357 research outputs found

    A\c{C}AI: Ascent Similarity Caching with Approximate Indexes

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    Similarity search is a key operation in multimedia retrieval systems and recommender systems, and it will play an important role also for future machine learning and augmented reality applications. When these systems need to serve large objects with tight delay constraints, edge servers close to the end-user can operate as similarity caches to speed up the retrieval. In this paper we present A\c{C}AI, a new similarity caching policy which improves on the state of the art by using (i) an (approximate) index for the whole catalog to decide which objects to serve locally and which to retrieve from the remote server, and (ii) a mirror ascent algorithm to update the set of local objects with strong guarantees even when the request process does not exhibit any statistical regularity

    Static and Dynamic Behavior of Composite Concrete-Based Beams with Embedded Polymer/FRP Components

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    AbstractRecently, the seismic reassessment led to justify the behavior of concrete structures and to dispose members able to dissipate energy through a ductile behavior. In this respect, the present work aims to propose a new concrete-composite beam design, which allows the resumption of the shearing action under static and dynamic loads. The proposed design consists to incorporate in the tensile zone of the beam a rectangular polymer member wrapped by FRP, in order to prevent lateral deformation and to significantly enhance bending and shear strengths. A detailed experimental program is carried out on simply supported composite beams under typical four-point bending loads. Experiments are completed by nonlinear finite element modeling based on a local approach to simulate the real behavior of such elements and to allow a better understanding of experimental observations. The average test and numerical results in terms of overall and observed response are emphasized and discussed. In addition, the influence of the shear strength generated by static and dynamic loads as well as the adequate parameters improving the flexural capacity and ductility are assessed to highlight the mechanical performances of the new beam compared to classical RC beams

    Online Submodular Maximization via Online Convex Optimization

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    We study monotone submodular maximization under general matroid constraints in the online setting. We prove that online optimization of a large class of submodular functions, namely, weighted threshold potential functions, reduces to online convex optimization (OCO). This is precisely because functions in this class admit a concave relaxation; as a result, OCO policies, coupled with an appropriate rounding scheme, can be used to achieve sublinear regret in the combinatorial setting. We show that our reduction extends to many different versions of the online learning problem, including the dynamic regret, bandit, and optimistic-learning settings.Comment: Under revie

    Towards Inference Delivery Networks: Distributing Machine Learning with Optimality Guarantees

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    An increasing number of applications rely on complex inference tasks that are based on machine learning (ML). Currently, there are two options to run such tasks: either they are served directly by the end device (e.g., smartphones, IoT equipment, smart vehicles), or offloaded to a remote cloud. Both options may be unsatisfactory for many applications: local models may have inadequate accuracy, while the cloud may fail to meet delay constraints. In this paper, we present the novel idea of \emph{inference delivery networks} (IDNs), networks of computing nodes that coordinate to satisfy ML inference requests achieving the best trade-off between latency and accuracy. IDNs bridge the dichotomy between device and cloud execution by integrating inference delivery at the various tiers of the infrastructure continuum (access, edge, regional data center, cloud). We propose a distributed dynamic policy for ML model allocation in an IDN by which each node dynamically updates its local set of inference models based on requests observed during the recent past plus limited information exchange with its neighboring nodes. Our policy offers strong performance guarantees in an adversarial setting and shows improvements over greedy heuristics with similar complexity in realistic scenarios

    Comprehensive Assessment of Toxicity in ChatGPT

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    Moderating offensive, hateful, and toxic language has always been an important but challenging topic in the domain of safe use in NLP. The emerging large language models (LLMs), such as ChatGPT, can potentially further accentuate this threat. Previous works have discovered that ChatGPT can generate toxic responses using carefully crafted inputs. However, limited research has been done to systematically examine when ChatGPT generates toxic responses. In this paper, we comprehensively evaluate the toxicity in ChatGPT by utilizing instruction-tuning datasets that closely align with real-world scenarios. Our results show that ChatGPT's toxicity varies based on different properties and settings of the prompts, including tasks, domains, length, and languages. Notably, prompts in creative writing tasks can be 2x more likely than others to elicit toxic responses. Prompting in German and Portuguese can also double the response toxicity. Additionally, we discover that certain deliberately toxic prompts, designed in earlier studies, no longer yield harmful responses. We hope our discoveries can guide model developers to better regulate these AI systems and the users to avoid undesirable outputs

    THE REALITY OF THE ALGERIAN COURT TO SETTLE SPORTS DISPUTES UNDER SPORTS PROFESSIONALISM

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    تهدف هذه الدراسة إلى توضيح الدور الذي تقوم به المحكمة الجزائرية لتسوية النزاعات الرياضية كهيئة قانونية متخصصة في تسوية نزاعات الحركة الرياضية الوطنية، ومن بين هذه الأهداف نذكر :تسليط الضوء على المحكمة الجزائرية لتسوية النزاعات الرياضية كهيئة قانونية، مستقلة ومتخصصة والتعريف بها وبغرفها، وابراز الدور الذي تلعبه المحكمة الجزائرية لتسوية النزاعات الرياضية في تطبيق المنظومة الاحترافية .وتسليط الضوء على طبيعة القضايا المطروحة أمام المحكمة الجزائرية لتسوية النزاعات الرياضية وطرق معالجتها لهذه القضايا، وابراز القوة القانونية للأحكام و القرارات التي تصدرها المحكمة الجزائرية لتسوية النزاعات الرياضية كقطب متخصص. وتحديد مفهوم النزاع الرياضي وآليات تسويته على مستوى محكمة التحكيم الرياضي الجزائرية، الإطلاع على محتوى القوانين والقواعد الإجرائية التي تنظم سير محكمة التحكيم الرياضي الجزائرية. استخدم الباحثون المنهج الوصفي وتم جمع البيانات من خلال الاستبيان والمقابلة. وأبرزت النتائج المحكمة الجزائرية لتسوية النزاعات الرياضية تتمتع بالاستقلالية، وأن المحكمة الجزائرية لتسوية النزاعات الرياضية تلعب دوراً ايجابياً في تسوية نزاعات الناتجة عن تطبيق المنظومة الاحترافية في الجزائرThe aim of this study was to clarify the role of Algerian court as a professional community, some of these goals are to solve problems by using law, it has dependency, specialist, and identify the style of problems that solve, highlight the nature of the cases in front of the Algerian court to settle sports disputes, the legal force of judgments and decisions as a specialized pole, and defining the concepts of mathematical conflict and mechanism for setting it. To do those researchers used the description curriculum with questioner & interview Main results were that the court is independent, has a positive role at solving sports problems related to professionalism system in Algeri

    Cloning and characterization of microRNAs from rainbow trout (Oncorhynchus mykiss): Their expression during early embryonic development

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    <p>Abstract</p> <p>Background</p> <p>Current literature and our previous results on expression patterns of oocyte-specific genes and transcription factors suggest a global but highly regulated maternal mRNA degradation at the time of embryonic genome activation (EGA). MicroRNAs (miRNAs) are small, non-coding regulatory RNAs (19–23 nucleotides) that regulate gene expression by guiding target mRNA cleavage or translational inhibition. These regulatory RNAs are potentially involved in the degradation of maternally inherited mRNAs during early embryogenesis.</p> <p>Results</p> <p>To identify miRNAs that might be important for early embryogenesis in rainbow trout, we constructed a miRNA library from a pool of unfertilized eggs and early stage embryos. Sequence analysis of random clones from the library identified 14 miRNAs, 4 of which are novel to rainbow trout. Real-time PCR was used to measure the expression of all cloned miRNAs during embryonic development. Four distinct expression patterns were observed and some miRNAs showed up-regulated expression during EGA. Analysis of tissue distribution of these miRNAs showed that some are present ubiquitously, while others are differentially expressed among different tissues. We also analyzed the expression patterns of Dicer, the enzyme required for the processing of miRNAs and Stat3, a transcription factor involved in activating the transcription of miR-21. Dicer is abundantly expressed during EGA and Stat3 is up-regulated before the onset of EGA.</p> <p>Conclusion</p> <p>This study led to the discovery of 14 rainbow trout miRNAs. Our data support the notion that Dicer processes miRNAs and Stat3 induces expression of miR-21 and possibly other miRNAs during EGA. These miRNAs in turn guide maternal mRNAs for degradation, which is required for normal embryonic development.</p

    Improvement of renal oxidative stress markers after ozone administration in diabetic nephropathy in rats

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    <p>Abstract</p> <p>Background</p> <p>Several complications of diabetes mellitus (DM) e.g. nephropathy (DN) have been linked to oxidative stress. Ozone, by means of oxidative preconditioning, may exert its protective effects on DN.</p> <p>Aim</p> <p>The aim of the present work is to study the possible role of ozone therapy in ameliorating oxidative stress and inducing renal antioxidant defence in streptozotocin (STZ)-induced diabetic rats.</p> <p>Methods</p> <p>Six groups (n = 10) of male Sprague Dawley rats were used as follows: Group C: Control group. Group O: Ozone group, in which animals received ozone intraperitoneally (i.p.) (1.1 mg/kg). Group D: Diabetic group, in which DM was induced by single i.p. injections of streptozotocin (STZ). Group DI: Similar to group D but animals also received subcutaneous (SC) insulin (0.75 IU/100 gm BW.). Group DO: In which diabetic rats received the same dose of ozone, 48 h after induction of diabetes. Group DIO, in which diabetic rats received the same doses of insulin and ozone, respectively. All animals received daily treatment for six weeks. At the end of the study period (6 weeks), blood pressure, blood glycosylated hemoglobin (HbA<sub>1c</sub>), serum creatinine, blood urea nitrogen (BUN), kidney tissue levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxide (GPx), aldose reductase (AR) activities and malondialdehyde (MDA) concentration were measured.</p> <p>Results</p> <p>Induction of DM in rats significantly elevated blood pressure, HbA<sub>1c</sub>, BUN, creatinine and renal tissue levels of MDA and AR while significantly reducing SOD, CAT and GPx activities. Either Insulin or ozone therapy significantly reversed the effects of DM on all parameters; in combination (DIO group), they caused significant improvements in all parameters in comparison to each alone.</p> <p>Conclusions</p> <p>Ozone administration in conjunction with insulin in DM rats reduces oxidative stress markers and improves renal antioxidant enzyme activity which highlights its potential uses in the regimen for treatment of diabetic patients.</p

    Neglected Tropical Diseases of the Middle East and North Africa: Review of Their Prevalence, Distribution, and Opportunities for Control

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    The neglected tropical diseases (NTDs) are highly endemic but patchily distributed among the 20 countries and almost 400 million people of the Middle East and North Africa (MENA) region, and disproportionately affect an estimated 65 million people living on less than US$2 per day. Egypt has the largest number of people living in poverty of any MENA nation, while Yemen has the highest prevalence of people living in poverty. These two nations stand out for having suffered the highest rates of many NTDs, including the soil-transmitted nematode infections, filarial infections, schistosomiasis, fascioliasis, leprosy, and trachoma, although they should be recognized for recent measures aimed at NTD control. Leishmaniasis, especially cutaneous leishmaniasis, is endemic in Syria, Iran, Iraq, Libya, Morocco, and elsewhere in the region. Both zoonotic (Leishmania major) and anthroponotic (Leishmania tropica) forms are endemic in MENA in rural arid regions and urban regions, respectively. Other endemic zoonotic NTDs include cystic echinococcosis, fascioliasis, and brucellosis. Dengue is endemic in Saudi Arabia, where Rift Valley fever and Alkhurma hemorrhagic fever have also emerged. Great strides have been made towards elimination of several endemic NTDs, including lymphatic filariasis in Egypt and Yemen; schistosomiasis in Iran, Morocco, and Oman; and trachoma in Morocco, Algeria, Iran, Libya, Oman, Saudi Arabia, Tunisia, and the United Arab Emirates. A particularly noteworthy achievement is the long battle waged against schistosomiasis in Egypt, where prevalence has been brought down by regular praziquantel treatment. Conflict and human and animal migrations are key social determinants in preventing the control or elimination of NTDs in the MENA, while local political will, strengthened international and intersectoral cooperative efforts for surveillance, mass drug administration, and vaccination are essential for elimination

    Anisotropic nanomaterials: structure, growth, assembly, and functions

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    Comprehensive knowledge over the shape of nanomaterials is a critical factor in designing devices with desired functions. Due to this reason, systematic efforts have been made to synthesize materials of diverse shape in the nanoscale regime. Anisotropic nanomaterials are a class of materials in which their properties are direction-dependent and more than one structural parameter is needed to describe them. Their unique and fine-tuned physical and chemical properties make them ideal candidates for devising new applications. In addition, the assembly of ordered one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) arrays of anisotropic nanoparticles brings novel properties into the resulting system, which would be entirely different from the properties of individual nanoparticles. This review presents an overview of current research in the area of anisotropic nanomaterials in general and noble metal nanoparticles in particular. We begin with an introduction to the advancements in this area followed by general aspects of the growth of anisotropic nanoparticles. Then we describe several important synthetic protocols for making anisotropic nanomaterials, followed by a summary of their assemblies, and conclude with major applications
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