Time-Resolved Fuel Density Profiles of the Stagnation Phase of Indirect-Drive Inertial Confinement Implosions.

The implosion efficiency in inertial confinement fusion depends on the degree of stagnated fuel compression, density uniformity, sphericity, and minimum residual kinetic energy achieved. Compton scattering-mediated 50-200 keV x-ray radiographs of indirect-drive cryogenic implosions at the National Ignition Facility capture the dynamic evolution of the fuel as it goes through peak compression, revealing low-mode 3D nonuniformities and thicker fuel with lower peak density than simulated. By differencing two radiographs taken at different times during the same implosion, we also measure the residual kinetic energy not transferred to the hot spot and quantify its impact on the implosion performance.

Adverse effects of long-term drain placement and the importance of direct aspiration: a retrospective cohort study.

BACKGROUND: Long-term placement of prophylactic drains may result in retrograde infections. AIM: To investigate the association between the timing of drain removal and clinical outcomes. METHODS: This retrospective, single-centre cohort study evaluated 110 patients who underwent elective gastrointestinal or hepatopancreatobiliary surgery and developed subsequent organ/space surgical site infection (SSI) between 2016 and 2020. The difference between the culture-positive species of prophylactic drains and direct aspiration was evaluated; whether the prophylactic drains functioned effectively at the time of SSI diagnosis; and whether the empirical antibiotics administered before drainage were effective against all the detected bacteria. Finally, clinical outcomes were compared between early (i.e. cases wherein the prophylactic drain had already been removed or replaced at the time of SSI diagnosis) and late (removal after diagnosis) drain removal. FINDINGS: The prophylactic drains functioned effectively in only 27 (25%) patients at the time of SSI diagnosis. Due to the results of direct aspiration cultures, 43% of patients required antibiotic escalation. The median time to drain removal or first replacement was seven postoperative days. The early removal group included 43 patients (39%). Compared with early removal, late removal resulted in a higher frequency of vancomycin use (7.0% vs 22.4%; P = 0.037). CONCLUSION: Prolonged prophylactic drain placement is associated with complicated infections requiring vancomycin; therefore, the drains should be removed as soon as possible. Additionally, obtaining the cultures of direct aspiration should be actively considered, as escalation of antimicrobial therapy is often performed based on culture results.

Establishment of a model experiment system to elucidate the mechanism by which Zn-protoporphyrin IX is formed in nitrite-free dry-cured ham.

The aim of this study was to establish a model experiment system to elucidate the mechanism by which Zn-protoporphyrin IX (ZPP) is formed in Parma ham. The established model consisted of myoglobin, meat and antibiotics, and incubation under anaerobic conditions resulted in a greater yield of ZPP. Formation of ZPP was observed even in the presence of various antiseptics. The amount of ZPP formed increased as the period of incubation increased. ZPP formation was inhibited by heating meat homogenate depending on the heating temperature. Our results show that anaerobic conditions are suitable for the formation of ZPP in meat products without nitrate or nitrite and that endogenous enzymes as well as microorganisms may be involved in ZPP formation.