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South America is a heterogeneous continent, with diverse prison realities. Its prison population is estimated at 600,000 inmates, of whom 10,000 are declared insane. Physical and mental health care supplied to the inmates is precarious and preventive programs in progress are rare. The authors’ comment on the Roman Law tradition and describe the situation in Brazil and Argentina, from the point of view of their legal backgrounds. They also consider the kind of mental health resources found and the types of treatment offered, mainly in Forensic Psychiatric Hospitals. Their conclusion emphasizes the need to improve the conditions of penitentiaries in South America, which, because of their deficiencies, often violate the human rights of prisoners.

Fused filament fabrication of continuous-fiber-reinforced polymers is a promising technique to achieve customized high-performance composites. However, the off-axis tensile strength (TS) and Mode I fracture toughness of fused filament fabricated (FFFed) continuous-glass-fiber-reinforced (CGFR) nylon are unknown. The purpose of this paper is to investigate the mechanical and fracture behavior of FFFed CGFR nylon with various fiber content and off-axis fiber alignment.

Tensile tests were performed on FFFed CGFR-nylon with 9.5, 18.9 and 28.4 fiber vol. %. TS was tested with fiber orientations between 0^∘ and 90^∘ at 15^∘ intervals. Double cantilever beam tests were performed to reveal the Mode I fracture toughness of FFFed composites.

TS increased with increasing fiber vol. % from 122 MPa at 9.5 vol. % to 291 MPa at 28 vol. %. FFFed nylon with a triangular infill resulted in 37 vol. % porosity and a TS of 12 MPa. Composite samples had 11–12 vol. % porosity. TS decreased by 78% from 291 MPa to 64 MPa for a change in fiber angle θ from 0^∘ (parallel to the tensile stress) to 15^∘. TS was between 27 and 17 MPa for 300 < θ < 900. Mode I fracture toughness of all the composites were lower than ∼332 J/m2.

Practical applications of FFFed continuous-fiber-reinforced (CFR) nylon should be limited to designs where tensile stresses align within 15^∘ of the fiber orientation. Interlayer fracture toughness of FFFed CFR composites should be confirmed for product designs that operate under Mode I loading.

To the best of the authors’ knowledge, this is the first study showing the effects of fiber orientation on the mechanical behavior and effects of the fiber content on the Mode I fracture toughness of FFFed CGFR nylon.

This study focuses on a specific method of meat production that involves carcass purchase and meat production by packing facilities with a novel two-stage model that simultaneously considers location-routing and inventory-production operating decisions. The considered problem aims to reduce variable and fixed transportation and production costs, inventory holding cost and the cost of opening cold storage facilities.

The proposed model encompasses a two-stage model consisting of a single-echelon and a three-echelon many-to-many network with deterministic demand. The proposed model is a mixed-integer linear programming (MILP) model which was tested with the general algebraic modelling system (GAMS) software for a real-world case study in Iran. A sensitivity analysis was performed to examine the effect of retailers' holding capacity and supply capacity at carcass suppliers.

In this research, the number of products transferred at each level, the number of products held, the quantity of red meat produced, the required cold storage facilities and the required vehicles were optimally specified. The outcomes indicated a two percent (2%) decrease in cost per kg of red meat. Eventually, the outcomes of the first and second sensitivity analysis indicated that reduced retailers' holding capacity and supply capacity at carcass suppliers leads to higher total costs.

This research proposes a novel multi-period location-inventory-routing problem for the red meat supply chain in an emerging economy with a heterogeneous vehicle fleet and logistics decisions. The proposed model is presented in two stages and four-echelon including carcass suppliers, packing facilities, cold storage facilities and retailers.

The aim of this work is to explain the final negotiated prices for some of the most famous transfers of football players over the last twelve years (2007–2018).

The article analyses different values for forwards taken from the sports website Transfermarkt, developing a statistical model based on personal, performance, risk, environmental and popularity variables. From those values, the article finds an explanation for the final prices paid for 20 superstar players based on a combination of real option valuations, incorporating the players' life cycles and game theory.

The authors find that in a large percentage (70%) of the analysed cases, the price paid was higher than the intrinsic market value resulting from Transfermarkt, implying the existence of monopolistic rents, paid as “growth options” on prices from different negotiating conditions. On occasions, the final prices also exceed the value of the growth option, calculated under neutral bargaining conditions, highlighting the lack of economic viability of important transfers, leading to financial difficulties for the clubs involved.

The algorithm provides more flexibility and realism than previous proposals, based on the life cycle of football players, introducing the uncertainty and volatility of projections through Monte Carlo simulation, the capacity of clubs to bargain a price at any point of the contract and finally, the buyer's ability to transfer the player if his subsequent performance is not as expected.

The purpose is to create an algorithm that optimizes the trajectories that an autonomous vehicle must follow to reduce its energy consumption and reduce the emission of greenhouse gases.

An algorithm is presented that respects the dynamic constraints of the robot, including the characteristics of power delivery by the motor, the behaviour of the tires and the basic inertial parameters. Using quadratic sequential programming with distributed and non-monotonous search direction (Quadratic Programming Algorithm with Distributed and Non-Monotone Line Search), an optimization algorithm proposed and developed by Professor K. Schittkowski is implemented.

Relations between important operating variables have been obtained, such as the evolution of the autonomous vehicle’s velocity, the driving torque supplied by the engine and the forces acting on the tires. In a subsequent analysis, the aim is to analyse the relationship between trajectory made and energy consumed and calculate the reduction of greenhouse gas emissions. Also this method has been checked against another different methodology commented on in the references.

The main limitation comes from the modelling that has been done. As greater is the mechanical systems analysed, more simplifying hypotheses should be introduced to solve the corresponding equations with the current computers. However, the solutions are obtained and they can be used qualitatively to draw conclusions.

One main objective is to obtain guidelines to reduce greenhouse gas emissions by reducing energy consumption in the realization of autonomous vehicles’ trajectories. The first step to achieve that is to obtain a good model of the autonomous vehicle that takes into account not only its kinematics but also its dynamic properties, and to propose an optimization process that allows to minimize the energy consumed. In this paper, important relationships between work variables have been obtained.

The idea is to be friendly with nature and the environment. This algorithm can help by reducing an instance of greenhouse gases.

Originality comes from the fact that we not only look for the autonomous vehicle’s modelling, the simulation of its motion and the analysis of its working parameters, but also try to obtain from its working those guidelines that are useful to reduce the energy consumed and the contamination capability of these autonomous vehicles or car-like robots.

The purpose of this study is to apply the Meshless Local Petrov–Galerkin (MLPG) method to solve the bending problems of linear viscoelastic plates, considering Reissner’s theory.

The weak formulation for the set of equations that govern Reissner’s plate theory is implemented in conjunction with the integral formulation applied to viscoelastic constitutive expressions. A meshless method based on the Moving Least Squares (MLS) approximation is considered in the numerical implementation. The final equation system is assembled by adopting simple and efficient schemes for numerical integration, considering a simplified formulation through centralization of the local interpolation domains and Gaussian quadrature at the same field point. The results obtained are compared with available solutions to demonstrate the efficiency of the proposed formulation.

The hereditary integral approach proved to be the most general way to analyze the viscoelastic problem, especially when applied together with the modified scheme for numerical integration. In addition, the variable changing technique is demonstrated to be an efficient formulation for solving shear-locking effects in thin plate problems.

The differential of the present study is related to the manner in which the properties of linear viscoelastic materials are considered in the formulation. Although most authors consider this point through the application of the correspondence principle, the present study works with a hereditary integral formulation. In addition, the variable changing technique is applied to solve the shear-locking effects, and an alternative approximation technique is considered to speed up the numerical integration process.

This issue is a selected bibliography covering the subject of leadership.

This paper examines the effect of R&D investments on the market value of firms in the U.S., Germany, and Japan. Specially, this paper investigates the empirical validity of the widely‐held economic views that suggest that the stock‐market oriented U.S. financial system leads to more corporate myopia and hence to less longer‐term investments such as R&D than the bank‐oriented German and Japanese firms. Findings include that U.S. firms invest in R&D as much as their counterparts in Japan and Germany; the market places a significant and positive value on R&D investments by U.S. firms, though lower than German and Japanese firms; and there are notable differences among the three nations with respect to several other variables. The overall evidence lends little support to the corporate myopia view on U.S. firms.

In this paper, the authors tested if promoting the workforce's happiness (through high performance work policies or HPWP) and well-being in European Public companies relates to their profitability (return on equity, ROE), market risk (beta) and stock price return. Also, the authors tested if investors have a performance benefit if they buy a portfolio screened with companies with HPWP.

The authors proxied the quality of the HPWP efforts in the first method with the Refinitiv workforce score. They used this data in an unbalanced panel of eastern, western, northern and southern Europe companies from 2011 to 2022. The panel data also included the ROE, the market risk (beta) and the stock price return of these companies. The authors estimated the corresponding regressions with the panel data and tested the relationship between the workforce score and these three variables. In a second method, they simulated the weekly performance of a portfolio that invested only in European companies with high standards in their HPWP and compared its performance against a conventional market portfolio (with no HPWP screening).

In the first method, the authors found no significant relationship between the workforce score and the ROE, beta, or stock price return in the panel regression, controlling for random effects. In the second one, they found no over or underperformance in the HPWP portfolio against the European market one in the second method.

The results suggest that there is no risk or cost for European Public companies and investors alike if they promote, with better HPWP, the happiness and well-being of their workforce. The findings suggest that if European companies promote HPWP, there will be no adverse impact on their profits, market risk, or stock price performance. Also, investors will not lose performance (against a conventional market portfolio) if they screen their portfolios with this type of workforce-friendly companies.

Increase the scarce literature on the test of the workforce score with company profitability (ROE), stock market price variation and stock market risk level.

The purpose of this paper is to investigate the employee performance of firms with a plus or minus specification in their bond credit ratings (i.e. firms near a broad bond rating change) because prior research suggests that these borderline firms demonstrate different behavior, relative to firms that are not near a broad bond rating change.

The authors use regression analysis to test the research question.

The authors posit and find that employees work harder when their firms are borderline in the context of bond credit ratings. The authors obtain similar results using firms on the Standard and Poor’s CreditWatch list. The authors also find that the results become stronger for firms with higher ability managers or when firms are faced with a more volatile business environment.

The results suggest that managers of these borderline firms have stronger incentives to improve employee performance. The study contributes to the large research stream on bond rating in finance literature and the research stream on employee performance in management and accounting literature. Specifically, our findings not only strengthen the notion in Kisgen (2006) that borderline companies often show different behavior, compared to average companies, but also can lead to a more comprehensive understanding of the determinants of employee performance. The study, to the authors’ knowledge, is one of the few empirical studies that directly examine the employee behavior (i.e. performance) when their firms are at the borderline in the context of bond credit ratings.