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Studies on surface wettability have received tremendous interest due to their potential applications in research and industrial processes. One of the strategies to tune surface wettability is modifying surface topography at micro- and nanoscales. In this research, periodic micro- and nanostructures were patterned on several polymer surfaces by ultra-precision single point diamond turning to investigate the relationships between surface topographies at the micro- and nanoscales and their surface wettability. This research revealed that single-point diamond turning could be used to enhance the wettability of a variety of polymers, including polyvinyl chloride (PVC), polyethylene 1000 (PE1000), polypropylene copolymer (PP) and polytetrafluoroethylene (PFTE), which cannot be processed by conventional semiconductor-based manufacturing processes. Materials exhibiting common wettability properties (θ ≈ 90°) changed to exhibit “superhydrophobic” behavior (θ ˃ 150°). Compared with the size of the structures, the aspect ratio of the void space between micro- and nanostructures has a strong impact on surface wettability. Keywords: Contact angle, Wettability, Single-point diamond turning, Structured surface, Hydrophobicity

The deposition of insoluble light-absorbing particles (ILAPs) on snow and ice surfaces can significantly reduce albedo, thereby accelerating the melting process. In this study, 67 ice samples were collected from seven glaciers located on the Tibetan Plateau (TP) between May 2013 and October 2015. The mixing ratios of black carbon (BC), organic carbon (OC), and mineral dust (MD) were measured with an integrating sphere/integrating sandwich spectrophotometer (ISSW) system, which assumes that the light absorption of MD is due to iron oxide (Fe). Our results indicate that the mass-mixing ratios of BC, OC, and Fe exhibit considerable variability (BC: 10–3100 ng g−1; OC: 10–17 000 ng g−1; Fe: 10–3500 ng g−1) with respective mean values of 220±400 ng g−1, 1360±2420 ng g−1, and 240±450 ng g−1 over the course of the field campaign. We observed that for wavelengths of 450–600 nm, the measured light absorption can be largely attributed to the average light absorption of BC (50.7 %) and OC (33.2 %). Chemical elements and selected carbonaceous particles were also analyzed for source attributions of particulate light absorption based on a positive matrix factorization (PMF) receptor model. Our findings indicate that on average, industrial pollution (33.1 %), biomass or biofuel burning (29.4 %), and MD (37.5 %) constitute the principal sources of ILAPs deposited on TP glaciers.

The emerging computable devices, graphical processing units (GPUs), are gradually applied in the simulations of space physics. In this paper, we introduce an approach that implements full kinetic particle-in-cell simulations on GPU architecture devices using the CUDA Fortran language programming for the first time. Using the latest high-performance computing NVIDIA GPUs, this program, which follows the second-order leap-frog iteration method, can speed up the computing process by a factor of 150–285 on a single device compared with the time cost of running with a single core of an Intel Xeon Gold processor. Our scheme improves fast accessibility to the simulation results and provides valuable assistance in studying the physical process.

The black carbon (BC) deposition on the ice core at Muztagh Ata Mountain, northern Tibetan Plateau, was analyzed. Two sets of measurements were used in this study, which included the air samplings of BC particles during 2004–2006 and the ice core drillings of BC deposition during 1986–1994. Two numerical models were used to analyze the measured data. A global chemical transportation model (MOZART-4) was used to analyze the BC transport from the source regions, and a radiative transfer model (SNICAR) was used to study the effect of BC on snow albedo. The results show that during 1991–1992, there was a strong spike in the BC deposition at Muztagh Ata, suggesting that there was an unusual emission in the upward region during this period. This high peak of BC deposition was investigated by using the global chemical transportation model (MOZART-4). The analysis indicated that the emissions from large Kuwait fires at the end of the first Gulf War in 1991 caused this high peak of the BC concentrations and deposition (about 3–4 times higher than other years) at Muztagh Ata Mountain, suggesting that the upward BC emissions had important impacts on this remote site located on the northern Tibetan Plateau. Thus, there is a need to quantitatively estimate the effect of surrounding emissions on the BC concentrations on the northern Tibetan Plateau. In this study, a sensitivity study with four individual BC emission regions (Central Asia, Europe, the Persian Gulf, and South Asia) was conducted by using the MOZART-4 model. The result suggests that during the normal period (non-Kuwait fires), the largest effect was due to the Central Asia source (44 %) during the Indian monsoon period, while during the non-monsoon period, the largest effect was due to the South Asia source (34 %). The increase in radiative forcing increase (RFI) due to the deposition of BC on snow was estimated by using the radiative transfer model (SNICAR). The results show that under the fresh snow assumption, the estimated increase in RFI ranged from 0.2 to 2.5 W m−2, while under the aged snow assumption, the estimated increase in RFI ranged from 0.9 to 5.7 W m−2. During the Kuwait fires period, the RFI values increased about 2–5 times higher than in the normal period, suggesting a significant increase for the snow melting on the northern Tibetan Plateau due to this fire event. This result suggests that the variability of BC deposition at Muztagh Ata Mountain provides useful information to study the effect of the upward BC emissions on environmental and climate issues in the northern Tibetan Plateau. The radiative effect of BC deposition on the snow melting provides important information regarding the water resources in the region.

Brassinosteroids (Brs) have drawn wide attention due to their protective role against toxicity of heavy metals in plants. To better understand the role of Br in arsenic (As) and cadmium (Cd) uptake by rice plants, a hydroponic experiment was conducted to investigate the combined effect of 24-epibrassinolide (Br24) or 28-homobrassinolide (Br28) and iron plaque (IP) on As and Cd uptake and accumulation in rice seedlings. Six-week-old seedlings were sprayed with 0.2 or 0.02 μM Br24 or Br28 and grown in nutrient solution for 3 d, and then 20 or 60 mg Fe2+ dm-3 (Fe20 and Fe60) was used to induce root IP formation for 3 d. These seedlings with or without Br and with or without IP were exposed to solution containing 0.5 mg dm-3 AsIII or Cd for 9 d. The results showed that rice growth decreased when Br24 were applied, but it increased when combination of Br24 and IP was applied. Fe concentrations in dithionite-citratebicarbonate (DCB) extracts were increased after 0.2 or 0.02 μM Br24 application in the absence of IP, but decreased by Br24 in the presence of IP. In the absence of IP, As and Cd content in leaves was significantly reduced by 0.02 μM Br24 and 0.2 μM Br28, respectively. The As content in leaves was also reduced by the combination of 0.02 and 0.2 μM Br28 and IP, and the Cd content in leaves was reduced by the combined effect of 0.2 μM Br24 and IP. These results indicate that Br24 and Br28 could impede As and Cd accumulation, and the interactions between Br and IP may have a potential in restricting the transport of As and Cd into rice shoots.

The accurate positioning of optical satellite image without control is the precondition for remote sensing application and small/medium scale mapping in large abroad areas or with large-scale images. In this paper, aiming at the geometric features of optical satellite image, based on a widely used optimization method of constraint problem which is called Alternating Direction Method of Multipliers (ADMM) and RFM least-squares block adjustment, we propose a GCP independent block adjustment method for the large-scale domestic high resolution optical satellite image – GISIBA (GCP-Independent Satellite Imagery Block Adjustment), which is easy to parallelize and highly efficient. In this method, the virtual "average" control points are built to solve the rank defect problem and qualitative and quantitative analysis in block adjustment without control. The test results prove that the horizontal and vertical accuracy of multi-covered and multi-temporal satellite images are better than 10 m and 6 m. Meanwhile the mosaic problem of the adjacent areas in large area DOM production can be solved if the public geographic information data is introduced as horizontal and vertical constraints in the block adjustment process. Finally, through the experiments by using GF-1 and ZY-3 satellite images over several typical test areas, the reliability, accuracy and performance of our developed procedure will be presented and studied in this paper.

In this paper, we tried to reveal the characteristics of the crustal deformation in both the horizontal and vertical directions in Beijing using InSAR and GNSS observations. Regarding the serious land subsidence in Beijing plain, we also analysed the mechanism of the occurrence and development of the subsidence in combination with the tectonic settings. The GNSS results reveal that the crust in Beijing shows a significant left-lateral trend movement in the horizontal direction, while the vertical direction shows a gentle rise in the mountainous region and a significant subsidence in the plain area. The INSAR results shows a detailed subsidence area and the deformation characteristics were analyzed considering the fault activity. The foundation of geological structure dominates the subsiding in the Beijing Plain. The exploitation of groundwater exacerbates the level of subsidence and has new development. The active faults controlled the development of the subsiding in present days.

With frequent air pollution episodes in China, growing research emphasis has been put on quantifying meteorological influences on PM2.5 concentrations. However, these studies mainly focus on isolated cities, whilst meteorological influences on PM2.5 concentrations at the national scale have not yet been examined comprehensively. This research employs the CCM (convergent cross-mapping) method to understand the influence of individual meteorological factors on local PM2.5 concentrations in 188 monitoring cities across China. Results indicate that meteorological influences on PM2.5 concentrations have notable seasonal and regional variations. For the heavily polluted North China region, when PM2.5 concentrations are high, meteorological influences on PM2.5 concentrations are strong. The dominant meteorological influence for PM2.5 concentrations varies across locations and demonstrates regional similarities. For the most polluted winter, the dominant meteorological driver for local PM2.5 concentrations is mainly the wind within the North China region, whilst precipitation is the dominant meteorological influence for most coastal regions. At the national scale, the influence of temperature, humidity and wind on PM2.5 concentrations is much larger than that of other meteorological factors. Amongst eight factors, temperature exerts the strongest and most stable influence on national PM2.5 concentrations in all seasons. Due to notable temporal and spatial differences in meteorological influences on local PM2.5 concentrations, this research suggests pertinent environmental projects for air quality improvement should be designed accordingly for specific regions.

Soil microbial activity varies seasonally in frozen alpine soils during cold seasons and plays a crucial role in available N pool accumulation in soil. The intra- and interannual patterns of microbial and nutrient dynamics reflect the influences of changing weather factors, and thus provide important insights into the biogeochemical cycles and ecological functions of ecosystems. We documented the seasonal and interannual dynamics of soil microbial and available N in an alpine meadow in the eastern part of Qinghai–Tibet Plateau, China, between April 2011 and October 2013. Soil was collected in the middle of each month and analyzed for water content, microbial biomass C (MBC) and N (MBN), dissolved organic C and N, and inorganic N. Soil microbial community composition was measured by the dilution-plate method. Fungi and actinomycetes dominated the microbial community during the nongrowing seasons, and the proportion of bacteria increased considerably during the early growing seasons. Trends of consistently increasing MBC and available N pools were observed during the nongrowing seasons. MBC sharply declined during soil thaw and was accompanied by a peak in available N pool. Induced by changes in soil temperatures, significant shifts in the structures and functions of microbial communities were observed during the winter–spring transition and largely contributed to microbial reduction. The divergent seasonal dynamics of different N forms showed a complementary nutrient supply pattern during the growing season. Similarities between the interannual dynamics of microbial biomass and available N pools were observed, and soil temperature and water conditions were the primary environmental factors driving interannual fluctuations. Owing to the changes in climate, seasonal soil microbial activities and nutrient supply patterns are expected to change further, and these changes may have crucial implications for the productivity and biodiversity of alpine ecosystems.

In this paper, the gradient temperature rolling (GTR) method is used to establish the 12-pass rolling model by Deform- 3D finite element (FE) software. The variation of temperature field and strain field of ultra-heavy plate slab under different conditions is systematically studied. The result shows that the more the number of water cooling between the passes during the rolling process, the greater the deformation of the core of slab, and the one of plate rolling with large temperature difference does not appear on near surface but gradually moves to the central part of the plate as cooling times increase.

Background. Gymnocypris firmispinatus Wu et Wu, 1988 is a small fish with the maximum total length of 242 mm, which occurs only in the Jinsha River and its tributaries (China), at altitudes above 2000 m. Nowadays, G. firmispinatus had been placed in a dangerous situation, due to hydropower station and excessive fishing. However, attempts to develop an effective population management strategy have been obstructed by lack of basic biological information, especially for age estimation. As we known, sectioned otoliths provide the most precise age estimates of many Schizothoracinae fishes, vertebrae and opercular bones were also used for age determination of some fish species. This work aimed to assess the suitability of three calcified structures (otolith, vertebra, and opercular bone) for age estimation of G. firmispinatus. Materials and methods. The annulus characteristics of otolith, vertebra, and opercular bone were described. Annual periodicity was verified by marginal increment ratio (MIR) analysis in otoliths and edge analysis in vertebrae and opercular bones. Otoliths, vertebrae, and opercular bones were examined to determine which structure produced the most precise and accurate age estimates in G. firmispinatus, mainly by scoring for readability on a five-point scale and calculating the index of the mean percentage error (IMPE). Results. Microscopically, otoliths and vertebrae showed a typical pattern of opaque-and translucent-zones, attributed to slow and fast growth periods. Annuli formed between March and May once a year in otoliths and vertebrae. Forty-four percent of the opercular bones were scored as unreadable. The value of IMPE between the two counts was lowest for otoliths (4.25%), followed by vertebrae (6.21%) and opercular bones (11.58%). The IMPE value of vertebra vs. otolith was 11.05%, while that of opercular bone vs. otolith was 23.03%. Vertebrae and otoliths matched closely only for the first 4 years of life, while opercular bones appeared to underestimate the age of G. firmispinatus. Conclusion. Annuli in the otoliths and vertebrae both formed once a year up to age 8, and otoliths would be the most precise structure for age determination in G. firmispinatus. Vertebrae and otoliths matched closely up to age 4, while opercular bones could not be used for age estimation for the species.

Abstract Engineering of novel functional nanocomposite as like as the metallic nanocrystals supported non-stoichiometric perovskite nanomaterial in controlled parameters (size, shape and ratio of chemical characteristics) is a challengeable task. In this context, we present a facile route to fabricate and study its physicochemical property at real time mode in this report. Nanoscale pure Pb crystals surfaced on non-stoichiometric A-site deficient Pb1-xTiO3-y nanoparticle were fabricated when a precursor lead titanate (PbTiO3) nanoparticle was exposed to an electron beam irradiation (EBI) in a transmission electron microscope (TEM) at ambient temperature. In the state of the art, the chemical states and electronic structure of non-irradiated and irradiated PbTiO3 were studied by X-ray photoelectron spectroscopy (XPS). Electron bombardment resulted in a new visible feature at low binding energy in the Pb 4f core level, while Ti 2p and O 1s line shape showed slight changes. The Fermi level of the corresponding materials was determined to be 1.65 ± 0.1 eV and 2.05 ± 0.1 eV above the valence band maximum, respectively. The normal, weakly p-type PTO exhibits peculiar n-type feature after EBI process (The Fermi level moves near to the conduction band). A feasible mechanism is proposed involving the electron-stimulated local bond-breaking phenomenon in PbTiO3.

Stylistic layers presented in the structure of the lexico-phraseological field (LPF) “Literature” in the modern Russian language are considered. It is noted that this field includes a set of lexical and phraseological units, united thematically and semantically by attitude to art literature as activity and result of this activity. It is shown that the LPF “Literature” is a field of terminology type, which vocabulary is based on the terms of the relevant sector, that makes its specificity, including stylistic. Thus LPF has a complex stylistic structure. The author identifies common words ( writer ) and special terms ( litotes ) in the terminological part of the LPF. It is noted that non-terminological vocabulary can have a conversational connotation, expressing a mocking, ironic, dismissive attitude of the speaker to the literary work ( stuffer ), and high connotation including archaic words ( master of word ). Novelty of research consists in the fact that an intermediate position between these completely different stylistic layers of professionalisms used in casual conversational speech of people who are related to literary activities are analyzed. It is shown that the tokens and phrasemes can change their stylistic connotation and move from one layer to another. It is concluded that stylistic diversity indicates high activity use of the units of LPF “Literature” in various spheres of human activity.

Understanding the factors that determine the properties of permanent magnets, which play a central role in many industrial applications, can help in improving their performance. Here, the authors study how changes in the iron content affect the microstructure of samarium cobalt magnets.

Abstract The charge-trapping memory devices with a structure Pt/Al2O3/(Ta2O5) x (TiO2) 1−x /Al2O3/p-Si (x = 0.9, 0.75, 0.5, 0.25) were fabricated by using rf-sputtering and atomic layer deposition techniques. A special band alignment between (Ta2O5) x (TiO2) 1−x and Si substrate was designed to enhance the memory performance by controlling the composition and dielectric constant of the charge-trapping layer and reducing the difference of the potentials at the bottom of the conduction band between (Ta2O5) x (TiO2) 1−x and Si substrate. The memory device with a composite charge storage layer (Ta2O5) 0.5 (TiO2) 0.5 shows a density of trapped charges 3.84 × 1013/cm2 at ± 12 V, a programming/erasing speed of 1 µs at ± 10 V, a 8% degradation of the memory window at ± 10 V after 104 programming/erasing cycles and a 32% losing of trapped charges after ten years. The difference among the activation energies of the trapped electrons in (Ta2O5) x (TiO2) 1−x CTM devices indicates that the retention characteristics are dominated by the difference of energy level for the trap sites in each TTO CTM device.

Abstract The Compact Linear Collider (CLIC) is an option for a future $${\mathrm{e}^{+}}{\mathrm{e}^{-}} $$ e + e - collider operating at centre-of-mass energies up to $$3\,\text {TeV} $$ 3 TeV , providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper is the first comprehensive presentation of the Higgs physics reach of CLIC operating at three energy stages: $$\sqrt{s} = 350\,\text {GeV} $$ s = 350 GeV , 1.4 and $$3\,\text {TeV} $$ 3 TeV . The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung ( $${\mathrm{e}^{+}}{\mathrm{e}^{-}} \rightarrow {\mathrm{Z}} {\mathrm{H}} $$ e + e - → Z H ) and $${\mathrm{W}} {\mathrm{W}} $$ W W -fusion ( $${\mathrm{e}^{+}}{\mathrm{e}^{-}} \rightarrow {\mathrm{H}} {{\nu }}_{\!\mathrm{e}} {\bar{{\nu }}}_{\!\mathrm{e}} $$ e + e - → H ν e ν ¯ e ), resulting in precise measurements of the production cross sections, the Higgs total decay width $$\varGamma _{{\mathrm{H}}}$$ Γ H , and model-independent determinations of the Higgs couplings. Operation at $$\sqrt{s} > 1\,\text {TeV} $$ s > 1 TeV provides high-statistics samples of Higgs bosons produced through $${\mathrm{W}} {\mathrm{W}} $$ W W -fusion, enabling tight constraints on the Higgs boson couplings. Studies of the rarer processes $${\mathrm{e}^{+}}{\mathrm{e}^{-}} \rightarrow \mathrm{t} {\bar{\mathrm{t}}} {\mathrm{H}} $$ e + e - → t t ¯ H and $${\mathrm{e}^{+}}{\mathrm{e}^{-}} \rightarrow {\mathrm{H}} {\mathrm{H}} {{\nu }}_{\!\mathrm{e}} {\bar{{\nu }}}_{\!\mathrm{e}} $$ e + e - → H H ν e ν ¯ e allow measurements of the top Yukawa coupling and the Higgs boson self-coupling. This paper presents detailed studies of the precision achievable with Higgs measurements at CLIC and describes the interpretation of these measurements in a global fit.

The study of lattice vibrations coupled to electronic excitations may provide an avenue for exploring exotic physical phenomena. Here, Xuet al. observe a Fano resonance in the Weyl semimetal TaAs, revealing evidence for a strong coupling between phonons and Weyl fermions.

Background: We conducted a meta-analysis of published literature to identify the correlation between leptin receptor gene polymorphisms and the risk of obstructive sleep apnea syndrome (OSAS). Methods: Five different single nucleotide polymorphisms (SNPs) were studied. Only Gln223Arg and Pro1019Pro had multiple studies. Nine studies focused on the correlation between Gln223Arg and Pro1019Pro polymorphisms and OSAS risk. Fixed-effects model or random-effects model was used to calculate the pooled odds ratio (ORs) and its corresponding 95% confidence interval (95% CI). The Begg's, Egger's, Perter's and Harbord tests were used to measure publication bias. Sensitivity analysis was also performed to ensure the robustness of the findings. Results: Six studies on Gln223Arg polymorphisms (661 cases and 498 controls) and three studies on Pro1019Pro polymorphisms (561 cases and 561 controls) were extracted. There was no correlation between the leptin receptor Gln223Arg polymorphism and the risk of OSAS (odd ratio = 0.86, 95% CI = 0.68â1.10, P = 0.23). However, Caucasian OSAS patients had a higher Arg allele frequency; whereas Chinese population with G genotype were more susceptible to OSAS (odd ratio = 1.28, 95% CI = 1.04â1.57, P = 0.02) in the studies on Pro1019Pro polymorphisms. Conclusion: The Gln223Arg polymorphisms in the Caucasian population and the Pro1019Pro polymorphisms in the Chinese population are risk factors for OSAS. Keywords: Leptin receptor gene polymorphism, rs1137101, Obstructive sleep apnea syndrome, Risk, Meta-analysis

Serine proteases play central roles in immune defense in invertebrates through innate immunity, and are particularly important complement system in molluscs because their susceptibility to infection due to lack of an adaptive immune ability. A gene encoding the serine protease homolog from the triangle - shell pearl mussel (Hyriopsis cumingii) was identified and designated as HC-SPH in this study. Protein sequence analysis revealed that HC-SPH consists of a typical Tryp_SPc functional domain of serine protease of S1 family lead by a signal peptide, and the molecule shares a highly conserved sequence and structural organization with other members, including a cleavage site, 3 enzymatic active sites and 3 substrate binding sites, so that it was clustered into a trypsin-like serine protease subfamily of the S1 superfamily. Semi - quantitative analysis of the amplicons separated on agarose gel by comparing to the β-actin products revealed that the digestive gland had a strong expression while the gonads were seen as weak expression sites. Infected by Aeromonas hydrophila, the gene expression was significantly up - regulated in the kidney at the 6 hours post challenge (hpc), stomach at 12 hpc and gills at 24 hpc while the expression maintained steadily unchanged in the digestive gland. However, up to 48 hpc, the expression levels in all four tissues reached significantly high, and also joined by a high level of expression in intestine that was down - regulated before 24 hpc, to build up an enhanced immune defense. The complementary up - regulation of the gene expression in these tissues suggested a temporal and spatial reinforce model for HC-SPH in immune response.

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.

Litters of reproductive organs have rarely been studied despite their role in allocating nutrients for offspring reproduction. This study determines the mechanism through which flower litters efficiently increase the available soil nutrient pool. Field experiments were conducted to collect plant litters and calculate biomass production in an alpine meadow of the eastern Tibetan Plateau. C, N, P, lignin, cellulose content, and their relevant ratios of litters were analyzed to identify their decomposition features. A pot experiment was performed to determine the effects of litter addition on the soil nutrition pool by comparing the treated and control samples. The litter-bag method was used to verify decomposition rates. The flower litters of phanerophyte plants were comparable with non-flower litters. Biomass partitioning of other herbaceous species accounted for 10–40 % of the aboveground biomass. Flower litter possessed significantly higher N and P levels but less C ∕ N, N ∕ P, lignin ∕ N, and lignin and cellulose concentrations than leaf litter. The litter-bag experiment confirmed that the flower litters of Rhododendron przewalskii and Meconopsis integrifolia decompose approximately 3 times faster than mixed litters within 50 days. Pot experiment findings indicated that flower litter addition significantly increased the available nutrient pool and soil microbial productivity. The time of litter fall significantly influenced soil available N and P, and soil microbial biomass. Flower litters fed the soil nutrition pool and influenced nutrition cycling in alpine ecosystems more efficiently because of their non-ignorable production, faster decomposition rate, and higher nutrient contents compared with non-flower litters. The underlying mechanism can enrich nutrients, which return to the soil, and non-structural carbohydrates, which feed and enhance the transitions of soil microorganisms.

In this paper, we propose a new solution to the low RFM fitting precision caused by exposure time changing using sensor correction. First, we establish a new rigorous geometric model, with the same ephemerides, attitudes and sensor design parameters of Chang’E-2 and HRSC images, using an equal exposure time of each scan line. The original rigorous geometric model is also established. With a given height, we can establish the correspondence between the two rigorous models. Then we generate a sensor corrected image by resampling the original image using an average elevation or a digital elevation model. We found that the sensor corrected images can be used for topographic mapping which maintains almost the same precision of the original images under certain conditions. And RFM can fit rigorous geometric model of the sensor corrected image very well. Preliminary experimental results show that the RMS residual error of the RFM fitting can reach to 1/100 pixel level too. Using the proposed solution, sensors with changing exposure time can be precisely modelled by the generic RFM.

This study brings together plot-scale growing season fluxes of carbon dioxide (CO2) and methane (CH4) from six Canadian peatlands restored by the moss layer transfer technique (MLTT) and compares them with fluxes from adjacent unrestored and natural peatlands to determine: 1) if CO2 and CH4 fluxes return to natural-site levels and 2) whether the ecohydrological controls (e.g. water table, plant cover) on these fluxes are similar between treatments. We also examine differences between eastern (humid/maritime climate) and western (sub-humid climate) Canadian plots, and between restoration of former horticultural peat extraction sites and oil industry well-pads. Our results indicate that restored site fluxes of CO2 and CH4 are not significantly different between eastern and western Canada or between a restored well-pad and restored horticultural peat extraction sites. Restoration resulted in gross primary production rates similar to those at natural plots and significantly greater than those at unrestored plots. Ecosystem respiration was not significantly different at restored and unrestored plots, and was lower at both than at natural plots. Methane emission was significantly greater at restored plots than at unrestored plots, but remained significantly lower on average than at natural plots. Water table was a significant control on CH4 flux across restored and natural plots. Vascular plant cover was significantly related to CO2 uptake (gross photosynthesis) at restored and unrestored plots, but not at natural plots, while higher moss cover resulted in significantly greater net uptake of CO2 at natural plots but not at restored and unrestored plots. Overall, MLTT restoration greatly alters CO2 and CH4 dynamics compared to unrestored areas but fluxes remain, on average, significantly different from those in natural peatlands, in both the magnitude of mean growing season fluxes and controls on variation in these fluxes among plots. Peatland restoration by MLTT results in reduced CO2 emissions and higher CH4 emissions; however, more year-round measurements in more restored peatlands over longer periods post-restoration are needed to improve greenhouse gas emission estimates for restored Canadian peatlands.

This paper presents an empirical analysis of the geopositioning precision of multiple image triangulation using Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images at the Chang’e-3(CE-3) landing site. Nine LROC NAC images are selected for comparative analysis of geopositioning precision. Rigorous sensor models of the images are established based on collinearity equations with interior and exterior orientation elements retrieved from the corresponding SPICE kernels. Rational polynomial coefficients (RPCs) of each image are derived by least squares fitting using vast number of virtual control points generated according to rigorous sensor models. Experiments of different combinations of images are performed for comparisons. The results demonstrate that the plane coordinates can achieve a precision of 0.54 m to 2.54 m, with a height precision of 0.71 m to 8.16 m when only two images are used for three-dimensional triangulation. There is a general trend that the geopositioning precision, especially the height precision, is improved with the convergent angle of the two images increasing from several degrees to about 50°. However, the image matching precision should also be taken into consideration when choosing image pairs for triangulation. The precisions of using all the 9 images are 0.60 m, 0.50 m, 1.23 m in along-track, cross-track, and height directions, which are better than most combinations of two or more images. However, triangulation with selected fewer images could produce better precision than that using all the images.

With terahertz and infrared spectroscopy we studied the in-plane response of an underdoped, twinned YBa_{2}Cu_{3}O_{6.6} single crystal with T_{c}=58(1)K in high magnetic fields up to B=30 Tesla (T) applied along the c axis. Our goal was to investigate the field-induced suppression of superconductivity and to observe the signatures of the three-dimensional (3D) incommensurate copper charge density wave (Cu-CDW), which was previously shown to develop at such high magnetic fields. Our study confirms that a B field in excess of 20 T gives rise to a full suppression of the macroscopic response of the superconducting condensate. However, it reveals surprisingly weak signatures of the 3D Cu-CDW at high magnetic fields. At 30 T there is only a weak reduction of the spectral weight of the Drude-response (by about 3%), which is accompanied by an enhancement of the so-called mid-infrared (MIR) band as well as a narrow electronic mode around 240cm^{−1} (and, possibly, another one around 90cm^{−1}), which is interpreted in terms of a pinned phase mode of the CDW. The pinned phase mode and the MIR band are strong features already without magnetic field, which suggests that prominent but short-ranged and slowly fluctuating (compared to the picosecond infrared timescale) CDW correlations exist all along, i.e., even at zero magnetic field.