex and spatially variable than normal incidence observations, most likely due to interface roughness and volume inhomogeneities. Encapsulated oil layers are only detected at normal incidence. The results suggest that high-frequency, broadband backscatter techniques may allow under-ice remote sensing for the detection and quantification of oil spills.
Comparative Pharmacokinetic Profiling of Different Polymyxin B Components
Authors: Manchandani Pooja , Dubrovskaya Yanina , Gao Song , Tam Vincent H.
Published: October 2016

Polymyxin B is increasingly used as a treatment of last resort for multidrug-resistant Gram-negative infections. Despite being available as a mixture of several structurally related analogues, the properties are commonly reported as an aggregate of the individual components. We compared the pharmacokinetics of individual polymyxin B components in an animal model and in humans. There were no considerable differences observed in the pharmacokinetics among major components of polymyxin B. Combining different components for pharmacokinetic analysis appeared reasonable.
Aortic valve replacement for Libman-Sacks endocarditis
Authors: Keenan Jack B , Janardhanan Rajesh , Larsen Brandon T , Khalpey Zain
Published: October 2016

A 24-year-old man with systemic lupus erythematosus and antiphospholipid syndrome complicated by lupus nephritis presented with acute limb ischaemia secondary to an embolus. Following embolectomy, the patient underwent a transthoracic echocardiogram which revealed a large vegetation on all three cusps of the aortic valve. The patient was taken for an urgent aortic valve replacement with a mechanical valve. Cultures of one cusp remained sterile. Histopathological examination of the remaining two cusps revealed sterile fibrin-rich thrombotic vegetations characteristic of non-bacterial thrombotic endocarditis.
Comparing the effectiveness of a crowdsourced video and a social marketing video in promoting condom use among Chinese men who have sex with men: a study protocol
Authors: Liu Chuncheng , Mao Jessica , Wong Terrence , Tang Weiming , Tso Lai Sze , Tang Songyuan , Zhang Ye , Zhang Wei , Qin Yilu , Chen Zihuang , Ma Wei , Kang Dianming , Li Haochu , Liao Meizhen , Mollan Katie , Hudgens Michael , Bayus Barry , Huang Shujie , Yang Bin , Wei Chongyi , Tucker Joseph D
Published: October 2016

Introduction

Crowdsourcing has been used to spur innovation and increase community engagement in public health programmes. Crowdsourcing is the process of giving individual tasks to a large group, often involving open contests and enabled through multisectoral partnerships. Here we describe one crowdsourced video intervention in which a video promoting condom use is produced through an open contest. The aim of this study is to determine whether a crowdsourced intervention is as effective as a social marketing intervention in promoting condom use among high-risk men who have sex with men (MSM) and transgender male-to-female (TG) in China.

Method

We evaluate videos developed by crowdsourcing and social marketing. The crowdsourcing contest involved an open call for videos. Entries were judged on capacity to promote condom use, to be shareable or ‘go viral’ and to give value to the individual. 1170 participants will be recruited for the randomised controlled trial. Participants need to be MSM age 16 and over who have had condomless anal sex in the last 3 months. Recruitment will be through an online banner ad on a popular MSM web page and other social media platforms. After completing an initial survey, participants will be randomly assigned to view either the social marketing video or the crowdsourcing video. Follow-up surveys will be completed at 3 weeks and 3 months after initial intervention to evaluate condomless sex and related secondary outcomes. Secondary outcomes include condom social norms, condom negotiation, condom self-efficacy, HIV/syphilis testing, frequency of sex acts and incremental cost.

Ethics and dissemination

Approval was obtained from the ethical review boards of the Guangdong Provincial Center for Skin Diseases and STI Control, UNC and UCSF. The results of this trial will be made available through publication in peer-reviewed journals.

Trial registration number

NCT02516930.
Identifying different typologies of experiences and coping strategies in men with rheumatoid arthritis: a Q-methodology study
Authors: Flurey Caroline A , Hewlett Sarah , Rodham Karen , White Alan , Noddings Robert , Kirwan John R
Published: October 2016

Objective

To identify typologies of experiences and coping strategies of men with rheumatoid arthritis (RA).

Design

Q-methodology (a qualitative and quantitative approach to grouping people according to their subjective opinion). Men with RA sorted 64 statements relating to their experience of living with RA according to level of agreement across a normal distribution grid. Data were examined using Q-factor analysis.

Setting

Rheumatology outpatient departments in the UK.

Participants

30 of 65 invited men with RA participated in this study (46%).

Results

All participants ranked highly the need to be well informed about their medication and the importance of keeping a positive attitude. 2 factors describing the experiences and coping strategies of male patients living with RA were identified: factor A: ‘acknowledge, accept and adapt’ (n=14) take a proactive approach to managing the impact of RA and find different ways of doing things; while factor B: ‘trying to match up to a macho ideal’ (n=8) are determined to continue with their pre-RA lives, and therefore push themselves to carry on even if this causes them pain. They are frustrated and angry due to the impact of RA but they internalise this rather than directing it at others.

Conclusions

While some men adapt to their RA by renegotiating their masculine identity, others struggle to relinquish their traditional masculine roles. Further research is needed to identify whether the finding that there are 2 distinct groups of men with RA can be generalised, and if so whether the differences can be explained by clinical, social or psychological factors, which may inform different therapeutic approaches.
Assessment for the possibility of a first night effect for wrist actigraphy in adolescents
Authors: Arora Teresa , Omar Omar M , Taheri Shahrad
Published: October 2016

Objectives

Evidence of a ‘first night effect’ has been documented for polysomnography. The possibility of this has not been previously assessed in wrist actigraphy, yet may have important implications for the study design of future sleep research. We sought to examine potential evidence of a ‘first night effect’ for wrist actigraphy in adolescents across weekdays and weekend nights for multiple sleep outcomes.

Design

3-year prospective cohort study (Midlands Adolescent Schools Sleep Education Study).

Setting

8 secondary schools in the Midlands region of the UK.

Participants

Adolescents (aged 11–13 years at baseline) were recruited to the study and were requested to wear a wrist actigraph for 7 consecutive days/nights at baseline and then annually for 2 years during the second term of the academic year.

Primary outcome measures

We compared multiple sleep outcomes (total sleep time, wake after sleep onset, sleep efficiency, sleep onset latency, number of awakenings, length of awakenings, sleep onset time) when the device was worn on a weekday and weekend and compared these to other nights to identify possible evidence of a ‘first night effect’ for wrist actigraphy.

Results

No significant differences were found between any sleep outcomes when the first night of wrist actigraphy was on a weekday compared with other weekdays. When the first night was measured on a weekend (Friday), average total sleep time was significantly greater (486±5 min) compared with the second night (Saturday; 469±6 min), p=0.01.

Conclusions

We found no evidence to support a ‘first night effect’ for wrist actigraphy in our adolescent sample. The first night of actigraphy data should not be disregarded in future studies that deploy this technique to measure sleep over prolonged time periods.
Association between occupational physical activity and myocardial infarction: a prospective cohort study
Authors: Johnsen Anna M , Alfredsson Lars , Knutsson Anders , Westerholm Peter J M , Fransson Eleonor I
Published: October 2016

Objective

Recommendations regarding physical activity typically include both leisure time and occupational physical activity. However, the results from previous studies on occupational physical activity and the association with myocardial infarction have been inconsistent. The aim of this study was to investigate if occupational physical activity is associated with the risk of myocardial infarction.

Design

Prospective cohort study.

Participants

Data from the Swedish Work, Lipids and Fibrinogen (WOLF) study was used, comprising 9961 employees (6849 men, 3112 women, mean age 42.7 years) having no history of myocardial infarction. The participants were categorised into 3 groups according to their level of occupational physical activity.

Outcome

Data regarding incident myocardial infarction were obtained from the Swedish National Patient Register and the Cause of Death Register. Cox proportional hazard regression was used for estimation of HRs for different levels of occupational physical activity in relation to the risk of myocardial infarction.

Results

During a mean follow-up of 13.1 years, 249 cases of incident myocardial infarction were identified. In analyses adjusted for age, sex and socioeconomic status, participants standing and walking more than 50% of their working day had an HR of 1.13 (95% CI 0.83 to 1.54), compared with participants seated more than 50% of their working day. The corresponding HR for participants whose work included lifting or carrying was 0.86 (95% CI 0.59 to 1.24). Further adjustment did not alter the results. Stratified analyses resulted in a significantly decreased risk for young people whose work included lifting or carrying, HR 0.37 (95% CI 0.17 to 0.84), compared with younger persons who sat most of their working day.

Conclusions

No significant association between occupational physical activity and the risk of myocardial infarction was observed in the total group of employees in this study. Based on the results from this study, occupational physical activity in general does not seem to be enough for reducing the risk of myocardial infarction.
The Baby Moves prospective cohort study protocol: using a smartphone application with the General Movements Assessment to predict neurodevelopmental outcomes at age 2 years for extremely preterm or extremely low birthweight infants
Authors: Spittle AJ , Olsen J , Kwong A , Doyle LW , Marschik PB , Einspieler C , Cheong JLY
Published: October 2016

Introduction

Infants born extremely preterm (EP; <28 weeks' gestation) and/or with extremely low birth weight (ELBW; <1000 g birth weight) are at increased risk for adverse neurodevelopmental outcomes. However, it is challenging to predict those EP/ELBW infants destined to have long-term neurodevelopmental impairments in order to target early intervention to those in most need. The General Movements Assessment (GMA) in early infancy has high predictive validity for neurodevelopmental outcomes in preterm infants. However, access to a GMA may be limited by geographical constraints and a lack of GMA-trained health professionals. Baby Moves is a smartphone application (app) developed for caregivers to video and upload their infant's general movements to be scored remotely by a certified GMA assessor. The aim of this study is to determine the predictive ability of using the GMA via the Baby Moves app for neurodevelopmental impairment in infants born EP/ELBW.

Methods and analysis

This prospective cohort study will recruit infants born EP/ELBW across the state of Victoria, Australia in 2016 and 2017. A control group of normal birth weight (>2500 g birth weight), term-born (≥37 weeks' gestation) infants will also be recruited as a local reference group. Parents will video their infant's general movements at two time points between 3 and 4 months' corrected age using the Baby Moves app. Videos will be scored by certified GMA assessors and classified as normal or abnormal. Parental satisfaction using the Baby Moves app will be assessed via survey. Neurodevelopmental outcome at 2 years' corrected age includes developmental delay according to the Bayley Scales of Infant and Toddler Development-III and cerebral palsy diagnosis.

Ethics and dissemination

This study was approved by the Human Research and Ethics Committees at the Royal Children's Hospital, The Royal Women's Hospital, Monash Health and Mercy Health in Melbourne, Australia. Study findings will be disseminated via peer-reviewed publications and conference presentations.
Prevalence of Shiga toxin-producing and enteropathogenicEscherichia colimarker genes in diarrhoeic stools in a New Zealand catchment area
Authors: Thomas Rowan R , Brooks Heather J L , O'Brien Rory
Published: October 2016

Background

Shiga toxin-producing (STEC) and enteropathogenic (EPEC)Escherichia coliare gastrointestinal pathogens causing diarrhoeal and extraintestinal disease. Due to lack of EPEC screening and use of Sorbitol-MacConkey (SMAC) agar in faecal screening, the true prevalence of EPEC and non-O157 STEC in New Zealand diarrhoeal cases is unknown.

Methods

Diarrhoeic stools sourced from Dunedin hospital were pre-enriched, DNA extracted with Chelex-100 resin and screened using a multiplex TaqMan quantitative PCR assay amplifyingstx1,sxt2and EPEC (eae) gene markers.

Results

Of the 522 diarrhoeic samples surveyed, 8 (1.53%) were PCR positive forstx1/stx2and 23 (4.41%) were positive foreae. Six (75%) of thestx+samples were uncommon non-O157 serotypes, and the remainder were found to be positive for both O103 and O157 STEC somatic antigens.

Conclusions

Results revealed shortcomings in current screening protocols for pathogenicE. coli; SMAC is not sufficiently discriminatory to detect emergent STEC serotypes and EPEC likely has an unappreciated role in cases of diarrhoea in New Zealand.
Associations with resident physicians’ early adoption of electronic cigarettes for smoking cessation
Authors: Egnot Eric , Jordan Kim , Elliott John O
Published: October 2016

Background

Use of the electronic cigarette for nicotine delivery has increased dramatically in recent years. Information continues to emerge on its role as a smoking cessation aid, but little is known about resident physician use of the device in clinical practice.

Methods

In 2015, an electronic survey was administered to resident physicians in one healthcare system in Columbus, Ohio. The survey included questions about personal smoking exposure, knowledge, beliefs, attitudes about electronic cigarettes and early adoption of electronic cigarettes with patients. Data were dichotomised based on a ‘stages of change’ model that assessed resident physician adoption of electronic cigarettes for therapeutic use. Data were analysed through χ2 tests and logistic regression using ORs and 95% CIs.

Results

Of 338 residents, 142 (42%) responded. Of all residents, 25 (17.7%) reported that they have been recommending electronic cigarettes to their patients for the past 6 months or longer. In the multivariate model, residents ≥postgraduate year (PGY)-3 (OR=3.68, 95% CI 1.20 to 11.29), peer-reviewed article exposure (OR=6.65, 95% CI 1.56 to 28.38) and the view that addictive potential is definitely or somewhat less than traditional cigarettes (OR=5.05, 95% CI 1.48 to 17.24) were associated with recommendation of electronic cigarettes.

Conclusions

Few residents report recommending electronic cigarettes to patients who smoke. These residents consider the electronic cigarette less addicting than traditional cigarettes, supporting harm reduction strategies over strict abstinence. Most residents require further evidence-based education on efficacy and long-term safety of electronic cigarettes before recommending to their patients.
Dynamical behaviors of a general humoral immunity viral infection model with distributed invasion and production
Authors: Ełaiw A. M. , AlShamrani N. H. , Hattaf K.
Published: October 2016

A general nonlinear mathematical model for the viral infection with humoral immunity and two distributed delays is proposed and analyzed. Two bifurcation parameters, the basic reproduction number, [Formula: see text] and the humoral immunity number, [Formula: see text] are derived. We established a set of conditions on the general functions which are sufficient to determine the global dynamics of the model. Utilizing Lyapunov functions and LaSalle’s invariance principle, the global asymptotic stability of all equilibria of the model is obtained. An example is presented and some numerical simulations are conducted in order to illustrate the dynamical behavior.
TiNb2O7 nanorods as a novel anode material for secondary lithium-ion batteries
Authors: Hu Lei , Lin Chunfu , Wang Changhao , Yang Chao , Li Jianbao , Chen Yongjun , Lin Shiwei
Published: October 2016

TiNb2O7 nanorods have been successfully fabricated by a sol–gel method with a sodium dodecyl surfate (SDS) surfactant. X-ray diffraction indicates that the TiNb2O7 nanorods have a Ti2Nb[Formula: see text]O[Formula: see text]-type crystal structure. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results show that the nanorods have an average diameter of [Formula: see text][Formula: see text]100[Formula: see text]nm and an average length of [Formula: see text][Formula: see text]300[Formula: see text]nm. As a result of such nanosizing effect, this new material exhibits advanced electrochemical performances in terms of specific capacity, rate capability and cyclic stability. At 0.1[Formula: see text]C, it delivers a large first-cycle discharge/charge capacity of 337/279 mAh g[Formula: see text]. Its capacities remain 248, 233, 214, 182, 154 and 122[Formula: see text]mAh g[Formula: see text] at 0.5, 1, 2, 5, 10 and 20[Formula: see text]C, respectively. After 100 cycles, its capacity at 10[Formula: see text]C remains 140[Formula: see text]mAh g[Formula: see text] with large capacity retention of 91.0%.
Novel ruptured Sm2O3–In2O3 porous nanotubes with excellent formaldehyde sensing properties
Authors: Wang Xuesong , Wang Guoguang , Guo Xin , Wang Lianyuan , Liu Li , Li Yu , Wang Han
Published: October 2016

Ruptured Sm2O3–In2O3 nanotubes with pores on surface have been successfully synthesized via a single-capillary electrospinning process. The cracks and pores distributed on the nanotube surfaces which can be seen in SEM images facilitate gas transport in materials and increase effective contact areas between gas molecules and materials. Gas sensors based on Sm2O3–In2O3 have been fabricated and investigated for formaldehyde detection. The response to 100[Formula: see text]ppm formaldehyde at the optimum operating temperature of 240[Formula: see text]C is 66.82.
Assessing the Relationship between Sources of Stress and Symptom Changes among Persons with IBD over Time: A Prospective Study
Authors: Bernstein Matthew T. , Targownik Laura E. , Sexton Kathryn A. , Graff Lesley A. , Miller Norine , Walker John R.
Published: October 2016

Objective. To describe the sources of stress for persons with IBD and changes with changes in symptoms.Methods. 487 participants were recruited from a population-based IBD registry. Stress was measured at study entry and three months later, using a general stress measure and the Sources of Stress Scale. Four symptom pattern groups were identified: persistently inactive, persistently active, inactive to active, and active to inactive.Results. General stress levels were stable within each symptom pattern group over the three-month period, even for those with changing symptom activity. The persistently active group had higher general stress at month 0 and month 3 than the persistently inactive group and higher mean ratings of most sources of stress. IBD was rated as a highly frequent source of stress by 20–30% of the persistently active group compared to 1-2% of the inactive group. Finances, work, and family were rated as high frequency stresses in the persistently active group at a similar level to IBD stress. In the groups with fluctuating symptoms, there was little change in stress ratings with changes in symptom activity.Conclusion. Stress was experienced across several domains in addition to stress related to IBD. Persons with active symptoms may benefit from targeted stress interventions.
Lipoma of Piriform Sinus: A Case Report and Review of the Literature
Authors: Acquaviva Gilberto , Varakliotis Theodoros , Badia Stefano , Casorati Francesco , Eibenstein Alberto , Bellocchi Gianluca
Published: October 2016

The lipomas of oropharynx, hypopharynx, and larynx are so rare that up to now approximately there have been 100 cases reported. The lipomas are slow-growing lesions that are capable of reaching considerable dimensions and are often detected at a late stage. The symptoms can vary both in dimension and in location, semiobstructing the aerodigestive tract or exerting compression on adjacent structure. In this case, the lesion, which originated from the piriform sinus, was removed endoscopically urgently due to obvious signs of tissue suffering caused by stretching of the pedicle as a result of displacement of the mass. The two aims of this case report are to expose an interesting and rare case study mainly for an Emergency Room Specialist and an ENT (Ear, Nose, and Throat) Specialist involved in solving the problem and to demonstrate that the choice of an endoscopic approach is useful in order to have an optimal visualization of the lesion and to perform a total eradication. The use of endoscopic devices also allows a rapid postoperative recovery, compared to external access and optimum locoregional control in the follow-up procedures to prevent possible relapses.
Resistance of Permafrost and ModernAcinetobacter lwoffiiStrains to Heavy Metals and Arsenic Revealed by Genome Analysis
Authors: Mindlin Sofia , Petrenko Anatolii , Kurakov Anton , Beletsky Alexey , Mardanov Andrey , Petrova Mayya
Published: October 2016

We performed whole-genome sequencing of five permafrost strains ofAcinetobacter lwoffii(frozen for 15–3000 thousand years) and analyzed their resistance genes found in plasmids and chromosomes. Four strains contained multiple plasmids (8–12), which varied significantly in size (from 4,135 to 287,630 bp) and genetic structure; the fifth strain contained only two plasmids. All large plasmids and some medium-size and small plasmids contained genes encoding resistance to various heavy metals, including mercury, cobalt, zinc, cadmium, copper, chromium, and arsenic compounds. Most resistance genes found in the ancient strains ofA.lwoffiihad their closely related counterparts in modern clinicalA.lwoffiistrains that were also located on plasmids. The vast majority of the chromosomal resistance determinants did not possess complete sets of the resistance genes or contained truncated genes. Comparative analysis of variousA.lwoffiiand ofA.baumanniistrains discovered a number of differences between them: (i) chromosome sizes inA.baumanniiexceeded those inA.lwoffiiby about 20%; (ii) on the contrary, the number of plasmids inA.lwoffiiand their total size were much higher than those inA.baumannii; (iii) heavy metal resistance genes in the environmentalA.lwoffiistrains surpassed those inA.baumanniistrains in the number and diversity and were predominantly located on plasmids. Possible reasons for these differences are discussed.
Is the Presence of the Father of the Baby during First Prenatal Ultrasound Study Visit Associated with Improved Pregnancy Outcomes in Adolescents and Young Adults?
Authors: Lee Sara H. , Lazebnik Rina , Kuper-Sassé Margaret , Lazebnik Noam
Published: October 2016

This study examined whether the presence of the father of the baby (FOB) at the first prenatal ultrasound study (US) visit of pregnant adolescents and young adults (AYA) is a marker for improved pregnancy outcomes. Charts of 400 pregnant AYA aged 14–22 years seen at an academic maternity hospital were assessed retrospectively for support persons brought to prenatal US visits. Logistic regression analysis was used to examine the association between FOB presence and gestational age and birth weight. Of 400 charts with support person recorded, 298 charts with first US visit data, singleton birth, and complete gestational data available were analyzed. FOB was present at 30.2% of visits, while the parent of the mother was present at 34.2% of visits. With FOB present, 3.3% of infants were born preterm (gestational age < 37 weeks) compared with 10.5% of infants with FOB absent (p=0.04). Patients with FOB present also had significantly earlier gestational age at the first US visit (15 weeks) than those who did not (19 weeks;p=0.02). For AYA, the presence of FOB at initial prenatal US visits is a predictor of improved pregnancy outcome and likely represents increased support during the pregnancy.