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Introduction The aim of this study was to investigate the validity of the duration for which we provide antibiotic prophylaxis to maxillofacial fracture patients who undergo open reduction and internal fixation (ORIF) in our hospital by retrospectively reviewing the incidence of surgical site infections (SSIs). Methods The medical records of 83 patients with maxillofacial fractures who underwent ORIF from April 2010 to October 2019 were retrospectively reviewed. The surgeon selected the proper surgical approach to the fracture site depending on the location and type of fractures. ORIF was performed by an intraoral, extraoral, or transconjunctival approach, or a combination of these approaches. No statistical investigation of differences in the method of prophylactic antibiotic administration and the occurrence of SSIs was conducted because of the small sample size. Results This retrospective study included 81 patients (58 males; median age 41 (range: 13–82) years; median BMI 22.4 (range: 16.5–33.6) kg/m2) with maxillofacial fractures. Two patients with infected fractures before operation withdrew from this study. The most common choice of antibiotic prophylaxis was cefmetazole for 2 days, followed by cefmetazole for 1 day. Two patients were diagnosed with an SSI; one was on cefazolin 2 g for 2 days, and the other was on cefmetazole 2–4 g for 2 days. In both cases the infection was successfully controlled, and implant removal was not required. Conclusions In principle, antibiotic prophylaxis for 2 days postoperatively is sufficient in ORIF for maxillofacial fracture, but a multicenter, prospective, randomized study may be required to confirm this.

Background Scallop shell powder is called bioshell calcium oxide (BiSCaO), which is known to possess deodorizing properties and broad antimicrobial activity against various pathogenic microbes, including viruses, bacteria, spores, and fungi. Objective This study aims to investigate the applications of BiSCaO suspension cleansing in clinical situations, for instance for the prevention and treatment of infections in chronic wounds in healing-impaired patients, without delaying wound healing. Methods The bactericidal activities of 1000 ppm BiSCaO suspension; 500 ppm hypochlorous acid; 1000 ppm povidone iodine; and saline were compared to evaluate in vivo disinfection and healing of Pseudomonas aeruginosa-infected wounds in hairless rats. Results Cleansing of the infected wounds with BiSCaO suspension daily for 3 days significantly enhanced wound healing and reduced the in vivo bacterial counts, in comparison to hypochlorous acid, povidone iodine, and saline. Furthermore, histological examinations showed significantly advanced granulation tissue and capillary formation in the wounds cleansed with BiSCaO suspension than in those cleansed with the other solutions. Conclusions This study suggested that the possibility of using BiSCaO suspension as a disinfectant for infected wounds and limiting disinfection to 3 days may be sufficient to avoid the negative effects on wound repair.

Bioshell calcium oxide (BiSCaO) possesses deodorizing properties and broad microbicidal activity. This study aimed to investigate the application of BiSCaO ointment for the prevention and treatment of infection in chronic wounds in healing-impaired patients, without delaying wound healing. The bactericidal activities of 0.04, 0.2, 1, and 5 wt% BiSCaO ointment, 3 wt% povidone iodine ointment, and control (ointment only) were compared to evaluate the in vivo disinfection and healing of Pseudomonas aeruginosa-infected wounds in hairless rats. Treatment of the infected wounds with 0.2 wt% BiSCaO ointment daily for 3 days significantly enhanced wound healing and reduced the in vivo bacterial counts compared with povidone iodine ointment and control (no wound cleaning). Although 5 wt% BiSCaO ointment provided the lowest bacterial counts during 3 days&rsquo, treatment, it delayed wound healing. Histological examinations showed significantly advanced granulation tissue and capillary formation in wounds treated with 0.2 wt% BiSCaO ointment for 3 days compared to wounds treated with the other ointments. This study suggested that using 0.2 wt% BiSCaO ointment as a disinfectant for infected wounds and limiting disinfection to 3 days may be sufficient to avoid the negative effects of BiSCaO on wound repair.

The importance of protecting the eyes from infectious agents in patients’ blood and saliva during dental surgery has long been known, but the global COVID-19 pandemic has made this even more important. The use of ATP bioluminescence to investigate the contamination of dental goggles during the surgical removal of impacted teeth in the present study indicates their importance for protecting the eyes from aerosols from the front, from above, and from the sides.

The excitonic insulator is an intriguing correlated electron phase formed of condensed excitons. A promising candidate is the small band gap semiconductor Ta2NiSe5. Here we investigate the quasiparticle and coherent phonon dynamics in Ta2NiSe5 in a time resolved pump probe experiment. Using the models originally developed by Kabanov et al. for superconductors, we show that the material's intrinsic gap can be described as almost temperature independent for temperatures up to about 250 K to 275 K. This behavior supports the existence of the excitonic insulator state in Ta2NiSe5. The onset of an additional temperature dependent component to the gap above these temperatures suggests that the material is located in the BEC-BCS crossover regime. Furthermore, we show that this state is very stable against strong photoexcitation, which reveals that the free charge carriers are unable to effectively screen the attractive Coulomb interaction between electrons and holes, likely due to the quasi one-dimensional structure of Ta2NiSe5., 27 pages, 8 figures

In this study, we examine exposure characteristics of a positive tone electron beam resist consisting of methyl α- chloroacrylate and α-methylstyrene by changing the development process conditions. 25/25 nm and 30/30 nm line-andspace (L/S) patterns (design value) are developed in amyl and heptyl acetates. The resist patterns developed at 0oC for 120 s show the better shapes having the vertical sidewalls than those developed at 22 °C for 60 s. The dose margins of pattern formation for 0°C development become wider, although the sensitivities are lower. The effect of post exposure baking (PEB) on exposure characteristics is also investigated. Adding PEB process performed at 120°C for 2 min, the dose margin also becomes wider although the sensitivity is lower. 20/20 nm L/S patterns are fabricated by using PEB and/or 0°C development. Though the required exposure dose is larger, the resist pattern is improved by PEB and/or 0°C development. The formation of 35 nm pitch pattern is also presented.

The excitonic insulator is an intriguing electronic phase of quasi-condensed excitons. A prominent candidate is the small bandgap semiconductor Ta2NiSe5, in which excitons are believed to undergo a BEC-like transition. But experimental evidence for the existence of a coherent condensate in this material is still missing. A direct fingerprint of such a state would be the observation of its collective modes, which are equivalent to the Higgs- and Goldstone-modes in superconductors. Here we report evidence for the existence of a coherent amplitude response in the excitonic insulator phase of Ta2NiSe5. Using non-linear excitations with short laser pulses we identify a phonon-coupled state of the condensate that can be understood as a coupling of its electronic Higgs-mode to a low frequency phonon. The Higgs-mode contribution substantiates the picture of an electronically driven phase transition and characterizes the transient order parameter of the excitonic insulator as a function of temperature and excitation density., Comment: 32 pages, 12 figures, 1 table

Higher resolution is eagerly requested to the electron beam resist for the next generation photomask production as well as higher sensitivity. The performance of a polymer resist is mainly characterized by its chemical structure and molecular weight. Positive tone polymer resists with various molecular weights ranging from 60 k to 500 k are synthesized and the molecular weight dependence on exposure characteristics is examined by fabricating line-and-space patterns. The molecular weight dependence of sensitivity for amyl acetate developer is small in the molecular weight range in this study. In a low molecular weight resist, the cross-section profile of the resist pattern becomes rounder and then the disconnections are observed in the 20-nm line-and-space pattern. Although the pattern width change by changing the exposure dose for each resist is quite similar, the exposure dose margin of pattern formation becomes wider with the higher molecular weight. The line width roughness is smaller in a high molecular weight resist than in a low molecular weight resist. The shift amount of the pattern width from the design value for various line-and-space patterns and the dry etching resistance to CF 4 plasma are also presented.

従来の鉄道高架橋には, 主に経済性の観点から鉄筋コンクリート構造のラーメン高架橋が多く用いられている. 一方, 施工環境の厳しい条件下では, 型枠, 配筋等の現場作業を省略することができれば, 施工の安全性の向上と全体工費の低減が期待できる. コンクリート充填鋼管を柱部材とした複合構造の鉄道ラーメン高架橋は, 鋼管を型枠として使用できることから施工の簡素化, および工期短縮が可能であり, 加えて, 鋼とコンクリートの合成効果により高い耐震性能が得られる. 本報文は, このような複合構造の鉄道ラーメン高架橋を対象に, 筆者らがすでに提案した部材の耐荷性能の評価手法を用いて大規模地震に対する構造物の安全性の照査例を示したものである.

In the recently deregulated electricity market, a more secure of power system operation is essential. One of the methods to avoid the risk of compromising power system instability is preventive control which often comes in the form of generation rescheduling. This paper attempts to solve transient stability preventive control problem by generation redispatch utilizing the Primal-Dual Interior Point Method (PDIPM) Non Linear Programming (NLP) Transient Stability Constrained Optimal Power Flow (TSCOPF). A linear cost model is derived to accommodate generation redispatch. Our simulation shows that the proposed method is able to solve the transient stability preventive control problem by rescheduling necessary active power generation.