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Geographic variation in growth and phenology of two dominant central US grasses:consequences for climate change

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Journal of Plant Ecology 2014年第3期7卷 211-221页

作者： Amanda L.Giuliani Eugene F.kelly alan k.knapp Department of Biology Colorado State UniversityFort CollinsCO 80523USA Department of Soils and Crops Science Colorado State UniversityFort CollinsCO 80523USA Graduate Degree Program in Ecology and Department of Biology Colorado State UniversityFort CollinsCO 80523USA

Aims The rate of climate change may exceed many plant species’migration rates,particularly for long-lived perennial species that dominate most *** bioclimatic envelopes shift more rapidly than dominant species can migrate,individuals located peripheral to biomes or in adjacent biomes may become a significant source of traits for future dominant populations(DPs).Thus,traits of individuals from peripheral populations(PPs)may affect future ecosystem functioning more than those of today’s *** We assessed key traits of individuals collected from populations that currently dominate two central US grasslands,the shortgrass steppe(Bouteloua gracilis)and the tallgrass prairie(Andropogon gerardii).We compared these to individuals from PPs in a reciprocal-transplant common garden experiment with gardens at the Shortgrass Steppe Long Term Ecological Research site in Colorado and the konza Prairie Biological Station Long Term Ecological Research site in *** and PPs were subjected to high and reduced water availability in common gardens located in each *** measured included the following:individual plant biomass,reproductive allocation,specific leaf area(SLA)and plant–water *** focused on the climate-change relevant comparisons of traits from PPs versus DPs expressed under the climate of *** Findings PPs of *** differed from DPs primarily in phenological *** a semiarid shortgrass steppe climate,PPs initiated flowering later in the season,produced fewer reproductive tillers and were more sensitive to water *** differences between populations were *** ***,biomass in PPs was 50%lower than in DPs under the mesic tallgrass prairie climate and reproductive tillers were considerably smaller,despite higher SLA in *** of PPs was less sensitive to water stress,*** these results,we conclude that key traits of PPs differed from DPs in both grassland types,but potential effects on r

关键词： grassland phenology productivity traits water stress

Efficiently adding mode multiplexing for cost-effective,high-capacity fiber links

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Advanced Photonics 2024年第1期6卷 8-9页

作者： alan E.Willner Huibin Zhou University of Southern California Los AngelesCaliforniaUnited States

For decades,a powerful approach to adding data capacity in an optical communication link has been to multiplex independent data-carrying channels and transmit them simultaneously along a fiber.^(1)For example,wavelength-division-multiplexing(WDM)was a key technology in the 1990s and early 2000s to dramatically increase aggregate capacity in a fiber by multiplexing beams of different wavelengths.^(2)For the past roughly 15 years,there has been great promise that space-division-multiplexing(SDM)may bring similar capacity enhancements to optical fiber communications.^(1–3)

关键词： fiber multiplexing adding

Distributed Mallows Model Averaging for Ridge Regressions

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Acta Mathematica Sinica,English Series 2024年

作者： Haili ZHANG alan T.k.WAN kang YOU Guohua ZOU School of Mathematical Sciences Capital Normal University Institute of Applied Mathematics Shenzhen Polytechnic University Department of Management Sciences and School of Data Science City University of Hong Kong

Ridge regression is an effective tool to handle multicollinearity in regressions. It is also an essential type of shrinkage and regularization methods and is widely used in big data and distributed data applications. The divide and conquer trick, which combines the estimator in each subset with equal weight, is commonly applied in distributed data. To overcome multicollinearity and improve estimation accuracy in the presence of distributed data, we propose a Mallows-type model averaging method for ridge regressions, which combines estimators from all subsets. Our method is proved to be asymptotically optimal allowing the number of subsets and the dimension of variables to be *** consistency of the resultant weight estimators tending to the theoretically optimal weights is also derived. Furthermore, the asymptotic normality of the model averaging estimator is *** simulation study and real data analysis show that the proposed model averaging method often performs better than commonly used model selection and model averaging methods in distributed data cases.

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Reliability of a computerized system for strabismus screening

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 126-130页

作者： Supaporn Tengtrisorn alan Frederick Geater Department of Ophthalmology Faculty of MedicinePrince of Songkla UniversityHat-YaiSongkla 90110Thailand Epidemiology Unit Faculty of MedicinePrince of Songkla UniversityHat-YaiSongkla 90110Thailand

AIM:To evaluate the reliability of Photo-Hirschberg screening for global strabismus performed by non-specialized ***:Participants at three sites were *** person at each site was trained in visual acuity measurement and use of the computerized *** acuity was measured,and strabismus testing was performed using two flash *** data from the three primary observers were sent to an experienced assistant researcher,who was blinded to the primary results,for *** primary and re-evaluation results of the Photo-Hirschberg screenings using weighted kappa for agreement were ***:The study included 181 participants(88 males and 93 females)and the results for primary and re-evaluation screenings were *** participants with contrasting results presented with unclear corneal light *** and specificity were 100%[95%confidence interval(CI):29.0%-100%]and 99.4%(95%CI:96.6%-100%),respectively,based on the Agresti test of the primary evaluation,considering the re-evaluated classification as ***:The computerized system can be used for primary strabismus screening by non-specialized personnel,with 98.8%agreement with ***,it cannot be used as a substitute for professional examination.

关键词： strabismus screening computerized system Photo-Hirschberg screening

Soleus arthrogenic muscle inhibition following acute lateral ankle sprain correlates with symptoms and ankle disability but not with postural control

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Journal of Sport and Health Science 2024年第4期13卷 559-568,F0003页

作者： kyung-Min kim Joo-Sung kim alan R.Needle Department of Sport Science Sungkyunkwan UniversitySuwon-si 16419Republic of Korea Department of Health and Human Performance Texas State UniversitySan MarcosTX 78666USA Department of Public Health&Exercise Science Appalachian State UniversityBooneNC 28608USA Department of Rehabilitation Science Appalachian State UniversityBooneNC 28608USA

Background:Acute lateral ankle sprains(ALAS)are associated with long-term impairments and instability tied to altered neural *** muscle inhibition(AMI)has been observed in this population;however,relationships with injury-related impairments are unclear,potentially due to the resting,prone position in which AMI is typically *** AMI during bipedal stance may provide a better understanding of this ***:AMI was assessed in 38 young adults(19 ALAS within 72 h of injury:10 males,21.4±2.7 years;19 healthy controls:10 males,21.9±2.2 years;mean±SD)using the Hoffmann reflex(H-reflex)during bipedal *** stimulation was administered to identify the _(max)imal H-reflex(H_(max))and _(max)imal motor response(M_(max))from the soleus,fibularis longus,and tibialis anterior *** primary outcome measure was the H_(max)/M_(max) *** outcomes included acute symptoms(pain and swelling),postural control during bipedal stance,and self-reported ***:No significant group-by-limb interactions were observed for any ***,a significant group main effect was observed in the soleus muscle(F(1,35)=6.82,p=0.013),indicating significantly lower H_(max)/M_(max) ratios following ALAS(0.38±0.20)compared to healthy controls(0.53±0.16).Furthermore,lower H_(max)/M_(max) ratios in the soleus significantly correlated with acute symptoms and self-reported function but not with postural ***:This study supports previous evidence of AMI in patients with ALAS,providing insight into neurophysiologic impacts of musculoskeletal *** results suggest that assessing AMI in a standing position following acute injury may provide valuable insight into how AMI develops and guide potential therapeutic options to curb and offset the formation of joint instability.

关键词： Acute injuries Balance Hoffmann reflex Neural excitability Patient-reported outcomes

Modeling mitochondria,where are the numbers?

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Neural Regeneration Research 2024年第7期19卷 1435-1436页

作者： Adrian M.Davies alan G.Holt University Center Shrewsbury ShrewsburyShropshireUK

Models and simulations are particularly useful for exploring ideas and concepts in the biological sciences that are expe rimentally *** silico methods are also gaining acceptance with regulatory authorities as an alte... 详细信息

关键词： eliminate authorities acceptance

Acquiring Weak Annotations for Tumor Localization in Temporal and Volumetric Data

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Machine Intelligence Research 2024年第2期21卷 318-330页

作者： Yu-Cheng Chou Bowen Li Deng-Ping Fan alan Yuille Zongwei Zhou Department of Computer Science Johns Hopkins UniversityBaltimore 21218USA Computer Vision Lab ETH ZurichZurich 8001Switzerland

Creating large-scale and well-annotated datasets to train AI algorithms is crucial for automated tumor detection and ***,with limited resources,it is challenging to determine the best type of annotations when annotating massive amounts of unlabeled *** address this issue,we focus on polyps in colonoscopy videos and pancreatic tumors in abdominal CT scans;Both applications require significant effort and time for pixel-wise annotation due to the high dimensional nature of the data,involving either temporary or spatial *** this paper,we develop a new annotation strategy,termed Drag&Drop,which simplifies the annotation process to drag and *** annotation strategy is more efficient,particularly for temporal and volumetric imaging,than other types of weak annotations,such as per-pixel,bounding boxes,scribbles,ellipses and ***,to exploit our Drag&Drop annotations,we develop a novel weakly supervised learning method based on the watershed *** results show that our method achieves better detection and localization performance than alternative weak annotations and,more importantly,achieves similar performance to that trained on detailed per-pixel ***,we find that,with limited resources,allocating weak annotations from a diverse patient population can foster models more robust to unseen images than allocating per-pixel annotations for a small set of *** summary,this research proposes an efficient annotation strategy for tumor detection and localization that is less accurate than per-pixel annotations but useful for creating large-scale datasets for screening tumors in various medical modalities.

关键词： Weak annotation detection localization segmentation colonoscopy abdomen

Excess dietary Lys reduces feed intake, stimulates jejunal CCk secretion and alters essential and non‑essential blood AA profile in pigs

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1336-1346页

作者： Maximiliano Muller Elout Van Liefferinge alan Tilbrook Robert van Barneveld Eugeni Roura Centre for Nutrition and Food Sciences Queensland Alliance for Agriculture and Food InnovationThe University of QueenslandBrisbaneQueensland 4072Australia Laboratory of Animal Nutrition and Animal Product Quality(LANUPRO) Department of Animal Sciences and Aquatic EcologyGhent University339000 GhentFlandersBelgium Centre for Animal Science Queensland Alliance for Agriculture and Food Innovation and the School of Veterinary ScienceThe University of QueenslandBrisbaneQueensland 4072Australia SunPork Group BrisbaneQueensland 4009Australia

Background Commercial diets are frequently formulated to meet or exceed nutrient levels including those of lim-iting essential amino acids(AA)covering potential individual variations within the ***,the provision of dietary excess of AA,such as Lys,may lead to reduced appetite and growth in *** mechanisms modulat-ing these responses have not been extensively *** study evaluated the effect of Lys dietary excesses on performance and satiety biomarkers in post weaning *** Twenty-four pigs aged 21 d and weighing 6.81±0.12kg(mean±SEM)were individually housed and offered 1 of 4 dietary treatments for 3weeks:a diet containing a standardized ileal digestible Lys reaching 100%(T0),120%(T1),150%(T2)or 200%(T3)of the NRC(2012)*** the end of the experiment,blood samples from the cephalic vein of the T0 and T3 groups were obtained for AA *** addition,primary intestinal cultures from T0 pigs were used,following their humane killing,to evaluate the effect of Lys on gut hormone secretion and AA sensors gene expression under ex vivo *** Feed intake was linearly reduced(Pk post weaning,*** con-centration(P<0.05)and the metabotropic glutamate receptor 1 and the solute carrier family 7 member 2(P<0.10)gene expression was enhanced in proximal jejunum tissues incubated with Lys at 20mmol/L when compared to the control(Lys 0mmol/L).Plasma Lys and Glu(P<0.05)concentration increased in the T3 compared to T0 *** contrast,plasma levels of His,Val,Thr,Leu(P<0.05)and Gln(P<0.10)were lower in T3 than T0 *** The present results confirm that excess dietary Lys inhibits hunger in ***,the results provide evidence of pre-and post-absorptive mechanisms modulating these *** dietary excesses should be nar-rowed,when possible,to avoid negative effects of

关键词： Amino acid Blood Cholecystokinin Feed intake Lysine Pig Satiety

A new perspective on intervertebral disc calcification—from bench to bedside

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Bone Research 2024年第1期12卷 50-61页

作者： Emanuel J.Novais Rajkishen Narayanan Jose A.Canseco koen van de Wetering Christopher k.kepler alan S.Hilibrand Alexander R.Vaccaro Makarand V.Risbud Department of Orthopaedic Surgery Sidney Kimmel Medical CollegeThomas Jefferson UniversityPhiladelphiaPAUSA Unidade Local de Saúde do Litoral Alentejano Orthopedic DepartmentSantiago do CacémPortugal Rothman Orthopedic Institute at Thomas Jefferson University PhiladelphiaPAUSA

Disc degeneration primarily contributes to chronic low back and neck ***,there is an urgent need to understand the spectrum of disc degeneration phenotypes such as fibrosis,ectopic calcification,herniation,or mixed *** these phenotypes,disc calcification is the least *** calcification,by definition,is the pathological mineralization of soft tissues,widely studied in the context of conditions that afflict vasculature,skin,and ***,disc calcification is associated with poor surgical outcomes and back pain refractory to conservative *** is frequently seen as a consequence of disc aging and progressive degeneration but exhibits unique molecular and morphological characteristics:hypertrophic chondrocyte-like cell differentiation;TNAP,ENPP1,and ANk upregulation;cell death;altered Pi and PPi homeostasis;and local *** studies in mouse models have provided a better understanding of the mechanisms underlying this *** is essential to recognize that the presentation and nature of mineralization differ between AF,NP,and EP ***,the combination of anatomic location,genetics,and environmental stressors,such as aging or trauma,govern the predisposition to ***,the systemic regulation of calcium and Pi metabolism is less important than the local activity of PPi modulated by the ANk-ENPP1 axis,along with disc cell death and differentiation *** there is limited understanding of this phenotype,understanding the molecular pathways governing local intervertebral disc calcification may lead to developing disease-modifying drugs and better clinical management of degeneration-related pathologies.

关键词： degeneration metabolism intervertebral