43 research outputs found

    Optimization of approximate inhibitory rules relative to number of misclassifications

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    In this work, we consider so-called nonredundant inhibitory rules, containing an expression "attribute≠ value" on the right-hand side, for which the number of misclassifications is at most a threshold y. We study a dynamic programming approach for description of the considered set of rules. This approach allows also the optimization of nonredundant inhibitory rules relative to the length and coverage [1, 2]. The aim of this paper is to investigate an additional possibility of optimization relative to the number of misclassifications. The results of experiments with decision tables from the UCI Machine Learning Repository [3] show this additional optimization achieves a fewer misclassifications. Thus, the proposed optimization procedure is promising

    A pseudo feedback-based annotated TF-IDF technique for dynamic crypto-ransomware pre-encryption boundary delineation and features extraction

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    The cryptography employed against user files makes the effect of crypto-ransomware attacks irreversible even after detection and removal. Thus, detecting such attacks early, i.e. during pre-encryption phase before the encryption takes place is necessary. Existing crypto-ransomware early detection solutions use a fixed time-based thresholding approach to determine the pre-encryption phase boundaries. However, the fixed time thresholding approach implies that all samples start the encryption at the same time. Such assumption does not necessarily hold for all samples as the time for the main sabotage to start varies among different crypto-ransomware families due to the obfuscation techniques employed by the malware to change its attack strategies and evade detection, which generates different attack behaviors. Additionally, the lack of sufficient data at the early phases of the attack adversely affects the ability of feature extraction techniques in early detection models to perceive the characteristics of the attacks, which, consequently, decreases the detection accuracy. Therefore, this paper proposes a Dynamic Pre-encryption Boundary Delineation and Feature Extraction (DPBD-FE) scheme that determines the boundary of the pre-encryption phase, from which the features are extracted and selected more accurately. Unlike the fixed thresholding employed by the extant works, DPBD-FE tracks the pre-encryption phase for each instance individually based on the first occurrence of any cryptography-related APIs. Then, an annotated Term Frequency-Inverse Document Frequency (aTF-IDF) technique was utilized to extract the features from runtime data generated during the pre-encryption phase of crypto-ransomware attacks. The aTF-IDF overcomes the challenge of insufficient attack patterns during the early phases of the attack lifecycle. The experimental evaluation shows that DPBD-FE was able to determine the pre-encryption boundaries and extract the features related to this phase more accurately compared to related works

    Predictors of Medication Adherence and Blood Pressure Control among Saudi Hypertensive Patients Attending Primary Care Clinics: A Cross-Sectional Study

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    Purpose To assess the level of medication adherence and to investigate predictors of medication adherence and blood pressure control among hypertensive patients attending primary healthcare clinics in Makkah, Saudi Arabia. Patients and methods Hypertensive patients meeting the eligibility criteria were recruited from eight primary care clinics between January and May 2016 for this study. The patients completed Arabic version of Morisky Medication Adherence Scale (MMAS-8), an eight-item validated, self-reported measure to assess medication adherence. A structured data collection form was used to record patients’ sociodemographic, medical and medication data. Results Two hundred and four patients, of which 71.6% were females, participated in the study. Patients’ mean age was 59.1 (SD 12.2). The mean number of medication used by patients was 4.4 (SD 1.89). More than half (110; 54%) of the patients were non-adherent to their medications (MMAS score 65 years (OR 2.0 [95% CI: 1.0–4.2; P = 0.04]), and being diabetic (OR 0.25 [95% CI: 0.1–0.6; P = 0.04]) were found to be independent predictors of medication adherence. Conclusion Medication adherence is alarmingly low among hypertensive patients attending primary care clinics in Saudi Arabia which may partly explain observed poor blood pressure control. There is a clear need to educate patients about the importance of medication adherence and its impact on improving clinical outcomes. Future research should identify barriers to medication adherence among Saudi hypertensive patients

    Whole-genome sequencing of chronic lymphocytic leukemia identifies subgroups with distinct biological and clinical features

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    The value of genome-wide over targeted driver analyses for predicting clinical outcomes of cancer patients is debated. Here, we report the whole-genome sequencing of 485 chronic lymphocytic leukemia patients enrolled in clinical trials as part of the United Kingdom’s 100,000 Genomes Project. We identify an extended catalog of recurrent coding and noncoding genetic mutations that represents a source for future studies and provide the most complete high-resolution map of structural variants, copy number changes and global genome features including telomere length, mutational signatures and genomic complexity. We demonstrate the relationship of these features with clinical outcome and show that integration of 186 distinct recurrent genomic alterations defines five genomic subgroups that associate with response to therapy, refining conventional outcome prediction. While requiring independent validation, our findings highlight the potential of whole-genome sequencing to inform future risk stratification in chronic lymphocytic leukemia

    Measurements of electroweak W±Z boson pair production in association with two jets in pp collisions at √s = 13 TeV with the ATLAS detector

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    Measurements of integrated and differential cross-sections for electroweak W±Z production in association with two jets (W±Zjj) in proton-proton collisions are presented. The data collected by the ATLAS detector at the Large Hadron Collider from 2015 to 2018 at a centre-of-mass energy of √ s = 13 TeV are used, corresponding to an integrated luminosity of 140 fb−1 . The W±Zjj candidate events are reconstructed using leptonic decay modes of the gauge bosons. Events containing three identified leptons, either electrons or muons, and two jets are selected. Processes involving pure electroweak W±Zjj production at Born level are separated from W±Zjj production involving a strong coupling. The measured integrated fiducial cross-section of electroweak W±Zjj production per lepton flavour is σW Zjj−EW→ℓ ′ νℓℓjj = 0.368 ± 0.037 (stat.) ± 0.059 (syst.) ± 0.003 (lumi.) fb, where ℓ and ℓ ′ are either an electron or a muon. Respective cross-sections of electroweak and strong W±Zjj production are measured separately for events with exactly two jets or with more than two jets, and in three bins of the invariant mass of the two jets. The inclusive W±Zjj production cross-section, without separating electroweak and strong production, is also measured to be σW Zjj→ℓ ′ νℓℓjj = 1.462 ± 0.063 (stat.) ± 0.118 (syst.) ± 0.012 (lumi.) fb, per lepton flavour. The inclusive W±Zjj production cross-section is measured differentially for several kinematic observables. Finally, the measurements are used to constrain anomalous quartic gauge couplings by extracting 95% confidence level intervals on dimension-8 operators

    Measurement of vector boson production cross sections and their ratios using pp collisions at √s = 13.6 TeV with the ATLAS detector

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    Abstract available from publisher's website

    Beam-induced backgrounds measured in the ATLAS detector during local gas injection into the LHC beam vacuum

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    Inelastic beam-gas collisions at the Large Hadron Collider (LHC), within a few hundred metres of the ATLAS experiment, are known to give the dominant contribution to beam backgrounds. These are monitored by ATLAS with a dedicated Beam Conditions Monitor (BCM) and with the rate of fake jets in the calorimeters. These two methods are complementary since the BCM probes backgrounds just around the beam pipe while fake jets are observed at radii of up to several metres. In order to quantify the correlation between the residual gas density in the LHC beam vacuum and the experimental backgrounds recorded by ATLAS, several dedicated tests were performed during LHC Run 2. Local pressure bumps, with a gas density several orders of magnitude higher than during normal operation, were introduced at different locations. The changes of beam-related backgrounds, seen in ATLAS, are correlated with the local pressure variation. In addition the rates of beam-gas events are estimated from the pressure measurements and pressure bump profiles obtained from calculations. Using these rates, the efficiency of the ATLAS beam background monitors to detect beam-gas events is derived as a function of distance from the interaction point. These efficiencies and characteristic distributions of fake jets from the beam backgrounds are found to be in good agreement with results of beam-gas simulations performed with theFluka Monte Carlo programme

    Protective Effect of Vitamin D against Hepatic Molecular Apoptosis Caused by a High-Fat Diet in Rats

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    The protective effects of vitamin D (VitD) in different diseases were studied. The liver is of great interest, especially with the presence of VitD receptors. A high-fat diet (HFD) is associated with many diseases, including liver injury. Consumption of saturated fatty acids triggers hepatic apoptosis and is associated with increased inflammation. We aimed in this study to investigate the protective effects of VitD on hepatic molecular apoptotic changes in response to an HFD in rats. Forty male Wistar albino rats were used and divided into four groups: control, HFD, control + VitD, and VitD-supplemented HFD (HFD + VitD) groups. After six months, the rats were sacrificed, and the livers were removed. RNA was extracted from liver tissues and used for the quantitative real-time RT-PCR of different genes: B-cell lymphoma/leukemia-2 (BCL2), BCL-2-associated X protein (Bax), Fas cell surface death receptor (FAS), FAS ligand (FASL), and tumor necrosis factor α (TNF-α). The results showed that an HFD increased the expression of the pro-apoptotic genes Bax, FAS, and FASL, and reduced the expression of the anti-apoptotic gene BCL2. Interestingly, a VitD-supplemented HFD significantly increased the BCL2 expression and decreased the expression of all pro-apoptotic genes and TNFα. In conclusion, VitD has a protective role against hepatic molecular apoptotic changes in response to an HFD

    A Novel Antifouling RO Polyamide/Myrrh Membrane for Waste Water Purification

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    In the present work, desalination of real samples from Dumat Al-Jandal Lake water (located in Jouf region) was carried out via reverse osmosis (RO) technique. The growth of bacteria on the surface of RO membrane is an essential issue of this method. It creates defects in membrane properties as salt rejection and preparation. Many approaches have been proposed to prevent the growth of bacteria on membrane. The addition of some materials such as natural products was one of those approaches. In this work, myrrh was chosen because it is well known as an antibacterial natural product. Unmodified RO membrane was prepared in the lab using interfacial polymerization between trimesoyl chloride (TMC, 0.1 M) and m-phenylenediamine (MPD, 0.3 M). The characterization was obtained by using infrared (IR) and scanning electron microscopy (SEM). The properties of RO membrane as water flux and salt rejection were determined using lake water. The obtained results were 25 and 65% for water flux and salt rejection, respectively. In respect of modified RO membrane, myrrh solution with different concentrations was prepared and mixed with membrane materials. The modified membrane was characterized with IR and SEM. Water flux and salt rejection were determined obtaining results of 42 and 41% for water flux and salt rejection, respectively. The resistance of bacterial growth was tested for both modified and unmodified membranes, showing that the modified membrane presented high resistance of bacterial growth in contrast to the unmodified one

    The Rapidly Changing Patterns in Bacterial Co-Infections Reveal Peaks in Limited Gram Negatives during COVID-19 and Their Sharp Drop Post-Vaccination, Implying Potential Evolution of Co-Protection during Vaccine–Virus–Bacterial Interplay

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    SARS-CoV-2 has caused the most devastating pandemic of all time in recent human history. However, there is a serious paucity of high-quality data on aggravating factors and mechanisms of co-infection. This study aimed to identify the trending patterns of bacterial co-infections and types and associated outcomes in three phases of the pandemic. Using quality hospital data, we have investigated the SARS-CoV-2 fatality rates, profiles, and types of bacterial co-infections before, during, and after COVID-19 vaccination. Out of 389 isolates used in different aspects, 298 were examined before and during the pandemic (n = 149 before, n = 149 during). In this group, death rates were 32% during compared to only 7.4% before the pandemic with significant association (p-value = 0.000000075). However, the death rate was 34% in co-infected (n = 170) compared to non-co-infected patients (n = 128), indicating a highly significant value (p-value = 0.00000000000088). However, analysis of patients without other serious respiratory problems (n = 28) indicated that among the remaining 270 patients, death occurred in 30% of co-infected patients (n = 150) and only 0.8% of non-co-infected (n = 120) with a high significant p-value = 0.00000000076. The trending patterns of co-infections before, during, and after vaccination showed a significant decline in Staphylococcus aureus with concomitant peaks in Gram negatives n = 149 before/n = 149 during, including Klebsiella pneumonian = 11/49 before/during, E. coli n = 10/24, A. baumannii n = 8/25, Ps. aeruginosa n = 5/16, and S. aureus 13/1. Nevertheless, in the post-vaccination phase (n = 91), gender-specific co-infections were examined for potential differences in susceptibility. Methicillin-resistant S. aureus dominated both genders followed by E. coli in males and females, with the latter gender showing higher rates of isolations in both species. Klebsiella pneumoniae declined to third place in male patients. The drastic decline in K. pneumoniae and Gram negatives post-vaccination strongly implied a potential co-protection in vaccines. Future analysis would gain more insights into molecular mimicry
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