A Novel Source/Drain Extension Scheme with Laser-Spike Annealing for Nanosheet Field-Effect Transistors in 3D ICs.

This study proposed a novel source/drain (S/D) extension scheme to increase the stress in nanosheet (NS) field-effect transistors (NSFETs) and investigated the scheme by using technology-computer-aided-design simulations. In three-dimensional integrated circuits, transistors in the bottom tier were exposed to subsequent processes; therefore, selective annealing, such as laser-spike annealing (LSA), should be applied. However, the application of the LSA process to NSFETs significantly decreased the on-state current (Ion) owing to diffusionless S/D dopants. Furthermore, the barrier height below the inner spacer was not lowered even under on-state bias conditions because ultra-shallow junctions between the NS and S/D were formed far from the gate metal. However, the proposed S/D extension scheme overcame these Ion reduction issues by adding an NS-channel-etching process before S/D formation. A larger S/D volume induced a larger stress in the NS channels; thus, the stress was boosted by over 25%. Additionally, an increase in carrier concentrations in the NS channels improved Ion. Therefore, Ion increased by approximately 21.7% (37.4%) in NFETs (PFETs) compared with NSFETs without the proposed scheme. Additionally, the RC delay was improved by 2.03% (9.27%) in NFETs (PFETs) compared with NSFETs using rapid thermal annealing. Therefore, the S/D extension scheme overcame the Ion reduction issues encountered in LSA and significantly enhanced the AC/DC performance.

Analysis of Changes in Antibiotic Use Patterns in Korean Hospitals during the COVID-19 Pandemic.

With the onset of the coronavirus disease 2019 (COVID-19) pandemic, changes in patient care and antibiotic use have occurred in hospitals. The data of the National Health Insurance System's claims of inpatients from all hospitals in Korea between January 2019 and December 2020 were obtained from the Health Insurance Review & Assessment Service and analyzed. The trend in the use of all antibacterial agents in both hospitals declined for the total number of COVID-19 patients at the bottom 10% and those in the top 10%. Specifically, a decreasing trend in the use of broad-spectrum antibacterial agents predominantly prescribed for community-acquired cases and narrow-spectrum beta-lactam agents were observed in both hospitals. In the aftermath of the COVID-19 pandemic, the total use of antibacterial agents has gradually decreased among patients with pneumonia and those with severe COVID-19. In contrast, its use has increased gradually among those with mild to moderate COVID-19. A decreasing trend in overall antibiotic use was observed during the COVID-19 pandemic, and an increasing trend in antibiotic use was observed in patients with mild to moderate COVID-19 in Korean hospitals.

Effect of discontinuation of an antimicrobial stewardship programme on the antibiotic usage pattern.

OBJECTIVES: This study aimed to analyse the effect of discontinuation of antimicrobial stewardship programme (ASP) activity on the usage pattern of antibiotics. METHODS: An interrupted time-series analysis assessing the trends in antibiotic use was conducted between September 2015 and August 2019 in an 859-bed university-affiliated hospital in Korea, where all ASP activities were discontinued in March 2018. The major activity of the ASP was a restrictive antibiotic programme. RESULTS: The use of restrictive antibiotics increased immediately after the discontinuation of the ASP by 41.06 days of therapy (DOT)/1000 patient-days in the general ward (95% confidence interval (CI) 21.04-61.08) and by 391.04 DOT/1000 patient-days in the intensive care unit (ICU) (95%CI 207.56-574.51). In addition, there were positive changes in the slope for the use of restrictive antibiotics in the general ward (7.06 DOT/1000 patient-days per month, 95%CI 4.63-9.50) and ICU (35.95 DOT/1000 patient-days per month, 95%CI 18.70-53.19). The use of broad-spectrum antibiotics in the general ward significantly decreased (-87.54 DOT/1000 patient-days, 95%CI -149.29 to -25.79). For non-broad-spectrum antibiotics, there were positive changes in the slope in the general ward (16.54 DOT/1000 patient-days per month, 95%CI 12.99-20.09) and ICU (12.85 DOT/1000 patient-days per month, 95%CI 2.32-23.38). CONCLUSIONS: After discontinuation of the ASP, antibiotic usage patterns rapidly returned to the patterns prior to the implementation of the programme.

Ten-year trends in antibiotic usage at a tertiary care hospital in Korea, 2004 to 2013.

BACKGROUND/AIMS: This study was performed to evaluate trends in antibiotic usage at a tertiary care hospital in Korea. METHODS: This study collated antibiotic prescription data and total patient days for inpatients at a tertiary care hospital in Korea between 2004 and 2013. The consumption of each class of antibiotic was converted to defined daily dose (DDD)/1,000 patient-days. We defined 3rd generation cephalosporins, 4th generation cephalosporins, ß-lactam/ß-lactamase inhibitors, and fluoroquinolones as broad-spectrum antibiotics; carbapenems, tigecycline, glycopeptides, oxazolidinone, and polymyxin were defined as antibiotics against multidrug-resistant (MDR) pathogens. Other antibiotic classes were defined as nonbroad-spectrum antibiotics. RESULTS: Mean antibiotic consumption was 920.69 DDD/1,000 patient-days. The proportions of broad-spectrum antibiotics, antibiotics against MDR pathogens, and nonbroad-spectrum antibiotics were 41.8% (384.48/920.69), 3.5% (32.24/920.69), and 54.7% (503.97/920.69), respectively. Consumption of broad-spectrum antibiotics (coefficient for time 0.141; p = 0.049) and antibiotics against MDR pathogens (coefficient for time 0.185; p < 0.001) showed a significant increasing trend over the study period. Nonbroad-spectrum antibiotic consumption showed a significant decreasing trend over the study period (coefficient for time -2.601; p < 0.001). CONCLUSION: Over the 10-year period, a stepwise increase in the consumption of broad-spectrum antibiotics and antibiotics against MDR pathogens was observed at a tertiary care hospital in Korea. Conversely, during the same period, nonbroad-spectrum antibiotic consumption showed a significant decreasing trend.

Trends and correlation between antibiotic usage and resistance pattern among hospitalized patients at university hospitals in Korea, 2004 to 2012: A nationwide multicenter study.

The aim of this study was to evaluate the changing pattern of antibiotic usage and antimicrobial resistance of bacterial pathogens among hospitalized patients in Korea. We simultaneously investigated the correlation between antimicrobial resistance and antibiotic consumption.Data on total antibiotic prescriptions, patient days, and antimicrobial sensitivity tests among inpatients from 6 university hospitals in Korea in 2004, 2008, and 2012 were collected. The consumption of each antibiotic class was converted to defined daily dose/1000 patient-days by using the anatomical therapeutic chemical classification system by the World Health Organization. We defined third-generation cephalosporins (3rd CEPs), fourth-generation cephalosporins, beta-lactam/beta-lactamase inhibitors, and fluoroquinolones (FQs) as broad-spectrum antibiotics and carbapenems, tigecycline, glycopeptides, oxazolidinone, and polymyxin as antibiotics against multidrug-resistant (MDR) pathogens.A 15.1% decrease in total antibiotic consumption was observed in 2012 compared to that observed in 2004. In contrast, a 10.2% and 70.7% increase in broad-spectrum antibiotics and antibiotics against MDR pathogens were observed, respectively, in the same period. The resistance rate of Escherichia coli to 3rd CEPs (17.6% in 2004, 21.7% in 2008, and 33.8% in 2012, P <.001) and ciprofloxacin (37.5% in 2004, 38.7% in 2008, and 46.6% in 2012, P = .001) demonstrated a significantly increasing trend. Similarly, the resistance rate of Klebsiella pneumoniae to 3rd CEPs (34.3% in 2004, 33.7% in 2008, and 44.5% in 2012, P <.001) gradually increased. Resistance of Acinetobacter baumanii and Pseudomonas aeruginosa to imipenem significantly increased throughout the study period (A baumanii: 8.9% in 2004, 40.8% in 2008, and 65.3% in 2012, P <.001; P aeruginosa: 25.1% in 2004, 31.5% in 2008, and 29.7% in 2008, P = .050).The consumption of carbapenems and FQs demonstrated significant positive correlation for resistance of E coli or K pneumoniae to 3rd CEPs as well as E coli or K pneumoniae to ciprofloxacin. Increasing resistance of A baumanii to ciprofloxacin was significantly correlated with increasing consumption of FQs; increasing resistance of A baumanii to imipenem was significantly correlated with increasing consumption of carbapenems.In conclusion, overall antimicrobial resistance increased and consumption of broad-spectrum antibiotics and antibiotics against MDR pathogens subsequently increased in Korean hospitals.

Impact of an infectious diseases specialist-led antimicrobial stewardship programmes on antibiotic use and antimicrobial resistance in a large Korean hospital.

The aim of this study was to evaluate the impact of an infectious diseases specialist (IDS)-led antimicrobial stewardship programmes (ASPs) in a large Korean hospital. An interrupted time series analysis assessing the trends in antibiotic use and antimicrobial resistance rate of major pathogens between September 2015 and August 2017 was performed in an 859-bed university-affiliated hospital in Korea. The restrictive measure for designated antibiotics led by an IDS reduced carbapenems usage by -4.57 days of therapy (DOT)/1,000 patient-days per month in general wards (GWs) (95% confidence interval [CI], -6.69 to -2.46; P < 0.001), and by -41.50 DOT/1,000 patient-days per month in intensive care units (ICUs) (95% CI, -57.91 to -25.10; P < 0.001). Similarly, glycopeptides usage decreased by -2.61 DOT/1,000 patient-days per month in GWs (95% CI, -4.43 to -0.79; P = 0.007), and -27.41 DOT/1,000 patient-days per month in ICUs (95% CI, -47.03 to -7.79; P = 0.009). Use of 3rd generation cephalosporins, beta-lactam/beta-lactamase inhibitors, and fluoroquinolones in GWs showed change comparable with that of carbapenems or glycopeptides use. Furthermore, trends of antimicrobial resistance rate of Staphylococcus aureus to gentamicin in GWs, Staphylococcus aureus to ciprofloxacin and oxacillin in ICUs, and Pseudomonas aeruginosa to imipenem in ICUs decreased in slope in the intervention period. The in-hospital mortality rate per 1,000 patient-days among ICU patients remained stable between the pre-intervention and intervention periods. In conclusion, an IDS-led ASPs could enact a meaningful reduction in antibiotic use, and a decrease in antibiotic resistance rate, without changing mortality rates in a large Korean hospital.

A few antibiotics can represent the total hospital antibiotic consumption.

BACKGROUND: Appropriate antibiotic use has become an important issue. However, collecting data on the use of all antibiotics in a hospital is difficult without an advanced computerized system and dedicated staff. This paper examines if 1-3 antibiotics can satisfactorily represent the total antibiotic consumption at the hospital level. METHODS: We collected antibiotic data from six large university hospitals in Korea for some years between 2004 and 2012. Since the total antibiotics consist of a few chosen representative antibiotics and the rest, we used those chosen antibiotics along with additional variables constructed only with t (time) such as t, t 2 , and t 3 to capture the time trend and whether t belongs to each month or not to capture the monthly variations. The ordinary least squares method was used to explain the total antibiotic amount with these variables, and then the estimated model was employed to predict the use for 2013. To determine which antibiotics were the most representative in tracking general trends in antibiotic use over time, we tried various combinations of antibiotics to find the combination that best minimized the 2013 prediction error. RESULTS: We found that fluoroquinolones and aminoglycosides were the most representative, followed by beta-lactam/beta-lactamase inhibitors and 4th-generation and 3rd-generation cephalosporins. The mean prediction error over 12 months in 2013 with these few antibiotics was only 1-3% of the monthly antibiotic consumption amount. CONCLUSIONS: The total antibiotic consumption amount at the hospital level can be represented sufficiently by a few antibiotics, such as fluoroquinolones and aminoglycosides, which means that hospitals can save resources by tracing only the usage of those few antibiotics instead of the entire inventory. Since the choice of fluoroquinolones and aminoglycosides is based solely on our Korean data, other hospitals may follow the same modelling methodology to find their own representative antibiotics.