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Relationship between the Three Laws of Dialectics of Nature and Agricultural Development
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作者 Qianru ZHU 《Asian Agricultural Research》 2023年第7期20-21,共2页
Based on the three laws of dialectics of nature-the law of unity of opposites, the law of mutual change of quality and the law of negation of negation, this paper analyzes the relationship between the three laws and a... Based on the three laws of dialectics of nature-the law of unity of opposites, the law of mutual change of quality and the law of negation of negation, this paper analyzes the relationship between the three laws and agricultural development, and proposes making good use of the three laws to promote the better development of agriculture and realize agricultural modernization. 展开更多
关键词 dialectics of nature Law of unity of opposites Law of mutual change of quality Law of negation of negation Agricultural development
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The Alienation of Nature in Emily Dickinson’s Poems through the Prism of Taoism
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作者 LI Dong-qing 《Journal of Literature and Art Studies》 2024年第3期186-193,共8页
In the poems created by the renowned American poet Emily Dickinson,those related to nature constitute a considerable proportion.However,Dickinson’s attitude toward nature is,in fact,contradictory.On the one hand,Dick... In the poems created by the renowned American poet Emily Dickinson,those related to nature constitute a considerable proportion.However,Dickinson’s attitude toward nature is,in fact,contradictory.On the one hand,Dickinson perceives nature as gentle and kind,akin to a mother.Nature is regarded as“heaven”and embodies harmony.On the other hand,nature possesses its own operational principles and harbors inherent cruelty.According to Dickinson,humans should refrain from excessive interference in the natural order.This article attempts to analyze the similarities in attitude towards nature between Dickinson’s poetry and Taoist philosophy. 展开更多
关键词 Emily Dickinson ALIENATION nature TAOISM
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Problems and Development Suggestions of Nature Education in Jiangxi Province
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作者 Hua LI Shinan XIANG Feiping CHEN 《Meteorological and Environmental Research》 2024年第1期46-47,56,共3页
The forest coverage rate of Jiangxi Province ranks second in China.It has rich natural resources,a long history of ancient color culture and rich red culture.In the development of nature education,Jiangxi Province has... The forest coverage rate of Jiangxi Province ranks second in China.It has rich natural resources,a long history of ancient color culture and rich red culture.In the development of nature education,Jiangxi Province has great potential and advantages.This paper introduces the development conditions of nature education in Jiangxi Province,summarizes the problems existing in the development of nature education in Jiangxi Province from the aspects of the types of nature education and the construction of nature education base,such as simple content and single form,imperfect infrastructure and lack of professionals,and puts forward some suggestions on the development of nature education in Jiangxi Province. 展开更多
关键词 Jiangxi Province nature education PROBLEM Development suggestion
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Dialectics of nature: Temporal and spatial regulation in material sciences 被引量:1
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作者 Jianlong Xia Lei Jiang 《Nano Research》 SCIE EI CAS CSCD 2017年第4期1115-1124,共10页
The cooperative interaction distance measure has been proposed as a novel law pertaining to dialectics of nature, and has been extensively carried out in the design of functional nanomaterials. However, the temporal a... The cooperative interaction distance measure has been proposed as a novel law pertaining to dialectics of nature, and has been extensively carried out in the design of functional nanomaterials. However, the temporal and spatial dimensions are akin to yin and yang, and thus temporal regulation needs to be accounted for when implementing the above-mentioned principle. Here, we summarize recent advances in temporally and spatially regulated materials and devices. We showcase the temporal regulation of organic semiconductors for organic photovoltaics (OPVs) using the example of exciton lifetime manipulation. As an example of spatial regulation, we consider the distribution of charge carriers in core-shell quantum dot (QD) nanocrystals for modulating their optical properties. Long exciton lifetime can in principle increase the exciton diffussion length, which is desiable for high-efficiency large-area OPV devices. Spatially regulated QDs are highly valuable emitters for light-emitting applications. We aim to show that cooperative spatio-temporal regulation of nanomaterils is of vital importance to the development of functional devices. 展开更多
关键词 dialectics of nature temporal regulation spatial regulation singlet fission
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Mushroomβ-glucan and polyphenol formulations as natural immunity boosters and balancers:nature of the application 被引量:1
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作者 Maja Kozarski Anita Klaus +4 位作者 Leo van Griensven Dragica Jakovljevic Nina Todorovic Wan Abd Al Qadr Imad Wan-Mohtar Jovana Vunduk 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期378-396,共19页
Mushrooms are experiencing a kind of renaissance as a part of the contemporary human diet.These valuable organisms are more than food,they fit in perfectly as a novel market group known as nutra-mycoceuticals.Immune-b... Mushrooms are experiencing a kind of renaissance as a part of the contemporary human diet.These valuable organisms are more than food,they fit in perfectly as a novel market group known as nutra-mycoceuticals.Immune-balancing mushroom dietary fibers and secondary metabolites such as polyphenols are the main focus of the healthcare industry.Wellness and cosmetic companies are increasingly using mushroom extracts rich in these ingredients.This review considers the basic molecular immunomodulatory mechanisms of action of the most commonly used mushroom dietary fibers,β-glucans.The literature data on their bioavailability,metabolic transformations,preclinical and human clinical research,and safety are discussed.Immunomodulatory mechanisms of polyphenol ingredients are also considered.These molecules present great potential in the design of the new immunity balancer formulations according to their widespread structural diversity.Finally,we draw attention to the perspectives of modern trends in mushroom nutraceutical and cosmeceutical formulations to strengthen and balance immunity. 展开更多
关键词 MUSHROOMS Β-GLUCAN POLYPHENOLS Immunity boosters Superfood Natural cosmetics
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The Man Who Organized Nature: The Life of Linnaeus by Gunnar Broberg
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作者 John Richard Schrock 《Entomotaxonomia》 CSCD 2023年第3期239-240,共2页
GunnarBroberg(1942–2022),a professor of history ideas and sciences at the Lund University in Sweden,has assembled and summarized virtually all of the contemporary documents relating to the life of Carl Linnaeus(1707... GunnarBroberg(1942–2022),a professor of history ideas and sciences at the Lund University in Sweden,has assembled and summarized virtually all of the contemporary documents relating to the life of Carl Linnaeus(1707–1778).This is therefore a fact-laden and definitive personal biography of the founder of our systems of plant and animal taxonomy.Linnaeus’childhood included much time in nature that forever provided him an experience background for the huge amount of plant and animal species he would encounter.In his early days,his country was in an era of poverty where“hordes of starving,homeless people drifted along the roads in the years when the harvest failed.”Linnaeus himself“...could lie awake all night as he lacked the money for evening meals when he was a student.”He inserted paper into his shoes to cover the holes on which he walked. 展开更多
关键词 MONEY himself nature
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On Reserves of Hippophae rhamnoides L. Fruit on the Territory of the Zarafshan National Nature Park of Uzbekistan
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作者 Sherzod B. Erdonov Azizbek V. Maxmudov +3 位作者 Ozodbek S. Abduraimov Akmal L. Allamurotov Bekzod J. Mavlanov Odilbek T. Mamatkasimov 《American Journal of Plant Sciences》 2023年第8期946-954,共8页
The article is devoted to the study of stocks of Hippophae rhamnoides fruits on the territory of the Zarafshan National Park. Hippophae rhamnoides is a medicinal plant. This species is a naturally distributed plant. A... The article is devoted to the study of stocks of Hippophae rhamnoides fruits on the territory of the Zarafshan National Park. Hippophae rhamnoides is a medicinal plant. This species is a naturally distributed plant. All parts of Hippophae rhamnoides are a source of biologically active substances, especially flavonoids, carotenoids, phytosterols and others. In the course of field studies, 10 monitoring sites were selected in the size of 10 × 10 m, and the productivity of one site in the amount of 10 × 10 averaged 51.33 ± 8.24 kg. According to the results obtained, it was revealed that the biological reserve averages 21.9 tons, respectively, the operational reserve is 13.14 tons and the volume of annual harvesting averages 1.31 tons. When the water level of the Zarafshan River rises, some plants are damaged. 展开更多
关键词 Hippophae rhamnoides Zarafshan National Natural Park Fruit Stock Monitoring Plots
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The Significance of Constructing TCM Psychosomatic Medicine from the Holistic View of the Unity of Nature and Man
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作者 Wutong Song Hongxin Cao 《Chinese Medicine》 2023年第4期267-275,共9页
With the development of medical technology, the problem of fragmentation of medical research has become increasingly prominent, and a series of iatrogenic diseases, drug-induced diseases and drug toxicity and side eff... With the development of medical technology, the problem of fragmentation of medical research has become increasingly prominent, and a series of iatrogenic diseases, drug-induced diseases and drug toxicity and side effects have resulted in an increase in the number of diseases. In the face of these problems, the medical concept has been re-examined and re-thought. The concept of the holistic view of the unity of nature and man in traditional Chinese medicine has certain enlightenment for dealing with the problems in the current medical development. Based on the holistic view of the unity of nature and man, the overall connection between human’s heart and body and nature is explained, and the further construction of TCM psychosomatic medicine is conducive to guiding the diagnosis and treatment of clinical diseases, and providing new enlightenment for the current medical concept thinking and clinical disease research. 展开更多
关键词 Traditional Chinese Medicine The Unity of nature and Man Holistic View TCM Psychosomatic Medicine
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Exploration of Nature Education Path for Teenagers:A Case Study of Yancheng Wetland Nature Education Based on the World Natural Heritage Site
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作者 Wenhui LI Xiejuan TANG +1 位作者 Hongyang LI Xingxing SUN 《Asian Agricultural Research》 2023年第10期40-44,共5页
Nature education is the trend of the current social development.By gradually improving the awareness of ecological civilization among the whole people,the achievements in ecological civilization are jointly built and ... Nature education is the trend of the current social development.By gradually improving the awareness of ecological civilization among the whole people,the achievements in ecological civilization are jointly built and shared by the whole people.Yancheng Yellow Sea Wetland is a characteristic natural resource and the name card of Yancheng City,and also an important part of the natural education of teenagers in Yancheng.As one of the main resources of nature education in Yancheng,the Yellow Sea Wetland World Natural Heritage resources play a more important role in the cultivation of youth ecological civilization values and legal awareness of environmental protection.Based on the protection and utilization of the Yellow Sea Wetland World Natural Heritage resources,this paper explores the methods and approaches of nature education for teenagers in Yancheng. 展开更多
关键词 nature education Yellow sea wetland World natural heritage
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Development and validation of an online calculator to predict the pathological nature of colorectal tumors
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作者 Ya-Dan Wang Jing Wu +9 位作者 Bo-Yang Huang Chun-Mei Guo Cang-Hai Wang Hui Su Hong Liu Miao-Miao Wang Jing Wang Li Li Peng-Peng Ding Ming-Ming Meng 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第7期1271-1282,共12页
BACKGROUND No single endoscopic feature can reliably predict the pathological nature of colorectal tumors(CRTs).AIM To establish and validate a simple online calculator to predict the pathological nature of CRTs based... BACKGROUND No single endoscopic feature can reliably predict the pathological nature of colorectal tumors(CRTs).AIM To establish and validate a simple online calculator to predict the pathological nature of CRTs based on white-light endoscopy.METHODS This was a single-center study.During the identification stage,530 consecutive patients with CRTs were enrolled from January 2015 to December 2021 as the derivation group.Logistic regression analysis was performed.A novel online calculator to predict the pathological nature of CRTs based on white-light images was established and verified internally.During the validation stage,two series of 110 images obtained using white-light endoscopy were distributed to 10 endoscopists[five highly experienced endoscopists and five less experienced endoscopists(LEEs)]for external validation before and after systematic training.RESULTS A total of 750 patients were included,with an average age of 63.6±10.4 years.Early colorectal cancer(ECRC)was detected in 351(46.8%)patients.Tumor size,left semicolon site,rectal site,acanthosis,depression and an uneven surface were independent risk factors for ECRC.The C-index of the ECRC calculator prediction model was 0.906(P=0.225,Hosmer-Lemeshow test).For the LEEs,significant improvement was made in the sensitivity,specificity and accuracy(57.6%vs 75.5%;72.3%vs 82.4%;64.2%vs 80.2%;P<0.05),respectively,after training with the ECRC online calculator prediction model.CONCLUSION A novel online calculator including tumor size,location,acanthosis,depression,and uneven surface can accurately predict the pathological nature of ECRC. 展开更多
关键词 Pathological nature Colorectal tumors White-light endoscopy Online calculator Early colorectal cancer
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Treatment on Nature’s lap:Use of herbal products in the management of hyperglycemia
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作者 Somdatta Giri Jayaprakash Sahoo +2 位作者 Ayan Roy Sadishkumar Kamalanathan Dukhabandhu Naik 《World Journal of Diabetes》 SCIE 2023年第4期412-423,共12页
Diabetes mellitus(DM)is characterized by persistently elevated blood glucose concentration that lead to multisystem complications.There are about 400 medicinal plants cited to have a beneficial effect on DM.We must ch... Diabetes mellitus(DM)is characterized by persistently elevated blood glucose concentration that lead to multisystem complications.There are about 400 medicinal plants cited to have a beneficial effect on DM.We must choose products wisely based on data derived from scientific studies.However,a major obstacle in the amalgamation of herbal medicine in modern medical practices is the lack of clinical data on its safety,efficacy and drug interaction.Trials of these herbal products often underreport the side effects and other crucial intervention steps deviating from the standards set by Consolidated Standards of Reporting Trials.Due to a lack of knowledge of the active compounds present in most herbal medicines,product standardization is difficult.Cost-effectiveness is another issue that needs to be kept in mind.In this mini-review,we focus on the antihyperglycemic effect of herbal products that are commonly used,along with the concerns stated above. 展开更多
关键词 Herbal product HBA1C Diabetes mellitus Active compound Natural therapy COST-EFFECTIVENESS
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Conception and Planning of Campus Landscape Combined with Nature Education Based on Species Survey:A Case Study of North China University of Technology
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作者 LI Tongyu WANG Xiaobo 《Journal of Landscape Research》 2023年第2期6-10,共5页
From the perspective of habitats and species diversity in biodiversity,the species and richness of plants and animals in the campus green spaces of North China University of Technology were surveyed comprehensively by... From the perspective of habitats and species diversity in biodiversity,the species and richness of plants and animals in the campus green spaces of North China University of Technology were surveyed comprehensively by natural observation and field investigation.A total of 118 species of plants and 70species of animals were investigated.The relationship between plants and animals on the campus was analyzed qualitatively.Based on this,the richness of species in the plots suitable for natural education in the sites was investigated and analyzed,and the situations in different seasons were compared to plan natural education areas and trails.In addition,the ways to increase the biodiversity of the sites,the connection between habitats and landscape elements,and the setting of relevant landscape sites were discussed,and it was proposed to integrate more natural education methods to attract people to carry out natural education of biodiversity in the university campus with a learning atmosphere. 展开更多
关键词 University campus BIODIVERSITY Natural education Landscape design
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Determination of Main Design Indicators of Patrol Road in Nature Reserves
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作者 Hongbo LIU Shuangbei ZENG 《Asian Agricultural Research》 2023年第8期49-51,共3页
In principle,nature reserves are managed and controlled according to the core area and the general control area.At present,there is no relevant design specification for the design system of patrol road in various prot... In principle,nature reserves are managed and controlled according to the core area and the general control area.At present,there is no relevant design specification for the design system of patrol road in various protected areas.This paper analyzed the factors to be considered in determining the grade,horizontal and vertical design indicators,and cross section indicators of the patrol road in the protected area,and came up with the corresponding design indicators and parameters,so as to provide a certain reference for the subsequent patrol road design. 展开更多
关键词 nature reserves Patrol road Design indicators Road design
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How to Inscribe Nature and the Environment Into the Philosophy of Politics?
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作者 Maria Wodzińska 《Journal of Philosophy Study》 2023年第3期125-130,共6页
The purpose of this text is to examine,describe,and elaborate on contemporary attempts to incorporate nature and the environment into reflection related to the philosophy of politics.Both attempts to extend Foucault’... The purpose of this text is to examine,describe,and elaborate on contemporary attempts to incorporate nature and the environment into reflection related to the philosophy of politics.Both attempts to extend Foucault’s biopolitics and attempts to introduce competing concepts are analysed.This theme has a strong presence mainly due to the multifaceted degradation of nature and the environment,contamination,and over-extraction of natural resources in the era of climate and ecological crises.In this text,the author analyses interdisciplinary activities developed by researchers associated with very different fields,such as anthropology and art criticism,which are based on the philosophy of politics. 展开更多
关键词 BIOPOLITICS necropolitics geontopower geontopolitics nature and environment extractivism
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How topography and neighbor shape the fate of trees in subtropical forest restoration:Environmental filtering and resource competition drive natural regeneration
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作者 Haonan Zhang Xingshuo Zhang +7 位作者 Yingying Lv Yanyan Ni Baokun Xu Xiangnan Han Xiao Cao Qingpei Yang Wanggu Xu Zhedong Qian 《Forest Ecosystems》 SCIE CSCD 2024年第1期73-86,共14页
The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the community.However,although environmental filtering d... The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the community.However,although environmental filtering due to microtopographic heterogeneity and resource competition among plants caused by spatial variation in tree density and size are considered to be very important in explaining the mechanisms of community assembly,their effects on the processes of individual mortality and recruitment in natural forest regeneration,as well as their relative contributions,are still poorly understood.To address this,we established a 12-ha permanent plot in a subtropical evergreen broad-leaved forest area and measured microtopographic variables such as elevation,slope,aspect,and terrain position index(TPI)using a total station.We monitored the individual mortality and recruitment in forest natural regeneration through repeated surveys at 5-year intervals.We fitted spatial covariance models to jointly use multiple factors from three groups of variables(microtopographic effect,neighborhood density effects,neighborhood size effects)as explanatory variables to analyze their roles in driving the mortality and recruitment of all individual and 12 dominant species in forest natural regeneration at the neighborhood scale.Our results show that:(1)In the crucial early stages of secondary forest restoration,natural regeneration is influenced by a synergy of environmental filtering,due to microtopographic heterogeneity,and resource competition among plants.(2)For distinct species responses,evergreen dominant species'mortality is largely explained by neighborhood effects,while deciduous species are more affected by topographic factors.Furthermore,the adverse effects of larger conspecific trees on younger trees indicate a pattern of competitive pressure leading to mortality among regenerating trees,such pattern emphasis the influence of parent trees on natural regeneration.(3)As trees grow,their interaction with these stressors evolves,suggesting a shift in their resource acquisition strategies and response to neighborhood effects and environmental factors.Despite these changes,the relative importance of topographic factors in determining survival and recruitment success remains constant.This research highlights the importance of considering both environmental and neighborhood effects in forest management,particularly in early secondary forest restoration. 展开更多
关键词 Natural regeneration MICROTOPOGRAPHY Neighborhood effects Mortality and recruitment
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New insights into the deposition of natural gas hydrate on pipeline surfaces:A molecular dynamics simulation study
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作者 Jun Zhang Hai-Qiang Fu +7 位作者 Mu-Zhi Guo Zhao Wang Li-Wen Li Qi Yin You-Guo Yan Wei Wei Wei-Feng Han Jie Zhong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期694-704,共11页
Natural gas hydrate(NGH)can cause pipeline blockages during the transportation of oil and gas under high pressures and low temperatures.Reducing hydrate adhesion on pipelines is viewed as an efficient way to prevent N... Natural gas hydrate(NGH)can cause pipeline blockages during the transportation of oil and gas under high pressures and low temperatures.Reducing hydrate adhesion on pipelines is viewed as an efficient way to prevent NGH blockages.Previous studies suggested the water film can greatly increase hydrate adhesion in gas-dominant system.Herein,by performing the molecular dynamics simulations,we find in water-dominant system,the water film plays different roles in hydrate deposition on Fe and its corrosion surfaces.Specifically,due to the strong affinity of water on Fe surface,the deposited hydrate cannot convert the adsorbed water into hydrate,thus,a water film exists.As water affinities decrease(Fe>Fe_(2)O_(3)>FeO>Fe_(3)O_(4)),adsorbed water would convert to amorphous hydrate on Fe_(2)O_(3)and form the ordered hydrate on FeO and Fe_(3)O_(4)after hydrate deposition.While absorbed water film converts to amorphous or to hydrate,the adhesion strength of hydrate continuously increases(Fe<Fe_(2)O_(3)<FeO<Fe_(3)O_(4)).This is because the detachment of deposited hydrate prefers to occur at soft region of liquid layer,the process of which becomes harder as liquid layer vanishes.As a result,contrary to gas-dominant system,the water film plays the weakening roles on hydrate adhesion in water-dominant system.Overall,our results can help to better understand the hydrate deposition mechanisms on Fe and its corrosion surfaces and suggest hydrate deposition can be adjusted by changing water affinities on pipeline surfaces. 展开更多
关键词 DEPOSITION Natural gas hydrate Pipelines Water affinity Adhesion strength
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Effect of artificial natural light on the development of myopia among primary school-age children in China:a three-year longitudinal study
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作者 Hui-Min Cai Meng-Yan Li +6 位作者 Yi Cao Yu-Lin Wu Ming Liang Yu-Shi Chen Bi-Kun Xian Yu-Juan Huang Xiang-Bin Kong 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期924-931,共8页
AIM:To assess the efficacy of artificial natural light in preventing incident myopia in primary school-age children.METHODS:This is a prospective,randomized control,intervention study.A total of 1840 students from 39 ... AIM:To assess the efficacy of artificial natural light in preventing incident myopia in primary school-age children.METHODS:This is a prospective,randomized control,intervention study.A total of 1840 students from 39 classes in 4 primary schools in Foshan participated in this study.The whole randomization method was adopted to include classes as a group according to 1:1 randomized control.Classrooms in the control group were illuminated by usual light,and classrooms in the intervention group were illuminated by artificial natural light.All students received uncorrected visual acuity and best-corrected visual acuity measurement,non-cycloplegic autorefraction,ocular biometric examination,slit lamp and strabismus examination.Three-year follow-up,the students underwent same procedures.Myopia was defined as spherical equivalent refraction≤-0.50 D and uncorrected visual acuity<20/20.RESULTS:There were 894 students in the control group and 946 students in the intervention group with a mean±SD age of 7.50±0.53y.The three-year cumulative incidence rate of myopia was 26.4%(207 incident cases among 784 eligible participants at baseline)in the control group and 21.2%(164 incident cases among 774 eligible participants at baseline)in the intervention group[difference of 5.2%(95%CI,3.7%to 10.1%);P=0.035].There was also a significant difference in the three-year change in spherical equivalent refraction for the control group(-0.81 D)compared with the intervention group[-0.63 D;difference of 0.18 D(95%CI,0.08 to 0.28 D);P<0.001].Elongation of axial length was significantly different between in the control group(0.77 mm)and the intervention group[0.72 mm;difference of 0.05 mm(95%CI,0.01 to 0.09 mm);P=0.003].CONCLUSION:Artificial natural light in the classroom of primary schools can result in reducing incidence rate of myopia during a period of three years. 展开更多
关键词 MYOPIA artificial natural light school-age children EFFICACY
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Microstructure and mechanical properties stability of pre-hardening treatment in Al-Cu alloys for pre-hardening forming process
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作者 Liping Tang Pengfei Wei +1 位作者 Zhili Hu Qiu Pang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期539-551,共13页
The stability of the microstructure and mechanical properties of the pre-hardened sheets during the pre-hardening forming(PHF)process directly determines the quality of the formed components.The microstructure stabili... The stability of the microstructure and mechanical properties of the pre-hardened sheets during the pre-hardening forming(PHF)process directly determines the quality of the formed components.The microstructure stability of the pre-hardened sheets was in-vestigated by differential scanning calorimetry(DSC),transmission electron microscopy(TEM),and small angle X-ray scattering(SAXS),while the mechanical properties and formability were analyzed through uniaxial tensile tests and formability tests.The results in-dicate that the mechanical properties of the pre-hardened alloys exhibited negligible changes after experiencing 1-month natural aging(NA).The deviations of ultimate tensile strength(UTS),yield strength(YS),and sheet formability(Erichsen value)are all less than 2%.Also,after different NA time(from 48 h to 1 month)is applied to alloys before pre-hardening treatment,the pre-hardened alloys possess stable microstructure and mechanical properties as well.Interestingly,with the extension of NA time before pre-hardening treatment from 48 h to 1 month,the contribution of NA to the pre-hardening treatment is limited.Only a yield strength increment of 20 MPa is achieved,with no loss in elongation.The limited enhancement is mainly attributed to the fact that only a limited number of clusters are transformed into Guinier-Preston(GP)zones at the early stage of pre-hardening treatment,and the formation ofθ''phase inhibits the nucleation and growth of GP zones as the precipitated phase evolves. 展开更多
关键词 Al-Cu alloy pre-hardened alloy natural aging mechanical properties MICROSTRUCTURE
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Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents
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作者 Willian Orlando Castillo-Ordoñez Nohelia Cajas-Salazar Mayra Alejandra Velasco-Reyes 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期846-854,共9页
Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinester... Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinesterase activity,mitochondrial dysfunction,genotoxicity,and neuroinflammation are present in this syndrome,which leads to neurodegeneration.Neurodegenerative pathologies such as Alzheimer’s disease are considered late-onset diseases caused by the complex combination of genetic,epigenetic,and environmental factors.There are two main types of Alzheimer’s disease,known as familial Alzheimer’s disease(onset<65 years)and late-onset or sporadic Alzheimer’s disease(onset≥65 years).Patients with familial Alzheimer’s disease inherit the disease due to rare mutations on the amyloid precursor protein(APP),presenilin 1 and 2(PSEN1 and PSEN2)genes in an autosomaldominantly fashion with closely 100%penetrance.In contrast,a different picture seems to emerge for sporadic Alzheimer’s disease,which exhibits numerous non-Mendelian anomalies suggesting an epigenetic component in its etiology.Importantly,the fundamental pathophysiological mechanisms driving Alzheimer’s disease are interfaced with epigenetic dysregulation.However,the dynamic nature of epigenetics seems to open up new avenues and hope in regenerative neurogenesis to improve brain repair in Alzheimer’s disease or following injury or stroke in humans.In recent years,there has been an increase in interest in using natural products for the treatment of neurodegenerative illnesses such as Alzheimer’s disease.Through epigenetic mechanisms,such as DNA methylation,non-coding RNAs,histone modification,and chromatin conformation regulation,natural compounds appear to exert neuroprotective effects.While we do not purport to cover every in this work,we do attempt to illustrate how various phytochemical compounds regulate the epigenetic effects of a few Alzheimer’s disease-related genes. 展开更多
关键词 Alzheimer’s disease EPIGENETICS genes METHYLATION natural products
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OSDA-free synthesis of FeZSM-22 zeolite from natural minerals for n-octane hydroisomerization
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作者 Tiesen Li Ting Chen +5 位作者 Yinghui Ye Peng Dong TinghaiWang Qingyan Cui Chan Wang Yuanyuan Yue 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期51-59,共9页
A seed-directed approach to synthesizing Fe ZSM-22 zeolite without organic structure directing agent(OSDA)was developed by using Fe-rich diatomite as all aluminum and iron sources.The Fe ZSM-22zeolite with optimal cry... A seed-directed approach to synthesizing Fe ZSM-22 zeolite without organic structure directing agent(OSDA)was developed by using Fe-rich diatomite as all aluminum and iron sources.The Fe ZSM-22zeolite with optimal crystallinity and purity can be obtained by systematically adjusting feed composition and synthesis conditions.Characterizations show that Fe ZSM-22 zeolite synthesized with OSDA-free owns high crystallinity,obvious thin needle-shaped morphology and high Bronsted/Lewis acid ratio.Significantly,when used for n-octane hydroisomerization reaction,its derived catalyst exhibits the best catalytic performance reflected by the highest selectivity to C_(8)isomers compared to the two reference catalysts prepared based on a Fe-containing and a Fe-free ZSM-22 synthesized through an OSDA-directed route from natural diatomite and conventional chemicals,respectively.This work provides an alternative route to sustainably synthesizing heteroatomic zeolites with high performance. 展开更多
关键词 FeZSM-22 zeolite OSDA-free synthesis Natural minerals n-octane hydroisomerization
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