Behavior of RC Wide Beams under Eccentric Loading

Wide beams are one of the widely used structural elements in RC buildings due to the many special features that characterize them. The main objective of this research is to investigate the behavior of wide shallow beams under the effect of eccentric loading acting along their cross sections. To achieve that, an experimental program that consisted of seven wide beams was conducted. All beams were loaded using two concentrated loads at their middle third where the main parameters considered were: the magnitude of the load eccentricity, the longitudinal spacing between shear reinforcement, and the arrangement of the longitudinal reinforcement. Following that, a finite element analysis was performed where the analytical model used was first verified using the data from the experimental program. The results from both the experimental and analytical programs were in good agreement. Then, the finite element analysis was extended through a parametric study where other variables were studies such as the compressive strength of concrete, the transverse spacing between stirrups and the longitudinal reinforcement ratio. The results showed that the value of the load eccentricity, spacing between shear reinforcement, the arrangement of the main reinforcement along the beam cross section, and the compressive strength of concrete significantly affected the torsional resistance of shallow wide beams. Conclusions and recommendations are presented which can be useful for future researchers. Doi: 10.28991/cej-2021-03091766 Full Text: PD

“Sidewalk” as a Realm of Users’ Interactions: simulating pedestrians’ densities at a commercial street in Cairo City

During the last four decades, researchers have developed many tools in order to investigate pedestrians’ behavior at sidewalks. Those tools tried to study sidewalks by investigating two main components: built environment and pedestrians’ movement. This paper presents a simulation for the pedestrians’ movement at a commercial street in Cairo, using an agent-based model. The model was designed in a way by which we could examine: pedestrians’ densities, the influence of types of uses on densities, the influence of flow-generators and destinations. In addition, we categorized the uses along the selected case of study by type of service and time spent by customer. The method which we utilized for this work could be divided into two main phases: The first phase, included site video-based survey at different times and days, by which we could calculate flow rates at each generator point, and test the influence of uses on the density along the sidewalk. The second phase was to develop the model. In parallel, we focused on the uses’ types and how it affects controls pedestrians’ densities. Our results referred to a strong relation between use’s type and densities’ distribution along the street

Ethoxyquin Inhibits the Progression of Murine Ehrlich Ascites Carcinoma through the Inhibition of Autophagy and LDH

Cancer cells exhibit an increased glycolysis rate for ATP generation (the Warburg effect) to sustain an increased proliferation rate. In tumor cells, the oxidation of pyruvate in the Krebs cycle is substituted by lactate production, catalyzed by LDH. In this study, we use ethoxyquin (EQ) as a novel inhibitor to target LDH in murine Ehrlich ascites carcinoma (EAC) and as a combination therapy to improve the therapeutic efficacy of the conventional chemotherapy drug, cisplatin (CIS). We investigated the anti-tumor effect of EQ on EAC-bearing mice and checked whether EQ can sustain the anti-tumor potential of CIS and whether it influences LDH activity. Treatment with EQ had evident anti-tumor effects on EAC as revealed by the remarkable decrease in the expression of the anti-apoptotic gene Bcl-2 and by a significant increase in the expression of apoptotic genes (BAX and caspase-3). EQ also caused a significant decrease in the autophagic activity of EAC cells, as shown by a reduction in the fluorescence intensity of the autophagosome marker. Additionally, EQ restored the altered hematological and biochemical parameters and improved the disrupted hepatic tissues of EAC-bearing mice. Co-administration of EQ and CIS showed the highest anti-tumor effect against EAC. Collectively, our findings propose EQ as a novel inhibitor of LDH in cancer cells and as a combinatory drug to increase the efficacy of cisplatin. Further studies are required to validate this therapeutic strategy in different cancer models and preclinical trials

Međudjelovanje četiri-razinskog atoma u impulsnom svojstvenom stanju s jednomodnim poljem

We study the interaction between a four-level atom (ladder type) in a momentum eigenstate with a single mode cavity field in the presence of non-linearities of both the field and the intensity-dependent coupling. The constants of motion and the wave function for the atomic system have been obtained. Special attention is given to discuss some statistical aspects of the considered atomic system such as momentum increment, momentum diffusion and high-order squeezing. The influence of the Kerr-like medium and the intensity dependent coupling on the momentum increment and the high-order squeezing are investigated numerically. It is found that addition of these parameters has an important effect on both the momentum increment and the squeezing phenomenon.Proučavamo međudjelovanje četiri-razinskog atoma (poput ljestvi) u impulsnom svojstvenom stanju s jednomodnim poljem u rezonatoru, uz nelinearnosti polja i vezanja ovisnog o intenzitetu. Izveli smo stalnice gibanja valne funkcije atomskog sustava. Posebnu smo pažnju posvetili raspravi o statističkim odlikama razmatranog atomskog sustava, kao što su povećanje i difuzija impulsa i zbijanje višeg reda. Numerički smo istražili utjecaj Kerrovog sredstva i vezanja ovisnog o intenzitetu na povećanje impulsa i zbijanje višeg reda. Našli smo da dodavanje tih parametara ima snažan učinak na povećanje impulsa i pojavu zbijanja

Međudjelovanje četiri-razinskog atoma u impulsnom svojstvenom stanju s jednomodnim poljem

We study the interaction between a four-level atom (ladder type) in a momentum eigenstate with a single mode cavity field in the presence of non-linearities of both the field and the intensity-dependent coupling. The constants of motion and the wave function for the atomic system have been obtained. Special attention is given to discuss some statistical aspects of the considered atomic system such as momentum increment, momentum diffusion and high-order squeezing. The influence of the Kerr-like medium and the intensity dependent coupling on the momentum increment and the high-order squeezing are investigated numerically. It is found that addition of these parameters has an important effect on both the momentum increment and the squeezing phenomenon.Proučavamo međudjelovanje četiri-razinskog atoma (poput ljestvi) u impulsnom svojstvenom stanju s jednomodnim poljem u rezonatoru, uz nelinearnosti polja i vezanja ovisnog o intenzitetu. Izveli smo stalnice gibanja valne funkcije atomskog sustava. Posebnu smo pažnju posvetili raspravi o statističkim odlikama razmatranog atomskog sustava, kao što su povećanje i difuzija impulsa i zbijanje višeg reda. Numerički smo istražili utjecaj Kerrovog sredstva i vezanja ovisnog o intenzitetu na povećanje impulsa i zbijanje višeg reda. Našli smo da dodavanje tih parametara ima snažan učinak na povećanje impulsa i pojavu zbijanja

Morphology and anatomical structure of the larval salt gland of Artemia tunisiana under different salinities

Brine shrimps of the genus Artemia is characterized by its high adaptability to adverse environmental conditions. To elucidate the effect of salinity on the neck organ (salt gland) of Artemia tunisiana nauplii, the morphology and fine structure of the ion transporting epithelium were examined following culturing under different salinities (25, 40, 70, 140 and 180 g/L). The expression of APH-1 mRNA, using semiquantitative reverse transcription-polymerase chain reaction (RT-PCR), was also determined. The morphology and anatomical structure of the salt gland varied according to the salinity degree. At low salinities, salt gland was small, thin and flat having many shallow canals, while at high salinities, it was more elongated with deeper canals and grooves. Ultrastructure examination showed low amplification of the plasma membrane at 25 g/L with no tubular tufts, while at 40 and 70 g/L salinities, the apical and central zones showed a large amplification of the surface area of the plasma membrane. At 140 g/L salinity, the epithelial cells were more elongated and the cuticle appeared to be composed of many layers. The general structure of the salt gland of nauplii cultured at 180 g/L disappeared. Semiquantitative APH-1 mRNA analysis indicated that the gene was expressed in all tested salinities. The expression did not change remarkably between 25 and 40 g/L salinities. As salinity increased, the gene was up regulated at 70 g/L and reached the highest level at 140 g/L, while the expression level reduced significantly at 180 g/L. This coincides with the histological results and highlights the possible role of APH-1 in salinity protection in Artemia.Keywords: Artemia, nauplii, salt gland, salinity, APH-1 gene expressionAfrican Journal of Biotechnology Vol. 12(41), pp. 6032-604

Sinteza i antimikrobno djelovanje fuzioniranih heterocikličkih pirola

Pyrrole derivatives 1a,b were used as precursors for the preparation of pyrrolo[2,3-d]pyrimidine derivatives 2a,b-7a,b. Also, the formation and structure of different pyrrolotriazolopyrimidine derivatives 8a,b-11a,b were discussed. Some of the prepared products showed potent antimicrobial activity.Pirolni derivati 1a,b upotrebljeni su kao prekursori za pripravu derivata pirolo2,3-dpirimidina 2a,b7a,b. Diskutirano je i nastajanje i struktura različitih derivata pirolotriazolopirimidina 8a,b11a,b. Neki od sintetiziranih spojeva posjeduju izraženo antimikrobno djelovanje

BACTERIAL PATHOGENS OF NOSOCOMIAL INFECTIONS IN ICUS AND THEIR ANTIBIOTICS RESISTANT PATTERN AT KING KHALID HOSPITAL IN AL-KHARJ/SAUDI ARABIA

Background:The intensive care unit [ICU] is considered as infection epicenter because vulnerable population of critically ill patients and use of different invasive devices. Consequently, the ICU population has one of the highest occurrence rates of nosocomial infections leading to an enormous impact on morbidity, hospital costs, and often survival. In addition, the increasing problem of antibiotic resistance loads the burden of nosocomial infection in the ICU. Constant and careful global monitoring for multidrug-resistant bacteria is needed to minimise the possibility of appearance and dissemination of new resistant isolates and to avoid complications in treatment choices. Methods:This study was carried out from March to June 2016 in King Khalid Hospital [Al-Kharj-KSA] to explore the multidrug-resistant bacteria, Extended Spectrum - lactamase bacteria [ESBLs] and the possibility of carbapenems resistant bacteria isolated from clinical samples of patients in the ICUs. A total of 317 different clinical samples were received for cultivation and antibiogram during the study period. Samples were cultivated on Blood agar, MacConkey agar, CLED, EMB agar and Mannitol salt agar. Gram stain, colony morphology and biochemical tests were done.The final identification results of the causative agents and its sensitivity profile were obtained by automated procedures "Phoenix 100/BD company". Minimum inhibitory concentration [MIC] results were interpreted according to Clinical and laboratory standard institute [CLSI] guidelines. Results:Out of 317 total samples processed during the study, significant growth was shown in 62 samples [19.5%]. Respiratory samples showed the highest rate of positive growth [40.3% out of 62] followed by urine [20.96% out of 62]. Fifty-seven isolates [91.94 %] were gram-negative and five isolates [8.06%] were gram-positive. K. pneumoniae was the most frequently isolated among Gram-negative with16 isolates [28%] followed by P. aeruginosa 12 [21%]. All isolates of P. aeruginosa, Acinetobacter spp., Providencia spp., Enterobacter spp., Citrobacter spp., Serratia spp. were MDR [100%] while five isolates [71.4%] of Proteus mirabilis, and 11 [69%] of K. pneumoniae were MDR. ESBLs were confirmed in 39 [83%] isolates out of 47 MDR gram-negatives; among them, 11[28.2%] were K. pneumoniae and10 [25.64%] isolates of P. aeruginosa. Resistance to carbapenems was detected in 23 [48.94%] isolates of MDR gram-negative bacteria; among them, 10 [43.48%] isolates of P. aeruginosa, and 6[26.1%] isolates each of Acinetobacter spp. and K. pneumoniae. Conclusion:Considerable efforts and regular evaluation of ESBL and carbapenems resistant bacteria are of great importance both in hospital and community to avoid the appearance of new bacterial isolates which may resist all clinically used antibiotics. Keywords: Nosocomial infection, MDR, ESBL, Carbapenems, Resistance, Bacteria