bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement of silicon waveguide transmission by advanced e-beam lithography data fracturing strategies
Authors: Patrick Shane , Bojko Richard J. , Stammberger Stefan J. H. , Luan Enxiao , Chrostowski Lukas
Published: October 2017

In the maturing field of silicon photonics, advances continue in both design and process improvements. Waveguide propagation loss is strongly affected by sidewall roughness, and so for fabrication using e-beam lithography, loss is influenced by e-beam writing parameters. Here, the authors look specifically at fracturing strategies in data preparation for e-beam lithography, and find significant reduction in waveguide loss by utilizing advanced fracturing options. For our evaluation, the authors fabricate optical waveguides using a well-characterized, highly stable baseline fabrication process with hydrogen silsesquioxane resist exposed by a 100 kV electron beam, a high-contrast tetramethyl-ammonium hydroxide develop, and a Cl2 inductively coupled plasma etch. Using surface grating couplers for input and output, automated optical measurements are made by scanning input light in the region of the design wavelength of 1550 nm and measuring optical output power. The authors use a design cell containing grating couplers and both straight and curved waveguides with a range of lengths. The authors find a significant reduction in grating coupler insertion loss and waveguide loss along with increased uniformity by leveraging a new fracturing strategy implemented in the beamer pattern data processing software from GenISys, GmbH. Single line edge smoothing is an exposure strategy in which all feature edges are traced using a single-line shape (sometimes referred to as a single-pass line) while the bulk of the shape is then exposed with trapezoidal beam filling. The insertion loss for grating couplers written using single line edge smoothing shows a significant loss reduction of 1.2 dB as well as greatly improved uniformity. Both straight and curved waveguide losses were also reduced by use of single line edge smoothing, by 0.7 and 1.1 dB/cm, respectively. Here, the authors will discuss the likely mechanisms of this improvement as well as present additional device data using these new fracturing methods which represent a significant, incremental improvement in performance of optical waveguides written by e-beam lithography.
Fifty nanometer lines patterned into silica using water developable chitosan bioresist and electron beam lithography
Authors: Caillau Mathieu , Crémillieu Pierre , Laurenceau Emmanuelle , Chevolot Yann , Leclercq Jean-Louis , Alekseev Sergeï , Chevalier Céline , Delair Thierry
Published: October 2017

Current chemicals used in electron beam (e-beam) lithography generate safety and waste management issues. To replace them, chitosan, a natural and abundant polymer soluble in water based solutions, was assessed as a positive and water developable resist for a two-layer e-beam lithography and as a mask for transfer by etching in silica. Fifty nanometer line patterns were successfully obtained in a chitosan film by e-beam lithography at doses between 160 and 300 μC cm−2, then, transferred into a silica layer by CHF3 plasma reactive ion etching with respect of the feature dimensions.
Atomic layer deposition of Ti-Nb-O thin films onto electrospun fibers for fibrous and tubular catalyst support structures
Authors: Putkonen Matti , Heikkilä Pirjo , Pasanen Antti T. , Rautkoski Hille , Svärd Laura , Simell Pekka , Vähä-Nissi Mika , Sajavaara Timo
Published: October 2017

Here, the authors report on the preparation of core–shell carbon-ceramic fibrous as well as ceramic tubular catalyst supports utilizing electrospinning and atomic layer deposition (ALD). In this paper, ALD of Ti-Nb-O thin films using TiCl4, Nb(OEt)5, and H2O as precursors is demonstrated. According to the time-of-flight-elastic recoil detection analysis and Rutherford backscattering spectrometry, carbon and hydrogen impurities were relatively low, but depend on the pulsing ratio of the precursors. Optimized ALD process was used for coating of sacrificial electrospun polyvinyl alcohol (PVA) template fibers to yield tubular Ti-Nb-O structures after thermal or solution based PVA removal. Another approach utilized 200–400 nm thick carbon fibers prepared by electrospinning from polyacrylonitrile and subsequent thermal treatment.
Acoustic factors affecting the dynamic range of a choir
Authors: Titze Ingo R. , Maxfield Lynn
Published: October 2017

Based on the assumption that individual sound intensities of singers are incoherent and add linearly to produce a combined choir intensity, a model of a voice range profile of a choir is produced. It is shown that this model predicts six distinct levels of choir dynamics (pp p mp mf f ff) over two octaves of fundamental frequency in a choir section. The levels are 3–6 dB apart, depending on the individual voice range profiles of the singers. Overall choir size has no effect on dynamic range, unless the size is varied dynamically by not all singers singing all the time. For a non-homogeneousn group of singers, a few loud voices dominate ff if everyone sings, while pp is not achieved effectively without suppressing all voices that cannot sing soft. Furthermore, the dynamic range can be significantly limited when choral blend for loudness is imposed on a non-homogeneous choir.
In Vitro
Human Onychopharmacokinetic and Pharmacodynamic Analyses of ME1111, a New Topical Agent for Onychomycosis
Authors: Kubota-Ishida Natsuki , Takei-Masuda Naomi , Kaneda Kaori , Nagira Yu , Chikada Tsubasa , Nomoto Masahiro , Tabata Yuji , Takahata Sho , Maebashi Kazunori , Hui Xiaoying , Maibach Howard I.
Published: October 2017

ME1111 is a novel antifungal agent currently under clinical development as a topical onychomycosis treatment. A major challenge in the application of topical onychomycotics is penetration and dissemination of antifungal agent into the infected nail plate and bed. In this study, pharmacokinetic/pharmacodynamic parameters of ME1111 that potentially correlate with clinical efficacy were compared with those of marketed topical onychomycosis antifungal agents: efinaconazole, tavaborole, ciclopirox, and amorolfine. An ME1111 solution and other launched topical formulations were applied to an
in vitro
dose model for 14 days based on their clinical dose and administration. Drug concentrations in the deep layer of the nail and within the cotton pads beneath the nails were measured using liquid chromatography-tandem mass spectrometry. Concentrations of ME1111 in the nail and cotton pads were much higher than those of efinaconazole, ciclopirox, and amorolfine. Free drug concentrations of ME1111 in deep nail layers and cotton pads were orders of magnitude higher than the MIC
90
value against
Trichophyton rubrum
(
n
= 30). Unlike other drugs, the
in vitro
antifungal activity of ME1111 was not affected by 5% human keratin and under a mild acidic condition (pH 5.0). The
in vitro
antidermatophytic efficacy coefficients (ratio of free drug concentration to MIC
90
s against
T. rubrum
) of ME1111, as measured in deep nail layers, were significantly higher than those of efinaconazole, tavaborole, ciclopirox, and amorolfine (
P
< 0.05). This suggests that ME1111 has excellent permeation of human nails and, consequently, the potential to be an effective topical onychomycosis treatment.
Chitinase Induction Prior to Caspofungin Treatment of Experimental Invasive Aspergillosis in Neutropenic Rats Does Not Enhance Survival
Authors: Refos Jeannine M. , Vonk Alieke G. , ten Kate Marian T. , Verbrugh Henri A. , Bakker-Woudenberg Irma A. J. M. , van de Sande Wendy W. J.
Published: October 2017

Host chitinases, chitotriosidase and acidic mammalian chitinase (AMCase), improved the antifungal activity of caspofungin (CAS) against
Aspergillus fumigatus in vitro
. These chitinases are not constitutively expressed in the lung. Here, we investigated whether chitosan derivatives were able to induce chitinase activity in the lungs of neutropenic rats and, if so, whether these chitinases were able to prolong survival of rats with invasive pulmonary aspergillosis (IPA) or of rats with IPA and treated with CAS. An oligosaccharide-lactate chitosan (OLC) derivative was instilled in the left lung of neutropenic rats to induce chitotriosidase and AMCase activities. Rats instilled with OLC or with phosphate-buffered saline (PBS) were subsequently infected with
A. fumigatus
and then treated with suboptimal doses of CAS. Survival, histopathology, and galactomannan indexes were determined. Instillation of OLC resulted in chitotriosidase and AMCase activities. However, instillation of OLC did not prolong rat survival when rats were subsequently challenged with
A. fumigatus
. In 5 of 7 rats instilled with OLC, the fungal foci in the lungs were smaller than those in rats instilled with PBS. Instillation of OLC did not significantly enhance the survival of neutropenic rats challenged with
A. fumigatus
and treated with a suboptimal dosage of CAS. Chitotriosidase and AMCase activities can be induced with OLC, but the presence of active chitinases in the lung did not prevent the development of IPA or significantly enhance the therapeutic outcome of CAS treatment.
Mutations at the Ribosomal S10 Gene in Clinical Strains of Staphylococcus aureus with Reduced Susceptibility to Tigecycline
Authors: Argudín M. Angeles , Roisin S. , Dodémont M. , Nonhoff C. , Deplano A. , Denis O.
Published: October 2017

Mutations on the tip of the extended loop of the ribosomal S10 protein have been associated to tigecycline (TGC) resistance in passaged mutants of different bacteria species. This study described the first two clinical TGC-resistant
Staphylococcus aureus
isolates with these mutations. One strain (TGC MIC = 2 mg/liter) had a 12-nucleotide deletion affecting residues 56 to 59 (HKYK) of the S10 protein. The second strain (TGC MIC = 1 mg/liter) had amino acid substitutions (K57M and Y58F) previously described in
S. aureus
passaged mutants.
Antifungal Susceptibility of Emerging Dimorphic Pathogens in the Family Ajellomycetaceae
Authors: Dukik Karolina , Al-Hatmi Abdullah M. S. , Curfs-Breuker Ilse , Faro Dirk , de Hoog Sybren , Meis Jacques F.
Published: October 2017

The
in vitro
susceptibilities of 24 molecularly identified dimorphic fungi belonging to the genera
Adiaspiromyces
,
Blastomyces
, and
Emergomyces
within the family
Ajellomycetaceae
were tested against 8 standard antifungal agents using CLSI document M38-A2. Amphotericin B and posaconazole had the lowest geometric mean MICs (<0.05 μg/ml) followed by itraconazole (<0.07 μg/ml), voriconazole (<0.15 μg/ml), and isavuconazole (<0.42 μg/ml) while fluconazole was not active. Micafungin demonstrated good
in vitro
antifungal activity against
Emergomyces
(geometric mean minimum effective concentration [GM MEC] 0.1 μg/ml) and
Blastomyces
(GM MEC <0.017 μg/ml).
In Vitro
Activity of Meropenem-Vaborbactam against Clinical Isolates of KPC-Positive Enterobacteriaceae
Authors: Hackel Meredith A. , Lomovskaya Olga , Dudley Michael N. , Karlowsky James A. , Sahm Daniel F.
Published: October 2017

Vaborbactam (formerly RPX7009) is a novel inhibitor of serine β-lactamases, including Ambler class A carbapenemases, such as KPCs. The current study evaluated the
in vitro
activity of the combination agent meropenem-vaborbactam against a global collection of 991 isolates of KPC-positive
Enterobacteriaceae
collected in 2014 and 2015 using the Clinical and Laboratory Standards Institute (CLSI) standard broth microdilution method. The MIC
90
of meropenem (when tested with a fixed concentration of 8 μg/ml of vaborbactam) for isolates of KPC-positive
Enterobacteriaceae
was 1 μg/ml, and MIC values ranged from ≤0.03 to >32 μg/ml; 99.0% (981/991) of isolates had meropenem-vaborbactam MICs of ≤4 μg/ml, the U.S. FDA-approved MIC breakpoint for susceptibility to meropenem-vaborbactam (Vabomere). Vaborbactam lowered the meropenem MIC
50
from 32 to 0.06 μg/ml and the MIC
90
from >32 to 1 μg/ml. There were no differences in the activity of meropenem-vaborbactam when the isolates were stratified by KPC variant type. We conclude that meropenem-vaborbactam demonstrates potent
in vitro
activity against a worldwide collection of clinical isolates of KPC-positive
Enterobacteriaceae
collected in 2014 and 2015.
Molecular Pathogenesis of Chlamydia Disease Complications: Epithelial-Mesenchymal Transition and Fibrosis
Authors: Igietseme Joseph U. , Omosun Yusuf , Nagy Tamas , Stuchlik Olga , Reed Matthew S. , He Qing , Partin James , Joseph Kahaliah , Ellerson Debra , George Zenas , Goldstein Jason , Eko Francis O. , Bandea Claudiu , Pohl Jan , Black Carolyn M.
Published: October 2017

The reproductive system complications of genital chlamydial infection include fallopian tube fibrosis and tubal factor infertility. However, the molecular pathogenesis of these complications remains poorly understood. The induction of pathogenic epithelial-mesenchymal transition (EMT) through microRNA (miRNA) dysregulation was recently proposed as the pathogenic basis of chlamydial complications. Focusing on fibrogenesis, we investigated the hypothesis that chlamydia-induced fibrosis is caused by EMT-driven generation of myofibroblasts, the effector cells of fibrosis that produce excessive extracellular matrix (ECM) proteins. The results revealed that the targets of a major category of altered miRNAs during chlamydial infection are key components of the pathophysiological process of fibrogenesis; these target molecules include collagen types I, III, and IV, transforming growth factor β (TGF-β), TGF-β receptor 1 (TGF-βR1), connective tissue growth factor (CTGF), E-cadherin, SRY-box 7 (SOX7), and NFAT (nuclear factor of activated T cells) kinase dual-specificity tyrosine (Y) phosphorylation-regulated kinase 1a (Dyrk1a). Chlamydial induction of EMT resulted in the generation of α-smooth muscle actin (α-SMA)-positive myofibroblasts that produced ECM proteins, including collagen types I and III and fibronectin. Furthermore, the inhibition of EMT prevented the generation of myofibroblasts and production of ECM proteins during chlamydial infection. These findings may provide useful avenues for targeting EMT or specific components of the EMT pathways as a therapeutic intervention strategy to prevent chlamydia-related complications.
What Is a Host? Attributes of Individual Susceptibility
Authors: Casadevall Arturo , Pirofski Liise-anne
Published: October 2017

In every epidemic some individuals become sick and some may die, whereas others recover from illness and still others show no signs or symptoms of disease. These differences highlight a fundamental question of microbial pathogenesis: why are some individuals susceptible to infectious diseases while others who acquire the same microbe remain well? For most of human history, the answer assumed the hand of providence. With the advent of the germ theory of disease, the focus on disease causality became the microbe, but this did not explain how there can be different outcomes of infection in different individuals with the same microbe. Here we examine the attributes of susceptibility in the context of the “damage-response framework” of microbial pathogenesis. We identify 11 attributes that, although not independent, are sufficiently distinct to be considered separately: microbiome, inoculum, sex, temperature, environment, age, chance, history, immunity, nutrition, and genetics. We use the first letter of each to create the mnemonic MISTEACHING, underscoring the need for caution in accepting dogma and attributing disease causality to any single factor. For both populations and individuals, variations in the attributes that assemble into MISTEACHING can create an enormity of combinations that can in turn translate into different outcomes of host-microbe encounters. Combinatorial diversity among the 11 attributes makes identifying “signatures” of susceptibility possible. However, with their inevitable uncertainties and propensity to change, there may still be a low likelihood for prediction with regard to individual host-microbe interactions, although probabilistic prediction may be possible.
Identification of Parameters of Host Cell Vulnerability during Salmonella Infection by Quantitative Image Analysis and Modeling
Authors: Voznica Jakub , Gardella Christophe , Belotserkovsky Ilia , Dufour Alexandre , Enninga Jost , Stévenin Virginie
Published: October 2017

Salmonella
targets and enters epithelial cells at permissive entry sites: some cells are more likely to be infected than others. However, the parameters that lead to host cell heterogeneity are not known. Here, we quantitatively characterized host cell vulnerability to
Salmonella
infection based on imaged parameters. We performed successive infections of the same host cell population followed by automated high-throughput microscopy and observed that infected cells have a higher probability of being reinfected. Establishing a predictive model, we identified two combined origins of host cell vulnerability: pathogen-induced cellular vulnerability emerging from
Salmonella
uptake and persisting at later stages of the infection and host cell-inherent vulnerability. We linked the host cell-inherent vulnerability with its morphological attributes, such as local cell crowding, and with host cell cholesterol content. This showed that the probability of
Salmonella
infection success can be forecast from morphological or molecular host cell parameters.
Visualizing Bacterial Colony Morphologies Using Time-Lapse Imaging Chamber MOCHA
Authors: Peñil Cobo Maria , Libro Silvia , Marechal Nils , D'Entremont David , Peñil Cobo David , Berkmen Mehmet
Published: October 2017

Capturing microbial growth on a macroscopic scale is of great importance to further our understanding of microbial life. However, methods for imaging microbial life on a scale of millimeters to centimeters are often limited by designs that have poor environmental control, resulting in dehydration of the agar plate within just a few days. Here, we created MOCHA (
m
icr
o
bial
cha
mber), a simple but effective chamber that allows users to study microbial growth for extended periods (weeks) in a stable environment. Agar hydration is maintained with a double-decker design, in which two glass petri dishes are connected by a wick, allowing the lower plate to keep the upper plate hydrated. This flexible chamber allows the observation of a variety of microbiological phenomena, such as the growth and development of single bacterial and fungal colonies, interspecies interactions, swarming motility, and pellicle formation.

IMPORTANCE
Detailed study of microbial life on the colony scale of millimeters to centimeters has been lagging considerably behind microscopic inspection of microbes. One major reason for this is the lack of inexpensive instrumentation that can reproducibly capture images in a controlled environment. In this study, we present the design and use of a unique chamber that was used to produce several time-lapse movies that aimed to capture the diversity of microbial colony phenotypes over long periods.
New Kid on the Block: LmbU Expands the Repertoire of Specialized Metabolic Regulators in Streptomyces
Authors: Ju Kou-San , Zhang Xiafei , Elliot Marie A.
Published: October 2017

Streptomyceshas an extensive natural product repertoire, including most of the naturally derived antibiotics. Understanding the control of natural product biosynthesis is central to antibiotic discovery and production optimization. Here, Hou et al. (J. Bacteriol. 200:00447-17, 2018,https://doi.org/10.1128/JB.00447-17) report the identification and characterization of a novel regulator—LmbU—that functions primarily as an activator of lincomycin production inStreptomyces lincolnensis. Importantly, members of this new regulator family are associated with natural product biosynthetic clusters throughout the streptomycetes and their actinomycete relatives.
Clinical implications from daily physiotherapy examination of 131 acute hamstring injuries and their association with running speed and rehabilitation progression
Authors: Whiteley Rod , van Dyk Nicol , Wangensteen Arnlaug , Hansen Clint
Published: October 2017

Aim

To investigate the association of daily clinical measures and the progression of rehabilitation and perceived running effort.

Methods

A cohort of 131 athletes with an MRI-confirmed acute hamstring injury underwent a standardised criteria-based rehabilitation protocol. Descriptive and inferential statistics were used to investigate the association between daily clinical subjective and objective measures and both the progression of rehabilitation and perceived running effort. These measures included different strength, palpation, flexibility and functional tests. Inter-rater and intrarater reliability and minimal detectable change were established for the clinical measures of strength and flexibility by examining measures taken on consecutive days for the uninjured leg.

Results

The progression of the daily measures was seen to be non-linear and varied according to the measure. Intra-rater reliability for the strength and flexibility measures were excellent (95% CI ≥0.85 for all measures). Strength (in the outer range position) and flexibility (in maximum hip flexion with active knee extension (MHFAKE) in supine) were best associated with rehabilitation progression and perceived running effort. Additionally, length of pain on palpation was usefully associated with rehabilitation progression. At lower perceived running effort there was a large variation in actual running speed.

Conclusion

Daily physical measures of palpation pain, outer range strength, MHFAKE and reported pain during daily activity are useful to inform the progression of rehabilitation.

Trial registration number

NCT01812564 andNCT02104258.
Crash-test dummy and pendulum impact tests of ice hockey boards: greater displacement does not reduce impact
Authors: Schmitt Kai-Uwe , Muser Markus H , Thueler Hansjuerg , Bruegger Othmar
Published: October 2017

Background

One injury mechanism in ice hockey is impact with the boards. We investigated whether more flexible hockey boards would provide less biomechanical loading on impact than did existing (reference) boards.

Methods

We conducted impact tests with a dynamic pendulum (mass 60 kg) and with crash test dummies (ES-2 dummy, 4.76 m/s impact speed). Outcomes were biomechanical loading experienced by a player in terms of head acceleration, impact force to the shoulder, spine, abdomen and pelvis as well as compression of the thorax.

Results

The more flexible board designs featured substantial displacement at impact. Some so-called flexible boards were displaced four times more than the reference board. The new boards possessed less stiffness and up to 90 kg less effective mass, reducing the portion of the board mass a player experienced on impact, compared with boards with a conventional design. Flexible boards resulted in a similar or reduced loading for all body regions, apart from the shoulder. The displacement of a board system did not correlate directly with the biomechanical loading.

Conclusions

Flexible board systems can reduce the loading of a player on impact. However, we found no correlation between the displacement and the biomechanical loading; accordingly, displacement alone was insufficient to characterise the overall loading of a player and thus the risk of injury associated with board impact. Ideally, the performance of boards is assessed on the basis of parameters that show a good correlation to injury risk.
Association between self-reported sleep duration and serum lipid profile in a middle-aged and elderly population in Taiwan: a community-based, cross-sectional study
Authors: Lin Pu , Chang Kai-Ting , Lin Yan-An , Tzeng I-Shiang , Chuang Hai-Hua , Chen Jau-Yuan
Published: October 2017

Objectives

The association between sleep duration and serum lipid profile in the middle-aged and the elderly is unclear. The aim of this study was to investigate and evaluate the relationships between sleep duration and levels of serum total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C) and triglycerides in these populations.

Design

Cross-sectional observational study.

Setting

Community-based investigation in Guishan Township of northern Taiwan.

Participants

A total of 400 community-dwelling middle-aged and elderly individuals were enrolled. All participants underwent a baseline assessment in 2014, which included anthropometrics, blood samples and self-administered questionnaires. Participants were classified into three groups based on their sleep duration.

Outcome measures

Multivariate logistic regression was used to obtain ORs and 95% CIs to assess the relationship between sleep duration and lipid profiles.

Results

Participant mean age was 64.5 years and 35.3% were men. Subjects with longer (>7 hours) and shorter (<6 hours) nightly sleep duration had a higher prevalence of low HDL-C levels (HDL <40 mg/dL) than those with moderate sleep duration (6–7 hours). Multivariate logistic regression revealed that, compared with individuals with sleep duration of 6–7 hours, the ORs of having low HDL-C were 3.68 (95% CI 1.59 to 8.49) greater for individuals with sleep duration of <6 hours and 2.89 (95% CI 1.10 to 7.61) greater for individuals with sleep duration of >7 hours.

Conclusions

There was a U-shaped relationship between sleep duration and HDL-C levels. Sleep duration >7 hours or <6 hours increased the risk of low serum HDL-C levels.
Targeted Adherence Intervention to Reach Glycemic Control with Insulin Therapy for patients with Diabetes (TARGIT-Diabetes): rationale and design of a pragmatic randomised clinical trial
Authors: Lewey Jennifer , Wei Wenhui , Lauffenburger Julie C , Makanji Sagar , Chant Alan , DiGeronimo Jeff , Nanchanatt Gina , Jan Saira , Choudhry Niteesh K
Published: October 2017

Introduction

Adherence to and persistence of medications for chronic diseases remains poor and many interventions to improve medication use have only been modestly effective. Targeting interventions to patients who are most likely to benefit should improve their efficiency and clinical impact. This study aims to test the impact of three cost-equivalent pharmacist-led interventions on insulin persistence and glycaemic control among patients with diabetes.

Methods and analysis

TARGIT-Diabetes (Targeted Adherence Intervention to Reach Glycemic Control with Insulin Therapy for patients with Diabetes) is a randomised controlled trial that will evaluate three different multifaceted pharmacist-outreach strategies for improving long-term insulin use among individuals with diabetes. We will randomise 6000 patients in a large insurer to one of three arms. The arms are designed to deliver an increasingly intensive intervention to a progressively targeted population, identified using predictive analytics. The central component of the intervention in all arms is a tailored telephone consultation with a pharmacist which varies across arms based on the: (A) proportion of patients offered the intervention and (B) intervention intensity, including follow-up frequency and cointerventions such as text reminders and interactions with patients’ providers. The primary outcome is insulin persistence, assessed using pharmacy claims data, and the secondary outcomes are glycaemic control as measured by glycosylated haemoglobin values, healthcare utilisation and healthcare spending.

Ethics and dissemination

This protocol has been approved by the Institutional Review Board of Brigham and Women’s Hospital and the Privacy Board of Horizon Blue Cross Blue Shield of New Jersey. We plan to present the results of this trial at national meetings and in manuscripts submitted to peer-reviewed journals.

Trial registration number

NCT 02846779.
Identifying patterns of item missing survey data using latent groups: an observational study
Authors: Barnett Adrian G , McElwee Paul , Nathan Andrea , Burton Nicola W , Turrell Gavin
Published: October 2017

Objectives

To examine whether respondents to a survey of health and physical activity and potential determinants could be grouped according to the questions they missed, known as ‘item missing’.

Design

Observational study of longitudinal data.

Setting

Residents of Brisbane, Australia.

Participants

6901 people aged 40–65 years in 2007.

Materials and methods

We used a latent class model with a mixture of multinomial distributions and chose the number of classes using the Bayesian information criterion. We used logistic regression to examine if participants’ characteristics were associated with their modal latent class. We used logistic regression to examine whether the amount of item missing in a survey predicted wave missing in the following survey.

Results

Four per cent of participants missed almost one-fifth of the questions, and this group missed more questions in the middle of the survey. Eighty-three per cent of participants completed almost every question, but had a relatively high missing probability for a question on sleep time, a question which had an inconsistent presentation compared with the rest of the survey. Participants who completed almost every question were generally younger and more educated. Participants who completed more questions were less likely to miss the next longitudinal wave.

Conclusions

Examining patterns in item missing data has improved our understanding of how missing data were generated and has informed future survey design to help reduce missing data.
Maintenance therapy with proton pump inhibitors and risk of gastric cancer: a nationwide population-based cohort study in Sweden
Authors: Brusselaers Nele , Wahlin Karl , Engstrand Lars , Lagergren Jesper
Published: October 2017

Objective

Proton pump inhibitors (PPIs) are among the most commonly prescribed drugs. Concerns have been raised about a potentially increased risk of gastric cancer following long-term use. Our aim is to assess the risk of gastric cancer associated with PPI use, taking into account underlying indications.

Design

This is a population-based cohort study. Standardised incidence ratios (SIRs) and 95% CIs were calculated to compare the risk of gastric cancer among long-term PPI users with the corresponding background population, while taking confounding by indication into account.

Setting

Population-based study in Sweden (2005–2012).

Participants

This study included virtually all adults residing in Sweden exposed to maintenance therapy with PPIs.

Exposure/Intervention

Maintenance use of PPIs, defined as at least 180 days during the study period. Maintenance use of histamine 2 receptor antagonist was evaluated for comparison reasons.

Outcome measures

Gastric cancer (cardia and non-cardia), and subgroup analysis for gastric adenocarcinoma, as defined by the Swedish Cancer Registry.

Results

Among 797 067 individuals on maintenance PPI therapy, the SIR of gastric cancer was over threefold increased (SIR=3.38, 95% CI 3.23 to 3.53). Increased SIRs were found in both sexes and all age groups, but were especially increased among PPI users younger than 40 years (SIR=22.76, 95% CI 15.94 to 31.52). Increased SIRs were found for each indication studied, including those without an association with gastric cancer, for example, gastro-oesophageal reflux (SIR=3.04, 95% CI 2.80 to 3.31), and those with a supposedly decreased risk, for example, aspirin users (SIR=1.93, 95% CI 1.70 to 2.18). The association was similar for cardia and non-cardia gastric cancer. Analyses restricted to adenocarcinoma showed similar results to those for all gastric cancers. Long-term users of histamine 2 receptor antagonists, which have the same indications as PPIs, were not at any increased risk.

Conclusions

Long-term PPI use might be an independent risk factor for gastric cancer. This challenges broad maintenance PPI therapy, particularly if the indication is weak.
Calculating the proportion of avoidable attendances at UK emergency departments: analysis of the Royal College of Emergency Medicine’s Sentinel Site Survey data
Authors: Morris Toby , Mason Suzanne M , Moulton Chris , O’Keeffe Colin
Published: October 2017

Introduction

Avoidable attendances (AAs; defined as non-urgent, self-referred patients who could be managed more effectively and efficiently by other services) have been identified as a contributor to ED crowding. Internationally, AAs have been estimated to constitute 10%–90% of ED attendances, with the UK 2013 Urgent and Emergency Care Review suggesting a figure of 40%.

Methods

This pilot study used data from the Royal College of Emergency Medicine’s Sentinel Site Survey to estimate the proportion of AAs in 12 EDs across England on a standard day (20 March 2014). AAs were defined by an expert panel using questions from the survey. All patients attending the EDs were recorded with details of investigations and treatments received, and the proportion of patients meeting criteria for AA was calculated.

Results

Visits for 3044 patients were included. Based on these criteria, a mean of 19.4% (95% CI 18.0% to 20.8%) of attendances could be deemed avoidable. The lowest proportion of AAs reported was 10.7%, while the highest was 44.3%. Younger age was a significant predictor of AA with mean age of 38.6 years for all patients attending compared with 24.6 years for patients attending avoidably (p≤0.001).

Discussion

The proportion of AAs in this study was lower than many estimates in the literature, including that reported by the 2013 Urgent and Emergency Care Review. This suggests the ED is the most appropriate healthcare setting for many patients due to comprehensive investigations, treatments and capability for urgent referrals.

The proportion of AAs is dependent on the defining criteria used, highlighting the need for a standardised, universal definition of an appropriate/avoidable ED attendance. This is essential to understanding how AAs contribute to the overall issue of crowding.
Methylation panel is a diagnostic biomarker for Barrett’s oesophagus in endoscopic biopsies and non-endoscopic cytology specimens
Authors: Chettouh Hamza , Mowforth Oliver , Galeano-Dalmau Núria , Bezawada Navya , Ross-Innes Caryn , MacRae Shona , Debiram-Beecham Irene , O’Donovan Maria , Fitzgerald Rebecca C
Published: October 2017

Objective

Barrett’s oesophagus is a premalignant condition that occurs in the context of gastro-oesophageal reflux. However, most Barrett’s cases are undiagnosed because of reliance on endoscopy. We have developed a non-endoscopic tool: the Cytosponge, which when combined with trefoil factor 3 immunohistochemistry, can diagnose Barrett’s oesophagus. We investigated whether a quantitative methylation test that is not reliant on histopathological analysis could be used to diagnose Barrett’s oesophagus.

Design

Differentially methylated genes between Barrett’s and normal squamous oesophageal biopsies were identified from whole methylome data and confirmed using MethyLight PCR in biopsy samples of squamous oesophagus, gastric cardia and Barrett’s oesophagus. Selected genes were then tested on Cytosponge BEST2 trial samples comprising a pilot cohort (n=20 cases, n=10 controls) and a validation cohort (n=149 cases, n=129 controls).

Results

Eighteen genes were differentially methylated in patients with Barrett’soesophagus compared with squamous controls. Hypermethylation of TFPI2, TWIST1, ZNF345 and ZNF569 was confirmed in Barrett’s biopsies compared with biopsies from squamous oesophagus and gastric cardia (p<0.05). When tested in Cytosponge samples, these four genes were hypermethylated in patients with Barrett’s oesophagus compared with patients with reflux symptoms (p<0.001). The optimum biomarker to diagnose Barrett’s oesophagus was TFPI2 with a sensitivity and specificity of 82.2% and 95.7%, respectively.

Conclusion

TFPI2, TWIST1, ZNF345 and ZNF569methylation have promise as diagnostic biomarkers for Barrett’s oesophagus when used in combination with a simple and cost effective non-endoscopic cell collection device.
Competence and lithostratigraphy of host rocks govern kimberlite pipe morphology
Authors: Newton David E. , Ryan Amy G. , Hilchie Luke J.
Published: October 2017

We use analogue experimentation to test the hypothesis that host rock competence primarily determines the morphology of kimberlite pipes. Natural occurrences of kimberlite pipes are subdivided into three classes: class 1 pipes are steep-sided diatremes emplaced into crystalline rock; class 2 pipes have a wide, shallow crater emplaced into sedimentary rock overlain by unconsolidated sediments; class 3 pipes comprise a steep-sided diatreme with a shallow-angled crater emplaced into competent crystalline rock overlain by unconsolidated sediments. We use different configurations of three analogue materials with varying cohesions to model the contrasting geological settings observed in nature. Pulses of compressed air, representing the energy of the gas-rich head of a kimberlitic magma, are used to disrupt the experimental substrate. In our experiments, the competence and configuration of the analogue materials control the excavation processes as well as the final shape of the analogue pipes: eruption through competent analogue strata results in steep-sided analogue pipes; eruption through weak analogue strata results in wide, shallow analogue pipes; eruption through intermediate strength analogue strata results in analogue pipes with a shallow crater and a steep-sided diatreme. These experimental results correspond with the shapes of natural kimberlite pipes, and demonstrate that variations in the lithology of the host rock are sufficient to generate classic kimberlite pipe shapes. These findings are consistent with models that ascribe the pipe morphologies of natural kimberlites to the competence of the host rocks in which they are emplaced.
Molecular identification ofNeofabraeaspecies associated with bull’s-eye rot on apple using rolling-circle amplification of partialEF-1αsequence
Authors: Lin Huijiao , Jiang Xiang , Yi Jianping , Wang Xinguo , Zuo Ranling , Jiang Zide , Wang Weifang , Zhou Erxun
Published: October 2017

A rolling-circle amplification (RCA) method with padlock probes targeted on EF-1α regions was developed for rapid detection of apple bull’s-eye rot pathogens, including Neofabraea malicorticis, N. perennans, N. kienholzii, and N. vagabunda (synonym: N. alba). Four padlock probes (PLP-Nm, PLP-Np, PLP-Nk, and PLP-Nv) were designed and tested against 28 samples, including 22 BER pathogen cultures, 4 closely related species, and 2 unrelated species that may cause serious apple decays. The assay successfully identified all the bull’s-eye rot pathogenic fungi at the level of species, while no cross-reaction was observed in all target species and no false-positive reaction was observed with all strains used for reference. This study showed that the use of padlock probes and the combination of probe signal amplification by RCA provided an effective and sensitive method for the rapid identification of Neofabraea spp. The method could therefore be a useful tool for monitoring bull’s-eye rot pathogens in port quarantine and orchard epidemiological studies.
3-D flow of a compressible viscous micropolar fluid model with spherical symmetry: A brief survey and recent progress
Authors: Dražić Ivan
Published: October 2017

We consider the non-stationary 3-D flow of a compressible viscous and heat-conducting micropolar fluid with the assumption of spherical symmetry. We analyze the flow between two concentric spheres that present solid thermo-insulated walls. The fluid is perfect and polytropic in the thermodynamical sense and the initial density and temperature are strictly positive. The corresponding problem has homogeneous boundary data.

In this work, we present the described model and provide a brief overview of the progress in the mathematical analysis of the associated initial-boundary problem. We consider existence and uniqueness of the generalized solution, asymptotic behavior of the solution and regularity of the solution.
The phosphorene under the external electronic field and strain
Authors: Wang Tao , Liu Yan , Wen Wen , Guo Wei , Yin You
Published: October 2017

Using the ab initio plane-wave ultrasoft pseudopotential method based on the generalized gradient approximation (GGA), we investigate the bandgap tuning in monolayer phosphorene in terms of applying external electric fields perpendicular to the layers. The bandgap continuously decreases with the applied electric fields, eventually rendering them metallic. The phenomenon is explained by the giant stark effect. The interlayer P-P distance also result in the semiconductor-to-metal transition. The phosphorene exhibits the significant bandgap tuning ability under different strains with 5% variation. Our investigations show the bandgap change for the fabrication of novel electronic and photonic devices.
Fibers of word maps and the multiplicities of non-abelian composition factors
Authors: Bors Alexander
Published: October 2017

We call a reduced word [Formula: see text] multiplicity-bounding if and only if a finite group on which the word map of [Formula: see text] has a fiber of positive proportion [Formula: see text] can only contain each non-abelian finite simple group [Formula: see text] as a composition factor with multiplicity bounded in terms of [Formula: see text] and [Formula: see text]. In this paper, based on recent work of Nikolov, we present methods to show that a given reduced word is multiplicity-bounding and apply them to give some nontrivial examples of multiplicity-bounding words, such as words of the form [Formula: see text], where [Formula: see text] is a single variable and [Formula: see text] an odd integer.
On rings of differential Rota–Baxter operators
Authors: Gao Xing , Guo Li , Rosenkranz Markus
Published: October 2017

Using the language of operated algebras, we construct and investigate a class of operator rings and enriched modules induced by a derivation or Rota–Baxter operator. In applying the general framework to univariate polynomials, one is led to the integro–differential analogs of the classical Weyl algebra. These are analyzed in terms of skew polynomial rings and noncommutative Gröbner bases.
Simultaneous stationary reflection and square sequences
Authors: Hayut Yair , Lambie-Hanson Chris
Published: October 2017

We investigate the relationship between weak square principles and simultaneous reflection of stationary sets.
Enhanced discrete wavelet packet sub-band frequency edge detection using Hilbert transform
Authors: Dibal P. Y. , Onwuka E. N. , Agajo J. , Alenoghena C. O.
Published: October 2017

The wavelet packet transform as a mathematical tool has found recent application in spectrum sensing. The result of this application has produced very promising results. Primarily, wavelets were designed for edge detection in images. Recently, cognitive radio literature have reported on wavelet application to detect sub-band frequency edges in wide band spectrum. In this paper, we present the combination of the Hilbert transform and the wavelet packet transform with the aim of enhancing the detection of the sub-band frequency edges of a wavelet-packet-decomposed signal. The simulation results show the effectiveness of this approach. The new scheme detected sub-band frequency edges of the wavelet-packet-decomposed signal much better than the wavelet packet transform without combination with the Hilbert transform.
HFBLMS: Hierarchical Fractional Bidirectional Least-Mean-Square prediction method for data reduction in wireless sensor network
Authors: Ganjewar Pramod D. , Barani S. , Wagh Sanjeev J.
Published: October 2017

Various Wireless Sensor Network (WSN) applications require the common task of collecting the data from the sensor nodes using the sink. Since the procedure of collecting data is iterative, an effective technique is necessary to obtain the data efficiently by reducing the consumption of nodal energy. Hence, a technique for data reduction in WSN is presented in this paper by proposing a prediction algorithm, called Hierarchical Fractional Bidirectional Least-Mean Square (HFBLMS) algorithm. The novel algorithm is designed by modifying Hierarchical Least-Mean Square (HLMS) algorithm with the inclusion of BLMS for bidirectional-based data prediction and Fractional Calculus (FC) in the weight update process. Data redundancy is achieved by transmitting only those data required based on the data predicted at the sensor node and the sink. Moreover, the proposed HFBLMS algorithm reduces the energy consumption in the network by the effective prediction attained by BLMS. Two metrics, such as energy consumption and prediction error, are used for the evaluation of performance of the HFBLMS prediction algorithm, where it can attain energy values of 0.3587 and 0.1953 at the maximum number of rounds and prediction errors of just 0.0213 and 0.0095, using air quality and localization datasets, respectively.
Phonological Knowledge and Speech Comprehension
Authors: Monahan Philip J.
Published: October 2017

Comprehending speech in our native language is an impressionistically effortless and routine task. We often give little consideration to its complexity. Only in particularly challenging situations (e.g., in noisy environments, when hearing significantly accented speech) do some of these intricacies become apparent. Higher-order knowledge constrains sensory perception and has been demonstrated to play a crucial role in other domains of human language processing. Moreover, incorporating measures of brain activity during online speech comprehension has just begun to highlight the extent to which top-down information flow and predictive processes are integral to sensory perception. This review argues that our phonological system, at a relatively abstract level, is one such source of higher-order knowledge. In particular, I discuss the extent to which phonological distinctive features play a role in perception and predictive processing during speech comprehension with reference to behavioral and neurophysiological data. This line of research represents a tractable linking of linguistic theory with models of perception and speech comprehension in the brain.
Novel Preparation of Fe Doped TiO2 Nanoparticles and Their Application for Gas Sensor and Photocatalytic Degradation
Authors: Eadi Sunil Babu , Kim Sungjin , Jeong Soon Wook , Jeon Heung Woo
Published: October 2017

The preparation of Fe doped TiO2 is demonstrated as well as application for gas sensing and photocatalytic degradation. Fe doped TiO2 nanopowder was prepared by the mechanochemical ball milling method. The results show the uniform doping of Fe in TiO2 powder. The average size of the particle is observed to be ~28 nm. The H2 gas sensor was fabricated using the Fe doped TiO2 nanopowder and the effect of Fe doping on the sensing properties is investigated with various temperature ranges. The prepared Fe doped TiO2 nanoparticles are also used to explore degradation properties of Rhodamine B dye under LED light.