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Thermally induced stresses and strains in a CuCrZr alloy–W joint are analyzed using finite element methods. The effect on stress and strain of using different materials as interlayers to join CuCrZr to W is examined and compared to geometries without an interlayer (sharp interface). Oxygen free high conductivity copper (OFHC) and several types of graded structures formed with OFHC and W are used as the different interlayer materials. Temperature dependence of the properties in addition to plasticity and strain hardening are considered in the finite element formulation. The use of an OFHC Cu interlayer results in the maximum reduction of stress compared to the sharp interface, but also in large highly localized plastic strains that increase under operation conditions. The residual stress is slightly higher for OFHC/W graded interlayers, but still significantly lower than for the sharp interface. However, a notable difference for the graded interlayers is that the plastic strain is greatly reduced compared with the OFHC interlayer. [Copyright &y& Elsevier]

Recovery of strength and endurance post heart transplant (HTx) has remained relatively slow. Factors that limit early rehabilitation include sternotomy precautions and corticosteroid myopathy. We propose that specialized, comprehensive rehabilitation program (COLTT) can be initiated immediately after discharge to (1) improve functional outcomes (2) decrease hospital readmission. This is a retrospective analysis of 14 patients (age 20 - 71 years, mean 48 years, 12 male) post orthotropic HTx (2018 - 2020). Patients were enrolled, on average, 2.9 days after hospital discharge. COLTT is a multidisciplinary (respiratory and physical therapy), daily rehabilitation program (2.5 hours) with focus on return to function through strength, balance, and endurance training. Six-minute walk test (6MWT), 1-minute sit-to-stand (STS), left and right single leg stand (SLS) and walk speed were assessed pre- and post-COLTT: Published normative data for the outcome measures was used to establish patient goals. Enright equation was used to calculate patients' percent predicted 6MWD. Paired t-tests were used to assess pre/post gains using SPSS statistics software. The number of visits required to reach COLTT program goals was 18.85 visits (±7.68). 6MWT improved from 1008m (±369.3) to 1734m (±299.1), P<0.001. STS improved from 6.714 (±7.332) to 25.29 (±5.21) repetitions, P<0.001. Walk speed improved from 1.917 mph (±0.521) to 2.821 mph (±0.669), P <0.05. Right SLS improved from 7.753 seconds (±7.179) to 22.58 (±20.93), P=0.004, and left SLS from 9.545 (±17.23) to 15.36(±17.5) seconds, P=0.065 (borderline significant). 71% of the patients on 6MWT achieved >80% target level, based on Enright equation. In the 6 months following hospital discharge, only 2 had readmission for infection. None had readmission for deconditioning or cardiac decompensation. Outcomes measures such as 6MWT and STS provide objective data of rehabilitation progress. Combining strength, balance, and endurance rehabilitation during COLTT reached functional outcomes near the level of healthy individuals in 19 visits on average. There were no unplanned hospitalizations attributable to COLTT. This implementation study supports that HTx recipients can be trained as healthy individuals and benefit from intensive rehabilitation shortly after surgery. [ABSTRACT FROM AUTHOR]

Acute lymphoblastic leukemia (ALL) is the most common cancer in childhood worldwide and Mexico has reported one of the highest incidence rates. An infectious etiology has been suggested and supported by epidemiological evidences; however, the identity of the involved agent(s) is not known. We considered that early transmitted lymphotropic herpes viruses were good candidates, since transforming mechanisms have been described for them and some are already associated with human cancers. [ABSTRACT FROM AUTHOR]

Background:Allergies have been described as protective factors against the development of childhood acute leukaemia (AL). Our objective was to investigate the associations between allergy history and the development of AL and acute lymphoblastic leukaemia (ALL) in children with Down syndrome (DS).Methods:A case-control study was performed in Mexico City. The cases (n=97) were diagnosed at nine public hospitals, and the controls (n=222) were recruited at institutions for children with DS. Odds ratios (OR) were calculated.Results:Asthma was positively associated with AL development (OR=4.18; 95% confidence interval (CI): 1.47-11.87), whereas skin allergies were negatively associated (OR=0.42; 95% CI: 0.20-0.91).Conclusion:Our findings suggest that allergies and AL in children with DS share biological and immune mechanisms. To our knowledge, this is the first study reporting associations between allergies and AL in children with DS. [ABSTRACT FROM AUTHOR]

Background: For a child to develop acute leukaemia (AL), environmental exposure may not be sufficient: interaction with a susceptibility factor to the disease, such as Down syndrome (DS), may also be necessary. We assessed whether breastfeeding and early infection were associated with the risk of developing AL in children with DS.Methods: Children with DS in Mexico City, and either with or without AL, were the cases (N=57) and controls (N=218), respectively. Population was divided in children with AL and with acute lymphoblastic leukaemia (ALL) and also in children < or = 6 and >6 years old.Results: Breastfeeding and early infections showed moderate (but not significant) association for AL, whereas hospitalisation by infection during the first year of life increased the risk: odds ratios (confidence interval 95%) were 0.84 (0.43-1.61), 1.70 (0.82-3.52); and 3.57 (1.59-8.05), respectively. A similar result was obtained when only ALL was analysed.Conclusion: We found that breastfeeding was a protective factor for developing AL and ALL, and during the first year of life, infections requiring hospitalisation were related to a risk for developing the disease in those children with DS >6 years of age. These data do not support the Greaves's hypothesis of early infection being protective for developing ALL. [ABSTRACT FROM AUTHOR]