CART: an Hrs/actinin-4/BERP/myosin V protein complex required for efficient receptor recycling.

Altering the number of surface receptors can rapidly modulate cellular responses to extracellular signals. Some receptors, like the transferrin receptor (TfR), are constitutively internalized and recycled to the plasma membrane. Other receptors, like the epidermal growth factor receptor (EGFR), are internalized after ligand binding and then ultimately degraded in the lysosome. Routing internalized receptors to different destinations suggests that distinct molecular mechanisms may direct their movement. Here, we report that the endosome-associated protein hrs is a subunit of a protein complex containing actinin-4, BERP, and myosin V that is necessary for efficient TfR recycling but not for EGFR degradation. The hrs/actinin-4/BERP/myosin V (CART [cytoskeleton-associated recycling or transport]) complex assembles in a linear manner and interrupting binding of any member to its neighbor produces an inhibition of transferrin recycling rate. Disrupting the CART complex results in shunting receptors to a slower recycling pathway that involves the recycling endosome. The novel CART complex may provide a molecular mechanism for the actin-dependence of rapid recycling of constitutively recycled plasma membrane receptors.

Seasonal Deuterium Excess in a Tien Shan Ice Core: Influence of Moisture Transport and Recycling in Central Asia

Stable water isotope (delta(18)O, deltaD) data from a high elevation (5100 masl) ice core recovered from the Tien Shan Mountains, Kyrgyzstan, display a seasonal cycle in deuterium excess (d = deltaD - 8* delta(18)O) related to changes in the regional hydrologic cycle during 1994 - 2000. While there is a strong correlation (r(2) = 0.98) between delta(18)O and dD in the ice core samples, the regression slope (6.9) and mean d value (23.0) are significantly different than the global meteoric water line values. The resulting time-series ice core d profile contains distinct winter maxima and summer minima, with a yearly d amplitude of similar to 15 - 20parts per thousand. Local-scale processes that may affect d values preserved in the ice core are not consistent with the observed seasonal variability. Data from Central Asian monitoring sites in the Global Network of Isotopes in Precipitation (GNIP) have similar seasonal d changes. We suggest that regional-scale hydrological conditions, including seasonal changes in moisture source, transport, and recycling in the Caspian/ Aral Sea region, are responsible for the observed spatial and temporal d variability.

Fluid-related inclusions in Alpine high-pressure peridotite reveal trace element recycling during subduction-zone dehydration of serpentinized mantle (Cima di Gagnone, Swiss Alps).

Serpentinites release at sub-arc depths volatiles and several fluid-mobile trace elements found in arc magmas. Constraining element uptake in these rocks and defining the trace element composition of fluids released upon serpentinite dehydration can improve our understanding of mass transfer across subduction zones and to volcanic arcs. The eclogite-facies garnet metaperidotite and chlorite harzburgite bodies embedded in paragneiss of the subduction melange from Cima di Gagnone derive from serpentinized peridotite protoliths and are unique examples of ultramafic rocks that experienced subduction metasomatism and devolatilization. In these rocks, metamorphic olivine and garnet trap polyphase inclusions representing the fluid released during high-pressure breakdown of antigorite and chlorite. Combining major element mapping and laser-ablation ICP-MS bulk inclusion analysis, we characterize the mineral content of polyphase inclusions and quantify the fluid composition. Silicates, Cl-bearing phases, sulphides, carbonates, and oxides document post-entrapment mineral growth in the inclusions starting immediately after fluid entrapment. Compositional data reveal the presence of two different fluid types. The first (type A) records a fluid prominently enriched in fluid-mobile elements, with Cl, Cs, Pb, As, Sb concentrations up to 10(3) PM (primitive mantle), similar to 10(2) PM Tit Ba, while Rb, B, Sr, Li, U concentrations are of the order of 10(1) PM, and alkalis are similar to 2 PM. The second fluid (type B) has considerably lower fluid-mobile element enrichments, but its enrichment patterns are comparable to type A fluid. Our data reveal multistage fluid uptake in these peridotite bodies, including selective element enrichment during seafloor alteration, followed by fluid-rock interaction along with subduction metamorphism in the plate interface melange. Here, infiltration of sediment-equilibrated fluid produced significant enrichment of the serpentinites in As, Sb, B, Pb, an enriched trace element pattern that was then transferred to the fluid released at greater depth upon serpentine dehydration (type A fluid). The type B fluid hosted by garnet may record the composition of the chlorite breakdown fluid released at even greater depth. The Gagnone study-case demonstrates that serpentinized peridotites acquire water and fluid-mobile elements during ocean floor hydration and through exchange with sediment-equilibrated fluids in the early subduction stages. Subsequent antigorite devolatilization at subarc depths delivers aqueous fluids to the mantle wedge that can be prominently enriched in sediment-derived components, potentially triggering arc magmatism without the need of concomitant dehydration/melting of metasediments or altered oceanic crust.

The Chemical Mechanism of a Brown-Rot Decay Mimtic System and its Application in Paper Recycling Processes

This work is aimed at improving our current knowledge of the non-enzymatic inecl~anisins involved in brown-rot decay, as well as the exploration of potential applications of a brown-rot mimetic model system in paper recycling processes. The study was divided into two parts. The first part focussed on the chemical mechanisms involved in chelation and reduction of iron by a low molecular weight chelator (isolated from the brown-rot fungus Gloeophyllz~m tmbeum) and its model compound 2,3- dihydroxybenzoic acid (2,3-DHBA). Chelation as well as free radical generation mediated by this system were studied by ESR measurement. The results indicate that the effects of the chelator/iron ratio, the pH, and other reaction parameters on hydroxyl radical generation by a Fenton type system could be determined using ESR spin-trapping techniques. The results also support the hypothesis that superoxide radicals are involved in the chelator-mediated Fenton process. In the second part of the study, the effect of a chelator-mediated Fenton system for the improvement of deinking efficiency and the n~odification of fiber and paper properties was studied. For the deinking study, copy paper was laser printed with an identical standard pattern. Then repulping and flotation operations were performed to remove ink particles. Under properly controlled deinking conditions, the chelator mediated treatment (CMT) resulted in a reduction in dirt count over that of conventional deinking procedures with no significant loss of pulp strength. To study the effect of the chelator system treatment on the quality of pulp with different fines content, a fully bleached hardwood kraft pulp was beaten to different freeness levels and treated with the chelator-mediated free radical system. The result shows that virgin fiber and heavily beaten fiber respond differently to the free radical treatment. Unbeaten fibers become more flexible and easier to collapse after free radical treatment, while beaten fibers show a reduction in fines and small materials after mild free radical treatment.

(Table 1) Activity of alkali phosphatase in suspended matter at 20°C and environmental temperatures, and recycling time of organic phosphorus in the Barents and Norwegian seas

Alkali phosphatase activity and hydrochemical structure of waters in the Barents and Norwegian seas were investigated. In a sea with the seasonal bioproduction cycle alkali phosphatase activity is also seasonal, rising with trophic level of waters. At the end of hydrological and biological winter activity is practically zero. Alkali phosphatase activity is especially important in summer, when plankton has consumed winter supply of phosphate in the euphotic layer and nutrient limitation of primary production begins. In summer production and destruction cycle, apparent time for recycling of phosphorus by phosphatase in suspended matter in the euphotic layer of the Barents Sea and Norwegian Sea averages from 7 to 30 hours.

Reacting and Recycling

To a certain extent what this research is proposing is a return to local principles or to regionalism, which is able to employ place-specific tools and craftsmanship (local arts and their virtues) promoting and being innovative with traditional elements which belong to a particular place, and using tectonic and stereotomic logic. You can observe this, in the face of a destructive natural event. An immediate architectural reaction is produced in cooperation with the rest of the not affected territory. The cooperation of certain non-governmental organizations with other groups in the same collaborative cycle improves the recycling of ideas and city planning forms. These organizations cooperate in the development and implementation of cities and settlements that need a fast reaction when facing an unexpected disaster.

Multiphase Current Controlled Buck Converter with energy recycling Output Impedance Correction Circuit (OICC)

This work is related to the output impedance improvement of a Multiphase Buck converter with Peak Current Mode Control (PCMC) by means of introducing an additional power path that virtually increases the output capacitance during transients. Various solutions that can be employed to improve the dynamic behavior of the converter system exist, but nearly all solutions are developed for a Single Phase Buck converter with Voltage Mode Control (VMC), while in the VRM applications, due to the high currents, the system is usually implemented as a Multiphase Buck Converter with Current Mode Control. The Output Impedance Correction Circuit (OICC) is used to inject or extract a current n-1 times larger than the output capacitor current, thus virtually increasing n times the value of the output capacitance during the transients. Furthermore, this work extends the OICC concept to a Multiphase Buck Converter system while comparing proposed solution with the system that has n times bigger output capacitor. In addition, the OICC is implemented as a Synchronous Buck Converter with PCMC, thus reducing its influence on the system efficiency

Factors impacting the market share of Construction and Demolition (C&D) Waste recycling solutions

Current EU Directives force the Member States to assure by 2020 that 70% of the Construction and Demolition (C&D) waste is recovered instead of landfilled. While some countries have largely achieved this target, others still have a long way to go. For better understanding the differences arising from local disparities, six factors related to technical, economic, legislative and environmental aspects have been identified as crucial influences in the market share of C&D waste recycling solutions. These factors are able to identify the causes that limit the recycling rate of a certain region. Moreover, progress towards an efficient waste management can vary through the improvement of a single factor. This study provides the background for further fine-tuning the factors and their combination into a mathematical model for assessing the market share of C&D recycling solutions.

New Plaster Composite with Mineral Wool Fibres from CDW Recycling

Over the last decade the intense activity of the building sector has generated large quantities of construction and demolition waste (CDW). In particular, in Europe around 890 million tons of CDW is generated every year; however, only 50% of them are recycled. In Spain, over the last years 40 millions of tons of construction and demolition waste have been generated. On the other hand, since the implementation of the Technical Building Code regulation the use of mineral wools as building insulation materials has become a widespread solution in both rehabilitation and new construction works, and because of that, this kind of insulation waste is increasing. This research analyzes the potential of a new composite (gypsum and fiber waste) including several mineral wools waste into a plaster matrix. For this purpose, an experimental plan, characterizing the physical and mechanical behaviour as well as the Shore C hardness of the new composite, was elaborated fulfilling UNE Standards.

Optically enhanced photon recycling in mechanically stacked multijunction solar cells

Multijunction solar cells can be fabricated by mechanically bonding together component cells that are grown separately. Here, we present four-junction four-terminal mechanical stacks composed of GaInP/GaAs tandems grown on GaAs substrates and GaInAsP/GaInAs tandems grown on InP substrates. The component cells were bonded together with a low-index transparent epoxy that acts as an angularly selective reflector to the GaAs bandedge luminescence, while simultaneously transmitting nearly all of the subbandgap light. As determined by electroluminescence measurements and optical modeling, the GaAs subcell demonstrates a higher internal radiative limit and, thus, higher subcell voltage, compared with GaAs subcells without the epoxy reflector. The best cells demonstrate 38.8 ± 1.0% efficiency under the global spectrum at 1000 W/m2 and ~ 42% under the direct spectrum at ~100 suns. Eliminating the series resistance is the key challenge for further improving the concentrator cells.

RGS-r, a retinal specific RGS protein, binds an intermediate conformation of transducin and enhances recycling

G proteins regulate intracellular signaling by coupling a cycle of guanine nucleotide binding and hydrolysis to transient changes of cellular functions. The mechanisms that control the recycling of transducin, the “pace-setting” G protein that regulates mammalian phototransduction, are unclear. We show that a novel retinal specific RGS-motif protein specifically binds to an intermediate conformation involved in GTP hydrolysis by transducin and accelerates phosphate release and the recycling of transducin. This specific interaction further rationalizes the kinetics of the phototransduction cascade and provides a general hypothesis to explain the mechanism of interaction of RGS proteins with other G proteins.

Association of Rab25 and Rab11a with the Apical Recycling System of Polarized Madin–Darby Canine Kidney Cells

Recent evidence suggests that apical and basolateral endocytic pathways in epithelia converge in an apically located, pericentriolar endosomal compartment termed the apical recycling endosome. In this compartment, apically and basolaterally internalized membrane constituents are thought to be sorted for recycling back to their site of origin or for transcytosis to the opposite plasma membrane domain. We report here that in the epithelial cell line Madin–Darby Canine Kidney (MDCK), antibodies to Rab11a label an apical pericentriolar endosomal compartment that is dependent on intact microtubules for its integrity. Furthermore, this compartment is accessible to a membrane-bound marker (dimeric immunoglobulin A [IgA]) internalized from either the apical or basolateral pole, functionally defining it as the apical recycling endosome. We have also examined the role of a closely related epithelial-specific Rab, Rab25, in the regulation of membrane recycling and transcytosis in MDCK cells. When cDNA encoding Rab25 was transfected into MDCK cells, the protein colocalized with Rab11a in subapical vesicles. Rab25 transfection also altered the distribution of Rab11a, causing the coalescence of immunoreactivity into multiple denser vesicular structures not associated with the centrosome. Nevertheless, nocodazole still dispersed these vesicles, and dimeric IgA internalized from either the apical or basolateral membrane was detected in endosomes labeled with antibodies to both Rab11a and Rab25. Overexpression of Rab25 decreased the rate of IgA transcytosis and of apical, but not basolateral, recycling of internalized ligand. Conversely, expression of the dominant-negative Rab25T26N did not alter either apical recycling or transcytosis. These results indicate that both Rab11a and Rab25 associate with the apical recycling system of epithelial cells and suggest that Rab25 may selectively regulate the apical recycling and/or transcytotic pathways.