Encrypting of Text Based on Chaotic Map

 مقدمة:        نظرًا للتوسع السريع للإنترنت مؤخرًا، أصبح الأمان مشكلة حاسمة عند نقل البيانات الرقمية عبر قنوات غير آمنة. يمكن تطبيق     ذلك من خلال استخدام طرق تشفير يمكن الاعتماد عليها. قدم هذا البحث نظامًا لتشفير النص لإنشاء قواعد بيانات آمنة. طرق العمل:          يستخدم البحث خريطة فوضوية مبنية على خريطة لوجستية نظرا لتطبيقها الواسع في البحث العلمي، حيث يتم استخدام عدة عمليات لتنفيذ نشاط التشفير. أولاً، تم تنسيق النص في مصفوفة ثنائية الأبعاد من الأرقام المحولة إلى متجه. ثانيًا، لإنشاء تسلسل لاستخدامه في عملية التشفير، يتم استخدام النظام الفوضوي. ثالثًا، فرز المتجه الذي تم إنشاؤه من أجل خلط القيم النصية بناءً عليه. تتضمن الخطوة الأخيرة ترميز النص المخفوق باستخدام عملية حسابية. أيضًا، هناك العديد من الخطوات المستخدمة في عملية فك التشفير. في الخطوة الأولى، يتم استخدام نفس الأسلوب الرياضي لفك تشفير النص المشفر بعد إنشاء التسلسل الفوضوي المتطابق. في الخطوة الثانية، يتم تفكيك القيم الممزوجة للحصول على النص الذي تم فك تشفيره. الاستنتاجات:          أظهرت النتائج التجريبية أن الطريقة المقترحة تحصل على قيمة ممتازة للإنتروبي تساوي (0.9955) ومعامل الارتباط يساوي      (-0.0024) وتأثير الانهيار الجليدي يساوي (0.5120) وكذلك النظام المقترح الذي تم فحصه تحت اختبارات NIST حصل على نتائج جيده (> 0.01) وتم فحصها لعدة ملفات أخرى والحصول على نتائج جيدة، من حيث اختبارات وقت التنفيذ، تم تطبيق النظام المقترح في فترة زمنية قصيرة.Background:                         Due to the internet's recent rapid expansion, security has become a crucial issue when transmitting digital data via unsecure channels. This can be applied by employing dependable encryption methods. This research brought forward a text encryption system order to create safe databases. Materials and Methods:         The research uses a chaotic map based on a logistic map Due to its widespread application in scientific research. Several processes are used to carry out the encryption activity. Firstly, the text is formatted in 2D matrix of numbers converted into vector. Secondly, to create a sequence for using it in the encryption process, the chaotic system is employed. Thirdly, sorting the generated vector in order to scramble the text values based on it. The final step involves encoding the scrambled text using a mathematical operation. Also, there are many steps used in the decryption process. In the first step, the same mathematical technique is used to decrypt the encrypted text after the identical chaotic sequence has been generated. In the second step, the scrambled values are descrambled to obtain the decrypted text. Results:        The experimental results demonstrate that the suggested approach obtain an excellent value of entropy equal to (0.9955) and Correlation coefficient equal to (-0.0024) and Avalanche effect equal to (0.5120) as well as the proposed system examined under NIST tests and obtain a good results (>0.01) and examined for multiple other files and obtain a good results, in terms of execution time tests, the proposed system applied in a short amount of time. Conclusion:      The proposed system matched the criteria for encryption techniques in terms of high sensitivity for initial values, high security, high randomizing Whatever text is to be encrypted. Also the proposed system can be applied for real time application due to its Short implementation time

Postoperative atrial fibrillation among patients undergoing isolated coronary artery bypass grafting

ntroduction Postoperative atrial fibrillation (AF) is the commonest of all the known cardiac arrhythmias after cardiac surgery. The postoperative AF has both short- and long-term adverse impacts on patients, like prolonged intensive care unit (ICU) stay, increased frequency of reoperations, myocardial infarction, increased use of inotropes, and intra-aortic balloon pump (IABP). There is a paucity of data regarding the postoperative AF after isolated coronary artery bypass grafting (CABG) and its risk factors in our geographic location. Therefore, the aim of this study was to determine the frequency of postoperative atrial fibrillation among patients undergoing isolated CABG at a tertiary care hospital of Karachi, Pakistan. Methods This prospective observational study was conducted on 163 consecutively selected patients undergoing first time isolated CABG at the Department of Cardiothoracic Surgery, Aga Khan University Hospital, Karachi. Patients with redo-sternotomy, preoperative atrial fibrillation and with other cardiac pathology were excluded from the study. Postoperative AF was defined in the patients with postoperative 12-lead electrocardiographic (ECG) finding of absence of P waves, replaced by unorganized electrical activity and irregular R-R intervals. Data analysis was carried out using IBM SPSS Statistics for Windows, Version 21.0 (IBM Corp., Armonk, NY, USA). Results A total of 163 patients were enrolled with the mean age of 58.66 ± 9.77 years ranging between 40 and 85 years with male predominance of 81% (132). The most common comorbidity was hypertension in about 68.1% (111), followed by diabetes mellitus in 54.6% (89) patients. Postoperative AF was observed in 42 (25.8%) patients. Most of the patients who developed postoperative AF, were overweight with mean body mass index (BMI) of 27.04 ± 4.85 kg/m2, 76.2% (32) had a history of hypertension, diabetes mellitus was associated with 33.3% (14) patients with postoperative AF and 50.0% (21) of them were smokers. Distribution of coronary artery disease in patients with postoperative AF was observed as three vessels coronary artery disease (3VCAD) in 83.3% (35), two-vessel coronary artery disease (2VCAD) was present in 7.1% (three), and rest of 9.5% (four) patients had single-vessel coronary artery disease (SVCAD). Conclusion The frequency of postoperative atrial fibrillation in our study was found to be 25.9% which is comparable to world literature. An important finding that comes through this study is a younger population undergoing CABG, which raises the possibility of early manifestation of ischemic heart disease in our region. This, however, needs further investigation. We were unable to point out the factors predictive of postoperative AF; studies with larger sample size would help in that regard

Effect of Dried Sewage Sludge on Compressive Strength of Concrete

Sewage sludge is a waste product generated from the wastewater treatment process at the treatment plant. The amount of sewage sludge produced is increases every year as the population increased. Poor management of sewage sludge will give negative impact to the environment. Replacing cement with sewage sludge ash is more significant to reduce the amount of waste material from sewage treatment plants. In this study, the various percentage of dried sewage sludge (DSS) has been added to replace the cement. Sewage sludge was dried in the oven with 100°C for 24 hours, then sieve through the sieve size 300 µm. Then, DSS was used in the concrete instead of cement with the replacement percentage of 0%, 5%, 10%, and 15% by weight. The compressive strength of concrete cube specimens was investigated after 7 and 28 days of curing. The results showed that the compressive strength of concrete specimens increased with the replacement of cement in concrete with 5 % to 10 % DSS, but the achieved maximum strength still lower compared to the control sample. However, the compressive strength of concrete specimens decreased when the DSS replacement of cement is more than 10 % by weight. The result of XRF test also showed that DSS has good potential to replace cement in concrete

An evaluation framework to determine the impact of the Lyme Bay Fisheries and Conservation Reserve and the activities of the Lyme Bay Consultative Committee on ecosystem services and human wellbeing.

This research evaluates the social and economic impact of the management measures that form the Lyme Bay Reserve and the partnership activities of the Lyme Bay Consultative Committee (LBCC) on Lyme Bay resource users. For the purpose of this evaluation it is the combination of the 2008 Statutory Instrument (SI) closure and the more recently designated Site of Community Interest (SCI) that form the boundary of the Lyme Bay Fisheries and Conservation Reserve, termed as the Lyme Bay Reserve. Data is analysed between 2005 and 2015. The results show that the habitats and species of Lyme Bay interact to support the delivery of several ecosystem processes (e.g. primary and secondary production, formation of species habitat) and the realisation of ecosystem services (e.g. fish for food). Overall it is clear that the closure of the area to mobile fishing gear has benefitted static gear fishermen by separating spatial conflict between gear types. The closure has enabled reef habitats to recover which in turn has supported increased catches of some reef associated species e.g. scallops. Further management and support measures agreed through the LBCC have clearly been successful in improving the well-being for those fishermen directly involved in the project. This research represents collaboration between Plymouth University, Exeter University, The Blue Marine Foundation and CEFAS. Input into the evaluation was provided by the Devon and Severn Inshore Fisheries and Conservation Authority (IFCA), the Southern IFCA, local fishermen and fishery representatives

Lay attitudes and misconceptions and their implications for the control of brucellosis in an agro-pastoral community in Kilombero district, Tanzania

Funding: The research for this paper was carried out within the framework of the DELTAS Africa Initiative [Afrique One-ASPIRE /DEL-15-008] (to CMM). Afrique One-ASPIRE is funded by a consortium of donor including the African Academy of Sciences (AAS) Alliance for Accelerating Excellence in Science in Africa (AESA), the New Partnership for Africa’s Development Planning and Coordinating (NEPAD) Agency, the Wellcome Trust [107753/A/15/Z] and the UK government. The authors were funded by Afrique One ASPIRE to conduct this study.Brucellosis is a priority zoonotic disease in Tanzania that causes ill-health in people and affects livestock productivity. Inadequate awareness and behavior risking transmission can impede control efforts. We conducted a cross-sectional survey of 333 livestock owners in three villages in the Kilombero district, Tanzania, to understand their awareness, knowledge and behavior associated with brucellosis. Six Focus Group Discussions (FGDs), two in each village, were conducted, as well as an additional FGD with male herders from one of the villages. Factors associated with knowledge on brucellosis, food consumption and animal husbandry behavior risking transmission of this disease, were identified using generalized linear models. Predictors for knowledge of brucellosis were being male and having a higher educational level, while age was positively associated with a higher level of knowledge. Faith and ethnicity were associated with the performance of practices risking transmission. Following traditional religion and belonging to the Wamaasai ethnicity significantly increased the odds of carrying out these practices. Qualitative analysis gave insight into risk practices and reasoning. Of the 333 respondents, 29% reported that they had experienced abortions in their herds, 14% witnessed retained placentas, and 8% had seen still-births in their cattle within the previous year. However, survey results also showed that only 7.2% of participants had heard about brucellosis as a disease in livestock. Of those who had heard about brucellosis in livestock, 91% associated abortions with it and 71% knew that humans can get infected through raw milk consumption. People overwhelmingly attributed symptoms and transmission of brucellosis in livestock to infection with trypanosomiasis and to supernatural reasons instead. In the community, consumption of raw milk was valued and handling of aborted material was not considered a risk for infection. This agro-pastoralist community holds on to long-held beliefs and practices and lacks understanding of the biomedical concept of brucellosis. Transmission routes and symptoms of brucellosis in humans and livestock are completely unknown. The disparity between risk perception and actual transmission risk related to animal handling and consumption of animal products presents a challenge for disease awareness communication. This study recommends focused community engagement and sensitization to address the limited awareness and misconceptions among agro-pastoralists.Publisher PDFPeer reviewe

Trends in left ventricular assist device use and outcomes among Medicare beneficiaries, 2004–2011

Objective: To characterise the trends in the left ventricular assist device (LVAD) implantation rates and outcomes between 2004 and 2011 in the Medicare population. Since the approval of the HeartMate II in 2008, the use of LVADs has steadily climbed. Given the increase in LVAD use, issues around discharge disposition, post-implant hospitalisations and costs require further understanding. Methods: We examined LVAD implantation rates and short-term and long-term outcomes among Medicare fee-for-service beneficiaries hospitalised for LVAD implantation. We also conducted analyses among survivors 1-year post-discharge to examine rehospitalisation rates. Lastly, we reported Centers for Medicare & Medicaid Services (CMS) payments for both index hospitalisation and rehospitalisations 1 year post-discharge. Results: A total of 2152 LVAD implantations were performed with numbers increasing from 107 in 2004 to 612 in 2011. The 30-day mortality rate decreased from 52% to 9%, and 1-year mortality rate decreased from 69% to 31%. We observed no change in overall length of stay, but post-procedure length of stay increased. We also found an increase in home discharge dispositions from 26% to 53%. Between 2004 and 2010, the rehospitalisation rate increased and the number of hospital days decreased. The adjusted CMS payment for the index hospitalisation increased from $188 789 to$225 697 over time but decreased for rehospitalisation from $60 647 to$53 630. Conclusions: LVAD implantations increased over time. We found decreasing 30-day and 1-year mortality rates and increasing home discharge disposition. The proportion of patients rehospitalised among 1-year survivors remained high with increasing index hospitalisation cost, but decreasing post-implantation costs over time

G-JITTER EFFECTS ON THE MIXED CONVECTION FLOW OF NANOFLUID PAST AN INCLINED STRETCHING SHEET

Mixed convection flows of nanofluid past an inclined stretching sheet with g-jitter effect is studied in this paper. Water based nanofluid containing copper, copper oxide, aluminium oxide and silver nanoparticles are concerned. Coupled nonlinear partial differential equations are solved using Kellerbox method. The effect of solid nanoparticles volume fraction parameter, frequency of oscillation and inclination angle parameter is observed to reduce the skin friction and heat transfer coefficients whereas mixed convection parameter increases both skin friction and heat transfer coefficients. Present study also shows that, the heat transfer coefficient is highest for silver nanofluid