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Efficient Handling of Lock Hand-off in DSM Multiprocessors with Buffering Coherence Controllers

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Journal of Computer Science & Technology 2012年第1期27卷 75-91页

作者： Benjamín Sahelices Agustín de Dios Pablo Ibáez Víctor Vials-Yúfera José maría Llabería Computer Science Department and HiPEAC European Network of Excellence University of Valladolid Valladolid Spain Computer Science and Systems Engineering Department I3A Research Institute and HiPEAC European Network of Excellence University of Zaragoza Zaragoza Spain Computer Architecture Department and HiPEAC European Network of Excellence Polytechnic University of Catalua Barcelona Spain

Synchronization in parallel programs is a major performance bottleneck in multiprocessor systems. Shared data is protected by locks and a lot of time is spent on the competition arising at the lock hand-off. In order to be serialized, requests to the same cache line can either be bounced （NACKed） or buffered in the coherence controller. In this paper, we focus mainly on systems whose coherence controllers buffer requests. In a lock hand-off, a burst of requests to the same line arrive at the coherence controller. During lock hand-off only the requests from the winning processor contribute to progress of the computation, since the winning processor is the only one that will advance the work. This key observation leads us to propose a hardware mechanism we call request bypassing, which allows requests from the winning processor to bypass the requests buffered in the coherence controller keeping the lock line. We present an inexpensive implementation of request bypassing that reduces the time spent on all the execution phases of a critical section （acquiring the lock, accessing shared data, and releasing the lock） and which, as a consequence, speeds up the whole parallel computation. This mechanism requires neither compiler or programmer support nor ISA or coherence protocol changes. By simulating a 32-processor system, we show that using request bypassing does not degrade but rather improves performance in three applications with low synchronization rates, while in those having a large amount of synchronization activity （the remaining four）, we see reductions in execution time and in lock stall time ranging from 14% to 39% and from 52% to 7170, respectively. We compare request bypassing with a previously proposed technique called read combining and with a system that bounces requests, observing a significantly lower execution time with the bypassing scheme. Finally, we analyze the sensitivity of our results to some key hardware and software parameters.

关键词： distributed shared memory multiprocessors synchronization buffer coherence controller request bypass

Shedding light on the retina to see healthy and pathological aging

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Neural Regeneration Research 2025年第12期20卷 3537-3538页

作者： marília Inês Móvio maria Camila Almeida Sergio T.Ferreira Alexandre Hiroaki Kihara Neurogenetics Laboratory Federal University of ABCSão Bernardo do CampoSPBrazil Center for Mathematics Computing and CognitionFederal University of ABCSão Bernardo do CampoSPBrazil Center for Natural and Human Sciences Federal University of ABCSao Bernardo do CampoSPBrazil Institute of Medical Biochemistry Leopoldo de Meis Federal University of Rio de JaneiroRio de JaneiroRJBrazil Institute of Biophysics Carlos Chagas Filho Federal University of Rio de JaneiroRio de JaneiroRJBrazil

With the advances in medicine and technology,life expectancy has increased significantly in recent *** this is positive news,it also brings major challenges to public health *** people live longer,the number of cases of agerelated disorders,including neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD),has also grown.

关键词： diseases Alzheimer cases

Aging: Thromboembolic Disease, Metabolic Syndrome, Type 2 Diabetes Mellitus, and Alzheimer’s Disease

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Journal of Biosciences and Medicines 2016年第5期4卷 1-20页

作者： Joaquín Lasierra-Cirujeda maría José Aza Pascual-Salcedo Alicia Lasierra-ibañez Carmen Lasala Aza maría Mercedes Aza Pascual-Salcedo Centro Médico Hematológico Logrono Spain Pharmaceutical Act Ministry of Health La Rioja Regional Government Logrono Spain Aragon Health Service Zaragoza Spain

Aging can be interpreted as an unavoidable process whose end point is the death. Aging entails, in the hemostasis field, some changes that favour blood hypercoagulability. Both the plasminogen activator inhibitor (PAI-1), specific inhibitor of the tissue plasminogen activator (t-PA), accompanied by the oxidative stress and the marked decrease of the main antioxidant—glutathione are fundamental in the bases of elderly pathologies which can cause death. There is some scientific evidence of the relationship between aging, neuro-degenerative diseases, an excessive production of reactive oxygen species and the decrease of proteolysis in brain. The cerebral plasminogen/plasmin system represents the essential proteolytic mechanism that degrades amyloid peptides (β-amyloidosis) for action of plasmin with effectiveness. This physiologic process is being considered as a preventive neurodegenerative mechanism. At the same time, the decrease of glutathione levels in aging entails a decrease of cerebral plasmin activity and a progressive descent of t-PA activity due to a descent in t-PA expression and an increase in PAI production. All of them entail an increment of amyloid beta peptides (Aβ) production and a lower level of their clearance. Both mechanisms, oxidative stress, direct consequence of the oxygenate metabolism of aerobics cells, and changes in the systemic fibrinolysis and cerebral b-amyloidolytic activity, play a very important role in thromboembolic disease, metabolic syndrome—obesity, insulin resistance, hyperglycemia—, type 2 Diabetes Mellitus and Alzheimer’s disease, clinical processes that accompany the aging. In this revision we show the importance of the interaction between glutathione, proteolytic t-PA/plasminogen/plasmin system, and the inhibitor PAI-1 in aging physiopathology, whose results suggest the hypothesis of the importance of a therapeutic strategy using the inhibition of PAI-1 as a goal, because it is increased in the different aging pathologic pro

关键词： Aging Alzheimer’s Disease T2DM PAI-1 Glutathione

c-Abl kinase at the crossroads of healthy synaptic remodeling and synaptic dysfunction in neurodegenerative diseases

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Neural Regeneration Research 2023年第2期18卷 237-243页

作者： Daniela A.Gutiérrez América Chandía-Cristi maría JoséYáñez Silvana Zanlungo Alejandra R.Alvarez Cell Signaling Laboratory Department of Cellular and Molecular BiologyCenter for Aging and Regeneration(CARE)Millennium Institute on Immunology and ImmunotherapyBiological Sciences FacultyPontificia Universidad Católica de ChileSantiagoChile School of Medical Technology Health Sciences FacultyUniversidad San SebastianSede Los LeonesSantiagoChile Department of Gastroenterology Faculty of MedicinePontificia Universidad Católica de ChileSantiagoChile

Our ability to learn and remember depends on the active formation,remodeling,and elimination of ***,the development and growth of synapses as well as their weakening and elimination are essential for neuronal *** structural reorganization of synaptic complexes,changes in actin cytos keleton and organelle dynamics,as well as modulation of gene expression,determine synaptic *** has been proposed that dys regulation of these key synaptic homeostatic processes underlies the synaptic dysfunction observed in many neurodegenerative *** is known about downstream signaling of activated N-methyl-D-aspartate andα-amino-3-hydroxy-5-methyl-4-isoazolepro pionate receptors;howeve r,other signaling pathways can also contribute to synaptic plasticity and long-lasting changes in learning and *** non-receptor tyrosine kinase c-Abl(ABL1)is a key signal transducer of intra and extracellular signals,and it shuttles between the cyto plasm and the *** review focuses on c-Abl and its synaptic and neuronal ***,we discuss the evidence showing that the activation of c-Abl can be detrimental to neurons,promoting the development of neurodegenerative ***,c-Abl activity seems to be in a pivotal balance between healthy synaptic plasticity,regulating dendritic spines remodeling and gene expression after cognitive training,and synaptic dysfunction and loss in neurodegenerative ***,c-Abl genetic ablation not only improves learning and memory and modulates the brain genetic program of trained mice,but its absence provides dendritic spines resiliency against *** re,the present review has been designed to elu cidate the common links between c-Abl regulation of structural changes that involve the actin cytos keleton and organelles dynamics,and the transc riptional program activated during synaptic *** summarizing the recent discove ries on c-Abl functions,we aim to provide an overview of how

关键词： actin cytoskeleton activity-dependent plasticity Alzheimer's disease c-Abl dendritic spines learning synapse synaptic plasticity transcription tyrosine kinase

The ILux^(®) compared to the mechanical meibomian gland expression for the treatment of moderate and severe meibomian gland dysfunction

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1042-1048页

作者： maría Ximena Núñez Andrea Acosta-Ortega Guillermo Raul Vera-Duarte Catalina Gómez-Duarte Unit of Cornea Cataract and Refractive SurgeryVision Sana Research GroupClínica de Oftalmología de CaliFaculty of Medicine Pontificia Universidad Javeriana CaliCali 760031Colombia Department of Ophthalmology Faculty of Medicine Pontificia Universidad Javeriana CaliCali 760031Colombia Department of Ophthalmology Hospital de ClínicasNational University of AsunciónAsunción 111421Paraguay

AIM:To compare the safety and effectiveness of eyelid treatment with the ILux®-MGD Treatment System in one session versus five sessions of mechanical meibomian gland expression(MMGE)in patients with moderate to severe meibomian gland dysfunction(MGD).METHODS:A prospective,randomized,open-label,and controlled clinical trial that compared one session of the ILux®MGD Treatment System versus five sessions of MMGE in both eyes of 130 patients aged≥18y with Ocular Surface Disease Index(OSDI)scores≥13,total meibomian gland scores(MGS)of<15 in the lower eyelid of each eye,and non-invasive tear break-up time(NI-TBUT)<10s,who were randomized 1:1 to ILux®or ***:The mean age was 58±*** total MGS scores in both treatment groups were *** follow-up,there were significant differences in total MGS and per sector with P<*** analysis was performed using generalized estimating equations corresponding to the generalized linear model for repeated means to determine the treatment relationship with total MGS,NIBUT,and *** was a significant difference between ILux®and MMGE(P<0.001)at follow-up from the first to the twelfth month in MGS,NI-BUT,and OSDI *** adverse events were ***:ILux®treatment compared to MMGE significantly improves symptoms and signs in patients with moderate to severe MGD for one year without adverse events.

关键词： meibomian gland dysfunction ILux® ocular surface dry eye

The Holocene Evolution ofthe Ebre Delta Catalonia, Spain

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地理学报 1999年第5期54卷 462-469页

作者： Antoni Canicio 1,Carles iban～ez 2 (1 C/Major 10, 43580 Deltebre, Spain 2 Department of Ecology University of Barcelona Barcelona, Spain) C/Major 10 43580 Deltebre Spain 西班牙 043580 University of Barcelona 西班牙

The existing scientific literature about the Ebre delta states that it formed in very recent times (mostly since the middle ages) and that in Roman times it was an estuary. This belief is based on erroneous interpretation of historical data, rather than on scientific evidence. We present the first data about the position of early coastlines based on radiocarbon dating. The evidence proves the existence of the Ebre delta as much as 5 750 a BP. Another early coastline that dates to 3 045 a BP has also been identified. Using this information and other sources such as old maps and present day bathymetry of old eroded deltaic lobes, we constructed the first evolutionary sequence of the Ebre delta during the Holocene. Cartographic information was carefully and critically assessed in the process of selecting those maps that are coherent with geomorphic structures. Details about the evolution of deltaic lobes are only given for the last millennium. The development of the southern lobe was at its maximum about 1 ka BP. By the 16th century the lobe had already been strongly reshaped (maximum retreat about 8 km) after the abandonment of the old river arm. At that time the Ebre delta already had developed a surface similar to that of the present. The maximum penetration of the lobe into the sea (about 25 km) is clearly indicated in bathymetric maps. During the 17th century the northern lobe reached its maximum extent (also about 25 km), and at the end of that century the central lobe (the one presently active) started to form, reaching its maximum growth (again about 25 km) by the beginning of the 20th century.

关键词： Ebre River delta discharge sediment load Holocene

Synthesis of activated carbons from black sapote seeds,characterization and application in the elimination of heavy metals and textile dyes

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Chinese Journal of Chemical Engineering 2020年第2期28卷 613-623页

作者： Alejandra Alicia Peláez-Cid Vincent Romero-Hernández Ana maría Herrera-González Alejandro Bautista-Hernández Oscar Coreno-Alonso Facultad de Ingeniería Benemérita Universidad Autónoma de PueblaMexico Instituto de Ciencias Básicas e Ingeniería Universidad Autónoma del Estado de HidalgoMexico División de Ingenierías Universidad de GuanajuatoMexico

Many different techniques may be used to remove industrial pollutants from wastewater. Adsorption using activated carbon has been reported to be an effective method. This work proposes the use of a vegetable residue(black sapote seeds) as a raw material for its synthesis. These carbons were chemically activated using phosphoric acid and carbonized at 673 and 873 K. Adsorption isotherms were constructed for the textile dyes on the carbons, and this data was treated using Langmuir’s equation to quantitatively describe the adsorption process. The synthesized carbons were characterized using FTIR, EA, SEM, Nitrogen adsorption(specific surface areas of 879 and 652 m2·g-1), and their points of zero charge(2.1 and 2.3). It was possible to adsorb both heavy metals and textile dyes present in aqueous solutions and wastewaters using these activated carbons. Heavy metals were adsorbed almost completely by both carbons. Cationic dyes where adsorbed(58–59.8 mg·g-1) in greater amounts compared to anionic dyes(10–58.8 mg·g-1). The amount of anionic dyes adsorbed increased almost 30% by changing the pH of the solutions. One of the carbons was thermally regenerated on three occasions without losing its adsorption capacity and it was proved in a flow system.

关键词： Activated carbons Black sapote seeds Heavy metal adsorption Textile dye adsorption Wastewater treatment

Dynamics of canopy-dwelling arthropods under different weed management options,including glyphosate,in conventional and genetically modified insect-resistant maize

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Insect Science 2021年第4期28卷 1121-1138页

作者： Esteban García-Ruiz Guillermo Cobos Ismael Sánchez-Ramos Susana Pascual maría-Cristina Chueca maría-Concepción Escorial Inés Santín-Montanyá Íñigo Loureiro Manuel González-Núñez Plant Protection Department Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria(INIA)MadridSpain

The use of genetically modified varieties tolerant to herbicides(HT varieties)and resistant to insects(Bt varieties)in combination with application of a broad-spectrum herbicide such as glyphosate could be an effective option for the simultaneous control of weeds and pests in ***,the possible impact of these tools on nontarget arthropods still needs to be *** a field study in central Spain,potential changes in populations of canopy-dwelling arthropods in Bt maize under different weed management options,including glyphosate application,were ***-dwelling arthropods were sampled by visual inspection and yellow sticky *** Bt variety had no effect on any group of studied arthropods,except for the expected case of corn borers—the target pests of Bt *** the effects of herbicide regimes,the only observed difference was a lower abundance of Cicadellidae and Mymaridae on yellow sticky traps in plots not treated with pre-emergence *** effect was especially pronounced in a treatment involving two glyphosate *** decrease in Cicadellidae and Mymaridae populations was associated with a higher density of weeds in plots,which may have hindered colonization of the crop by *** differences,however,were only significant in the last year of the *** low likelihood of the use of glyphosate-and herbicide-tolerant varieties for weed control triggering important effects on the nontarget arthropod fauna of the maize canopy is discussed.

关键词： Bt maize canopy-dwelling arthropods GMHT maize glyphosate herbicide management parasitoids

ddRAD sequencing-based genotyping for population structure analysis in cultivated tomato provides new insights into the genomic diversity of Mediterranean‘da serbo’type long shelf-life germplasm

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Horticulture Research 2020年第1期7卷 1047-1060页

作者： Salvatore Esposito Teodoro Cardi Gabriele Campanelli Sara Sestili maría JoséDíez Salvador Soler Jaime Prohens Pasquale Tripodi CREA Research Centre for Vegetable and Ornamental Crops Pontecagnano(SA)Italy CREA Research Centre for Vegetable and Ornamental Crops Monsampolo del Tronto(AP)TrontoItaly Instituto de Conservación y Mejora de la Agrodiversidad Valenciana Universitat Politècnica de València46022 ValenciaSpain

Double digest restriction-site associated sequencing(ddRAD-seq)is a flexible and cost-effective strategy for providing in-depth insights into the genetic architecture of germplasm *** this methodology,we investigated the genomic diversity of a panel of 288 diverse tomato(Solanum lycopersicum L.)accessions enriched in‘da serbo’(called‘de penjar’in Spain)long shelf life(LSL)materials(152 accessions)mostly originating from Italy and *** rest of the materials originate from different countries and include landraces for fresh consumption,elite cultivars,heirlooms,and breeding *** from their LSL trait,‘da serbo’landraces are of remarkable interest for their *** identified 32,799 high-quality SNPs,which were used for model ancestry population structure and non-parametric hierarchical *** genetic subgroups were revealed,clearly separating most‘da serbo’landraces,but also the Spanish germplasm,suggesting a subdivision of the population based on type and geographical *** disequilibrium(LD)in the collection decayed very rapidly within<5 *** then investigated SNPs showing contrasted minor frequency allele(MAF)in‘da serbo’materials,resulting in the identification of high frequencies in this germplasm of several mutations in genes related to stress tolerance and fruit maturation such as CTR1 and ***,a mini-core collection of 58 accessions encompassing most of the diversity was selected for further exploitation of key *** findings suggest the presence of a genetic footprint of the‘da serbo’germplasm selected in the Mediterranean ***,we provide novel insights on LSL‘da serbo’germplasm as a promising source of alleles for tolerance to stresses.

关键词： germplasm breeding shelf