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Results of endoscopic retrograde cholangiopancreatography procedures at surgical clinics:A multicenter observational study in Türkiye 被引量:1
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作者 Sezgin Yilmaz Esat Taylan Ugurlu +26 位作者 Alpen Yahya Gumusoglu Mahmut Said Degerli Kemal Dolay Emre Balli Yasin Kara Ali Kocataş EkremÇakar Bünyamin Gürbulak Sercan Yüksel Soykan Arikan Hasan Bektaş Yusuf Emre Aytin Doğan Albayrak Ali Fuat Kaan Gok Cemalettin Ertekin Alpaslan FedayiÇalta Serhat Oğuz MustafaÖrmeci Ali HaldunÖzcan BarışSevinç Ömer Karahan İhsan Tümkaya Osman Kones Mehlika Bilgi Kirmaci Mustafa Yavuz Emrah Akın Merve Yeşilsancak 《World Journal of Gastrointestinal Surgery》 2025年第5期249-256,共8页
BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP)is an invasive endoscopic procedure used mainly to treat hepato-pancreato-biliary(HPB)diseases.The need for ERCP has increased with the rising number of H... BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP)is an invasive endoscopic procedure used mainly to treat hepato-pancreato-biliary(HPB)diseases.The need for ERCP has increased with the rising number of HPB diseases over the past decade.Thus,due to increased demand,ERCP is performed at more centers.Currently,it is performed by general surgeons,gastroenterology and invasive radiology specialists in the United States and Europe as recommended by the British Society of Gastroenterology(BSG).AIM To present the results of ERCP procedures from fourteen surgical centers in Türkiye.METHODS Fourteen surgical centers performing ERCP were included in the present study.The age,gender,ERCP indication,success status,post-ERCP complications,ERCP reports and the files of 66993 patients who underwent ERCP were collected from the participating centers.The results are discussed according to the targets declared by the BSG,which are volume load per annum,proportion of successful cannulation(>85%),bile duct clearance rate(>75%),stenting rate for strictures(>80%)and complications(<6%).RESULTS A total of 66993 ERCP procedures were performed in the centers included in the study up to August 2024.29250(43.6%)of the procedures were performed urgently,especially for suppurative cholangitis,biliary tract injuries,etc.The remaining 37743(56.4%)cases were performed electively.50.2%of the patients were female and 49.8%were male.The average ages were 56.5 years for women and 55.9 years for men.General anesthesia was used in 84.1%of the patients while sedation was used in 15.9%.The indications were bile duct stone(78.7%),pancreatic tumor(3.9%),papillary tumor(3.3%),cholangiocarcinoma(2.6%),Oddi sphincter dysfunction(2.4%),bile leakage after cholecystectomy(2%),bile leakage after hydatid cyst surgery(1.9%),biliary stricture(1.7%),and other diseases(3.1%).Hyperamylasemia and post-ERCP pancreatitis were the most common complications as observed in 8.1%of the patients.They were usually self-limited and responded to supportive measures.The frequency of the other complications was also consistent with the literature.CONCLUSION There is a huge shortage of ERCP endoscopists worldwide due to insufficient ERCP training and centers especially in developing and underdeveloped countries.As patients requiring ERCP usually present to surgical practitioners,the incorporation of surgeons into this training program is an effective and reliable solution.The BSG recommends the incorporation of surgeons and radiologists in addition to gastroenterology specialists.This study is the first to present the results of ERCP procedures from fourteen surgical centers throughout Türkiye.The results suggest that the surgical centers included were able to achieve the targets set by the BSG.This study demonstrated that the surgical ERCP units in the present work have reached satisfactory results and provided a reliable and successful ERCP service.There are currently no issues regarding the validity and appropriateness of the surgeons performing ERCP.Therefore,ERCP training should be encouraged in surgeons and more surgical ERCP centers should be provided. 展开更多
关键词 Endoscopic retrograde cholangiopancreatography General surgeon Education Endoscopic retrograde cho-langiopancreatography training Surgical centers Endoscopic retrograde cholangiopancreatography endoscopist
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Impact of adhesive layer properties on ceramic multi-layered ballistic armour systems: A review
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作者 Ethan I.L.Jull Richard Dekker Lucas Amaral 《Defence Technology(防务技术)》 2025年第5期292-303,共12页
The role of the adhesive layer in the ballistic performance of ceramic multi-layer armour system is complex and multi-faceted,often with trade-offs between single-and multi-hit performance.However,research focused on ... The role of the adhesive layer in the ballistic performance of ceramic multi-layer armour system is complex and multi-faceted,often with trade-offs between single-and multi-hit performance.However,research focused on untangling the underlying impact of varying adhesive cohesive or adhesion properties is limited and sometimes appears to provide conflicting conclusions.Comparison between the available studies is also often difficult due to variations in armour systems or ballistic testing being conducted.This review scrutinises the available research,identifying six critical properties of an adhesive layer in determining ballistic performance:elastic modulus,fracture strain,acoustic impedance,tensile bond strength,shear bond strength,and thickness.The impact of each of these properties on ballistic performance is discussed in detail,with clear description of the underlying processes involved,allowing clear optimisation goals to be established depending on the ceramic armour specification. 展开更多
关键词 CERAMIC BALLISTIC Armour ADHESIVE EPOXY POLYURETHANE
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Analysis of recurrence after stapled hemorrhoidopexy in grade IV hemorrhoid disease
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作者 Ahmet Erkek Muhammed K Yıldırak +1 位作者 Abdullah Yıldız BarışSevinç 《World Journal of Gastrointestinal Surgery》 2025年第8期230-235,共6页
BACKGROUND Stapled hemorrhoidopexy(SH)is one of the most commonly used surgical techniques for hemorrhoidal disease,being particularly effective for grade III and IV hemorrhoids.The procedure is associated with better... BACKGROUND Stapled hemorrhoidopexy(SH)is one of the most commonly used surgical techniques for hemorrhoidal disease,being particularly effective for grade III and IV hemorrhoids.The procedure is associated with better short-term outcomes,including less postoperative pain,shorter operative time,faster return to work,and higher patient satisfaction.However,there is a risk-benefit debate surrounding SH due to significant complications from the procedure,such as anal stenosis,rectovaginal fistula,fecal incontinence,and recurrence.AIM To evaluate recurrence rates and factors influencing surgical outcomes following SH in patients with grade III and IV hemorrhoids.METHODS This retrospective,single-center study enrolled a total of 77 patients with grade III/IV hemorrhoids for analysis.Early(less than 7 days after SH)and late(7 or more days after SH)complications were analyzed.Recurrence rates were calculated as well.RESULTS Patients were categorized by hemorrhoid grade and showed no differences in demographic data between the two groups.Recurrence was observed in 4 patients(23.6%)with grade IV hemorrhoids,and no recurrence was noted in patients with grade III hemorrhoids.Postoperative bleeding,incomplete defecation,urgent defecation,incontinence,skin tags,and anal fissure were complications reported by both groups.CONCLUSION Due to the high recurrence rate,SH is not an appropriate treatment option for patients with grade IV hemorrhoids.Open surgery may be a more suitable option for these patients. 展开更多
关键词 HEMORRHOIDS Stapled hemorrhoidopexy Procedure for prolapsed hemorrhoids Surgery RECURRENCE
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Practical and Risk-Based Management of Potential PFAS Contamination for Your Project
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作者 Wendy A.Presler Kristen Freiburger Stephen B.Ellingson 《Journal of Civil Engineering and Architecture》 2025年第6期279-287,共9页
PFASs(per-and polyfluoroalkyl substances)are a group of more than 12,000 man-made chemicals used in industrial,commercial,and consumer products since the 1940s.Their unique chemical structure resists degradation and t... PFASs(per-and polyfluoroalkyl substances)are a group of more than 12,000 man-made chemicals used in industrial,commercial,and consumer products since the 1940s.Their unique chemical structure resists degradation and they are often referred to as“forever chemicals”because of how long they persist in the environment.PFASs are also known to accumulate in human tissue.Exposure to certain PFAS at very low concentrations can cause kidney and testicular cancer,hormone disruption,and liver and thyroid diseases.Based on our experience managing PFAS impacted soil and groundwater at geotechnical construction vertical(structures)and horizontal(infrastructure and roads)projects,we present case studies to describe the current federal and state regulatory landscape for this group of emerging contaminants.This paper will provide a summary of basic sampling,testing,and risk-assessment approaches as well as solutions for cost effective treatment and acceptable disposal options. 展开更多
关键词 PFAS AFFF(aqueous fire-fighting foam) groundwater contamination soil contamination
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Experimental investigation of hybrid enhanced oil recovery techniques for Ugnu Heavy Oil on Alaska North Slope
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作者 Temitope Fred Ogunkunle Hyun Woong Jang +4 位作者 Asad Hassan Syed Rian Billings Lixing Lin Yin Zhang Abhijit Dandekar 《Petroleum Science》 2025年第2期710-723,共14页
The Alaska North Slope(ANS)is endowed with a substantial reservoir of heavy oil,estimated at 12-18billion barrels,primarily concentrated within the Ugnu reservoirs.These deposits,situated at depths ranging from 2000 t... The Alaska North Slope(ANS)is endowed with a substantial reservoir of heavy oil,estimated at 12-18billion barrels,primarily concentrated within the Ugnu reservoirs.These deposits,situated at depths ranging from 2000 to 4000 feet,lie in close proximity to the permafrost and have undergone biodegradation,resulting in in-situ viscosities reaching thousands of centipoise.Following the success in recovering the somewhat less heavy,viscous oils through polymer injection,the deposits in Ugnu Formation are garnering significant interest.Although thermal recovery methods are commonplace for heavy oils,applying these methods on ANS is impractical,given the adjacency to continuous permafrost.Therefore,non-thermal hybrid enhanced oil recovery(cEOR)methods,such as solvent(e.g.,CO_(2))and low salinity water(LSW),or LSW and polymer-based techniques,emerge as the primarily feasible options for recovering these vast heavy oil resources.This study experimentally investigates,via systematically carried out fluid property and phase behavior tests and a series of sand-pack coreflood experiments,the potential to enhance the recovery of Ugnu heavy oils.The coreflood experiments reveal the synergistic effect of combining liquid-CO_(2)with LSW to be the most promising approach in this study as a water alternating gas(WAG)process results in the cumulative recovery factor of 83.5%,doubling the recovery obtained by continuous low salinity waterflood.Additionally,the liquid-CO_(2)-LSW WAG process demonstrated an additional benefit for CO_(2)storage,with about 25%of the pore volume of the liquid-CO_(2)injected being sequestered at the end of the injection process.This significant recovery improvement is attributed to a substantial reduction of oil viscosity upon contact with the liquid CO_(2)during the soaking period,with a reduction of up to 95%of the original oil viscosity.Meanwhile,in-situ emulsion generation was observed in the oil produced from the continuous LSW flooding.This was also evident by the increased differential pressure across the sand-pack compared to that of the liquid-CO_(2)alternating LSW process.The promising results of this study indicate significant potential for liquid-CO_(2)alternating LSW injection as an effective cEOR technique for Ugnu heavy oils. 展开更多
关键词 Ugnu Heavy oilCO_(2) PolymerLow-salinity water Waterflood
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Methods for separating the noise produced by the wheels and track during a train pass‑by
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作者 David Thompson Dong Zhao +4 位作者 Giacomo Squicciarini Martin Toward Ester Cierco Erwin Jansen Michael Dittrich 《Railway Engineering Science》 2025年第3期342-358,共17页
Rolling noise is produced by vibration of the wheels and track,induced by their combined surface roughness.It is important to know the relative contributions of the different sources,as this affects noise control stra... Rolling noise is produced by vibration of the wheels and track,induced by their combined surface roughness.It is important to know the relative contributions of the different sources,as this affects noise control strategies as well as acceptance testing of new rolling stock.Three different techniques are described that aim to use pass-by measurements to separate the wheel and track components of rolling noise.One is based on the TWINS model,which is tuned to measured track vibration.The second is based on the advanced transfer path analysis method,which provides an entirely experimental assessment.The third is based on the pass-by analysis method in combination with static vibroacoustic transfer functions which are obtained using a reciprocity method.The development of these methods is described and comparisons between them are presented using the results from three experimental measurement campaigns.These covered a metro train,a regional train and a high-speed train at a range of speeds.The various methods agree reasonably well in terms of overall trends,with moderate agreement in the mid-frequency region,and less consistent results at low and high frequency. 展开更多
关键词 Railway noise Rolling noise Source separation Pass-by tests
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Imaging evaluation of periprosthetic loosening:A primer for the general radiologist
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作者 Sahil S Shet Eid Kakish +4 位作者 Stephen Christopher Murphy Ryan Roopnarinesingh Stephen P Power Michael M Maher David J Ryan 《World Journal of Radiology》 2025年第2期1-10,共10页
In response to an ageing global population,the primary hip and knee arthroplasty rate continues to increase.Although an effective treatment,up to 25%patients may require revision arthroplasty during their lifetime,com... In response to an ageing global population,the primary hip and knee arthroplasty rate continues to increase.Although an effective treatment,up to 25%patients may require revision arthroplasty during their lifetime,commonly due to periprosthetic loosening.Revision procedures are associated with significantly increased healthcare costs;therefore,timely and accurate diagnostics are critical for clinicians and patients.Loosening,which may be septic or aseptic,remains a challenge and requires thorough clinical examination and multimodal imaging evaluation.Plain radiographs remain an essential diagnostic tool but advanced imaging modalities such as computed tomography,magnetic resonance imaging and nuclear medicine are playing an increasingly important role.This comprehensive review,through outlining the available radiological modalities,their respective strengths and weaknesses and the pertinent imaging findings,may help radiologists and orthopaedic surgeons make more informed decisions in the management of periprosthetic loosening. 展开更多
关键词 Periprosthetic loosening Total hip replacement Total knee replacement Diagnostic radiology Aseptic loosening
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Antioxidant Potential of Different Plant Part of Allium roseum L.from Montenegro
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作者 Zoran S.Ilic Ljiljana Stanojevic +4 位作者 Lidija Milenkovic Ljubomir Sunic Dragana Lalevic Aleksandra Milenkovic Zarko Kevresan 《Phyton-International Journal of Experimental Botany》 2025年第8期2515-2527,共13页
This study aims to determine the phytochemical composition and antioxidant activity(AA)of different plant parts(bulbs,stalk,leaves and flowers)of wild rosy garlic(Allium roseum)from Montenegro.The flower exhibited the... This study aims to determine the phytochemical composition and antioxidant activity(AA)of different plant parts(bulbs,stalk,leaves and flowers)of wild rosy garlic(Allium roseum)from Montenegro.The flower exhibited the highest concentration of total phenols(55.7 GAE/g d.e.),followed by the leaf(25.6mg GAE/g d.e.).The leaf displayed the highest concentration of total flavonoids(41.48 mg RE/g d.e.),followed by the flower(36.26 mg RE/g d.e.)and top part of the stalk(26.80 mg RE/g d.e.).The AA of different parts of A.roseum after 60 min of incubation decreased in the following order:flower(0.15mg/cm^(3))>upper stalk(0.32mg/cm^(3))>leaf(0.36mg/cm^(3))>basal stalk(0.80mg/cm^(3))>bulb(1.53 mg/cm^(3)).The flowers exhibited the lowest EC_(50) values,indicating the highest antioxidant potential throughout the entire incubation period.Among all plant parts analyzed,the flowers demonstrated the highest ferric reducing antioxidant power(FRAP),reaching 24.99 mg Fe^(2+)/g,thereby indicating their superior antioxidant potential.Given their edibility,pleasant flavor,and high nutritional value,A.roseum flowers may be considered a promising natural additive for functional food products or culinary applications,including dish enhancement and decoration. 展开更多
关键词 Rosy garlic plant part PHENOLS flavonoids antioxidants
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The lifespan mechanism of dipole eddies to the east of Vietnam and their intrinsic connections
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作者 Yang JIN Meibing JIN +1 位作者 Changming DONG Dongxiao WANG 《Journal of Oceanology and Limnology》 2025年第5期1375-1388,共14页
A cyclonic eddy(CE)is often accompanied by an anticyclonic eddy(AE)to the east of Vietnam in the South China Sea(SCS)in summer,but the dipole lifetime and the intrinsic connection between CE and AE are still understud... A cyclonic eddy(CE)is often accompanied by an anticyclonic eddy(AE)to the east of Vietnam in the South China Sea(SCS)in summer,but the dipole lifetime and the intrinsic connection between CE and AE are still understudied.Data from 1993-2021 reveal that the dipole lifetime are significantly correlated with the wind direction and speed in the dipole region.Higher wind speed was found to be associated with more eastward wind direction and tends to longer dipole lifetime.The wind stress work(WW)on the eddy is much stronger in the eastward jet region than in the CE and AE regions.Comparing of results of 12 higher and lower wind speed years reveal that higher wind can produce stronger mean current,WW and barotropic instability(T4)that further enhances eddy kinetic energy(EKE)and dipole lifetime.The correlations between the dipole CE and AE characteristics are insignificant on interannual scales and mostly insignificant on seasonal scales in the surface layer but significant on seasonal scales in the subsurface layers.In addition,the daily mean vertical profiles(0-500 m)of EKE,vorticity and total deformation rate(TD)between CE and AE remain significantly correlated throughout the dipole’s lifetime,which can be a useful criterion for judging if two eddies are a dipole. 展开更多
关键词 South China Sea(SCS) dipole eddy dipole lifetime wind stress work
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Ultra-low dose computed tomography chest vs chest radiography in paediatric primary ciliary dyskinesia:A prospective study
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作者 Michael G Waldron Patrick W O'Regan +13 位作者 Michael Lane Sahil S Shet Eid Kakish Fiachra Moloney Niamh Moore Mary Jane Murphy Louise Beagan Barry J Plant David Mullane Muireann Ni Chroinin David J Ryan Kevin O'Regan Stephen P Power Michael M Maher 《World Journal of Radiology》 2025年第8期64-73,共10页
BACKGROUND Primary ciliary dyskinesia(PCD)is a rare condition characterised by dysmotile,immotile,or absent cilia.As a result of the impairment in respiratory mucociliary clearance,patients with PCD typically develop ... BACKGROUND Primary ciliary dyskinesia(PCD)is a rare condition characterised by dysmotile,immotile,or absent cilia.As a result of the impairment in respiratory mucociliary clearance,patients with PCD typically develop neonatal respiratory distress,nasal congestion,otitis media and recurrent respiratory infections leading to bronchiectasis and structural lung changes.These changes have been shown by chest computed tomography(CT)to develop in infancy and early childhood.Recent development and refinement of radiation-reducing CT techniques have allowed significant radiation dose reductions,with chest CT doses now in the range of chest radiography(CR).AIM To evaluate the efficacy of ultra-low dose CT(ULDCT)chest in identifying pulmonary changes within a PCD paediatric patient cohort.METHODS Paediatric patients with PCD who presented for routine clinical outpatient follow-up within the study period,were eligible for inclusion in the study.ULDCT and CR were performed on these patients and the results compared.Comparison metrics included radiation dose,subjective and objective image quality and disease severity.RESULTS Six paediatric patients(mean age 9 years)underwent clinically indicated ULDCT chest examinations and CR for surveillance of their PCD.The mean effective dose was 0.08±0.02 mSv,a dose that approximates that of a frontal and lateral chest radiograph.The average Brody II score across the entire cohort was 12.92,with excellent interrater reliability and intra-class correlation coefficient(ICC)of 0.98.The average Chrispin-Norman score on CR was 1 with excellent inter-rater reliability and ICC of 0.92.CONCLUSION ULDCT demonstrates superior diagnostic capabilities,minimal radiation dose penalty,and high interobserver reliability in comparison to CR.Thus,we advocate for ULDCT to be the preferred modality for surveillance imaging in paediatric PCD. 展开更多
关键词 Primary ciliary dyskinesia Ultra-low dose computed tomography Chest radiography Radiation dose Image quality
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Enhanced photoelectric and thermoelectric coupling factor in BiMn_(2)O_(5) ferroelectric film
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作者 Aohan Xu Chong Guo +2 位作者 Weiqi Qian Chris R.Bowen Ya Yang 《Advanced Powder Materials》 2025年第1期74-82,共9页
Ferroelectric film materials have attracted significant interest due to their potential for harvesting various forms ofclean energy from natural environmental sources.However,the photoelectric performance of these mat... Ferroelectric film materials have attracted significant interest due to their potential for harvesting various forms ofclean energy from natural environmental sources.However,the photoelectric performance of these materials isfrequently constrained by heat generation during light absorption,resulting in significant thermal losses.Most offerroelectric films produce photocurrent and thermocurrent with opposite polarity,thus weakening the coupledphoto-thermoelectric output of the devices.Here we report on a LaNiO_(3)/BiMn_(2)O_(5)(BMO)/ITO ferroelectric film toproduce photocurrent and thermocurrent with the same polarity.The polarity of the photocurrent generated bythe BMO film is shown to be determined solely by the direction of spontaneous polarization,overcoming thedetrimental effect of Schottky barrier for energy harvesting in device.We propose a new strategy to enhance thecoupling factor,thereby offering valuable new insights for optimizing the utilization of ferroelectric materials inboth light and heat energy applications. 展开更多
关键词 Photo-thermoelectric Current polarity Coupling enhancement FERROELECTRIC Coupling factor
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光合作用系统模型与作物高光效改良 被引量:7
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作者 刘扶桑 宋青峰 +2 位作者 于桂朝 毛林雄 朱新广 《生命科学》 CSCD 2024年第9期1123-1140,共18页
提高光合效率是提高作物产量的有效手段。然而光合系统的复杂性使得单纯利用遗传手段鉴定提高光合效率的有效靶点无论从时间上还是从经济上成本都极高。构建并利用多尺度光合系统成为当前鉴定控制光合效率核心靶点的重要手段。本文回顾... 提高光合效率是提高作物产量的有效手段。然而光合系统的复杂性使得单纯利用遗传手段鉴定提高光合效率的有效靶点无论从时间上还是从经济上成本都极高。构建并利用多尺度光合系统成为当前鉴定控制光合效率核心靶点的重要手段。本文回顾了近年来光合系统模型的主要研究进展和主要应用实例,并进一步探讨了提高作物产量的光合作用系统模型未来的发展和应用方案。 展开更多
关键词 光合作用 光能利用效率 系统模型 数字植物 产量
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Quantifying source-sink relationships in leaf-color modified rice genotypes during grain filling 被引量:1
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作者 Zhenxiang Zhou Paul CStruik +4 位作者 Junfei Gu Peter E.L.van der Putten Zhiqin Wang Jianchang Yang Xinyou Yin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期2923-2940,共18页
Leaf-color modification can affect canopy photosynthesis,with potential effects on rice yield and yield components.Modulating source-sink relationships through crop management is often used to improve crop productivit... Leaf-color modification can affect canopy photosynthesis,with potential effects on rice yield and yield components.Modulating source-sink relationships through crop management is often used to improve crop productivity.This study investigated whether and how modifying leaf color alters source-sink relationships and whether current crop cultivation practices remain applicable for leaf-color modified genotypes.Periodically collected data of total biomass and nitrogen(N)accumulation in rice genotypes of four genetic backgrounds and their leaf-color modified variants(greener or yellower)were analyzed,using a recently established modelling method to quantify the source-sink(im)balance during grain filling.Among all leaf-color variants,only one yellower-leaf variant showed a higher source capacity than its normal genotype.This was associated with greater post-flowering N-uptake that prolonged the functional leaf-N duration,and this greater post-flowering N-uptake was possible because of reduced pre-flowering N-uptake.A density experiment showed that current management practices(insufficient planting density accompanied by abundant N application)are unsuitable for the yellower-leaf genotype,ultimately limiting its yield potential.Leaf-color modification affects source-sink relationships by regulating the N trade-off between pre-and post-flowering uptake,as well as N translocation between source and sink organs.To best exploit leaf-color modification for improving crop productivity,adjustments of crop management practices are required. 展开更多
关键词 source-sink relationship biomass nitrogen Oryza sativa leaf-color modification
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极端干旱区苏干湖湿地植被分类与变化分析 被引量:1
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作者 张腾 苗运法 +2 位作者 邹亚国 张孜越 冯国平 《中国沙漠》 CSCD 北大核心 2024年第4期81-90,共10页
湿地生物多样性极为丰富,湿地植被作为该生态系统中的核心部分,在维持系统稳定性和多功能性方面具有重要作用,掌握湿地植被类型与分布特征对生物多样性保护极其重要。然而,受湿地植被群落信息缺乏和遥感分辨率等因素的影响,对干旱区湿... 湿地生物多样性极为丰富,湿地植被作为该生态系统中的核心部分,在维持系统稳定性和多功能性方面具有重要作用,掌握湿地植被类型与分布特征对生物多样性保护极其重要。然而,受湿地植被群落信息缺乏和遥感分辨率等因素的影响,对干旱区湿地植被分类的研究存在明显不足。选择中国西北极端干旱区柴达木盆地北部的苏干湖湿地作为研究对象,以116个野外植被调查点以及626个无人机影像植被样本点数据为基础,选择Sentinel-1合成孔径雷达数据(Synthetic Aperture Radar,SAR)和Sentinel-2光学遥感数据(MultiSpectral Instrument,MSI)构建新的遥感特征数据库,运用随机森林算法进行苏干湖湿地植被的分类与制图。结果表明:(1)SAR数据和MSI数据的结合使用能够提高湿地植被分类的精度,2019、2020、2021、2022、2023年湿地植被分类结果总体精度均超过0.81,Kappa系数分别为0.82、0.84、0.86、0.82、0.82。(2)2019—2023年苏干湖湿地面积总体呈稳定状态,植被分布面积为783.90km^(2)。芦苇(Phragmites australis)群落面积增加了28.49 km^(2),赖草(Leymus secalinus)群落面积增加了27.21 km^(2),而水麦冬(Triglochin palustre)、沼泽荸荠(Eleocharis palustris)群落面积减少了64.49 km^(2)。初步认为径流增加和禁牧政策是湿地植被分布变化的重要原因。 展开更多
关键词 遥感监测 干旱区 苏干湖湿地 随机森林 植被分类
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Intelligent Recognition Using Ultralight Multifunctional Nano‑Layered Carbon Aerogel Sensors with Human‑Like Tactile Perception 被引量:4
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作者 Huiqi Zhao Yizheng Zhang +8 位作者 Lei Han Weiqi Qian Jiabin Wang Heting Wu Jingchen Li Yuan Dai Zhengyou Zhang Chris RBowen Ya Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期172-186,共15页
Humans can perceive our complex world through multi-sensory fusion.Under limited visual conditions,people can sense a variety of tactile signals to identify objects accurately and rapidly.However,replicating this uniq... Humans can perceive our complex world through multi-sensory fusion.Under limited visual conditions,people can sense a variety of tactile signals to identify objects accurately and rapidly.However,replicating this unique capability in robots remains a significant challenge.Here,we present a new form of ultralight multifunctional tactile nano-layered carbon aerogel sensor that provides pressure,temperature,material recognition and 3D location capabilities,which is combined with multimodal supervised learning algorithms for object recognition.The sensor exhibits human-like pressure(0.04–100 kPa)and temperature(21.5–66.2℃)detection,millisecond response times(11 ms),a pressure sensitivity of 92.22 kPa^(−1)and triboelectric durability of over 6000 cycles.The devised algorithm has universality and can accommodate a range of application scenarios.The tactile system can identify common foods in a kitchen scene with 94.63%accuracy and explore the topographic and geomorphic features of a Mars scene with 100%accuracy.This sensing approach empowers robots with versatile tactile perception to advance future society toward heightened sensing,recognition and intelligence. 展开更多
关键词 Multifunctional sensor Tactile perception Multimodal machine learning algorithms Universal tactile system Intelligent object recognition
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得不偿失:序贯决策中的短视风险漠视
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作者 陈志琴 马家涛 张雪婷 《心理科学进展》 CSSCI CSCD 北大核心 2024年第12期1980-1989,共10页
在日常生活和企业经营中,人们常常因忽视潜在的“高概率、大损失”风险而导致无法挽回的后果。为探究这一现象背后的科学问题,本研究构想首次提出了“短视风险漠视”这一新概念。具体而言,该概念指的是决策者在进行多轮相同或相似决策时... 在日常生活和企业经营中,人们常常因忽视潜在的“高概率、大损失”风险而导致无法挽回的后果。为探究这一现象背后的科学问题,本研究构想首次提出了“短视风险漠视”这一新概念。具体而言,该概念指的是决策者在进行多轮相同或相似决策时,由于短视评估和认知局限,难以准确意识到或评估各决策间的关联性,从而在单轮决策中追求当前增益目标而牺牲全局最优目标,并逐渐忽视长期风险的现象。因此,短视风险漠视态度可以视为序贯决策中的一种特定短视风险态度。序贯决策是指个体、群体或组织为实现最优总目标,按时序进行多次决策,且每次决策相关联的动态决策过程。尽管现实中的决策多为序贯决策,但当前行为决策研究主要集中于单次决策,很少探讨个体在序贯决策中的真实行为模式,这限制了过往研究对短视风险漠视现象的关注与探索。针对这一局限,本研究构想旨在基于序贯决策视角,揭示短视风险漠视现象,明确其表现规律与主要特点。此外,本研究构想还将开发一个特定的研究范式来测量短视风险漠视态度,并从决策过程和决策目标两个维度探究其形成机制。研究成果有望补充和拓展行为决策研究,并为未来序贯决策支持系统的开发提供理论基础。 展开更多
关键词 短视风险漠视 序贯决策 决策过程 决策目标
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The use of fluoroscopy for detecting hypertensive lung edema due to prosthetic valve dysfunction: a case report
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作者 Yusuf Kantar Necmi Baykan 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第4期313-315,共3页
Heart valve diseases affect more than one hundred million people around the world,which are a serious cause of illness and mortality.[1]Among the valve diseases,mitral valve insufficiency ranks second in the list of v... Heart valve diseases affect more than one hundred million people around the world,which are a serious cause of illness and mortality.[1]Among the valve diseases,mitral valve insufficiency ranks second in the list of valve diseases requiring surgical repair in Europe.[2]Prosthetic valve replacement is the standard treatment in cases where repair is not sufficient for valve diseases.[3]Mechanical and bioprosthetic valves can be preferred for replacement,mechanical valves are more durable and require lifelong use of anticoagulants.The disadvantage of bioprosthetic valves is early degeneration,and infective reoperation is required due to the formation of endocarditis.[4-5]The risk of thromboembolism,lifetime anticoagulant use and complications related to anticoagulation remain disadvantages of valve surgery.[3]The most important complication requiring urgent intervention is valve dysfunction due to thrombosis.It usually occurs due to inappropriate use of the anticoagulants.[6]Surgical treatment is used for severe obstructions,such as thrombi larger than 10 mm.Thrombolytic therapy can be applied in small thrombi and in cases where surgical intervention is risky. 展开更多
关键词 VALVE DISADVANTAGE LIFETIME
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Oxidative Stress in Collegiate Cross Country Skiers in Mid- and Post-Seasons
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作者 Scott P. Jerome Kriya L. Dunlap +4 位作者 Ava M. Parrish Matthew L. Lowman Emily M. Shipman Lawrence K. Duffy Arleigh J. Reynolds 《Journal of Biosciences and Medicines》 2024年第5期99-110,共12页
Purpose: The oxidative stress (OS) hypothesis of overtraining syndrome argues that increased production of free radicals through exercise cause muscle fatigue and damage resulting in lower athletic performance. Severa... Purpose: The oxidative stress (OS) hypothesis of overtraining syndrome argues that increased production of free radicals through exercise cause muscle fatigue and damage resulting in lower athletic performance. Several studies have investigated OS immediately before and after exercise bouts in a training macrocycle. Our study aimed to compare OS of endurance athletes between a competition macrocycle and the immediate post-season recovery macrocycle. In addition, we aimed to identify athletes who experienced an unexplainable drop in athletic performance during the competition season in order to compare their OS to those who experienced no drop in performance. Methods: Fifteen members of the University of Alaska Fairbanks cross country ski team volunteered for this study. Blood samples were taken in early February (“mid-season”) and late April (“post-season”). Participants completed questionnaires regarding physical activity and athletic performance at the time of the blood draws. Plasma was analyzed for 4-hydroxynonenal<sup> </sup>(HNE), nitrotyrosine,<sup> </sup>nitric oxide (NOX), and superoxide dismutase (SOD). Significance was determined by Wilcoxon and Mann-Whitney tests. Results: Participants displayed significantly higher (p Conclusion: Signs of oxidative stress and mitigation during the post-season recovery macrocycle were higher in athletes who reported experiencing a drop in athletic performance during the competition season macrocycle. 展开更多
关键词 Oxidative Stress 4-HYDROXYNONENAL Superoxide Dismutase Athletic Performance Training Macrocycle
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Antimicrobial Activity of Some Commercial Toothpastes and Antibiotics on Two Oral Pathogenic Bacteria—An in-Vitro Study
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作者 Abubaker Elrotob Idris Kabalci 《Journal of Biosciences and Medicines》 2024年第3期168-181,共14页
Oral health problems such as periodontal diseases, dental caries, and endodontic infections have a significant negative impact on oral health and impose a substantial financial burden on the global population. The pre... Oral health problems such as periodontal diseases, dental caries, and endodontic infections have a significant negative impact on oral health and impose a substantial financial burden on the global population. The prevalence of these issues is increasing due to the buildup of bacterial plaque and the growing resistance of bacteria to antimicrobial treatments. The aims of this study to evaluate the anti-bacterial activity of four types of antibiotics (Amoxicillin, Augmentin, Azithromycin and Metronidazole) and four types of toothpastes (Sensodyne, ipana, denta and cariax Gingival Kin) on two oral pathogenic bacteria (Streptococcus mutans and Staphylococcus epidermidis). Bacterial samples of previously isolated Streptococcus mutans and Staphylococcusepidermidis were used as test organisms and the Kirby-Bauer disc diffusion method was employed to assess the antibacterial efficacy of various antibiotics and evaluate the impact of different toothpastes using a filter paper disc agar measurement technique. Each filter disc was saturated with toothpaste solution in a test tube for approximately 30 to 40 seconds, after which they were placed on Mueller-Hinton broth bacterial cultures in petri dishes. These Petri dishes were then incubated at 37°C for 24 hours, and the clear zone’s diameter (inhibition zone in mm) was subsequently measured and the results were recorded. The results demonstrated that Sensodyne toothpaste and Metronidazole antibiotic were ineffective against both types of bacteria, while Augmentin and Amoxicillin were effective by high diameter inhibition zones of growth against S. mutans and Azithromycine against S. epidermidis. Also Ipana, Denta, and Cariax Gingival Kin toothpastes exhibited a moderate effect against the two bacteria. This study suggests that certain antibiotics and toothpastes can effectively inhibit the growth of harmful oral bacteria, but not all of them are effective. 展开更多
关键词 Antibacterial Effect ANTIBIOTICS Toothpastes Streptococcus mutans Staphylococcus epidermidis
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Mitogenomics clarifes the position of the Nearctic magpies (Pica hudsonia and Pica nuttalli) within the Holarctic magpie radiation
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作者 Alexey P.Kryukov Kirill A.Kryukov +2 位作者 Kathleen Collier Bohao Fang Scott V.Edwards 《Current Zoology》 SCIE CAS CSCD 2024年第5期618-630,共13页
Partial separation of a peripheral population may lead to its divergence and,potentially,speciation due to genetic drift followed by selection and geographic isolation.This process may cause taxonomic uncertainty beca... Partial separation of a peripheral population may lead to its divergence and,potentially,speciation due to genetic drift followed by selection and geographic isolation.This process may cause taxonomic uncertainty because reproductive isolation in allopatry cannot be verifed directly.The two Nearctic allopatric species of magpies(Aves,Corvidae:Pica)serve as a good example of these problems.The Black-billed magpie Pica hudsonia is widely distributed in North America,whereas the Yellow-billed Magpie Pica nuttalli is endemic to a restricted range in California.Their relationships with Palearctic species have been little studied.We obtained complete mitochondrial genomes of both Nearctic magpie species,along with the Eurasian Magpie(Pica pica)and the Oriental Magpie(Pica serica),20 mitogenomes in total.Phylogenetic analysis reveals a basal position of P.serica,and P.pica as a sister clade to the two Nearctic species.P.hudsonia and P.nuttalli form reciprocal monophyletic subclades,showing recent divergence between and within them.Our data show that the Nearctic magpie lineage diverged from the common ancestor with P.pica,with a single migration wave via the Beringia.Within the Nearctic,we hypothesize a peripatric mode of speciation among Pica taxa due to the divergence and separation of the small marginal population in California below the Sierra-Nevada mountains.Diversifying amino acid substitutions in ND4-ND5-ND6 genes along the branch leading to the New World clade may indicate selection for heat-tolerance.Considering the clear phenotypic differences between P.hudsonia and P.nuttalli,our data,showing their reciprocal monophylies and genetic distinctness,is consistent with the two-species taxonomy. 展开更多
关键词 Corvidae mitochondrial genome peripatric speciation reciprocal monophyly Sierra Nevada biogeographic barrier
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