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Anterior mediastinal masses and thymic cysts
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作者 ÖnerÖzdemir 《World Journal of Clinical Cases》 SCIE 2025年第4期1-7,共7页
Cystic lesions of the anterior mediastinum in children suggest a well-known group of benign lesions that are comparatively frequent.Thymic cysts(TCs)are mostly positioned in the anterior mediastinum and some patients ... Cystic lesions of the anterior mediastinum in children suggest a well-known group of benign lesions that are comparatively frequent.Thymic cysts(TCs)are mostly positioned in the anterior mediastinum and some patients in the neck.Benign TCs classified as congenital intra-thoracic mesothelial cysts are commonly asymptomatic and have slight clinical significance.Multilocular TC,which can mimic another anterior mediastinal cystic tumor and is seen in adults,is more clinically important.It is a sporadic mediastinal lesion thought to arise in the course of acquired inflammation.Congenital mediastinal cysts represent 3%-6%of all mediastinal tumors and 10%-18%of radiologically reported mediastinal masses.Mediastinal TCs are uncommon and it is hard to know their true incidence.About 60%of cases with mediastinal TCs are asymptomatic,and the remainder of patients complains of nonspecific symptoms(e.g.,chest pain,dyspnea,or cough).The literature suggests that most cysts are benign,but an indefinite percentage may have a neoplastic process and result in significant compressive symptoms over time.Clinical symptoms of TCs vary depending on the location.In addition,frequent symptoms at the appearance of enlarged benign thymic and mediastinal cysts generally contain compressive symptoms(e.g.,respiratory distress,thymic pain,and symptoms related to Horner syndrome,hoarseness,dysphonia,dyspnea,orthopnea,wheezing,and fever).Many TCs have cystic density and a neat border and are simple to diagnose with radiological imaging.However,some TCs are hard to identify before surgery and may be misidentified as thymomas depending on their site and computed tomography results.Excision by thoracotomy,median sternotomy,or video-assisted techniques is essential for conclusive diagnosis,management,and abolition of relapse of anterior mediastinal masses and TCs.Histopathologic examination may be required after surgery.Considering the extent of the mass and the preliminary inability to make a definitive diagnosis,en bloc excision of the cyst was thought to be preferred to circumvent likely complications(e.g.,perforation,spillage of the contents,or incomplete excision). 展开更多
关键词 Mediastinal mass Thymic cyst Malignant tumor CYSTS THYMOMA Computer tomography
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Reading man皮瓣修复术治疗皮肤缺损的疗效观察
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作者 王鸣 严炜 +3 位作者 汤由之 朱喆辰 史京萍 马秀云 《临床皮肤科杂志》 CAS CSCD 北大核心 2024年第9期557-561,共5页
目的:探讨Reading man皮瓣修复术在全身不同部位皮肤缺损及其预防瘢痕增生的临床疗效。方法:回顾性分析2021年1月—2023年10月该科应用Reading man皮瓣修复术治疗全身不同部位皮肤软组织缺损的20例患者临床资料。结果:所有患者皮瓣均成... 目的:探讨Reading man皮瓣修复术在全身不同部位皮肤缺损及其预防瘢痕增生的临床疗效。方法:回顾性分析2021年1月—2023年10月该科应用Reading man皮瓣修复术治疗全身不同部位皮肤软组织缺损的20例患者临床资料。结果:所有患者皮瓣均成活。术后随访时间为3~24个月,所有皮瓣血运良好,色泽红润,质地柔软,外观适宜,局部皮肤张力较低,手术切口瘢痕增生不明显,切口周围软组织无明显形变,周围关节活动度正常。所有患者均恢复良好,疗效满意。结论:Reading man皮瓣特有的设计可以很好地解决全身多部位较大的皮肤软组织缺损,尤其在术中可以最大限度地减少正常皮肤的切除,术后外观、功能及皮肤瘢痕增生均有较满意的表现,且不存在自体皮移植带来的供皮区损伤。 展开更多
关键词 reading man皮瓣 皮瓣血运 张力 瘢痕增生
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Probabilistic analysis of tunnel face seismic stability in layered rock masses using Polynomial Chaos Kriging metamodel 被引量:2
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作者 Jianhong Man Tingting Zhang +1 位作者 Hongwei Huang Daniel Dias 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2678-2693,共16页
Face stability is an essential issue in tunnel design and construction.Layered rock masses are typical and ubiquitous;uncertainties in rock properties always exist.In view of this,a comprehensive method,which combines... Face stability is an essential issue in tunnel design and construction.Layered rock masses are typical and ubiquitous;uncertainties in rock properties always exist.In view of this,a comprehensive method,which combines the Upper bound Limit analysis of Tunnel face stability,the Polynomial Chaos Kriging,the Monte-Carlo Simulation and Analysis of Covariance method(ULT-PCK-MA),is proposed to investigate the seismic stability of tunnel faces.A two-dimensional analytical model of ULT is developed to evaluate the virtual support force based on the upper bound limit analysis.An efficient probabilistic analysis method PCK-MA based on the adaptive Polynomial Chaos Kriging metamodel is then implemented to investigate the parameter uncertainty effects.Ten input parameters,including geological strength indices,uniaxial compressive strengths and constants for three rock formations,and the horizontal seismic coefficients,are treated as random variables.The effects of these parameter uncertainties on the failure probability and sensitivity indices are discussed.In addition,the effects of weak layer position,the middle layer thickness and quality,the tunnel diameter,the parameters correlation,and the seismic loadings are investigated,respectively.The results show that the layer distributions significantly influence the tunnel face probabilistic stability,particularly when the weak rock is present in the bottom layer.The efficiency of the proposed ULT-PCK-MA is validated,which is expected to facilitate the engineering design and construction. 展开更多
关键词 Tunnel face stability Layered rock masses Polynomial Chaos Kriging(PCK) Sensitivity index Seismic loadings
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Text Difficulty,Working Memory Capacity and Mind Wandering During Chinese EFL Learners’Reading
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作者 Xianli GAO Li LI 《Chinese Journal of Applied Linguistics》 2024年第3期433-449,525,共18页
This experimental study investigated how text difficulty and different working memory capacity(WMC)affected Chinese EFL learners’reading comprehension and their tendency to engage in task-unrelated thoughts,that is,m... This experimental study investigated how text difficulty and different working memory capacity(WMC)affected Chinese EFL learners’reading comprehension and their tendency to engage in task-unrelated thoughts,that is,mind wandering(MW),in the course of reading.Sixty first-year university non-English majors participated in the study.A two-factor mixed experimental design of 2(text difficulty:difficult and simple)×2(WMC:high/large and low/small)was employed.Results revealed that 1)the main and interaction effects of WMC and text difficulty on voluntary MW were significant,whereas those on involuntary MW were not;2)while reading the easy texts,the involuntary MW of high-WMC individuals was less frequent than that of low-WMC ones,whereas while reading the difficult ones,the direct relationship between WMC and involuntary MW was not found;and that 3)high-WMC individuals had a lower overall rate of MW and better reading performance than low-WMC individuals did,but with increasing text difficulty,their rates of overall MW and voluntary MW were getting higher and higher,and the reading performance was getting lower and lower.These results lend support to WM theory and have pedagogical implications for the instruction of L2 reading. 展开更多
关键词 text difficulty working memory capacity reading mind wandering voluntary mind wandering involuntary mind wandering reading comprehension
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Extended reading板块教学设计
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作者 施晓明 《江苏教育》 2024年第15期35-38,共4页
根据《普通高中英语课程标准(2017年版2020修订)》(以下简称“新课标”),教师应引导学生广泛阅读,提升阅读能力,丰富语言、人文和科学知识,并拓展思维,增强审美、鉴赏和评价能力。广义的拓展阅读可在课堂内外开展;狭义的拓展阅读指基于... 根据《普通高中英语课程标准(2017年版2020修订)》(以下简称“新课标”),教师应引导学生广泛阅读,提升阅读能力,丰富语言、人文和科学知识,并拓展思维,增强审美、鉴赏和评价能力。广义的拓展阅读可在课堂内外开展;狭义的拓展阅读指基于单元主题,在课堂内进行的主题式拓展阅读,是对教材主阅读板块内容的延伸和内涵的拓展。[1]作为拓展阅读的素材,非故事类文本有助于学生拓宽知识面、增进对世界的认识。 展开更多
关键词 高中英语 Extended reading板块 深度学习 非故事类文本
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A Study on the Values and Strategies of English Picture Book Reading for Improving Pupils’ English Reading Literacy
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作者 MAI Yuxuan 《Sino-US English Teaching》 2024年第3期120-126,共7页
Reading is one of the core skills in English learning.It is indispensable for EFL learners to develop good English reading literacy in primary schools.English picture books are consistent with pupils’cognitive and th... Reading is one of the core skills in English learning.It is indispensable for EFL learners to develop good English reading literacy in primary schools.English picture books are consistent with pupils’cognitive and thinking modes,which is valuable to improve their English reading literacy.However,at present,most Chinese pupils have some problems in English reading.The paper aims at analyzing the current problems in Chinese pupils’English reading and digging out the values and strategies of English picture book reading,so as to stimulate their reading interests,cultivate their intercultural awareness,and improve their English reading literacy. 展开更多
关键词 English reading literacy English picture book reading VALUES STRATEGIES
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Solid pancreatic masses:What’s hidden beneath?Insights into rare pancreatic lesions
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作者 Daniel Vasile Balaban 《World Journal of Clinical Cases》 SCIE 2024年第29期6255-6257,共3页
The diagnostic approach to solid pancreatic masses has significantly evolved from the era when a focal pancreatic mass was almost synonymous to pancreatic ductal adenocarcinoma,to a wide spectrum of pancreatic lesions... The diagnostic approach to solid pancreatic masses has significantly evolved from the era when a focal pancreatic mass was almost synonymous to pancreatic ductal adenocarcinoma,to a wide spectrum of pancreatic lesions,some of which have good prognosis.With the advent of advanced diagnostic tools,particularly refined imaging and tissue acquisition techniques,a broader spectrum of differential diagnoses has been recognized,encompassing conditions ranging from neuroendocrine tumors or inflammatory masses,to rare entities like metastatic clear cell sarcoma or solitary fibrous tumors.We herein discuss case reports of some rare pancreatic lesions,which were diagnosed by combining clinical and imaging features and endoscopic ultrasound-guided tissue sampling and confirmed on surgical specimens.Further reports on these rare pancreatic tumors will contribute to a better understanding of their pathogenesis and effective management. 展开更多
关键词 Pancreatic mass PANCREAS METASTASIS Diagnosis Endoscopic ultrasound
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Study on the Influencing Factors of L2 Reading Ability and Its Regulation Strategies
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作者 MA Yuanxuan NI Jincheng 《Sino-US English Teaching》 2024年第1期19-25,共7页
This paper takes college students as research subjects to investigate the factors affecting L2 Reading ability and their regulation strategies through scale surveys.The findings are as follows:(1)Linguistic factors ha... This paper takes college students as research subjects to investigate the factors affecting L2 Reading ability and their regulation strategies through scale surveys.The findings are as follows:(1)Linguistic factors have significant impacts on L2 Reading ability,and the influence of non-linguistic factors,such as non-intellectual factors and cultural background knowledge,is also important;and(2)flexible use of reading regulation strategies according to the learning conditions(such as the information extraction strategy,the metacognitive reading regulation strategy,and the interactive reading strategy)can effectively improve learners’L2 Reading ability.The findings of this study have important theoretical and practical value for improving L2 learners’Reading ability. 展开更多
关键词 L2 reading ability influencing factors reading regulation strategies
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Standard Model Fermion Masses and Charges from Holographic Analysis
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作者 T. R. Mongan 《Journal of Modern Physics》 2024年第6期796-803,共8页
The Standard Model of particle physics involves twelve fundamental fermions, treated as point particles, in four charge states. However, the Standard Model does not explain why only three fermions are in each charge s... The Standard Model of particle physics involves twelve fundamental fermions, treated as point particles, in four charge states. However, the Standard Model does not explain why only three fermions are in each charge state or account for neutrino mass. This holographic analysis treats charged Standard Model fermions as spheres with mass 0.187 g/cm<sup>2</sup> times their surface area, using the proportionality constant in the holographic relation between mass of the observable universe and event horizon radius. The analysis requires three Standard Model fermions per charge state and relates up quark and down quark masses to electron mass. Holographic analysis specifies electron mass, to six significant figures, in terms of fundamental constants α,ℏ,G,Λ and Ω Λ . Treating neutrinos as spheres and equating electron neutrino energy density with cosmic vacuum energy density predicts neutrino masses consistent with experiment. 展开更多
关键词 Electron mass Up Quark mass Down Quark mass Neutrino masses
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The Reading Movement in Shanghai,China in the Late 1950s
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作者 LIU Hao JING Huilan 《International Relations and Diplomacy》 2024年第2期86-90,共5页
At the end of the 1950s,Shanghai region of China carried out the Lu Xun Medal Reading Campaign and the Red Flag Reading Campaign one after another,aiming to guide young people to read good books and cultivate a positi... At the end of the 1950s,Shanghai region of China carried out the Lu Xun Medal Reading Campaign and the Red Flag Reading Campaign one after another,aiming to guide young people to read good books and cultivate a positive interest in life through reading,which is a gentle and constant form of ideological education.Based on the historical materials collected by Shanghai Archives,the author investigated the background,development,main links,and effects of the reading movement.The research shows that the reading movement has promoted young peoples political awareness,broadened their knowledge horizons,and promoted the formation of a good social atmosphere. 展开更多
关键词 Lu Xun Medal reading Campaign Red Flag reading Campaign YOUTH ideological education
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Load-bearing characteristics and energy evolution of fractured rock masses after granite and sandstone grouting
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作者 WU Xu-kun ZHAO Guang-ming +4 位作者 MENG Xiang-rui LIU Chong-yan LIU Zhi-xi HUANG Shun-jie ZHANG Qi-hang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2810-2825,共16页
Experiments on grouting-reinforced rock mass specimens with different particle sizes and features were carried out in this study to examine the effects of grouting reinforcement on the load-bearing characteristics of ... Experiments on grouting-reinforced rock mass specimens with different particle sizes and features were carried out in this study to examine the effects of grouting reinforcement on the load-bearing characteristics of fractured rock mass.The strength and deformation features of grouting-reinforced rock mass were analyzed under different loading manners;the energy evolution mechanism of grouting-reinforced rock mass specimens with different particle sizes and features was investigated;the energy dissipation ratio and post-peak stress decreasing rate were employed to evaluate the bearing stability of grouting-reinforced rock mass.The results show that the strength and ductility of granite-reinforced rock mass(GRM)under biaxial loading are higher than that of sandstone-reinforced rock mass(SRM)under uniaxial loading.Besides,the energy evolution characteristics of grouting-reinforced rock mass under uniaxial and biaxial loading mainly could be divided into early,middle,and late stages.In the early stage,total,elastic,and dissipation energies were quite small with flatter curves;in the middle stage,elastic energy increased rapidly,whereas dissipation energy increased slowly;in the late stage,dissipation energy increased sharply.The energy dissipation ratio was used to represent the pre-peak plastic deformation.Under uniaxial loading,this ratio increased as the particle size increased and the pre-peak plastic deformation of grouting-reinforced rock mass became larger;under biaxial loading,it dropped as the particle size increased,and the pre-peak plastic deformation of grouting-reinforced rock mass became smaller.The post-peak stress decline rate A_(v) was used to assess the post-peak bearing performance of grouting-reinforced rock mass.Under uniaxial loading,parameter A_(v) exhibited reduction as the particle size kept increasing,and the ability of post-peak of grouting-reinforced rock mass to allow deformation development was greater,and the bearing capacity was greater;under biaxial loading,A_(v) increased with the particle size,and the ability of post-peak of grouting-reinforced rock mass to allow deformation development was low and the bearing capacity was reduced.The findings are considered instrumental in improving the stability of the roadway-surrounding rock by granite and sandstone grouting. 展开更多
关键词 grouting-reinforced rock mass particle size energy dissipation ratio post-peak stress decreasing rate load-bearing characteristics
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Unified Description of the Three Stable Particles in Self-Action Allows Determination of Their Relative Masses
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作者 Yair Goldin Halfon 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期185-196,共12页
The Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-eA<sub>μ</sub>)Ψ=mc<sup>2</sup>Ψ describes the bound states of the electron under the action of external potentials... The Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-eA<sub>μ</sub>)Ψ=mc<sup>2</sup>Ψ describes the bound states of the electron under the action of external potentials, A<sub>μ</sub>. We assumed that the fundamental form of the Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-S<sub>μ</sub>)Ψ=0 should describe the stable particles (the electron, the proton and the dark-matter-particle (dmp)) bound to themselves under the action of their own potentials S<sub>μ</sub>. The new equation reveals that self energy is consequence of self action, it also reveals that the spin angular momentum is consequence of the dynamic structure of the stable particles. The quantitative results are the determination of their relative masses as well as the determination of the electromagnetic coupling constant. 展开更多
关键词 Electron in Self Action Electron-Dark-Matter Particle mass Ratio Analytic Description Dark-Matter-Particle
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Approach to cardiac masses: Thinking inside and outside the box
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作者 Elia De Maria 《World Journal of Clinical Cases》 SCIE 2024年第28期6132-6136,共5页
In this editorial we comment on the article by Huffaker et al,published in the current issue of the World Journal of Clinical Cases.Cardiac masses encompass a broad range of lesions,potentially involving any cardiac s... In this editorial we comment on the article by Huffaker et al,published in the current issue of the World Journal of Clinical Cases.Cardiac masses encompass a broad range of lesions,potentially involving any cardiac structure,and they can be either neoplastic or non-neoplastic.Primitive cardiac tumors are rare,while metastases and pseudotumors are relatively common.Cardiac masses frequently pose significant diagnostic and therapeutic challenges.Multimodality imaging is fundamental for differential diagnosis,treatment,and surgical planning.In particular cardiac magnetic resonance(CMR)is currently the gold standard for noninvasive tissue characterization.CMR allows evaluation of the relationship between the tumor and adjacent structures,detection of the degree of infiltration or expansion of the mass,and prediction of the possible malignancy of a mass with a high accuracy.Different flow charts of diagnostic work-up have been proposed,based on clinical,laboratory and imaging findings,with the aim of helping physicians approach the problem in a pragmatic way(“thinking inside the box”).However,the clinical complexity of cancer patients,in particular those with rare syndromes,requires a multidisciplinary approach and an open mind to go beyond flow charts and diagnostic algorithms,in other words the ability to“think outside the box”. 展开更多
关键词 Cardiac masses Cardiac tumors Cardio-oncology Cardiac magnetic resonance Primitive cardiac tumors
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Exploring the Reasons for Changes in National Reading Behaviour from the Perspective of Media Environmentalism
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作者 JIN Yong-cheng ZHANG Ke-xin 《Journal of Literature and Art Studies》 2024年第6期443-449,共7页
In this paper, through the perspective of Merowitz’s media environmentalism, following the research path of media-scene-behaviour, and based on the results of the national reading survey released by the China Press a... In this paper, through the perspective of Merowitz’s media environmentalism, following the research path of media-scene-behaviour, and based on the results of the national reading survey released by the China Press and Publication Research Institute in the past ten years (2013-2022), we analyse the characteristics of national reading behaviours, explore the reasons for the changes in national reading behaviour in terms of technology, media, and scenarios. It also discusses the future trend of national reading behaviour and the promotion of national reading activities, and puts forward certain countermeasures from the government, schools and the society to make joint efforts to promote national reading. 展开更多
关键词 media convergence media environmentalism national reading behaviour
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Differential diagnosis of gastric submucosal masses and external pressure lesions
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作者 Ying Na Xiang-Dong Liu Hui-Min Xu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第10期3374-3376,共3页
Lesions of the left triangular ligament of the liver are rare,and there are even fewer cases of vascular tumors misdiagnosed as gastrointestinal stromal tumors.We comment on the two cases reported in the article.The a... Lesions of the left triangular ligament of the liver are rare,and there are even fewer cases of vascular tumors misdiagnosed as gastrointestinal stromal tumors.We comment on the two cases reported in the article.The article did not include pictures of laparoscopic surgery,making it unconvincing.For gastric submucosal lesions,enhanced computed tomography venous phase imaging may be beneficial for differential diagnosis.Although endoscopic ultrasound is an effective tool for diagnosing submucosal lesions of the stomach,due to various factors,it cannot achieve an accurate diagnosis.During endoscopic examination,a more accurate diagnosis can be made depending on the personal experience of the operators. 展开更多
关键词 Differential diagnosis Gastric submucosal masses External pressure lesions Endoscopic ultrasonography Computed tomography
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Supervised Learning Method: Critical Analysis and Updating of Cubing Rate Formulas for Determining Bark Masses of Prunus africana (Hook. f.) Kalkman (Rosaceae) in Cameroon
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作者 Armand Ndedy Bile Alain Mpouam +10 位作者 Benoit Fouadjio Lorette Guedeu Kambale Muhesi Steve Tassiamba Paulette Kouam Eric Wete Marius Ela Michèle Yimga Joseph Ambara Louis Aimé Fono Jean Lagarde Betti 《Open Journal of Forestry》 2024年第3期346-368,共23页
The stem barks of Prunus africana are used in the treatment of the benign prostate. Cameroon is one of the important exporters of the barks. Despite the important measures adopted in Cameroon for sustaining its harves... The stem barks of Prunus africana are used in the treatment of the benign prostate. Cameroon is one of the important exporters of the barks. Despite the important measures adopted in Cameroon for sustaining its harvesting, some many chalenges still remain. The objective of this work is to refine the forest management parameters in relation to P. africana in the regions of Adamaoua and the South-West by developing a volume rate which makes it possible to estimate the production for a new stem. The work took place in two phases: in the South-West in 2010 and in Adamaoua in 2011. Data collection used the semi-direct method, while the cubing equation was deduced by the multiple linear regression method. Two models for volume estimation and three models for mass prediction were developed. The predictive parameters retained are diameter, height of the bole and thickness of the bark. Results show that the average mass of the dry bark for a given P. africana tree species is 27.55 ± 14.44 kg and this varies according to the site. The strong adjusted coefficient of determination (adjusted R2) observed illustrates the reliability of the proposed models. These models provide a reliable tool that can be adopted as a standard in Cameroon for P. africana. 展开更多
关键词 Prunus africana Prostate QUOTA mass Model Sustainable Management
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Study on the Interactivity of Controlled and Automatic Information Processing in L2 Reading
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作者 DONG Tiantian WANG Yong 《Sino-US English Teaching》 2024年第7期314-321,共8页
L2 reading is not only an important channel for people to obtain information and knowledge,but also the main way for people to learn a foreign language.Reading information processing can be divided into controlled pro... L2 reading is not only an important channel for people to obtain information and knowledge,but also the main way for people to learn a foreign language.Reading information processing can be divided into controlled processing and automatic processing.Controlled information processing is a conscious and resource-intensive processing model,while automatic information processing is an unconscious and automatic processing model.This study investigates the characteristics and interactivity of controlled and automatic information processing in L2 reading,and explores the roles of controlled and automatic information processing strategies in improving L2 reading ability.The findings are as follows:(a)controlled and automatic information processing is interactive in L2 reading;and(b)the uses of controlled and automatic information processing strategies are beneficial to the improvement of the reading ability of L2 learners.This study has important theoretical and practical value in improving the efficiency of L2 reading teaching and learning. 展开更多
关键词 L2 reading controlled information processing automatic information processing interactivity
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Bearing Capacity Analysis of Spread Footing on Massif in the “Corniche Ouest” of the Dakar Peninsula (Senegal, West Africa)
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作者 Moussa Sawadogo Déthie Sarr Oustasse A. Sall 《Open Journal of Civil Engineering》 2024年第3期421-434,共14页
This study presents various approaches to calculating the bearing capacity of spread footings applied to the rock mass of the western corniche at the tip of the Dakar peninsula. The bearing capacity was estimated usin... This study presents various approaches to calculating the bearing capacity of spread footings applied to the rock mass of the western corniche at the tip of the Dakar peninsula. The bearing capacity was estimated using empirical, analytical and numerical approaches based on the parameters of the rock mass and the foundation. Laboratory tests were carried out on basanite, as well as on the other facies detected. The results of these studies give a range of allowable bearing capacity values varying between 1.92 and 11.39 MPa for the empirical methods and from 7.13 to 25.50 MPa for the analytical methods. A wide dispersion of results was observed according to the different approaches. This dispersion of results is explained by the use of different rock parameters depending on the method used. The allowable bearing capacity results obtained with varying approaches of calculation remain admissible to support the loads. On the other hand, the foundation calculations show acceptable settlement of the order of a millimeter for all the layers, especially in the thin clay layers resting on the bedrock at shallow depths, where the rigidity of the rock reduces settlement. 展开更多
关键词 Peninsula of Dakar Bearing Capacity Basanites Rock mass Spread Footings
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Analysis of the Role of Syntactic Complexity in Students’ Reading Comprehension: A Teacher’s Perspective
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作者 Ma.Leticia Jose C.Basilan Daniel Reds G.De Sagun 《Journal of Contemporary Educational Research》 2024年第8期253-264,共12页
This study examines the role of the syntactic complexity of the text in the reading comprehension skills of students.Utilizing the qualitative method of research,this paper used structured interview questions as the m... This study examines the role of the syntactic complexity of the text in the reading comprehension skills of students.Utilizing the qualitative method of research,this paper used structured interview questions as the main data-gathering instruments.English language teachers from Coral na Munti National High School were selected as the respondents of the study.Finding of the study suggests that the syntactic complexity of the text affects the reading comprehension of the students.Students found it challenging to understand the message that the author conveyed if he or she used a large number of phrases and clauses in one sentence.Furthermore,the complex sentence syntactic structure was deemed the most challenging for students to understand.To overcome said challenges in comprehending text,various reading intervention programs were utilized by teachers.These interventions include focused or targeted instruction and the implementation of the Project Dear,suggested by the Department of Education.These programs were proven to help students improve their comprehension as well as their knowledge in syntactical structure of sentences.This study underscores the importance of selecting appropriate reading materials and implementing suitable reading intervention programs to enhance students’comprehension skills. 展开更多
关键词 reading comprehension Syntactic complexity reading intervention program Syntactic structure
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Deformation characteristics and damage ontologies of soft and hard composite rock masses under impact loading
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作者 LI Jinhua ZHANG Tianyu +3 位作者 WU Baolin SU Peili YANG Yang WANG Pan 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1715-1727,共13页
As one of the most common occurring geological landforms in deep rock formations, the dynamic mechanical properties of layered composite rock bodies under impact loading have been widely studied by scholars. To study ... As one of the most common occurring geological landforms in deep rock formations, the dynamic mechanical properties of layered composite rock bodies under impact loading have been widely studied by scholars. To study the dynamic properties of soft and hard composite rocks with different thickness ratios, this paper utilizes cement, quartz sand and gypsum powder to construct soft and hard composite rock specimens and utilizes a combination of indoor tests, numerical calculations, and theoretical analyses to investigate the mechanical properties of soft and hard composite rock bodies. The test results reveal that:(1) When the proportion of hard rock increases from 20% to 50%, the strength of the combined rock body increases by 69.14 MPa and 87 MPa when the hard rock face and soft rock face are loaded, respectively;however, when the proportion of hard rock is the same, the compressive strength of the hard rock face impact is 9%-17% greater than that of the soft rock face impact;(2) When a specimen of soft and hard combined rock body is subjected to impact loading, the damage mode involves mixed tension and shear damage, and the cracks generally first appear at the ends of the specimen, then develop on the laminar surface from the impact surface, and finally end in the overall damage of the soft rock part. The development rate and the total number of cracks in the same specimen when the hard rock face is impacted are significantly greater than those when the soft rock face is impacted;(3) By introducing Weibull’s statistical strength theory to establish the damage variables of soft-hard combined rock bodies, combined with the DP strength criterion, the damage model and the Kelvin body are concatenated to obtain a statistical damage constitutive model, which can better fit the full stress-strain curve of soft-hard combined rock body specimens under a single impact load. 展开更多
关键词 Soft and hard composite rock mass Dynamic properties Split Hopkinson pressure bar(SHPB) Numerical simulation Intrinsic damage model
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