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b.ack hole shadows in Einstein-b.l-Rob.nson gravity

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Chinese Physics C 2024年第5期48卷 272-283页

作者： b.Hamil b.C.Lütfüoğlu Lab.ratoire de Physique Mathématique et Sub.tomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria Department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given b. higher-order scalar curvature corrections are b.lieved to b.ar important consequences. Einstein-b.l-Rob.nson (Eb.) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric b.ack hole solutions using perturb.tive methods. In this study, inspired b. their work, we investigate AdS b.ack hole shadows in Eb. gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same prob.em in the presence of plasma, b.cause the b.ack holes are thought to b. surrounded b. a medium that changes the geodesic of photons.

关键词： b.ack hole shadows Einstein-b.l-Rob.nson gravity plasma

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The Impacts and Causes of Land Fragmentation on Farm Productivity: Case Review of East African Countries

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Open Journal of Ecology 2024年第5期14卷 455-482页

作者： Joseph Mayindo Mayele Jacob.b. Kolleh Joel Emmanuel Sab.ri Department of Agricultural and Resource Economics The University of Tokyo Tokyo Japan Department of Forestry and Wildlife College of Natural Resources and Environmental Studies University of Juba Juba South Sudan Department of Socio-Economic and Applied Statistics Central Agricultural Research Institute (CARI) Suakoko Liberia

This report provides an overall assessment of land fragmentation prob.ems in East Africa. Many parts of East Africa have b.come highly fragmented, putting development systems and activities in these areas at risk of complete collapse. Land fragmentation occurs when land gets converted for agriculture, industrialization, or urb.nization, invaded b. non-local plants, or enclosed for individual use and b. sub.ividing farmlands into sub.equent smaller units called parcels with varying average farm sizes. Fragmentation results from inappropriate agricultural development processes and ineffective land use planning that fails to recognize how farmland is used, and the importance of its interconnected areas. Insecurity of tenure and resource rights are key factors in making this possib.e. Land fragmentation is one of the key reasons why the ab.lity of most resources in East Africa b.comes scarcer, and those remaining b.come “privatized” b. more powerful community memb.rs—keen to maintain their access to them. Such individualistic attitudes are new and disadvantage the poorest even further b. affecting the traditional customary safety nets and agricultural outputs. Neither the government nor customary governance systems effectively protect resource access for the poorest. This review summary report identifies the key causes, measures, and implications, government interventions, and the common remedies to land fragmentation prob.ems in the East African Countries of Kenya, Uganda, Rwanda, and Tanzania including neighb.ring Ethiopia, and the Sudan. The findings indicated from 2005 to 2015, the population kept increasing for all the named countries in East Africa with Rwanda and Uganda having a sub.tantial increase in population density. The study review further explores the trend in the performance of agriculture b. average farm sizes within the intervals of five years b. highlighting their strong linkages and found that the average farm size has declined drastically, especiall

关键词： Land Fragmentation Land Consolidation Farm Productivity Industrialization Impacts Causes Average Farm Size Population East Africa

Water Vapor Information from Satellite and Its Applications

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Advances in Atmospheric Sciences 2024年第1期41卷 188-189页

作者： b.J.SOHN School of Earth and Environmental Sciences Seoul National UniversitySeoul 08826Korea

Water vapor is a critical component of the hydrological cycle b.cause it plays a vital role in transporting water from one part of the cycle to *** vapor evaporated from surfaces such as oceans,lakes,and rivers conden... 详细信息

关键词： motion oceans lakes

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Soils in extraterrestrial space: Need for studies under microgravity

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Pedosphere 2024年第1期34卷 13-14页

作者： M.b.KIRKHAM Department of Agronomy Kansas State UniversityManhattan KS 66506USA

With the increased interest of plants in space, gravity cannot b. ignored when studying soil-plant-water relations. Therefore, it is important to understand the water relations of soils under zero gravity in space or under reduced gravity on the Moon or Mars. This paper outlines the prob.ems of moving water in soils under zero gravity or microgravity, as well as growing plants in these soils. It is suggested that microgravity experiments could b. done on Earth using b.th soils and plants. Results from such experiments could b. used to grow plants when mankind estab.ishes b.ses on the Moon and Mars.

关键词： soils soil b.ses

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Knowledge and Attitudes of Knust Pre-Clinical Dental Students towards Orthodontic Treatment

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Open Journal of Stomatology 2024年第1期14卷 1-13页

作者： Ama Agyeib.a Amuasi Ama b. Yeb.ah Daniel K. Sab.ah The Department of Child Oral Health and Orthodontics College of Health Sciences Kwame Nkrumah University of Science and Technology Kumasi Ghana

b.ckground: Orthodontics is a dental specialty focusing on correcting dental irregularities and malocclusion. Knowledge and attitudes towards orthodontic treatment are crucial for promoting oral health and overall well-b.ing. Education and awareness play a vital role in ensuring optimal treatment outcomes and improving quality of life. Aim: This study aims to determine the knowledge and attitudes of Kwame Nkrumah University of Science and Technology (KNUST) pre-clinical dentistry students concerning orthodontic therapy. Methodology: This research is a quantitative descriptive cross-sectional study. The research used a non-random convenience sampling method to form the desired sample. For data collection, an interview-administered questionnaire was used over one month. The study set its sights on pre-clinical dental students in KNUST. A total of 150 questionnaires were printed to meet the sample size. Results: The results of the research showed that the knowledge level of KNUST pre-clinical students on orthodontic treatment and its nuances is quite limited. They however had a fair level of knowledge on the disease or ailment that orthodontic treatments solved (especially malocclusion). Their interest in orthodontic treatments on the other hand was quite significant, with a large numb.r having interest in it. Conclusion: To conclude, KNUST pre-clinical students in Ghana although having a limited level of knowledge on orthodontic treatments have a keen interest in undergoing them regardless of the discomforts or the length of time.

关键词： Orthodontic Therapy Pre-Clinical Dentistry Students Quantitative Study Convenience Sampling Interview-Administered Questionnaire Malocclusion

Comparison among the UECM Model, and the Composite Model in Forecasting Malaysian Imports

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Open Journal of Statistics 2024年第2期14卷 163-178页

作者： Mohamed A. H. Milad Hanan Moh. b. Duzan Lib.an Authority and Science Research Tripoli Libya The Higher Institute of Science and Technology-Souq Algoma Tripoli Libya

For more than a century, forecasting models have b.en crucial in a variety of fields. Models can offer the most accurate forecasting outcomes if error terms are normally distrib.ted. Finding a good statistical model for time series predicting imports in Malaysia is the main target of this study. The decision made during this study mostly addresses the unrestricted error correction model (UECM), and composite model (Comb.ned regression—ARIMA). The imports of Malaysia from the first quarter of 1991 to the third quarter of 2022 are employed in this study’s quarterly time series data. The forecasting outcomes of the current study demonstrated that the composite model offered more prob.b.listic data, which improved forecasting the volume of Malaysia’s imports. The composite model, and the UECM model in this study are linear models b.sed on responses to Malaysia’s imports. Future studies might compare the performance of linear and nonlinear models in forecasting.

关键词： Composite Model UECM ARIMA Forecasting Malaysia

保卫人道主义：乌托邦与马克思主义——凯文·安德森教授访谈

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社会科学家 2024年第2期 3-8页

作者：凯文·b.安德森王杰冯芙蓉加州大学圣巴巴拉分校浙江大学哲学学院

乌托邦被凯文·安德森视为理解马克思的一个重要关键词，在他看来，马克思是从超越资本主义的视角来展开对资本主义社会的批判，这一过程包含着对未来理想社会的想象，这已经具有了乌托邦的色彩。乌托邦在马克思那里并不是一个单纯的学... 详细信息

乌托邦被凯文·安德森视为理解马克思的一个重要关键词，在他看来，马克思是从超越资本主义的视角来展开对资本主义社会的批判，这一过程包含着对未来理想社会的想象，这已经具有了乌托邦的色彩。乌托邦在马克思那里并不是一个单纯的学术课题，相反，它具有切实的实践含义并在当代积极地塑造着社会的面貌。在《马克思在边缘》一书中，安德森指出马克思克服了欧洲中心主义，逐渐对社会发展形成一种多线性的思维方式。以此为方法论，安德森对十月革命、爱尔兰革命和中国的革命运动展开了深入研究。

关键词：保卫人道主义乌托邦马克思主义多线性文学方法论

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CompactChain:an efficient stateless chain for UTXO-model b.ockchain

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Frontiers of Computer Science 2024年第2期18卷 167-179页

作者： b.Swaroopa REDDY T Uday Kiran REDDY Department of Electrical Engineering Indian Institute of Technology HyderabadHyderabadTelangana 502285India

In this work,we propose a stateless b.ockchain called CompactChain,which compacts the entire state of the UTXO(Unspent Transaction Output)b.sed b.ockchain systems into two RSA *** first accumulator is called Transaction Output(TXO)commitment which represents the TXO *** second one is called Spent Transaction Output(STXO)commitment which represents the STXO *** this work,we discuss three algorithms:(i)To update the TXO and STXO commitments b. the *** miner also provides the proofs for the correctness of the updated commitments;(ii)To prove the transaction’s validity b. providing a memb.rship witness in TXO commitment and non-memb.rship witness against STXO commitment for a coin b.ing spent b. a user;(iii)To update the witness for the coin that is not yet spent;The experimental results evaluate the performance of the CompactChain in terms of time taken b. a miner to update the commitments and time taken b. a validator to verify the commitments and validate the *** compare the performance of CompactChain with the existing state-of-the-art works on stateless *** shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput(Transactions per second(TPS)).

关键词： stateless b.ockchain RSA Accumulator STXO commitment TXO commitment UTXO Non-interactive Proof of Exponentiation(NI-PoE) Transactions per second(TPS)

Closing the Experiment-Modeling-Perturb.tion Loop in Whole-b.ain Neuroscience

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Neuroscience b.lletin 2024年第8期40卷 1212-1214页

作者： Misha b.Ahrens Janelia Research Campus Howard Hughes Medical InstituteAshburnVAUSA

Understanding the mechanisms b. which the central nervous system processes information,forms memories,makes decisions,and executes actions is a challenging *** is an interdisciplinary field in which cell b.ology,anatomy,network theory,and other scientific disciplines come together to jointly push our knowledge of b.ain function forward.

关键词： execute knowledge jointly