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Nano Research 2024年第3期17卷 1251-1258页

作者： Zhe Li Tobias K.Misicko Fan Yang Xiaopeng Liu Zhenwei Wu Xiaoyang Gao Tao Ma Jeffrey T.Miller daniela S.Mainardi Collin D.Wick Zhenhua Zeng Yang Xiao Yue Wu Department of Chemical and Biological Engineering Iowa State University618 Bissell RoadAmesIA 50011USA Institute for Micromanufacturing Louisiana Tech University505 Tech DriveRustonLA 71272USA Davidson School of Chemical Engineering Purdue University480 Stadium Mall DriveWest LafayetteIN 47907USA Michigan Center for Materials Characterization University of Michigan2800 Plymouth RdAnn Arbor MI 48109USA College of Engineering and Science Louisiana Tech UniversityRustonLA 71272USA

Atomically thin Pt nanolayers were synthesized on the surface of Mo2TiC2 MXenes and used for the catalytic dehydrogenation of ethane and propane into ethylene and propylene,two important chemicals for the petrochemical industry.As compared with Pt nanoparticles,the atomically thin Pt nanolayer catalyst showed superior coke-resistance(no deactivation for 24 h),high activity(turnover frequencies(TOFs)of 0.4–1.2 s^(-1)),and selectivity(>95%)toward ethylene and propylene.The unique Pt nanolayer has a similar geometric surface to Pt nanoparticles,enabling the investigations of the electronic effect on the catalytic performance,where the geometric effect is negligible.It is found that the electronic effect plays a critical role in dehydrogenative product selectivity and catalyst stability.The metal–support interaction is found dependent on the substrate and metal components,providing wide opportunities to explore high-performance MXene-supported metallic catalysts.

关键词： MXene catalysis alkane dehydrogenation nanolayers

Dielectric spectroscopy characterization of Naþ ion-conducting polymer nanocomposite system PEO–PVP–NaIO_(4)–TiO_(2)

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Journal of Advanced Dielectrics 2024年第1期14卷 59-73页

作者： Georgi B.Hadjichristov daniela G.Kovacheva Yordan G.Marinov daniela B.Karashanova Todor E.Vlakhov Nicola Scaramuzza Georgi Nadjakov Institute of Solid State Physics Bulgarian Academy of Sciences 72 Tzarigradsko Chaussee Blvd.BG-1784 SofiaBulgaria Institute of General and Inorganic Chemistry Bulgarian Academy of Sciences Acad.Georgi Bonchev Str. 11 bd.BG-1113 SofiaBulgaria Institute of Optical Materials and Technologies“Acad.Jordan Malinowski” Bulgarian Academy of Sciences Acad.Georgi Bonchev Str.bl.109BG-1113 SofiaBulgaria Dipartimento di Fisica Universita degli Studi della Calabria Via P.BucciCubo 33BRende(CS)IT-87036Italy

We studied the effect of titanium dioxide(TiO_(2))nanoparticles(NPs)on dielectric behavior of Naþion-conducting salt-complexed polymer nanocomposite system formed from a binary polymer blend of poly(ethylene oxide)(PEO)and polyvinyl pyrrolidone(PVP),with the addition of both sodium metaperiodate(NaIO_(4))at concentration 10 wt.%and TiO_(2) NPs of size10 nm,at concentrations 1,2,3,4 and 5 wt.%.Free standing nanocomposite PEO/PVP/NaIO_(4)/TiO_(2) films(150m)were characterized at room-temperature by analyzing their complex electrical impedance and dielectric spectra in the range 1 Hz–1 MHz.At the concentration of 3 wt.%of TiO_(2) NPs,both ion conductivity and dielectric permittivity of the PEO/PVP/NaIO_(4)/TiO_(2) ion-conducting dielectrics reach an enhancement by more than one order of magnitude as compared to nanoadditive-free case.

关键词： Dielectric properties sodium-ion-polymer electrolyte systems titanium dioxide(TiO_(2))nanoparticles nanocomposites KWW model

Update on the use of 45S5 bioactive glass in the treatment of bone defects in regenerative medicine

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World Journal of Orthopedics 2024年第3期15卷 204-214页

作者： Dayane Maria Braz Nogueira Marcelie Priscila de Oliveira Rosso daniela Vieira Buchaim Mariana Schutzer Ragghianti Zangrando Rogério Leone Buchaim Department of Prosthodontics and Periodontics Bauru School of DentistryUniversity of São PauloBauru 17012-901Brazil Department of Biological Sciences Bauru School of DentistryUniversity of São PauloBauru 17012-901Brazil Medical School University Center of AdamantinaAdamantina 17800-000Brazil Postgraduate Program in Structural and Functional Interactions in Rehabilitation Postgraduate DepartmentUniversity of MaríliaMarília 17525-902Brazil

Bone regeneration is a critical area in regenerative medicine,particularly in orthopedics,demanding effective biomedical materials for treating bone defects.45S5 bioactive glass(45S5 BG)is a promising material because of its osteoconductive and bioactive properties.As research in this field continues to advance,keeping up-to-date on the latest and most successful applications of this material is imperative.To achieve this,we conducted a comprehensive search on Pub-Med/MEDLINE,focusing on English articles published in the last decade.Our search used the keywords“bioglass 45S5 AND bone defect”in combination.We found 27 articles,and after applying the inclusion criteria,we selected 15 studies for detailed examination.Most of these studies compared 45S5 BG with other cement or scaffold materials.These comparisons demonstrate that the addition of various composites enhances cellular biocompatibility,as evidenced by the cells and their osteogenic potential.Moreover,the use of 45S5 BG is enhanced by its antimicrobial properties,opening avenues for additional investigations and applications of this biomaterial.

关键词： Biocompatible materials Bioglass Bone regeneration

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星巴克人手不足导致顾客不满

商业周刊（中文版） 2024年第10期 12-14页

作者： daniela Sirtori 孟洁冰(译) 不详

星巴克的员工表示,人手不足导致顾客等待时间升、订单未完成和销量下降。星巴克的咖啡师说,他们正面临一个令人担忧的问题:饮品订单接而至,但制作饮品的人却越来越少。据员工和经理透露,在一些门店,一年前还有五个人制作冰玛奇朵和双份... 详细信息

星巴克的员工表示,人手不足导致顾客等待时间升、订单未完成和销量下降。星巴克的咖啡师说,他们正面临一个令人担忧的问题:饮品订单接而至,但制作饮品的人却越来越少。据员工和经理透露,在一些门店,一年前还有五个人制作冰玛奇朵和双份浓缩咖啡,而现在只剩下三四个人,这些知情人因未获授权公开发言而要求不具名。

关键词：星巴克顾客等待时间门店顾客不满不具名知情人饮品订单

Analysis of Changes of Extreme Temperature during June to August Season over Tanzania

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Journal of Geoscience and Environment Protection 2024年第2期12卷 44-56页

作者： Justus Renatus Mbawala Huixin Li Jiani Zeng Daudi Mikidadi Ndabagenga Anqin Tan daniela Janine Beukes Praksed Mrosso Rafael Samuel Ekwacu Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/School of Atmospheric Sciences Nanjing University of Information Science and Technology Nanjing China National Meteorological Training Centre Kigoma Tanzania Tanzania Meteorological Authority (TMA) Forecasting Office Kilimanjaro International Airport (KIA) Kilimanjaro Tanzania Namibia Meteorological Service Windhoek Namibia Uganda National Meteorological Authority Kampala Uganda

Natural and human systems are exposed and vulnerable to climate extremes, which contributes to the repercussions of climate variability and the probability of disasters. The impacts of both natural and human-caused climate variability are reflected in the reported changes in climate extremes. Particularly at the local community levels in the majority of the regions, there is currently a dearth of information regarding the distribution, dynamics, and trends of excessive temperatures among the majority of Tanzanians. Over the years 1982-2022, this study examined trends in Tanzania’s extreme temperature over the June to August season. Based on the distinction between absolute and percentile extreme temperatures, a total of eight ETCCDI climate indices were chosen. Mann-Kendall test was used to assess the presence of trends in extreme climatic indices and the Sen’s Slope was applied to compute the extent of the trends in temperature extremes. The study showed that in most regions, there is significant increase of warm days and nights while the significant decrease of cold days and nights was evident to most areas. Moreover, nighttime warming surpasses daytime warming in the study area. The study suggests that anthropogenic influences may contribute to the warming trend observed in extreme daily minimum and maximum temperatures globally, with Tanzania potentially affected, as indicated in the current research. The overall results of this study reflect patterns observed in various regions worldwide, where warm days and nights are on the rise while cold days and nights are diminishing.

关键词： Indices Warm Days and Nights Cold Days and Nights ECA&D Tanzania

Geophysical evidence of a large occurrence of mud volcanoes associated with gas plumbing system in the Ross Sea(Antarctica)

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Geoscience Frontiers 2024年第1期15卷 304-324页

作者： Martina Busetti Riccardo Geletti Dario Civile Chiara Sauli Giuseppe Brancatelli Edy Forlin daniela Accettella Lorenza Barro Savonuzzi Laura De Santis Aldo Vesnaver Andrea Cova National Institute of Oceanography and Applied Geophysics–OGS Borgo Grotta Gigante 42/c34010 SgonicoTriesteItaly

Seafloor and buried reliefs occur along continental margin of the Ross Sea(Antarctica).These features are several kilometres wide and tens of metres high,exhibiting cone or flat-top dome shapes.Previous studies have proposed a volcanic or glacial origin for these formations,but these hypotheses do not account for all the available evidence.In this study,we use morpho-bathymetric data,intermediate resolution multichannel seismic and high resolution chirp profiles,as well as magnetic lines to investigate these clusters of mounds.By employing targeted processing techniques to enhance the geophysical characterization of the seafloor and buried reliefs,and to understand the underlying geological features,we propose that the reliefs are mud volcanoes.Some of these formations appear to be associated with a plumbing system,as indicated by acoustic anomalies linked to sediment containing gas.These formations are likely fed by clayey source rocks of Miocene age.Additionally,other reliefs might be the result of mud mobilisation caused by gravity instability and fluid overpressure.

关键词： Ross Sea Antarctica Mud volcanoes Gas plumbing system Gas hydrate Bottom Simulating Reflector

Broad Hormonal Responses Induced by Aluminum in Roots of Dwarf Transgenics of Solanum lycopersicum L. cv “Micro-Tom”

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American Journal of Plant Sciences 2024年第5期15卷 349-358页

作者： Arthur B. Rates daniela Boanares Daniele S. G. Pianetti Felipe Della-Torre Joni E. Lima Marcel G. C. França Department of Botany and Plant Physiology Laboratory Federal University of Minas Gerais Belo Horizonte Brazil

The spatial pattern distribution of plant hormones in response to aluminum (Al) toxicity in roots remains to be shown. This study was performed to assess the root hormonal accumulation and gene expression in response to Al toxicity in five transgenic miniature dwarf tomatoes cv. Micro-Tom (MT). MT and MT transgenics to acid indole acetic, cytokinin, gibberellin, abscisic acid and ethylene were cultivated in nutrient solutions containing different Al concentrations. Root growth elongation was measured and cellular damage was visualized by staining Evans’s blue. The GUS reporter gene staining technique was used to visualize hormonal changes in MT apex root tissues. Data indicated that the MT is sensitive to Al that induced significant growth inhibition and cellular damage. Al concentration of 27 μM was significantly toxic, inducing root apex darkening and inhibition of root development. The qualitative evaluation of GUS reporter gene expression showed intense crosstalk among all hormones studied, underscoring the complexity of signaling induced by Al in apex roots. Results point out to a major understanding of the hormonal signaling in response to Al toxicity, which may induce a change of root growth and architecture with growth inhibition and cell constraints modulated by all different hormones evaluated.

关键词： Gene Reporter Metal Plant Hormones Root Staining

Relationship between the rs2241766 ADIPOQ Polymorphism in a Black African Population and the Occurrence of Type 2 Diabetes

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American Journal of Molecular Biology 2024年第2期14卷 97-106页

作者： Aude Syntia Mbang Bengone Rosalie Nikiema-Ndong Elisabeth Lendoye Alvine Sibylle Batou Edwige Nnegue Edzo Serge Bekale daniela Nsame Frédéric Da Dari Félix Ovono Abessolo Department of Chemistry-Biochemistry Faculty of Medicine University of Health Sciences Libreville Gabon Laboratory of Research in Biochemistry (LAREBIO) University of Sciences and Technology of Masuku Franceville Gabon Endocrinology Department University Hospital of Libreville Libreville Gabon Research Institute of Health Sciences Bobodioulasso Burkina Faso

Background: Type 2 diabetes mellitus (T2DM) is a metabolic disease, characterized by chronic hyperglycemia. This pathology is linked to various genes whose interaction with the environment promotes its development. The aim of this work was to determine the relationship between the rs2241766 (T/G) polymorphism of the ADIPOQ gene with type 2 diabetes in the black population. Material and Methods: This work was a case-control study, involving type 2 diabetics subjects (n = 94) and controls (n = 82). The study took place from September 2022 to September 2023. Patients were recruited in the Endocrinology Department of the Libreville University Hospital Center. Analysis was performed in the Biochemistry laboratory of the University of Health Sciences in Libreville and at the Research Institute of Health Sciences of Bobodioulasso. Genomic DNA was extracted using the protocol Qiagen kit and the PCR-RFLP method was used to determine the rs2241766 (T/G) polymorphism of the ADIPOQ gene. Results: Only 2 genotypes were found in this population, the TT genotype and the GT genotype. The proportions were not different between the two groups (p = 0.1095) neither the distribution of G and T alleles (p = 0.1095). On the other hand, the HDL hypocholesterolemia was frequent in subjects with the GT genotype compared to TT heterozygous (51.1% vs 48.9%, p = 0.0280;OR = 0.55 [0.30 - 1.01]). Conclusion: There was no association between the rs2241766 (T/G) variant of the ADIPOQ gene and the occurrence of type 2 diabetes in this population. On the other hand, a relationship between HDL hypocholesterolemia and the GT genotype has been established.

关键词： Type 2 Diabetes Mellitus Polymorphism rs2241766 ADIPOQ PCR-RFLP

Early estimation of the number of hidden HIV infected subjects: An extended Kalman filter approach

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Infectious Disease Modelling 2023年第2期8卷 341-355页

作者： Paolo Di Giamberardino daniela Iacoviello Dept.of Computer Control and Management EngineeringSapienzaUniversity of RomeVia Ariosto 2500185RomeItaly

In the last decades several epidemic emergencies have been affecting the world,influencing the social relationships,the economics and the habits.In particular,starting in the early 080,the Acquired Immunodeficiency Syndrome,AIDS,is representing one of the most worrying sanitary emergency,that has caused up to now more than 25 million of dead patients.The infection is caused by the Human Immunodeficiency Virus,HIV,that may be transmitted by body fluids;therefore with wise behaviours the epidemic spread could rapidly be contained.This sanitary emergency is peculiar for the long incubation time:it can reach even 10 years,a long period in which the individual can unconsciously infect other subjects.The identification of the number of infected unaware people,mandatory to define suitable containment measures,is here obtained by using the extended Kalman filter applied to a noisy model in which,reasonably,only the number of infected diagnosed patients is available.Numerical simulations and real data analysis support the effectiveness of the approach.

关键词： Epidemic modeling Infection spread HIV-AIDS Extended Kalman filter

Disaster Risk Governance as Assemblage: The Chilean Framework of the 1985 San Antonio Earthquake

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International Journal of Disaster Risk Science 2022年第6期13卷 878-889页

作者： daniela P.González Architecture and Urban Studies Pontifcal Catholic University of Chile7520245 SantiagoChile

The purpose of this article is to analyze disaster risk governance through assemblage theory, identifying how-during the altered political context of a military regime with a centralized disaster risk management as in the case of Chile in 1985-new actors emerge during the disaster response phase as a de/reterritorialization effect that is influenced by their agencies and relationships, disfiguring the edges of the assemblage. Based on this conceptualization, it is possible to investigate the interactions between the different actors, their power relations, and their reconfigurations in the governance exercise. For this purpose, we reviewed the response phase of the 1985 San Antonio earthquake that affected the central zone of Chile, where strategic functions, institutions, and forms of power are concentrated.To describe and visualize the actors during the response phase in the disaster risk governance framework, a map of actors was developed that identifies the existing relationships and their different weights. The central scale proved to be dominant and occupied a political space that was transfigured by its overrepresentation-enforced by allies such as the banking system and business associations-enhancing a neoliberal agenda. The leaps in scale from the central scale to the local scale cancel agency of the last, destabilizing its capacity to deal with the effects of the earthquake and isolating it from the decision-making processes. Consequently,delays in providing aid demonstrate that authoritarian governments do not provide better management in the disaster response phase.

关键词： Assemblage Chile Disaster response phase Disaster risk governance San Antonio earthquake