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Previous methods have been developed to predict tracked hydraulic excavator output and associated costs of production, but these fail to provide a “complete” solution to the plant productivity problem. That is, when hiring or purchasing machines plant managers are not normally provided with sufficient detail to optimise the plant selection decision process. The crux of this problem is to choose an appropriate plant item from the vast range available. This paper contributes to resolving this selection process through the application of an optimisation technique, based on linear programming. Specifically, a decision tool for selecting the optimum excavator type for given production scenarios is presented. In achieving this aim, a mass excavation task was specified as the principal decision criterion. Production output and machine hire costs were predicted using both multivariate and bivariate regression models. The decision tool performed well during testing and therefore exhibits significant potential for use by practitioners. The paper concludes with direction for future research work; concentrating on development of a software package for accurately predicting productivity rates and assisting in the plant selection process.

The main objective of this article is to develop a theoretical formulation for predicting the response of CNTs reinforced beam under multiple impactors with general boundary conditions, using first-order shear deformation beam theory.

The rule of mixtures is implemented to derive the material properties of the beam. The nonlinear Hertz contact law is applied for simulation between impactors and the surface of the beam. A combination of approaches includes energy method, Ritz method and generalized Lagrange equations are used to extract the matrix form of equations of motion. The time-domain solution is obtained using implementing the well-known Runge Kutta 4th order method.

After examining the accuracy of the present method, the effects of the number of impactors include one impactor, and three impactors in various CNTs volume fraction are studied for CNTs reinforced beam with clamped-clamped, clamped-free and simply supported boundary conditions under the low-velocity impact. The most important finding of this article is that contact force and beam indentation at the middle of the beam in the case of one impactor are greater than those reported in the case of three impactors.

This article fulfills an identified need to study how CNTs reinforced beam behaviour with general boundary conditions under multiple low-velocity impacts can be enabled.

Iron deficiency anemia (IDA) is the most common nutritional anemia in the world and a pervasive health problem, especially in developing countries. Children under two years of age are more prone to be affected by IDA. The best strategy to prevent and treat IDA is to use iron supplements. This study aims to examine the factors associated with noncompliance (such as non-utilization or inconsistent usage) of iron drop supplementation among infants between 6 and 24 months old.

Online databases (PubMed, Scopus and SID) were searched to retrieve relevant articles published from inception up to July 2023. Among the 2,177 articles detected, after removing duplicate and irrelevant titles, 21 cross-sectional studies that met the authors’ inclusion criteria were included. Screening for articles and data extraction were conducted separately by two researchers.

The findings suggest that some factors related to mothers, such as education, knowledge, attitude and performance; some factors associated with child such as child’s gastrointestinal and dental complications; taste and smell of iron drops; and birth order and gender are the main determinants of adherence to iron supplementation.

It can be proposed that the most significant factors affecting the feeding of iron drops to children under the age of two include: the level of mother’s awareness, socio-economic status of the household and the occurrence of digestive complications following the supplementation. Given these observations, adopting proper policies toward improving the nutritional awareness of mothers and producing iron supplements with minimal side effects seems crucial.

The purpose of this paper is to present an applied method to design the low-speed contact between a mass and surface of a beam using an analytical solution based on the first-order shear deformation beam theory. Also, a simulation of impact process is carried out by ABAQUS finite element (FE) code.

In theoretical formulation, first strains and stresses are obtained, then kinetic and potential energies are written, and using a combination of Ritz and Lagrange methods, a set of system of motion equations in the form of mass, stiffness and force matrices is obtained. Finally, the motion equations are solved using Runge–Kutta fourth order method.

The von Mises stress contours at the impact point and contact force from the ABAQUS simulation are illustrated and it is revealed that the theoretical solution is in good agreement with the FE code. The effect of changes in projectile speed, projectile diameter and projectile mass on the results is carefully examined with particular attention to evaluate histories of the impact force and beam recess. One of the important results is that changes in projectile speed have a greater effect on the results than changes in projectile diameter, and also changes in projectile mass have the least effect.

This paper presents a combination of methods of energy, Ritz and Lagrange and also FE code to simulate the problem of sandwich beams under low velocity impact.

Herbal medicine has been used for the management of complications of diabetes. The purpose of this paper is to examine the anti-diabetic effects of Achillea millefolium extract on diabetic rats.

To this aim, 32 male Wistar rats were randomly assigned into four groups in which each group comprised eight rats. The four experimental groups were as follows: control group, diabetic control (DC) group (STZ; 50 mg/kg), diabetic rats, receiving 250 mg/kg hydro-alcoholic extract of the A. millefolium (DAM) and diabetic rats, receiving 5 mg/kg glibenclamide (DG). After 21 days of the treatment course, tissues of the kidney and blood samples were collected for histopathological, biochemical and molecular analysis.

The concentration of malondialdehyde (MDA) and glucose serum were markedly reduced in the DC group while significantly increased in DG and DAM groups (1.11 ± 0.57 to 19.4 ± 3.5 and 17.8 ± 1.2 p = 0.002 and 325 ± 0.18 to 223 ± 0.11 and 211 ± 0.32 p = 0.02, respectively). Also, the activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) were markedly reduced in the DC group while significantly increased in DAM and DG groups (9.1 ± 2.21 to 18.7 ± 3.81 and 14.9 ± 3.1 p = 0.03 and p = 0.02, respectively). The concentrations of creatinine, blood urea nitrogen (BUN) and urea were substantially decreased in DAM and DG groups as compared with the DC group (0.49 ± 0.02 to 0.27 ± 0.01 and 0.25 ± 0.01 p = 0.01, 15.6 ± 2.1 to 7.2 ± 0.68 and 8.6 ± 1.2 p = 0.02 and 114 ± 9.4 to 59.8 ± 5.2 and 64 ± 5.2 p = 0.03, respectively). Also, Bcl-2-associated X protein (BAX) expression was significantly decreased in DAM and DG groups as compared with the DC group (1.3 ± 0.32 to 0.91 ± 0.03 and 0.93 ± 0.02 p = <0.01) and Bcl-2 expression were significantly increased in DAM and DG groups as compared with the DC group (0.42 ± 0.05 to 0.88 ± 0.07 and 0.85 ± 0.06 p = 0.01).

Diabetes led to degenerative damages in the kidney of rats and increased the mRNA level of Bax, while treatment with A. millefolium could protect the kidney tissue against diabetes complications and increased the mRNA expression of Bcl-2. This study indicated that A. millefolium extracts not only improves renal function as a result of anti-oxidant activity but also modulates some biochemical factors in diabetic rats.

The purpose of this paper is to investigate the effect of graphene platelets (GPLs) on the low-speed contact between a mass and surface of a multi-layer polymer beam.

This problem is primarily organized by first-order shear deformation beam theory and nonlinear Hertz rule. GPLs are distributed along the beam thickness direction. The Halpin–Tsai micromechanics model is applied for computing the effective Young’s modulus of the GPLs/polymer composites. In the formulation process, the principle of conservation of energy is first used and the histories of results are extracted using the separation of variables and Runge–Kutta method.

In comparing the responses with the available data, a good agreement is observed. The effects of the weight fraction and distribution pattern on the impact response of polymer beam reinforced with GPLs are studied. Results show that contact force is increased, contact time and beam recess are decreased with increasing of weight fraction of GPLs. Also, among the different distribution patterns, the contact force depended on value of GPLs at the point of contact.

The effects of GPLs addition on the multi-layer polymer beam has a novelty in impact problems.

Higher level of customer satisfaction for halal products can be achieved by the effective adoption of halal certification through assessment and accreditation (HCAA). There are certain issues that seem detrimental towards the adoption of HCAA. The purpose of this paper is to identify the major barriers towards the adoption of HCAA and evaluate inter-relationships among them for developing the strategies to mitigate these barriers.

The barriers towards the adoption of HCAA are identified through an integrative approach of literature review and expert’s opinion. The inter-relationship among the identified barriers is evaluated using fuzzy-based decision-making trial and evaluation laboratory (fuzzy DEMATEL) technique, which categorises them into influential and influenced group.

The evaluation of inter-relationship among barriers using fuzzy DEMATEL indicates four influencing barriers and six influenced barriers towards the adoption of HCAA. Further, findings suggest an extensive government, and management support is vital in terms of commitment, resources and actions to realise the benefits attributed with HCAA.

The inter-relationship among barriers is contextual and based on the perception of experts which may be biased as per their background and area of expertise. This study pertains to a specific region and can be extended to the generalised certification system.

The empirical base of the research provides the inter-relationship among the barriers towards the adoption of HCAA which can be effectively used as input in the decision-making process by producers, manufacturers and distributor. The policy maker can analyse the cause group and effect group of barriers to formulate policies that would help in the adoption of HCAA.

Polyphenols are plant-derived bioactive compounds with some known hepato-protective effects. The purpose of this study is to evaluate the association between polyphenol consumption and risk of nonalcoholic fatty liver disease (NAFLD) and its related conditions such as impaired lipid profile and elevated hepatic enzymes.

A total of 196 NAFLD patients and 803 controls were enrolled in this case-control study. Biochemical and anthropometric measurements as well as polyphenol consumption during the previous year were assessed.

In unadjusted model, participants who consumed the third and fourth quartiles of polyphenols intake were less likely to have NAFLD in comparison to those who consumed the first quartile [odds ratio, OR: 0.48; 95 per cent confidence interval, CI: (0.30-0.77) and OR: 0.62; 95 per cent CI: (0.40-0.96), respectively]. In separate analysis of genders, this effect was seen only in male participants [OR: 0.29; 95 per cent CI: (0.14-0.58) and OR: 0.21; 95 per cent CI (0.10-0.42), respectively], and the association remained significant after adjustment for energy, body mass index, age and smoking.

Higher total polyphenol intake is associated with a decreased risk of NAFLD. Prospective studies are needed to confirm these results.

This study aims to examine the impact of ethical leadership style on the subjective well-being of health-care workers by examining the sequential mediating effects of perceived organizational support and perceived ethical-philanthropic corporate social responsibility (CSR).

Data were collected from frontline health-care workers (i.e. doctors and nurses). Further, to cope with the response burden during the acute wave of the coronavirus pandemic, this study used split-questionnaire design for data collection.

This study’s findings fully support the hypothesized framework of the study, illustrating that ethical leadership positively influenced the subjective well-being of health-care workers. Moreover, this study found that the ethical leadership and well-being relationship is sequentially mediated by perceived organizational support and perceived ethical-philanthropic CSR.

This study possesses practical implications for health-care institutions to encompass the agenda of developing ethically appropriate conduct in their administration and become genuinely concerned about health-care workers and society as well.

By highlighting the role of ethical leadership in participating in ethical and philanthropic CSR activities, this study possesses social implications for the well-being of health-care workers and society at large.

A positive and strong chain of perceptions about organizational support accorded to employees specifically and society at large emerges as an important sequential mediating mechanism that helps ethical leaders in hospital administration in building subjective well-being in their followers amid the COVID-19 pandemic.

Hepatitis C is one of the major health issues in both developed and developing countries. Hepatitis C virus (HCV) infection is more common in prisoners than in the general population. The purpose of this study was to determine the prevalence of HCV and its associated risk factors in Iranian male prisoners in Tehran.

In this cross-sectional study, the authors investigated the frequency and risk factors of hepatitis C infection among male prisoners in the Great Tehran Prison. Information on risk factors including the length of imprisonment, previous history of imprisonment, history of drug injection, history of tattooing, history of piercing, history of high-risk sex and family history of hepatitis C were extracted from patients’ records. To evaluate HCV status, blood samples were collected and tested.

In this study, 179 participants were included. Nine participants (5.0%, 95% CI, 2.3-9.3) were positive for hepatitis C. HCV infection was not significantly associated with age, marital status, education, previous history of imprisonment, length of imprisonment, piercing and high-risk sex; however, there was a significant association between a history of tattooing and a history of injecting drug use and Hepatitis C.

The prevalence of hepatitis C among male prisoners in Great Tehran Prison was 5% in this study, similar to recent studies on prisoners in Tehran. A history of drug injections as well as tattooing were the most important risk factors for hepatitis C in male prisoners.