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Islam Ali Abdel Raheem,1 Amro Abdul Razek,1 Abeer Abdelaziz Elgendy,1 Noha Mohamed Saleh,2 Mona Ibrahem Shaaban,3 Faten K Abd El-Hady4 1Department of Endodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt; 2Department of Pharmaceutics, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt; 3Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt; 4Chemistry of Natural and Microbial Products Department, National Research Centre, Giza, EgyptCorrespondence: Noha Mohamed SalehDepartment of Pharmaceutics, Faculty of Pharmacy, Mansoura University, Gomhoreyah Street, Mansoura 35516, EgyptTel/fax +2 050 2247496Email nunu_ramy@yahoo.comBackground: Propolis is a unique natural adhesive product collected by honeybees. It contains a diversity of bioactive compounds with reported functional properties such as antioxidants, antibacterial, antifungal, anti-inflammatory, antiviral and anticancer activity. Dental caries is a worldwide problem that caused by microbial growth usually progress from tooth enamel to the underlying pulpal tissues and root canal. This situation could be controlled by a sequence of steps to remove microorganisms and fill root canal with a suitable long-lasting root canal sealer. Unfortunately, leachable and degradation products of the currently used sealers compromised their antimicrobial activity by inflammatory modulation associated with irritation and toxicity of periapical tissues.Materials and methods: Hence, propolis was selected to be designed as a natural root canal sealer due to its amazing functional properties. Moreover, its handling properties were enhanced and potentiated by its incorporation in polymeric nanoparticles (NPs). Frist, propolis was collected, extracted and analyzed for its bioactive compounds. After that, propolis-loaded NPs of PLGA (ProE-loaded NPs) were developed and fully characterized regarding physicochemical properties, in vitro release and in vitro cytotoxicity. Then, root canal sealers were fabricated and assayed for their antimicrobial activity. Both cytotoxicity and antimicrobial activity were compared to those of a model sealer; AH Plus®.Results: The results revealed that spherical nanoscopic NPs with narrow size distribution were obtained. ProE-loaded NPs exhibited accepted entrapment efficiency (>80) and prolonged release. In vitro cytotoxicity study confirmed the safety of ProE-loaded NPs. Also, the developed sealers showed antimicrobial activity versus bacterial strains of Enterococcus faecalis and Streptococcus mutans and antifungal activity against Candida albicans.Conclusion: ProE-loaded NPs could be incorporated in and represented as a root canal sealer with prolonged release and enhanced cytocompatibility as well as antimicrobial activities.Keywords: propolis, sealer, polymeric nanoparticles, PLGA, in vitro cytotoxicity, antimicrobial activity

Selection of suitable glass composition for vitrification of high-level radioactive wastes (HLWs) is one of the major challenges in nuclear waste reprocessing. Atomic and molecular level understand...

Silver – polystyrene polyvinylpyrrolidone nanocomposites were synthesized by polymerization which was induced by γ-ray irradiation. Silver (Ag) nanoparticles were embedded in the polystyrene via subsequent reduction of Ag+ by γ-ray irradiation. Dispersion of Ag nanoparticles was achieved using polyvinylpyrrolidone as a dispersing agent. The morphology and particle size of the new silver/polystyrene/polyvinylpyrrolidone nanocomposite was studied by ultraviolet-visible spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, x-ray diffraction analysis and thermal gravimetric analysis. The prepared nanocomposites showed improved thermal stability. The TEM images demonstrate that well-dispersed Ag nanoparticles were embedded in polystyrene polyvinylpyrrolidone. According to TEM analysis, the size of the nanoparticles was found to be in the range of 15–45 nm. TEM images showed the favored shape of the nanoparticles as spherical. TGA indicated that the thermal stability of polystyrene is enhanced when loaded with Ag nanoparticles and this is clear from the data obtained and the values of the activation energy. This method constitutes a promising way to prepare versatile inorganic-organic polymer nanocomposites. The applied method is both simple and inexpensive and does not use toxic chemicals, unlike other chemical methods.

Interfacial polymerization of trimesoyl chloride (TMC) and 1,3- phenylene diamine (MPD) was simultaneously combined with the in-situ formation of TiO2 from TiCl4 using urea. The titania-polyamide nanocomposite (TPN) was characterized by using X-ray diffraction, Fourier transform infrared spectroscopy, N2-physisorption analysis and a scanning electron microscope equipped with energy-dispersive X-ray spectroscopy. The TPN was evaluated as an adsorbent for the removal of dyes. It showed high efficiency for the removal of several dyes in the order: methylene blue > bromo phenol > methyl orange > congo red > rhodamine B. The dosage, contact time, and temperature which are the main factors that affect adsorption efficiency, were optimized. Among isotherm models, the experimental adsorption results fitted well with the Langmuir model with a maximum adsorption capacity of 43 mg/g. Kinetic experiments were conducted to describe the equilibrium rate. The model of the pseudo-second-order adequately fitted the experimental data with a correlation coefficient R2 of 0.998. Thermodynamic studies were performed to evaluate the performance of TPN at various temperatures. Thus, parameters including free energy (ΔG°), enthalpy (ΔH°) and the entropy (ΔS°) were calculated. The influence of the interference on adsorption was investigated in the presence of metals including Ni, Hg, As, Cu, and Cr. Interestingly, with ≈100% removal of the dye, TPN showed a rapid simultaneous uptake of the toxic metals as well.

Structural systematics is a multidisciplinary approach in structural science that involves a comprehensive analysis of structurally related compounds. The main concept of structural systematics is the comparison of chemical structure data, usually derived from single crystal or X-ray powder diffraction, with physical properties of structurally similar compounds (salts, complexes and small organic molecules). From this idea we have developed in Chapter 2, a 2×6 isomer grid of difluorobenzamides (F2-xx) and (xx-F2) as investigated by integrating crystal structure analyses, gas phase calculations and conformational analyses. All isomers aggregate via N–H⋯O=C intermolecular interactions and usually in combination with intermolecular C– H⋯O/F/π interactions and often with F⋯F contacts. Expanding benzamide derivatives to di-amides increases the possibility of pharmacological activities. The X-DIP compounds were therefore synthesised and characterized by spectroscopic techniques and X-ray diffraction as detailed in Chapter 3. Halogens (X) influence the aggregation in crystal structures by varying interactions especially halogen bonding. These compounds were further reacted to form two novel groups of amideimide and di-amide isomers. Substitution of the di-amides with ethyl esters at the ortho-, meta-, and para- positions provide the x-Est-DIP and x-Est-PYR derivatives, in Chapter 4, that potentially increases the number of interaction sites and also enforces a change in the molecular geometry. The pyridine (2/3/4-Est-PYR) derivatives typically bind to water molecules by strong N–H⋯O hydrogen bonding interactions. From this research, substituted pyridine/pyrimidine rings in the (x-N2)2-PYR diamide system are explored in Chapter 5. Pyridines and pyrimidines are substantial precursors of many biomolecules and have chemical and biological applications. The presence of water molecules tends to impart quite different chemical and physical properties and their crystal structures display several interesting features. Finally, di-imide macrocycle products combining 3 or 4 (x-IO3 and x-IO4) rings are discussed in Chapter 6 in order to maximise the highest possible yields and develop the most effective synthetic strategies and procedures.

In this study, the current state of agricultural enterprises and production activities in Bulancak District of Giresun province was examined and some suggestions was made. Data were collected from 134 enterprises selected from ten villages using stratified random sampling in the 2016-2017 production period. The data were collected using the survey method. The enterprises were divided into three groups based on the frequency distribution of the size of land that they had. According to the results, Groups 1, 2, and 3 had an average of 5.02 decare, 15.76 decare, and 45.80 decare agricultural lands per enterprise, respectively. The overall average was 24.29 decare. In all groups, most of the agricultural lands were hazelnut gardens, followed by fruits, field crops, vegetables, meadow-pasture, and shrubland-woodland. The greatest problems faced by the enterprises during agricultural activities were low selling price, expensive agricultural inputs, disease damages, low yield, and scarce labor. The enterprises stated that they tried to obtain more information, consulted with agricultural provincial/district officials, became members of cooperatives/unions, took loans to improve their agricultural activities. They stated that they solved agricultural problems by consulting with knowledgeable farmers, friends/colleagues, and agricultural organization experts. In terms of increasing yield and quality and reducing production costs, it is recommended to apply sufficient business size and modern agricultural techniques. In addition, the importance of the farmer and food production, which has gained more value recently, is also emphasized., Bu çalışmada, Giresun ili Bulancak ilçesinde tarımsal işletmelerin ve üretim faaliyetlerinin mevcut durumu incelenmiş ve öneriler yapılmıştır. Araştırmada kullanılan veriler, 2016-2017 üretim döneminde 10 köyden tabakalı tesadüfi örnekleme yöntemi ile seçilen 134 işletmeden anket yöntemi ile elde edilmiştir. İşletmeler sahip oldukları arazi büyüklüklerinin frekans dağılımına göre üç gruba ayrılmıştır. Araştırma sonuçlarına göre; işletme başına düşen ortalama işletme arazisi 1. grupta 5,02 da, 2. grupta 15,76 da, 3. grupta 45,80 da ve işletme genel ortalamasında ise 24,29 da olarak bulunmuştur. Her üç grupta da tarım arazilerinin çok büyük bir kısmını fındık bahçeleri oluşturmaktadır. Fındık arazilerini sırasıyla diğer meyveler, tarla bitkileri, sebzeler, çayır-mera ve çalılık-ağaçlık arazi izlemektedir. İşletmelerde tarım faaliyetlerinde karşılaşılan en önemli kısıtlar sırasıyla; düşük satış fiyatı, pahalı tarım girdileri, hastalık, düşük verim ve işgücü yetersizliği şeklinde sıralanmaktadır. Tarım faaliyetlerini geliştirmek için işletmeler daha fazla bilgilenmeye çalıştıklarını, il/ilçe tarım görevlilerine danıştıklarını, kooperatife/birliğe üye olduklarını ve kredi aldıklarını belirtmişlerdir. İşletmeler tarımla ilgili sorunlarını bilgili çiftçilere, arkadaşlarına/meslektaşlarına, tarım teşkilatı uzmanlarına danışarak çözmektedirler. Verim ve kalitenin artırması ve üretim maliyetlerinin düşürülmesi bakımından yeter işletme büyüklüğü ve modern tarım tekniklerinin yerinde ve zamanında uygulanması önerilmektedir. Ayrıca son zamanlarda daha da değer kazanan çiftçilik mesleği ve gıda üretiminin önemi de vurgulanmaktadır.

Objectives:Patients with impaired renal functions have a variable risk of morbidity and mortality in cardiovascular surgery. Poor outcome was reported among patients who underwent valve surgery. Current study is presumed to compare the early outcomes of patients having different degrees of impaired renal functions and undergoing mitral valve replacement surgery. Methods:135 patients were admitted into the three highly specialized centers in Cairo and Ismailia–Egypt between Dec.2018 and Jan.2020 Preoperative, intraoperative and early post-operative data were recorded. Impairment may present as one of these strata: early reversible (G1-2 included strata 1 & 2 kidney disease patients), moderate G3-4 included strata 3 & 4 kidney disease patients) or advanced irreversible renal damage. (The 5th stratum or G5-KD included end stage renal disease patients undergoing 4-hour hemodialysis sessions, three times a week, with bicarbonate dialysate). We correlated outcome among each stratum with cardiac and renal functions in that stratum. Results:The more is the impairment of renal functions at any peri- operative stage, the longer is the need for prolonged mechanical ventilation and the longer is the hospital stay. We found that levels of serum creatinine were significantly increased postoperatively Also, the more is the reversibility of the renal impairment, even by renal dialysis, the much better is the outcome (P=.0019). We also found insignificant difference between different strata of irreversible renal impairment in the early outcome of the prosthetic mitral valve replacement surgery. The early reversible damage can be repaired peri-operatively. Conclusions:Prosthetic mitral valve replacement among patients with different degrees of impaired renal functions is not only feasible but also it does not seem to add any more deterioration into renal function. Prolonged mechanical ventilation and hospital stay are the only drawbacks of irreversibly impaired renal damage by dialysis or renal transplant.

Bu çalışma, 2019 yılında, Ordu Üniversitesi Ziraat Fakültesi Bahçe Bitkileri Bölümü Doku Kültürü laboratuvarında yürütülmüştür. Çalışmada eksplant olarak Çakıldak çeşidinin aktif büyüme dönemindeki sürgün uçları kullanılmıştır. Eksplantların bir kısmı %70 etil alkolde 10 sn süre ile bekletilmiş, diğer yarısına ise etil alkol uygulanmamıştır. Etil alkol uygulanmış ve uygulanmamış tüm eksplantlar, farklı dozlarda sodyum hipoklorid (% 0, % 5, % 10 ve % 15) çözeltilerinde farklı sürelerde (0, 10, 15 ve 20 dakika) bekletilerek yüzey sterilizasyonları yapılmıştır. Deneme kapsamında uygulamaların karşılaştırılması amacıyla kararma oranı (%), enfeksiyon oranı (%), sağlıklı gelişen eksplant oranı (%) özellikleri incelenmiştir.Eksplantların yüzey sterilizasyonu amacıyla ilk olarak % 70 etil alkolde 10 sn süre ile bekletme ve ardından % 5 dozundaki sodyum hipoklorid çözeltisinde 15 dakika bekletme uygulamaları tavsiye edilebilir.

The current study was aimed to investigate the effect of different fertilization and biostimulant treatments on growth and flowering of Gerbera (Gerbera iamesonii cv. Jaguar Yellow) plant under unheated plastic greenhouse conditions. This study was carried out for two successive seasons of 2016/2017 and 2017/2018 at the farm of the Arid lands Agriculture graduated studies and Research Institute (ALARI), Shobra Elkheima area, Qalyobia governorate, Egypt. The experiment were laid out in a completely randomized design (CRD) with 3 replications, and the end results have been subjected to analysis of variance (ANOVA). Freshly extracted gerbera seedling have been planted into pots filled with peatmoss + sand (1:1), peatmoss + sand + vermicompost (1:1:1), peatmoss + sand + compost (1:1:1) with or without 250ml of Azotobacter + Azospirllum mixture, as biostimulant, and slow-release NPK (4.2g) or fast-release NPK (2.5g) fertilizers to each plant, to determine the effect of fertilizer, biostimulant and growing medium types on the production of potted gerbera. Growth and flowering characteristics were measured. Results indicated that medium combination of sand + vermicompost + peatmoss (1:1:1) with biostimulant, regardless of the fertilizer type, gave significantly increased results in all measurements, compared to all other combinations. Plants grown in medium supplemented with biostimulant and fast-release fertilizer, gave flowers with good qualities While the medium combination sand + vermicompost + peatmoss (1:1:1) with biostimulant in combination with either one of NPK mineral fertilizers (fast-release fertilizer and slow release fertilizer) gave significantly increased results in most parameters, shown in higher total vegetarian and quality when combined with slow release fertilizer than fast-release fertilizer. Under this treatment, plant length was (28.2 cm), number of leaves per plant was (24.8), stem diameter was (3.7 mm), fresh weight (47.9 g), seedings dry weight (12.5g), length of the longest tap root was (19.8 cm), diameter of tap root (2.9 mm), number of secondary roots (40.7), root/shoot ratio (2.57), Leaf greenness "SPAD 59", and the highest number of daughter plants (5.3/plant). These records were all significantly higher than other treatments

In this paper, development and experimental evaluations of high frequency transformer connected to the full-bridge, phase-shift power converter are presented. This power converter is considered for power applications which have low input voltage and high current sources as a fuel cell generation system, telecommunication power plants, front stage of automotive AC power supplies and plasma generators. The main advantages of using this transformer in DC-DC converter are low size, low weight, low cost, and high performance. High-frequency transformer made of planar principle eliminates some shortcoming of old-fashioned wire wound and thus planar magnetics become increasingly popular in our life. The main constructor of planar transformer is PCB windings with core yield many advantages over the conventional magnetics. This paper discusses the effect of the magnetizing inductance of the planar transformer linked with DC-DC converter and distribution current in secondary windings. This power converter's operating principle is based on the quasi-resonant soft-switching circuit topology using high-frequency transformer parasitic parameters and lossless snubbing capacitors and its power is regulated using secondary-side phase-shifted controlled technology. Simulation and experimental testing of the performance of the proposed soft-switching DC-DC power converter using two new types of high-frequency transformers designed especially for this converter with different magnetizing inductances.

In today's highly competitive market, manufacturing companies compete in order to achieve a superior customer response and significant cost savings. From this perspective, the lexicographic bottleneck assembly line balancing problem is recently introduced to the literature in order to implement more reliable assembly lines through increasing the quality of balance among the most heavily loaded workstations. The purpose of this work is to integrate the advantage of the flexible assembly lines through considering variety of resource alternatives for executing each task with the concept of the lexicographic bottleneck assembly line balancing. Accordingly, a new mathematical model called Lexicographic Bottleneck Mixed-Model Flexible Assembly Line Balancing Problem (LB-MFALBP) is formalized for the first time in the literature. In addition, an exact solution is proposed for optimally solving small instances using a commercial solver in a reasonable computation time.

Polyamide branches grafted onto carbon microspheres (CMS) was successfully synthesized by interfacial polymerization of 1,3,5-trimesoyl chloride and 1,3-phenylene diamine in situ with CMS. The obtained CMS-polyamide was characterized by Fourier transform infrared spectroscopy, thermogravimetric analyzer, scanning electron microscopy and Energy-dispersive X-ray spectroscopy. The sorption efficiency of the CMS-polyamide was evaluated by using rhodamine B (RhB) dye-polluted solutions. It exhibited excellent adsorption performance for the removal of RhB with adsorption capacity of 19.9 mg/g. The pseudo-second-order equation and the Langmuir model exhibited a good correlation with the adsorption kinetics and isotherm data with R2 of >0.99. Tests of adsorption/desorption were performed, and the results showed that dye loaded CMS-polyamide could be regenerated (97%) using acetone. Possible adsorption mechanisms have been proposed, where electrostatic attraction, π-π stacking interactions and complexation interaction with metal dominate the adsorption of RhB. The excellent removal rate (≈100%) of RhB, even in the presence of heavy metals (Pb, Cd, Hg, Cr, Ni, and Cu) in single and binary systems, endowed the CMS-polyamide with the potential for applications in water treatment.

The current paper investigates the problem of structural progressive collapse.A two-bay small scale reinforced concrete frame has been casted without the intermediate column and dynamically-loaded until failure in order to investigate its behavior and strength under column loss condition. During the test, deflection, cracking, longitudinal strains in both steel bars and concrete, ultimate loads and mode of failure have been monitored. Additionally, an F.E model, using Abaqus 6.13 program is presented.In the numerical model, strain rate effects have been considered. The tested frame was prepared and casted in the reinforced concrete laboratory, faculty of Engineering, Menoufia University while the testing process took place in reinforced concrete laboratory, faculty of Engineering, Tanta University.