35 research outputs found
Reconstructing the Poynting vector skew angle and wave-front of optical vortex beams via two-channel moir\'e deflectometery
A novel approach based on the two-channel moir\'e deflectometry has been used
to measure both wave-front and transverse component of the Poynting vector of
an optical vortex beam. Generated vortex beam by the q-plate, an inhomogeneous
liquid crystal cell, has been analyzed with such technique. The measured
topological charge of generated beams are in an excellent agreement with
theoretical prediction.Comment: 3 pages, 2 figure
Comparison of Micro-Shear Bond Strength of Resin Cement to Zirconia With Different Surface Treatments Using Universal Adhesive and Zirconia Primer
Introduction: Increased demand for metal free fixed partial denture in recent years led to the developing of all ceramic material with excellent mechanical properties. One of the most popular all ceramic is zirconia which shows poor bonding properties. Recently, universal primer contains of silane and phosphate monomer for bond to zirconia have been introduced. The aim of this study is determination of the best method for bonding to zirconia based on the selection of the correct primer, suitable adhesive and best surface pretreatment.Methods: In this in vitro experimental study 16 sintered-zirconia blocks prepared in dimension of (18×6×2 mm) by CAD/CAM technology. Sample cleansed by ultrasonic device contain of 96% ethanol in 6 minutes, after air-drying, based on surface treatment randomly divided into 4 groups which each group divided into 2 sub-groups based on the use of a primer or universal bond: (1) no treatment: (a) cement + zirconia primer, (b) cement + universal bond. (2) Alumina pretreatment: (a) cement + zirconia primer, (b) cement + universal bond. (3) Cojet sand pretreatment: (a) cement + zirconia primer, (b) cement + universal bond. (4) laser pretreatment (a) cement + zirconia primer, (b) cement + universal bond. Composite disc prepared with condensation of composite resin in Tygon tube with integral diminution of 0.7 mm which cured for 40 sconds. Universal bond or zirconia primmer apply on the surface of the zirconia samples then cemented to composite disks by Panavia F2 according manufacture instructions. Micro-shear bond strength determined with universal testing machine. Failure mode assessed under stereomicroscope. Selected sample based on surface treatment evaluated under SEM. Data were analyzed using one-way analysis of variance (ANOVA).Results: Comparison of the 4 surface treatment groups revealed a significant difference and the highest bond belonged to Cojet and the lowest one to laser group.Conclusion: It seems that Universal Adhesive can to be considered as an alternative to bond to zirconia but the Cojet method is still required
Effectiveness of Cue-Exposure Therapy on Alcohol Craving in Virtual Environment: Based on habit loop
Background: In the treatment and abstinence of alcoholism, especially in abstinence after treatment, "Craving" has an essential role. Thus, our aim was to examine the effect of cue-exposure therapy on alcohol craving in virtual environment based on the habit loop.Methods: The present investigation was a case-control experimental study with a pretest–posttest–5 weeks follow–up design. Research population were alcohol-addicted people hospitalized in a psychiatric hospital. We had 62 subjects who had abstained from alcohol consumption. The sampling method was convenience sampling and the sample allocation was randomized and matched. The intervention was VR-CET that was implemented in eight sessions. Penn Alcohol Craving Scale, Alcohol Urge Questionnaire, and Obsessive Compulsive Drinking Scale were used to collect the data. In order to analyze the data, analysis of covariance (ANCOVA) in SPSS V.23 was performed.Findings: Our results showed that after implementation of VR-CET program the rate of PACS reduced significantly in posttest stage (p = 0.01) and follow up stage (p= 0.05). Also, the rate of AUQ and OCDS after exposure to VR-CET program declined significantly. The significant level of AUQ and OCDS in posttest and follow up stages were set at p- value < 0.01 and p-value <0.05 respectively.Conclusion: VR-CET program can reduce alcohol craving by paying attention to various cues and contexts. In fact, it would be more beneficial if the treatment environment resembles a conditioned context and contains as many related cues as possible
The Relationship between Development Indices and Children’s Growth Among Under 12-Month-Old Children in Markazi Province, Iran
Background: The factors affecting children’s growth and development have been discussed in various research studies. This study evaluates the association between growth and development of under 12-month-old children in Iran.Methods: This cross-sectional study uses the Ages & Stages Questionnaire (ASQ) data and demographic characteristics in the child's health records of 15,885 Iranian children in Arak city up to March 2017. The impact of growth disorder, type of delivery, preterm birth, at birth weight/height/head circumference, gross motor, problem-solving, personal-social, communication, and fine motor on the participants’ head circumference/weight/height was assessed. Unadjusted analyses were done using independent sample t-test, Pearson correlation test and one-way analysis of variance. Multiple multivariate regression was utilized for adjusted effects. P-values less than 0.05 were considered statistically significant.Results: Head circumference was associated with growth disorder, type of delivery, and preterm birth. Children with known and unknown growth disorders had 610.19 and 160.58 grams less weight than those without any growth disorder. Gross motor and personal-social aspects of ASQ were found to be associated with weight at the age of 12-month old. Height at 12-months was affected by growth disorder, gross motor, personal-social, communication, and fine motor.Conclusion: Results of this study show that cesarean type of delivery, preterm birth, and low birth weight are the impacting factors associated with negative children growth trends and lower developmental status at the age of 12 months
Pretreatment of lignocelluloses for enhanced biogas production: A review on influencing mechanisms and the importance of microbial diversity
Received 13 August 2019; Received in revised form 10 July 2020; Accepted 28 July 2020, Available online 11 August 2020.As one of the most efficient methods for waste management and sustainable energy production, anaerobic
digestion (AD) countenances difficulties in the hydrolysis of lignocelluloses biomass. Different pretreatment
methods have been applied to make lignocelluloses readily biodegradable by microorganisms. These pretreatments
can affect biogas yield by different mechanisms at molecular scale, including changes in chemical
composition, cellulose crystallinity, degree of polymerization, enzyme adsorption/desorption, nutrient accessibility,
deacetylation, and through the formation of inhibitors. The present article aims at critically reviewing the
reported molecular mechanisms affecting biogas yield from lignocelluloses via different types of pretreatments.
Then, a new hypothesis concerning the impact of pretreatment on the microbial community developed
(throughout the AD process from an identical inoculum) was also put forth and was experimentally examined
through a case study. Four different leading pretreatments, including sulfuric acid, sodium hydroxide, aqueous
ammonia, and sodium carbonate, were performed on rice straw as model lignocellulosic feedstock. The results
obtained revealed that the choice of pretreatment method also plays a pivotally positive or negative role on
biogas yield obtained from lignocelluloses through alteration of the microbial community involved in the AD.
Considerable changes were observed in the archaeal and bacterial communities developed in response to the
pretreatment used. Sodium hydroxide, with the highest methane yield (338 mL/g volatile solid), led to a partial
switch from acetoclastic to the hydrogenotrophic methane production pathway. The findings reported herein undermine the default hypothesis accepted by thousands of previously published papers, which is changes in
substrate characteristics by pretreatments are the only mechanisms affecting biogas yield. Moreover, the results
obtained could assist with the development of more efficient biogas production systems at industrial scale by
offering more in-depth understanding of the interactions between microbial community structure, and process
parameters and performance
Mortality patterns in patients with Staphylococcus aureus bacteremia during the COVID-19 pandemic: Predictors and insights
Objectives: This paper aims to determine the Staphylococcus aureus bacteremia (SAB) in-hospital mortality rate and its associated risk factors during the COVID-19 pandemic. Methods: A total of 167 SAB samples were collected between March 2020 and March 2022 at a teaching hospital in Tehran, Iran. The patient's baseline data and antibiograms were collected. The outcome of the study was in-hospital mortality. Results: The overall in-hospital mortality rate was 41.9 %, with higher mortality observed in patients over 60 years old (P = 0.032), those with community-acquired Staphylococcus aureus bacteremia (P = 0.010), and those admitted to the ICU (P = 0.016). Antibiotic resistance profiles indicated a higher mortality in resistant S.aureus strains but only significant for ciprofloxacin (P = 0.001), methicillin (P = 0.047), and sulfamethoxazole (P = 0.023). Multivariate analysis identified age, sex, ICU admission, and the source of bacteremia as independent predictors of mortality, while COVID-19 coinfection and resistance to antibiotics were not found to be significant predictors. Conclusion: SAB remains a challenging infection that is amplified by the pandemic. Older age and ICU admission are significant mortality predictors. In settings with a high prevalence of MRSA, factors like age, sex, and quality of care outweigh pathogen-related factors such as antibiotic resistance
Mast Cell Tryptase and Implications for SARS-CoV-2 Pathogenesis
Mast cells (MCs) are heterogenous innate leukocytes producing many inflammatory mediators during viral infections that can be protective or damaging to the host, as is seen in the infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pathogen responsible for the coronavirus disease that was first identified in 2019 (COVID-19). MCs can sense viruses by diverse mechanisms. They express angiotensin-converting enzyme 2 (ACE2), known as the principal entry receptor for SARS-CoV-2, and tryptase that can promote SARS-CoV-2 infection. Tryptase is one of the most abundant serine proteases released by MCs during degranulation and is reported to have both beneficial and detrimental roles in respiratory diseases. Reviewed here are the potential roles of MC-derived tryptase during COVID-19, the implications it has in the pathogenesis of SARS-CoV-2, and the possibility of treating COVID-19 by targeting tryptase
Prevalence of Antibiotics Consumption in Children in Central Iran: 2019-2020
Background: One of the challenges in medicine has been the exaggerated use of antibiotics. The purpose of this study was to investigate the prevalence of antibiotic usage in children in Arak, Iran (2019-2020) to determine the factors related to antibiotic prescription and consumption in children.
Methods: This was a population based, cross-sectional study conducted in Arak, the capital city of Markazi Province, Iran. Stratified random sampling was applied to recruit children who were up to five years old, and registered in the healthcare system between Jan. 2019 and Jan. 2020. A response rate of 85% was obtained from the subjects’ parents. Face-to-face interviews were used to collect the data from the children’s mothers. Univariate and adjusted linear regression analyses were applied to assess the determinants of antibiotic consumption in these children.
Results: A total of 1483 children were enrolled in the study; most of them were boys with the mean age of 2.1±1.5 years old. The annual prevalence of antibiotic consumption in Arak was found to be 62.4% for at least one antibiotic. The most consumed antibiotic was azithromycin (24.2%). Among antibiotic groups, the most consumed group was macrolides (26.9%). Upon multiple logistic regression analyses, a lower consumption rate was observed among the younger children with older mothers, and children whose fathers had permanent jobs than other children groups. A higher consumption rate was observed among families with higher parity.
Conclusion: The annual prevalence of antibiotic consumption in this study was very high, with the most consumed drug being azithromycin. We recommend that the use of antibiotics be reconsidered by drawing future healthcare policies, aiming at reducing the heavy antibiotics consumption in children
Dendritic Cell-Based Vaccines Recruit Neutrophils to the Local Draining Lymph Nodes to Prime Natural Killer Cell Responses
Dendritic cell (DC)-based cancer vaccines are a form of immunotherapy that activates the innate and adaptive immune systems to combat cancers. Neutrophils contribute to cancer biology and have the potential to be exploited by immunotherapeutic platforms to enhance anti-tumor immune responses. We previously showed that DC vaccines elicit the expansion of mouse interferon (IFN)γ-producing mature natural killer (NK) cells to elevate anti-tumor responses. Here, we demonstrate the rapid recruitment of neutrophils to the draining lymph nodes of DC-vaccinated mice. This was accompanied by an increase in the total number of NK cells producing IFNγ and expressing CD107a, a marker of degranulation that demonstrates NK cell functional activity. Furthermore, the depletion of neutrophils in DC-immunized mice resulted in decreased numbers of NK cells in draining lymph nodes compared to the controls. Interestingly, the increased number of IFNγ- and CD107a-expressing NK cells in DC-immunized mice was not detected in mice depleted of neutrophils. Further investigations showed that DC vaccines induced IFNγ− and TNFα-producing CD8+ T cells that also expressed CD107a, but depletion of neutrophils did not have any impact on the CD8+ T cell population. Our findings suggest that neutrophil-mediated anti-tumor immunity induced by a DC vaccine platform could be targeted to provide innovative strategies to enhance its clinical efficacy