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Ecological Analysis of Leontice L. Species Distributed in the Navoi Region, Kyzyl-Kum Desert (Uzbekistan)

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American Journal of Plant Sciences 2024年第5期15卷 307-315页

作者： Nodirjon Bobokandov samarkand Agroinnovations and Research university Samarkand Uzbekistan

Leontice L. is a perennial herbaceous plant belonging to the Berberidaceae family. Our research was conducted in Navoi region. The article presents an ecological analysis of Leontice L. species in the Navoi region. The genus Leontice grows mainly in mountainous areas and some are distributed in arid climates. According to the information that 2 species have been identified in Navoi region, these species are plants with flavanoids healing properties. Leontice species have been used in traditional medicine since ancient times in ethnobotany. The presence of this species was discovered during the research and Leontice has identified numerous unique compounds, such as alkaloids, flavonoids, and phenolic acids, with potential medicinal properties such as anti-inflammatory, antitumor, and antiviral effects. According to ecological analysis, the Leontice genus thrives on stony, gravelly, and fine-grained mountain slopes and ridges, foothills, mountains, rocks, colorful rock outcrops, rocky slopes, and sandy, clay, and gravel deserts.

关键词： Leontice L Ecological Flavonoid Kyzyl-Kum Ethnobotany

Biology of Flowering of Some Species of the Genus Phlomoides Moench

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American Journal of Plant Sciences 2024年第4期15卷 268-273页

作者： Mukaddas Kholbutayeva Khislat Khaydarov Nodira Nurullayeva Abdurakhmonova Ezoza Kakhramon Kizi Jizzakh Polytechnic Institute Jizzakh Uzbekistan Department of Botany Samarkand State University Samarkand Uzbekistan Jizzakh state Pedagogical university Jizzakh Uzbekistan

The article presents the biology of flowering and the daily dynamics of flowering of two species from the Lamiaceae family: ph. anisochila va ph. sogdiana of the distribution out in the Nuratau Mountains range.

关键词： Phlomoides Rare and Endemic Species Nurata Mountain Systems Flowering Dynamics Abiotic Factors Cenopopulation

Synthetic brochosomes:Design,synthesis,and applications

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Nano Research 2024年第2期17卷 734-742页

作者： Lin Wang Jinsol Choi Tak-Sing Wong Department of Mechanical Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Biomedical Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA

Brochosomes,which are nanoscopic buckyball-shaped granules produced by leafhoppers,are one of the most intricate structures discovered in nature.Various functions of brochosomes have been proposed but only a few have been experimentally validated due to the challenge of fabricating their synthetic counterparts.Advancements in micro-and nanofabrication have recently led to the emergence of synthetic brochosomes,opening up new possibilities for innovative applications.This review explores the early discovery of natural brochosomes and their geometrical features,followed by the recent progress in fabricating synthetic brochosomes and their applications.Perspectives on future applications and challenges in the scalable manufacturing of synthetic brochosomes are discussed.

关键词： synthetic brochosomes leafhopper antireflection superhydrophobicity surface-enhanced Raman scattering photocatalyst energy harvesting

Analysis of synthetic parameters for coating aluminum powders with phenyltriethoxysilane coupling agent and their effects on powder flow behavior

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Particuology 2024年第7期90卷 412-417页

作者： Lillian M.Mawby Bellamarie Ludwig Benjamin J.Lear Department of Chemistry The Pennsylvania State UniversityUniversity ParkPA16802USA Applied Research Laboratory The Pennsylvania State UniversityUniversity ParkPA16802USA

Though silanization of aluminum powder is currently used to improve its flow properties,for use as an alternative fuel source,there are a wide range of experimental parameters for the process and not all of them have been thoroughly explored.Until this is complete,it is unknown if the process is optimized in terms of time,efficiency,and effect.Herein,we report on a study into the effects of changes in humidity,degree of agitation,reaction temperature,and curing time upon the deposition of phenyl triethoxysilane into 20μm(d50)aluminum particles.We confirm the deposition of the coating via diffuse reflectance infrared spectroscopy and x-ray photoelectron spectroscopy.We then characterize the coated particles using apparent density measurements and Carney flow methods.Using analysis of variance,we find that,of the parameters explored,only changes in cure time and reaction temperature provide meaningful changes to the apparent density,while none of our parameters produced statistically significant changes in Carney flow values.Thus,we conclude that,when optimizing silanization of aluminum particles,environmental control of humidity is unneeded and that the reaction can be run with minimal agitation.The ability to largely ignore these parameters is a benefit to large-scale processing.

关键词： Aluminum powder Silane Fluidization Apparent density Carney flow

Extreme Weather Disruptions and Emergency Preparedness Among Older Adults in Ohio: An Eight-County Assessment

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International Journal of Disaster Risk Science 2024年第2期15卷 213-225页

作者： Smitha Rao Fiona C.Doherty Anthony Traver Marisa Sheldon Emma Sakulich Holly Dabelko-Schoeny College of Social Work The Ohio State University Age Friendly Innovation Center College of Social Work The Ohio State University College of Public Health The Ohio State University

The disproportionate risks and impacts of climate change and extreme weather on older adults are increasingly evident. While especially true in disaster-prone areas, human-caused climate change introduces an element of uncertainty even in previously identified “safe” regions such as the Midwestern United states. Using a cumulative disadvantage and vulnerability-informed framework and descriptive statistics from multiple data sources, this article provides an overview of climate impacts, vulnerabilities, and county-level characteristics, focusing on older adults living in Central Ohio. A comparative multiple-case study methodology was used to triangulate regionally representative primary and secondary data sources to examine state and county-level measures of vulnerability, emergency preparedness, and disruptions caused by extreme weather among older adults across eight counties in Central Ohio. Seventy-eight percent of older adults in the sample reported being prepared for emergencies per Federal Emergency Management Agency guidelines. Older adults in Union County reported the highest rates of preparedness, while those in Fayette County reported the lowest. County-level rates of disruption of life activities by extreme weather ranged widely. Among the most rural in the region, Fayette County emerged as uniquely disadvantaged, with the lowest median income, the most vulnerable across multiple social vulnerability dimensions, and the most reported disruptions to life activities from extreme weather. County profiles offer a snapshot of existing vulnerabilities, socioeconomic conditions, special needs, preparedness, and current disruptions among older adults in the region and can inform resource mobilization across community and policy contexts.

关键词： Disaster preparedness Extreme weather Midwestern United states Older adults Regional assessment Social vulnerability

Theory and classification of mass extinction causation

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National Science Review 2024年第1期11卷 16-36页

作者： Thomas J.Algeo Jun Shen state Key Laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan state Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(e.***.solar flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle changes.In this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial during the Late Ordovician and Late Devonian events,

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

Roles of functionalized nanoparticles in the performance improvement of proton-exchange membranes used in low-and intermediate-temperature hydrogen fuel cells: A review

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Progress in Natural Science:Materials International 2024年第3期34卷 437-453页

作者： Abdul Salam Oksana Zholobko Xiang-Fa Wu Department of Mechanical Engineering North Dakota State University

A variety of nanoparticles（NPs）(e.g., SiO2, TiO2, CeO2, Co3O4, etc.) and their functionalized counterparts have been intensively investigated for improving the electrochemical and mechanical durability of polymer-based proton-exchange membranes（PEMs） for use in low-and intermediate-temperature fuel cells. This study is to conduct a comprehensive review on the roles of functionalized NPs in the performance enhancement of PEMs including proton conductivity, gas crossover resistance, electrochemical and mechanical durability, etc. A brief historical review of PEM fuel cell（PEMFC） technology is made. Typical types of NPs and their functionalization techniques are retrospected and their roles in the performance improvement of PEMs are compared in detail.Consequently, the opportunities and challenges to develop high-performance functionalized NPs for use in PEMs and PEMFCs are prospected and justified.

关键词： Nanocomposite Nanoparticle (NP) Proton conductivity Proton-exchange membrane (PEM) Proton-exchange membrane fuel cell (PEMFC) Surface modification

Microbes in mass extinction: an accomplice or a savior?

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National Science Review 2024年第1期11卷 12-15页

作者： Genming Luo Deng Liu Hao Yang state Key Laboratory of Geobiology and Environmental Geology China university of Geosciences (Wuhan)

Microbes include various types of organisms that are invisible to the naked eye,e.g. bacteria, archaea and microeukaryotes. Although the precise number remains largely unknown, microbes are recognized as the unseen majority of our biosphere [1]. As a group of organisms classified by body size, microbes cover a considerable spectrum of metabolisms,

关键词： AFTERMATH

Mass extinctions, their causes and consequences: an interview with Douglas H.Erwin and Shuzhong Shen

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National Science Review 2024年第1期11卷 66-70页

作者： Shucheng Xie state Key Laboratory of Biogeology and Environmental Geology China University of Geosciences at Wuhan

‘Mass extinctions’ have been a hot topic for several decades. What triggers a mass extinction? How does a mass extinction impact the evolution of life? How does our ecosystem recover after a mass extinction? These questions attracted the interest of both scientists and the public alike.NSR spoke to two renowned researchers in the field of mass extinctions: Prof. Douglas H. Erwin from the National Museum of Natural History of the USA, and Prof. Shuzhong Shen from Nanjing university, China.

关键词： Stratigraphy