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Sex roles and sexual selection： lessons from a dynamic model system

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Current Zoology 2018年第3期64卷 363-392页

作者： Trond amundsen Department of Biology Norwegian University of Science and Technology NO 7491 Trondheim Norway

Our understanding of sexual selection has greatly improved during the last decades. The focus is no longer solely on males, but also on how female competition and male mate choice shape ornamentation and other sexually selected traits in females. At the same time, the focus has shifted from documenting sexual selection to exploring variation and spatiotemporal dynamics of sexual selection, and their evolutionary consequences. Here, i review insights from a model system with exceptionally dynamic sexual selection, the two-spotted goby fish Gobiusculus flavescens. The species displays a complete reversal of sex roles over a 3-month breeding season. The reversal is driven by a dramatic change in the operational sex ratio, which is heavily male-biased at the start of the season and heavily female-biased late in the season. Early in the season, breeding-ready males outnumber mature females, causing males to be highly competitive, and leading to sexual selection on males. Late in the season, mating-ready females are in excess, engage more in courtship and aggression than males, and rarely reject mating opportunities. With typically many females simultaneously courting available males late in the season, males become selective and prefer more colorful females. This variable sexual selection regime likely explains why both male and female G. flavescens have ornamental colors. The G. flavescens model system reveals that sexual behavior and sexual selection can be astonishingly dynamic in response to short-term fluctuations in mating competition. Future work should explore whether sexual selection is equally dynamic on a spatial scale, and related spatiotemporal dynamics.

关键词： adult sex ratio female ornament Gobiusculus flavescens male ornament mate choice mate search mating compe-tition operational sex ratio OSR two-spotted goby

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

Apolipoprotein A-i binding protein-mediated neuroprotection in glaucomatous neuroinflammation and neurodegeneration

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Neural Regeneration Research 2025年第5期20卷 1414-1415页

作者： Sinwoo Hwang Seunghwan Choi Soo-Ho Choi Keun-Young Kim Yury i.Miller Won-Kyu Ju Hamilton Glaucoma Center and Shiley Eye institute The Viterbi Family Department of OphthalmologyUniversity of California San DiegoLa JollaCAUSA Department of Medicine University of California San DiegoLa JollaCAUSA National Center for Microscopy and imaging Research Department of NeurosciencesUniversity of California San DiegoLa JollaCAUSA

Glaucoma is a multifactorial eye disorder that can cause vision loss and irreversible blindness,affecting individ uals aged 40 to 80 yea rs *** to the aging population,it is expected that the number of people affected by glaucoma will surpass 111 million by 2040 as the disease becomes more *** primarily contributes to optic nerve axon loss and the progressive degeneration of retinal ganglion cells (RGCs),subsequently leading to vision impairment.

关键词： irreversible pass primarily

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

ischemia/reperfusion injury in porcine intestine-Viability assessment

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World Journal of Gastroenterology 2018年第18期24卷 2009-2023页

作者： Runar J Strand-amundsen Henrik M Reims Finn P Reinholt Tom E Ruud Runkuan Yang Jan O Hogetveit Tor i Tonnessen Department of Clinical and Biomedical Engineering Oslo University HospitalOslo 0424Norway Department of Physics University of OsloOslo 0316Norway Department of Pathology Oslo University HospitalOslo 0424Norway institute for Surgical Research Oslo University HospitalOslo 0424Norway Department of Surgery Baerum HospitalVestre Viken Hospital TrustDrammen 3004Norway Department of Emergencies and Critical Care Oslo University HospitalOslo 0424Norway institute of Clinical Medicine University of OsloOslo 0424Norway

AiM To investigate viability assessment of segmental small bowel ischemia/reperfusion in a porcine *** in 15 pigs, five or six 30-cm segments of jejunum were simultaneously made ischemic by clamping the mesenteric arteries and veins for 1 to 16 h. Reperfusion was initiated after different intervals of ischemia(1-8 h) and subsequently monitored for 5-15 h. The intestinal segments were regularly photographed and assessed visually and by palpation. intraluminal lactate and glycerol concentrations were measured by microdialysis, and samples were collected for light microscopy and transmission electron microscopy. The histological changes were described and *** Using light microscopy, the jejunum was considered as viable until 6 h of ischemia, while with transmission electron microscopy the ischemic muscularis propria was considered viable until 5 h of ischemia. However, following ≥ 1 h of reperfusion, only segments that had been ischemic for ≤ 3 h appeared viable, suggesting a possible upper limit for viability in the porcine mesenteric occlusion model. Although intraluminal microdialysis allowed us to closely monitor the onset and duration of ischemia and the onset of reperfusion, we were unable to find sufficient level of association between tissue viability and metabolic markers to conclude that microdialysis is clinically relevant for viability assessment. Evaluation of color and motility appears to be poor indicators of intestinal *** Three hours of total ischemia of the small bowel followed by reperfusion appears to be the upper limit for viability in this porcine mesenteric ischemia model.

关键词： Viability histology reperfusion ischemia microdialysis jejunum porcine model

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

High rate of clinically relevant improvement following anatomical total shoulder arthroplasty for glenohumeral osteoarthritis

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World Journal of Orthopedics 2024年第2期15卷 156-162页

作者： Marc Randall Kristensen Nyring Bo Sanderhoff Olsen Alexander amundsen Jeppe Vejlgaard Rasmussen Section for Shoulder and Elbow Surgery Department of Orthopaedic SurgeryHerlev and Gentofte University HospitalHellerup 2900Denmark

BACKGROUND The minimal clinically important difference(MCiD)is defined as the smallest meaningful change in a health domain that a patient would identify as ***,an improvement that exceeds the MCiD can be used to define a successful treatment for the individual *** To quantify the rate of clinical improvement following anatomical total shoulder arthroplasty for glenohumeral *** Patients were treated with the Global Unite total shoulder platform arthroplasty between March 2017 and February 2019 at Herlev and Gentofte Hospital,*** patients were evaluated preoperatively and 3 months,6 months,12 months,and 24 months postoperatively using the Western Ontario Osteoarthritis of the Shoulder index(WOOS),Oxford Shoulder Score(OSS)and Constant-Murley Score(CMS).The rate of clinically relevant improvement was defined as the proportion of patients who had an improvement 24 months postoperatively that exceeded the *** on previous literature,MCiD for WOOS,OSS,and CMS were defined as 12.3,4.3,and 12.8 *** Forty-nine patients with a Global Unite total shoulder platform arthroplasty were included for the final *** age at the time of surgery was 66 years(range 49.0-79.0,SD:8.3)and 65%were *** patient was revised within the two years *** mean improvement from the preoperative assessment to the two-year follow-up was 46.1 points[95%confidence interval(95%Ci):39.7-53.3,Pints(95%Ci:15.5-21.0,Pints(95%Ci:31.5-44.0,Pively,41 patients(87%)had an improvement in WOOS that exceeded the MCiD,45 patients(94%)had an improvement in OSS that exceeded the MCiD,and 42 patients(88%)had an improvement in CMS that exceeded the *** Based on three shoulder-specific outcome measures we find that approximately 90%of patients has a clinically relevant *** is a clear message when informing patients about the

关键词： Minimal clinically important difference Patient reported outcome measures Glenohumeral osteoarthritis Anatomical total shoulder arthroplasty Clinically relevant improvement