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A fast method called the 'inverse approach' for sheet forming modeling is based on the assumptions of the proportional loading and simplified tool actions. To improve the stress estimation, the pseudo-inverse approach was recently developed: some realistic intermediate configurations are geometrically determined to consider the deformation paths; two new efficient algorithms of plastic integration are proposed to consider the loading history. In the direct scalar algorithm (DSA), an elastic unloading-reloading factor y is introduced to deal with the bending-unbending effects; the equation in unknown stress vectors is transformed into a scalar equation using the notion of the equivalent stress, thus the plastic multiplier [DELTA][lambda] can be directly obtained without iterative resolution scheme. In the [gamma]-return mapping algorithm, the equivalent plastic strain increment estimated by DSA is taken as the initial solution in Simo's return mapping algorithm, leading to a stable, efficient, and accurate plastic integration scheme. The numerical experience has shown that these two algorithms give a considerable reduction of CPU time in the plastic integration. [DOI: 10.1115/1.2738125]

A numerical study is carried out on the thermoplastic wheat starch injection molding process. The simulation is performed using currently available molding software to determine optimal molding parameters. The molding of a standardized sample for tensile test is considered. It is shown that the conventional continuum mechanics equations can be used for modeling the injection molding of thermoplastic starch. These equations are solved using the finite element method. Comparisons with some experimental results are presented, indicating good agreement. Data on the processing of thermoplastic starch and several other basic aspects are also provided., INTRODUCTION Thermoplastic Starch Starch is the principal constituent of cereals and legumes such as wheat, corn, rice, and peas. Its competitive price, availability, and biodegradability, favored the development of a [...]

The gradual development of government policies for ecological transition in the modern construction sector leads researchers to explore new alternative and low environmental impact materials with a particular focus on bio-sourced materials. In this perspective, the mechanical, thermal insulation, and the sound absorption performances of a spent coffee grounds/potato starch bio-based composite were analyzed for potential application in buildings. Based on thermal conductivity and diffusivity tests, the coffee grounds waste biocomposite was characterized as an insulating material comparable with conventional thermal insulation materials of plant origin. Acoustical tests revealed absorption coefficients in the same range as other conventional materials used in building acoustical comfort. This bio-sourced material presented a sufficient compressive mechanical behavior for non-load-bearing structures and a sufficient mechanical capacity to be shaped into building bricks. Mechanical, thermal, and acoustic performances depend on the moisture environment. The groundwork was laid for an initial reflection on how this composite would behave in two opposite climates: the continental climate of Reims in France and the tropical climate of Belém in Brazil.

In order to determine the required duration of whole-body exposure to extreme cold (-110 °C) in males and females for achieving the same cold-induced response, a mathematical model of skin cooling kinetics was developed. This modeling is derived from the implementation of a new experimental cryotherapy protocol to obtain continuous skin temperature maps over time. Each 3-min whole-body cryostimulation session was divided into six incremental sessions of 30 s carried out over six consecutive days. Seventeen young, healthy subjects (8 males aged 22.6 ±3.0 years and 9 females aged 23.7 ±4.7 years) agreed to participate in this study. The smallest sex-related difference in temperature was found in the trunk area (2.93 °C after 3 min) while the greatest temperature drop was found in the lower limbs (5.92 °C after 3 min). The largest temperature variation was observed between the trunk and the lower limbs, and peaked at 2.67 °C in males and 6.99 °C in females. For both sexes, skin cooling kinetics showed a strong transient exponential type decrease followed by linear regression behavior. It appeared that for achieving the same cold-induced response, the required duration of cryostimulation is longer for males. For example, a trunk skin cooling of -12 °C could be achieved in 125s for females vs 170s for males (+36% longer); for the lower limbs, the same skin cooling magnitude could be reached after 87s for females vs 140s for males (+62% longer)., Competing Interests: Declaration of competing interest The authors report no conflict of interests regarding the publication of this paper., (Copyright © 2020. Published by Elsevier Inc.)

Background: Deep dermatophytosis is a severe and sometimes life-threatening fungal infection caused by dermatophytes. It is characterized by extensive dermal and subcutaneous tissue invasion and by frequent dissemination to the lymph nodes and, occasionally, the central nervous system. The condition is different from common superficial dermatophyte infection and has been reported in patients with no known immunodeficiency. Patients are mostly from North African, consanguineous, multiplex families, which strongly suggests a mendelian genetic cause., Methods: We studied the clinical features of deep dermatophytosis in 17 patients with no known immunodeficiency from eight unrelated Tunisian, Algerian, and Moroccan families. Because CARD9 (caspase recruitment domain-containing protein 9) deficiency has been reported in an Iranian family with invasive fungal infections, we also sequenced CARD9 in the patients., Results: Four patients died, at 28, 29, 37, and 39 years of age, with clinically active deep dermatophytosis. No other severe infections, fungal or otherwise, were reported in the surviving patients, who ranged in age from 37 to 75 years. The 15 Algerian and Tunisian patients, from seven unrelated families, had a homozygous Q289X CARD9 allele, due to a founder effect. The 2 Moroccan siblings were homozygous for the R101C CARD9 allele. Both alleles are rare deleterious variants. The familial segregation of these alleles was consistent with autosomal recessive inheritance and complete clinical penetrance., Conclusions: All the patients with deep dermatophytosis had autosomal recessive CARD9 deficiency. Deep dermatophytosis appears to be an important clinical manifestation of CARD9 deficiency. (Funded by Agence Nationale pour la Recherche and others.).