Renal transplant candidates with donor‐specific alloantibody (DSA) have increased risk of antibody‐mediated allograft injury. The goal of this study was to correlate the risk of antibody‐mediated ...rejection (AMR), transplant glomerulopathy (TG) and graft survival with the baseline DSA level (prior to initiation of pretransplant conditioning). These analyses include 119 positive crossmatch (+XM) compared to 70 negative crossmatch (−XM) transplants performed between April 2000 and July 2007. Using a combination of cell‐based crossmatch tests, DSA level was stratified into very high +XM, high +XM, low +XM and −XM groups. In +XM transplants, increasing DSA level was associated with increased risk for AMR (HR = 1.76 1.51, 2.07, p = 0.0001) but not TG (p = 0.18). We found an increased risk for both early and late allograft loss associated with very high DSA (HR = 7.71 2.95, 20.1, p = 0.0001). Although lower DSA recipients commonly developed AMR and TG, allograft survival was similar to that of −XM patients (p = 0.31). We conclude that the baseline DSA level correlates with risk of early and late alloantibody‐mediated allograft injury. With current protocols, very high baseline DSA patients have high rates of AMR and poor long‐term allograft survival highlighting the need for improved therapy for these candidates.
Although the risk for acute ABMR is associated with high baseline DSA level in +XM recipients, the incidence of TG in +XM recipients is similar regardless of baseline DSA level.
CO
2
, CH
4
, and N
2
O are recognised as the most important greenhouse gases, the concentrations of which increase rapidly through human activities. Space-borne integrated path differential ...absorption lidar allows global observations at day and night over land and water surfaces in all climates. In this study we investigate potential sources of measurement errors and compare them with the scientific requirements. Our simulations reveal that moderate-size instruments in terms of telescope aperture (0.5–1.5 m) and laser average power (0.4–4 W) potentially have a low random error of the greenhouse gas column which is 0.2% for CO
2
and 0.4% for CH
4
for soundings at 1.6 μm, 0.4% for CO
2
at 2.1 μm, 0.6% for CH
4
at 2.3 μm, and 0.3% for N
2
O at 3.9 μm. Coherent detection instruments are generally limited by speckle noise, while direct detection instruments suffer from high detector noise using current technology. The wavelength selection in the vicinity of the absorption line is critical as it controls the height region of highest sensitivity, the temperature cross-sensitivity, and the demands on frequency stability. For CO
2
, an error budget of 0.08% is derived from our analysis of the sources of systematic errors. Among them, the frequency stability of ± 0.3 MHz for the laser transmitter and spectral purity of 99.9% in conjunction with a narrow-band spectral filter of 1 GHz (FWHM) are identified to be challenging instrument requirements for a direct detection CO
2
system operating at 1.6 μm.
The Alt–Grassberger–Sandhas equations for the five-body η−4N problem are solved for the case of the driving ηN and NN potentials limited to s-waves. Separable expansion of the transition amplitudes ...in all different subsystems is employed to convert the five-body equations into the effective two-body form. Numerical results are presented for the η4He scattering length.
Active remote sensing is a promising technique to close the gaps that exist in global measurement of atmospheric carbon dioxide sources, sinks and fluxes. Several approaches are currently under ...development. Here, an experimental setup of an integrated path differential absorption lidar (IPDA) is presented, operating at 1.57 μm using direct detection. An injection seeded KTP-OPO system pumped by a Nd:YAG laser serves as the transmitter. The seed laser is actively stabilized by means of a CO
2
reference cell. The line-narrowed OPO radiation yields a high spectral purity, which is measured by means of a long path absorption cell. First measurements of diurnal variations of the atmospheric CO
2
mixing ratio using a topographic target were performed and show good agreement compared to simultaneously taken measurements of an in situ device. A further result is that the required power reference measurement of each laser pulse in combination with the spatial beam quality is a critical point of this method. The system described can serve as a testbed for further investigations of special features of the IPDA technique.
The Alt–Grassberger–Sandhas equations for the five-body problem are solved for the case of the driving two-body potentials limited to
s
-waves. The separable pole expansion method is employed to ...convert the equations into the effective quasi-two-body form. Numerical results are presented for five identical bosons as well as for the system containing an
η
-meson and four nucleons. Accuracy of the separable expansion is investigated. It is shown that both in
(
1
+
4
)
and
(
2
+
3
)
fragmentation, the corresponding eigenvalues decrease rather rapidly, what, combined with the alternation of their signs, leads to rather good convergence of the results. For the
η
-
4
N
system the crucial influence of the subthreshold behavior of the
η
N
amplitude on the
η
-nuclear low-energy interaction is discussed.
A high-performance airborne water vapor differential absorption lidar has been developed during the past years. This system uses a four-wavelength/three-absorption line measurement scheme in the ...935 nm H
2
O absorption band to cover the whole troposphere and lower stratosphere simultaneously. Additional high spectral resolution aerosol and depolarization channels allow precise aerosol characterization. This system is intended to demonstrate a future space-borne instrument. For the first time, it realizes an output power of up to 12 W at a high wall-plug efficiency using diode-pumped solid-state lasers and nonlinear conversion techniques. Special attention was given to a rugged optical layout. This paper describes the system layout and technical realization. Key performance parameters are given for the different subsystems.
Methane is the third most important greenhouse gas in the atmosphere after water vapour and carbon dioxide. A major handicap to quantify the emissions at the Earth's surface in order to better ...understand biosphere-atmosphere exchange processes and potential climate feedbacks is the lack of accurate and global observations of methane. Space-based integrated path differential absorption (IPDA) lidar has potential to fill this gap, and a Methane Remote Lidar Mission (MERLIN) on a small satellite in polar orbit was proposed by DLR and CNES in the frame of a German-French climate monitoring initiative. System simulations are used to identify key performance parameters and to find an advantageous instrument configuration, given the environmental, technological, and budget constraints. The sensitivity studies use representative averages of the atmospheric and surface state to estimate the measurement precision, i.e. the random uncertainty due to instrument noise. Key performance parameters for MERLIN are average laser power, telescope size, orbit height, surface reflectance, and detector noise. A modest-size lidar instrument with 0.45 W average laser power and 0.55 m telescope diameter on a 506 km orbit could provide 50-km averaged methane column measurement along the sub-satellite track with a precision of about 1% over vegetation. The use of a methane absorption trough at 1.65 μm improves the near-surface measurement sensitivity and vastly relaxes the wavelength stability requirement that was identified as one of the major technological risks in the pre-phase A studies for A-SCOPE, a space-based IPDA lidar for carbon dioxide at the European Space Agency. Minimal humidity and temperature sensitivity at this wavelength position will enable accurate measurements in tropical wetlands, key regions with largely uncertain methane emissions. In contrast to actual passive remote sensors, measurements in Polar Regions will be possible and biases due to aerosol layers and thin ice clouds will be minimised.
We report a measurement of the spin polarization of the recoiling neutron in deuterium photodisintegration, utilizing a new large acceptance polarimeter within the Crystal Ball at MAMI. The measured ...photon energy range of 300-700 MeV provides the first measurement of recoil neutron polarization at photon energies where the quark substructure of the deuteron plays a role, thereby providing important new constraints on photodisintegration mechanisms. A very high neutron polarization in a narrow structure centered around E_{γ}∼570 MeV is observed, which is inconsistent with current theoretical predictions employing nucleon resonance degrees of freedom. A Legendre polynomial decomposition suggests this behavior could be related to the excitation of the d^{*}(2380) hexaquark.
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