141 research outputs found
Error control on mobile station sides in collaborative multiple-input multiple-output systems
Collaboration between mobile stations (MSs) may lead to a new form of wireless communication. Collaboration on MS sides considerably improves signal detection performance, especially for multiple-input multiple-output (MIMO) transmission systems. In this study, a novel detector collaboration system is proposed to reduce the traffic volume on inter-MS collaboration links. Multiple MSs in the immediate vicinity are used to collaboratively decode the MIMO signals received from a base station. Furthermore, we consider a distributed detection system, in which multiple detection MSs decode the MIMO signals independently. Multiple decision results are exploited to improve the error performance. Residual interference coefficients were used to finalize the decision results. The error ratio performance and the traffic volume over collaboration wireless links were compared with those of two combining schemes through computer simulations and field experiments. The results revealed that the proposed error control scheme on mobile station sides offers a better tradeoff between the error performance and the traffic volume on the collaboration wireless links
A Review of Evidence for a Therapeutic Application of Traditional Japanese Kampo Medicine for Oral Diseases/Disorders
Kampo medicines prescribed by specialized medical practitioners and Japanese physicians have gradually reemerged in Japan as alternatives to Western medications. Kampo formulations are composed of several plant extracts and, as such, the broad variety of phytochemicals they contain likely act synergistically to provide their beneficial effects. Kampo medicines have traditionally been prescribed for a number of health conditions, including chronic hepatitis, bronchial asthma, anemia, etc. The aim of this article is to review the beneficial effects of Kampos with respect to oral health. Pertinent papers published between 1970 and 2017 were retrieved by searching in PubMed, ScienceDirect, Web of Science, and Scopus using key words followed by evaluation of the relevant articles. In vitro studies have identified a number of properties that give credence to the potential of Kampos for treating or preventing oral diseases/disorders. Given their anti-microbial and anti-inflammatory properties, they may be promising agents for controlling periodontal diseases, oral mucositis, xerostomia, and drug-induced gingival overgrowth. Since some oral diseases have a complex etiology that involves microbial pathogens and the host immune response, agents with dual functionality such as Kampo phytochemicals may offer a therapeutic advantage
Differentiation of Human Adipose-Derived Mesenchymal Stromal/Stem Cells into Insulin-Producing Cells with A Single Tet-Off Lentiviral Vector System
Objective: Human adipose-derived mesenchymal stromal/stem cells (hASC) constitute an attractive source of stemcells for cell-based therapies in regenerative medicine and tissue engineering as they are easy to acquire fromlipoaspirate, expansion, and genetic modification ex vivo. The combination of Pdx-1, MafA, and NeuroD1 has beenindicated to possess the ability to reprogram various types of cells into insulin-producing cells. The aim of this study is toinvestigate whether MafA and NeuroD1 would cooperate with Pdx-1 in the differentiation of hASC into insulin-producingcells.Materials and Methods:In this experimental study, we generated polycistronic expression vectors expressing Pdx1and MafA/NeuroD1 with a reporter from a human EF-1α promoter using 2A peptides in a single tet-off lentiviral vectorsystem. Briefly, hASC were transduced with the lentiviral vectors and allowed to differentiate into insulin-producing cellsin vitro and in vivo. Thereafter, RNA expression, dithizone staining, and immunofluorescent analysis were conducted.Results: Cleaved transcriptional factors from a single tet-off lentiviral vector were functionally equivalent to their nativeproteins and strictly regulated by doxycycline (Dox). Insulin gene expression in hASC transduced with Pdx1, Pdx1/MafA, and Pdx1/NeuroD1 in differentiation medium were successfully increased by 1.89 ± 0.39, 4.81 ± 0.98, 5.51 ±0.63, respectively, compared to venus-transduced, control hASC. These cells could form dithizone-positive cell clustersin vitro and were found to express insulin in vivo.Conclusion: Using our single tet-off lentiviral vector system, Pdx-1 and MafA/NeuroD1 could be simultaneouslyexpressed in the absence of Dox. Further, this system allowed the differentiation of hASC into insulin-producing cells
Relation of Developmental Disorder Tendency and Internalizing Problems in Higher Grade Elementary School Children
The purpose of this study was to examine whether developmental disorder tendency such as ADHD and ASD tendency are related to internalizing problems through teacher teaching attitudes and school life events, targeting higher grade elementary school children enrolled in regular classes. Higher grade elementary school children (N=206) completed a self-report questionnaire concerning their teacher teaching attitudes, their daily experiences with schoolwork and their relationships with friends and classroom teacher at school, their self-esteem, and internalizing problems. Their homeroom teachers (N=9) rated each children’s developmental disorder tendency. As a result of path analysis, it became clear that developmental disorder tendency to be related to internalizing problems through mediating teacher teaching attitudes, school life events, and self-esteem.井上弥先生・樋口聡先生退職記念特集号本研究は,2018年度に広島大学教育学部に提出した卒業論文を加筆・修正したものです
PUF-Based RFID Authentication Secure and Private under Memory Leakage
RFID tags are getting their presence noticeable and are expected to become an important tool for e-commerce, logistics, point-ofsale transactions, and so on, representing “things” and “human holding things” in transactions. Since a huge amount of tags are expected to be needed to be attached to various “objects,” a low-cost tag manufacturing is necessary. Thus, it is hard to imagine they will implement costly hardware protection mechanisms (like co-processor, TPMs). Therefore, in this context memory leakage (side-channel) attacks become a critical threat. Another well known threat to RFID devices is tag tracing implying violation of privacy.
We consider physically unclonable functions (PUFs) as tamper resilient building blocks cheaper than protected hardware, and propose security against a memory leaking adversary, trying to violate security and privacy of tags (we emphasize that digitally-oriented PUFs are easy to implement and they are more likely than TPMs to be implemented in RFID chips, more so than TPMs). We then design the first provably secure and provably private RFID authentication protocol withstanding information leakage from the entire memory of the tag, and show its two properties: (1) security against man-in-th-middle attack, and (2) privacy protection against tag tracing
Identification of novel canonical strigolactones produced by tomato
Canonical strigolactones (SLs), such as orobanchol, consist of a tricyclic lactone ring (ABC-ring) connected to a methylbutenolide (D-ring). Tomato plants have been reported to produce not only orobanchol but also various canonical SLs related to the orobanchol structure, including orobanchyl acetate, 7-hydroxyorobanchol isomers, 7-oxoorobanchol, and solanacol. In addition to these, structurally unidentified SL-like compounds known as didehydroorobanchol isomers (DDHs), whose molecular mass is 2 Da smaller than that of orobanchol, have been found. Although the SL biosynthetic pathway in tomato is partially characterized, structural elucidation of DDHs is required for a better understanding of the entire biosynthetic pathway. In this study, three novel canonical SLs with the same molecular mass as DDHs were identified in tomato root exudates. The first was 6,7-didehydroorobanchol, while the other two were not in the DDH category. These two SLs were designated phelipanchol and epiphelipanchol because they induced the germination of Phelipanche ramosa, a noxious root parasitic weed of tomato. We also proposed a putative biosynthetic pathway incorporating these novel SLs from orobanchol to solanacol
Photoinduced 1,2-Hydro(cyanomethylation) of Alkenes with a Cyanomethylphosphonium Ylide
An efficient method has been developed for the 1, 2-hydro(cyanomethylation) of alkenes, in which a cyanomethyl radical species is generated from a cyanomethylphosphonium ylide by irradiation with visible light in the presence of an iridium complex, a thiol, and ascorbic acid. The cyanomethyl radical species then adds across the C=C double bond of an alkene to form an elongated alkyl radical species that accepts a hydrogen atom from the thiol to produce an elongated aliphatic nitrile. The ascorbic acid acts as the reductant to complete the catalytic cycle
End-to-end Design of a PUF-based Privacy Preserving Authentication Protocol
We demonstrate a prototype implementation of a provably secure protocol that supports privacy-preserving mutual authentication between a server and a constrained device. Our proposed protocol is based on a physically unclonable function (PUF) and it is optimized for resource-constrained platforms. The reported results include a full protocol analysis, the design of its building blocks, their integration into a constrained device, and finally its performance evaluation. We show how to obtain efficient implementations for each of the building blocks of the protocol, including a fuzzy extractor with a novel helper-data construction technique, a truly random number generator (TRNG), and a pseudo-random function (PRF). The prototype is implemented on a SASEBO-GII board, using the on-board SRAM as the source of entropy for the PUF and the TRNG. We present three different implementations. The first two execute on a MSP430 soft-core processor and have a security level of 64-bit and 128-bit respectively. The third uses a hardware accelerator and has 128-bit security level. To our best knowledge, this work is the first effort to describe the end-to-end design and evaluation of a privacy-preserving PUF-based authentication protocol
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