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In recent years, higher requirements have been placed on the response characteristics of X-ray detectors in the field of medical diagnostic imaging. Due to this, high sensitivity, high attenuation coefficient and low cost detection materials need to be developed. In this paper, the geometric model of a detector was established by Geant4 code. The absorption efficiency and mass attenuation coefficient of MAPbBr3 crystals were calculated in the energy range of 30 keV to 100 keV. Compared with the mass attenuation coefficient of the NIST database, the deviation was within 1.39%. The signal charge number and detection sensitivity of the X-ray interaction with the MAPbBr3 crystal ware calculated. Compared with the CdTe crystal and α-Se, the MAPbBr3 crystal still had a larger detection sensitivity under a smaller applied electric field, which was approximately 9 times higher than that of α-Se. This result indicated that the detection sensitivity could be greatly improved by using a high atomic number and high charge mobility-lifetime product. Based on the simulation results, the 2 mm thick MAPbBr3 crystal exhibited the highest detection sensitivity at 60 keV X-rays, which was in agreement with the experimental results.

This study was conducted to investigate the effects of soybean antigen proteins on serum cytokine levels and claudin-1 distribution in the intestine of weaned piglets. Seventy piglets (24 d of age) were randomly divided into seven groups. Piglets in group A were fed a basal diet, in groups B, C and D were fed the basal diet supplemented with β-conglycinin; and in groups E, F, G were fed the basal diet supplemented with glycinin. Blood samples were collected and analysed for IFN-γ, IL-2, IL-4 and IL-6 levels on day 24, 26, 28 and 30. At the end of the trial, five piglets per group were sacrificed and the small intestine was collected to evaluate intestinal claudin-1 distribution and OD of the relative staining positivity. β-Conglycinin and glycinin decreased the growth performance in piglets by decreasing ADFI, ADG and increasing F/G. Serum levels of IL-2, IL-4 and IL-6 in β-conglycinin and glycinin groups ranged from 126.067 to 144.067 ng • L−1, 31.798 to 44.360 ng • L−1 and 36.360 to 40.482 ng • L−1 on day 24, 26 and 30. However, serum IFN-γ levels were negatively correlated with soybean antigen proteins supplementation levels ranged from 6.956 to 15.361 ng • L−1. The treatment groups had lower OD values of claudin-1 than those of the control group. The β-conglycinin groups had lower distribution and OD values than the glycinin groups at similar antigen protein supplementation levels. These results suggest that β-conglycinin and glycinin damage the intestinal mucosal immune barrier in weaned piglets.

Glycinin, an antigenic glycoprotein found in soybeans, is the major cause of allergic reactions in young animals. The objective of this study was to evaluate the effects of a prior immunisation of sucking piglets with glycinin on their post-weaning growth performance, serum immunoglobulin contents, small intestinal histamine release and mucosal histology. Forty piglets (7 d of age) were randomly divided into four groups of 10 piglets each. Piglets of Group C (Control) received a physiological saline solution, Groups Im (Immunised) and Im + S (Sensitised) were immunised twice with 500 μg/kg of glycinin at 7 and 21-d-old. All piglets were weaned at 23 d; Groups Im + S and S were sensitised with 2500 μg/kg of glycinin at weaning. Compared with Group C, in Group S the average daily gain (ADG), average daily feed intake and gain:feed ratio were decreased, and serum levels of IgG and IgE were increased. Furthermore, in this group, the histamine levels in the duodenum and ileum were significantly decreased, and the structure of duodenal and ileal mucosa was severely damaged. On the contrary, in Groups Im and Im + S the ADG was increased, serum IgE levels were decreased, intestinal histamine levels were increased and the intestinal mucosa was not damaged. These findings suggest that prior immunisation with glycinin can protect the structural integrity of the intestinal mucosal epithelia and alleviate allergic reactions in piglets.

In this experiment, the effects of soybean antigen proteins on intestinal permeability, 5-hydroxytryptamine (5-HT) levels and secretory IgA (sIgA) distribution in the intestine of weaned piglets were evaluated. Thirty piglets (21 d of age) were randomly divided into three groups: control group, glycinin-sensitised group and β-conglycinin-sensitised group. Piglets in the control group were fed a basal diet, and in two sensitised groups were fed the diet with 4% glycinin or β-conglycinin. Piglets in glycinin and β-conglycinin groups were sensitised twice on 21–27 d and 32–34 d period, respectively. Blood samples were collected and analysed for D-lactic acid, diamine oxidase (DAO) and 5-HT levels on d 21, 28 and 35. At the end of the trial, five piglets per group were sacrificed and the small intestine was collected to evaluate intestinal sIgA distribution and the optical density (OD) of the relative staining positivity. The results revealed that the piglets in glycinin and β-conglycinin groups had higher D-lactic acid, DAO and 5-HT levels than those of the control group (p duodenum > proximal jejunum and distal ileum > distal jejunum. These results suggest that soybean antigen proteins induce allergic reactions, damage the intestinal mucosa, increase intestinal permeability and promote sIgA synthesis in weaned piglets.

The article offers information on a study on effect of anions formulas in diet on serum biochemical parameters and reproductive performances of sows. It informs that different groups of hybrid sows were given differed diet plans and the parameters such as birth weight, survival rate and litter size were surveied. The study concluded that D3 diet was optimal while D4 diet was unsuitable for reproductive performances in sows.

A bistable liquid crystal cell with splay and π twist stable states is obtained by doping a chiral additive in a splay cell filled with dual frequency liquid crystals. The switching between the two states is achieved by using a sequential waveform of low and high frequencies. The switching mechanisms are proposed by using the backflow effect together with the anisotropic properties of dual frequency liquid crystals. As a result, the two stable states have the superior memory characteristics due to the topological inequivalence. [ABSTRACT FROM AUTHOR]

Single photon counting using a charge-coupled device (CCD) is a conventional method of measuring the x-ray production of laser plasma. But the spectrum is seriously distorted when measuring a short pulse laser plasma x-ray source. Here we explore this abnormal spectral distortion using a silicon sensor-based CCD (PIXIS-XB: 1300R). We found that the spectral distortion is caused by the continuous spectrum of Compton scattering electrons and the K-α and K-β characteristic lines of Ag elements excited by the harder x-rays of >25 keV. We calibrated the detection efficiency of the incident x-ray, the excitation efficiency of the Ag characteristic lines and the Compton scattering electrons spectrum in the x-ray energy range from 20 keV to 100 keV. We also improve the algorithm of spectrum reconstruction to loosen the exposure level limit markedly. Our effort extends the detecting range of silicon sensor-based CCDs from 0.5–30 keV to 0.5–80 keV. The present analysis can also be used in the spectral extraction of GaAs and CdTe high-Z sensor-based CCDs. [ABSTRACT FROM AUTHOR]

In order to generate an antibody against a small hapten molecule, the hapten is cross-linked with carrier protein to make it immunogenic. In this study, the hapten (ochratoxin A, OTA) was coupled to ovalbumin (OVA) by an active ester reaction. To develop a technique for detecting the conjugation, the hapten-protein conjugate (OTA-OVA) was characterized thoroughly by immunoarray technology, ultraviolet (UV) spectroscopy and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), respectively. The molecular weight of OTA-OVA was 50 350.141 Da, and the molecular weight of OVA was 44 887.506 Da, which were determined by MALDI-TOF-MS, respectively. In OTA-OVA, the molecular coupling ratio was 13:1 by MALDI-TOF-MS while the molecular coupling ratio was 10:1 by UV. In this experiment, UV and MALDI-TOF-MS were selected as the efficient methods to evaluate the cross-linking effect and calculate the molecular coupling ratio.