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Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola M.Johannessen Tor i.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. in general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic Minimum ice Climate

Coarse to Fine: The Role of Severe Plastic Deformation in Advancing Titanium-Based Medical implants - A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana R Mihajlović Bojan i Međo ivana Lj Cvijović-Alagić Veljko R Djokić Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča institute of Nuclear Sci-ences-National institute of the Republic of Serbia University of Belgrade11001BeogradSerbia innovation Centre of the Faculty of Technology and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(SPD)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the SPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPD techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the SPD process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties

Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review

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Neural Regeneration Research 2025年第1期20卷 82-92页

作者： Stiven Roytman Rebecca Paalanen Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico i.Bohnen Department of Radiology University of MichiganAnn ArborMIUSA Department of Neurology University of MichiganAnn ArborMIUSA Morris K.Udall Center of Excellence for Parkinson’s Disease Research University of MichiganAnn ArborMIUSA institute for Kinesiology Research Science and Research Centre KoperKoperSlovenia Department of Health Sciences Alma Mater Europaea–ECMMariborSlovenia Parkinson’s Foundation Research Center of Excellence University of MichiganAnn ArborMIUSA Department of Neurology University of GroningenUniversity Medical Center GroningenGroningenThe Netherlands Neurology Service and GRECC VA Ann Arbor Healthcare SystemAnn ArborMIUSA

Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging *** and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous *** effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory *** mechanisms which underpin the integration of these multisensory signals are the principal topic of the present *** multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older *** emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and *** the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s *** also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older ***,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases.

关键词： aging balance encephalography functional magnetic resonance imaging gait multisensory integration Parkinson’s disease positron emission tomography somatosensory vestibular visual

Nano-Enhanced Dairy Scum Biodiesel Blends:Unleashing the Power of Aluminium Oxide for Sustainable and Efficient Engine Performance

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Journal of Thermal Science 2025年第1期34卷 283-302页

作者： Veeranna MODi Prasad B.RAMPURE Sunil Kumar SHETTY Madeva NAGARAL Channa Keshava NAiK N Johar MGM Muhammad irsyad ABDULLAH Abdullah i.AL-MANSOUR Shamshad ALAM KLE College of Engineering and Technology ChikodiVisvesvaraya Technological University Nitte (Deemed to be University) NMAM Institute of Technology (NMAMIT)Department of Mechanical Engineering Aircraft Research and Design Centre HAL Department of Mechanical Engineering BGS College of Engineering and TechnologyBengaluruAffiliated to Visvesvaraya Technological University Management and Science University Department of Civil Engineering College of EngineeringKing Saud University

This study investigates the effect of aluminium oxide nanoparticlesaddition to biodiesel blends made from dairy milk scum on performance and combustion characteristics of the diesel *** dispersion of Al2O3nanoparticles in B20 blends at different concentrations was done with the help of *** number of blends were prepared for the *** Machine learning algorithms(Random Forest（RF）and CatBoost) was used for the *** results show that in comparison to biodiesel blends without nanoparticles,the kinematic viscosity and density is higher for fuel blends with *** these Fuel blends have higher calorific *** blends exhibited reduced Brake Specific Fuel Consumption（BSFC） of2.85% than the blends without nano particles(Dairy Scum Methyl Ester Biodiesel 20%+Neat Diesel 80%（in volume）,DSMEB20),57.14% less CO,40.8% less hydrocarbon,and increased NOxemissions compared to conventional diesel,contributing to the development of environmentally friendly and renewable biofuel blends with *** B20NP30 is the optimal blend for performance and emission *** study concludes with findings on enhanced Brake Thermal Efficiency（BTE） of 26.29% in 3×10-5（in volume） Al2O3nanoparticle-blended DSME B20 and other DSME B20 fuel blends,emphasizing the importance of optimal nanoparticle *** correlation matrix shows how engine load,efficiency measures（BTE,BSFC）,and emissions（CO,CO2,NOx,Smoke） are connected in complex *** results help us understand the complicated dynamics of engine performance and emission characteristics ***'s diagram for BTE and BSFC shows that CatBoost-based BTE models perform superior to RF-based models during the training as well as testing *** results were obtained for CO and CO2emission results.

关键词： Al2O3 concentration Ci engine Dairy Scum Methyl Ester Biodiesel

Prognostic impact of inflammatory and nutritional biomarkers in pancreatic cancer

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World Journal of Clinical Oncology 2025年第1期16卷 5-9页

作者： Macarena Teja María i Garrido Abrahams Ocanto Felipe Counago Department of Radiation Oncology GenesisCare-San Francisco de Asís University HospitalMadrid 28002Spain Department of Radiation Oncology GenesisCare-Vithas La Milagrosa University HospitalMadrid 28010Spain National Director GenesisCare SpainMadrid 28043Spain Department of Medicine School of MedicineHealth and SportEuropean University of MadridMadrid 28670Spain

Pancreatic cancer is usually associated with a poor *** is the main curative treatment but pancreatic operations are aggressive and new tools that help clinicians to predict surgical and prognostic outcomes are *** et al recently published a retrospective,single centre cohort study evaluating the impact of seven nutritional and inflammatory markers in pancreatic cancer surgical patients:The albumin-to-globulin ratio,prognostic nutritional index(PNi),systemic immune-inflammation index(Sii),neutrophil-to-lymphocyte ratio(NLR),platelet-to-lymphocyte ratio(PLR),nutritional risk index,and the geriatric nutritional risk index.A significant correlation was found between the PNi,Sii,NLR,and PLR and a hospital discharge of less than 15 *** a univariable analysis,PNi,Sii,NLR and PLR were significantly related to recurrence-free survival and,in a multivariable analysis PNi was associated with overall *** meta-analyses corroborate the results in terms of prognosis but individual studies are discordant on their ***,the cut-off values for these markers vary significantly between studies and there are no clinical trials comparing them to identify the most relevant *** are limitations when implementing nutritional and inflammatory biomarkers into clinical practice and further studies are needed in order to answer these questions.

关键词： inflammatory biomarkers Nutritional biomarkers Pancreatic cancer Prognosis Surgical complications

The effect of rotation on plane waves in generalized thermo-microstretch elastic solid with one relaxation time for a mode-i crack problem

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Chinese Physics B 2011年第7期20卷 266-278页

作者： Kh.Lotfy Mohamed i.A.Othman Department of Mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt Department of Mathematics Faculty of SciencealmithnabQassim UniversityP.O.Box 6666AlmithnabKingdom of Saudi Arabia

The present paper is aimed at studying the effect of rotation on the general model of the equations of the generalized thermo-microstretch for a homogeneous isotropic elastic half-space solid, whose surface is subjected to a Mode-i crack problem. The problem is studied in the context of the generalized thermoelasticity Lord Shulman＇s （L-S） theory with one relaxation time, as well as with the classical dynamical coupled theory （CD）. The normal mode analysis is used to obtain the exact expressions for the displacement components, the force stresses, the temperature, the couple stresses and the microstress distribution. The variations of the considered variables through the horizontal distance are illustrated graphically. Comparisons of the results are made between the two theories with and without the rotation and the microstretch constants.

关键词： Lord-Shulman's theory thermoelasticity microrotation microstretch

Bianchi type i in f(T) gravitational theories

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Chinese Physics B 2016年第5期25卷 58-64页

作者： M i Wanas G G L Nashed O A ibrahim Astronomy Department Faculty of Science Cairo University Cairo Egypt Centre for Theoretical Physics The British University in Egypt El-Sherouk City Egypt Mathematics Department Faculty of Science Ain Shams University Cairo Egypt Egyptian Relativity Group (ERG) Giza Egypt

A tetrad field that is homogeneous and anisotropic which contains two unknown functions A（t） and B（t） of cosmic time is applied to the field equations of f（T）, where T is the torsion scalar, T = T~μ_（νρ）S_μ^（νρ）. We calculate the equation of continuity and rewrite it as a product of two brackets, the first is a function of f（T） and the second is a function of the two unknowns A（t） and B（t）. We use two different relations between the two unknown functions A（t） and B（t） in the second bracket to solve it. Both of these relations give constant scalar torsion and solutions coincide with the de Sitter one. So,another assumption related to the contents of the matter fields is postulated. This assumption enables us to drive a solution with a non-constant value of the scalar torsion and a form of f（T） which represents ΛCDM.

关键词： f(T) gravitational theory Bianchi type i special solutions

Hybridization and genome evolution i： The role of contingency during hybrid speciation

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Current Zoology 2013年第5期59卷 667-674页

作者： Fabrice EROUKHMANOFF Richard i. BAiLEY Glenn-PETER SaeTRE Centre for Ecological and Evolutionary Synthesis (CEES) Department of Biology University of Oslo Norway

Homoploid hybrid speciation （HHS） involves the recombination of two differentiated genomes into a novel, func- tional one without a change in chromosome number. Theoretically, there are numerous ways for two parental genomes to recom- bine. Hence, chance may play a large role in the formation of a hybrid species. if these genome combinations can evolve rapidly following hybridization and sympatric situations are numerous, recurrent homoploid hybrid speciation is a possibility. We argue that three different, but not mutually exclusive, types of contingencies could influence this process. First, many of these ＂hopeful monsters＂ of recombinant parent genotypes would likely have low fitness. Only specific combinations of parental genomic con- tributions may produce viable, intra-fertile hybrid species able to accommodate potential constraints arising from intragenomic conflict. Second, ecological conditions （competition, geography of the contact zones or the initial frequency of both parent spe- cies） might favor different outcomes ranging from sympatric coexistence to the formation of hybrid swarms and ultimately hybrid speciation. Finally, history may also play an important role in promoting or constraining recurrent HHS if multiple hybridization events occur sequentially and parental divergence or isolation differs along this continuum. We discuss under which conditions HHS may occur multiple times in parallel and to what extent recombination and selection may fuse the parent genomes in the same or different ways. We conclude by examining different approaches that might help to solve this intriguing evolutionary puz- zle [Current Zoology 59 （5）： 667-674, 2013].

关键词： Dimensionality Genetic Mosaicism Hybridization Speciation

One-range addition theorems for generalized integer and noninteger μ Coulomb,and exponential type correlated interaction potentials with hyperbolic cosine in position,momentum,and four-dimensional spaces

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Chinese Physics B 2012年第6期21卷 137-140页

作者： i.i.Guseinov Department of Physics Faculty of Arts and SciencesOnsekiz Mart UniversityCanakkaleTurkey

The formulae are established in position,momentum,and four-dimensional spaces for the one-range addition theorems of generalized integer and noninteger μ Coulomb,and exponential type correlated interaction potentials with hyperbolic cosine（GCTCP and GETCP HC）.These formulae are expressed in terms of one-range addition theorems of complete orthonormal sets of Ψα-exponential type orbitals（Ψ α-ETO）,α-momentum space orbitals（α-MSO）,and zα-hyperspherical harmonics（zα-HSH） *** one-range addition theorems obtained can be useful in the electronic structure calculations of atoms and molecules when the GCTCP and GETCP HC in position,momentum,and four-dimensional spaces are employed.

关键词： correlated interaction potentials one-range additional theorems complete orthonormalsets of orbitals overlap integrals