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It is found that the prepared stainless steel is the better shielding substitute to the conventional concretes as well as other standard shielding stainless steel. So, submicron size boron layer used composite materials are more convenient than micron size boron used composite materials as radiation shielding materials for nuclear applications.44Sc is an increasingly investigated positron emitter for use in positron emission tomography (PET) imaging. However, 44Sc is a non-pure positron emitter, since prompt photons are co-emitted during the decay process. This study investigates coincidence energy spectra of 44Sc and its impact on PET quantification on a preclinical and clinical PET system in comparison with 18F. The raw data of the coincidence events revealed characteristic differences comparing the photon energy distribution of 44Sc and 18F. Due to prompt gamma emission of 44Sc, activity recovery is underestimated on PET systems. However, clinical PET imaging of 44Sc with acceptable quantitative accuracy appears feasible by using a single, constant correction factor.

Bronchiolitis obliterans syndrome (BOS) diagnosis in children following allogeneic hematopoietic stem cell transplantation (post-HSCT) is based on detection of airway obstruction on spirometry and air-trapping, small airway thickening or bronchiectasis on chest CT. We assessed the relationship between spirometry indices and low-attenuation lung volume at total lung capacity (TLC) on CT.

Data of children post-HSCT with and without BOS were analyzed. An age-specific, low-attenuation threshold (LAT) was defined as average of (mean-1SD) lung parenchyma attenuation of 5 control subjects without lung disease matched to each age subgroup of post-HSCT patients. % CT lung volume at TLC with attenuation values <LAT was calculated. Association between % lung volume with low attenuation and FEV

/FVC was assessed.

Twenty-nine children post-HSCT were referred to exclude BOS and 12 of them had spirometry and an analyzable chest CT. We studied (i) 6 children post-HSCT/BOS (median age 8.5years [IQR 7, 15]; median FEV

/FVC z-score -2.60 [IQR -2.93, -2.14]); (ii) 6 children post-HSCT/no BOS (age 13.5years [9.8, 16.3]; FEV

/FVC z-score 0.44 [-0.30, 2.10]); and (iii) 40 controls without lung disease (age11years [8.3, 15.8]). Patients post-HSCT/BOS had significantly higher % lung volume with low attenuation than patients post-HSCT/no BOS median % volume 16.4% (7.1%, 37.2%) vs. 0.61% (0.34%, 2.79%), respectively; P=.004. An exponential model described the association between % CT lung volume below LAT and FEV

/FVC z-score (r

=0.76; P<.001).

In children post-HSCT with BOS, low-attenuation lung volume on chest CT is associated with airway obstruction severity as expressed by FEV

/FVC z-score.

In children post-HSCT with BOS, low-attenuation lung volume on chest CT is associated with airway obstruction severity as expressed by FEV1/FVC z-score.The first avian H7N9 influenza outbreak in spring of 2013 emerged in an unprecedented transmission from infected poultry to humans in the Yangtze delta area, eastern China, posing a dual challenge to public health and poultry industry. However, the mechanism for how avian H7N9 influenza virus adapts to mammalian hosts has not been clearly understood. Here, to identify adaptive changes that confer enhanced virulence of H7N9 virus in mammals, we generated a mouse-adapted H7N9 variant virus (S8) by serial lung-to-lung passages of the wild-type SDL124 virus in mice and compared their phenotype in vivo and in vitro. Sequence analysis showed that the two viruses differed by 27 amino acids distributed among six genes, containing changes in PB2 (E627K, D701N) and HA (Q226L) genes. The 50% mouse lethal dose (MLD50) of S8 reduced about 500 folds, to be moderately pathogenic to mice when compared to that of low pathogenic wild-type SDL124. Moreover, S8 replicated efficiently in mouse lungs and displayed expanded tissue tropism, and induced a greater degree of pulmonary edema and higher level of inflammatory cell infiltration in bronchoalveolar lavage fluids than SDL124 did. Interestingly, the mouse adapted S8 virus obtained strong affinity for human-like (SAα-2,6 Gal) receptor during the adaptation in mice. Correspondingly, compared with SDL124 virus, S8 virus showed higher replication efficiency in mammalian cells, whereas lower replication ability in avian cells. Taken together, these findings suggest that these mutations synergistically elevate the ability of H7N9 virus to disseminate to multiple organs and subsequently enhance the virulence of H7N9 virus in mammalian hosts.The viviparous teleost Redtail Splitfin (Xenotoca eiseni) is a live bearing fish that presents a novel freshwater model for investigating the effects of maternally derived micropollutants on vulnerable early developmental life stages. Here, adult female X. eiseni were exposed to 17α-ethinyloestradiol (EE2), a potent contraceptive oestrogen, at environmentally relevant concentrations, to investigate for effects on sex partitioning and development. Pregnant and non-pregnant females were exposed for four weeks to EE2 at measured concentrations of 0.9 and 3.4 ng/L EE2 and offspring from gravid females were kept in clean water for a further four weeks. Only pregnant females were seen to respond to 3.4 ng/L EE2 with an increase in the transcription of hepatic vitellogenins (vtgA, vtgB and vtgC). Offspring of exposed mothers showed no obvious effects on somatic growth, gonadal development, sex partitioning or development. However, there was a higher rate of deformities and developmental abnormalities in offspring of EE2-exposed females. The work presented provides the foundation for the development of X. eiseni as a new freshwater model for studies on maternal transfer of chemical pollutants in live bearing animals.Estrogens and estrogenic endocrine disrupting chemicals can cause gonadal feminization in some vertebrates mainly through estrogen receptor (ER), but the underlying molecular mechanisms are unclear. The present study aimed to identify ER target genes involved in estrogen-caused gonadal feminization in Xenopus laevis. Based on our recent transcriptomic data that 10 nM 17β-estradiol (E2) altered gene transcription in feminizing gonads of male X. Aprotinin laevis at NF stages 48, 50, and 52, we searched estrogen response element (ERE) using the Dragon ERE Finder software in the promoter region of all the E2-regulated genes. As a result, 163 genes containing ERE sequence were identified as predicted ER target genes at NF stage 50 (on the 14th day postfertilization), a crucial stage for gonadal feminization. Then, some of these predicted ER target genes were further investigated, mainly including the genes that were suggested to be involved in E2-caused gonadal feminization and genes being dramatically up or down-regulated by E2. Fifteen genes were demonstrated to be responsive to E2, in turn ER antagonist blocked the E2-regulated transcription. Finally, we identified 10 genes that can bind to ERα by a chromatin immunoprecipitation-qPCR. Taken together, we identified the 10 genes that contain predicted ERE sequences, are responsive to estrogen and ER antagonist, and have ability to bind to ER as ER target genes, including pglyrp2, apoa1, fgb, tdo2, ca6, nags, cpb2, tmprss6, nudc, zwilch. Our results could help to improve the understanding of the molecular mechanisms for gonadal feminization caused by estrogenic endocrine disrupting chemicals in X. laevis, and even in other species.Data, despite being crucial for internal dose assessment, is lacking on the transfer of artificial radionuclides from the environment to the food supply. Expanding the available information on these factors is important for the improvement of dose models for specific scenarios. This paper describes the results of a 70 day field experiment with broiler chickens on the dynamics of excretion of 137Cs and 241Am from the muscle, liver and bone of broilers after a 30 day application of contaminated feed. The radionuclide concentrations in the feed and the thigh muscle, thigh bone and liver of 54 chickens divided between grass meal and soil contaminated feed groups were evaluated by gamma spectrometry for 241Am and 137Cs. The obtained results confirm previous data on the dynamics of the excretion of cesium from organs, which can be described with a fast and a slow exponential curve of excretion. On the 70th day, following the 30-days application, 2-8% of the first-day activity concentrations of 137Cs in organs (muscle, liver, bone) were detected. In the first two days, activity concentration of 241Am decreases twofold in both liver and bone. 35% of the maximum activity concentration of 241Am remained in bone and 15% in liver on the last day of the experiment.Independent Component Analysis (ICA) has attracted chemists recently, for its charm can separate the independent signals from a mixed system and does not need prior knowledge. However, its dissatisfactory performance for the chemical measured signal is still blocking the practicability. Thus, this paper summarized the ICA processing path from the establishment of rectangular coordinates in linear space to the determination of the corresponding relation between the coordinate system and real components. The primary cause of the deviation between the ICA results and the chemical measurements is that the measuring signal was subject to uncertainty. Besides, uncertainty made the deviation of source signal from the statistical independence assumption, or in other words, it appeared to be nonorthogonal. For this key, it proposed to map the measured value to the high-order derivative space, use the derivative to narrow the peak width, reduce the influence of uncertainty, and improve the separation performance of ICA to chemical measurement signal, such as the spectrum. Actual cases of this paper showed that when up to 6th order, the separating results had been perfect for IR spectra, and even for homologs isomers.The characterization of phosphates is generally hampered by the variability of their sources, the complexity of the mineralogical assemblies and/or the thermochemical transformations undergone. Fourier transform infrared (FTIR) spectroscopy can characterize and differentiate phosphates in a practical and efficient way. In this sense, in order to differentiate phosphates from different Amazonian deposits and establish a spectral database, initially small because it is starting, six samples of phosphate rocks were analyzed by FTIR spectroscopy in the near-IR and middle-IR regions using the transmittance, attenuated reflectance, and diffuse reflectance methods. X-ray diffraction and X-ray fluorescence spectroscopy were also used as complementary analyses. The IR results revealed that the transmittance and diffuse reflectance methods are the most suitable for the analysis of phosphate materials, and they should be used together whenever possible. The identification of the PO4 bands, as well as of the (CO3)2-, Al2OH, and NH4 bands, allowed the differentiation of the phosphate materials according to their geological source and the establishment of a database of the studied materials by both the transmittance and diffuse reflectance methods.