bluuebunny/crossref_metadata_2025 huggingface dataset:
Afferent connections of the thalamic nucleus reuniens in the mouse
Authors: Scheel Niklas , Wulff Peer , de Mooij‐van Malsen Johanne G.
Published: November 2019

The nucleus reuniens (RE) is part of the midline thalamus and one of the major sources of thalamic inputs to the hippocampal formation and the medial prefrontal cortex. However, it not only sends strong efferents to these areas but is also heavily innervated by both brain regions. Based on its connectivity and supported by functional studies the RE has been suggested to represent a major hub in reciprocal hippocampal–prefrontal communication. Indeed, inactivation studies have demonstrated that this nucleus is particularly important for cognitive behaviors which depend on prefrontal–hippocampal communication, such as working memory or memory consolidation. However, besides its central role in mediating hippocampal–prefrontal communication, the RE is target of a multitude of other cortical and subcortical afferents, which likely modulate its function. So far, however, studies that have systematically investigated the afferents of the RE have only been performed in rats. Because of the unique role of the mouse as a genetically accessible model system for mammalian brain circuit analysis we have mapped the afferent connectivity of the mouse RE using retrograde Fluoro‐Gold tracing. Comparison with similar data from rats indicated a very high level of similarity in prefrontal and hippocampal afferents but some differences in afferent connectivity with other brain regions. In particular, our results suggest interspecies differences regarding the integration of the RE in circuits of fear, aversion, and defense.
Hierarchical Roofline analysis for GPUs: Accelerating performance optimization for the NERSC‐9 Perlmutter system
Authors: Yang Charlene , Kurth Thorsten , Williams Samuel
Published: November 2019

The Roofline performance model provides an intuitive and insightful approach to identifying performance bottlenecks and guiding performance optimization. In preparation for the next‐generation supercomputer Perlmutter at NERSC, this paper presents a methodology to construct a hierarchical Roofline on NVIDIA GPUs and extends it to support reduced precision and Tensor Cores. The hierarchical Roofline incorporates L1, L2, device memory, and system memory bandwidths into one single figure, and it offers more profound insights into performance analysis than the traditional DRAM‐only Roofline. We use our Roofline methodology to analyze three proxy applications: GPP from BerkeleyGW, HPGMG from AMReX, and conv2d from TensorFlow. In doing so, we demonstrate the ability of our methodology to readily understand various aspects of performance and performance bottlenecks on NVIDIA GPUs and motivate code optimizations.
Antibody Panel Based N‐Glycan Imaging for N‐Glycoprotein Biomarker Discovery
Authors: Black Alyson P. , Angel Peggi M. , Drake Richard R. , Mehta Anand S.
Published: November 2019

Antibody panel based N‐glycan imaging is a novel platform for N‐glycan analysis of immunocaptured proteins. N‐glycosylation is a post‐translational modification of pathophysiological importance and is often studied in the context of disease biomarkers. Determination of protein‐specific N‐glycosylation changes in patient samples has traditionally been laborious or limited to study of a single protein per analysis. This novel technique allows for the multiplexed analysis of N‐glycoproteins from biofluids. Briefly, this platform consists of antibodies spotted in an array panel to a microscope slide, specific capture of glycoproteins from a biological sample, and then enzymatic release of N‐glycans for analysis by matrix‐assisted laser desorption/ionization (MALDI) mass spectrometry (MS). N‐glycans are detected at each individual spot, allowing N‐glycan information to easily be linked back to its protein carrier. Using this protocol, multiplexed analysis of N‐glycosylation on serum glycoproteins can be performed. Human serum is discussed here, but this method has potential to be applied to other biofluids and to any glycoprotein that can be captured by a validated antibody. © 2019 by John Wiley & Sons, Inc.

Basic Protocol: Antibody panel based N‐glycan imaging by MALDI MS

Support Protocol: Confirmation of antibody capture by IR‐labeled proteins
Distinguishing naive‐ from memory‐derived human B cells during acute responses
Authors: Auladell Maria , Nguyen Thi Ho , Garcillán Beatriz , Mackay Fabienne , Kedzierska Katherine , Fox Annette
Published: November 2019

Objectives

A fundamental question in influenza research is whether antibody titre decline upon successive exposure to variant strains is consequent to recall of cross‐reactive memory B cells that competitively inhibit naive B‐cell responses. In connection, it is not clear whether naive and memory B cells remain phenotypically distinct acutely after activation such that they may be distinguished ex vivo.

Methods

Here, we first compared the capacity of anti‐Ig and Toll‐like‐receptor (TLR) 7/8 and TLR9 agonists (R848 and CpG) to augment human B‐cell differentiation induced by IL‐21 and sCD40L. The conditions that induced optimal differentiation were then used to compare the post‐activation phenotype of sort‐purified naive and memory B‐cell subsets by FACS and antibody‐secreting cell (ASC) ELISPOT.

Results

Sort‐purified naive and memory B cells underwent robust plasmablast and ASC formation when stimulated with R848, but not CpG, and co‐cultured with monocytes. This coincided with increased IL‐1β and IL‐6 production when B cells were co‐cultured with monocytes and stimulated with R848, but not CpG. Naive B cells underwent equivalent ASC generation, but exhibited less class‐switch and modulation of CD27, CD38 and CD20 expression than memory B cells after stimulation with R848 and monocytes for 6 days.

Conclusion

Stimulation with R848, IL‐21 and sCD40L in the presence of monocytes induces robust differentiation and ASC generation from both naive and memory B‐cells. However, naive and memory B cells retain key phenotypic differences after activation that may facilitate ex vivo discrimination and better characterisation of acute responses to variant antigens.
A novel software‐defined networking approach for load balancing in data center networks
Authors: Chakravarthy V. Deeban , Amutha Balakrishnan
Published: November 2019

In today's modern era, the internet usage has been developing tremendously. In data center network (DCN), the traffic has been rising constantly in the past few years. Hence, greater traffic of network needs several services such as Domain Name Service (DNS) to manage. It is not possible for one server to manage entire requests coming from client because of huge amount of traffic. To resolve this issue, load balancing is used. The major purpose of load balancing is to forward incoming client requests and distribute the traffic across various servers using customized algorithm which is deployed in the load balancer. Traditional load balancers are very costly and inflexible hardware. A substitute of this hardware is to use software‐defined network load balancers. The software‐defined networking (SDN) load balancers offer the facility to programmers to design and construct their own strategy of load balancing, which makes the software‐defined network load balancer flexible and programmable. This research proposes a novel algorithm that performs load balancing through calculating in advance the capacity of each and every switch across the path to which the packets are routed.
Water stratification in the marine biome restricts vertical environmental DNA (eDNA) signal dispersal
Authors: Jeunen Gert‐Jan , Lamare Miles D. , Knapp Michael , Spencer Hamish G. , Taylor Helen R. , Stat Michael , Bunce Michael , Gemmell Neil J.
Published: November 2019

Background

The utility of environmental DNA (eDNA) metabarcoding surveys to accurately detect species depends on the degree of DNA dispersal. Multiple marine studies have observed only minimal eDNA transport by horizontal water movement across small spatial scales, leading to the conclusion that spatially specific eDNA signals accurately resemble in‐field species assemblages along a horizontal axis. Marine communities, however, are also structured vertically according to depth. In marine environments displaying permanent water stratification, vertical zonation patterns may be more apparent and present on smaller spatial scales (i.e., meters) than horizontal community structuring. The scale at which eDNA signals differ along a vertical transect and the accuracy of eDNA metabarcoding in revealing naturally stratified communities have yet to be assessed.

Methods and results

In this study, we determined the ability of eDNA metabarcoding surveys to distinguish vertically localized community assemblages. To test this, we sampled three vertical transects along a steep rock wall at three depths (0 m, 4 m, 15 m), covering two distinct communities that were separated by near‐permanent water column stratification in the form of a strong halocline at ~3 m. Using three metabarcoding assays, our eDNA metabarcoding survey detected 54 taxa, across 46 families and 7 phyla, including 19 fish, 15 crustacean, and 8 echinoderm species. Ordination and cluster analyses show distinct eDNA signals across the halocline for all three replicate transects, suggesting that vertical dispersal of eDNA between communities was limited. Furthermore, eDNA signals of individual taxa were only retrieved within their observed vertical distribution, providing biological validation for the obtained results. Our results demonstrate, for the first time, the need to take into consideration oceanographic (e.g. water column stratification) and biological processes (e.g. vertical community structuring) when designing sampling strategies for marine eDNA metabarcoding surveys.
Heart failure after treatment for breast cancer
Authors: Boekel Naomi B. , Duane Fran K. , Jacobse Judy N. , Hauptmann Michael , Schaapveld Michael , Sonke Gabe S. , Gietema Jourik A. , Hooning Maartje J. , Seynaeve Caroline M. , Maas Angela H.E.M. , Darby Sarah C. , Aleman Berthe M.P. , Taylor Carolyn W. , van Leeuwen Flora E.
Published: November 2019

Background

We aimed to develop dose–response relationships for heart failure (HF) following radiation and anthracyclines in breast cancer treatment, and to assess HF associations with trastuzumab and endocrine therapies.

Methods and results

A case–control study was performed within a cohort of breast cancer survivors treated during 1980–2009. Cases (n = 102) had HF as first cardiovascular diagnosis and were matched 1:3 on age and date of diagnosis. Individual cardiac radiation doses were estimated, and anthracycline doses and use of trastuzumab and endocrine therapy were abstracted from oncology notes. For HF cases who received radiotherapy, the estimated median mean heart dose (MHD) was 6.8 Gy [interquartile range (IQR) 0.9–13.7]. MHD was not associated with HF risk overall [excess rate ratio (ERR) = 1%/Gy, 95% confidence interval (CI) −2 to 10]. In patients treated with anthracyclines, exposure of ≥20% of the heart to ≥20 Gy was associated with a rate ratio of 5.7 (95% CI 1.7–21.7) compared to <10% exposed to ≥20 Gy. For cases who received radiotherapy, median cumulative anthracycline dose was 247 mg/m2 (IQR 240–319). A dose‐dependent increase was observed after anthracycline without trastuzumab (ERR = 1.5% per mg/m2, 95% CI 0.5–4.1). After anthracycline and trastuzumab, the rate ratio was 34.9 (95% CI 11.1–110.1) compared to no chemotherapy.

Conclusions

In absence of anthracyclines, breast cancer radiotherapy was not associated with increased HF risk. Strongly elevated HF risks were observed after treatment with anthracyclines and also after treatment with trastuzumab. The benefits of these systemic treatments usually exceed the risks of HF, but our results emphasize the need to support ongoing efforts to evaluate preventative strategies.
Tailored Synthesis of Coral‐Like CoTiO3/Co3O4/TiO2 Nanobelts with Superior Lithium Storage Capability
Authors: Liu Hao , Wu Xiaona , Guo Enyan , Lu Qifang
Published: November 2019

A facile yet efficient two‐step electrospinning calcination strategy is smartly developed to construct 1D hierarchical coral‐like CoTiO3/Co3O4/TiO2 hybrid nanobelts. The 1D coral‐like nanohybrid is homogeneously constructed from well‐dispersed CoTiO3 nanobelts and uniformly distributed secondary crystalline Co3O4/TiO2 nanoparticle building blocks. When evaluated as anodes for lithium‐ion batteries (LIBs), the hybrid CoTiO3/Co3O4/TiO2 nanobelt electrode exhibits a promising reversible capacity of 722.3 mAh g−1 at 100 mA g−1 after 250 cycles and has excellent cyclability with a capacity of 256.7 mAh g−1 after 1000 cycles at a current density of 2000 mA g−1. The imitating 1D coral‐like structural pattern is beneficial to alleviate the nanoparticle agglomeration and increase the contact area with the electrolyte, leading to the short diffusion path and facilitating the rapid transfer of lithium ions. The high‐level secondary nanobuilding blocks offer a large specific surface area, high surface‐to‐bulk ratio, and fast interfacial ion transport. Herein, it strongly sheds light on the elegant design concept of the hybrid for fabricating next‐generation advanced rechargeable LIBs.
Hubs disruption in mesial temporal lobe epilepsy. A resting‐state fMRI study on a language‐and‐memory network
Authors: Roger Elise , Pichat Cedric , Torlay Laurent , David Olivier , Renard Felix , Banjac Sonja , Attyé Arnaud , Minotti Lorella , Lamalle Laurent , Kahane Philippe , Baciu Monica
Published: November 2019

Mesial temporal lobe epilepsy (mTLE) affects the brain networks at several levels and patients suffering from mTLE experience cognitive impairment for language and memory. Considering the importance of language and memory reorganization in this condition, the present study explores changes of the embedded language‐and‐memory network (LMN) in terms of functional connectivity (FC) at rest, as measured with functional MRI. We also evaluate the cognitive efficiency of the reorganization, that is, whether or not the reorganizations support or allow the maintenance of optimal cognitive functioning despite the seizure‐related damage. Data from 37 patients presenting unifocal mTLE were analyzed and compared to 48 healthy volunteers in terms of LMN‐FC using two methods: pairwise correlations (region of interest [ROI]‐to‐ROI) and graph theory. The cognitive efficiency of the LMN‐FC reorganization was measured using correlations between FC parameters and language and memory scores. Our findings revealed a large perturbation of the LMN hubs in patients. We observed a hyperconnectivity of limbic areas near the dysfunctional hippocampus and mainly a hypoconnectivity for several cortical regions remote from the dysfunctional hippocampus. The loss of FC was more important in left mTLE (L‐mTLE) than in right (R‐mTLE) patients. The LMN‐FC reorganization may not be always compensatory and not always useful for patients as it may be associated with lower cognitive performance. We discuss the different connectivity patterns obtained and conclude that interpretation of FC changes in relation to neuropsychological scores is important to determine cognitive efficiency, suggesting the concept of “connectome” would gain to be associated with a “cognitome” concept.
Threshold Effects of Financial Sector Development on International Trade in Africa
Authors: Sare Yakubu Awudu
Published: November 2019

Earlier studies on threshold effects of financial sector development on international trade have relied on rudimentary approach which assumes exogenous inclusion of quadratic square terms of finance. However, findings from such studies are not instructive as it obscures country's unique domestic conditions such as differences in the levels of financial sector development. By relying on 46 countries in Africa over the period 1980–2016, this study employs a sample splitting and threshold estimation approach which allows finance–international trade to be mediated by the level of domestic financial sector development. We find evidence of threshold effects for a number of the countries suggesting that the precise impact of financial development on international trade is threshold–specific given the various indicators of finance. The study highlights that whether finance supports or limits international trade crucially depends on the attainment of a certain threshold which is both country and indicator–specific.
INCOSE Practitioners Challenge 2019: Clean Water and Sanitation in the Ganges River Basin
Authors: El‐Haloush Omar , Powley Stephen , Kaushik Yash , Flanigan David , Sitomer Joseph
Published: November 2019

During the INCOSE International Symposium 2019, INCOSE issued a Practitioners Challenge to address the problem of clean water and sanitation in the river Ganges basin in support of the broad focus INCOSE has placed on the topic of clean water and sanitation to tackle the National Academy of Engineering (NAE) Grand Challenges previously identified by the INCOSE Academic Council. The INCOSE Board chose to continue the Academic Council's work on the NAE Grand Challenges, focusing on Clean Water and Sanitation (CWS) and working to establish Memoranda of Understanding (MOUs) with organizations to provide systems expertise as appropriate. The United Nations’ (UN) may be one such organization with their focus on global Clean Water and Sanitation in their Sustainable Development Goal 6 (SDG 6). The team was asked to demonstrate the application of Systems Engineering principles and methods to explore solutions to achieve clean water for the inhabitants of the Ganges River basin.

After applying different systems engineering techniques and carrying out research, the team identified a multi‐facetted approach to addressing the clean water challenge, identifying key areas where systems engineering can be of benefit. Though this problem is, on the surface, one of technology and land use, it is set against the backdrop of arguably one of the most complex socio‐economic regions on the earth.

The need to address cultural aspects of the system and facilitate changes in human behavior, therefore, stands out as being particularly important in order to affect a successful outcome. Another key observation was that approaching and achieving the UN goals individually could lead to undesirable, unintended consequences due to strong interdependencies. This is an area where systems engineering could make a major contribution.
Size matters: Effect of granule size of the bone graft substitute (Herafill®) on bone healing using Masquelet's induced membrane in a critical size defect model in the rat's femur
Authors: Leiblein Maximilian , Koch Elias , Winkenbach Andreas , Schaible Alexander , Nau Christoph , Büchner Hubert , Schröder Katrin , Marzi Ingo , Henrich Dirk
Published: November 2019

The Masquelet technique for the treatment of large bone defects is a two‐stage procedure based on an induced membrane. The size of a scaffold is reported to be a critical factor for bone healing response. We therefore aimed to investigate the influence of the granule size of a bone graft substitute on bone marrow derived mononuclear cells (BMC) supported bone healing in combination with the induced membrane. We compared three different sizes of Herafill® granules (Heraeus Medical GmbH, Wehrheim) with or without BMC in vivo in a rat femoral critical size defect. A 10 mm defect was made in 126 rats and a membrane induced by a PMMA‐spacer. After 3 weeks, the spacer was taken out and membrane filled with different granule sizes. After 8 weeks femurs were taken for radiological, biomechanical, histological, and immunohistochemical analysis. Further, whole blood of the rat was incubated with granules and expression of 29 peptide mediators was assessed. Smallest granules showed significantly improved bone healing compared to larger granules, which however did not lead to an increased biomechanical stability in the defect zone. Small granules lead to an increased accumulation of macrophages in situ which could be assigned to the inflammatory subtype M1 by majority. Increased release of chemotactic respectively proangiogenic active factors in vitro compared to syngenic bone and beta‐TCP was observed. Granule size of the bone graft substitute Herafill® has significant impact on bone healing of a critical size defect in combination with Masquelet's technique in terms of bone formation and inflammatory potential.
Molecular epidemiology and virulence factors of methicillin‐resistant Staphylococcus aureus isolated from patients with bacteremia
Authors: Kim Hyun Jin , Choi Qute , Kwon Gye Cheol , Koo Sun Hoe
Published: November 2019

Background

The various virulence factors of methicillin‐resistant Staphylococcus aureus bacteremia (MRSAB) are associated with a high mortality rate worldwide. Further studies are warranted to confirm the significant relationship between the strains and virulence genes. Here, we prospectively investigated the molecular characteristics underlying the genotypes and virulence factors of MRSA isolated from patients with bacteremia.

Methods

We collected 59 MRSA isolates from adult patients with bacteremia. Antimicrobial susceptibility results were obtained with the Vitek2 automated system. Genotypes were identified with multi‐locus sequence typing (MLST) and pulse‐field gel electrophoresis (PFGE), and 21 virulence genes were detected with polymerase chain reaction (PCR).

Results

The 59 MRSA isolates mainly comprised ST5 (n = 31, 52.5%) and ST72 (n = 22, 37.2%). Most ST5 isolates and all ST72 isolates were clustered into one and two PFGE groups, respectively. The mean number of virulence genes was higher in ST5 than in ST72. Sel was more frequently detected in ST5 than in ST72, whereas sec and sed were found only in ST5. ST5 had significantly higher resistance against many antibiotics than ST72.

Conclusion

Most MRSA isolates causing bacteremia were ST5 (CC5) and ST72 (CC8), and those belonging to the same STs were divided into only a few PFGE groups. ST5 was associated with higher antibiotic resistance and staphylococcal superantigen toxin genes, than ST72, which may be related to its higher virulence.
A haplotype‐specific linkage disequilibrium pattern of monoamine oxidase A gene associated with regular smoking in women
Authors: Chiang Shang‐Lun , Nithiyanantham Srinivasan , Velmurugan Bharath Kumar , Tu Hung‐Pin , Lee Chien‐Hung , Ko Ying‐Chin
Published: November 2019

Background

Cigarette smoking in women is raising a public health problem. The X‐linked monoamine oxidase A (MAOA) was considered as a susceptibility gene to substance abuse of tobacco, but the evolutionary effect of MAOA may lead to a positive or negative association between genetic variations and smoking development among study regions.

Methods

Based on linkage disequilibrium (LD), we performed a haplotype‐based association to explore the effect of MAOA gene on women's smoking risk in a case‐control study.

Results

Genotyped single nucleotide polymorphisms (SNPs) of MAOA gene, rs5953210G>A, rs2283725A>G and rs1137070T>C, were significantly associated with current smoking risk in women, and the increased level of plasma MAO‐A activity was raised with per copy increment of risk allele in current smokers (P < .01). The haplotype patterns with minor haplotype frequency >.05 were constructed using the Expectation‐Maximization algorithm, and the haplotype‐specific A‐G‐C pattern raised the 2‐fold risk to develop regular smoking (P = .0005). In the diplotype analysis based on X‐inactivation mechanism relative to no and full dosage compensation, we showed that A‐G‐C haplotype not only increased regular smoking risk in a dose‐dependent manner (Ptrend = .0011) but also contributed to smoking risk in the dosage compensation mechanism. Compared to non‐smokers, the effect of A‐G‐C haplotype on random X‐activation was associated with the raised MAO‐A activity in women smokers (P < .05) although the lifetime cigarette consumption showed a difference that was not statistically significant.

Conclusion

This study provides information on MAOA LD‐based haplotype and diplotype patterns in women smoking.
Probing the changes of carotenoids in Microcystis flosaquae under environmental perturbations by two‐dimensional Raman correlation spectroscopy
Authors: He Shixuan , Xie Wanyi , Fang Shaoxi , Zhang Ping , Li Zhe , Zhou Daming , Zhang Yongna , Zhang Zhiyou , Guo Jinsong , Du Jinglei , Du Chunlei , Wang Deqiang
Published: November 2019

Raman mapping spectra of Microcystis flosaquae (M. flosaquae) subjected to environmental perturbations were used to study the correlations among the characteristics of M. flosaquae by two‐dimensional (2‐D) Raman correlation spectroscopy. Overlapping Raman characteristics of the carotenoids in M. flosaquae and their differences in algal growths were shown in the 2‐D synchronous and asynchronous correlation spectra. The asynchronous correlation Raman spectra demonstrated the accumulation of carotenoids in M. flosaquae under normal culture condition and environmental perturbations. High light flux obviously led to the accumulation of β‐carotene in M. flosaquae in comparison with normal culture condition. The results showed that 2‐D Raman correlation spectroscopy can be used to analyze the correlation of complex changes of the Raman characteristics of M. flosaquae induced by different environmental conditions to assess the accumulation of the carotenoids in algae and to predict the algal growth phases.
Amplitude and Phase Control of Guided Modes Excitation from a Single Dipole Source: Engineering Far‐ and Near‐Field Directionality
Authors: F. Picardi Michela , V. Zayats Anatoly , J. Rodríguez‐Fortuño Francisco
Published: November 2019

The design of far‐field radiation diagrams from combined electric and magnetic dipolar sources has recently found applications in nanophotonic metasurfaces that realize tailored reflection and refraction. Such dipolar sources also exhibit important near‐field evanescent coupling properties with applications in polarimetry and quantum optics. Here, a rigorous theoretical framework is introduced for engineering the angular spectra encompassing both far‐ and near‐fields of electric and magnetic sources and a unified description of both free space and guided mode directional radiation is developed. The approach uses the full parametric space of six complex‐valued components of magnetic and electric dipoles in order to engineer constructive or destructive near‐field interference. Such dipolar sources can be realized with dielectric or plasmonic nanoparticles. It is shown how a single dipolar source can be designed to achieve the selective coupling to multiple waveguide modes and far‐field simultaneously with a desired amplitude, phase, and direction.
Efficient and accurate spectral method for the time‐fractional dual‐phase‐lag heat transfer model and its parameter estimation
Authors: Zheng Rumeng , Jiang Xiaoyun , Zhang Hui
Published: November 2019

In the current paper, a heat transfer model is suggested based on a time‐fractional dual‐phase‐lag (DPL) model. We discuss the model in two parts, the direct problem and the inverse problem. Firstly, for solving it, the finite difference/Legendre spectral method is constructed. In the temporal direction, we employ the weighted and shifted Grünwald approximation, which can achieve second order convergence. In the spatial direction, the Legendre spectral method is used, it can obtain spectral accuracy. The stability and convergence are theoretically analyzed. For the inverse problem, the Bayesian method is used to construct an algorithm to estimate the four parameters for the model, namely, the time‐fractional order α, the time‐fractional order β, the delay time τT, and the relaxation time τq. Next, numerical experiments are provided to demonstrate the effectiveness of our scheme, with the values of τq and τT for processed meat employed. We also make a comparison with another method. The data obtained for the direct problem are used in the parameter estimation. The paper provides an accurate and efficient numerical method for the time‐fractional DPL model.
Intra‐session and inter‐subject variability of 3D‐FID‐MRSI using single‐echo volumetric EPI navigators at 3T
Authors: Moser Philipp , Eckstein Korbinian , Hingerl Lukas , Weber Michael , Motyka Stanislav , Strasser Bernhard , van der Kouwe Andre , Robinson Simon , Trattnig Siegfried , Bogner Wolfgang
Published: November 2019

Purpose

In this study, we demonstrate the first combination of 3D FID proton MRSI and spatial encoding via concentric‐ring trajectories (CRTs) at 3T. FID‐MRSI has many benefits including high detection sensitivity, in particular for J‐coupled metabolites (e.g., glutamate/glutamine). This makes it highly attractive, not only for clinical, but also for, potentially, functional MRSI. However, this requires excellent reliability and temporal stability. We have, therefore, augmented this 3D‐FID‐MRSI sequence with single‐echo, imaging‐based volumetric navigators (se‐vNavs) for real‐time motion/shim‐correction (SHMOCO), which is 2× quicker than the original double‐echo navigators (de‐vNavs), hence allowing more efficient integration also in short‐TR sequences.

Methods

The tracking accuracy (position and B0‐field) of our proposed se‐vNavs was compared to the original de‐vNavs in phantoms (rest and translation) and in vivo (voluntary head rotation). Finally, the intra‐session stability of a 5:40 min 3D‐FID‐MRSI scan was evaluated with SHMOCO and no correction (NOCO) in 5 resting subjects. Intra/inter‐subject coefficients of variation (CV) and intra‐class correlations (ICC) over the whole 3D volume and in selected regions of interest ROI were assessed.

Results

Phantom and in vivo scans showed highly consistent tracking performance for se‐vNavs compared to the original de‐vNavs, but lower frequency drift. Up to ~30% better intra‐subject CVs were obtained for SHMOCO (P < 0.05), with values of 9.3/6.9/6.5/7.8% over the full VOI for Glx/tNAA/tCho/m‐Ins ratios to tCr. ICCs were good‐to‐high (91% for Glx/tCr in motor cortex), whereas the inter‐subject variability was ~11–19%.

Conclusion

Real‐time motion/shim corrected 3D‐FID‐MRSI with time‐efficient CRT‐sampling at 3T allows reliable, high‐resolution metabolic imaging that is fast enough for clinical use and even, potentially, for functional MRSI.
Obesity, but not overweight, is associated with plantar light touch sensation in children aged 8 to 16 years: A cross‐sectional study
Authors: Ajisafe Toyin , Gilson Andrea , Garcia Theresa , DeAnda Noe
Published: November 2019

Objective

Increased foot‐ground contact loading engenders adaptive glabrous skin thickening and can decrease mechanoreceptor acuity and alter plantar cutaneous sensation. There has not been any research on whether overweight and obesity are similarly associated with normal plantar cutaneous sensation scores in children. This study investigated the associations between normal plantar cutaneous sensation scores and weight status (i.e., healthy weight, overweight, and obesity) in a sample of youth.

Methods

Plantar sensation was tested among 122 participants aged 8 to 16 years (10.3 ± 1.8 years; 140.0 ± 11.2 cm; 44.2 ± 16.0 kg) across the forefoot, midfoot, and rearfoot using Semmes‐Weinstein pressure aesthesiometry (0.07 g and 0.4 g monofilaments). Weight status was determined using the Centers for Disease Control and Prevention growth charts. Age‐ and sex‐adjusted models were used to explore the relationships between normal plantar sensation scores and weight status. Significant two‐tailed tests were set at p < .05.

Results

Only obesity was inversely associated with normal plantar sensation scores on the left (β = −.241; p = .009) and right (β = −.222; p = .018) forefeet, left (β = −.322; p = .001) and right (β = −.253; p = .007) midfeet, and left (β = −.286; p = .002) and right (β = −.228; p = .014) wholefeet (relative to healthy weight) when using the 0.07 g monofilament. There was no association between obesity and plantar sensation when using the 0.4 g monofilament.

Conclusions

Obesity is associated with diminished light touch plantar sensation. Considering previously reported higher mechanical loading and the fact that Merkel cells and the Aβfibers that innervate them are superficial to the hypodermis, adaptive glabrous skin thickening (rather than fat pad thickness) may underlie this association. Contrary to previous suggestions, overweight is not associated with decreased plantar cutaneous sensation.
Explanatory investigation of the moderating role of employee proactivity on the causal relationship between innovation‐based human resource management and employee satisfaction
Authors: Lasisi Taiwo T. , Eluwole Kayode K. , Ozturen Ali , Avci Turgay
Published: November 2019

In this paper, combinations of structural equation modeling and moderated‐hierarchical regression were used to examine the causal influence of organization‐driven innovation‐based human resource management on employee satisfaction among passenger‐contact employees in Nigeria. Further, we investigated the role that employee's proactivity plays in the aforementioned causal relationship. Specifically, our result implied that with higher levels of proactivity, passenger‐contact employees benefited more from the positive contribution of innovative human resource management than when proactivity is low. Theoretical and practical implications are suggested.
The importance of policy entrepreneurs in developing countries: A systematic review and future research agenda
Authors: Bakir Caner , Gunduz K. Aydin
Published: November 2019

How and with what effect policy entrepreneurship occurs is a persistent and intriguing question for scholars of public policy and administration and political science. So far, the main interest has been on policy entrepreneurship in developed countries rather than developing countries, which largely remains a black box. Adopting a systematic approach to reviewing the literature, this article aims to fill this void. It investigates when, why, and how policy and institutional reforms in developing countries take place, with special reference to the role of policy entrepreneurs. It reviews selected articles published in the Thomson Reuters Web of Knowledge Social Science Citation Index database from 1984 to 2018. It aims to show the current state of empirical and theoretical knowledge about policy entrepreneurship in developing countries and persistent knowledge gaps. The present review contributes to the body of knowledge on this topic in three main ways. First, we provide a comprehensive review of policy entrepreneurship in developing countries. Second, we consolidate existing research in the political science, public policy and administration, and politicial economy disciplines. Third, we establish connections between fragmented literatures, identify gaps between different research streams, and suggest promising paths for future research on policy entrepreneurship in developing countries.
Electro spun nanomats strengthened glass fiber hybrid composites: Improved mechanical properties using continuous nanofibers
Authors: Muthu Jacob S. D. , Bradely Philip , Jinasena Isuru I. K. , Wegner Leon D.
Published: November 2019

Hybrid multiscale fiber reinforced epoxy composite laminates were developed and characterized from woven glass fiber mats reinforced with nonwoven PAN nanofibers (diameters of 200 nm) produced via electrospinning. An electrospinning setup was designed and developed to produce continuous E‐spun nonwoven nanofiber (NWNF) mats, which were then used as interlaminar reinforcements for producing multiscale hybrid composites. A detailed study for producing E‐spun nanomats considering both solution and operation parameters was undertaken discussed and optimum spinning parameters were obtained. These parameters were used to produce the E‐spun NWNF mats, which were inserted into the interlaminar region of glass fiber reinforced epoxy laminates. The impact absorption energy, tensile strength, and flexural strength of the hybrid multiscale composites were found to increase with an increase in E‐spun NWNF mat weight fraction. These properties were compared to those of a conventional glass fiber composite laminates prepared from the neat epoxy resin with 32% glass fiber volume fraction. The effectiveness of the strengthening/toughening strategy formulated in this study indicates that the feasibility of using the E‐spun NWNF mat reinforcements for improving the mechanical properties of structured high‐performance composites. In addition, the present study provides motivation for the long‐term development of high‐strength high toughness bulk structural nanocomposites for broader engineering applications.
Effect of saline and alkaline solution aging on the properties of jute/poly(lactic acid) composites
Authors: Jiang Ning , Li Yaomin , Yu Tao , Pan Hongyu , Li Yan , Li Di
Published: November 2019

In this paper, jute/PLA composites were prepared by using twin‐screw extrusion, and injection molding with weight percent of jute fibers was 10%. A saline solution (pH = 7.48 ± 0.1) was prepared adding 0.05 g/mL of sodium chloride. A solution of NaOH with pH = 8.53 ± 0.1 was also prepared. Its water absorption, pH value, and mechanical properties were measured and differential scanning calorimetry, gel permeation chromatography, scanning electron microscopy were performed to analyze the aging mechanism of jute/PLA composite in saline and alkaline solution at 23°C. The results showed that the weight gain for jute/PLA composite immersed in alkaline solution was higher than that immersed in saline solution. The pH of alkaline solution declined faster than saline solution due to the neutralization of alkali and lactic acid, which produced from the hydrolysis of PLA. All the aged composites have a decline on mechanical properties in both solutions due to the degradation of jute fiber, PLA, and the interface between fiber and matrix. Mechanical strength of the composites under alkaline environment was lower than that of the composites under saline environment after aging.
An idealized numerical study of tropical cyclogenesis and evolution at the Equator
Authors: Kilroy Gerard , Smith Roger K. , Montgomery Michael T.
Published: November 2019

Tropical cyclone formation and evolution at, or near, the Equator is explored using idealized three‐dimensional model simulations, starting from a prescribed, initial, weak counterclockwise rotating vortex in an otherwise quiescent, nonrotating environment. Three simulations are carried out in which the maximum tangential wind speed (5 m s) is specified at an initial radius of 50, 100, or 150 km. After a period of gestation lasting between 30 and 60 hr, the vortices intensify rapidly, the evolution being similar to that for vortices away from the Equator. In particular, the larger the initial vortex size, the longer the gestation period, the larger the maximum intensity attained, and the longer the vortex lifetime. Beyond a few days, the vortices decay as the cyclonic vorticity source provided by the initial vortex is depleted and negative vorticity surrounding the vortex core is drawn inwards by the convectively driven overturning circulation. In these negative vorticity regions, the flow is inertially/centrifugally unstable. The vortex evolution during the mature and decay phases differs from that in simulations away from the Equator, where inertially unstable regions are much more limited in area. Vortex decay in the simulations appears to be related intimately to the development of inertial instability, which is accompanied by an outward‐propagating band of deep convection. The degree to which this band of deep convection is realistic is unknown.
Automatic peak assignment and visualisation of copolymer mass spectrometry data using the ‘genetic algorithm’
Authors: Town James S. , Gao Yuqui , Hancox Ellis , Liarou Evelina , Shegiwal Ataulla , Atkins Christophe J. , Haddleton David
Published: November 2019

Copolymer analysis is vitally important as the materials have a wide variety of applications due to their tunable properties. Processing mass spectrometry data for copolymer samples can be very complex due to the increase in the number of species when the polymer chains are formed by two or more monomeric units. In this paper, we describe the use of the genetic algorithm for automated peak assignment of copolymers synthesised by a variety of polymerisation methods. We find that in using this method we are able to easily assign copolymer spectra in a few minutes and visualise them into heat maps. These heat maps allow us to look qualitatively at the distribution of the chains, by showing how they alter with different polymerisation techniques, and by changing the initial copolymer composition. This methodology is simple to use and requires little user input, which makes it well suited for use by less expert users. The data outputted by the automatic assignment may also allow for more complex data processing in the future.
Functional process zones and their fish communities in temperate Andean river networks
Authors: Elgueta Anaysa , Thoms Martin C. , Górski Konrad , Díaz Gustavo , Habit Evelyn M.
Published: November 2019

Fluvial geomorphology provides an initial starting point for characterizing and understanding the ecogeomorphology of river networks. Knowledge of the spatial organization of morphological features and the way they influence processes within river networks is important for identifying potential links between the physical and ecological character of river systems. Here, a top‐down geographic information system‐based approach for determining the physical typology of river networks was used to determine and characterize the functional process zones (FPZs; large tracts of the river network with similar hydrogeomorphological character) of two rivers in central Chile. Seven distinct FPZs emerged from the analysis, and these had a nonuniform distribution along the river networks of the Biobío and Imperial Rivers. Some FPZs were frequent in number, with each FPZ segment being variable in length, whereas others were short and represented in limited number. A strong association between the physical character of FPZs and fish community was shown for the Biobío and Imperial Rivers. Specifically, dominant fish species varied among FPZs, and their habitat preferences were strongly related to the hydrogeomorphic character of the FPZ they dominated. These results are significant, as they can inform design of future ecological research and development of effective monitoring programmes.
Self‐Supportive Mesoporous Ni/Co/Fe Phosphosulfide Nanorods Derived from Novel Hydrothermal Electrodeposition as a Highly Efficient Electrocatalyst for Overall Water Splitting
Authors: Yao Mengqi , Hu Haohui , Sun Baolong , Wang Ni , Hu Wencheng , Komarneni Sridhar
Published: November 2019

Low cost and highly efficient bifuctional catalysts for overall water electrolysis have drawn considerable interests over the past several decades. Here, rationally synthesized mesoporous nanorods of nickel–cobalt–iron–sulfur–phosphorus composites are tightly self‐supported on Ni foam as a high‐performance, low cost, and stable bifunctional electrocatalyst for water electrolysis. The targeted designing and rational fabrication give rise to the nanorod‐like morphology with large surface area and excellent conductivity. The NiCoFe‐PS nanorod/NF can reach 10 mA cm−2 at a small overpotential of 195 mV with a Tafel slope of 40.3 mV dec−1 for the oxygen evolution reaction and 97.8 mV with 51.8 mV dec−1 for the hydrogen evolution reaction. Thus, this bifunctional catalyst shows low potentials of 1.52 and 1.76 V at 10 and 50 mA cm−2 toward overall water splitting with excellent stability for over 200 h, which are superior to most non‐noble metal‐based bifunctional electrocatalysts recently. This work provides a new strategy to fabricate multiple metal‐P/S composites with the mesoporous nanorod‐like structure as bifunctional catalysts for overall water splitting.
Standing Carbon‐Supported Trace Levels of Metal Derived from Covalent Organic Framework for Electrocatalysis
Authors: Xu Qing , Zhang Hao , Guo Yu , Qian Jing , Yang Shuai , Luo Dan , Gao Peng , Wu Dekun , Li Xiaopeng , Jiang Zheng , Sun Yuhan
Published: November 2019

Single atom catalysts (SACs) are receiving increasing interests due to their high theoretical catalytic efficiency and intriguing physiochemical properties. However, most of the synthetic methodologies involve high‐temperature treatment. This usually leads to limited control over the spatial distribution of metal sites and collapse of porous network that result in limited active site exposure. A strategy to construct SAC by using a covalent organic framework as the precursor is reported in this study. The as‐prepared catalyst is mainly composed of standing carbon layers with the presence of edge‐site hosted metal single atoms. Such structure configuration not only allows full site exposure but also endows the metal site with high intrinsic activity. With a trace amount of cobalt loading (0.17 wt%), the nanorice‐shaped catalyst displays promising electrochemical activities toward catalyzing the oxygen reduction reaction in both alkaline and acidic medium. An ultrahigh mass activity of 838 A gCo–1 at 0.9 V is achieved in the acidic electrolyte. This work suggests a new route to design SACs based on covalent organic framework for energy storage and conversion devices.
Simplified method for lateral‐torsional buckling of beams with lateral restraints
Authors: Beyer André , Bureau Alain
Published: November 2019

Selected, extended paper from the SDSS 2019 special session ECCS/TC8 – Structural Stability

This paper discusses the simplified method for the lateral‐torsional buckling design of I‐shaped beams with discrete lateral restraints. This popular method, also adopted in Eurocode 3, Part 1‐1:2005, consists of verifying the resistance of the compressed “flange” of the beam subjected to major‐axis bending. In this case the compressed flange is considered to be composed of the flange itself plus 1/3 of the compressed part of the web. This paper summarizes the analytical derivation of the simplified method and its key assumptions. It then presents inconsistencies arising if the simplified method is compared with the more generally applicable design methods for lateral‐torsional buckling given in Eurocode 3, Part 1‐1:2005. In addition, the design methods are compared with numerical simulations to reveal the lack of conservatism in the simplified method in some cases. The final part of the paper discusses how the simplified method may be modified in order to ensure a sufficient level of safety.