Identifying Contact Time Required for Secondary Transmission of Clostridioides difficile Infections by Using Real-Time Locating System.

Considering patient room shortages and prevalence of other communicable diseases, reassessing the isolation of patients with Clostridioides difficile infection (CDI) is imperative. We conducted a retrospective study to investigate the secondary CDI transmission rate in a hospital in South Korea, where patients with CDI were not isolated. Using data from a real-time locating system and electronic medical records, we investigated patients who had both direct and indirect contact with CDI index patients. The primary outcome was secondary CDI transmission, identified by whole-genome sequencing. Among 909 direct and 2,711 indirect contact cases, 2 instances of secondary transmission were observed (2 [0.05%] of 3,620 cases), 1 transmission via direct contact and 1 via environmental sources. A low level of direct contact (113 minutes) was required for secondary CDI transmission. Our findings support the adoption of exhaustive standard preventive measures, including environmental decontamination, rather than contact isolation of CDI patients in nonoutbreak settings.

Current Status of Hospitalist Practice and Factors Influencing Job Satisfaction in Korea.

BACKGROUND: Although the roles and responsibilities of hospitalists have grown considerably in recent years, research on the current job status and satisfaction levels of Korean hospitalists is lacking. OBJECTIVE: We investigate the present state of Korean hospitalists and the factors influencing their job satisfaction 6 years after the pilot program's launch. DESIGN: This cross-sectional analysis was based on an online survey conducted from January 30 to February 18, 2023. PARTICIPANTS: Korean hospitalists (N = 303) MAIN MEASURES: The survey encompassed participant demographics, hospital information, education, clinical practice, research involvement, and job satisfaction. We employed multiple logistic regression analyses to identify determinants of satisfaction as a hospitalist. KEY RESULTS: The analysis was based on 79 hospitalists' responses (response rate 26%). Respondents had a median age of 39 years; approximately half were male internal medicine specialists, possessing over 3 years of hospitalist experience. Most respondents were interested in clinical work (94.4%), with only 21.5% interested in research and evidence-based medicine. Over two-thirds indicated that non-clinical duties occupied less than 20% of their time. Overall, job satisfaction among hospitalists averaged 51.9%. Notably, the availability of a research mentor was significantly associated with job satisfaction (P = .011). While hospitalists with more than 3 years of experience, more hospitalists per facility, and autonomy were associated with increased job satisfaction, these associations were not statistically significant. Furthermore, there was no association between night shift work, work type, or work hours and job satisfaction. CONCLUSIONS: Although Korean hospitalists primarily focus on clinical practice, our study underscores the positive impact of mentorship from research mentors on job satisfaction, supported by comprehensive univariate and multivariate analyses. These findings signal a progressive transformation in the role of Korean hospitalists, as they increasingly engage in research alongside patient care.

qMTNet: Accelerated quantitative magnetization transfer imaging with artificial neural networks.

PURPOSE: To develop a set of artificial neural networks, collectively termed qMTNet, to accelerate data acquisition and fitting for quantitative magnetization transfer (qMT) imaging. METHODS: Conventional and interslice qMT data were acquired with two flip angles at six offset frequencies from seven subjects for developing the networks and from four young and four older subjects for testing the generalizability. Two subnetworks, qMTNet-acq and qMTNet-fit, were developed and trained to accelerate data acquisition and fitting, respectively. qMTNet-2 is the sequential application of qMTNet-acq and qMTNet-fit to produce qMT parameters (exchange rate, pool fraction) from undersampled qMT data (two offset frequencies rather than six). qMTNet-1 is one single integrated network having the same functionality as qMTNet-2. qMTNet-fit was compared with a Gaussian kernel-based fitting. qMT parameters generated by the networks were compared with those from ground truth fitted with a dictionary-driven approach. RESULTS: The proposed networks achieved high peak signal-to-noise ratio (>30) and structural similarity index (>97) in reference to the ground truth. qMTNet-fit produced qMT parameters in concordance with the ground truth with better performance than the Gaussian kernel-based fitting. qMTNet-2 and qMTNet-1 could accelerate data acquisition at threefold and accelerate fitting at 5800- and 4218-fold, respectively. qMTNet-1 showed slightly better performance than qMTNet-2, whereas qMTNet-2 was more flexible for applications. CONCLUSION: The proposed single (qMTNet-1) and two joint neural networks (qMTNet-2) can accelerate qMT workflow for both data acquisition and fitting significantly. qMTNet has the potential to accelerate qMT imaging for clinical applications, which warrants further investigation.

Structural insights into the combinatorial effects of antimicrobial peptides reveal a role of aromatic-aromatic interactions in antibacterial synergism.

The recent development of plants that overexpress antimicrobial peptides (AMPs) provides opportunities for controlling plant diseases. Because plants employ a broad-spectrum antimicrobial defense, including those based on AMPs, transgenic modification for AMP overexpression represents a potential way to utilize a defense system already present in plants. Herein, using an array of techniques and approaches, we report on VG16KRKP and KYE28, two antimicrobial peptides, which in combination exhibit synergistic antimicrobial effects against plant pathogens and are resistant against plant proteases. Investigating the structural origin of these synergistic antimicrobial effects with NMR spectroscopy of the complex formed between these two peptides and their mutated analogs, we demonstrate the formation of an unusual peptide complex, characterized by the formation of a bulky hydrophobic hub, stabilized by aromatic zippers. Using three-dimensional structure analyses of the complex in bacterial outer and inner membrane components and when bound to lipopolysaccharide (LPS) or bacterial membrane mimics, we found that this structure is key for elevating antimicrobial potency of the peptide combination. We conclude that the synergistic antimicrobial effects of VG16KRKP and KYE28 arise from the formation of a well-defined amphiphilic dimer in the presence of LPS and also in the cytoplasmic bacterial membrane environment. Together, these findings highlight a new application of solution NMR spectroscopy to solve complex structures to study peptide-peptide interactions, and they underscore the importance of structural insights for elucidating the antimicrobial effects of AMP mixtures.

Magnetic Alignment of Polymer Nanodiscs Probed by Solid-State NMR Spectroscopy.

The ability of amphipathic polymers to self-assemble with lipids and form nanodiscs has been a boon for the field of functional reconstitution of membrane proteins. In a field dominated by detergent micelles, a unique feature of polymer nanodiscs is their much-desired ability to align in the presence of an external magnetic field. Magnetic alignment facilitates the application of solid-state nuclear magnetic resonance (NMR) spectroscopy and aids in the measurement of residual dipolar couplings via well-established solution NMR spectroscopy. In this study, we comprehensively investigate the magnetic alignment properties of styrene maleimide quaternary ammonium (SMA-QA) polymer-based nanodiscs by using 31P and 14N solid-state NMR experiments under static conditions. The results reported herein demonstrate the spontaneous magnetic alignment of large-sized (≥20 nm diameter) SMA-QA nanodiscs (also called as macro-nanodiscs) with the lipid bilayer normal perpendicular to the magnetic field direction. Consequently, the orientation of macro-nanodiscs is further shown to flip the alignment axis parallel to the magnetic field direction upon the addition of a paramagnetic lanthanide salt. These results demonstrate the use of SMA-QA polymer nanodiscs for solid-state NMR applications including structural studies on membrane proteins.

Rapid framework for quantitative magnetization transfer imaging with interslice magnetization transfer and dictionary-driven fitting approaches.

PURPOSE: To develop a rapid framework for quantitative magnetization transfer (qMT) imaging based on the 2D interslice MT and dictionary-driven fitting approaches. METHODS: Sequential balanced steady-state free precession (bSSFP) scanning was performed on a whole human brain in a total of 12 conditions from six different interslice gaps and two different flip angles. To obtain qMT maps, the acquired 12 datasets were fitted to a dictionary predefined by using Bloch equation simulations based on the two-pool MT model. The proposed qMT method was compared to the conventional qMT methods, in terms of qMT parameter maps and processing time. RESULTS: The proposed method yielded qMT maps similar to those of the conventional method, indicating feasibility of modulating MT saturation frequency and power with the interslice gap and flip angle. The whole-brain qMT imaging could be completed in 8 min because of the absence of separate MT pulses. The time for processing qMT parameters was significantly reduced through the dictionary-driven approach; it is 1000 times shorter than that without the dictionary-driven approach and 3 times shorter than that with the spoiled gradient recalled echo-qMT method that uses an analytical solution. CONCLUSION: The proposed dictionary-driven interslice qMT imaging provides qMT maps close to those from the conventional method with significantly reduced scan time and postprocessing time, which can make qMT imaging more clinically acceptable.

Synthesis of Sulfonation Poly(N-propylsulfonicacid isatin biphenylene) for Polymer Electrolyte Membrane Fuel Cell Containing SiO2 Nanocomposite Membrane.

Polymer containing isatin was synthesized by super acid-catalyzed carbon-carbon coupling reaction. Propylsulfonic acid was grafted on isatin unit by substitution reaction with potassium salt of 3-bromo-1-propanesulfonic acid. The sulfonic acid composition was regulated at 25~80 mol% of propylsulfonic acid in order to achieve expected ion exchange capacity of maximum 2.0 meq/g. The copolymers were of high molecular weight (inherent viscosity, ηinh = 1.2 dL/g) to afford a tough membrane by solution casting. Composite membranes were prepared by sulfonated polymer and SiO2 nanoparticles (20 nm, 4~10% wt). All these composite membranes were casted from the solution of sulfonated polymer in dimethylsulfoxide (DMSO) to afford 25 µm. The structural properties of the synthesized polymers were investigated by 1H NMR spectroscopy. The membranes were studied by ion exchange capacity (IEC), water uptake, dimensional stability and proton conductivity assessment by comparing with Nafion®. As increasing the IEC values, the small hydrophobic components induced high proton conductivities and proton diffusion coefficients. These kinds of membranes without ether linkages showed low water swelling as well.

Phase imaging with multiple phase-cycled balanced steady-state free precession at 9.4 T.

While phase imaging with a gradient echo (GRE) sequence is popular, phase imaging with balanced steady-state free precession (bSSFP) has been underexplored. The purpose of this study was to investigate anatomical and functional phase imaging with multiple phase-cycled bSSFP, in expectation of increasing spatial coverage of steep phase-change regions of bSSFP. Eight different dynamic 2D pass-band bSSFP studies at four phase-cycling (PC) angles and two TE /TR values were performed on rat brains at 9.4 T with electrical forepaw stimulation, in comparison with dynamic 2D GRE. Anatomical and functional phase images were obtained by averaging the dynamic phase images and mapping correlation between the dynamic images and the stimulation paradigm, and were compared with their corresponding magnitude images. Phase imaging with 3D pass-band and 3D transition-band bSSFP was also performed for comparison with 3D GRE phase imaging. Two strategies of combining the multiple phase-cycled bSSFP phase images were also proposed. Contrast between white matter and gray matter in bSSFP phase images significantly varied with PC angle and became twice as high as that of GRE phase images at a specific PC angle. With the same total scan time, the combined bSSFP phase images provided stronger phase contrast and visualized neuronal fiber-like structures more clearly than the GRE phase images. The combined phase images of both 3D pass-band and 3D transition-band bSSFP showed phase contrasts stronger than those of the GRE phase images in overall brain regions, even at a longer TE of 20 ms. In contrast, phase functional MRI (fMRI) signals were weak overall and mostly located in draining veins for both bSSFP and GRE. Multiple phase-cycled bSSFP phase imaging is a promising anatomical imaging technique, while its usage as fMRI does not seem desirable with the current approach.

Gender-Based Correlation Profiles Among the Release Factors and Distance Thrown in Paralympic Seated Shot Put.

The purpose of this study was to investigate the relationships among release factors (speed, height, and angle) and distance thrown in Paralympic seated shot put. Forty-eight trials performed by 11 men and 5 women during the 2012 US Paralympic trials in track and field were analyzed. With both genders combined, release speed (r = .95, p < .01) and angle (r = .51, p < .01) showed significant correlations to distance thrown. Release speed (r = .94, p < .01) in men and all release factors (r = .60-.98, p < .02) in women showed significant correlations to distance. Release speed and angle were identified as important predictors of the distance, explaining over 89-96% of the variance in distance thrown. Unlike athletes without disability, seated shot-putters exhibited significant positive speed-angle correlations (combined: r = .37, p < .01; women: r = .57, p = .03). Application of these results should address a focus in training on generating speed through the release point with a consistent release angle.

The effect of complex posttraumatic stress and poverty on quality of life among adult survivors of childhood institutional maltreatment: evidence from survivors of the 'Hyeongje Welfare Institution' in South Korea.

Background: Childhood institutional maltreatment (IM) is associated with both complex posttraumatic stress disorder (CTPSD) and poverty in adulthood life, each of which may impact an individual's quality of life (QoL). To find implications for clinical practice and policy making for adult survivors with childhood IM experiences, it is necessary to conduct research examining their current QoL and identifying related factors.Objective: By applying the model of the conservation of resources theory, we focused on how adulthood QoL can be indicated by childhood IM as well as the life outcomes of IM such as additional lifetime trauma, CPTSD, and poverty.Methods: In a cross-sectional study, self-report data were collected from 127 adults who were survivors of the 'Hyeongje' childhood IM in South Korea. We conducted regression analyses of childhood IM experiences, trauma experiences after escape from the institution, current CPTSD symptoms, and current poverty experiences on current QoL.Results: The duration of placement at the 'Hyeongje' (ß = .24, p = .009) was associated with trauma experiences after escape from the institution. Trauma experiences after escape from the institution (ß = .25, p = .007) were associated with CPTSD symptoms. CPTSD symptoms (ß = .26, p = .005) were associated with poverty, and both CPTSD symptoms (ß = -.52, p < .001) and poverty (ß = -.26, p = .003) were negatively associated with current QoL.Conclusions: Prolonged childhood IM brings about loss spirals by increasing an individual's exposure to experiences of further cumulative trauma, CPTSD, and poverty. There is a need for due diligence-based policy making and public support from the government to help create upward spirals for QoL. This may include the imminent detection and rescue of children as well as providing a safe environment, offering multidisciplinary interventions including evidence-based treatment for CPTSD, and considering economic support including collective reparations.

Duration of placement at the 'Hyeongje' institution was associated with additional trauma experience after escaping the institution.Cumulative trauma after escape was associated with CPTSD symptoms; CPTSD symptoms were associated with poverty; and both CPTSD symptoms and poverty were associated with poor current QoL.Multidisciplinary interventions including evidence-based treatment for CPTSD and considering economic resources for childhood IM survivors would be crucial in increasing QoL.

Weld Zone Analysis Based on FCAW Mechanical Characteristics and Heat Transfer Analysis of 316L Stainless Steel for Liquefied Hydrogen Tanks.

The International Maritime Organization (IMO) is currently rolling out more restrictive regulations in order to achieve net-zero GHG emissions by 2050. In response, the shipping industry is planning to pivot to green energy sources such as hydrogen fuel. However, since hydrogen has an extremely low boiling point (-253 °C), materials for storing liquid hydrogen must be highly resistant to low-temperature brittleness and hydrogen embrittlement. A 316L stainless steel is a typical material that meets these requirements, and various welds have been studied. In this study, 3 pass butt welding was performed by applying the FCAW (flux cored arc welding) process to 10 mm thick ASTM-A240M-316L stainless steel, with the size of the fusion zone and HAZ investigated by mechanical testing and heat transfer FE analysis according to process variables, such as heat input, welding speed, and the number of passes. In all cases, the yield and tensile strengths were about 10% and 3% higher than the base metal, respectively. Furthermore, heat transfer FE analysis showed an average error rate of 1.3% for penetration and 10.5% for width and confirmed the size of the HAZ, which experienced temperatures between 500 °C and 800 °C.

Prediction of Antibiotic Resistance in Patients With a Urinary Tract Infection: Algorithm Development and Validation.

BACKGROUND: The early prediction of antibiotic resistance in patients with a urinary tract infection (UTI) is important to guide appropriate antibiotic therapy selection. OBJECTIVE: In this study, we aimed to predict antibiotic resistance in patients with a UTI. Additionally, we aimed to interpret the machine learning models we developed. METHODS: The electronic medical records of patients who were admitted to Yongin Severance Hospital, South Korea were used. A total of 71 features extracted from patients' admission, diagnosis, prescription, and microbiology records were used for classification. UTI pathogens were classified as either sensitive or resistant to cephalosporin, piperacillin-tazobactam (TZP), carbapenem, trimethoprim-sulfamethoxazole (TMP-SMX), and fluoroquinolone. To analyze how each variable contributed to the machine learning model's predictions of antibiotic resistance, we used the Shapley Additive Explanations method. Finally, a prototype machine learning-based clinical decision support system was proposed to provide clinicians the resistance probabilities for each antibiotic. RESULTS: The data set included 3535, 737, 708, 1582, and 1365 samples for cephalosporin, TZP, TMP-SMX, fluoroquinolone, and carbapenem resistance prediction models, respectively. The area under the receiver operating characteristic curve values of the random forest models were 0.777 (95% CI 0.775-0.779), 0.864 (95% CI 0.862-0.867), 0.877 (95% CI 0.874-0.880), 0.881 (95% CI 0.879-0.882), and 0.884 (95% CI 0.884-0.885) in the training set and 0.638 (95% CI 0.635-0.642), 0.630 (95% CI 0.626-0.634), 0.665 (95% CI 0.659-0.671), 0.670 (95% CI 0.666-0.673), and 0.721 (95% CI 0.718-0.724) in the test set for predicting resistance to cephalosporin, TZP, carbapenem, TMP-SMX, and fluoroquinolone, respectively. The number of previous visits, first culture after admission, chronic lower respiratory diseases, administration of drugs before infection, and exposure time to these drugs were found to be important variables for predicting antibiotic resistance. CONCLUSIONS: The study results demonstrated the potential of machine learning to predict antibiotic resistance in patients with a UTI. Machine learning can assist clinicians in making decisions regarding the selection of appropriate antibiotic therapy in patients with a UTI.

Gender differences in psychosocial determinants of hand hygiene among physicians.

OBJECTIVE: We investigated gender differences in psychosocial determinants that affect hand hygiene (HH) performance among physicians. DESIGN: The survey included a structured questionnaire with 7 parts: self-assessment of HH execution rate; knowledge, attitude, and behavior regarding HH; internal and emotional motivation for better HH; barriers to HH; need for external reminders; preference for alcohol gel; and embarrassment due to supervision. SETTING: The study was conducted across 4 academic referral hospitals in Korea. PARTICIPANTS: Physicians who worked at these hospitals were surveyed. METHODS: The survey questionnaire was sent to 994 physicians of the hospitals in July 2018 via email or paper. Differences in psychosocial determinants of HH among physicians were analyzed by gender using an independent t test or the Fisher exact test. RESULTS: Of the 994 physicians, 201 (20.2%) responded to the survey. Among them, 129 (63.5%) were men. Male physicians identified 4 barriers as significant: time wasted on HH (P = .034); HH is not a habit (P = .004); often forgetting about HH situations (P = .002); and no disadvantage when I do not perform HH (P = .005). Female physicians identified pain and dryness of the hands as a significant obstacle (P = .010), and they had a higher tendency to feel uncomfortable when a fellow employee performed inadequate HH (P = .098). Among the respondents, 26.6% identified diversifying the types of hand sanitizers as their first choice for overcoming barriers to improving HH, followed by providing reminders (15.6%) and soap and paper towels in each hospital room (13.0%). CONCLUSION: A significant difference in the barriers to HH existed between male and female physicians. Promoting HH activities could help increase HH compliance.

Influences of genetic variation of endothelin-1 gene on effects of 16-week combined exercise on clinical and physical parameters in middle-aged women.

BACKGROUND AND OBJECTIVE. In this study, we attempted to determine whether the C/T polymorphism of the ET-1 gene was significantly associated with changes in several clinical characteristics after the 16-week combined exercise program in overweight middle-aged women. MATERIAL AND METHODS. The C/T polymorphism of the ET-1 gene was assayed using polymerase chain reaction, i.e., the TaqI restriction fragment length polymorphism method. RESULTS. The genetic variation in the ET-1 gene showed a significant association with the serum LDL cholesterol level as well as several parameters of physical fitness, including muscular endurance and power of the participants (P<0.05). In addition, this genetic variation showed a significant association with changes in muscular strength of the participants after the 16-week combined exercise program (P<0.05). CONCLUSIONS. Our data suggest that the C/T substitution on intron 4 of the ET-1 gene may be a useful genetic marker influencing muscular strength through a gene-exercise interaction and is associated with an interindividual difference of cardiovascular risk factors and parameters of physical fitness.

An Improved Method for Deriving the Heat Source Model for FCAW of 9% Nickel Steel for Cryogenic Tanks.

The International Maritime Organization (IMO) is tightening regulations on air pollutants. Consequently, more LNG-powered ships are being used to adhere to the sulfur oxide regulations. Among the tank materials for storing LNG, 9% nickel steel is widely used for cryogenic tanks and containers due to its high cryogenic impact toughness and high yield strength. Hence, numerous studies have sought to predict 9% nickel steel welding distortion. Previously, a methodology to derive the optimal parameters constituting the Goldak welding heat source for arc welding was developed. This was achieved by integrating heat transfer finite element analysis and optimization algorithms. However, this process is time-consuming, and the resulting shape of the weld differs by ~15% from its actual size. Therefore, this study proposes a simplified model to reduce the analysis time required for the arc welding process. Moreover, a new objective function and temperature constraints are presented to derive a more sophisticated heat source model for arc welding. As a result, the analysis time was reduced by ~70% compared to that previously reported, and the error rates of the weld geometry and HAZ size were within 10% and 15% of the actual weld, respectively. The findings of this study provide a strategy to rapidly predict welding distortion in the field, which can inform the revision of welding guidelines and overall welded structure designs.

Novel Risks of Unfavorable Corticosteroid Response in Patients with Mild-to-Moderate COVID-19 Identified Using Artificial Intelligence-Assisted Analysis of Chest Radiographs.

The prediction of corticosteroid responses in coronavirus disease 2019 (COVID-19) patients is crucial in clinical practice, and exploring the role of artificial intelligence (AI)-assisted analysis of chest radiographs (CXR) is warranted. This retrospective case-control study involving mild-to-moderate COVID-19 patients treated with corticosteroids was conducted from 4 September 2021, to 30 August 2022. The primary endpoint of the study was corticosteroid responsiveness, defined as the advancement of two or more of the eight-categories-ordinal scale. Serial abnormality scores for consolidation and pleural effusion on CXR were obtained using a commercial AI-based software based on days from the onset of symptoms. Amongst the 258 participants included in the analysis, 147 (57%) were male. Multivariable logistic regression analysis revealed that high pleural effusion score at 6-9 days from onset of symptoms (adjusted odds ratio of (aOR): 1.022, 95% confidence interval (CI): 1.003-1.042, p = 0.020) and consolidation scores up to 9 days from onset of symptoms (0-2 days: aOR: 1.025, 95% CI: 1.006-1.045, p = 0.010; 3-5 days: aOR: 1.03 95% CI: 1.011-1.051, p = 0.002; 6-9 days: aOR; 1.052, 95% CI: 1.015-1.089, p = 0.005) were associated with an unfavorable corticosteroid response. AI-generated scores could help intervene in the use of corticosteroids in COVID-19 patients who would not benefit from them.

A Graphene-Based Polymer-Dispersed Liquid Crystal Device Enabled through a Water-Induced Interface Cleaning Process.

We report the use of four-layer graphene (4LG) as a highly reliable transparent conductive electrode (TCE) for polymer-dispersed liquid crystal (PDLC)-based smart window devices. The adhesion between 4LG and the substrate was successfully improved through a water-induced interface-cleaning (WIIC) process. We compared the performance of a device with a WIIC-processed 4LG electrode with that of devices with a conventional indium tin oxide (ITO) electrode and a 4LG electrode without a WIIC. With the application of the WIIC process, the PDLC smart window with a 4LG electrode exhibited reduced turn-on voltage and haze compared to 4LG without the WIIC process and characteristics comparable to those of the ITO electrode. The WIIC-processed 4LG electrode demonstrated enhanced electrical properties and better optical performance, leading to improved device efficiency and reliability. Furthermore, our study revealed that the WIIC process not only improved the adhesion between 4LG and the substrate but also enhanced the compatibility and interfacial interactions, resulting in the superior performance of the smart window device. These findings suggest that 4LG with WIIC holds great promise as a transparent conductive electrode for flexible smart windows, offering a cost-effective and efficient alternative to conventional ITO electrodes.

Hand hygiene knowledge, attitude, barriers and improvement measures among healthcare workers in the Republic of Korea: a cross-sectional survey exploring interprofessional differences.

BACKGROUND: Hand hygiene (HH) is a fundamental component of infection prevention and control in healthcare settings. This study aimed to identify knowledge, attitude, and barriers to HH according to occupational groups and strategies to increase the rate of HH compliance among healthcare workers (HCWs). METHODS: This cross-sectional survey was conducted in July 2018 at four university-affiliated hospitals. The survey comprised seven parts with 49 items, including self-reported HH compliance, knowledge, attitudes, behaviours, barriers to HH, and improvement strategies. RESULTS: A total of 1046 HCWs participated in the survey. The nursing group's self-reported HH compliance rate was the highest, followed by other HCWs and physicians. The scores regarding knowledge, attitudes, and behaviours regarding HH were the highest in the nursing group. The nursing group also had higher internal and emotional motivation scores. Physicians and nurses found HH the most challenging in emergencies, while other HCWs considered skin problems caused by HH products the most significant barrier. Among 12 improvement measures, approximately 20% of the respondents ranked "diversify types of hand sanitisers," "install soap and paper towels in each hospital room," and "change perception through various HH campaigns" as the top three priorities. The physician group deemed the timely reminder of HH compliance as the second most critical improvement measure. CONCLUSION: Differences in knowledge, attitude and barriers hindering HH compliance and improvement plans were identified for each group. The findings suggest that targeted interventions tailored to the specific needs of different occupational groups may effectively improve HH compliance in healthcare settings.

A Study to Derive Equivalent Mechanical Properties of Porous Materials with Orthotropic Elasticity.

The need for diverse materials has emerged as industry becomes more developed, and there is a need for materials with pores in various industries, including the energy storage field. However, there is difficulty in product design and development using the finite element method because the mechanical properties of a porous material are different from those of a base material due to the pores. Therefore, in this study, a Python program that can estimate the equivalent property of a material with pores was developed and its matching was verified through comparison with the measurement results. For high-efficiency calculation, the pores were assumed to be circular or elliptical, and they were also assumed to be equally distributed in each direction. The material with pores was assumed to be an orthotropic material, and its equivalent mechanical properties were calculated using the equivalent strain and equivalent stress by using the appropriate material property matrix. The material properties of a specimen with the simulated pores were measured using UTM, and the results were compared with the simulation results to confirm that the degree of matching achieved 6.4%. It is expected that this study will contribute to the design and development of a product in the industrial field.

Research for the Optimal Flux-Cored Arc Welding Process of 9% Nickel Steel Using Multi Object Optimization with Solidification Crack Susceptibility.

The environment of the global shipbuilding market is changing rapidly. Recently, the International Maritime Organization (IMO) has tightened regulations on sulfur oxide content standards for marine fuels and tightened sulfur oxide emission standards for the entire coastal region of China to consider the environment globally and use LNG as a fuel. There is a tendency for the number of vessels to operate to increase significantly. To use cryogenic LNG fuel, various pieces of equipment, such as storage tanks or valves, are required, and equipment using steel, which has excellent impact toughness in cryogenic environments, is required. Four steel types are specified in the IGG Code, and 9% Ni steel is mostly used for LNG fuel equipment. However, to secure safety at cryogenic temperatures, a systematic study investigating the causes of quality deterioration occurring in the 9% Ni steel welding process is required and a discrimination function capable of quality evaluation is urgent. Therefore, this study proposes a plan where the uniform quality of 9% Nickel steel is secured by reviewing the tendency of the solidification crack susceptibility among the quality problems of cryogenic steel to establish the criteria for quality deterioration and to develop a system capable of quality discrimination and defect avoidance.