bluuebunny/crossref_metadata_2025_split huggingface dataset:
White matter biomarkers from fast protocols using axially symmetric diffusion kurtosis imaging
Authors: Hansen Brian , Khan Ahmad R. , Shemesh Noam , Lund Torben E. , Sangill Ryan , Eskildsen Simon F. , Østergaard Leif , Jespersen Sune N. 
Published: May 2017

White matter tract integrity (WMTI) can characterize brain microstructure in areas with highly aligned fiber bundles. Several WMTI biomarkers have now been validated against microscopy and provided promising results in studies of brain development and aging, as well as in a number of brain disorders. Currently, WMTI is mostly used in dedicated animal studies and clinical studies of slowly progressing diseases, and has not yet emerged as a routine clinical tool. To this end, a less data intensive experimental method would be beneficial by enabling high resolution validation studies, and ease clinical applications by speeding up data acquisition compared with typical diffusion kurtosis imaging (DKI) protocols utilized as part of WMTI imaging.Here, we evaluate WMTI based on recently introduced axially symmetric DKI, which has lower data demand than conventional DKI. We compare WMTI parameters derived from conventional DKI with those calculated analytically from axially symmetric DKI. We employ numerical simulations, as well as data from fixed rat spinal cord (one sample) and in vivo human (three subjects) and rat brain (four animals). Our analysis shows that analytical WMTI based on axially symmetric DKI with sparse data sets (19 images) produces WMTI metrics that correlate strongly with estimates based on traditional DKI data sets (60 images or more). We demonstrate the preclinical potential of the proposed WMTI technique in in vivo rat brain (300 μm isotropic resolution with whole brain coverage in a 1 h acquisition). WMTI parameter estimates are subject to a duality leading to two solution branches dependent on a sign choice, which is currently debated. Results from both of these branches are presented and discussed throughout our analysis. The proposed fast WMTI approach may be useful for preclinical research and e.g. clinical evaluation of patients with traumatic white matter injuries or symptoms of neurovascular or neuroinflammatory disorders.
Thermal and Sensitivity Study of Dihydroxyl Ammonium 5,5′‐Bistetrazole‐1,1′‐diolate (TKX‐50)‐based Melt Cast Explosive Formulations
Authors: Badgujar Dilip , Talawar Mahadev 
Published: May 2017

AbstractDihydroxyl ammonium 5,5′‐bistetrazole‐1,1′‐diolate (TKX‐50) is a promising energetic material with predicted performance similar to RDX as well as to CL‐20. In the present study, TKX‐50 was evaluated as a possible replacement for RDX in TNT‐based, aluminized as well as non‐aluminized melt cast formulations. Thermal analysis reveals the compatibility of TKX‐50 with benchmark explosives like RDX and TNT in explosive formulations. This paper describes the thermal and sensitivity study of TKX‐50 with RDX and TNT‐based melt cast explosives. The result indicated that TKX‐50 can be effectively used as a RDX replacement in melt cast explosive formulations. TKX‐50/TNT‐based aluminized composition shows more thermal stability than RDX/TNT based composition, which clearly indicated the usefulness of TKX‐50 in melt cast explosive formulations.
The structural flexibility of the human copper chaperone Atox1: Insights from combined pulsed EPR studies and computations
Authors: Levy Ariel R. , Turgeman Meital , Gevorkyan‐Aiapetov Lada , Ruthstein Sharon 
Published: May 2017

AbstractMetallochaperones are responsible for shuttling metal ions to target proteins. Thus, a metallochaperone's structure must be sufficiently flexible both to hold onto its ion while traversing the cytoplasm and to transfer the ion to or from a partner protein. Here, we sought to shed light on the structure of Atox1, a metallochaperone involved in the human copper regulation system. Atox1 shuttles copper ions from the main copper transporter, Ctr1, to the ATP7b transporter in the Golgi apparatus. Conventional biophysical tools such as X‐ray or NMR cannot always target the various conformational states of metallochaperones, owing to a requirement for crystallography or low sensitivity and resolution. Electron paramagnetic resonance (EPR) spectroscopy has recently emerged as a powerful tool for resolving biological reactions and mechanisms in solution. When coupled with computational methods, EPR with site‐directed spin labeling and nanoscale distance measurements can provide structural information on a protein or protein complex in solution. We use these methods to show that Atox1 can accommodate at least four different conformations in the apo state (unbound to copper), and two different conformations in the holo state (bound to copper). We also demonstrate that the structure of Atox1 in the holo form is more compact than in the apo form. Our data provide insight regarding the structural mechanisms through which Atox1 can fulfill its dual role of copper binding and transfer.
An adaptive degradation‐based maintenance model taking into account both imperfect adjustments and AGAN replacements
Authors: Letot Christophe , Dehombreux Pierre , Fleurquin Guillaume , Lesage Arnaud 
Published: May 2017

AbstractThis paper presents an adaptive maintenance model for equipment that can be adjusted (minor preventive maintenance, imperfect state) or replaced (major preventive maintenance, as good as new) at specific scheduled times based on degradation measurements. An initial reliability law that uses a degradation‐based model is built from the collection of hitting times of a failure threshold. Inspections are performed to update the reliability, the remaining useful life, and the optimum time for preventive maintenance. The case of both as good as new replacements and imperfect adjustments is considered. The proposed maintenance model is based on the optimization of the long‐term expected cost per unit of time. The model is then tested on a numerical case study to assess its effectiveness. This results in an improvement for the occurrences of maintenance tasks that minimizes the mean cost per unit of time as well as an optimized number of adjustments that can be considered before replacing an item. The practical application is a decision aid support to answer the 2 following questions: Should we intervene now or wait for the next inspection? For each intervention, should we adjust or replace the item of equipment? The originality is the presence of 2 criteria that help the maintainer to decide to postpone or not the preventive replacement time depending on the measured degradation and to decide whether the item should be adjusted or replaced.
Weighted‐average ℓ1 filtering for switched positive systems
Authors: Ren Yu , Sun Guanghui , Feng Zhiguang , Er Meng Joo , Wu Shiqian 
Published: May 2017

SummaryIn this paper, the filtering problem for a class of switched positive systems with dwell time is investigated. A novel weighted‐average technique is proposed for filter design such that the final estimate of the unmeasurable outputs of the considered system is more accurate than that of traditional approaches. The main contributions of this paper are summarized as follows: By exploiting the positivity and characteristics of switched positive systems with dwell time, a candidate linear copositive Lyapunov function, which is both quasi‐time‐dependent and mode‐dependent, is presented to establish the closed‐loop stability of the considered systems. Upon the established closed‐loop stability, less conservative bounded positive filters (both upper‐bound and lower‐bound filter) with ℓ1 disturbance attenuation performance are designed for the considered system. By introducing a proper weight, a weighted‐average approach, which is more general than the bounded filter design method, is proposed for filter design. The worst ℓ1 disturbance attenuation performance of the novel developed filter is evaluated. Both the bounded filters and the weighted‐average filter are designed by solving standard linear programming problems. A numerical example illustrates the effectiveness of the proposed approach. Copyright © 2017 John Wiley & Sons, Ltd.
Confronting the Digital Divide: Debunking Brave New World Discourses
Authors: Rowsell Jennifer , Morrell Ernest , Alvermann Donna E. 
Published: May 2017

AbstractThere is far more to the digital divide than meets the eye. In this article, the authors consolidate existing research on the digital divide to offer some tangible ways for educators to bridge the gap between the haves and have‐nots, or the cans and cannots. Drawing on Aldous Huxley's notion of a “brave new world,” some digital divide approaches and frameworks require debunking and are strongly associated with first‐world nations that fail to account for the differential access to technologies that people who live in poverty have. Taking a closer look at current realities, the authors send out a call to teachers, administrators, and researchers to think more seriously and consequentially about the effect the widespread adoption of technologies has had on younger generations and the role of the digital on knowledge creation and on imagined futures.
Dynamic enhancer function in the chromatin context
Authors: Goldstein Ido , Hager Gordon L. 
Published: May 2017

Enhancers serve as critical regulatory elements in higher eukaryotic cells. The characterization of enhancer function has evolved primarily from genome‐wide methodologies, including chromatin immunoprecipitation (ChIP‐seq), DNase‐I hypersensitivity (DNase‐seq), digital genomic footprinting (DGF), and the chromosome conformation capture techniques (3C, 4C, and Hi‐C). These population‐based assays average signals across millions of cells and lead to enhancer models characterized by static and sequential binding. More recently, fluorescent microscopy techniques, including fluorescence recovery after photobleaching, fluorescence correlation spectroscopy, and single molecule tracking (SMT), reveal a highly dynamic binding behavior for these factors in live cells. Furthermore, a refined analysis of genomic footprinting suggests that many transcription factors leave minimal or no footprints in chromatin, even when present and active in a given cell type. In this study, we review the implications of these new approaches for an accurate understanding of enhancer function in real time. In vivo SMT, in particular, has recently evolved as a promising methodology to probe enhancer function in live cells. Integration of findings from the many approaches now employed in the study of enhancer function suggest a highly dynamic view for the action of enhancer activating factors, viewed on a time scale of milliseconds to seconds, rather than minutes to hours. WIREs Syst Biol Med 2018, 10:e1390. doi: 10.1002/wsbm.1390This article is categorized under:

Analytical and Computational Methods > Computational Methods
Laboratory Methods and Technologies > Genetic/Genomic Methods
Laboratory Methods and Technologies > Imaging
Insights from the complete genome sequence of Clostridium tyrobutyricum provide a platform for biotechnological and industrial applications
Authors: Wu Qian , Liu Tingting , Zhu Liying , Huang He , Jiang Ling 
Published: May 2017

Abstract
Genetic research enables the evolution of novel biochemical reactions for the production of valuable chemicals from environmentally-friendly raw materials. However, the choice of appropriate microorganisms to support these reactions, which must have strong robustness and be capable of a significant product output, is a major difficulty. In the present study, the complete genome of the Clostridium tyrobutyricum strain CCTCC W428, a hydrogen- and butyric acid-producing bacterium with increased oxidative tolerance was analyzed. A total length of 3,011,209 bp of the C. tyrobutyricum genome with a GC content of 31.04% was assembled, and 3038 genes were discovered. Furthermore, a comparative clustering of proteins from C. tyrobutyricum CCTCC W428, C. acetobutylicum ATCC 824, and C. butyricum KNU-L09 was conducted. The results of genomic analysis indicate that butyric acid is produced by CCTCC W428 from butyryl-CoA through acetate reassimilation via CoA transferase, instead of the well-established phosphotransbutyrylase-butyrate kinase pathway. In addition, we identified ten proteins putatively involved in hydrogen production and 21 proteins associated with CRISPR systems, together with 358 ORFs related to ABC transporters and transcriptional regulators. Enzymes, such as oxidoreductases, HNH endonucleases, and catalase, were also found in this species. The genome sequence illustrates that C. tyrobutyricum has several desirable traits, and is expected to be suitable as a platform for the high-level production of bulk chemicals as well as bioenergy.
Impact of Armored Shorelines on Shore-Zone Fish Density in a Mid-Atlantic, USA, Estuary: Modulation by Hypoxia and Temperature
Authors: Balouskus Richard G. , Targett Timothy E. 
Published: May 2017

AbstractAnthropogenic modifications of estuarine environments, including shoreline hardening and corresponding alteration of water quality, are accelerating worldwide as human population increases in coastal regions. Estuarine fish species inhabiting temperate ecosystems are adapted to extreme variations in environmental conditions including water temperature, salinity, and dissolved oxygen across seasonal, daily, and hourly time scales. The present research utilized quantitative sampling to examine the spatiotemporal distribution of shore-zone estuarine fish species in association with four unique shoreline types across a range of water temperature and dissolved oxygen conditions. Fish were collected from the intertidal and shallow subtidal region of four shoreline types,Spartina alternifloramarsh,Phragmites australismarsh, riprap, and bulkhead, in the summer and fall of 2009 and 2010. Analyses were performed to (1) compare mean fish density among shoreline types across all water conditions and (2) explore relationships of the complete fish assemblage, three functional species groupings, and two fish species (Fundulus heteroclitusandMenidia menidia) to unique shoreline/water conditions. Significantly greater mean fish densities were found alongS. alterniflorashorelines than armored shorelines. Several metrics including fish density, species richness, and occurrence rates suggestS. alterniflorashorelines may serve as a form of refuge habitat during periods of low dissolved oxygen and high temperatures for various species, particularly littoral-demersal species includingF. heteroclitus. Potential mechanisms that could contribute to a habitat providing refuge during adverse water quality conditions include tempering of the adverse condition (decreased temperatures, increased dissolved oxygen), predation protection, and increased foraging opportunities.
Source Parameters of 1st April 2015 Chamoli Earthquake (Mw 4.8) vis-à-vis Seismotectonics of the Region
Authors: Verma Mithila , Sutar Anup K. , Bansal B. K. 
Published: May 2017

Abstract
The paper presents a detailed analysis of 1st April 2015 earthquake, whose epicenter (30.16° N, 79.28° E) was located near Simtoli village of Chamoli district, Uttarakhand. The focal depth is refined to 7 km by the grid search technique using moment tensor inversion. The source parameters of the earthquake as estimated by spectral analysis method suggested the source radius of ~1.0 km, seismic moment as 1.99E+23 dyne-cm with moment magnitude (Mw) of 4.8 and stress drop of 69 bar. The fault plane solution inferred using full waveform inversion indicated two nodal planes, the northeast dipping plane having strike 334° and dip 5° and the southwest dipping plane with dip 86° and strike 118°. The parallelism of the nodal plane striking 334° with dip 5° as indicated in depth cross sections of the tectonic elements suggested the north dipping Main Boundary Thrust (MBT) to be the causative fault for this earthquake. Spatio-temporal distribution of earthquakes during the period 1960-2015 showed seismic quiescence during 2006-2010 and migration of seismicity towards south.
A Natural Gamma Spectrometry Approach to Derive Clay Mineral Composition and Depositional Environment of a Reservoir Facies in Ramnad Sub-basin, Cauvery Basin, Southern India
Authors: Srikant D. , Shanmugam P. 
Published: May 2017

ABSTRACT
The Ramnad sub-basin is one of the most explored for hydrocarbons in Cauvery basin. A number of exploratory wells have been drilled to delineate hydrocarbon bearing horizons. Nannilam Formation of Santonian – Campanian age hosts considerable thickness of reservoir facies. The reservoir facies is mainly clastics such as sandstone and siltstone with lot of clay content. In addition to normal logs, the NGS (Natural Gamma Ray Spectrometry) logs are widely employed to estimate sediment composition and broad depositional environment of reservoir facies. The present study employs and analyses NGS logs of four well sections from Kanjirangudi area of Ramnad sub-basin to determine the clay mineral composition and depositional environment of Nannilam Formation. Thorium (Th), potassium (K) and uranium (U) concentrations and their interrelationships reveal that montmorillonite, illite and kaolinite are the dominant clay minerals. The clay mineral composition suggests that the sediments of the Nannilam Formation were derived from a provenance of acid igneous rocks during warm, humid and tropical conditions. Also, the ratios of Th/K indicate a deep open marine condition under which the sediments of the Nannilam Formation were deposited. These results would aid a better understanding and characterization of reservoir facies in the sub-basin.
Geochemical Characteristics of Tukureswari and Barbhita Granitoid in Goalpara District, Assam
Authors: Bhagabaty B. , Mazumdar M. K. , Mazumdar A. C. , Borah P. 
Published: May 2017

ABSTRACT
Late intrusive Tukureswari granitoids (TKG) and the Barbhita granitoids (BBG) of Goalpara district in western Assam constitute an important component of the continental crust of the Shillong Plateau. Thus, the geochemical study of these two granitoids involving their origin, classification and petrogenetic significance would be a contribution towards a better understanding of the evolution of continental crust of the Shillong Plateau.
The major oxide and trace element geochemistry reveals several genetic issues on these two granitoids. The I-type affinity of the TKG is indicated from the geochemical features such as high TiO2, P2O5 and K2O contents, low normative corundum (&lt; 1%), high Na2O/K2O ratios, and low concentrations of Ni, Co and Cr. Further, enriched LREE-LILE and HFSE depletion, as well as the normal calc-alkaline nature of arc affinity (e.g., enhanced LILE abundance and low HFSE/LILE ratios) of the TKG indicate subduction-related magmatism. The TKG are also categorized as a deep-level pluton, being enriched in LREE and depleted in total REE and HFSE (Y, Nb, Ta, Zr, Hf). The high La/Nb ratio (1.9 – 8.6), negative Nb and Ti anomalies also suggest orogenic related magmatism.
On the other hand, the geochemistry of the BBG reveal a high Niggli Si and Mg values, slightly high normative corundum values (2.16 – 3.41), high Th/Ta, Y/Nb, La/Nb, K2O/Na2O, and Rb/Sr ratios. It also shows ASI, K, Rb, and U contents, prominent depletion of Nb, Sr and Ti on the primitive mantle-normalized multi-element spider diagrams and a low concentrations of Cu, Cr, V and Na2O (&gt; 3.2%). All these geochemical characteristics provide strong evidences in support of a sedimentary parentage for Barbhita granitoids (BBG) and are dominantly of S-type.
SMR and Kinematic Analysis for Slope Instability along Bodi-Bodimettu Ghat section, Tamil Nadu
Authors: Saranaathan S. E. , Kannan M. 
Published: May 2017

ABSTRACT
This study evaluates slope stability of 19km stretch Bodimettu ghat section, Theni, Tamil Nadu. The study involves 107.8km to 117.5km stretch by dividing it into two zones - Kaththuparai and Bodimettu slope. These two sections are considered for slope stability studies. In this study, analysis of the rock slope stability was performed using Modified SMR technique. Hoek and Bray (1981) analysis have been used for rock cut slopes. 12 rock slopes were identified in Kaththuparai section and four slopes in Bodimettu section. The detailed field investigations were carried out to collect data required for RMR and SMR calculation and SMR was calculated for each section. As per Hoek and Bray (1981) stereographic projection methods, FOS was calculated. In this study, sections R1 and R2 fulfill wedge conditions and R1, R2, R5, R7, R9, R10, R11, R12, R13, R14 and R16 are suitable for planar and stereographic analysis. The details are furnished in this paper. The planar analysis shows that, FOS for the sections R2/J2, R5, R9, R10, and R11/J3 was &lt; 1, and stereographic projection study shows that sections R2, R5, R7, R9, R10, R11/J3 and R13 are present in unstable zone.
Family history and TOMM40 '523 interactive associations with memory in middle‐aged and Alzheimer's disease cohorts
Authors: Willette Auriel A. , Webb Joseph L. , Lutz Michael W. , Bendlin Barbara B. , Wennberg Alexandra M. , Oh Jennifer M. , Roses Allen , Koscik Rebecca L. , Hermann Bruce P. , Dowling N. Maritza , Asthana Sanjay , Johnson Sterling C. 
Published: May 2017

AbstractIntroductionFamily history (FH) of Alzheimer's disease (AD) affects mitochondrial function and may modulate effects of translocase of the outer mitochondrial membrane 40 kDa (TOMM40) rs10524523 ('523) poly‐T length on memory decline.MethodsFor 912 nonapolipoprotein ε4 middle‐aged adults and 365 aged adults across the AD spectrum, linear mixed models gauged FH and TOMM40 '523 interactions on memory and global cognition between baseline and up to 10 years later. A cerebrospinal fluid mitochondrial function biomarker was also assessed.ResultsFor FH negative participants, gene‐dose preservation of memory and global cognition was seen for “very long” versus “short” carriers. For FH positive, an opposite gene‐dose decline was seen for very long versus short carriers. Maternal FH was a stronger predictor in aged, but not middle‐aged, participants. Similar gene‐dose effects were seen for the mitochondrial biomarker aspartate aminotransferase.DiscussionThese results may clarify conflicting findings on TOMM40 poly‐T length and AD‐related decline.
An improved envelope detection method using particle swarm optimisation for rolling element bearing fault diagnosis
Authors: Tyagi Sunil , Panigrahi S.K. 
Published: May 2017

Abstract
Traditionally Envelope Detection (ED) is implemented for detection of rolling element bearing faults by extracting the envelope of band-passed vibration signal and thereafter taking its Fourier transform. The performance of ED is highly sensitive to the envelope window (i.e. central frequency and bandwidth of the passband). This paper employs Particle Swarm Optimisation (PSO) to select the most optimum envelope window to band pass the vibration signals emanating from rotating driveline that was run in normal and with faults induced rolling element bearings. The envelopes of band-passed signals were extracted with the help of Hilbert Transform. The performance of ED whose envelope window was optimised by PSO to identify various commonly occurring bearing faults such as bearing with Outer Race Fault (ORF), Inner Race Fault (IRF) and Rolling Element Fault (REF) were checked under varying load conditions. The performance of ‘ED enhanced by PSO’ was also checked with increase in the severity of defect. It was shown that the improved ED method is successfully able to identify all types of bearing faults under different load conditions. It was shown that the by selecting envelope window by PSO makes ED especially useful to identify bearing faults at the incipient stage of defect. It was also shown by presenting comparative performance that by optimising the envelope window by PSO the performance of ED gets significantly enhanced in comparison to the traditional ED method for bearing fault diagnosis.