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Introduction Space radiation can influence the health of astronauts, and neutron radiation plays a crucial role. We researched the effect of neutron on visual organs of rats, and hope to find the possible mechanism. Materials and methods We irradiated rats with neutrons. Optical coherence tomography (OCT) and fundus photography (FP) were used to study the morphological changes of visual organs in living rats. Electroretinogram (ERG) and visual evoked potential (VEP) were measured to research the changes in visual function. ITRAO/TMT labeling and high PH reverse separation were used to identify and quantify the differentially expressed proteins (DEPs) in the retina to explore the mechanisms. Protein-protein interaction (PPI) networks were used to screen the key proteins closely related to neutron-induced retinal damage. Results Irradiated rats developed posterior vitreous detachment (PVD). The vessel density of retina increased. The amplitude of b-wave of dark adaptation ERG was increased, which suggested that bipolar cells and Muller cells in retina might be abnormal. The latency of N2-wave of VEP was prolonged, which suggested that combined with the results of nuclear magnetic resonance (NMR)，the the intracranial pressure (ICP) of rats may be increased. Aquaporin-1, vinculin, Tropomyosin-1 and Myosin light chain kinase may be closely related to the retinal damage by neutron. Conclusion The morphology and function of visual organs are affected by neutrons. The ERG and VEP analysis would be likely to provide reference for non-destructive detection of retinal damage to astronauts in orbit.

Our studies showed that the living irradiated Saccharomyces cerevisiae has a good biosorption capacity for strontium and high tolerance to irradiation, but the mechanisms of this bioaccumulation ar...

In this work, magnetic yeast (MY) was produced through an in situ one-step method. Then, MY was used as the core and the antibiotic sulfamethoxazole (SMX) as the template to produce highly selective magnetic yeast-molecularly imprinted polymers (MY@MIPs). The physicochemical properties of MY@MIPs were assessed by Fourier-transform infrared spectroscopy (FT-IR), a vibrating sample magnetometer (VSM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), specific surface area (SBET) determination, and scanning electron microscopy (SEM). Batch adsorption experiments were carried out to compare MY@MIPs with MY and MY@NIPs (magnetic yeast-molecularly imprinted polymers without template), with MY@MIPs showing a better performance in the removal of SMX from water. Adsorption of SMX onto MY@MIPs was described by the pseudo-second-order kinetic model and the Langmuir isotherm, with maximum adsorption capacities of 77 and 24 mg g−1 from ultrapure and wastewater, respectively. Furthermore, MY@MIPs displayed a highly selective adsorption toward SMX in the presence of other pharmaceuticals, namely diclofenac (DCF) and carbamazepine (CBZ). Finally, regeneration experiments showed that SMX adsorption decreased 21 and 34% after the first and second regeneration cycles, respectively. This work demonstrates that MY@MIPs are promising sorbent materials for the selective removal of SMX from wastewater., This work is a contribution to the research project WasteMAC (POCI-01-0145-FEDER-028598) funded by FCT – Fundação para a Ciência e a Tecnologia, I.P., through national funds, and the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020. Thanks are due to FCT/ Ministério da Ciência, Tecnologia e Ensino Superior (MCTES), for the financial support to CESAM (UIDP/50017/2020+UIDB/50017/2020), through national funds. The work was also sponsored by the Natural Science Foundation of Jiangsu Province (SBK201404182); the environmental protection scientific research subject in Jiangsu province (Grant NO.2016003); and the A Project Fund by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD). Marta Otero and Vânia Calisto are thankful to FCT for the Investigator Program (IF/00314/2015) and for the Scientific Employment Stimulus (CEECIND/00007/2017), respectively. Guilaine Jaria thanks for her FCT PhD grant (SFRH/BD/138388/2018) supported by the National Funds and FSE, POCH (Programa Operacional Capital Humano), and the European Union. María V. Gil acknowledges support from a Ramón y Cajal grant (RYC-2017-21937) of the Spanish Government, co-financed by the European Social Fund (ESF).

We describe synthesis of high-quality crystalline ZnO thin films via hydrothermal solution method at low temperature. A variety of ZnO material structures (nanowires, nanorods , and thin films) have been obtained with various Cu(NO 3)2 concentrations of the precursor solution. Interdigitated finger metal-semiconductor-metal structure UV photodetector with gold Schottky contact is fabricated based on the ZnO materials, which has been employed to investigate the UV photo detection performance. Our results indicate that the performance of the device depends on the structure of the ZnO materials. With Cu(NO 3)2 concentration of 0.25 mM, the photodetector with the lowest dark current of 1.88 nA, responsivity of 1.46A/W, and UV-to-Visible rejection ratio up to four orders at 1 V bias has been achieved.

In this study, the Saccharomyces cerevisiae (S. cerevisiae) was modified by γ-ray. The RNA-seq results reflect that the high γ-ray energies could change some gene fragments, such as deletion, recombination, and mutation. The biosorption of strontium ions (Sr2+) to different types of S. cerevisiae (S. cerevisiae (K-0), modified S. cerevisiae (Y-7), and non-living S. cerevisiae (H-K)) from the simulated high-level liquid waste (S-HLLW) was assessed at different experimental conditions. The sorption experimental results show that, under an appropriate condition, γ-ray radiation can enhance its biosorption capacity slightly of Sr2+ to S. cerevisiae. The maximum metal uptake and efficiency of Y-7 under S-HLLW were 11.656 mg g−1 and 37.91% at 32 h (wet weight), respectively. They decreased to 9.46 mg g−1 and 30.76% under radiation conditions. SEM-EDX and TEM analysis indicates that Sr2+ was adsorbed both on the cellular surface and the inner parts of the cells. Our experimental results fit well to the Langmuir and Freundlich model isotherms (r2 > 0.94), and the maximum biosorption capacity values reached qmax > 24.74 mg g−1 at 32 °C. Negative values of ΔG0 and positive values of ΔH0 were observed, indicating the spontaneous and endothermic nature of Sr2+ biosorption on modified S. cerevisiae. The biosorption kinetics follow a pseudo-second-order equation at 32 °C (r2 > 0.94). The desorption efficiency of Sr2+ adsorbed onto Y-7 was 7.65 ± 0.52%, 76.51 ± 2.13%, and 65.62 ± 2.42% by deionized water, 1 M HCl, and 0.1 M EDTA-Na, respectively. However, they were lower than H-K (18.82, 83.32, and 73.32%). Our findings demonstrate that living S. cerevisiae (Y-7) is a promising sorbent material for the treatment of radioactive process streams.

In this paper, we propose a new linear second-order finite difference scheme for Allen–Cahn equations. We use a modified Leap-Frog finite difference scheme with stabilized term and a central finite difference scheme for temporal and spatial discretization respectively. It is shown that the discrete maximum principle holds under reasonable constraints on time step size and coefficient of stabilized term. Based on the maximum stability, the maximum-norm error is analyzed. Moreover, we can see that the proposed scheme is unconditionally energy-stable. Finally, a numerical experiment is performed to verify the theoretical results.

Adsorption behavior and mechanism of Sr(II) and Cs(I) in single and binary solutions using irradiated Saccharomyces cerevisiae was investigated. The effects of several environmental factors on Sr(II) and Cs(I) adsorption to irradiated Saccharomyces cerevisiae was determined. The equilibrium experimental data were simulated by different kinetic models and isotherm models. The combined effect of Sr(II) and Cs(I) on Saccharomyces cerevisiae is generally antagonistic. SEM and EDS analyses indicate that crystals formed on the cell surface are precipitate of Sr(II) and Cs(I), respectively.

As a new-emerging method for strontium disposal, biosorption has shown advantages such as high sorption capacity; low cost. In this study, we investigated the potential of Saccharomyces cerevisiae (S. cerevisiae) in strontium disposal under culture conditions and the effects of irradiation on their biosorption capabilities. We found that S. cerevisiae can survive irradiation and grow. Pre-exposure to irradiation rendered S. cerevisiae resistant to further irradiation. Surprisingly, the pre-exposure to irradiation can increase the biosorption capability of S. cerevisiae. We further investigated the factors that influenced the biosorption efficiency, which were (strongest to weakest): pH > strontium concentration > time > temperature. In our orthogonal experiment, the optimal conditions for strontium biosorption by irradiated S. cerevisiae were: pH 7, 150 mg L-1 strontium at the temperature of 32 °C with 30 h. The equilibrium of strontium biosorption was analyzed by Langmuir and Freundlich models, from which the formal model is found to provide a better fit for the experimental results. The kinetics of strontium biosorption by living irradiated S. cerevisiae was found to be comprised of three phases: dramatically increased during 0-9 h, decreased during 12-24 h, and increased during 30-50 h. These results provide a systematic understanding of the biosorption capabilities of irradiated S. cerevisiae, which can contribute to the development of remediating nuclear waste water.

The objective of this work was to explore the mechanisms participating in strontium sorption by living Saccharomyces cerevisiae (S. cerevisiae). The location of strontium adsorbed by S. cerevisiae was studied by our plasmolysis treatment. The contribution of physical and chemical mechanisms was determined quantitatively by desorption and blockage of functional groups. Moreover, our results indicated that bioaccumulation also played a major role in biosorption by living cells. Thus, supplementary methods including 2-DE (two-dimensional electrophoresis) and Matrix-Assisted Laser Desorption/Ionization Tandem Time of Flight Mass Spectrometry (MALDI-TOF-TOF) were employed to analyze the different proteins. The subsequent desorption % of Sr2+ by Distilled Water (DW), NH4NO3 and EDTA-Na2 from Sr2+ loaded sorbents indicated a minor role for physical adsorption, while ion exchange and complexation were responsible for approximately 20% and 40%. Specific blockage of functional groups revealed that carboxyl and amine groups played an important role in Sr2+ binding to the living S. cerevisiae. From our MALDI-TOF-TOF results, we concluded that 38 proteins showed up-regulated expression profiles and 11 proteins showed down-regulated after biosorption. Moreover, proteins belong to: phagocytic function (Act1p); ion channel (S-adenosylmethionine synthase); glycolysis (Tubulin) may directly involve in strontium bioaccumulation. In conclusion, the present work indicates that the strontium sorption mechanism by living S. cerevisiae is complicated including ion-exchange along with complexation as the main mechanism, whereas the other mechanisms such as physical adsorption play a minor contribution. Metabolically-dependent proteins may play an important role in bioaccumulation.