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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,concerning galactic and intergalactic interstellar gas. Highlights for me included my work on the orbiting telescope Copernicus, including the discovery of interstellar deuterium;early observations of absorption associated with fivetimes ionized oxygen;and discoveries concerning 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 using 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 being 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

Comparative study of thulium fiber laser versus holmium:yttrium-aluminum-garnet laser for ureteric stone management with semi-rigid ureteroscopy: A prospective, single-center study

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Asian Journal of Urology 2024年第3期11卷 460-465页

作者： Ankit gupta Arvind P.ganpule Ankush Puri Abhishek g.Singh ravindra B.Sabnis Mahesh r.Desai Muljibhai Patel Urological Hospital NadiadGujaratIndia

Objective:To compare the efficacy and safety of thulium fiber laser(TFL)and holmium:yttrium-aluminum-garnet(Ho:YAg)laser for ureteric stone management with semi-rigid ***:In a prospective study from January 2020 to December 2021,we compared 40 patients in each group who underwent semi-rigid ureteroscopic lithotripsy with TFL and that with Ho:YAg *** volume,stone density,stone fragmentation rates,total lasing time,total operative time,endoscopic vision,retropulsion and stone free rates were analyzed in both groups and ***:Mean stone volume was comparable in the TFL group and the Ho:YAg laser group(282.45[standard deviation,SD 139.79]mm3 vs.279.49[SD 312.52]mm3;p=0.964).Mean stone density was also comparable in the TFL group and the Ho:YAg laser group(1135.30[SD 317.04]Hounsfield unit vs.1131.75[SD 283.03]Hounsfield unit;p=0.959).The mean stone fragmentation rates calculated as stone volume divided by lasing time were 25.85(SD 10.61)mm3/min and 21.37(SD 14.13)mm3/min in the TFL group and the Ho:YAg laser group,respectively(p=0.113).The mean total lasing time(10.15[SD]4.69 min vs.11.43[SD 4.56]min;p=0.222),mean operative time(25.13[SD 9.51]min vs.25.54[SD 10.32]min;p=0.866),and mean total hospital stay(2.62[SD 0.77]days vs.2.61[SD 0.84]days;p=0.893)were comparable in the TFL group and in the Ho:YAg *** vision was better and retropulsion was less in the TFL *** stone-free rate at 1 month postoperatively was slightly better in the TFL group(100%vs.90%;p=0.095).

关键词： Laser Stone Urolithiasis Thulium Holmium

Autoantibodies against beta cells to predict early insulin requirements in pediatric patients with clinically diagnosed type 2 diabetes

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World Journal of Diabetes 2024年第8期15卷 1717-1725页

作者： Jorge M Molina Patricia g Medina rita A gomez Julia r Herrera Nancy L Martínez Brenda Hernández Yesenia garcía Department of Endocrinology Children’s Hospital Federico GomezMexico 06720Mexico National Medical Center"Siglo XXI" UMAE Hosp EspecialidadesUnidad Invest Med Epidemiol ClinMexican Social Security InstituteMexico 06720Mexico research Division UMAE Hospital de EspecialidadesCentro Médico Nacional Siglo XXIMexican Institute of Social SecurityMexico 06720Mexico Epidemiology research Unit in Endocrinology and Nutrition Federico Gómez Children’s HospitalMexico 06720Mexico Department of Endocrinology Comprehensive Health Unit for Trans PersonsMexico 11340Mexico

BACKgrOUND Autoimmunity has emerged as a probable disease modifier in patients with clinically diagnosed type 2 diabetes mellitus(T2DM),that is,patients who have insulin resistance,obesity,and other cardiovascular risk factors,suggesting that the presence of glutamic acid decarboxylase(anti-gAD65),islet antigen 2(anti-IA2),and zinc transporter 8(anti-Zn8T)antibodies could have deleterious effects on beta cell function,causing failure and earlier requirement for insulin *** To evaluate anti-gAD65,anti-IA2 and anti-Zn8T as predictors of early insulin requirement in adolescents with a clinical diagnosis of *** This was a case–control study in patients with clinically diagnosed with T2DM(68 cases and 64 controls with and without early insulin dependence respectively),male and female,aged 12–18 ***,blood pressure,glucose,insulin,C-peptide,glycated hemoglobin A1c,and lipid profiles were *** was used to measure anti-gAD65,anti-IA2,and anti-Zn8T *** statistics,Pearson'sχ2 test,Student's t test,and logistic regression was performed.Pred statistically *** There were 132 patients(53.8%female),with a mean age was 15.9±1.3 years,and there was a disease evolution time of 4.49±0.88 *** presence of anti-gAD65,anti-IA2,and anti-Zn8T positivity was found in 29.5%,18.2%,and 15.9%,*** the groups by early or no insulin dependence showed that the group with insulin had a higher frequency of antibody positivity:anti-gAD65 odds ratio(Or):2.42(1.112–5.303,P=0.026);anti-IA2:Or:1.55(0.859–2.818,P=0.105);and anti-Zn8T:Or:7.32(2.039–26.279,P=0.002).CONCLUSION Anti-gAD65 positivity was high in our ***-gAD65 and anti-Zn8T positivity showed a significantly depleted beta cell reserve phenotype,leading to an increased risk of early insulin dependence.

关键词： Diabetes Obesity Adolescents Autoimmunity Beta cell Insulin requirements

Investigating the impact of the universal function of the nuclear proximity potential in heavy-ion fusion cross sections

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Communications in Theoretical Physics 2024年第5期76卷 86-93页

作者： r gharaei E Sarvari Department of Physics Sciences FacultyHakim Sabzevari UniversityPO Box 397SabzevarIran Department of Physics Faculty of ScienceFerdowsi University of MashhadPO Box 91775-1436MashhadIran Science Faculty Department of PhysicsTarbiat Modares UniversityTehranIran

The fusion barriers and cross sections of 15 colliding systems with 320≤Z_(1)Z_(2)≤1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion *** realize this goal,we select three versions of the phenomenological proximity potentials,including Prox.77,Zhang 2013,and guo 2013,to calculate the nucleus-nucleus *** experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations,including couplings to the low-lying 2^(+)and 3^(-)states in the target and *** calculated results show that the universal functions of the guo 2013 and Prox.77 models provide the lowest and highest fusion barriers,*** addition,it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy *** highest sensitivity to the mass number of the projectile belongs to the results of Prox.77.A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping *** results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 *** the heavier systems,the results of the guo 2013 model at sub-barrier energies provide a good description of the available data.

关键词： fusion reactions proximity-type potentials universal function coupled-channel calculations

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 lasting *** science,this can be especially problematic,because our lack of understanding 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-coding regions,EVs are far more than just cellular *** fact,EVs are emerging 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

Interpreting 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 Ingegneria 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 widening and the dismantling and reworking of the coeval volcanic activity. The sandstone composition clearly changes from quartzolithic to feldspatholithic upwards, as a response to the same change of feeding and reworking of the volcanic rocks. Occasionally, interbedded quartzolithic arenites suggest exceptional floods carrying debris from the far borders of the basin. Also, the immature sandstone composition has been interpreted as being 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 unroofing of the Variscan chain and a clastic supply from deeper tectonic units.

关键词： Petrography Stratigraphy Provenance Molassic basins Sardinia

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

During 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 promoting inflammatory processes and immune cell infiltration in different organs and systems while impacting metabolic function by altering lipolysis, mitochondrial activity, and insulin sensitivity. In dairy cows, endotoxins enter the bloodstream after overcoming the defense mechanisms of the epithelial barriers, particularly during 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, leading to the release of free fatty acids into the bloodstream. When excessive and protracted, endotoxin-induced lipolysis can impair adipocyte's insulin signaling 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, highlighting the gaps in our knowledge of the mechanisms underlying 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

Pile foundation in alternate layered liquefiable and non-liquefiable soil deposits subjected to earthquake loading

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 359-376页

作者： Praveen Huded M Suresh r Dash LEA Associates South East Asia Pvt.Ltd. New Delhi 110044India Indian Institute of Technology Bhubaneswar Khurda 752050India

Pile foundations are still the preferred foundation system for high-rise structures in earthquake-prone *** foundations have experienced failures in past earthquakes due to *** on pile foundations in liquefiable soils has primarily focused on the pile foundation behavior in two or three-layered soil ***,in natural occurrence,it may occur in alternative layers of liquefiable and non-liquefiable ***,the experimental and/or numerical studies on the layered effect on pile foundations have not been widely addressed in the *** of the design codes across the world do not explicitly mention the effect of sandwiched non-liquefiable soil layers on the pile *** the present study,the behavior of an end-bearing pile in layered liquefiable and non-liquefiable soil deposit is studied *** study found that the kinematic bending moment is higher and governs the design when the effect of the sandwiched non-liquefied layer is considered in the analysis as opposed to when its effect is ***,ignoring the effect of the sandwiched non-liquefied layer in a liquefiable soil deposit might be a nonconservative design approach.

关键词： pile foundation liquefaction alternately layered soil fixity effect layered effect

Empirical Wavelet Transform Based Method for Identification and Analysis of Sub-synchronous Oscillation Modes Using PMU Data

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 34-40页

作者： Joice g.Philip Jaesung Jung Ahmet Onen the Department of Energy Systems research Ajou UniversitySuwonSouth Korea the Department of Electrical and Electronic Engineering Abdullah Gul UniversityKayseri38080Turkey the Department of Electrical and Computer Engineering College of EngineeringSultan Qaboos UniversityAl-KhoudMuscatOman

This paper proposes an empirical wavelet transform(EWT)based method for identification and analysis of sub-synchronous oscillation(SSO)modes in the power system using phasor measurement unit(PMU)*** phasors from PMUs are preprocessed to check for the presence of *** the presence is established,the signal is decomposed using EWT and the parameters of the mono-components are estimated through Yoshida *** superiority of the proposed method is tested using test signals with known parameters and simulated using actual SSO signals from the Hami Power grid in Northwest *** show the effectiveness of the proposed EWT-Yoshida method in detecting the SSO and estimating its parameters.

关键词： Empirical wavelet transform(EWT) sub-synchronous oscillation Prony-based method Yoshida algorithm variational mode decomposition phasor measurement unit(PMU)