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This paper presents a methodology for accurately incorporating the nonlinearity of boundary conditions (BCs) into the mode shapes, natural frequencies, and dynamic behaviour of analytical beam models. Such models have received renewed interest in recent years as a result of their successful implementation in state-of-the-art multiphysics problems. To address the need for this boundary nonlinearity to be more completely captured in the equations of motion, a nonlinear algebra expansion of the classical linear approach for developing solvability conditions for natural frequencies and mode shapes is presented. The method is applicable to any BC that can be accurately represented in polynomial form, either explicitly or through the application of a Taylor expansion; this is the only assumption made in removing the need for the use of analytical approximations of the dynamics themselves. By reducing the BCs of the beam to a system of polynomials, it is possible to utilise the tensor resultant to develop these solvability conditions analogous to the conditions placed on the matrix determinant in linear, classical cases. The approach is first derived for a general set of nonlinear BCs before being applied to two example systems to investigate the importance of including nonlinear tip behaviour in the BCs to accurately predict the system response. In the first, a theoretical, symmetric system, in which a beam is supported by nonlinear springs, is used to explore both the applicability of the methodology and the improvements it can make to the accuracy of the model. Then, the more practical example of a cantilever beam with repulsive magnetic interaction at the tip is used to more explicitly assess the importance of properly incorporating boundary nonlinearity into multiphysics problems.

Global warming significantly impacts wheat production, altering growing degree days (GDD), a key indicator of heat accumulation essential for crop growth. However, understanding the specific spatiotemporal patterns of GDD and its influence on wheat yields remains limited. This study used 40 years of data from experimental stations in China’s main winter wheat-producing areas to explore the spatiotemporal changes in GDD in the context of climate change and a linear mixed-effects regression model to elucidate the relationship between accumulated GDD at different growth stages and wheat yield. The study found that the accumulated GDD in wheat sowing-to-jointing stage and the accumulated GDD in jointing-to-flowering and flowering-to-maturity stages showed an opposite trend in latitudinal distribution. Over time, the total GDD accumulation increased by an average of 345.23 ℃·d, and the GDD accumulation in the three key growth stages increased by an average of 273.26 ℃·d, 27.21 ℃·d, and 44.77 ℃·d. The accumulated GDD for winter wheat during the sowing-to-jointing stage and flowering-to-maturity stage showed significant increases over 40 years, the GDD during the jointing-to-flowering stage remained relatively stable. The number of days in the growth period during the sowing-to-jointing stage and jointing-to-flowering stage decreased significantly, the number of days during the flowering-to-maturity stage increased significantly. In the northern region, the increase in accumulated GDD in the jointing-to-flowering, and flowering-to-maturity stages was beneficial to the increase in yield. In all regions, the increase in accumulated GDD in the sowing-to-jointing stage causes yield losses, and the losses in the southern region are greater than those in the northern region. For different regions, we have proposed management and breeding plans to make winter wheat better adapted to future changes in GDD. This study provides crucial insights into current challenges and offers a foundation for future research on yield forecasting under varying climate scenarios.

The transdermal drug delivery (TDD) route has gathered considerable attention for its potential to improve therapeutic efficacy while minimizing systemic side effects. Among transdermal technologies, microneedle (MN) devices have proven to be a promising approach that combines the advantages of traditional needle injections and non-invasive topical applications. This review provides a comprehensive analysis of progress in transdermal drug delivery systems (TDDS) via MN from 2000 to 2023, integrating bibliometric analysis and patent landscape to present a multi-faceted perspective on the evolution of this technology. The study identifies key trends, challenges, and opportunities in the research, implementation, and commercialization of MN tools through a systematic examination of scientific literature and an extensive investigation of global patent databases. The study of bibliometric trends reveals the leading experts, organizations, companies, and countries contributing to this field, collaboration networks, and the thematic evolution of research topics. The patent analysis offers insights into innovative trajectories, key players, and geographical distribution of intellectual property. This review resumes the latest advancements in MN devices and provides a strategic outlook that can guide future research directions, promote partnerships, and inform stakeholders involved in the development of TDDS.

BACKGROUND: Sport practice may elevate the risk of cardiovascular events, including sudden cardiac death, in athletes with undiagnosed heart conditions. In Italy, pre-participation screening includes a resting ECG and either the Harvard Step Test (HST) or maximal exercise testing (MET), but the relative efficacy of the latter two tests for detecting arrhythmias and heart conditions remains unclear. METHODS: This study examined 511 paediatric athletes (8–18 years, 76.3% male) without known cardiovascular, renal, or endocrine diseases. All athletes underwent both HST and MET within 30 days. Absolute data and data relative to theoretical peak heart rates, arrhythmias (supraventricular and ventricular) and cardiovascular diagnoses were collected. RESULTS: HST resulted in a lower peak heart rate than MET (181.1 ± 9.8 vs. 187.5 ± 8.1 bpm, p < 0.001), but led to the detection of more supraventricular (18.6% vs. 13.1%, p < 0.001) and ventricular (30.5% vs. 22.7%, p < 0.001) arrhythmias, clustering during recovery (p = 0.014). This pattern was significant in males but not females. Among athletes diagnosed with cardiovascular diseases (22.3%), HST identified more ventricular arrhythmias (26.3% vs. 18.4%, p = 0.05), recovery-phase arrhythmias (20.2% vs. 14.0%, p = 0.035), and polymorphic arrhythmias (6.1% vs. 1.8%, p = 0.025). CONCLUSIONS: HST detects arrhythmias more effectively than MET in young male athletes, especially during recovery. More ventricular arrhythmias were highlighted even in athletes with cardiovascular conditions.

IntroductionResearch suggests that interprofessional education, bringing learners together to learn about, with, and from each other, improves health professions education and can improve health outcomes. Little research has measured outcomes of interprofessional education between midwifery students and obstetrics and gynecology residents. The purpose of this study was to examine self-assessed interprofessional and collaborative competencies among midwifery students and obstetrics and gynecology residents.MethodsBaseline self-assessed interprofessional and collaborative competencies were compared with follow-up measurements to evaluate learners' experiences over an 11-month study period. Participants were midwifery students and obstetrics and gynecology residents who experienced interprofessional learning activities. The Interprofessional Education Collaborative Competency Self-Assessment Survey (IPEC Survey) and Interprofessional Collaborative Competency Attainment Survey (ICCAS) were used.ResultsOf 256 learners at 4 demonstration sites, 223 (87%) completed the baseline, and 121 of 237 eligible learners (51%) completed the follow-up surveys. The IPEC Survey total score (t = 2.31, P = .02) and interaction subscale (t = 2.85, P = .005) and ICCAS score (t = 4.04, P = .001) increased for midwifery students but not obstetrics and gynecology residents on the IPEC Survey (t = 0.32, P = .75) and ICCAS (t = -0.05, P = .96) measures. Midwifery students (87%) and residents (57%) reported improved overall ability to collaborate. Learners responding to 3 open-ended questions valued team-based experiences, including learning how to communicate with each other; appreciated learning each other's education and scope of practice; and recommended skills development including uncommon clinical events, case discussions, and direct clinical care.DiscussionThis study advanced knowledge about interprofessional education between midwifery students and obstetrics and gynecology residents. Midwifery students improved in self-assessed interprofessional and collaborative competencies. Most learners reported better interprofessional collaboration skills and were positive about future interprofessional learning. This evaluation approach is available for other programs implementing or extending interprofessional education.