4,237 research outputs found
An FES-assisted gait training system for hemiplegic stroke patients based on inertial sensors
New multiplexing scheme for monitoring fiber optic Bragg grating sensors in the coherence domain
A new multiplexing scheme for monitoring fiber optic Bragg gratings in the coherence domain has been developed. Grating pairs with different grating distances are distributed along a fiber line, and interference between their reflections is monitored with a scanning Michelson interferometer. The Bragg wavelength of the individual sensor elements is determined from the interference signal frequency
Experimentally Feasible Security Check for n-qubit Quantum Secret Sharing
In this article we present a general security strategy for quantum secret
sharing (QSS) protocols based on the HBB scheme presented by Hillery, Bu\v{z}ek
and Berthiaume [Phys. Rev A \textbf{59}, 1829 (1999)]. We focus on a
generalization of the HBB protocol to communication parties thus including
-partite GHZ states. We show that the multipartite version of the HBB scheme
is insecure in certain settings and impractical when going to large . To
provide security for such QSS schemes in general we use the framework presented
by some of the authors [M. Huber, F. Minert, A. Gabriel, B. C. Hiesmayr, Phys.
Rev. Lett. \textbf{104}, 210501 (2010)] to detect certain genuine partite
entanglement between the communication parties. In particular, we present a
simple inequality which tests the security.Comment: 5 pages, submitted to Phys. Rev.
Glutathione treatment protects the rat liver against injury after warm ischemia and Kupffer cell activation
Background/Aim: The generation of reactive oxygen species by activated Kupffer cells (KC) may contribute to reperfusion injury of the liver during liver transplantation or resection. The aim of our present studies was to investigate (1) prevention of hepatic reperfusion injury after warm ischemia by administration of the antioxidant glutathione (GSH) and (2) whether GSH confers protection through influences on KC toxicity. Methods: Isolated perfused rat livers were subjected to 1 h of warm ischemia followed by 90 min of reperfusion without (n = 5) or with GSH or catalase (n = 4-5 each). Selective KC activation by zymosan (150 mug/ml) in continuously perfused rat livers was used to investigate KC-related liver injury. Results: Postischemic infusion of 0.1, 0.5, 1.0 and 2.0 mM GSH, but not 0.05 mM GSH prevented reperfusion injury after warm ischemia as indicated by a marked reduction of sinusoidal LDH efflux by up to 83 +/- 13% (mean +/- SD; p < 0.05) and a concomitant significant improvement of postischemic bile flow by 58 +/- 27% (p < 0.05). A similar protection was conveyed by KC blockade with gadolinium chloride indicating prevention of KC-related reperfusion injury by postischemic GSH treatment. Postischemic treatment with catalase (150 U/ml) resulted in a reduction of LDH efflux by 40 +/- 9% (p < 0.05). Accordingly, catalase as well as GSH (0.1-2.0 mM) nearly completely prevented the increase in LDH efflux following selective :KC activation by zymosan in continously perfused rat livers. Conclusion: Postischemic administration of GSH protects the liver against reperfusion injury after warm ischemia. Detoxification of KC-derived hydrogen peroxide seem to be an important feature of the protective mechanisms. Copyright (C) 2002 S. Karger AG, Basel
Legislative Note: Micigan\u27s Criminal Sexual Assault Law
Under increasing pressure from women\u27s rights groups and other reform organizations, the Michigan legislature has re-evaluated its centenarian rape statute, found it inadequate for the realities of the mid-twentieth century, and enacted a new sexual assault act. While people may refer to the act as the new rape law, it should be noted at the outset that the statute is intended to prohibit a variety of sexual acts which involve criminal assault. Michigan\u27s new criminal sexual assault law was formulated to distinguish among degrees of violence as motivated by hostility rather than passion; rape, like other crimes, is more heinous in certain contexts than others. The new law acknowledges that criminal sexual conduct is generally a premeditated crime of violence rather than a crime provoked by the victim\u27s behavior. The victim is no longer required to resist. Where force is used, it is now presumed that the victim did not consent. Similarly, evidence is limited to that which applies to the specific crime rather than evidence concerning the victim\u27s past sexual behavior. This note will analyze the specific provisions of the new bill and discuss the policies behind the evidentiary changes
Archangelopsis jagoa, a new species of benthic siphonophore (Physonectae, Rhodaliidae) collected by submersible in the Red Sea
A new species of rhodaliid siphonophore, Archangelopsis jagoa sp, nov., is described from three specimens collected at depths between 250 and 370 m in the Gulf of Akaba, Red Sea, by the submersible JAGO. Comparisons are made with the established species of that genus and observations, both in situ and on the living animals in captivity, are reported
GSH Attenuates Organ Injury and Improves Function after Transplantation of Fatty Livers
Ischemia-reperfusion injury (IRI) is increased after transplantation of steatotic livers. Since those livers are increasingly used for transplantation, protective strategies must be developed. Reactive oxygen species (ROS) play a key role in hepatic IRI. In lean organs, glutathione (GSH) is an efficient scavenger of ROS, diminishing IRI. The aim of this study was to evaluate whether GSH also protects steatotic allografts from IRI following transplantation. Fatty or lean livers were explanted from 10-week-old obese or lean Zucker rats and preserved (obese 4 h, lean 24 h) in hypothermic University of Wisconsin solution. Arterialized liver transplantation was then performed in lean syngeneic Zucker rats. Recipients of fatty livers were treated with GSH (200 mu mol/h/kg) or saline during reperfusion (2 h, n = 5). Parameters of hepatocellular damage and bile flow were measured. Transplantation of steatotic livers enhanced early reperfusion injury compared to lean organs as measured by increased aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase plasma levels. Bile flow was also reduced in steatotic grafts. Intravenous administration of GSH effectively decreased liver damage in fatty allografts and resulted in improved bile flow. Intravenous application of GSH effectively reduces early IRI in steatotic allografts and improves recovery of these marginal donor organs following transplantation. Copyright (C) 2010 S. Karger AG, Base
The halt of deep convection in the Greenland Sea: A natural experiment for the study of their causes and effects
There are only a few sites where the deep ocean is ventilated from the surface. The responsible process known as
deep convection is recognized to be a key process on the Earth’s climate system, but still it is scarcely observed, and
its good representation by global oceanographic and climate models remains unclear. In the Arctic Ocean, the halt
of deep convection in the Greenland Sea during the last three decades serves as a natural experiment to study: (1)
the conditions that drive the occurrence or not of deep convection and (2) the effects of the halt of deep convection
on the thermohaline properties of the deep water masses and circulation both locally and in adjacent ocean basins.
Combining oceanic and atmospheric in-situ data together with reanalysis data, we observe that not only on average
the winter net heat losses from the ocean to the atmosphere (Qo) have decreased during the last three decades in the
Greenland Sea ( Qo (before the 1980s- after the 1980s) = 25 Wm-2) but the intensity and number of strong cooling
events (Qo 800Wm-2). This last value for convection reaching 2000 m in the Greenland Sea seems critical to
make the mixed layer deepening from being a non-penetrative process to one arrested by baroclinic instabilities.
Besides, changes in the wind stress curl and preconditioning for deep convection have occurred, hindering also the
occurrence of deep convection. Concerning the effects of the halt of deep convection, hydrographic data reveal that
the temperature between 2000 meters depth and the sea floor has risen by 0.3 C in the last 30 years, which is ten
times higher than the temperature increase in the global ocean on average, and salinity rose by 0.02 because import
of relatively warm and salty Arctic Ocean deep waters continued. The necessary transports to explain the observed
changes suggest an increase of Arctic Ocean deep water transport that would have compensated the decrease in
deep water formation rate after the 1980s. The effects of these changes in adjacent basins remain unstudied, but
the bottom waters seem to be upwelled towards the slope and the Jan Mayen ridge, being an exit for the Greenland
Sea deep waters.0,000
Combining tower mixing ratio and community model data to estimate regional-scale net ecosystem carbon exchange by boundary layer inversion over 4 flux towers in the U.S.A.
We evaluated an idealized boundary layer (BL) model with simple parameterizations using vertical transport information from community model outputs (NCAR/NCEP Reanalysis and ECMWF Interim Analysis) to estimate regional-scale net CO2 fluxes from 2002 to 2007 at three forest and one grassland flux sites in the United States. The BL modeling approach builds on a mixed-layer model to infer monthly average net CO2 fluxes using high-precision mixing ratio measurements taken on flux towers. We compared BL model net ecosystem exchange (NEE) with estimates from two independent approaches. First, we compared modeled NEE with tower eddy covariance measurements. The second approach (EC-MOD) was a data-driven method that upscaled EC fluxes from towers to regions using MODIS data streams. Comparisons between modeled CO2 and tower NEE fluxes showed that modeled regional CO2 fluxes displayed interannual and intra-annual variations similar to the tower NEE fluxes at the Rannells Prairie and Wind River Forest sites, but model predictions were frequently different from NEE observations at the Harvard Forest and Howland Forest sites. At the Howland Forest site, modeled CO2 fluxes showed a lag in the onset of growing season uptake by 2 months behind that of tower measurements. At the Harvard Forest site, modeled CO2 fluxes agreed with the timing of growing season uptake but underestimated the magnitude of observed NEE seasonal fluctuation. This modeling inconsistency among sites can be partially attributed to the likely misrepresentation of atmospheric transport and/or CO2gradients between ABL and the free troposphere in the idealized BL model. EC-MOD fluxes showed that spatial heterogeneity in land use and cover very likely explained the majority of the data-model inconsistency. We show a site-dependent atmospheric rectifier effect that appears to have had the largest impact on ABL CO2 inversion in the North American Great Plains. We conclude that a systematic BL modeling approach provided new insights when employed in multiyear, cross-site synthesis studies. These results can be used to develop diagnostic upscaling tools, improving our understanding of the seasonal and interannual variability of surface CO2 fluxes
Ischemic preconditioning attenuates portal venous plasma concentrations of purines following warm liver ischemia in man
Background/Aims: Degradation of adenine nucleotides to adenosine has been suggested to play a critical role in ischemic preconditioning (IPC). Thus, we questioned in patients undergoing partial hepatectomy whether (i) IPC will increase plasma purine catabolites and whether (ii) formation of purines in response to vascular clamping (Pringle maneuver) can be attenuated by prior IPC. Methods: 75 patients were randomly assigned to three groups: group I underwent hepatectomy without vascular clamping; group II was subjected to the Pringle maneuver during resection, and group III was preconditioned (10 min ischemia and 10 min reperfusion) prior to the Pringle maneuver for resection. Central, portal venous and arterial plasma concentrations of adenosine, inosine, hypoxanthine and xanthine were determined by high-performance liquid chromatography. Results: Duration of the Pringle maneuver did not differ between patients with or without IPC. Surgery without vascular clamping had only a minor effect on plasma purine transiently increased. After the Pringle maneuver alone, purine plasma concentrations were most increased. This strong rise in plasma purines caused by the Pringle maneuver, however, was significantly attenuated by IPC. When portal venous minus arterial concentration difference was calculated for inosine or hypoxanthine, the respective differences became positive in patients subjected to the Pringle maneuver and were completely prevented by preconditioning. Conclusion: These data demonstrate that (i) IPC increases formation of adenosine, and that (ii) the unwanted degradation of adenine nucleotides to purines caused by the Pringle maneuver can be attenuated by IPC. Because IPC also induces a decrease of portal venous minus arterial purine plasma concentration differences, IPC might possibly decrease disturbances in the energy metabolism in the intestine as well. Copyright (C) 2005 S. Karger AG, Basel
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