bluuebunny/crossref_metadata_2025_split huggingface dataset:
The impact of pre‐existing peripheral artery disease on transcatheter aortic valve implantation outcomes: A systematic review and meta‐analysis
Authors: Ueshima Daisuke , Barioli Alberto , Nai Fovino Luca , D'Amico Gianpiero , Fabris Tommaso , Brener Sorin J. , Tarantini Giuseppe 
Published: May 2019

AbstractBackgroundPeripheral arterial disease (PAD) plays a decisive role in the preinterventional selection process of the optimal vascular access site in patients undergoing transcatheter aortic valve implantation (TAVI). However, the impact of PAD on mortality and vascular complications (VCs) in TAVI‐treated patients remains unclear. Accordingly, we aimed to assess the outcomes of patients with and without PAD undergoing TAVI, by performing a meta‐regression analysis.MethodsStudies published between January 2002 and March 2018 and reporting outcomes according to the presence of PAD in TAVI patients were identified. Outcome measures analyzed were short‐, mid‐ and long‐term mortality, and peri‐procedural VC. The interaction between sheath size and PAD on outcomes was also assessed.ResultsA total of 26 studies (68,581 TAVI patients, of whom 17,326 with preprocedural PAD) were included in the analysis. Patients with PAD had higher risk of mortality at short‐ (HR 1.36, 95% confidence interval [CI] 1.13‐1.63, p = .0009), mid‐ (HR 1.18, 95% CI 1.08‐1.30, p = .0005), and long‐term (HR 1.36, 95% CI 1.24‐1.48, p < .0001) follow‐up, and higher risk of VC (RR 1.55, 95% CI 1.27; 1.89, p < .0001). Moreover, the adoption of smaller sheaths during TAVI procedures was associated with fewer VC both in PAD and non‐PAD patients, but the latter group had a more pronounced benefit.ConclusionsPatients with pre‐existent PAD are at increased risk of all‐cause mortality and VC after TAVI. The adoption of smaller sheaths during the procedure seems to be associated with fewer peri‐procedural VC both in PAD and non‐PAD patients.
Two‐Dimensional SnSe2/CNTs Hybrid Nanostructures as Anode Materials for High‐Performance Lithium‐Ion Batteries
Authors: Chen Hongwen , Jia Bei‐Er , Lu Xinsheng , Guo Yichuan , Hu Rui , Khatoon Rabia , Jiao Lei , Leng Jianxing , Zhang Liqiang , Lu Jianguo 
Published: May 2019

AbstractTin diselenide (SnSe2), as an anode material, has outstanding potential for use in advanced lithium‐ion batteries. However, like other tin‐based anodes, SnSe2 suffers from poor cycle life and low rate capability due to large volume expansion during the repeated Li+ insertion/de‐insertion process. This work reports an effective and easy strategy to combine SnSe2 and carbon nanotubes (CNTs) to form a SnSe2/CNTs hybrid nanostructure. The synthesized SnSe2 has a regular hexagonal shape with a typical 2D nanostructure and the carbon nanotubes combine well with the SnSe2 nanosheets. The hybrid nanostructure can significantly reduce the serious damage to electrodes that occurs during electrochemical cycling processes. Remarkably, the SnSe2/CNTs electrode exhibits a high reversible specific capacity of 457.6 mA h g−1 at 0.1 C and 210.3 mA h g−1 after 100 cycles. At a cycling rate of 0.5 C, the SnSe2/CNTs electrode can still achieve a high value of 176.5 mA h g−1, whereas a value of 45.8 mA h g−1 is achieved for the pure SnSe2 electrode. The enhanced electrochemical performance of the SnSe2/CNTs electrode demonstrates its great potential for use in lithium‐ion batteries. Thus, this work reports a facile approach to the synthesis of SnSe2/CNTs as a promising anode material for lithium‐ion batteries.
Dual II Heterojunctions Metallic Phase MoS2/ZnS/ZnO Ternary Composite with Superior Photocatalytic Performance for Removing Contaminants
Authors: Zhao Dawei , Wu Tengteng , Zhou Yi 
Published: May 2019

AbstractFabricating a high‐performance photocatalyst to efficiently solve serious environmental problems is an urgent affair. Herein, a series of MoS2/ZnO composites were successfully fabricated through a facile hydrothermal route using Na2MoO4, (NH2)2CS and urchin‐like ZnO as precursors. According to the results of XRD and XPS, it was found that ZnS appeared in MoS2/ZnO composite; meanwhile, the content was positively correlated with the weight of the precursor (NH2)2CS. It should be noted that the morphology and the metallic phase content of MoS2 grown in situ on the surface of ZnO were affected by the molar ratio of Na2MoO4 and ZnO. Benefiting from the special dual II heterojunctions of MoS2/ZnS/ZnO ternary composite, the material exhibited excellent charge separation and transfer performances. In the photocatalytic measurements, the MoS2/ZnS/ZnO (Na2MoO4:ZnO 1:2 MZ2) composite not only exhibits excellent photocatalytic CrVI reduction activity of 42.3×10−3 min−1, but also displays remarkable adsorption performance (nearly 32.1 %) for Cr2
. In addition, the ternary composite shows dominant photocatalytic CrVI reduction activities compared to other photocatalysts. This work provides a high‐efficient MoS2/ZnS/ZnO ternary photocatalyst for environmental treatment.
Dead forests burning: the influence of beetle outbreaks on fire severity and legacy structure in sub‐boreal forests
Authors: Talucci Anna C. , Krawchuk Meg A. 
Published: May 2019

AbstractRecent regional mountain pine beetle (MPB) outbreaks have generated unprecedented tree mortality across the fire‐prone landscapes of western North American forests and could potentially modify fire severity and postfire ecological effects. In 2012, 2013, and 2014, three fires burned through high mortality, gray‐phase lodgepole pine‐dominated forests in the plateau regions of central interior British Columbia, Canada, providing an opportunity to test for interactions between MPB outbreaks and wildfires. We inventoried 63 plots that spanned gradients of outbreak severity, fire severity, and burning conditions in a wilderness setting. Our objective was to evaluate the influence of outbreak severity on fire severity by assessing typical first‐order fire effects as well as legacy structure related to the consumption of woody biomass on snags/trees. We found no evidence of a relationship between outbreak severity and fire severity for six of seven first‐order fire effects, with the exception of deep charring. We found evidence that legacy structure in the form of consumed branch structure and deep char development had greater odds of occurrence onMPB‐killed snags compared to trees killed during wildfire. Our results indicate two key findings. First, fire severity as it relates to most first‐order fire effects measures is not influenced by outbreak severity, instead it is more strongly influenced by the interaction of fuels, weather, and topography during fire events. Second, our results highlight how the interaction between outbreak severity and fire severity alters postfire structural legacies and their functional attributes, which could have important ecosystem implications.
Hg2NF, Analogue of HgO
Authors: Manjunath Krishnappa , Prasad Suchitra , Servottam Swaraj , Waghmare Umesh V. , Rao C. N. R. 
Published: May 2019

AbstractInvited for the cover of this issue is the group of Prof. C.àN.àR. Rao from Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India. The cover image shows the aliovalent substitution of N3– and F– in place of O2– in HgO to obtain Hg2NF.
Formation of Cholesterol Oxidation Products, Cholesterol Dimers and Cholestadienes After Thermal Processing of Cholesterol Standards and Butter
Authors: Derewiaka Dorota 
Published: May 2019

The aim of the study is to compare the transformation cholesterol standard and cholesterol present in a food matrix (butter) during thermal treatment at 150 and 180 °C for 1 h, which results in the formation of cholesterol oxidation products (0.5–189.3 mg g−1 of unheated standard and 0.044–0.063 mg g−1 of unheated butter) and cholesterol dimers (72.3–120.3 mg g−1 of unheated standard and 0.208 mg g−1 of unheated butter). The presence of cholesta‐3,5‐diene is investigated, especially in free cholesterol and cholesteryl palmitate unheated samples (105.3–116.4 mg g−1), as well as in thermally processed butter (0.009 mg g−1). Moreover, the processes of the extensive degradation of cholesterol are observed in standards samples (34.7–98.8% losses) compared to butter samples (25.5–73.5% losses). The qualitative and quantitative analyses of the above mentioned compounds are performed with the use of solid‐phase extraction, gas chromatography coupled with mass spectrometry and gel permeation chromatography. In conclusion, the thermal processing of butter and products containing cholesterol should be performed at mild temperatures, for example, 150 °C, because fewer negative components (e.g., oxysterols, cholesterol dimers) are formed in those conditions compared to heat processing at higher temperatures.Practical Application: The methods described in this study may be useful for the determination of sterols, oxysterols, cholesterol dimers, and cholesta‐3,5‐diene in standard cholesterol samples and cholesterol present in food products. The presented results data are crucial for the assessment of cholesterol changes during processing, especially the observation that some of the components have adverse effects on the human metabolism of oxysterols or cholesterol dimers. The investigations show that the thermal processing of products containing cholesterol should be performed at the lowest possible temperatures, for example, 150 °C, because this protects cholesterol from dimerization, oxidation, and degradation.Thermal processing of cholesterol can lead to the formation of cholesterol dimers, cholesterol oxidation products or cholestadienes, which can have adverse effect of the human health.
Oxidized Lipids Decrease Phagocytic Activity of ARPE‐19 Cells In Vitro
Authors: Pawlak Anna M. , Olchawa Magdalena , Koscielniak Anna , Zadlo Andrzej , Broniec Agnieszka , Oles Tomasz , Sarna Tadeusz J. 
Published: May 2019

Phospholipids, representing 80% of retinal lipids, contain a high level of polyunsaturated fatty acids, which are susceptible to oxidation. It has recently been shown that Folch’ extract of bovine neural retinas reveals moderate photoreactivity by generating reactive oxygen species upon irradiation with blue light. Importantly, the photoreactivity markedly increases upon oxidation of the exctracted lipids. In this work, the phototoxic potential of the Folch’ extract of bovine neural retinas (BRex), subjected to controlled oxidation, is studied in vitro employing a retinal pigment epithelium cell line (ARPE‐19). Multilamellar liposomes prepared from BRex, equilibrated with air, are oxidized in the dark at 37 °C for up to 400 h. The liposomes are then introduced into ARPE‐19 cells by phagocytosis. The impact of BRex at different stages of oxidation on viability and specific phagocytic activity of ARPE‐19 cells exposed to visible light is analyzed. While the oxidized BRex, at the light doses employed, does not induce any measurable killing of the cells, the treatment noticeably decreases their specific phagocytic activity.Practical Applications: Lipid oxidation products are commonly considered as an efficient protein modification factor occurring in the retina. Although possible consequences of oxidation of retinal lipids for the onset and development of age‐related macular degeneration are widely discussed, their potential photoreactivity and possible phototoxicity have not been considered. This is an important issue; taking into account that reactive products of lipid oxidation present in the outer retina, it may be exposed to short‐wavelength visible radiation. If photoreactive, peroxidized retinal lipids may act as acquired endogenous sensitizers increasing the risk of retina photodamage. In this work, the phototoxic potential of the Folch’ extract of bovine neural retinas (BRex), subjected to controlled oxidation, is studied in vitro employing a retinal pigment epithelium cell line (ARPE‐19).Lipids present in the retina are characterized by high level of unsaturation that makes them susceptible to oxidation. When oxidized, retinal lipids become photoreactive under visible light. Treatment of retinal pigment epithelium cells (ARPE‐19) with liposomes prepared from oxidized Folch’ extract of bovine neural retinas followed by irradiation with visible light, reduces phagocytic activity of ARPE‐19 cells.
Factors Affecting Antioxidant Activity of Amino Acids in Soybean Oil at Frying Temperatures
Authors: Hwang Hong‐Sik , Winkler‐Moser Jill K. , Doll Kenneth M. , Gadgil Mayuresh , Liu Sean X. 
Published: May 2019

Recently it is reported that some amino acids have strong antioxidant activity in frying oil showing potential as new natural antioxidants. This study attempts to examine some proposed mechanisms and to understand a few factors affecting antioxidant activities of amino acids. First, to understand the effect of the two major functional groups in an amino acid, carboxylic acid, and amino groups; β‐alanine and their derivatives are examined. Methyl 3‐aminopropanoate having an ester group (‐COOCH3) in place of the carboxylic acid group (‐COOH) of β‐alanine has stronger activity than β‐alanine, presumably, due to increased lipophilicity. 3‐(Dimethylamino)propionic acid containing a dimethylamino group (‐N(CH3)2) in place of the amino group (‐NH2) of β‐alanine also has slightly increased activity than β‐alanine. In general, antioxidant activity increases with increasing alkyl chain length of an amino acid. However, DL‐2‐aminobutyric acid (C4) and DL‐norleucine (C6) has higher activity than other analogs with a longer alkyl chain. Chelation of metals by an amino acid does not play an important role under the conditions used in this study. Dipeptides do not show stronger activity than the two constituent amino acids alone in soybean oil (SBO).Practical Application: Amino acids can practically be used as natural antioxidants for frying. Since this finding is very recent, very little is known about the antioxidant activity of amino acids, which must be investigated for the practical application. In this study, the understanding of several factors affecting their activity, which can be used in the practical application is attempted. It is found that, in general, antioxidant activity increases with increasing lipophilicity of an amino acid. Dipeptides do not show stronger activity than the two constituent amino acids alone. Therefore, a single effective amino acid instead of peptides or protein hydrolysates are recommended.Antioxidant activity of DL‐alanine derivatives with a longer alkyl chain. In general, higher lipophilicity provides higher antioxidant activity. However, DL‐2‐aminobutyric acid (C4) and DL‐norleucine (C6) has higher activity than other analogs with a longer alkyl chain, presumably, due to the combination of their lipophilicity and mobility.
Gas production from a silty hydrate reservoir in the South China Sea using hydraulic fracturing: A numerical simulation
Authors: Sun Jiaxin , Ning Fulong , Liu Tianle , Liu Changling , Chen Qiang , Li Yanlong , Cao Xinxin , Mao Peixiao , Zhang Ling , Jiang Guosheng 
Published: May 2019

AbstractThe low permeability of silty hydrate reservoirs in the South China Sea is a critical issue that threatens safe, efficient, and long‐term gas production from these reservoirs. Hydraulic fracturing is a potentially promising stimulation technology for such low‐permeability reservoirs. Here, we assess the gas production potential of a depressurization horizontal well that is assisted by the hydraulic fracturing using numerical simulation according to field data at site SH2 in this area. In addition, the number of horizontal wells drilled is discussed if commercial production is to be performed at this site. The results show that the production potential can be significantly stimulated at the early production stage by adopting hydraulic fracturing in this reservoir due to a better depressurization effect. However, the increase in gas recovery gradually decreases with the continuous dissociation of gas hydrates, and the evolution trend is similar to that in a reservoir without stimulation during later periods of gas production because the dissociation front gradually moves away from the fractures. From the perspective of production potential, using a horizontal well scheme assisted by the hydraulic fracturing technology for gas recovery from a hydrate deposit can sharply reduce the number of operation wells, shorten the drilling operation time, and boost the economic efficiency. The horizontal well scheme may be an effective way to increase the gas yield if the application of quickly deployed horizontal wells and hydraulic fracturing techniques in such hydrate reservoirs greatly increases in the near future.
The transmission characteristic for the improved wind turbine gearbox
Authors: Fan Zhixin , Zhu Caichao , Li Xiuhe , Liang Chengcheng 
Published: May 2019

AbstractThe structure of an improved wind turbine gearbox is presented for meeting the operation of the optimized wind turbine power‐wind speed curve (P‐v curve). When the wind speed is lower than the cut‐in wind speed, the operation mode of the wind turbine is changed by the extra power, which is supplied by the motor excited source to keep the wind turbine running. Moreover, the transmission principle of the improved wind turbine gearbox is discussed. Various motor power impacts on the transmission characteristic for the improved transmission structure are investigated and results are compared with the professional software. Results indicate that as the motor power increases, the transverse vibration of sun gears and meshing forces of the low‐speed and medium‐speed planetary stages decreases. The transverse vibration for the pinion gear of the high‐speed stage enhances with the increase of the motor power. Load‐sharing coefficients of the planetary gear stages are augmented with the enlargement of the motor power. It is found that meshing forces of the torque‐implement parallel stage are increased with augmentation of the motor power.
Late Quaternary biotic and abiotic controls on long‐term sediment flux in a northern Australian tropical river system
Authors: Larsen Annegret , May Jan‐Hendrik , Carah Xavier 
Published: May 2019

AbstractThe modern distribution of monsoonal rainforest in the Australian tropics is patchy and is mainly associated with river corridors and groundwater springs, which indicates a strong dependence on hydrologic and geomorphic conditions. While their present distribution is well known, very little data exists on past spatial and temporal dynamics of these ecosystems, or their medium‐ to longer‐term controls. Factors such as (i) fire frequency and type, and/or (ii) hydroclimatic conditions (e.g. droughts) have been proposed to control riverine corridor rainforest extent. Recent observations, however, also suggest an additional (iii) geomorphic control induced by alluvial knickpoint migration. Sediment sequences provide valuable archives for the reconstruction of longer‐term (a) floodplain sedimentary dynamics, (b) local vegetation history, and (c) catchment‐wide fire histories. This study investigates such a sediment sequence at Wangi Creek, and shows that a phase of aggradation, lasting ~4000 years, was recently disrupted by channel incision and floodplain erosion. The aggradational phase is characterized by sand deposition with average vertical floodplain accretion rates of 0.8 cm/yr and includes phases of soil development. The recent incisional phase has changed hydro‐geomorphic conditions and caused widespread degradation of vegetation, erosion and lowering of the macro‐channel surface. While there is no evidence in our data for an erosional event of similar magnitude since the onset of late Holocene floodplain aggradation, Wangi Creek experienced significant erosion and incision immediately before ~4000 years, providing the first evidence for a tropical cut‐and‐fill river system. We hence argue that phases of aggradation mainly controlled by biotic processes alternate and depend on feedbacks with incision phases controlled mainly by abiotic processes. The results show that eco‐hydro‐geomorphic feedbacks may play a crucial role in the medium‐ to longer‐term history of tropical fluvial systems and need to be considered when interpreting fluvial archives with regards to climate, fire or human induced change. © 2019 John Wiley & Sons, Ltd.
Analysis and design of an efficient handoff management strategy via velocity estimation in HetNets
Authors: Tiwari Ravi , Deshmukh Siddharth 
Published: May 2019

AbstractIn this paper, we present an efficient handoff decision strategy and a mobility state detection (MSD) scheme for heterogeneous networks (HetNets). Due to base station (BS) densification, HetNets occasionally face unnecessary handovers and service failures. Since velocity plays a crucial role in handover process, its knowledge is imperative for effective mobility management. Furthermore, due to limited power in mobile devices, emphasis is in investigation of velocity estimators that are at service provider end. Thus, we propose two maximum likelihood–based velocity estimators exploiting handover count and sojourn time measurements, respectively. Our analysis illustrates that both the estimators are asymptotically unbiased and efficient. In addition, we also notice that variance of sojourn time–based estimator is smaller than that of handover count–based estimator. Considering superiority of sojourn time–based estimator, we propose a handover decision strategy to minimize unnecessary handovers. Here, we first predict the sojourn time of upcoming BSs on the basis of velocity estimated via sojourn time samples. Next, BSs whose predicted sojourn time are greater than a prespecified threshold are then considered to identify the next serving BS. Finally, we select next serving BS on the basis of minimum cost for satisfying quality‐of‐service parameters such as bandwidth, security, monetary cost, and available power at user device. This work also exploits estimated velocity to investigate MSD specified in LTE standards. The numerical and simulation results validate our approach by illustrating accuracy in velocity estimation, reduction in frequent handovers and service failures, and improvement in MSD.
Adapting reinforcement learning for multimedia transmission on SDN
Authors: Rego Albert , Sendra Sandra , Garcia Laura , Lloret Jaime 
Published: May 2019

AbstractMultimedia transmissions require a high quantity of resources to ensure their quality. In the last years, some technologies that provide a better resource management have appeared. Software‐defined networks (SDNs) are presented as a solution to improve this management. Furthermore, by combining an SDN with artificial intelligence (AI) techniques, networks are able to provide a higher performance using the same resources. In this paper, a redefinition of reinforcement learning is proposed. This model is focused on multimedia transmission in an SDN environment. Moreover, the architecture needed and the algorithm of the reinforcement learning are described. Using the Openflow protocol, several sample actions are defined in the system. Results show that using the system users perceive an increase in the image quality three times better. Moreover, the loss rate is reduced more than half the value of losses recorded when the algorithm is not applied. Regarding bandwidth, the maximum throughput increases from 987.16 kbps to 24.73 Mbps while the average bandwidth improves from 412.42 kbps to 7.83 Mbps.