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T. E. Graedel Julian Allwood Jean‐Pierre Birat Matthias Buchert Christian Hagelüken Barbara K. Reck Scott F. Sibley Guido Sonnemann 《Journal of Industrial Ecology》2011,15(3):355-366
The recycling of metals is widely viewed as a fruitful sustainability strategy, but little information is available on the degree to which recycling is actually taking place. This article provides an overview on the current knowledge of recycling rates for 60 metals. We propose various recycling metrics, discuss relevant aspects of recycling processes, and present current estimates on global end‐of‐life recycling rates (EOL‐RR; i.e., the percentage of a metal in discards that is actually recycled), recycled content (RC), and old scrap ratios (OSRs; i.e., the share of old scrap in the total scrap flow). Because of increases in metal use over time and long metal in‐use lifetimes, many RC values are low and will remain so for the foreseeable future. Because of relatively low efficiencies in the collection and processing of most discarded products, inherent limitations in recycling processes, and the fact that primary material is often relatively abundant and low‐cost (which thereby keeps down the price of scrap), many EOL‐RRs are very low: Only for 18 metals (silver, aluminum, gold, cobalt, chromium, copper, iron, manganese, niobium, nickel, lead, palladium, platinum, rhenium, rhodium, tin, titanium, and zinc) is the EOL‐RR above 50% at present. Only for niobium, lead, and ruthenium is the RC above 50%, although 16 metals are in the 25% to 50% range. Thirteen metals have an OSR greater than 50%. These estimates may be used in considerations of whether recycling efficiencies can be improved; which metric could best encourage improved effectiveness in recycling; and an improved understanding of the dependence of recycling on economics, technology, and other factors. 相似文献
3.
Sandrine Poncet Armelle Delecluse Guido Anello ré Klier Georges Rapoport 《FEMS microbiology letters》1994,117(1):91-95
Abstract The genes encoding the CryIVB and CryIVD crystal polypeptides of B. thuringiensis subsp. israelensis were cloned indepently on a stable shuttle vector, and transfered into B. sphaericus 2297. Recombinant cells expressed the B. thuringiensis toxins during sporulation and were shown to be toxic to Aedes aegypti fourth instar larvae, whereas the parental strain was not. 相似文献
4.
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Sabrina Forveille Heng Zhou Allan Sauvat Lucillia Bezu Kevin Müller Peng Liu Laurence Zitvogel Gérard Pierron ?ystein Rekdal Oliver Kepp Guido Kroemer 《Cell cycle (Georgetown, Tex.)》2015,14(21):3506-3512
The oncolytic peptide LTX-315 has been designed for killing human cancer cells and turned out to stimulate anti-cancer immune responses when locally injected into tumors established in immunocompetent mice. Here, we investigated the question whether LTX-315 induces apoptosis or necrosis. Transmission electron microscopy or morphometric analysis of chromatin-stained tumor cells revealed that LTX-315 failed to induce apoptotic nuclear condensation and rather induced a necrotic phenotype. Accordingly, LTX-315 failed to stimulate the activation of caspase-3, and inhibition of caspases by means of Z-VAD-fmk was unable to reduce cell killing by LTX-315. In addition, 2 prominent inhibitors of regulated necrosis (necroptosis), namely, necrostatin-1 and cycosporin A, failed to reduce LTX-315-induced cell death. In conclusion, it appears that LTX-315 triggers unregulated necrosis, which may contribute to its pro-inflammatory and pro-immune effects. 相似文献
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Dario Cremaschi Giuliano Meyer Guido Bottà Carlo Rossetti 《The Journal of membrane biology》1987,95(3):219-228
Summary In the epithelium of rabbit gallbladder, in the nominal absence of bicarbonate, intracellular Cl– activity is about 25mm, about 4 times higher than intracellular Cl– activity at the electrochemical equilibrium. It is essentially not affected by 10–4
m acetazolamide and 10–4
m 4-acetamido-4-isothiocyanostilbene-2,2-disulfonate (SITS) even during prolonged exposures; it falls to the equilibrium value by removal of Na+ from the lumen without significant changes of the apical membrane potential difference. Both intracellular Cl– and Na+ activities are decreased by luminal treatment with 25mm SCN–; the initial rates of change are not significantly different. In addition, the initial rates of change of intracellular Cl– activity are not significantly different upon Na+ or Cl– entry block by the appropriate reduction of the concentration of either ion in the luminal solution. Luminal K+ removal or 10–5
m bumetanide do not affect intracellular Cl– and Na+ activities or Cl– influx through the apical membrane. It is concluded that in the absence of bicarbonate NaCl entry is entirely due to a Na+–Cl– symport on a single carrier which, at least under the conditions tested, does not cotransport K+. 相似文献
8.
Dario Cremaschi Giuliano Meyer Carlo Rossetti Guido Bottà Paola Palestini 《The Journal of membrane biology》1987,95(3):209-218
Summary Cl– influx at the luminal border of the epithelium of rabbit gallbladder was measured by 45-sec exposures to36Cl– and3H-sucrose (as extracellular marker). Its paracellular component was evaluated by the use of 25mm SCN– which immediately and completely inhibits Cl– entry into the cell. Cellular influx was equal to 16.7eq cm–2 hr–1 and decreased to 8.5eq cm–2 hr–1 upon removal of HCO
3
–
from the bathing media and by bubbling 100% O2 for 45 min. When HCO
3
–
was present, cellular influx was again about halved by the action of 10–4
m acetazolamide, 10–5 to 10–4
m furosemide, 10–5 to 10–4
m 4-acetamido-4-isothiocyanostilbene-2,2-disulfonate (SITS), 10–3
m amiloride. The effects of furosemide and SITS were tested at different concentrations of the inhibitor and with different exposure times: they were maximal at the concentrations reported above and nonadditive. In turn, the effects of amiloride and SITS were not additive. Acetazolamide reached its maximal action after an exposure of about 2 min. When exogenous HCO
3
–
was absent, the residual cellular influx was insensitive to acetazolamide, furosemide and SITS. When exogenous HCO
3
–
was present in the salines, Na+ removal from the mucosal side caused a slow decline of cellular Cl– influx; conversely, it immediately abolished cellular Cl– influx in the absence of HCO
3
–
. In conclusion, about 50% of cellular influx is sensitive to HCO
3
–
, inhibitable by SCN–, acetazolamide, furosemide, SITS and amiloride and furthermore slowly dependent on Na+. The residual cellular influx is insensitive to bicarbonate, inhibitable by SCN–, resistant to acetazolamide, furosemide, SITS and amiloride, and immediately dependent on Na+. Thus, about 50% of apical membrane NaCl influx appears to result from a Na+/H+ and Cl–/HCO
3
–
exchange, whereas the residual influx seems to be due to Na+–Cl– contranport on a single carrier. Whether both components are simultaneously present or the latter represents a cellular homeostatic counterreaction to the inhibition of the former is not clear. 相似文献
9.
Human elongation factor 1α: a polymorphic and conserved multigene family with multiple chromosomal localizations 总被引:1,自引:0,他引:1
10.
Noninvasive determination of ulnar stiffness from mechanical response--in vivo comparison of stiffness and bone mineral content in humans 总被引:1,自引:0,他引:1
C R Steele L J Zhou D Guido R Marcus W L Heinrichs C Cheema 《Journal of biomechanical engineering》1988,110(2):87-96
An approach referred to as Mechanical Response Tissue Analysis (MRTA) has been developed for the noninvasive determination of mechanical properties of the constituents of the intact limb. Of specific interest in the present study is the bending stiffness of the ulna. The point mechanical impedance properties in the low frequency regime, between 60 and 1,600 Hz are used. The procedure requires a proper design of the probe for good contact of the skin at midshaft and proper support of the proximal and distal ends of the forearm to obtain an approximation to "simple support" of the ulna. A seven-parameter model for the mechanical response is then valid, which includes the first mode of anterior-posterior beam bending of the ulna, the damping and spring effect of the soft tissue between probe and bone, and the damping of musculature. A dynamic analyzer (HP3562A) provides in seconds the impedance curve and the pole-zero curve fit. The physical parameters are obtained from a closed-form solution in terms of the curve-fit parameters. The procedure is automated and is robust and analytically reliable at about the five percent level. Some 80 human subjects have been evaluated by this mechanical response system and by the Norland single photon absorptiometer, providing for the first time in vivo, a comparison of elastic bending stiffness (ulna) and bone mineral content (radius). Three functional parameters of potential clinical value are the cross-sectional bending stiffness EI, the axial load capability Pcr (Euler buckling load) and the bone "sufficiency" S, defined as the ratio of Pcr to body weight. The correlation between EI and bone mineral (r = 0.81) is only slightly less than previous in vitro results with both measurements on the same bone (r = 0.89). When sufficiency is taken into consideration, the correlation of Pcr and bone mineral content is improved (r = 0.89). An implication is that "quality" of bone is a factor which is not indicated by bone mineral content but which is indicated by stiffness. Bone mineral is necessary for proper stiffness but not sufficient. Therefore mechanical measurement should provide a new dimension to be used toward a better understanding of the factors related to bone health and disease. 相似文献