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The effects of wet chemical treatments before treatment using (NH4)2S solutions in atomic layer deposition Al2O3/InGaAs metal-oxide-semiconductor (MOS) interfaces are experimentally examined. It is found that no chemical treatment before sulfur passivation leads to high interface state density (Dit) in spite of the (NH4)2S treatment. Furthermore, the value of Dit is dependent among the pretreatments using NH4OH, HCl, and BHF solutions before the sulfur treatment. HCl + (NH4)2S and BHF + (NH4)2S combinations show the lowest values of Dit. In addition, all of the Al2O3/InGaAs MOS interfaces with the sulfur treatment show a small amount of arsenic oxide. Thus, much higher Dit of the interfaces with the sulfur treatment indicates that the amount of arsenic oxide is not a deterministic factor for Dit. On the other hand, the amount of arsenic oxide before the sulfur treatment is found to correlate with Dit after sulfur treatment. Also, the interfaces with higher Dit after the sulfur treatment show a larger number of sulfur atoms remaining at the interfaces. These experimental results mean that there is a strong correlation among Dit, the amount of arsenic oxide, and the number of sulfur atoms remaining at the Al2O3/InGaAs interfaces. As a result, we can interpret for the present experimental results that the sulfur treatment can have two opposite impacts on Dit at the Al2O3/InGaAs interfaces: the decrease in Dit due to etching of native oxides and suppression of oxidation by sulfur passivation and the increase in Dit due to defect generation through some interaction between sulfur and arsenic oxide. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We aimed to assess the impact of the coronavirus disease 2019 (COVID-19) pandemic on the incidence of intussusception. MATERIALS AND METHODS: Literature search of the PubMed and EMBASE databases was conducted for articles published in English until August 5, 2022. RESULTS: Overall, 127 articles were retrieved, and five studies from South Korea (n=4) and the United States of America (n=1) containing clinical data from single-center medical records to nationwide databases were ultimately included in the systematic review. All the included studies reported that the incidence of intussusception decreased significantly during the pandemic period compared with the pre-pandemic period. The communicable disease incidence tended to decrease even as the incidence of non-communicable diseases did not significantly change. There was no significant difference in the time to diagnosis between the pre-pandemic and pandemic periods; however, the time to radiologic reduction was significantly longer or not depending on the study. CONCLUSIONS: The COVID-19 pandemic significantly reduced the incidence of intussusception in children, supporting the hypothesis that infection plays a major role in the etiology of intussusception. Future studies in the late pandemic or post-pandemic era, which would represent the level of implementation of non-pharmaceutical interventions and social distancing as well as additional data from various countries will be needed. [ABSTRACT FROM AUTHOR]

The relationship between substrate hole currents and interface state generation in Al2O3/InGaAs n-channel metal-oxide-semiconductor field-effect transistors (MOSFETs) is experimentally studied for the MOSFETs with three different Al2O3 thicknesses of 3.2, 5.2, and 8.2 nm. The constant positive gate bias stress is applied. Then, the substrate hole current, monitored in the carrier separation setup, is clearly observed for the InGaAs n-channel MOSFETs. It is found that the density of the generated interface states (ΔDit) is uniquely represented as a function of the total hole fluence (Nhole), given by integrating the substrate hole current over time, not the total electron fluence. This experimental result strongly supports that interface state generation is triggered by holes induced by electrical stress, regardless of the thickness of Al2O3. It is also found that ΔDit in 3.2- and 5.2-nm-thick Al2O3 MOSFETs, expressed by the universal single line against Nhole, is lower than that in 8.2-nm-thick Al2O3 MOSFETs, which can be explained by the difference of the origin of the hole generation in the Al2O3/InGaAs metal-oxide-semiconductor interface. Judging from the similarity of these features with ΔDit in SiO2/Si n-MOSFETs reported previously, the Al2O3/InGaAs interfaces have the same physical origin of interface state generation as SiO2/Si interfaces. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Achromobacter spp. are aerobic, non-fermentative Gram-negative bacilli that can be widely found in aquatic environments. Nosocomial outbreaks and pseudo-outbreaks of Achromobacter spp. bacteremia have been recognized for decades. Notably, commonly used germicides in hospital settings constitute important sources for these outbreaks. This review aims at summarizing the latest studies and presents the characteristics of nosocomial outbreaks of Achromobacter spp. bacteremia caused by germicide contamination. MATERIALS AND METHODS: A systematic search of the PubMed and EMBASE databases was conducted for articles published in English between January 1, 2000, and June 10, 2022. RESULTS: Overall, 170 articles were retrieved, and 7 studies were finally included in the systematic review. Whether true or pseudo-bacteremia, positive blood culture results were most commonly reported in immunosuppressed patients or those with indwelling catheters. The most commonly reported contaminated germicide was chlorhexidine solution used as both an antiseptic and disinfectant. Atomizers, dispensers, and various product containers were identified as reservoirs. The prognoses of the affected patients were generally favorable. CONCLUSIONS: Awareness about the high survival ability of Achromobacter spp. in germicides and the possible hospital reservoirs of these microbes will help to improve infection control and prevent nosocomial outbreaks or pseudo-outbreaks caused by Achromobacter spp. [ABSTRACT FROM AUTHOR]