Modeling the wavelength dependence of photo-response non-uniformity of a CCD sensor

Precision measurements of astrometry and photometry require stringent control of systematics such as those arising from imperfect correction of sensor effects. In this work, we develop a parametric method to model the wavelength dependence of photo-response non-uniformity (PRNU) for a laser annealed backside-illuminated charge-coupled device. The model accurately reproduces the PRNU patterns of flat-field images taken at nine wavelengths from 290nm to 950nm, leaving the root mean square (RMS) residuals no more than 0.2% in most cases. By removing the large-scale non-uniformity in the flat fields, the RMS residuals are further reduced. This model fitting approach gives more accurate predictions of the PRNU than cubic-spline interpolation does with fewer free parameters. It can be applied to make PRNU corrections for individual objects according to their spectral energy distribution to reduce photometry errors.Comment: 28 pages, 10 figures, comments are welcom

The Age-Redshift Relation For Luminous Red Galaxies Obtained From the Full Spectrum Fitting and Its Cosmological Implications

The relative age of galaxies at different redshifts can be used to infer the Hubble parameter and put constraints on cosmological models. We select 23,883 quiescent luminous red galaxies (LRGs) from the SDSS DR7 and divide them into four sub-samples according to their velocity dispersions and each sub-sample is further divided into 12 redshift bins. The spectra of the LRGs in each redshift and velocity bin are co-added in order to obtain a combined spectrum with relatively high $S/N$. Adopting the GalexEV/SteLib model, we estimate the mean ages of the LRGs from these combined spectra by the full-spectrum fitting method. We check the reliability of the estimated age by using Monte-Carlo simulations and find that the estimates are robust and reliable. Assuming that the LRGs in each sub-sample and each redshift bin were on average formed at the same time, the Hubble parameter at the present time $H_0$ is estimated from the age--redshift relation obtained for each sub-sample, which is compatible with the $H_0$ value measured by other methods. We demonstrate that a systematic bias (up to $\sim 20$) may be introduced to the $H_0$ estimation because of recent star formation in the LRGs due to the later major mergers at z\la 0.4, but this bias may be negligible for those sub-samples with large velocity dispersions. Using the age--redshift relations obtained from the sub-sample with the largest velocity dispersion or the two sub-samples with high velocity dispersions, we find H_0= 65^{+7}_{-3}\kmsmpc or H_0= 74^{+5}_{-4}\kmsmpc by assuming a spatially flat $\Lambda$CDM cosmology. With upcoming surveys, such as the Baryon Oscillation Spectroscopic Survey (BOSS), even larger samples of quiescent massive LRGs may be obtained, and thus the Hubble parameter can be measured with high accuracy through the age--redshift relation.Comment: 13 pages, 7 figures, accepted for publication in AP

The roles of microRNAs in horticultural plant disease resistance

The development of the horticultural industry is largely limited by disease and excessive pesticide application. MicroRNAs constitute a major portion of the transcriptomes of eukaryotes. Various microRNAs have been recognized as important regulators of the expression of genes involved in essential biological processes throughout the whole life cycle of plants. Recently, small RNA sequencing has been applied to study gene regulation in horticultural plants. In this review, we summarize the current understanding of the biogenesis and contributions of microRNAs in horticultural plant disease resistance. These microRNAs may potentially be used as genetic resources for improving disease resistance and for molecular breeding. The challenges in understanding horticultural plant microRNA biology and the possibilities to make better use of these horticultural plant gene resources in the future are discussed in this review

Transfection of IL-10 expression vectors into endothelial cultures attenuates α4β7-dependent lymphocyte adhesion mediated by MAdCAM-1

BACKGROUND: Enhanced expression of MAdCAM-1 (mucosal addressin cell adhesion molecule-1) is associated with the onset and progression of inflammatory bowel disease. The clinical significance of elevated MAdCAM-1 expression is supported by studies showing that immunoneutralization of MAdCAM-1, or its ligands reduce inflammation and mucosal damage in models of colitis. Interleukin-10 (IL-10) is an endogenous anti-inflammatory and immunomodulatory cytokine that has been shown to prevent inflammation and injury in several animal studies, however clinical IL-10 treatment remains insufficient because of difficulties in the route of IL-10 administration and its biological half-life. Here, we examined the ability of introducing an IL-10 expression vector into endothelial cultures to reduce responses to a proinflammatory cytokine, TNF-α METHODS: A human IL-10 expression vector was transfected into high endothelial venular ('HEV') cells (SVEC4-10); we then examined TNF-α induced lymphocyte adhesion to lymphatic endothelial cells and TNF-α induced expression of MAdCAM-1 and compared these responses to control monolayers. RESULTS: Transfection of the IL-10 vector into endothelial cultures significantly reduced TNF-α induced, MAdCAM-1 dependent lymphocyte adhesion (compared to non-transfected cells). IL-10 transfected endothelial cells expressed less than half (46 ± 6.6%) of the MAdCAM-1 induced by TNF-α (set as 100%) in non-transfected (control) cells. CONCLUSION: Our results suggest that gene therapy of the gut microvasculature with IL-10 vectors may be useful in the clinical treatment of IBD

Blockade of neutrophil recruitment to tumor sites based on sialic acid-modified nanoplatforms enhances the efficacy of checkpoint blockade immunotherapy

Checkpoint inhibitors are designed to rejuvenate depleted or suppressed T cells in the tumor microenvironment, relying on the immune system to control and kill tumors. However, accumulating evidence indicates that tumor-infiltrating neutrophils impede the proliferation and activation of T cells and determine the resistance to checkpoint blockade and chemotherapy. In this study, sialic acid ligand-modified colchicine derivative phospholipid complexes specifically targeted tumor-associated neutrophils in the peripheral blood, blocked neutrophil accumulation in tumors, and attenuated the inhibitory effect of infiltrating neutrophils on T cells. Neutrophil blocking therapy enhanced the immunotherapy effect of the PD-L1 antibody in S180 advanced tumors and 4T1 breast cancer. Our study found that PD-L1 antibody monotherapy increased the tumor infiltration of immunosuppressive neutrophils. Combination therapy with neutrophil blocking can greatly reduce tumor-infiltrating neutrophils and increase the proliferation of cytotoxic CD8+ T lymphocytes in the tumor. The combination therapy significantly improved the survival rate of mice with advanced S180 tumors and increased the sensitivity of immune checkpoint inhibitors to 4T1 cold tumors

Retrospective study of risk factors for pericardial effusion after haematopoietic stem cell transplantation in children

ABSTRACTObjectives The clinical characteristics, risk factors and survival prognosis of pericardial effusion (PE) after haematopoietic stem cell transplantation (HSCT) in children were investigated.Methods Clinical data of children who underwent HSCT at the Children's Hospital Affiliated with Chongqing Medical University from January 2016 to December 2022 were analysed retrospectively. Cox proportional hazards regression and the Kaplan-Meier method were used to analyse the risk factors for post-HSCT PE and its impact on outcomes, respectively.Results We enrolled 452 patients with HSCT: 307 males and 145 females, with a median age of 3.4 (1.8 to 6.5) years at transplantation. Forty-five patients (10%) had PE within a median time of 25 (10.5 to 44) days, 42 (93%) within 100 days. Three patients with large PE were treated with pericardiocentesis and drainage, while the others were treated conservatively. Of the 45 patients with PE, 24 survived, and their PE disappeared after treatment. Graft-versus-host disease (GVHD) grade, abnormal pre-HSCT electrocardiogram, hepatic veno-occlusive disease (HVOD), pulmonary infection and Epstein–Barr virus (EBV) infection were risk factors for PE. The overall survival (OS) rates at 1, 3, and 5 years were 86.0%, 84.2%, and 82.3%, respectively. PE had a significant negative effect on OS after HSCT (P < 0.0001). Particularly, one patient with large PE died of pericardial tamponade.Conclusions Post-HSCT PE usually occurred within 100 days. GVHD grade, abnormal pre-HSCT electrocardiogram, HVOD, pulmonary infection and EBV infection were closely related to PE. PE had a significant negative effect on OS rate