期刊文献+
共找到660篇文章
< 1 2 33 >
每页显示 20 50 100
Influences of the Clearness Index on UV Solar Radiation for Two Locations in the Tibetan Plateau——Lhasa and Haibei 被引量:3
1
作者 胡波 王跃思 刘广仁 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第5期885-896,共12页
Ultraviolet (UV) solar radiation has a significant influence on human health, the environment and climate. A series of measurements, including UV radiation (290 400 nm) and global solar radiation (Rs), were cont... Ultraviolet (UV) solar radiation has a significant influence on human health, the environment and climate. A series of measurements, including UV radiation (290 400 nm) and global solar radiation (Rs), were continuously recorded from August 2004 at the Lhasa and Haibei sites on the Tibetan Plateau. Both observation sites' altitudes are above 3000 m and have similar meteorological conditions. The data from 2005 2006 was used to identify the varying characteristics of UV radiation. It's relation to the clearness index Ks, the relative optical mass mr, and Rs were established. The annual mean values of total daily UV radiation are 0.92 and 0.67 MJ m^-2 at Lhasa and Haibei, respectively. The UV radiation in Lhasa represented 4.6% of the global solar radiation while in Haibei this percentage was 4.2%. In the case of clear days (Ks 〉 0.8), these percentages ranged between 4.0% and 4.5% in Lhasa and between 5.1% and 5.5% in Haibei. In the case of cloudy days (Ks 〈 0.4), these percentages ranged from 4.4% to 6.8% in Lhasa and from 5.1% to 5.5% in Haibei. The maximum values of UV radiation for each relative optical mass diminished exponentially with mr. Thus, for Lhasa and Haibei, UV=46.25mr-129, and UV=51.76mr-142, respectively. The results of this study can be used to obtain more UV radiation data for the study of UV climate characteristics, the effects of UV on ecological processes and the feedback of the thinning of the stratospheric ozone, from more routine measurements Rs data. 展开更多
关键词 ultraviolet radiation clearness index Tibetan plateau
下载PDF
Estimation of Global Solar Radiation Using Clearness Index and Cloud Transmittance Factor at Trans-Himalayan Region in Nepal 被引量:1
2
作者 Khem N. Poudyal Binod K. Bhattarai +1 位作者 Balkrishna Sapkota Berit Kjeldstad 《Energy and Power Engineering》 2012年第6期415-421,共7页
This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Mete... This paper presents the global solar radiation (GSR) and cloud transmittance factor (cf) measured at the horizontal surface over a period of one year from 2009 to 2010 using CMP6 Pyranometer and NILUUV Irradiance Meter at Lukla (Latitude 26.69oN,Longitude 86.73?E and Altitude 2850 m) in the foothills of the Mt Everest (8850 m high). Monthly and seasonal variations of global solar radiation as well as correlation between clearness index and cloud transmittance factor at Lukla are presented. The annual average daily global solar radiation is about 3.83 kWh/sq·m/day which is sufficient to promote solar active and passive energy technology at high mountain terrain where there is no other viable alternative sources of energy. The maximum and minimum global solar radiation of 5.33 and 2.08 kWh/sq·m/day is recorded in April and September 2010 respectively. The seasonal variation of solar energy is about 2.87 kWh/sq·m/day and 4.83 kWh/sq·m/day in summer and spring respectively which is not in line with the general trend. The coefficient of determination (R2) between cloud transmittance factor (cf) and clearness factor (K) is found to be 0.97. This novel result can be utilized to estimate the global solar radiation at the horizontal surface where K and cf are available. 展开更多
关键词 Global Solar Radiation SEASONAL Variation CLOUD TRANSMITTANCE FACTOR clearness Index Coefficient of Determination High HIMALAYA Region
下载PDF
Classification of Hourly Clearness Index of Solar Radiation in the District of Yamoussoukro
3
作者 Siaman Paule Carine Yeboua Yao N’Goran Kouakou Konan 《Energy and Power Engineering》 2019年第5期220-231,共12页
The exploitation of systems using solar energy as a source of energy is not fluctuations free because of short passage of clouds on solar radiation. The amplitude, the persistence and the frequency of these fluctuatio... The exploitation of systems using solar energy as a source of energy is not fluctuations free because of short passage of clouds on solar radiation. The amplitude, the persistence and the frequency of these fluctuations should be analyzed with appropriate tools, instead of focusing on their location over time. The analysis of these fluctuations should use the instantaneous clearness index whose distribution is given as a first approximation which is independent not only of the season but also of the site. It is important to evaluate the potential solar energy in a region. Indeed such evaluation helps the decision-makers in their reflections on agricultural or photovoltaic solar projects. Then this study was conducted for a predictive purpose. The method used in our work combines the classification method which is the hierarchical ascending classification and two partitioning methods, the principal component?analysis and the K-means method. The partitioning method enabled to?achieve a number of well-known situations (in advance) that are representative of the day. The study was based on the data of a climatic weather station in the district of Yamoussoukro located in the center region of C&ocirc;te d’Ivoire during the 2017 year. Using the clearness index, the study allowed the classification of the solar radiation in the region. Thus, it showed that only 346 days of the 365 days in 2017 were classified (95%). We identified three clusters of days, the cloudy sky (29%), the partly cloudy sky?(32%) and the clear sky (39%). The statistical tests used for the characterization?of these clusters will be detailed in a future study. 展开更多
关键词 clearness Index HIERARCHICAL Clustering Principal Component Analysis K-MEANS Method CLASSIFICATION
下载PDF
Estimation of Daily Global Solar Radiation with Different Sunshine-Based Models for Some Burundian Stations
4
作者 Mathias Bashahu Gratien Ndacayisaba 《Energy and Power Engineering》 2024年第1期1-20,共20页
Sunshine duration (S) based empirical equations have been employed in this study to estimate the daily global solar radiation on a horizontal surface (G) for six meteorological stations in Burundi. Those equations inc... Sunshine duration (S) based empirical equations have been employed in this study to estimate the daily global solar radiation on a horizontal surface (G) for six meteorological stations in Burundi. Those equations include the Ångström-Prescott linear model and four amongst its derivatives, i.e. logarithmic, exponential, power and quadratic functions. Monthly mean values of daily global solar radiation and sunshine duration data for a period of 20 to 23 years, from the Geographical Institute of Burundi (IGEBU), have been used. For any of the six stations, ten single or double linear regressions have been developed from the above-said five functions, to relate in terms of monthly mean values, the daily clearness index () to each of the next two kinds of relative sunshine duration (RSD): and . In those ratios, G<sub>0</sub>, S<sub>0 </sub>and stand for the extraterrestrial daily solar radiation on a horizontal surface, the day length and the modified day length taking into account the natural site’s horizon, respectively. According to the calculated mean values of the clearness index and the RSD, each station experiences a high number of fairly clear (or partially cloudy) days. Estimated values of the dependent variable (y) in each developed linear regression, have been compared to measured values in terms of the coefficients of correlation (R) and of determination (R<sub>2</sub>), the mean bias error (MBE), the root mean square error (RMSE) and the t-statistics. Mean values of these statistical indicators have been used to rank, according to decreasing performance level, firstly the ten developed equations per station on account of the overall six stations, secondly the six stations on account of the overall ten equations. Nevertheless, the obtained values of those indicators lay in the next ranges for all the developed sixty equations:;;;, with . These results lead to assert that any of the sixty developed linear regressions (and thus equations in terms of and ), fits very adequately measured data, and should be used to estimate monthly average daily global solar radiation with sunshine duration for the relevant station. It is also found that using as RSD, is slightly more advantageous than using for estimating the monthly average daily clearness index, . Moreover, values of statistical indicators of this study match adequately data from other works on the same kinds of empirical equations. 展开更多
关键词 clearness Index Two Kinds of Relative Sunshine Duration Ångström-Prescott Linear Model and Four Derivatives Statistical Tests Six Burundian Stations
下载PDF
Metastatic clear cell sarcoma of the pancreas:A rare case report 被引量:10
5
作者 Yu-Jing Liu Chen Zou Yong-You Wu 《World Journal of Clinical Cases》 SCIE 2024年第8期1448-1453,共6页
BACKGROUND Clear cell sarcoma(CCS)is a rare soft-tissue sarcoma.The most common metastatic sites for CCS are the lungs,bones and brain.CCS is highly invasive and mainly metastasizes to the lung,followed by the bone an... BACKGROUND Clear cell sarcoma(CCS)is a rare soft-tissue sarcoma.The most common metastatic sites for CCS are the lungs,bones and brain.CCS is highly invasive and mainly metastasizes to the lung,followed by the bone and brain;however,pancreatic metastasis is relatively rare.CASE SUMMARY We report on a rare case of CCS with pancreatic metastasis in a 47-year-old man.The patient had a relevant medical history 3 years ago,with abdominal pain as the main clinical manifestation.No abnormalities were observed on physical examination and the tumor was found on abdominal computed tomography.Based on the medical history and postoperative pathology,the patient was diagnosed with CCS with pancreatic metastasis.The patient was successfully treated with surgical interventions,including distal pancreatectomy and sple-nectomy.CONCLUSION This report summarizes the available treatment modalities for CCS and the importance of regular postoperative follow-up for patients with CCS. 展开更多
关键词 Clear cell sarcoma PANCREAS METASTASIS FOLLOW-UP Case report
下载PDF
Neural stem cell-derived exosomes promote mitochondrial biogenesis and restore abnormal protein distribution in a mouse model of Alzheimer's disease 被引量:1
6
作者 Bo Li Yujie Chen +10 位作者 Yan Zhou Xuanran Feng Guojun Gu Shuang Han Nianhao Cheng Yawen Sun Yiming Zhang Jiahui Cheng Qi Zhang Wei Zhang Jianhui Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1593-1601,共9页
Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheime... Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheimer’s disease affects the entire brain,further research is needed to elucidate alterations in mitochondrial metabolism in the brain as a whole.Here,we investigated the expression of several important mitochondrial biogenesis-related cytokines in multiple brain regions after treatment with neural stem cell-derived exosomes and used a combination of whole brain clearing,immunostaining,and lightsheet imaging to clarify their spatial distribution.Additionally,to clarify whether the sirtuin 1(SIRT1)-related pathway plays a regulatory role in neural stem cell-de rived exosomes interfering with mitochondrial functional changes,we generated a novel nervous system-SIRT1 conditional knoc kout AP P/PS1mouse model.Our findings demonstrate that neural stem cell-de rived exosomes significantly increase SIRT1 levels,enhance the production of mitochondrial biogenesis-related fa ctors,and inhibit astrocyte activation,but do not suppress amyloid-βproduction.Thus,neural stem cell-derived exosomes may be a useful therapeutic strategy for Alzheimer’s disease that activates the SIRT1-PGC1αsignaling pathway and increases NRF1 and COXIV synthesis to improve mitochondrial biogenesis.In addition,we showed that the spatial distribution of mitochondrial biogenesis-related factors is disrupted in Alzheimer’s disease,and that neural stem cell-derived exosome treatment can reverse this effect,indicating that neural stem cell-derived exosomes promote mitochondrial biogenesis. 展开更多
关键词 Alzheimer’s disease mitochondrial biogenesis neural stem cell-derived exosome SIRT1-PGC1α regional brain distribution whole brain clearing and imaging
下载PDF
Metastatic clear cell sarcoma of the pancreas:A sporadic cancer 被引量:1
7
作者 Vittorio Gebbia Carlo Carnaghi 《World Journal of Clinical Cases》 SCIE 2024年第18期3291-3294,共4页
Primary or secondary clear cell sarcoma of the pancreas is an exceedingly rare and aggressive disease.In addition to pathology,molecular analysis is pivotal in differential diagnosis,especially with malignant melanoma... Primary or secondary clear cell sarcoma of the pancreas is an exceedingly rare and aggressive disease.In addition to pathology,molecular analysis is pivotal in differential diagnosis,especially with malignant melanoma.A key aspect in identifying clear cell sarcoma is specific genetic alterations,notably the translocation of t(12;22)(q13;q13),a diagnostic hallmark of this sarcoma subtype,which is absent in malignant melanoma.Treatment of primary clear cell sarcoma of the pancreas is the same as that for adenocarcinoma. 展开更多
关键词 Clear cell sarcoma PANCREAS Rare cancer METASTATIC DIAGNOSIS
下载PDF
60kV联合深度学习重建算法在主动脉CT血管造影中的可行性研究
8
作者 李明昕 刘杰 +3 位作者 陈岩 高剑波 李国文 许晨思 《影像研究与医学应用》 2024年第6期62-64,共3页
目的:探讨60 kV联合基于深度学习的ClearInfinity(CI)重建算法在主动脉CT血管造影中的可行性。方法:收集2023年7—9月因主动脉疾病在郑州大学第一附属医院拟行主动脉CT血管造影(CTA)的受检者73例,按照随机数字表法分为A组(n=36)和B组(n=... 目的:探讨60 kV联合基于深度学习的ClearInfinity(CI)重建算法在主动脉CT血管造影中的可行性。方法:收集2023年7—9月因主动脉疾病在郑州大学第一附属医院拟行主动脉CT血管造影(CTA)的受检者73例,按照随机数字表法分为A组(n=36)和B组(n=37)。A组受检者采用100 kV行常规扫描和重建;B组受检者采用60 kV行CT扫描,再依据重建算法不同分为B1、B2、B3亚组,分别采用30%~90%(间隔30%)CI算法重建,比较各组受检者辐射剂量以及图像质量。结果:除A组和B1组的信噪比(SNR)值在降主动脉、髂总动脉外,其余各组间SNR值比较,差异有统计学意义(均P <0.05)。除A组和B1组在降主动脉层面外,其余各组间对比噪声比(CNR)值比较,差异有统计学意义(均P <0.05)。图像主观评分A组与B2组比较,差异无统计学意义(P> 0.05),A组、B1组和B3组主观评分比较,差异有统计学意义(P <0.05)。结论:对体重指数(BMI)<26 kg/m~2的正常体型受检者,采用60 kV行主动脉CTA能大幅降低辐射剂量,联合深度学习CI重建算法能显著降低图像噪声,改善图像质量以达到诊断需求。 展开更多
关键词 血管造影术 主动脉造影术 Clear Infinity算法 辐射剂量
下载PDF
Sacrificial piles as a countermeasure against local scour around underwater pipelines
9
作者 Forough Raeisi Seyed Mohammad Ali Zomorodiann +1 位作者 Masih Zolghadr Hazi Mohammad Azamathulla 《Water Science and Engineering》 EI CAS CSCD 2024年第2期187-196,共10页
Local scour around pipelines crossing rivers or in marine environments is a significant concern.It can lead to failure of the pipelines resulting in environmental side effects and economic losses.This study developed ... Local scour around pipelines crossing rivers or in marine environments is a significant concern.It can lead to failure of the pipelines resulting in environmental side effects and economic losses.This study developed an experimental method to reduce local scour around pipelines with a steady flow of clear water by installing cylindrical and cubical sacrificial piles.Three sizes of sacrificial piles were examined in a linear arrangement.Sacrificial piles were installed on the upstream side of the pipeline at three distances.Maximum scour depth reduction rates below the pipeline were computed.The results showed that sacrificial piles could protect a pipeline from local scour.A portion of scoured sediment around the sacrificial piles was deposited beneath the pipeline.This sediment accumulation reduced the scour depth beneath the pipeline.Analysis of the experimental results demonstrated that the size of piles(d),the spacing between piles,and the distance between the pipe and piles(Xp)were the variables that reduced the maximum scour beneath the pipeline with a diameter of D.For the piles with d=0.40D and 0.64D,X_(p)=4OD was the optimal distance to install a group of piles,and cubical piles could mitigate scour more effectively than cylindrical piles under similar conditions.For the piles with d=D,the greatest reduction in scour depth was achieved at X_(p)=50D with any desired spacings between piles,and cylindrical piles in this dimension could protect the pipeline against scour more effectively than cubical piles. 展开更多
关键词 Clear water River crossing pipeline Local scour Self-burial process Sediment transport
下载PDF
A"messenger zone hypothesis"based on the visual three-dimensional spatial distribution of motoneurons innervating deep limb muscles
10
作者 Chen Huang Shen Wang +3 位作者 Jin Deng Xinyi Gu Shuhang Guo Xiaofeng Yin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1559-1567,共9页
Coordinated contraction of skeletal muscles relies on selective connections between the muscles and multiple classes of the spinal motoneuro ns.Howeve r,current research on the spatial location of the spinal motoneuro... Coordinated contraction of skeletal muscles relies on selective connections between the muscles and multiple classes of the spinal motoneuro ns.Howeve r,current research on the spatial location of the spinal motoneurons innervating differe nt muscles is limited.In this study,we investigated the spatial distribution and relative position of different motoneurons that control the deep muscles of the mouse hindlimbs,which were innervated by the obturator nerve,femoral nerve,inferior gluteal nerve,deep pe roneal nerve,and tibial nerve.Locations were visualized by combining a multiplex retrograde tracking technique compatible with three-dimensional imaging of solvent-cleared o rgans(3DISCO)and 3-D imaging technology based on lightsheet fluorescence microscopy(LSFM).Additionally,we propose the hypothesis that"messenger zones"exist as interlaced areas between the motoneuron pools that dominate the synergistic or antagonist muscle groups.We hypothesize that these interlaced neurons may participate in muscle coordination as messenger neurons.Analysis revealed the precise mutual positional relationships among the many motoneurons that innervate different deep muscles of the mouse.Not only do these findings update and supplement our knowledge regarding the overall spatial layout of spinal motoneurons that control mouse limb muscles,but they also provide insights into the mechanisms through which muscle activity is coordinated and the architecture of motor circuits. 展开更多
关键词 3-D imaging MOTONEURONS multiple retrograde tracing muscle coordination skeletal muscle spatial distribution optical tissue clearing
下载PDF
Dynamic optimal allocation of energy storage systems integrated within photovoltaic based on a dual timescale dynamics model
11
作者 Kecun Li Zhenyu Huang +2 位作者 Youbo Liu Yaser Qudaih Junyong Liu 《Global Energy Interconnection》 EI CSCD 2024年第4期415-428,共14页
Energy storage systems(ESSs)operate as independent market participants and collaborate with photovoltaic(PV)generation units to enhance the flexible power supply capabilities of PV units.However,the dynamic variations... Energy storage systems(ESSs)operate as independent market participants and collaborate with photovoltaic(PV)generation units to enhance the flexible power supply capabilities of PV units.However,the dynamic variations in the profitability of ESSs in the electricity market are yet to be fully understood.This study introduces a dual-timescale dynamics model that integrates a spot market clearing(SMC)model into a system dynamics(SD)model to investigate the profit-aware capacity growth of ESSs and compares the profitability of independent energy storage systems(IESSs)with that of an ESS integrated within a PV(PV-ESS).Furthermore,this study aims to ascertain the optimal allocation of the PV-ESS.First,SD and SMC models were set up.Second,the SMC model simulated on an hourly timescale was incorporated into the SD model as a subsystem,a dual-timescale model was constructed.Finally,a development simulation and profitability analysis was conducted from 2022 to 2040 to reveal the dynamic optimal range of PV-ESS allocation.Additionally,negative electricity prices were considered during clearing processes.The simulation results revealed differences in profitability and capacity growth between IESS and PV-ESS,helping grid investors and policymakers to determine the boundaries of ESSs and dynamic optimal allocation of PV-ESSs. 展开更多
关键词 Optimal allocation Profitability analysis PHOTOVOLTAIC Energy storage system Dual timescale dynamics model Spot market clearing
下载PDF
Transforming Adolescent Smiles:Correcting Skeletal Mandibular Retrusion and Bimaxillary Protrusion with Clear Aligners
12
作者 Wen-jie FAN Jia-qi ZHANG +2 位作者 Jia-qi ZHAN Li HU Li-li CHEN 《Current Medical Science》 SCIE CAS 2024年第3期657-666,共10页
Maxillary protrusion combined with mandibular retraction is a highly prevalent but extremely complex maxillofacial deformity that can have a serious negative impact on patients’facial aesthetics and mental health.The... Maxillary protrusion combined with mandibular retraction is a highly prevalent but extremely complex maxillofacial deformity that can have a serious negative impact on patients’facial aesthetics and mental health.The traditional orthodontic treatment strategy often involves extracting 4 first premolars and conventional fixed techniques,combined with mini-implant screws,to retract the anterior teeth and improve facial protrusion.In recent years,an invisible orthodontic technique,without brackets,has become increasingly popular.However,while an invisible aligner has been used in some cases with reasonable results,there remain significant challenges in achieving a perfect outcome.This case report presents an adolescent patient with bimaxillary protrusion and mandibular retrognathia.Based on the characteristics of the invisible aligners and the growth characteristics of the adolescent’s teeth and jawbone,we designed precise three-dimensional tooth movement and corresponding resistance/over-correction for each tooth,while utilizing the patient’s jawbone growth potential to promote rapid development of the mandible,accurately and efficiently correcting bimaxillary protrusion and skeletal mandibular retrognathia.The patient’s facial aesthetics,especially the lateral morphology,have been greatly improved,and various aesthetic indicators have also shown significant changes,and to the patient’s great benefit,invasive mini-implant screws were not used during the treatment.This case highlights the advantages of using invisible aligners in adolescent maxillary protrusion combined with mandibular retraction patients.Furthermore,comprehensive and accurate design combined with good application of growth potential can also enable invisible orthodontic technology to achieve perfect treatment effects in tooth extractions,providing clinical guidance for orthodontists. 展开更多
关键词 mandibular retrusion esthetic orthodontic treatment clear aligners growth potential
下载PDF
Eureka lemon zinc finger protein ClDOF3.4 interacts with citrus yellow vein clearing virus coat protein to inhibit viral infection
13
作者 Ping Liao Ting Zeng +4 位作者 Mengyang Huangfu Cairong Zheng Jiequn Ren Changyong Zhou Yan Zhou 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1979-1993,共15页
Citrus yellow vein clearing virus(CYVCV)is a new citrus virus that has become an important factor restricting the development of China’s citrus industry,and the CYVCV coat protein(CP)is associated with viral pathogen... Citrus yellow vein clearing virus(CYVCV)is a new citrus virus that has become an important factor restricting the development of China’s citrus industry,and the CYVCV coat protein(CP)is associated with viral pathogenicity.In this study,the Eureka lemon zinc finger protein(ZFP)ClDOF3.4 was shown to interact with CYVCV CP in vivo and in vitro.Transient expression of ClDOF3.4 in Eureka lemon induced the expression of salicylic acid(SA)-related and hypersensitive response marker genes,and triggered a reactive oxygen species burst,ion leakage necrosis,and the accumulation of free SA.Furthermore,the CYVCV titer in ClDOF3.4 transgenic Eureka lemon plants was approximately 69.4%that in control plants 6 mon after inoculation,with only mild leaf chlorotic spots observed in those transgenic plants.Taken together,the results indicate that ClDOF3.4 not only interacts with CP but also induces an immune response in Eureka lemon by inducing the SA pathways.This is the first report that ZFP is involved in the immune response of a citrus viral disease,which provides a basis for further study of the molecular mechanism of CYVCV infection. 展开更多
关键词 citrus yellow vein clearing virus coat protein ClDOF3.4 plant immune response
下载PDF
Rehabilitation of Semi-Arid Grasslands through the Perennialization of Lots by Implementing Perennial Forage Exotic Grass
14
作者 Delfina Arancio Sidoti Juan Manuel Zeberio Guadalupe Peter 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第8期2115-2125,共11页
Argentina is the country with the highest proportion of arid and semi-arid ecosystems in Latin America.In the rangelands of Southwestern Buenos Aires(Patagones Department),there is a clear advancement of the agricultu... Argentina is the country with the highest proportion of arid and semi-arid ecosystems in Latin America.In the rangelands of Southwestern Buenos Aires(Patagones Department),there is a clear advancement of the agricultural frontier to the detriment of the native forest in this region.Due to rainfall variation and seed acquisition,Thinopyrum ponticum is cultivated as a forage perennial crop in this region.Our objective was to evaluate the performance of T.ponticum as a facilitating crop for the medium-term rehabilitation of natural grasslands in semi-arid areas.The working hypotheses were that:1)native perennial grass cover increases over the years and 2)diversity and specific richness of the vegetation are enhanced by the duration of Tall Wheatgrass implantation.Data were collected from commercial plots where T.ponticum was shown:recent implantation(5–8 years,RI);medium implantation(13–15 years,MI);and old implantation(20–22 years,OI).Thirty-four species were identified and classified into seven functional groups:Annual grasses,annual herbs,perennial herbs,exotic perennial herbs,perennial forage grasses,exotic perennial forage grasses,perennial forage exotic grasses,and nonforage perennial grasses.Thinopyrum ponticum’s total cover was between RI and OI.Total cover,species richness,and Shannon-Weaver diversity index showed no differences among treatments.Perennial forage grasses exhibited higher cover values in sites with greater implantation age and annual grasses showed the opposite response.Our results indicated that T.ponticum does not invade the sampled plots and enhances the colonization of the planted plots by perennial forage native species.However,even though the herbaceous cover had been recovered,the woody layer which could provide environmental services and specific values for conservation was not. 展开更多
关键词 Wheatgrass clearing vegetation MONTE Thinopyrum ponticum
下载PDF
Essential role of postoperative follow-up in the management of clear cell sarcoma
15
作者 Zi-Han Zhang Jin-Tao Guo +1 位作者 Ying Xie Si-Yu Sun 《World Journal of Clinical Cases》 SCIE 2024年第23期5299-5303,共5页
Clear cell sarcoma(CCS)is a rare melanocytic soft tissue sarcoma known for itspropensity to metastasize to the lymph nodes and typically has an unfavorableprognosis.Currently,surgical resection is the primary treatmen... Clear cell sarcoma(CCS)is a rare melanocytic soft tissue sarcoma known for itspropensity to metastasize to the lymph nodes and typically has an unfavorableprognosis.Currently,surgical resection is the primary treatment for localizedCCS,while radiotherapy and chemotherapy are preferred for metastatic cases.The roles of adjuvant chemotherapy,radiotherapy,and lymph node dissection arecontroversial.Although immunotherapy has emerged as a promising avenue inCCS treatment research,there are no established clinical standards for postoperativefollow-up.This editorial discusses a recent article by Liu et al,with afocus on current diagnostic modalities,treatment approaches,and the challengingprognosis associated with CCS.Our aim is to underscore the importance of longtermpatient follow-up in CCS management. 展开更多
关键词 Clear cell carcinoma DIAGNOSIS Treatment PROGNOSIS FOLLOW-UP
下载PDF
DNBP-CCA:A Novel Approach to Enhancing Heterogeneous Data Traffic and Reliable Data Transmission for Body Area Network
16
作者 Abdulwadood Alawadhi Mohd.Hasbullah Omar +3 位作者 Abdullah Almogahed Noradila Nordin Salman A.Alqahtani Atif M.Alamri 《Computers, Materials & Continua》 SCIE EI 2024年第5期2851-2878,共28页
The increased adoption of Internet of Medical Things (IoMT) technologies has resulted in the widespread use ofBody Area Networks (BANs) in medical and non-medical domains. However, the performance of IEEE 802.15.4-bas... The increased adoption of Internet of Medical Things (IoMT) technologies has resulted in the widespread use ofBody Area Networks (BANs) in medical and non-medical domains. However, the performance of IEEE 802.15.4-based BANs is impacted by challenges related to heterogeneous data traffic requirements among nodes, includingcontention during finite backoff periods, association delays, and traffic channel access through clear channelassessment (CCA) algorithms. These challenges lead to increased packet collisions, queuing delays, retransmissions,and the neglect of critical traffic, thereby hindering performance indicators such as throughput, packet deliveryratio, packet drop rate, and packet delay. Therefore, we propose Dynamic Next Backoff Period and Clear ChannelAssessment (DNBP-CCA) schemes to address these issues. The DNBP-CCA schemes leverage a combination ofthe Dynamic Next Backoff Period (DNBP) scheme and the Dynamic Next Clear Channel Assessment (DNCCA)scheme. The DNBP scheme employs a fuzzy Takagi, Sugeno, and Kang (TSK) model’s inference system toquantitatively analyze backoff exponent, channel clearance, collision ratio, and data rate as input parameters. Onthe other hand, the DNCCA scheme dynamically adapts the CCA process based on requested data transmission tothe coordinator, considering input parameters such as buffer status ratio and acknowledgement ratio. As a result,simulations demonstrate that our proposed schemes are better than some existing representative approaches andenhance data transmission, reduce node collisions, improve average throughput, and packet delivery ratio, anddecrease average packet drop rate and packet delay. 展开更多
关键词 Internet of Medical Things body area networks backoff period tsk fuzzy model clear channel assessment media access control
下载PDF
Shedding light on pancreatic metastasis of clear cell sarcoma:An exceptional journey
17
作者 Preeti Kumari Chaudhary Soochong Kim 《World Journal of Clinical Cases》 SCIE 2024年第25期5657-5661,共5页
This editorial comments on the study by Liu et al investigating pancreatic metastasis of clear cell sarcoma(CCS)published in the World Journal of Clinical Cases.CCS is a rare and aggressive melanocytic tumor,that typi... This editorial comments on the study by Liu et al investigating pancreatic metastasis of clear cell sarcoma(CCS)published in the World Journal of Clinical Cases.CCS is a rare and aggressive melanocytic tumor,that typically arises from tendons and aponeuroses of the limbs,and metastasizes to the lungs,bones,and brain.However,pancreatic metastasis has rarely been reported,presenting unique diagnostic and therapeutic challenges.Elucidating the clinical characteristics,imaging features,prognostic factors,and treatment outcomes of patients with pancreatic CCS metastasis is crucial.Surgery remains an effective management strategy for CCS.However,the high recurrence rate and low effectiveness of traditional adjuvant treatments necessitate a shift towards more personalized and targeted treatment plans.Research is needed to investigate and validate novel therapeutic approaches specifically tailored to the distinct genetic and molecular characteristics of rare malignancies like CCS.Additionally,the development of late metastases after a long disease-free interval is common in CCS patients.Therefore,routine postoperative surveillance for metastasis using computed tomography,magnetic resonance imaging,bone scans,and positron emission tomography scans is crucial.Moving forward,enhanced collaboration,investigation,and creative thinking among scientists,medical professionals,and legislators are essential to gain a deeper understanding of these rare presentations. 展开更多
关键词 Clear cell sarcoma PANCREAS METASTASIS DIAGNOSIS Treatment
下载PDF
Metastatic clear cell sarcoma of the pancreas:An overview
18
作者 Rachid Ait Addi 《World Journal of Clinical Cases》 SCIE 2024年第29期6262-6265,共4页
Clear cell sarcoma(CCS)is a rare soft-tissue sarcoma that accounts for less than 1%of all cases and was originally reported in 1965.The incidence of CCS is estimated to be approximately 0.014/100000 depending on the s... Clear cell sarcoma(CCS)is a rare soft-tissue sarcoma that accounts for less than 1%of all cases and was originally reported in 1965.The incidence of CCS is estimated to be approximately 0.014/100000 depending on the surveillance,epidemiology and end results databases.CCS is a highly invasive type that mainly metastasizes to the lungs,followed by the bones and brain;however,pancreatic metastasis is relatively rare.It has a high probability of recurrence or metastasis and has a poor prognosis with a high mortality rate.Finally,even after recovery,it is fundamental to keep regular postoperative follow-up for CCS patients. 展开更多
关键词 Clear cell sarcoma PANCREAS METASTASIS FOLLOW-UP Case report
下载PDF
上一页 1 2 33 下一页 到第
使用帮助 返回顶部