We report on experimental observation of non-laminar proton acceleration modulated by a strong magnetic field in laser irradiating micrometer aluminum targets. The results illustrate the coexistence of ring-like and filamentation structures. We implement the knife edge method into the radiochromic film detector to map the accelerated beams, measuring a source size of 30–110 μm for protons of more than 5 MeV. The diagnosis reveals that the ring-like profile originates from low-energy protons far off the axis whereas the filamentation is from the near-axis high-energy protons, exhibiting non-laminar features. Particle-in-cell simulations reproduced the experimental results, showing that the short-term magnetic turbulence via Weibel instability and the long-term quasi-static annular magnetic field by the streaming electric current account for the measured beam profile. Our work provides direct mapping of laser-driven proton sources in the space-energy domain and reveals the non-laminar beam evolution at featured time scales.

The Straw-headed Bulbul Pycnonotus zeylanicus is one of South-East Asia’s most threatened songbirds due to relentless demand for the regional cage-bird trade. The species was recently uplisted from ‘Endangered’ to ‘Critically Endangered’ only two years after its previous uplisting. Intriguingly, populations in highly urbanised Singapore appear relatively secure. However, the last Singaporean density estimates, derived from traditional census methods, were obtained nearly two decades ago in 2001. A recent population estimate in 2016 was derived from the census work in 2001 coupled with relative abundance indices from population trends. We thus performed systematic field surveys using the distance sampling method, estimating 573 ± 185 individuals nation-wide, with a break-down of 217 ± 81 on the main island of Singapore and 356 ± 104 birds on the satellite of Pulau Ubin. Taken together, the total population estimate reported here comprises 22.9–57.3% of the global wild population, underscoring the importance of Singapore as a stronghold for the species. In spite of its apparently secure status in Singapore, the species remains susceptible to local and foreign trapping pressures. Based on our assessment, we propose a number of local and regional conservation measures to ensure the continued survival of populations in Singapore.

We investigated the first presence of qnrA among Shigella sonnei clinical isolates in Jiangsu Province, China. The qnrA-positive isolates coexisted with the mutation in gyrA at codon 83, these isolates were resistant to nalidixic acid and 22·2% (2 of 9) of them were resistant to norfloxacin.

Deploying resistant cultivars is an economical and essential management method in controlling viral diseases, and there are several mutational resources for tobacco. In the present study, the inoculation of tobacco plants with tobacco viruses was performed in a greenhouse from 2011 to 2014 to identify mutants resistant to tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV). The high-throughput screening included seeding uniformly, transplanting in seedbeds, inoculating by cloth brushes and reporting symptoms based on disease indices. A total of 4000 second generation segregating (M2) mutants of tobacco cultivar Zhongyan100 were screened. Seeds from highly resistant mutant M2 plants were selected and planted separately. The M3 were grown and mutational stability was measured. For TMV, ten highly resistant plants were selected in the M2 generation and the mutation rate was 0·012%. In the M3 generation, there were seven mutants with hereditary high resistance and, according to the results of real-time polymerase chain reaction, the N gene was detected in all seven M3. Two hereditary immune M4 mutants, one of which was a male sterile line, were identified and evaluated in the glasshouse and in the field. For CMV, seven highly resistant plants were selected from the M2 generation and the mutation rate was 0·009%. In the M3 generation, there was one mutant with hereditary high resistance. The results indicate that hereditary mutants may be identified in the M4 generation and back-crossed to wild-type Zhongyan100 to identify anti-viral genes.

We studied seasonal patterns of swine hepatitis E virus (HEV) infection in China. From 2008 to 2011, 4200 swine bile specimens were collected for the detection of HEV RNA. A total of 92/2400 (3·83%) specimens in eastern China and 47/1800 (2·61%) specimens in southwestern China were positive for HEV. Seasonal patterns differing by geographical area were suggested. In eastern China, the major peak of HEV RNA prevalence was during March–April, with a minor peak during September–October, and a dip during July–August. In southwestern China, the peak was during September–October and the dip during March–April. The majority of subtype 4a cases (63/82, 76·83%) were detected in the first half of the year, while the majority of subtype 4b cases (26/29, 89·66%) were concentrated in the second half of the year, suggesting that different subtypes contribute to different peaks. Our results indicate that the distribution of HEV subtypes is associated with seasonal patterns.

In order to investigate the dynamics of Septin4 (Sept4) expression and its function in the formation of fibrotic livers in mice infected with Schistosoma japonicum, we constructed the mouse model of S. japonicum egg-induced liver fibrosis for 24 weeks. Immunohistochemical staining, qRT-PCR and Western blot were used to detect the expression of Sept4 and α-smooth muscle actin (α-SMA). We found Sept4 localized in the perisinusoidal space where hepatic stellate cells (HSCs) distribute in the periphery of circumoval granulomas and the portal venule. The expression of Sept4 and α-SMA had a similar significant tendency of an up-regulation to a peak at 12 weeks post-infection (p.i.) followed by a down-regulation. At 24 weeks p.i. both were at a low level. These results suggest that Sept4 and α-SMA may interact together in HSCs. Based on this evidence, we hypothesize that Sept4 seems to be involved in the formation of inflammatory granulomata and subsequent liver fibrosis by regulating HSCs activation.

Genetic polymorphisms of the LMP/TAP gene coded by the HLA-II region may be associated with outcomes of HBV infection. We conducted a case-control study to test the hypothesis, including a persistent group of 155 patients with chronic hepatitis B and 36 healthy carriers, a recovered group of 165 individuals spontaneously recovered from HBV infection, and an uninfected group of 278 healthy normal controls. Genotypes of eight polymorphisms of the LMP/TAP gene were analysed by PCR–RFLP. A logistic regression model was used to analyse statistical differences in polymorphisms or haplotypes in different groups. Of the eight polymorphisms, two (TAP1 codon 637 and LMP7 codon 145) were observed to have statistically significant association with outcomes of HBV infection (P<0·05). The two-locus haplotype constructed with two such polymorphisms was analysed. The frequencies of haplotypes B (Asp-Lys), C (Gly-Gln), and D (Gly-Lys) were found to be increased significantly in the persistent group, compared to healthy controls (OR 2·26, 95% CI 1·62–3·15, P<0·001; OR 2·37, 95% CI 1·69–3·32, P<0·001; OR 4·38, 95% CI 1·78–10·77, P=0·001, respectively). The prevalence of haplotypes B (Asp-Lys), C (Gly-Gln), and D (Gly-Lys) were also significantly higher in the persistent infectious group than in the recovered group (OR 2·68, 95% CI 1·81–3·98, P<0·001; OR 2·40, 95% CI 1·62–3·55, P<0·001; OR 3·03, 95% CI 1·22–7·55, P=0·017, respectively). These findings indicated that genetic polymorphisms of the LMP/TAP gene might be an important factor in determining the outcome of HBV infection.

Saunders's Gull Larus saundersi is a breeding endemic of Common Seepweed Suaeda glauca habitats on the east coast of China and south-west coast of South Korea. Much of this habitat has been lost and degraded due to human land use and expansion of the introduced Smooth Cordgrass Spartina alterniflora. Yancheng National Nature Reserve (NNR) is one of three breeding and wintering areas in China. We used satellite images from 1992 to 2007 and visual interpretation combined with ground truthing to classify the land cover and quantify changes in land use and land cover (LULC) in areas of Yancheng NNR used by Saunders's Gull. The Common Seepweed habitat, in which this species nests, decreased in area by 79.1% (27,358 ha) over 15 years, predominantly as a result of conversion to aquaculture ponds (18,929 ha), and is now centred in the south-east of Yancheng NNR. The total population size of Saunders's Gull was maintained at over 900 individuals from 1999 to 2006 in Yancheng NNR, but was only 575 in 2007, and the number of breeding sites decreased from eight in 1992 and 1994 to a single site in 2000–2006 and two sites in 2007. From 1999 to 2007, the breeding population in the core area of Yancheng NNR accounted for 94.93% of the total population, and its nest-site spatial turnover rate was 0.84 ± 0.08 (n = 7 years), but it tended to decrease by about 40% in 2007 because of degradation of the Common Seepweed community. The conversion of Common Seepweed habitats to other habitat types and expansion of introduced Smooth Cordgrass were the major and direct reasons for the loss and degradation of breeding habitats of Saunders's Gull. Smooth Cordgrass habitats increased in area by 321.9% (11,057 ha) during this period and centred on the east, gradually occupying the mudflats, except the beach from Liangduo River to the south of Yancheng NNR, where potential breeding sites for the Saunders's Gull could be located. We discuss the implications of our results for the conservation this species and management of its habitats.

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

The Experimental Advanced Superconducting Tokamak (EAST) has a major radius of R0 = 1.75 m and a midplane halfwidth of 0.5 m. It has been operated with a toroidal magnetic field B0 = 2 T and Ip ≤ 500 kA. The evolution of the plasma equilibrium is analysed between discharges by Equilibrium Fitting Code (EFIT). Limiter, single-null and double-null diverted configurations have been produced. A plasma elongation in the range 1.3 ≤ κ ≤ 1.9 and a triangularity in the range 0.1 ≤ δ ≤ 0.55 have been sustained. The operation space of elongated discharges is also presented based on the EAST database.

A matched and serologically confirmed case-control study was carried out to investigate the source of an outbreak of acute hepatitis involving 290000 cases in the suburbs of Shanghai, in January 1988. A total of 132 patients with acute hepatitis from six different hospitals were chosen as cases and the same number of control patients without hepatitis were matched for gender, age, admission date and area of residence. Serum specimens from both case and control patients were detected for specific anti-hepatitis A (HA) IgM antibody and a questionnaire was used to investigate probable risk factors related to the outbreak. The positive rate of anti-HA IgM was 98·48% in the case group and only 0·76% in the control, indicating that the infection was caused by HA virus. The results revealed that the source and mode of transmission were due to the consumption of contaminated and inadequately cooked clams (Anadara subcrenata lischke). There was a highly positive dose-response relationship between the odds ratio of contracting HA and the quantity or frequency of clam consumption. The odds ratios of acquiring HA from clams were up to 62·4–63·4 by both group stratification and multiple unconditional logistic regression analyses.

Many object surfaces involve a number of pieces, expressed by different equations. Previous methods of optimal grasp planning can hardly cope with such cases. Ding et al. solve this problem by characterizing the object surface with convex facets and discrete points, then selecting the eligible ones for force-closure, and finally seeking the optimal contact positions on the selected elements. So far, however, no point contact with friction (PCwF) but only frictionless point contacts (FPC) can be used on the facets, while soft finger contacts (SFC) are excluded at all. In this paper, to the above two surface elements we add line segments. Moreover, the limitations on the contact types are completely removed. A general condition and a quantitative criterion of eligibility are presented, followed by a heuristic algorithm and an iterative algorithm for finding the better eligible elements. Three common examples show: the new advances make the formerly tough problems smoothly solvable.

Silver phenylacetylide prepared by one-step process was characterized as a linear coordinated polymeric compound by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectroscopy. Its prominent third-order optical nonlinearity was detected by heterodyned ultrafast optical Kerr effect (OHD-OKE) measurement. The second-order hyperpolarizability was enhanced by 2 orders of magnitude by means of incorporation of proper electron-pushing groups. The structure status was further investigated by quantum chemical calculation and molecular modeling.

Zinc powder reacts with equivalent elemental selenium in solvent ethylenediamine at 120 °C for 6 h to form a complex, which is converted to ZnSe nanoparticles by pyrolysis or protonization. X-ray diffraction results suggest that the as-formed products have wurtzite structure. Transmission electron microscopy observation show that particles with spherical and laminar morphology were produced by pyrolysis and protonization, respectively. The formation of ZnSe nanoparticles is also investigated by infrared and thermal analysis.

The present work further develops the microbridge testing method to characterize mechanical properties of bilayer thin films. A closed-form formula for deflection versus load under small deflection is derived with consideration of the substrate deformation and residual stress in each layer. The analysis shows that the solution for bending a bilayer beam is equivalent to that for bending a single-layer beam with an equivalent bending stiffness, an equivalent residual force and a residual moment. One can estimate the Young's modulus and residual stress in a layer if the corresponding values in the other layer are known. The analytic results are confirmed by finite element calculations. The microbridge tests are conducted on low-temperature-silicon oxide (LTO)/silicon nitride bilayer films as well as on silicon nitride single-layer films. All microbridge specimens are prepared by the microfabricating technique. The tests on the single-layer films provide the material properties of the silicon nitride films. Then, applying the proposed method for bilayer films under small deflection yields the Young's modulus of 37 GPa and the residual stress of -148 MPa for LTO films.

Single-phase nanocrystalline Co9S8 was prepared by hydrothermal treatment of Co(Ac)2 and NH2CSNH2 in hydrazine solution at 170 °C. The products were characterized by x-ray powder diffraction (XRD) technique, transmission electron microscope (TEM), and wet chemical analysis. XRD indicated the product was the cubic Co9S8 phase. The relative crystallite size was 6.3 nm as determined by the Scherrer method. TEM images showed the particles were agglomerative. The electron diffraction pattern also revealed their nanocrystalline nature. In this hydrothermal formation process of Co9S8, hydrazine was a critical factor. The formation process is discussed.

The present work proposes a novel microbridge testing method to simultaneously evaluate the Young's modulus, residual stress of thin films under small deformation. Theoretic analysis and finite element calculation are conducted on microbridge deformation to provide a closed formula of deflection versus load, considering both substrate deformation and residual stress in the film. Silicon nitride films fabricated by low pressure chemical vapor deposition on silicon substrates are tested to demonstrate the proposed method. The results show that the Young's modulus and residual stress for the annealed silicon nitride film are respectively 202 GPa and 334.9 MPa.

A bulk sample of La0.6Mg0.4MnO3 has been prepared from coprecipitated carbonate precursor for the first time in this study. Structure analysis conducted by powder x-ray diffraction indicates that the sample is in the cubic perovskite phase. It shows a metal-insulator transition at 115 K (Tp) When applied to an external field, GMR effects are observed in the whole measured temperature range. The maximum negative MR value reaches as large as 480% at 105 K and 5 T. There may be two different mechanisms governing the GMR effects in the sample for the temperatures below and above Tp.

Copolymer latexes of poly(styrene/acrylic acid) were closely packed into two-dimensional arrays on glass, mica and silicon substrates respectively. When the small latexes were negatively charged due to −SO4− and −COO− groups on the surface, their film formation, in some degree, was affected by the electrostatic interaction between two particles as well as capillary force. Different electrolytes were added into the colloid to adjust the particle interaction so that the attractive and the repulsive forces were properly balanced and the ordered arrays were achieved. Thin metal film was deposited on the latex monolayer through thermal evaporation in vacuum. Then, the spheres were dissolved away to leave behind a surface with features located where the interstitial spaces between the densely packed spheres had been. This process depended upon the interaction between the microspheres and the substrates, and the adhesion between the film materials and the substrates. Different patterns of honeycomb net, triangle islands and separate spots can be obtained by controlling the ultrasonic time and intensity.