Chloride Resistance of Concrete Containing Palm Oil Fuel Ash

Experimental study was conducted to investigate the chloride resistance of concrete containing palm oil fuel ash (POFA). Ground POFA was used to partially replace Portland cement Type I, by 20% by weight of binder in order to prepare POFA concrete.  Water cement ratio of 0.28 was used and high water reducing admixture was added to maintain workability. POFA concrete was investigated and tested for compressive strength at ages of 7, 28 and 90 days. Rapid chloride penetration test (ASTM C1202) and salt ponding test (ASTM C1543) were conducted on standard concrete specimens to investigate the chloride resistance of concrete.  The results showed that the compressive strength of POFA concrete was improved comparing with plain concrete. The results of chloride penetration tests revealed that significant improvement in terms of chloride resistance could be obtained by using 20 % of ground POFA in concrete mix as cementing replacement material

Methane Gas Hydrate Formation by Using Sodium Dodecyl Sulfate Additives

Gas Hydrates (G. Hyd) such as methane (CH4) hydrates are forming of water molecules in ice-like crystals (lattice shape) with cavities where the methane gas (gust gas) molecules are engaged in, and this process is conducted in a certain condition, mainly in low temperature and high pressure. The objective of the current work is to study the effect of Sodium Dodecyl Sulfate (SDS) additives on Methane gas hydrate performance. Two solutions were prepared. The first solution consists of distilled water (100 ml), methane gas and SDS additives (0.10 g). The second solution consists of same ingredient with seawater (100 ml) instead of distilled water. A stirred tank with 750 psi has been utilized. The highest recovery ratio was 42.15% for distilled water using SDS additives with a pressure cycle duration of 120 minutes. Significant improvement in the hydrate water recovery ratio can be obtained with distilled water and seawater by about 42 % and 15.6% respectively. Generally, SDS additives improve the recovery rate for water in the presence of methane

HCV Infection among Saudi Population: High Prevalence of Genotype 4 and Increased Viral Clearance Rate

HCV is a major etiological agent of liver disease with a high rate of chronic evolution. The virus possesses 6 genotypes with many subtypes. The rate of spontaneous clearance among HCV infected individuals denotes a genetic determinant factor. The current study was designed in order to estimate the rate of HCV infection and ratio of virus clearance among a group of infected patients in Saudi Arabia from 2008 to 2011. It was additionally designed to determine the genotypes of the HCV in persistently infected patients. HCV seroprevalence was conducted on a total of 15,323 individuals. Seropositive individuals were tested by Cobas AmpliPrep/Cobas TaqMan HCV assay to determine the ratio of persistently infected patients to those who showed spontaneous viral clearance. HCV genotyping on random samples from persistently infected patients were conducted based on the differences in the 5′untranslated region (5′UTR). Anti-HCV antibodies were detected in 7.3% of the totally examined sera. A high percentage of the HCV infected individuals experienced virus clearance (48.4%). HCV genotyping revealed the presence of genotypes 1 and 4, the latter represented 97.6% of the tested strains. Evidences of the widespread of the HCV genotype 4 and a high rate of HCV virus clearance were found in Saudi Arabia

Strength Capacity and Failure Mode of Shear Connectors Suitable for Composite Cold Formed Steel Beams: Numerical Study

In this paper, the findings of numerical modeling of the composite action between normal concrete and Cold-Formed Steel (CFS) beams are presented. To obtain comprehensive structural behavior, the numerical model was designed using 3-D brick components. The simulation results were correlated to the experimental results of eight push tests, using three types of innovative shear connectors in addition to standard headed stud shear connectors, with two different thicknesses of a CFS channel beam. The proposed numerical model was found to be capable of simulating the failure mode of the push test as well as the behavior of shear connectors in order to provide composite action between the cold-formed steel beam and concrete using the concrete damaged plasticity model

Chloride resistance of concrete containing palm oil fuel ash

Experimental study was conducted to investigate the chloride resistance of concrete containing palm oil fuel ash (POFA). Ground POFA was used to partially replace Portland cement Type I, by 20% by weight of binder in order to prepare POFA concrete. Water cement ratio of 0.28 was used and high water reducing admixture was added to maintain workability. POFA concrete was investigated and tested for compressive strength at ages of 7, 28 and 90 days. Rapid chloride penetration test (ASTM C1202) and salt ponding test (ASTM C1543) were conducted on standard concrete specimens to investigate the chloride resistance of concrete. The results showed that the compressive strength of POFA concrete was improved comparing with plain concrete. The results of chloride penetration tests revealed that significant improvement in terms of chloride resistance could be obtained by using 20 % of ground POFA in concrete mix as cementing replacement material

Guillain-Barré Syndrome Associated With Severe Acute Respiratory Syndrome Coronavirus 2 Detection and Coronavirus Disease 2019 in a Child

Coronavirus disease (COVID-19) is caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Physicians in China reported what is believed to be the first adult case of a SARS-CoV-2 infection associated with acute Guillain-Barré syndrome (GBS), followed by 5 adult Italian patients and another case in the United States. In the current report, we present one of the first descriptions of an association of GBS and SARS-CoV-2 infection in a child. In our facility, an 11-year-old boy presented with typical features of GBS and, after 5 days, a morbilliform skin rash over the palms of both hands. Three weeks before the start of the neurological symptoms, the boy had experienced an episode of mild febrile illness with mild respiratory manifestations and a persistent cough. The diagnosis of SARS-CoV-2 infection was confirmed by oropharyngeal swab on reverse-transcription polymerase chain reaction assay. The disease course of our patient strongly suggests a possible relationship between the development of GBS and SARS-CoV-2 infection. The case is discussed in view of previous case reports regarding the association of GBS and COVID-19

Pediatric Neurology Workforce in Saudi Arabia: A 5-Year Update

Background: The medical workforce plays a pivotal role in advancing human health, particularly within the healthcare system of Saudi Arabia. While government-employed healthcare providers form the central structure of the system and offer free healthcare services, the private healthcare sector is also witnessing significant growth. In parallel, the field of child neurology has experienced notable transformations in recent years, with continued expansion. This expansion brings forth a range of challenges for both current and future pediatric neurologists, necessitating careful consideration and proactive measures to address them. Aim of the study: To investigate and analyze the current characteristics of the workforce, with a specific focus on their employment status and related data. Methods: This is a cross-sectional analysis, using a survey to assess the distribution of pediatric neurologists in Saudi Arabia (SA). The final analytical sample included 82 subjects, working in 13 regions in SA. A descriptive analysis was used to address the study question. Results: The survey received responses from a total of 82 pediatric neurologists in Saudi Arabia (response rate 55%), with 38 (46%) being men and 44 (54%) being women. The mean age was 33 ± 1.225 years. The majority of participants practiced in major cities such as Riyadh and Jeddah. Nearly 50% of pediatric neurologists experienced some form of delay in obtaining their first job, ranging from 1 to 36 months. Conclusion: The landscape of the pediatric neurology workforce is currently witnessing noteworthy demographic shifts. With the majority of practitioners concentrated in major cities, there is an ongoing demand for qualified professionals in peripheral areas. This study describes the real-life challenges faced by pediatric neurologists, particularly the delay in securing employment after graduation, and underscores the critical importance of addressing these persistent issues along the journey of pediatric neurology