The Born−Oppenheimer (BO) approximation is fundamental to computational chemistry because it drastically simplifies the time-independent Schrödinger equation, making calculations for molecular systems computationally feasible. Accurate determination of the diagonal Born−Oppenheimer correction (DBOC) is essential for achieving benchmark accuracy in high-level thermochemical applications. Here, we establish the DBOC200HC database, consisting of 200 structurally diverse hydrocarbons with up to 18 carbon atoms (e.g., triamantane (C₁₈H₂₄)), including aliphatic, aromatic, antiaromatic, cyclic, noncyclic, and caged systems. Reference DBOCs are determined near the coupled-cluster singles and doubles complete basis set limit (CCSD/CBS) using additivity schemes based on HF/cc-pVQZ and CCSD/cc-pVnZ (n = D, T) calculations. Given the computational expense associated with CCSD/CBS calculations for large hydrocarbons, it is important to develop reliable yet computationally economical approximations. Several such approaches are assessed using the DBOC200HC database. While scaled Hartree−Fock methods offer limited improvement, methods incorporating first-order Møller−Plesset perturbation theory (MP1) perform significantly better. Specifically, calculating the DBOC at the MP1/cc-pVDZ level of theory and scaling the MP1 correlation component (ΔE_DBOC ^MP1 = E_DBOC ^MP1 − E_DBOC ^HF ) by an empirical factor of 1.5447 yields the best balance between accuracy (RMSD = 0.026 kJ/mol) and computational cost (practically the same cost as HF/cc-pVDZ). This exceptionally low RMSD suggests that highly accurate DBOCs for use in high-level thermochemical protocols can be obtained via the scaled MP1 approach, without resorting to computationally more demanding levels of theory such as MP2 or CCSD. To validate our results, we further test the empirical methods optimized over the DBOC200HC database on an independent database of 12 larger hydrocarbons, including systems like dodecahedrane(CH)₂₀.

Objectives We aimed to explore sex-specific differences in resting blood pressure (BP) reduction and associated cardiovascular adaptations following isometric exercise training (IET).

Methods 100 sedentary adults with normal to high-normal systolic BP volunteered for the study. Participants either performed home-based lower-body IET in the form of a wall squat three times a week for 4 weeks (each session comprised 4×2min bouts) or were allocated to the control group. Cardiovascular variables, including BP, cardiac output, total peripheral resistance, stroke volume and heart rate variability (HRV), were measured at rest preintervention and postintervention.

Results Following 4 weeks of IET, there were no significant differences in resting systolic BP and diastolic BP between females (122.1±6.9 and 80.0±8.3mm Hg) and males (119.6±7.2 and 77.4±8.6mm Hg). However, female participants had a greater cardiac autonomic response following training, evidenced by a lower lowfrequency to high-frequency HRV ratio (F: 1.38±1.27 and M: 2.1±1.5, p=0.004) and decreased and elevated lowfrequency normalised units (F: 50.3%±16.2%and M: 60.9%±16.9%, p=0.015) and high-frequency normalised units (F: 49.7%±16.2%and M: 39.1%±16.9%, p=0.015), respectively.

Conclusions While resting BP reductions were comparable between female and male participants, there was a greater autonomic response and a higher incidence of clinically important BP reductions in females, which could indicate a greater cardioprotective effect following IET. These findings highlight the importance of considering sex differences in the prescription and evaluation of exercise interventions for hypertension management.

Aim: To explore the experiences of new graduate registered nurses in caring for the deteriorating patient in rural areas.

Background: New graduate registered nurses often feel unprepared to care for the deteriorating patient. Whilst literature has recognised new graduate registered nurses working within metropolitan areas feel ill-equipped to care for deteriorating patients, there is a paucity of literature focused on experiences within the rural context.

Design: Qualitative, descriptive phenomenological approach.

Methods: In-depth interviews were undertaken with 7 participants in rural Eastern Australia with collected data being subject to thematic analysis.

Results: Three themes were identified that shares the lived experiences of the participants as they transitioned into the rural team: First encounters—Transition to the rural team; Practice support for managing deterioration; and The road to confidence.

Conclusion: New graduate registered nurses are unprepared to care for the deteriorating patient in rural areas. Practice support and barriers to ongoing education are influential on their experience with findings from this study supporting focused rural healthcare preparation from tertiary education providers, plus structured practice support from senior rural nurses and health facility orientation programs. Preparation should include the use of digital technologies and escalation and management of the deteriorating patient alongside rural policies and procedures to enhance patient safety and support new graduate rural nurses.

Implications for the Profession and/or Patient Care: The findings have implications for tertiary undergraduate nursing education and those supporting New Graduate Registered Nurses in their transition to practice in rural areas. Enhancement of new graduate nurses' skills and abilities in recognition and responding to patient deterioration through both technological and personnel support will enhance patient safety within rural health care.

Reporting Method: Standards for Reporting Qualitative Research (SRQR).

Patient or Public Contribution: 7 participants were involved in the study.