21 research outputs found
Service Compositions in Challenged Mobile Environments Under Spatiotemporal Constraints
Opportunistic network created among mobile devices in challenged environments can be effectively exploited to provide application services. However, data and services may be subject to space and time constraints in challenged environments where it is critical to complete application services within given spatiotemporal limits. This paper discusses an analytical framework that takes into account human mobility traces and provides quantitative measures of the spatiotemporal requirements for service sharing and composition in challenged opportunistic environments. The analytical results provide estimates on feasibility of service sharing and service compositions for various mobility models. To validate the framework, we conduct simulation experiments using multiple human mobility and synthesized datasets. In these experiments, we analyze service composition feasibility, service completion rate and time for resource utilization
Maximizing External Action with Information Provision over Multiple Rounds in Online Social Networks
Online social networks have increased their impact on the real world, which motivates information senders to control the propagation process of information to promote particular actions of online users. However, the existing works on information provisioning seem to oversimplify the users? decision-making process that involves information reception, internal actions of social networks, and external actions of social networks. In particular, characterizing the best practices of information provisioning that promotes the users? external actions is a complex task due to the complexity of the propagation process in OSNs, even when the variation of information is limited. Therefore, we propose a new information diffusion model that distinguishes user behaviors inside and outside of OSNs, and formulate an optimization problem to maximize the number of users who take the external actions by providing information over multiple rounds. Also, we define a robust provisioning policy for the problem, which selects a message sequence to maximize the expected number of desired users under the probabilistic uncertainty of OSN settings. Our experiment results infer that there could exist an information provisioning policy that achieves nearly-optimal solutions in different types of OSNs. Furthermore, we empirically demonstrate that the proposed robust policy can be such a universally optimal solution
DOCK2 is involved in the host genetics and biology of severe COVID-19
「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target
The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force
「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection
Direct measurements of DMS flux from Antarctic fast sea ice to the atmosphere by a chamber technique
We present the first direct measurements of dimethylsulfide (DMS) emissions from Antarctic sea ice to the atmosphere during the seasonal warming period obtained using a chamber technique. Estimated DMS fluxes measured over the snow and superimposed ice (ice formed by the freezing of snow meltwater) were from 0.1 to 0.3 μmol m−2 d−1. The DMS fluxes measured directly over the sea‐ice slush layer after removal of the snow and superimposed ice, ranged from 0.1 to 5.3 μmol m−2 d−1, were large compared to those measured over the snow and superimposed ice. The DMS concentrations in slush water ranged from 1.0 to 103.7 nM. The DMS fluxes increased with increasing DMS concentrations in slush water. Our results indicate that the potential DMS flux measured over the slush layer occurred originally from the slush layer, and was dependent on the DMS concentrations in slush water. However, snow accumulation and the formation of superimposed ice over the slush layer significantly blocks the diffusion of DMS to the atmosphere, with the result that DMS tends to accumulate in the slush layer although the removal process of DMS by photolysis reaction can modify the DMS flux from the slush layer. Hence, the slush layer has the potential to release the DMS to the atmosphere and ocean when the snow and superimposed ice melts
Forensic discrimination of automotive sheet glass manufactured in a same production line by quantitative analysis of iron using an ICP-QMS/QMS with an octapole reaction cell
Effective opportunistic dissemination of spatio-temporal contents in mobile environments
Pasteurella bettyae infection requiring finger amputation due to rapid deterioration and tissue damage
We report a case of infection of the middle finger of a 69-year-old man who visited our hospital. Pus was collected from the erythematous and swollen area of the nail cage of the left-hand middle finger and evaluated in our microbiology laboratory. Gram staining of the specimen revealed multinucleated leukocytes and abundant gram-negative bacilli. Isolated colonies were identified as Pasteurella bettyae using VITEK MS and 16 S ribosomal RNA (rRNA) gene sequencing. The patient's blood test results improved after treatment with penicillin, but the local factors affecting the finger did not improve, and amputation of the middle finger had to be performed. This case represents a report of a very rare hand infection caused by P. bettyae. Polymorphic identification methods, such as MALDI-TOF MS and 16 S rRNA gene sequencing, are needed for members of the genus Pasteurella isolated from severe infections and abnormal sites, and further studies are warranted
Distribution and density of Antarctic krill (Euphausia superba) and ice krill (E. crystallorophias) off Adélie Land in austral summer 2008 estimated by acoustical methods
Impact of the COVID-19 pandemic and multiplex polymerase chain reaction test on outpatient antibiotic prescriptions for pediatric respiratory infection.
This study aimed to evaluate the impact of the prolonged COVID-19 pandemic on outpatient antibiotic prescriptions for pediatric respiratory infections at an acute care hospital in Japan in order to direct future pediatric outpatient antibiotic stewardship. The impact of the COVID-19 pandemic and the FilmArray Respiratory Panel (RP) on outpatient antibiotic prescriptions was assessed from January 2019 to December 2021 using an interrupted time series analysis of children <20 years. The overall antimicrobial prescription rate decreased from 38.7% to 22.4% from the pre-pandemic period to the pandemic. The pandemic (relative risk [RR] level, 0.97 [0.58-1.61]; P = 0.90; RR slope, 1.05 [0.95-1.17] per month; P = 0.310) and FilmArray RP (RR level, 0.90 [0.46-1.75]; P = 0.75; RR slope, 0.95 [0.85-1.06] per month; P = 0.330) had no significant effect on the monthly antibiotic prescription rates. The COVID-19 pandemic was not significantly related to the antibiotic prescription rate, suggesting that it did not impact physicians' behavior toward antibiotic prescriptions. Replacing rapid antigen tests with the FilmArray RP introduced on December 1, 2020, did not affect the magnitude of the reduction in antibiotic prescription rate for pediatric respiratory infections