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STT-MRAM (Spin-Transfer-Torque Magnetic Random Access Memory) with high-density is considered as one of the most promising storage candidates with potential applications. In the process of MRAM manufacturing, etching step should be stopped precisely at the specific material layer. The dielectric layer should be protected with certain coverage. Then the subsequent etching steps continue. It is crucial to detect the endpoint of the etching during the fabrication process. In the paper, the factors influencing the etching rate are analysed, including gas pressure, gas temperature, ion sheath thickness, self-biased DC voltage and RF power frequency, respectively. An approach based on Response Surface Method (RSM) is adopted to predict the endpoint of the etching process. The optimized interplay relationship is set up among the gas pressure, the gas temperature, the ion sheath thickness, the self-biased DC voltage and the RF power frequency, et al.. It shows that RSM approach is an effective statistical method for the optimization on the etching stop technology, especially when the complex etching condition options are involved. The simulation results demonstrate the MRAM sidewall smoothness can be improved under the optimized etching environment configuration.

Aim. Hyperuricemia (HUA) has received increased attention in the last few decades due to its global prevalence. Our previous study found that administration of a macroporous resin extract of Dendrobium officinale leaves (DoMRE) to rats with HUA that was induced by exposure to potassium oxazine combined with fructose and a high-purine diet led to a significant reduction in serum uric acid (SUA) levels. The aim of this study was to explore the effects of DoMRE on hyperuricemia induced by anthropomorphic unhealthy lifestyle and to elucidate its possible mechanisms of action. Methods. Dosages (5.0 and 10.0 g/kg/day) of DoMRE were administered to rats daily after induction of HUA by anthropomorphic unhealthy lifestyle for 12 weeks. The levels of UA in the serum, urine, and feces; the levels of creatinine (Cr) in the serum and urine; and the levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum were all measured using an automatic biochemical analyzer. The activities of xanthine oxidase (XOD) and adenosine deaminase (ADA) in the serum, liver, and intestine tissue supernatant were measured using appropriate kits for each biological target. The expressions levels of UA transporters (ABCG2 and GLUT9), tight junction (TJ) proteins (ZO-1 and occludin), and inflammatory factors (IL-6, IL-8, and TNF-α) in the intestine were assayed by immunohistochemical (IHC) staining. Hematoxylin and eosin (H&E) staining was used to assess histological changes in the renal and intestinal tissues. Results. DoMRE treatment significantly reduced SUA levels and concomitantly increased fecal UA (FUA) levels and the fractional excretion of UA (FEUA) in HUA rats. Furthermore, DoMRE significantly reduced both the XOD activity in the serum, liver, and intestine and the ADA activity in the liver and intestine. DoMRE also effectively regulated the expression of GLUT9 and ABCG2 in the intestine, and it significantly upregulated the expression of the intestinal TJ proteins ZO-1 and occludin. Therefore, DoMRE reduced the damage to the intestinal barrier function caused by the increased production of inflammatory factors due to HUA to ensure normal intestinal UA excretion. Conclusion. DoMRE demonstrated anti-HUA effects in the HUA rat model induced by an anthropomorphic unhealthy lifestyle, and the molecular mechanism appeared to involve the regulation of urate transport-related transporters (ABCG2 and GLUT9) in the intestine, protection of the intestinal barrier function to promote UA excretion, and inhibition of XOD and ADA activity in the liver and intestine to inhibit UA production in the HUA-induced rats.

Phytopathogenic bacteria are a major cause of crop mortality and yield reduction, especially in field cultivation. The lack of effective chemistry agri-bactericides is responsible for challenging field prevention and treatment, prompting the development of long-lasting solutions to prevent, reduce, or manage some of the most devastating plant diseases facing modern agriculture today and in the future. Therefore, there is an urgent need to find lead drugs preventing and treating phytopathogenic bacterial infection. Drug repurposing, a strategy used to identify novel uses for existing approved drugs outside of their original indication, takes less time and investment than Traditional RD Strategies in the process of drug development. Based on this method, we conduct a screen of 700 chemically diverse and potentially safe drugs against Xanthomonas oryzae PV. oryzae ACCC 11602 (Xoo), Xanthomonas axonopodis PV. citri (Xac), and Pectobacterium atrosepticum ACCC 19901 (Pa). Furthermore, the structure-activity relationship and structural similarity analysis of active drugs classify potent agri-bactericides into 8 lead series: salicylanilides, cationic nitrogen-containing drugs, azole antifungals, N-containing group, hydroxyquinolines, piperazine, kinase inhibitor and miscellaneous groups. MIC values were evaluated as antibacterial activities in this study. Identifying highly active lead compounds from the screening of approved drugs and comparison with the currently applied plant pathogenic bactericide to validate the bactericidal activity of the best candidates and assess if selected molecules or scaffolds lead to develop new antibacterial agents in the future. In conclusion, this study provides a possibility for the development of potent and highly selective agri-bactericides leads.

Based on the density functional theory with hybrid functional approach, we calculated the structural, electronic, and the optical properties of Cu2MgSn(S1-xSex)4 (CMTSSe), an potential photovoltaic material for thin film solar cells. The calculation reveals a phase transition from kesterite to stannite structure when Zn atoms are substituted by Mg atoms. In particular, the S-to-Se ratio can determine the energy splitting between the electronic states at the top of the valence band. The band gaps of CMTSSe can be tuned in the ranges of 1.01-1.58 eV. Calculated optical properties and tunable band gaps make them beneficial for achieving band-gap-graded solar cells.

Objective: To investigate the clinical effect of kunfukang capsule on improving uterine microcirculation in patients with sequelae of pelvic inflammatory disease, and to observe its influence on levels of CRP, GM-CSF and MCP-1 in peripheral blood. Methods: 126 patients with pelvic inflammatory disease sequelae admitted to our hospital from January 2017 to June 2018 were selected and divided into control group and observation group with 63 cases in each group according to the random number table method. Patients in the control group were given azithromycin tablets orally, while patients in the observation group were treated with kunfukang capsule on the basis of control group,7days for a course of treatment, 4 courses of continuous treatment. The purpose of this study was to compare the clinical effects of treatment between the two groups, evaluate the TCM syndrome score, observe the levels of CRP, GM-CSF and MCP-1 in uterine microcirculation and peripheral blood, and record the adverse reactions of patients during treatment. Results: The effective rate of 90.48% in the observation group was significantly higher than that in the control group of 77.78%(P

Tonal noise is an essential characteristic of the noise generated from a forward-curved-blades centrifugal fan. Herein, methods to unevenly arrange blades, in particular, a random modulation method, were studied to weaken the undesired tonal noise and reshape the noise spectrum. First, the balance and aerodynamic performance requirements of the impeller were considered when designing the unevenly spaced blades. The modulated blade positions had to satisfy the dynamic balance condition, while the variation of spacing between every two adjacent blades should not exceed 30% of the original spacing in the even impeller. Next, the influence of non-uniform blades on the noise spectrum characteristics of the fan was theoretically predicted by calculating the interference functions at each discrete frequency. Finally, computational fluid dynamics and computational aeroacoustics analyses were performed to investigate the acoustic performance of each uneven blade spacing scheme. Both the pressure fluctuation on the tongue and the noise frequency spectrum from the acoustic receiver demonstrated that unevenly spaced blades could reduce the tonal noise by dispersing the acoustic energy at the blade passing frequency to other specific frequencies as a form of sidebands. Compared with the existing sinusoidal modulation method, the random modulation method has no limits on the blade number. Moreover, this method has a higher degree of freedom that could overcome all limitations of blade spacing. It is shown that a reasonable blade distribution designed by this method could reduce tonal noise without negatively affecting the aerodynamic performance and the overall noise level.

The type-II InAs/GaSb superlattices (T2SLs)-based 640 × 512 long wavelength infrared (LWIR) Focal Plane Array (FPA) detector with15 μm pitch and 50% cut-off wavelength of 10.5 μm demonstrates a peak quantum efficiency of 38.6% and peak detectivity of 1.65 × 1011 cm Hz1/2 W−1 at 8.1 μm, high pixel operability of 99.5% and low responsivity non-uniformity of 2.69% at 80 K. The FPA exhibits clear infrared imaging at 110 K and diffusion-limited dark current densities below Tennant’s ‘Rule07’ at temperature above 100 K, which is attributed to the efficient suppression of diffusion dark current and surface leak current by introducing M-structure barrier and double hetero-structure passivation layers.

For type-II InAs/GaSb superlattice (T2SL) photodetectors with deep and vertical mesa sidewalls, passivation for suppression of surface leakage currents is facing two key challenges that in the conformal coating of sharp sidewalls and increasing dominance of surface leakage currents as device dimensions shrink. In this work, atomic layer deposited (ALD)-Al2O3 and SiO2 method was employed as conformal passivation for deep and vertical mesa sidewalls. And a stable and high-quality interface between the ALD-Al2O3 and T2SL mesa sidewalls was obtained by the combined pretreatment of trimethylaluminum (TMA) and H2 plasma exposure (Al2O3TH), and thus a significant improvement in electrical performances has been achieved. The electrical performances before and after baking were compared among the Al2O3TH, conventional sulfur plus SiO2 passivated photodiodes. The dark current density of Al2O3TH passivated photodiodes were improved by 81% at 77 K under 0.1 V reverse bias and exhibited no deterioration after 90 °C-4 days baking treatment. Investigation on the effects of TMA and/or H2 plasma pretreatments demonstrates that combined pretreatment of TMA and H2 plasma, rather than TMA or H2 plasma alone, prior to the deposition of ALD-Al2O3 leads to a more thorough elimination of interface native oxides and surface states introduced in mesa process. The innovative application of this effective surface pretreatment technique is very encouraging for the passivation of deep and vertical sidewalls in III-V compound-based devices, such as large-format T2SL infrared detectors.

Novel measurements of the neutron energy spectra of the 9Be(d,n)10B reaction with a thick beryllium target are performed using a fast neutron time-of-flight (TOF) spectrometer for the neutron emission angles and , and the incident deuteron energies are 250 and 300 keV, respectively. The neutron contributions from the 9Be(d,n)10B reaction are distributed relatively independently for the ground state and the first, second, and third excited states of 10B. The branching ratios of the 9Be(d,n)10B reaction for the different excited states of 10B are obtained for the neutron emission angles and , and the incident deuteron energies are 250 and 300 keV, respectively. The branching ratio of the 9Be(d,n)10B reaction for the third excited state decreases with increase in the incident deuteron energy, and the branching ratios for the ground state and the second excited state increase with increase in the neutron emission angle.

An intense D-T/D-D neutron generator is currently being developed at the Lanzhou University. The Cockcroft–Walton accelerator, as a part of the neutron generator, will be used to accelerate and transport the high-current low-energy beam from the duoplasmatron ion source to the rotating target. The design of a high-current low-energy beam transport (LEBT) line and the dynamics simulations of the mixed beam were carried out using the TRACK code. The results illustrate that the designed beam line facilitates smooth transportation of a deuteron beam of 40 mA, and the number of undesired ions can be reduced effectively using two apertures.

An entropy analysis and design optimization methodology is combined with airfoil shape optimization to demonstrate the impact of entropy generation on aerodynamics designs. In the work herein, the entropy generation rate is presented as an extra design objective along with lift-drag ratio, while the lift coefficient is the constraint. Model equation, which calculates the local entropy generation rate in turbulent flows, is derived by extending the Reynolds-averaging of entropy balance equation. The class-shape function transform (CST) parametric method is used to model the airfoil configuration and combine the radial basis functions (RBFs) based mesh deformation technique with flow solver to compute the quantities such as lift-drag ratio and entropy generation at the design condition. From the multi-objective solutions which represent the best trade-offs between the design objectives, one can select a set of airfoil shapes with a low relative energy cost and with improved aerodynamic performance. It can be concluded that the methodology of entropy generation analysis is an effective tool in the aerodynamic optimization design of airfoil shape with the capability of determining the amount of energy cost.

The multi-layer computing model is developed to calculate wide-angle neutron spectra, in the range from 0° to 180° with a 5° step, produced by bombarding a thick beryllium target with deuterons. The double-differential cross-sections (DDCSs) for the 9Be(d, xn) reaction are calculated using the TALYS-1.8 code. They are in agreement with the experimental data, and are much better than the PHITS-JQMD/GEM results at 15° , 30° , 45° and 60° neutron emission angles for deuteron energy of 10.0 MeV. In the TALYS-1.8 code, neutron contributions from direct reactions (break-up, stripping and knock-out reactions) are controlled by adjustable parameters, which describe the basic characteristics of typical direct reactions and control the relative intensity and the position of the ridgy hillock at the tail of DDCSs. It is found that the typical calculated wide-angle neutron spectra for different neutron emission angles and neutron angular distributions agree quite well with the experimental data for 13.5 MeV deuterons. The multi-layer computing model can reproduce the experimental data reasonably well by optimizing the adjustable parameters in the TALYS-1.8 code. Given the good agreement with the experimental data, the multi-layer computing model could provide better predictions of wide-angle neutron energy spectra, neutron angular distributions and neutron yields for the 9Be(d, xn) reaction neutron source.

Cranial radiation therapy can induce cognitive decline. Impairments of hippocampal neurogenesis are thought to be a paramountly important mechanism underlying radiation-induced cognitive dysfunction. In the mature nervous system, DNA double-strand breaks (DSBs) are mainly repaired by non-homologous end-joining (NHEJ) pathways. It has been demonstrated that NHEJ deficiencies are associated with impaired neurogenesis. In our study, rats were randomly divided into five groups to be irradiated by single doses of 0 (control), 0 (anesthesia control), 2, 10, and 20 Gy, respectively. The cognitive function of the irradiated rats was measured by open field, Morris water maze and passive avoidance tests. Real-time PCR was also used to detect the expression level of DNA DSB repair-related genes involved in the NHEJ pathway, such as XRCC4, XRCC5and XRCC6, in the hippocampus. The influence of different radiation doses on cognitive function in rats was investigated. From the results of the behavior tests, we found that rats receiving 20 Gy irradiation revealed poorer learning and memory, while no significant loss of learning and memory existed in rats receiving irradiation from 0–10 Gy. The real-time PCR and Western blot results showed no significant difference in the expression level of DNA repair-related genes between the 10 and 20 Gy groups, which may help to explain the behavioral results, i.e. DNA damage caused by 0–10 Gy exposure was appropriately repaired, however, damage induced by 20 Gy exceeded the body's maximum DSB repair ability. Ionizing radiation-induced cognitive impairments depend on the radiation dose, and more directly on the body's own ability to repair DNA DSBs via the NHEJ pathway.

Two typical red-tide algae, Skeletonema costatum and Prorocentrum donghaiense were selected as studied objects. The nitrate reductase activity (NRA) and the growth of the two algae under different illuminations through incubation experiment were studied. The illumination condition was consistent with in situ. Results showed that P. donghaiense and S. costatum could grow normally in the solar radiation ranged from 30-60 W x m(-2), and the growth curve was "S" type. However, when solar radiation was below 9 W x m(-2), the two alga could hardly grow. In the range of 0-60 W x m(-2), three parameters (NRAmax, micro(max), Bf) increased with the increasing of light intensity, indicating that the light intensity can influence the grow of alga indirectly through influencing the nitrate reductase activity. The micro(max) and NRAmax in unite volume of Skeletonema costatum were higher than those of Prorocentrum donghaiense, indicating that Skeletonema costatum can better utilize the nitrate than Prorocentrum donghaiense.

Based on the data from cruises that carried out in the Yellow Sea and Bohai Sea from April to May, 2010, the horizontal distribution of DOC was studied. And the influencing factors were preliminary discussed. The results showed that the concentration of DOC in the Yellow Sea and Bohai Sea ranged from 0.96 to 4.71 mg x L(-1) in spring and the average content was 2.27 mg x L(-1). In horizontal distribution, the highest DOC content appeared in the coastal zones both in the south and the north and it tended to decrease toward the offshore in central section on the whole. The highest DOC value was in the nearshore in the western of Bohai Sea and eastern of Shandong Peninsula which was mainly affected by the terrestrial inputs and the offshore current, especially in the nearshore of the western of Bohai Sea, the highest DOC content was 4.71 mg x L(-1). The second highest DOC value was in the Northeast of Yangtze River Estuary which was mainly affected by the Yangtze River Diluted Water (YRDW). However, the low DOC content was mainly found in open seas in the central of the South Yellow Sea, and the DOC value was lower than 1.50 mg x L(-1).

To investigate the effect of hydrogen sulfide (H2S) on mitochondrial function in acute myocardial ischemia in rats.Acute myocardial ischemia models were established by ligating the left anterior descending coronary artery (LADC) of rats. Fourty-eight male SD rats were randomly divided into 6 groups (n = 8): sham operation group, ischemia group, ischemia + sodium hydrosulfide (NaHS) low, middle and high dose groups and ischemia + DL-proparglycine(PPG) group. The ultrastructures of myocardial mitochondria were observed with electron microscope. The content of H2S in plasma and the activity of cystathionine-gamma-lyase (CSE) in myocardial tissue of rats were respectively detected. The swelling and activity of myocardial mitochondria were determined. The activities of ATPase, GSH-Px, SOD and the content of malondial-dehyde (MDA) in myocardial mitochondria of rats were also measured.Compared with those of the sham operation group, the content of H2S in plasma, the activity of CSE in myocardial tissue and the activity of myocardium mitochondria were significantly decreased. The activities of ATPase, SOD, GSH-Px in myocardial mitochondria were significantly decreased, The content of malondial dehyde(MDA) in myocardial mitochondria and the swelling of mitochondria were distinctly increased in the ischemia group (P0.01). Compared with those of the ischemia group, the content of H2S in plasma and the activity of CSE in myocardial tissue were increased, and the activities of mitochondria, ATPase, SOD, and GSH-Px in myocardial mitochondria were significantly increased in ischemia + NaHS low, middle and high-dose groups; the swelling of mitochondria and the content of MDA in myocardial mitochondria were significantly decreased in ischemia + NaHS middle and high-dose groups (P0.05 or P0.01). The administration of PPG could partially reduce the myocardial protection of hydrogen sulfide (P0.05 or P0.01).It could be concluded that the administration of hydrogen sulfide could enhance the activities of mitochondrial ATPase, SOD, GSH-Px, decrease the level of mitochondrial lipid peroxidation, and play a protective effect against acute myocardial ischemia.