Wetting-driven formation of present-day loess structure

© 2020 The Authors Present-day loess, especially Malan loess formed in Later Quaternary, has a characteristic structure composed of vertically aligned strong units and weak segments. Hypotheses describing how this structure forms inside original loess deposits commonly relate it to wetting-drying process. We tested this causal relationship by conducting unique experiments on synthetic samples of initial loess deposits fabricated by free-fall of loess particles. These samples were subjected to a wetting-drying cycle, and their structural evolutions were documented by close-up photography and CT scanning. Analysis of these records revealed three key stages of structural evolution: initiation (evenly distributed cracks appear due to wetting); inhomogeneitization (some cracks grow, forming large polygons); and development (polygon-forming cracks grow further - cracks within polygons narrow down or heal up). These experiments successfully reproduced the characteristic structure of present-day loess, and led to a discovery that it is the wetting of initial loess that initiates and drives the structural evolution, while drying preserves and expands resulting features

Vibration Measurements to Study the Effect of Cryogen Flow in Superconducting Quadrupole.

The conceptual design of compact superconducting magnets for the International Linear Collider final focus is presently under development. A primary concern in using superconducting quadrupoles is the potential for inducing additional vibrations from cryogenic operation. We have employed a Laser Doppler Vibrometer system to measure the vibrations in a spare RHIC quadrupole magnet under cryogenic conditions. Some preliminary results of these studies were limited in resolution due to a rather large motion of the laser head as well as the magnet. As a first step towards improving the measurement quality, a new set up was used that reduces the motion of the laser holder. The improved setup is described, and vibration spectra measured at cryogenic temperatures, both with and without helium flow, are presented

Spectroscopic studies of Dy-168,170 using CLARA and PRISMA

Preliminary results from an experiment aiming at Dy-170. Submitted to the LNL Annual Report 2008.Comment: 2 pages, 4 figures, Submitted to the LNL Annual Report 200

Urban land planning: The role of a Master Plan in influencing local temperatures

Land use planning (LUP) is central for managing issues related to climatic variation in urban environments. However, Master Plans (MPs) usually do not include climatic aspects, and few studies have addressed climate change at the urban scale, especially in developing countries. This paper proposes a framework with ten categories for assessment of climatic variation in urban LUP. Each category comprises attributes that describe a complex of relationships in influencing local temperature variations. They are analyzed for the case of the Master Plan of Porto Alegre (MPPA), the Southernmost metropolis of Brazil. It is concluded that the MPPA is strongly grounded in climate-related land and zoning coordination, but exhibits weaknesses in building, cartographical and social aspects considered synergistically relevant for tackling problems related to urban climate variation. Furthermore, the MPPA does not contain provisions related to monitoring of local climate and greenhouse gases (GHG) emissions and it is ineffective for improving energy efficiency. Specific MPPA failures stemming from these weaknesses include: an increase of 21.79% in the city's urbanized area from 1986 to 2011 to accommodate a similar increase in population, with significant horizontal sprawl; average temperature rise of 0.392. °C from 1991-2000 to 2001-2010, with statistically significant increases in temperature found since 1931; significant vehicle traffic increases, especially since 2007. From these findings, it is possible to conclude that the MPPA does not offer answers to all the imbalances related to land use, and therefore gives insufficient support to tackle the issue of rising temperatures

Polycrystalline {\gamma}-boron: As hard as polycrystalline cubic boron nitride

The Vickers hardness of polycrystalline {\gamma}-B was measured using a diamond indentation method. The elastic properties of polycrystalline {\gamma}-B (B=213.9 GPa, G=227.2 GPa, and E=503.3 GPa) were determined using ultrasonic measurement at ambient condition. Under the loading force up to 20 N, our test gave an average Vickers hardness in the asymptotic-hardness region of 30.3 GPa. The average fracture toughness was measured as 4.1MPa m1/2. Additionally, We also measured the hardness and elastic properties of polycrystalline {\beta}-B and PcBN for comparison. The hardness and elastic properties for polycrystalline {\gamma}-B was found to be very close to that of PcBN. Our results suggest that the polycrystalline {\gamma}-B could be a superhard polycrystalline material for industrial applications.Comment: 16 page

A G protein-coupled, IP3/protein kinase C pathway controlling the synthesis of phosphaturic hormone FGF23

Dysregulated actions of bone-derived phosphaturic hormone fibroblast growth factor 23 (FGF23) result in several inherited diseases, such as X-linked hypophosphatemia (XLH), and contribute substantially to the mortality in kidney failure. Mechanisms governing FGF23 production are poorly defined. We herein found that ablation of the Gq/11α–like, extralarge Gα subunit (XLαs), a product of GNAS, exhibits FGF23 deficiency and hyperphosphatemia in early postnatal mice (XLKO). FGF23 elevation in response to parathyroid hormone, a stimulator of FGF23 production via cAMP, was intact in XLKO mice, while skeletal levels of protein kinase C isoforms α and δ (PKCα and PKCδ) were diminished. XLαs ablation in osteocyte-like Ocy454 cells suppressed the levels of FGF23 mRNA, inositol 1,4,5-trisphosphate (IP3), and PKCα/PKCδ proteins. PKC activation in vivo via injecting phorbol myristate acetate (PMA) or by constitutively active Gqα-Q209L in osteocytes and osteoblasts promoted FGF23 production. Molecular studies showed that the PKC activation–induced FGF23 elevation was dependent on MAPK signaling. The baseline PKC activity was elevated in bones of Hyp mice, a model of XLH. XLαs ablation significantly, but modestly, reduced serum FGF23 and elevated serum phosphate in Hyp mice. These findings reveal a potentially hitherto-unknown mechanism of FGF23 synthesis involving a G protein–coupled IP3/PKC pathway, which may be targeted to fine-tune FGF23 levels

Adult kidney stem/progenitor cells contribute to regeneration through the secretion of trophic factors

Adult kidney stem cells are known to have important roles in renal regeneration after acute kidney injury. Although trophic factors from tissue stem cells have been reported to promote the regeneration of other organs, there is limited number of evidence of this phenomenon in the kidneys. Here, we explored the effects of secreted factors from kidney stem cells. We intraperitoneally administered culture supernatant obtained from adult rat kidney stem/progenitor cells into rat kidney ischemia/reperfusion injury models, and the treatment significantly ameliorated renal tubulointerstitial injury, suppressed tubular cell apoptosis, diminished inflammation and promoted the proliferation of both residual renal cells and immature cells. In vitro, treatment with culture supernatant from kidney stem cells significantly promoted cell proliferation and suppressed cisplatin-induced cell apoptosis in both normal rat kidney cells and kidney stem cells. In addition, treatment with culture supernatant increased the expression of nestin in normal rat kidney cells, suggesting the dedifferentiation of tubular cells into stem-like cells. Analysis of the culture supernatant revealed that it contained a variety of growth factors. Taken together, the results suggest that these factors together lead to renal regeneration. In conclusion, adult kidney stem cells contribute to renal regeneration indirectly through the secretion of regenerative factors

Chitosan-zein nano-in-microparticles Capable of Mediating in vivo Transgene Expression Following Oral Delivery

The oral route is an attractive delivery route for the administration of DNA-based therapeutics, specifically for applications in gene therapy and DNA vaccination. However, oral DNA delivery is complicated by the harsh and variable conditions encountered throughout gastrointestinal (GI) transit, leading to degradation of the delivery vector and DNA cargo, and subsequent inefficient delivery to target cells. In this work, we demonstrate the development and optimization of a hybrid-dual particulate delivery system consisting of two natural biomaterials, zein (ZN) and chitosan (CS), to mediate oral DNA delivery. Chitosan-Zein Nano-in-Microparticles (CS-ZN-NIMs), consisting of core Chitosan/DNA nanoparticles (CS/DNA NPs) prepared by ionic gelation with sodium tripolyphosphate (TPP), further encapsulated in ZN microparticles, were formulated using a water-in-oil emulsion (W/O). The resulting particles exhibited high CS/DNA NP loading and encapsulation within ZN microparticles. DNA release profiles in simulated gastric fluid (SGF) were improved compared to un-encapsulated CS/ DNA NPs. Further, site-specific degradation of the outer ZN matrix and release of transfection competent CS/ DNA NPs occurred in simulated intestinal conditions with CS/DNA NP cores successfully mediating transfection in vitro. Finally, CS-ZN-NIMs encoding GFP delivered by oral gavage in vivo induced the production of anti-GFP IgA antibodies, demonstrating in vivo transfection and expression. Together, these results demonstrate the successful formulation of CS-ZN-NIMs and their potential to improve oral gene delivery through improved protection and controlled release of DNA cargo