140 research outputs found
On designing hardware accelerator-based systems: interfaces, taxes and benefits
Complementary Metal Oxide Semiconductor (CMOS) Technology scaling has slowed down. One promising approach to sustain the historic performance improvement of computing systems is to utilize hardware accelerators. Today, many commercial computing systems integrate one or more accelerators, with each accelerator optimized to efficiently execute specific tasks.
Over the years, there has been a substantial amount of research on designing hardware accelerators for machine learning (ML) training and inference tasks. Hardware accelerators are also widely employed to accelerate data privacy and security algorithms. In particular, there is currently a growing interest in the use of hardware accelerators for accelerating homomorphic encryption (HE) based privacy-preserving computing.
While the use of hardware accelerators is promising, a realistic end-to-end evaluation of an accelerator when integrated into the full system often reveals that the benefits of an accelerator are not always as expected. Simply assessing the performance of the accelerated portion of an application, such as the inference kernel in ML applications, during performance analysis can be misleading. When designing an accelerator-based system, it is critical to evaluate the system as a whole and account for all the accelerator taxes.
In the first part of our research, we highlight the need for a holistic, end-to-end analysis of workloads using ML and HE applications. Our evaluation of an ML application for a database management system (DBMS) shows that the benefits of offloading ML inference to accelerators depend on several factors, including backend hardware, model complexity, data size, and the level of integration between the ML inference pipeline and the DBMS. We also found that the end-to-end performance improvement is bottlenecked by data retrieval and pre-processing, as well as inference. Additionally, our evaluation of an HE video encryption application shows that while HE client-side operations, i.e., message-to- ciphertext and ciphertext-to-message conversion operations, are bottlenecked by number theoretic transform (NTT) operations, accelerating NTT in hardware alone is not sufficient to get enough application throughput (frame rate per second) improvement. We need to address all bottlenecks such as error sampling, encryption, and decryption in message-to-ciphertext and ciphertext-to-message conversion pipeline.
In the second part of our research, we address the lack of a scalable evaluation infrastructure for building and evaluating accelerator-based systems. To solve this problem, we propose a robust and scalable software-hardware framework for accelerator evaluation, which uses an open-source RISC-V based System-on-Chip (SoC) design called BlackParrot. This framework can be utilized by accelerator designers and system architects to perform an end-to-end performance analysis of coherent and non-coherent accelerators while carefully accounting for the interaction between the accelerator and the rest of the system.
In the third part of our research, we present RISE, which is a full RISC-V SoC designed to efficiently perform message-to-ciphertext and ciphertext-to-message conversion operations. RISE comprises of a BlackParrot core and an efficient custom-designed accelerator tailored to accelerate end-to-end message-to-ciphertext and ciphertext-to-message conversion operations. Our RTL-based evaluation demonstrates that RISE improves the throughput of the video encryption application by 10x-27x for different frame resolutions
A ANÁLISE DO DISCURSO CRÍTICO DA REPRESENTAÇÃO DE GÊNERO NOS LIVROS DE INGLÊS DE HIGH SCHOOLS IRANIANO: : O MODELO FAIRCLOUGH EM FOCO
The present study adopted an exploratory critical discourse analysis (CDA) approach to examine gender representation in Iranian government mandatory high school ELT textbooks using Fairclough model. Considering the model, female and male characters’ visibility, semantic, domestic, and social roles, activities, and pictorial representations in the textbooks were scrutinized. These factors were described, interpreted, and explained both qualitatively and quantitatively. Additionally, a semi-structured interview was conducted with 30 experienced high school educators and their responses were coded, scrutinized, and interpreted. The findings revealed the permanence of male dominance in the textbooks and that the gender bias in educational materials would have strong socio-cultural effects on students’ mind sets, future careers, and fields of study. The findings highlight the must to address gender inequalities as one of the most crucial socio-cultural concerns of Iran EFL educational textbooks.O presente estudo adotou uma abordagem exploratória de análise crítica do discurso (CDA) para examinar a representação de gênero nos livros didáticos de ELT do ensino médio obrigatório do governo iraniano usando o modelo Fairclough. Considerando o modelo, a visibilidade dos personagens femininos e masculinos, papéis semânticos, domésticos e sociais, atividades e representações pictóricas nos livros didáticos foram escrutinados. Esses fatores foram descritos, interpretados e explicados qualitativa e quantitativamente. Além disso, uma entrevista semiestruturada foi realizada com 30 educadores experientes do ensino médio e suas respostas foram codificadas, examinadas e interpretadas. As descobertas revelaram a permanência do domínio masculino nos livros didáticos e que o viés de gênero nos materiais educacionais teria fortes efeitos socioculturais nas mentalidades dos alunos, futuras carreiras e campos de estudo. As descobertas destacam a necessidade de abordar as desigualdades de gênero como uma das preocupações sócio-culturais mais cruciais dos livros didáticos educacionais de EFL do Irã
The survey of Ultrasound – Electrocoagulation process in removal of Ciprofloxacin from aqueous through central composite design
Background and aims: Presence of antibiotics as emerging pollutants have aroused increasing concerns. The modelling of electrocoagulation process with ultrasound in the removal of Ciprofloxacin in aqueous solutions was aimed in the present study.Materials and Methods: In this study a reactor with 1000 mL volume was used. Copper and iron electrodes were exploited as cathode and anode electrodes. Electrodes were connected to a direct electrical current supply as monopolar. The optimization of pH, current density, initial concentration of CIP and reactiontime were conducted by CCD and finally suitable model was presented. In optimized conditions, the amount of electrode corrosion, COD and TOC removal, changes in the UV-Vis adsorption and FT-IR spectrum was measured. All procedures in study were conducted ethically.Results: Optimum conditions were found to occur at pH, current density, and reaction time of 7. 4, 1.5 In this situation the predicted and.A and 30 min, respectively in 15 mg CIP /L as an initial concentration actual efficiencies were 88.21 and 86.37 %, respectively. Also, a moderate COD and TOC removal, about64 and 51 percent was achieved, respectively. Result of FT-IR analysis showed considerable changes in functional groups during removal process. Synergist effect of US in electrocoagulation process was estimated to be only 14 percent.Conclusion: The results indicate that the proposed process have a good efficiency in CIP removal. It is possible to decrease the concentrations of similar pollutants before their discharge to the environment by the use of this method.Keywords: Ultrasound – Electrocoagulation process, modelling, Ciprofloxacin, Central composite design, aqueou
Transcranial Direct Current Stimulation Combining Mindfulness Based Relapse Prevention for Smoking Cessation: A Case Report
Previous electroencephalography (EEG) researches have shown significant differences in terms of abnormal brain activity among smokers and non-smokers. Typically, EEG analysis showed decreased slow waves and increased fast waves in people with nicotine consumption. The present study tested a transcranial direct current stimulation (tDCS) technique combined with Mindfulness-Based Relapse Prevention (MBRP) to reduce nicotine cravings. Specifically, cathodal tDCS over Left Prefrontal Cortex (PFC), as well as anodal stimulation over the right central zone, tested. An 18-year-old right-handed male with almost three years of smoking participated. He had no anti-tobacco medical prescription. The participant received twelve sessions of tDCS treatment (two times a week). Anodal stimulation (1.5 mA, 15 min) performed on C3 (LORETA source localization) and cathodal stimulation on FP2. Also, the participant received 30-minute MBRP-based psychotherapy sessions in order to ameliorate aggression, stress, and craving. Clinical evaluations, Buss-Perry Aggression Questionnaire (AGQ), Fagerstrom Test for Nicotine Dependence (FTND), Perceived Stress Scale (Cohen, Kamarck, & Mermelstein, 1994), and daily checklist for the number of smoked cigarettes administered along with Carbon monoxide (CO) levels. Also, subjective measures of craving intensity between zero and ten measured after treatment and 3-month follow-up. After treatment, the participant showed a substantial reduction in all clinical tests, and the number of cigarettes decreased from 30 to 2 a day. From a psycho neurotherapeutic perspective, the present study provides preliminary indications for a novel and efficient treatment of smoking during adolescence. Further studies are needed to determine generalizability and overall efficiency
RISE: RISC-V SoC for En/decryption Acceleration on the Edge for Homomorphic Encryption
Today edge devices commonly connect to the cloud to use its storage and
compute capabilities. This leads to security and privacy concerns about user
data. Homomorphic Encryption (HE) is a promising solution to address the data
privacy problem as it allows arbitrarily complex computations on encrypted data
without ever needing to decrypt it. While there has been a lot of work on
accelerating HE computations in the cloud, little attention has been paid to
the message-to-ciphertext and ciphertext-to-message conversion operations on
the edge. In this work, we profile the edge-side conversion operations, and our
analysis shows that during conversion error sampling, encryption, and
decryption operations are the bottlenecks. To overcome these bottlenecks, we
present RISE, an area and energy-efficient RISC-V SoC. RISE leverages an
efficient and lightweight pseudo-random number generator core and combines it
with fast sampling techniques to accelerate the error sampling operations. To
accelerate the encryption and decryption operations, RISE uses scalable,
data-level parallelism to implement the number theoretic transform operation,
the main bottleneck within the encryption and decryption operations. In
addition, RISE saves area by implementing a unified en/decryption datapath, and
efficiently exploits techniques like memory reuse and data reordering to
utilize a minimal amount of on-chip memory. We evaluate RISE using a complete
RTL design containing a RISC-V processor interfaced with our accelerator. Our
analysis reveals that for message-to-ciphertext conversion and
ciphertext-to-message conversion, using RISE leads up to 6191.19X and 2481.44X
more energy-efficient solution, respectively, than when using just the RISC-V
processor
Drug Resistance of Acinetobacter in Selected Hospitals
Background: Nowadays, nosocomial infection with multidrug-resistant Acinetobacter is an important problem in the world, which is facing wide spectrum antibiotics and hence has become resistant.Materials and Methods: In this study, positive cultures of Acinetobacter from one hundred clinical samples in seven hospitals from Tehran during 2012-2013 were collected for checking antibiotic susceptibility. Samples test with Ceftazidim, Cefepime, Amikacine and Imipenem by E-test and for Tazocin, Colistin and Tigecycline was performed with disk diffusion method.Results: For Colistin 10 samples, and for Tazocin, 40 samples were performed by E-test method. Then boumannii species of bacteria and non-baumannii Acinetobacter were separated by PCR and antibiotic susceptibility testing was performed on them. 89% of Acinetobacter samples were boumannii species, which was isolated from respiratory secretions at ICU.Conclusion: Boumannii and non-boumannii species of bacteria with a high percentage were resistant to Ceftazidim, Amikacine, Cefepime, Tazocin and Imipenem. All baumannii and non-boumannii Acinetobacter were sensitive to Colistin, were only 75% sensitive to Tigecycline, which is a new glycylcycline. Colistin and Tazocin results in samples limited to the E-test method were similar with disk diffusion
The effect of dialectical behavioral therapy on craving and depression in methadone patients
Background: Methadone maintenance treatment (MMT) is a common medication for opioid dependence disorder. Despite the positive results, this therapy has many physical and psychological effects. The aim of this study was to determine the effectiveness of a dialectical behavioral therapy (DBT) on craving and depression in people under the methadone maintenance therapy. Materials and Methods: This is a randomized, controlled clinical trial with intervention (DBT) and control (MMT) groups. Initial diagnostic evaluations were performed by psychiatrist and clinician at a clinical interview. Fifty men referred to methadone treatment clinic were randomly assigned to the two groups (intervention and control). Data were collected through demographic information questionnaire, craving scale, depression questionnaire, treatment validity questionnaire, and treatment alliance questionnaire for pre-test, post-test and follow up. Results: The results showed that the scores of the intervention group were significantly reduced in comparison with the control group in craving and depression after 4 months of intervention and 2 months follow-up (P<0.01). Conclusion: The combination of the methadone therapy and dialectical behavior therapy can be useful in reducing craving and psychological problems of opiate dependent people. Considering the emphasis on a dialectical behavioral therapy on emotional regulation as the main mechanism for change, this treatment can be a useful therapy for other psychological disorders that are involved with emotional problems
بررسی فرایند سونو- الکتروکواگولاسیون در حذف سیپروفلوکساسین از محیط های آبی با طراحی ترکیبی مرکزی
Background and aims: Presence of antibiotics as emerging pollutants have aroused increasing concerns. The modelling of electrocoagulation process with ultrasound in the removal of Ciprofloxacin in aqueous solutions was aimed in the present study.Materials and Methods: In this study a reactor with 1000 mL volume was used. Copper and iron electrodes were exploited as cathode and anode electrodes. Electrodes were connected to a direct electrical current supply as monopolar. The optimization of pH, current density, initial concentration of CIP and reactiontime were conducted by CCD and finally suitable model was presented. In optimized conditions, the amount of electrode corrosion, COD and TOC removal, changes in the UV-Vis adsorption and FT-IR spectrum was measured. All procedures in study were conducted ethically.Results: Optimum conditions were found to occur at pH, current density, and reaction time of 7. 4, 1.5 In this situation the predicted and.A and 30 min, respectively in 15 mg CIP /L as an initial concentration actual efficiencies were 88.21 and 86.37 %, respectively. Also, a moderate COD and TOC removal, about64 and 51 percent was achieved, respectively. Result of FT-IR analysis showed considerable changes in functional groups during removal process. Synergist effect of US in electrocoagulation process was estimated to be only 14 percent.Conclusion: The results indicate that the proposed process have a good efficiency in CIP removal. It is possible to decrease the concentrations of similar pollutants before their discharge to the environment by the use of this method.زمینه و اهدف: حضور ترکیبات آنتیبیوتیک بعنوان آلایندههای نوظهور باعث افزایش نگرانی شده است. هدف از این مطالعه، مدلسازی فرایند الکتروکواگولاسیون در حضور امواج التراسوند در حذف سیپروفلوکساسین از محیط آبی است.
مواد و روشها: در این مطالعه، یک راکتور به حجم یک لیتر مورد استفاده قرار گرفت. الکترود مس بعنوان کاتد و الکترود آهن بعنوان آند استفاده شد. اتصال الکترودها به دستگاه تامین کننده جریان الکتریکی مستقیم بصورت تک قطبی پیوسته بود. بهینهسازی پارامترهای pH، جریان الکتریکی، غلظت اولیه سیپروفلوکساسین و زمان واکنش با استفاده از طراحی ترکیبی مرکزی انجام شد و مدل مناسب ارایه شد. در شرایط بهینه فرایند، میزان خوردگی الکترودها، میزان کاهش COD و TOC، تغییرات ایجاد شده در منحنی طیف UV-Vis و طیف سنجی FT-IR اندازهگیری شد. در کلیه مراحل انجام پژوهش، موازین اخلاقی، مراعات گردید.
یافتهها: شرایط مناسب فرایند برای حذف آنتیبیوتیک شامل pH برابر 7/4، جریان الکتریکی 1/5 آمپر، زمان واکنش برابر 30 دقیقه در غلظت اولیه 15 میلیگرم در لیتر بدست آمد. در این حالت بازده تئوریکی و عملی به ترتیب برابر 88/21و 86/37درصد بدست آمد. کاهش COD و TOC به ترتیب برابر 64 و 51 درصد بود. نتایج FT-IR نشان دهنده تغییرات گسترده گروه های عاملی در طی فرایند بود. خاصیت همافزایی حضور امواج التراسوند با توان 350 وات و 40 کیلوهرتز در فرایند الکتروکواگولاسیون 14 درصد تعیین شد.
نتیجه گیری: نتایج بیانگر کارایی نسبتا مناسب فرایند سونوالکتروکواگولاسیون در کاهش میزان سیپروفلوکساسین بود. با استفاده از این روش میتوان پساب حاوی این آلاینده را پس از کاهش غلظت، به محیط دفع نمود.
کلید واژهها: فرایند سونوالکتروکواگولاسیون، مدلسازی، سیپروفلوکساسین، طراحی ترکیبی مرکزی، محیطهای آب
Prevalence of blaCTX-M gene in multi-resistant Escherichia coli isolated from Urinary Tract Infections, Tehran, Iran
Background:The emergence and increase in the incidence of Extended-spectrum beta lactamase (ESBL) producing Escherichia coli has become an emerging challenge especially in hospitalized patients with UTI. The aim of the present study was to survey the frequency of bla CTX-M genotype in ESBL producing E. coli isolated from hospitalized patients with UTI and determination of their antibiotic resistance pattern.Material and methodsA total of 135 E. coli isolates were collected from isolated from patients with UTI. The isolates were subjected to confirmatory phenotype tests for the presence of ESBL. 75 E. coli isolates were confirmed as ESBL-positive by means of the Double disc synergy test. In vitro susceptibility of ESBL isolates to 15 antimicrobial agents amoxicillin, penicillin, ceftazidime, cefotaxime, cefoxitin, ceftriaxone, cefixime, cephalexin, co-trimoxazole, gentamicin, nalidixic acid, ciprofloxacin, nitrofourantoin, amikacin and imipenem was performed by Kirby-Bauer’s Disk diffusion method according to Clinical and Laboratory Standards Institute (CLSI, 2012) guideline. PCR method was used to identify bla CTX-M gene in 75 ESBL positive strains.Results:PCR and sequence analysis showed that 75 (55.5%) isolates produced bla CTX-M genes. In vitro susceptibility of ESBL producing E. coli showed that all of them were resistant to amoxicillin and penicillin and The rates of resistance to the majority of tested antibiotics varied between 61% to 100 %, with the exception of amikacin (14.7%) and imipenem (2.7%). Our results showed that the frequency of bla CTX-M was strikingly high (93.3%).Conclusion:These data confirmed that the frequency of bla CTX-M genes were high among E. coli isolated from patients with UTI. The trend of multidrug-resistant profile has been associated with bla CTX-M gene is alarming. Therefore, it is very important to establish a routine screening of ESBL in clinical isolates to prevent dissemination of resistant isolates in health care settings
Characterization of coagulase-negative staphylococci isolated from hospitalized patients in Tehran, Iran
Coagulase-negative staphylococci (CNS) are a main cause of nosocomial infection. The main purpose of this study was to determination of frequency of CNS isolates in in hospitalized patients and their susceptibility pattern to antimicrobial agents. During 11 month study, 65 CNS clinical isolates were recovered from hospitalized patients in different wards of hospital. In vitro susceptibility of isolates to 12 antimicrobial agents Penicillin; Ampicilin; Cephalothin; Cefoxitin; linezolid; Nitofurantoin; Erythromycin; Norfloxacin; Gentamicin; Vancomycin; Chloramphenicol and Oxacillin was performed by Kirby-Bauer’s Disk diffusion method according to Clinical and Laboratory Standards Institute (CLSI) criteria. Out of 1875 samples of hospitalized patients 65(3.47%) patients were infected with CNS. Twenty one (32.3 %) were isolated from the urine samples, 17(26.1%) from sputum, 15(23.1%) from pus samples, 8(12.3 %) from ear swabs, 3(4.7%) from fluid and 1(1.5%) from blood sample. All of CNS isolates were sensitive to nitrofurantoin. The rates of resistance to the majority of antibiotics tested varied between 4.5% and 100 %. The rate of resistance to beta lactam antibiotics, Chloramphenicol, erythromycin, gentamycin was high (more than 70%). The most of isolates remained susceptible to linezolid, and nitofurantoin. All of isolates were susceptible to vancomycin. Multi-drug resistant CNS with reduced susceptibility to linezolid and nitrofurantoin are emerging pathogens of clinical concern. Monitoring of antibiotic resistance with attention to multi-resistant profile and aware to practitioners in the field is necessary
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