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The primary driver for technological advancement in design methods is increasing part performance and reducing manufacturing cost. Design optimization tools, such as topology optimization, provide a mathematical approach to generate efficient and lightweight designs; however, integration of this design tool into industry has been hindered most notably by manufacturability. Innovative processes, such as additive manufacturing (AM), have significantly more design freedom than traditional manufacturing methods, providing a means to develop the complex designs produced by topology optimization. The layer-wise nature of AM leads to new design challenges such as the need for support material, influenced by part topology and build orientation. Previous works addressing approaches to limit support material often rely on the finite element discretization scheme, leading to a gap between solving academic and practical problems. This study presents an approach to simultaneously optimize part topology and build orientation with AM considerations. Utilizing the spatial density gradient in the topology optimization formulation, the dependence on the finite element discretization scheme is reduced. The proposed approach has the potential to significantly decrease support material, while having a minimal impact on structural performance. Both 2D and 3D academic test problems, as well as an aerospace industry example, demonstrate the proposed methodology is capable of generating high-quality designs. [ABSTRACT FROM AUTHOR]

Introduction Computerized pneumatic cuff pressure algometry ( CPA) using the DoloCuff is a new method for pain assessment. Intra- and inter-rater reliabilities have not yet been established. Our aim was to examine the inter- and intrarater reliabilities of DoloCuff measures in healthy subjects. Methods Twenty healthy subjects (ages 20 to 29 years) were assessed three times at 24-hour intervals by two trained raters. Inter-rater reliability was established based on the first and second assessments, whereas intrarater reliability was based on the second and third assessments. Subjects were randomized 1:1 to first assessment at either rater 1 or rater 2. The variables of interest were pressure pain threshold ( PT), pressure pain tolerance ( PTol), and temporal summation index ( TSI). Reliability was estimated by a two-way mixed intraclass correlation coefficient ( ICC) absolute agreement analysis. Reliability was considered excellent if ICC > 0.75, fair to good if 0.4 < ICC < 0.75, and poor if ICC < 0.4. Bias and random errors between raters and assessments were evaluated using 95% confidence interval ( CI) and Bland-Altman plots. Results Inter-rater reliability for PT, PTol, and TSI was 0.88 (95% CI: 0.69 to 0.95), 0.86 (95% CI: 0.65 to 0.95), and 0.81 (95% CI: 0.42 to 0.94), respectively. The intrarater reliability for PT, PTol, and TSI was 0.81 (95% CI: 0.53 to 0.92), 0.89 (95% CI: 0.74 to 0.96), and 0.75 (95% CI: 0.28 to 0.91), respectively. Conclusion Inter-rater reliability was excellent for PT, PTol, and TSI. Similarly, the intrarater reliability for PT and PTol was excellent, while borderline excellent/good for TSI. Therefore, the DoloCuff can be used to obtain reliable measures of pressure pain parameters in healthy subjects. [ABSTRACT FROM AUTHOR]

Bioimpedance (mfBIA) non‐invasively assesses cellular muscle health. Our aim was to explore whether mfBIA captures abnormal cellular muscle health in patients with Parkinson's Disease (PD) and how such changes are modulated with the use of Parkinson's medication. In patients with PD (n = 20) mfBIA measurements were made of biceps brachii, triceps, and extensor carpi radialis longus muscles of the more affected arm whilst at rest, using a mobile mfBIA device (IMPEDIMED, Australia). mfBIA and assessment of motor symptoms were performed in a pragmatic off‐medication state, as well as one and 3 h after oral intake of 200 mg levodopa. Age and sex‐matched healthy subjects (HC; n = 20) served as controls. PD and HC mfBIA parameters were compared by applying an unpaired two‐tailed adjusted t‐test and ANOVA with Tukey's correction for multiple comparisons (p ≤ 0.05). The PD group consisted of 13 men (71 ± 17 years) and 7 women (65 ± 7 years). Independent of medication, internal (Ri) and external resistance (Re) were found to be significantly higher, and membrane capacitance (Mc) significantly lower, in m.biceps brachii in PD subjects compared to HC. Center frequency (fc) was significantly higher in m.biceps brachii of PD subjects in the "medication‐off" state. There was no difference between PD and HC in mfBIA parameters in the measured extensor muscles. The upper limb flexor muscle shows a difference in mfBIA parameters in PD compared to HC. mfBIA may be useful in the diagnosis and assessment of PD patients and is objective, non‐invasive, reliable, and easy to use. Bioimpedance (mfBIA) is an objective, non‐invasive, reliable method when assessing the condition of upper limb muscles in Parkinson's patients. For M. Biceps brachii in PD subjects, internal (Ri) and external resistance (Re) were found to be significantly higher, and membrane capacitance (Mc) significantly lower, compared to healthy subjects. Centre frequency (fc) is higher in PD prior to PD medication, but decreases significantly following medication. [ABSTRACT FROM AUTHOR]

The condition of active muscles determines an individual′s ability to carry out daily activities and has implications for an athlete′s performance. Multi‐frequency bioimpedance (mfBIA) is a non‐invasive, well‐known, validated, and much used method to assess muscle condition. However, it is rarely used to its full potential. Our aim was to apply mfBIA fully in the assessment of an adult healthy population, to compare muscle condition in different functional rested muscle groups, with age, and between men and women, and establish a control data set. Fifty healthy subjects (25 men/25 women) aged 20–69 years, participated. mfBIA measurements at a frequency range of 4–1000 kHz were taken from muscles of the lower and the upper extremities, the upper back, and the hand. Data were analyzed using ImpediMed software, giving Impedance, Resistance, Reactance, Phase Angle, Center Frequency, external and internal Resistance, and Membrane Capacitance. Differences between means were tested for statistical significance. A P value >0.05 was considered nonsignificant. While no difference in the mfBIA parameters was seen with age, a highly significant gender difference was seen. At rest, women′s muscles cf men's showed a significantly higher center frequency and intra‐ and extra‐cellular resistance, while the membrane capacitance was lower. A set of values for mfBIA parameters for healthy adult individuals are given for some of the main muscles which are frequently part of muscle assessment. The documented gender difference in muscle condition at rest has important implications in work situations, during physical rehabilitation and when training for competitive sports. [ABSTRACT FROM AUTHOR]