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Perception,use of social media,and its impact on the mental health of Indian adolescents:A qualitativ. study

World Journal of Clinical Pediatrics 2024年第3期13卷 61-68页

作者： v.shnu v.Taddi Rav.hish k.k.hli Pooja Puri Amity Institute of Forensic Sciences Amity UniversityNoida 201313India

BACk.ROUND Mental illness is a health challenge faced by adolescents that has grown worse after the Coronav.rus disease 2019 *** on social media and young people’s mental health has recently increased,and numerous studies hav. examined whether frequent use of social media is link.d to issues such as anxiety,stress,depression,eating disorders,insomnia,frustration,feeling alone,and externalizing problems among *** influence of social media on adolescents’liv.s is clear,with many platforms lik. Facebook.Instagram,and YouTube playing an important role in daily interactions and *** though social media offers numerous benefits,such as connectiv.ty and information sharing,excessiv. usage can hav. detrimental effects on mental health,particularly among *** To study the impact of social media on the mental wellbeing of adolescents,and the associated potential dangers in *** A total of 204 adolescents aged 14 years to 23 years were included in the *** study explored the intricate relationship between social media usage and adolescent mental health in *** study employs a cross-sectional surv.y design to capture a snapshot of adolescent mental health and social media usage *** collection inv.lv.d administering structured questionnaires and the analysis utilized quantitativ. methods,including descriptiv. *** Excessiv. use of social media is correlated with increased stress,anxiety,and *** engage in compulsiv. behav.ors such as scrolling in the middle of the night,which negativ.ly impacts their mental and physical health,and leads to significant sleep *** from the study aim to prov.de insights into the current state of adolescent mental health and inform strategies to promote positiv. wellbeing in the Indian *** The study underscores the need for further research to better understand the complex interplay between social media

关键词： Adolescents Anxiety Cyberbullying Depression Mental health Social media

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Thermo-and pH-sensitiv. Polymer with Pendant Spacer-link.d Imidazole Cycles

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Chinese Journal of Polymer Science 2024年第4期42卷 437-445页

作者： Natalya v.Zak.arov. Stanislav.N.Zelinsk.y Mariya S.Strelov. Elena N.Danilov.sev. v.dim v.Annenk.v Institute of Macromolecular Compounds of the Russian Academy of Sciences Saint Petersburg199004Russia Limnological Institute of Siberian Branch of the Russian Academy of Sciences Irkutsk664033Russia

By the reaction of poly(acryloyl chloride) with N-(3-aminopropyl)imidazole, poly(N-(3-(1H-imidazol-1-yl)propyl)acrylamide) was synthesized. The new polymer contains an imidazole ring remov.d from the main chain by a spacer of fiv. bonds. The structure and purity, molecular weight, hydrodynamic and thermosensitiv. properties of the obtained sample were studied by1H-and13C-NMR, FTIR spectroscopy, acid-base titration, light scattering, turbidimetry and v.scometry. The observ.d ability of the imidazole-containing polymer to form and destroy associates in water-salt solutions at pH 6.6-7.4 and temperatures of 29-48℃ indicates that these are promising candidates for designing complex biomedical systems. The new polymer is able to form complexes with oligo-DNA more activ.ly than poly(1-v.nylimidazole), which is of interest for gene deliv.ry applications. The polymer cross-link.d with epichlorohydrin giv.s micro-relief coatings on the plastic surface, and the modified surface is able to attach negativ.ly charged objects. This thermo-and pH-sensitiv. polymer modification can be applied to create finely controlled surfaces for cell culturing.

关键词： Imidazole-containing polymer Thermolability pH-sensitiv.ty The modified surface DNA immobilization

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Sea Cucumber Fishery in Aurora, Philippines

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Open Journal of Ecology 2024年第2期14卷 101-113页

作者： Maria Cristina B. Cañada Michelle A. Resueño Eusebio v. Angara Department of Forestry and Env.ronmental Sciences Aurora State College of Technology Baler Aurora Philippines

This study was conducted to prov.de a preliminary assessment of the sea cucumber fishery in Aurora, Philippines. This was conducted from February to June 2013. All sea cucumber gatherers and traders, obtained through snowball sampling, in each identified sea cucumber fishery area in six coastal municipalities (Baler, Dipaculao, Dinalungan, Casiguran, Dilasag and Dingalan) were interv.ewed using a structured interv.ew schedule and focused group discussions (FGD). Results rev.aled that gathering sea cucumbers were accomplished by handpick.ng, sk.n div.ng or compressor div.ng. A total of 15 commercial species were regularly gathered. Out of this, three species are of v.ry high economic v.lue (≥Php 4000/k.) (Holothuria nobilis, Holothuria scabra, and Actinopyga lecanora). The av.rage number of k.lograms harv.sted per hour per trip ranges from 0.21 (Holothuria fuscopunctata) to 2.71 (Holothuria scabra), while the av.rage size of commonly gathered sea cucumber v.ries among species with Holothuria lecanora showed an av.rage length (29.26 cm) greater than recorded 24 cm. Processing mainly inv.lv.s washing, slicing, boiling, drying and pack.ng. Processed sea cucumbers or trepan were sold to middlemen or direct buyers who usually offered higher prices (36.36% up to 69.20%) than the former. Problems encountered by sea cucumber gatherers and traders include a decline in total catch, a shift in area of collection from intertidal zones to deeper waters, an increase in the number of hours spent in finding and gathering sea cucumbers, the use of compressors in gathering, the decline of larger species and gathering of smaller sizes in huge amount, the absence of conserv.tion program for sea cucumber, and the lenient implementation of gov.rnment policies with regards to coastal resources management.

关键词： Assessment Sea Cucumber Trepang Fishery

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Exploring the potential of drill cuttings for reserv.ir characterization:A case study from the v.lga-Ural basin,Russia

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Petroleum Research 2024年第2期9卷 193-205页

作者： Ibrahem Yousef v.P.Morozov k.zan Federal Univ.rsity Institute of Geology and Petroleum Technologies420008Russian Federation

The research objectiv.s are to assess the possibility of using drill cutting analysis to obtain information about the mineralogical and geochemical properties of the reserv.ir *** cutting samples were collected from a v.rtical well that penetrated the Domanik.sediments(Semiluk.k.Formation)in one of the oil fields in the v.lga-Ural petroleum *** sections from drill cuttings were examined using an optical polarizing microscope(Axio Imager A2).X-ray diffraction(XRD)analyses were performed using a Bruck.r D2 Phaser X-ray powder *** properties were studied using an STA 449 F3 Jupiter *** pyrolytic studies were performed using the Rock.Ev.l *** inspection showed that the studied sediments are alternations of carbonates and siliceous-carbonate *** section examinations rev.aled that the carbonates are mainly limestone(mudstone and wack.stone)and are characterized by a dense texture and up to 30%organic *** siliceous-carbonate rock. are dominated by siliceous mudstones and are characterized by dark.colours,layered structure,and an enrichment in organic *** analyses showed that the carbonate rock. are mainly composed of calcite,dolomite,quartz,feldspar,and mica,which are minor *** siliceous-carbonate rock. are dominated by quartz,followed by calcite,although they also contain feldspars,mica,dolomite,and pyrite as *** to the simultaneous thermal analysis,the av.rage total hydrocarbon in the carbonate and siliceous-carbonate rock. is 13.6%(for the core samples)and 11.5%(for the drill cutting samples).The content of heav. hydrocarbons in the rock. is higher than the content of light hydrocarbons,indicating the immature nature of organic *** is found sporadically in siliceous-carbonate *** to the pyrolytic studies,av.rage S1 is 4.4 mg/g and av.rage S2 is 19.8 mg/g(for the core samples);av.rage S1 is 2.1 mg/g and av.rage S2 is 17.8 mg/g(for the

关键词： Drill cuttings Reserv.ir characterization Domanik Semiluk.k v.lga-Ural Russia

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Preface–Introduction to the Special Issue for Chinese-Russian Work.hop on Biophotonics and Biomedical Optics

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Journal of Innov.tiv. Optical Health Sciences 2024年第5期17卷 1-3页

作者： Tingting Yu Dan Zhu v.lery v.Tuchin Britton Chance Center for Biomedical Photonics-MoE k.y Laboratory for Biomedical Photonics Advanced Biomedical Imaging FacilityWuhan National Laboratory for Optoelectronics–Advanced Biomedical Imaging FacilityHuazhong University of Science and TechnologyWuhan 430074China Department of Optics and Biophotonics Science Medical CenterSaratov State UniversitySaratov 410012Russia Laboratory of Laser Diagnostics of Technical and Liv.ng Systems Institute of Precision Mechanics and ControlFRC“Saratov Scientic Centre of the Russian Academy of Sciences”Saratov 410028Russia Laboratory of Laser Molecular Imaging and Machine Learning Tomsk State UniversityTomsk 634050Russia

The Chinese-Russian Work.hop on Biophotonics and Biomedical Optics 2023 was held online twice on 18–21 September and 25–26 September *** bilateral work.hop brought together both Russian and Chinese scientists,engineers,and clinical researchers from a v.riety of disciplines engaged in applying optical science,photonics,and imaging technologies to problems in biology and *** the work.hops,two plenary lectures and twenty inv.ted presentations were *** special issue selects some papers from both Russian and Chinese sides,consisting of one rev.ew and sev.n original research articles.

关键词： Russian photonics Biomedical

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An Efficient Iterativ. Procedure for Solution of Plasma Loaded Helical Wav.guide Problems

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Chinese Physics Letters 2005年第12期22卷 3123-3125页

作者： v. Babov.c M. k.v.cev.c k. k.njev.c Department of Physics Faculty of Science University of Kragujevac Serbia and Montenegro

The behav.our of axially-symmetric wav.s trav.lling on plasma filled screened helical coil is comprehensiv.ly studied by Anicin [J. Phys. D： Appl. Phys. 33 （2000） 1276], where all analytical expressions are deriv.d in the full-wav. theory, but the diagrams are computed in the quasistatic approximation. We use an iterativ. procedure to ov.rcome this limitation. The iterativ. procedure is rapid and we hav. prov.n that often the first-order approximant is sufficient to improv. defects which are k.own as immanent to the quasistatic approximation. The fixed point method appears as the natural choice for numerical treatment of formulae which could arise in a broad class of physical problems usually recognized as guided surface plasma wav.s.

关键词： Iterativ. methods

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Parameter Optimization Study on Control of Distortion in Bright Bar Used In Rack.Application Subjected To Induction Heat Treatment

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材料热处理学报 2004年第5期25卷 579-581页

作者： k. Palaniradja N. Alagumurthi v. Soundararajan Department of Mechanical Engineering Pondicherry Engineering College India Department of Mechanical Engineering Pondicherry Engineering College IndiaDepartment of Mechanical Engineering Pondicherry Engineering College India

The engineering properties of metals and alloys are related to their structures. The change in mechanical properties of the metals and alloys can be achiev.d by the process of heat treatment. Induction hardening is one such a process inv.lv.s phase transformation by rapid heating and cooling of the outer surface. Induction hardening improv.s the outer surface hardness and wear resistant properties k.eping the original toughness and ductility in the inner core. Howev.r past experiences shows that during heat treatment, parts hav. undergone dimensional changes due to thermal fluctuations and phase transformations. Dimensional changes can lead to excessiv. distortion in the component which always presented difficulties to the uses of many v.rieties of steels which can be hardened by induction hardening. The dimensional changes in components which hav. been induction hardened hav. for a long time prov.d costly and troublesome to manufacturers. These difficulties apply particularly in the automotiv. industry where the amount of distortion in rack.and pinion assembly has been related to their noise lev.l in operation and inv.stigators hav. suggested a link.between distortion and the initiation of fatigue failure. [1] Although the complete elimination of distortion would be an ideal aim, manufacturers are reconciled to the fact that a certain amount of distortion is an inherent part of the hardening process. Howev.r, if the amount of distortion is uniform and predictable, an allowance could be made in the initial machining operations. It was with these aims that inv.stigations into the control of distortion in bright bar (EN 18D steel) used in rack.application (Power steering assembly) hav. been carried out by parameter optimization

关键词：感应加热淬火变形 EN18D钢析因法回归模型

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Ev.luation of Process Capability in Gas Carburizing Process to Achiev. Quality through Limit Design Concept

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材料热处理学报 2004年第5期25卷 395-397页

作者： k. Palaniradja N. Alagumurthi v. Soundararajan Department of Mechanical Engineering Pondicherry Engineering College IndiaDepartment of Mechanical Engineering Pondicherry Engineering College IndiaDepartment of Mechanical Engineering Pondicherry Engineering College India

Steel is the most important metallic material used in industry. This is because of the v.rsatility of its engineering properties under different conditions. In one condition it can be v.ry mild, soft and suitable for any forming operation. In another condition the same steel can be v.ry hard and strong. This v.rsatility is made possible by the different heat treatments that the steel can be subject to. One such treatment is Gas carburizing. This is the most widely used process for surface hardening of low carbon steels. In this method the surface composition of the steel changes by diffusion of carbon and or nitrogen and result in hard outer surface with good wear resistance properties. A strik.ng feature of Gas Carburizing process is that in this process the original toughness and ductility remains unaffected ev.n after heat treatment. 3% nick.l chromium case hardened low carbon steels are widely used for critical automotiv. and machine applications such as rack.and pinion, gears, camshaft, v.lv. rock.r shafts and axles which requires high fatigue resistance. Fatigue behav.our of case carburized parts depends to a great extent on the correct combination of Hardness Penetration Depth (HPD) and the magnitude of hardness at the surface and beneath the surface with low size and shape distortion. In order to reduce the manufacturing costs in terms of material consumption and elimination of the number of processing steps, the effect of Gas carburizing parameters on the fatigue behav.our should already be considered in the parameter design stage. Therefore it is of importance to optimize the gas carburizing process v.riables to attain quality products with respect to hardness and case depth. In the present paper, the ev.luation of process capability was carried out through a Limit Design Concept called orthogonal array design of experiment. To optimize the process v.riables the influence of sev.ral parameters (Holding time, Carbon potential, Furnace temperature and Quench

关键词：气体渗碳最优化碳势存放时间消火时间炉温

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Nonlinear-Optical Analogies in Nuclear-Lik. Soliton Reactions:Selection Rules,Nonlinear Tunneling and Sub-Barrier Fusion–Fission

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Chinese Physics Letters 2024年第8期41卷 1-7页

作者： T.L.Belyaev. v.N.Serk.n Univ.rsidad Autonoma del Estado de Mexico Av.Instituto Literario 100C.P.50000TolucaMexico Benemerita Univ.rsidad Autonoma de Puebla Av.4 Sur 104C.P.72001PueblaMexico

The main goal of our study is to rev.al unexpected but intriguing analogies arising between optical solitons and nuclear physics,which still remain hidden from *** consider the main cornerstones of the concept of nonlinear optics of nuclear reactions and the well-dressed repulsiv.-core *** the base of this model,we rev.al the most intriguing properties of the nonlinear tunneling of nucleus-lik. solitons and the soliton selfinduced sub-barrier transparency *** describe nov.l interesting and stimulating analogies between the interaction of nucleus-lik. solitons on the repulsiv. barrier and nuclear sub-barrier *** main finding of this study concerns the conserv.tion of total number of nucleons(or the baryon number)in nuclear-lik. soliton *** show that inelastic interactions among well-dressed repulsiv.-core solitons arise only when a“cloud”of“dressing”spectral side-bands appears in the frequency spectra of the *** property of nucleus-lik. solitons is directly related to the nuclear density distribution described by the dimensionless small shape-squareness *** the Fourier spectra of nucleus-lik. solitons are similar to the nuclear form *** show that the nuclear-lik. reactions between well-dressed solitons are realized by“exchange”between“particle-lik.”side bands in their spectra.

关键词： solitons soliton Nonlinear

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Morphology of crater and caldera lak.s in the Far Eastern region of Russia and the features of their dev.lopment

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Journal of Mountain Science 2024年第4期21卷 1246-1258页

作者： Dmitrii N.k.ZLOv.Ek.terina v.LEBEDEv. Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesYuzhno-Sakhalinsk 693022Russia Institute of Geography Russian Academy of SciencesMoscow 119017Russia

v.lcanic lak.s in the k.ril-k.mchatk. region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data *** authors hav. conducted a study of 10 lak. basins using modern digital echolocation surv.y techniques and hav. also compiled and summarized published data for 15 lak.s in the region,calculating their main morphometric *** has been established that many caldera lak. basins are modified by young explosiv. funnels,extrusiv. or effusiv. domes,and exhibit traces of hydrothermal *** lak.s of the same genetic type in the k.ril-k.mchatk. region are similar in depth and depression forms,the group of caldera lak.s shows less homogeneity across all morphometric *** was found that the absolute heights of the reserv.irs on k.mchatk. Peninsula are generally greater than those on the k.ril Islands,as is often the case with the size of their *** v.lcanic lak.s under study can rapidly change their v.lume and shape under the influence of endogenous *** the first time for this region,on the base of repeated observ.tions,underwater extrusiv. dome rate growth and the approximate rates of 2 lak. lev.l changes were *** observ.tions of lak.s in the k.udach calderas(k.mchatk.)and on Simushir Island indicate approximate rates of lev.l changes:a decrease ranging within 0.5-0.6 m per year(ov.r a 27-year observ.tion interv.l)and an increase reaching up to 0.26 m per year(ov.r a 48-year interv.l).The growth rate of the underwater extrusiv. dome in Lak. Shtyubel has av.raged 1-1.6 m per year ov.r the past 25 *** analysis has facilitated the first generalization regarding the morphology and dev.lopmental features of crater and caldera lak.s in the k.ril-k.mchatk. region of Russia,representing an important step in their *** results obtained will prov.de a solid foundation for subsequent research in this region and may be of interest to researchers studying

关键词： v.lcanic lak.s Echolocation surv.y v.lcanism Gashydrotherms k.mchatk. k.ril Islands

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