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Spin-crossover complexes, valued for their bistability, are extensively studied due to their numerous potential applications. A primary challenge in this molecular class is to identify effective methods to adjust the spin-transition temperature, which frequently falls outside the desired temperature range. This typically necessitates intricate chemical design and synthesis or the use of stimuli such as light or pressure, each introducing its own set of challenges for integrating these molecules into end-user applications. In this work, we aim to address this challenge using an oriented external electric field (OEEF) as one stimulus to modulate the spin-transition temperatures. For this purpose, we have employed both periodic and non-periodic calculations on three well-characterised Fe(II) SCO complexes, namely [Fe(phen)2(NCS)2] (1, phen = 1,10-phenanthroline), [Fe(bt)2(NCS)2] (2, bt = 2,2'-bi-2-thiazoline) and [Fe(py)2phen(NCS)2] (3, py = pyridine) possessing a similar structural motif of {FeN4N'2}. To begin with, DFT calculations employing the TPSSh functional were performed on complexes 1 to 3, and the estimated low-spin (LS) and high-spin (HS) gaps are 24.6, 15.3 and 15.4 kJ mol-1, and these are in the range expected for Fe(II) SCO complexes. In the next step, an OEEF was applied in the molecule along the pseudo-C2 axis that bisects two coordinated -NCS groups. Application of an OEEF was found to increase the Fe-ligand bond length and found to affect the spin-transition at the particular applied OEEF. While the HS state of 1 becomes the ground state at an applied field of 0.514 V Å-1, the LS state lies at a higher energy of 1.3 kJ mol-1. Similarly, complexes 2 and 3 also show the HS ground state at an applied field of 0.514 V Å-1, where the LS state stays at higher energies of 6.13 and 11.62 kJ mol-1, respectively. It is found that the overall change in enthalpy (HHL) and entropy (SHL) for the spin transition in the presence of OEEFs decreases upon increasing the strength of the applied field. The computed spin-transition temperature (T1/2) using DFT was found to be in close agreement with the experimentally reported values. It is estimated that on increasing the strength of the applied electric field, the T1/2 increases significantly. While the DFT computed T1/2 values for the optimised geometry of 1, 2 and 3 were found to be 134.6 K, 159.9 K and 111.4 K respectively, at the applied field of 0.6425 V Å-1 T1/2 increases up to 187.3 K, 211.0 K and 184.4 K respectively, unveiling an hitherto unknown strategy to tune the T1/2 values. A limited benchmarking was performed with five additional exchange-correlation functionals: PBE, BLYP, B3LYP*, B3LYP, and PBE0. These functionals were found to be unsuitable for predicting the correct SCO behaviour for complex 2, and their behaviour under various electric fields did not improve. This emphasises the importance of choosing the correct functional at zero OEEF prior to testing them under various electric fields. Furthermore, calculations were performed with complex 1 adsorbed on the Au(111) surface. The formation of an Au-S bond during adsorption significantly stabilises the low-spin (LS) state, hindering the observation of spin-crossover (SCO) behaviour. Nonetheless, the application of an OEEF reduces this gap and brings the T1/2 value closer to the desired temperature. This offers a novel postfabrication strategy for attaining SCO properties at the interface. [ABSTRACT FROM AUTHOR]

Antibiotic stewardship programs (ASPs) play a crucial role in optimizing antibiotic use and combating microbial resistance, particularly in emergency care settings. This prospective study, conducted at a tertiary care hospital in Central India, aimed to evaluate the impact of ASPs on various clinical outcomes, including biochemical markers, microbial resistance patterns, and overall infection management. Over a 12-month period, the study compared infection-related data from patients before and after the implementation of an ASP. Key biochemical markers, such as C-reactive protein (CRP) and procalcitonin (PCT), were assessed to determine changes in inflammation and infection severity. Microbial cultures were analyzed to evaluate shifts in resistance rates among common pathogens. Additionally, antibiotic usage patterns were monitored to identify changes in prescribing practices, while the length of hospital stay was evaluated to assess overall patient outcomes. The results indicated a significant reduction in CRP and PCT levels post-ASP implementation, suggesting improved infection control and more targeted antibiotic therapy. Notable decreases in resistance rates for pathogens such as Escherichia coli and Staphylococcus aureus were observed, reflecting the successful impact of ASPs on reducing microbial resistance. Changes in antibiotic usage patterns showed a decrease in the use of broad-spectrum antibiotics, including cephalosporins and fluoroquinolones, in favor of more appropriate antibiotic choices. Furthermore, the average length of hospital stay was significantly reduced, highlighting the efficiency gains associated with ASPs. These findings underscore the effectiveness of ASPs in optimizing emergency care by improving infection management, reducing resistance rates, and promoting more judicious use of antibiotics. The study's results are consistent with recent literature, reinforcing the value of ASPs in various healthcare settings. The research supports the continued investment in and evaluation of ASPs to address the growing challenge of antibiotic resistance and enhance patient outcomes. Future studies should focus on validating these findings in broader settings and exploring the long-term effects of ASPs on resistance patterns, patient outcomes, and economic implications. [ABSTRACT FROM AUTHOR]

The present study is an integrated approach of experimental and simulation processes to investigate the influences of the flushing on the wear, textural feature, heat dissipation, tool-tip temperature, and elemental contents of the electrical discharge machining-tool. The general heat transfer equation in cylindrical coordinates is used to explain the thermal phenomenon through the tool, where the boundary conditions are influenced by convective interactions and dimensionless numbers. The inter-electrode flushing is considered a micro-channel flow, and the used model is conceptualized from "Hazen–Poiseuille observation." It is observed that the adopted model has a prediction error of 8.503% and can accurately explain the thermal consequences of the process. The study reveals that tool wear is influenced by flushing velocity and flushing pressure. The tool-tip temperature reduces with the Reynolds number, and effectual expelling of the debris can be ensued with a flushing of a higher Reynolds number (Re). However, the increment of Re beyond 4500 provides rapid heat dissipation, which produces extensive residual stress and creates cracks on the surface. [ABSTRACT FROM AUTHOR]

This article speculated the wear and frictional performance of treated micro coir filler reinforced polymer composite. The surface of the coir filler is modified by the alkali treatment and the composite is prepared with a variation of coir filler reinforcement. The investigation of wear test is steered under dry sliding contact, wet and heated contact state using the pin-on-disk multi-tribometer counter to a stainless steel disc. Experiments 1were conducted considering three different parameters, namely, different normal load (5–40 N), sliding velocity 100 cm/s, and sliding distance (0–2000 m). The results showed that the wear behavior of coir filler-reinforced composite is highly dependent on operating parameters and filler reinforcement. The specific wear rate is lesser in wet contact conditions compared to dry and heated contact conditions. Moreover, lower coir filler loading presented enhanced wear presentation related to the higher filler loading composite. From microscopic images, some micro and macro cracks, debonding, and plastic deformation are witnessed on the worn surfaces of the composite. [ABSTRACT FROM AUTHOR]

The current research project is dedicated to tackling the issue of fiber alignment and composite material delamination. Alkali treatment is performed to enhance the bamboo filler reinforced composite's mechanical performance as well as interfacial bonding strength. The hybrid composite is developed with varied bamboo powder content from 2.5 to 12.5 wt% and graphite nanoplatelets (GN) are reinforced in the polymer matrix. The hybrid composite is manufactured with bamboo powder approximately 65 μm sized and GN for electrical and electronics packaging, heat sink, conductive paste, light back cover for thermal management, automobile parts, and packaging goods. The developed material is investigated experimentally through the tensile test, modulus of elasticity, storage modulus, thermal conductivity, corrosion and tribological analysis. Results revealed that 5 and 7.5 wt% bamboo filler with 1 wt% GN gives the best property among others. [ABSTRACT FROM AUTHOR]