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Preceding a core-collapse supernova (CCSN), various processes produce an increasing amount of neutrinos of all flavors characterized by mounting energies from the interior of massive stars. Among them, the electron antineutrinos are potentially detectable by terrestrial neutrino experiments such as KamLAND and Super-Kamiokande (SK) via inverse beta decay interactions. Once these pre-supernova (pre-SN) neutrinos are observed, an early warning of the upcoming CCSN can be provided. In light of this, KamLAND and SK, both located in the Kamioka mine in Japan, have been monitoring pre-SN neutrinos since 2015 and 2021, respectively. Recently, we performed a joint study between KamLAND and SK on pre-SN neutrino detection. A pre-SN alert system combining the KamLAND detector and the SK detector was developed and put into operation, which can provide a supernova alert to the astrophysics community. Fully leveraging the complementary properties of these two detectors, the combined alert is expected to resolve a pre-SN neutrino signal from a 15 M ⊙ star within 510 pc of the Earth at a significance level corresponding to a false alarm rate of no more than 1 per century. For a Betelgeuse-like model with optimistic parameters, it can provide early warnings up to 12 hr in advance.

Particle dark matter could belong to a multiplet that includes an electrically charged state. WIMP dark matter (χ0) accompanied by a negatively charged excited state (χ−) with a small mass difference (e.g. < 20 MeV) can form a bound-state with a nucleus such as xenon. This bound-state formation is rare and the released energy is O(1−10) MeV depending on the nucleus, making large liquid scintillator detectors suitable for detection. We searched for bound-state formation events with xenon in two experimental phases of the KamLAND-Zen experiment, a xenon-doped liquid scintillator detector. No statistically significant events were observed. For a benchmark parameter set of WIMP mass mχ0=1 TeV and mass difference Δm=17 MeV, we set the most stringent upper limits on the recombination cross section times velocity 〈σv〉 and the decay-width of χ− to 9.2×10−30 cm3/s and 8.7×10−14 GeV, respectively at 90% confidence level.

In this study, changes in maritime traffic flow due to the installation of virtual buoys were analysed from the perspective of collision, based on the obstacle zone by target (OZT) method. The existence of an OZT within ±2° in the bow direction is considered to be dangerous; all the OZTs that a vessel encountered at the time when this orientation prevailed were subjected to analysis. For the calculation of the OZT model, an SD3 model was used. The estimated OZT was used to calculate the OZT density, and the positions of the ships that were encountering the OZT were used for the analysis. It was found that the OZT density at the locations where collisions had occurred in the past was approximately 0.01 [times/km2]. After the installation of virtual buoys, most places around there were reduced to around approximately 0.005 [times/km2]. The results imply that the installation of virtual buoys has reduced the risk of collisions. In contrast, the OZT density in the southern region of Buoy 1 increased from approximately 0.005 [times/km2] to approximately 0.01 [times/km2], suggesting that a more detailed analysis of this area is required. [ABSTRACT FROM AUTHOR]

A complete grasp of the actual vessel traffic flow by accurate observation is essential to carry out vessel traffic management, design of vessel traffic route, plan of port construction, etc. Up to now, the observation of vessel traffic has needed many efforts such as the use of a special ship or car equipped with radar observation systems and the observation staff preparation for a considerably long period. In order to perform accurate observation of vessel traffic without such efforts, the authors have developed a completely automated radar network system covering the main traffic route of Tokyo Bay. In August 2003, as the second remote radar station attaching AIS equipment was set at East Ogishima (the first was installed at the National Defense Academy in 2002), the observing range could be enlarged and cover most traffic routes in Tokyo Bay. These two radars can observe the vessel traffic in Tokyo Bay simultaneously so as to know the traffic flow accurately on the basis of analyzing the integrated radar data. In addition to the development of a radar network system, the software to analyze observed vessel traffic flow has been developed. This software has various functions such as tracking of ship's position, automatic determination of ship's size, animation of ship's movements, superposition of successive radar images, display of ship's tracks, calculation of ship's speed distribution, extraction of dangerous ship encounters using subjective judgment value and bumper model, etc. Some analyzed results on vessel traffic flow observed by the remote radars in January and September 2003 are shown in this paper. [ABSTRACT FROM PUBLISHER]

Competing Interests: Declaration of Competing Interest The all authors declare that they have no conflict of interest.

A minimally invasive approach using laparoscopy or robotics has become the standard procedure in surgery for colorectal cancer. However, obesity is considered to be associated with a poor prognosis in laparoscopic colorectal surgery. Perioperative management, as well as the surgical procedure, is particularly important in severely obese patients. A case of colon cancer with severe obesity that underwent laparoscopic colectomy and was managed safely by multidisciplinary perioperative management in collaboration with a bariatric and metabolic surgery (BMS) team is presented. The patient was severely obese, with a body mass index (BMI) of 50.4 kg/m 2 . After one month of preoperative weight loss intervention by the BMS team, the patient's weight was successfully decreased by approximately 15 kg (BMI: 46 kg/m 2 ), and the patient underwent laparoscopic colectomy for transverse colon cancer in collaboration with the BMS team. In the laparoscopic surgery, a small incision for specimen removal was made above the umbilicus to insert the first trocar safely, and five additional trocars, whose placement was determined based on the target vessels of the dissected lymph nodes in reference to preoperative computed tomography (CT), were also inserted above the umbilicus. Gastrointestinal reconstruction was performed intracorporeally by an overlap technique using an endoscopic linear stapler to perform the procedure safely with minimal invasiveness. The patient was discharged on postoperative day eight without any postoperative complications, following early postoperative rehabilitation with intervention by the BMS team. The proportion of colorectal cancer patients with obesity is expected to increase in the future, and the establishment of multidisciplinary perioperative management and surgical techniques will be useful to improve the surgical outcomes and prognosis of colorectal cancer patients with severe obesity., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: Yuki Matsumi declare(s) a grant from JSPS KAKENHI, grant number JP24K19391. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Matsumi et al.)

Background: Myeloid sarcoma (MS) is an extramedullary tumor constituted by myeloid blasts or immature myeloid cells. It frequently occurs in conjunction with acute myeloid leukemia (AML); however, it can exceptionally manifest in patients without leukemia. Here, we present a rare case of primary MS originating in the small bowel without evidence of bone marrow involvement., Case Representation: A 33 year-old female with no relevant medical history was admitted to our hospital with recurrent abdominal pain. Computed tomography (CT) revealed bowel obstruction due to thickening of the ileum wall, which was suspected to be an ileal tumor. Initially, ectopic endometriosis was suspected because of abdominal pain associated with the menstrual cycle and changes observed on a follow-up CT scan. The lesion could not be detected by double-balloon endoscopy. Despite conservative treatment, the obstruction persisted, and laparoscopic partial ileal resection was performed, which revealed extensive involvement of the ileum and mesentery. Additionally, the mesentery of the resected ileum was extremely thickened. Histopathological and immunohistochemical examinations of the surgical specimen indicated ileal MS. Bone marrow aspiration after discharge was negative for cytological findings of leukemia, leading to a final diagnosis of primary ileal MS. Her postoperative course was uneventful, and she is currently undergoing systemic chemotherapy tailored to AML at another hospital., Conclusions: Even though MS of the small bowel is rare and may not be considered preoperatively, similar surgical treatment to that of other small bowel malignancies can ensure proper postoperative diagnosis and appropriate chemotherapy. Given the potential need for chemotherapy, ensuring surgical safety that allows for its rapid initiation is critical., (© 2024. The Author(s).)

Study Design: Retrospective cohort study., Purpose: This study aimed to demonstrate the advantages of preservation of the lumbosacral segment (LSS) in adult spinal deformity (ASD) surgery., Overview of Literature: Sacroiliac foundation enables sufficient restoration in ASD surgery; however, it could result in poor mobility. Thus, whether LSS provides better activities is still unknown., Methods: Among 399 patients who underwent ASD surgery, 62 (≥5 levels fused, >2-year follow-up) underwent fusion from T9-10 to L5 (group L, n=21) or to S2-alar-iliac (group S, n=41). Spinal alignments, Scoliosis Research Society (SRS)-22 scores, performance of activities (clipping toenail, wiping buttock, and wearing socks), proximal and distal junctional failure (PJF+DJF), rod fractures (RFs), and overall revision rates (RRs) were compared between the groups., Results: Group L included younger patients and had longer follow-ups when compared with group S. Although the preoperative pelvic incidence and SRS sagittal modifiers were better in group L, postoperative spinal restorations were nonpathological in both groups. Both groups showed similar deformity progression at the 2-year follow-up; however, group L had lower SRS-22 pain scores. Although "wiping buttocks" did not differ between the groups, the performance of "clipping toenails" and "wearing socks" was poorer in group S at 2 years (possible, group S; 40% vs. group L; 85%-90%). The RRs did not differ between the groups; however, the PJF+DJF rate was higher in group L. DJF was not observed in group S, but occurrence of RFs was noted., Conclusions: Although poorer SRS-22 pain scores might be related to lumbosacral mobility, sufficient restoration, equivalent deformity progression, and similar RRs with better activity imply that lumbosacral preservation should be considered in younger patients with moderate deformities.