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Reconfigurable Intelligent Surfaces (RISs) have received a great deal of attention from the wireless communication community due to their powerful ability to improve the wireless communication environment. Dual-band RIS enables aperture to share two bands, improving spectrum utilization in wireless communications and thus expanding communication capacity. However, most of the reported dual-band RISs cannot achieve independent controls of the dual-band phases, which greatly limits their practical application in wireless communications. In this paper, we propose a dual-band 3-bit RIS to achieve independent controls of the reflection phases in two frequency bands by designing two tunable structures without raising the profile. It also exhibits low sensitivity to incident angles between 0� and 50�. Thereafter, the beam steering ability of the proposed RIS is further investigated with experiments under normal and oblique incidences at two frequencies, which demonstrates the powerful potential of RISs to manipulate the electromagnetic wave propagation environment.

Environmental RNA viruses are ubiquitous and diverse, and probably have important ecological and biogeochemical impacts. Understanding the global diversity of RNA viruses is limited by sampling biases, dependence on cell culture and PCR for virus discovery, and a focus on viruses pathogenic to humans or economically important animals and plants. To address this knowledge gap, we generated metatranscriptomic sequence data from 32 diverse environments in 16 provinces and regions of China. We identified 6,624 putatively novel virus operational taxonomic units from soil, sediment and faecal samples, greatly expanding known diversity of the RNA virosphere. These newly identified viruses included positive-sense, negative-sense and double-strand RNA viruses from at least 62 families. Sediments and animal faeces were rich sources of viruses. Virome compositions were affected by local environmental factors, including organic content and eukaryote species abundance. Notably, environmental factors had a greater impact on the abundance and diversity of plant, fungal and bacterial viruses than of animal viromes. Our data confirm that RNA viruses are an integral part of both terrestrial and aquatic ecosystems.

A novel graphene-based narrow band-pass frequency selective surface is proposed. This unit mainly includes two layers of square patches and a layer of complementary cross structure. The full wave simulations show that the unit attains a high transmission amplitude with the bandwidth of 100MHz in X-band, resulting in an extremely narrow passband. In addition, the performance is verified by the equivalent circuit theory. The narrow-band characteristics of this unit is advantageous for RF filtering applications.

Despite increasing evidence that antibiotic resistant pathogens are shared among humans and animals, the diversity, abundance and patterns of spread of antibiotic resistance genes (ARGs) in wildlife remains unclear. We identified 194 ARGs associated with phenotypic resistance to 13 types of antibiotic in meta-transcriptomic data generated from a broad range of lower vertebrates residing in both terrestrial and aquatic habitats. These ARGs, confirmed by PCR, included those that shared high sequence similarity to clinical isolates of public health concern. Notably, the lower vertebrate resistome varied by ecological niche of the host sampled. The resistomes in marine fish shared high similarity and were characterized by very high abundance, distinct from that observed in other habitats. An assessment of ARG mobility found that ARGs in marine fish were frequently co-localized with mobile elements, indicating that they were likely spread by horizontal gene transfer. Together, these data reveal the remarkable diversity and transcriptional levels of ARGs in lower vertebrates, and suggest that these wildlife species might play an important role in the global spread of ARGs.

Epizootic pathogens pose a major threat to many wildlife species, particularly in the context of rapidly changing environments. Pangolins (order Pholidota) are highly threatened mammals, in large part due to the trade in illegal wildlife. During July to August 2018 four sick wild pangolins (three Manis javanica and one Manis pentadactyla) exhibiting a variety of clinical symptoms were rescued by the Jinhua Wildlife Protection Station in Zhejiang province, China. Although three of these animals died, fortunately one recovered after 2 weeks of symptomatic treatment. Using meta-transcriptomics combined with reverse transcription polymerase chain reaction (RT-PCR), we identified two novel RNA viruses in two of the dead pangolins. Genomic analysis revealed that these viruses were most closely related to pestiviruses and coltiviruses, although still highly genetically distinct, with more than 48 and 25 per cent sequence divergence at the amino acid level, respectively. We named these Dongyang pangolin virus (DYPV) and Lishui pangolin virus (LSPV) based on the sampling site and hosts. Although coltiviruses (LSPV) are known to be transmitted by ticks, we found no evidence of LSPV in ticks sampled close to where the pangolins were collected. In addition, although DYPV was present in nymph ticks (Amblyomma javanense) collected from a diseased pangolin, they were not found in the local tick population. Epidemiological investigation revealed that both novel viruses might have been imported following the illegal international trade of pangolins. Hence, these data indicate that illegal wildlife trafficking not only threatens the status of pangolin populations, but may also spread epizootic pathogens.

Red-bed soft rock covers a large area in China and is often used as filling materials for highway roadbed and embankment, while the disintegration of red-bed soft rock often causes serious settlement of the roadbed and decreased stability. To thoroughly study the disintegration properties of red-bed soft rock, a series of slake durability tests were performed using different test methods. First, the gradation of disintegrated red-bed soft rock was investigated, and the shape of the gradation curve mainly presented as reverse sigmoidal and hyperbolic. Moreover, the evolution model of the disintegration breakage of red-bed soft rock using the Morgan-Mercer-Florin (MMF) model was derived, and the model parameters were analysed. Based on the test results, the disintegration behaviours of red-bed soft rock were measured by the disintegration ratio; then, the new formula to calculate the disintegration ratio based on the concept of the traditional disintegration ratio was derived using the established model. Finally, the effect of different test methods, i.e., different test devices, drying temperatures and sizes, on disintegration breakage under cyclic wetting and drying was analysed, and the test results showed that the rate of disintegration was accelerated by the slake durability apparatus, a higher drying temperature and a larger size.

Ballast degradation has a strong effect on railway track performance (including accumulative deformation, ballast resistance, and drainage). The main objective of this research is to determine the evolution of roundness during ballast degradation and investigate the mechanical properties of real ballast shape at different abrasion stages. To this end, the Los Angeles (LA) abrasion test is conducted on three groups of fresh ballast materials with different sizes (i.e., 25–30 mm, 40–50 mm, and 50–60 mm). Then, a homemade image-acquisition platform is used to extract ballast outlines from multiple projection directions. Next, the corner sharpness of the degraded ballast is quantified by particle roundness. The LA abrasion test shows that particle roundness gradually increases with increasing abrasion. Subsequently, biaxial shear tests are performed on ballasts with different roundness characteristics based on the discrete element method (DEM). The shear behaviours of degraded ballasts with different degrees of roundness are investigated through macroscopic (e.g., the shear strength and dilatancy response) to microscopic (e.g., the mean coordination number, the ratio of sliding contacts, and the mean particle contact moment) analyses. The results show that the shear strength slightly increases in the peak state, while a substantial reduction in shear strength is observed in the residual state with increasing roundness. Moreover, the microscopic analysis shows that greater roundness results in a smaller mean coordination number, as well as decreases in the ratio of sliding contacts and the mean particle contact moment.

0940 type cushion of E-flute corrugated paperboard is selected as the research object. By changing the load area, side breadth and the height of the cushions separately, static compression tests were done. The effects of structural parameter to cushioning property were analyzed through energy absorption method. It is useful to promote the application of corrugated board cushion.

Biscuit, as a common snack, in order to attract the children’s attention, besides its taste and shape, packaging design is equally important. The beautifully decorated surface of the box can be divided into a number of blocks (4 or 9) by setting the punch lines. After the biscuits are eaten up, tear the box along the punch lines, then it becomes a simple jigsaw puzzle. Inside the box except the biscuits bag, a cute clamp like scissors added. So the children can gripping biscuits by the clamp rather than by hand directly.

At present, the detection accuracy of monitoring method by human ears is not satisfying in the pure tone detection of on-vehicle loudspeakers. To solve this problem, a new method is proposed to convert vehicle loudspeakers response signals into a two-dimensional image signal via wavelet packet analysis, which can increase the time-frequency of malfunction information. Through image binaryzation and pretreatment image-edge detection, the resulting signal would be recognized with box-counting dimension acquired in the process of gaining time-frequency image through fractal dimension as malfunctioned indications. Experiments show a rate of fault recognition as high as 95% , which meet the requirements of online vehicle loudspeaker detection.

Estimates for multilinear Hilbert operators on central Morrey spaces and Morrey spaces are obtained.The best constants for the Hilbert operators on Morrey Spaces is obtained, under some condition.

Schrödinger operator; Weighted BMO spaces; Reverse Hölder inequality; Commutator Abstract. In this paper, the Schrödinger operator on n dimensions Euclid space with the non-zero, nonnegative potential function satisfying the reverse Hölder inequality is considered. The weighted boundedness of the commutators composed of several Riesz transforms associated with the Schrödinger operator and weighted BMO function on weighted Lebesgue integral spaces are obtained, for some weighted function.

In this paper, the Schrödinger operator on n dimensions Euclid space with the non-zero, nonnegative potential function satisfying the reverse Hölder inequality is considered. The weighted boundedness of the commutators composed of several Riesz transforms associated with the Schrödinger operator and weighted Lipschitz function on weighted Lebesgue integral spaces are obtained, for some weighted function.

A microextraction technique of solid phase membrane tip extraction (SPMTE) prior to gas chromatograph was developed to determine fifteen pesticides (organochlorine （OCPs） and pyrethroid). In the SPMTE procedure, multiwalled carbon nanotubes (MWCNTs) were used as the adsorbent enclosed in SPMTE device and then several important parameters influenced extraction efficiency were comprehensively optimized. Under the optimum conditions, the method obtaine good linearity in the range of 1–500.0 and 1.5–750.0 ng mL-1for OCPs and pyrethroid pesticides, low limits of detection in the range of 0.018–1.064 ng mL-1(S/N=3). Seven target analytes are detected in river sample, none of the other samples tested show any pesticide residue. The developed method is a simple, feasible, and inexpensive microextraction technique.

Tobacco stem and tobacco dust made reconstituted tobacco paper-base with a paper-making method, effect of extracted and refined on tobacco stem and tobacco dust, particular effect of tobacco stem and tobacco dust ratio on physical properties, chemical composition and microstructure of reconstituted tobacco paper-base were studied. The results indicated that the content of water soluble sugars, total alkaloid, chloride, total nitrogen of the extracted tobacco stem and extracted tobacco dust were decreased, content of holocellulose was increased. With decreasing of tobacco stem pulp ratio (increasing of tobacco dust pulp ratio) of reconstituted tobacco paper-base, there was rapid decrease in tensile index, tear index, bulk and air permeability of reconstituted tobacco paper-base. The scanning electron microscopy (SEM) showed that tobacco dust ratio more than 30%, bulk of reconstituted tobacco paper-base decreased significantly. Content of water soluble sugar, total alkaloid, chloride and total nitrogen of tobacco reconstituted paper-base decreasing significantly after paper-making.

Tobacco stem and tobacco dust are the major raw materials in the reconstituted tobacco production. The extraction of the components from these materials is one of the most important procedures in making the reconstituted tobacco sheet. In this paper, we reported an approach of three-stage counter current extraction to transfer the components from tobacco stem and tobacco dust. The results showed that the extraction ratios for tobacco stem and tobacco dust were 40.2% and 54.2%, respectively. The testing results on the extracted tobacco stem and tobacco dust showed that the overall extraction ratios of water soluble sugars, total alkaloid, and chloride in tobacco dust were 89.3%, 90.5% and 100%, respectively; and the overall extraction ratios of water soluble sugars, total alkaloid and chloride in tobacco stem were 59.3%, 60.3% and 76.2%, respectively; The contents of total nitrogen in tobacco dust and tobacco stem were basically no change after each extraction. Lower extraction yield and higher extraction ration were obtain by three stages extract than those by single stage extract.

In this paper, the authors consider a class of bilinear pseudo-differential operators with symbols of order 0 and type (1, 0) in the sense of Hormander and use the atomic decompositions of local Hardy spaces to establish the boundedness of the bilinear pseudo-differential operators and the bilinear singular integral operators on the product of local Hardy spaces.

In this paper, we investigate the integration of the Hölder-Nikolskii classes in the randomized and quantum computation model. We develop randomized and quantum algorithms for integration of functions from this class and analyze their convergence rates. Comparing our result with the convergence rates in the deterministic setting, we see that quantum computing can reach an exponential speedup over deterministic classical computation and a quadratic speedup over randomized classical computation.

Fluorescent whitening agent is relatively small dosage in the coating, but it has great influence on the properties of the coating and ink-jet printing qualities. With the increase of fluorescent whitening agent dosage, the PH of the coating rose but the viscosity was hardly to change. The brightness of coated ink-jet printing paper and color density of the printing image firstly presented the trend of increasing then decreasing. What’s more, when the brightness of the coated paper achieved to the maximum, color density and contact angle properties were the largest. Chromatic aberration property of the image reduced from 1.87 to 1.75, when the addition of fluorescent whitening agent rose from 0.1% to 0.5%. While the dosage was rose to 0.9%, chromatic aberration increased to 2.15. The gloss of coated paper decreased with the dosage of fluorescent whitening agent increasing. In sum, fluorescent whitening agent can enhance the brightness of the coated paper as well as the printing properties. The results show that the best brightness and printing qualities of coated ink-jet printing paper are obtained, when the fluorescent whitening agent is 0.5%( relative to pigment).

This paper puts forward a method for a location system for colliery worker based on wireless mesh network combined with zigbee technology which supports IEEE 802.15.4 wireless communication standard, with low power dissipation. Data receipt and transmission by wireless communication is realized by RF chip MC13192 produced by Freescale company. Data procession and analysis is achieved by S3C2410A chip manufactured by Sumsung which belongs to ARM9 16/32 RISC processor.

The line parameters of the HITRAN 2004 have been updated, as compared with the older editions (the 2000 edition and the 1996 edition). In order to know the effect of the modifications on radiative transfer calculation with high spectral resolution, comparison in optical depth and radiance spectrum have been given between different editions. Four infrared spectral regions are selected, and they cover the three bands of atmospheric infrared sounder (AIRS) and one of geosynchronous imaging fourier transform spectrometer (GIFTS). The comparison has shown that the relative difference between HITRAN 2000 and 2004 and that between HITRAN 1996 and 2004 is decreasing. But the maximal discrepancy between the latest two editions in some spectral intervals is over 1%. It is important to estimate the error of calculation with the line parameters correctly or one has to use the new edition of HITRAN.

To understand the ecological impact of Spartina alterniflora on the coastal wetland environment, field survey was carried out in July, 2010, over the intertidal areas of Rudong coast, Jiangsu province; sediment samples were collected from a series of stations with different conditions of vegetation cover and S. alterniflora growth. The contents of eight heavy metals, together with sediment composition and total organic carbon were analyzed to reveal the distribution patterns of the heavy metals. Environmental quality status was evaluated using both the index of geoaccumulation (I(geo)) and the index of the Håkanson ecological risk. The analytical results showed that the average contents of Pb, Cd, As, Hg, Cr, Cu, Ni and Zn were below the standard for the Category I sediment quality, among which Cd, Hg, Ni and Zn exceeded the sediment background value of the region. On the whole, the contents of eight heavy metals in vegetation areas were higher than those associated with the adjacent bare flat areas. These data sets indicate a non-polluted condition in term of I(geo) estimation; however, a critical state of low to moderate degrees of pollution and a low level of risk were deduced according to the index of the Håkanson potential ecological risk. Both indices suggested that the pollution level of Hg and Cd were the highest among the eight metals measured. Along the transection from seaward to landward, the contents of As, Cu and Hg, their indices of I(geo) and Håkanson ecological risk all showed an increasing tread, in accordance with the condition of vegetation cover. Along the coastline with S. alterniflora being distributed in patchiness, all metal contents and their ecological risk level values for the marshes were higher than those for the unvegetated sediments nearby; moreover, except for Hg, other seven metals exhibited relatively low values than those in the shore-normal section with a better S. alterniflora growth. These findings indicate that S. alterniflora is one of important factors to enrich the heavy metal in tidal flat sediment. Thus, ecological risk of the heavy metal is reduced or blocked, due to the filtering effect of salt-marsh, which prevents metals from entering the open sea directly. The distribution of heavy metal is influenced by a combination of colonization time of vegetation, chemical form of metals and their origins.

Three rare earth coordination polymers, {[Ln2(μ3-ADI)2(μ2-ADI)(H2O)4]·H2O}n (Ln = Tb, 1; Eu, 2; Er, 3; ADI = adipate), which show the inclined interpenetration of (4, 4) nets and bright luminescence, were isolated from H2PDC-assisted (H2PDC = pyridine-2,3-dicarboxylatic acid) hydrothermal reactions of H2ADI and Ln2O3.

A 3D coordination polymer, {[Cd15(μ4-Mtta)12(μ3-Mtta)6(μ3-SO4)4(μ3-OH)4] · 6H2O}n (1) (Mtta = 5-methyl-tetrazolate), which shows the rare multifunction of in situ formed Mtta and bright photo-induced blue emission, was isolated from a hydrothermal reaction of CdSO4 · 8/3H2O, NaN3 in acetonitrile and water.

To explore the role of HIV-1 tat gene variations in AIDS dementia complex (ADC) pathogenesis.HIV-1 tat genes derived from peripheral spleen and central basal ganglia of an AIDS patient with ADC and an AIDS patient without ADC were cloned for sequence analysis. HIV-1 tat gene sequence alignment was performed by using CLUSTAL W and the phylogentic analysis was conducted by using Neighbor-joining with MEGA4 software. All tat genes were used to construct recombinant retroviral expressing vector MSCV-IRES-GFP/tat. The MSCV-IRES-GFP/tat was cotransfected into 293T cells with pCMV-VSV-G and pUMVC vectors to assemble the recombinant retrovirus. After infection of gliomas U87 cells with equal amount of the recombinant retrovirus, TNF-α, and IL-1β concentrations in the supernatant of U87 cells were determined with ELISA.HIV-1 tat genes derived from peripheral spleen and central basal ganglia of the AIDS patient with ADC and the other one without ADC exhibited genetic variations. Tat variations and amino acid mutation sites existed mainly at Tat protein core functional area (38-47aa). All Tat proteins could induce U87 cells to produce TNF-α and IL-1β, but the level of IL-1β production was different among Tat proteins derived from the ADC patient's spleen, basal ganglia, and the non-ADC patient's spleen. The level of Tat proteins derived from the ADC patient's spleen, basal ganglia, and the non-ADC patient's spleen were obviously higher than that from the non-ADC patient's basal ganglia.Tat protein core functional area (38-47aa) may serve as the key area of enhancing the secretion of IL-1β. This may be related with the neurotoxicity of HIV-1 Tat.

Intertidal flats represent a typical environmentally fragile and sensitive zone. In order to investigate the environmental quality of the intertidal zone in Luoyuan Bay, field survey was carried out in 2009. Contents of heavy metals (Co, Cr, Cu, Ni, Pb, V and Zn) in the surficial sediment were measured using an inductively coupled plasma optical emission spectrometer (ICP-OES). Moreover, the impact on the environment quality was evaluated with the potential ecological risk method. The average contents of the heavy metals Co, Cr, Cu, Ni, Pb, V and Zn in the surficial sediment were 20.48, 77.82, 23.24, 40.67, 36.25, 134.75 and 111.21 mg x kg(-1), respectively. The heavy metal contents in the Spartina alterniflora salt-marsh were apparently higher than those in the bare flat. Further, the heavy metal concentrations found in the present study were generally higher than the background values of the coastal regions of Fujian Province, but lower than those associated with the Pearl River estuary. According to principal component and correlation analyses, industrial wastewater, mineral exploration and degradation of organic matter were the main sources of heavy metals in the area investigated. The results of potential ecological risk evaluation indicated that the intertidal zone as a whole can be ranked as "moderate potential ecological risk". Ni and Co were the major pollutants among the metals in consideration; the pollution related to Pb was less significant. The level of potential ecological risk of the Spartina alterniflora slat-marsh was higher than that of the bare flat. The sequence of potential ecological risk for the heavy metals was NiCoCuPbCrVZn.

The robust stability problem for nonlinear distributed delay stochastic systems with polytopic-type uncertainties is discussed. Based on parameter-dependent Lyapunov-krasovs-kii functional and free-weighting matrix method, a delay-dependent and parameter-dependent stability condition is presented in terms of linear matrix inequalities. The result in this paper improves the existing stability criteria and has less conservativeness. The simulation example shows that the result is effective.

Headspace solid-phase microextraction HS-SPME) technique was employed to extract the volatile compounds from Pollen Pini. The volatile components were isolated and identified successfully by gas chromatography-mass spectrometry (GC-MS). The volatiles were collected using several SPME parameters (including extraction time and temperature). The best response was obtained using a PA fiber by when the extraction temperature was 70 degrees C, extraction time was 30 minutes and desorption time was 10 time. Analysis was performed by GC-MS. Seventy components were identified by HS-SPME. The main components were fatty compounds. The results showed that the HS-SPME technique could be used to extract the volatile components from HS-SPME-GC-MS.

A simple and highly sensitive new kinetic catalytic fluorimetric method was proposed for the determination of trace chromium (VI), based on the catalytic effect of trace amounts of chromium (VI) on the oxidation of Pyronine Y by hydrogen peroxide in acetic acid-sodium acetate buffer medium leading to a decrease in the fluorescence intensity. The optimum conditions and kinetic properties of the catalytic reaction were also studied. The apparent activation energy and the apparent rate constant are 159. 92 k * x mol(-1) and 5. 7X10-2 s-1 respectively. The linear range of the calibration curve is 0. 02-0. 24 microg x mL(-1) and the detection limit is 0. 012 microg x mL(-1). The present method was applied to the determination of chromium(VI) in river water, and industrial and electroplating waste water with good results.

A simple, rapid, reproducible, and universal non-aqueous capillary electrophoresis method has been developed for the separation and determination of three major active protoberberine alkaloids including berberine, palmatine, and jatrorrhizine within 7 min. The effects of the concentrations of acetic acid and electrolyte, the ratio of organic solvent, and the applied voltage on the separation were investigated. The optimum running buffer was composed of 50 mM ammonium acetate, 0.5% (v/v) acetic acid, and 10% (v/v) acetonitrile in methanol. The applied voltage was 18 kV. The analytes were detected by UV at 214 nm. The linearities between peak areas and the concentrations of the analytes were also investigated, and they exhibit excellent linear behavior over the concentration ranges (correlation coefficients: 0.9975-0.9986). The method was successfully applied to determine the three alkaloids in several families of herbal drugs (Rhizoma Coptidis, Cortex Berberidis, Cortex Phellodendri, Herba Chelidonii, Caulis Mahoniae) and their relevant medicinal preparations for the first time, and the recoveries of the three constituents ranged between 95.6-103.2% for berberine, 97.5-103.3% for palmatine, and 96.1 -103.6% for jatrorrhizine.