563 research outputs found
Structural Development Studies of Subtype-Selective Ligands for Peroxisome Proliferator-Activated Receptors (PPARs) Based on the 3,4-Disubstituted Phenylpropanoic Acid Scaffold as a Versatile Template
Improvements in our understanding of the functions of the nuclear receptor peroxisome proliferator-activated receptor (PPAR) subtypes as pleiotropic regulators of biological responses, including lipid, lipoprotein, glucose homeostasis, inflammation, differentiation and proliferation of various cancer cells, and memory, have provided an opportunity to develop novel PPAR ligands with characteristic subtype selectivity. Such ligands are not only chemical tools to investigate the functions of PPARs, but also candidates for the treatment of PPAR-mediated diseases, including metabolic syndrome, inflammation, dementia, and cancer. This minireview summarizes our work on the design, synthesis, and pharmacological evaluation of subtype-selective PPAR agonists based on the use of 3,4-disubstituted phenylpropanoic acid as a versatile template
Additional kernel observer: privilege escalation attack prevention mechanism focusing on system call privilege changes
Cyberattacks, especially attacks that exploit operating system vulnerabilities, have been increasing in recent years. In particular, if administrator privileges are acquired by an attacker through a privilege escalation attack, the attacker can operate the entire system and cause serious damage. In this paper, we propose an additional kernel observer (AKO) that prevents privilege escalation attacks that exploit operating system vulnerabilities. We focus on the fact that a process privilege can be changed only by specific system calls. AKO monitors privilege information changes during system call processing. If AKO detects a privilege change after system call processing, whereby the invoked system call does not originally change the process privilege, AKO regards the change as a privilege escalation attack and applies countermeasures against it. AKO can therefore prevent privilege escalation attacks. Introducing the proposed method in advance can prevent this type of attack by changing any process privilege that was not originally changed in a system call, regardless of the vulnerability type. In this paper, we describe the design and implementation of AKO for Linux x86 64-bit. Moreover, we show that AKO can be expanded to prevent the falsification of various data in the kernel space. Then, we present an expansion example that prevents the invalidation of Security-Enhanced Linux. Finally, our evaluation results show that AKO is effective against privilege escalation attacks, while maintaining low overhead
The Stellar Mass, Star Formation Rate and Dark Matter Halo Properties of LAEs at
We present average stellar population properties and dark matter halo masses
of \lya emitters (LAEs) from SED fitting and clustering analysis,
respectively, using objects () in four separate
fields of deg in total. With an average stellar mass of and star formation rate of , the LAEs lie on an extrapolation
of the star-formation main sequence (MS) to low stellar mass. Their effective
dark matter halo mass is estimated to be $4.0_{-2.9}^{+5.1} \times 10^{10}\
{\mathrm M_\odot}1.22^{+0.16}_{-0.18}z \sim 21.8\, \pm\, 0.396\%.
However, the difference in the bias values can be explained if cosmic variance
is taken into account. If such a low halo mass implies a low HI gas mass, this
result appears to be consistent with the observations of a high \lya escape
fraction. With the low halo masses and ongoing star formation, our LAEs have a
relatively high stellar-to-halo mass ratio (SHMR) and a high efficiency of
converting baryons into stars. The extended Press-Schechter formalism predicts
that at z=0z \sim 2$ as some previous
studies have reported for the LMC itself.Comment: 34 pages, 15 figures, 6 tables. Accepted for publication in PAS
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