197 research outputs found
Novel Green Synthesis and Characterization of Nanopolymer Porous Gold Oxide Nanoparticles
Purpose: To develop a novel approach to green synthesis of nano-polymer porous gold oxide nanoparticles, and examine the effects of the temperatures on their surface.Methods: Green synthesis of nano-polymer porous gold oxide nanoparticles (GONPs) using cetyle trimethylammonium bromide (CTAB) surfactant with a mixture of Olea europaea fruit and Acacia Nilotica extracts, was performed using sol-gel method. The nanoporous particles were characterized by UV (ultraviolet (UV) visible spectroscopy and dynamic light scattering (DLS) while a zetasizer was applied to determine their average particle size. Their surface morphology and shape were assessed by transmission electron microscopy (TEM) and scanning election microscopy (SEM) while surface area was measured using nitrogen gas adsorption method.Results: TEM and SEM images showed a smooth, cylindrical or spherical, and cluster shapes, and porous surface morphology. Increase in calcination temperature resulted in increase in surface area and pore volume of nanoparticles. This feature yielded GONPs that were unique with a high surface area of 146.706 m2/g.Conclusion: The approach used in this study constitutes a new and rapid green synthesis of porous nanoparticles of gold oxide under simple conditions. Furthermore, increase in GONPs surface area is enhanced by increase in calcination temperature.Keywords: Gold oxide, Nanoporous, Green synthesis, Olea europaea, Acacia Nilotica, Surface area, Nanopolymer, Surface morpholog
The Gln27Glu Polymorphism in β2-Adrenergic receptor gene is linked to hypertriglyceridemia, hyperinsulinemia and hyperleptinemia in Saudis
<p>Abstract</p> <p>Background</p> <p>β2-adrenoceptor (β2AR) gene polymorphism glutamine 27 glutamic acid (Gln27Glu) and Arg16Gly were reported to have an association with obesity and obesity related disorders in some population. We evaluated Gln27Glu polymorphism in the β2AR gene in obese Saudi populations to investigate the association of β2AR gene with obesity and other related metabolic parameters.</p> <p>Design</p> <p>We studied possible association of Gln27Glu in β2AR gene with body mass index (BMI), anthropometric measurements and other metabolic parameters. The β2AR gene polymorphism (Gln27Glu) was identified by sequencing PCR products representing locus of interest. Based on BMI, the subjects were divided into three groups, normal weight, overweight and obese. The genotype and allele frequency were calculated separately for each group.</p> <p>Results</p> <p>The allelic frequency of Glu27 did not differ amongst the three groups, though the Glu27 homozygote (Glu/Glu) were more in obese subjects and had higher concentration of triglyceride, leptin and insulin compared to in the Gln27 heterozygotes and Gln/Gln homozygotes.</p> <p>Conclusions</p> <p>In this study we were able to provide evidence on the influence of Gln27Glu genetic variant of β2AR gene on lipid phenotypes, insulin and leptin levels in the Saudi populations.</p
Taxonomic Revision and Numerical Analysis of Hibiscus L. in Egypt
The development of agriculture over the last decades has resulted in a continuous change of the natural vegetation of Egypt. Several species widely cultivated as economic crops or ornamentals. Numbers of species which escaped from cultivation and naturalized in naturals habitats are increasing. It is necessary to study the changes in the natural vegetation and traces the new species. The present study undertakes a survey, taxonomical revision and numerical analysis of the genus Hibiscus L. in Egypt including wild and cultivated species. The taxonomic treatment based on collecting of fresh materials from the studied species, in addition to the investigation of the herbarium specimens as well as information from the literatures. Eleven species of Hibiscus were reported in this study, from which there are 5 wild species (H. diversifolius Jacq., H. micranthus L. f., H. vitifolius L., H. sabdariffa L. and H. trionum L.) and there are 6 cultivated species (H. cannabinus L., H. mutabilis L., H. rosa-sinensis L., H. schizopetalus (Mast.) Hook. f. in Curtis, H. syriacus L. and H. tiliaceus L.). An identification key to the species of Hibiscus is provided. Valid names and synonyms are updated from online sources. Scientific descriptions provided the characters of leaves, flowers, fruits and seeds based on the herbarium specimens and completed from fresh materials and literatures are given. Distribution of wild species in their phytogeographical regions are provided. Type specimen, habitat, selected specimens and economic importance are provided for each species. The numerical analysis based on thirty six morphological characters including vegetative, flowers and fruits parts of the studied species. SPSS Statistics version 22 used to get morphometric analysis. The numerical analysis revealed two main clusters. The first cluster included 3 species, viz. H. micranthus L. f., H. vitifolius L. and H. trionum L. The second cluster included two groups: group (a) viz. H. diversifolius Jacq., H. syriacus L., and H. tiliaceus L., and group (b) viz. Hibiscus cannabinus L., H. mutabilis L., H. rosa-sinensis L., H. sabdariffa L. and H. schizopetalus (Mast.) Hook. f. in Curtis
Effect of posture on swallowing.
Background: Swallowing is a systematic process. Any structural,
physiological or neurological disturbance in this process may cause
dysphagia. Although there are studies that report head/neck movements
during mastication, there are fewer studies that show the effect of
different head/neck postures on difficulty while swallowing.
Objectives: To observe the effect of different body postures on the
self-perceived difficulty while swallowing in normal healthy subjects.
Methods: Participants were asked to swallow 25 ml of water in one go
while sitting upright, sitting with head/neck flexed, head/ neck
extended and lying supine. Following this, they had to rate their
self-perceived difficulty while swallowing on a scale of 0-10, 0 being
most easy and 10 being most difficult. Results: 186 subjects with mean
age 32.7 SD 9.04 participated in this study. It was found to be least
difficult to swallow when subjects were asked to swallow in upright
sitting position. Statistically significant differences were found
between sitting upright, sitting with head/neck flexed, head/neck
extended and lying supine. Conclusion: Postural modification may help
in rehabilitation of patients with dysphagia by affecting bolus flow to
improve speed and safety of swallowing by closure of airways to prevent
aspiration
TOXICOLOGICAL AND PHARMACOLOGICAL ASSESSMENT OF GOLD NANORODS IN NORMAL RATS
Objective: assessment of acute, subchronic and chronic toxicity of pegylated gold nanorods (PEG-gold NRs) in Wistar rats of both sex in three routes of administration {intravenous (IV), intramuscular (IM) and subcutaneous (SC)}.Methods: in the acute toxicity study; PEG-gold NRs were injected once by three different routes, blood and tissue samples were collected after 14 d. In the subchronic and chronic studies; PEG-gold NRs were injected via three different routes, at 0.225, 0.45 and 0.9 mg/kg, once daily for 5 consecutive days, followed by a 23-day recovery period, for three and six months in the subchronic and chronic toxicity studies, respectively. Hematology, urinalysis, biochemical and histopathological examinations were conducted at the end of each study.Results: acute toxicity showed a significant decrease in serum triglycerides and cholesterol levels after single IV, IM and SC injection of PEG-gold NRs, while serum creatinine was significantly increased after IV and IM injection. Subchronic results revealed a significant decrease in serum triglycerides and cholesterol levels. The chronic study showed a significant decrease in serum triglycerides, sodium levels, total leukocytes count and significant increase in serum creatinine after IV injection. IM injection resulted in significant decrease in serum alkaline phosphatase, triglycerides, cholesterol, sodium levels and total leukocytes count. SC injection resulted in significant decrease in serum triglycerides, glucose, red blood cell count with increased creatinine and hematocrit.Conclusion: PEG-gold NRs at the three examined doses is apparently safe since no serious signs of toxicity were detected. IM and SC routes of injection were irritating, so we recommend the IV route.Ă‚
Malware detection issues, challenges, and future directions: A survey
The evolution of recent malicious software with the rising use of digital services has increased the probability of corrupting data, stealing information, or other cybercrimes by malware attacks. Therefore, malicious software must be detected before it impacts a large number of computers. Recently, many malware detection solutions have been proposed by researchers. However, many challenges limit these solutions to effectively detecting several types of malware, especially zero-day attacks due to obfuscation and evasion techniques, as well as the diversity of malicious behavior caused by the rapid rate of new malware and malware variants being produced every day. Several review papers have explored the issues and challenges of malware detection from various viewpoints. However, there is a lack of a deep review article that associates each analysis and detection approach with the data type. Such an association is imperative for the research community as it helps to determine the suitable mitigation approach. In addition, the current survey articles stopped at a generic detection approach taxonomy. Moreover, some review papers presented the feature extraction methods as static, dynamic, and hybrid based on the utilized analysis approach and neglected the feature representation methods taxonomy, which is considered essential in developing the malware detection model. This survey bridges the gap by providing a comprehensive state-of-the-art review of malware detection model research. This survey introduces a feature representation taxonomy in addition to the deeper taxonomy of malware analysis and detection approaches and links each approach with the most commonly used data types. The feature extraction method is introduced according to the techniques used instead of the analysis approach. The survey ends with a discussion of the challenges and future research directions
Green Synthesis, Characterization, and Antibacterial Activity of Silver/Polystyrene Nanocomposite
A novel, nontoxic, simple, cost-effective and ecofriendly technique was used to synthesize green silver nanoparticles (AgNPs). The AgNPs were synthesized using orange peel extract as a reducing agent for silver nitrate salt (AgNO3). The particle size distribution of AgNPs was determined by Dynamic Light Scattering (DLS). The average size of silver nanoparticles was 98.43 nm. The stable dispersion of silver nanoparticles was added slowly to polystyrene solution in toluene maintaining the temperature at 70°C. The AgNPs/polystyrene (PS) nanocomposite solution was cast in a petri dish. The silver nanoparticles encapsulated within polymer chains were characterized by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) equipped with Energy Dispersive Spectroscopy (EDS) in addition to Transmission Electron Microscopy (TEM). The green AgNPs/PS nanocomposite film exhibited antimicrobial activity against Gram-negative bacteria Escherichia coli, Klebsiella pneumoniae and Salmonella, and Gram-positive bacteria Staphylococcus aureus. Thus, the key findings of the work include the use of a safe and simple AgNPs/PS nanocomposite which had a marked antibacterial activity which has a potential application in food packaging
A systematic review of physical activity and sedentary behaviour research in the oil-producing countries of the Arabian Peninsula
ACE I/D Gene Polymorphism Can't Predict the Steroid Responsiveness in Asian Children with Idiopathic Nephrotic Syndrome: A Meta-Analysis
The results from the published studies on the association between
angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene
polymorphism and the treatment response to steroid in Asian children with
idiopathic nephrotic syndrome (INS) is still conflicting. This meta-analysis
was performed to evaluate the relation between ACE I/D gene polymorphism and
treatment response to steroid in Asian children and to explore whether ACE D
allele or DD genotype could become a predictive marker for steroid
responsiveness. = 0.85; respectively), however, the
result for the association of II genotype with SRNS risk was not stable.Our results indicate that D allele or DD homozygous can't become a
significant genetic molecular marker to predict the treatment response to
steroid in Asian children with INS
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