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Summary of a Life in Observational Ultraviolet/Optical Astronomy

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Research in Astronomy and Astrophysics 2024年第1期24卷 1-43页

作者： Donald g.York Department of Astronomy and Astrophysics The University of Chicago5801 South Ellis Ave.Chicago 60637ILUSA

i reminisce on my early life in Section 1;on my education in Sections 2 and 3;on the years at Princeton as a research astronomer in Section 4;on the years on the faculty at Chicago in Section 5;on research on Diffuse interstellar Bands(DiBs) in Section 6;on construction of the 3.5 m telescope at Apache Point Observatory(APO)in Section 7;on work on the Sloan Digital Sky Survey(SDSS) in Section 8;on work in public education in Chicago in Section 9;and on my travels in Section 10. My main science research is of an observational nature,concerni.g.galactic and intergalactic interstellar gas. Highlights for me included my work on the orbiti.g.telescope Copernicus, includi.g.the discovery of interstellar deuterium;early observations of absorption associated with fivetimes ionized oxygen;and discoveries concerni.g.the phases of gas in the local interstellar medium, based on previously unobservable interstellar UV spectral lines. With other instruments and collaborations, i extended interstellar UV studies to the intergalactic cool gas usi.g.quasi-stellar object QSO absorption lines redshifted to the optical part of the spectrum;provided a better definition of the emission and morphological character of the source of absorption lines in QSO spectra;and pursued the identification of the unidentified DiBs. For several of these topics, extensive collaborations with many scientists were essential over many years. The conclusions developed slowly, as i moved from bei.g.a graduate student at Chicago, to a research scientist position at Princeton and then to a faculty position at Chicago. At each stage of life, i was exposed to new technologies adaptable to my science and to subsequent projects. From high school days, i encountered several management opportunities which were formative. i have been extremely fortunate both in scientific mentors i had and in experimental opportunities i encountered.

关键词： interstellar Medium(iSM) Nebulae (galaxies:)quasars:absorption lines ultraviolet:stars

Rice Husk at a glance:From Agro-industrial to Modern Applications

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Rice science 2024年第1期31卷 14-32页

作者： Masoumeh KORDi Naser FARROKHi Martin i.PECH-CANUL Asadollah AHMADiKHAH Department of Cell&Molecular Biology Faculty of Life Sciences and BiotechnologyShahid Beheshti UniversityTehran ***Iran 1062 Metallurgical industry Avenue Industrial Park Saltillo-Ramos ArizpeRamos ArizpeCoahuila 25900Mexico

Excessive waste production has led to the concept of a circular bioeconomy to deliver valuable by-products and improve environmental *** annual worldwide rice production accounts for more than 750 million tons of grain and 150 million tons of *** husk(RH)contains valuable biomaterials with extensive applications in various *** proportions of each component depend primarily on rice genotype,soil chemistry,and climatic *** and its derivatives,includi.g.ash,biochar,hydrochar,and activated carbon have been placed foreground of applications in agriculture and other *** the investigation on RH’s compositions,microstructures,and by-products has been done copiously,owi.g.to its unique features,it is still an open-ended area with enormous scope for innovation,research,and ***,we reviewed the latest applications of RH and its derivatives,includi.g.fuel and other energy resources,construction materials,pharmacy,medicine,and nanobiotechnology to keep this versatile biomaterial in the spotlight.

关键词： circular bioeconomy rice husk activated carbon rice husk ash rice husk biochar rice husk hydrochar rice husk application

A facile strategy for tuni.g.the density of surface-grafted biomolecules for melt extrusion-based additive manufacturi.g.applications

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Bio-Design and Manufacturing 2024年第3期7卷 277-291页

作者： i.A.O.Beeren g.Dos Santos P.J.Dijkstra C.Mota J.Bauer H.Ferreira Rui L.Reis N.Neves S.Camarero-Espinosa M.B.Baker L.Moroni Department of Complex Tissue Regeneration MERLN Institute for Technology-Inspired Regenerative MedicineMaastricht University6229 ER MaastrichtThe Netherlands 3B’s Research group I3Bs–Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal iCVS/3B’s-PT government Associate Laboratory 4806-909 Braga/GuimarãesPortugal POLYMAT University of the Basque Country UPV/EHU20018 Donostia/San SebastiánSpain iKERBASQUE Basque Foundation for Science48009 BilbaoSpain

Melt extrusion-based additive manufacturi.g.ME-AM)is a promisi.g.technique to fabricate porous scaffolds for tissue engi-neeri.g.***,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control cell *** of biomolecules on polymeric surfaces of AM scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface ***,we report a strategy to tune the surface density of bioactive groups by blendi.g.a low molecular weight poly(ε-caprolactone)5k(PCL5k)containi.g.orthogonally reactive azide groups with an unfunctionalized high molecular weight PCL75k at different *** porous three-dimensional(3D)scaf-folds were then fabricated usi.g.a high weight percentage(75 wt.%)of the low molecular weight PCL *** a proof-of-concept test,we prepared films of three different mass ratios of low and high molecular weight polymers with a thermopress and reacted with an alkynated fluorescent model compound on the surface,yieldi.g.a density of 201-561 pmol/cm^(2).Subsequently,a bone morphogenetic protein 2(BMP-2)-derived peptide was grafted onto the films comprisi.g.different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal cells(hMSCs)was *** two weeks of culturi.g.in a basic medium,cells expressed higher levels of BMP receptor ii(BMPRii)on films with the conjugated *** addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-i.g.the highest peptide density(i.e.,561 pmol/cm^(2)),indicati.g.the importance of the surface *** together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material ***,we have presented a viable strategy for ME-AM community that desires to tune the bulk and surface functionality via blendi.g.of(m

关键词： Additive manufacturing Blending Surface functionalization Surface density Click chemistry Human

A Statistical Study of Magnetic Flux Emergence in Solar Active Regions Prior to Strongest Flares

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Research in Astronomy and Astrophysics 2024年第4期24卷 147-160页

作者： Alexander S.Kutsenko Valentina i.Abramenko Andrei A.Plotnikov Crimean Astrophysical Observatory p/o NauchnyCrimea298409Russia

Usi.g.the data on magnetic field maps and continuum intensity for Solar Cycles 23 and 24,we explored 100 active regions(ARs)that produced M5.0 or stronger *** focus on the presence/absence of the emergence of magnetic flux in these ARs 2-3 days before the strong flare *** found that 29 ARs in the sample emerged monotonically amidst quiet-Sun.A major emergence of a new magnetic flux within a pre-existi.g.AR yieldi.g.the formation of a complex flare-productive configuration was observed in another 24 *** 30 ARs,an insignificant(in terms of the total magnetic flux of pre-existi.g.AR)emergence of a new magnetic flux within the pre-existi.g.magnetic configuration was observed;for some of them the emergence resulted in a formation of a configuration with a small δ-sunspot;11 out of 100 ARs exhibited no signatures of magnetic flux emergence duri.g.the entire interval of *** six cases the emergence was in progress when the AR appeared on the Eastern limb,so that the classification and timi.g.of emergence were not *** conclude that the recent flux emergence is not a necessary and/or sufficient condition for strong flari.g.of an *** flux emergence rate of flare-productive ARs analyzed here was compared with that of flare-quiet ARs analyzed in our previous *** revealed that the flare-productive ARs tend to display faster emergence than the flare-quiet ones do.

关键词： Sun:activity Sun:flares Sun:magnetic fields

Radiative loss of coherence in free electrons:a long-range quantum phenomenon

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Light(Science & Applications) 2024年第2期13卷 294-301页

作者： Cruz i.Velasco Valerio Di.g.ulio F.Javier garcía de Abajo iCFO-institut de Ciencies Fotoniques The Barcelona Institute of Science and Technology08860Castelldefels(Barcelona)Spain iCREA-institucióCatalana de Recerca i Estudis Avançats Passeig Lluís Companys 2308010BarcelonaSpain

Quantum physics rules the dynamics of small objects as they interact over microscopic length ***,quantum correlations involvi.g.macroscopic distances can be observed between entangled photons as well as in atomic gases and matter waves at low *** long-range nature of the electromagnetic coupli.g.between charged particles and extended objects could also tri.g.r quantum phenomena over large ***,we reveal a manifestation of quantum mechanics that involves macroscopic distances and results in a nearly complete depletion of coherence associated with which-way free-electron interference produced by electron-radiation coupli.g.in the presence of distant extended *** is a ubiquitous effect that we illustrate through a rigorous theoretical analysis of a two-path electron beam interacti.g.with a semi-infinite metallic plate and find the inter-path coherence to vanish proportionally to the path separation at zero temperature and exponentially at finite *** investigated regime of large distances originates in the coupli.g.of the electron to radiative modes assisted by diffraction at material structures but without any involvement of material *** the fundamental interest of this macroscopic quantum phenomenon,our results suggest an approach to measuri.g.the vacuum temperature and nondestructively sensi.g.the presence of distant objects.

关键词： temperature quantum macroscopic

Approach for C1 to C2 products commenci.g.from carbon dioxide: A brief review

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PETROLEUM 2024年第3期10卷 373-398页

作者： Dey, g. R. Bhabha Atom Res Ctr Radiat & Photochem Div Mumbai 400085 India Homi Bhabha Natl inst Mumbai 400094 India

The carbon dioxide (CO2) conversion to useable compounds remains a great contest to scientists, engineers, and environmentalists with regard to the reverse of the oxidative degradation of organics. This conversion is essential for the development of complementary fuels and raw materials for various industries, which in turn will help in avoidi.g.the drastic increase in tropospheric temperature due to greenhouse effect leadi.g.to global warmi.g. The solar energy is the earth's essential power source along with the other various forms of energy for example fossil fuels, hydropower, wind, and biomaterials, etc. The final goal is to establish the artificial photosynthesis, which can be replicated thru various chemical reduction techniques of CO2 by employi.g.appropriate photo-, thermal- and electro-catalysts in order to produce different one carbon atom (C-1) and higher carbon atoms containi.g.products. Besides, the utilization of clean and sustainable CO2 towards high-value products is of great interest today due to the recognized environmental worries and subsequent lesseni.g.of the fossil fuels utilization load to meet the energy demand of mankind. This way, solar energy can directly and/or indirectly be altered and stored in chemical energy form for industrial as well as societal applications. in this article our endeavor is to summarize the advances in CO2 chemical reduction research area till date especially in free radical-based methods such as electrochemical, photochemical and plasma chemical for the development of carbon species up to two carbon (C-2) atoms containi.g.products perceived in the chemical reduction of CO2. The author hopes that this piece of work will be helpful to researchers and readers who are focused on the field of CO2.

关键词： Photocatalysis Electrocatalysis Plasmolysis Thermolysis Carbon dioxide Chemical reduction PHOTOCATALYTiC CO2 REDUCTiON gAS SHiFT REACTiON METAL-ORgANiC FRAMEWORKS EFFiCiENT ELECTROCHEMiCAL REDUCTiON DiELECTRiC-BARRiER DiSCHARgES iON-EXCHANgE MEMBRANES FORMiC-ACiD ELECTROCATALYTiC REDUCTiON ATMOSPHERiC-PRESSURE ROOM-TEMPERATURE

From the dust:extracellular vesicles as regulators of development and neuroregeneration

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Neural Regeneration Research 2024年第5期19卷 933-934页

作者： Leon g.Coleman Jr The University of North Carolina at Chapel Hill School of MedicineDepartment of PharmacologyBowles Center for Alcohol StudiesChapel HillNCUSA

First impressions can have a lasti.g.*** science,this can be especially problematic,because our lack of understandi.g.often causes us to mislabel and thus ignore important biological *** this vein,extracellular vesicles(EVs)were once considered to be“cellular dust”.Similar to the previous concept of“junk DNA”to describe protein non-codi.g.regions,EVs are far more than just cellular *** fact,EVs are emergi.g.as key mediators of intracellular communication across nearly all biological *** includes peripheral immune responses(e.g.,arthropathies and sepsis),intra-organ communication(Seim et al.,2023),and a host of other physiological and pathological states(Figure 1A and B).

关键词： Figure extracellular

Endotoxin-induced alterations of adipose tissue function:a pathway to bovine metabolic stress

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1391-1407页

作者： Miguel Chirivi.g.Andres Contreras Department of Large Animal Clinical Sciences Michigan State UniversityEast LansingMIUSA

Duri.g.the periparturient period, dairy cows exhibit negative energy balance due to limited appetite and increased energy requirements for lactogenesis. The delicate equilibrium between energy availability and expenditure puts cows in a state of metabolic stress characterized by excessive lipolysis in white adipose tissues(AT), increased production of reactive oxygen species, and immune cell dysfunction. Metabolic stress, especially in AT, increases the risk for metabolic and inflammatory diseases. Around parturition, cows are also susceptible to endotoxemia. Bacterial-derived toxins cause endotoxemia by promoti.g.inflammatory processes and immune cell infiltration in different organs and systems while impacti.g.metabolic function by alteri.g.lipolysis, mitochondrial activity, and insulin sensitivity. in dairy cows, endotoxins enter the bloodstream after overcomi.g.the defense mechanisms of the epithelial barriers, particularly duri.g.common periparturient conditions such as mastitis, metritis, and pneumonia, or after abrupt changes in the gut microbiome. in the bovine AT, endotoxins induce a pro-inflammatory response and stimulate lipolysis in AT, leadi.g.to the release of free fatty acids into the bloodstream. When excessive and protracted, endotoxin-induced lipolysis can impair adipocyte's insulin signali.g.pathways and lipid synthesis. Endotoxin exposure can also induce oxidative stress in AT through the production of reactive oxygen species by inflammatory cells and other cellular components. This review provides insights into endotoxins' impact on AT function, highlighti.g.the gaps in our knowledge of the mechanisms underlyi.g.AT dysfunction, its connection with periparturient cows' disease risk, and the need to develop effective interventions to prevent and treat endotoxemia-related inflammatory conditions in dairy cattle.

关键词： Adipose tissue dysfunction Endotoxin inflammation insulin resistance

interpreti.g.siliciclastic sedimentation in the upper Paleozoic Mulargia-Escalaplano Basin(Sardinia, italy):influence of tectonics on provenance

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Journal of Palaeogeography 2024年第1期13卷 18-34页

作者： Luca g.Costamagna Sara Criniti Dipartimento di Scienze Chimiche e geologiche Citadella UniversitariaBlocco A09042 Monserrato CAItaly Dipartimento di i.g.gneria dell'Ambiente Universita della Calabria87036 Arcavacata di Rende CSItaly

Late to post-Variscan molassic basins of Late Pennsylvanian-Permian age are exposed in Sardinia(italy). Here, the compositional and stratigraphic evolution of the Mulargia-Escalaplano sedimentary basin(central Sardinia) has been investigated to highlight how the tectono-magmatic processes have influenced the sedimentation. Ruditic and arenitic samples were collected along well-characterized stratigraphic sections to provide a new insight into the impact of the tectono-magmatic processes on siliciclastic sedimentation. As a result, the conglomerates are mainly clast-supported, petromictic, and thus immature, with no defined maturity trend upwards. Nevertheless, pebble composition changes in times from Variscan basement pebble-rich to volcanic rock-rich, as a consequence of the basin wideni.g.and the dismantli.g.and reworki.g.of the coeval volcanic activity. The sandstone composition clearly changes from quartzolithic to feldspatholithic upwards, as a response to the same change of feedi.g.and reworki.g.of the volcanic rocks. Occasionally, interbedded quartzolithic arenites suggest exceptional floods carryi.g.debris from the far borders of the basin. Also, the immature sandstone composition has been interpreted as bei.g.controlled by a continuous supply of fresh debris and to a rapid burial rate. in addition, the disappearance of metaradiolarite(lydite AA) Paleozoic grains in the sandstone mineral suite could represent a distinctive marker of a progressive unroofi.g.of the Variscan chain and a clastic supply from deeper tectonic units.

关键词： Petrography Stratigraphy Provenance Molassic basins Sardinia