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BACKGROUND: Organic acids on the surface of human hands contribute to the barrier against transient pathogens. This is the first study to explore the synergistic contribution of lactic acid and other hand environment-related features on the antibacterial properties of the hand surface. MATERIALS AND METHODS: We estimated the contribution of fingerprint depth, skin pH, stratum corneum water content, skin temperature, and sweat rate of the hands to the infection barrier using an observational survey of 105 subjects. The relationship between each factor and the antibacterial activity of the hands was analyzed using Pearson's correlation coefficient. We performed molecular dynamics simulations to study the interaction between lactic acid and bacterial membranes. RESULTS: The amount of lactic acid on the hands and skin temperature contributed positively to the antimicrobial activity (r = 0.437 and P = 3.18 × 10-6 , r = 0.500 and P = 5.66 × 10-8 , respectively), while the skin pH contributed negatively (r = -0.471, P = 3.99 × 10-7 ). The predicted value of the combined antimicrobial effect of these parameters was [antimicrobial activity] = 0.21 × [lactic acid] - 0.25 × [skin pH] + 0.26 × [skin temperature] + 0.98. The coefficient of determination (R2 ) was 0.50. CONCLUSION: The increase in the amount of non-ionic lactic acid due to lower pH and improvement in the fluidity of the cell membrane due to higher temperatures enable the efficient transport of lactic acid into cells and subsequent antimicrobial activity. The proposed mechanism could help to develop an effective hand infection barrier technology.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has contributed to significant morbidity and mortality globally. Despite prior findings detecting SARS-CoV-2 genes on environmental surfaces, little research has examined the role of environmental viruses on disease spread. Thus, the present study examined the SARS-CoV-2 contamination in the hospital setting. In the study, 14 sites in the hospital room and one site on the back of nurses’ scrubs were sampled for virus detection. Of the 134 collected samples, 66 were positive for viral RNA (49.3%). Viral RNA detection rates were highest for samples obtained from patients’ masks and pajamas, and the likelihood of viral positivity decreased with increasing distance from the patient’s mouth. Meanwhile, SARS-CoV-2 was detected at sites distant from the patient’s mouth, including the shower room and patient room doorknobs, indicating the potential for the virus to spread through hand contact by infected patients. In addition, infectious virus was detected in 3 samples (2.2%). To our knowledge, this is the first report of SARS-CoV-2, which retain infectious, detected on environmental surfaces. Our findings illustrated the need for frequent cleaning of surfaces to prevent the in-hospital spread of COVID-19.

The compact model of HIroshima-University Starc Igfet Model (HiSIM)_GaN for GaN-HEMT devices is reported, which solves the Poisson equation iteratively, in a similar way as the industry-standard compact HiSIM models for other semiconductor devices. The model considers all possible charges induced within the device, including the dynamically varying trap density. It is verified that the model can reproduce the 2-D-device simulation results accurately. In particular, the operation frequency dependence of the current collapse can also be captured correctly based on the trap time constant.

Although the surface of hands in humans is known to harbor high levels of antimicrobial activity, reports investigating the relationship between antimicrobial activity and morbidity in infectious diseases are lacking. Additionally, the precise components involved in this activity are not known. Therefore, in this study, a method was developed to quantitatively measure the antimicrobial activity of the components found on the surface of hands, which was then compared with the medical history of the participants for infectious diseases. As a result, the antimicrobial activity of the surface of the hands was found to be positively associated with the history of infection in individuals. Furthermore, a comprehensive analysis of the components on the surface of hands indicated that organic acids and antimicrobial peptides are highly correlated with antimicrobial activity. The high amounts of lactic acid found on the surface of hands suggested it is an important factor in the hand surface infection barrier. Here we showed that the application of lactic acid within the range of the amounts present on the hand surface was found to significantly improve the antimicrobial activity of the hands. Taken together, these results demonstrate that this new method can be used to quantify antimicrobial activity, which opens new avenues for the development of hand hygiene practices by enhancing the antimicrobial activity on the surface of hands using natural ingredients against pathogens.

Solid lubricants have long been widely used to enhance lubricity and to achieve a longer die life in the field of tribological applications. Molybdenum disulfide (MoS 2 ) is the most desirable solid lubricant because of its low friction coefficient, good anti-seizure ability stemming from easy cleavage and excellent adhesion to the metal surface. Although MoS 2 performs well, it has a disadvantage in that its black appearance significantly stains the working environment. Therefore, non-black solid lubricants are strongly desired. Herein, we investigated the properties of a clay-organic intercalation compound as a solid lubricant. It is well known that some types of layered clay minerals have a cation exchange capacity and are capable of being intercalated with an organic cation between the silicate layers. This reaction is based on the ion exchange of exchangeable inorganic ions (Na + , K + , etc.) in the layered clay minerals. In this study, we examined the properties of synthetic mica, whose silicate layers were intercalated with a cationic organic compound (dioctadecyl dimethyl ammonium chloride). We evaluated the lubrication performance of the mica using a newly devised upsetting-ironing type tribometer. X-ray diffraction (XRD) results show that the distance between the silicate layers of the intercalated synthetic mica increased to 36.6 A from 12.6 A for a non-intercalated one. Owing to the increase in the interlayer distance, the lubrication coating containing the synthetic mica-organic intercalation compound showed a much improved lubrication performance than that of the non-intercalated one. These findings indicate that the lubricity of the clay minerals is highly dependent on the friction between the different silicate layers, and that the cationic organic compound incorporated into the interlayers can improve the lubricity. This result means that the clay-organic intercalation compound is a promising solid lubricant as an alternative to MoS 2 .

It is well known that the surface roughness of metal substrates considerably influences the tribological properties of solid lubricants. In this study, the surfaces of metal substrates were modified by wet-blasting and polishing, and the lubrication performance of synthetic mica-organic intercalation compounds on these substrates was evaluated using an upsetting-ironing type tribometer. Wet-blasted substrates lubricated with synthetic mica exhibited the best anti-seizure ability, whereas a lubricated polished metal surface produced the worst results. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS) revealed that concavities prepared by wet-blasting still remained on the ironed substrate surface, and the intercalated synthetic mica trapped in concavities was supplied to the flat areas as ironing advanced across the substrate surface. Furthermore, EDS and Fourier-transform infrared spectroscopy (FTIR) analysis showed that intercalated synthetic mica extended on the ironed surface while releasing organic compounds from its interlayer spaces. As the ironing process continued to progress, the initial concavities gradually became shallow, but they did not completely flatten. Therefore, a roughened surface is more advantageous for achieving improved lubricity due to the continuous supply of solid lubricant from concavities to the flattened areas where seizure is likely to take place.

This chapter examines the experiences of African American women who were stationed in various parts of mainland Japan under U.S. military occupation from 1945 to 1952 as major actors in shaping the postwar U.S.-Japanese relationship. It argues that African American women in Japan defined, asserted, and performed alternative racial identities, gender roles, and class positions to achieve their own empowerment within the “transpacific” boundaries they encountered as “occupiers” in Japan, as well as racial and gender minorities in the U.S. military and the larger American society. It also challenges the so-called Master Narrative of the Civil Rights Movement by focusing on the “transpacific” struggles of the African American women in occupied Japan for racial and gender equality and justice.

The existence of new vector-like quarks is often predicted by models of new physics beyond the Standard Model, and the development of discovery strategies at colliders is the object of an intense effort from the high-energy community. Our analysis aims at identifying the constraints on and peculiar signatures of simplified scenarios containing \textit{two} vector-like quark doublets mixing with \textit{any} of the SM quark generations. This scenario is a necessary ingredient of a broad class of theoretically motivated constructions. We focus on the two charge $2/3$ states $t_{1,2}^\prime$ that, due to their peculiar mixing patterns, feature new production and decay modes that are not searched for at the LHC: single production of the heavier state can dominate over the light one, while pair production via electroweak interactions overcomes the QCD one for masses at the TeV scale., Comment: 29 pages, 20 figures

Ribosome biogenesis and turnover are processes necessary for cell viability and proliferation, and many kinds of proteins are known to regulate these processes. However, many questions still remain, especially in the Archaea. Generally, several ribonucleases are required to process precursor rRNAs to their mature forms, and to degrade rRNAs for quality control. Here, we found that FAU-1, which is known to be an RNA binding protein, possesses an RNase activity against precursor 5S rRNA derived from P. furiosus and T. kodakarensis in the order Thermococcales in vitro. An in vitro analysis revealed that UA sequences in the upstream of 5S rRNA were preferentially degraded by addition of FAU-1. Moreover, a fau-1 gene deletion mutant of T. kodakarensis showed a delay of exponential phase, reduction of maximum cell number and significant changes in the nucleotide sequence lengths of its 5S, 16S, and 23S rRNAs in early exponential phase. Our results suggest that FAU-1 is a potential RNase involved in rRNA stability through maturation and/or degradation processes.

We have earlier showed how the catalytic conversion of 1,2-propandiol to propanal using FSM-16 (#16 folded sheets of mesoporous materials) when molded by wet treatment proceeded more favorably than when using FSM-16 molded by pressurization, while no comparison using other typical acidic catalysts and no examination of the acidic properties of FSM-16 was carried out. In the present study, the conversion using FSM-16 molded by wet treatment and pressurization was compared with that obtained by using typical acidic catalysts such as SiW12O40/SiO2 and MCM-41 (#41 of Mobil Composition of Matter) together with amorphous SiO2. Among these catalysts, FSM-16 molded by wet treatment showed the most suitable catalytic activity. In order to examine the effect of the molding procedure for FSM-16 on its structural and acidic properties, FSM-16 molded by both methods was examined using NH3-TPD, in situ FT-IR using NH3 as a probe molecule, and Hammett indicators together with XRD and TEM. According to Zaitsev's rule, the present conversion should afford acetone rather than propanal, which indicates that it would proceed via hydro cracking. Therefore, the conversion of 1,2-propandiol using FSM-16 was also examined in the presence and absence of hydrogen. Furthermore, hydration reactions of 1- and 2-propanol when using FMS-16 were examined. Based on the results obtained from this investigation, it was concluded that the conversion using a more acidic FSM-16 molded by wet treatment proceeded through dehydration rather than through hydro cracking.

This paper presents design study on windage loss reduction for hybrid excitation flux switching motor employing two types of rotor structure. Conventional flux switching motors have a rotor structure with salient poles, by which windage loss at high speed region becomes serious. To reduce the windage loss, two types rotor are built: One is a cylindrical rotor employing iron rib between adjacent salient poles and shrouds placed at both ends in axial direction of rotor body and, the other is only employing the shrouds. Experimental tests using two machines combining with an existing stator and two rotors are conducted. As a result, the rotor with only the shrouds can greatly reduce the windage loss while keeping the maximum torque and power, and motor efficiency at high speed region as it is. From a viewpoint of windage loss reduction, different rotor configurations with and without the shroud are investigated by 3D-FEA based fluid analyses and discussed.

The catalytic conversion of 1,2-propandiol to propanal is examined using FSM-16 particles (0.85－1.70 mm) molded by wet-treatment and pressurization. When FSM-16 was molded with 0.6 g of pressurization and supplied to the catalytic conversion of 1,2-propandiol at 673 K, this system resulted in a 94.8% conversion of 1,2-propandiol and 90.5% selectivity to propanal at 0.25 h on-stream, which was the maximum amount of activity. However, at 4.50 h on-stream, the activity decreased extremely to deactivation 19.9% conversion of 1,2-propandiol and 84.7% selectivity to propanal. In contrast, when FSM-16 molded with wet-treatment (0.15 g) was used for the conversion at 573 K, activity was greatly increased and stable 98.6% conversion of 1,2-propandiol and 56.2% selectivity to propanal at 0.25 h on-stream followed by 91.9% and 52.5%, respectively, at 4.50 h on-stream. The hexagonal structure of FSM-16 was suggested to have contributed to the suitable conversion of 1,2-propandiol to propanal.

In this paper, we report a newly developed compact model HiSIM-GaN [Hiroshima University STARC IGFET Model for GaN high electron mobility transistors (HEMTs)] including a capacitance model, which accurately captures the contributions originating from the device's field plate (FP) structure. The capabilities of the reported model are demonstrated by reproduction of the measured power efficiency of a boost converter circuit, enabled through separate extraction of the parasitic FP contributions. In addition, physical trap-density modeling is verified to be also of key importance for accurate prediction of the power efficiency.

In February 1947, the all-black 24th Infantry Regiment was relocated from Okinawa to mainland Japan to join the occupation forces of the U.S. Army as part of the 25th Infantry Division. The 24th Infantry Regiment was stationed at Camp Majestic in Gifu, which is located 270 miles southwest of Tokyo in central Japan. (1) It was there that African American soldiers, as representatives of the Allied occupation forces, would have their first extensive face-to-face contact with Japanese citizens. Ironically, African American occupation soldiers, whose major mission in Japan was to democratize the defeated nation and disseminate the values of freedom and equality among the Japanese population, served in a segregated U.S. Army. This essay examines the early postwar encounters of African American soldiers, many of whom served in the 24th Infantry Regiment, with Japanese citizens around Camp Gifu under U.S. military occupation during the period from 1947 to 1951. (2) African American GIs in Japan explored and enhanced the racial and gendered sense of justice, power, and identity within the boundaries of the privileged status that they enjoyed as members of the U.S. occupation forces as well as the racial discrimination that they encountered both in the U.S. Army and Japanese society after the end of the Second World War. The "trans-Pacific interaction" of the racial-sexual ideology and practices surrounding black masculinity were central to the formation of racial, gendered, and national subjectivities among African American GIs in occupied Japan. In seeking out eyewitness and other accounts, I consulted the oral history collection at the U.S. Army Center of Military History, major black newspapers and magazines, the NAACP papers, U.S. military records, and autobiographies and memoirs written by African American GIs and Japanese residents in the area around Camp Gifu. (3) This study illuminated how African American soldiers grappled with the terms of military occupation, race relations, national belonging, and gender/sexual norms in their encounters with the Japanese in Gifu. In occupied Gifu, African American soldiers reconsolidated, reconstructed, and complicated their sense of "American-ness," "blackness," and notions of masculinity through their daily personal encounters and exchanges with local Japanese women and men. The overseas military experience in Japan, the defeated "non-white nation" that African Americans had admired as their racial ally before the war, encouraged African American GIs to reconfigure their racial identity beyond the domestic context of racial oppression and discrimination found in the United States. African American soldiers, like white GIs, asserted and performed the "victorious" American masculinity in their romantic and sexual relationships with Japanese women by invoking influential U.S. orientalist representations of Japanese femininity. Some African American GIs further developed their fraternization with Japanese women into marriage and childbearing and confronted the institutional, organizational, and ideological barriers against interracial intimacy and sexuality in both Japan and the United States. This analysis is built upon the historiography of African American military experiences, African American-Japanese relationships, and the postwar U.S. military engagement in Japan. Most historical studies of the African American-Japanese relationship have investigated how black intellectual and political leaders forged interracial solidarity with the Japanese, or critiqued Japan's imperialist aggression in Asia within the parameters of the black global struggle against white supremacy, as well as the U.S.-Japanese relationship during the first half of the 20th century. (4) The centrality of race and nation as analytical categories in these earlier studies of the pre-war African American-Japanese relationship usually ignored the gender and sexual dynamics of the "trans-Pacific exchanges" between African Americans and the Japanese. …

構成：塚﨑朝子

A micro-electro-mechanical-system internal combustion engine (MEMS IC engine) is fabricated to demonstrate the energy conversion from heat to mechanical power. The dimensions and surface-to-volume ratio of combustion chamber are 5 mm × 3 mm × 1 mm (0.015 cc) and 3.07 mm −1 , respectively. The reciprocation motion of a piston can be sustained by the force balance between combustion pressure and the repulsion force of an elastic spring. A premixture gas composed of hydrogen and oxygen is used for fuel under stoichiometric combustion (equivalent ratio is 1). The combustion is confirmed by pressure measurement and the direct observation of flame propagation. A high-speed CMOS camera is adopted for the flame observation. A maximum combustion pressure of 142.6 kPa, a displacement of 9.5 mm 3 , and a mechanical power of 29.1 mW were obtained for the MEMS IC engine. This experimental evidence provides a positive outlook for the materialization of the MEMS heat engine concept.

Physics at the international linear collider (ILC) is described as an introductory talk at Linear Collider Workshop 2006 (LCWS06).

OBJECTIVE To examine the immunoreactivity of tumors for matrix metalloproteinases 2 and 9 (MMP-2, MMP-9), tissue inhibitors of metalloproteinases 1 and 2 (TIMP-1, TIMP-2), and membrane type MMP 1 (MT-MMP-1), to evaluate the optimum assessment of incidental renal cell carcinoma. METHODS Tumor samples from 120 incidental clear cell renal cell carcinoma (ICRCC) patients without distant metastasis or invasion beyond Gerota's fascia were obtained by surgery. They were immunohistochemically stained for MMP-2, MMP-9, TIMP-1, TIMP-2, and MT-MMP-1. Immunoreactivity for these factors was analyzed by semiquantitative multivariate analysis for cancer-specific survival. RESULTS The cancer-specific 5 and 10-year survival rates were 91.4% and 91.4%, respectively. Univariate analysis revealed that nuclear grade (P = 0.0064) and TIMP-2 (P = 0.034) were significant prognostic factors. Matrix metalloproteinase 9 has a significant relationship with high nuclear grade RCC (P = 0.017) and was found to be an independent prognosticator by Cox multiple regression analysis (P = 0.0028). CONCLUSIONS Nuclear grade and TIMP-2 were significant prognostic factors of ICRCC. Multivariate analysis showed that a nuclear grade greater than 3 was associated with a 566% significant increase in the odds of cancer death. Strong expression of MMP-9 was associated with a 774% increase in the odds of high nuclear grade, with statistical significance. Although ICRCC is well known for having a favorable prognosis, patients with tumors having a high nuclear grade and strongly expressed MMP-9 and TIMP-2 should undergo strict postoperative follow-up.

Mechanical loss (internal friction) in cubic zirconia was measured in the flexural mode in order to understand the local structure associated with oxygen vacancy. Polycrystal and single crystal with different orientation of longitudinal axis (〈100〉, 〈110〉, 〈111〉) were adopted from 8 mol.% Y2O3 stabilized zirconia (8Y-FSZ), which shows that the internal friction profile depends on crystal orientation. In the present study, furthermore, anelastic strain behavior was also investigated in the single crystal specimens. Anelastic strain productivity is also strongly dependent on crystal orientation like internal friction: 〈100〉 < 〈110〉 < 〈111〉. It is considered that the crystal orientation dependence of internal friction and anelasticity is closely correlated with the behavior of cation–oxygen vacancy complexes. Finally, the mechanism of anelasticity was discussed.

A compact model of GaN HEMT is developed, which solves the Poisson equations explicitly. The model includes all possible charges induced within the device including the trap density. It is verified that the model can reproduce all 2D-device simulation results accurately. In particular, the operation frequency dependence of the current collapse can also be captured accurately by adjusting the trap time constant.

This paper summarizes investigations for the carrier-trapping influence on electric characteristics of MOSFETs. Particular focus is given on the transient characteristics, which is affected by the time constant of the carrier trapping during the device operation. For the purpose a compact model has been developed for circuit simulation by considering the dynamic trap/detrap feature in the framework of the complete surface-potential description in HiSIM. It is demonstrated that the trap-density model considers the trap/detrap time constant enables to simulate not only frequency dependent switching characteristics accurately but also long-term device degradation.

We study the lepton flavor violation in the supersymmetric seesaw model taking into account recent experimental improvements, especially for the Higgs boson mass measurement, direct searches of superpartners and the rare decay of B_s -> mu+ mu- at the LHC, the neutrino mixing angle of theta_{13} at the neutrino experiments, and the search of mu -> e gamma at the MEG experiment. We obtain the latest constraints on the parameters in the supersymmetry breaking terms and study the effect on the lepton flavor violating decays of tau -> mu gamma and mu -> e gamma. In particular, we consider two kinds of assumption on the structures in the Majorana mass matrix and the neutrino Yukawa matrix. In the case of the Majorana mass matrix proportional to the unit matrix, allowing non-vanishing CP violating parameters in the neutrino Yukawa matrix, we find that the branching ratio of tau -> mu gamma can be larger than 10^{-9} within the improved experimental limit of mu -> e gamma. We also consider the neutrino Yukawa matrix that includes the mixing only in the second and third generations, and find that a larger branching ratio of tau -> mu gamma than 10^{-9} is possible with satisfying the recent constraints., 25 pages, 7 figures