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• Twenty Machine Learning (ML) algorithms implemented in Python software to predict fracture load and fracture toughness in three modes. • For fracture load, the algorithms of XGBoost, BRegressor, GBM, ERTRegressor (mode I), XGBoost, GBM, ETRegressor, ERTRegressor (mode II), and BRegressor, GBM, ETRegressor (mixed-mode) had the highest prediction accuracy. • For fracture toughness, the algorithms of BRegressor, ETRegressor, NuSVR, ANNs (mode I), ANNs (mode II), and XGBoost, RDF, BRegressor, ETRegressor, ERTRegressor, ANNs (mixed-mode) had the highest prediction accuracy. • Graphical User Interface (GUI) was developed for fracture prediction. Machine Learning (ML) method is widely used in engineering applications such as fracture mechanics. In this study, twenty different ML algorithms were employed and compared for the prediction of the fracture toughness and fracture load in modes I, II, and mixed-mode (I-II) of various materials, including fibre-reinforced concrete, cement mortar, sandstone, white travertine, marble, and granite. A set of 401 specimens of "Brazilian discs with central cracks" were used as a training and testing dataset. The main features of the experimental technique in each specimen are the fracture mode, the tensile strength of the specimen, the inclination of the crack with loading direction, the thickness of specimens and the half-length of the crack. The improved ML algorithms were implemented using Python programming language. The results of the coefficient of restitution (R2) and statistical metrics confirm that the ML algorithms are able to predict the fracture toughness and fracture load in modes I, II, and mixed-mode (I-II) with high accuracy. To validate the reliability of the proposed ML-based prediction models, three experimental tests were used. Moreover, the Graphical User Interface (GUI) of the ML-based models was created as a practical tool for estimating the fracture load and fracture toughness for engineering problems. [ABSTRACT FROM AUTHOR]

New chloroantimonite glasses were obtained in the SbO - PbCl -AgCl ternary system. Their thermal, optical, and mechanical properties are studied. The concentration of silver chloride increases at the expense of antimony oxide accordingtothe following composition rules: (80- x)SbO -20PbCl - xAgCl and (70- x)SbO -30PbCl - xAgCl. Depending on the AgCl content, Vickers microhardness varied between 110 MPa and 140 MPa. The elastic moduli were measured by ultrasonic velocity. The optical transmission range extended from 400 nm in the visible spectrum to 7 μm in the infrared spectrum. The refractive index was close to 2. The glass transition temperature measured by the DSC ranged from 250 to 290°C. It is shown that the glass transition temperature decreases as AgCl substitutes for SbO and a more stable system was with 20% PbCl in the (80- x)SbO -20PbCl - xAgCl. [ABSTRACT FROM AUTHOR]

This study was aimed to develop simple empirical equations to predict engineering properties of edible sunflower seed (cultivar of GALAMI) and material other grain (MOG) including of hollow seeds and chaff material for designing and setting equipment of cleaning and separation. The properties were evaluated at four levels of moisture content from 30% to 7% (w.b.) (moisture of harvesting to processing). The variation in moisture content showed a statistically significant effect on physical and aerodynamic properties. As the moisture content decreased from 30% to 7% (w.b), length, width, thickness, equivalent diameter, sphericity for seeds (GALAMI), and the projected area, coefficient of static friction, static angle of repose for all materials decreased, whereas the true density and porosity of Seeds (GALAMI) decreased from 561.02 to 457.29kg/m3 and 63.35% to 52.41% respectively, however this value for Chaff materials increased from 822.57 to 897.56 kg/m3 and 89.19% to 90.64% respectively. The coefficient of static friction (μ) was determined for three different surfaces (plywood, rubber and mild steel). The highest difference of value between seeds (GALAMI) with Chaff material and Hollow seeds was in mild steel surface and moisture content of 30%. The value of terminal velocity of all material decreased with decreasing moisture content. The highest average terminal velocity was at moisture content of 30% that for Seeds (GALAMI), Hollow seeds and Chaff material obtained 7.08, 3.62 and 3.39 m/s respectively, and the lowest was at the moisture content of 7% for all material, and reported 5.46, 2.70 and 2.60 m/s respectively. With decrease in moisture content, drag coefficient tended to increase, So that its value for Seeds (GALAMI), Hollow seeds and chaff materials changed from 0.59 to 0.95, 0.80 to 1.42 and 098 to 1.53 respectively. According to this investigation complete theoretical separation of seeds from MOG using air and physical properties of product is possible at various moisture contents. [ABSTRACT FROM AUTHOR]

The physical and aerodynamic characteristics of seeds can strongly influence their movements in the agricultural machine as well as in the air. The knowledge of the physical characteristics of particles is essential for the constructors and operators of agricultural machines. In this research some physical and aerodynamic properties of two Iranian edible seeds of sunflower cultivars (Badami and Doursefid) were studied in the moisture content range from 7% to 30% wet basis (w.b.). With decrease in moisture content the true density of Badami and Doursefid decreased from 561.02 to 457.29 kg/m³ and 509.35 to 440.50 kg/m³, respectively. For studying aerodynamic properties (terminal velocity and drag coefficient) the ratio of mass (g) to projected area (cm²) of seeds were considered as K index. The terminal velocity of both seed decreased with decreasing K index and moisture content. The highest average terminal velocity was at moisture content of 30% for Badami and Doursefid as 7.08 and 6.97 m/s respectively, and the lowest was at the moisture content of 7% for both seed varieties, as 5.46 and 5.39 m/s respectively. With decrease in moisture content, drag coefficient tended to increase, so that its value for Badami and Doursefid changed from 0.59 to 0.95 and 0.52 to 0.75 respectively. [ABSTRACT FROM AUTHOR]

For automotive applications, the mechanical behaviour of the contact area under vibration is one of the key factors for connector reliability. Such vibrations on the bulk contact device are typically in the range of 10-2,000 Hz and result in displacements of only a few microns at the contact interface. In the present study, a bench test has been developed to control motions down to 1 $$\upmu $$m. The objective is to determine the minimum amplitude for fretting-corrosion degradation based on the evolution of contact resistance and to study the effects of the material, the contact force, the coating, for these low displacement amplitudes. To obtain the limit of the appearance of fretting, a sub-micrometer incrementing displacement amplitude methodology was applied on a high stiffness bench test including a double piezoelectric actuator. It was found that the fretting degradation starts to occur from 2 to 6 $$\upmu $$m when the contact force is from 0.5 to 2.5 N with a tin-coated terminal. Moreover, pure copper, tin and nickel have similar amplitude fretting limits while noble metals confirm the absence of fretting up to 10 $$\upmu $$m amplitude and for a large number of operations (10 $$^{6 }$$ cycles). Best fitting of the obtained minimum fretting amplitude data to the Mindlin equation is discussed and improved by a correction factor. [ABSTRACT FROM AUTHOR]

Introduction. End-stage renal disease has been associated with premature atherosclerosis of the cerebral circulation. The risk of stroke, a frequent complication of uremia as a result of cerebral blood flow reduction, is high in dialysis patients. This study aimed to assess brain hemodynamics between hemodialysis interval periods by transcranial Doppler ultrasonography. Materials and Methods. In a case-control study, to evaluate cerebral circulation homodynamics, 20 hemodialysis patients and 20 age- gender-matched healthy control subjects underwent transcranial Doppler ultrasonography. Blood parameters were also measured simultaneously. Among hemodialysis patients, these studies were performed 48 hours after a dialysis session. Results. The mean blood flow velocity (MV) values were significantly higher in the middle cerebral artery (P = .007), anterior cerebral artery (P = .003), posterior cerebral artery-segment 2 (P = .03), basilar artery (P = .05) in hemodialysis patients compared to the controls. The MV had a negative meaningful correlation with hemoglobin and hematocrit in most intracranial arteries of the patients, but no significant correlation was observed between these variables and MV of the arteries in the control group. Conclusions. The MV of the cerebral arteries significantly increases in hemodialysis patients, which could be due to the decrease in hemoglobin levels in these patients. [ABSTRACT FROM AUTHOR]

Abstract: Vitreous systems based on antimony oxide Sb2O3 have been investigated. The influence of MnO substitution on the mechanical and physical properties in the (80− x)Sb2O3–20PbO–xMnO and (70− x)Sb2O3–(30− x)PbO–2xMnO systems has been studied. Vickers hardness, density, molar volume, Young modulus, glass temperature transition, infrared and UV transmission spectra depend on the MnO concentration. Crack analysis of the glass surface under indentor deformation shows the tenacity changes according to concentration of the MnO. [Copyright &y& Elsevier]

Abstract: The mark-tracking method was used in the uniaxial tensile test to determine the elastic properties of optical fibers. The mark-tracking method is based on the follow-up of two markers on the specimen with the help of an image processing technique. It allows us to determine the true strain with respect to the small strains assumption (≤1%) or the finite strains (>1%) without any impact of the rigid solid movement or pulley fiber sliding on the measured strain. Both coated optical fiber and stripped fiber were subjected to the uniaxial tensile test and the cantilever beam bending test. The Young’ modulus results of the stripped fiber were found to be very similar for both tests. Thus, the mark-tracking method is adaptable to the tensile test of optical fibers and the elastic behaviors of both coated optical fiber and stripped fiber are found to be non-linear. Their Young''s moduli are 22 and 79GPa, respectively. These results revealed that those coatings play a mechanical role in fiber elongation. [Copyright &y& Elsevier]

For any informed decision making about community-oriented nursing, it is necessary to map out the community regarding the psychological factors. This study is an attempt to estimate the mental disorders' rate among the age group of 15-65 in the urban areas of Ardabil province. A sample of 1430 individuals was selected through random multistage cluster sampling. The instruments employed in this study included Personal Data Questionnaire and the 28-item General Health Questionnaire (GHQ). The findings revealed that, on the whole, 27.83% of the subjects suffer from different mental disorders. The prevalence rate of mental disorders appeared to vary from 13.3% to 44.4% based on the place of residence, and the highest prevalence rate was found to be social dysfunction and anxiety disorders. According to GHQ test, the prevalence rate of social dysfunction, anxiety, somatization and depression disorders were 32%, 22.30%, 20% and 14%, respectively. The study also showed that the prevalence rate of mental disorders was higher among women as compared with men (34.2% vs. 21.1%). The findings of this study is hoped to contribute to community-oriented nursing practice and education. [ABSTRACT FROM AUTHOR]

Abstract: An experimental method to determine contact radius changes during a spherical instrumented indentation test is proposed in this paper. This method is based on the Hertz theory and only depends on the elastic properties of both the indenter and the sample. The programming of several loading, unloading and reloading cycles has allowed the determination of the unloading stiffness changes and consequently the contact radius changes. Numerical results have shown that the proposed method is sensitive to the piling-up or sinking-in. From the contact radius changes we have proposed a new procedure in order to obtain the real indentation load–depth curve from the measured curve. An experimental study has allowed us to validate our procedure during the beginning of the unloading cycle. [Copyright &y& Elsevier]

The reliability and the expected lifetime of optical links are closely related to the chemical action of the water molecules on silica network. However, polymeric coating also contributes largely to the mechanical properties of the fiber. Dynamic fatigue measurements were performed on silica optical fibers, either bare or coated, using two-point bending bench. Water concentration in test atmosphere was 50% relative humidity or very dry atmosphere. When water content is a few ppm, the dynamic fatigue curve, which expresses the breaking strength as a function of stress rate deviates from linearity at high stress rate. The same behaviour is observed in ambient atmosphere for very high testing speeds. The comparison between bare and coated fibers shows that the fatigue behaviour at high stressing rate is influenced by the polymer coating. [Copyright &y& Elsevier]

A drilling method developed by the authors for the measurement of the hardness profile for surface heat treated steels is based on the proportionality between drilling thrust and material hardness. However, parameters other than hardness related to the material can modify the cutting thrust level. In order to study the influence of the microstructure, the ductility, the toughness and the work hardening of material on the drilling thrust, a few tests were carried out in this work. Tensile and impact tests were carried out on different materials. Moreover, micrographic observations and Vickers micro-hardness were performed on the chips. The study allowed two groups of materials to be distinguished according to the drilling thrust to hardness ratio (R/HV). The first includes not very ductile materials presenting an about constant and low value of R/HV, short, thin and not very work hardened chips. The second includes ductile materials presenting a non constant and high value of R/HV, long, thick and very work hardened chips. As a consequence, the hardness profile determination by drilling method is reliable only if the R/HV ratio is about the same for the treated layer and for the substrate, i.e. if the difference in ductility between the treated layer and the substrate is not very high. [Copyright &y& Elsevier]

Accessible summary The mean duration of untreated psychosis ( DUP) were 261.3 ± 110.8 and 212.5 ± 143.5 days for patients referring to Razi and Fatemi hospital., The DUP mean here was found to be higher as compared with that of the developed countries., Lower education, implausible beliefs and culturally rooted social stigma status of visiting a psychiatrist were found to be playing a role in making DUP longer., Abstract One of the main goals in treatment planning of psychiatric disorders is early diagnosis of patients in the early psychosis period so that duration of untreated psychosis ( DUP) is decreased and the treatment response and outcome is improved. The aim of this study was to investigate the DUP of psychosis and factors affecting it. In this cross-sectional study, 80 patients from the psychiatric clinic of Fatemi hospital in Ardabil and Razi hospital in Tabriz who were in the first episode of psychosis completed a questionnaire. The data were analysed by SPSS statistical software. In this study, the mean DUP measured from the appearance of the first symptoms of psychosis were 261.3 ± 110.8 and 212.5 ± 143.5 days for patients referring to Razi and Fatemi hospital, respectively. About 65% of the patients in Fatemi hospital and 32.5% of them in Razi hospital considered visiting a psychiatrist as hard and very hard. The DUP mean here was found to be higher as compared with that of the developed countries. The following factors were found to be playing a role in making DUP longer: lower education, implausible beliefs and culturally rooted social stigma status of visiting a psychiatrist. [ABSTRACT FROM AUTHOR]

GVHD remains the most significant complication of hematopoietic SCT, despite advances in HLA matching and the identification of risk various factors. To account for the variation in the incidence and severity of this disease, many genetic association studies have been performed in order to explore the role of immunoregulatory gene polymorphisms. These genes include those that encode cytokines, chemokines, and costimulatory molecules. Polymorphisms in other classes of genes such as those involved in drug metabolism, protein folding, and DNA replication have also been studied. In this review, we address the current knowledge of the role of genetic polymorphisms in GVHD. We also discuss the potential pitfalls inherent in genetic association testing and alternative strategies to address these problems. [ABSTRACT FROM AUTHOR]

Abstract: Knowledge of the relationship between the penetration depth and the contact radius is required in order to determine the mechanical properties of a material starting from an instrumented indentation test. The aim of this work is to propose a new penetration depth–contact radius relationship valid for most metals which are deformed plastically by parabolic and spherical indenters. Numerical simulation results of the indentation of an elastic–plastic half-space by a frictionless rigid paraboloïd of revolution show that the contact radius–indentation depth relationship can be represented by a power law, which depends on the reduced Young’s modulus of the contact, on the strain hardening exponent and on the yield stress of the indented material. In order to use the proposed formulation for experimental spherical indentations, adaptation of the model is performed in the case of a rigid spherical indenter. Compared to the previous formulations, the model proposed in the present study for spherical indentation has the advantage of being accurate in the plastic regime for a large range of contact radii and for materials of well-developed yield stress. Lastly, a simple criterion, depending on the material mechanical properties, is proposed in order to know when piling-up appears for the spherical indentation. [Copyright &y& Elsevier]

Sprouting can enhance the bioavailability and stimulate the production of health-promoting compounds. This research explored the potential health benefits of wheat sprouting, focusing on underexplored areas in existing literature such as alterations in phenylalanine ammonia-lyase (PAL) activity and glutathione levels during wheat sprouting. Furthermore, special attention was directed toward asparagine (Asn), the main precursor of acrylamide formation, as regulatory agencies are actively seeking to impose limitations on the presence of acrylamide in baked products. The results demonstrate elevated levels of PAL (4.5-fold at 48 h of sprouting), antioxidants, and total phenolics (1.32 mg gallic acid equivalent/g dry matter at 72 h of sprouting), coupled with a reduction in Asn (i.e. 11-fold at 48 h of sprouting) and glutathione concentrations, after wheat sprouting. These findings suggest that sprouting can unlock health-promoting properties in wheat. Optimizing the sprouting process to harness these benefits, however, may have implications for the techno-functionality of wheat flour in food processing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)