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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

Meningeal lymphatic vessel crosstalk with central nervous system immune cells in aging and neurodegenerative diseases

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Neural Regeneration Research 2025年第3期20卷 763-778页

作者： Minghuang Gao Xinyue Wang Shijie Su Weicheng Feng Yaona Lai Kongli Huang Dandan Cao Qi Wang Science and Technology innovation Center Guangzhou University of Chinese MedicineGuangzhouGuangdong ProvinceChina Institute of Clinical Pharmacology Guangzhou University of Chinese MedicineGuangzhouGuangdong ProvinceChina The Sixth Affiliated Hospital Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Meningeal lymphatic vessels form a relationship between the nervous system and periphery, which is relevant in both health and disease. Meningeal lymphatic vessels not only play a key role in the drainage of brain metabolites but also contribute to antigen delivery and immune cell activation. The advent of novel genomic technologies has enabled rapid progress in the characterization of myeloid and lymphoid cells and their interactions with meningeal lymphatic vessels within the central nervous system. In this review, we provide an overview of the multifaceted roles of meningeal lymphatic vessels within the context of the central nervous system immune network, highlighting recent discoveries on the immunological niche provided by meningeal lymphatic vessels. Furthermore, we delve into the mechanisms of crosstalk between meningeal lymphatic vessels and immune cells in the central nervous system under both homeostatic conditions and neurodegenerative diseases, discussing how these interactions shape the pathological outcomes. Regulation of meningeal lymphatic vessel function and structure can influence lymphatic drainage, cerebrospinal fluid-borne immune modulators, and immune cell populations in aging and neurodegenerative disorders, thereby playing a key role in shaping meningeal and brain parenchyma immunity.

关键词： central nervous system meningeal lymphatic vessels immunity myeloid cells lymphatic cells neurodegenerative disease

Regulation of heme biosynthesis and transport in metazoa

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Science China(Life Sciences) 2015年第8期58卷 757-764页

作者： SUN FengXiu CHENG YongJiao CHEN CaiYong College of Life Sciences and innovation Center for Cell Signaling network Zhejiang University

Heine is an iron-containing tetrapyrrole that plays a critical role in regulating a variety of biological processes including oxy- gen and electron transport, gas sensing, signal transduction, biological clock, and microRNA processing. Most metazoan cells synthesize heine via a conserved pathway comprised of eight enzyme-cataiyzed reactions. Heme can also be acquired from food or extracellular environment. Cellular heine homeostasis is maintained through the coordinated regulation of synthesis, transport, and degradation. This review presents the current knowledge of the synthesis and transport of heine in metazoans and highlights recent advances in the regulation of these pathways.

关键词： heme iron synthesis transport regulation

QUANTIFYING NANOP ARTICLE TRANSPORT IN VIVO USING HYP ERSPECTRAL IMA GING WITH A DORSAL SKINFOLD WINDOW CHAMBER

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Journal of Innovative Optical health Sciences 2012年第4期5卷 8-17页

作者： TREVOR D.MCKEE JUAN CHEN IAN CORBIN GANG ZHENG RAMA KHOKHA Ontario Cancer Institute University health network TorontoOntario STTARR innovation Center University health network TorontoCanada Department of Medical Biophysics University of Toronto TorontoCanada Advanced Imaging Research Center University of Texas Southwestern Medical Center at Dallas Dallas USA

We have developed a noninv asive imaging method to quantify in viwo drug delivery pharmaco-kinetics without the need for blood or tissue collection to determine drug *** combining the techniques of hy perspectral imaging and a dorsal skinfold window chamber,this method enabled the real-time monitoring of vascular transport and tissue deposition of nano-particles labeled with near infrared(NIR)*** this imaging method,we quantified the delivery pharmacokinetics of the native high-density lipoprotein(HDL)and epidermal growth factor receptor(EGFR)-targeted HDL nanoparticles and demonstrated these HDLs had long circulation time in blood stream(half-life>12h).These HDL nanoparticles could eficiently carry cargo DiR-BOA to extravasate from blood vesels,difuse through extr acellular matrix,and penetrate and be retained in the tumor *** EGFR targeting specificity of EGFR-targeted HDL(EGFR-specific peptide conjugated HDL)was also visualized in vivo by competitive inhi bition with excess EGFR specifc *** summary,this imaging technology may help point the way toward the development of novel imaging based pharmacokinetic assays for preclinical drugs and evaluation of drug delivery eficiency,providing a dynamic window into the devel opment and application of novel drug delivery systems.

关键词： specificity kinetics competitive

Structure and electrochemical performance of delafossite AgFeO_(2)nanoparticles for supercapacitor electrodes

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 201-213页

作者： Choulong Veann Thongsuk Sichumsaeng Ornuma Kalawa Narong Chanlek Pinit Kidkhunthod Santi Maensiri School of Physics Institute of ScienceSuranaree University of TechnologyNakhon Ratchasima 30000Thailand SUT Center of excellence on Advanced Functional Materials Suranaree University of TechnologyNakhon Ratchasima 30000Thailand Synchrotron Light Research Institute Nakhon Ratchasima 30000Thailand Department of Physics Universitas Negeri MalangMalang 65145Indonesia

Delafossite AgFeO_(2)nanoparticles with a mixture of 2H and 3R phases were successfully fabricated by using a simple co-precipitation *** resulting precursor was calcined at temperatures of 100,200,300,400,and 500℃to obtain the delafossite AgFe0_(2)*** morphology and microstructure of the prepared AgFeO_(2)samples were characterized by using field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),N_(2) adsorption/desorption,X-ray absorption spectroscopy(XAS),and Xray photoelectron spectroscopy(XPS)techniques.A three-electrode system was employed to investigate the electrochemical properties of the delafossite AgFeO_(2)nanoparticles in a 3 M KOH *** delafossite AgFeO_(2)nanoparticles calcined at 100℃(AFO100)exhibited the highest surface area of 28.02 m^(2)·g^(-1)and outstanding electrochemical performance with specific capacitances of 229.71 F·g^(-1)at a current density of 1 A·g^(-1)and 358.32 F·g^(-1)at a scan rate of 2 mV·s^(-1).This sample also demonstrated the capacitance retention of 82.99% after 1000 charge/discharge cycles,along with superior specific power and specific energy values of 797.46 W·kg^(-1)and 72.74Wh·kg^(-1),*** findings indicate that delafossite AgFeO_(2)has great potential as an electrode material for supercapacitor applications.

关键词： nanoparticles delafossite electrochemical properties X-ray absorption spectroscopy co-precipitation supercapacitor

Stereocomplexation and Mechanical Properties of Polylactide-bpoly(propylene glycol)-b-polylactide Blend Films: Effects of Polylactide Block Length and Blend Ratio

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Chinese Journal of Polymer Science 2017年第11期35卷 1391-1401页

作者： Dutchanee Pholharn Onanong Cheerarot Yodthong Baimark Biodegradable Polymers Research Unit Department of Chemistry and Center of Excellence for Innovation in ChemistryFaculty of Science Mahasarakham University

In the present work, poly（propylene glycol）（PPG） was block copolymerized to form polylactide-poly（propylene glycol）-polylactide （PL-PPG-PL） triblock copolymers for preparing flexible stereocomplex PL （scPL） blend films. The scPL blend films were prepared by solution blending of poly（L-lactide）-PPG-poly（L-lactide）（PLL-PPG-PLL） and poly（D-lactide）- PPG-poly（D-lactide）（PDL-PPG-PDL） triblock copolymers before film casting. The influences of PL end-block lengths （2 ×10^4 and 4×10^4 g/tool） and blend ratios （75/25, 50/50 and 25/75 W/W） on the stereocomplexation and mechanical properties of the blend films were evaluated. From DSC and WAXD results, the 50/50 blend films had complete stereocomplexation. Phase separation between the scPL and PPG phases was not observed from their SEM images. The tensile stress and elongation at break increased with the sterecomplex crystallinities and PL end-block lengths. The PPG middle-blocks enhanced elongation at break of the scPL films. The results showed that the PL-PPG-PL triblock structures did not affect stereocomplexation of the PLL/PDL block blending. In conclusion, the phase compatibility and flexibility of the scPL films were improved by PPG block copolymerization.

关键词： Stereocomplex Polylactide Poly(propylene glycol) Block copolymers Mechanical properties

Biodegradation of acrylamide by Enterobacter aerogenes isolated from wastewater in Thailand

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Journal of Environmental Sciences 2011年第3期23卷 396-403页

作者： Kanokhathai Buranasilp Jittima Charoenpanich Biological Science Program and Center of excellence for innovation in Chemistry (PERCH-CIC) Faculty of ScienceBurapha University Department of Biochemistry Faculty of ScienceBurapha University Environmental Science Program and Center of excellence on Environmental health Toxicology and Management of Chemicals (ETM-PERDO)Faculty of ScienceBurapha University

A widespread use of acrylamide, probably a neurotoxicant and carcinogen, in various industrial processes has led to environmental contamination. Fortunately, some microorganisms are able to derive energy from acrylamide. In the present work, we reported the isolation and characterization of a novel acrylamide-degrading bacterium from domestic wastewater in Chonburi, Thailand. The strain grew well in the presence of acrylamide as 0.5% （W/V）, at pH 6.0 to 9,0 and 25℃. Identification based on biochemical characteristics and 16S rRNA gene sequence identified the strain as Enterobacter aerogenes. Degradation of acrylamide to acrylic acid started in the late logarithmic growth phase as a biomass-dependent pattern. Specificity of cell-free supernatant towards amides completely degraded butyramide and urea and 86% of lactamide. Moderate degradation took place in other amides with that by formanaide 〉 benzamide 〉 acetamide 〉 cyanoacetamide 〉 propionamide. No degradation was detected in the reactions of N,N-methylene bisacrylamide, sodium azide, thioacetamide, and iodoacetamide. These results highlighted the potential of this bacterium in the cleanup of acrylamide/amide in the environment.

关键词： acrylamide biodegradation domestic wastewater Enterobacter aerogenes

Transformation of leather waste into microwave-activated and N-doped carbon for Li-S batteries

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新型炭材料(中英文) 2025年

作者： Carolina Pano-Azucena Roberto Rosas-Rangel Miguel Olvera-Sosa David Salvador González-González Rene Rangel-Mendez Luis Felipe Chazaro-Ruiz Miguel Avalos-Borja Javier Antonio Arcibar-Orozco CIATEC.Center for Applied innovation in Competitive Technologies Tecnologico de Monterrey School of Engineering and Sciences Instituto Potosino de Investigación Científica y Tecnológica Universidad Autónoma de Coahuila Facultad de SistemasCiudad Universitaria

The use of carbon from waste biomass has the potential to buffer the drawbacks of Li-S batteries and improve their overall performance. Chrome-Tanned-LeatherShavings(CTLS) are undesirable wastes, highly available for transformation into porous carbon. Microwave activation is an efficient state-of-the-art procedure to obtain unique porous structures and nitrogen incorporation can improve the performance of porous carbons. This study proposes the transformation of CTLS into a microwave activated porous carbon, and then was modified to introduce nitrogen. A microporous activated carbon with a specific surface area of 556 m2g-1 with honeycomb-like structure was obtained. Both urea thermal decomposition and ethanolamine impregnation improves the nitrogen and amine presence of surface groups. However,the results indicated that only urea treatment was effective in improving the initial capacity of the cell(1363 mAhg-1), which is probably linked with the sorption of long-chain polysulfides. This investigation confirms that it is possible to obtain carbon materials from CTLS, for use as sulfur-host cathodes in Li-S batteries, and improve their performance with urea thermal decomposition. Furthermore, a Radial basis function neural network was fitted to provide statistical support to the experimental results. The trained model corroborated the importance of nitrogen content of the carbons in the discharge capacity of the cells.

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Fault Accommodation for a Class of Nonlinear Uncertain Systems With Event-Triggered Input

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IEEE/CAA Journal of Automatica Sinica 2022年第2期9卷 235-245页

作者： Dong Zhao Marios M.Polycarpou IEEE KIOS Research and innovation Center of excellence and the Department of Electrical and Computer EngineeringUniversity of CyprusNicosia 1678Cyprus

The event-triggered fault accommodation problem for a class of nonlinear uncertain systems is considered in this *** control signal transmission from the controller to the system is determined by an event-triggering scheme with relative and constant triggering *** the event-induced control input error and system fault threat,a novel eventtriggered active fault accommodation scheme is designed,which consists of an event-triggered nominal controller for the time period before detecting the occurrence of faults and an adaptive approximation based event-triggered fault accommodation scheme for handling the unknown faults after detecting the occurrence of *** closed-loop stability and inter-event time of the proposed fault accommodation scheme are rigorously *** cases for the fault accommodation design under constant triggering threshold are also *** example is employed to illustrate the effectiveness of the proposed fault accommodation scheme.

关键词： Adaptive control event-triggered control fault accommodation neural networks nonlinear systems