Female-biased sexual size dimorphism (SSD) is widespread in many invertebrate taxa. One hypothesis for the evolution of SSD is the dimorphic niche hypothesis, which states that SSD evolved in response to the different sexual reproductive roles. While females benefit from a larger body size by producing more or larger eggs, males benefit from a faster development, which allows them to fertilize virgin females (protandry). To test this hypothesis, we studied the influence of temperature and intraspecific density on the development of the grasshopper, Chorthippus montanus. We reared them in monosexual groups under different conditions and measured adult body size, wing length, nymphal mortality, and development time. The present study revealed an inverse temperaturesize relationship: body size increased with increasing temperature in both sexes. Furthermore, we found intersexual differences in the phenotypic response to population density, supporting the dimorphic niches hypothesis. At a lower temperature, female development time increased and male body size decreased with increasing density. Because there was no food limitation, we conclude that interference competition hampered development. By contrast to expectations, mortality decreased with increasing density, suggesting that interference did not negatively affect survival. The present study shows that sex-specific niche optima may be a major trigger of sexual dimorphisms.

Background In the aging population of Western societies, an increasing number of older adults have multiple chronic diseases. As multifaceted health problems imply the involvement of several healthcare professionals, multimorbid older people frequently face a fragmentation of health care. Addressing these challenges, we developed a local, collaborative, stepped, and personalized care management approach (LoChro-Care) and evaluated its effectiveness. Methods A two-group, parallel randomized controlled trial was conducted comparing LoChro-Care recipients (IG) to participants with usual care (CG). Patients aged 65 + with chronic conditions were recruited at inpatient and outpatient departments of the Medical Center, University of Freiburg. Participants were allocated using block randomization (nIG = 261, nCG = 263). LoChro-Care comprised individualized care provided by chronic care managers with 7 to 13 contacts over 12 months. Questionnaires were given at 3 time points (T0: baseline, T1: after 12 months, T2: after 18 months). The primary outcome was the physical, psychological, and social health status represented by a composite score of functional health and depressive symptoms. Secondary outcomes were the participants’ evaluation of their health care situation, health-related quality of life (HRQL), and life-satisfaction (LS). The data were analyzed using linear mixed modelling. Results We analyzed N = 491 participants (nIG = 244, nCG = 247), aged M = 76.78 years (SD = 6.35). For the composite endpoint, neither a significant difference between IG and CG (p = .88) nor a group-time interaction (p = .52; p = .88) could be observed. Participants in both groups showed a significant decline on the primary outcome between T0 and T2 (p < .001). Post hoc analyses revealed a decline in both functional health (p < .001) and depressive symptoms (p = .02). Both groups did not differ in their evaluation of their health care situation (p = .93), HRQL (p = .44) or LS (p = .32). Relevant confounding variables were female gender and multimorbidity. Conclusion Supporting patients’ self-management in coordinating their individual care network through LoChro-Care did not result in any significant effect on the primary and secondary outcomes. A decline of functional health and depressive symptoms was observed among all participants. Potential future intervention adaptations are discussed, such as a more active case management through direct referral to (in-)formal support, an earlier treatment initiation, and the consideration of specific sociodemographic factors in care management planning. Trial registration German Clinical Trials Register (DRKS): DRKS00013904 (02.02.2018), https://drks.de/search/de/trial/DRKS00013904

Background Older patients are at an increased risk of hospitalization, negatively affecting their health and quality of life. Such patients also experience a lack of physical activity during their inpatient stay, as well as being at increased risk of delirium and inappropriate prescribing. These risk factors can accumulate, promoting a degree of morbidity and the development of cognitive impairment. Methods Through the ReduRisk-program, patients at risk of functional impairment, immobility, falls, delirium or re-hospitalization shortly after hospital discharge, will be identified via risk-screening. These patients will receive an individually tailored, multicomponent and risk-adjusted prevention program. The trial will compare the effectiveness of the ReduRisk-program against usual care in a stepped-wedge-design, with quarterly cluster randomization of six university hospital departments into intervention and control groups. 612 older adults aged 70 years or more are being recruited. Patients in the intervention cluster (n = 357) will receive the ReduRisk-program, comprising risk-adjusted delirium management, structured mobility training and digitally supported planning of post-inpatient care, including polypharmacy management. This study will evaluate the impact of the ReduRisk-program on the primary outcomes of activities of daily living and mobility, and the secondary outcomes of delirium, cognition, falls, grip strength, health-related quality of life, potentially inappropriate prescribing, health care costs and re-hospitalizations. Assessments will be conducted at inpatient admission (t0), at discharge (t1) and at six months post-discharge (t2). In the six-month period following discharge, a health-economic evaluation will be carried out based on routine health insurance data (t3). Discussion Despite the importance of multicomponent, risk-specific approaches to managing older patients, guidelines on their effectiveness are lacking. This trial will seek to provide evidence for the effectiveness of a multicomponent, risk-adjusted prevention program for older patients at risk of functional impairment, immobility, falls, delirium and re-hospitalization. Positive study results would support efforts to improve multicomponent prevention and the management of older patients. Trial registration German Clinical Trials Register, DRKS00025594, date of registration: 09/08/2021.