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Abstract This paper investigates experimentally and numerically structural performance of reinforced concrete (RC) circular column under double curvature buckling moment. RC circular columns are popularity embraced in RC structures not only owing to its esthetic, attractive appearance and easy for construction, but also for its better contribution for stress resistance. However, the corner or edge columns may be exposed to edge moment (EM) transferred from beam–column joint with double curvature effect. The current investigation proposes to understand the structural exhibition of such columns subjected to double curvature buckling edge moment generated at beam–column joint considering some parameters. A total number of 11 full-scale RC circular columns were constructed, installed, and then tested up to failure studying four parameters. These parameters were: clear height-to-diameter ratio (λ), longitudinal and lateral steel ratios (μ and ρ, respectively) and concrete type. The λ ratio has been introduced with: 4.89, 4.51 and 4.14. The μ ratio has been presented by: 2.2%, 2.3%, 2.6%, and 3.1%, while the ρ ratio was employed with: 0.84%, 0.93%, 1.00% and 1.18%. Three concrete types were studied; one of them was normal concrete (NC), while the other ones were high-performance concretes (HPCs) which were engineered cementitious composite (ECC) and high-strength fiber reinforced concrete (HSFRC). Experimental outcomes revealed that all studied parameters could affect and upgrade the structural performance; however, both longitudinal reinforcement and height-to-diameter ratio provided significant enhancement (about 51%–64%). Parallel to those exploited experimentally, nonlinear three-dimensional finite element models (FEMs) were installed, executed and established considering experimental outcomes producing an acceptable model with an under/over-estimation of about 4%.

In recent decades, reinforced concrete (RC) shear walls have been one of the best structural solutions to resist lateral load in high-rise buildings. Shear wall openings are essential for preparations and architectural requirements, which weaken the wall, reducing bearing capacity, energy absorption, and stiffness while also causing stress concentrations. This paper presents a comprehensive finite element (FE) investigation of the behavior and performance of RC shear walls with openings and subjected to lateral loads. The study aims to evaluate the influence of various parameters, such as opening location, size, wall aspect ratio, axial load, and concrete strength, which affect the performance of shear walls. FE models were developed to simulate the seismic response of RC shear walls under the combined effect of constant axial and lateral loads. The obtained results from the FE model showed a successful validation using the experimental data available in the literature. The FE analysis results demonstrate that the inclusion of lower openings leads to a 25% decrease in the bearing capacity of the wall when compared to the upper openings. Moreover, it was observed that augmenting the sizes of the openings and the aspect ratios of the wall resulted in declines in the strength, stiffness, and energy absorption capacity of the wall while simultaneously enhancing the ductility and displacement of the RC shear walls.

Abstract Background More than a century has passed since it was discovered that many bacteria produce indole, but research into the actual biological roles of this molecule is just now beginning. The influence of indole on bacterial virulence was extensively investigated in indole-producing bacteria like Escherichia coli. To gain a deeper comprehension of its functional role, this study investigated how indole at concentrations of 0.5-1.0 mM found in the supernatant of Escherichia coli stationary phase culture was able to alter the virulence of non-indole-producing bacteria, such as Pseudomonas aeruginosa, Proteus mirabilis, and Klebsiella pneumoniae, which are naturally exposed to indole in mixed infections with Escherichia coli. Results Biofilm formation, antimicrobial susceptibility, and efflux pump activity were the three phenotypic tests that were assessed. Indole was found to influence antibiotic susceptibly of Pseudomonas aeruginosa, Proteus mirabilis and Klebsiella pneumoniae to ciprofloxacin, imipenem, ceftriaxone, ceftazidime, and amikacin through significant reduction in MIC with fold change ranged from 4 to 16. Biofilm production was partially abrogated in both 32/45 Pseudomonas aeruginosa and all eight Proteus mirabilis, while induced biofilm production was observed in 30/40 Klebsiella pneumoniae. Moreover, acrAB and oqxAB, which encode four genes responsible for resistance-nodulation-division multidrug efflux pumps in five isolates of Klebsiella pneumoniae were investigated genotypically using quantitative real-time (qRT)-PCR. This revealed that all four genes exhibited reduced expression indicated by 2^−ΔΔCT

Salmonella enterica is a common foodborne pathogen that causes intestinal illness varying from mild gastroenteritis to life-threatening systemic infections. The frequency of outbreaks due to multidrug-resistant Salmonella has been increased in the past few years with increasing numbers of annual deaths. Therefore, new strategies to control the spread of antimicrobial resistance are required. In this work, we found that N-acetyl cysteine (NAC) inhibits S. enterica at MIC of 3 mg ml-1 and synergistically activates the bactericidal activities of common antibiotics from three-fold for ampicillin and apramycin up to1000-fold for gentamycin. In addition, NAC inhibits the expression of virulence genes at sub-inhibitory concentrations in a dose-dependent manner. The whole-genome sequencing revealed that continuous exposure of S. enterica to NAC leads to the development of resistance; these resistant strains are attenuated for virulence. These results suggest that NAC may be a promising adjuvant to antibiotics for treating S. enterica in combination with other antibiotics.

This paper presents an experimental investigation of the shear improvement of defected reinforced concrete (RC) beams using sustainable aluminum boxes filled with high performance concretes (HPCs). The study compares the performance of eleven RC beams with different configurations of aluminum boxes, filling materials, and inclination angles. Additionally, it examines the effect of reinforcing the ultra-high-performance concrete (UHPC) used to fill these boxes with glass fiber reinforced polymer (GFRP) bars. The results show that the proposed technique can effectively restore and enhance the load-deflection behavior, ultimate capacity, stiffness, and energy absorption of the beams. Inclining aluminum boxes within beams at a 45-degree angle and filling them with strain-hardening cementitious composites (SHCCs) partially restores performance. A beam with three boxes showed significant improvements over the defected beam, achieving 65 % higher stiffness, 44 % higher cracking load, and 33 % higher ultimate load. The optimal configuration was found to be 60-degree inclined aluminum boxes filled with UHPC and embedded GFRP bars. This configuration achieved a near-identical performance to the non-defected control beam and surpassed it in some respects. Furthermore, a two-pronged approach was employed. Firstly, finite element models (FEMs) were developed and carefully validated against experimental results. These validated models then became the foundation for a parametric study, allowing researchers to investigate the influence of various parameters on the beam's performance. The parametric study indicates that with a fixed thickness of the aluminum boxes used, beams strengthened with boxes filled with UHPC have higher shear capacity compared to those strengthened with boxes filled with SHCC. Secondly, a theoretical formula was proposed to predict the total shear capacity of the strengthened beams. This formula exhibited excellent agreement with both the experimental data and the finite element (FE) results, solidifying its potential as a practical tool for engineers in design and analysis.

Structural systems often undergo changes due to variations in the usage, the loading conditions, or the presence of defects in their elements. The problem can be exacerbated when there is insufficient overlap between reinforcing bars in critical moment zones. This article investigates the behavior of reinforced concrete cantilever beams exhibiting insufficient overlap between bars that used as main reinforcing steel bars in the negative moment zone. Various strengthening techniques were employed in order to improve these defected cantilever beams. Eleven beams underwent flexural testing until reaching failure. The experimental parameters encompassed the strengthening scenarios and the bonded length. Three strategies were used: the application of stainless-steel plates (SSPs) as externally bonded reinforcement, near surface mounted (NSM) reinforcement in which additional deformed steel bars were bonded utilizing engineering cementitious composites, and externally pre-stressing technique. The anchorage length was examined at 40, 50, and 60 times the internal bar diameter. It was noted that the most substantial improvement achieved with the NSM method, followed by the externally pre-stressing method. It is worth mentioning that most of the beams failed in a flexural manner, with partial debonding occurring in beams strengthened using external strengthening. Moreover, this article includes the development of a numerical model employing the finite element method to replicate the response observed from the experimentally tested beams. The accuracy of the model was confirmed through the comparison of its outcomes with the experimental data, demonstrating an acceptable level of accuracy with deviations of less than 4.4 %. This successful numerical investigation was also used to conduct a parametric study. From this study it is evident that the effect of debonding on SSPs can be reduced by adding steel anchors at the ends of these plates. Finally, an analytical method was proposed to calculate the ultimate load capacity of strengthened reinforced concrete beams.

Abstract Background Antimicrobial resistance is a global concern, linking bacterial genotype and phenotype. However, variability in antibiotic susceptibility within bacterial populations can lead to misclassification. Heteroresistance exemplifies this, where isolates have subpopulations less susceptible than the main population. This study explores heteroresistance in Gram-negative bacteria, distinguishing between carbapenem-sensitive isolates and stable heteroresistant isolates (SHIs). Methods A total of 151 Gram-negative clinical isolates including Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii and Proteus mirabilis from various sources were included. Heteroresistant isolates and their stability were detected by disc-diffusion technique while genotypic analysis was carried out by PCR and efflux activity was assessed by ethidium bromide (EtBr)-agar cartwheel method. Results A total of 51 heteroresistant subpopulations were detected, producing 16 SHIs upon stability-detection. Amplified resistance genes and EtBr-agar cartwheel method showed a significant difference between resistant subpopulations and their corresponding-sensitive main populations. Conclusion Genotypic analysis confirmed that genetic mutation can lead to resistance development although the main populations were sensitive, thereby leading to treatment failure. This is a neglected issue which should be highly considered for better treatment outcomes.

This study investigates the effectiveness of different dowel bar techniques in enhancing the performance of joints connecting concrete slabs in jointed plain concrete pavement. Eighteen specimens were divided into three groups to explore the influence of various factors including dowel embedment length (100 mm, 150 mm, and 200 mm) on joint behavior, dowel anchors provided to the ends of the dowels, and the effect of incorporating strain-hardening cementitious composites in the middle slab on joint performance. Results revealed that increasing dowel length improved load transfer efficiency and resulted in more favorable crack patterns, while end anchors further enhanced crack distribution by preventing debonding between the dowel and concrete. Longer dowels increased ultimate load capacity by 38 %. This increase was 30 %, and 10 %, for specimens with end anchors and strain-hardening cementitious composites, respectively. Both longer dowels and strain-hardening cementitious composites significantly enhanced energy absorption capacity. Finally, a finite element model developed to simulate the behavior of the tested specimens showed good agreement with the experimental data. Based on the finite element results, increasing the base layer thickness, using advanced concrete materials like strain-hardening cementitious composites, or incorporating anchors can significantly enhance the structural performance of jointed plain concrete pavement.

Abstract Objective Carbapenemase production and biofilm formation in K. pneumoniae are crucial factors influencing the pathogenicity and antibiotic resistance of this bacterium. This study investigated the interplay between carbapenemase production and biofilm formation in K. pneumoniae clinical isolates. Results The distribution of biofilm-forming ability significantly differed between carbapenemase-producing (CP-Kp) (n = 52) isolates and carbapenemase-nonproducing (CN-Kp) isolates (n = 37), suggesting a potential link between carbapenemase production and biofilm formation. All the bla NDM-1-harbouring isolates demonstrated biofilm formation, with varying levels classified as strong (33.33%), moderate (22.22%), or weak (44.45%). bla NDM-1 and bla KPC-coharbouring isolates did not exhibit strong or moderate biofilm formation. bla NDM-1 and bla OXA-48-coharbouring isolates were predominantly moderate (48.65%), followed by weak (32.43%), with none showing strong biofilm production. These findings suggest a correlation between the presence of carbapenemases and biofilm-forming ability; however, the heterogeneity in biofilm-forming abilities associated with different carbapenemase types and the absence of strong biofilm producers in the detected carbapenemase combinations prompt a closer look at the complex regulatory mechanisms governing biofilm formation in CP-Kp isolates.

The study explores the feasibility of a new all-steel buckling restrained brace (BRB) with the double pre-tensioning system as an alternative to conventional concentrically braced frames by using finite element method (ABAQUS program), And to verify modeling, use U-V1 specimen results and compare them with test results. The restraining element in an all-steel BRB is built from a rectangular plate with a double cross arm and cables, making it easy to fabricate, inspect, and replace after a severe earthquake. Numerical analyses were conducted on four groups: first group of specimens using dynamic loading to achieve the minimum thickness for stable hysteretic behavior and high efficiency for BRB, and three groups of specimens using monotonic loading to achieve the best pre-tensioning forces value in steel 37, 44 and 52 for greater efficient use of all steel BRB. The results showed a 66% improvement in bearing capacity, with the external restraining case thickness reduced to 20 mm, making it lightweight, economical, and easy to maintain. The specimens with a pre-tensioning force of 70 kN, 50 kN and 40 kN providing a 31%, 51% and 73.2 % for steel 37, 44 and 52 respectively over than the design specimen without pre-tensioning system.

This paper investigates, experimentally and numerically, the shear strengthening of Normal Concrete (NC) beams using post-tensioning steel bars and Engineered Cementitious Composite (ECC) reinforced with chemically cured Palm Fronds (PFs). The benefits of strain-hardening ECC and the tensile strength of PFs cured with 6% wt Alkali NaOH solution beside post-tensioned bars have been employed herein. Seven full-scale Reinforced Concrete (RC) beams were fabricated and experimented with under three-point loading until failure. The test parameters include the strengthening technique, type, and configuration of the material used for strengthening. The strengthening process has been implemented through two techniques: Externally Bonded Reinforcement (EBR) and Near-Surface Mounted (NSM) Reinforcement. The strengthening materials have been configured and placed in horizontal, vertical, and inclined positions. The effectiveness of the strengthening methods has been evaluated by examining their cracking propagations, load-deflection responses, collapse modes, elastic stiffness, and absorbed energy. It was found that the proposed strengthening systems could significantly control the crack pattern and failure mode, and they could enhance the ultimate load amplitude up to 37% and 50% for NSM ECC with PFs and EBR post-tensioning steel bars, respectively. Nonlinear three-dimensional finite element models of the tested beams were developed and validated with the test data, where it was found that finite element models predict the structural performance of tested beams with a maximum error of only 2%.

Precast rectangular reinforced concrete (PRRC) beams are joined on construction sites using concrete in situ to achieve the desired length. Limited research exists on the effect of intermediate connection shapes and the types of infilled concrete on the flexural performance of PRRC beams. This paper presents a comprehensive experimental and numerical investigation into the performance of PRRC beams with various intermediate connection geometries and infilled materials under flexural loading. The study examines rectangular, triangular, and semi-circular intermediate connections, along with the performance of beams infilled with normal concrete (NC), engineered cementitious composites (ECC), ultra-high-performance ECC (UHPECC), and rubberized ECC (RECC). The experimental results indicate that the rectangular intermediate connection exhibits superior performance in terms of strength and energy absorption compared to the triangular and semi-circular shapes. Beams incorporating UHPECC demonstrated the most significant improvements in strength and energy absorption, outperforming those with ECC and RECC for any shape of intermediate connection. Moreover, beams with rectangular connections and UHPECC infill exhibited the most significant increase in energy absorption and ultimate load compared to the beams with ECC and RECC. The ultimate load of the beams with UHPECC and tensile reinforcement bar diameters of 10 mm and 12 mm increased by 13% and 29%, respectively, compared to the control beam. The energy absorption of the beams with tensile reinforcement bar diameters of 10 and 12 mm was found to be 75% and 184% higher, respectively, than the control beam. In addition, an increase in tensile bar diameter was found to enhance both the energy absorption and the ultimate load capacity of the beams, regardless of the type of infill concrete. Beams incorporating UHPECC demonstrated the most significant improvements in strength and energy absorption, outperforming those with ECC and RECC. In particular, beams with rectangular connections and UHPECC infill exhibited an increase in energy absorption and ultimate load of up to 184% and 29%, respectively. UHPC was calculated to be as high as 184%, and 29%, respectively, compared to the control beams. In addition, an increase in tensile bar diameter was found to enhance both energy absorption and ultimate load capacity. Finite element modeling (FEM) was developed and validated against the experimental results to ensure accuracy. A parametric study was conducted to study the effects of various concrete types in triangular and semi-circular connections, as well as the influence of intermediate connection length on semi-circular connections under flexural loads. The findings reveal that increasing the length of intermediate connections increases the ultimate load of the beams.

Edible coats derived from a natural animal source and conveying natural active compounds to meat products may be the golden solution that sums up various preserving benefits. In this study, the main goal was to ascertain whether casein coat and casein coat enhanced with 1000 ppm Sorbic acid and 600 ppm ascorbic acid may be utilized to increase the acceptability of frozen beef kofta. In addition to the control trial, two coats were compared: a plain casein coat and a casein coat enhanced with 1000 ppm Sorbic acid and 600 ppm ascorbic acid. Organoleptic, bacteriological, proximate chemical analysis, pH, thiobarbituric acid reactive substances ("TBARS"), cooking characteristics, and instrumental colour evaluations were examined for each kofta treatment during three months of storage at -18°C. Results revealed that casein coats were able to boost several sensory attributes of raw and cooked kofta in addition to the overall acceptability of the raw product. Moreover, coats significantly decreased all tested bacterial counts and thiobarbituric acid reactive substance (TBARS) values in addition to maintaining compositional parameters from deteriorating during the storage period. As for cooking characteristics, they were all improved by applying casein coats when compared to the control. Casein coated with acid surpassed the plain casein coats in improving all parameters in addition to having the best colour scores for all three months of storage. It has been concluded that casein coats can be utilized to improve the quality of beef kofta without colour or flavour problems.

The paper presents a novel sustainable technique for shear strengthening of reinforced concrete (RC) beams utilizing embedded aluminum boxes and prestressed high-performance concretes (HPCs). It addresses the challenges faced by existing RC structures, such as environmental threats, increased loading, and aging, which often lead to shear reinforcement deficiencies. Through an experimental program, the paper evaluates the impact of several parameters on the shear performance of beams, including the type of concrete filling the aluminum boxes, the type and diameter of reinforcement, and the level of prestressing force. The findings demonstrate the potential of this innovative technique to enhance the shear behavior of damaged RC beams, contributing to more sustainable construction practices. Results revealed that increasing the bar diameter provided marginal additional benefits. Moreover, the use of glass fiber reinforced polymer (GFRP) bars offered superior strengthening compared to steel bars. Additionally, beams strengthened with ultra-high-performance concrete (UHPC)-filled aluminum boxes and embedded steel/GFRP bars, demonstrated improved performance compared to strain-hardening cementitious composites (SHCC)-filled aluminum boxes. Applying a prestressing force significantly enhanced the behavior of strengthened beams, the ultimate capacity of one of them reaching that of the control beam. The level of enhancement directly correlated with the applied prestressing force. This research successfully validated a new finite element model (FEM) for analyzing concrete beams strengthened with aluminum boxes. The model accurately predicted shear strength of these beams. Additionally, a proposed formula for calculating shear capacity closely matched experimental results, showing a maximum discrepancy of only 2.5 %.

Abstract Background Hydrocephalus or ventriculomegaly is a condition brought on by an overabundance of cerebrospinal fluid (CSF) in the ventricular system. The major contributor to posttraumatic hydrocephalus (PTH) is traumatic brain injuries (TBIs), especially in individuals with occupations set in industrial settings. A variety of criteria have been employed for the diagnosis of PTH, including the combination of neurological symptoms like nerve deficits and headache, as well as an initial improvement followed by a worsened relapse of altered consciousness and neurological deterioration, which is detected by computed tomography‐brain imaging that reveals gradual ventriculomegaly. Aim In this article, we discuss and summarize briefly the current understandings and advancements in the management of PTH. Methods The available literature for this review was searched on various bibliographic databases using an individually verified, prespecified approach. The level of evidence of the included studies was considered as per the Centre for Evidence‐Based Medicine recommendations. Results The commonly practiced current treatment modality involves shunting CSF but is often associated with complications and recurrence. The lack of a definitive management strategy for PTH warrants the utilization of novel and innovative modalities such as stem cell transplantations and antioxidative stress therapies. Conclusion One of the worst complications of a TBI is PTH, which has a high morbidity and mortality rate. Even though there hasn't been a successful method in stopping PTH from happening, hemorrhage‐derived blood, and its metabolic by‐products, like iron, hemoglobin, free radicals, thrombin, and red blood cells, may be potential targets for PTH hindrance and management. Also, using stem cell transplantations in animal models and antioxidative stress therapies in future studies can lower PTH occurrence and improve its outcome. Moreover, the integration of clinical trials and theoretical knowledge should be encouraged in future research projects to establish effective and updated management guidelines for PTH.

Numerous existing reinforced concrete (RC) buildings don’t fulfill current seismic code provisions as they haven’t been designed to satisfy these provisions. Also, due to many environmental factors, structural members such as columns, beams, and slabs are exposed to severe deterioration leading to high-risk levels. In this research, the performance of an existing seven-floor reinforced concrete building in Zagazig city, Egypt, constructed about 50 years ago, without considering the seismic requirements prescribed in the current Egyptian code (ECP-2012) is studied. The studied building suffers severe deterioration in its main structural elements, especially the basement floor slab. SAP2000 software is utilized to evaluate the structural behavior of the building under vertical loads (dead and live loads). The model failed to fulfill the ECP-2012 requirements under the applied loads. After building investigation, a retrofitting technique was proposed through providing the building with new grid beams at the basement floor level as well as replacing the existing basement floor slab with a new one. Moreover, RC jackets were provided to all basement floor columns. Through response spectrum analysis (RSA), the performance of the building with the newly proposed technique was assessed considering a peak ground acceleration equals 0.15 g (seismic zone 3). The model showed a significant enhancement in its response that fulfilled the ECP requirements concerning both strength and serviceability. Utilizing SeismoStruct software, the horizontal capacity of the model was inspected through the pushover analysis to check the efficiency of the proposed retrofitting technique. The model showed acceptable capacity in its two main directions.

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This study evaluates the performance of Reinforced Concrete (RC) beams enhanced in shear using Engineered Cementitious Composites (ECCs) and Carbon Fiber-Reinforced Polymers (CFRPs). The experimental study encompasses fifteen RC beams. This set includes one control specimen and fourteen beams fortified in shear with Externally Bonded (EB) composites. Two of these specimens were enhanced with ECC layers, while the remaining were augmented with combined CFRP-ECC layers. Variables in the test included the ECC layer thickness, matrix type, number of CFRP layers, and strengthening configurations such as full wrapping, vertical strips, and inclined strips. The results indicated that the shear capacity of the fortified beams increased by 61.1% to 160.1% compared to the control specimen. The most effective structural performance was observed in the full wrapping method, which utilized a single CFRP layer combined with either 20 mm or 40 mm ECC thickness, outperforming other techniques. However, the inclined strip method demonstrated a notably higher load-bearing capacity than the full wrapping approach for beams with double CFRP layers paired with 20 mm and 40 mm ECC thicknesses. This configuration also exhibited superior ductility compared to the rest. Furthermore, the experimental shear capacities obtained were juxtaposed with theoretical values from prevailing design standards.

Reinforced concrete (RC) columns cannot get supreme confinement by using the customary steel stirrups reinforcement because of the requirements for the spacing distances between the stirrups in addition to concrete continuance problem. For this, Steel Mesh (SM) externally wrapped around the outer perimeter of the column as contributory confinement is being widely used due to its features. Limited tests focused on using SM for the internal confinement around the reinforcing cage of RC columns. Moreover, no experimental comparison was presented between RC columns internally and externally confined using SM. This paper investigates experimentally the behavior of circular RC columns confined internally or externally by SM. Six short RC columns have been subjected to axial loading until failure. The main studied parameters were SM schemes, number of SM wraps, SM position (internally or externally), and the steel stirrups existence. Results demonstrated that SM could decrease the crack opening, diminish the concrete spalling, increase the maximum failure load, and enhance the ductility, energy absorption, and column stiffness. Furthermore, the partial internal confinement using two wraps of SM around the steel ties presented the maximum capacity with reasonable ductility. In general, internally confined columns showed better behavior than the externally confined one

This paper investigates numerically the behavior of Reinforced Concrete (RC) beams, strengthened using Carbon Fiber Reinforced Polymers (CFRP) sheets, subjected to impact loading. Three-dimensional finite element analysis was performed and its results were verified against experimental ones available in the literature showing good agreement. Then, a comprehensive parametric study was performed to investigate the effect of studied parameters on the strengthened RC beams. The main studied parameters were the type and size of reinforcing bars, geometric characteristics of externally bonded CFRP sheets (width, length, and thickness), impact velocity, and the position of the impactor with respect to the beam. Results showed that the use of externally bonded CFRP sheets enhanced the beam capacity and failure mode, and reduced the mid-span deflection. On the other hand, increasing the impact velocity increased the mid-span displacement, however, the use of � CFRP bars as internal reinforcement could reduce the increase in the deflection. Moreover, changing the position of the impact load application showed a significant effect on the mid-span displacement as well as the failure mode of tested beams

Abstract Background Salmonella enterica serovar Typhimurium is an intestinal pathogen capable of infecting a wide range of animals. It initiates infection by invading intestinal epithelial cells using a type III secretion system encoded within Salmonella pathogenicity island 1 (SPI-1). The SPI-1 genes are regulated by multiple interacting transcription factors. The master regulator is HilD. HilE represses SPI-1 gene expression by binding HilD and preventing it from activating its target promoters. Previous work found that acetate and nutrients synergistically induce SPI-1 gene expression. In the present study, we investigated the role of HilE, nominally a repressor of SPI-1 gene expression, in mediating this response to acetate and nutrients. Results HilE is necessary for activation of SPI-1 gene expression by acetate and nutrients. In mutants lacking hilE, acetate and nutrients no longer increase SPI-1 gene expression but rather repress it. This puzzling response is not due to the BarA/SirA two component system, which governs the response to acetate. To identify the mechanism, we profiled gene expression using RNAseq in the wild type and a ΔhilE mutant under different growth conditions. Analysis of these data suggested that the Rcs system, which regulates gene expression in response to envelope stress, is involved. Consistent with this hypothesis, acetate and nutrients were able to induce SPI-1 gene expression in mutants lacking hilE and the Rcs system. Conclusions While the exact mechanism is unknown, these results demonstrate the HilE, nominally a repressor of SPI-1 gene expression, can also function as an activator under the growth conditions investigated. Collectively, these results provide new insights regarding SPI-1 gene regulation and demonstrate that HilE is more complex than initially envisioned.

Abstract Background The surgery of giant intracranial meningiomas (GIM) is difficult due to its large size, prominent vascularity, including and limiting visualization of various neurovascular structures, and severe cerebral edema. In this study, we will evaluate the surgical outcome of giant meningiomas according to our experience at our hospital in management of giant intracranial meningioma. Main body A retrospective analysis of 48 patients with histologically proven meningioma (≥ 6-cm diameter) who underwent surgical treatment at Benha University hospitals over a period of 5 years (June 2014/June 2019) is presented. Details regarding clinical presentation, imaging findings, surgical results and complications, and follow-up status were collected. The study group was composed of 41 females and 7 males. The age of the study group ranged from 38 to 69 years with an average of 49 years. The mean follow-up period was 36 months. Different approaches were used according to tumor location with the aim of gross total removal. Gross total removal was achieved in 90% of cases (43 cases). There were 2 cases with intraoperative complications not related to surgery. Recurrence was present in 4 cases. Mortality in this series was 4% (2 cases) with no reported intraoperative mortality. Conclusion Management of giant intracranial meningioma is a relatively common practice in neurosurgical centers in developing countries with the aim of radical total surgical removal being the first and most optimum option. Large size makes surgery difficult, but young age, meticulous surgical techniques, proper localization, trying to minimize operative time, and Simpson grade are of special value. Interdisciplinary cooperation is essential to avoid the common complications like pulmonary embolism (PE), postoperative hematoma in tumor bed that leads to bad surgical outcome.

Abstract Background Posterior fossa brain tumours are one of the most devastating forms of human illnesses which are more common in children. Brainstem compression, herniation and death are the risks with tumours in this critical location. Objective To evaluate our results, complications and outcome of posterior fossa tumour surgery in Benha University Hospital. Patients and methods A prospective study including 44 patients with posterior fossa tumours were performed at the Neurosurgery Department in Benha University Hospital between the period of March 2015 and October 2018. In each case, diagnosis was made clinically and confirmed radiologically and histo-pathologically. Results Out of 44 patients, 28 (63.6%) patients were males and 16 (36.4%) were females. The mean age was 17.5 + 14.2 years (ranged 2–30 years). This study showed that excellent surgical outcome was observed in 12 cases (27.3%), good in 22 cases (50%) while poor outcome was observed in 10 cases (22.7%). The best outcome is astrocytoma then ependymoma while the worst outcome is metastatic then medulloblastoma which is statistically insignificant. Conclusion The surgical treatment of posterior fossa tumours still represents a challenge for neurosurgeons. Our Benha experience shows the accepted results, complications and surgical outcome in relation to previous clinical studies. Trial registration IRB#3747. Registered 18 September 2018.

Background: Vitamin D is a group of fat-soluble corticosteroid responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and multiple other biological effects. In humans, the most important compounds in this group are vitamin D3 [also known as cholecalciferol] and vitamin D2 [ergocalciferol].Aim of the work: The aim of this thesis is to assess Vitamin D3 [VD3] level in patients with sino-nasal polypi in comparison with normal individuals.Patients and Methods: This prospective comparative [case-control] study conducted by the Department of ENT, Al-Azhar University Hospitals in the period from March 2019 to September 2019 and included 40 individuals who were selected by inclusion and exclusion criteria, both genders, all patients had been counseled about the nature of the study and informed written consent has been obtained.Results: Serum level of VD3 in patients with chronic rhinosinusitis with sinonasal polyps [CRSwNP] and allergic fungal rhinosinusitis [AFRS] was significantly lower than that of control subjects. Vitamin D levels ranged from 8.74 to 39 ng/ml, and there was statistically significant decrease of serum vitamin D levels in patient group when compared to control group [16.20±4.29 vs 30.56±4.83 respectively]. In addition, there was significant increase of patients with deficient and insufficient vitamin D levels in patient group when compared to control group.Conclusion: VD3 may constitute an inexpensive prophylactic and cost effective option in the therapeutic armamentarium in reducing inflammation either by itself or as a synergistic agent to traditional agents in patients suffering from sino-nasal polypi.

Abstract Background Salmonella enterica serovar Typhimurium is a common food-borne pathogen. S. enterica uses a type III secretion system encoded within Salmonella pathogenicity island 1 (SPI-1) to invade intestinal epithelial cells. A complex network of interacting transcription factors regulates SPI-1 gene expression. In addition, SPI-1 gene expression is coupled to flagellar gene expression. Both SPI-1 and flagellar gene expression are bistable, with co-existing populations of cells expressing and not expressing these genes. Previous work demonstrated that nutrients could be used to tune the fraction of cells expressing the flagellar genes. In the present study, we tested whether nutrients could also tune the fraction of cells expressing the SPI-1 genes through transcriptional crosstalk with the flagellar genes. Results Nutrients alone were not found to induce SPI-1 gene expression. However, when the cells were also grown in the presence of acetate, the concentration of nutrients in the growth medium was able to tune the fraction of cells expressing the SPI-1 genes. During growth in nutrient-poor medium, acetate alone was unable to induce SPI-1 gene expression. These results demonstrate that acetate and nutrients synergistically activate SPI-1 gene expression. The response to acetate was governed by the BarA/SirA two-component system and the response to nutrients was governed by transcriptional crosstalk with the flagella system, specifically through the action of the flagellar regulator FliZ. Conclusions Acetate and nutrients are capable of synergistically activating SPI-1 gene expression. In addition, these signals were found to tune the fraction of cells expressing the SPI-1 genes. The governing mechanism involves transcriptional crosstalk with the flagellar gene network. Collectively, these results further our understanding of SPI-1 gene regulation and provide the basis for future studies investigating this complex regulatory mechanism.

Background and Aims: Human schistosomiasisis one of the most important and unfortunately neglected tropical diseases. The aim of the current study was to investigate the prevalence and characterize colonic schistosomiasis, among symptomatizing rural inhabitants of the Middle Northern region of the Egyptian Nile delta. Patients and Methods: This study recruited 193 inhabitants of the rural community in the Egyptian Nile Delta referred for colonoscopy because of variable symptoms. After giving a written informed consent, they were exposed to thorough history; clinical examination; stool analysis; abdominal ultrasonography, and pan-colonoscopy with biopsies. Results:Twenty-four cases out of the 193 patients had confirmed active schistosomiasis with prevalence rate of 12.4%. Bleeding with stool was the predominant manifestation of active schistosomainfection among the cases either alone or in combination with abdominal pain. On clinical examination, the majority of the patients (n=17; 70.8%)did not have organomegaly and 25% of them had clinically palpable splenomegaly. As far as, 75% of them had sonographically detected hepatic peri-portal fibrosis. Also 66.6% of patients havesignificant endoscopic lesions (polyps, ulcers, mass-like lesions), and 16.6% of them had colonic affection beyond the recto-sigmoid region. Conclusion:Colonic schistosomiasis still running among symptomatizing rural inhabitants of the Egyptian Nile Delta at a rate of 12.4%. Of them66.6% had significant endoscopic colorectal lesions. This persistent transmission of schistosomiasis in the rural community of the Egyptian Nile Delta sounds the alarm for continuing governmental efforts and plans to screen the high-risk groups.

In this paper a new image compression schema that uses three-dimensional discrete cosine transform and relies on twodimensional discrete wavelet transform, for image classification, is proposed. The proposed technique utilizes a modified quantization table and a method for converting a three-dimensional image cube into a one-dimensional array, which provides better coding efficiency in the run length coding step. To ensure faster performance, this technique provides proposed parallel computation system. Several images have been used to test the proposed algorithm. Experimental results demonstrate that the proposed algorithm outperforms previous compression methods in terms of peak-signal-to-noise ratio with a lower compression bit rate.

Background Data: With advancement of MRI technology, numerous studies have showed probability of spontaneous regression of the herniated disc. This is usually associated with recovery of neurological symptoms. Purpose: The purpose of this study is to highlight the potential for spontaneous resorption of intervertebral disc herniation, review the literature and discuss the duration of conservative treatment. Study Design: Retrospective clinical case study. Patients and Methods: In this study patients with spontaneous regression of intervertebral disc herniation were reviewed. All patients were presented with a single level intervertebral disc herniation and radiculopathy. Six patients had lumber disc herniation and one patient had cervical disc hernition. Surgical intervention was offered to them but all patients refusedand were treated conservatively. Initial MRI was done at presentation and repeated in follow up. Results: Seven patients were identified with a mean age of 35.5 years (range from 28 to 47). Five patients were male and 2 were female. All patients recovered from their radicular pain within a mean of 5 weeks (Range 3-8) of conservative treatment. Repeated MRI after a mean 12 months (Rang 6-18) showed spontaneous resorption of the herniated intervertebral disc in all patients. Conclusion: Herniated intervertebral disc can be resorbed spontaneously. A chance of conservative treatment should be given to patients with radicular pain caused by intervertebral disc herniation with no neurological deficits. If patients report improvement of his symptoms, conservative therapy should be continued. If there is no improvement, surgery should be considered. The reasonable duration of conservative therapy may two months. (2016ESJ095)

Ramadan is a sacred month for Muslims all around the world. During this lunar-based month, healthy adult Muslims are obligated to abstain from eating, drinking, smoking, or using oral medications from predawn to sunset. Followers will typically eat just after sunset and again before dawn (1). The Islamic lunar Hijri calendar is 11 days shorter than the Gregorian solar calendar, and therefore, the month of Ramadan can occur in any season of the year. The hours spent on fasting can vary from 12 to 18 h, depending on the seasonal and regional features, and this ultimately will affect the ability of individuals and patients to fast. In the North Pole, the day time is very long and may reach up to 22 hours; toward the equator the temperature and humidity are high. These entire environmental factors directly decrease the ability of patients to complete one month of continuous fasting. The studies focusing the impact of fasting during Ramadan on different liver diseases are scarce (2,3) and that is why no structured guidelines for fasting and liver diseases(4) have been set up.

Amoebic liver abscess is a complication of amoebiasis that needs early diagnosis and proper treatment before further complications occur. We report a-35 year old female presented by fever and dyspnea due to huge liver abscess complicated by massive right side empyema. The patient was effectively treated by percutaneous drainage for both the right lobe abscess and empyema together with pharmaco-logic agents.

BACKGROUND: Inadequate reporting undermines findings of randomized controlled trials (RCTs). This study assessed and compared articles published in high-impact general medical and specialized journals. METHODS: Reports of RCTs published in high-impact general and specialized medical journals were identified through a search of MEDLINE from January to March of 1995, 2000, 2005, and 2010. Articles that provided original data on adult patients diagnosed with chronic conditions were included in the study. Data on trial characteristics, reporting of allocation concealment, quality score, and the presence of a trial flow diagram were extracted independently by two reviewers, and discrepancies were resolved by consensus or independent adjudication. Descriptive statistics were used for quantitative variables. Comparisons between general medical and specialized journals, and trends over time were performed using Chi-square tests. RESULTS: Reports of 284 trials were analyzed. There was a significantly higher proportion of RCTs published with adequate reporting of allocation concealment (p = 0.003), presentation of a trial flow diagram (p

Sampling the microenvironment at sites of microbial exposure by dendritic cells (DC) and their subsequent interaction with T cells in the paracortical area of lymph nodes are key events for initiating immune responses. Most of our knowledge of such events in human is based on in vitro studies performed in the absence of extracellular matrix (ECM) proteins. ECM in basement membranes and interstitial spaces of different tissues, including lymphoid organs, plays an important role in controlling specific cellular functions such as migration, intracellular signalling and differentiation. The aim of this study was, therefore, to investigate the impact of two abundant ECM components, fibronectin and laminin, on the phenotypical and functional properties of DC and how that might influence DC induced T-cell differentiation.Human monocyte derived DC were treated with laminin and fibronectin for up to 48 hours and their morphology and phenotype was analyzed using scanning electron microscopy, flow cytometry and real time PCR. The endocytic ability of DC was determined using flow cytometry. Furthermore, co-culture of DC and T cells were established and T cell proliferation and cytokine profile was measured using H(3)-thymidine incorporation and ELISA respectively. Finally, we assessed formation of DC-T cell conjugates using different cell trackers and flow cytometry. Our data show that in the presence of ECM, DC maintain a 'more immature' phenotype and express higher levels of key endocytic receptors, and as a result become significantly better endocytic cells, but still fully able to mature in response to stimulation as evidenced by their superior ability to induce antigen-specific T cell differentiation.These studies underline the importance of including ECM components in in vitro studies investigating DC biology and DC-T cell interaction. Within the context of antigen specific DC induced T cell proliferation, inclusion of ECM proteins could lead to development of more sensitive assays.