4,143 research outputs found
Variation in gas chromatography (GC) analysis in setting up laboratory protocols for waste to energy novel fixed bed reactor setups
Gas Chromatography coupled with Mass Spectrometry (GC/MS) has been applied in various analytical chemistry works. However, to fine tune a system that can serve the purposes of pyrolysis oil identification has proven to be a laborious effort, especially when considering the fact that no standard protocol exists for such analysis. In addition, obtained products were yielded from a newly commissioned unit with a unique and novel design. In this study, a US patent office claimed reactor [SULTAN-1, Pyrolysis Reactor System for the Conversion and Analysis of Organic Solid Waste, Patent application number: 15,487,351] that degrades polyolefinc virgin and waste materials to obtain petroleum refinery and petrochemical feedstock, has been commissioned. The reactor produces three distinct physical states of matter products accumulated as testing specimens, i.e. solids, gaseous and oil. The samples analysed in this work were of the gas and oil produced by pyrolysis of end of life tyre (ELTs) shavings that required to have a special recipe to work with in the laboratory. Various MS cords were utilised and experimental setups to fine tune the process, and special emphasis was given on the gas samples variation in this communication. To reach the desired analysis results with high repeatability, a plethora of experiences of lab personnel and laboratory-based experimental work was accumulated. Laboratory protocols were also setup for this work. These will be detailed along the process execution which yielded a standard laboratory best practice analytical method as part of the State of Kuwait newly initiated Government Initiative project
Lack of association between polymorphism rs540782 and primary open angle glaucoma in Saudi patients.
Background
To investigate whether polymorphism rs540782 on chromsome 1, in close proximity to the Zona Pellucida Glycoprotein 4 (ZP4) gene, is a risk factor for primary open angle glaucoma (POAG).
Method
The study genotyped 92 unrelated POAG cases and 95 control subjects from Saudi Arabia using Taq-Man® assay.
Results
The genotype frequency distribution did not deviate significantly from the Hardy-Weinberg equilibrium (p > 0.05). Overall, both the genotype and allele frequencies were not significantly different between cases and controls. The minor ‘C’ allele frequency was 49.4%, which was comparable to the Japanese population and higher than the Indian and Afro-Caribbean populations. Similarly, no significant association was found between genotypes and systemic diseases and health awareness/behavior domain variables. Importantly, glaucoma specific indices, such as intraocular pressure, cup/disc ratio and number of anti-glaucoma medication, also showed no statistically significant effect of genotypes within POAG cases.
Conclusion
Polymorphism rs540782 is not a risk factor for POAG in the Saudi cohort
Bi-allelic JAM2 Variants Lead to Early-Onset Recessive Primary Familial Brain Calcification.
Primary familial brain calcification (PFBC) is a rare neurodegenerative disorder characterized by a combination of neurological, psychiatric, and cognitive decline associated with calcium deposition on brain imaging. To date, mutations in five genes have been linked to PFBC. However, more than 50% of individuals affected by PFBC have no molecular diagnosis. We report four unrelated families presenting with initial learning difficulties and seizures and later psychiatric symptoms, cerebellar ataxia, extrapyramidal signs, and extensive calcifications on brain imaging. Through a combination of homozygosity mapping and exome sequencing, we mapped this phenotype to chromosome 21q21.3 and identified bi-allelic variants in JAM2. JAM2 encodes for the junctional-adhesion-molecule-2, a key tight-junction protein in blood-brain-barrier permeability. We show that JAM2 variants lead to reduction of JAM2 mRNA expression and absence of JAM2 protein in patient's fibroblasts, consistent with a loss-of-function mechanism. We show that the human phenotype is replicated in the jam2 complete knockout mouse (jam2 KO). Furthermore, neuropathology of jam2 KO mouse showed prominent vacuolation in the cerebral cortex, thalamus, and cerebellum and particularly widespread vacuolation in the midbrain with reactive astrogliosis and neuronal density reduction. The regions of the human brain affected on neuroimaging are similar to the affected brain areas in the myorg PFBC null mouse. Along with JAM3 and OCLN, JAM2 is the third tight-junction gene in which bi-allelic variants are associated with brain calcification, suggesting that defective cell-to-cell adhesion and dysfunction of the movement of solutes through the paracellular spaces in the neurovascular unit is a key mechanism in CNS calcification
A nationwide study on the knowledge, awareness, and practices towards COVID-19 in Saudi Arabia
Purpose: To investigate public knowledge, awareness and practice regarding COVID-19 in Saudi Arabia.Methods: A cross-sectional descriptive study was conducted, with a 16-item self-administered questionnaire. Data was collected using social media as the platform a day after the lockdown commenced in Saudi Arabia and data collection lasted from March 25 to April 25, 2020. Chi-square test was performed to determine the association between the variables.Results: The results showed that 96 % (n = 1505) of adults were aware of the clinical symptoms of COVID-19 and 57.9 % (n = 908) correctly identified that a stuffy nose and sneezing were less common in persons infected with the virus. A majority (95.4 %, n = 1495) agreed that there was no established therapeutic treatment for COVID-19. Further, 91.7 % (n = 1437) agreed that the virus could spread via respiratory droplets and only 46.2 % (n = 724) acknowledged that wearing face mask helped prevent transmission. The results also showed that 83.2 % (n = 1299) of the participants thought that visiting crowded places increased the likelihood of transmission.Conclusion: The findings of this study reveal that adults in Saudi Arabia are cognizant of COVID-19 and maintained good attitudes and practices regarding it. Furthermore, health education programs aimed at improving awareness of the disease and appropriate control measures will be beneficial in curbing the virus pandemic.
Keywords: Saudi Arabia, Coronavirus, Pandemic, COVID-19, Flu, Symptom
Your professionalism is not my professionalism:congruence and variance in the views of medical students and faculty about professionalism
Abstract Background Medical professionalism is an essential aspect of medical education and practice worldwide and it must be adopted according to different social and cultural contexts. We examined the current congruence and variance in the perception of professionalism in undergraduate medical students and faculty members in one medical school in Saudi Arabia. Methods The target population was first year to final year medical students of College of Medicine, King Saud University. Out of a total of 1431 students at College of Medicine 750 students (52 %) participated in the study. Fifty faculty members from clinical and non-clinical departments of the College of Medicine were randomly selected for this study and all participated in the study. The respondents recorded their responses through the Bristol online survey system, using a bilingual (English and Arabic) version of the Dundee Polyprofessionalism Inventory I: Academic integrity, which has 34 items. Results There are 17 lapses (50 % of the total) in professional behaviour where none of the faculty recommend the ignore sanction while students recommended a variable ignore sanction in a range of 6–29 % for different behaviours. Students and faculty recommended similar sanctions for 5 lapses (14.7 % of the total) in professional behaviours. Furthermore, there is statistically significant two level difference between the sanctions approved by faculty and students in the recommended sanctions for 12 lapses (35 % of the total (p < 0.050). Conclusions These results raised concerns in relation to the students’ understanding of professionalism. It is therefore, important to enhance their learning around the attributes of medical professionalism
Determination Of Aerosol Optical Thickness From Spectral Sky Transmittance.
The objective of this study is to test the feasibility of the proposed technique for retrieving spectral aerosol optical thickness (AOT) from the spectral transmittance measurements. The measurements have been acquired around Penang Island, Malaysia. Ground-based measurements were made with a handheld spectroradiometer. The measured spectral transmittance data were then converted to AOT values 6 spectral bands between 400 and 900 nm. Spectral AOT maps were generated using Kriging interpolation method for the 6 spectral bands. Air quality map was produced using this technique
Remote Sensing Of Turbidity Mapping From Digital Camera Imagery.
A complete set of normal digital camera data and ground-based measurements are used to test an algorithm for retrieval of turbidity distribution in the Prai Estuary, Penang, Malaysia
PM10 Retrieval From Spectroradiometer Measurements.
This study attempts to determine the aerosol optical thickness (AOT) from spectroradiometer data. The spectroradiometer is used to measure the atmospheric transmittances in a wide spectrum over Penang Island, Malaysia
Comparison and Determine Characteristics Potentials of HOMO/ LUMO and Relationship between Ea and Ip for Squaraine Dyes (SQ1, SQ2) by Using Cyclic Voltammetry and DFT/TD-DFT
The electrochemical properties of the squaraine dyes (SQ1 & SQ2) were investigated. The effects of the chemical structures of two SQ1&SQ2 dyes were selected in relation to the variable property of -COOH substituent for SQ1 compared to SQ2 which is without substituent and determine their potential energy levels in ground and excited states HOMO and LUMO. The HOMO energy levels of the SQ1 & SQ2 dyes are -5.19 eV and -5.16 eV. The LUMO energy levels are calculated to be -3.08 eV and -3.1eV respectively. The ground state geometry has been computed by applying density functional theory (DFT). The excitation energy was calculated by using time-dependent (DFT-TD) at DFT/B3LYP/6-31G** level of theory. The -COOH substituent affect the potential values, but the effect is small. The Ip range from -4.901 to -6.072 eV for SQ1 and -4.971 to -6.362 eV for SQ2 showed that the -COOH acid substituent exert a small effect on the frontier orbital energy level. The relationship between Ea and Ip was evaluated as a good slope 0.99 between HOMO and LUMO for SQ1& SQ2, this implies the feasibility and validity of the theoretical estimation and the experimental determination
Measurement of the cross-section and charge asymmetry of bosons produced in proton-proton collisions at TeV with the ATLAS detector
This paper presents measurements of the and cross-sections and the associated charge asymmetry as a
function of the absolute pseudorapidity of the decay muon. The data were
collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with
the ATLAS experiment at the LHC and correspond to a total integrated luminosity
of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements
varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the
1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured
with an uncertainty between 0.002 and 0.003. The results are compared with
predictions based on next-to-next-to-leading-order calculations with various
parton distribution functions and have the sensitivity to discriminate between
them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables,
submitted to EPJC. All figures including auxiliary figures are available at
https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13
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