Topological Edge and Corner States in Biphenylene Network

The electronic states and topological properties of the biphenylene network (BPN) are analyzed using a tight-binding model based on the $\pi$-electron network. It is shown that tuning the hopping parameters induces topological phase transitions, leading to the emergence of edge states owing to the nontrivial topological Zak phase of the bulk BPN. Elementary band analysis clearly gives the number of edge states, which are associated with the location of Wannier centers. In addition, we have presented the conditions for the emergence of corner states owing to the higher-order topological nature of BPN.Comment: 11 pages, 10 figure

A 100 W-Class Water-Vapor Hall Thruster for Constellations and Space Explorations by SmallSats

The laboratory models of a water-vapor Hall thruster and LaB6 thermionic cathode were developed and tested. To optimize the thruster design to water-vapor propellant, the geometrical investigation was conducted. After testing six different models, the smallest thruster, with an outer diameter of 20 mm, was found to be the most suitable for 100-W class operation. This thruster was able to be operated less than 100 W at 200 V. In addition, the discharge power was suppressed to 200 W even at 300 V. Based on the plume diagnostics, the thrust force of 2.9 mN, specific impulse of 650 s, and anode efficiency of 4.6 % were obtained as a representative performance of this 300 V operating point. After the thruster operation was achieved, the cathode coupling test was conducted to demonstrate electron emission under water-vapor plasma existence. As a result of this experiment, the effective increase in electron current compared to the previous stand-alone tests was confirmed as well as the compatability to the water-vapor plasma plume. On the other hand, the electron emission current has not achieved 100 mA-class yet and the required heating power was predicted over 100 W; thus, further improvement is progressing

Acute liver failure due to herpes simplex viral hepatitis diagnosed by skin lesions and blood tests: a case report

Abstract Background The incidence of acute liver failure from herpes simplex virus is rare. Case presentation A 71-year-old Japanese man was diagnosed with acute liver failure and was transferred to our hospital. Steroid therapy, plasma exchange, and hemodiafiltration were started for liver failure, and antimicrobial therapy was initiated for pneumonia. Staphylococcus epidermidis was detected in blood culture. Skin rash appeared; a positive anti-herpes simplex virus result led to the diagnosis of acute liver failure from herpes simplex virus. Hence, acyclovir was started. After blood tests improved, treatments for acute liver failure were discontinued. Antimicrobial therapy was continued; however, he died. In this case, persistent bacteremia and drug-induced liver damage due to acyclovir may have contributed to his death. Conclusions Acute liver failure can lead to complications and death. Thus, careful observation is crucial, even if the patient has shown some improvements

A Case of Spurting Bleeding After Endoscopic Papillary Balloon Dilation

A 58-year-old male with acute cholangitis due to a common bile duct stone underwent endoscopic retrograde cholangiopancreatography for stone removal with endoscopic papillary balloon dilation (EPBD) due to his high bleeding risk owing to maintenance dialysis and antiplatelet and anticoagulant medications. He had a history of stone removal using an EPBD. The stone was removed; however, the patient subsequently developed spurting bleeding and underwent endoscopic hemostasis. Despite the subsequent mild pancreatitis, he recovered with conservative management. While EPBD is considered a low-risk procedure for bleeding, caution should still be exercised due to the possibility of massive postprocedural bleeding

Antibiotic Administration within Two Days after Successful Endoscopic Retrograde Cholangiopancreatography Is Sufficient for Mild and Moderate Acute Cholangitis

To prevent the increase of resistant bacteria, it is important to minimize the use of antimicrobial agents. Studies have found that administration for ≤3 days after successful endoscopic retrograde cholangiopancreatography (ERCP) is appropriate. Therefore, the present study aimed to verify if administration of antimicrobial agents can be further shortened to ≤2 days after ERCP. We divided 390 patients with mild and moderate cholangitis who underwent technically successful ERCP from January 2018 to June 2020 and had positive blood or bile cultures into two groups: antibiotic therapy within two days of ERCP (short-course therapy, SCT; n = 59, 15.1%), and for >3 days (long-course therapy, LCT; n = 331, 84.9%). The increased severity after admission and other outcomes were compared between the two groups, and the risk factors for increased severity were verified. There were no between-group differences in patient characteristics. Total length of hospital stay was shorter in SCT than in LCT, and other outcomes in SCT were not significantly different from those in LCT. Being 80 or older was a risk factor for increased severity; however, SCT was not associated with increased severity. Antimicrobial therapy for ≤2 days after successful ERCP is adequate in patients with mild and moderate acute cholangitis