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Non-centrosymmetric topological phase probed by non-linear Hall effect

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national Science Review 2024年第6期11卷 180-188页

作者： Naizhou Wang Jing-Yang You Aifeng Wang Xiaoyuan Zhou Zhaowei Zhang Shen Lai Yuan-Ping Feng Hsin Lin Guoqing Chang Wei-bo Gao Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Department of Physics National University of Singapore Low Temperature Physics Laboratory College of Physics and Center for Quantum Materials and Devices Chongqing University centre for Advanced 2D Materials National University of Singapore Institute of Physics Academia Sinica The Photonics Institute and centre for Disruptive Photonic technologies Nanyang Technological University

Non-centrosymmetric topological material has atracted intense atention due to its superior characteristics as compared with the centrosymmetric one, although probing the local quantum geometry in non-centrosymmetric topological material remains challenging. The non-linear Hall（NLH） effect provides an ideal tool to investigate the local quantum geometry. Here, we report a non-centrosymmetric topological phase in ZrTe5, probed by using the NLH effect. The angle-resolved and temperature-dependent NLH measurement reveals the inversion and ab-plane mirror symmetries breaking at etical calculation. Our findings identify a new non-centrosymmetric phase of ZrTe5and provide a platform to probe and control local quantum geometry via crystal symmetries.

关键词： non-linear Hall effect topological insulator ZrTe5

Target acquisition performance in the presence of JPEG image compression

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Defence Technology（防务技术） 2024年第3期33卷 30-41页

作者： Boban Bondzulic Nenad Stojanovic Vladimir Lukin Sergey A.Stankevich Dimitrije Bujakovic Sergii Kryvenko University of Defence in Belgrade Military AcademyVeljka Lukica Kurjaka 3311000 BelgradeSerbia national Aerospace University Department of Information-Communication TechnologiesChkalova 1761070 KharkivUkraine national Academy of sciences of Ukraine Scientific Centre for Aerospace Research of the EarthOles Honchar 55-b01054 KyivUkraine

This paper presents an investigation on the effect of JPEG compression on the similarity between the target image and the background,where the similarity is further used to determine the degree of clutter in the *** new clutter metrics based on image quality assessment are introduced,among which the Haar wavelet-based perceptual similarity index,known as HaarPSI,provides the best target acquisition prediction *** is shown that the similarity between the target and the background at the boundary between visually lossless and visually lossy compression does not change significantly compared to the case when an uncompressed image is *** future work,through subjective tests,it is necessary to check whether this presence of compression at the threshold of just noticeable differences will affect the human target acquisition *** values are compared with the results of subjective tests of the well-known target Search_2 database,where the degree of agreement between objective and subjective scores,measured through linear correlation,reached a value of 90%.

关键词： JPEG compression Target acquisition performance Image quality assessment Just noticeable difference Probability of target detection Target mean searching time

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Photosynthetic response to a winter heatwave in leading and trailing edge populations of the intertidal red alga Corallina offi-cinalis(Rhodophyta)

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Acta Oceanologica Sinica 2024年第7期43卷 70-77页

作者： Regina Kolzenburg Federica Ragazzola Laura Tamburello Katy R.Nicastro Christopher D.McQuaid Gerardo I.Zardi UmeåMarine sciences centre UmeåUniversity90571 NorrbynSweden University of Portsmouth Institute of Marine SciencePortsmouth PO49LYUK Stazione Zoologica Anton Dohrn Genova Marine CenterGenova 16126Italy Stazione Zoologica Anton Dohrn Sicily Marine CenterPalermo 90149Italy Department of Zoology and Entomology Rhodes UniversityMakhanda(Grahamstown)6139South Africa centre of Marine sciences University of AlgarveFaro 8005-139Portugal Laboratoire d’Océanologie et de Géosciences Universitéde LilleLille 59000France Universitéde Caen Normandie Laboratoire de Biologie des Organismes et des Ecosystèmes AquatiquesCaen 14032France

Marine heatwaves(MHWs)caused by anthropogenic climate change are becoming a key driver of change at the ecosystem *** conditions experienced by marine organisms across their distribution,particularly towards the equator,are likely to approach their physiological limits,resulting in extensive mortality and subsequent changes at the population *** at the margins of their species’distribution are thought to be more sensitive to climate-induced environmental pressures than central populations,but our understanding of variability in fitness-related physiological traits in trailing versus leading-edge populations is *** a laboratory simulation study,we tested whether two leading(Iceland)and two trailing(Spain)peripheral populations of the intertidal macroalga Corallina officinalis display different levels of maximum potential quantum efficiency(Fv/Fm)resilience to current and future winter MHWs *** study revealed that ongoing and future local winter MHWs will not negatively affect leading-edge populations of ***,which exhibited stable photosynthetic efficiency throughout the *** edge populations showed a positive though non-significant trend in photosynthetic efficiency throughout winter MHWs *** and equatorward populations did not produce significantly different results,with winter MHWs having no negative affect on Fv/Fm of either ***,we found no long-term regional or population-level influence of a winter MHWs on this species’photosynthetic ***,we found no statistically significant difference in thermal stress responses between leading and trailing ***,*** showed a trend towards higher stress responses in southern than northern *** responses rest on a variety of local population traits,they are difficult to predict based solely on thermal pressures.

关键词： marginal population coralline algae climate change ecophysiology photophysiology macroalgae Fv/Fm

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Tropical Cyclone Monitoring and Analysis Techniques: A Review

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Journal of Meteorological Research 2024年第2期38卷 351-367页

作者： Chuanhai QIAN Ying LI Yinglong XU Xin WANG Zenghai ZHANG Gaozhen NIE Da LIU Shiwen ZHANG Institute for Development and Programme design China Meteorological AdministrationBeijing 100081 Chinese Academy of Meteorological sciences China Meteorological AdministrationBeijing 100081 national Meteorological centre China Meteorological AdministrationBeijing 100081 national Satellite Meteorological centre China Meteorological AdministrationBeijing 100081

Tropical cyclones(TCs),including tropical depressions and different categories of typhoons,hurricanes,and cyclonic storms,mostly originate over the oceans in the absence of direct ***,detailed monitoring and analysis of TCs has always been an unsolved *** the recent 20 years,great changes have taken place in domestic and foreign TC monitoring techniques,imposing a significant impact on TC operations and *** new technologies and products gradually emerge to support operations,with improved monitoring *** this paper,the progress on TC monitoring and analysis via meteorological satellites,radars,and airplanes in China and the world is reviewed,compared,and summarized,with special focuses on multisatellite fusion observations,in situ aircraft measurements,and some unconventional observation equipment such as rockets,saildrones,and underwater *** this basis,the paper points out future directions for improving TC monitoring and analysis in aid of better TC forecast and early warning.

关键词： tropical cyclone(TC) monitoring and analysis meteorological satellite aircraft reconnaissance

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national Soil Organic Carbon Stocks Inventories under Different Mangrove Forest Types in Gabon

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Open Journal of Forestry 2024年第2期14卷 127-140页

作者： Rolf Gaël Mabicka Obame Neil-Yohan Musadji Jean Hervé Mve Beh Lydie-Stella Koutika Jean Aubin Ondo Farrel Nzigou Boucka Michel Mbina Mounguengui Claude Geffroy Dé partement de Phytotechnologie Institut National d&#8217Agronomie et de Biotechnologies Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Dé partement des Sciences Fondamentales de l&#8217Ing&#233nieur Institut National d&#8217Agronomie et de Biotechnologies Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Institut Agronomiques et Forestiè res Centre National des Recherches Scientifiques et Technologiques Libreville Gabon Research centre on the Durability and the Productivity of Industrial Plantations (CRDPI) Pointe Noire Republic of Congo Laboratoire Pluridisciplinaire des sciences &#201cole Normale Sup&#233rieure Libreville Gabon Agence Gabonaise d’ &#201tude et d&#8217Observation Spatiale Immeuble les Arcades Libreville Gabon Dé partement de G&#233ologie Faculte des Sciences Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Institut de Chimie des Milieux et Maté riaux de Poitiers (IC2MP) Universit&#233 de Poitiers Poitiers France

Gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear. To address this gap, determining the SOC spatial variation in Gabonese’s estuarine is essential for better understanding the global carbon cycle. The present study compared soil organic carbon between northern and southern sites in different mangrove forest, Rhizophora racemosa and Avicennia germinans. The results showed that the mean SOC stocks at 1 m depth were 256.28 ± 127.29 MgC ha−1. Among the different regions, SOC in northern zone was significantly (p p −1) than upper layers (55.42 ± 25.37 MgC ha−1). The study highlights that low deforestation rate have led to less CO2 (705.3 Mg CO2e ha−1 - 922.62 Mg CO2e ha−1) emissions than most sediment carbon-rich mangroves in the world. These results highlight the influence of soil texture and mangrove forest types on the mangrove SOC stocks. The first national comparison of soil organic carbon stocks between mangroves and upland tropical forests indicated SOC stocks were two times more in mangroves soils (51.21 ± 45.00 MgC ha−1) than primary (20.33 ± 12.7 MgC ha−1), savanna and cropland (21.71 ± 15.10 MgC ha−1). We find that mangroves in this study emit lower dioxide-carbon equivalent emissions. This study highlights the importance of national inventories of soil organic carbon and can be used as a baseline on the role of mangroves in carbon sequestration and climate change mitigation but the variation in SOC stocks indicates the need for further national data.

关键词： Mangroves Forest Soil Organic Carbon Stocks Rizophora Racemose Avicenia germinans Gabon

Experimental Study of the Thermal Behavior of a Bioclimatic Building Prototype in a Sahelian Zone

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Smart Grid and Renewable Energy 2024年第8期15卷 187-199页

作者： Arouna Kaboré Boukaré Ouédraogo Sayouba Sandwidi Vincent Zoma Hermann Kaboré Kalifa Palm Laboratoire des Energies Thermiques et Renouvelables (LetRE) Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire de Chimie Analytique Physique Spatiale et Energtique (LACAPSE) Universit Norbert ZONGO Koudougou Burkina Faso Laboratoire de Physique et Chimie de lEnvironnement Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire des Systmes dEnergie Renouvelable et Environnement Institut de Recherche en Sciences Appliques et Technologies (IRSAT) Centre National de la Recherche Scientifique et Technologique (CNRST) Ouagadougou Burkina Faso

Buildings constructed with modern materials (cement blocks, sheet metal, reinforced concrete, etc.) in the Sahelian zone often generate excessive electricity consumption and consequently very high electricity bills. This study is a contribution to the development of new building types based on the principle of bioclimatic construction. The aim is to find materials suited to the Sahelian climate and improve thermal comfort. To this end, an experimental study of the hygrothermal behavior of a bioclimatic building prototype with a domed roof is being carried out. Site meteorological data, air temperature and relative humidity of the building’s internal environment were measured for three climatic seasons in Burkina Faso. The data acquisition system consists of thermocouples, solarimeters and humidity meters, and the data are processed using Excel and Origin Pro software. The results show that, despite the high temperature values (between 36˚C and 39˚C) of the internal environment measured in the hot season, good thermal performance is achieved, in particular an average phase shift of 7.17 h and an average damping of 10.81˚C. The dome-roofed building could therefore contribute to limiting heat transmission to the building interior, improving thermal comfort all year round. Analysis of humidity profiles shows that indoor humidity varies between 66% and 80% for the September period, and between 44% and 69% for the January period. The high values of internal ambient humidity could be reduced by very good ventilation of the building. This study shows that the proposed bioclimatic building prototype with domed roof could be integrated into the Sahelian habitat.

关键词： Thermal Comfort Hygrothermal Behavior Bioclimatic Building Thermal Inertia Domed Roof

Multivariate Approach to Characterizing Soil Quality of Gabonese’s Ferralitic Soils

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Open Journal of Soil Science 2024年第4期14卷 237-268页

作者： Neil-Yohan Musadji Rolf Gaël Mabicka Obame Michel Mbina Mounguengui Jean Aubin Ondo Lydie-Stella Koutika Eric Ravire Claude Geffroy Laboratoire De Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement Des Sciences Fondamentales De L&#8217Ing&#233nieur Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Institut De Chimie des Milieux et Maté riaux De Poitiers (IC2MP) Universit&#233 De Poitiers Poitiers France Laboratoire De Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement De Phytotechnologie Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Dé partement De G&#233ologie Facult&#233 Des Sciences Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Laboratoire Pluridisciplinaire des sciences Ecole Normale Sup&#233rieure Libreville Gabon centre De Recherche Sur La Productivité et La Durabilit&#233 Des Plantations Industrielles Pointe Noire Republic of Congo Sucaf Gabon Somdiaa Franceville Gabon

Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQIadd and WQIcom) and Nemoro quality index (NQI), applied to two approaches of indicator selection: total data set (TDS) and minimum data set (MDS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of Gabon. The TDS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K+ and Mg2+, bulk density and C/N ratio were retained in MDS, using principal component analysis (PCA). In the MDS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQIadd and NQI, whereas the total was observed with WQIcom. Only 25% of provinces had medium soil quality grades with AQI and NQI models, while 12.5% (NQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQIadd and NQI into the TDS and MDS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQIadd. However, WQIadd was chosen as the best SQI model, according to its high linear regression value (R2 = 0.82) between TDS and MDS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of Gabonese soils in a pedoclimatic context unfavorable to plant growth.

关键词： Gabon Ferralitic Soil Soil Indicators Standard Score Function Soil Quality Indices Sustainable Soil Soil Management

Evaluation of a Rapid Diagnostic Test, Boson Biotech SARS CoV-2 Ag, for the Detection of SARS-CoV-2 in Gabon

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Advances in Infectious Diseases 2024年第2期14卷 469-477页

作者： Samira Zoa Assoumou Ulrich Leger Davy Mouangala Ludovic Mewono Davy-Christ Angoune Ndong Guy Paterne Malonga Mbembo Nely Meungang Alain Moutsinga Elvyre Anita Mbongo Kama Rodrigue Mintsa Nguema Dpartement de Bactriologie-Virologie Universit des Sciences de la Sant Libreville Gabon Laboratoire Professeur Daniel Gahouma Libreville Gabon Departement des sciences de la vie et de la Terre Ecole Normale Suprieure Libreville Gabon centre de sant de Glass Libreville Gabon Laboratoire national de Sant Publique Libreville Gabon Dpartement de Biologie et Ecologie Animale Centre National de la Recherche Scientifique et Technologique Libreville Gabon Laboratoire dEcologie des Maladies Transmissibles (LEMAT) Universit Libreville Nord (ULN) Libreville Gabon

1) Background: Rapid and acurate diagnostic testing for case identification, quarantine, and contact tracing is essential for managing the COVID 19 pandemic. Rapid antigen detection tests are available, however, it is important to evaluate their performances before use. We tested a rapid antigen detection of SARS-CoV-2, based on the immunochromatography (Boson Biotech SARS-CoV-2 Ag Test (Xiamen Boson Biotech Co., Ltd., China)) and the results were compared with the real time reverse transcriptase-Polymerase chain reaction (RT-PCR) (Gold standard) results;2) Methods: From November 2021 to December 2021, samples were collected from symptomatic patients and asymptomatic individuals referred for testing in a hospital during the second pandemic wave in Gabon. All these participants attending “CTA Angondjé”, a field hospital set up as part of the management of COVID-19 in Gabon. Two nasopharyngeal swabs were collected in all the patients, one for Ag test and the other for RT-PCR;3) Results: A total of 300 samples were collected from 189 symptomatic and 111 asymptomatic individuals. The sensitivity and specificity of the antigen test were 82.5% [95%CI 73.8 - 89.3] and 97.9 % [95%CI 92.2 - 98.2] respectively, and the diagnostic accuracy was 84.4% (95% CI: 79.8 - 88.3%). The antigen test was more likely to be positive for samples with RT-PCR Ct values ≤ 32, with a sensitivity of 89.8%;4) Conclusions: The Boson Biotech SARS-CoV-2 Ag Test has good sensitivity and can detect SARS-CoV-2 infection, especially among symptomatic individuals with low viral load. This test could be incorporated into efficient testing algorithms as an alternative to PCR to decrease diagnostic delays and curb viral transmission.

关键词： SARS-CoV-2 Rapid Diagnostic Test Evaluation COVID-19 Antigen Performance

Detailed Analyses of Nymphea Seeds Consumed in the Senegal River Valley

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Food and Nutrition sciences 2024年第8期15卷 695-700页

作者： Nicolas Cyrille Ayessou Michel Bakar Diop Fatou Kiné Gueye César Bassène Mame Samba Mbaye centre detudes sur la Scurit Alimentaire et les Molcules Fonctionnelles (CESAM-RESCIF) Universit Cheikh Anta DIOP Dakar Sngal Unit de formation et de Recherche des sciences Agronomiques de lAquaculture et des Technologies Alimentaires Universit Gaston Berger Saint-Louis Sngal Laboratoire de Botanique-Biodiversit Biologie Vgtale Universit Cheikh Anta Diop Dakar Senegal

Physicochemical investigations were performed on seeds of Nymphea lotus and N. micrantha consumed in the Senegal River valley. They revealed a composition similar to that of cereals. In order to estimate their intrinsic quality, the determination of their amino acid, fatty acid and monosaccharids profiles was done. The results indicate that monosaccharides are represented specifically by saccharose (7%) and glucose (0.67%);a predominance of stearic acid and linoleic acid as unsaturated acids (24.86%);arachidic and palmitic acids as the only saturated acid found (11.12%);a good ratio of unsaturated/saturated acid (2.23);a lack of oleic acid, linoleic, palmitoleic, myristic, caprylic acids;a poor-quality index protein due to low quantity amino acids. Nevertheless, all essential amino acids are present in the seeds. The Nymphea sp grains consumed by the populations around the Senegal River valley offer an interesting nutritional quality linked to fatty acids and carbohydrates.

关键词： Nymphea Seeds Composition