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2.
Eur J Hosp Pharm ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604616

RESUMO

OBJECTIVE: From 1995, the European Association of Hospital Pharmacists (EAHP) has regularly investigated the progress of the hospital pharmacy profession in Europe, and identified key barriers and drivers of this. The most recent 'Investigation of the Hospital Pharmacy Profession in Europe' was conducted from November 2022 to March 2023. METHODS: The online questionnaire was sent to all hospital pharmacies in EAHP member countries. The investigation was drafted using the same questions as the 2015 baseline survey. Where possible and relevant, responses were compared with the data from previous surveys that monitored the implementation of the EAHP statements. Keele University, Centre for Medicines Optimisation, School of Pharmacy and Bioengineering, UK analysed the data. RESULTS: The overall number of responses was 653, with a better response rate of 19% compared with 14% in 2018 statements survey. The findings indicated that participating hospital pharmacies have similar characteristics to previous surveys. Section 1 (Introductory statements and governance), section 2 (Selection, procurement and distribution), section 3 (Production and compounding), section 5 (Patient safety and quality assurance) questions were generally answered positively, with results ranging from 52% to 90%. However, results for section 4 (Clinical pharmacy services) returned lower levels of positivity, with responses from 8 of the 15 questions being less than 60%. When asked what is preventing hospital pharmacists from achieving implementation of these activities, most answers were limited capacity, not considered to be a priority by managers, or other healthcare professionals do this. The last section focused on self-assessment and action planning, with fewer than 50% of positive responses; COVID-19 preparedness and vaccines with mixed positive and negative responses. Furthermore, implementation of the falsified medicines directive impacted the medication handling processes in 50% or more of the answers. Regarding sustainability, the majority (59%) of respondents felt a greater focus should be on sustainability from an organisational or management perspective. CONCLUSION: Results offer valuable insights into the hospital pharmacy profession throughout Europe. While there have been improvements in certain areas, challenges remain, particularly in implementing clinical pharmacy services. The findings provide a foundation for further dialogue, advocacy, and strategic planning to advance the role of hospital pharmacists and enhance patient care in Europe's healthcare systems.

3.
Nat Commun ; 15(1): 2249, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480695

RESUMO

Icing of seawater droplets is capable of causing catastrophic damage to vessels, buildings, and human life, yet it also holds great potential for enhancing applications such as droplet-based freeze desalination and anti-icing of sea sprays. While large-scale sea ice growth has been investigated for decades, the icing features of small salty droplets remain poorly understood. Here, we demonstrate that salty droplet icing is governed by salt rejection-accompanied ice crystal growth, resulting in freezing dynamics different from pure water. Aided by the observation of brine films emerging on top of frozen salty droplets, we propose a universal definition of freezing duration to quantify the icing rate of droplets having varying salt concentrations. Furthermore, we show that the morphology of frozen salty droplets is governed by ice crystals that sprout from the bottom of the brine film. These crystals grow until they pierce the free interface, which we term ice sprouting. We reveal that ice sprouting is controlled by condensation at the brine film free interface, a mechanism validated through molecular dynamics simulations. Our findings shed light on the distinct physics that govern salty droplet icing, knowledge that is essential for the development of related technologies.

4.
Eur J Hosp Pharm ; 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38307707

RESUMO

AIMS AND OBJECTIVE: The aim of the European Association of Hospital Pharmacists (EAHP)'s 2023 shortages survey was to collect data on causes and mitigation strategies of shortages of medicines and medical devices and their impact on patient care. The survey targeted hospital pharmacists (HPs), physicians (PHYs), nurses (NRS) and other healthcare professionals (OHCPs). A separate set of questions addressed patients (PTNs). METHODS: A 49-question survey was carried out by a team at EAHP, collecting information from European HPs, PTNs, NRS, PHYs and OTHCs on shortages of medicines and medical devices in their respective countries. The survey ran from 27 February to 19 May 2023. The results were analysed by EAHP. RESULTS: There were 1497 HP responses to the 2023 survey. While 95% (n=1429) of HPs and 86% (n=127) of OHCPs consider medicine shortages an ongoing problem, 84% (n=48) of PHYs and 68% (n=15) of NRS also agreed. Shortages of active pharmaceutical ingredients (77%, n=1148), manufacturing (67%, n=1007) and supply chain problems (50%, n=752) are major causes of shortages according to HPs as well as NRS and OHCPs; PHYs (49%, n=18) consider pricing to be the driver. More than 60% (n=765) of HPs, 55% (n=11) of NRS, 57% (n=30) of PHYs and 46% (n=56) of OHCPs experienced shortages of medical devices in 2022. Antimicrobials were most affected, according to all respondent groups, followed by analgesics, anaesthetics, cardiovascular and paediatric medicines. HPs (59%, n=269), NRS (57%, n=4), OHCPs (56%, n=37) and PHYs (54%, n=14) consider delays in care as the main consequence of medication shortages. CONCLUSIONS: Shortages of medicines and medical devices affect healthcare services and patient care. Increased transparency and access to information regarding ongoing and emerging shortages as well as better preparedness of healthcare professionals is crucial to their effective management.

5.
Adv Colloid Interface Sci ; 324: 103075, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219342

RESUMO

A consensus was built in the first half of the 20th century, which was further debated more than 3 decades ago, that the wettability and condensation mechanisms on smooth solid surfaces are modified by the adsorption of organic contaminants present in the environment. Recently, disagreement has formed about this topic once again, as many researchers have overlooked contamination due to its difficulty to eliminate. For example, the intrinsic wettability of rare earth oxides has been reported to be hydrophobic and non-wetting to water. These materials were subsequently shown to display dropwise condensation with steam. Nonetheless, follow on research has demonstrated that the intrinsic wettability of rare earth oxides is hydrophilic and wetting to water, and that a transition to hydrophobicity occurs in a matter of hours-to-days as a consequence of the adsorption of volatile organic compounds from the ambient environment. The adsorption mechanisms, kinetics, and selectivity, of these volatile organic compounds are empirically known to be functions of the substrate material and structure. However, these mechanisms, which govern the surface wettability, remain poorly understood. In this contribution, we introduce current research demonstrating the different intrinsic wettability of metals, rare earth oxides, and other smooth materials, showing that they are intrinsically hydrophilic. Then we provide details on research focusing on the transition from wetting (hydrophilicity) to non-wetting (hydrophobicity) on somooth surfaces due to adsorption of volatile organic compounds. A state-of-the-art figure of merit mapping the wettability of different smooth solid surfaces to ambient exposure as a function of the surface carbon content has also been developed. In addition, we analyse recent works that address these wetting transitions so to shed light on how such processes affect droplet pinning and lateral adhesion. We then conclude with objective perspectives about research on wetting to non-wetting transitions on smooth solid surfaces in an attempt to raise awareness regarding this surface contamination phenomenon within the engineering, interfacial science, and physical chemistry domains.

6.
Langmuir ; 39(51): 18909-18922, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38078869

RESUMO

Jumping droplet condensation, whereby microdroplets (ca. 1-100 µm) coalescing on suitably designed superhydrophobic surfaces jump away from the surface, has recently been shown to have a 10× heat transfer enhancement compared to filmwise condensing surfaces. However, accurate measurements of the condensation heat flux remain a challenge due to the need for low supersaturations (<1.1) to avoid flooding. The low corresponding heat fluxes (<5 W/cm2) can result in temperature noise that exceeds the resolution of the measurement devices. Furthermore, difficulties in electro-thermal measurements such as droplet and surface electrostatic charge arise in applications where direct access to the condensing surface, such as in isolated chambers and small integrated devices, is not possible. Here, we present an optical technique that can determine the experimental electro-thermal parameters of the jumping droplet condensation process with high fidelity through the analysis of jumping droplet trajectories. To measure the heat flux, we observed the experimental trajectories of condensate droplets on superhydrophobic nanostructures and simultaneously matched them in space and time with simulated trajectories using the droplet dynamic equations of motion. Two independent approaches yielded mean heat fluxes of approximately 0.13 W/cm2 with standard deviations ranging from 0.047 to 0.095 W/cm2, a 79% reduction in error when compared with classical energy balance-based heat flux measurements. In addition, we analyzed the trajectories of electrostatically interacting droplets during flight and fitted the simulated and experimental results to achieve spatial and temporal agreement. The effect of image charges on a jumping droplet as it approaches the surface was analyzed, and the observed acceleration has been numerically quantified. Our work presents a sensing methodology of electro-thermal parameters governing jumping droplet condensation.

9.
Nat Commun ; 14(1): 4902, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580321

RESUMO

Seventy percent of global electricity is generated by steam-cycle power plants. A hydrophobic condenser surface within these plants could boost overall cycle efficiency by 2%. In 2022, this enhancement equates to an additional electrical power generation of 1000 TWh annually, or 83% of the global solar electricity production. Furthermore, this efficiency increase reduces CO2 emissions by 460 million tons /year with a decreased use of 2 trillion gallons of cooling water per year. However, the main challenge with hydrophobic surfaces is their poor durability. Here, we show that solid microscale-thick fluorinated diamond-like carbon (F-DLC) possesses mechanical and thermal properties that ensure durability in moist, abrasive, and thermally harsh conditions. The F-DLC coating achieves this without relying on atmospheric interactions, infused lubricants, self-healing strategies, or sacrificial surface designs. Through tailored substrate adhesion and multilayer deposition, we develop a pinhole-free F-DLC coating with low surface energy and comparable Young's modulus to metals. In a three-year steam condensation experiment, the F-DLC coating maintains hydrophobicity, resulting in sustained and improved dropwise condensation on multiple metallic substrates. Our findings provide a promising solution to hydrophobic material fragility and can enhance the sustainability of renewable and non-renewable energy sources.

10.
Healthcare (Basel) ; 11(13)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37444672

RESUMO

The introduction of the National Surveillance Centre (NSC) has improved the efficiency and effectiveness of managing medicines availability within the public healthcare system in South Africa. However, at present, there is limited data regarding the perceptions among users of the NSC and challenges that need addressing. A descriptive quantitative study was performed among all registered active NSC users between August and November 2022. Overall, 114/169 users responded to a custom-developed, self-administered questionnaire (67.5% response rate). Most respondents used the Stock Visibility System (SVS) National Department of Health (NDoH) (66.7% for medicines and 51.8% for personal protective equipment (PPE) or SVS COVID-19 (64.9% for COVID-19 vaccines) or RxSolution (57.0% manual report or 42.1% application programming interface (API)) for reporting medicines, PPE, and COVID-19 vaccines to the NSC and were confident in the accuracy of the reported data. Most respondents focused on both medicines availability and reporting compliance when accessing the NSC, with the integrated medicines availability dashboard and the COVID-19 vaccine dashboard being the most popular. The respondents believed the NSC allowed ease of access to data and improved data quality to better monitor medicines availability and use. Identified areas for improvement included improving internet connectivity, retraining some users, standardising the dashboards, adding more data points and reports, and expanding user adoption by increasing licence limits. Overall, this study found that the NSC in South Africa provides an effective solution for monitoring and improving medicines availability.

11.
Nano Lett ; 23(9): 3669-3677, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37079783

RESUMO

Passive daytime radiative cooling (PDRC) has the potential to reduce energy demand and mitigate global warming. However, surface contamination from dust and bacterial buildup limits practical PDRC applications. Here, we develop a hierarchically patterned nanoporous composite (HPNC) using a facile template-molding fabrication method to integrate PDRC materials with self-cleaning and antibacterial functions. The HPNC design decouples multifunctional control into different characteristic length scales that can be optimized simultaneously. The nanoporous polymer matrix embedded with tunable fillers enables 7.8 and 4.4 °C temperature reduction for outdoor personal and building cooling, respectively, under intense solar irradiance. Meanwhile, a microscale pillar array pattern integrated into the HPNC enables superhydrophobicity with self-cleaning and antisoiling functions to mitigate surface contamination. Moreover, the surface coating of photocatalytic agents can generate photoinduced antibacterial effects. The scalable fabrication and multifunctional capabilities of our HPNC design offer a promising solution for practical PDRC applications with minimal maintenance needs.

12.
Artigo em Inglês | MEDLINE | ID: mdl-36881487

RESUMO

Juxtaposing hydrophilicity and hydrophobicity on the same surface, known as hybrid surface engineering, can enhance phase-change heat transfer. However, controlling hydrophilicity on hybrid surfaces in a scalable fashion is a challenge, limiting their application. Here, using widely available metal meshes with variable dimensions and by controlling the patterning pressure, we scalably fabricate hybrid surfaces having spot and gridlike patterns using stamping. Using fog harvesting in a controlled chamber, we show that optimized hybrid surfaces have a ∼37% higher fog harvesting rate when compared to homogeneous superhydrophobic surfaces. Furthermore, condensation frosting experiments reveal that, on grid-patterned hybrid surfaces, frost propagates at ∼160% higher velocity and provides ∼20% less frost coverage when compared to homogeneous superhydrophobic surfaces. During defrost, our hybrid surfaces retain more water when compared to superhydrophobic surfaces due to the presence of hydrophilic patterns and melt water pinning. We adapt our fabrication technique to roll-to-roll patterning, demonstrating wettability contrast on round metallic geometries via atmospheric water vapor condensation. This work provides guidelines for the rapid, substrate-independent, and scalable fabrication of hybrid wettability surfaces for a wide variety of applications.

13.
Nanoscale Adv ; 5(5): 1232-1270, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36866258

RESUMO

Liquid-vapor phase change phenomena such as boiling and condensation are processes widely implemented in industrial systems such as power plants, refrigeration and air conditioning systems, desalination plants, water processing installations and thermal management devices due to their enhanced heat transfer capability when compared to single-phase processes. The last decade has seen significant advances in the development and application of micro and nanostructured surfaces to enhance phase change heat transfer. Phase change heat transfer enhancement mechanisms on micro and nanostructures are significantly different from those on conventional surfaces. In this review, we provide a comprehensive summary of the effects of micro and nanostructure morphology and surface chemistry on phase change phenomena. Our review elucidates how various rational designs of micro and nanostructures can be utilized to increase heat flux and heat transfer coefficient in the case of both boiling and condensation at different environmental conditions by manipulating surface wetting and nucleation rate. We also discuss phase change heat transfer performance of liquids having higher surface tension such as water and lower surface tension liquids such as dielectric fluids, hydrocarbons and refrigerants. We discuss the effects of micro/nanostructures on boiling and condensation in both external quiescent and internal flow conditions. The review also outlines limitations of micro/nanostructures and discusses the rational development of structures to mitigate these limitations. We end the review by summarizing recent machine learning approaches for predicting heat transfer performance of micro and nanostructured surfaces in boiling and condensation applications.

14.
ACS Appl Mater Interfaces ; 15(10): 13711-13723, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36862945

RESUMO

Rapid implementation of renewable energy technologies has exacerbated the potential for economic loss and safety concerns caused by ice and frost accretion, which occurs on the surfaces of wind turbine blades, photovoltaic panels, and residential and electric vehicle air-source heat pumps. The past decade has seen advances in surface chemistry and micro- and nanostructures that can promote passive antifrosting and enhance defrosting. However, the durability of these surfaces remains the major obstacle preventing real-life applications, with degradation mechanisms remaining poorly understood. Here, we conducted durability tests on antifrosting surfaces, including superhydrophobic, hydrophobic, superhydrophilic, and slippery liquid-infused surfaces. For superhydrophobic surfaces, we demonstrate durability with progressive degradation for up to 1000 cycles of atmospheric frosting-defrosting and month-long outdoor exposure tests. We show that progressive degradation, as reflected by increased condensate retention and reduced droplet shedding, results from molecular-level degradation of the low-surface-energy self-assembled monolayer (SAM). The degradation of the SAM leads to local high-surface-energy defects, which further deteriorate the surface by promoting accumulation of atmospheric particulate matter during cyclic condensation, frosting, and melt drying. Furthermore, cyclic frosting and defrost tests demonstrate the durability and degradation mechanisms of other surfaces to show, for example, the loss of water affinity of superhydrophilic surfaces after 22 days due to atmospheric volatile organic compound (VOC) adsorption and significant lubricant drainage for lubricant-infused surfaces after 100 cycles. Our work reveals the degradation mechanism of functional surfaces during exposure to long-term frost-defrost cycling and elucidates guidelines for the development of future surfaces for real-life antifrosting/icing applications.

15.
Nat Commun ; 14(1): 1024, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823288

RESUMO

Soft, wireless physiological sensors that gently adhere to the skin are capable of continuous clinical-grade health monitoring in hospital and/or home settings, of particular value to critically ill infants and other vulnerable patients, but they present risks for injury upon thermal failure. This paper introduces an active materials approach that automatically minimizes such risks, to complement traditional schemes that rely on integrated sensors and electronic control circuits. The strategy exploits thin, flexible bladders that contain small volumes of liquid with boiling points a few degrees above body temperature. When the heat exceeds the safe range, vaporization rapidly forms highly effective, thermally insulating structures and delaminates the device from the skin, thereby eliminating any danger to the skin. Experimental and computational thermomechanical studies and demonstrations in a skin-interfaced mechano-acoustic sensor illustrate the effectiveness of this simple thermal safety system and suggest its applicability to nearly any class of skin-integrated device technology.


Assuntos
Eletrônica , Pele , Humanos , Pele/química , Temperatura Corporal , Temperatura Alta , Software
16.
J Colloid Interface Sci ; 635: 221-230, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36592502

RESUMO

HYPOTHESIS: Droplet spreading governs various daily phenomena and industrial processes. Insights about microdroplet spreading are limited due to experimental difficulties arising from microdroplet manipulation and substrate wettability control. For droplet sizes approaching the capillary length scale, the gravitational force plays an important role in spreading. In contrast, capillary and viscous forces dominate as the droplet size reduces to smaller length scales. We hypothesize that the dynamic spreading behavior of microdroplets whose radius is far lower than the capillary length differs substantially from established and well understood dynamics. EXPERIMENTS: To systematically investigate the spreading dynamics of microdroplets, we develop contact-initiated wetting techniques combined with structuring-independent wettability control to achieve microdroplet (<500 µm) spreading on arbitrary surfaces while eliminating parasitic pinning effects (pining force âˆ¼ 0) and initial impact momentum effects (Weber number âˆ¼ 0). FINDINGS: Our experiments reveal that the capillary-driven initial spreading of microdroplets is shorter, with significantly reduced oscillation dampening, when compared to millimeter-scale droplets. Furthermore, spreading along with capillary wave propagation results in coupling between the spreading velocity and dynamic contact angle at the contact line. These findings, along with our proposed microdroplet manipulation platform, may find application in microscale heat transfer, advanced manufacturing, and aerosol transmission studies.

17.
Proc Natl Acad Sci U S A ; 120(6): e2217828120, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36716364

RESUMO

Thermal sensations contribute to our ability to perceive and explore the physical world. Reproducing these sensations in a spatiotemporally programmable manner through wireless computer control could enhance virtual experiences beyond those supported by video, audio and, increasingly, haptic inputs. Flexible, lightweight and thin devices that deliver patterns of thermal stimulation across large areas of the skin at any location of the body are of great interest in this context. Applications range from those in gaming and remote socioemotional communications, to medical therapies and physical rehabilitation. Here, we present a set of ideas that form the foundations of a skin-integrated technology for power-efficient generation of thermal sensations across the skin, with real-time, closed-loop control. The systems exploit passive cooling mechanisms, actively switchable thermal barrier interfaces, thin resistive heaters and flexible electronics configured in a pixelated layout with wireless interfaces to portable devices, the internet and cloud data infrastructure. Systematic experimental studies and simulation results explore the essential mechanisms and guide the selection of optimized choices in design. Demonstration examples with human subjects feature active thermoregulation, virtual social interactions, and sensory expansion.


Assuntos
Pele , Realidade Virtual , Humanos , Eletrônica , Sensação Térmica , Comunicação
18.
Langmuir ; 39(1): 367-376, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36548905

RESUMO

Vapor condensation is widely used in industrial systems due to its effective heat and mass transfer when compared to single-phase thermal transport. In particular, dropwise condensation can significantly enhance heat transfer performance due to rapid droplet shedding and promotion of additional nucleation sites for vapor condensation. Recently, lubricant-infused surfaces (LISs) composed of superhydrophobic structures infused with a low surface tension lubricant have been shown to effectively promote dropwise condensation of a variety of fluids by forming chemically and topographically homogeneous low-surface-energy surfaces. However, depletion of the infused lubricant remains a critical limitation to developing durable LISs which can sustain prolonged dropwise condensation. Moreover, the observed degradation is difficult to detect especially during active condensation on the surface. Here, we introduce an optical measurement technique to quantify in situ and in operando lubricant drainage from LISs. The optical method allows for non-invasive, instantaneous, and accurate prediction of the lifespan of LISs. The method implements the analysis of sample transient transparency, with depletion leading to exposure of the structure and increased light scattering. Our work demonstrates the logarithmic relation between the amount of the lubricant remaining in the LIS and the optical transmittance of the LIS, validating our unique technique for estimating the durability of LISs.

19.
ACS Appl Mater Interfaces ; 15(1): 2429-2436, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36563177

RESUMO

The surface energy of graphene and its chemical derivatives governs fundamental interfacial interactions like molecular assembly, wetting, and doping. However, quantifying the surface energy of supported two-dimensional (2D) materials, such as graphene, is difficult because (1) they are so thin that electrostatic interactions emanating from the underlying substrate are not completely screened, (2) the contribution from the monolayer is sensitive to its exact chemical state, and (3) the adsorption of airborne contaminants, as well as contaminants introduced during transfer processing, screens the electrostatic interactions from the monolayer and underlying substrate, changing the determined surface energy. Here, we determine the polar and dispersive surface energy of bare, fluorinated, and hydrogenated graphene through contact angle measurements with water and diiodomethane. We accounted for many contributing factors, including substrate surface energies and combating adsorption of airborne contaminants. Hydrogenating graphene raises its polar surface energy with little effect on its dispersive surface energy. Fluorinating graphene lowers its dispersive surface energy with a substrate-dependent effect on its polar surface energy. These results unravel how changing the chemical structure of graphene modifies its surface energy, with applications for hybrid nanomaterials, bioadhesion, biosensing, and thin-film assembly.

20.
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