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A regression approach for seismic first-break picking

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Petroleum Science 2024年第3期21卷 1584-1596页

作者： Huan Yuan San-Yi Yuan Jie Wu Wen-Jing Sang Yu-He Zhao CNPC Key Laboratory of Geophysical Exploration China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration&Development—Northwest(NWGI) Key Laboratory of reservoir characterization of CNPCPetroChinaLanzhou 730020GansuChina

The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)***,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)*** address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target *** employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed *** from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and *** addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary *** picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large *** picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR *** subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed *** results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application.

关键词： First-break picking Low signal-to-noiseratio Regression BiLSTM Traveltime Geometry Noisy seismic data

Multi-scale habitat influences sprainting and group size of a freshwater-obligate smooth-coated otter(Lutrogale perspicillata) in Tungabhadra Otter Conservation Reserve, India

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Ecological Processes 2024年第1期13卷 159-175页

作者： Ankit Moun P.Ramesh Kumar M.Malathi Priya T.Ramesh Riddhika Kalle Sálim Ali Centre for Ornithology and Natural History Deputy Conservator of Forests Bellary Territorial Forest Division Deputy Conservator of Forests Working Plan and Survey and Research WingBellary Territorial Forest Division Centre for Functional Biodiversity University of Kwa Zulu-Natal

Background The impact of changing land-use patterns and associated anthropogenic threats on scale-dependent habitat use of semi-aquatic mustelids in scent-marking and social behaviour can provide important insights into the habitat ecology of smooth-coated otters(Lutrogale perspicillata).methods We sampled 180 stream segments(100–400 m) as spatial replicates of 60 1-km2 sites to record indirect evidence(i.e. spraints and mass latrine sites) and group sizes of smooth-coated otters along the Tungabhadra Otter Conservation Reserve(TOCR) during the dry season. To quantify habitat, we recorded stream characteristics, riparian vegetation, and anthropogenic disturbances at the local scale, and hydro-environmental characteristics and land uses at the landscape scale. Using Markovian-chain detection and occupancy models, we assessed the multi-scale habitat use of otters in their selection of suitable areas for scent-marking based on repeated presence-absence data on spraint/latrine locations along the TOCR. We further used linear regression techniques to explore relationships between the number of individuals in smooth-coated otter group and hydro-environmental characteristics, spraint/latrine encounter rate, anthropogenic pressure, land cover, topography, and *** At the local scale, the probability of spraint deposition and group size decreased with anthropogenic disturbance while the probability of spraint detections decreased with grass cover. At the landscape scale, the probability of otter site use for spraint deposition and group sizes increased in southeast flowing streams. Spraint deposition increased with the proportion of sugarcane fields, whereas in contrast, group size decreased with proportion of sugarcane *** Our findings highlight the first empirical evidence on multi-scale habitat use of a southern Indian population of smooth-coated otters in an inland freshwater ecosystem surrounded by the scrub jungle–agriculture matrix. We sug

关键词： Presence-absence modelling Inland river Freshwater ecosystem Semi-aquatic mammal Smooth-coated otter

Strategy and technique for surgical treatment of Ebstein’s anomaly

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Chinese Medical Journal 2024年第10期137卷 1218-1224页

作者： Qingyu Wu Xiaoya Zhang Mingkui Zhang Hongyin Li Dongya Zhang Lianyi Wang Qingfeng Wu Cardiac Center Division of Cardiac SurgeryThe First Hospital of Tsinghua UniversityBeijing 100016China

Background:Ebstein’s anomaly(EA)is a rare and complex congenital heart anomaly,and the effect of surgical treatment is not *** study aims to introduce our experience in management strategies,surgical techniques,and operative indications for patients with Ebstein’s ***:A retrospective study of 258 operations was performed in 253 patients by the same cardiac surgeon in The First Hospital of Tsinghua University between March 2004 and January 2020.32 patients had previously received cardiac surgery in other *** clinical data including diagnosis,operative indications,techniques,pathological changes,and survival rates were collected and ***:Anatomical correction was performed in 203(78.7%)operations,1½ventricle repair in 38(14.7%)operations,tricuspid valve repair only in four operations(1.6%),tricuspid valve replacement in ten(3.9%),total cavopulmonary connection(TCPC)in two(0.8%),and Glenn operation in one operation(0.4%).Reoperation was performed in five patients(2.0%)during *** them,tricuspid valve replacement was performed in one patient,1½ventricle repair in two patients,and tricuspid valve annulus reinforcement in two *** patients died with an early mortality rate of 2.0%.Complete atrioventricular conduction block was complicated in one patient(0.4%).A total of 244 patients was followed up(four in the 253 patients lost)with a duration of 3.0-168.0(87.6±38.4)*** function of 244 patients improved significantly with mean New York Heart Association(NYHA)functional class recovery from 3.5 to *** mean grade of tricuspid valve regurgitation improved from 3.6 to *** late deaths(1.2%)*** survival rates at five and ten years after surgery were 98.6%and 98.2%,*** was performed in five patients(2.0%)during the follow-up ***:Based on our management strategies and operative principles and techniques,anatomical correction of EA is capable of achiev

关键词： Ebstein’s anomaly Anatomical repair Surgical treatment Long-term result

Thermal stability improvement and microstructure optimization of high cobalt content Nd-Fe-B magnets via terbium grain boundary diffusion

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Journal of Rare Earths 2024年第8期42卷 1531-1538,I0004页

作者： Jiyuan Xu Ruiyang Meng Jing Liu Jiateng Zhang Rui Han Yikun Fang Shengzhi Dong Wei Li division of Functional Materials Research Central Iron and Steel Research InstituteBeijing100081China

The substitution of Fe by Co in the 2:14:1 phase is an effective method to increase the Curie temperature and enhance the thermal stability of the Nd-Fe-B ***,the accumulation of Co ele ment at the grain boundaries(GBs) changes the GBs from nonmagnetic to ferromagnetic and causes the thinlayer GBs to become rare,In this paper,the method of diffusing Tb element was chosen to improve the microstructure and temperature stability of high-Co *** original sintered Nd_(28.5)Dy_(3)-CO_(x)e_(bal)M_(0.6)B_(i)(x=0,6 wt%,12 wt%;M = Cu,Al,Zr) magnets with different Co contents were diffused with Tb by grain boundary diffusion(GBD).After GBD,high-Co magnets exhibit more continuously distributed thin-layer GBs,and their thermal stability is significantly *** high-Co magnets(x=6 wt%),the absolute value of the temperature coefficient of coercivity decreases from 0.603%/K to0.508%/K in the temperature range of 293-413 K,that of remanence decreases from 0.099%/K to 0.091%/K,and the coercivity increases from 18.44 to 25.04 *** electron microscopy(TEM)characterization reveals that there are both the 1:2 phase and the amorphous phase in the high-Co magnet before and after GBD,EDS elemental analysis shows that Tb element is more likely to preferentially replace the rare earth elements in the 2:14:1 main phase than in the 1:2 phase and the amorphous *** concentration of Tb at the edge of the main phase is much higher than that in the 1:2phase and amorphous phase,which is beneficial to the improvement of the *** preferential replacement of Tb elements at the edge of the 2:14:1 phase and thin-layer GBs with a more continuous distribution are synergistically responsible for improving the thermal stability of high-Co *** study indicates that GBD is an effective method to improve the microstructure and thermal stability of high-Co magnets.

关键词： Nd-Fe-B magnets Coercivity Grain boundary diffusion Thermal stability Micro structure Rare earths

Reflections on four decades of physical activity epidemiology

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Journal of Sport and Health Science 2024年第5期13卷 608-610页

作者： Barbara Sternfeld David R.Jacobs Jr. division of Research Kaiser Permanente Northern CaliforniaOaklandCA 94610USA division of Epidemiology and Community Health School of Public HealthUniversity of MinnesotaMinneapolisMN 55454USA

In 1985,Public Health Reports published a series of papers prepared for a workshop sponsored by the Centers for Disease Control and Prevention(CDC).1 Building on the seminal work of Jeremy Morris and Ralph Paffenbarger Jr.,who were among the first to use epidemiological methods to study physical activity(PA),2,3 the workshop itself was the result of a growing scientific understanding of the importance of“physical fitness and exercise for improving the health of the public”.

关键词： semi workshop Ralph

Mechanical and magneto-electronic properties of europium lanthanide-based cubic perovskites EuYO_(3)(Y=Cr, Mn, Fe): An ab initio study

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Journal of Rare Earths 2024年第3期42卷 562-569,I0005页

作者： Hayat Ullah Azra Sarwar Sajad Ali Rabah Khenata Abdelmadjid Bouhemadou Saad Bin-Omran Department of Physics Women University of Azad Jammu&Kashmir Bagh 10250Pakistan Department of Physics Abdul Wali Khan UniversityMardan23200KPPakistan LPQ3M Laboratory Institute of Science and TechnologyUniversity of Mascara29000MascaraAlgeria Laboratory for Developing New Materials and Their characterization Farhat Abbas University Setif l19000SetifAlgeria Department of Physics and Astronomy College of ScienceKing Saud UniversityP.O.Box 2455Riyadh11451Saudi Arabia

Computational calculations using density functional theory(DFT) were performed for the first time using the full potential linearized augmented plane wave plus local orbital method(FP-LAPW + LO) to determine the structural, elastic, electronic and magnetic properties of europium-based cubic perovskites EuYO_(3)(Y=Cr, Mn, Fe). The exchange correlation potentials of GGA along with some analytical methods were adopted for the computation of structural and elastic properties. Moreover, the GGA + U formalism was also added for obtaining more precise electronic and magnetic properties, particularly to address the Eu-4f and Y-3d orientations in the spin-polarized double cell symmetry. The observed lattice parameters of these compounds are consistent with experiment. The observed bulk moduli predict that EuCrO_(3) is harder and less compressible than EuMnO_(3) and EuFeO_(3). The calculated tolerance factors of these compounds are within the cubic symmetry range. Our computed critical radius of EuCrO_(3) shows that EuCrO_(3) has a larger migration energy. Based on their elastic properties, these compounds are ductile in nature. We also computed the thermal properties of these compounds. The band structures and density of states show that these compounds are metallic in character. The lowest ground state energy and magnetic moments of these compounds expose their ferromagnetic nature. The metallic nature and strong ferromagnetism of these compounds make them promising applicants for application in spintronic.

关键词： Perovskites GGA+U Elastic constants Band structure Magnetic moments Rare earths

Reconstitution of double-negative T cells after cord blood transplantation and its predictive value for acute graft-versus-host disease

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Chinese Medical Journal 2024年第10期137卷 1207-1217页

作者： Tianzhong Pan Peng Ding Aijie Huang Baolin Tang Kaidi Song Guangyu Sun Yue Wu Shiying Yang Xingchi Chen Dongyao Wang Xiaoyu Zhu Department of Hematology The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230001China Anhui Provincial Key Laboratory of Blood Research and Applications HefeiAnhui230001China Blood and Cell Therapy Institute Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230001China division of Life Sciences and Medicine University of Science and Technology of ChinaHefeiAnhui 230001China The First Affiliated Hospital of USTC Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230001China

Background:With an increasing number of patients with hematological malignancies being treated with umbilical cord blood transplantation(UCBT),the correlation between immune reconstitution(IR)after UCBT and graft-versus-host disease(GVHD)has been reported successively,but reports on double-negative T(DNT)cell reconstitution and its association with acute GVHD(aGVHD)after UCBT are ***:A population-based observational study was conducted among 131 patients with hematological malignancies who underwent single-unit UCBT as their first transplant at the Department of Hematology,the First Affiliated Hospital of USTC,between August 2018 and June *** differences were compared between the patients with and without ***:The absolute number of DNT cells in the healthy Chinese population was 109(70-157)/μL,accounting for 5.82(3.98-8.19)%of *** cells showed delayed recovery and could not reach their normal levels even one year after ***,the absolute number and percentage of DNT cells were significantly higher in UCBT patients without aGVHD than in those with aGVHD within one year(F=4.684,P=0.039 and F=5.583,P=0.026,respectively).In addition,the number of DNT cells in the first month after transplantation decreased significantly with the degree of aGVHD increased,and faster DNT cell reconstitution in the first month after UCBT was an independent protective factor for aGVHD(HR=0.46,95%confidence interval[CI]:0.23-0.93;P=0.031).Conclusions:Compared to the number of DNT cells in Chinese healthy people,the reconstitution of DNT cells in adults with hematological malignancies after UCBT was *** addition,the faster reconstitution of DNT cells in the early stage after transplantation was associated with a lower incidence of aGVHD.

关键词： Umbilical cord blood transplantation Graft-versus-host disease Immune reconstitution Double negative T Hematological Malignancies Treg cell Breg cell

Combined Insights from Leachate Structure and Microstructure Characteristics for Eating Quality of Convenience Rice Processed by Super-Heated and Pressurized Steam Technologies

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Rice science 2024年第4期31卷 475-488,I0035,I0036页

作者： Mingyo HA Hyo-Young JEONG Ju Hun LEE Hyun-Jung CHUNG division of Food and Nutrition Chonnam National UniversityGwangju 61186South Korea Department of Biotechnology College of Life Sciences and BiotechnologyKorea UniversitySeoul 02841South Korea division of Food Science&Culinary Arts Shinhan UniversityGyeonggi 11644South Korea

Convenience rice has become widely popular due to its easy availability for cooking. This study investigated the starch structure and composition of leachate and the microstructure of reheated convenience rice using novel processing technologies: super-heated steaming(SHS), auto-electric cooking(AEC), and pressurized-steam cooking(PSC). Additionally, the effect of two different target water contents(58% and 63%) was also evaluated. The PSC_63% sample had the highest total solids and amylopectin amount in the leachate. The amylopectin amount in the leachate differed significantly based on the targeted water content. Morphological characterization revealed that the swelling of starch and the coated layer on the surface of rice grains were most pronounced in the PSC_63% sample due to the pressure processing. The textural hardness of the AEC_58% sample was much higher than that of the other samples. The PSC_63% sample had the highest textural adhesiveness value, which can be attributed to the highest amylopectin amount in the leachate. Sensory characterization showed that the PSC_63% sample had the highest glossiness, whiteness, moistness, and overall acceptability. The principal component analysis score plots presented substantial differences in the leachate and textural and sensory characteristics of reheated convenience rice among the different processing technologies.

关键词： reheated convenience rice starch structure leachate multi-scale structure eating quality processing technology

Evaluation of excavation damaged zones(EDZs)in Horonobe Underground Research Laboratory(URL)

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 365-378页

作者： Koji Hata Sumio Niunoya Kazuhei Aoyagi Nobukatsu Miyara Obayashi Corporation Technology Research InstituteTechnology DivisionKiyoseTokyo204-8558Japan Obayashi Corporation Nuclear Facilities DivisionSinagawaTokyo108-8502Japan Japan Atomic Energy Agency Horonobe Underground Research CenterHoronobeHokkaido098-3224Japan

Excavation of underground caverns,such as mountain tunnels and energy-storage caverns,may cause the damages to the surrounding rock as a result of the stress *** this influenced zone,new cracks and discontinuities are created or propagate in the rock ***,it is effective to measure and evaluate the acoustic emission(AE)events generated by the rocks,which is a small elastic vibration,and permeability *** authors have developed a long-term measurement device that incorporates an optical AE(O-AE)sensor,an optical pore pressure sensor,and an optical temperature sensor in a single multi-optical measurement probe(MOP).Japan Atomic Energy Agency has been conducting R&D activities to enhance the reliability of high-level radioactive waste(HLW)deep geological disposal *** a high-level radioactive disposal project,one of the challenges is the development of methods for long-term monitoring of rock mass ***,in January 2014,the long-term measurements of the hydro-mechanical behavior of the rock mass were launched using the developed MOP in the vicinity of 350 m below the surface at the Horonobe Underground Research *** measurement results show that AEs occur frequently up to 1.5 m from the wall during *** addition,hydraulic conductivity increased by 2e4 orders of *** analysis revealed that the hydraulic behavior of the rock mass affected the pore pressure fluctuations and caused *** on this,a conceptual model is developed to represent the excavation damaged zone(EDZ),which contributes to the safe geological disposal of radioactive waste.

关键词： Excavation damaged zone(EDZ) Optical sensor Long-term monitoring Acoustic emission(AE) Shaft sinking