184 research outputs found

    DEVELOPMENT OF EFFICIENT CLOUD POINT EXTRACTION METHOD FOR PRECONCENRATION AND SPECTROPHOTOMETRIC DETERMINATION OF NICKEL IN WATER SAMPLES USING 2-(BENZOTHIAZOLYLZAO)ORCINOL

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    Objective: Efficient cloud point extraction (CPE) methodology was developed for pre concentration of trace nickel in water samples prior to their determination by spectrophotometry.Methods: The method is based on the reaction of nickel with 2-(benzothiazolyl azo) orcinol reagent (BTAO) at pH 7.0 and micelle-mediated extraction using the nonionic surfactant Triton X-114 medium.Results: The surfactant-rich phase was diluted with methanol and the nickel content was determined at 558 nm. The optimum conditions (e. g. pH, reagent and surfactant concentrations, and temperature and centrifugation times) were evaluated and optimized. The proposed CPE method showed linear calibration within the range 10–250 ng/ml of nickel and the limit of detection of the method was 2.0 ng/ml with a pre concentration factor of  50. The relative standard deviation (RSD) and relative error were found to be 1.10% (N = 6). The interference effect of some cations and anions was also studied.Conclusion: The method was applied to the determination of nickel in water samples with a recovery from the spiked samples in the range of 95.85–98.50%. Â

    Periodontal Management of Non Healing Endodontic Lesion– A Case Report

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    The fact that the periodontium is anatomically interrelated with the dental pulp by virtue of apical foramina and lateral canals creates pathways for exchange of noxious agents between the two tissue compartments when either or both of the tissues are diseased. Proper diagnosis of the various disorders affecting the periodontium and the pulp is important to exclude unnecessary and even detrimental treatment. This is a clinical case report of an enododontic–periodontic lesion in relation to lower left central incisor. Root canal treatment has been done with the respected tooth six months ago, but the lesion showed no sign of healing resulting in draining sinus and increasing pocket depth. Radiographic examination revealed over-obturation of gutta-percha with peri-radicular pathology. Periodontal flap surgery was performed and the defect was filled with bone graft mixed with Platelet rich plasma (PRP) and covered by platelet rich fibrin (PRF). Patient reviewed for six months which showed uneventful healing and no recurrence of the lesion

    Surface-roughness improvement in ultrasonically assisted turning

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    Ultrasonically assisted machining is a hybrid technique based on superimposition of ultrasonic vibration on a movement of a cutting tool. Such vibration with relatively small amplitude - below 20 microns - changes dramatically the response of a machined material to a cutting process. As a result, a significant - in excess of 80% in turning of aerospace superalloys - reduction of average cutting forces is observed together with improvement of surface roughness. The paper presents results of analysis of the effect of ultrasonically assisted turning (UAT) on surface roughness (using a broad range of parameters) for a broad range of metals and alloys - from copper, aluminium and stainless steel to Ni- And Ti-based alloys. The effect of machining parameters for both conventional turning and UAT was investigated to provide an optimum range for each material and its relation to surface roughness

    Seasonal Variation in Chemical Composition, Ruminal Fermentation, and Biological Characteristics of Paulownia shan tong: In Vitro Potential Use by Sheep and Goats

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    [EN] This study was conducted to determine the seasonal variation (two seasonal harvests during winter and spring) in some chemical and biochemical characteristics of Paulownia shan tong leaves. To achieve this, we analyzed the chemical composition in terms of dry matter (DM), organic matter (OM), crude protein (CP), cell-wall content (neutral detergent fiber (NDF)), acid detergent fiber (ADF), acid detergent lignin (ADL), and lipids. The phenolic compounds (PC) and antioxidant activity (AA) of the leaves were also determined. In vitro gas production (GP) and nutrient degradability were evaluated using two ruminal-content donors (sheep and goats). Higher (p < 0.05) antioxidant activities were observed in the winter harvest of P. shan tong, while higher concentrations of OM (90.5%), lipids (3.02%), NDF (69.7%), ADF (54.8%), ADL (35.4%), total flavonoids (0.45 mg catechin equivalents/mg DM), and total phenolics (2.52 mg gallic acid equivalents/mg DM) were observed in the spring harvest. Higher asymptotic GP and rate of GP (p < 0.05) were observed when the leaves were incubated with rumen liquor of goats compared to sheep; however, higher (p < 0.05) lag time of GP and half-time of GP were observed with rumen liquor from sheep. Moreover, higher asymptotic GP, rate of GP, and half-time of GP were observed with the winter harvest of P. shan tong. Higher (p < 0.001) metabolizable energy, OM degradability, and microbial protein supplies were obtained when the leaves were incubated with rumen fluids from goats and from the winter harvest of P. shan tong compared to the spring harvest. In conclusion, based on the chemical composition and the kinetics of in vitro gas production, P. shan tong leaves seem to be characterized by a good nutritive value and could be considered as an alternative feed resource for ruminantsSIThis research received no external fundin

    Diatomite alleviates the adverse effects of salinity stress on growth and yield of Stevia rebaudiana

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    ABSTRACT The present study was planned to investigate the role of diatomitein salt tolerance of Stevia rebaudiana using pot experimental. Diatomite increased the growth characters of plants, hence resulted in higher yields. In contrast, the seawater treatments alone significantly decreased these parameters in both seasons. While, treating Stevia rebaudianaplants with diatomite prior to salinity stress decreased the detrimental effectof salt stress on growth and yield.The Esterase isoenzymesprofiles has indicated that salinity, diatomite and their combinations has caused biochemical changes in Steviar. plants. On the other hand, saline water irrigation decreased Rebaudioside A concentration at the second harvest as estimated by HPLC analysis in both seasons .The effect of the interaction between salinity and diatomite was the mosteffective treatments for Rebaudioside A when Stevia rebaudianaplants treated by salt concentration 4000 ppm and 2.5 g/kgsoil diatomite

    A Novel Quinazoline Inhibits Hsp90 Protein, EGFR and Induces Apoptosis in Leukemia Cells

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    The objective of the first part of this study was to investigate the Hsp90 protein possible activ ity of a novel quinazoline Her2/ EGFR inhibitor (Co mpound No. 1: 4-(2-(4-Oxo-2-thio xo-1,4-d ihydroquinazolin-3(2H)yl)ethyl)benzenesulfonamide) p reviously synthesized by a collaborating group. Heat shock protein 90 (Hsp90) has a central ro le in regulation of several client proteins involved in cancers [1,2]. Several Hsp90 inhibitors of the natural or synthetic origin d isplayed potent anticancer activity [3,4]. Accordingly, Hsp90 emerged as an attractive target in the design of anticancer agents. To evaluate the binding mode of compound No. 1 into the ATPase site of Hsp90, a co mparative mo lecular docking study was performed using AutoDock 4.2. The results of this studywas compared with that of the co-crystallized ligand (ATI-13387X, Onalespib). The energy minimization process of the chemical structures of No. 1 was done following our previous report [5]. The results of the docking study revealed that No. 1 fit n icely into the ATPase site, and it displayed a binding free energy (Gb) of-7.21 kcal/ mo l and inhibition constant (Ki) of 5.19 µM to Hsp90, co mpared to Gb of-7.90 kcal/ mol and Ki of 1.62 µM for ATI-13387X. Furthermore, to confirm this result, the surface plasmon resonance (SPR) was devised to test the Hsp90 inhibition activity of No.1, wh ich was 51 nM co mpared to Rad icico l and 17AA G (1.8 nM, and 360 nM; respectively). Overall, co mpound No. 1 exh ibited pro mising Hsp90 inhib iting activity. The second part of the study focused on the effect of No. 1, Dinaciclib and their co mbinationsin HL-60 leukemia cells. The comb ination showed synergistic EGFR inhib ition effect in HL-60 cells. Moreover, No. 1, Dinaciclib and their combination caused a significant increase in the Sub-G1 co mpared to control and doxorubicin (24h), at the expense of S and G2/M cell cycle phases. Cyclin D3, was consequently inhibited by each of the two drugs, and synergistically by their comb ination in HL-60 cells. Furthermore, each of the two drugs downregulated Survivin, wh ich was synergistically inhib ited by the co mbination. In conclusion, co mpound No.1, Dinaciclib and their comb inations showed synergestic EGFR inhibit ion; and pro-apoptoticeffect in HL-60 cells.This project was funded by the deanship of scientific research, Umm Alqura University, KSA (DSR: 15-M ED-3-1-0060). Keywords: Novel quinazoline EGFR inhi bi tor, Hs p90 protein, Leukemi a cells

    Molecular characteristics and zoonotic potential of enteric protists in domestic dogs and cats in Egypt

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    Introduction: Domestic dogs and cats can be a source of human infection by a wide diversity of zoonotic pathogens including parasites. Genotyping and subtyping tools are useful in assessing the true public health relevance of canine and feline infections by these pathogens. This study investigated the occurrence, genetic diversity, and zoonotic potential of common diarrhea-causing enteric protist parasites in household dogs and cats in Egypt, a country where this information is particularly scarce. Methods: In this prospective, cross-sectional study a total of 352 individual fecal samples were collected from dogs (n = 218) and cats (n = 134) in three Egyptian governorates (Dakahlia, Gharbeya, and Giza) during July-December 2021. Detection and identification of Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi, and Blastocystis sp. were carried out by PCR and Sanger sequencing. Basic epidemiological variables (geographical origin, sex, age, and breed) were examined for association with occurrence of infection by enteric protists. Results and discussion: The overall prevalence rates of Cryptosporidium spp. and G. duodenalis were 1.8% (95% CI: 0.5-4.6) and 38.5% (95% CI: 32.0-45.3), respectively, in dogs, and 6.0% (95% CI: 2.6-11.4) and 32.1% (95% CI: 24.3-40.7), respectively, in cats. All canine and feline fecal samples analyzed tested negative for E. bieneusi and Blastocystis sp. Dogs from Giza governorate and cats from Dakahlia governorate were at higher risk of infection by Cryptosporidium spp. (p = 0.0006) and G. duodenalis (p = 0.00001), respectively. Sequence analyses identified host-adapted Cryptosporidium canis (n = 4, one of them belonging to novel subtype XXe2) and G. duodenalis assemblages C (n = 1) and D (n = 3) in dogs. In cats the zoonotic C. parvum (n = 5) was more prevalent than host-adapted C. felis (n = 1). Household dogs had a limited (but not negligible) role as source of human giardiasis and cryptosporidiosis, but the unexpected high frequency of zoonotic C. parvum in domestic cats might be a public health concern. This is the first molecular-based description of Cryptosporidium spp. infections in cats in the African continent to date. Molecular epidemiological data provided here can assist health authorities and policy makers in designing and implementing effective campaigns to minimize the transmission of enteric protists in Egypt.This study was partially funded by the Health Institute Carlos III (ISCIII), Spanish Ministry of Economy and Competitiveness under project PI19CIII/00029. This study was supported by Researchers Supporting Project number (RSPD2023R655), King Saud University, Riyadh, Saudi ArabiaS

    LOCUS OF CONTROL THEORY IN TREATING TOURIST BEHAVIOR: THE THEORY ROOTS AND RESEARCH DIRECTION IN DESTINATION BRANDING FIELD

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    We aim to shed light on this issue by reviewing the roots and development of the locus of control theory. Moreover, we will introduce how we can use this development, in theory, to provide a new research direction in the tourism service field. A theory-based review was conducted to investigate the locus of control theory roots and its potential implications in the tourism industry using the Australian Business Deans Council (ABDC) list to explore the current literature. We followed the PRISMA methodology to collect the data from the Scopus database as well as Google Scholar and ResearchGate. The study found that the locus of control theory has its roots in social psychology and has been developed over the years to explain individual differences in behavior and decision-making. In the tourism service field, we found that understanding the locus of control can help service providers tailor their services to meet the needs and expectations of different types of tourists. This will contribute to attribution literature in psychological aspects and tourism literature with a deep understanding of how tourists behave and interpret differently
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