bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diffusion tensor imaging and disability progression in multiple sclerosis: A 4‐year follow‐up study
Authors: Kolasa Marcin , Hakulinen Ullamari , Brander Antti , Hagman Sanna , Dastidar Prasun , Elovaara Irina , Sumelahti Marja‐Liisa 
Published: December 2018

AbstractObjectivesDiffusion tensor imaging (DTI) is sensitive technique to detect widespread changes in water diffusivity in the normal‐appearing white matter (NAWM) that appears unaffected in conventional magnetic resonance imaging. We aimed to investigate the prognostic value and stability of DTI indices in the NAWM of the brain in an assessment of disability progression in patients with a relapsing‐onset multiple sclerosis (MS).MethodsForty‐six MS patients were studied for DTI indices (fractional anisotropy (FA), mean diffusivity (MD), radial (RD), and axial (AD) diffusivity) in the NAWM of the corpus callosum (CC) and the internal capsule at baseline and at 1 year after. DTI analysis for 10 healthy controls was also performed at baseline. Simultaneously, focal brain lesion volume and atrophy measurements were done at baseline for MS patients. Associations between DTI indices, volumetric measurements, and disability progression over 4 years were studied by multivariate logistic regression analysis.ResultsAt baseline, most DTI metrics differed significantly between MS patients and healthy controls. There was tendency for associations between baseline DTI indices in the CC and disability progression (p < 0.05). Changes in DTI indices over 1 year were observed only in the CC (p < 0.008), and those changes were not found to predict clinical worsening over 4 years. Clear‐cut association with disability progression was not detected for baseline volumetric measurements.ConclusionAberrant diffusivity measures in the NAWM of the CC may provide additional information for individual disability progression over 4 years in MS with the relapsing‐onset disease. CC may be a good target for DTI measurements in monitoring disease activity in MS, and more studies are needed to assess the related prognostic potential.
Perilesional and homotopic area activation during proverb comprehension after stroke
Authors: Yi You Gyoung , Kim Dae Yul , Shim Woo Hyun , Oh Joo Young , Kim Ho Sung , Jung Minji 
Published: December 2018

AbstractIntroductionThe mechanism of functional recovery in right hemisphere (RH) stroke patients when attempting to comprehend a proverb has not been identified. We previously reported that there is bilateral hemisphere involvement during proverb comprehension in the normal population. However, the underlying mechanisms of proverb comprehension following a right middle cerebral artery (MCA) infarction have not yet been fully elucidated.MethodsWe here compared the brain regions activated by literal sentences and by opaque or transparent proverbs in right MCA infarction patients using functional magnetic resonance imaging (fMRI). Experimental stimuli included 18 opaque proverbs, 18 transparent proverbs, and 18 literal sentences that were presented pseudorandomly in 1 of 3 predesigned sequences.ResultsFifteen normal adults and 17 right MCA infarction patients participated in this study. The areas of the brain in the stroke patients involved in understanding a proverb compared with a literal sentence included the right middle frontal gyrus (MFG) and frontal pole, right anterior cingulate gyrus/paracingulate gyrus and left inferior frontal gyrus (IFG), middle temporal gyrus (MTG), precuneus, and supramarginal gyrus (SMG). When the proverbs were presented to these stroke patients in the comprehension tests, the left supramarginal, postcentral gyrus, and right paracingulate gyrus were activated for the opaque proverbs compared to the transparent proverbs.ConclusionsThese findings suggest that the functional recovery of language in stroke patients can be explained by perilesional activation, which is thought to arise from the regulation of the excitatory and inhibitory neurotransmitter system, and by homotopic area activation which has been characterized by decreased transcallosal inhibition and astrocyte involvement.
Synthetic Biology: Engineering Mammalian Cells To Control Cell‐to‐Cell Communication at Will
Authors: Kojima Ryosuke , Fussenegger Martin 
Published: December 2018

AbstractCell‐to‐cell communication plays a key role in the regulation of many natural biological processes. Recent advances in mammalian synthetic biology are making it possible to rationally engineer cell‐to‐cell communication for therapeutic and other purposes. Here, we review state‐of‐the‐art engineering principles to control cell‐to‐cell communication, focusing on communication between mammalian cells with diffusible factors (e.g., small molecules or exosomes) or direct cell contact, and on interkingdom communication between mammalian cells and bacteria. Potential applications include construction of artificial tissues able to perform complex computations, sophisticated cell‐based cancer therapies, use of mammalian cells as a new class of cargo delivery modality, development of design principles to control pattern formation of cell populations, and treatment of infectious diseases. We also discuss the challenges facing practical applications, and possible enabling technologies to overcome them.
Facile in situ Encapsulation of Highly Dispersed Ni@MCM‐41 for the Trans‐Decalin Production from Hydrogenation of Naphthalene at Low Temperature
Authors: Song Xiaoyun , Guan Qingxin , Shu Yu , Zhang Xiaojing , Li Wei 
Published: December 2018

AbstractNi@MCM‐41 catalyst that has uniformly distributed, highly dispersed Ni nanoparticles (about 2.3 nm) was designed and successfully synthesized by in situ encapsulation of Ni in the channels of MCM‐41. This catalyst exhibits excellent thermal stability and hydrogenation activity. Water insoluble nickel acetylacetonate (Ni(acac)2) was first dissolved aqueous solution of cetyltrimethyl ammonium bromide (CTAB) and encapsulated in micelles of CTAB. Sodium silicate was used as a silicon source to rapidly hydrolyze and then wrap on the micelle surface to synthesize the MCM‐41 zeolite. The MCM‐41 zeolite encapsulating Ni(acac)2 was synthesized within a short time (4 h) at 120 °C. Compared with conventional supported catalysts, thus 3 wt.% Ni@MCM‐41 has ultra‐small uniformly distributed Ni nanoparticles and exhibits improved activity for the hydrogenation of naphthalene to decalin at very low reaction temperatures. The TOF and the apparent activation energy of Ni@MCM‐41 and the conventional catalysts (Ni/MCM‐41 and Pt/MCM‐41) were evaluated and compared. And the catalysis mechanism was analyzed. Furthermore, this Ni@MCM‐41 catalyst offers an additional advantage of selectivity in decalin isomerization; 92 % trans‐decalin selectivity was achieved at a wide temperature range.
Facile Synthesis of a High Performance NiPd@CMK‐3 Nanocatalyst for Mild Suzuki‐Miyaura Coupling Reactions
Authors: Park Ji Chan , Kim Aram , Jang Sanha , Yang Jung‐Il , Kang Shin Wook , Lee Chan‐Woo , Kim Byung‐Hyun , Park Kang Hyun 
Published: December 2018

AbstractHighly dispersed nickel‐palladium bimetallic nanoparticles (∼2 nm) on ordered mesoporous carbon CMK‐3 (NiPd@CMK‐3) were simply prepared using a co‐infiltration method of the metal salts. The nanoparticles were successfully applied to the mild Suzuki‐Miyaura coupling reactions at 25∼50 °C using 4‐bromoanisole and phenylboronic acid, and showed excellent catalytic performance with the high activity (0.521×10−3 molc ⋅ gam−1 ⋅ s−1) and productivity (69.1 gp ⋅ gcat−1 ⋅ h−1).
Modified Graphene Oxide Based Zinc Composite: an Efficient Catalyst for N‐formylation and Carbamate Formation Reactions Through CO2 Fixation
Authors: Khatun Resmin , Biswas Surajit , Islam Sarikul , Biswas Imdadul Haque , Riyajuddin Sk , Ghosh Kaushik , Islam Sk Manirul 
Published: December 2018

AbstractCatalytic fixation of CO2 through chemical reactions is always a challenging task of synthetic chemistry. This paper represents the design and synthesis of an eco‐friendly low cost zinc metal containing heterogeneous catalyst of aminically modified Graphene Oxide. Characterization of the catalyst has been carried out by Raman and FTIR spectra, AAS, XRD, TEM, SEM, EDX and N2 adsorption desorption studies. It was found that the catalyst was very proficient for the CO2 fixation through N‐formylation and carbamate formation reactions of amines. Catalytic N‐formylation reaction of both aromatic and aliphatic amines gave high yield of corresponding formylated products in presence of polymethylhydrosiloxane (PMHS) as reducing agent under 1 bar CO2 pressure and mild temperature. Formation of carbamates from aniline or its derivatives and alkyl/aryl bromide with good product selectivity was also achieved under same CO2 pressure in presence of our synthesized catalyst at room temperature with solvent‐free condition. The catalyst is reusable and eﬃcient even after six cycles.
Bimetal/Metal Oxide Encapsulated in Graphitic Nitrogen Doped Mesoporous Carbon Networks for Enhanced Oxygen Electrocatalysis
Authors: Jose Vishal , Jayakumar Anjali , Lee Jong‐Min 
Published: December 2018

AbstractIn this study, Fe doped, Co and CoO encapsulated N doped carbon frameworks were prepared from simple hybrid zeolite imidazole frameworks (ZIF) with extra N enrichment. The facile strategy included preparation of ZIF‐8 core and ZIF‐67 shell and later replacing the metal centers of ZIF with Fe ions and increasing the N content with N rich melamine. The metal and metal oxide components got captured and encapsulated in the N doped mesoporous carbon frameworks through a pyrolysis process at different temperatures. Fe, Co and CoO were trapped in the N doped mesoporous carbon networks through annealing and denoted as FCNCx. The activity and electrochemical stability of such prepared materials towards ORR and OER were tested in basic media. After analyzing rotating disk electrode studies, FCNC900 was seen to perform superior bifunctional electrocatalytic performance for both ORR and OER which was higher than Pt/C catalyst. Promising ORR performance of FCNC900 can be simply be judged from E1/2=0.868 V (vs. RHE) and Eonset=1.01 V (vs. RHE) while OER overpotential for same catalyst was 360 mV much smaller than others. Longer stability and high methanol tolerance of this catalyst was also investigated.
Pseudocapacitive Graphene‐Wrapped Porous VO2 Microspheres for Ultrastable and Ultrahigh‐Rate Sodium‐Ion Storage
Authors: Zhao Luzi , Wei Qiulong , Huang Yongxin , Luo Rui , Xie Man , Li Li , Mai Liqiang , Wu Feng , Chen Renjie 
Published: December 2018

AbstractThe exploration of anode materials with enhanced electronic/ionic conductivity and structural stability is beneficial for the development of sodium‐ion batteries. Herein, a simple solution‐derived method is demonstrated to fabricate porous VO2 microsphere composite with a graphene‐wrapped structure (VO2/G). When used as the anode material for sodium‐ion batteries, the VO2/G electrode delivers a high reversible specific capacity (373.0 mAh g−1), great rate capability (138.8 mA h g−1 at 24.0 A g−1, ≈21 s per charge/discharge), and excellent long‐cycling performance (95.9 % capacity retention for 3600 cycles at 2.0 A g−1). The outstanding electrochemical property of VO2/G is mainly attributed to its unique graphene‐wrapped porous structure and the pseudocapacitive‐dominated feature. In addition, the sodium‐ion storage mechanism of VO2/G is investigated by various ex‐situ characterization techniques. During the first sodiation process, the sodium‐ion appears to partially reduce VO2/G and form metallic vanadium, sodium oxide, and amorphous sodium vanadium. This work provides new fundamental information for the design and application of vanadium oxides for energy storage system.
Single‐Phase Cu3SnS4 Nanoparticles for Robust High Capacity Lithium‐Ion Battery Anodes
Authors: Sharma Neha , Phase Deodatta , Thotiyl Musthafa Ottakam , Ogale Satishchandra 
Published: December 2018

AbstractWith the evolution of Li‐ion batteries, they have been employed in many applications. However, high energy density and power density batteries are yet to be developed to meet the necessities at the application end. Sulfides are a good choice as anode material as they show a much higher specific capacity than conventional graphite anodes. But unfortunately, sulfide dissolution and polysulfide shuttling are big drawbacks for their operation. Herein, single phase ternary metal sulfide Cu3SnS4 (CTS) nanoparticles are synthesized with high Cu : Sn ratio and examined for application as Li‐ion battery anode. High specific capacities of 1082 mAh g−1 at 0.2 A g−1 and 440 mAh g−1 at a high rate of 3 A g−1 are realized with superior stability tested up to 950 cycles. Utilizing the CTS NPs can minimize the polysulfide dissolution. The high Cu : Sn ratio provides excess Cu atoms as the buffer matrix for volume expansion of Sn, leading to high stability and specific capacity. Compared to other reported Cu based mixed phase or composite ternary sulfide materials, the CTS NPs presented herein show a better performance. In a full cell device using LiCoO2 (LCO) as cathode, a good performance is achieved as well with an energy density of 405 Wh/Kg at 0.1 A g−1.
Quantitative Assessment of the Effect of Chronic Kidney Disease on the Nonrenal Clearance of 10 Drugs After Intravenous Administration
Authors: Hinderling Peter H. , Yu Yichao 
Published: December 2018

AbstractThe investigation identified 10 publications that reported the individual values of total clearance (CL), renal clearance (CLr), nonrenal clearance (CLnr), and the glomerular filtration rate (GFR), in subjects with varying renal functions. We used these data to estimate extent and prevalence of changes in CLnr in chronic kidney disease (CKD) by examining the relationship between clearances and renal function. The investigation was restricted to drugs given intravenously and eliminated by mixed renal and nonrenal pathways. Six drugs showed a significant reduction of CLnr of 61% to 63% in subjects with severe renal impairment, suggesting that the decline of CLnr in advanced CKD can be clinically relevant and may not be uncommon. The decline of CLnr in CKD for these 6 drugs is linearly correlated with the decline of CLr. With 4 of the drugs studied, a significant reduction of CLnr in CKD was not seen. Renal clearance is a more reliable measure of renal function than GFR assessed by creatinine clearance. Chronic kidney disease affects the elimination more than the distribution of the 10 drugs.
Mobile delay‐tolerant networks with energy‐harvesting and wireless energy transfer cooperation
Authors: Ait Oualhaj Omar , Kobbane Abdellatif , Ben‐Othman Jalel 
Published: December 2018

SummaryWe consider a mobile delay‐tolerant networks (MDTNs) with energy‐harvesting capabilities. In order to determine energy management policies that will improve network capacity and packet delivery ratio and maximize the system throughput, we consider a source node that seeks to send packets to a destination node. The optimal policy for the source varies according to its system state, which allows it to guarantee a maximum delivery probability rate. Our problem is modeled by decision theory; as a start, we are interested in the MDP to model and solve such sequential decision problems. Our goal is to optimize for each node, a utility depending on a random environment and decisions made by the node. As the MDP formalism reaches its limits when it is necessary to take into account the interactions between different several nodes, we will start using the graph‐based MDP where the state and action spaces are factorizable by variables. The transition functions and rewards are then decomposed into local functions and the dependency relations between the nodes are represented by a graph. To calculate the optimal policy, we propose Mean Field Approximation (MFA) and Approximate linear‐programming (ALP) algorithms for solving GMDP problem.
Comparative study of stress characteristics in surrounding bone during insertion of dental implants of three different thread designs: A three‐dimensional dynamic finite element study
Authors: Udomsawat Chaiwat , Rungsiyakull Pimduen , Rungsiyakull Chaiy , Khongkhunthian Pathawee 
Published: December 2018

AbstractThe objective of this study is to evaluate the stress distribution characteristics around three different dental implant designs during insertion into bone, using dynamic finite element stress analysis. Dental implant placement was simulated using finite element models. Three implants with different thread and body designs (Model 1: root form implant with three different thread shapes; Model 2: tapered implant with a double‐lead thread; and Model 3: conical tapered implant with a constant buttress thread) were assigned to insert into prepared bone cavity models until completely placed. Stress and strain distributions were descriptively analyzed. The von Mises stresses within the surrounding bone were measured. At the first 4‐mm depth of implant insertion, maximum stress within cortical bone for Model 3 (175 MPa) was less than the other models (180 MPa each). Stress values and concentration area were increasing whereas insertion depth increased. At full implant insertion depth, maximum stress level in Model 1 (35 MPa) within the cancellous bone was slightly greater than in Models 2 (30 MPa) and 3 (25 MPa), respectively. Generally, for all simulations, the highest stress value and the location of the stress concentration area were mostly in cortical bone. However, the stress distribution patterns during the insertion process were different between the models depending on the different designs geometry that contacted the surrounding bone. Different implant designs affect different stress generation patterns during implant insertion. A range of stress magnitude, generated in the surrounding bone, may influence bone healing around dental implants and final implant stability.
A Stackelberg game for relay selection and power allocation in an active cooperative model involving primary users and secondary users
Authors: Ghanem Montajab , Sabaei Masoud , Dehghan Mehdi 
Published: December 2018

SummaryIn recent years, cooperative communications have been widely used to improve the spectrum efficiency in cognitive radio networks. In this paper, we propose a new cooperative model involving primary and secondary users, where a primary transmitter may select a number of the secondary users to act as relays in order to maximize its data rate and to transmit at lower energy level, thereby saving energy and reducing interference at the secondary base station. The cooperative transmission is a multiple two‐hop relaying scheme, which guarantees an achievable data rate exceeding that in the direct transmission. In the proposed approach, the problem of joint relay selection and power allocation is formulated as a Stackelberg game, which converges to a unique optimal Nash equilibrium. Performance evaluation shows that this model offers benefit to both sides, where the primary users achieve higher data rate at lower energy consumption and the signal to interference plus noise ratio at the secondary base station is increased significantly. In addition, the results show that the proposed solution outperforms the investigated models in terms of achievable data rate.
The relationship between menopausal women infected with the human immunodeficiency virus and cervical atrophy: A cytologic study
Authors: Davies Gillian , Firnhaber Cynthia , Pantanowitz Liron , Michelow Pamela 
Published: December 2018

BackgroundWith the advent of combined antiretroviral therapy (cART), HIV positive women are expected to live longer. The effect of chronic HIV infection and cART on cervical epithelial maturation has not been well studied in postmenopausal woman. The objective of this study was to determine whether HIV positive postmenopausal women on cART show expected atrophic changes in cervical Pap tests.MethodsThe maturation index (MI) was performed on routine cervical smears from HIV‐infected, postmenopausal women attending an HIV clinic in a tertiary hospital in Johannesburg, over a 4‐year period from January 2009 to December 2012.ResultsIn Pap smears of 111 patients on cART, 58 (52%) showed an unexpected predominantly mature squamous epithelial pattern whereas 53 (48%) were predominantly immature or atrophic (P = .0001). There was no significant statistical difference in maturation according to cART use.ConclusionHIV‐infected, postmenopausal women in this study had reduced rates of cervical atrophy than expected, irrespective of cART use and CD4 count. Initiation of cART before menopause was associated with greater cervical epithelium maturation than those women who started cART after menopause. Additional, larger studies are required to confirm this novel finding and to investigate the reason for this phenomenon.
Noninvasive sampling reveals population genetic structure in the Royle’s pika, Ochotona roylei, in the western Himalaya
Authors: Bhattacharyya Sabuj , Ishtiaq Farah 
Published: December 2018

AbstractUnderstanding population genetic structure of climate‐sensitive herbivore species is important as it provides useful insights on how shifts in environmental conditions can alter their distribution and abundance. Herbivore responses to the environment can have a strong indirect cascading effect on community structure. This is particularly important for Royle's pika (Lagomorpha: Ochotona roylei), a herbivorous talus‐dwelling species in alpine ecosystem, which forms a major prey base for many carnivores in the Himalayan arc. In this study, we used seven polymorphic microsatellite loci to detect evidence for recent changes in genetic diversity and population structure in Royle's pika across five locations sampled between 8 and 160 km apart in the western Himalaya. Using four clustering approaches, we found the presence of significant contemporary genetic structure in Royle's pika populations. The detected genetic structure could be primarily attributed to the landscape features in alpine habitat (e.g., wide lowland valleys, rivers) that may act as semipermeable barriers to gene flow and distribution of food plants, which are key determinants in spatial distribution of herbivores. Pika showed low inbreeding coefficients (FIS) and a high level of pairwise relatedness for individuals within 1 km suggesting low dispersal abilities of talus‐dwelling pikas. We have found evidence of a recent population bottleneck, possibly due to effects of environmental disturbances (e.g., snow melting patterns or thermal stress). Our results reveal significant evidence of isolation by distance in genetic differentiation (FST range = 0.04–0.19). This is the first population genetics study on Royle's pika, which helps to address evolutionary consequences of climate change which are expected to significantly affect the distribution and population dynamics in this talus‐dwelling species.