H-SIMD machine : configurable parallel computing for data-intensive applications

This dissertation presents a hierarchical single-instruction multiple-data (H-SLMD) configurable computing architecture to facilitate the efficient execution of data-intensive applications on field-programmable gate arrays (FPGAs). H-SIMD targets data-intensive applications for FPGA-based system designs. The H-SIMD machine is associated with a hierarchical instruction set architecture (HISA) which is developed for each application. The main objectives of this work are to facilitate ease of program development and high performance through ease of scheduling operations and overlapping communications with computations. The H-SIMD machine is composed of the host, FPGA and nano-processor layers. They execute host SIMD instructions (HSIs), FPGA SIMD instructions (FSIs) and nano-processor instructions (NPLs), respectively. A distinction between communication and computation instructions is intended for all the HISA layers. The H-SIMD machine also employs a memory switching scheme to bridge the omnipresent large bandwidth gaps in configurable systems. To showcase the proposed high-performance approach, the conditions to fully overlap communications with computations are investigated for important applications. The building blocks in the H-SLMD machine, such as high-performance and area-efficient register files, are presented in detail. The H-SLMD machine hierarchy is implemented on a host Dell workstation and the Annapolis Wildstar II FPGA board. Significant speedups have been achieved for matrix multiplication (MM), 2-dimensional discrete cosine transform (2D DCT) and 2-dimensional fast Fourier transform (2D FFT) which are used widely in science and engineering. In another FPGA-based programming paradigm, a high-level language (here ANSI C) can be used to program the FPGAs in a mode similar to that of the H-SIMD machine in terms of trying to minimize the effect of overheads. More specifically, a multi-threaded overlapping scheme is proposed to reduce as much as possible, or even completely hide, runtime FPGA reconfiguration overheads. Nevertheless, although the HLL-enabled reconfigurable machine allows software developers to customize FPGA functions easily, special architecture techniques are needed to achieve high-performance without significant penalty on area and clock frequency. Two important high-performance applications, matrix multiplication and image edge detection, are tested on the SRC-6 reconfigurable machine. The implemented algorithms are able to exploit the available data parallelism with independent functional units and application-specific cache support. Relevant performance and design tradeoffs are analyzed

CYP2J3 Gene Delivery Reduces Insulin Resistance via Upregulation of eNOS in Fructose-treated Rats

Accumulating evidence suggests that cytochrome P450 (CYP) epoxygenases metabolize arachidonic acid into epoxyeicosatrienoic acids (EETs) which play important roles in various pathophysiological processes. Interestingly, CYP-derived eicosanoids are vasodilatory, at least in part through their ability to activate eNOS and subsequent NO release. This study investigated the roles of eNOS in CYP2J3 gene delivery reducing blood pressure and improving insulin resistance in fructose-treated rats. CYP2J3 overexpression in vivo increased EET generation, reduced blood pressure and reversed insulin resistance as determined by insulin resistance index (HOMA-IR). Furthermore, administration of eNOS inhibitor L-NMMA significantly and partially abolished the beneficial effects of CYP2J3 gene delivery on hypertension and insulin resistance induced by fructose intake, and possible mechanism is associated with increased ET-1, ETA-receptor mRNA expression and reduced sensitivity of insulin to peripheral tissues and organs characterized by reduced activity of IRS-1/PI3K/AKT and AMPK signalling pathways. These data provide direct evidence that CYP2J3-derived EETs may alleviate insulin resistance at least in part through upregulated eNOS expression

Cytochrome P450 2J2 is protective against global cerebral ischemia in transgenic mice

Cytochrome P450 epoxygenase metabolites of arachidonic acid (EETs) have multiple cardiovascular effects, including reduction of blood pressure, protection against myocardial ischemia-reperfusion injury, and attenuation of endothelial inflammation and apoptosis. The present study was aimed to determine potential neuroprotective roles for EETs in cerebral ischemia

H-simd machine: Configurable parallel computing for matrix multiplication

FPGAs (Field-Programmable Gate Arrays) are often used as coprocessors to boost the performance of dataintensive applications [1, 2]. However, mapping algorithms onto multimillion-gate FPGAs is time consuming and remains a challenge in configurable system design. The communication overhead between the host workstation and the FPGAs is also significant. To address these problems, we propose in this paper the FPGA-based Hierarchical-SIMD (H-SIMD) machine with its codesign of the Hierarchical Instruction Set Architecture (HISA). At each level, HISA instructions are classified into communication instructions or computation instructions. The former are executed by the local controller while the latter are issued to the lower level for execution. Additionally, by using a memory switching scheme and the high-level HISA set to partition the application into coarse-grain tasks, the host-FPGA communication overhead can be hidden. We enlist matrix multiplication (MM) to test the effectiveness of H-SIMD. The test results show sustained high performance. 1

The impact of heatwaves on human perceived thermal comfort and thermal resilience potential in urban public open spaces

Climate change increases the likelihood of heatwave events, causing human thermal discomfort and even mortality. However, it is not clear to what extent humans with long-term and short-term experience of hot-summer exposure can adapt to thermal comfort in urban public open spaces when both experience their heatwave periods. Therefore, this study aims to investigate outdoor perceived thermal comfort in urban public open spaces during heatwave periods between two groups of people who have long-term and short-term experience of hot-summer exposure. Field surveys were conducted in public squares and parks during the heatwaves in Chongqing, China and Reading, the UK. Chongqing is known as a ‘furnace city’ and people have been living in a hot summer for a long time, while in Reading the summer is warm and people unusually experience the heatwave. The main results show that Chongqing respondents living in a hot climate for a longer period can endure more heat than Reading respondents during the heatwaves, indicating that Chongqing respondents have more thermal resilience. Besides, different behavioural adaptation measures show that people are active participants to choose their thermal preferences, rather than passive recipients of the thermal environments. The research implication contributes that protective measures against heatwaves need to be taken for pedestrians, including more shaded places with efficient ventilation design for sheltering and handy facilities such as drinking fountains and water spray. The research has novelty in deepening the dynamic theory of human thermal comfort and providing empirical evidence of thermal adaptation in extreme-high temperature events

A method of predicting the dynamic thermal sensation under varying outdoor heat stress conditions in summer

Heat stress events in urban areas are increasing as a result of global warming and urban heat islands. In response to heat stress, outdoor activators naturally often move themselves to a less hot place. An understanding of human physiological responses in dynamic outdoor thermal environments is desired. This study aims to reveal the dynamic physiological adjustment and thermal perception response characteristics under varying outdoor heat stress conditions. A robust model for predicting dynamic thermal sensation outdoors has been developed. Experiments involving heat stress changes in a hot summer were conducted with 25 subjects. Three categories of data were collected including meteorological data, physiological parameters, and thermal perception. The results showed that lower-arm skin temperature (Tlowerarm) is more sensitive to changes in the outdoor thermal environment, and correlates closely with the thermal sensation vote (TSV). For a better practical application, based on the strong linear relationship between Tlowerarm and Tty, the new dynamic outdoor thermal sensation model has been developed involving two parameters: Tlowerarm and ΔTlowerarm/Δt (the change rate of Tlowerarm). The validity of the model in transient outdoor conditions was verified. The algorithm can be integrated into a wearable armband to predict practical thermal sensation responses. This contribution will advance technologies based on the scientific findings to provide alert services to support human health and wellbeing, consequently increasing urban resilience and sustainability

Quality Evaluation Approach for Prefabricated Buildings Using Ant Colony Algorithm and Simulated Annealing Algorithm to Optimize the Projection Pursuit Model

There are problems with an inadequate quality assurance system and non-standard construction organization and administration while creating prefabricated buildings. There are currently fewer quality assessments employing prefabricated component combinations as the research focus, and the quality evaluation methodology is more subjective. We propose a method for evaluating the quality of prefabricated buildings using an ant colony algorithm and a simulated annealing algorithm to optimize the projection pursuit model: firstly, create a prefabricated building quality index system; secondly, questionnaires were distributed, tested for reliability and validity to avoid the influence of questionnaire subjectivity on the results, and structural equation modeling was used to calculate the weights of the quality influencing factors; thirdly, quantify the quality factors of prefabricated components by using the quality function development method, and construct a quality optimization model for the prefabricated component combinations; fourthly, use the ant colony algorithm to solve the quality optimization model to obtain a set of prefabricated component combinations to satisfy the quality requirements; and lastly, use a simulated annealing to optimize the projected pursuit method for evaluating the quality of prefabricated component combination solutions. The results show that (1) The use of optimization algorithms can successfully avoid the issue of a more subjective evaluation approach and increase the efficiency and accuracy of evaluation. (2) Residential Comfort (RC), Usage Durability (UD) and Structural Reliability (SR) have a substantially negative association, but Residential Comfort (RC) and Installation Stability (IS) have strong positive correlations. (3) Based on the magnitude of the vector of the ideal projection direction of the quality indicators, it was determined that the Installation Stability (IS) indicator had the greatest influence on the evaluation of the program, and the Structural Reliability (SR) indicator had the least influence on the program

Downregulation of lncRNA NEAT1 interacts with miR-374b-5p/PGAP1 axis to aggravate the development of osteoarthritis

Abstract Background Osteoarthritis (OA), characterized by inflammation and articular cartilage degradation, is a prevalent arthritis among geriatric population. This paper was to scrutinize the novel mechanism of long noncoding RNA (lncRNA) NEAT1 in OA etiology. Methods A total of 10 OA patients and 10 normal individuals was included in this study. Cell model of OA was built in human normal chondrocytes induced by lipopolysaccharide (LPS). An OA Wistar rat model was established through intra-articular injection of L-cysteine and papain mixtures (proportion at 1:2) into the right knee. Quantitative reverse transcription-polymerase chain reaction was employed to ascertain the expression levels of NEAT1, microRNA (miR)-374b-5p and post-GPI attachment to protein 1 (PGAP1), while dual-luciferase reporter experiments were used for the validation of target relationship among them. Cell cycle and apoptosis were calculated by flow cytometry analysis. CCK-8 assay was done to evaluate the proliferative potentials of chondrocytes. The levels of cell cycle-related proteins (Cyclin A1, Cyclin B1 and Cyclin D2) and pro-apoptotic proteins (Caspase3 and Caspase9) were measured by western blotting. Tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and IL-6 levels were determined via ELISA. Hematoxylin & eosin (HE) Staining was used for pathological examination in OA rats. Results Pronounced downregulation of NEAT1 and PGAP1 and high amounts of miR-374b-5p were identified in OA patients, LPS-induced chondrocytes and OA rats. NEAT1 targeted miR-374b-5p to control PGAP1 expression. Loss of NEAT1 or upregulation of miR-374b-5p dramatically accelerated apoptosis, led to the G1/S arrest and promoted the secretion of inflammatory cytokines in LPS-induced chondrocytes, while ectopic expression of PGAP1 exhibited the opposite influences on chondrocytes. Additionally, we further indicated that upregulation of miR-374b-5p attenuated the effects of PGAP1 overexpression on LPS-induced chondrocytes. Conclusions Reduced NEAT1 induces the development of OA via miR-374b-5p/PGAP1 pathway. This suggests that the regulatory axis NEAT1/miR-374b-5p/PGAP1 is a novel and prospective target for OA treatment