bluuebunny/crossref_metadata_2025_split huggingface dataset:
Type 2 diabetes albuminuric and non‐albuminuric phenotypes have different morphological and functional ultrasound features of diabetic kidney disease
Authors: Garofolo Monia , Napoli Vinicio , Lucchesi Daniela , Accogli Sandra , Mazzeo Maria Letizia , Rossi Piercarlo , Neri Emanuele , Del Prato Stefano , Penno Giuseppe 
Published: October 2022

AbstractAimsWhether different diabetic kidney disease (DKD) phenotypes recognise differences in morphological and vascular properties of the kidney is still unexplored. We evaluated the potential role of kidney ultrasonography in differentiating DKD phenotypes in subjects with type 2 diabetes.Materials and MethodsThis is a cross‐sectional, single‐centre study. Total (TRV) and parenchymal renal volumes (PRV) were calculated by applying the ellipsoid formula for conventional (2D) ultrasonography and with manual segmentation for 3D ultrasonography, and then adjusted for body surface area (aTRV, aPRV). Renal resistive index (RI) was contextually determined. DKD phenotypes have been defined based on increased urinary albumin‐to‐creatinine ratio (ACR >30 mg/g) and/or reduced eGFR (<60 ml/min/1.73 m2). Recruitment was planned to have groups of the same size.ResultsAmong 256 subjects, 26.2% had No‐DKD, 24.6% increased albuminuria only (Alb+), 24.2% non‐albuminuric DKD (Alb−DKD), and 25.0% albuminuric DKD (Alb+DKD). Compared to No‐DKD, RI was significantly higher in all DKD phenotypes, being the highest in Alb+DKD, and with a significant trend of RI > 0.70 to increase across phenotypes. In comparison with No‐DKD, both 2D and 3D volumes were increased in Alb+ and significantly reduced in Alb−DKD as well as in Alb+DKD, with significantly lower volumes in Alb−DKD as compared to Alb+DKD at the same reduced levels of eGFR. In adjusted regressions, compared to No‐DKD, RI was associated with Alb+; both RI and aPRV3D were associated with Alb+DKD; only aPRV3D with Alb‐DKD. Compared to No‐DKD, Receiver Operating Characteristic curve analyses, designed taking into account conventional risk factors, showed that US parameters did not ameliorate the characterisation of Alb+ and Alb+DKD, while aPRV3D significantly improved the phenotyping of Alb‐DKD.ConclusionsAs a novel information, we reported that, in type 2 diabetes, the emerging normoalbuminuric DKD phenotype showed reduced TRVs and PRVs even when compared, at similarly reduced eGFR levels, with Alb+DKD opening. In perspective, these findings suggest a possible role of imaging for better discrimination of DKD phenotypes in clinical practice.
Reactivity of Indolylmethylacetates with N, O, and S Soft Nucleophiles: Evidence of 2‐Alkylideneindolenines and 3‐Alkylideneindoleninium Generation by ESI‐MS and IRMPD Spectroscopy
Authors: Arcadi Antonio , Berden Giel , Ciogli Alessia , Corinti Davide , Crestoni Maria Elisa , De Angelis Martina , Fabrizi Giancarlo , Goggiamani Antonella , Iazzetti Antonia , Marrone Federico , Marsicano Vincenzo , Oomens Jos , Serraiocco Andrea 
Published: October 2022

AbstractThe synthesis of (aminomethyl), (tosylmethyl), and (aryloxymethyl) indoles starting from indolylmethylacetates and N, O, and S soft nucleophiles has been developed. ESI‐MS and IR multiple‐photon dissociation (IRMPD) spectroscopy analyses confirm the reaction proceeds through a conjugate addition of the nucleophile to 2‐alkylideneindolenines and 3‐alkylideneindoleninium.
Numerical analysis and optimization of the charging process on a shell‐and‐tube latent heat thermal energy storage unit for a solar power plant with direct steam generation
Authors: Deng Yajun , Zhu Zhengyue , Wang Wenzhao , Ye Qianhao , Yu Bo , Sun Dongliang 
Published: October 2022

AbstractA two‐dimensional model of the charging process on a heat storage unit in a shell‐and‐tube type latent heat subsystem of a solar power plant with direct steam generation was constructed in this study. The effects of the outer diameter to inner diameter ratio, aspect ratio, phase change material (PCM) thermal conductivity, and heat transfer fluid (HTF) mass flow rate were investigated. Results show that increasing the PCM thermal conductivity, HTF mass flow rate, and aspect ratio of the heat storage unit can shorten heat storage time, but the ratio of the outer diameter to the inner diameter of the heat storage unit has an optimal value of 6 in this problem. Using response surface methodology analysis, the influence of the aspect ratio, outer‐to‐inner‐diameter ratio, PCM thermal conductivity, and HTF mass flow rate on the storage time of the phase change heat storage unit is in descending order. After a genetic algorithm optimization, the storage rate of the heat storage unit increased by 35%. The results of this study can guide the heat storage unit to achieve a better practical application performance.
Flow field characteristic of water jet with air ring protective layer under submerged environment and the orthogonal optimization of nozzle structure
Authors: Zhang Liang , Qi Qingjie , Ma Tianfang , Sun Lifeng , Wang Yue , Chai Jiamei 
Published: October 2022

AbstractA water jet with an air ring protective layer is a promising rock‐breaking and cutting rate improvement method in submerged environment, such as oil–gas drilling. The jet flow field characteristic determines the jet impinge performance and is affected by nozzle structure parameters. In this study, the water jet flow with air ring under submerged environment was numerically simulated. The jet flow field structure with air ring was obtained by analyzing the distributions of jet velocity and air content at different cross sections. The effects of several critical nozzle structure parameters on jet isokinetic core length and axial velocity were investigated by adopting the orthogonal design method. The results show that the jet flow field structure with air ring in radial direction includes a high‐speed water jet zone, air ring protective layer, and air–water mixed zone, having the advantages of concentrated energy in axis region, long core section length, and low‐velocity attenuation. The influence degrees of nozzle structure parameters on jet core section length and axial velocity at X = 0.3 m are: length‐diameter ratio > outlet diameter > conic angle > air nozzle diameter > water‐air nozzle spacing and outlet diameter > length‐diameter ratio > conic angle > water‐air nozzle spacing > air nozzle diameter, respectively. The jet core section length and axial velocity both increase exponentially with the increasing outlet diameter, both first increase rapidly and then slowly decreases with the increase of conic angle and water–air nozzle spacing. There is the optimal conic angle of 15° and appropriate water–air nozzle spacing of 3–5 mm. With the increase of length–diameter ratio, they both first decrease rapidly and then slow down, indicating that conical nozzle is more suitable for water jet with air ring. And 0.9–1.2 mm is proper for the air nozzle diameter.
An advanced hydraulic fracturing technique: Pressure propagation and attenuation mechanism of step rectangular pulse hydraulic fracturing
Authors: He Pei , Lu Zhaohui , Deng Zhi , Huang Yongkui , Qin Dawei , Ouyang Liming , Li Menglai 
Published: October 2022

AbstractHydraulic fracturing technology has played a pivotal role as a key technology in shale gas development, but the geological environmental problems caused have been worrying the public. This paper proposes an advanced step rectangular pulse hydraulic fracturing technique, which can achieve higher pressure and more complex fractures by pumping lower energy fluid. The results indicate that the pressure propagation of step rectangular pulse hydraulic fracturing can be divided into stable and unstable propagation stages. Compared with conventional hydraulic fracturing, longer unsteady propagation time, higher pressure and more complex pressure distribution can be obtained. Step pulse parameters are discussed. We found that the pulse pressure increases linearly with the increase in pulse amplitude. There are optimal pulse frequencies and comprehensive damping coefficients to get optimal fluid pressure in different shale reservoirs. These research results will help reduce geological environmental hazards, and can also provide guidance for the optimization of step rectangular pulse hydraulic fracturing technology in shale reservoirs.
Study on the distribution and connectivity of organic matter pores in Longmaxi shale based on 2D and 3D FIB‐SEM
Authors: Hui Dong , Zhang Yan , Hu Yong , Peng Xian , Li Longxin , Zhao Zihan , Liu Xixiang , Li Tao , Pan Yi 
Published: October 2022

AbstractKnowledge of shale pore structure characteristics is crucial to understand gas storage and seepage mechanisms. Organic matter (OM) pores are considered the most important pore type in shale, and one of the currently significant research questions focuses on the spatial distribution and connectivity of OM pores. To answer this question, typical OM‐rich siliceous shale samples from the Lower Silurian Longmaxi Formation were comprehensively investigated using focused ion beam scanning electron microscopy. A three‐dimensional model of the OM‐rich region of interest was segmented and reconstructed based on numerous two‐dimensional slices. The types of OM were found to control the development of organic pores, and OM pores including honeycomb‐shaped pores, spongy‐shaped pores, and slit‐like irregular pores are mainly formed in the pyrobitumen. The pore structure parameters of the OM‐rich ROI revealed that the pore size distribution of honeycomb‐shaped OM pores formed in the pyrobitumen was mainly distributed in the range of 10–50 and 80–100 nm, while the throat equivalent diameter distribution demonstrated a unimodal curve with the main peak located at approximately 30 nm. Pore connectivity analysis further indicated that pyrobitumen also contained several isolated nano‐pores, and pores with diameters smaller than 40 nm were poorly connected. Furthermore, permeability simulation revealed clear discrepancies in different directions owing to the heterogeneity of the OM pores. These findings provide experimental evidence for the assessment of shale gas resources and their development potential.
Simulation of carbon emission for mining‐separating‐backfilling integrated coal mines based on system dynamics
Authors: Long Shuangshuang , Wang Xiangqian , Guo Puhao 
Published: October 2022

AbstractClarifying the influencing factors of energy consumption in underground production processes of coal mine is the premise and foundation for the coal mining industry to control the energy consumption and intensity to achieve the goal of carbon peak and carbon neutrality. This paper aims to investigate and compare the differences in energy consumption and carbon emissions between a mining‐separating‐backfilling integrated coal mine (MSBICM) and a traditional coal mine and explore the effects of the main production links underground on carbon emission intensity in coal mines. Hence, taking an MSBICM in Henan province as an example, this study constructed an energy consumption and carbon emission model of the mine using system dynamics (SD) method. Based on this model, the energy consumption of the main production logistics system and auxiliary production system in MSBICM was simulated and analyzed. In addition, this study made a comparative analysis of the energy consumption of the different production links in the two types of coal mines. The results showed that: (1) the comprehensive mechanized coal mining with solid filling system and ventilation system were the subsystems with the highest and lowest energy consumption in MSBICM respectively. (2) The influence rates of raw coal mining, gangue filling, coal‐gangue separating, and material transportation on carbon emission intensity in coal mine were 1.09%, 1.34%, 1.09%, and 5.13%, respectively. (3) Under the same production and filling targets, energy consumption of underground transportation systems in MSBICM was found to be 336.66 tons of standard coal less than that in traditional coal mine. This study has helped clarify the complex relationships among the factors that influence energy consumption in coal mines and provided a reference for implementing dual control of energy consumption to promote low‐carbon mining of coal resources.
Modeling the impacts of climate change on monthly commercial sector electricity consumption: A case of Suzhou, China
Authors: Su Zhenyu , Zhou Zhifan 
Published: October 2022

AbstractMultiple regression equations are the most common method for modeling the influences of climate variables on electricity demand. However, the multiple regression equations based on time series data often suffer from the problem of serial correlation or heteroskedasticity, resulting in biased estimation of the coefficients of parameters. Given that previous studies have paid less attention to such issues, in quantifying the effects of climate change on monthly commercial electricity consumption, in Suzhou, China, we paid more attention to the detection of the autocorrelation or heteroskedasticity that exists in a regression model. The results confirm that if a regression equation suffers from autocorrelation or heteroskedasticity, taking the necessary remedial measures can significantly improve the goodness of fit for the model. Again, it also found that if the temperature is less than the lower limit of the comfort zone, the relationship between climate change and electricity consumption is linear; if the temperature exceeds the upper limit of the comfort zone, this relationship is nonlinear, and a quadratic curve is more appropriate for modeling this relationship.
Optimal sizing of hybrid renewable energy systems for reliability enhancement and cost minimization using multiobjective technique in microgrids
Authors: Vaka Srinivas Sandeep Kumar Reddy , Matam Sailaja Kumari 
Published: October 2022

AbstractMicrogrids can meet their electrical energy needs through the use of renewable energy systems and energy storage. Combining hybrid renewable energy system (HRES) with a battery energy storage system (BESS) is the best way to increase the systems reliability while still satisfying load demand. Suitable sizing of microgrid with optimal power allocations of HRES and BESS in terms of capacity and discharge leads to improved reliability. Cost and reliability are two important aspects of microgrid system functioning. While designing the system with HRES and BESS, there must be an appropriate balance between cost and reliability. This paper presents an algorithm for optimal design of HRES with BESS for optimizing levelized cost of electricity (LCOE) and power supply reliability factor (PSRF) Particle swarm optimization and epsilon constraint based multi‐objective PSO algorithms are used to solve the objectives considering 24 hours time horizon. A hybrid Wind‐PV system with Diesel Generator and BESS is considered for the study. In this work, 12 trails of simulation runs are made to obtain accurate values of average levelized cost of electricity and power supply reliability factor along with the optimal power allocations of DGs and BESS. According to the findings, sizing of HRES with BESS optimally lowers the LCOE by reducing the quantity of power drawn from the grid and improves PSRF. ε‐MPSO provides the optimal results in minimizing the LCOE by obtaining proper energy management between HRES and BESS with improved reliability.
Performance investigation of electric vehicle battery thermal management system using nano fluids as coolants on ANSYS CFX software
Authors: Wankhede Sagar , Kamble Laxman 
Published: October 2022

AbstractBecause of their sophisticated cell chemistry when compared to other types of cell technology now in use, lithium‐ion batteries are commonly used in electric vehicles. These lithium‐ion cells must be operated within certain range of working temperatures but as the energy requirements increase the cells cross the operating bandwidth of temperature and thus cooling of lithium‐ion batteries becomes necessary for its optimal performance. Battery cooling has thus emerged as an important area of research as lithium‐ion batteries do not perform well on higher temperature ranges. Thus, cooling of the batteries using a cooling system is been focused upon and various battery cooling techniques are developed using various coolants such as air, liquid, phase change material and many more. The current study is focused on the use of liquid cooling method for cooling the lithium‐ion battery pack. This paper focuses on the use of nano fluids as coolants for cooling of the lithium‐ion battery pack due to its enhanced thermal conductivity and low viscosity at higher temperature which cools the battery pack. Nanoparticles such as aluminium oxide, titanium dioxide and copper oxide which when mixed with water (base fluid) form the nano fluid solution whose properties are simulated using governing equations. The paper also validates the cooling performance of nano fluids over currently used coolants using ANSYS CFX solver. The findings reveal that using nano fluids as coolants definitely aids in lowering battery pack (BP) temperatures, and nano fluids have a higher heat rejection rate than water. Comparing aluminium oxide, copper oxide, titanium di‐oxide as a coolant for battery thermal management system, Al2O3 nano fluids exhibit the greatest temperature reduction, followed by CuO and TiO2 nano fluids, respectively.
Hydrogen storage studies of Co, Fe, Fe3C nanoparticles encapsulated nitrogen doped carbon nanotubes
Authors: Dhanya A. R. , Ranjan Nisha , Ramaprabhu Sundara 
Published: October 2022

AbstractThe most crucial part of the hydrogen economy is the development of a hydrogen storage material which will be cost effective and its hydrogen storage capacity meets US DOE target. This study is an attempt to develop an efficient hydrogen storage material from a simple, one step synthesis technique. Herein, we synthesize metal nanoparticles encapsulated (M = Co, Fe, Fe3C) nitrogen doped carbon nanotubes (M/NCNT) for the efficient hydrogen adsorption within temperature range of 25°C to 100°C and at pressures 5 to 18 bar. The phase, morphology, surface area, and composition of the encapsulated metal nanoparticles NCNT were confirmed by different characterization techniques. Fe/NCNT is observed to have the highest hydrogen storage capacity of 3.3 wt% at room temperature, ~16 bar pressure, and the highest isosteric heat of adsorption (Qst) of 13 kJmol−1, among all. B,N‐CNTs reported 0.35 wt% hydrogen storage capacity at ~16 bar H2 equilibrium pressure and room temperature. The large surface area, defects produced on the CNT due to N doping as well as the presence of metal nanoparticles both inside, on the CNTs which results in the spillover mechanism for the dissociation of the hydrogen molecules into atoms and its diffusion through carbon layers within the CNT, are the factors that contribute to the enhancement of hydrogen storage capacity in M/NCNT.
Statistical methods for cis‐Mendelian randomization with two‐sample summary‐level data
Authors: Gkatzionis Apostolos , Burgess Stephen , Newcombe Paul J. 
Published: October 2022

AbstractMendelian randomization (MR) is the use of genetic variants to assess the existence of a causal relationship between a risk factor and an outcome of interest. Here, we focus on two‐sample summary‐data MR analyses with many correlated variants from a single gene region, particularly on cis‐MR studies which use protein expression as a risk factor. Such studies must rely on a small, curated set of variants from the studied region; using all variants in the region requires inverting an ill‐conditioned genetic correlation matrix and results in numerically unstable causal effect estimates. We review methods for variable selection and estimation in cis‐MR with summary‐level data, ranging from stepwise pruning and conditional analysis to principal components analysis, factor analysis, and Bayesian variable selection. In a simulation study, we show that the various methods have comparable performance in analyses with large sample sizes and strong genetic instruments. However, when weak instrument bias is suspected, factor analysis and Bayesian variable selection produce more reliable inferences than simple pruning approaches, which are often used in practice. We conclude by examining two case studies, assessing the effects of low‐density lipoprotein‐cholesterol and serum testosterone on coronary heart disease risk using variants in the HMGCR and SHBG gene regions, respectively.
The fluid definition of the ‘waters of the United States’: Non‐uniform effects of regulation on US wetland protections
Authors: Wade Jeffrey , Kelleher Christa , Ward Adam S. , Schewe Rebecca L. 
Published: October 2022

AbstractRecent revisions to the definition of the ‘waters of the United States’ (WOTUS) have considerably altered how wetlands are federally regulated under the Clean Water Act. The two most recent modifications to WOTUS, the Clean Water Rule (CWR) and the Navigable Waters Protection Rule (NWPR), represent two opposing approaches to the federal wetland policy. The impacts of these two rules on the regulation of wetlands have as of yet been poorly characterized at broad spatial scales. Using New York State (NYS) as a case study, we evaluated the jurisdictional statuses of more than 253 000 wetlands under the CWR and the NWPR to assess the landscape‐scale effects of WOTUS re‐definitions. We found that statewide and within each of NYS's hydrologic regions, the NWPR protects fewer wetlands and less total wetland area than the CWR. The efficacy of the two regulations varied considerably in space across NYS, highlighting the need for comprehensive, nationwide assessments of wetland policy outcomes. We also observed that both rules produced non‐uniform patterns in jurisdiction across a range of landscape positions and wetland sizes, preferentially protecting large wetlands close to the stream network. This effect was particularly pronounced under the NWPR, which excludes all geographically isolated wetlands from protection. Our findings in NYS emphasize the existence of unique patterns in protected wetlands across spatial scales, highlighting the value in applying geospatial analyses to evaluate environmental policy.