73 research outputs found

    Reliable cost-optimal deployment of wireless sensor networks

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    Wireless Sensor Networks (WSNs) technology is currently considered one of the key technologies for realizing the Internet of Things (IoT). Many of the important WSNs applications are critical in nature such that the failure of the WSN to carry out its required tasks can have serious detrimental effects. Consequently, guaranteeing that the WSN functions satisfactorily during its intended mission time, i.e. the WSN is reliable, is one of the fundamental requirements of the network deployment strategy. Achieving this requirement at a minimum deployment cost is particularly important for critical applications in which deployed SNs are equipped with expensive hardware. However, WSN reliability, defined in the traditional sense, especially in conjunction with minimizing the deployment cost, has not been considered as a deployment requirement in existing WSN deployment algorithms to the best of our knowledge. Addressing this major limitation is the central focus of this dissertation. We define the reliable cost-optimal WSN deployment as the one that has minimum deployment cost with a reliability level that meets or exceeds a minimum level specified by the targeted application. We coin the problem of finding such deployments, for a given set of application-specific parameters, the Minimum-Cost Reliability-Constrained Sensor Node Deployment Problem (MCRC-SDP). To accomplish the aim of the dissertation, we propose a novel WSN reliability metric which adopts a more accurate SN model than the model used in the existing metrics. The proposed reliability metric is used to formulate the MCRC-SDP as a constrained combinatorial optimization problem which we prove to be NP-Complete. Two heuristic WSN deployment optimization algorithms are then developed to find high quality solutions for the MCRC-SDP. Finally, we investigate the practical realization of the techniques that we developed as solutions of the MCRC-SDP. For this purpose, we discuss why existing WSN Topology Control Protocols (TCPs) are not suitable for managing such reliable cost-optimal deployments. Accordingly, we propose a practical TCP that is suitable for managing the sleep/active cycles of the redundant SNs in such deployments. Experimental results suggest that the proposed TCP\u27s overhead and network Time To Repair (TTR) are relatively low which demonstrates the applicability of our proposed deployment solution in practice

    In AUC, a stigma lives on

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    In the American University in Cairo, Egypt\u27s most mentally liberated campus, many students are still reluctant when it comes to addressing the Student Counseling Center when they are facing problems. AUC\u27s Dina Salah ElDin reports

    Bridging the gap between research and agile practice: an evolutionary model

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    There is wide acceptance in the software engineering field that industry and research can gain significantly from each other and there have been several initiatives to encourage collaboration between the two. However there are some often-quoted challenges in this kind of collaboration. For example, that the timescales of research and practice are incompatible, that research is not seen as relevant for practice, and that research demands a different kind of rigour than practice supports. These are complex challenges that are not always easy to overcome. Since the beginning of 2013 we have been using an approach designed to address some of these challenges and to bridge the gap between research and practice, specifically in the agile software development arena. So far we have collaborated successfully with three partners and have investigated three practitioner-driven challenges with agile. The model of collaboration that we adopted has evolved with the lessons learned in the first two collaborations and been modified for the third. In this paper we introduce the collaboration model, discuss how it addresses the collaboration challenges between research and practice and how it has evolved, and describe the lessons learned from our experience

    Color Image Encryption Using LFSR, DNA, and 3D Chaotic Maps

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    One of the most important challenges facing researchers is to find new methods to protect data sent over the Internet and prevent unauthorized access to it. In this paper, we present a new method for encrypting image data divided into two stages. The first stage requires redistributing the positions of the pixels by using a key of random numbers generated by linear feedback shift registers and then encrypting the data using deoxyribonucleic acid rules. The data generated in the previous stage is encrypted again using chaotic maps to increase the level of security in the second stage. Several statistical tests were implemented to verify the efficiency of the proposed method and compare the results with the work of other researchers. The results of the tests proved a reasonable safety rate compared to other techniques

    Value of serum tenascin-C in patients with acute myocardial infarction

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    Background: Myocardial infarction (MI) is defined as myocardial cell necrosis due to significant and sustained ischemia. TN-C is an extracellular matrix glycoprotein  that is expressed in several important steps during the very early stage of cardiogenesis. TN-C is not normally expressed in the adult heart, but transiently appears during pathological conditions and plays important roles in tissue remodeling.Aim: To study the role of TN-C in myocardial infarction patients and to evaluate its role as a predictor of HF in these patients.Methods: This study was conducted on 45 cases uniformly divided into 3 closely  matched (in age and sex) groups as follows: Group (I) includes 15 patients who were suffering from AMI; Group (II) includes 15 patients who were suffering from HF on top of MI; and Group (III) includes 15 healthy volunteers coming for regular annual checkup. 3–6 ml venous blood was collected on the day of admission under complete aseptic conditions and stored at 70 C until assayed by ELISA.Results: TN-C levels in the sera of patients with AMI Group (I) were significantly higher than those of healthy volunteers. Moreover, in Group I ofAMI, a positive  correlation between TN-C level on one side and CK, CK-MB and troponin T level on the other side was found. TN-C levels in the sera of patients with congestive heart failure on top of acute MI Group (II) were significantly higher than those of healthy volunteers. Pro-BNP levels in patients with heart failure Group (II) were significantlyhigher than those with AMI not complicated with heart failure Group (I). Levels of pro-BNP were also positively correlated with those of TN-C in patients with heart failure on top of AMI Group (II).Conclusions: Serum TN-C might be a novel marker reflecting active structural  remodeling in the myocardium following infarction, with high TN-C levels at acute stages possibly predicting progression of LV remodeling. Also, the incorporation of a combination of serum TN-C and plasma BNP levels may improve risk stratification for congestive heart failure after AMI. Further studies on large scale are needed for more evaluation of TN-C role in HF

    Agile challenges in practice: a thematic analysis

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    As agile is maturing and becoming more widely adopted, it is important that researchers are aware of the real-world challenges faced by practitioners and organisations. We undertook a thematic analysis of 193 agile challenges collected at a series of agile conferences and events during 2013 and 2014. Participants were mainly practitioners and business representatives along with some academics. The challenges were thematically analysed by separate authors, synthesised, and a list of seven themes and twenty-seven sub-themes was agreed. Themes were Organisation, Sustainability, Culture, Teams, Scale, Value and Misconceptions and shortcomings. We compare our findings against previous attempts to identify and categorise agile challenges. While most themes have persisted we found a shift of focus towards issues related to sustainability, business engagement and transformation, as well as misconceptions and shortcomings. We identify areas for further research and a need for more innovative methods of conveying academic research to industry and industrial problems to academi

    Determinants of Exclusive Breastfeeding in a Sample of Egyptian Infants

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    BACKGROUND: Breastfeeding is an optimum, healthy, and economical mode of feeding an infant. However, many preventable obstacles hinder exclusive breastfeeding in the first six months of life. AIM: We aimed to assess the social-, maternal- and infant-related factors disturbing exclusive breastfeeding in the first six months of life. METHODS: It is a retrospective study included 827 dyads of mothers and infants older than 6 months (411 exclusively breastfed, 311 artificially-fed and 105 mixed feds). Mothers were interviewed to obtain sociodemographic information, maternal medical history and perinatal history and a detailed history of infant feeding. RSULTS: Many factors were found to support the decision for artificial feeding rather than exclusive breastfeeding, including maternal age < 25 years (OR = 2.252), child birth order > 3rd (OR = 2.436), being a primi-para (OR = 1.878), single marital status (OR = 2.762), preterm infant (OR = 3.287) and complicated labor (OR = 1.841). Factors in favor of mixed feeding included cesarean section (OR = 2.004) and admission to the Neonatal Intensive Care Unit (OR = 1.925). CONCLUSIONS: Although it isn’t a community-based study and its results can’t be generalised, plans to improve health and development of children are preferable to include the following: health education and awareness programs about the importance of exclusive breastfeeding should be directed for young and first-time mothers. Improved antenatal care to reduce perinatal and neonatal problems; and training, monitoring, and supervising community health care workers to recognise labour complications and provide support and knowledge to lactating mothers

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Medical prospects of cryptosporidiosis in vivo control using biofabricated nanoparticles loaded with Cinnamomum camphora extracts by Ulva fasciata

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    Background and Aim: Global efforts are continuing to develop preparations against cryptosporidiosis. This study aimed to investigate the efficacy of biosynthesized Ulva fasciata loading Cinnamomum camphora oil extract on new zinc oxide nanoparticles (ZnONPs shorten to ZnNPs) and silver nanoparticles (AgNPs) as alternative treatments for Cryptosporidium parvum experimental infection in rats. Materials and Methods: Oil extract was characterized by gas chromatography-mass spectrometry, loaded by U. fasciata on ionic-based ZnO and NPs, and then characterized by transmission electron microscopy, scanning electron microscopy, and X-ray diffraction. Biosafety and toxicity were investigated by skin tests. A total of 105 C. parvum oocysts/rat were used (n = 81, 2–3 W, 80–120 g, 9 male rats/group). Oocysts shedding was counted for 21 d. Doses of each preparation in addition to reference drug were administered daily for 7 d, starting on post-infection (PI) day (3). Nitazoxanide (100 mg) was used as the reference drug. After 3 weeks, the rats were sacrificed for postmortem examination and histopathological examination. Two blood samples/rat/group were collected on the 21st day. Ethylenediaminetetraacetic acid blood samples were also used for analysis of biochemistry, hematology, immunology, micronucleus prevalence, and chromosomal abnormalities. Results: C. camphora leaves yielded 28.5 ± 0.3 g/kg oil and 20 phycocompounds were identified. Spherical and rod-shaped particles were detected at 10.47–30.98 nm and 18.83–38.39 nm, respectively. ZnNPs showed the earliest anti-cryptosporidiosis effect during 7–17 d PI. Other hematological, biochemical, immunological, histological, and genotoxicity parameters were significantly fruitful; hence, normalized pathological changes induced by infestation were observed in the NPs treatments groups against the infestation-free and Nitazoxanide treated group. Conclusion: C. camphora, U. fasciata, ZnNPs, and AgNPs have refluxed the pathological effects of infection as well as positively improved host physiological condition by its anticryptosporidial immunostimulant regenerative effects with sufficient ecofriendly properties to be proposed as an alternative to traditional drugs, especially in individuals with medical reactions against chemical commercial drugs

    Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

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    Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication
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