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Systematic Radio Telescope Alignment Using Portable Fringe Projection Profilometry

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Nanomanufacturing and Metrology 2024年第1期7卷 75-85页

作者： Joel Berkson justin hyatt Nathan Julicher Byeongjoon Jeong Isaac Pimienta Rachel Ball Wyatt Ellis Jason Voris Diego Torres‑Barajas Daewook Kim James C.Wyant College of Optical Sciences University of Arizona1630 E.University Blvd.TucsonAZ 85721USA Department of Astronomy at Steward Observatory University of Arizona933 N Cherry Ave.TucsonAZ 85721USA

In 2019,the Event Horizon Telescope(EHT)released the first-ever image of a black hole event *** are now aiming for higher angular resolutions of distant targets,like black holes,to understand more about the fundamental laws of gravity that govern our *** achieve this higher resolution and increased sensitivity,larger radio telescopes are needed to operate at higher frequencies and in larger *** like the next-generation Very Large Array(ngVLA)and the Square-Kilometer Array(SKA)require building hundreds of telescopes with diameters greater than 10 ms over the next *** has a twofold *** telescope surfaces need to be more accurate to operate at higher frequencies,and the logistics involved in maintaining a radio telescope need to be simplified to support them properly in large *** of these problems can be solved with improved methods for surface metrology that are faster and more accurate with a higher *** leads to faster and more accurate panel alignment and,therefore,a more productive *** this paper,we present the use of binocular fringe projection profilometry as a solution to this problem and demonstrate it by aligning two panels on a 3-m radio telescope *** measurement takes only 10 min and directly delivers feedback on the tip,tilt,and piston of each panel to create the ideal reflector shape.

关键词： Metrology Fringe projection profilometry Off-axis alignment Radio astronomy Radio antenna

Astrocytes integrate time and space

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Neural Regeneration Research 2025年第2期20卷 467-468页

作者： justin Lines Department of Biological Sciences Columbia UniversityNew YorkNYUSA

Astrocytes read and react to synaptic transmission through tripartite synapses,where the binding of neurotransmitters onto astrocytic receptors triggers an increase in intracellular *** investigations have revealed that astrocytes exhibit two distinct states of intracellular calcium activity:(1)graded subcellular localized clusters with independently active microdomains,likely influenced by nearby synaptic events,and(2)whole-cell astrocyte calcium surges,believed to result from the coordinated activation of multiple ***,astrocyte calcium responses are not solely graded;instead,a spatial threshold of intracellular calcium activity can be overcome to elicit an astrocyte calcium *** these calcium responses,in turn,initiate downstream signaling pathways capable of modifying synaptic communication and overall network *** summary,astrocytes can function as integrators of local synaptic events,actively contributing to information processing within the brain.

关键词： graded integrate instead

Deciphering Water Oxidation Catalysts: The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： An, Li Li, Jianyi Sun, Yuanmiao Zhu, Jiamin Seow, justin Zhu Yeow Zhang, Hong Zhang, Nan Xi, Pinxian Xu, Zhichuan J. Yan, Chun-Hua Lanzhou Univ Frontiers Sci Ctr Rare Isotopes Key Lab Nonferrous Met Chem & Resources Utilizat G State Key Lab Appl Organ ChemColl Chem & Chem Eng Lanzhou 730000 Peoples R China Nanyang Technol Univ Sch Mat Sci & Engn Singapore 639798 Singapore Chinese Acad Sci Fac Mat Sci & Energy Engn Shenzhen Inst Adv Technol Inst Technol Carbon Neutral Shenzhen 518055 Peoples R China Yunnan Univ Natl Ctr Int Res Photoelect & Energy Mat Electron Microscopy Ctr Sch Mat & EnergyKey Lab Electromagnet Mat & Devic Kunming 650091 Peoples R China Baotou Res Inst Rare Earths State Key Lab Baiyunobo Rare Earth Resource Res & Baotou 014030 Peoples R China Peking Univ Beijing Natl Lab Mol Sci State Key Lab Rare Earth Mat Chem & Applicat PKU HKU Joint Lab Rare Earth Mat & Bioinorgan Chem Beijing 100871 Peoples R China

Demonstrate that the key factor to determine the activity of reconstructed surfaces is the surface chemistry, instead of reconstruction degree using the popular perovskite LaNi1-xFexO3 oxides as model *** content can influence both the surface reconstruction degree, the activation degree, and the activity of reconstructed *** oxygen evolution reaction activity of reconstructed catalysts is primarily governed by the chemistry of the reconstructed surface species. Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction. The surface reconstruction has been widely observed in perovskite catalysts, and the reconstruction degree has been often correlated with the activity enhancement. Here, a systematic study on the roles of Fe substitution in activation of perovskite LaNiO3 is reported. The substituting Fe content influences both current change tendency and surface reconstruction degree. LaNi0.9Fe0.1O3 is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi1-xFexO3 (x = 0.00, 0.10, 0.25, 0.50, 0.75, 1.00) series. The reconstructed LaNi0.9Fe0.1O3 shows a higher intrinsic activity than most reported NiFe-based catalysts. Besides, density functional theory calculations reveal that Fe substitution can lower the O 2p level, which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term stability. Furthermore, it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction degree. The effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface reconstruction. This finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.

关键词： Oxygen evolution reaction Perovskite oxides Doping Activation and reconstruction

Product of Functions in BMO and H1 in Non-homogeneous Spaces

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Acta Mathematica Sinica,English Series 2011年第8期27卷 1535-1546页

作者： justin FEUTO Universitd de Cocody UFR Mathdmatiques et lnformatique 22 B. P. 1194 Abidjan 22 Rgpublique de CSte d'lvoire

Under the assumption that the underlying measure is a non-negative Radon measure which only satisfies some growth condition and may not be doubling, we define the product of functions in the regular BMO and the atomic block -~1 in the sense of distribution, and show that this product may be split into two parts, one in L1 and the other in some Hardy-Orlicz space.

关键词： Local Hardy space local BMO space atomic block block non-doubling measure Hardy- Orlicz space

Removal of saxitoxin and anatoxin-a by PAC in the presence and absence of microcystin-LR and/or cyanobacterial cells

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Journal of Environmental Sciences 2023年第6期128卷 161-170页

作者： justin Rorar Laura Davila Garcia Teresa Cutright Department of Civil Engineering The University of AkronOH 44325-3905USA

Cyanobacteria can produce cyanotoxins such as microcystin-LR(MC),saxitoxin(STX),and anatoxin-a(ANTX-a)which are harmful to humans and other *** removal efficiencies of STX and ANTX-a by powdered activated carbon(PAC)was investigated,aswell as when MC-LR and cyanobacteriawere *** conductedwith distilled water and then source water,using the PAC dosages,rapid mix/flocculation mixing intensities and contact times of two drinking water treatment plants in northeast *** pH 8 and 9,STX removal was 47%-81%in distilled water and 46%-79%in source water,whereas it was 0-28%for pH 6 in distilled water and 31%-52%in source *** 1.6μg/L or 20μg/L MC-LR was present with STX,STX removal was increased with PAC simultaneously removing 45%-65%of the 1.6μg/L MC-LR and 25%-95%of the 20μg/L MC-LR depending on the ***-a removal at pH 6 was 29%-37%for distilled water and 80%for source water,whereas it was 10%-26%for pH 8 in distilled water and 28%for pH 9 in source *** presence of cyanobacteria cells decreased ANTX-a removal by at least 18%.When 20μg/L MC-LR was present with ANTX-a in source water,59%-73%ANTX-a and 48%-77%of MCLR was removed at pH 9 depending on the PAC *** general,a higher PAC dose led to higher cyanotoxin *** study also documented that multiple cyanotoxins can be effectively removed by PAC for water at pH’s between 6 and 9.

关键词： pH Cyanotoxins Cyanobacteria PAC Microcystin Saxitoxin Anatoxin-a

Mobile Home Residents and Hurricane Vulnerability in South Florida:Research Gaps and Challenges

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International Journal of Disaster Risk Science 2016年第4期7卷 436-439页

作者： Shivangi Prasad justin Stoler Department of Geography and Regional Studies University of Miami Department of Public Health Sciences Miller School of MedicineUniversity of Miami Abess Center for Ecosystem Science and Policy University of Miami

In South Florida there are several social and logistical challenges to surveying and advocating for mobile home residents regarding vulnerability to natural hazards such as sea level rise and *** residents have consequently been understudied despite historically exhibiting higher vulnerability and lower *** exploratory study uses a social-ecological framework to highlight individual-,community-,and institutional-level challenges and research gaps encountered when working with mobile home *** observations represent a longer-term opportunity to further refine our understanding of natural hazard vulnerability,build increased resilience among vulnerable populations,and improve health equity in South Florida and beyond.

关键词： Disaster preparedness Mobile homes Social-ecological model Vulnerability

Bystanders or not?Microglia and lymphocytes in aging and stroke

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Neural Regeneration Research 2023年第7期18卷 1397-1403页

作者： justin N.Nguyen Anjali Chauhan University of Texas McGovern Medical School at Houston HoustonTXUSA Department of Neurology University of Texas McGovern Medical School at HoustonHoustonTXUSA

As the average age of the world population increases,more people will face debilitating aging-associated conditions,including dementia and *** only does the incidence of these conditions increase with age,but the recovery afterward is often worse in older *** and health professionals must unveil and understand the factors behind age-associated diseases to develop a therapy for older *** causes profound changes in the immune system including the activation of microglia in the *** microglia promote T lymphocyte transmigration leading to an increase in neuroinflammation,white matter damage,and cognitive impairment in both older humans and *** presence of T and B lymphocytes is observed in the aged brain and correlates with worse stroke *** strategies in stroke target either microglia or the lymphocytes or the communications between them to promote functional recovery in aged *** this review,we examine the role of the microglia and T and B lymphocytes in aging and how they contribute to cognitive ***,we provide an important update on the contribution of these cells and their interactions in preclinical aged stroke.

关键词： age B lymphocytes brain central nervous system cognition inflammation microglia middle cerebral artery occlusion neuroinflammation stroke T lymphocytes white matter injury

Impact of pediatric traumatic brain injury on hippocampal neurogenesis

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Neural Regeneration Research 2021年第5期16卷 926-933页

作者： Mariam Rizk justin Vu Zhi Zhang Department of Natural Sciences University of Michigan-DearbornDearbornMIUSA

Traumatic brain injury(TBI)is a major cause of mortality and morbidity in the pediatric *** advances in medical care,the mortality rate of pediatric TBI has ***,more children and adolescents are living with TBI-related cognitive and emotional impairments,which negatively affects the quality of their *** hippocampal neurogenesis plays an important role in cognition and mood *** in adult hippocampal neurogenesis are associated with a variety of neurological and neurodegenerative diseases,including *** endogenous hippocampal neurogenesis after TBI merits significant ***,TBI affects the function of neural stem/progenitor cells in the dentate gyrus of hippocampus,which results in aberrant migration and impaired dendrite development of adult-born ***,a better understanding of adult hippocampal neurogenesis after TBI can facilitate a more successful neuro-restoration of damage in immature *** injuries,such as neuroinflammation and oxidative stress,exert a significant impact on hippocampal ***,a variety of therapeutic approaches have been proposed for ameliorating secondary TBI *** this review,we discuss the uniqueness of pediatric TBI,adult hippocampal neurogenesis after pediatric TBI,and current efforts that promote neuroprotection to the developing brains,which can be leveraged to facilitate neuroregeneration.

关键词： adult hippocampal neurogenesis astrocytes development microglia neuroinflammation neuroregeneration oxidative stress pediatric traumatic brain injury plasticity stem cell

Molecular Mechanisms Regulating Rapid Stress Signaling Networks in Arabidopsis

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Journal of Integrative Plant Biology 2010年第4期52卷 354-359页

作者： justin W. Walley Katayoon Dehesh Department of Plant Biology University of California Division of Biological Sciences University of California

As sessile organisms plants must ronmental conditions. To survive cope with ever changing enviplants have evolved elaborate mechanisms to perceive and rapidly respond to a diverse range of abiotic and biotic stresses. Central to this response is the ability to modulate gene expression at both the transcriptional and posttranscriptional levels. This review will focus on recent progress that has been made towards understanding the rapid reprogramming of the transcriptome that occurs in response to stress as well as emerging mechanisms underpinning the reprogramming of gene expression in response to stress,

关键词： Molecular Mechanisms Regulating Rapid Stress Signaling Networks in Arabidopsis CAF