Dark Energy Density and IS (Israel-Stewart) Bulk Viscosity Model

We investigate the thermodynamics of a dark energy bulk viscosity model as a cosmic fluid. In this regard, the two theories of Eckart and Israel-Stewart (IS) are the basis of our work. Therefore, we first investigate the thermodynamics of cosmic fluids in the dark energy bulk viscosity model and the general relationships. Then, we express the thermodynamic relationships of Eckart's theory. Due to the basic equations of Eckart's theory and Friedmann's equations, we consider two states, one is $p=-\rho$ (standard) and the other is $p\neq-\rho$ (non-standard). In the standard state, we define the pressure $(p)$, energy density $(\rho)$, and bulk viscosity coefficient $(\xi)$ of the cosmic fluid in terms of cosmic time and we obtain its relations. We also mention that in this standard state, because of $p=-\rho$, the value of $a(t)$ is zero, so $a(t)$ is not defined in this state. But in the non-standard case $(p\neq-\rho)$ the bulk viscosity coefficient $(\xi)$ is zero and only the scale factor and pressure and energy density of the cosmic fluid is defined. We also consider two states of constant and variable bulk viscosity coefficients and obtain three Hubble constant parameters and scale factors in terms of cosmic time, and energy density in terms of the scale factor. In the state of variable bulk viscosity coefficient, we consider the viscosity coefficient as the power-law from energy density $(\xi=\alpha\rho^{s})$, which is $\alpha>0$ and a constant. Following, we discuss the dissipative effects of cosmic fluids and examine the effects of energy density for dark energy in the Israel-Stewart(IS) theory. The results are comprehensively presented in two tables (1) and (2).Comment: 28 pages, 11 figurs, 2 table

Development of an Integrated System for Ozone Treated Harvested Rainwater in Perspective of Green Building Scenario of Malaysia

In this study an integrated system for rainwater harvesting and ozone treatment has been developed for continuous supply of drinkable water. In the perspective of Malaysian scenario ozone treatment of rainwater is still considered a new approach. This pilot project is launched to justify the reliability, the effectiveness and the economic aspect of ozone treated rainwater. The samples of rainwater were analyzed for both physiochemical and microbiological parameters before and after the ozone treatment. The injection of ozone has shown prominent improvement in both parameters and also the quality up gradation of the original rainwater. The results are encouraging and suggest that the technique is promising to fulfil both requirements continuous supply of rainwater as well as accomplish successful ozone treatment. The system can readily be installed at any location and measurements assure that it could certainly provide an alternative water source when conventional piped supply is unavailable. In the perspective of Green Building scenario this integrated approach of ozone treated harvested rainwater might be able to reduce the impact of environmental factors. Keywords: Ozone treatment, Rainwater quality improvement, Water quality, Disinfection with ozone, Green building concept

COVID-19 in rheumatoid arthritis cases: an Iranian referral center experience

Coronavirus infections, known as COVID-19, can induce a fatal respiratory system infection and also affect other organs, such as the kidney and heart. The mortality rate has been estimated between 1 and 5 in previous reports; however, the mortality and morbidity can be higher in patients with the immune-deficiency condition. Rheumatoid arthritis (RA) is one of the most rheumatoid disorders, and it is important to report their clinical and paraclinical data when affected with COVID-19. Evidence about their laboratory and radiologic findings is limited. In this case series, 10 cases of chronic and approved rheumatoid arthritis (RA) affected by COVID-19 are presented. Only 40 had dry cough, but myalgia and weakness as the general first presentation of infections was reported in most cases (80). Gastrointestinal symptoms, including nausea/vomiting, diarrhea, anorexia, and abdominal pain, were reported in 50 of individuals. In blood cell count, 30 of cases had thrombocytopenia, and ESR in all cases was positive. Abnormal CRP and elevated LDH were seen in 90 of cases. In HRCT assessment, all cases had an abnormal parenchymal pattern, and 90 of cases presented the usual pattern of COVID-19 (bilateral multifocal GGO/consolidation). Although it is a limited report, these findings are helpful for comparison of clinical and paraclinical cases in RA cases with normal cases. © 2020, International League of Associations for Rheumatology (ILAR)

An Experimental Study on the Ordered Alloy Ni_2Cr

The ordered alloy Ni_2Cr has been investigated by means of electron diffraction, electron microscopy, calorimetry, resistometry and tensile tests. The formation of the Pt_2Mo type superstructure is revealed by an electron diffraction study on the single crystalline specimens. The size of ordered domains is of the order of magnitude of several hundred A even in the well annealed state. The so-called \u27K-state\u27 which is characterized by the initial increase in electrical resistivity upon isothermal annealing is attributed to the existence of very fine ordered domains. Superdislocations consisting of triple dislocations are sometimes observed in various stages of ordering, and the mechanical properties are briefly discussed in the light of electron microscopic observation. The energy and entropy of transformation are evaluated as about 1.0 kcal/g・atom and 1.2 cal/g・atom-deg on the alloy of 32.1 at% Cr annealed at 500℃ for about 3000 hr

A role for core planar polarity proteins in cell contact-mediated orientation of planar cell division across the mammalian embryonic skin

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. © The Author(s) 2017. Supplementary information accompanies this paper at doi:10.1038/s41598-017-01971-2.The question of how cell division orientation is determined is fundamentally important for understanding tissue and organ shape in both healthy or disease conditions. Here we provide evidence for cell contact-dependent orientation of planar cell division in the mammalian embryonic skin. We propose a model where the core planar polarity proteins Celsr1 and Frizzled-6 (Fz6) communicate the long axis orientation of interphase basal cells to neighbouring basal mitoses so that they align their horizontal division plane along the same axis. The underlying mechanism requires a direct, cell surface, planar polarised cue, which we posit depends upon variant post-translational forms of Celsr1 protein coupled to Fz6. Our hypothesis has parallels with contact-mediated division orientation in early C. elegans embryos suggesting functional conservation between the adhesion-GPCRs Celsr1 and Latrophilin-1. We propose that linking planar cell division plane with interphase neighbour long axis geometry reinforces axial bias in skin spreading around the mouse embryo body.Peer reviewe

Order and Stochastic Dynamics in Drosophila Planar Cell Polarity

Cells in the wing blade of Drosophila melanogaster exhibit an in-plane polarization causing distal orientation of hairs. Establishment of the Planar Cell Polarity (PCP) involves intercellular interactions as well as a global orienting signal. Many of the genetic and molecular components underlying this process have been experimentally identified and a recently advanced system-level model has suggested that the observed mutant phenotypes can be understood in terms of intercellular interactions involving asymmetric localization of membrane bound proteins. Among key open questions in understanding the emergence of ordered polarization is the effect of stochasticity and the role of the global orienting signal. These issues relate closely to our understanding of ferromagnetism in physical systems. Here we pursue this analogy to understand the emergence of PCP order. To this end we develop a semi-phenomenological representation of the underlying molecular processes and define a “phase diagram” of the model which provides a global view of the dependence of the phenotype on parameters. We show that the dynamics of PCP has two regimes: rapid growth in the amplitude of local polarization followed by a slower process of alignment which progresses from small to large scales. We discuss the response of the tissue to various types of orienting signals and show that global PCP order can be achieved with a weak orienting signal provided that it acts during the early phase of the process. Finally we define and discuss some of the experimental predictions of the model

Primary Cilia Are Not Required for Normal Canonical Wnt Signaling in the Mouse Embryo

Sonic hedgehog (Shh) signaling in the mouse requires the microtubule-based organelle, the primary cilium. The primary cilium is assembled and maintained through the process of intraflagellar transport (IFT) and the response to Shh is blocked in mouse mutants that lack proteins required for IFT. Although the phenotypes of mouse IFT mutants do not overlap with phenotypes of known Wnt pathway mutants, recent studies report data suggesting that the primary cilium modulates responses to Wnt signals.We therefore carried out a systematic analysis of canonical Wnt signaling in mutant embryos and cells that lack primary cilia because of loss of the anterograde IFT kinesin-II motor (Kif3a) or IFT complex B proteins (Ift172 or Ift88). We also analyzed mutant embryos with abnormal primary cilia due to defects in retrograde IFT (Dync2h1). The mouse IFT mutants express the canonical Wnt target Axin2 and activate a transgenic canonical Wnt reporter, BAT-gal, in the normal spatial pattern and to the same quantitative level as wild type littermates. Similarly, mouse embryonic fibroblasts (MEFs) derived from IFT mutants respond normally to added Wnt3a. The switch from canonical to non-canonical Wnt also appears normal in IFT mutant MEFs, as both wild-type and mutant cells do not activate the canonical Wnt reporter in the presence of both Wnt3a and Wnt5a.We conclude that loss of primary cilia or defects in retrograde IFT do not affect the response of the midgestation embryo or embryo-derived fibroblasts to Wnt ligands

Wdpcp, a PCP Protein Required for Ciliogenesis, Regulates Directional Cell Migration and Cell Polarity by Direct Modulation of the Actin Cytoskeleton

Planar cell polarity (PCP) regulates cell alignment required for collective cell movement during embryonic development. This requires PCP/PCP effector proteins, some of which also play essential roles in ciliogenesis, highlighting the long-standing question of the role of the cilium in PCP. Wdpcp, a PCP effector, was recently shown to regulate both ciliogenesis and collective cell movement, but the underlying mechanism is unknown. Here we show Wdpcp can regulate PCP by direct modulation of the actin cytoskeleton. These studies were made possible by recovery of a Wdpcp mutant mouse model. Wdpcp-deficient mice exhibit phenotypes reminiscent of Bardet-Biedl/Meckel-Gruber ciliopathy syndromes, including cardiac outflow tract and cochlea defects associated with PCP perturbation. We observed Wdpcp is localized to the transition zone, and in Wdpcp-deficient cells, Sept2, Nphp1, and Mks1 were lost from the transition zone, indicating Wdpcp is required for recruitment of proteins essential for ciliogenesis. Wdpcp is also found in the cytoplasm, where it is localized in the actin cytoskeleton and in focal adhesions. Wdpcp interacts with Sept2 and is colocalized with Sept2 in actin filaments, but in Wdpcp-deficient cells, Sept2 was lost from the actin cytoskeleton, suggesting Wdpcp is required for Sept2 recruitment to actin filaments. Significantly, organization of the actin filaments and focal contacts were markedly changed in Wdpcp-deficient cells. This was associated with decreased membrane ruffling, failure to establish cell polarity, and loss of directional cell migration. These results suggest the PCP defects in Wdpcp mutants are not caused by loss of cilia, but by direct disruption of the actin cytoskeleton. Consistent with this, Wdpcp mutant cochlea has normal kinocilia and yet exhibits PCP defects. Together, these findings provide the first evidence, to our knowledge, that a PCP component required for ciliogenesis can directly modulate the actin cytoskeleton to regulate cell polarity and directional cell migration

Zyxin Links Fat Signaling to the Hippo Pathway

Using genetic and molecular analyses, the authors identify Zyx as a positive regulator of Hippo signaling and characterize its role within the pathway