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Global biodiversity decline and its cascading effects through trophic interactions pose a severe threat to human society. Establishing the impacts of biodiversity decline requires a more thorough understanding of multi-trophic interactions and, more specifically, the effects that loss of diversity in primary producers has on multi-trophic community assembly. Within a synthetic conceptual framework for multi-trophic beta-diversity, we tested a series of hypotheses on neutral and niche-based bottom-up processes in assembling herbivore and carnivore communities in a subtropical forest using linear models, hieratical variance partitioning based on linear mixed-effects models (LMMs) and simulation. We found that the observed taxonomic, phylogenetic and functional beta-diversity of both herbivorous caterpillars and carnivorous spiders were significantly and positively related to tree dissimilarity. Linear models and variance partitioning for LMMs jointly suggested that as a result of bottom-up effects, producer dissimilarities were predominant in structuring consumer dissimilarity, the strength of which highly depended on the trophic dependencies on producers, the diversity facet examined, and data quality. Importantly, linear models for standardized beta-diversities against producer dissimilarities implied a transition between niche-based processes such as environmental filtering and competitive exclusion, which supports the role of bottom-up effect in determining consumer community assembly. These findings enrich our mechanistic understanding of the 'Diversity Begets Diversity' hypothesis and the complexity of higher-trophic community assembly, which is fundamental for sustainable biodiversity conservation and ecosystem management.全球范围内生物多样性下降正对全球生态系统功能构成威胁。而特定类群的生物多样性下降又会通过营养级关系(例如，bottom-up effect上行效应和top-down effect下行效应)对不同营养级类群的生物多样性和整个生态系统产生复杂影响。在此背景下，揭示不同营养级之间生物多样性变化的关联机制对于理解多营养级组成的群落构建和生物多样性的维持机制至关重要。在多营养级群落构建机制的研究中，最为经典的“Diversity begets diversity”理论常常用于解释不同营养级alpha多样性的关联机制研究，而对于营养级之间多维度beta多样性的关联机制研究相对较少。 本研究依托中国亚热带生物多样性与生态系统功能 (BEF-China，江西德兴) 野外实验样地，对植物、植食性无脊椎动物(鳞翅目幼虫)和捕食性无脊椎动物(蜘蛛)的物种组成、功能特征数据进行了系统调查，并构建不同类群物种的种间系统发育关系。根据生态位理论和中性理论的预测，本研究分别在beta多样性观测值空间格局、beta多样性观测值变异解释和beta多样性标准值空间格局三个维度提出假设，系统评估了亚热带森林中植物组成(代表生态位过程中的上行效应)和空间距离(代表中性扩散过程)对这两个营养级群落构建的相对重要性。 研究表明，植食性和捕食性无脊椎动物的物种、谱系和功能beta多样性均与植物beta多样性存在显著正相关关系。基于线性混合模型的方差分解结果表明，植物组成的变化通过上行效应决定了植食性和捕食性无脊椎动物的群落组成结构，并且该影响同时受到营养级关系强度、多样性维度和数据质量(0-1数据/基于多度的数据)的影响。此外，基于零模型分析的beta多样性标准值空间格局也证实了生态位过程在植食性和捕食性无脊椎动物群落构建过程中的重要性。 综上所述，这些研究结果证实了植物beta多样性通过上行效应对其高营养级类群beta多样性的影响机制，进一步拓展了我们对亚热带森林中多营养级群落构建及生物多样性维持机制的理解。.

Background: Breast cancer (BC) is the most common cancer affecting women and the leading cause of cancer-related deaths worldwide. Compelling evidence indicates that pyroptosis, a newly discovered form of programmed cell death accompanied by inflammation and immune response, is inextricably involved in the development of cancer, and may activate tumor-specific immunity and/or enhance the effectiveness of existing therapies.Methods: We constructed a novel pyroptosis-related model, based on RNA-seq and clinical data downloaded from The Cancer Genome Atlas (TCGA). Data from a total of 1025 patients were included in this study, and the relationships among their clinicopathological features, survival, immune cell infiltration and RNA-seq expression levels were analyzed.Results: Two pyroptosis clusters were determined according to 38 pyroptosis-related genes. The proportions of tumor-infiltrating immune cells differed significantly in the two pyroptosis clusters. The GO and KEGG enrichment analysis of the differential gene expressions (DGEs) implicated that the immune-related pathways were activated. Then, a 56 pyroptosis-related genes signature, constructed by using univariate and multivariate Cox regression, was significantly associated with progression free interval (PFI), disease specific survival (DSS), and overall survival (OS) of patients with BC. Kaplan-Meier (KM) and receiver operating characteristic (ROC) analyses were conducted to confirm the clinical significance of the signature. Finally, a nomogram was constructed based on the signature to evaluate its clinical value. Cox analysis revealed that the signature was significantly associated with PFI and DSS of patients with BC. KM analysis demonstrated that the signature could efficiently distinguish high and low risk patients. Moreover, ROC analysis showed that the signature exhibited high sensitivity and specificity in predicting the prognosis of patients with BC. Patients in both gene and clinical low risk subgroup (G-C-) who received adjuvant chemotherapy had a significantly lower incidence of the clinical event than those who did not. A nomogram constructed based on the signature was effective in predicting 5- and 10-year PFI and DSS. Conclusion: This study presents a novel 56 pyroptosis-related genes signature prognostic signature significantly associated with PFI, DSS, and OS in patients with BC, and combining with TNM stage might be a potential therapeutic strategy for individualized clinical decision-making.

Background:. Vasovagal syncope (VVS) greatly impairs quality of life. The therapeutic efficacy of oral rehydration saline (ORS) for unselected VVS patients is not satisfactory due to the diverse mechanisms of the disease. Body mass index (BMI) was demonstrated to reflect blood volume to a certain extent. Therefore, the present study explored the capability of BMI to predict the therapeutic response of children with VVS to ORS treatment. Methods:. Seventy-four children with VVS who visited the Syncope Unit of Pediatrics at Peking University First Hospital from November 2010 to June 2019 receiving ORS treatment were enrolled for this retrospective case-control study. A comparison of demographic, clinical, and hemodynamic characteristics was performed between responders and non-responders. The correlation between baseline BMI and response time was analyzed. To determine the value of baseline BMI in predicting the therapeutic efficacy of ORS in children with VVS, a receiver operating characteristic curve analysis was performed. Results:. Fifty-two children were identified as responders, and the remaining 22 children were identified as non-responders. The baseline BMI of the responders was much lower than that of the non-responders (16.4 [15.5, 17.8] kg/m2vs. 20.7 ±e6 kg/m2, P

Hydrogen sulfide (H

The paper aims to provide the methods to tailor the rheological properties of silver paste for improving the fine line printing properties for crystalline silicon solar cells. The investigation on the internal structure model of silver paste was performed in order to understand the interaction among constituents in silver paste. Much stronger polymer network structure is formed through chain entanglements between thixotropic agent and polymer resin compared with the network structure originated from thixotropic agent. Silver particles have some association with above polymer network structure and form a stronger internal structure of silver paste together. The rheological properties were improved by tailoring the composition of polymer resin, using a combination of controlled flocculating dispersing additive and thixotropic agent, and the addition of nanosized carbon black. The strength of internal network structure can be enhanced by the design of polymer resin composition but without increasing high shear-rate viscosity. Through the combination use of controlled flocculating dispersing additive and thixotropic agent, the strength of network structure and viscosity can be improved. The depletion flocculation induced by the addition of nanosized carbon black introduces a new attraction force between silver particles and strengthens the internal network structure.

Background:. Vasovagal syncope (VVS) is common in children and greatly affect both physical and mental health. But the mechanisms have not been completely explained. This study was designed to analyze the gut microbiota in children with VVS and explore its clinical significance. Methods:. Fecal samples from 20 VVS children and 20 matched controls were collected, and the microbiota were analyzed by 16S rRNA gene sequencing. The diversity and microbiota compositions of the VVS cases and controls were compared with the independent sample t test or Mann-Whitney U test. The correlation between the predominant bacteria and clinical symptoms was analyzed using Pearson or Spearman correlation test. Results:. No significant differences in diversity were evident between VVS and controls (P > 0.05). At the family level, the relative abundance of Ruminococcaceae was significantly higher in VVS children than in controls (median [Q1, Q3]: 22.10% [16.89%, 27.36%] vs. 13.92% [10.31%, 20.18%], Z = −2.40, P 4, P

The formation and structure of a collisional shock wave in a fully ionized plasma is studied via full particle-in-cell simulations, which allows the complex momentum and energy transfer processes between different charged particles to be treated self-consistently. The kinetic energy of the plasma flow drifting towards a reflecting piston is found to be rapidly converted into thermal motion under the cooperative effects of ion-ion collisions, ion-electron collisions, and electric field charged-particle interactions. The subsequent shock evolution is influenced by the ``precursor'' ion beam before a quasisteady state is reached. The shock wave structure is then analyzed from a two-fluid transport viewpoint, which is found to be affected by ``flux-limiting'' electron transport, the nonthermal ions, and the charge separation electric field.

The biogenic amines (BAs), water activity, pH, thiobarbituric acid‐reactive substances (TBARS), and nitrite were, respectively, tested in dry fermented sausage with starter cultures (37x‐6 Lactobacillus plantarum, x3‐3b L. plantarum, 30x‐11 Staphylococcus pentosans, and 37x‐8 S. pentosans), during storage of room temperature (20°C) and refrigeration storage (4°C). Tryptamine (TRM), 2‐phenylethylamine (PHE), putrescine (PUT), cadaverine (CAD), histamine (HIM), and tyramine (TYM) contents of all samples were increased storage at 20°C, and the content of TRM, PUT, CAD, and HIM of all samples storage at 20°C was higher than that storage at 4°C after 42 days. The content of BA with 37x‐6, x3‐3b, and 37x‐8 was obviously decreased at 4°C storage. The storage temperature has a significant effect on BA content (p, In summary, the effect of the storage temperature and starter culture on BAs content was significant, the starter culture of x3‐3b, 37x‐6, and 37x‐8 and low temperature storage would be optimum for producing and storing fermented sausage regarding biogenic amine concentrations.

Experimental and simulation data [Moreau et al., Plasma Phys. Control. Fusion 62, 014013 (2019); Kaymak et al., Phys. Rev. Lett. 117, 035004 (2016)] indicate that self-generated magnetic fields play an important role in enhancing the flux and energy of relativistic electrons accelerated by ultra-intense laser pulse irradiation with nanostructured arrays. A fully relativistic analytical model for the generation of the magnetic field based on electron magneto-hydrodynamic description is presented here. The analytical model shows that this self-generated magnetic field originates in the nonparallel density gradient and fast electron current at the interfaces of a nanolayered target. A general formula for the self-generated magnetic field is found, which closely agrees with the simulation scaling over the relevant intensity range. The result is beneficial to the experimental designs for the interaction of the laser pulse with the nanostructured arrays to improve laser-to-electron energy coupling and the quality of forward hot electrons.

Fibrosis is a pathological feature of most chronic diseases and leads to the dysfunction of various organs. However, there is currently no effective method for treating fibrosis. In recent years, a small gas, sulfur dioxide (SO₂), which can be generated endogenously in mammals, has been found to have vasorelaxation activity, improve cardiac function and decrease myocardial injury. Endogenous SO₂ also mediates the process of fibrosis. Inhibition of endogenous SO₂ can aggravate small pulmonary artery remodeling and abnormal collagen accumulation. SO₂ treatment significantly improves pulmonary fibrosis and pulmonary arterial remodeling. Overexpression of the key enzymes associated with endogenous SO₂ generation, aspartate aminotransferase (AAT) 1 and AAT2, mimics the effect of SO₂ on the down-regulation of collagen synthesis, while AAT1 or AAT2 knockdown aggravates abnormal collagen accumulation in vascular smooth muscle cells (VSMCs). SO₂ also improves myocardial fibrosis induced by myocardial infarction or diabetes in rats, and inhibits myocardial fibroblast proliferation and migration by the extracellular signal-regulated protein kinase pathway. The mechanisms underlying the inhibition of fibrosis by SO₂ are related to its antioxidant effect, anti-inflammation effect, improvement in cardiac function, and cell proliferation inhibition. Therefore, SO₂ has a potential therapeutic effect on fibrosis.

In proton radiography, degeneracy of electric and magnetic fields in deflecting the probe protons can prevent full interpretation of proton flux perturbations in the detection plane. In this paper, theoretical analyses and numerical simulations suggest that the contributions of the electric and magnetic fields can be separately obtained by analyzing the difference between the flux distributions of two discriminated proton energies in a single shot of proton radiography. To eliminate the influence of field evolution on the separation, a strategy is proposed in which slow field evolution is assumed or an approximate estimate of field growth is made. This could help achieve a clearer understanding of the radiographic process and allow further quantitative analysis.

TRIB3 (tribblespseudokinase 3) is a pseudokinase that affects several cellular functions, and its expression is increased during endoplasmic reticulum stress (ER stress). How recurrent seizures affect the regulation of TRIB3 in the hippocampus during epilepsy remains unclear. In this study, we investigated the role of TRIB3 in the kainic acid (KA)-induced seizures and related brain injury. In a rat model of kainic acid-induced seizures, neuronal excitotoxic injury and apoptosis, and increases in the expression of TRIB3 and ER stress markers glucose-regulated protein 78 (GRP78) and C/EBP homologous binding protein (CHOP) were observed in the hippocampus by 24 h to 30 d after KA administration. Furthermore, phosphorylation of AKT, which is inhibited by TRIB3, was decreased in the hippocampus after KA-evoked seizure. These results indicate that ER stress, TRIB3 and AKT signaling are involved in the acute and prolonged hippocampal injury following KA induced seizure, suggesting that the ER stress-associated gene TRIB3 plays an important role in neuronal apoptosis after seizure.

The Weibel instability and the induced magnetic field are of great importance for both astrophysics and inertial confinement fusion. Because of the stochasticity of this magnetic field, its main wavelength and mean strength, which are key characteristics of the Weibel instability, are still unobtainable experimentally. In this paper, a theoretical model based on the autocorrelation tensor shows that in proton radiography of the Weibel-instability-induced magnetic field, the proton flux density on the detection plane can be related to the energy spectrum of the magnetic field. It allows us to extract the main wavelength and mean strength of the two-dimensionally isotropic and stochastic magnetic field directly from proton radiography for the first time. Numerical calculations are conducted to verify our theory and show good consistency between pre-set values and the results extracted from proton radiography.

Weibel instability, a subject of relevance to many fields of physics ranging from inertial confinement fusion to some astrophysical scenarios, is usually probed with the side-on proton radiography. In order to diagnose the strength and wavelength of the spontaneous fields, how to distinguish the coexisting electric and magnetic fields, and how to overcome the counteracting of deflections in radiographing the filamentary structured fields, are two concerns which must be settled. In this paper, proton radiography of the Weibel instability in two counterstreaming plasma flows is studied by simulation. It suggests that the electric field dominates the deflection of probe protons, whereas the contribution from magnetic field is ignorable. To resolve the deflection-counteracting problem, spatial spectrum of the electric field energy is found to be related with the deflection velocity of the probe beam by theoretical analyses. The strength and wavelength of the electric field is then obtainable from the proton flux on the detection plane, whereas the strength and wavelength of the magnetic field can be deduced through the equilibrium between the electric field and the magnetic field pressure gradient after the linear growth stage of the instability. Both numerical and experimental verifications suggest that our method performs well in extracting the strength and wavelength of the spontaneous electric and magnetic fields of Weibel instability from proton radiography.

The influence of ionization on the formation of plasma channel and the propagation of a relativistic electron beam in a near-critical density hydrocarbon gas are investigated by using two-dimensional (2D) particle-in-cell (PIC) simulations. A magnetic-dipole vortex is formed and self-sustained by its magnetic field pressure inside the plasma channel when the short pulse laser energy is almost depleted. After its formation, the magnetic dipole vortex moves forward with the relativistic electron beam in the plasma channel. In a fully ionized plasma, a high density plasma barrier is usually formed ahead of the plasma channel due to the density profile steepening. Therefore, the deflection of the plasma channel can easily occur during the forward movement of the magnetic dipole vortex. In contrast, the deflection of the plasma channel is suppressed by the ionization effect with hydrocarbon gas. Two main mechanisms to suppress the deflection are found. These mechanisms are the decrease of the plasma density steepening at the front of the plasma channel in a partly-ionized plasma, and the consuming of the electromagnetic field energy due to the ionization itself.

The sulfur-containing gases hydrogen sulfide (H2S)and sulfur dioxide (SO2 )were previously considered to be waste gases. Recent studies showed that they could be endogenously generated from metabolism of the sulfur-containing amino acids in mammals. Endogenous H2S and SO2 generation pathways also existed in the cardiovascular system.H2S and SO2 had important physiological effects in the cardio-vascular system including vasorelaxation and myocardial negative inotropic effect. The pathophysiological effects of H2S and SO2 in the cardiovascular system have been recognized, such as alleviating hypertension and pulmonary hypertension, inhibiting the development of atherosclerosis, and protecting against myocardial ischemia-reperfusion (I /R)injury and isoproterenol-induced myocardial injury. Adenosine triphosphate-sensitive potassium (KATP )channel, L-type calcium (L-Ca2 +) channel, cGMP, NF-κB signaling pathway and MAPK signaling pathway and so on participated in the biological effects of H2S and SO2 .The above findings suggested that H2S and SO2 were important endogenous gaseous signaling molecules in the cardiovascular system, which provided a new way to elucidate the pathogenesis and therapeutic targets of cardiovascular diseases.

Myocardial remodeling occurs after myocardial infarction (MI), the leading cause of mortality worldwide. Although myocardial fibrosis plays an important role in the process of myocardial remodeling, there is not yet an effective method of reducing it. The aim of the present study was to determine the effects of sulfur dioxide (SO₂) on myocardial fibrosis and the possible mechanisms of these effects. SO₂ treatment reduced the extent of myocardial fibrosis and post-MI levels of collagens I and III in the left-ventricular myocardium. SO₂ also improved MI-induced thinning of the left ventricular wall while enlarging the left ventricular internal diameter. SO₂ was able to reduce matrix metalloproteinase (MMP)-9 activity and increase tissue matrix metalloproteinase inhibitor (TIMP)-1 content in myocardium after MI. However, the mechanism underlying these effects of SO₂ on myocardial fibrosis are unknown. Western blot analysis of endoplasmic reticulum (ER) stress-related proteins showed that glucose-regulated protein 78, C/EBP homologous protein, caspase-12, and phosphorylated eukaryotic initiation factor 2α expression levels were significantly increased in MI rats and decreased by SO₂ treatment. The ER stress promoter dithiothreitol reversed these effects of SO₂. In conclusion, SO₂ alleviated myocardial fibrosis in MI rats through a mechanism related to inhibition of excessive ER stress.

The Dual-Channel Network proposed in our previous work can improve the code resource utilization efficiency. Carrier Sense Random Packet (CSRP) CDMA and Partitioned Slot Reservation Packet (PSRP) CDMA were proposed for enhancing the control channel interference resistance of Dual-Channel Networks. In this paper, we investigate CSRP-CDMA and PSRP-CDMA, and derive the performance analytic models by taking into account both intra-cluster MAI and inter-cluster MAI. The models provide the expressions of packet transmission probability and normalized network throughput. Furthermore, the probability of packet successful transmission and the throughput performance are compared between the two protocols. Finally, we analyse the influence on the network performance with spread spectrum gains and network scale. The numerical results show that, normalized network throughput of PSRP-CDMA outperforms CSRP-CDMA by 20% to improving the code resource utilization efficiency of control channel of Dual-Channel Networks.

Sulfur dioxide (SO₂) is a toxic gas and air pollutant. The toxic effects of SO₂ have been extensively studied. Oxidative damage due to SO₂ can occur in multiple organs. Inhaled SO₂ can also cause chromosomal aberrations, DNA damage and gene mutations in mammals. However, SO₂ can also be generated from the sulfur-containing amino acid, L-cysteine. Recent studies have shown that SO₂ has a vasorelaxant effect, and ameliorates pulmonary hypertension and vascular remodeling. SO₂ can also reduce lung injury and myocardial injury in rats. In addition, SO₂ reduces myocardial ischemia-reperfusion injury and atherosclerotic lesions. Therefore, SO₂ exerts both detrimental and protective effects in mammals. Is SO₂ a foe or friend for life?.

In order to improve the seeding efficiency and quality of water-saving mulch planters, a kind of multifunction mulch planter with laying irrigation tape was designed based on duckbill type precision seed metering device. It broke the pattern of single planting machine and realized duplex joint seeding operations. The seeding and film mulching performance were also improved by optimizing the seed metering device and film laying device. The planter has the characteristics of simple operation, less investment, reliable performance and good film-mulching result. The result of field test showed that: the average seed space is 150mm; the working speed is 4.3km/h; the pass rate of grain distance is 96.7%; the vacancy rate is 0.8%, the pass rate of seed number is 99.2%. So the sowing quality of the planter is well.

The gasotransmitter nitric oxide was classified as the first endothelium-derived relaxant factor, and opened a new era in cardiovascular research. Another small gas, sulfur dioxide (SO₂), can also be generated endogenously in mammals. Recent studies have shown that SO₂ may play important roles in the cardiovascular system. At low concentrations, the vasodilatory effect of SO₂ is endothelium-dependent. The vasodilation induced by an endothelium-derived relaxant factor is achieved by the opening of potassium channels, and hyperpolarization of the membranes of vascular smooth muscle cells. This feature is in accordance with that of SO₂. The vasodilatory effect of SO₂ is related to the opening of adenosine triphosphate-sensitive potassium channels and high-conductance calcium-activated potassium channels. The 3'-5'-cyclic guanosine monophosphate pathway and activation of nitric oxide synthase are also involved in the endothelium-derived relaxant factor effect of SO₂. The vasodilatory effect of gaseous SO₂ is much stronger than that of its derivatives (bisulfite and sulfite). It is suggested that SO₂ may be a candidate endothelium-derived relaxant factor, which could lead to a new era of research into cardiovascular disease in mammals.

The electric and magnetic fields generated by the Weibel instability, most of which have a tube-like structure, are of importance for many relevant physical processes in the astrophysics and the inertial confinement fusion. Experimentally, proton radiography is a commonly used method to diagnose the Weibel instability, where the proton deflection introduced from the self-generated electric field is usually ignored. This assumption, however, is in conflict with the experimental observations by Quinn, Fox and Huntington, et al. because the magnetic field with a tube-like structure cannot introduce parallel flux striations on the deflection plane in the proton radiography. In this paper, we re-examine the nature of the proton radiography of the Weibel instability numerically. Two symmetric counterstreaming plasma flows are used to generate the electron Weibel instability with the three-dimensional particle-in-cell simulations. The proton radiography of the Weibel instability generated electric and magnetic fields are calculated with the ray tracing method. Three cases are considered andcompared: only the self-generated electric field E is included, only the self-generated magnetic field B is included, both the electric field E and magnetic field B are included. It is shown that when only E is included, the probe proton flux density perturbation on the detection plane, i.e., δn/n0, is much larger than that when only B is included. Also, when both E and B are included, δn/n0 is almost the same as that when only E is included. This suggests that in the proton radiography of the Weibel instability generated electric and magnetic fields, the deflection from the electric field dominates the radiography, whereas the magnetic field has an ignorable influence. Our conclusion is quite different from that obtained on the traditional assumption that the electric field is ignorable in the radiography. This mainly comes from the spatial structure of the Weibel instability generated magnetic field, which is tube-like and points to the azimuthal direction around the current filaments. When the probe protons pass through the field region, the deflection from the azimuthal magnetic field can be compensated for completely by itself along the passing trajectories especially if the deflection distance inside the field region is small. Whereas for the electric field, which is in the radial direction, the deflection to the probe protons will not be totally compensated for and will finally introduce an evident flux density perturbation into the detection plane. This understanding can beconducive to the comprehension of the experimental results about the proton radiography of the Weibel instability.

This paper analyses the performance of distributed transmit beamforming in presence of oscillator phase noise. Average beampattern of arbitrary array is adopted here as performance index. In the analysis, the phase noise process of each node oscillator is described by a stationary model taking into account 1/f3 and 1/f2 shape single-sideband (SSB) spectrum. By using non-parametric kernel method, the average beampattern in presence of phase noise is derived and corresponding beampattern characteristics are evaluated. Theoretical analysis and simulation results show that the accumulated PN can result in the degradation of DTBF performance, which are also reflected in the change of beampattern characteristics, such as 3db width, 3db sidelobe region and average directivity. With the increase of time duration, the cumulative phase noise becomes greater and the degradation is more obvious.

The sheath electric field is localized with a thickness of only several Debye lengths. It widely exists at plasma boundaries and in some cases can be very intense. Previous diagnoses of an intense, localized sheath electric field could only deliver the spatially averaged amplitude of the field. The sheath’s spatial structures remain unresolved. In this paper, we numerically demonstrate the three-dimensional reconstruction of a cylindrically symmetric sheath electric field by means of the Abel inversion in combination with a correction of the spatial dislocation in the inversion process. By employing a divergent or/and relativistic proton beam for radiography of the sheath region, it is found that the crossings of the proton trajectories can be prevented and the linearity requirement for the Abel inversion can be satisfied. A sheath electric field with an amplitude of about 1×1011 V/m and a thickness of sub-μm level is well reconstructed with a 120 MeV proton beam. The inter dependences of the reconstruction on the proton beam energy, energy spread, beam divergence, and the amplitude of the sheath are discussed.The sheath electric field is localized with a thickness of only several Debye lengths. It widely exists at plasma boundaries and in some cases can be very intense. Previous diagnoses of an intense, localized sheath electric field could only deliver the spatially averaged amplitude of the field. The sheath’s spatial structures remain unresolved. In this paper, we numerically demonstrate the three-dimensional reconstruction of a cylindrically symmetric sheath electric field by means of the Abel inversion in combination with a correction of the spatial dislocation in the inversion process. By employing a divergent or/and relativistic proton beam for radiography of the sheath region, it is found that the crossings of the proton trajectories can be prevented and the linearity requirement for the Abel inversion can be satisfied. A sheath electric field with an amplitude of about 1×1011 V/m and a thickness of sub-μm level is well reconstructed with a 120 MeV proton beam. The inter dependences of the reconstructi...

BACKGROUND: Neonicotinoids are widely used as seed treatments in wheat fields against the grain aphid (Sitobion avenae F.) in China. Due to the degradation of neonicotinoids in wheat plants, wheat aphids are more likely to be exposed to low concentrations of neonicotinoids over long periods. It is therefore expected that neonicotinoids, aside from acute (lethal) effects, may also cause a range of sub-lethal effects on this pest. RESULTS: The growth and fertility of S. avenae feeding on wheat plants treated with a sub-lethal concentration (LC10) of imidacloprid, dinotefuran, thiacloprid and thiamethoxam were not greatly affected. However, the population growth parameters of S. avenae were significantly reduced at median lethal concentration (LC50). Electronic penetration graph recordings showed a higher percentage of no probing phase and shorter phloem sap ingestion phase on the wheat plants treated with LC10 and LC50 concentrations. CONCLUSION: The results indicate that even low concentrations of neonicotinoid treatments on wheat seeds have long-term, adverse effects on wheat aphid. As such, neonicotinoid seed treatments have far greater effects on wheat aphids than estimated by acute toxicity tests. These results benefit our understanding on the subtle effects of the four tested neonicotinoids when applied as seed treatments. c � 2013 Society of Chemical Industry

Despite plenty of reports on the preparation of SnS films, it remains challenging to grow SnS microrods films. In this paper, we describe a facile synthesis of the SnS microrods films, utilizing constant potential cathodic electro-deposition method, as well as the investigation of its structure and optical properties. The synthesis involves a mixture of stannous sulfate, EDTA and sodium thiosulfat. Preliminary studies on the growth mechanism indicate that SnS films are preferentially oriented along the (101) plane, which is quite different from the previous report that oriented along the (111) plane. Raman spectra indicate that the microrods films have a high purity.