40 research outputs found
Betraying Revolution: The Foundations of the Japanese Communist Party
With the dissolution of the Soviet Union in 1991 and China’s restoration of capitalism, it is easy to dismiss the relevancy of socialism today. Yet, the Japanese Communist Party (JCP) has enjoyed success at the polls and recognition as a serious opponent of the government of Abe Shinzō. The JCP however is not making a push for power. Instead, it supports liberal opposition parties, most recently throwing its weight behind the new Constitutional Democratic Party of Japan (CDP) in the October 2017 general election. A future CDP government in Japan could include the JCP as a coalition partner. Does this mean the JCP represents a threat to capitalism in Japan and Asia more broadly? The answer is no. This paper examines the foundations of the JCP in the wake of the Russian Revolution in 1917, its evolution along Stalinist lines, and why it supports capitalist parties today. Early Japanese communists had failed to make a proper assessment of the international program initially expounded by the Russian Bolsheviks in 1917. This made it easier for the JCP to fall under nationalist and Stalinist influences in the 1920s. Despite the growing role of the JCP in modern politics, much of the existing research on the party comes from conservative, Cold War-era historians who viewed the JCP through the lens of anti-communism, accepting it as a genuinely revolutionary party. This paper argues rather that the party’s modern, and in fact pro-capitalist, positions can be traced back to this degeneration under Stalinism
Optical Design and Status of the Large Ultra-Violet Optical Infrared Surveyor (LUVOIR)
"In preparation for the Astrophysics 2020 Decadal Survey NASA's Goddard Space Flight Center is studying a segmented aperture telescope with broad astrophysics, solar system, and exoplanet science capability called the Large Ultra-Violet Optical Infrared Surveyor (LUVOIR). This telescope design incorporates many heritage design concepts from the Hubble Space Telescope (HST), James Webb Space Telescope (JWST), and the Wide-field Infrared Survey Telescope (WFIRST). This includes similar ultraviolet instrumentation from HST, deployable segmented optics from JWST, and high-contrast coronagraph technology from WFIRST. Several optical design trades were completed to maximize the science product while maintaining reasonable packaging and fabrication constraints. Other technology developments such as freeform optics, UV enhanced coatings, coronagraph design, and ultra-stable mirrors are being studied to further improve the observatory performance
Acute Sterol O-Acyltransferase 2 (SOAT2) Knockdown Rapidly Mobilizes Hepatic Cholesterol for Fecal Excretion
The primary risk factor for atherosclerotic cardiovascular disease is LDL cholesterol, which can be reduced by increasing cholesterol excretion from the body. Fecal cholesterol excretion can be driven by a hepatobiliary as well as a non-biliary pathway known as transintestinal cholesterol efflux (TICE). We previously showed that chronic knockdown of the hepatic cholesterol esterifying enzyme sterol O-acyltransferase 2 (SOAT2) increased fecal cholesterol loss via TICE. To elucidate the initial events that stimulate TICE, C57Bl/6 mice were fed a high cholesterol diet to induce hepatic cholesterol accumulation and were then treated for 1 or 2 weeks with an antisense oligonucleotide targeting SOAT2. Within 2 weeks of hepatic SOAT2 knockdown (SOAT2HKD), the concentration of cholesteryl ester in the liver was reduced by 70% without a reciprocal increase in hepatic free cholesterol. The rapid mobilization of hepatic cholesterol stores resulted in a ∼ 2-fold increase in fecal neutral sterol loss but no change in biliary cholesterol concentration. Acute SOAT2HKD increased plasma cholesterol carried primarily in lipoproteins enriched in apoB and apoE. Collectively, our data suggest that acutely reducing SOAT2 causes hepatic cholesterol to be swiftly mobilized and packaged onto nascent lipoproteins that feed cholesterol into the TICE pathway for fecal excretion
Reduction of VLDL Secretion Decreases Cholesterol Excretion in Niemann-Pick C1-Like 1 Hepatic Transgenic Mice
An effective way to reduce LDL cholesterol, the primary risk factor of atherosclerotic cardiovascular disease, is to increase cholesterol excretion from the body. Our group and others have recently found that cholesterol excretion can be facilitated by both hepatobiliary and transintestinal pathways. However, the lipoprotein that moves cholesterol through the plasma to the small intestine for transintestinal cholesterol efflux (TICE) is unknown. To test the hypothesis that hepatic very low-density lipoproteins (VLDL) support TICE, antisense oligonucleotides (ASO) were used to knockdown hepatic expression of microsomal triglyceride transfer protein (MTP), which is necessary for VLDL assembly. While maintained on a high cholesterol diet, Niemann-Pick C1-like 1 hepatic transgenic (L1Tg) mice, which predominantly excrete cholesterol via TICE, and wild type (WT) littermates were treated with control ASO or MTP ASO. In both WT and L1Tg mice, MTP ASO decreased VLDL triglyceride (TG) and cholesterol secretion. Regardless of treatment, L1Tg mice had reduced biliary cholesterol compared to WT mice. However, only L1Tg mice treated with MTP ASO had reduced fecal cholesterol excretion. Based upon these findings, we conclude that VLDL or a byproduct such as LDL can move cholesterol from the liver to the small intestine for TICE
Preliminary Jitter Stability Results for the Large UV/Optical/Infrared (LUVOIR) Surveyor Concept Using a Non-Contact Vibration Isolation and Precision Pointing System
The need for high payload dynamic stability and ultra-stable mechanical systems is an overarching technology need for large space telescopes such as the Large Ultraviolet / Optical / Infrared (LUVOIR) Surveyor concept. The LUVOIR concept includes a 15-meter-diameter segmented-aperture telescope with a suite of serviceable instruments operating over a range of wavelengths between 100nm to 2.5 um. Wavefront error (WFE) stability of less than 10 picometers RMS of uncorrected system WFE per wavefront control step represents a drastic performance improvement over current space-based telescopes being fielded. Through the utilization of an isolation architecture that involves no mechanical contact between the telescope and the host spacecraft structure, a system design is realized that maximizes the telescope dynamic stability performance without driving stringent technology requirements on spacecraft structure, sensors or actuators. Through analysis of the LUVOIR finite element model and linear optical model, the wavefront error and Line-Of-Sight (LOS) jitter performance is discussed in this paper when using the Vibration Isolation and Precision Pointing System (VIPPS) being developed cooperatively with Lockheed Martin in addition to a multi-loop control architecture. The multi-loop control architecture consists of the spacecraft Attitude Control System (ACS), VIPPS, and a Fast Steering Mirror on the instrument. While the baseline attitude control device for LUVOIR is a set of Control Moment Gyroscopes (CMGs), Reaction Wheel Assembly (RWA) disturbance contribution to wavefront error stability and LOS stability are presented to give preliminary results in this paper. CMG disturbance will be explored in further work to be completed
Ribosome-Dependent ATPase Interacts with Conserved Membrane Protein in Escherichia coli to Modulate Protein Synthesis and Oxidative Phosphorylation
Elongation factor RbbA is required for ATP-dependent deacyl-tRNA release presumably after each peptide bond formation; however, there is no information about the cellular role. Proteomic analysis in Escherichia coli revealed that RbbA reciprocally co-purified with a conserved inner membrane protein of unknown function, YhjD. Both proteins are also physically associated with the 30S ribosome and with members of the lipopolysaccharide transport machinery. Genome-wide genetic screens of rbbA and yhjD deletion mutants revealed aggravating genetic interactions with mutants deficient in the electron transport chain. Cells lacking both rbbA and yhjD exhibited reduced cell division, respiration and global protein synthesis as well as increased sensitivity to antibiotics targeting the ETC and the accuracy of protein synthesis. Our results suggest that RbbA appears to function together with YhjD as part of a regulatory network that impacts bacterial oxidative phosphorylation and translation efficiency
Evaluating the Effects of SARS-CoV-2 Spike Mutation D614G on Transmissibility and Pathogenicity.
Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant
Evaluating the Effects of SARS-CoV-2 Spike Mutation D614G on Transmissibility and Pathogenicity
Global dispersal and increasing frequency of the SARS-CoV-2 spike protein variant D614G are suggestive of a selective advantage but may also be due to a random founder effect. We investigate the hypothesis for positive selection of spike D614G in the United Kingdom using more than 25,000 whole genome SARS-CoV-2 sequences. Despite the availability of a large dataset, well represented by both spike 614 variants, not all approaches showed a conclusive signal of positive selection. Population genetic analysis indicates that 614G increases in frequency relative to 614D in a manner consistent with a selective advantage. We do not find any indication that patients infected with the spike 614G variant have higher COVID-19 mortality or clinical severity, but 614G is associated with higher viral load and younger age of patients. Significant differences in growth and size of 614G phylogenetic clusters indicate a need for continued study of this variant
Using Plasticizers to Control the Hydrocarbon Selectivity of a Poly(Methyl Methacrylate)-Coated Quartz Crystal Microbalance Sensor
Chemical sensors based on a polymer coated quartz crystal
microbalance
(QCM) generally present poor molecular selectivity for compounds that
contain similar functional groups and possess the same chemical properties.
This paper shows for the first time that the selectivity and sensitivity
of a poly(methyl methacrylate) (PMMA) based QCM sensor can be significantly
enhanced for aromatic hydrocarbons by incorporating a plasticizer
into the polymer film. The sensor was fabricated by spin coating PMMA
onto a quartz crystal, and the influence of plasticizer type and amount
on the response was evaluated. It was shown that the hydrocarbon sensitivity
of plasticizer-free PMMA is negligible, while the sensitivity of plasticized
PMMA was similar to or in some cases greater relative to highly responsive
rubbery polymers such as polyisobutylene (PIB). Detection limits of
4.0, 1.5, 0.4, 0.6, and 0.1 ppm were obtained on a PMMA film containing
25% w/w di(2-ethylhexyl) phthalate for benzene, toluene, ethylbenzene, <i>p</i>-xylene, and naphthalene, respectively. We found that at
low plasticizer levels (∼10% w/w) the PMMA film was more sensitive
toward ethylbenzene and <i>p</i>-xylene over naphthalene
when compared to a PIB film under similar measurement conditions.
Attenuated total reflectance Fourier transform infrared spectroscopy
(ATR-FTIR) measurements were performed to understand the sensing mechanism,
and these studies confirmed a higher hydrocarbon uptake by PMMA in
the presence of plasticizer. Positron annihilation lifetime spectroscopy
(PALS) studies detected variations in the free volume properties of
the polymer films as a function of plasticizer content. The accessible
free volume as measured by PALS was significantly less in the PMMA
films compared to the PIB, and this result correlates favorably with
differences in the QCM response pattern. The QCM results have been
rationalized in terms of free volume theory which is responsible for
the higher hydrocarbon diffusion/sorption with increased plasticizer
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