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1.
Nurs Crit Care ; 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38924665

ABSTRACT

BACKGROUND: The surge in critically ill COVID-19 patients caused a shortage of intensive care unit (ICU) beds. Some hospitals temporarily transformed general wards into ICUs to meet this pressing health care demand. AIM: This study aims to evaluate and analyse the risk factors in temporary ICU from the perspective of nurses. By identifying these factors, the goal is to provide actionable insights and recommendations for effectively establishing and managing temporary ICUs in similar crisis scenarios in the future. STUDY DESIGN: The study was conducted in China within a public hospital. Specifically, it focused on examining 62 nurses working in a temporary ICU that was converted from an infectious disease ward. The research utilized the Hazard Vulnerability Analysis (HVA) scoring method to identify potential threats, evaluate their probability, estimate their impact on specific organizations or regions and calculate the relative risk associated with such occurrences. RESULTS: Staff demonstrated the highest risk percentage (32.74%), with Stuff (16.11%), Space (15.19%) and System (11.30%) following suit. The most critical risk factors included insufficient knowledge and decision-making competence in critical care (56.14%), lacking decision-making abilities and skills in renal replacement therapy care (55.37%), inadequate decision-making capacity and relevant skills in respiratory support care (50.64%), limited decision-making capability in circulatory support care (45.73%) and unfamiliarity with work procedures or systems (42.09%). CONCLUSIONS: Urgent implementation of tailored training and support for temporary ICU nurses is paramount. Addressing capability and skill-related issues among these nurses supersedes resource availability, infrastructure, equipment and system considerations. Essential interventions must target challenges encompassing nurses' inability to perform critical treatment techniques autonomously and ensure standardized care. These measures are designed to heighten patient safety and elevate care quality during emergencies. These findings offer a viable avenue to mitigate potential moral distress, anxiety and depression among nurses, particularly those transitioning from non-critical care backgrounds. These nurses swiftly assimilate into temporary ICUs, and the study's insights offer practical guidance to alleviate their specific challenges. RELEVANCE TO CLINICAL PRACTICE: The study on risk factors for converting traditional wards into temporary ICU during the COVID-19 pandemic, especially from the perspective of nurses, provides crucial insights into the challenges and requirements for effectively establishing and managing these emergency settings. The findings highlight several key areas of concern and opportunities for improvement directly related to clinical practice, particularly in situations where there is a rapid need to adapt to increased demands for critical care. By addressing the identified risk factors through enhanced training, support systems, resource management, process improvements and cultivating a culture of adaptability, not only can the quality of care in temporary ICUs be improved, but also can the health care system be better prepared for future emergencies. These actions will help mitigate the risks associated with such conversions, ultimately benefiting patient safety, staff well-being and the overall effectiveness of health care services in crises.

2.
Nat Mater ; 22(8): 943-944, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37524821
3.
Mater Horiz ; 8(5): 1528-1537, 2021 May 01.
Article in English | MEDLINE | ID: mdl-34846461

ABSTRACT

Functional and structural ceramics have become irreplaceable in countless high-tech applications. However, their inherent brittleness tremendously limits the application range and, despite extensive research efforts, particularly short cracks are hard to combat. While local plasticity carried by mobile dislocations allows desirable toughness in metals, high bond strength is widely believed to hinder dislocation-based toughening of ceramics. Here, we demonstrate the possibility to induce and engineer a dislocation microstructure in ceramics that improves the crack tip toughness even though such toughening does not occur naturally after conventional processing. With modern microscopy and simulation techniques, we reveal key ingredients for successful engineering of dislocation-based toughness at ambient temperature. For many ceramics a dislocation-based plastic zone is not impossible due to some intrinsic property (e.g. bond strength) but limited by an engineerable quantity, i.e. the dislocation density. The impact of dislocation density is demonstrated in a surface near region and suggested to be transferrable to bulk ceramics. Unexpected potential in improving mechanical performance of ceramics could be realized with novel synthesis strategies.

4.
Nano Lett ; 21(5): 1962-1967, 2021 Mar 10.
Article in English | MEDLINE | ID: mdl-33596382

ABSTRACT

It was recently found that extremely large plasticity is exhibited in bulk compression of single-crystal ZnS in complete darkness. Such effects are believed to be caused by the interactions between dislocations and photoexcited electrons and/or holes. However, methods for evaluating dislocation behavior in such semiconductors with small dimensions under a particular light condition had not been well established. Here, we propose the "photoindentation" technique to solve this issue by combining nanoscale indentation tests with a fully controlled lighting system. The quantitative data analyses based on this photoindentation approach successfully demonstrate that the first pop-in stress indicating dislocation nucleation near the surface of ZnS clearly increases by light irradiation. Additionally, the room-temperature indentation creep tests show a drastic reduction of the dislocation mobility under light. Our approach demonstrates great potential in understanding the light effects on dislocation nucleation and mobility at the nanoscale, as most advanced technology-related semiconductors are limited in dimensions.

5.
Appl Opt ; 59(10): 3145-3155, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32400597

ABSTRACT

Synchronous measurement of the temperature and deformation fields of large-scale flat specimens is challenging in engineering experiments, especially for high-temperature environment where the non-contact optical method is attempted. To overcome this difficulty of large-scale flat specimens tested at high temperature in the open arc wind tunnel environment, measurement principles and experiments of large-scale flat specimens based on a multi-camera system are proposed using digital image stitching as well as the improved two-color method for temperature measurement. First, the digital image mosaic method is used to process and evaluate the mosaic effect of multi-camera images, the optimal mosaic parameters are selected, and the calculation results are given. Second, a set of images for large-scale flat specimens are deduced based on an improved two-color method of temperature measurement and digital image mosaic algorithms. A stitching algorithm for full-field temperature measurement and calculation results are given. Finally, full-field displacement of the stitched images is calculated by the digital image correlation method. Synchronous measurement of temperature and deformation established in this paper provides guidance for measurement of large-scale flat specimens with high spatial resolution in engineering tests.

6.
Nanotechnology ; 31(4): 045501, 2020 Jan 17.
Article in English | MEDLINE | ID: mdl-31604339

ABSTRACT

Prussian blue (PB) modified nanoporous gold (NPG) electrodes exhibit great potential for improving the detection sensitivity and stability for hydrogen peroxide monitoring. The NPG provides large surface-to-volume ratio as well as diffusion 'highways' to assist the transfer of the ions. In the present work, we optimized the deposition time for NPG fabrication and examine the electrochemical performance of the electrodes. A critical deposition time on the electrochemical performances including linear range, operational stability and sensitivity was experimentally determined. Below and above such a deposition time, two different growth patterns of the microstructures were observed. This transition of deposited structures corresponding to the critical time results in different pathways for electron transfer and ion diffusivity through PB lattice.

7.
Appl Opt ; 58(25): 6966-6974, 2019 Sep 01.
Article in English | MEDLINE | ID: mdl-31503668

ABSTRACT

The high-temperature optical method has been widely used for evaluating structural materials subjected to high temperature. Obtaining high-quality images of a specimen surface in such a harsh environment is detrimental for the accurate measurement of temperature and strain field. However, the high-temperature environment poses many challenges on these measurements, e.g., the large luminance gradient on the sample surface would jeopardize the image quality when using the full-field optical method. In order to overcome this issue, we propose here a simple and effective algorithm to obtain image sequences with serial exposure times. This algorithm incorporates exponentially decreasing exposure times to successfully reduce the disturbance caused by large luminance gradient, as will be shown by the verification on samples tested both in arc wind tunnel and oxy-propane torch flame. In comparison to the images with single exposure time, further experiment carried out on C/SiC sample up to 1100°C shows that image sequences with different exposure times can be effectively obtained by the image fusion technique. The calculation of the deformation and temperature fields using the image sequence method gives more accurate and reasonable results.

8.
Sci Rep ; 8(1): 6684, 2018 Apr 27.
Article in English | MEDLINE | ID: mdl-29703923

ABSTRACT

We use in situ scanning probe microscopy (SPM) to investigate the high temperature oxidation of Ni-based single crystal alloys at the micro-/nanoscale. SiO2 micro-pillar arrays were pre-fabricated on the alloy surface as markers before the oxidation experiment. The SPM measurement of the oxidized surface in the vicinity of SiO2 micro-pillars was conducted real time at temperatures from 300 °C to 800 °C. The full-field evolution of oxide film thickness is quantitatively characterized by using the height of SiO2 micro-pillars as reference. The results reveal the non-uniform oxide growth featuring the nucleation and coalescence of oxide islands on the alloy surface. The outward diffusion of Ni and Co is responsible for the formation and coalescence of first-stage single-grain oxide islands. The second-stage of oxidation involves the formation and coalescence of poly-grain oxide islands.

9.
Appl Opt ; 54(29): 8731-7, 2015 Oct 10.
Article in English | MEDLINE | ID: mdl-26479811

ABSTRACT

In this work, we propose a structural deformation measuring method based on structural feature processing (straight line/edge detection) of the recorded digital images for specimens subjected to a high-temperature environment. Both radiation light and oxidation at high temperatures challenge the optics-based measurements. The images of a rectangular piece of copper specimen are obtained by using a bandpass filtering method at high temperatures, then all the edges are detected by using an edge detection operator, and then a Hough transform is conducted to search the straight edges for the calculation of deformation. Especially, due to the severe oxidation, a special seed strategy is adopted to reduce the oxidation effect and obtain an accurate result. For validation, the structural thermal deformation and the values of coefficients of thermal expansion for the copper specimen are measured and compared with data in the literature. The results reveal that the proposed method is accurate to measure the deformation of the structures at high temperatures.

10.
Appl Opt ; 54(4): 721-7, 2015 Feb 01.
Article in English | MEDLINE | ID: mdl-25967780

ABSTRACT

Thin film stresses in thin film/substrate systems at elevated temperatures affect the reliability and safety of such structures in microelectronic devices. The stresses result from the thermal mismatch strain between the film and substrate. The reflection mode digital gradient sensing (DGS) method, a real-time, full-field optical technique, measures deformations of reflective surface topographies. In this paper, we developed this method to measure topographies and thin film stresses of thin film/substrate systems at elevated temperatures. We calibrated and compensated for the air convection at elevated temperatures, which is a serious problem for optical techniques. We covered the principles for surface topography measurements by the reflection mode DGS method at elevated temperatures and the governing equations to remove the air convection effects. The proposed method is applied to successfully measure the full-field topography and deformation of a NiTi thin film on a silicon substrate at elevated temperatures. The evolution of thin film stresses obtained by extending Stoney's formula implies the "nonuniform" effect the experimental results have shown.

11.
Rev Sci Instrum ; 85(3): 035104, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24689617

ABSTRACT

In this work, we develop an instrument to study the ablation and oxidation process of materials such as C/SiC (carbon fiber reinforced silicon carbide composites) and ultra-high temperature ceramic in extremely high temperature environment. The instrument is integrated with high speed cameras with filtering lens, infrared thermometers and water vapor generator for image capture, temperature measurement, and humid atmosphere, respectively. The ablation process and thermal shock as well as the temperature on both sides of the specimen can be in situ monitored. The results show clearly the dynamic ablation and liquid oxide flowing. In addition, we develop an algorithm for the post-processing of the captured images to obtain the deformation of the specimens, in order to better understand the behavior of the specimen subjected to high temperature.

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