Theoretical and experimental analysis of the physical behavior of gaskets in shock absorber

The current study examines the theoretical and experimental behaviour of gaskets when using different cases of disc samples (free-free, free-fix and fix-fix). The samples are made of rubber. The deformation of the gasket as a function of loading depends significantly on how it is fixed to the rigid supports. Physical properties have been explained. In experimental analysis of the sample disc "Free-Free", the loading velocity does not have a significant influence on the range of values of the mentioned velocity. All the curves in the "Free-Fix" disc load illustrate that at the same deformation, the average pressure is higher than in the case of the "free-free" disc. At the deformation of 1.49 mm, the average pressure is 33% higher than all other graphs. In the case of the "Fix-Fix" disc, it is observed that the load, evaluated by the average pressure, is clearly higher than in the case "Free-Fix" disc. At a deformation of 1.49 mm, the average pressure was found to be 15 times higher

Study the Effect of adding Polyacrylamide on Rheological and Mechanical Properties of Carboxymethyle cellulose Polymer as aqueous solutions

In this paper, we investigated the Rheological and mechanical  properties of Carboxymethyle cellulose dissolves in distilled water at different concentrations (0.1%, 0.2%, 0.3%, 0.4% ,0.5 ,%,0.6 %,0.7% and 0.8%) (gm./ml) before and after adding (0.5, 1) gm. of PAAM for all concentrations, the Rheological properties such as shear viscosity, relative viscosity, specific viscosity, reduced viscosity and Viscosity Average Molecular weight are measured, all the viscosities depend on density and concentration, The results show that adding PAAM lead to increase the values of different types of viscosities then chose before. Also the research included study of the Mechanical properties by ultrasonic waves velocity technique at frequency( 25 KHz), these properties are absorption coefficient of ultrasonic waves, relaxation time, relaxation amplitude, specific acoustic impedance, compressibility, and bulk modules had been measured and all the results showed that all properties are increasing with the increase of the polymer concentration except compressibility is decreasing with the increase of the concentration before and after adding PAAM. Keywords: Carboxymethyle cellulose, Polyacrylamide ,Rheological properties, Mechanical properties

Descriptive study of the species Limnophora Robineau-Desvoidy 1830 (Diptera:Muscidae) in Iraq – Kerbala

The current study was conducted during the year 2020 in some areas of the holy Kerbala governorate with the aim of diagnosing some species of insects of environmental and biological importance and knowing their distribution and the time of occurrence during seasons. The results showed that the species Limnophora obsignata (Rondani, 1866) (Muscidae: Coenosiinae) was recorded for the first time in Iraq. It was found that throughout the study period, this species was more frequently found in river habitats and seasons with moderate temperatures and humidity (spring and autumn). The external appearance of this species was described, as well as the anatomy of the male reproductive system of the samples

The possible association between Chlamydia pneumoniae infection and asthma.

Background: Many etiological factors have been implicated in the pathogenesis of Asthma like; viruses, bacteria and Chlamydia pneumoniae. This study focuses on the role of Chlamydia pneumoniae in asthma pathogenesis. Patients and Methods: The detection of Anti-Chlamydia pneumoniae antibodies IgA, IgM and IgG in patients by ELISA, for 35 patients, 18 asthmatic patients, 12 patients with chest infection with no history of asthma, and 5 apparently healthy as control subjects. Results: The results showed that 80% and 70% of the patients were negative for anti- Chlamydia pneumonia antibodies IgA and IgM respectively, while significantly (p<0.05) high number (73%) of patients were positive for IgG, of which significant number (p<0.05) of them, 63% were asthmatic and 36% were non-asthmatic chest infection. Conclusion: this study may support the association between Chlamydia pneumoniae and asthma

ASSOCIATION BETWEEN AGE, BODY MASS INDEX, WAIST CIRCUMFERENCE, LIPID PROFILE PARAMETERS, AND SYMPTOMATIC BACTERIAL URINARY TRACT INFECTION IN IRAQI ADULT WOMEN

ABSTRACTObjective: This study was conducted to investigate the association between age, body mass index (BMI), waist circumference (WC), and incidence ofsymptomatic bacterial urinary tract infections in adult women and to study the impact of infection on lipid profile.Methods: A total of 30 women enrolled with symptomatic bacterial urinary tract infections and 10 healthy women as control group. Mid-stream urinesamples were submitted. BMI, WC, and lipid profile were measured. Both leukocyte esterase and nitrite tests were used to diagnose the urinary tractinfection, and viable quantification was done as confirmatory for the diagnosis.Results: Revealed that there was a significant relationship between the incidence of symptomatic bacterial urinary tract infections and age groups(p=0.04) as age group (21-30) years recorded the highest percentage (33.33%) followed by the age group (31-40) which recorded 30%. No significantassociation was found between BMI, WC and incidence of symptomatic bacterial urinary tract infections (p=0.08, p=0.14) respectively. Comparedto healthy control group, there was a significant decrease in the levels of total cholesterol, triglycerides, high-density-lipoprotein, very-low-densitylipoprotein,and low-density-lipoprotein (p=0.0001, p=0.006, p=0.001, p=0.006, and p=0.0001), respectively.Conclusion: The young women were significantly susceptible to symptomatic bacterial urinary tract infections than other age groups. Both BMI andWC were not significant indicators for the incidence of symptomatic bacterial urinary tract infections in adult women. Adult women with symptomaticbacterial urinary tract infections showed a significant decrease in lipid profile parameters when compared with the control healthy adult women.Keywords: Age, Body mass index, Waist circumference, Lipid profile, Urinary tract infections

Electrically Tunable Scattering from Devitrite–Liquid Crystal Hybrid Devices

Devitrite is normally an unwanted crystalline impurity in the soda-lime-silica glass making process. Thin needles formed by heterogeneous nucleation of devitrite on the glass surface provide unique birefringence properties for potential applications in tunable optical devices. Here, devitrite and a liquid crystal are combined to create an electrically variable optical diffuser. The magnitude and scattering angle of the transmitted light propagating through the diffuser are tuned by varying the voltage between the graphene and indium tin oxide electrodes on either side of the liquid crystal. The threshold voltage to switch the transmitted light from a predominantly horizontal diffusion to a random order is 3.5 V. Angle-resolved measurements show broad diffusion angles of transmitted light with a maximum deflection of ±60°. The dynamically tunable devitrite-liquid crystal hybrid devices may advance the development of currently less viable technologies including beam shaping and automatic light transmission control.Leverhulme Trust, Royal Society, Engineering and Physical Sciences Research Council (IAA Follow on Fund

Structure-based enzyme engineering improves donor-substrate recognition of Arabidopsis thaliana Glycosyltransferases

Glycosylation of secondary metabolites involves plant UDP-dependent glycosyltransferases (UGTs). UGTs have shown promise as catalysts in the synthesis of glycosides for medical treatment. However, limited understanding at the molecular level due to insufficient biochemical and structural information has hindered potential applications of most of these UGTs. In the absence of experimental crystal structures, we employed advanced molecular modelling and simulations in conjunction with biochemical characterisation to design a workflow to study five Group H Arabidopsis thaliana (76E1, 76E2, 76E4, 76E5, 76D1) UGTs. Based on our rational structural manipulation and analysis, we identified key amino acids (P129 in 76D1; D374 in 76E2; K275 in 76E4), which when mutated improved donor-substrate recognition than wildtype UGTs. Molecular dynamics simulations and deep learning analysis identified structural differences, which drive substrate preferences. The design of these UGTs with broader substrate specificity may play important role in biotechnological and industrial applications. These findings can also serve as basis to study other plant UGTs and thereby advancing UGT enzyme engineering.Federal Scholarship Board/Presidential Special Scholarship Scheme for Innovation and Development (PRESSID), Nigeria; Sichuan Science and Technology Progra

Nr2e3 is a Genetic Modifier That Rescues Retinal Degeneration and Promotes Homeostasis in Multiple Models of Retinitis Pigmentosa

Recent advances in viral vector engineering, as well as an increased understanding of the cellular and molecular mechanism of retinal diseases, have led to the development of novel gene therapy approaches. Furthermore, ease of accessibility and ocular immune privilege makes the retina an ideal target for gene therapies. In this study, the nuclear hormone receptor gene Nr2e3 was evaluated for efficacy as broad-spectrum therapy to attenuate early to intermediate stages of retinal degeneration in five unique mouse models of retinitis pigmentosa (RP). RP is a group of heterogenic inherited retinal diseases associated with over 150 gene mutations, affecting over 1.5 million individuals worldwide. RP varies in age of onset, severity, and rate of progression. In addition, ~40% of RP patients cannot be genetically diagnosed, confounding the ability to develop personalized RP therapies. Remarkably, Nr2e3 administered therapy resulted in reduced retinal degeneration as observed by increase in photoreceptor cells, improved electroretinogram, and a dramatic molecular reset of key transcription factors and associated gene networks. These therapeutic effects improved retinal homeostasis in diseased tissue. Results of this study provide evidence that Nr2e3 can serve as a broad-spectrum therapy to treat multiple forms of RP

Nuclear Receptor Rev-erb Alpha (Nr1d1) Functions in Concert with Nr2e3 to Regulate Transcriptional Networks in the Retina

The majority of diseases in the retina are caused by genetic mutations affecting the development and function of photoreceptor cells. The transcriptional networks directing these processes are regulated by genes such as nuclear hormone receptors. The nuclear hormone receptor gene Rev-erb alpha/Nr1d1 has been widely studied for its role in the circadian cycle and cell metabolism, however its role in the retina is unknown. In order to understand the role of Rev-erb alpha/Nr1d1 in the retina, we evaluated the effects of loss of Nr1d1 to the developing retina and its co-regulation with the photoreceptor-specific nuclear receptor gene Nr2e3 in the developing and mature retina. Knock-down of Nr1d1 expression in the developing retina results in pan-retinal spotting and reduced retinal function by electroretinogram. Our studies show that NR1D1 protein is co-expressed with NR2E3 in the outer neuroblastic layer of the developing mouse retina. In the adult retina, NR1D1 is expressed in the ganglion cell layer and is co-expressed with NR2E3 in the outer nuclear layer, within rods and cones. Several genes co-targeted by NR2E3 and NR1D1 were identified that include: Nr2c1, Recoverin, Rgr, Rarres2, Pde8a, and Nupr1. We examined the cyclic expression of Nr1d1 and Nr2e3 over a twenty-four hour period and observed that both nuclear receptors cycle in a similar manner. Taken together, these studies reveal a novel role for Nr1d1, in conjunction with its cofactor Nr2e3, in regulating transcriptional networks critical for photoreceptor development and function

Extracting scientific trends by mining topics from Call for Papers

© 2019, Emerald Publishing Limited. Purpose: The purpose of this paper is to present a novel approach for mining scientific trends using topics from Call for Papers (CFP). The work contributes a valuable input for researchers, academics, funding institutes and research administration departments by sharing the trends to set directions of research path. Design/methodology/approach: The authors procure an innovative CFP data set to analyse scientific evolution and prestige of conferences that set scientific trends using scientific publications indexed in DBLP. Using the Field of Research code 804 from Australian Research Council, the authors identify 146 conferences (from 2006 to 2015) into different thematic areas by matching the terms extracted from publication titles with the Association for Computing Machinery Computing Classification System. Furthermore, the authors enrich the vocabulary of terms from the WordNet dictionary and Growbag data set. To measure the significance of terms, the authors adopt the following weighting schemas: probabilistic, gram, relative, accumulative and hierarchal. Findings: The results indicate the rise of “big data analytics” from CFP topics in the last few years. Whereas the topics related to “privacy and security” show an exponential increase, the topics related to “semantic web” show a downfall in recent years. While analysing publication output in DBLP that matches CFP indexed in ERA Core A* to C rank conference, the authors identified that A* and A tier conferences not merely set publication trends, since B or C tier conferences target similar CFP. Originality/value: Overall, the analyses presented in this research are prolific for the scientific community and research administrators to study research trends and better data management of digital libraries pertaining to the scientific literature