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Chinese Physics B 2009年第11期18卷 4912-4918页

作者：吴坚 h.d.summers School of Physics Beijing University of Aeronautics and Astronautics School of Physics and Astronomy Cardiff University

The intrinsic features involving a circularly symmetric beam profile with low divergence, planar geometry as well as the increasingly enhanced power of vertical-cavity surface-emitting lasers （VCSELs） have made the VCSEL a promising pump source in direct end bonding to a solid-state laser medium to form the minimized, on-wafer integrated laser system. This scheme will generate a surface contact pump configuration and thus additional end thermal coupling to the laser medium through the joint interface of both materials, apart from pump beam heating. This paper analytically models temperature distributions in both VCSEL and the laser medium from the end thermal coupling regarding surface contact pump configuration using a top-emitting VCSEL as the pump source for the first time. The analytical solutions are derived by introducing relative temperature and mean temperature expressions. The results show that the end contact heating by the VCSEL could lead to considerable temperature variations associated with thermal phase shift and thermal lensing in the laser medium. however, if the central temperature of the interface is increased by less than 20 K, the end contact heating does not have a significant thermal influence on the laser medium. In this case, the thermal effect should be dominated by pump beam heating. This work provides useful analytical results for further analysis of hybrid thermal effects on those lasers pumped by a direct VCSEL bond.

关键词： solid-state laser end pump thermal coupling vertical-cavity surface-emitting laser

An efficient approach to characterizing and calculating carrier loss due to heating and barrier height variation in vertical-cavity surface-emitting lasers

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Chinese Physics B 2010年第1期19卷 361-365页

作者：吴坚 h.d.summers School of Physics and Nuclear Energy Engineering Beijing University of Aeronautics and Astronautics School of Physics and Astronomy Cardiff University

It is important to determine quantitatively the internal carrier loss arising from heating and barrier height variation in a vertical-cavity surface-emitting quantum well laser （VCSEL）. however, it is generally difficult to realize this goal using purely theoretical formulas due to difficulty h, deriving the parameters relat^i~g to the quantum well structure. In this paper, we describe an efl：icient approach to characterizing and calculating the carrier loss due to the heating and the barrier height change in the VCSEL. In the method, the thermal carrier loss mechanism is combined with gain measurement and calculation. The carrier loss is re-characterized in a calculable form by constructing the threshold current and gain detuning-related loss current using the measured gain data and then substituting them for the quantum well-related parameters in the formula. The result can be expressed as a product of an exponential weight factor linked to the barrier height change and the difference between the threshold current and gain detuning-related loss current. The gain variation at cavity frequency due to thermal carrier loss and gain detuning processes is measured by using an AllnGaAs-AIGaAs VCSEL structure. This work provides a useful approach to analysing threshold and loss properties of the VCSEL, particularly, gain offset design for high temperature operation of VCSELs.

关键词： semiconductor laser vertical cavity surface emitting laser quantum well thermal carrier loss

From Imperfection to Perfection: Advanced 3d Facial Reconstruction Using MICA Models and Self-Supervision Learning

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Computer Modeling in Engineering & Sciences 2025年第2期142卷 1459-1479页

作者： Thinh d.Le duong Q.Nguyen Phuong d.Nguyen h.Nguyen-Xuan CIRTECh Institute HUTECH UniversityHo Chi Minh City72308Viet Nam

Research on reconstructing imperfect faces is a challenging *** this study,we explore a data-driven approach using a pre-trained MICA(MetrIC fAce)model combined with 3d printing to address this *** propose a training strategy that utilizes the pre-trained MICA model and self-supervised learning techniques to improve accuracy and reduce the time needed for 3d facial structure *** results demonstrate high accuracy,evaluated by the geometric loss function and various statistical *** showcase the effectiveness of the approach,we used 3d printing to create a model that covers facial *** findings indicate that our method produces a model that fits well and achieves comprehensive 3d facial *** technique has the potential to aid doctors in treating patients with facial injuries.

关键词： 3d face reconstruction self-supervised learning face defect 3d printed prototypes

dietary supplementation of valine,isoleucine,and tryptophan may overcome the negative effects of excess leucine in diets for weanling pigs containing corn fermented protein

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Journal of Animal Science and Biotechnology 2025年第1期16卷 267-281页

作者： Andrea P.Mallea Charmaine d.Espinosa Su A Lee Minoy A.Cristobal Leidy J.Torrez‑Mendoza hans h.Stein division of Nutritional Sciences University of IllinoisUrbanaIL 61801USA department of Animal Sciences University of IllinoisUrbanaIL 61801USA Present Address:EnviroFlight RaleighNCUSA.

Background diets with high inclusion of corn co-products such as corn fermented protein(CFP)may contain excess Leu,which has a negative impact on feed intake and growth performance of pigs due to increased catabolism of Val and Ile and reduced availability of Trp in the brain for serotonin ***,we hypothesized that the negative effect of using CFP in diets for weanling pigs may be overcome if diets are fortified with crystalline sources of Val,Trp,and(or)*** Three hundred and twenty weanling pigs were randomly allotted to one of 10 dietary treatments in a com-pletely randomized design,with 4 pigs per pen and 8 replicate pens per treatment.A corn-soybean meal diet and 2 basal diets based on corn and 10%CFP or corn and 20%CFP were *** additional diets were formu-lated by fortifying the basal diet with 20%CFP with Ile,Trp,Val,Ile and Val,Ile and Trp,Trp and Val,or Ile,Trp and Val.A two-phase feeding program was used,with d 1 to 14 being phase 1 and d 15 to 28 being phase *** scores were recorded every other *** samples were collected on d 14 and 28 from one pig per *** d 14,fecal samples were collected from one pig per pen in 3 of the 10 treatments to determine volatile fatty acids,ammonium concen-tration,and microbial *** pigs were also euthanized and ileal tissue was *** There were no effects of dietary treatments on any of the parameters evaluated in phase *** of 10%or 20%CFP in diets reduced(Pdy weight on d 28,and average daily gain(AdG)and average daily feed intake(AdFI)in phase 2 and for the entire experimental ***,pigs fed the CFP diet supplemented with Val,Ile,and Trp had final body weight,AdFI,AdG and gain to feed ratio in phase 2 and for the entire experiment that was not different from pigs fed the control *** scores in phase 2 were reduced(Pd protein may be included by up to 20%in diets for weanling pi

关键词： Branched-chain amino acids Corn fermented protein Leucine Tryptophan Valine Weanling pigs

dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： h.hOSSEINI O.BALILAShAKI department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3d) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

关键词： cylindrical cavity O353.4 point source porous medium stress concentration wave-field transformation

Tailored design of novel Co0-Coδ+dual phase nanoparticles for selective CO2 hydrogenation to ethanol

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Journal of Environmental Sciences 2025年第3期149卷 598-615页

作者： Subhasis das Ganapati d.Yadav department of Chemical Engineering Institute of Chemical TechnologyNathalal Parekh MargMatunga 400019MumbaiIndia

Catalytic hydrogenation of CO_(2)to ethanol is a promising solution to address the greenhouse gas(GhG)emissions,but many current catalysts face efficiency and cost *** based catalysts are frequently examined due to their abundance,cost-efficiency,and effectiveness in the reaction,where managing the Co^(0)to Co^(δ+)ratio is *** this study,we adjusted support nature(Al_(2)O_(3),MgO-MgAl_(2)O_(4),and MgO)and reduction conditions to optimize this balance of Co^(0)to Co^(δ+)sites on the catalyst surface,enhancing ethanol *** selectivity of ethanol reached 17.9%in a continuous flow fixed bed micro-reactor over 20 mol%Co@MgO-MgAl_(2)O_(4)(CoMgAl)catalyst at 270°C and 3.0 MPa,when reduced at 400°C for 8 *** results coupled with activity analysis confirmed that mild reduction condition(400°C,10%h_(2)balance N_(2),8 h)with intermediate metal support interaction favoured the generation of partially reduced Co sites(Co^(δ+)and Co^(0)sites in single atom)over MgO-MgAl_(2)O_(4)surface,which promoted ethanol synthesis by coupling of dissociative(Chx^(∗))/non-dissociative(ChxO^(∗))intermediates,as confirmed by density functional theory ***,the CoMgAl,affordably prepared through the coprecipitation method,offers a potential alternative for CO_(2)hydrogenation to yield valuable chemicals.

关键词： CO_(2)hydrogenation Ethanol Co-based catalysts Metal support ineraction dFT analysis

Neuroinflammation as a therapeutic target in huntington's disease

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Neural Regeneration Research 2025年第3期20卷 817-818页

作者： Andrea Kwakowsky Thulani h.Palpagama Center for Brain Research and department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George huntington presented his essay “On Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. huntington's disease(hd) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

关键词： huntington inflammation Medicine

Glial response in the midcingulate cortex in huntington’s disease

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Neural Regeneration Research 2025年第1期20卷 207-208页

作者： Thulani h.Palpagama Andrea Kwakowsky Center for Brain Research and department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

huntington’s disease(hd)is a genetic disease characterized by the progressive degeneration of the striatum and *** can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive *** causal mutation underlying hd results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

关键词： huntington degeneration cortex

Two texture zeros for dirac neutrinos in a diagonal charged lepton basis

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Chinese Physics C 2025年第1期49卷 127-138页

作者： Yessica Lenis John d.Gómez William A.Ponce Richard h.Benavides Instituto de Física Universidad de AntioquiaA.A.1226MedellínColombia Instituto Tecnológico Metropolitano Facultad de Ciencias Exactas y AplicadasCalle 73 N°76-354 via el voladorMedellínColombia

A systematic study of the neutrino mass matrix M_(v) with two texture zeros in a basis that the charged leptons are diagonal,and under the assumption that neutrinos are dirac particles is *** study is conducted without any approximation,first analytically and then *** neutrino oscillation data is used in our *** implications of M_(v) on lepton CP violation and neutrino mass spectrum are explored.

关键词： neutrinos texture zeros dirac particles

Valorization of Ubiquitous Plant Species Used as Food Packaging in Benin: A Sustainable Solution to Improve Quality of Life and Protect the Environment

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American Journal of Plant Sciences 2025年第1期16卷 51-63页

作者： Joli Prince Mintognissè Fossou Yann Christie Sissinto Adjovi Ulrich hilarion Ahéhéhinnou Frida Tovo Sèna Emmanuelle dédéhou Laboratory of Biochemistry and Molecular Biology of Centre Bninois de la Recherche Scientifique et de lInnovation Cotonou Benin National Agricultural University Ketou Benin Ecole des Sciences et Techniques de Conservation et de Transformation des Produits Agricoles Universit Nationale dAgriculture (ESTCTPA/UNA) Porto-Novo Benin

Vegetal leaves play a significant role in the daily lives of populations in developing countries. This study aimed to highlight the plant species used as food packaging in southern Benin. A survey questionnaire was administered in local markets, and informed consent was obtained from native guides. data were processed using Google Forms, and a phytochemical screening was conducted on the sampled species. A total of 311 individuals, including elders, vendors, and consumers, participated in the survey. The most commonly used plant species identified were Tectona grandis, Thalia geniculata, Musa sapientum, Gmelina arborea, Manihot esculenta, and Terminalia catappa. Several reasons, primarily cultural, explain the preference for these species. Notably, Tectona grandis and Musa sapientum demonstrated superior morphological, physical, and organoleptic qualities, measuring 79 cm by 53.5 cm and over 2 m by 50 cm, respectively. They accounted for 33.33% and 32.35% of usage. Additionally, fermented corn paste, making up over 53% of offerings, was the most popular food item. The mechanical properties of these leaves, such as flexibility, toughness, and relative impermeability, along with identified phytochemicals like terpenes, alkaloids, gallic acid, flavonoids, and coumarins, enhance food preservation and limit microbial activity. Promoting the use of these natural packaging materials over plastic alternatives could significantly reduce environmental pollution and mitigate the risks associated with toxic microorganisms in food, contributing to both ecological health and food safety.

关键词： Socio-Ethnobotanical Surveys Food Items Secondary Metabolites Bioactive Natural Substances Phytochemical Screening