217 research outputs found
Consultant Report Securing Australia’s Future STEM : Country Comparisons
STEM Country Comparisons: JapanSecuring Australia’s Future Project 2. Australian Council of Learned Academies (ACOLA)This report can be found at www.acola.org.a
Evaluation and design of function for tracing diffusion of classified information for file operations with KVM
Cases of classified information leakage have become increasingly common. To address this problem, we have developed a function for tracing the diffusion of classified information within an operating system. However, this function suffers from the following two problems: first, in order to introduce the function, the operating system's source code must be modified. Second, there is a risk that the function will be disabled when the operating system is attacked. Thus, we have designed a function for tracing the diffusion of classified information in a guest operating system by using a virtual machine monitor. By using a virtual machine monitor, we can introduce the proposed function in various environments without modifying the operating system's source code. In addition, attacks aimed at the proposed function are made more difficult, because the virtual machine monitor is isolated from the operating system. In this paper, we describe the implementation of the proposed function for file operations and child process creation in the guest operating system with a kernel-based virtual machine. Further, we demonstrate the traceability of diffusing classified information by file operations and child process creation. We also report the logical lines of code required to introduce the proposed function and performance overheads
Depth profiles of electron and hole traps generated by reactive ion etching near the surface of 4H-SiC
Deep levels in the whole bandgap of 4H-SiC generated by reactive ion etching (RIE) are investigated with both n- and p-type SiC Schottky barrier diodes by deep-level transient spectroscopy (DLTS). Depth profiles of the observed deep levels were analyzed using the DLTS peak intensities at various bias voltages and numerical calculations. The major electron traps detected after RIE and subsequent annealing at 1300℃ include the Z₁⁄₂ (Ec-0.66eV), ON1 (Ec-0.88eV), ON2 (Ec-0.95eV), and EH₆⁄₇ (Ec-1.50eV) centers, and the major hole traps include the UK1 (Ev+0.51eV), UK2 (Ev+0.72eV), HK0 (Ev+0.77eV), HK2 (Ev+0.79eV), and HK3 (Ev+1.31eV) centers, where Ec and Ev denote the conduction and valence band edges, respectively. Most of the traps were localized near the surface (2 μm). By annealing at 1400℃, most of the hole traps were eliminated, but several electron traps remained. From these results, the origins of these defects are discussed
Impact of Novel Incorporation of CT-based Segment Mapping into a Conjugated Gradient Algorithm on Bone SPECT Imaging: Fundamental Characteristics of a Context-specific Reconstruction Method
Objective(s): The latest single-photon emission computed tomography (SPECT)/computed tomography (CT) reconstruction system, referred to as xSPECT Bone™, is a context-specific reconstruction system utilizing tissue segmentation information from CT data, which is called a zone map. The aim of this study was to evaluate theeffects of zone-map enhancement incorporated into the ordered-subset conjugated gradient minimization (OSCGM) reconstruction method on SPECT images.Methods: Image quality with zone-map enhanced OSCGM (OSCGMz) and nonenhanced OSCGM methods was compared using various reconstruction parameters. The compartment phantom had 3 radioactive sections with CT values of about 1000, 250, and 0 HU. SPECT data were acquired using a lowenergy high-resolution (LEHR) collimator, with a 256×256 matrix and 2.4-mm pixel size. The performances of the 2 reconstruction methods (OSCGM vs.OSCGMz) were evaluated on the basis of %error, coefficient of variation (%CV), and normalized mean squared error (NMSE), and adequate iterative update numbers were determined. The relative CV representing the ratio of smoothed images to non-smoothed images was calculated to evaluate the effects of the Gaussian filter on each section set with different CT values.Results: On comparing the OSCGM and OSCGMz methods, it was found that the %error of the OSCGMz method tended to show convergence with fewer updates, especially in the high CT value section mimicking bone absorption. In the watersection, the %CV of the OSCGMz method was lower than that of the OSCGM method. The NMSE minimum values for the OSCGM and OSCGMz methods were obtained at 30 and 20 updates, respectively. The relative CV for the OSCGMzmethod in the water section decreased remarkably according to the size of the full width at half maximum (FWHM) of the Gaussian filter.Conclusion: The zone-map enhancement contributed to SPECT reconstruction for the reproduction of radioactive concentrations in bone tissues, using a low number of OSCGM updates. Our findings indicated that the incorporation of zone maps into SPECT reconstruction might improve image quality
Organellar Glue: A Molecular Tool to Artificially Control Chloroplast–Chloroplast Interactions
細胞小器官を接着する新技術「オルガネラグルー」を開発 --オルガネラ間コミュニケーションの操作に期待--. 京都大学プレスリリース. 2022-09-30.Organelles can physically interact to facilitate various cellular processes such as metabolite exchange. Artificially regulating these interactions represents a promising approach for synthetic biology. Here, we artificially controlled chloroplast–chloroplast interactions in living plant cells with our organelle glue (ORGL) technique, which is based on reconstitution of a split fluorescent protein. We simultaneously targeted N-terminal and C-terminal fragments of a fluorescent protein to the chloroplast outer envelope membrane or cytosol, respectively, which induced chloroplast–chloroplast interactions. The cytosolic C-terminal fragment likely functions as a bridge between two N-terminal fragments, thereby bringing the chloroplasts in close proximity to interact. We modulated the frequency of chloroplast–chloroplast interactions by altering the ratio of N- and C-terminal fragments. We conclude that the ORGL technique can successfully control chloroplast–chloroplast interactions in plants, providing a proof of concept for the artificial regulation of organelle interactions in living cells
Stargazer: Long-Term and Multiregional Measurement of Timing/ Geolocation-Based Cloaking
Malicious hosts have come to play a significant and varied role in today's cyber attacks. Some of these hosts are equipped with a technique called cloaking, which discriminates between access from potential victims and others and then returns malicious content only to potential victims. This is a serious threat because it can evade detection by security vendors and researchers and cause serious damage. As such, cloaking is being extensively investigated, especially for phishing sites. We are currently engaged in a long-term cloaking study of a broader range of threats. In the present study, we implemented Stargazer, which actively monitors malicious hosts and detects geographic and temporal cloaking, and collected 30,359,410 observations between November 2019 and February 2022 for 18,397 targets from 13 sites where our sensors are installed. Our analysis confirmed that cloaking techniques are widely abused, i.e., not only in the context of specific threats such as phishing. This includes geographic and time-based cloaking, which is difficult to detect with single-site or one-shot observations. Furthermore, we found that malicious hosts that perform cloaking include those that survive for relatively long periods of time, and those whose contents are not present in VirusTotal. This suggests that it is not easy to observe and analyze the cloaking malicious hosts with existing technologies. The results of this study have deepened our understanding of various types of cloaking, including geographic and temporal ones, and will help in the development of future cloaking detection methods
Pain following COVID-19 vaccination
Pain at the injection site is the most frequent reaction among COVID-19 vaccine recipients, but its characteristics were not fully described yet. The purpose of this study was to investigate multiple domains of pain following BNT162b2 mRNA vaccination. We included 107 subjects undergoing primary shot of the vaccination twice into deltoid muscle with a 3-week interval. They completed 6 sessions of pain assessments, one before the first and second dose (1-0, 2-0), and 1st / 7th day after the first and second dose (1-1 / 1-7, 2-1 / 2-7). Pain visual analog scale (VAS), pain distribution, and pressure pain threshold (PPT) on deltoid muscle were evaluated in each session. The mean VAS (at rest / shoulder motion) was 6.0 / 27.6 mm at 1-1, and 12.8 / 34.0 mm at 2-1. Approximately, 90% of recipients showed localized pain within the upper arm. Percentage change of PPTs at 1-1 and 2-1 was bilaterally (ipsilateral / contralateral) decreased to 87.4 / 89.4% and 80.6 / 91.0%, which was recovered to the baseline level at 1-7 and 2-7. Temporary, mild-to-moderate intensity, localized distribution, concomitant with bilateral mechanical hyperalgesia on the deltoid muscle, were typical pain characteristics following this vaccination. These findings provide a rationale that will be informative for future recipients
中鎖脂肪酸と糖質の併用摂取は癌関連骨格筋萎縮から保護する
Skeletal muscle volume is associated with prognosis of cancer patients. Maintenance of skeletal muscle is an essential concern in cancer treatment. In nutritional intervention, it is important to focus on differences in metabolism between tumor and skeletal muscle. We examined the influence of oral intake of glucose (0%, 10%, 50%) and 2% medium-chain fatty acid (lauric acid, LAA, C12:0) on tumor growth and skeletal muscle atrophy in mouse peritoneal metastasis models using CT26 mouse colon cancer cells and HT29 human colon cancer cells. After 2 weeks of experimental breeding, skeletal muscle and tumor were removed and analyzed. Glucose intake contributed to prevention of skeletal muscle atrophy in a sugar concentration-dependent way and also promoted tumor growth. LAA ingestion elevated the level of skeletal muscle protein and suppressed tumor growth by inducing tumor-selective oxidative stress production. When a combination of glucose and LAA was ingested, skeletal muscle mass increased and tumor growth was suppressed. Our results confirmed that although glucose is an important nutrient for the prevention of skeletal muscle atrophy, it may also foster tumor growth. However, the ingestion of LAA inhibited tumor growth, and its combination with glucose promoted skeletal muscle integrity and function, without stimulating tumor growth. These findings suggest novel strategies for the prevention of skeletal muscle atrophy.博士(医学)・甲第733号・令和2年3月16日© 2019 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.
This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License(https://creativecommons.org/licenses/by-nc/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes
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