4,489 research outputs found
Central flow control software development: A case study of the effectiveness of software engineering techniques
Edukasi Anti Penyalahgunaan Obat Kepada Siswa SD di Kota Palu melalui Media Kartu Kuartet: Education Of Anti-drug Abuse For Elementary School Students In Palu Citythrough Quartet Card Media
Cases of illegal drugs and drug abuse in the elementary school community in Indonesia is increasingly massive and alarming. An innovation to protect elementary school students from that situation is through the colaboration of academics from Bandung Institute of Technology with FDA in Palu in the form education of anti-drug abuse for elementary school students through quartet card media. The aim of the study was to determine the effect of the education on anti-drug abuse knowledge in fifth grade students in Palu City. The research method used pre-experimental design with the design of one group pretest-posttest on three elementary schools which were representatives of three ranks namely; good, quite good and not good based on the results of the Smart-Accurate Quiz FDA in Palu for elementary school level in 2017. The sampling technique used purposive sampling. Observation of knowledge of elementary students using questionnaires that have been tested for validity and reliability had been carried out. The pretest and posttest were conducted before and after education. The comparison of pretest and posttest data in each elementary school was analyzed using paired T test whereas for all elementary school data analyzed using the Wilcoxon test with hypotheses. There was an influence of anti-drug abuse education through quartet card media on anti-drug abuse knowledge in fifth grade students in Palu City. The results showed that there was an influence of education on anti-drug abuse knowledge in fifth grade students from elementary school representatives “good and quite good ranking” with p values of 0.005 and p ≤ 0.001, while in elementary schools representatives “not good ranking”, the education did not influence their knowledge with a p value of 0.149. Analysis of the Wilcoxon test in all elementary schools showed a p value p ≤ 0,001, which meant that education had an influence on the knowledge of fifth grade students in elementary schools in Palu City
Revisiting the Core Ontology and Problem in Requirements Engineering
In their seminal paper in the ACM Transactions on Software Engineering and
Methodology, Zave and Jackson established a core ontology for Requirements
Engineering (RE) and used it to formulate the "requirements problem", thereby
defining what it means to successfully complete RE. Given that stakeholders of
the system-to-be communicate the information needed to perform RE, we show that
Zave and Jackson's ontology is incomplete. It does not cover all types of basic
concerns that the stakeholders communicate. These include beliefs, desires,
intentions, and attitudes. In response, we propose a core ontology that covers
these concerns and is grounded in sound conceptual foundations resting on a
foundational ontology. The new core ontology for RE leads to a new formulation
of the requirements problem that extends Zave and Jackson's formulation. We
thereby establish new standards for what minimum information should be
represented in RE languages and new criteria for determining whether RE has
been successfully completed.Comment: Appears in the proceedings of the 16th IEEE International
Requirements Engineering Conference, 2008 (RE'08). Best paper awar
Snoop behaviour in multihop wireless networks
"© ACM, 2011. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version was published in Proceedings of the Fifth ACM International Workshop on Performance Monitoring, measurement and Evaluation of heterogeneous wireless and wired networks 2011 http://doi.acm.org/10.1145/1868612.1868623"Snoop is one proposal for improving TCP throughput in wireless networks. We investigated the application of this protocol in wireless ad hoc networks and observed that a single hop in the ad hoc network experienced large variations in round trip time in a very short period. Without changes to the Snoop protocol to accommodate these dramatic RTT variations, Snoop was performing badly compared with regular TCP even when there were no packet losses or errors. The main cause for poor performance premature retransmissions performed by Snoop. We have modified the Snoop protocol to avoid these unnecessary retransmissions by having a higher local retransmission timeout. The results show us that Snoop benefits from this approach which has made a significant performance improvement over regular TCP in multihop wireless network
An Overview of Current Clinical Trials of Agents for the Treatment and Prevention of COVID-19 in the United States
Introduction: Given the rapid worldwide spread of SARS-CoV-2 and the attendant risks for severe complications and mortality, numerous clinical trials for its treatment and prevention have been generated in a short period. This report focuses on the categories of the wide spectrum of agents being studied in the United States and the intensity of effort involved with each so that clinicians may consider whether suggesting enrollment may be appropriate for their patients.
Methods: A search was completed of the ClinicalTrials.gov database on May 28, 2020 for all such trials underway as of that date in the US. A total 190 trials were identified; of these, 151 trials that included 83 distinct agents met the specified delimiting criteria. The salient features of each, including medication class, the total number of trials involving either treatment or ongoing prevention strategies, and the total patient enrollment, were captured in a summary table. Comprehensive descriptors of all 190 trials are made available in an appendix.
Results: The antimalarial agent hydroxychloroquine was the most frequently studied single agent by both number of trials and number of subjects involved. Antivirals were the next largest group, followed by immunomodulators, antibacterials, vaccines, renin-angiotensin-aldosterone system (RAAS) antagonists, and convalescent plasma. Of note, repurposed antineoplastic agents, stem cell therapies, steroids, and a diverse range of miscellaneous agents were also included in the list.
Conclusions: The agents currently under study for the prevention or treatment of COVID-19 include several highly publicized pharmaceuticals as well as a wide array of other experimental medications and novel applications of established drugs. In the absence of an approved vaccine at this time, it is essential that clinicians be aware of the range of trials from which important new therapeutic and prophylactic advances may rapidly emerge
The structure of human CD23 and its interactions with IgE and CD21
The low-affinity immunoglobulin E (IgE) receptor, CD23 (FcɛRII), binds both IgE and CD21 and, through these interactions, regulates the synthesis of IgE, the antibody isotype that mediates the allergic response. We have determined the three-dimensional structure of the C-type lectin domain of CD23 in solution by nuclear magnetic resonance spectroscopy. An analysis of concentration-dependent chemical shift perturbations have allowed us to identify the residues engaged in self-association to the trimeric state, whereas ligand-induced changes have defined the binding sites for IgE and CD21. The results further reveal that CD23 can bind both ligands simultaneously. Despite the C-type lectin domain structure, none of the interactions require calcium. We also find that IgE and CD23 can interact to form high molecular mass multimeric complexes. The interactions that we have described provide a solution to the paradox that CD23 is involved in both up- and down-regulation of IgE and provide a structural basis for the development of inhibitors of allergic disease
Convergence Conditions for Random Quantum Circuits
Efficient methods for generating pseudo-randomly distributed unitary
operators are needed for the practical application of Haar distributed random
operators in quantum communication and noise estimation protocols. We develop a
theoretical framework for analyzing pseudo-random ensembles generated through a
random circuit composition. We prove that the measure over random circuits
converges exponentially (with increasing circuit length) to the uniform (Haar)
measure on the unitary group and describe how the rate of convergence may be
calculated for specific applications.Comment: 4 pages (revtex), comments welcome. v2: reference added, title
changed; v3: published version, minor changes, references update
Polynomial Cointegration among Stationary Processes with Long Memory
n this paper we consider polynomial cointegrating relationships among
stationary processes with long range dependence. We express the regression
functions in terms of Hermite polynomials and we consider a form of spectral
regression around frequency zero. For these estimates, we establish consistency
by means of a more general result on continuously averaged estimates of the
spectral density matrix at frequency zeroComment: 25 pages, 7 figures. Submitted in August 200
An efficient algorithm for learning with semi-bandit feedback
We consider the problem of online combinatorial optimization under
semi-bandit feedback. The goal of the learner is to sequentially select its
actions from a combinatorial decision set so as to minimize its cumulative
loss. We propose a learning algorithm for this problem based on combining the
Follow-the-Perturbed-Leader (FPL) prediction method with a novel loss
estimation procedure called Geometric Resampling (GR). Contrary to previous
solutions, the resulting algorithm can be efficiently implemented for any
decision set where efficient offline combinatorial optimization is possible at
all. Assuming that the elements of the decision set can be described with
d-dimensional binary vectors with at most m non-zero entries, we show that the
expected regret of our algorithm after T rounds is O(m sqrt(dT log d)). As a
side result, we also improve the best known regret bounds for FPL in the full
information setting to O(m^(3/2) sqrt(T log d)), gaining a factor of sqrt(d/m)
over previous bounds for this algorithm.Comment: submitted to ALT 201
Identification of Multiple Pancreatic and Extra-Pancreatic Pathways Underlying the Glucose-Lowering Actions of Acacia arabica Bark in Type-2 Diabetes and Isolation of Active Phytoconstituents
Acacia arabica is used traditionally to treat a variety of ailments, including diabetes. This study elucidated the antidiabetic actions of A. arabica bark together with the isolation of bioactive molecules. Insulin secretion and signal transduction were measured using clonal β cells and mouse islets. Glucose uptake was assessed using 3T3-L1 adipocytes, and in vitro systems assessed additional glucose-lowering actions. High-fat-fed (HFF) obese rats were used for in vivo evaluation, and phytoconstituents were isolated and characterised by RP-HPLC followed by LC-MS and NMR. Hot-water extract of A. arabica (HWAA) increased insulin release from clonal β cells and mouse islets by 1.3–6.8-fold and 1.6–3.2-fold, respectively. Diazoxide, verapamil and calcium-free conditions decreased insulin-secretory activity by 30–42%. In contrast, isobutylmethylxanthine (IBMX), tolbutamide and 30 mM KCl potentiated the insulin-secretory effects. The mechanism of actions of HWAA involved membrane depolarisation and elevation of intracellular Ca2+ together with an increase in glucose uptake by 3T3-L1 adipocytes, inhibition of starch digestion, glucose diffusion, dipeptidyl peptidase-IV (DPP-IV) enzyme activity and protein glycation. Acute HWAA administration (250 mg/5 mL/kg) enhanced glucose tolerance and plasma insulin in HFF obese rats. Administration of HWAA (250 mg/5 mL/kg) for 9 days improved glucose homeostasis and β-cell functions, thereby improving glycaemic control, and circulating insulin. Isolated phytoconstituents, including quercetin and kaempferol, increased insulin secretion in vitro and improved glucose tolerance. The results indicate that HWAA has the potential to treat type 2 diabetes as a dietary supplement or as a source of antidiabetic agents, including quercetin and kaempferol
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