Improving spam email classification accuracy using ensemble techniques: a stacking approach

Spam emails pose a substantial cybersecurity danger, necessitating accurate classification to reduce unwanted messages and mitigate risks. This study focuses on enhancing spam email classification accuracy using stacking ensemble machine learning techniques.We trained and tested five classifiers: logistic regression, decision tree, K-nearest neighbors (KNN), Gaussian naive Bayes and AdaBoost. To address overfitting, two distinct datasets of spam emails were aggregated and balanced. Evaluating individual classifiers based on recall, precision and F1 score metrics revealed AdaBoost as the top performer. Considering evolving spam technology and new message types challenging traditional approaches, we propose a stacking method. By combining predictions from multiple base models, the stacking method aims to improve classification accuracy. The results demonstrate superior performance of the stacking method with the highest accuracy (98.8%), recall (98.8%) and F1 score (98.9%) among tested methods. Additional experiments validated our approach by varying dataset sizes and testing different classifier combinations. Our study presents an innovative combination of classifiers that significantly improves accuracy, contributing to the growing body of research on stacking techniques. Moreover, we compare classifier performances using a unique combination of two datasets, highlighting the potential of ensemble techniques, specifically stacking, in enhancing spam email classification accuracy. The implications extend beyond spam classification systems, offering insights applicable to other classification tasks. Continued research on emerging spam techniques is vital to ensure long-term effectiveness

Reliability and validity of WATCH: Warwick assessment instrument for clinical teaching

Objective: To determine the reliability, validity, feasibility, acceptability and perceived educational impact of WATCH: Warwick Assessment insTrument for Clinical teacHing among doctors in Pakistan.Study design: Cross-sectional research study.Place and duration of study: The College of Physicians and Surgeons, Pakistan, from September 2018 to August 2019.Methodology: Postgraduate trainees were asked to rate the clinical teaching sessions, using WATCH, which consists of 15 items. Percentage was used to calculate gender and participation from different specialties. Inter-item correlations of 15 items with individual mean scores, standard deviations and Cronbach\u27s Alpha were reported, including Friedman test, in order to observe the scores across multiple conditions. The Hotelling\u27s T2 test was used to test whether the answers provided by the study participants to the questionnaire were equal. Construct validity was determined using factor analysis while feasibility, acceptability, and educational impact was evaluated by seeking participants\u27 feedback on five semi-structured questions.Results: More than 80% ranked WATCH from good to excellent. Oveall 8 items were perceived as excellent, while 7 items received rating of good. Inter-item correlation ranged from 0.61 to 0.81. Cronbach Alpha was reported to be 0.975, with significant difference in mean scores of different items (Friedman\u27s Chi-Square=4285.54; p\u3c0.001). The Hotelling\u27s T2 test (21598.871 with F=185.249, df=14,2654; p\u3c0.001) indicated that the mean values of the responses of different questions in the instrument were statiscally different. Factor analysis indicated one factor accounting for 73.97 of variance. The majority (93%) of the participants found the instrument easy to complete, most participants (91.5%) indicated it as an acceptable method of assessment, and majority (90.8%) perceived that it can improve clinical teaching.Conclusion: WATCH demonstrated valid, reliable, feasible, and acceptable results for assessment of teaching of medical doctors and it can be used for providing feedback and rewarding teachers who excel in teaching. Key Words: Clinical teaching, Validity, Reliability, Feasibility, Medical students, Residents, Doctors

Development and release kinetics of a novel formulation of nimesulide prepared by microencapsulation using synthetic polymers

The synthetic polymers and their combinations were employed to retard the release of nimesulide from microcapsules. Microcapsules were prepared in different ratios of Eudragit RL 100 and hydroxy propyl methyl cellulose (HPMC) separately and in combination. All formulations of microcapsules were compressed to tablets. Dissolution of microcapsules and their tablets was performed by USP-apparatus-II in 900 mL borate buffer of pH 8.4 at 37.0 ± 0.5 ºC, at 50 rpm. In vitro kinetics was determined by various models including Zero order, First Order, Higuchi, Korsmeyer-Peppas and Hixson-Crowell. Eudragit showed higher retarding effect over extended period of time on release of drug than HPMC alone or its combination with Eudragit.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Impact of 10-valent pneumococcal conjugate vaccine (PCV10) on nasopharyngeal carriage in children 2 years of age: Data from a four-year time series cross-sectional study from Pakistan

The dataset described in this paper was collected for a time-series cross-sectional study exploring the impact of 10-valent Pneumococcal Conjugate Vaccine (PCV10) on nasopharyngeal (NP) carriage in children under 2 years of age from a rural population in Sindh, Pakistan. The study was carried out in two union councils of Matiari - Khyber and Shah Alam Shah Jee Wasi (Latitude 25.680298 / Longitude 68.502711). Data was collected on socio-demographics, clinical characteristics and vaccination status using android phone-based application. NP samples were collected using standard World Health Organisation (WHO) techniques, culture and serotyping was done using sequential Multiplex PCR described by Centre for Disease Control, USA. We looked at the carriage rate of vaccine type (VT) and non-vaccine type (NVT) serotypes over time in vaccinated and unvaccinated children. We additionally looked at the predictors for pneumococcal carriage. The uploaded dataset, available on Mendeley data repository (Nisar, Muhammad Imran (2021), Impact of PCV10 on nasopharyngeal carriage in children in Pakistan , Mendeley Data, V1, doi:10.17632/t79h6g97gr.1), has 3140 observations in CSV format. Additional files uploaded include a data dictionary and the set of questionnaires. The dataset and accompanying files can be used by other interested researchers to replicate our analysis, carry similar analysis under varying set of assumptions or perform additional exploratory or metanalysis

Direct and indirect effect of 10 valent pneumococcal vaccine on nasopharyngeal carriage in children under 2 years of age in Matiari, Pakistan

Background: Pakistan introduced Ten-valent pneumococcal-conjugate-vaccine PCV10 in 2012 as a 3 + 0 schedule without catch-up.Methods: Children \u3c2 years old in Matiari, Sindh provided nasopharyngeal swabs between 2014 and 2018, which were cultured for pneumococcus and serotyped through multiplex PCR at the Aga Khan University Hospital. Carriage rates over time for Vaccine-Type (VT) and Non-VT (NVT) serotypes were used to estimate direct, indirect, total and overall effects of vaccination. Regression analysis was used to determine factors associated with VT carriage.Results: Pneumococcus was detected in 2370/3140 (75%). VT carriage decreased overall, 16.1-9.6% (p-trend \u3c0.001); vaccinated (all 3 doses of PCV10 received) 11.3-8.1% (p-trend 0.031) and unvaccinated (no PCV10 dose received) 17.4-10.3% (p-trend 0.003) with a decline in serotypes 6B, 9V/9A and 19F. Immunization increased from 41.0% to 68.4% (p-trend 0.001). Direct effect of vaccine was 32.8% (95% CI 14.7-47.0%) and indirect effect 44.6%(95% CI 40.6-48.6%). Factors associated with decreased VT colonization were education 1-5 years (aOR 0.7, 95%CI 0.6-1.0), history of difficulty breathing (aOR 0.7, 95%CI 0.5-1.0), exposure to smoke (aOR 0.8, 95% CI 0.6-1.0), child fully immunized (aOR 0.7, 95%CI 0.5-1.0) and enrolled in 3rd (aOR 0.6, 95%CI 0.4-0.8) and 4th (aOR 0.6, 95%CI 0.5-0.9) year of the study whereas history of runny nose (aOR 1.5, 95% CI 1.2-1.9) was positively associated.Conclusions: Decrease in VT pneumococcal carriage in vaccinated and unvaccinated children indicates herd immunity. Sustained increase in vaccine coverage and close long-term surveillance is warranted

Air Pollution and Clean Energy: Latest Trends and Future Perspectives

Energy and the environment are among the top global issues of this era. Environmental degradation specifically due to consumption of fossil fuels in conventional energy generation systems has become a critical challenge for the whole world. With the introduction of advance industrial processes and operations, the air quality deterioration has also become very complex. There is a dire need to replace the conventional energy systems with alternative energy resources for reducing air pollutants. Renewable energy systems generate clean energy with less environmental footprints. This chapter will highlight the latest trends and future strategies in clean and renewable energy supply systems to mitigate air pollution for environmental sustainability

Antibiotic consumption at community pharmacies : a multicenter repeated prevalence surveillance using WHO methodology

Background: Antibiotics are losing their effectiveness because of the rapid emergence of resistant bacteria. Unnecessary antimicrobial use increases antimicrobial resistance (AMR). There are currently no published data on antibiotic consumption in Pakistan at the community level. This is a concern given high levels of self-purchasing of antibiotics in Pakistan and variable knowledge regarding antibiotics and AMR among physicians and pharmacists. Objective: The objective of this repeated prevalence survey was to assess the pattern of antibiotic consumption data among different community pharmacies to provide a baseline for developing future pertinent initiatives. Methods: A multicenter repeated prevalence survey conducted among community pharmacies in Lahore, a metropolitan city with a population of approximately 10 million people, from October to December 2017 using the World Health Organization (WHO) methodology for a global program on surveillance of antimicrobial consumption. Results: The total number of defined daily doses (DDDs) dispensed per patient ranged from 0.1 to 50.0. In most cases, two DDDs per patient were dispensed from pharmacies. Co-amoxiclav was the most commonly dispensed antibiotic with a total number of DDDs at 1018.15. Co-amoxiclav was followed by ciprofloxacin with a total number of 486.6 DDDs and azithromycin with a total number of 472.66 DDDs. The least consumed antibiotics were cefadroxil, cefotaxime, amikacin, and ofloxacin, with overall consumption highest in December. Conclusion: The study indicated high antibiotic usage among community pharmacies in Lahore, Pakistan particularly broad-spectrum antibiotics, which were mostly dispensed inappropriately. The National action plan of Pakistan on AMR should be implemented by policymakers including restrictions on the dispensing of antimicrobials

Mortality of emergency abdominal surgery in high-, middle- and low-income countries

Background: Surgical mortality data are collected routinely in high-income countries, yet virtually no low- or middle-income countries have outcome surveillance in place. The aim was prospectively to collect worldwide mortality data following emergency abdominal surgery, comparing findings across countries with a low, middle or high Human Development Index (HDI). Methods: This was a prospective, multicentre, cohort study. Self-selected hospitals performing emergency surgery submitted prespecified data for consecutive patients from at least one 2-week interval during July to December 2014. Postoperative mortality was analysed by hierarchical multivariable logistic regression. Results: Data were obtained for 10 745 patients from 357 centres in 58 countries; 6538 were from high-, 2889 from middle- and 1318 from low-HDI settings. The overall mortality rate was 1⋅6 per cent at 24 h (high 1⋅1 per cent, middle 1⋅9 per cent, low 3⋅4 per cent; P < 0⋅001), increasing to 5⋅4 per cent by 30 days (high 4⋅5 per cent, middle 6⋅0 per cent, low 8⋅6 per cent; P < 0⋅001). Of the 578 patients who died, 404 (69⋅9 per cent) did so between 24 h and 30 days following surgery (high 74⋅2 per cent, middle 68⋅8 per cent, low 60⋅5 per cent). After adjustment, 30-day mortality remained higher in middle-income (odds ratio (OR) 2⋅78, 95 per cent c.i. 1⋅84 to 4⋅20) and low-income (OR 2⋅97, 1⋅84 to 4⋅81) countries. Surgical safety checklist use was less frequent in low- and middle-income countries, but when used was associated with reduced mortality at 30 days. Conclusion: Mortality is three times higher in low- compared with high-HDI countries even when adjusted for prognostic factors. Patient safety factors may have an important role. Registration number: NCT02179112 (http://www.clinicaltrials.gov)

Some challenges in progressive control of livestock originated zoonotic diseases in Pakistan–a pilot survey

Objective: To document the recent livestock related practices and possible unhygienic ways of pathogen entry. Identification of the potential risk factors for the spread of infection is important to design an evidence-based disease control programme. Methods: Rapid assessment method was adopted and a purposive sample of 60 dairy farmers were interviewed. The following factors were noted for contributing in primary and secondary transmission of zoonotic infections: (i) persons who come in close contact with animals and their secretions, (ii) management strategies of farm animals (sheds and environment), (iii) management practices adopted at farms, (iv) small scale farmers and rural livestock production systems, (v) milk collection systems. Results: This research unveiled the certain routes of zoonotic disease transmission. Certain management practices, precautionary measures and strategies were the pivotal risk factors. Conclusions: The study emphasizes the need to educate the poor livestock keepers