bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy metabolism and the high‐altitude environment
Authors: Murray Andrew J.
Published: August 2015

New Findings

What is the topic of this review?

This report describes changes in cardiac and skeletal muscle energy metabolism that occur with exposure to high altitude and considers possible underlying mechanisms.

What advances does it highlight?

In the human heart, sustained hypoxia at high altitude or shorter‐term normobaric hypoxia result in a loss of cardiac energetic reserve. In the hypoxic rat heart, fatty acid oxidation and respiratory capacity fall. In skeletal muscle, prolonged exposure to extreme high altitude results in the loss of mitochondrial density, but even at more moderate high altitude the respiratory capacity may be suppressed. Evidence from cells, genetically modified mice and high‐altitude‐adapted Tibetans suggests a possible mechanistic role for the hypoxia‐inducible factor pathway.

At high altitude the barometric pressure falls, challenging oxygen delivery to the tissues. Thus, whilst hypoxia is not the only physiological stress encountered at high altitude, low arterial is a sustained feature, even after allowing adequate time for acclimatization. Cardiac and skeletal muscle energy metabolism is altered in subjects at, or returning from, high altitude. In the heart, energetic reserve falls, as indicated by lower phosphocreatine‐to‐ATP ratios. The underlying mechanism is unknown, but in the hypoxic rat heart fatty acid oxidation and respiratory capacity are decreased, whilst pyruvate oxidation is also lower after sustained hypoxic exposure. In skeletal muscle, there is not a consensus. With prolonged exposure to extreme high altitude (>5500 m) a loss of muscle mitochondrial density is seen, but this was not observed in a simulated ascent of Everest in hypobaric chambers. At more moderate high altitude, decreased respiratory capacity may occur without changes in mitochondrial volume density, and fat oxidation may be downregulated, although this is not seen in all studies. The underlying mechanisms, including the possible role of hypoxia‐signalling pathways, remain to be resolved, particularly in light of confounding factors in the high‐altitude environment. In high‐altitude‐adapted Tibetan natives, however, there is evidence of natural selection centred around the hypoxia‐inducible factor pathway, and metabolic features in this population (e.g. low cardiac phosphocreatine‐to‐ATP ratios, increased cardiac glucose uptake and lower muscle mitochondrial densities) share similarities with those in acclimatized lowlanders, supporting a possible role for the hypoxia‐inducible factor pathway in the metabolic response of cardiac and skeletal muscle energy metabolism to high altitude.
Local control of blood flow during active hyperaemia: what kinds of integration are important?
Authors: Murrant Coral L. , Sarelius Ingrid H.
Published: August 2015

The focus of this review is on local mechanisms modifying arteriolar resistance to match blood flow to metabolism. In skeletal muscle many local mediators are known, including K+, nitric oxide (NO), purines and prostaglandins. Each accounts for about 30% of the response; it is widely held that these act redundantly: this concept awaits systematic testing. Understanding signal integration also requires consideration of microvascular network morphology in relation to local communication pathways between endothelial and smooth muscle cells (which are critical for many local responses, including dilatation to skeletal muscle contraction) and in relation to the spread of vasodilator signals up‐ and downstream throughout the network. Mechanisms mediating the spread of dilatation from local to remote sites have been well studied using acetylcholine (ACh), but remote dilatations to contraction of skeletal muscle fibres also occur. Importantly, these mechanisms clearly differ from those initiated by ACh, but much remains undefined. Furthermore, capillaries contribute to metabolic dilatation as they dilate arterioles directly upstream in response to vasoactive agents or contraction of adjacent muscle fibres. Given the dispersed arrangement of motor units, precise matching of flow to metabolism is not attainable unless signals are initiated only by ‘active’ capillaries. As motor units are recruited, signals that direct blood flow towards these active fibres will eventually be supported by local and spreading responses in the arterioles associated with those fibres. Thus, mechanisms of integration of vasodilator signalling across elements of the microvasculature remain an important area of focus for new studies.

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Heart failure induces changes in acid‐sensing ion channels in sensory neurons innervating skeletal muscle
Authors: Gibbons David D. , Kutschke William J. , Weiss Robert M. , Benson Christopher J.
Published: August 2015

Key points

Heart failure is characterized by an elevated sympathetic state and exercise intolerance, which is partially driven by exaggerated autonomic reflexes triggered by skeletal muscle afferents.

Acid‐sensing ion channels (ASICs) are highly expressed in skeletal muscle afferents and contribute to exercise mediated reflexes.

Here we show that ASIC currents recorded from isolated skeletal muscle sensory neurons display diminished pH sensitivity, altered desensitization kinetics, and faster recovery from desensitization in a mouse model of heart failure.

These results indicate ASICs in muscle afferents are altered in heart failure, and may contribute to the associated sympathoexcitation and exercise intolerance.

Heart failure is associated with diminished exercise capacity, which is driven, in part, by alterations in exercise‐induced autonomic reflexes triggered by skeletal muscle sensory neurons (afferents). These overactive reflexes may also contribute to the chronic state of sympathetic excitation, which is a major contributor to the morbidity and mortality of heart failure. Acid‐sensing ion channels (ASICs) are highly expressed in muscle afferents where they sense metabolic changes associated with ischaemia and exercise, and contribute to the metabolic component of these reflexes. Therefore, we tested if ASICs within muscle afferents are altered in heart failure. We used whole‐cell patch clamp to study the electrophysiological properties of acid‐evoked currents in isolated, labelled muscle afferent neurons from control and heart failure (induced by myocardial infarction) mice. We found that the percentage of muscle afferents that displayed ASIC‐like currents, the current amplitudes, and the pH dose–response relationships were not altered in mice with heart failure. On the other hand, the biophysical properties of ASIC‐like currents were significantly different in a subpopulation of cells (40%) from heart failure mice. This population displayed diminished pH sensitivity, altered desensitization kinetics, and very fast recovery from desensitization. These unique properties define these channels within this subpopulation of muscle afferents as being heteromeric channels composed of ASIC2a and ‐3 subunits. Heart failure induced a shift in the subunit composition of ASICs within muscle afferents, which significantly altered their pH sensing characteristics. These results might, in part, contribute to the changes in exercise‐mediated reflexes that are associated with heart failure.
High‐frequency focal repetitive cerebellar stimulation induces prolonged increases in human pharyngeal motor cortex excitability
Authors: Vasant Dipesh H. , Michou Emilia , Mistry Satish , Rothwell John C , Hamdy Shaheen
Published: August 2015

Key points

Neurostimulation is a rapidly emerging approach to swallowing rehabilitation, but cerebellar stimulation has not been explored as a treatment. Such proposed therapies for post‐stroke dysphagia have required confirmation of physiological effects and optimisation of parameters in healthy humans prior to translational progression into patient groups.

There is strong evidence for a role of the cerebellum in swallowing physiology, but this relationship has been under‐explored.

Recently, single pulses of cerebellar magnetic stimulation have been shown to directly evoke responses from pharyngeal musculature and produce short‐term enhancement of cortico‐pharyngeal motor evoked potentials, suggesting the feasibility of a cerebellar approach to neurostimulation in the swallowing system.

We therefore examined multiple parameters of repetitive cerebellar magnetic stimulation and have described the optimal settings to provoke longer‐lasting changes in swallowing neurophysiology. Based on evidence from the post‐stroke dysphagia neurostimulation literature, these changes may have a therapeutic potential for swallowing rehabilitation.

Brain neurostimulation has been shown to modulate cortical swallowing neurophysiology in post‐stroke dysphagia with therapeutic effects which are critically dependent on the stimulation parameters. Cerebellar neurostimulation is, however, a novel, unexplored approach to modulation of swallowing pathways as a prelude to therapy for dysphagia. Here, we randomised healthy human subjects (n = 17) to receive one of five cerebellar repetitive TMS (rTMS) interventions (Sham, 1 Hz, 5 Hz, 10 Hz and 20 Hz) on separate visits to our laboratory. Additionally, a subset of subjects randomly received each of three different durations (50, 250, 500 pulses) of optimal frequency versus sham cerebellar rTMS. Prior to interventions subjects underwent MRI‐guided single‐pulse transcranial magnetic stimulation (TMS) to co‐localise pharyngeal and thenar representation in the cortex and cerebellum (midline and hemispheric) before acquisition of baseline motor evoked potential (MEP) recordings from each site as a measure of excitability. Post‐interventional MEPs were recorded for an hour and compared to sham using repeated measures ANOVA. Only 10 Hz cerebellar rTMS increased cortico‐pharyngeal MEP amplitudes (mean bilateral increase 52%, P = 0.007) with effects lasting 30 min post‐intervention with an optimal train length of 250 pulses (P = 0.019). These optimised parameters of cerebellar rTMS can produce sustained increases in corticobulbar excitability and may have clinical translation in future studies of neurogenic dysphagia.
Lipid analysis of eight human breast cancer cell lines with ToF-SIMS
Authors: Robinson Michael A. , Graham Daniel J. , Morrish Fionnuala , Hockenbery David , Gamble Lara J.
Published: August 2015

In this work, four triple negative (TN) cell lines, three ER+ and PR+ receptor positive (RP) cell lines, and one ER+, PR+, and HER2+ cell line were chemically distinguished from one another using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and principal component analysis (PCA). PCA scores separation was observed between the individual cell lines within a given classification (TN and RP) and there were distinctly different trends found in the fatty acid and lipid compositions of the two different classifications. These trends indicated that the RP cell lines separated out based on the carbon chain length of the lipids while the TN cell lines showed separation based on cholesterol-related peaks (in the positive ion data). Both cell types separated out by trends in fatty acid chain length and saturation in the negative ions. These chemical differences may be manifestations of unique metabolic processes within each of the different cell lines. Additionally, the HER2+ cell line was distinguished from three other RP cell types as having a unique distribution of fatty acids including anticorrelation to 18-carbon chain fatty acids. As these cell lines could not be grown in the same growth media, a combination of chemical fixation, rinsing, C60+ presputtering, and selection of cellular regions-of-interest is also presented as a successful method to acquire ToF-SIMS data from cell lines grown in different media.
Beating the bounds: Localized timing cues to word segmentation
Authors: White Laurence , Mattys Sven L. , Stefansdottir Linda , Jones Victoria
Published: August 2015

Prosody facilitates perceptual segmentation of the speech stream into a sequence of words and phrases. With regard to speech timing, vowel lengthening is well established as a cue to an upcoming boundary, but listeners' exploitation of consonant lengthening for segmentation has not been systematically tested in the absence of other boundary cues. In a series of artificial language learning experiments, the impact of durational variation in consonants and vowels on listeners' extraction of novel trisyllables was examined. Language streams with systematic lengthening of word-initial consonants were better recalled than both control streams without localized lengthening and streams where word-initial syllable lengthening was confined to the vocalic rhyme. Furthermore, where vowel-consonant sequences were lengthened word-medially, listeners failed to learn the languages effectively. Thus the structural interpretation of lengthening effects depends upon their localization, in this case, a distinction between lengthening of the onset consonant and the vocalic syllable rhyme. This functional division is considered in terms of speech-rate-sensitive predictive mechanisms and listeners' expectations regarding the occurrence of syllable perceptual centres.
Preparing to Take the Field: A Temporal Exploration of Stress, Emotion, and Coping in Elite Cricket
Authors: Miles Adam James , Neil Rich , Barker Jamie
Published: August 2015

The purpose of this study was to explore the stress, emotion, and coping (SEC) experiences of elite cricketers leading up to and on the day of their first competitive fixture of the season. Four elite male cricketers (M = 21.25, SD = 1.5) completed Stress and Emotion Diaries (SEDs) for the 7-day period leading up to and on the day of their first competitive fixture of the season. We then interviewed the cricketers to explore the content of the SEDs in more detail. We used semistructured interviews to glean insight into the stressors, cognitions, emotions, coping strategies, and behaviors. Inductive and deductive content data analysis provided a holistic and temporal exploration of the SEC process underpinned by the cognitive-motivational-relational theory of emotions (Lazarus, 1999). The results highlighted the ongoing and continuous nature of the SEC process while illustrating the coping strategies the cricketers used leading up to and on the day of competition.
Architecture of the fungal nuclear pore inner ring complex
Authors: Stuwe Tobias , Bley Christopher J. , Thierbach Karsten , Petrovic Stefan , Schilbach Sandra , Mayo Daniel J. , Perriches Thibaud , Rundlet Emily J. , Jeon Young E. , Collins Leslie N. , Huber Ferdinand M. , Lin Daniel H. , Paduch Marcin , Koide Akiko , Lu Vincent , Fischer Jessica , Hurt Ed , Koide Shohei , Kossiakoff Anthony A. , Hoelz André
Published: August 2015

Building a gate to the nucleus

Nuclear pore complexes form a gateway between the cytoplasm and the nucleus (see the Perspective by Ullman and Powers). Stuwe
et al.
combined structural, biochemical, and functional analyses to elucidate the architecture of a six-protein complex that makes up the inner ring of the fungal nuclear pore. This includes a central trimeric complex homologous to the Nup62 complex found in metazoans that is incorporated into the nuclear pore inner-ring complex. Chug
et al.
report the structure of the metazoan trimeric Nup62 complex. Neither study supports a model in which the pore can dilate and constrict. Instead they suggest a rigid pore in which flexible domains called FG repeats fill the channel and form a barrier that can be traversed by receptors that carry cargos across.

Science
, this issue pp.
56
and
106
; see also p.
33
Draft Genome Sequence of Aquamicrobium defluvii Strain W13Z1, a Psychrotolerant Halotolerant Hydrocarbon-Degrading Bacterium
Authors: Wang Xinxin , Jin Decai , Zhou Lisha , Zhang Zhuo
Published: August 2015

Aquamicrobium defluvii
W13Z1 was isolated from petroleum-contaminated drill cuttings from the Bohai Sea and could degrade petroleum hydrocarbon with 5% NaCl at 15°C. Here, we present the 4.8-Mb draft genome sequence of this strain, which may provide useful information about the mechanism of petroleum degradation in drill cuttings.
How reliable are Functional Movement Screening scores? A systematic review of rater reliability
Authors: Moran Robert W , Schneiders Anthony G , Major Katherine M , Sullivan S John
Published: August 2015

Background

Several physical assessment protocols to identify intrinsic risk factors for injury aetiology related to movement quality have been described. The Functional Movement Screen (FMS) is a standardised, field-expedient test battery intended to assess movement quality and has been used clinically in preparticipation screening and in sports injury research.

Aim

To critically appraise and summarise research investigating the reliability of scores obtained using the FMS battery.

Study design

Systematic literature review.

Methods

Systematic search of Google Scholar, Scopus (including ScienceDirect and PubMed), EBSCO (including Academic Search Complete, AMED, CINAHL, Health Source: Nursing/Academic Edition), MEDLINE and SPORTDiscus. Studies meeting eligibility criteria were assessed by 2 reviewers for risk of bias using the Quality Appraisal of Reliability Studies checklist. Overall quality of evidence was determined using van Tulder's levels of evidence approach.

Results

12 studies were appraised. Overall, there was a ‘moderate’ level of evidence in favour of ‘acceptable’ (intraclass correlation coefficient ≥0.6) inter-rater and intra-rater reliability for composite scores derived fromlivescoring. For inter-rater reliability of composite scores derived fromvideorecordings there was ‘conflicting’ evidence, and ‘limited’ evidence for intra-rater reliability. For inter-rater reliability based onlivescoring of individual subtests there was ‘moderate’ evidence of ‘acceptable’ reliability (κ≥0.4) for 4 subtests (Deep Squat, Shoulder Mobility, Active Straight-leg Raise, Trunk Stability Push-up) and ‘conflicting’ evidence for the remaining 3 (Hurdle Step, In-line Lunge, Rotary Stability).

Conclusions

This review found ‘moderate’ evidence that raters can achieve acceptable levels of inter-rater and intra-rater reliability of composite FMS scores when usingliveratings. Overall, there were few high-quality studies, and the quality of several studies was impacted by poor study reporting particularly in relation to rater blinding.
Changing trends of hospitalisation of liver cirrhosis in Beijing, China
Authors: Bao Xiao-Yuan , Xu Bei-Bei , Fang Kai , Li Yan , Hu Yong-Hua , Yu Guo-Pei
Published: August 2015

Objective

To examine if the hospitalisation trends of liver cirrhosis are changing with the changes of risk factors of the disease in China.

Design

Secondary analysis of hospitalisation records in the 31 top-ranking hospitals in Beijing.

Results

Between 2006 and 2010, hospitalisation from viral hepatitis cirrhosis (VHC) decreased by 10% (95% CI=5–14%, p<0.001), but non-viral hepatitis cirrhosis (NVHC) and alcoholic cirrhosis (AC) increased by 35% (26–46%, p<0.001) and 33% (19%– 47%, p<0.001), respectively. The age patterns of hospitalisation varied with different types of liver cirrhosis. The hospitalisation risks for patients with VHC and AC were significantly high in the age groups 40–49 and 50–59 years, but risks for those with NHVC were high in all age groups of 40 years or above. Overall male-to-female hospitalisation ratios for VHC, NVHC and AC were 2.71, 1.14 and 59.9, respectively. The sex ratio became smaller with time from 2006 to 2010 in hospitalised patients with VHC, but it substantially increased in those with NVHC during the same period.

Conclusions

Hospitalisation rates for liver cirrhosis in Beijing are changing with time. The changes of viral hepatitis infection and alcohol consumption in the general population may cause these changes.
Association between probable postnatal depression and increased infant mortality and morbidity: findings from the DON population-based cohort study in rural Ghana
Authors: Weobong Benedict , ten Asbroek Augustinus H A , Soremekun Seyi , Gram Lu , Amenga-Etego Seeba , Danso Samuel , Owusu-Agyei Seth , Prince Martin , Kirkwood Betty R
Published: August 2015

Objectives

To assess the impact of probable depression in the immediate postnatal period on subsequent infant mortality and morbidity.

Design

Cohort study nested within 4 weekly surveillance of all women of reproductive age to identify pregnancies and collect data on births and deaths.

Setting

Rural/periurban communities within the Kintampo Health Research Centre study area of the Brong-Ahafo Region of Ghana.

Participants

16 560 mothers who had a live singleton birth reported between 24 March 2008 and 11 July 2009, who were screened for probable postnatal depression (pPND) between 4 and 12 weeks post partum (some of whom had also had depression assessed at pregnancy), and whose infants survived to this point.

Primary/secondary outcome measures

All-cause early infant mortality expressed per 1000 infant-months of follow-up from the time of postnatal assessment to 6 months of age. The secondary outcomes were (1) all-cause infant mortality from the time of postnatal assessment to 12 months of age and (2) reported infant morbidity from the time of the postnatal assessment to 12 months of age.

Results

130 infant deaths were recorded and singletons were followed for 67 457.4 infant-months from the time of their mothers’ postnatal depression assessment. pPND was associated with an almost threefold increased risk of mortality up to 6 months (adjusted rate ratio (RR), 2.86 (1.58 to 5.19); p=0.001). The RR up to 12 months was 1.88 (1.09 to 3.24; p=0.023). pPND was also associated with increased risk of infant morbidity.

Conclusions

There is new evidence for the association between maternal pPND and infant mortality in low-income and middle-income countries. Implementation of the WHO's Mental Health Gap Action Programme (mhGAP) to scale up packages of care integrated with maternal health is encouraged as an important adjunct to child survival efforts.
Development of a multivariable model to predict vulnerability in older American patients hospitalised with cardiovascular disease
Authors: Bell Susan P , Schnelle John , Nwosu Samuel K , Schildcrout Jonathan , Goggins Kathryn , Cawthon Courtney , Mixon Amanda S , Vasilevskis Eduard E , Kripalani Sunil
Published: August 2015

Objectives

To identify vulnerable cardiovascular patients in the hospital using a self-reported function-based screening tool.

Participants

Prospective observational cohort study of 445 individuals aged ≥65 years admitted to a university medical centre hospital within the USA with acute coronary syndrome and/or decompensated heart failure.

Methods

Participants completed an inperson interview during hospitalisation, which included vulnerable functional status using the Vulnerable Elders Survey (VES-13), sociodemographic, healthcare utilisation practices and clinical patient-specific measures. A multivariable proportional odds logistic regression model examined associations between VES-13 and prior healthcare utilisation, as well as other coincident medical and psychosocial risk factors for poor outcomes in cardiovascular disease.

Results

Vulnerability was highly prevalent (54%) and associated with a higher number of clinic visits, emergency room visits and hospitalisations (all p<0.001). A multivariable analysis demonstrating a 1-point increase in VES-13 (vulnerability) was independently associated with being female (OR 1.55, p=0.030), diagnosis of heart failure (OR 3.11, p<0.001), prior hospitalisations (OR 1.30, p<0.001), low social support (OR 1.42, p=0.007) and depression (p<0.001). A lower VES-13 score (lower vulnerability) was associated with increased health literacy (OR 0.70, p=0.002).

Conclusions

Vulnerability to functional decline is highly prevalent in hospitalised older cardiovascular patients and was associated with patient risk factors for adverse outcomes and an increased use of healthcare services.
Geospatial patterns of human papillomavirus vaccine uptake in Minnesota
Authors: Nelson Erik J , Hughes John , Oakes J Michael , Pankow James S , Kulasingam Shalini L
Published: August 2015

Objectives

To identify factors associated with human papillomavirus (HPV) vaccination and to determine the geographic distribution of vaccine uptake while accounting for spatial autocorrelation.

Design

This study is cross-sectional in design using data collected via the Internet from the Survey of Minnesotans About Screening and HPV study.

Setting and participants

The sample consists of 760 individuals aged 18–30 years nested within 99 ZIP codes surrounding the downtown area of Minneapolis, Minnesota.

Results

In all, 46.2% of participants had received≥1 dose of HPV vaccine (67.7% of women and 13.0% of men). Prevalence of HPV vaccination was found to exhibit strong spatial dependence () across ZIP codes. Accounting for spatial dependence, age (OR=0.76, 95% CI 0.70 to 0.83) and male gender (OR=0.04, 95% CI 0.03 to 0.07) were negatively associated with vaccination, while liberal political preferences (OR=4.31, 95% CI 2.32 to 8.01), and college education (OR=2.58, 95% CI 1.14 to 5.83) were found to be positively associated with HPV vaccination.

Conclusions

Strong spatial dependence and heterogeneity of HPV vaccination prevalence were found across ZIP codes, indicating that spatial statistical models are needed to accurately identify and estimate factors associated with vaccine uptake across geographic units. This study also underscores the need for more detailed data collected at local levels (eg, ZIP code), as patterns of HPV vaccine receipt were found to differ significantly from aggregated state and national patterns. Future work is needed to further pinpoint areas with the greatest disparities in HPV vaccination and how to then access these populations to improve vaccine uptake.
Multi-scale laboratory evaluation of the physical, mechanical, and microstructural properties of soft highway subgrade soil stabilized with calcium carbide residue
Authors: Jiang Ning-Jun , Du Yan-Jun , Liu Song-Yu , Wei Ming-Li , Horpibulsuk Suksun , Arulrajah Arul
Published: August 2015

Calcium carbide residue (CCR) is an industrial by-product, stockpiles of which are rapidly accumulating worldwide. Highway embankment construction has been identified as an avenue to consume huge quantities of CCR as an economical, less energy intensive, and environmentally friendly chemical additive for soil stabilization. Previous studies have investigated the mechanical behavior of soils stabilized by CCR or blends of CCR with other additives; however, interpretation of the macroscale geomechanical behavior of CCR-stabilized soft soils from a systematically microstructural observation and analysis is relatively unknown. This paper presents a multi-scale laboratory investigation on the physical, mechanical, and microstructural properties of CCR-stabilized clayey soils with comparison to quicklime-stabilized soils. Several series of tests were conducted to examine the Atterberg limits, particle-size distribution, compaction characteristics, unconfined compressive strength, California Bearing Ratio, and resilient modulus of the CCR-stabilized clayey soils. The influences of binder content, curing time, and initial compaction state on the physical and mechanical properties of treated soils are interpreted with the aids of physicochemical and microstructural observations including soil pH, soil mineralogy obtained from X-ray diffraction and thermogravimetric analysis, and pore-size distribution obtained from mercury intrusion porosimetry. Soil particle flocculation and agglomeration at the early stage and pozzolanic reactions during the entire curing time, which originate from the finer particle size, greater specific surface area, and higher pH value of CCR, are the controlling mechanisms for the superior mechanical performance of CCR-stabilized soils. The outcomes of this research will contribute to the usage of CCR as a sustainable and alternative stabilizer to quicklime in highway embankment applications.
Seismic fragility of steel moment-resisting frames in Vancouver and Montreal designed in the 1960s, 1980s, and 2010
Authors: Gómez Lucía Valentina Díaz , Kwon Oh-Sung , Dabirvaziri Mohammad Reza
Published: August 2015

Typical steel moment-resisting frames (MRF) of six-storey buildings in Vancouver and Montreal were designed for three different provisions of the National Building Code of Canada (1960s, 1980s, and 2010). Numerical models were developed in OpenSees to understand the seismic performance of the structures. These models accounted for strength and stiffness degradation through appropriate representations of the beam–column connection behaviours, which were calibrated against experimental results available in the literature. The behaviour of the buildings was evaluated through pushover and nonlinear time history analyses. The pushover analysis results showed that the 1960s and 2010 steel MRFs of both cities exhibited strong-column-weak-beam failure mode. The 1980s steel MRFs of both cities showed soft-storey mechanism. Fragility curves were developed for the steel MRFs based on the seismic demands evaluated using nonlinear time history analyses, which can be used for regional seismic impact assessment studies in the future.
Probabilistic assessment of a design truck model and live load factor from weigh-in-motion data for Mexican Highway bridge design
Authors: García-Soto A.D. , Hernández-Martínez A. , Valdés-Vázquez J.G.
Published: August 2015

This study is focused on the statistical characterization of live load effects on bridges using weigh-in-motion data from a Mexican highway. A truck load model that is simpler than the design truck model implemented in the current Mexican requirements is suggested for design. The statistics are employed in target-reliability based calibration and verification of load factors in Mexican bridge design. Suggestions that could be useful for the Canadian bridge engineering practice are included.
Properties of cold dense nuclear matter based on a developed chiral perturbation theory
Authors: Wang Qingwu , Li Xiaoya , Lü Xiaofu
Published: August 2015

A developed effective chiral Lagrangian approach is used to study the cold dense nuclear matter. Improved calculation of baryon number density as a function of chemical potential is given. The resonance appeared in a natural way as chemical potential is getting larger. Calculations of susceptibility and pressure including the resonance contribution are also given.
Nonlinear Vibration of Single-Walled Carbon Nanotubes Under Magnetic Field by Stochastic Finite Element Method
Authors: Chang T.-P.
Published: August 2015

In the present study, we investigate the statistical nonlinear dynamic behaviors of a single-walled carbon nanotube (SWCNT) subjected to a longitudinal magnetic field by considering the effect of geometric nonlinearity. We consider both the Young’s modulus of elasticity and mass density of the SWCNT as stochastic with respect to the position to actually characterize the random material properties of the SWCNT. In addition, we use the theory of nonlocal elasticity to investigate the small scale effect on the nonlinear vibration of the SWCNT. By using the Hamilton’s principle, the nonlinear governing equations of the SWCNT subjected to a longitudinal magnetic field are derived. We utilize the stochastic finite element method along with the perturbation technique to compute the statistical response of the SWCNT. Some statistical dynamic response of the SWCNT, such as the mean values and standard deviations of the midpoint deflections, are computed and checked by the Monte Carlo simulation, besides, the effects of the small scale coefficients, magnetic field and the elastic stiffness of matrix on the statistical dynamic response of the SWCNT are studied and discussed.
A Multi-Point Tire Model for Studying Bridge–Vehicle Coupled Vibration
Authors: Deng Lu , Cao Ran , Wang Wei , Yin Xinfeng
Published: August 2015

The contact between a vehicle tire and the road surface has been usually assumed as a single-point contact in the numerical simulation of vehicle–bridge interacted vibrations. In reality, the tire contacts the road surface through a patch instead of a single point. According to some recent studies, the single-point tire model may overestimate the dynamic amplification of bridge responses due to vehicle loadings. A new tire model, namely, the multi-point tire model, is therefore proposed in this paper with the purpose of improving the accuracy of numerical simulation results over the single-point model, while maintaining a certain level of simplicity for applications. A series of numerical simulations are carried out to compare the effect of the proposed tire model with those of the existing single-point model and disk model on the bridge dynamic responses. The proposed tire model is also verified against the field test results. The results show that the proposed multi-point tire model can predict the bridge dynamic responses with better accuracy than the single-point model, especially under distressed bridge deck conditions, and is computationally more efficient and simpler for application than the disk model.
Resolving complex communication beyond geological and geophysical data resolution: an example from an underground gas storage facility in the Austrian Molasse Basin
Authors: Thürschmid G. , Harrer A. , Gruber W. , Griess B.
Published: August 2015

A fully integrated reservoir modelling approach aiming for the best conditioned static model for an underground gas storage facility (UGSF) in a complex structural and depositional setting is presented.

The Nussdorf UGSF is a depleted gas field characterized by typical deep-water depositional environment settings including sediment mass-flow systems being shed off the emerging Alpine thrust front during the Neogene. The key challenge in assessing this specific storage performance is the communication within the individual stacked sandstone layers, as well as determining the existing cross-flow between such layers through wells and due to juxtaposition across faults.

Highly heterogeneous reservoir facies, representing thin-layered, stacked sandy fans embedded in marly shale, were realized by joining object-based and Gaussian simulations constrained by a gross depositional environment model. Modelling known pressure communication across intrareservoir faults required fault throws to be adjusted at scales below the limit of seismic resolution. Scoping simulation runs on a best-guess model led to a full back-loop of the geological modelling. Several loops revealed that iterations limited to property realizations were insufficient, requiring additional modifications of the structural model. Only via this expensive approach could a geologically consistent and ‘fit for purpose’ reservoir model for the UGSF be achieved.
Mesenchymal stromal cell therapy in liver disease: opportunities and lessons to be learnt?
Authors: Owen Andrew , Newsome Philip N.
Published: August 2015

End-stage liver disease is responsible for 30,000 deaths per year in the United States alone, and it is continuing to increase every year. With liver transplantation the only curative treatment currently available, new therapies are in great demand. Mesenchymal stem cells (MSC) offer an opportunity to both treat liver inflammatory damage, as well as reverse some of the changes that occur following chronic liver injury. With the ability to regulate both the innate and adaptive immune system, as well as both inhibit and promote apoptosis of effector inflammatory cells, there are numerous therapeutic opportunities for MSC in acute and chronic liver disease. This article critically appraises the potential therapeutic roles of MSC in liver disease, as well as the barriers to their adoption into clinical practice.
Effect of age on long-term facilitation and chemosensitivity during NREM sleep
Authors: Chowdhuri Susmita , Pranathiageswaran Sukanya , Franco-Elizondo Rene , Jayakar Arunima , Hosni Arwa , Nair Ajin , Badr M. Safwan
Published: August 2015

The reason for increased sleep-disordered breathing with a predominance of central apneas in the elderly is unknown. We speculate that ventilatory control instability may provide a link between aging and the onset of unstable breathing during sleep. We sought to investigate potential underlying mechanisms in healthy, elderly adults during sleep. We hypothesized that there is 1) a decline in respiratory plasticity or long-term facilitation (LTF) of ventilation and/or 2) increased ventilatory chemosensitivity in older adults during non-, this should be hyphenated, non-rapid rapid eye movement (NREM) sleep. Fourteen elderly adults underwent 15, 1-min episodes of isocapnic hypoxia (EH), nadir O2saturation: 87.0 ± 0.8%. Measurements were obtained during control, hypoxia, and up to 20 min of recovery following the EH protocol, respectively, for minute ventilation (VI), timing, and inspiratory upper-airway resistances (RUA). The results showed the following. 1) Compared with baseline, there was a significant increase in VI(158 ± 11%, P < 0.05) during EH, but this was not accompanied by augmentation of VIduring the successive hypoxia trials nor in VIduring the recovery period (94.4 ± 3.5%, P = not significant), indicating an absence of LTF. There was no change in inspiratory RUAduring the trials. This is in contrast to our previous findings of respiratory plasticity in young adults during sleep. Sham studies did not show a change in any of the measured parameters. 2) We observed increased chemosensitivity with increased isocapnic hypoxic ventilatory response and hyperoxic suppression of VIin older vs. young adults during NREM sleep. Thus increased chemosensitivity, unconstrained by respiratory plasticity, may explain increased periodic breathing and central apneas in elderly adults during NREM sleep.
Beneficial and detrimental role of adenosine signaling in diseases and therapy
Authors: Liu Hong , Xia Yang
Published: August 2015

Adenosine is a major signaling nucleoside that orchestrates cellular and tissue adaptation under energy depletion and ischemic/hypoxic conditions by activation of four G protein-coupled receptors (GPCR). The regulation and generation of extracellular adenosine in response to stress are critical in tissue protection. Both mouse and human studies reported that extracellular adenosine signaling plays a beneficial role during acute states. However, prolonged excess extracellular adenosine is detrimental and contributes to the development and progression of various chronic diseases. In recent years, substantial progress has been made to understand the role of adenosine signaling in different conditions and to clarify its significance during the course of disease progression in various organs. These efforts have and will identify potential therapeutic possibilities for protection of tissue injury at acute stage by upregulation of adenosine signaling or attenuation of chronic disease progression by downregulation of adenosine signaling. This review is to summarize current progress and the importance of adenosine signaling in different disease stages and its potential therapeutic effects.
Two Novel Variants on 13q22.1 Are Associated with Risk of Esophageal Squamous Cell Carcinoma
Authors: Chang Jiang , Wei Lixuan , Miao Xiaoping , Yu Dianke , Tan Wen , Zhang Xuemei , Wu Chen , Lin Dongxin
Published: August 2015

Background: Chromosome 13q22.1 has previously been identified to be a susceptibility locus for pancreatic cancer in Chinese and European ancestry populations. This pleiotropy study aimed to identify novel variants in this region associated with susceptibility to different types of human cancer.

Method: To fine-map the 13q22.1 region, imputation analyses were conducted on the basis of the GWAS data of 2,031 esophageal squamous cell cancer (ESCC) cases and 2,044 controls and 5,930 SNPs (625 directly genotyped and 5,305 well imputed). Promising associations were then examined in ESCC (4,146 cases and 4,135 controls), gastric cardia cancer (1,894 cases and 1,912 controls), noncardia gastric cancer (1,007 cases and 2,243 controls), and colorectal cancer (1,111 cases and 1,138 controls). Fine mapping and biochemical analyses were further performed to elucidate the potential function of novel variants.

Results: Two novel variants, rs1924966 and rs115797771, were associated with ESCC risk (P = 1.37 × 10−10 and P = 2.32 × 10−10, respectively) and were also associated with risk of gastric cardia cancer (P = 0.0003 and P = 0.0018, respectively) but not gastric cancer and colorectal cancer. Fine-mapping revealed another SNP, rs58090485, in strong linkage disequilibrium with rs115797771 (r2 = 0.94). Functional analysis showed that this SNP disturbs a transcriptional repressor binding to the promoter region of KLF5, which might result in high constitutional expression of KLF5.

Conclusions: These results demonstrate that variants mapped on 13q22.1 are associated with the risk of different types of cancer.

Impact: 13q22.1 might serve as a biomarker for the identification of individuals at risk for ESCC and gastric cardia cancer. Cancer Epidemiol Biomarkers Prev; 24(11); 1774–80. ©2015 AACR.
Octreotide Long-Acting Repeatable among Elderly Patients with Neuroendocrine Tumors: A Survival Analysis of SEER-Medicare Data
Authors: Shen Chan , Shih Ya-Chen Tina , Xu Ying , Yao James C.
Published: August 2015

Background: Octreotide long-acting repeatable (LAR) is approved in the United States for the management of carcinoid syndromes among patients with neuroendocrine tumors (NET). The objective of our study is to evaluate the impact of octreotide LAR on overall survival (OS), as it has not been established.

Methods: NET patients of 65 years and older diagnosed between January 1999 and December 2009 were identified from the SEER-Medicare database. We compared the OS of NET patients who started octreotide LAR within 12 months of diagnosis with those who did not receive it during the same period. We conducted Kaplan–Meier estimations and Cox proportional hazard models to examine the association between octreotide LAR and OS.

Results: Among 1,176 distant stage patients, 233 (20%) received octreotide LAR within 12 months of diagnosis, compared with 2% (96 in 5,764) of local/regional stage patients. Median OS for patients who started octreotide LAR within 12 months was 35.22 months [95% confidence interval (CI), 27.96–47.77], longer than those who did not receive it (19.15 months; 95% CI, 16.36–22.80; P < 0.0001). Multivariate analysis showed that octreotide LAR was associated with significant survival improvement for distant stage patients (HR, 0.68; P < 0.001) and in the subgroups with (HR, 0.65; P, 0.003) and without (HR, 0.55; P, 0.002) carcinoid syndrome. No survival benefit was found among local/regional stage patients.

Conclusion: This population-based study suggests potential survival benefits of octreotide LAR among elderly distant stage NET patients, both with or without carcinoid syndrome.

Impact: The study provides population-based evidence of a positive association between octreotide LAR and overall survival among elderly distant stage NET patients. Cancer Epidemiol Biomarkers Prev; 24(11); 1656–65. ©2015 AACR.
Plasma MicroRNAs as Novel Biomarkers for Patients with Intraductal Papillary Mucinous Neoplasms of the Pancreas
Authors: Permuth-Wey Jennifer , Chen Dung-Tsa , Fulp William J. , Yoder Sean J. , Zhang Yonghong , Georgeades Christina , Husain Kazim , Centeno Barbara Ann , Magliocco Anthony M. , Coppola Domenico , Malafa Mokenge
Published: August 2015

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal cancers worldwide, partly because methods are lacking to detect disease at an early, operable stage. Noninvasive PDAC precursors called intraductal papillary mucinous neoplasms (IPMN) exist, and strategies are needed to aid in their proper diagnosis and management. Data support the importance of miRNAs in the progression of IPMNs to malignancy, and we hypothesized that miRNAs may be shed from IPMN tissues and detected in blood. Our primary goals were to measure the abundance of miRNAs in archived preoperative plasma from individuals with pathologically confirmed IPMNs and healthy controls and discover plasma miRNAs that distinguish between IPMN patients and controls and between “malignant” and “benign” IPMNs. Using novel nCounter technology to evaluate 800 miRNAs, we showed that a 30-miRNA signature distinguished 42 IPMN cases from 24 controls [area underneath the curve (AUC) = 74.4; 95% confidence interval (CI), 62.3–86.5, P = 0.002]. The signature contained novel miRNAs and miRNAs previously implicated in pancreatic carcinogenesis that had 2- to 4-fold higher expression in cases than controls. We also generated a 5-miRNA signature that discriminated between 21 malignant (high-grade dysplasia and invasive carcinoma) and 21 benign (low- and moderate-grade dysplasia) IPMNs (AUC = 73.2; 95% CI, 57.6–88.9, P = 0.005), and showed that paired plasma and tissue samples from patients with IPMNs can have distinct miRNA expression profiles. This study suggests feasibility of using new cost-effective technology to develop a miRNA-based blood test to aid in the preoperative identification of malignant IPMNs that warrant resection while sparing individuals with benign IPMNs the morbidity associated with overtreatment. Cancer Prev Res; 8(9); 826–34. ©2015 AACR.
Country Differences and Changes in Focus of Scientific Tobacco Control Publications between 2000 and 2012 in Europe
Authors: Willemsen Marc C. , Nagelhout Gera E.
Published: August 2015

Background/Aims: The Framework Convention on Tobacco Control (FCTC) stresses the importance of scientific research. We examined the differences between 31 European countries regarding quantity and focus of tobacco control research publications. Methods: PubMed, Web of Science, Scopus, and PsycInfo were searched for peer-reviewed articles on tobacco, written by European authors, published between 2000 and 2012. For 2000, 2004, 2008, and 2012 we further identified the main focus of the publication. Results: The volume of European tobacco control scientific publications had almost doubled. Scandinavian countries had most publications per inhabitant, while Bulgaria, Cyprus, Estonia, Latvia, Lithuania, Malta, Romania, Slovakia, and Slovenia had relatively little research output. There was a smaller increase in publications about harm from tobacco, relative to publications about treatment, and education, and to publications about environmental interventions. In 2012, 49% of all publications were about health, while the total number of publications on environmental interventions was relatively small (10%). Conclusion: Research output had almost doubled, in line with global trends, but is still unevenly distributed across Europe. Although we observed a shift in European publications away from the harm of tobacco towards protecting smokers and changing the environment, the field is still dominated by publications on smoking and health.