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The relevance of the article is caused by the growth of lower olefins consumption as valuable petrochemical feedstock and the development of technologies for their production, such as fluid catalytic cracking. The most popular petrochemical products are lower olefins, such as propylene, butylene. Every year, 400 million tons of olefins is produced from different technological ways. About 60 % of the world's crude oil is used in fluid catalytic cracking, with application of this technology 59 % of all olefins is produced globally. In accordance with the analysis of the current state of the oil refining and petrochemical industry, in order to increase the yield of olefins, it is indispensable deeply analyze fluid catalytic cracking process and reactions. The establishment of thermodynamic laws is the first step in the analysis of a chemical process. The main aim of the research is to determine the influence of the structure of hydrocarbon isomers on thermodynamic parameters and probability of reactions with the aim of formation of unsaturated gaseous cracking products. Methods: mathematical calculations based on the methods of functional groups including Constantinou–Gani and Joback and the quantum chemistry method done to analyze thermodynamic parameters such as enthalpy and Gibbs free energy of catalytic cracking reactions at various temperatures; assessment of the effectiveness of the methods was done based on the comparison of the mathematical calculation results with literature data. Results. It was percieved that the influence of the structure of isomers on the thermodynamic laws of reactions is much more significant than the change of temperature of fluid catalytic cracking process. As a result of thermodynamic analysis, it was concluded that cracking such isomers is more preferable to obtain gaseous products: 1) 2,2,3-trimethylbutane for production of propylene; 2) 2-methylhexane, 3-methylhexane and 3-ethylpentane for production of propane and iso-butylene; 3) 1-octene for production of butylene. The above gaseous products are obtained by secondary cracking of hydrocarbons in the gasoline fraction. Thus, it is possible to achieve the maximum process selectivity for olefins by selecting the process conditions (temperature, contact time). It is concluded that the method of functional groups based on Constantinoui–Gani accurately describes the thermodynamic laws of cracking reactions, but at the same time does not consider the transformation of non-aromatic compounds and the effect of variations cis- and trans-configurations in the molecular structure. Thus, in these cases it is recommended to use quantum chemistry methods.

One of the major limiting factors to nuclear reactors lifetime is the radiation-induced material damage in the reactor vessel (RV). In this study, the MCNP cross-sectional library (ENDF/B-VI) was modified to evaluate and analyze the radiation damage on the aluminum vessel of the MNSR research reactor. The neutron fluence, displacements per atom (DPA), gas production rate (He and H), heating rate and silicon production were calculated in the aluminum vessel. The result showed after 5000 h of operating time, the maximum integrated fluences on the vessel surface were 4.79 × 1017 and 5.83 × 1016 n.cm−2 in the thermal and fast regions, respectively. The total damage, gas production (H and He), heating rate and silicon production were 3.14 × 10−04 dpa, 8.46 × 10−04 appm and 1.20 × 10−04 appm, 1.20 × 10−04 J/g and 1.20 × 10−04 g−1, respectively. The contribution of the fast neutrons in the radiation damage, gas production (H and He) and heating rate was most effective. The radiation damage on the reactor vessel is less than the limits, and the reactor operation can be continued. [ABSTRACT FROM AUTHOR]

Abstract Background Salmonella and Shigella are major enteric pathogens that cause diarrhea in children worldwide. They are pathogenic microbes that cause significant diarrheal morbidity and mortality in under five children in resource limited countries. Thus, this systemic review and meta-analysis aimed to investigate the prevalence of Salmonella and Shigella species and their multidrug resistance patterns in pediatric populations in Ethiopia. Methods The articles were searched extensively in the electronic databases and grey literature using entry terms or phrases. Studies meeting the eligibility criteria were extracted in MS Excel and exported for statistical analysis into STATA version 14 software. The overall pooled prevalence of Salmonella and Shigella species was computed using a random-effects model. Heterogeneity was assessed using the Cochrane Q test and I2 statistics with corresponding p-values. Publication bias was assessed using a funnel plot and Egger’s test. In addition, sensitivity analysis was performed to determine the impact of individual studies on the pooled effect size. Result Of a total of 742 identified studies, 89 studies were eligible for full-text analysis. Of 89 studies, 21 were included for meta-analysis involving 5318 study participants. These eligible studies reported a total of 593 bacterial isolates. The overall pooled prevalence of Salmonella and Shigella among pediatrics in Ethiopia was 10.70% (95% CI: 8.96–12.45), with substantial heterogeneity (I2 = 82.1%, p

ABSTRACT Background and Aim Leprosy is one of the most common skin neglected tropical diseases in Ethiopia posing social stigma, physical disability, deformity, discrimination, loss of social status, and poor quality of life in families. Hence, evidence‐based collaborative inter‐sectoral actions should be performed to reduce and eliminate its burden in endemic areas. Thus, the aim of this study was to assess the acid‐fast positivity rate and associated factors of leprosy among suspected cases in Northeastern Ethiopia: a cross‐sectional study. Method A cross‐sectional study was conducted from September 2022 to March 2023 among 256 leprosy‐suspected cases selected using a simple random sampling technique. A semi‐structured questionnaire was used to collect socio‐demographic, clinical, and predictor variables of leprosy through face‐to‐face interviews. Skin slit specimens were collected and stained using Ziehl–Neelsen staining technique. STATA 17 was used for analysis. The scale reliability coefficient was checked using Cronbach's α and the goodness‐of‐fit test of the model was assessed by the Hosmer–Lemshow test. Moreover, bivariable and multivariable logistic regression were computed. Finally, variables with an adjusted odds ratio and their p

Background: Changing patterns in community respiratory virus activity were reported in different geographical locations during the COVID-19 pandemic. In this study, we aimed to assess the prevalence of circulating respiratory viruses, including SARS-CoV-2, during the season 2021–2022 in Tunisia. Methods: We retrospectively enrolled 328 nasopharyngeal samples received at the Triage Center of Habib Bourguiba Hospital from patients with acute respiratory symptoms during September 2021–May 2022. All samples were screened for both SARS-CoV-2 and common respiratory viruses. This latter detection was performed using end-point multiplex RT-PCRs, Real-Time PCR, and AllplexTM Respiratory Panel 1 kit (Seegene) for Influenza Virus A (IFVA) and Respiratory Syncytial Virus (RSV) subtyping. Results: Among included patients, at least one viral pathogen was identified in 118 (35.9 %) patients. The detection rate of SARS-CoV-2 was 21.6 %. A low viral coinfection rate was observed (3.3 %). The most prevalent pathogen among non-SARS-CoV-2 viruses was Enterovirus/Rhinovirus (HEV/HRV) (59.6 %) followed by IFVA (15.3 %) and Adenoviruses (ADV) (11.5 %). Only IFVA H3N2 was found to circulate during the study period. A negative virus interaction was eventually induced by SARS-CoV-2, as it was shown by lower levels of activity of non-SARS-CoV-2 viruses (not exceeding 17.7 %) while infections due to pandemic Omicron variants of concern became widespread. Conclusions: This study highlights the relative return of community IFVA circulation during the 2021–2022 season in Tunisia. A negative viral interaction between SARS-CoV-2 and other respiratory viruses is highly suggested, which explains, in addition to the easing of COVID-19 restriction measures, the epidemiological changes in non-SARS-CoV-2 viruses circulation.

Abstract Background Anxiety symptoms in older adults can significantly impact their well-being. Physical activity is increasingly recognized as a potential intervention to alleviate anxiety in this population. We conducted a systematic review and meta-analysis to explore the impact of physical activity on anxiety symptoms in geriatric individuals. Methods A systematic search was conducted in MEDLINE (via PubMed), Scopus, and Embase databases until November 29, 2023. Two independent reviewers screened articles based on predefined inclusion criteria. Results Eleven randomized controlled trials were included. These trials, involving 770 geriatric participants, demonstrated a significant overall effect of physical activity on reducing anxiety symptoms (SMD =-0.60, 95% CI: -0.88 to -0.32). Subgroup analysis based on type of intervention and duration of follow-up was performed. The results showed all types of exercises reduced anxiety symptoms compared to the control group. Furthermore, those studies with shorter follow-up (less than 10 weeks) did not show a statistically significant reduction in anxiety symptoms. Moderate heterogeneity was observed (I2 = 67%). Sensitivity analyses confirmed the robustness of the overall effect size. Funnel plot inspection and Egger’s test (p = 0.36) suggested no signs of publication bias or small study effects. Conclusion This meta-analysis provides strong evidence that physical activity significantly reduces anxiety symptoms in older adults. The study highlights the differential effects of cardio and strength exercises and underscores the high quality of evidence supporting the anxiolytic benefits of physical activity in geriatric populations.

Abstract Background Preeclampsia (PE), an obstetric disorder, remains one of the leading causes of maternal and infant mortality worldwide. In individuals with PE, the coagulation-fibrinolytic system is believed to be among the most significantly impacted systems due to maternal inflammatory responses and immune dysfunction. Therefore, this systematic review and meta-analysis aimed to assess the association of prothrombin time (PT), thrombin time (TT) and activated partial thromboplastin time (APTT) levels with preeclampsia. Methods This systematic review and meta-analysis was conducted in accordance with the PRISMA guidelines. Articles relevant to the study, published from July 26, 2013, to July 26, 2023, were systematically searched across various databases including PubMed, Scopus, Embase, and Hinari. The methodological quality of the articles was evaluated using the Joanna Briggs Institute critical appraisal checklist. Utilizing Stata version 14.0, a random-effects model was employed to estimate the pooled standardized mean difference (SMD) along with the respective 95% CIs. The I2 statistics and Cochrane Q test were utilized to assess heterogeneity, while subgroup analyses were performed to explore its sources. Furthermore, Egger’s regression test and funnel plot were employed to assess publication bias among the included studies. Results A total of 30 articles, involving 5,964 individuals (2,883 with PE and 3,081 as normotensive pregnant mothers), were included in this study. The overall pooled SMD for PT, APTT, and TT between PE and normotensive pregnant mothers were 0.97 (95% CI: 0.65–1.29, p

Abstract A library of novel bis-Schiff base derivatives based on thiobarbituric acid has been effectively synthesized by multi-step reactions as part of our ongoing pursuit of novel anti-diabetic agents. All these derivatives were subjected to in vitro α-glucosidase inhibitory potential testing after structural confirmation by modern spectroscopic techniques. Among them, compound 8 (IC50 = 0.10 ± 0.05 µM), and 9 (IC50 = 0.13 ± 0.03 µM) exhibited promising inhibitory activity better than the standard drug acarbose (IC50 = 0.27 ± 0.04 µM). Similarly, derivatives (5, 6, 7, 10 and 4) showed significant to good inhibitory activity in the range of IC50 values from 0.32 ± 0.03 to 0.52 ± 0.02 µM. These derivatives were docked with the target protein to elucidate their binding affinities and key interactions, providing additional insights into their inhibitory mechanisms. The chemical nature of these compounds were reveal by performing the density functional theory (DFT) calculation using hybrid B3LYP functional with 6-311++G(d,p) basis set. The presence of intramolecular H-bonding was explored by DFT-d3 and reduced density gradient (RGD) analysis. Furthermore, various reactivity parameters were explored by performing TD-DFT at CAM-B3LYP/6-311++G(d,p) method.

This comprehensive review provides an in-depth exploration of the intriguing phenomenon of parental coprophagy in wild birds and its profound implications on the influence of adult avian parents’ health. This review investigates the composition and dynamics of avian feces’ microbiota, casting light on the various dietary, environmental, and genetic factors that influence its diversity. Furthermore, it emphasizes parental coprophagy, a behavior observed in numerous bird species, particularly among herbivorous and passerine birds. The review investigates multiple hypotheses proposed to explain the occurrence of coprophagy. It delves into its function as a potential mechanism for transmitting microorganisms, particularly feces bacteria, from nestlings to their parents. This microbial transfer may affect the health and well-being of adult avian parents. In addition, the review highlights the current research deficits and debates surrounding coprophagy. These gaps include crucial aspects such as the onset of coprophagy, its long-term effects on both parents and offspring, the nutritional implications of consuming nestling feces, the potential risks of pathogen transmission, and the ecological and evolutionary factors that drive this behavior. As the review synthesizes existing knowledge and identifies areas requiring additional research, it emphasizes the significance of future studies that comprehensively address these gaps. By doing so, we can understand coprophagy’s ecological and evolutionary significance in wild birds, advancing our knowledge on avian biology. This information can improve conservation efforts to protect migratory bird populations and their complex ecosystems.

Heart failure is a root cause of morbidity and mortality worldwide. Due to the limited regenerative capacity of the heart following myocardial injury, stem cell-based therapies have been considered a hopeful approach for improving cardiac regeneration. In recent years, different kinds of cell products have been investigated regarding their potential to treat patients with heart failure. Despite special attention to cell therapy and its products, therapeutic efficacy has been disappointing, and clinical application is not affordable. In the past few years, a subset of small extracellular vehicles (EVs), commonly known as “exosomes,” was reported to grant regenerative and cardioprotective signals at a value similar to their donor cells. The conceptual advantage is that they may be ideally used without evoking a relevant recipient immune response or other adverse effects associated with viable cells. The evidence related to their beneficial effects in animal models of heart failure is rapidly growing. However, there is remarkable heterogeneity regarding source cells, isolation process, effective dosage, and delivery mode. This brief review will focus on the latest research and debates on regenerative potential and cardiac repair of exosomes from different sources, such as cardiac/non-cardiac stem, somatic cells, and progenitor cells.Overall, the current state of research on exosomes as an experimental therapy for heart diseases will be discussed.

During the 2022-outbreak, peculiar clinical presentations of Mpox have been described, some of which can make the diagnosis of the disease extremely challenging. Here we report a case series of fourteen patients with Mpox pharynogotonsillar involvement (PTI) seen at National Institute for Infectious Diseases, “Lazzaro Spallanzani”, in Rome, Italy from May to September 2022. All included patients were men who have sex with men (median age 38 years) reporting unprotected sex within three weeks from symptoms onset. Seven out of fourteen patients needed hospitalization due to uncontrolled pain, reduced airspace and difficulty swallowing, of whom five were effectively treated with tecovirimat or cidofovir. The remaining two patients were treated with symptomatic drugs. The typical Mpox muco-cutaneous manifestations were not observed simultaneously with PTI in three patients, two of whom developed the lesions after several days, while one never manifested them. Polymerase Chain Reaction (PCR) for Mpox virus was positive in oropharyngeal swab, saliva and serum. Although PTI occurs in only a small percentage of Mpox cases, its diagnosis is of utmost importance. In fact, this localization, if not identified, could lead to serious complications in the absence of early antiviral treatment and to missed diagnosis with an increased risk of disease transmission.

Abstract Background Shigella spp., which are facultative anaerobic bacilli within the Enterobacteriaceae family, present a significant public health burden due to their role as prominent contributors to diarrheal diseases worldwide. A molecular analysis can facilitate the identification and assessment of outbreaks involving this bacterium. So, we aimed to investigate the antibiotic susceptibility pattern and clonal relatedness of clinical Shigella spp. isolates obtained from patients with diarrhea in Hormozgan province, South of Iran. Methods From 2019 to 2021, a cross-sectional investigation was conducted on 448 stool samples obtained from patients who were experiencing diarrhea, in the southern region of Iran. Shigella spp. isolates were identified based on biochemical and serological tests. All Shigella species were verified using species-specific polymerase chain reaction (PCR), followed by susceptibility testing to antimicrobial agents. Subsequently, genotyping of all Shigella species was conducted using ERIC-PCR. Results Out of a total of 448 stool samples, the presence of Shigella was detected in 62 cases, accounting for a prevalence rate of 13.84%. Among the identified isolates, the majority were attributed to S. flexneri, representing 53.23% of the cases. This was followed by S. sonnei at 24.19% and S. boydii at 22.58%. Notably, no instances of S. dysenteriae were found. The highest prevalence of Shigella isolates was observed in infants and children under the age of five. A significant proportion of the identified isolates demonstrated resistance to various antibiotics. Specifically, high resistance rates were noted for ampicillin (90.78%), piperacillin–tazobactam (87.1%), cefixime (83.87%), trimethoprim–sulfamethoxazole (83.87%), cefotaxime (82.26%), and ceftriaxone (80.65%). In addition, a substantial number (87.1%) of the isolates exhibited a multidrug-resistant (MDR) phenotype. Using the ERIC-PCR method, a total of 11 clusters and 6 distinct single types were identified among all the Shigella isolates. Conclusion A notable occurrence of antibiotic-resistant Shigella species has been noted, with multi-drug resistant (MDR) strains presenting an increasing challenge for treating shigellosis worldwide, and this includes Iran. Techniques such as ERIC-PCR are useful for assessing the genetic variation and connections between Shigella strains, which indirectly contributes to understanding antimicrobial resistance patterns. Further research is needed to explore the specific correlation between resistance genes and ERIC genotyping patterns in Shigella strains.

Multiple sclerosis (MS) is a chronic autoimmune disease with an unknown etiology. The purpose of this research was to assess miR-223, miR-146a, and miR-193a in acute and chronic phases of experimental autoimmune encephalomyelitis (EAE) mice to consider the possible role of these genes in the pathogenesis of MS. EAE induction was given by myelin oligodendrocyte glycoprotein peptide on female C57BL/6 mice. Clinical scores and other criteria were followed daily until day 21 for the acute group and day 77 for the chronic group. At the end of the course, inflammation and demyelination of the central nervous system (CNS) were assessed by histological analysis. MicroRNA expression levels were assessed by real-time PCR. EAE development attenuated in the chronic group, and histological analysis showed less infiltration and demyelination in the chronic group compared to the acute group. The upper expression of miR-223 is demonstrated in the acute phase of EAE. Moreover, the expression levels of miR-146a and miR-193a decreased in the chronic phase of EAE. MiR-223 showed a highly coordinated elevation in the acute phase both in vivo and in vitro. MiR-146a shares a pathway with miR-223 through effecting IL-6 expression. Further studies are needed to reveal their impact on EAE and possible applications as drug targets and biomarkers.