Micromotion measurement at the interfaces of cemented tibial endoprosthetic replacements: A new standardized in vitro model using open-cell rigid foam.

Early aseptic loosening following primary total knee arthroplasty related to several factors might appear at the interface implant-cement or cement-bone. A standardized in vitro model might provide information on the relevance of single variable parameter of cementation including technique and cement respectively bone structure on fixation strength. Micromotion measurement using different directions of load should detect the primary stability of the interfaces. An open-cell rigid foam model was used for cementation of PFC-Sigma tibial trays with Palacos®. Pins were applied to the model for continuous non-destructive measurement. Relative micromotions for rotation, valgus-varus and extension flexion stress were detected at the interfaces as well as cement penetration was measured. The reproducibility of the measurement could be shown for all interfaces in extension-flexion movements. For rotation a negative trend was shown for the interface cement-prosthesis and cement-bone concerning varus-valgus stress reflecting varying surgical cementation technique. More micromotion related to extension-flexion force might reflect the design of the implant. Measurement of relative micromotion and cement distribution appear accurate to detect small differences of movement at different interfaces of cemented tibial implants and the results are reproducible for most parameter. An increased number of specimens should achieve statistical relevance for all measurements.

Contraction pressure analysis using optical imaging in normal and MYBPC3-mutated hiPSC-derived cardiomyocytes grown on matrices with tunable stiffness.

Current in vivo disease models and analysis methods for cardiac drug development have been insufficient in providing accurate and reliable predictions of drug efficacy and safety. Here, we propose a custom optical flow-based analysis method to quantitatively measure recordings of contracting cardiomyocytes on polydimethylsiloxane (PDMS), compatible with medium-throughput systems. Movement of the PDMS was examined by covalently bound fluorescent beads on the PDMS surface, differences caused by increased substrate stiffness were compared, and cells were stimulated with ß-agonist. We further validated the system using cardiomyocytes treated with endothelin-1 and compared their contractions against control and cells incubated with receptor antagonist bosentan. After validation we examined two MYBPC3-mutant patient-derived cell lines. Recordings showed that higher substrate stiffness resulted in higher contractile pressure, while beating frequency remained similar to control. ß-agonist stimulation resulted in both higher beating frequency as well as higher pressure values during contraction and relaxation. Cells treated with endothelin-1 showed an increased beating frequency, but a lower contraction pressure. Cells treated with both endothelin-1 and bosentan remained at control level of beating frequency and pressure. Lastly, both MYBPC3-mutant lines showed a higher beating frequency and lower contraction pressure. Our validated method is capable of automatically quantifying contraction of hiPSC-derived cardiomyocytes on a PDMS substrate of known shear modulus, returning an absolute value. Our method could have major benefits in a medium-throughput setting.

Mulheres no trabalho militar: uma revisão bibliométrica e crítica / Mujeres en el trabajo militar: una revisión bibliométrica y crítica / Women in military work: a bibliometric and critical review

Resumo: O trabalho militar, historicamente, é uma profissão predominantemente masculina. A crescente inserção das mulheres nas instituições militares tem enfrentado entraves importantes. A presente revisão bibliométrica objetivou mapear e analisar criticamente a literatura indexada sobre gênero no contexto militar, pretendendo especificamente identificar características, tendências e lacunas da produção científica sobre o tema nos últimos 10 anos na psicologia. Além da ausência de estudos brasileiros ou em língua portuguesa, identificou-se predominância de métodos quantitativos e de participantes homens nas pesquisas. O tema mais abordado foi o trauma sexual militar. Aponta-se a necessidade de mais investigações com mulheres militares em contexto brasileiro.

Resumen: El trabajo militar ha sido históricamente una profesión predominantemente masculina. La creciente inserción de la mujer en las instituciones militares ha enfrentado importantes obstáculos. La presente revisión bibliométrica tuvo como objetivo mapear y analizar críticamente la literatura indexada sobre género en el contexto militar, con el objetivo de identificar características, tendencias y vacíos en la producción científica sobre el tema en los últimos 10 años. Además de la ausencia de estudios brasileños o en lengua portuguesa, se identificó predominio de métodos cuantitativos y participantes del sexo masculino en la investigación. El tema más discutido fue el trauma sexual militar. Se destaca la necesidad de más investigaciones con mujeres militares en el contexto brasileño.

Abstract: Military work is, historically, a predominantly male profession. The growing insertion of women in military institutions has faced important obstacles. This bibliometric review aimed to map and critically analyze the indexed literature on gender in the military context, specifically intending to identify characteristics, trends and gaps in scientific production on the topic in the last 10 years. In addition to the absence of Brazilian or Portuguese-language studies, a predominance of quantitative methods and male participants was identified. The most discussed topic was military sexual trauma. The need for more research with military women in the Brazilian context is highlighted.