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2024 ◽  
Vol 84 ◽  
Author(s):  
R. M. Santos ◽  
A. C. Petry ◽  
V. L. Sousa ◽  
H. O. Souza ◽  
A. Azevedo ◽  
...  

Abstract Petroleum water soluble fraction (WSF) impairs organisms, but damages may vary among cell and tissue levels. The aim of the present study was to evaluate the acute (24 h, 48 h, 72 h) and subchronic effects (36 days) of WSF (0%, 25% and 100%) in juveniles of the Neotropical top predator fish Hoplias aff. malabaricus. The effects of WSF were evaluated at a molecular level using the comet assay and micronucleus test for genome damage; and at a morphological level through histological identification of liver pathologic lesions. In both acute and subchronic exposure we found low levels of DNA damage (< 10% of comet tail) and non-significant frequency of micronucleus in WSF exposed fish. The most significant liver lesions in WSF exposed fish were fatty vacuolization, hypertrophy and focal necrosis. Since these tissue injuries were progressive and persistent, their irreversibility may negatively affect fish recruitment, even in a such resistant top predator.


2022 ◽  
Vol 11 (1) ◽  
pp. 79
Author(s):  
María Ángeles Turrado-Sevilla ◽  
Isabel Cantón-Mayo

The creation and implementation of innovation proposals in education can provide a new key towards sustainable development. We are aware that schools perform very different innovations but often, with very low levels of impact and dissemination in their community. There are not many studies that describe, put a value on, categorize or analyse the innovations. This study sought to gain insight into the ICT innovations produced in Spanish primary and pre-primary schools. A quantitative approach based on a questionnaire was used to collect the data, named MANEDUIN, completed by 86 teachers selected by stratified random sampling (public - private, rural - urban). The reliability and the construct-related validity was evaluated from the questionnaire and the validity of content decided by means of experts’ judgment. Our findings point to a good consistency in the questionnaire (Cronbach’s Alpha: 0.848). The descriptive statistics and the analysis were made by factorial categories. The results of the factorial analysis confirm the dimensions proposed in the design of the questionnaire in the categories of the factors included in the innovation (social cohesion, interaction with the community, technologies, and success), the innovative schools and their characteristics, the topic and the type of innovation (on resources, direction, materials and time), as well as the obstacles to the innovation. This paper concludes that the questionnaire MANEDUIN is a valid and reliable tool to measure the management of schools’ innovations.


2022 ◽  
Vol 7 (4) ◽  
pp. 687-690
Author(s):  
Vishaka Naik ◽  
Ugam P .S Usgaonkar

To evaluate in intraoperative complications of MSICS performed by Junior Residents and to compare the incidences of major complications in the first six months of training versus last six months of training.It is a retrospective type of study. From March 2018 to February 2019 a total of 293 manual SICS were conducted by the Junior Residents in Department of Ophthalmology. Each of the patients underwent a detailed ophthalmological examination preoperatively and underwent MSICS under peribulbar anesthesia. Consents for surgeries were obtained from each patient.Following intraoperative complications were noted: tunnel related complications, capsulorrhexis related complications, Iridodialysis, posterior capsular rent, zonular dialysis, vitreous leak, surgical aphakia, Descemet membrane detachment, placement of ACIOL, Nucleus drop and IOL drop. The patient’s immediate postoperative vision was also noted. SPSS version 15.0.Tunnel related complications were found in 13.98% patients either as scleral button holing or premature entry. Posterior capsular rents and bag disinsertion were found in total of 11.94% patients owing to which 3.07% were left aphakic. 63.13% patients had visual acuity better than 6/12 by snellens chart on first postoperative day. Performance of adequate anterior capsulotomy, minimal handling of the cornea and avoidance of posterior capsular rent are some of the challenges faced by the residents while learning MSICS. Stepwise supervised training can help a resident doctor master these steps while keeping the complications at acceptably low levels. Stepwise supervised training of residents performing MSICS can minimize complications


2022 ◽  
Author(s):  
Giulia Ada Corbet ◽  
James M Burke ◽  
Gaia Rachel Bublitz ◽  
Roy Parker

Mammalian cells respond to dsRNA in multiple manners. One key response to dsRNA is the activation of PKR, an eIF2α kinase, which triggers translational arrest and the formation of stress granules. However, the process of PKR activation in cells is not fully understood. In response to increased endogenous or exogenous dsRNA, we observed that PKR forms novel cytosolic condensates, referred to as dsRNA-induced foci (dRIFs). dRIFs contain dsRNA, form in proportion to dsRNA, and are enhanced by longer dsRNAs. dRIFs also enrich several other dsRNA-binding proteins including ADAR1, Stau1, NLRP1, and PACT. Strikingly, dRIFs correlate with and form prior to translation repression by PKR and localize to regions of cells where PKR activation is initiated. We suggest that dRIF formation is a mechanism cells utilize to enhance the sensitivity of PKR activation in response to low levels of dsRNA, or to overcome viral inhibitors of PKR activation.


2022 ◽  
Vol 12 ◽  
Author(s):  
Wael Bahnan ◽  
Sebastian Wrighton ◽  
Martin Sundwall ◽  
Anna Bläckberg ◽  
Olivia Larsson ◽  
...  

Spike-specific antibodies are central to effective COVID19 immunity. Research efforts have focused on antibodies that neutralize the ACE2-Spike interaction but not on non-neutralizing antibodies. Antibody-dependent phagocytosis is an immune mechanism enhanced by opsonization, where typically, more bound antibodies trigger a stronger phagocyte response. Here, we show that Spike-specific antibodies, dependent on concentration, can either enhance or reduce Spike-bead phagocytosis by monocytes independently of the antibody neutralization potential. Surprisingly, we find that both convalescent patient plasma and patient-derived monoclonal antibodies lead to maximum opsonization already at low levels of bound antibodies and is reduced as antibody binding to Spike protein increases. Moreover, we show that this Spike-dependent modulation of opsonization correlate with the outcome in an experimental SARS-CoV-2 infection model. These results suggest that the levels of anti-Spike antibodies could influence monocyte-mediated immune functions and propose that non-neutralizing antibodies could confer protection to SARS-CoV-2 infection by mediating phagocytosis.


2022 ◽  
Author(s):  
Aleksandr Bulaev

The goal of this research was to study pyrite (FeS2 ) bioleaching by a strain of the genus Acidiplasma under different conditions (temperature, pH) to evaluate the potential role of Acidiplasma representatives in biooxidation of this sulfide mineral. To compare the role of Acidiplasma archaea in pyrite biooxidation with other acidophilic microorganisms, the experiments were also performed with representatives of othergroups of microorganisms predominant in biohydrometallurgical processes.Pure and mixed cultures of moderately thermophilic acidophilic microorganisms, including strains Acidithiobacillus caldus MBC-1, Sulfobacillusthermosulfidooxidans VKMV 1269T and Acidiplasmasp. MBA-1, were used. The experiments were carried out in flasks with 100 mL of mineral nutrient medium supplemented with 0.02% yeast extract and 1 g of pyrite on a rotary shaker for 20 days. Bioleaching was performed at 45, 55, and 60∘С. The results demonstrated that the representatives of the genus Acidiplasmaprovided a comparatively higher rate of pyrite bioleaching at high temperatures (55 and 60∘C) and low pH of the medium (1.0). Thus, according to the results, strains of thegenus Acidiplasma may provide a high rate of pyrite bioleaching at low levels ofpH. Therefore, the results suggest that archaea of the genus Acidiplasma may be promising microorganisms to improve bioleaching processes with an increase in the operational temperature, which is usually maintained at 40–45∘C in industrial-scale reactors. Keywords: biomining, bioleaching, acidophilic microorganisms, sulfide minerals, pyrite


Author(s):  
Luiz Vitiello ◽  
Ser-Huang Poon

AbstractBased on a standard general equilibrium economy, we develop a framework for pricing European options where the risk aversion parameter is state dependent, and aggregate wealth and the underlying asset have a bivariate transformed-normal distribution. Our results show that the volatility and the skewness of the risk aversion parameter change the slope of the pricing kernel, and that, as the volatility of the risk aversion parameter increases, the (Black and Scholes) implied volatility shifts upwards but its shape remains the same, which implies that the volatility of the risk aversion parameter does not change the shape of the risk neutral distribution. Also, we demonstrate that the pricing kernel may become non-monotonic for high levels of volatility and low levels of skewness of the risk aversion parameter. An empirical example shows that the estimated volatility of the risk aversion parameter tends to be low in periods of high market volatility and vice-versa.


Vaccines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 110
Author(s):  
Choudhary Sobhan Shakeel ◽  
Amenah Abdul Mujeeb ◽  
Muhammad Shaheer Mirza ◽  
Beenish Chaudhry ◽  
Saad Jawaid Khan

COVID-19 vaccines have met varying levels of acceptance and hesitancy in different parts of the world, which has implications for eliminating the COVID-19 pandemic. The aim of this systematic review is to examine how and why the rates of COVID-19 vaccine acceptance and hesitancy differ across countries and continents. PubMed, Web of Science, IEEE Xplore and Science Direct were searched between 1 January 2020 and 31 July 2021 using keywords such as “COVID-19 vaccine acceptance”. 81 peer-reviewed publications were found to be eligible for review. The analysis shows that there are global variations in vaccine acceptance among different populations. The vaccine-acceptance rates were the highest amongst adults in Ecuador (97%), Malaysia (94.3%) and Indonesia (93.3%) and the lowest amongst adults in Lebanon (21.0%). The general healthcare workers (HCWs) in China (86.20%) and nurses in Italy (91.50%) had the highest acceptance rates, whereas HCWs in the Democratic Republic of Congo had the lowest acceptance (27.70%). A nonparametric one-way ANOVA showed that the differences in vaccine-acceptance rates were statistically significant (H (49) = 75.302, p = 0.009*) between the analyzed countries. However, the reasons behind vaccine hesitancy and acceptance were similar across the board. Low vaccine acceptance was associated with low levels of education and awareness, and inefficient government efforts and initiatives. Furthermore, poor influenza-vaccination history, as well as conspiracy theories relating to infertility and misinformation about the COVID-19 vaccine on social media also resulted in vaccine hesitancy. Strategies to address these concerns may increase global COVID-19 vaccine acceptance and accelerate our efforts to eliminate this pandemic.


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