Dynamic and Decentralized Storage Load Balancing with Analogy to Thermal Diffusion for P2P File Sharing

In this paper we propose a file replication scheme inspired by a thermal diffusion phenomenon for storage load balancing in unstructured peer-to-peer (P2P) file sharing networks. The proposed scheme is designed such that the storage utilization ratios of peers will be uniform, in the same way that the temperature in a field becomes uniform in a thermal diffusion phenomenon. The proposed scheme creates replicas of files in peers probabilistically, where the probability is controlled by using parameters that can be used to find the trade-off between storage load balancing and search performance in unstructured P2P file sharing networks. First, we show through theoretical analysis that the statistical behavior of the storage load balancing controlled by the proposed scheme has an analogy with the thermal diffusion phenomenon. We then show through simulation that the proposed scheme not only has superior performance with respect to balancing the storage load among peers (the primary objective of the present proposal) but also allows the performance trade-off to be widely found. Finally, we qualitatively discuss a guideline for setting the parameter values in order to widely find the performance trade-off from the simulation results

Nonclosure technique with saline-coupled bipolar electrocautery in management of the cut surface after distal pancreatectomy

金沢大学医学部附属病院肝胆膵・移植外科　Background/Purpose: Management of the pancreatic remnant after distal pancreatectomy is still debated, the most serious complication is development of a pancreatic fistula. We developed a nonclosure technique with saline-coupled bipolar electrocautery for preventing fistula formation after distal pancreatectomy as an alternative to traditional stump closure methods. Methods: The distinguishing feature of this technique is nonclosure of the stump, relying instead upon dependable ligation of the main pancreatic duct and sealing of the cut surface by shrinkage accomplished by low-temperature coagulation using saline-coupled bipolar electrocautery. A recent addition has been intraoperative stenting of the remnant pancreatic duct. Results: To date we have used the nonclosure technique in 40 cases, among which 5 (12.5%) developed fistulas: 4 in the nonstenting subgroup (14.8%) and 1 in the stenting subgroup (7.7%). According to a recent classification, 4 fistulas were considered grade A; 1, grade B; and 0, grade C. The grade B patient did not undergo stenting. Conclusion: Our preliminary experience should prompt more widespread evaluation of the nonclosure technique. © Springer Japan 2008

Detection of a new molecular cloud in the LHAASO J2108+5157 region supporting a hadronic PeVatron scenario

PeVatrons are the most powerful naturally occurring particle accelerators in the Universe. The identification of counterparts associated to astrophysical objects such as dying massive stars, molecular gas, star-forming regions, and star clusters is essential to clarify the underlying nature of the PeV emission, i.e., hadronic or leptonic. We present $^{12,13}$CO(J=2$\rightarrow$1) observations made with the 1.85~m radio-telescope of the Osaka Prefecture University toward the Cygnus OB7 molecular cloud, which contains the PeVatron candidate LHAASO J2108+5157. We investigate the nature of the sub-PeV (gamma-ray) emission by studying the nucleon density determined from the content of HI and H$_2$, derived from the CO observations. In addition to MML[2017]4607, detected via the observations of the optically thick $^{12}$CO(J=1$\rightarrow$0) emission, we infer the presence of an optically thin molecular cloud, named [FKT-MC]2022, whose angular size is 1.1$\pm$0.2$^{\circ}$. We propose this cloud as a new candidate to produce the sub-PeV emission observed in LHAASO J2108+5157. Considering a distance of 1.7 kpc, we estimate a nucleon (HI+H$_2$) density of 37$\pm$14 cm$^{-3}$, and a total nucleon mass(HI+H$_2$) of 1.5$\pm$0.6$\times$10$^4$ M$_{\odot}$. On the other hand, we confirm that Kronberger 82 is a molecular clump with an angular size of 0.1$^{\circ}$, a nucleon density $\sim$ 10$^3$ cm$^{-3}$, and a mass $\sim$ 10$^3$ M$_{\odot}$. Although Kronberger 82 hosts the physical conditions to produce the observed emission of LHAASO J2108+5157, [FKT-MC]2022 is located closer to it, suggesting that the latter could be the one associated to the sub-PeV emission. Under this scenario, our results favour a hadronic origin for the emission.Comment: Accepted for publication in PASJ (Publications of the Astronomical Society of Japan). Accepted on 06-Mar-2023. 20 pages, 12 figures, 12 table

Carcinomas of the ventral and dorsal pancreas exhibit different patterns of lymphatic spread

金沢大学医学部附属病院肝胆膵・移植外科　In patients with carcinoma of the head of the pancreas with positive lymph nodes, the extent of an adequate lymph node dissection beyond peripancreatic area has remained controversial. Based on the two anlagens, the ventral or dorsal pancreas, we assessed the lymphatic spread pattern in 58 primary adenocarcinoma of head of the pancreas. Detection of lymph node mestastasis was based on microscopic detection of carcinoma in consecutive serial sections of resected specimens including lymph nodes. When the tumor was confined to the ventral pancreas domain (n=20), the lymph node metastases were limited to areas along the superior mesenteric artery (SMA) besides peripancreatic lymph nodes. When the tumor was in the dorsal pancreas domain (n=6), the lymph node metastases were limited to areas along the common hepatic artery (CHA) and the hepatoduodenal ligament besides peripancreatic lymph nodes. When the tumor was extended into both domains (n=32), the lymph node metastases were distributed widely in areas along the SMA, CHA and the hepatoduodenal ligament besides peripancreatic lymph nodes. Based on these findings, the lymphatic spread of carcinomas of the head of the pancreas can be divided into two patterns by tumor location based on the two anlagens of the pancreas

A pure invasive micropapillary carcinoma of the pancreatic head: Long disease-free survival after pancreatoduodenectomy and adjuvant chemotherapy with gemcitabine [4]

金沢大学医学部附属病院肝胆膵・移植外科