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Herein, we describe the synthesis of novel piperidinyl thieno tetrahydroisoquinolines attached or fused to other new heterocycles. The diazotization of the previously synthesized pyrrolyl carbohydrazide 1 followed by several reactions with ethanol, aniline and heterocyclization after boiling in dry xylene under Curtius rearrangement conditions yielded the corresponding carbamate, phenyl urea and pyrazino derivatives 3–5. Furthermore, the condensation of 1 with various aromatic aldehydes and ethyl acetoacetate afforded the consistent Schiff's bases 6a-c and 7. The ring closure of the ethyl butanoate ester 7 furnished pyrazolyl compound 8 after heating in an ethanolic sodium ethoxide solution. Moreover, the nucleophilic addition of the carbohydrazide 1 to carbon disulfide in pyridine produced oxadiazolyl thione 9 which was reacted with ethyl chloroacetate to give ethyl sulfanyl acetate ester 10. The assignments of the chemical structures of these new heterocycles were confirmed by using elemental and spectral analysis. Alternatively, selected compounds were examined for antibacterial and antifungal screening. The results revealed highly promising influences against the nominated pathogenic strains.

New pyrazolothienopyrimidines were synthesized. The key intermediate 4-aminothieno[2,3-c]pyrazole-5-carbonitrile 1 was converted to the chloroacetyl amino derivative 2 followed by nucleophilic substitution and Dimorth rearrangement upon treatment with nitrogen nucleophiles to give the pyrimidinones 3a-c. Treatment of 3a with formaldehyde and with triethyl orthoformate afforded the respective tetracyclic derivatives 4 and 5. Condensation of the amino group in the o-aminocarbonitrile 1 with triethyl orthoformate followed by cycloaddition reaction with hydrazine led to the formation of pyrazolothienopyrimidine 8. Compound 8 was used as a synthetic precursor to heterocyclic compounds comprised of pyrazole, triazole, triazine, and triazepine derivatives.

In this study, heat transfer in a longitudinal rectangular fin with temperature-dependent thermal properties and internal heat generation is revisited. The advanced heat transfer models have been used to study the effects of thermo-geometric parameters, coefficient of heat transfer, and thermal conductivity parameters on the temperature distribution, heat transfer, and thermal performance of the longitudinal rectangular fin. It is shown that its governing nonlinear differential equation with proper boundary conditions is exactly solvable. With this aim, we reduce the order of the differential equation to first and then convert it into a total differential equation by multiplying by a convenient integrating factor. A full discussion and exact analytical solution in the implicit form is given for further physical interpretation and it is proved that three possible cases may occur: there is no solution to the problem, the solution is unique, or the solutions are dual, depending on the values of the parameters of the model.Key words: exact analytical solution, unique solution, dual solutions, heat transfer analysis, longitudinal fin, temperature-dependent thermal properties, temperature-dependent internal heat generation.Nous revisitons ici le probleme du transfert de chaleur dans une ailette rectangulaire longitudinale avec des proprietes thermiques dependantes de la temperature, avec generation interne de chaleur. Nous utilisons les modeles de pointe pour le transfert de chaleur afin d'etudier les effets des parametres thermo-geometriques, des coefficients de transfert de chaleur et des parametres de conductivite thermique sur la distribution de temperature, le transfert de chaleur et la performance thermique de l'ailette rectangulaire longitudinale. Nous montrons que son equation differentielle directrice non lineaire avec des conditions limites appropriees peut etre solutionnee de facon exacte. A cette fin, nous reduisons d'abord l'ordre de l'equation differentielle et la convertissons en une equation differentielle totale par multiplication avec un facteur d'integration approprie. Nous presentons une discussion complete avec une solution exacte sous forme implicite du probleme et nous prouvons qu'il n'y a que trois cas possibles : ou il n'y a pas de solution, ou la solution est unique, ou les solutions sont duales, dependant de la valeur des parametres du modele. [Traduit par la Redaction]Mots-cles : analyse de transfert de chaleur, ailette longitudinale, proprietes thermiques dependantes de la temperature, generation interne de chaleur dependante de la temperature, solution analytique exacte., 1. Introduction and problem formulationFins are very often encountered in many engineering applications to enhance heat transfer. Many researchers have assigned their works to the heat transfer treatment of the [...]

Sickle cell disease (SCD) is a genetically inherited hemolytic anemia increasingly appreciated as a chronic inflammatory condition and hypercoagulable state with high thrombotic risk. It is associated with disturbed immune phenotype and function and circulating microparticles (MPs) derived from multiple cell sources. This study was carried out to determine MPs profiles in patients with sickle cell anemia (either on hydroxyurea (HU) therapy or those with no disease-modifying therapy) and to compare these profiles with healthy children. Moreover, our study assesses the potential impact of HU on other aspects of circulating MPs. We performed a cross-sectional study on 30 pediatric patients with SCD divided by treatment into 2 groups (those receiving HU or no therapy) attending Hematology Clinic and 20 age-matched healthy children. The blood samples obtained were analyzed for MPs by flow cytometry. Sickle cell disease group with no therapy showed elevated levels of total, platelet, and erythroid MPs. In contrast, therapy with HU was associated with normalization of MPs. This study provided additional evidence that HU is an effective treatment option in pediatric patients with SCD, as it seems that it decreases the abnormally elevated MPs in those patients.

ONGOING climate change is leading to more extreme weather, which affects agriculture in various ways. In semi-arid regions of the world, and even some humid areas, drought stress is becoming more frequent. Prolonged drought periods lead to severe damages to cultivated plants, which impacts water and food resources. This review investigates how drought stress impacts plants and how management practices can be utilized to reduce the negative effects. Special attention is given to nano-farming where application of nanomaterials may ameliorate drought stress by increasing enzymatic antioxidants and decreasing generation of reactive oxygen species (ROS). Despite the promising results of nano-farming we conclude that further research is required, particularly to investigate potential negative effects, for example on nano-toxicity where particles can enter groundwater or into the food chain. Finally, drought stress is a complexed problem that affects all living organisms. A quick fix is not possible, but humankind needs to collaborate and work for a better future for all. [ABSTRACT FROM AUTHOR]

This research aimed to manufacture a simple fiber extraction machine. The machine prototype consisted of available raw materials. The beater cylinder is the most significant component in this machine. The electric motor of 0.75 kW was used to rotate the beater cylinder. The machine theory is based on the repeated rapid beating of the beaters on a slice-stem of banana. This beating simulated what labor does by using hand hammers to eliminate the juice and extract the fibers. The machine was tested under three rotational speeds of the beater cylinder 650, 750, and 850 rpm and using three beater cylinders with a different number of beaters 8, 10, and 12. The fibers produced by the machine were straight, of good quality, and not shredded, this was achieved in abundance when using the cylinder that has 10 beaters with 750 rpm rotational speeds of the beater cylinder. Thus, under these operating conditions, the extraction efficiency, the time required, and machine productivity were 88%, 40 min, and 8.6 kg h-1, respectively. The minimum value of the power required was 0.45 kW at the rotational speed of 650 rpm and using the eight beaters. While the maximum value of the power required was 0.64 kW at the rotational speed of 850 rpm and using the number of beaters 12. At the machine productivity of 8.6 kg h-1, the production cost will be 2.7 L.E. kg-1. While the costs of manual extraction of the fibers were 10 L.E. kg-1. [ABSTRACT FROM AUTHOR]

The current study investigated the protective potential of Azolla pinnate ethanolic extract (APE) against lead-induced hepatotoxicity in rats. Sixty male Wistar albino rats were randomly allocated into six groups (n = 10). The control group was orally administrated with saline. The second group received lead acetate (100 mg/kg body weight (BW) orally for 60 days). The third group was fed with APE (10 mg/kg BW orally for 60 days). The fourth group was administrated with lead acetate like the second group and APE like the third group, concomitantly, for 60 days. The fifth group was administrated with APE like the third group for 30 days, then orally administrated with the lead acetate like the second group for another 30 days. The sixth group was administrated with lead acetate like the second group for 30 days, then with APE like the third group for a further 30 days. Phytochemical analysis of APE indicated the presence of peonidin 3-O-glucoside cation, vitexin, rutin, thiamine, choline, tamarixetin, hyperoside, astragalin, and quercetin. The latter has been elucidated using one- and two-dimensional nuclear magnetic resonance (1D and 2D NMR) and liquid chromatography–mass spectrometry (LC–MS-MS). Lead acetate increased the serum levels of alanine and aspartate aminotransferases and that of urea, creatinine, tumor necrosis factor alpha, and interleukin 1β, hepatic tissue malondialdehyde contents, and caspase 3 protein expression, as well as altering the hepatic tissue architecture. However, it decreased the serum levels of interleukin 10 and glutathione (GSH) contents, and the activities of catalase and superoxide dismutase in hepatic tissue. In contrast, the administration of APE ameliorated the lead-induced alterations in liver function and structure, exemplifying the benefits of Azolla’s phytochemical contents. Collectively, A. pinnate extract is a protective and curative agent against lead-induced hepatotoxicity via its antioxidant, anti-inflammatory, and anti-apoptotic impacts.

Due to their continuous material variation and eliminating the mismatch stress field in the thickness direction, Functionally Graded Materials (FGMs) have found wide applications in aerospace and mechanical engineering. This article presents closed-form solution for thick functionally graded plate based on three-dimensional elasticity theory. To this end, first, the characteristic equation of FG plate is derived and general closedform is obtained analytically. Both positive and negative discriminant of characteristic equation is considered and solved. The presented method is validated with finite element results by considering isotropic thick plate. Several parametric studies are carried out to investigate the effect of geometric and material parameters. The aim of this research is to present analytical solution form for thick FG plate and work out the problem of inconsistency for corresponding displacements field. The presented solution can be used to examine accuracy of various plate theories such as first-order, third order shear deformation theories and other equivalent plate theories. [ABSTRACT FROM AUTHOR]