Variational principle of fractional order generalized thermoelasticity

AbstractRecently, Youssef constructed a new theory of fractional order generalized thermoelasticity by taking into account the theory of heat conduction in deformable bodies, which depends upon the idea of the Riemann–Liouville fractional integral operator. In this paper, the variational theorem is obtained for the generalized thermoelasticity model for a homogeneous and isotropic body

Shear Behavior of High-Performance Reinforced Concrete Beams

High-performance concrete (HPC) is one of such new material that has a major improvement over conventional concrete; however, its behavior has to be fully understood. This paper presents experimental and numerical investigations in order to study the shear behavior of high-performance reinforced concrete beams. Four RC-HPC beams were tested experimentally in order to study the effect of the existence of web reinforcement and bar diameter of the web reinforcement as well as the amount of the tensile longitudinal steel bars on the shear behavior. Test results showed higher values of shear strength, stiffness, ductility and controlled the concrete cracking behavior due to the presence of stirrups. The ultimate load for beam having shear reinforcement of 6 mm diameter increased by about 16% compared to that of control beam BI-1 without shear reinforcement, while, that increase reached up to 34% for beam having 8 mm diameter web reinforcement. Besides, the numerical modeling enabled to capture satisfactory the behavior of HPC beam so that it can be used to study the effect of more parameters on the behavior of HPC beams

Shear Behavior of High-Performance Reinforced Concrete Beams

High-performance concrete (HPC) is one of such new material that has a major improvement over conventional concrete; however, its behavior has to be fully understood. This paper presents experimental and numerical investigations in order to study the shear behavior of high-performance reinforced concrete beams. Four RC-HPC beams were tested experimentally in order to study the effect of the existence of web reinforcement and bar diameter of the web reinforcement as well as the amount of the tensile longitudinal steel bars on the shear behavior. Test results showed higher values of shear strength, stiffness, ductility and controlled the concrete cracking behavior due to the presence of stirrups. The ultimate load for beam having shear reinforcement of 6 mm diameter increased by about 16% compared to that of control beam BI-1 without shear reinforcement, while, that increase reached up to 34% for beam having 8 mm diameter web reinforcement. Besides, the numerical modeling enabled to capture satisfactory the behavior of HPC beam so that it can be used to study the effect of more parameters on the behavior of HPC beams

Adomian’s decomposition method to modeling power functionally graded thermoelastic materials in heat transfer and thermal stress analysis

This work deals with an iteration method for numerical solving the problem of one-dimensional coupled thermoelasticity under given boundary conditions. This iteration based on the Adomian’s decomposition method. All the material properties have been considered variable on position with a power law. The numerical results have been calculated for different cases of the gradient parameter and the gradient index. The numerical results have been shown in figures. The gradient parameter and the gradient index have significant effects on the temperature increment, the strain, the stress, and the displacement

Predictors of Long-term Disability in Multiple Sclerosis: Real World Data from a Cohort of Egyptian Patients

Background: Specification of prognostic factors in multiple sclerosis (MS) is crucial for clinicians to guide therapeutic protocols. This study aimed to identify demographic, clinical, and radiological factors associated with disability on a long-term basis in relapsing-remitting MS (RRMS) and secondary progressive MS (SPMS).Methods: This was a retrospective study conducted on patients with RRMS and SPMS with a disease duration of at least 10 years. Demographic, clinical, and radiological parameters were collected from the medical records.Results: During the study period, 217 patients were recruited with a mean disease duration of 14.9 ± 4.6 (range: 10-35) years. Regression analysis revealed that age (B = 0.071, CI: 0.00-0.132, P = 0.025), male sex (B = –0.825, CI: –1.444 to –0.206, P = 0.009), duration between first 2 attacks (B = -0.007, CI: -0.015-0.000, P = 0.037), and involvement of pyramidal (B = 0.754, CI: 0.051-1.457, P = 0.036) or cerebellar domains (B = 1.355, CI: 0.542-2.168, P = 0.001) at disease onset were the only parameters that had an independent effect on EDSS.Conclusion: Predictors of long-term disability in our cohort were closely similar, but not typically identical to predictors reported in the literature. Age, male sex, short duration between first 2 relapses pyramidal and cerebellar affection were the strongest predictors of disability in patients with RRMS and SPMS

Genetic and morphological identification of some crabs from the Gulf of Suez, Northern Red Sea, Egypt

AbstractMost crab species inhabiting the Red Sea have not been characterized morphologically and genetically. In the current work, five different crab species were collected from the northern part of the Egyptian Red Sea. They were morphologically identified through description of colors, dentations of the carapace and shapes of chelipeds and pereiopods. They were also genetically characterized by the partial sequencing of the barcode region in the mitochondrial cytochrome oxidase subunit I (COI) gene, which is known to be hypervariable among different crab species. Morphological and genetic characterization identified the crab species as: Charybdis (Charybdis) hellerii (A. Milne-Edwards, 1867), Charybdis (Charybdis) natator (Herbst, 1794), Portunus (Portunus) pelagicus (Linnaeus, 1758), Liocarcinus corrugatus (Pennant, 1777), and Atergatis roseus (Rüppell, 1830). This is the first record of L. corrugatus in the Egyptian Red Sea, despite being previously recorded in the Indian and Atlantic Ocean as well as in the Mediterranean Sea. DNA barcoding with precise morphological identification was effective in characterizing the crab species collected from the Egyptian Red Sea water

Constitutive expression of SlMX1 gene improves fruit yield and quality, health-promoting compounds, fungal resistance and delays ripening in transgenic tomato plants

Tomato is one of the major economically domesticated crops, and it is extensively used in different ways and purposes worldwide. Cell metabolism is the central core of all the biological processes to sustain life including cell growth, differentiation, maintenance, and response to environmental stress. To evaluate how genetic engineering can improve tomato fruit metabolome, the transcriptomic and metabolomic datasets of two transgenic tomatoes (SlMX1 overexpression and RNAi lines) have been compared with wild-type. The combined results demonstrated that the constitutive expression of SlMX1 not only increased trichome formation, carotenoids, and terpenoids as has been stated in several studies, but has also up- and down-regulated the expression of multiple genes related to cell growth (cell wall turnover), primary (carbohydrates, vitamins, and phytohormones), and secondary (phenylpropanoids, carotenoids, and terpenoids) metabolism, cell signaling, and stress responses. These changes in gene expression due to the constitutive expression of SlMX1 promote the most important agroeconomic traits such as fruit yield and quality, biosynthesis of health-promoting phytochemicals (including phenolic acids, flavonoids, and anthocyanins), and finally, activate resistance to Botrytis cinerea and repress the expression of over-ripening-related genes, thus extending the fruit shelf-life. In conclusion, the traits improvement achieved by SlMX1 overexpression can be harnessed in molecular breeding programs to engineer fruit size and yield, induce health-promoting secondary metabolites, promote fungal resistance, and finally extend the fruit shelf-life.Xunta de Galicia | Ref. ED431E 2018/07Xunta de Galicia | Ref. ED431D2017/18Agencia Estatal de Investigación | Ref. EQC2019-006178-

Nephroprotective Role of Combined Sitagliptin and Oleuropein in Cisplatin-Induced Acute Kidney Injury: Regulation of SDF-1α/Nrf2/ HO-1 Axis and Autophagy

Background: Accumulating evidence proves that cisplatin, a widely used anticancer, causes acute kidney injury (AKI). Sitagliptin (Sita), a dipeptidyl peptidase-4 (DPP4) inhibitor, is a hypoglycemic agent that can promote tissue angiogenesis and cell survival. However, little is known about the nephroprotective effect of Sita in cisplatin-induced AKI especially its effect on SDF-1α, usually degraded by DPP4. Meanwhile, the olive oil component oleuropein (Ole) activates Nrf2/heme oxygenase-1 (HO-1) axis, which ultimately leads to SDF-1α activation. Herein, we studied the nephroprotective effects of combined Sita and Ole on oxidative stress and autophagy through SDF-1α/Nrf2/ HO-1 axis in cisplatin-induced AKI in rats. Methods: AKI was induced in vivo through single IP injection of cisplatin (7 mg/kg), while Sita (10 mg/kg) and Ole (16 mg/kg) were given separately and in combination for 7 days prior and 5 days after cisplatin injection. AKI was assessed through histopathological examination, measurement of serum creatinine and urea. Also, serum GLP-1, serum and kidney SDF-1α levels were measured by ELISA. LC3-II, P62, HO-1, Nrf2, and caspase-3 were investigated by western blotting. Results: Sita and Ole monotherapy and in combination accelerated kidney recovery as they suppress serum SDF-1α, serum BUN, creatinine and renal histopathological features. Each of Sita and Ole enhanced Nrf2/HO-1axis in renal tissues while only Sita enhanced renal SDF-1α. Sita and Ole monotherapy showed incompetent autophagy where the late steps of autophagy were incomplete. Combined treatment enhanced SDF-1α in kidney tissue which showed recovery through autophagy process. Conclusion: Sita and Ole show promising nephroprotective effects in cisplatin-induced AK

Influence of Number of Implants and Attachment Type on Stress Distribution in Mandibular Implant-Retained Overdentures: Finite Element Analysis

AIM: This study aimed to compare the stresses generated by using two or four root form dental implants supporting mandibular overdentures that were retained with ball and locator attachments.METHODS: Under ANSYS environment, four 3D finite element models were prepared. These models simulated complete overdentures supported by two or four implants with either ball or locator attachments as a connection mechanism. The models’ components were created by CAD/CAM package then were imported to ANSYS. Load of 100 N was applied at the right premolar/molar region vertically and at an oblique angle of 110° from lingual direction.RESULTS: Within the conditions of this research, in all cases, it was found that cortical and cancellous bone regions were the least to be stressed. Also, the ball attachment produced higher stresses.CONCLUSION: Caps deformation and stresses are negligible in cases of using locator attachment in comparison to ball attachments. This may indicate longer lifetime and less repair/maintenance operations in implant overdentures retained by locator attachments. Although the study revealed that bone was insensitive to a number of implants or attachment type, it may be recommended to use two implants in the canine region than using four, where the locator attachments were found to be better