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During the last several years, the HL-2A experiment has made significant progress in the following areas: (1) lower-hybrid wave (LHW) heating and current drive, (2) plasma confinement and turbulent transport, (3) magnetohydrodynamic (MHD) instabilities and energetic particle physics and (4) H-mode and edge localized mode (ELM) control. The results show that the LHW system working in the co-current mode can reach higher driving efficiency and full non-inductive lower-hybrid current drive (LHCD) has been achieved. The intrinsic poloidal torque characterized by the divergence of the residual stress is deduced from synthesis for the first time. The dynamics of spectral symmetry breaking in drift wave turbulence is in good agreement with the development of the poloidal torque to drive the edge poloidal flow. The influence of the cross-phase dynamics on turbulent stress was also investigated. The ion internal transport barrier has been observed in the NBI-heated plasma, and inside the barrier the ion thermal transport is reduced to the neoclassical level. Besides, micro-turbulence is modulated by the rotation frequency of the magnetic island, and this modulation effect is related to a critical island width. Strong E × B shear is found at the island boundary. Three kinds of axisymmetric modes, beta-induced Alfven eigenmode (BAE), toroidal Alfven eigenmode (TAE) and the ellipticity-induced Alfven eigenmode (EAE), are found to be driven unstable by nonlinear mode coupling between Alfven eigenmodes and tearing mode which is well explained by the nonlinear gyrokinetic theory. The fishbone and tearing modes were actively controlled by the electron cyclotron resonance heating (ECRH). The dynamics of the edge plasma flows and turbulence during the L–I–H transition have been dedicatedly investigated. The geodesic acoustic mode (GAM) and limit cycle oscillation (LCO) coexist for a short time and disappear in the H-mode plasma with the increasing of E × B shear flow before the I–H transition, which plays an important role in the turbulence suppression. Different techniques, such as LHW, ECRH, resonant magnetic perturbation (RMP), and impurity seeding by the laser blow-off (LBO) and supersonic molecular beam injection (SMBI), have been successfully applied to control the large ELMs. It has been found that pedestal turbulence enhancement might be responsible for the observed mitigation effect.

Mitigation of Edge localized mode(ELM) has been achieved with different external actuators such as lower hybrid wave (LHW), mixture supersonic molecular beam injection(SMBI), and laser blow-off(LBO) impurity seeding on HL-2A. During these experiments, the pedestal turbulence enhancement is commonly observed, which is found closely related to ELM mitigation. The turbulence enhancement is caused by the externally driven the velocity shear rate without change of the turbulence correlation length, but correlated to its radial wavenumber spectral shift. A common plausible mechanism for the ELM mitigation with different external source input seems to be involved. A modified theoretical model based on the turbulence radial wavenumber spectral shift is used and successfully interprets the experimental observations. The simulation suggests that a critical growth rate of the most unstable mode, also identified by the experimental results, survives in the competition of the velocity shear rate, enhancing the turbulence intensity. An example of the LHW case is used and good agreements have been found between the experimental results and simulation results.

On the Sun,jets in light bridges are frequently observed with high-resolution instruments.The respective roles played by convection and the magnetic field in triggering such jets are not yet clear.We report a small fan-shaped jet along a LB observed by the 1.6m Goode Solar Telescope(GST) with the TiO Broadband Filter Imager(BFI),the Visible Imaging Spectrometer(VIS) in H{\alpha},and the Near-InfraRed Imaging Spectropolarimeter(NIRIS),along with the Stokes parameters.The high spatial and temporal resolution of those instruments allowed us to analyze the features identified during the jet event.By constructing the H{\alpha} Dopplergrams,we found that the plasma is first moving upward,whereas during the second phase of the jet,the plasma is flowing back.Working with time slice diagrams,we investigated the propagation-projected speed of the fan and its bright base.The fan-shaped jet developed within a few minutes,with diverging beams. At its base,a bright point was slipping along the LB and ultimately invaded the umbra of the sunspot.The H{\alpha} profiles of the bright points enhanced the intensity in the wings, similarly to the case of Ellerman bombs.Co-temporally,the extreme ultraviolet brightenings developed at the front of the dark material jet and moved at the same speed as the fan, leading us to propose that the fan-shaped jet material compressed and heated the ambient plasma at its extremities in the corona.Our multi-wavelength analysis indicates that the fan-shaped jet could result from magnetic reconnection across the highly diverging field low in the chromosphere,leading to an apparent slipping motion of the jet material along the LB.However,we did not find any opposite magnetic polarity at the jet base,as would typically be expected in such a configuration.We therefore discuss other plausible physical mechanisms,based on waves and convection, that may have triggered the event., Comment: 10 pages, 7 figures

Magnetography using magnetic sensitive lines is regarded traditionally as the main instrument for measuring the magnetic field of the whole Sun. Full polarized Stockes parameters ($I$, $Q$, $U$, $V$) observed can be used to deduce the magnetic field under specific theoretical model or inversion algorithms. Due to various reasons, there are often cross-talk effects among Stokes signals observed directly by magnetographs. Especially, the circular polarized signal $V$ usually affects the linear polarized ones $Q$ and $U$ seriously, which is one of the main errors of the value of the transverse magnetic field (parallel to the solar surface) that is related to $Q$ and $U$. The full-disk magnetograph onboard the Advanced Space based Solar Observatory (ASO-S/FMG) is designed to observe Stockes parameters to deduce the vector magnetic field. In this paper, the methods correcting the effects of cross-talk $V$ to $Q$ and $U$ are based on the assumption of perfectly symmetric Q and U and anti-symmetric Stokes V profiles and a new method to reduce the crosstalk effect under observation mode of FMG is developed. Through the test, it is found that the two methods have better effect in cross-talk removal in the sunspot region, and have better consistency. Addtionally, the developed methodcan be applied to remove the cross-talk effect using only one group of $Q$, $U$ and $V$ images observed at one wavelength position., 27 pages, 15 figures, accepted by SolPhys. 2021

A series of novel porphyrin ligands and their zinc complexes with twelve long flexible chains have been synthesized and characterized by UV-Vis, IR, and 1H NMR spectra. Liquid-crystal properties of the compounds are studied by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Absorption spectra, luminescence spectra and fluorescence lifetime of the products are determined.

Cadmium (Cd) is highly toxic to plants, animals, and humans. Limited information is available on the role of nitric oxide (NO) and/or 24-epibrassinolide (EBR) in response of plants to Cd stress. In this study, a hydroponic experiment was performed to investigate the effects of NO and/or EBR on peanut plants subjected to Cd stress (200 µmol L−1) with sodium nitroprusside (SNP, an exogenous NO donor) (250 µmol L−1) and/or EBR (0.1 µmol L−1) addition. The results showed that Cd exposure inhibited plant growth, and this stress was alleviated by exogenous NO or EBR, and especially the combination of the two. Treatment with Cd inhibited the growth of peanut seedlings, decreased chlorophyll content, and significantly increased the Cd concentration in plants. Furthermore, the concentration of reactive oxygen species (ROS) markedly increased in peanut seedlings under Cd stress, resulting in the accumulation of malondialdehyde (MDA) and proline in leaves and roots. Under Cd stress, applications of SNP, EBR, and especially the two in combination significantly reduced the translocation of Cd from roots to leaves, increased the chlorophyll content, decreased the concentrations of ROS, MDA, and proline, and significantly enhanced the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in peanut seedlings. Exogenous NO and/or EBR also stimulated the activities of nitrate reductase (NR) and nitric oxide synthase (NOS) and increased the contents of antioxidants, such as ascorbic acid (AsA) and reduced glutathione (GSH). Furthermore, exogenous NO and/or EBR enhanced Cd accumulation in the cell wall and thus decreased Cd distribution in the organelles in the roots. The concentrations of calcium (Ca), iron (Fe), magnesium (Mg), and zinc (Zn) were also regulated by exogenous NO or EBR, and especially by the two in combination. These results indicated that SNP and EBR, alone and particularly in combination, can mitigate the negative effects of Cd stress in peanut plants.

A 4MW/3.7GHz/3s LHCD system will be developed on HL-2M tokamak. Up to now, half of the system has been constructed, including a 4MW full active multijunction (FAM) concept antenna. The antenna consisted of 6×32 grills. 1-3 power divider in poloidal direction based on TE10-TE30 mode converter is used for 6-row realization. The peak refractive index is designed as n||0=2.25, with high directivity D=0.75 and low reflection coefficient RC

This paper presents recent Lower Hybrid Current Drive (LHCD) progress in SWIP, including the experiments on HL-2A and system development on HL-2M. The 3.7GHz LHCD system was built on HL-2A, where the first Lower Hybrid Wave (LHW) coupling to H-mode plasma experiment via Passive-Active Multijunction (PAM) launcher was carried out. The coupled power has been increased much from 470kW to 1400kW since 2014. The LHW power became more and more important in the H-mode discharges on HL-2A in the past 4 years. In 2018, 1.1s ELMy H-mode was achieved with the help of Neutral Beam Injection (NBI) and LHW injection. However, The LHCD experiments showed distinct characteristic on HL-2A, i.e. no full non-inductive current drive (loop voltage never dropped below 0.3V) and counter-current drive effect found in the situation of co-current drive spectrum. Full non-inductive current drive was finally obtained after the spectrum turned opposite. Besides those achievements, the abnormal LHCD phenomenon discussion, full non-inductive current drive experiments, co-current and counter-current comparison, LHW deposition and mechanism of LHCD ELM mitigation are described. At the same time, a 4MW LHCD system is planned to be constructed on HL-2M. A 2MW LHCD system has been developed for HL-2M tokamak until now. Four TH2103C1 klystrons, transmission lines and a 4MW FAM antenna are included in this system. The other part will be built soon.

A pillbox-type radio-frequency window for lower-hybrid current drive power transmission of 3.7 GHz for 200 kW/2 s is designed. The relative permittivity and the loss tangent of several domestic materials—alumina, boron nitride, and sapphire—are exactly compared by the rectangular cavity perturbation method, and finally, the sapphire is chosen as the window medium. The reflection coefficient of the optimized window can reach 55−dB at 3.7 GHz simulated by high-frequency simulation software, and the peak temperature rise can be limited at 20°C with maximum thermal stress of 1.7 MPa by thermal and mechanical analysis. In the high-power test, 221 kW/3 s energy passes the welded window.

重症急性胰腺炎具有高病死率、高并发症率的特点。通过对急性胰腺炎严重程度的预测，有助于早期识别可能发展为重症胰腺炎的患者，在此基础上及时转诊和干预，从而改善预后、降低费用。目前关于急性胰腺炎的预后指标包括急性生理与慢性健康评分Ⅱ（APACHE Ⅱ）、Ranson评分、胰腺炎活动度评分系统（PASS）、日本严重度评分（JSS）、Glasgow评分等多因素评分系统，以及髓系细胞触发受体-1（TREM-1）、降钙素原（PCT）、C反应蛋白（CRP）、血尿素氮（BUN）、血清肌酐（SCr）等单因素预后指标。本讲座将介绍各类预后指标的适用范围和优缺点，从而为临床应用提供参考。.

Energetic electrons driving low-frequency magnetohydrodynamic instabilities, e.g., electron fishbone (eFB) modes and electron beta-induced Alfvén eigenmodes (eBAEs), are found in co- and counter-current drive low hybrid current drive (LHCD) plasma in HL-2A, respectively. The eBAEs are found in LHCD plasma for the first time. Two branches eFB modes are observed in the core of plasma, and they can transit from the high-frequency one to the low-frequency one continuously. The different mode structures and positions are obtained by tomography of soft x-ray arrays. The frequency jump phenomena of eFB modes are also found. Two eBAEs, with poloidal and toroidal mode numbers m/n = 3/1 and 5/2, are found in the edge of the plasma. The single m/n = 3/1 mode is found when the LHCD power (P LHCD) is 0.44 MW. The strong m/n = 5/2 mode coexists with the weak 3/1 mode when P LHCD = 0.52 MW. Although the current drive direction of LHCD is opposite to the plasma current, the two eBAEs also propagate in the electron diamagnetic drift direction poloidally, which is the same direction as the eFB modes in co-current drive LHCD plasma. With increasing P LHCD (or changed current profile), the value of the edge safety factor (q) decreases. The evolutions of the mode numbers of eBAEs may be related to changes in the edge q factors.

Soil loss tolerance (T value) is one of the criteria in determining the necessity of erosion control measures and ecological restoration strategy. However, the validity of this criterion in subtropical karst regions is strongly disputed. In this study, T value is calculated based on soil formation rate by using a digital distribution map of carbonate rock assemblage types. Results indicated a spatial heterogeneity and diversity in soil loss tolerance. Instead of only one criterion, a minimum of three criteria should be considered when investigating the carbonate areas of southern China because the one region, one T value concept may not be applicable to this region. T value is proportionate to the amount of argillaceous material, which determines the surface soil thickness of the formations in homogenous carbonate rock areas. Homogenous carbonate rock, carbonate rock intercalated with clastic rock areas and carbonate/clastic rock alternation areas have T values of 20, 50 and 100 t/(km2 a), and they are extremely, severely and moderately sensitive to soil erosion. Karst rocky desertification (KRD) is defined as extreme soil erosion and reflects the risks of erosion. Thus, the relationship between T value and erosion risk is determined using KRD as a parameter. The existence of KRD land is unrelated to the T value, although this parameter indicates erosion sensitivity. Erosion risk is strongly dependent on the relationship between real soil loss (RL) and T value rather than on either erosion intensity or the T value itself. If RL > > T, then the erosion risk is high despite of a low RL. Conversely, if T > > RL, then the soil is safe although RL is high. Overall, these findings may clarify the heterogeneity of T value and its effect on erosion risk in a karst environment.

The effects of sodium nitroprusside (SNP, a donor of NO) on cadmium (Cd) toxicity in ryegrass seedlings (Lolium perenne L.) were studied. 100 and 150 μM Cd stress had a detrimental effect on ryegrass seedlings. Exposure of 100 and 150 μM Cd inhibited plant growth, decreased chlorophyll concentration, and reduced the absorption of Fe, Cu and Zn. Excess Cd also altered the activities of antioxidant enzymes, and increased the accumulation of reactive oxygen species (ROS). Exogenous NO alleviated Cd toxicity of ryegrass plants, especially under the stress of 150 μM Cd, as evidenced by improved plant growth and increased concentrations of chlorophyll and mineral nutrients. Exogenous NO also mitigated oxidative stress by regulating the activities of antioxidant enzymes and the contents of non-antioxidants. Moreover, the absorption of Fe, Cu and Zn was increased, indicating that exogenous NO stimulated H+-ATPase activity to promote sequestration or uptake of ions. The applications of NO also reduced the translocation of Cd from roots to the leaves. These results indicate that the mechanisms of NO for mitigating Cd toxicity may be associated with reduced root-to-shoot translocation of Cd and enhanced capacity of antioxidative systems to protect plants from oxidative stress.

We isolated the Arabidopsis drought-resistant mutant csm1-1 and cloned the CSM1 gene (previously called RCI3) which encodes a kind of peroxidase. In this study, we showed that the mutant csm1-1 was more tolerant to selenium (Se) stress than the wild-type, and that the mutant csm1-1 accumulated similar Se content compared with the wild-type when subjected to Se stress. Further analysis revealed that the Se resistance of mutant csm1-1 was associated, at least in part, with the enhanced activities of antioxidant enzymes GSH-POD (glutathione peroxidase) and POD (peroxidase). In addition, enhanced Se resistance of the mutant csm1-1 was partially GSH dependent, which was related to the higher expression level of GSH1 gene involved in GSH synthesis and consequently increased GSH content.

The electrical conductivity of brine-saturated rock is predominantly dependent on the geometry and topology of the pore space. When a resistive second phase (e.g., air in the vadose zone and oil/gas in hydrocarbon reservoirs) displaces the brine, the geometry and topology of the pore space occupied by the electrically conductive phase are changed. We investigated the effect of these changes on the electrical conductivity of rock partially saturated with brine. We simulated drainage and imbibition as invasion and bond percolation processes, respectively, in pipe networks assumed to be perfectly water-wet. The simulations included the formation of a water film in the pipes invaded by the nonwetting fluid. During simulated drainage/imbibition, we measured the changes in resistivity index as well as a number of relevant microstructural parameters describing the portion of the pore space saturated with water. Except Euler topological number, all quantities considered here showed a significant level of “universality,” i.e., insensitivity to the type of lattice used (simple cubic, body-centered cubic, or face-centered cubic). Hence, the coordination number of the pore network appears to be a more effective measure of connectivity than Euler number. In general, the simulated resistivity index did not obey Archie's simple power law. In log-log scale, the resistivity index curves displayed a substantial downward or upward curvature depending on the presence or absence of a water film. Our network simulations compared relatively well with experimental data sets, which were obtained using experimental conditions and procedures consistent with the simulations. Finally, we verified that the connectivity/heterogeneity model proposed by Bernabe et al. (2011) could be extended to the partial brine saturation case when water films were not present.

The effects of sodium nitroprusside (SNP, a donor of NO) on cadmium (Cd) and copper (Cu) toxicity in ryegrass seedlings (Lolium perenne L.) on plant growth, chlorophyll content, the accumulation of superoxide anion (O 2 ·− ), lipid peroxidation, and the activities of antioxidant enzymes were studied. Cd, Cu, and especially Cd+Cu caused serious chlorosis, inhibited the growth of ryegrass seedlings, and increased dramatically the accumulation of Cd and/or Cu in both shoots and roots. However, the addition of 100 μM SNP alleviated significantly the toxic effects induced by Cd or Cu, and especially by Cd+Cu, which was manifested in the increased plant growth, chlorophyll content, and the activation of antioxidant enzymes. Moreover, exogenous NO improved effectively the absorption of mineral elements. In addition, exogenous NO diminished markedly the accumulation of reactive oxygen species (ROS), malondialdehyde (MDA), and proline, but increased the content of ascorbic acid (AsA) and inhibited the translocation of Cd and Cu from roots to shoots. These data also suggested that the alleviating effect of NO may be better when the metal stresses are more serious. NO might act as one of the potential antioxidants to improve plant resistance to the Cd and/or Cu stress.

The interactive effects of salicylic acid (SA) and nitric oxide (NO) on alleviating cadmium (Cd) toxicity in peanut (Arachis hypogaea L.) were studied. Seedlings of two cultivars (Huayu 22 — a big seed type, and Xiaobaisha — a small seed type) were treated with 200 μM CdCl2 without or with 0.1 mM SA or 0.25 mM sodium nitroprusside (SNP, an NO donor). Results show that the Cd exposure depressed the plant growth of both the cultivars but more of Huayu 22 than of Xiaobaisha. Exogenous SA and NO alleviated Cd toxicity in both the peanut cultivars: they improved growth, chlorophyll content, photosynthesis, and mineral nutrition. Furthermore, exogenous SA or NO decreased oxidative stress by increasing activities of antioxidant enzymes and content of non-enzymatic antioxidants. Besides, in roots and leaves of both the cultivars, exogenous SA and NO increased Cd accumulation in the cell wall and decreased Cd distribution to organelles. In particular, the effect of SA+SNP was most obvious.

A 2 MW-3.7 GHz lower hybrid current drive (LHCD) system is under development for physics experiments on the HL-2A device. The RF Power is generated by four TH2103A klystron amplifiers and propagates in the TE10 mode through WR284 waveguides. The transmission lines with a length of 20 m to 30 m are pressurized with 2 bars of nitrogen to decrease the possibility of arcing. The launcher, based on the passive-active multi-junction (PAM) concept, has been developed and is currently being realized. It was designed for a power spectrum peaked at N|| = 2.75 with good coupling properties over a wide range of plasma parameters. The four klystrons are fed by a high-voltage power supply (HVPS) based on the pulse step modulation (PSM) concept with a fast switch-off time of less than ten μs. This system is expected to be in operation within 1 years and will explore many international thermonuclear experimental reactor (ITER) related LH experiments in the following years.

Physics related to fast electrons in lower hybrid (LH) current drive (LHCD) plasma is a very important issue, since these particles will play an important role in runaway electron (RE) generation and lower hybrid wave (LHW)-related physics. Utilizing a new hard X-ray (HXR) pinhole camera, recent HL-2A tokamak experiments have devoted to enhancing the understanding of the physics on fast electrons and LHW. The fast electron bremsstrahlung (FEB) emission in the HXR energy range between 20 and 200 keV was measured by the HXR camera. To study the conversion of LHW-produced fast electrons into REs, a very short pulse of LHW, so-called “blip”, with duration of 5 ms was injected into the plasma during the current flattop phase. A strong enhancement of REs was induced by the blip injection. Measurements from the HXR camera show that the fast electrons generated by LHWs is mainly concentrated in 40-60 keV, which is well consistent with the calculated value based on Landau damping theory. The energy of these seed electrons is higher than the critical runaway energy. This phenomenon may be come from the synergetic effects of Dreicer and avalanche RE generation. Moreover, the measurements indicate that the spatial distribution of the fast electrons during LHCD has a peaked profile, implying that the fast electrons are mainly produced in the plasma core. It also suggests that the energy of the LHW mainly deposited in the plasma core region.

The study aimed to test the effects of sodium nitroprusside [SNP, a nitric oxide (NO) donor], supplied with different approaches on cadmium (Cd) toxicity in lettuce seedlings (Lactuca sativa) in a pot experiment. SNP (8.94 mg) was applied into Cd-contaminated soil directly or added into a capsule, a paper bag, starch-coated granules, or foliar application. Cd (50 mg kg− 1) reduced chlorophyll content, caused oxidative stress, increased Cd accumulation in roots and leaves, and inhibited the uptake of calcium (Ca), magnesium (Mg), and iron (Fe). The addition of exogenous NO in Cd-contaminated soil increased chlorophyll content, improved antioxidant enzyme activities, promoted the uptake of Ca, Mg, and Fe, reduced Cd-induced oxidative damages, and inhibited Cd transferred from roots to shoots. Moreover, SNP supplied with different approaches had varied effects on Cd tolerance of lettuce seedlings. The alleviated effect of SNP applied into soil directly was the worst, and the three SNP slow release materials ...

Whereas chronological age (CA) cannot distinguish functional differences among individuals of the same age, the biological age (BA) may be used to reflect the functional state of the body. The purpose of this study was to construct an integral formula of the BA, by using principle component analysis (PCA).The vital organ function of 505 healthy individuals of Han origin (age 35-91 years) was examined. A total of 114 indicators of cardiovascular, pulmonary, and brain functions, and clinical, inflammatory, genetic, psychological, and life habit factors were assessed as candidate indicators of aging. Candidate indicators were submitted with CA to correlation and redundancy analyses. The PCA method was used to build an integral formula of the BA for the population.Seven biomarkers were selected in accordance with a certain load standard. These biomarkers included the trail making test (TMT), pulse pressure (PP), mitral valve annulus ventricular septum of the peak velocity of early filling (MVES), minimum carotid artery intimal-medial thickness (IMTmin), maximum internal diameter of the carotid artery (Dmax), maximal midexpiratory flow rate 75/25 (MMEF75/25), and Cystatin C (CysC). The formula for the BA was: BA = 0.0685 (TMT) + 0.267 (PP) - 1.375 (MVES) + 22.443 (IMTmin) + 2.962 (Dmax) - 2.332 (MMEF75/25) + 16.104 (CysC) + 0.137 (CA) + 0.492.Several genetic and lifestyle indicators were considered as candidate markers of aging. However, ultimately, only markers reflecting the function of the vital organs were included in the BA formula. This study represents a useful attempt to employ multiple indicators to build a comprehensive BA evaluation formula of aging populations.

A pot experiment was conducted to study the effects of sodium nitroprusside (SNP, a nitric oxide [NO] donor) on cadmium (Cd) toxicity in ryegrass plants. In the present study, ryegrass plants subjected to Cd toxicity were treated with different concentrations of SNP (50, 100, 300 and 500 µM), SNP solution was poured into Cd-contaminated soil every seven days. Cd treatment inhibited the plants growth and the absorption of micronutrients, increased accumulation of Cd in both shoots and roots. In Cd-treated plants, the activities of antioxidant enzymes and the contents of proline, soluble protein and ascorbic acid (AsA) decreased dramatically, whereas the accumulation of superoxide anion (O2.-), hydrogen peroxide (H2O2) and malondialdehyde (MDA) increased significantly. Addition of SNP significantly decreased O2.-, H2O2 and MDA accumulation in both shoots and roots of Cd-stressed plants, decreased the transport of Cd from roots to shoots, alleviated the inhibition of Ca, Fe, Mg and Zn absorption induced by Cd and promoted the plant growth. In SNP-treated plants, the chlorophyll content, the contents of proline, soluble protein and ascorbic acid, and the activities of superoxide dismutase, peroxidase and catalase increased considerably. Addition of 300 µM SNP had the most significant alleviating effect against Cd toxicity while the addition of 500 µM SNP had no significant effect with Cd treatment. Based on these results, we concluded that the optimal concentrations of exogenous SNP could alleviate Cd induced stress and promote ryegrass plant growth.

Inhibiting gene expression in specific tissues and organs through intravenous injection would be the ultimately preferred method of disease therapy. Here, we report the successful delivery of lentivirus-mediated small interfering RNA (siRNA) to suppress GFP gene expression in living mice. First, a lentiviral vector with siRNA (len-siRNA) driven by H1 promoter was constructed to effectively suppress GFP expression in Mel cells. When the len-siRNA virus was injected into transgenic mice, the GFP expression was significantly suppressed (over 15% reduction) in the recipient mice compared to the control mice and the suppressing effect lasted more than 1 week after injection. Our results demonstrate a new effective approach to inhibit gene expression by siRNA and lentiviral vectors. Further development of this drug for suppression of gene expression siRNA should result in applications not only for cancers but also for infectious and immune diseases.

International audience; The nuclear fusion research goal is to demonstrate the feasibility of fusion power for peaceful purposes. In order to achieve the conditions similar to those expected in an electricity-generating fusion power plant, plasmas with a temperature of several hundreds of millions of degrees must be generated and sustained for long periods. For this purpose, RF antennas delivering multi-megawatts of power to magnetized confined plasma are commonly used in experimental tokamaks. In the gigahertz range of frequencies, high power phased arrays known as " Lower Hybrid " (LH) antennas are used to extend the plasma duration. This paper reviews some of the technological aspects of the LH antennas used in the Tore Supra tokamak and presents the current design of a proposed 20 MW LH system for the international experiment ITER.

Porous copolymers based on divinylbenzene (DVB) and methyl acrylate (MA) were prepared by suspension polymerization in the presence of toluene as porogen. By using purified DVB (98.8%), the resulting MA/DVB copolymers with a wide range of DVB contents were found to be able to swell in water directly, although both the homopolymers derived from DVB and MA are hydrophobic. The amounts of DVB and MA in the copolymers affect the water-swelling behavior profoundly. However, the direct swelling in water occurs only after the DVB or MA content reaches a critical value, and the effect of the MA content will be significant only when the DVB content is at a high level. The latter observation reflects the combined effect of the cross-linking density and the polymer polarity on the swelling ability of the MA/DVB copolymers in water. The nature of the direct swelling of these hydrophobic porous copolymers in water was discussed by considering both factors: the existence of the inner stresses in the strained polymer n...

Edge localized mode (ELM) mitigation with lower hybrid current drive (LHCD) has been observed in the HL-2A tokamak. This mitigation effect is very sensitive to the parameters as the plasma density and the LHCD absorbed power, i.e., more easily to be observed for high density and large LHCD absorbed power. The divertor peak heat load released by ELM has been significantly reduced during the mitigation phase. The pedestal density gradient is slightly reduced during ELM mitigation, and the plasma rotation velocity and ion temperature are significantly reduced by LHCD. It has been found that the ELM mitigation is not synchronized with the LHCD, while it is synchronized with the increase of the pedestal turbulence, showing that the enhancement of the transport due to the pedestal turbulence can be the direct cause of the ELM mitigation.

Recent development in the advanced intermediate temperature (400 to 700°C) ceramic fuel cell (CFC) research brings up feasibility and new opportunity to develop innovative biomass-fuelled CFC technology. This work focuses on fundamentals of the biomass-fuelled CFCs based on available biofuel resources through thermochemical conversion technologies. Both real producer gas from biomass gasification and imitative compounded gas were used as the fuel to operate the CFCs in the biomass CFC testing station. The composition of the fuel gas was varied in a wide range of practices of the present conversion technology both in KTH and Shandong Institute of Technology (SDIT). CFC performances were achieved between 100 and 700 mW cm−2 at 600–800°C corresponding to various gas compositions. A high performance close to 400 mW cm−2 was obtained at 600°C for the gas with the composition of H2 (50 per cent)+CO (15 per cent)+CO2 (15 per cent)+N2 (20 per cent) and more than 600 mW cm−2 for the H2 (55 per cent)+CO (28 per cent)+CO2 (17 per cent) at 700°C. This paper presents the experimental results and discusses the fundamentals and future potentiality on the biomass fuelled CFCs. Copyright © 2002 John Wiley & Sons, Ltd.

Using a potted experiment, we studied the effect of slow-release nitric oxide (NO) on the physiological characteristics of cotton seedlings subjected to salt stress (585 mg/kg NaCl). Sodium nitroprusside (SNP, an NO donor, 2.62 mg) was applied either directly to the soil, via slow release methods (slow-release bags, slow-release capsules, or slow-release particles), or via foliar application. NaCl decreased plant weight and chlorophyll content and increased electrolyte leakage and the contents of proline, ascorbic acid (ASA), and Na. NaCl also induced oxidative stress, as indicated by elevated levels of lipid peroxidation and ROS production. Foliar spray of SNP (0.09 mM) enhanced plant growth, promoted ion absorption and transport, and increased enzyme activity. Slow-released NO increased the levels of chlorophyll, ASA, and proline; promoted the uptake of K, Ca and Mg; and decreased Na. Moreover, increases in SOD and CAT activity were demonstrated to counter oxidative stress. However, different methods of SNP application have different effects on salt-tolerance. Foliar application was optimal. Slow-release NO, especially slow-release particles, was better able to alleviate NaCl toxicity compared with direct application of NO to the soil.

Inhibiting gene expression in specific tissues and organs through intravenous injection would be the ultimately preferred method of disease therapy. Here, we report the successful delivery of lentivirus-mediated small interfering RNA (siRNA) to suppress the GFP gene expression in living mice. First, a lentiviral vector with siRNA (len-siRNA) driven by H1 promoter was constructed to suppress GFP expression effectively in Mel cells. When the len-siRNA virus was injected into transgenic mice, the GFP expression was significantly suppressed (over 15% reduction) in the recipient mice compared to the control mice and the suppressing effect lasted more than one week after injection. Our results demonstrate a new effective approach to inhibit gene expression by siRNA and lentiviral vectors. Further development of this suppression of gene expression siRNA drug should result in applications not only for cancers but also for infectious and immune diseases.

A new ITER-relevant lower hybrid current drive (LHCD) launcher, based on the passive-active-multijunction (PAM) concept, was brought into operation on the Tore Supra tokamak in autumn 2009. The PAM launcher concept was designed in view of ITER to allow efficient cooling of the waveguides, as required for long pulse operation. In addition, it offers low power reflection close to the cut-off density, which is very attractive for ITER, where the large distance between the plasma and the wall may bring the density in front of the launcher to low values. The first experimental campaign on Tore Supra has shown extremely encouraging results in terms of reflected power level and power handling. Power reflection coefficient −2, i.e. its design value at f = 3.7 GHz. In addition, 2.7 MW has been coupled at a plasma–launcher distance of 10 cm, with a power reflection coefficient

Analysis and comparisons were made between the clinical and pathological data obtained from 42 cases of type I and 17 cases of type III membranoproliferative glomerulonephritis (MPGN). It was shown that type I MPGN differed from type III remarkably in following respects: (1) Nephrosis was a salient feature of type III while hypertension, impairment of renal function and hematuria were more common in type I. (2) Pathological glomerular sclerosis, tubular interstitial changes and crescents formation occurred frequently in type I but not in type III. (3) Long term prognosis for type III was much better than type I. It is concluded the type III MPGN is a distinct clinical entity which differs from the classical type I MPGN in many aspects.