The reactor antineutrinos are used for the precise measurement of oscillation parameters in the 3-neutrino model, and also used to investigate active-sterile neutrino mixing sensitivity in the
3
+
1
...neutrino framework. In the present work, we study the feasibility of sterile neutrino search with the indian scintillator matrix for reactor anti-neutrino (ISMRAN) experimental set-up using electron antineutrinos (
ν
¯
e
) produced from reactor as a source. The so-called
3
+
1
scenario is considered for active-sterile neutrino mixing, which leads to projected exclusion curves in the sterile neutrino mass and mixing angle plane. The analysis is performed considering both the reactor and detector related parameters. It is found that, the ISMRAN set-up can observe the active-sterile neutrino mixing sensitivity for
sin
2
2
θ
14
≥
0.064
and
Δ
m
41
2
=
1.0
eV
2
at
90
%
confidence level for an exposure of 1 ton-year by using neutrinos produced from the DHRUVA reactor with thermal power of
100
MW
th
. It is also observed that, there is a significant improvement of the active-sterile neutrino mixing parameter
sin
2
2
θ
14
to
∼
0.03 at the same
Δ
m
41
2
by putting the ISMRAN detector set-up at a distance of 20 m from the compact proto-type fast breeder reactor facility with thermal power of 1250
MW
th
.
Image analysis and numerical simulation algorithms are introduced to analyze the micro‐structure, transport, and electrochemical performance of thin, low platinum loading inkjet printed electrodes. A ...local thresholding algorithm is used to extract the catalyst layer pore morphology from focused ion beam scanning electron microscopy (FIB‐SEM) images. n‐point correlation functions, such as auto‐correlation, chord length, and pore‐size distribution are computed to interpret the micro‐structure variations between different images of the same catalyst layer. Pore size distributions are in agreement with experimental results. The catalyst layer exhibits anisotropy in the through‐plane direction, and artificial anisotropy in the FIB direction due to low slicing resolution. Microscale numerical mass transport simulations show that transport predictions are affected by image resolution and that a minimum domain size of 200 nm is needed to estimate transport properties. A micro‐scale electrochemical model that includes a description of the ionomer film resistance and a multi‐step electrochemical reaction model for the oxygen reduction reaction is also presented. Results show that the interfacial mass transport resistance in the ionomer film has the largest effect on the electrochemical performance.
In this work, we present an analysis of the sensitivity to the active-sterile neutrino mixing with the Indian Scintillator Matrix for Reactor Anti-Neutrino (ISMRAN) experimental setup at very short ...baseline. The 3 ( active ) + 1 (sterile) neutrino oscillation model is considered to study the sensitivity of the active-sterile neutrino in the mass splitting and mixing angle plane. In this article, we have considered the measurement of electron antineutrino induced events employing a single detector which can be placed either at a single position or moved between a near and far positions from the given reactor core. Results extracted in the later case are independent of the theoretical prediction of the reactor anti-neutrino spectrum and detector related systematic uncertainties. Our analysis shows that the results obtained from the measurement carried out at combination of the near and far detector positions are improved significantly at higher Δm412 compared to the ones obtained with the measurement at a single detector position only. It is found that the best possible combination of near and far detector positions from a 100 MWth power DHRUVA research reactor core are 7 m and 9 m, respectively, for which ISMRAN setup can exclude in the range 1.4 eV2 ≤ Δ m412 ≤ 4.0 eV2 of reactor antineutrino anomaly region along with the present best-fit point of active-sterile neutrino oscillation parameters. At those combinations of detector positions, the ISMRAN setup can observe the active sterile neutrino oscillation with a 95% confidence level provided that sin22θ14 ≥ 0.09 at Δm412 = 1 eV2 for an exposure of 1 ton-yr. The active-sterile neutrino mixing sensitivity can be improved by about 22% at the same exposure by placing the detector at near and far distances of 15 m and 17 m, respectively, from the compact proto-type fast breeder reactor (PFBR) facility which has a higher thermal power of 1250 MWth.
T cells play a dual role in transplantation: They mediate transplant rejection and are crucial for virus control. Memory T cells generated in response to pathogens can cross‐react to alloantigen, a ...phenomenon called heterologous immunity. Virus‐specific CD8+ T cells cross‐reacting to donor‐alloantigen might affect alloimmune responses and hamper tolerance induction following transplantation. Here, we longitudinally studied these cross‐reactive cells in peripheral blood of 25 kidney transplant recipients with a cytomegalovirus and/or Epstein‐Barr virus infection. Cross‐reactive T cells were identified by flow cytometry as virus‐specific T cells that proliferate in response to donor cells in a mixed‐lymphocyte reaction. In 13 of 25 patients, we found cross‐reactivity to donor cells for at least 1 viral epitope before (n = 7) and/or after transplantation (n = 8). Cross‐reactive T cells were transiently present in the circulation, and their precursor frequency did not increase following transplantation or viral infection. Cross‐reactive T cells expressed interferon‐γ and CD107a in response to both alloantigen and viral peptide and resembled virus‐specific T cells in phenotype and function. Their presence was not associated with impaired renal function, proteinuria, or rejection. In conclusion, virus‐specific T cells that cross‐react to donor‐alloantigen are transiently detectable in the circulation of kidney transplant recipients.
Combining mixed‐lymphocyte reaction and tetramer staining, the authors find that kidney transplant recipients infected with cytomegalovirus and/or Epstein–Barr virus frequently have virus‐specific T cells that cross‐react to donor‐alloantigen and that these cross‐reactive cells are functional and transiently present in the circulation. See the editorial from Ford on page 1348.
Background.
Pneumocystis jiroveci pneumonia (PCP) is an important cause of morbidity and mortality in renal transplant recipients (RTRs). Chemoprophylaxis with trimethoprim/sulphamethoxazole is ...recommended during the early post-transplantation period, but the optimal duration has not been determined and a main drawback of chemoprophylaxis is the development of resistance of the commensal faecal flora. A cluster outbreak of PCP occurred in our outpatient Renal Transplant Unit. We aimed to investigate risk factors for PCP in RTRs to determine who should receive long-term chemoprophylaxis.
Methods. In a case-control study, we investigated common demographic variables and immunological parameters. Nine PCP cases diagnosed between August 2006 and April 2007 were matched with 18 control patients, who did not develop PCP, received their transplant in the same time-period and had a similar follow-up period with a comparable immunosuppressive drug regimen.
Results. The median time from transplantation to PCP was 19 months. We observed no significant differences in gender, age, donor type or number of rejections. In PCP cases, the median lymphocyte count just before PCP diagnosis was 0.49 (0.26-0.68), which was significantly reduced compared to the control patients after a similar follow-up period (median 1.36, 0.59-3.04, P = 0.002). This lymphocytopaenia was chronic and existed in most patients already for many months. CD4+ T-cell counts were also significantly reduced in the PCP cases. We found no difference in the Th1, Th2 and Th17 subsets between PCP cases and control patients.
Conclusion. Long-term prophylactic therapy for PCP may be indicated for RTR with persistent severe lymphocytopaenia.
Summary
Rabbit anti‐thymocyte globulin (rATG) induces a long‐lasting lymphocytopenia. CD4+ T cells remain depleted for up to 2 years, whereas the CD8+ T cell compartment is refilled rapidly by highly ...differentiated CD27‐CD45RA+CD57+effector‐type cells. Because the presence of these highly differentiated CD8+ T cells has been associated with cytomegalovirus (CMV) infection, we questioned to what extent restoration of CMV T cell immunity contributes to the re‐emergence of T cells following rATG treatment. We compared T cell repopulation in six CMV‐seropositive patients with CMV reactivation (reactivating CMV+) to that in three CMV+ patients without reactivation (non‐reactivating CMV+), and to that in three CMV‐seronegative recipients receiving a kidney from a CMV‐seronegative donor (CMV−/−). All patients received rATG because of acute allograft rejection. Total CD4 and CD8 counts, frequency and phenotype of virus‐specific CD8+ T cells were determined. In reactivating CMV+ patients, total CD8+ T cells reappeared rapidly, whereas in non‐reactivating CMV+ patients they lagged behind. In CMV−/− patients, CD8+ T cell counts had not yet reached pretransplant levels after 2 years. CMV reactivation was indeed followed by a progressive accumulation of CMV‐specific CD8+ T cells. During lymphocytopenia following rATG treatment, serum interleukin (IL)‐7 levels were elevated. Although this was most prominent in the CMV‐seronegative patients, it did not result in an advantage in T cell repopulation in these patients. Repopulated CD8+ T cells showed increased skewing in their Vβ repertoire in both CMV−/− and reactivating CMV‐seropositive patients. We conclude that rapid T cell repopulation following rATG treatment is driven mainly by CMV.
Water management remains a key challenge in polymer-electrolyte fuel cells. In this work, a pseudo 3-D (1+2D) model is developed to account better for changes of water management along the channel, ...as well as verify the possibilities of using differential cells for data capture and translation to integral cell performance. An accurate 2-D membrane-electrode-assembly model is developed for differential cell modeling, which is combined with an along-the-channel stepping algorithm to account for down the channel changes in pressure, temperature, reactant concentration, and relative humidity. Variations in cell performance along the channel due to changes in operating conditions are characterized quantitatively and optimized, where drier feed conditions demonstratively require such an approach. Overall, the study identifies gaps between differential and integral cells including those related to flow velocity and highlights the need for better models to understand and link integral cell performance and water management.
To evaluate dose calculation accuracy of various algorithms in lung equivalent inhomogeneity comprising tumor within it and comparison with Gafchromic film data.
Gafchromic film measured central axis ...absorbed dose in lung insert (-700 Hounsfield unit HU), in racemosa wood cylindrical inhomogeneity (-725 HU) and at three surfaces of tumor (-20 HU) created in cylindrical inhomogeneity, put in the cavity of computerized imaging reference systems (CIRS) thorax phantom were compared with convolution (CON), superposition (SP), fast SP (FSP), and X-ray voxel Monte Carlo (XVMC) algorithms calculated dose using 6 MV beams of field size 2 cm × 2 cm, 3 cm × 3 cm, 4 cm × 4 cm, 5 cm × 5 cm, and 8 cm × 8 cm.
XVMC was in good agreement with film measured results for all selected field sizes except 3 cm × 3 cm. SP under estimated by 5.7% at the center of the lung insert while deviation up to 6% was found at the cent of wood inhomogeneity in 2 cm × 2 cm. Except CON, increase in dose from proximal to the central surface of the tumor and then dose falloff from central to the distal surface for field size 2 cm × 2 cm to 4 cm × 4 cm was recorded. The change in film measured percentage depth dose from 2 cm × 2 cm to 3 cm × 3 cm field sizes was found -8% however for consecutive field size(s) larger than 3 cm × 3 cm this difference was less. CON and FSP produced overestimated results.
Out of four algorithms, XVMC found consistent with measured data. The electronic disequilibrium within and at the interface of inhomogeneity make the accurate dose predictions difficult. These limitations results in deviations from the expected results of the treatments.
In kidney transplantation, donor HLA antibodies are a risk factor for graft loss. Accessibility of donor eplets for HLA antibodies is predicted by the ElliPro score. The clinical usefulness of those ...scores in relation to transplant outcome is unknown. In a large Dutch kidney transplant cohort, Ellipro scores of pretransplant donor antibodies that can be assigned to known eplets (donor epitope specific HLA antibodies DESAs) were compared between early graft failure and long surviving deceased donor transplants. We did not observe a significant Ellipro score difference between the two cohorts, nor significant differences in graft survival between transplants with DESAs having high versus low total Ellipro scores. We conclude that Ellipro scores cannot be used to identify DESAs associated with early versus late kidney graft loss in deceased donor transplants.
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