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STREAM, developed by the Computational Reactor Physics and Experiment laboratory (CORE) of the Ulsan National Institute of Science and Technology (UNIST), is a deterministic neutron- and photon-transport code primarily designed for light water reactor (LWR) analysis. Initially, the photon module in STREAM did not account for fluorescence and bremsstrahlung photons. This article presents recent developments regarding the integration of atomic relaxation and bremsstrahlung models into the existing photon module, thus allowing for the transport of secondary photons. The photon flux and photon heating computed with the newly incorporated models is compared to results obtained with the Monte Carlo code MCS. The incorporation of secondary photons has substantially improved the accuracy of photon flux calculations, particularly in scenarios involving strong gamma emitters. However, it is essential to note that despite the consideration of secondary photon sources, there is no noticeable improvement in the photon heating for LWR problems when compared to the photon heating obtained with the previous version of STREAM.

Myocardial infarction (MI) commonly known as "heart attack" results from the blockage of blood flow to the heart. Postmenopausal women face an elevated risk of MI due to declining estrogen levels, a hormone pivotal in maintaining cardiovascular health. It promotes vasodilation, reduces inflammation, and improves lipid profiles. While estrogen therapy shows promise in mitigating MI risk for postmenopausal women, its efficacy in prevention and recovery remains a subject of debate. This review provides a critical assessment of existing evidence on estrogen therapy's cardioprotective effects for postmenopausal women. It delves into estrogen's role in vascular function enhancement, inflammation reduction, and lipid metabolism modulation. Additionally, it addresses the various forms of estrogen therapy, administration methods, dosage considerations, safety implications, and associated risks. The review highlights the existing controversies and knowledge gaps related to estrogen therapy for MI prevention. It underscores the urgency for in-depth research to decipher the nexus between estrogen therapy and MI risk, especially concerning primary prevention and specific postmenopausal subgroups. Future studies should investigate optimal formulations, doses, and administration routes of estrogen therapy as well as assess treatment timing and duration. Comparative studies and long-term follow-up are necessary to inform clinical decision-making and improve patient care. Addressing these research gaps will empower clinicians to make more judicious choices about estrogen therapy for MI prevention and recovery in postmenopausal women, aiming for enhanced patient outcomes.

IntroductionPrimary open-angle glaucoma (POAG) is a characteristic optic neuropathy, caused by degeneration of the optic nerve-forming neurons, the retinal ganglion cells (RGCs). High intraocular pressure (IOP) and aging have been identified as major risk factors; yet the POAG pathophysiology is not fully understood. Since RGCs have high energy requirements, mitochondrial dysfunction may put the survivability of RGCs at risk. We explored in buffy coat DNA whether mtDNA variants and their distribution throughout the mtDNA could be risk factors for POAG.MethodsThe mtDNA was sequenced from age- and sex-matched study groups, being high tension glaucoma (HTG, n=71), normal tension glaucoma patients (NTG, n=33), ocular hypertensive subjects (OH, n=7), and cataract controls (without glaucoma; n=30), all without remarkable comorbidities.ResultsNo association was found between the number of mtDNA variants in genes encoding proteins, tRNAs, rRNAs, and in non-coding regions in the different study groups. Next, variants that controls shared with the other groups were discarded. A significantly higher number of exclusive variants was observed in the D-loop region for the HTG group (~1.23 variants/subject), in contrast to controls (~0.35 variants/subject). In the D-loop, specifically in the 7S DNA sub-region within the Hypervariable region 1 (HV1), we found that 42% of the HTG and 27% of the NTG subjects presented variants, while this was only 14% for the controls and OH subjects. As we have previously reported a reduction in mtDNA copy number in HTG, we analysed if specific D-loop variants could explain this. While the majority of glaucoma patients with the exclusive D-loop variants m.72T>C, m.16163 A>G, m.16186C>T, m.16298T>C, and m.16390G>A presented a mtDNA copy number below controls median, no significant association between these variants and low copy number was found and their possible negative role in mtDNA replication remains uncertain. Approximately 38% of the HTG patients with reduced copy number did not carry any exclusive D-loop or other mtDNA variants, which indicates that variants in nuclear-encoded mitochondrial genes, environmental factors, or aging might be involved in those cases.ConclusionIn conclusion, we found that variants in the D-loop region may be a risk factor in a subgroup of POAG, possibly by affecting mtDNA replication.

One of the primary causes of premature pavement deterioration in Asphalt Concrete (AC) mixtures is the breaking of the adhesive bond between the aggregate and the binder. The purpose of this study is to assess the performance characteristics of AC mixture utilizing the Rediset LQ-1200 additive. In order to achieve this goal, tests such as the Marshall Stability (MS), Marshall Stability Ratio (MSR), Indirect Tensile (IDT), indirect tensile cracking, and Wheel Tracking (WT) were deployed to evaluate the mechanical properties of AC mixtures. The findings demonstrated a considerable improvement in the physical parameters of the AC mixture with the Rediset LQ-1200 additive compared to the base AC mixture. The MS and MSR were improved by about 28% and 13%, respectively, while the AC mixture's resistance to rutting and cracking was efficiently increased. [ABSTRACT FROM AUTHOR]

Background: The use of antibiotics in children is influenced by the knowledge, attitudes, and behaviors of caregivers, especially mothers. Objective: This study aimed to assess the knowledge, attitudes, and practices regarding antibiotic use for children among mothers with children under 5 years old in rural areas of northern Vietnam. Methods: This research utilized a cross-sectional descriptive design with a self-administered questionnaire targeting mothers with children under 5 years old in two communes in Hai Duong province and two communes in Hung Yen province. Data collection was conducted from March to April 2023. Chi-square tests and multivariable regression analyses were employed to explore the relationship between the demographic characteristics of mothers and their knowledge, attitudes, and antibiotic use behaviors. Results: The majority of mothers exhibited inadequate knowledge (86.2%), inappropriate attitudes (73.8%), and incorrect antibiotic use behavior (73%). Mothers with university-level education or higher had better knowledge (QR = 4.98; 95% CI: 2.58-9.64) and more correct behaviors (QR = 2.32; 95% CI: 1.31-4.13) in antibiotic use. Mothers with an income higher than 20 million VND exhibited more appropriate attitudes (QR = 5.74; 95% CI: 2.76-11.93) and more correct behaviors (QR = 6.33; 95% CI: 3.18-12.61) regarding antibiotic use. Conclusion: The majority of mothers possess incorrect knowledge, improper attitudes, and irrational antibiotic use behaviors. This calls for continuous interventions and collaborations between healthcare professionals and the community, particularly parents, to enhance the understanding of rational antibiotic use. [ABSTRACT FROM AUTHOR]

Let be a tree, a vertex of degree one is called a leaf. The set of all leaves of is denoted by Leaf(). The subtree − Leaf() of is called the stem of and denoted by Stem(). A tree is called a caterpillar if Stem() is a path. In this paper, we give two sufficient conditions for a connected graph to have a spanning tree whose stem is a caterpillar. We also give some examples to show that these conditions are sharp. [ABSTRACT FROM AUTHOR]

In this research, carbon nanodots decorated TiO2 (CDs/TiO2) were prepared by the microwave method and used as the catalyst for the photo-oxidation of several volatile organic compounds (VOCs), including formaldehyde, acetone, and toluene, in a continuous flow under UV-A radiation. The catalyst was characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), high-resolution transmission electron microscopy (HRTEM), scanning electronic microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), thermogravimetric analysis (TGA), and photoluminescence spectroscopy (PL). The results confirm the vital role of carbon nanodots in the improvement of photocatalytic activity of TiO2 via extending the light absorption into the visible range and lengthening the existence of photoelectrons and holes. The synthetic catalyst exhibited superior photocatalytic performance than the pristine TiO2. The removal rate of formaldehyde, acetone, and toluene in a continuous flow and under humid conditions are 0.38, 0.22, and 0.2 mmol g− 1 h− 1, respectively. While the change in relative humidity had significant impacts on the photocatalytic activity of TiO2, CDs/TiO2 still exhibited a very high and stable VOCs conversion efficiency. Moreover, the photo-oxidation efficiency of formaldehyde on the CDs/TiO2 photocatalyst was maintained the same after 8 cycles. Highlights: Carbon nanodots were successfully prepared by a simple microwave-assisted method. Carbon nanodots played a vital role in the improvement of the photocatalytic activity of TiO2. Photocatalytic removal of formaldehyde, acetone, and toluene was tested under humid conditions. High catalytic stability in the degradation of formaldehyde was obtained on CDs/TiO2. [ABSTRACT FROM AUTHOR]

We consider problem (P) of Kirchhoff-Carrier type with nonlinear terms containing a finite number of unknown values u(η1, t), . . ., u(ηq, t) with 0 ⩽ η1 < η2 < . . . < ηq < 1. By applying the linearization method together with the Faedo-Galerkin method and the weak compact method, we first prove the existence and uniqueness of a local weak solution of problem (P). Next, we consider a specific case (Pq) of (P) in which the nonlinear term contains the sum Sq[u 2 ](t) = q −1 i=1 ∑q u 2 ((i − 1)/q, t). Under suitable conditions, we prove that the solution of (Pq) converges to the solution of the corresponding problem (P∞) as q → ∞ (in a certain sense), here (P∞) is defined by (Pq) in which Sq[u 2 ](t) is replaced by ʃ¹0 u 2 (y, t) dy. The proof is done by using the compactness lemma of Aubin-Lions and the method of continuity with a priori estimates. We end the paper with remarks related to similar problems. [ABSTRACT FROM AUTHOR]

Mangiferin is a xanthonoid found in Mango leaves in abundance with many effects as a hypoglycemic, antioxidant, and anti-inflammatory agent, plant metabolite, and so on. However, nowadays, mango leaves are merely a waste product in Vietnam. To take advantage of this valuable medicinal resource, extraction conditions of mangiferin using classical and ultrasound methods were researched, and mangiferin was purified from Cat Chu mango leaves (Mangifera indica L., Anacardiaceae) collected in Dong Thap. Ultrasound-assisted extraction method was conducted with the following conditions and mangiferin was extracted at a percentage of 6.728% with a purity of 91.11%. Purified mangiferin was evaluated using molecular absorption spectroscopy UV-Vis, scanning electron microscopy (SEM), X-ray diffraction (XRD) spectroscopy, simultaneous thermal analysis (STA: TGA/DSC), and dissolution measurement method. To optimize the solubility and permeability of mangiferin, the solid dispersion system (HPTR) was made by the combination of HPMC 6M:mangiferin at the ratio of 1:5. To investigate the acute, sub-chronic toxicity and hypolipidemia effect of HPTR as compared to purified mangiferin, we followed guidelines for preclinical and clinical trials of Traditional Medicine and Herbal Medicines by the Vietnam Ministry of Health and OECD, and used tyloxapol (Triton WR1339, 400 mg/kg, i.p.) to induce hyperlipidemia. Our results indicated that purified mangiferin and HPTR extract showed no acute toxicity and sub-chronic toxicity and has potential as an antihyperlipidemic agent. The HPTR brought about a significant decrease in total cholesterol, triglycerides and LDL-c when compared to mangiferin, however there was no significance between them. [ABSTRACT FROM AUTHOR]

This study investigated the leaching resistance of alkali activated slag mortars (AAS) under immersion in a 6 M NH4NO3 solution for a duration of up to 28 days, taking into consideration the effect of water-to-binder (w/b) ratio. SEM-EDS analysis revealed decalcification, desodiumization, and dealumination in AASs during leaching, leading to changes in the microstructure and micro-mechanical properties of the materials. A combination of N2-adsorption and MIP analysis demonstrated that there was a coarsening of the structure and an increase in porosity along the depth of degradation in the leached AAS. The predominant pore framework in the leached materials was found to be capillary pores. Furthermore, the elastic modulus and micro-hardness of AAS decreased after 28 days of leaching, as evidenced by micro-indentation. The water permeability of AASs exhibited an exponential rise with the increase in porosity, both before and after leaching, as a consequence of the changes in microstructure. Notably, the w/b ratio significantly influenced the leaching rate, microstructure, and water permeability of the AAS.