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Background: Powder bed fusion (PBF) offers enhanced opportunities to manufacture complex components with a high degree of geometric freedom. However, understanding and designing for mechanical properties remains challenging due to numerous factors, such as processing parameters, building direction, and heat treatments. Objective: In this study, we revealed that the As-built and heat-treated mechanical properties differ from those achieved through traditional manufacturing methods, even when using the same alloy and heat treatments. This phenomenon arises from the intricated microstructures and porosity caused by the repetitive, rapid heating/cooling process involved. Results: To quantitatively investigate the properties, the conventional heat treatments combining a hot isostatic pressing (HIP), solution, and aging treatment, were conducted on 17-4 PH stainless steel printed in both horizontal and vertical directions. Our findings demonstrate that HIP, coupled with aging treatment, was the most effective method for reducing porosity, and enhancing hardness and yield strength by 56 % and 118 % , respectively, while there was a slight decrease in elongation by 5.6 % . The high temperature and pressure during HIP enabled the recrystallization of As-built microstructure into lath martensite, and the aging treatment facilitated the production of precipitates to enhance the strength. The solution treatment, however, resulted in poor elongation to 9.3 % while the yield and tensile strength showed similar levels to As-built parts due to insufficient time to recrystallize the As-built microstructure. Conclusions: We believe these results will offer valuable insights into the manufacturing and post processing not only of PBF 17-4PH stainless steel but also of other alloys. [ABSTRACT FROM AUTHOR]

Background: Observational studies suggest inverse associations between wholegrain intake and body weight gain. Only few controlled intervention studies have supported this association and few compare effects of different grain varieties.Objective: To investigate how wholegrain wheat (WGW) and rye compared with refined wheat (RW) affect body weight and composition and appetite sensation.Design: Seventy overweight/obese adults participated in this 6-week randomized parallel study, in which they replaced their habitual cereal foods with RW, WGW or wholegrain rye (WGR). Further, a 4 h postprandial test meal challenge was completed with meals corresponding to diet allocation in the beginning and after the intervention. Body weight and composition, fasted blood samples, compliance and 4-day dietary intake were obtained before and after the intervention period. Appetite and breath hydrogen excretion was assessed during the postprandial test meal challenge.Results: Diet allocation affected body weight significantly (P=0.013) and tended also to affect fat mass (P=0.065). Both body weight and fat mass decreased more in the WGR group (-1.06±1.60 and -0.75±1.29 kg, respectively) compared with the RW group (+0.15±1.28 and -0.04±0.82 kg, respectively; P<0.01 and P<0.05, respectively). Further, the decrease in fat mass in the WGR group tended to exceed that in the WGW group (P=0.07). Overall, no effect of diet on appetite sensation was observed; however, energy intake from study products was ~200 kcal lower in the WGR group when compared with that in the RW group (P<0.05), although total energy intake did not differ between groups.Conclusions: Our results support a role for WGR foods in body weight regulation, when provided ad libitum. The effect may be mediated by satiation reflected in a reduction in energy intake, mainly from the wholegrain products without compensation in other parts of the diets, despite no difference in appetite. [ABSTRACT FROM AUTHOR]

Objectives: Prior studies have suggested a relationship between dehydration and poor cognitive performance. The present study examined the relationships among hydration status, declarative memory and working memory skills, and blood pressure in a sample of older community dwelling females. Design: Data was analyzed from a larger study; relationships among hydration status, blood pressure, and cognitive measures were assessed with correlation and meditational analyses. Setting: Laboratory. Participants: 21 postmenopausal women (mean age 60.3, SD 8.03). Measures: Hydration status was measured using bioelectrical impedance, baseline blood pressure was assessed using a Colin Pressmate, and cognition was examined using the Auditory Verbal Learning Test and Auditory Consonant Trigrams. Results: Bioelectrical impedance total body water by weight was found to be related to working memory, r =.47, p =.04, and memory skills, r =.54, p =.01. Total body water by weight was also found to be related to diastolic blood pressure, r = −.56, p =.01, which in turn was related to working memory, r = −.67, p =.002, and declarative memory, r = −.57, p =.009, skills. When diastolic blood pressure was accounted for, the relationship between hydration status and cognitive skills was attenuated. A similar pattern of results was seen for systolic blood pressure, although findings did not reach statistical significance. Conclusions: Results emphasize the importance of considering hydration status and blood pressure when interpreting cognitive performance in older adults. [ABSTRACT FROM AUTHOR]

Structural components subject to cyclic stress can succumb to fatigue, causing them to fail at stress levels much lower than if they were under static mechanical loading. However, despite extensive research into the mechanical properties of carbon nanotube structures for more than a decade, data on the fatigue behaviour of such devices have never been reported. We show that under repeated high compressive strains, long, vertically aligned multiwalled nanotubes exhibit viscoelastic behaviour similar to that observed in soft-tissue membranes. Under compressive cyclic loading, the mechanical response of the nanotube arrays shows preconditioning, characteristic viscoelasticity-induced hysteresis, nonlinear elasticity and stress relaxation, and large deformations. Furthermore, no fatigue failure is observed at high strain amplitudes up to half a million cycles. This combination of soft-tissue-like behaviour and outstanding fatigue resistance suggests that properly engineered nanotube structures could mimic artificial tissues, and that their good electrical conductivity could lead to their use as compliant electrical contacts in a variety of applications. [ABSTRACT FROM AUTHOR]

Copyright of Der Urologe A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Der Urologe A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Der Urologe B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)