Nonlinear and sampled data control with application to power systems

Sampled data systems have come into practical importance for a variety of reasons. The earliest of these had primarily to do with economy of design. A more recent surge of interest was due to increase utilization of digital computers as controllers in feedback systems. This thesis contributes some control design for a class of nonlinear system exhibition linear output. The solution of several nonlinear control problems required the cancellation of some intrinsic dynamics (so-called zero dynamics) of the plant under feedback. It results that the so-dened control will ensure stability in closed-loop if and only if the dynamics to cancel are stable. What if those dynamics are unstable? Classical control strategies through inversion might solve the problem while making the closed loop system unstable. This thesis aims to introduce a solution for such a problem. The main idea behind our work is to stabilize the nonminimum phase system in continuous- time and undersampling using zero dynamics concept. The overall work in this thesis is divided into two parts. In Part I, we introduce a feedback control designs for the input-output stabilization and the Disturbance Decoupling problems of Single Input Single Output nonlinear systems. A case study is presented, to illustrate an engineering application of results. Part II illustrates the results obtained based on the Articial Intelligent Systems in power system machines. We note that even though the use of some of the AI techniques such as Fuzzy Logic and Neural Network does not require the computation of the model of the application, but it will still suer from some drawbacks especially regarding the implementation in practical applications. An alternative used approach is to use control techniques such as PID in the approximated linear model. This design is very well known to be used, but it does not take into account the non-linearity of the model. In fact, it seems that control design that is based on nonlinear control provide better performances

Assessment of Cardiac Enzymes in Obese Sudanese Subjects in Khartoum state

تقييم الانزييمات القلبية في البدناء موضوع هام تحري من قبل عدد من الباحثين في البلدان المختلفة .هذه المشكلة لم تتحري في السودان,الدراسة الحالية صممت لتحري الانزيمات القلبية في البدناء في ولاية الخرطوم. مجموعة من 50 ذكور واناث بدناء اختير بشكل عشوائي من مركزي في ولاية الخرطوم ( طلاب جامعة افريقيا العالمية وطلاب جامعة العلوم والتقانة ) طبقا للمعايير التالية : 1. مدي عمر من 18-25 2. البدناء بدون اي شروط شاملة 3. محيط خصر كل البدناء فحصت باستعمال دليل كتلة الجسم ,عمر وجنس وارتباط سريري كشفت النتائج ان الانزيمات القلبية مع متوسط وانحراف معياري (0.5 ±1.1) , والانتشار كان 96% علي اية حال ارتباط عمل بين دليل كتلة الجسم كان هناك جمعية هامة p= 0.029)) الارتباط الاخر عمل بين مستوي خسارة الارتباط السريرية ودليل كتلة الجسم p= 0.000))اخذ بعين الاعتبار نتائج هذه الدراسة التي توصي اصحاب الاختصاص بذيادة مستوي الوعي بين الافراد البدناء حول حالتهم الصحية لتحسين صحة القلب يجب اخذ النصح من المحترفين في هذا المجال

Antierosive Effect of Topical Fluorides: A Systematic Review and Meta-Analysis of In Situ Studies

BACKGROUND: The effectiveness of the application of topical fluorides in prevention of erosive tooth wear has been an issue of controversy in the literature. The objective of this systematic review was to assess in situ studies investigating the effects of using topical fluorides on prevention of erosive tooth wear MATERIAL AND METHODS: Two electronic databases PubMed/MEDLINE and Cochrane Central Register of Controlled Trials were searched. Eligibility criteria included in situ-controlled studies that assessed the effect of the erosive process without additional tooth brushing. The search involved English-written articles only. A total of 684 potentially relevant titles and abstracts were found after removal of duplicates, of which 22 full-text articles were selected. Seventeen studies were included in the qualitative synthesis of which 6 studies included in the meta-analysis. The following data were obtained for each study: authors, year of publication, country, study design, periods of study, duration, blinding, interventions (type/concentration/form), tooth substrate, location of the intraoral appliance, number of samples attached to each appliance, type of acidic media used for erosive challenge, duration of erosive challenge, subjects (number/age/sex), reported side effects -if any-, measuring device, amounts of tissue loss. RESULTS: The risk of bias of the included studies was assessed using the Cochrane Collaboration tool for assessing the risk of bias. A meta-analysis of the present study was performed using Comprehensive Meta-Analysis version 2.2.048 software. CONCLUSION: The use of oral hygiene products containing AmF/NaF/SnCl2 or NaF may be effective in the prevention of erosive tooth wear

CLINICAL SIGNIFICANCE OF PROCALCITONIN AND C-REACTIVE PROTEIN IN THE PREDICTION OF CARDIOVASCULAR COMPLICATIONS IN PATIENTS WITH TYPE 2 DIABETES MELLITUS

  Objective: This work was delineated to assess procalcitonin (PCT) and C-reactive protein (CRP) as prognostic markers for cardiovascular complication in type 2 diabetic patients.Methods: Forty diabetic patients without cardiovascular disease (CVD), 40 diabetic patients with CVD, and 20 healthy control counterparts were participated in this study. Serum PCT and CRP levels were assayed and correlated with metabolic parameters. Receiver operating characteristic (ROC) curve analysis was done for each biochemical marker.Results: The mean level of PCT was 707.17±99.19 ng/l in diabetic patients versus 881.30±123.56 ng/l for the cardio-diabetic patients (p<0.0001). The mean value of CRP was 34.43±17.27 mg/l in diabetic patients versus 50.32±20.19 mg/l for the cardio-diabetic patients (p=0.0003). PCT levels were significantly amplified in the cardio-diabetic patients with increasing CRP, triglycerides (TG), fasting blood glucose (FBG), and cholesterol (p=0.004, 0.0005, 0.002, and 0.01, respectively). CRP levels were significantly enhanced in the cardio-diabetic patients with increasing TG, FBG, cholesterol, and microalbumin (p=0.002, 0.047, 0.003, and 0.001 respectively). ROC curve analysis for PCT and CRP revealed that the area under curve (AUC) was 0.878 and 0.727, respectively. These findings indicate the good validity of the above biomarkers especially PCT as a prognostic marker for cardiovascular complication in type 2 diabetic patients.Conclusion: This study evidences the usefulness of measuring serum levels of PCT and CRP in diagnosis of cardiovascular complication in type 2 diabetic patients

Detection of Helicobacter pylori oipA and dupA genes among dyspeptic patients with chronic gastritis

Helicobacter pylori (H. pylori): is a microbe with wide genetic diversity that infects the stomach of most people in developing countries, leading to several clinical outcomes among different individuals such as gastritis, ulcers, or gastric cancer. Outer inflammatory protein A (oipA) and duodenal ulcer promoting (dupA) genes are among the possible virulence factors which determine the patient outcome. Aim: To detect oipA and dupA genes of H. pylori among dyspeptic Egyptian patients, and to investigate their correlation with the varying degrees of the associated chronic gastritis. Methods: The study enrolled 50 patients with dyspepsia, attending the Gastrointestinal Endoscopy unit of the Gastroenterology and Tropical Departments at Ain Shams University Hospital for upper gastrointestinal endoscopy, in the period between, June and, December 2019. Four antral gastric biopsies were taken from each patient for polymerase chain reaction assay to detect the virulence genes oipA, dupA, and cagA and for histopathological assessment. Results: Forty patients were H. pylori positive by histopathology and PCR. cagA, oipA, and dupA were identified in 6 (15%), 13 (32.5%), 9 (22.5%) of biopsies, respectively. Both cagA and oipA genes were highly significantly associated with increasing the severity of gastritis. Only oipA virulence gene showed a highly significant association with gastroduodenitis. There was a highly significant moderate association between cagA and oipA genes. Conclusion: oipA could be a virulence biomarker that serves a great value in predicting the progress of gastric mucosal damage in patients with chronic gastritis, and targeting antimicrobial therapy in those patients to prevent severe gastroduodenal diseases

Prevalencija i kardiovaskularni ishodi kod dijabetičke kardiomiopatije u egipatskih bolesnika s dijabetesom tipa 2: presječna multicentrična studija u bolničkom okružju

A multicenter study to evaluate the prevalence and cardiovascular outcomes of diabetic cardiomyopathy in type II diabetic patients. Two hundred participants with type II diabetes mellitus (DM) were included, while participants with coronary artery disease (CAD), valvular heart disease, or history of alcohol or drug abuse were excluded. Participants were subjected to history taking for age, gender, body mass index, smoking, dyslipidemia, medications, DM, Framingham diagnostic criteria of heart failure (HF), comprehensive clinical examination, 12 leads resting electrocardiogram, transthoracic echocardiography and one of the following laboratory investigations: glycated hemoglobin, random blood sugar, fasting blood sugar, or 2-hour 75-gram oral glucose tolerance test. The prevalence of diabetic cardiomyopathy versus (vs) no diabetic cardiomyopathy, left ventricular (LV) diastolic dysfunction grade II and III, systolic dysfunction, and hypertrophy in the study population was 23.0% vs 77.0%, 18.5%, 5.0%, and 8.0%, respectively. There was a highly significant difference between LV diastolic dysfunction grade II and III, systolic dysfunction, and hypertrophy in the diabetic cardiomyopathy group vs no diabetic cardiomyopathy group, with an absolute risk increase of 80%, 22%, and 35% in the diabetic cardiomyopathy group, respectively. There was a highly significant difference between the mean ejection fraction (EF) in the diabetic cardiomyopathy group vs the no diabetic cardiomyopathy group. The mean EF for the diabetic cardiomyopathy group was 5.5% lower than the mean EF for the no diabetic cardiomyopathy group. The prevalence of HF and pre-clinical HF in the diabetic cardiomyopathy group was 65% and 35%, respectively. The mean age for HF was 4.1 years older than the mean age for pre-clinical HF in the diabetic cardiomyopathy group. Smoking was significantly and strongly associated with HF vs pre-clinical HF in the diabetic cardiomyopathy group. Diabetic cardiomyopathy was prevalent in an Egyptian type II diabetic patient population and could be considered a primary myocardial disease predisposing to HF in type II DM.Cilj: Proveli smo multicentričnu studiju kako bismo odredili prevalenciju i kardiovaskularne ishode kod dijabetičke kardiomiopatije (DCM) u bolesnika s dijabetesom tipa 2. Metode: U istraživanje je bilo uključeno dvjesto ispitanika s dijabetesom tipa 2 (DM). Isključeni su ispitanici s koronarnom bolesti srca (CAD), valvularnom bolesti srca ili anamnestičkim podatcima o zlouporabi droga ili alkohola. Nakon anamnestičkih podataka utvrđeni su indeks tjelesne mase, učestalost pušenja, dislipidemije, DM-a, uporaba lijekova te su provedeni procjena dijagnostičkih kriterija zatajivanja srca (HF) prema Framinghamskoj studiji, klinički pregled, 12-kanaln elektrokardiogram u mirovanju, transtorakalna ehokardiografija te jedna od laboratorijskih varijabli: HbA1c, nasumične ili natašte izmjerene vrijednost glukoze u krvi ili rezultat dvosatnog testa oralne podnošljivosti glukoze. Rezultati: Prevalencija u usporedbi s odsutnošću DCM-a, dijastolička disfunkcija lijeve klijetke (LV) II. i III. stupnja, sistolička disfunkcija i hipertrofija u istraživanoj skupini iznosile su, redom: 23,0 % prema 77,0 %, 18,5 %, 5,0 % i 8,0 %. U skupini s DCMom postojala je značajna razlika u učestalosti dijastoličke disfunkcije LV-a II. i III. stupnja, sistoličke disfunkcije i hipertrofiji u usporedi sa skupinom ispitanika bez DCM-a, s apsolutnim povećanjem rizika u skupini s DCM-om za ta stanja od, redom, 80 %, 22 % i 35 %. Pronađena je i signifikantna razlika u prosječnoj vrijednosti ejekcijske frakcije (EF) između skupina s DCM-om i bez DCM-a. Prosječna EF u skupini s DCM-om bila je za 5,5 % niža nego u skupini bez DCM-a. Zastupljenost HF-a i pretkliničke HF u skupini s DCM-om iznosila je 65 % i 35 %. U skupni s DCM-om prosječna je dob kod HF-a bila 4 ,1 godinu viša nego prosječna dob za pretklinički HF. Pušenje je bilo izrazito i značajno povezano s HF-om u odnosu prema predkliničkom HF-u u skupni s DCM-om. Zaključci: DCM je bio zastupljen u egipatskih bolesnika s dijabetesom tipa 2 te se može smatrati primarnom miokardijalnom bolešću koja uzrokuje predispoziciju za HF kod dijabetesa tipa 2

Association of the serum chemerin level with the development of diabetic retinopathy in patients with type 1 diabetes mellitus

Background: In patients with type 2 diabetes mellitus, the development of diabetic retinopathy (DR) correlates positively with elevated serum chemerin levels. This study was aimed at investigating the probable association between the serum chemerin level and the development of DR in patients with type 1 diabetes mellitus (T1DM). Methods: In this cross-sectional study, we included Egyptians and classified them into four groups: group 1, including healthy individuals; group 2, including patients with T1DM without DR; group 3, including patients with T1DM with non-proliferative DR (NPDR); and group 4, including patients with T1DM with proliferative DR (PDR). The assessment included best-corrected distance visual acuity assessment, slit-lamp biomicroscopy, funduscopy, fundus fluorescein angiography, and macular ocular coherence tomography. Fasting blood samples were obtained from all participants to measure serum chemerin, glycated hemoglobin (HbA1c), total cholesterol, triglyceride, and creatinine levels. Serum chemerin levels were compared among the groups, and their correlations with age, duration of diabetes, HbA1c, total cholesterol, triglyceride, and creatinine levels were analyzed. Results: We recruited 209 participants, including 46 healthy individuals in group 1, 52 patients (T1DM and no DR) in group 2, 61 patients (T1DM and NPDR) in group 3, and 50 patients (T1DM and PDR) in group 4, with comparable mean ages and sex ratios among groups. The diabetes duration, body mass index, HbA1c, total cholesterol, triglyceride, and serum chemerin levels differed significantly among the groups (all P < 0.001), whereas the creatinine level did not (P > 0.05). The serum chemerin level was significantly higher in group 4 than in groups 3 and 2, in group 3 than in group 2, and in groups 3 and 4 than in group 1 (all P < 0.001). However, it was comparable between groups 1 and 2 (P > 0.05). It correlated with the duration of T1DM and HbA1c, total cholesterol, triglyceride, and creatinine levels but not with age. Conclusions: Patients with T1DM with DR showed higher serum chemerin levels than those with T1DM without DR or healthy individuals. Serum chemerin levels were higher in those with PDR than in those with NPDR. Thus, serum chemerin levels are a potential biomarker of the development and severity of DR in patients with T1DM. Nevertheless, future diagnostic accuracy studies are required to confirm these potential applications

Synthesis of new Norfloxacin-Tin complexes to mitigate the effect of ultraviolet-visible irradiation in polyvinyl chloride films

Polyvinyl chloride is used in the manufacturing of a wide range of products, but it is susceptible to degradation if exposed to high temperatures and sunlight. There is therefore a need to continuously explore the design, synthesis, and application of new and improved additives to reduce the photodegradation of polyvinyl chloride in harsh environments and for outdoor applications. This research investigates the use of new norfloxacin–tin complexes as additives to inhibit the photodegradation of polyvinyl chloride to make it last longer. Reactions between norfloxacin and substituted tin chlorides, in different molar ratios and in methanol under reflux conditions, gave the corresponding organotin complexes in high yields. The chemical structures of the synthesized complexes were established, and their effect on the photodegradation of polyvinyl chloride due to ultraviolet-visible irradiation was investigated. Norfloxacin–tin complexes were added to polyvinyl chloride at very low concentrations and homogenous thin films were made. The films were irradiated for a period of up to 300 h, and the damage that occurred was assessed using infrared spectroscopy, polymeric materials weight loss, depression in molecular weight, and surface inspection. The degree of photodegradation in the polymeric materials was much less in the blends containing norfloxacin–tin complexes compared to the case where no additives were used. The use of the additives leads to a reduction in photodegradation (e.g., a reduction in the formation of short-chain polymeric fragments, weight loss, average molecular weight depletion, and roughness factor) of irradiated polyvinyl chloride. The norfloxacin–tin complexes contain aromatic moieties (aryl and heterocycle), heteroatoms (nitrogen, oxygen, and fluorine), and an acidic center (tin atom). Therefore, they act as efficient photostabilizers by absorbing the ultraviolet radiation and scavenging hydrogen chloride, peroxides, and radical species, thereby slowing the photodegradation of polyvinyl chloride

Synthesis and Biological activity of 1,3-Thiazolylidenehydrazinylidene ethylpyridiniumbromide monohydrate, 1,3-Thiazolylidenehydraziniumbromide and 1,3-Thiazolylidenehydrazine derivatives

1,3-Thiazolylidenehydrazinylidene ethylpyridinium bromide monohydrate, 1,3-thiazolylidenehydrazinium bromide and 1,3-thiazolylidenehydrazine derivatives were synthesized by heterocyclization of 2-(1-substituted ethylidene) hydrazinecarbothioamides, characterized and screened for their anti-bacterial activities. The structures of synthesized compounds were established by spectroscopic (IR, 1H, 13C-NMR, Mass) and X-ray analyses

Foliar Applications of Bacillus subtilis HA1 Culture Filtrate Enhance Tomato Growth and Induce Systemic Resistance Against Tobacco mosaic virus Infection

The application of microbial products as natural biocontrol agents for inducing systemic resistance against plant viral infections represents a promising strategy for sustainable and eco-friendly agricultural applications. Under greenhouse conditions, the efficacy of the culture filtrate of Bacillus subtilis strain HA1 (Acc# OM286889) for protecting tomato plants from Tobacco mosaic virus (TMV) infection was assessed. The results showed that the dual foliar application of this culture filtrate (HA1-CF) 24 h before and 24 h after TMV inoculation was the most effective treatment for enhancing tomato plant development, with substantial improvements in shoot and root parameters. Furthermore, compared to non-treated plants, HA1-CF-treated tomato had a significant increase in total phenolic and flavonoid contents of up to 27% and 50%, respectively. In addition, a considerable increase in the activities of reactive oxygen species scavenging enzymes (PPO, SOD, and POX) and a significant decrease in non-enzymatic oxidative stress markers (H2O2 and MDA) were reported. In comparison to untreated control plants, all HA1-CF-treated plants showed a significant reduction in TMV accumulation in systemically infected tomato leaves, up to a 91% reduction at 15 dpi. The qRT-PCR results confirmed that HA1-CF stimulated the transcription of several defense-related tomato genes (PR-1, PAL, CHS, and HQT), pointing to their potential role in induced resistance against TMV. GC–MS analysis showed that phenol, 2,4-bis (1,1-dimethylethyl)-, Pyrrolo [1,2-a] pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl)- and eicosane are the primary ingredient compounds in the HA1-CF ethyl acetate extract, suggesting that these molecules take part in stimulating induced systemic resistance in tomato plants. Our results imply that HA1-CF is a potential resistance inducer to control plant viral infections, a plant growth promoter, and a source of bioactive compounds for sustainable disease management