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In a lot of engineering applications, one has to recover the temperature of a heat body having a surface that cannot be measured directly. This raises an inverse problem of determining the temperature on the surface of a body using interior measurements, which is called the sideways problem. Many papers investigated the problem (with or without fractional derivatives) by using the Cauchy data u(x0,t),ux(x0,t)$$ u\left({x}_0,t\right),{u}_x\left({x}_0,t\right) $$ measured at one interior point x=x0∈(0,L)$$ x={x}_0\in \left(0,L\right) $$ or using an interior data u(x0,t)$$ u\left({x}_0,t\right) $$ and the assumption limx→∞u(x,t)=0$$ {\lim}_{x\to \infty }u\left(x,t\right)=0 $$. However, the flux ux(x0,t)$$ {u}_x\left({x}_0,t\right) $$ is not easy to measure, and the temperature assumption at infinity is inappropriate for a bounded body. Hence, in the present paper, we consider a fractional sideways problem, in which the interior measurements at two interior point, namely, x=1$$ x=1 $$ and x=2$$ x=2 $$, are given by continuous data with deterministic noises and by discrete data contaminated with random noises. We show that the problem is severely ill‐posed and further constructs an a posteriori optimal truncation regularization method for the deterministic data, and we also construct a nonparametric regularization for the discrete random data. Numerical examples show that the proposed method works well. [ABSTRACT FROM AUTHOR]

This paper presents a two‐stage deep learning framework, RR‐HCL‐SVM, designed to aid in the assessment of residual thyroid tissues following thyroidectomy, utilizing single‐photon emission computed tomography (SPECT) images. Leveraging the power of deep learning, our model offers a comprehensive solution for the detection and assessment of remaining thyroid tissues. To enhance accuracy, we introduce a unique combination of features, incorporating the Radio Scan Index (RSI) and radiomics features. These features not only improve accuracy but also provide valuable insights into tissue characterization. Moreover, we employ efficient clustering techniques for feature dimension reduction, preserving model performance while reducing computational complexity. Experimental results demonstrate the effectiveness of our approach, achieving an impressive F1 score of 0.97, sensitivity of 0.96, and specificity of 0.98. The RR‐HCL SVM framework holds great promise in the clinical setting for the precise evaluation of residual thyroid tissues post‐thyroidectomy, offering potential benefits for patient care and treatment planning. [ABSTRACT FROM AUTHOR]

The Finite Element Method (FEM) is a widely applied method for design calculations in many industries, including civil engineering, textile technology and aerospace. Computational simulation is subject to many uncertain parameters that greatly affect the results of structural analysis and evaluation. This is especially true for structures made of composite materials and complex structures. Determining the exact computational parameters is difficult because the structure involves many materials and components. Not to mention that for some structures, removing some additional components also affects the calculation results. Therefore, the present research aims to propose a simple and straightforward calculation method that ensures the accuracy of the finite element model based on swarm intelligence, namely the Particle Swarm Optimization (PSO) algorithm. The results reveal a good compromise between the laboratory results and the computational simulations for the model scale studied. In this way, an accurate and reliable model can be produced that can be applied to structural health monitoring, design optimization, or reliability analysis. [ABSTRACT FROM AUTHOR]

Aim: Urinary liver-type fatty acid binding protein (L-FABP) has potential utility as an early prognostic biomarker ahead of traditional severity scores in coronavirus disease 2019 and sepsis, however, the mechanism of elevated urinary L-FABP in the disease has not been clearly elucidated. We investigated the background mechanisms of urinary L-FABP excretion through non-clinical animal model focusing on histone, which is one of the aggravating factors in these infectious diseases. Methods: Male Sprague--Dawley rats were placed in central intravenous catheters, and these rats were given a continuous intravenous infusion of 0.25 or 0.5 mg/kg/ min calf thymus histones for 240 min from caudal vena cava. Results: After the administration of histone, urinary L-FABP and gene expression of an oxidative stress marker in the kidney increased in a histone dose-dependent manner before increased serum creatinine. Upon further investigation, fibrin deposition in the glomerulus was observed and it tended to be remarkable in the high dose administrated groups. The levels of coagulation factor were significantly changed after the administration of histone, and these were significantly correlated with the levels of urinary L-FABP. Conclusions: Firstly, it was suggested that histone is one of the causative agents for the urinary L-FABP increase at an early stage of the disease with a risk of acute kidney injury. Secondly, urinary L-FABP could be a marker reflecting the changes of coagulation system and microthrombus caused by histone in the early stage of acute kidney injury before becoming severely ill and maybe a guide to early treatment initiation. [ABSTRACT FROM AUTHOR]

Colistin is a critically important antimicrobial for human medicine, and colistin‐resistant Escherichia coli are commonly found in poultry and poultry products in Southeast Asia. Here, we aim at disentangling the within‐farm and outside‐farm drivers of colistin resistance in small‐scale chicken farms of the Mekong delta of Vietnam. Nineteen Vietnamese chicken farms were followed up along a whole production cycle, during which weekly antimicrobial use data were recorded. At the beginning, middle and end of each production cycle, commensal E. coli samples from birds were collected, pooled and tested for colistin resistance. Twelve models were fitted to the data using an expectation–maximization algorithm and compared. We further tested the spatial clustering of the occurrence of resistance importations from external sources using the local Moran's I statistic. In the best model, colistin resistance in E. coli from chickens was found to be mostly affected by importations of resistance, and, to a lesser extent, by the use of antimicrobials in the last 1.73 weeks [0.00; 2.90], but not by the use of antimicrobials in day‐olds, nor their colistin resistance carriage from hatchery. The occurrence of external source importations proved to be sometimes spatially clustered, suggesting a role of local environmental sources of colistin resistance. [ABSTRACT FROM AUTHOR]

Distichochlamys citrea, an endemic plant species found only in Vietnam, traditionally known effective for internal inflammation and infection, thus considered as a promising natural antibiotic source. A variety of experimental‐computational methodologies were utilised. Gas chromatography‐mass spectrometry reveals twenty‐one bioactive components (C1‐C21) is found in the n‐hexan extract. Bioassays indicate its total antibiotic activity of high significance against Streptococcus pyogenes (IZD 14±2.0 mm; MIC value of 156.25 μg.mL−1). Docking simulation predicts C17 (DS −12.9 kcal.mol−1; RMSD 1.34 Å)>C14 (DS −12.3 kcal.mol−1; RMSD 1.58 Å)>C16 (DS −12.0 kcal.mol−1; RMSD 1.30 Å) as the most effective inhibitors towards S‐ribosylhomocysteine lyase structure (UniProtKB: P0C0C7). Quantitative structure‐activity relationships suggest all the compounds are predicted with high biocompatibility in reference for oral drug development, and specifiy C1‐C21 especially safe for use in vertebrates. The results preliminarily confirm the significant antibiotic activity of Distichochlamys citrea and encourage further in‐depth experiments in order to harness its pharmacological potentiality. [ABSTRACT FROM AUTHOR]

Copper lighter tetrylenes are promising for inhibition towards Rhizoctonia solani-based protein PDB-4G9M and Magnaporthe oryzae-based PDB-6JBR in rice. Quantum properties of four hypothetic copper complexes of carbenes and silylenes (Cu-NHC1, Cu-NHC2, Cu-NHSi1, and Cu-NHSi2) were examined using the density functional theory. Their inhibitability towards the targeted proteins was evaluated using molecular docking simulation. Quantum analysis predicts the stability of the investigated complexes and thus their practical existability and practicable synthesisability. Their electronic configurations are justified as highly conducive to intermolecular interaction. Regarding ligand-protein as carbenes/silylenes-4G9M inhibitory structures, the stability is estimated in the order [Cu-NHC2]-4G9M (DS −12.9 kcal⋅mol−1) > [Cu-NHSi1]-4G9M (DS −11.8 kcal⋅mol−1) = [Cu-NHSi2]-4G9M (DS −11.7 kcal⋅mol−1) > [Cu-NHC1]-4G9M (DS –11.4 kcal⋅mol−1). In contrast, the corresponding order for the carbenes/silylenes-6JBR systems is [Cu-NHSi2]-6JBR (DS –13.4 kcal⋅mol−1) > [Cu-NHC2]-6JBR (DS −13.0 kcal⋅mol−1) = [Cu-NHSi1]-6JBR (DS −12.6 kcal⋅mol−1) > [Cu-NHC1]-6JBR (DS −12.3 kcal⋅mol−1). In theory, this study suggests a potentiality of copper lighter tetrylenes and their derivatives against the infection of fungi Rhizoctonia solani and Magnaporthe oryzae, thus encouraging attempts for experimental developments. [ABSTRACT FROM AUTHOR]

Streptococcus suis infections are an emerging zoonotic agent causing severe disease in humans and a major pig pathogen worldwide. We investigated the colonization of S. suis in healthy chickens in different flocks (n = 59) as well as in‐contact pigs in farms with S. suis‐positive chickens (n = 44) in the Mekong Delta of Vietnam. Streptococcus suis was isolated from 20 (33.9%) chicken flocks and from all pigs investigated. Chicken isolates formed a distinct genotypic cluster compared with pig and human strains, although two chicken isolates (10%) clustered with pig isolates. Chicken isolates had unusually high levels of resistance against tetracycline (100%), clindamycin (100%) and erythromycin (95%); and intermediate resistance against penicillin (35%) and ceftriaxone (15%). Our findings suggest that chickens may potentially represent a source of S. suis infection to in‐contact humans and pigs. [ABSTRACT FROM AUTHOR]

GC‐MS was applied to identify 24 main substances in Melaleuca cajuputi essential oil (TA) extracted from fresh cajeput leaves through steam distilling. The inhibitory capability of active compounds in the TA from Thua Thien Hue, Vietnam over the Angiotensin‐Converting Enzyme 2 (ACE2) protein in human body ‐ the host receptor for SARS‐CoV‐2 and the main protease (PDB6LU7) of the SARS‐CoV‐2 using docking simulation has been studied herein. The results indicate that the ACE2 and PDB6LU7 proteins were strongly inhibited by 10 out of 24 compounds accounting for 70.9% in the TA. The most powerful anticoronavirus activity is expressed in the order: Terpineol (TA2) ≈ Guaiol (TA5) ≈ Linalool (TA19) > Cineol (TA1) > β‐Selinenol (TA3) > α‐Eudesmol (TA4) > γ‐Eudesmol (TA7). Interestingly, the synergistic interactions of these 10 substances of the TA exhibit excellent inhibition into the ACE2 and PDB6LU7 proteins. The docking results orient that the natural Melaleuca cajuputi essential oil is considered as a valuable resource for preventing SARS‐CoV‐2 invasion into human body. [ABSTRACT FROM AUTHOR]

In a lot of engineering applications, one has to recover the temperature of a heat body having a surface that cannot be measured directly. This raises an inverse problem of determining the temperature on the surface of a body using interior measurements, which is called the sideways problem. Many papers investigated the problem (with or without fractional derivatives) by using the Cauchy data u(x0,t),ux(x0,t) measured at one interior point x=x0∈(0,L) or using an interior data u(x0,t) and the assumption limx→∞u(x,t)=0. However, the flux ux(x0,t) is not easy to measure, and the temperature assumption at infinity is inappropriate for a bounded body. Hence, in the present paper, we consider a fractional sideways problem, in which the interior measurements at two interior point, namely, x=1 and x=2, are given by continuous data with deterministic noises and by discrete data contaminated with random noises. We show that the problem is severely ill‐posed and further construct an a posteriori optimal truncation regularization method for the deterministic data, and we also construct a nonparametric regularization for the discrete random data. Numerical examples show that the proposed method works well. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study was to improve the penetration during in vitro fertilization (IVF) of a frozen lot of epididymal sperm with a notoriously low fertilization ability of a Ban boar which is a native Vietnamese breed by optimizing different parameters of the IVF system. In Experiment 1, we determined that Pig‐fertilization medium was superior medium to Tyrode's albumin lactate pyruvate‐polyvinyl alcohol medium for IVF and defined the optimum the sperm concentration (1 × 106 sperm/ml). In Experiment 2, we clarified that partial removal of cumulus cells from cumulus‐oocyte complexes by hyaluronidase treatment before IVF enhances sperm penetration, whereas complete cumulus removal reduces penetration. Finally, in Experiment 3 the elevation of concentration of caffeine in Pig‐fertilization medium from 2 to 5 mmol/L and the prolongation of the co‐culture of gametes from 3 to 5 hr significantly increased the total penetration rate from 15.2% to over 50%. In conclusion, the combination of partial oocyte denudation, an elevated caffeine concentration in Pig‐fertilization medium and an extended interval of IVF with using an optimized sperm concentration was a potent way to improve the fertilization results for a frozen epididymal Ban sperm lot with low fertility. [ABSTRACT FROM AUTHOR]

A new rhodamine-ethylenediamine-nitrothiourea conjugate (RT) was synthesized and its sensing property as a fluorescent chemodosimeter toward metal ions was explored in water media. Analytical results from absorption and fluorescence spectra revealed that the addition of Hg2+ ions to the aqueous solution of the chemodosimeter RT caused a distinct fluorescence OFF-ON response with a remarkable visual color change from colorless to pink; however, no clear spectral and color changes were observed from other metal ions including: Zn2+, Cu2+, Cd2+, Pb2+, Ag+, Fe2+, Cr3+, Co3+, Ni2+, Ca2+, Mg2+, K+ and Na+. The sensing results and the molecular structure suggested that a Hg2+-induced a desulfurization reaction and cyclic guanylation of the thiourea moiety followed by ring-opening of the rhodamine spirolactam in RT are responsible for a distinct fluorescence turn-on signal, indicating that RT is a remarkably sensitive and selective chemodosimeter for Hg2+ ions in aqueous solution. Hg2+ within a concentration range from 0.1 to 25 μM can be determined using RT as a chemodosimeter and a detection limit of 0.04 μM is achieved. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]