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The genus Microichthyurus Pic 1919 is first recorded here from mainland China. Four new species are described: M. flavicollis sp. nov. (China, Guizhou), M. villosipes sp. nov. (China, Chongqing), M. hubeiensis sp. nov. (China, Hubei) and M. elongatus sp. nov. (China, Yunnan). These new species are illustrated with habitus and genital segments of both sexes, and aedeagi and internal genitalia of females. The generic diagnosis is summarized and an identification key to all Chinese Microichthyurus species is provided.

The working fluids at supercritical pressures will experience abnormal heat transfer compared with those in a sub-critical state. In particular, the heat transfer deterioration (HTD) can make the wall temperature increase sharply in the tube, posing a challenge for the design of heat exchangers in the supercritical organic Rankine cycle (SORC). It is generally acknowledged that the effects of buoyancy and flow acceleration lead to abnormal heat transfer. However, a clear understanding of the interactions between the turbulent flow and heat transfer characteristics still needs to be further improved by obtaining the internal flow mechanism. The current study analyses the contours of the turbulent flow information under the different boundary conditions by means of validated CFD numerical simulation based on the previous experimental data and reveals the main causes of HTD and the impact mechanism of boundary conditions. The results reveal that two deteriorated extreme points are generated in a vertical upward tube with uniform heat flux for hexamethyldisiloxane at supercritical pressures. The buoyancy and flow acceleration effects caused by the drastic variation in fluid density near the pseudo-critical temperature can deform the velocity profile, thus reducing the local shear stress and turbulence intensity, and leading to the HTD. Moreover, HTD gets worse with the increase in heat flux and moderate with the rise in supercritical pressure. This study should support the data and theory for the refined design of heaters applied to the SORC in the future.

Over recent years, the utilization of commercially available integrated navigation systems for the development of navigation algorithms has become increasingly commonplace. Nevertheless, the wide range of sensor quality on the market complicates system customization and restricts the evolution of navigation algorithms. This study aims to address these issues by creating an affordable, tactical-grade, real-time integrated navigation system, EGI-500 (Embedded GNSS and INS), encompassing both hardware and software components. EGI-500 incorporates a tactical-grade IMU500 and a Septentrio Mosaic-X5 GNSS receiver module. The integration process is segmented into three distinct stages. The first involves hardware integration, with an illustrative architecture diagram of the real-time navigation system. Second, we focus on data preprocessing, where a cross-correlation approach is proposed to tackle multi-sensor time synchronization issues, specifically to determine potential time lags in IMU data. The final phase covers the fusion of multi-sensor data and motion constraints. The Extended Kalman Filter (EKF) forms the backbone of this part, with Zero Velocity Update (ZUPT) and Non-Holonomic Constraints (NHC) being integrated into the Loosely Coupled (LC) scheme. Furthermore, the IMU calibration process is performed to ascertain necessary algorithmic parameters. Experimental results, conducted in diverse environments (open sky, GNSS challenging, and GNSS denied), will be presented in this paper. Comparisons with reference data indicate that the navigation accuracy of the developed integrated system, both in terms of hardware and navigation algorithm, achieves expected meter-level accuracy, fulfilling the "Which Lane" and "Which Road" level criteria in varied environments. Furthermore, outcomes from the GNSS denied environment align with predictions based on propagation error theory, demonstrating the feasibility of our navigation algorithm for tactical integrated navigation systems.

In recent years, most people use commercial integrated navigation systems to develop navigation algorithms. However, due to the different levels of sensors on the market, it is difficult to customize commercial systems and leads to limited development of navigation algorithms. Therefore, the purpose of this research is to develop a real-time integrated navigation system EGI-1000 (Embedded GNSS and INS) including software and hardware, and effectively reduce the cost with the commercial price. The real-time integrated navigation system EGI-1000 contains a navigation-grade IMU, IMU1000 and NovAtel OEM 7720 GNSS receiver module. In this research, the integration process can be divided into three parts. The first part is the integration of hardware, and the architecture diagram of the real-time integrated navigation system will be displayed. The second part is the pre-processing of data. In the multi-sensor time synchronization problem, this research will propose a method about cross-correlation to validate whether the timestamp of IMU data is delay. The last part is algorithm about fusing data from multiple sensors and motion constraints. Extended Kaman Filter (EKF) will be the core and motion constraints including Zero Velocity Update (ZUPT) and Non-Holonomic Constraints (NHC) are integrated in the Loosely Coupled (LC) scheme. The calibration of Inertial navigation Measurement Unit (IMU) will also be conducted to determine the parameter in algorithm. The results of the experiments will be shown in this paper. Both of hardware and navigation algorithm in the integrated navigation system of this research are used to conduct multiple experiment including open sky environments, GNSS challenging environments, and GNSS denied environment. In comparison with the reference data, the navigation accuracy of the developed integrated navigation system can achieve centimeter-level accuracy (“Active Control” level and “Where in lane” level) in open sky and GNSS challenging environments. According to the propagation error theory, the result in GNSS denied environment also meet the expected value. The navigation algorithm is also feasible for the commercial integrated navigation system.

The Lycocerus varipubens species-group is defined to accommodate three previously described species and a new species from the Himalayan area, including L. varipubens, L. semiextensus, L. purpurascens comb. nov. & stat. reinst. and L. zayuensis sp. nov. L. purpurascens, originally described in Cantharis and first combined in Lycocerus here, is reinstated as a valid specific name to replace L. rubrispinis syn. nov., which is a replacement name for Cantharis rubripennis. Meanwhile, L. rubrispinis becomes a junior synonym of L. purpurascens. L. varipubens species-group could be distinguished from all other groups by the combination of following characters, the filiform antennae, pronotum wider than long, reddish-brown elytra with weakly or moderately developed longitudinal costae, all pro- and meso-outer claws each with a digtiform tooth in both sexes, and spermatheca with three spiral tubes. The species descriptions are provided with habitus photos, aedeagi, abdominal sternites VIII and reproductive systems of female. L. purpurascens and L. varipubens are recorded to China for the first time. In addition, a morphological phylogenetic analysis shows that the L. varipubens group is sister to L. purpureus group. A distribution map and a key to the species of this species-group are also provided.http://www.zoobank.org/urn:lsid:zoobank.org:pub:7C82B6E4-9A71-4893-AD97-5692839D2236

Although flares from late-type main-sequence stars have been frequently detected in the multiwavelength, the associated dynamical process has been rarely reported so far. Here, we report follow-up observations of an X-ray transient triggered by Wide-field X-ray Telescope onboard the Einstein Probe at UT08:45:08 in 2024, May 7. The photometry in multibands and time-resolved spectroscopy started at 3 hr and 7.5 hr after the trigger, which enables us to identify the transient as a flare of the M-dwarf 2MASS J12184187−0609123. The bolometric energy released in the flare is estimated to be ∼10 ^36 erg from its X-ray light curve. The H α emission-line profile obtained at about 7 hr after the trigger shows an evident blue asymmetry with a maximum velocity of 200–250 km s ^−1 . The blue wing can be likely explained by the chromospheric temperature (cool) upflow associated with chromospheric evaporation, in which the mass of the evaporating plasma is estimated to be 1.2 × 10 ^18 g. In addition, a prominence eruption with an estimated mass of 7 × 10 ^15 g < M _p < 7 × 10 ^18 g cannot be entirely excluded.

The navigation means the process of determining the position, velocity, and orientation of the moving object such as the land vehicle, aerial vehicle, and even autonomous vehicle. Nowadays, Global Navigation Satellite System (GNSS) is most used for positioning. Nevertheless, the navigation system based on GNSS would be interrupted in the challenging environments. Therefore, the inertial navigation system (INS) has been widely combined with GNSS to overcome this issue. For INS, the core concept is the measurements of Inertial Measurement Unit (IMU). In order to integrate the measurements of IMU with several sensors such as GNSS receivers, odometers, and so on, we should transform the measurements of IMU from body frame to navigation frame. The initial alignment just represents the process of finding the accurate initial rotation matrix between body frame and navigation frame in the beginning of navigation. However, initial misalignment angles would cause large error of INS. Hence, obtaining an accurate initial rotation matrix from body frame to navigation frame is an important issue to get the better navigation performance. In the research, an integrated navigation system is developed to validate the initial alignment algorithm. With the data pre-processing and accurate calibration. the proposed method of initial alignment can get precise initial ration matrix. The errors of roll pitch, and yaw angle are all smaller than 1 degree after initial alignment. Moreover, the time threshold of initial alignment is set by manual traditionally. A method of finding threshold of coarse alignment is proposed in this research.

Purpose: To determine mortality and outcomes of patients diagnosed with fracture-related infections (FRIs). Methods: FRI patients treated at a trauma centre between 2001 and 2020 were analysed. The primary outcome was 1-year mortality; mortality associations with FRI organism, depth of involvement, and temporality were investigated with multivariable survival analysis. Healthcare-associated and serological outcomes were reported as secondary outcomes. Results: 311 FRIs with mean age of 67.0 and median Charlson comorbidity index of 0 were analysed. Methicillin-sensitive Staphylococcus aureus (MSSA) (29.9%) was the most frequently implicated organism. The majority of FRIs were deep infections (62.7%). FRIs were diagnosed at a median of 40 (IQR 15–200) days post index surgery. The mean follow-up was 5.9 years. One-year mortality amounted to 17.7%. MSSA FRIs were associated with better survival (adj HR 0.34, 95%CI 0.15–0.76, p = 0.008). There was no difference in survivorship between deep or superficial FRI (adj HR 0.86, 95%CI 0.62–1.19, p = 0.353) or in relation to onset time (adj HR 1.0, 95%CI 0.99–1.00, p = 0.943). Implant removal or debridement alone was performed in 61.7% and 17% respectively. Antibiotics was prescribed for 53 (IQR 23–110) days, and patients were hospitalised for 39 (IQR 19–78) days. CRP and ESR normalised in 70.3% (median 46 days) and 53.8% (median 86 days) patients respectively. Conclusion: Fracture-related infections are associated with significant mortality and morbidity regardless of depth and temporality. Non-MSSA FRIs are associated with inferior survival.

Abstract Background Prurigo nodularis (PN) is a highly pruritic, chronic dermatosis and difficult to treat. PN lesions are characterized by existence of many hyperkeratotic, erosive papules and nodules. However, the pathogenesis of PN still remains unelucidated. Aim To clarify the keratin role in the epidermis hyperproliferation, the keratin expression pattern in the PN lesional skin. Methods In this study, we enrolled 24 patients with PN and 9 healthy control volunteers. K1/K10, K5/K14, K6/K16/K17 expression pattern were investigated by using immunohistochemical staining. Results The lesional skin consists of the thickened spinous layers, in which active cell division was found. K5/K14 were upregulated in PN lesional epidermis, the staining signal localized in the basal layer and lower suprabasal layers. Hyperproliferation‐associated K6 was found in all layers of epidermal lesional skin, especially in the spinous layers. In contrast, K16 was only detected in the basal and lower suprabasal layers, K17 was observed in the basal and spinous layers. Terminal differential keratins K1/K10 were upregulated, detected in the pan‐epidermis, but spared in the basal and low suprabasal layers. Conclusion The keratinocytes enter an alternative differentiation pathway, which are responsible for the activated keratinocyte phenotype, abnormal keratins expression potentially contributes to the keratinocytes proliferation, subsequently lead to increased lesional skin epidermis thickness, hyperkeratiosis and alteration of skin barrier properties.

Street trees are common features and important assets in urban scenes. They are huge in numbers and are constantly changing, thus are difficult to monitor on a regular basis. A method of automatic extraction and dynamic analysis of street trees based on mobile LiDAR data is proposed. First, ground and low objects are filtered from the point clouds. Then, based on a geometric tree model and semantic information, each tree point cloud is extracted, and geometrical parameters such as location, trunk diameter, trunk structure line, tree height, crown width, and crown volume of each tree is obtained. A dynamic analysis combined with the growing characteristics of trees is conducted to compare and analyse the street trees from different epochs, in order to understand whether the trees have grown or been pruned, replanted, or displaced. The proposed algorithm was tested on three epochs of mobile LiDAR data, obtained in 2010, 2016 and 2018, respectively. Experimental results showed that the proposed method was able to accurately detect trees and extract tree parameters for detailed dynamics analysis.

A series of Co2−xRuxMnSi (x = 0, 0.25, 0.5, 0.75, 1) Heusler compounds were successfully synthesized. The heat-treatment conditions were crucial to make the materials form a single phase with a Heusler structure. With increasing Ru content, the half-metallic gap, lattice parameters and magnetization are continuously adjustable in a wide range. The Co2−xRuxMnSi (x = 0, 0.25) compounds are rigorous half-metals and show a T3 dependence of resistance at low temperature. The Co2−xRuxMnSi (x = 0.5, 0.75, 1) Heusler compounds are the nearly half-metallic materials and show a semiconductive dependence of resistance at low temperature. The experimental magnetization is consistent with that in theory and follows the Slater–Pauling rule. The Curie temperature is higher than 750 K for all Co2−xRuxMnSi Heusler compounds.

Longitudinal rf manipulation schemes have been widely employed for achieving various beam experiments and applications in heavy ion or proton (hadron) synchrotrons. For high-intensity hadron beams, longitudinal space charge and cavity beam loading play a key role in beam intensity limitations since they may cause beam oscillations and longitudinal emittance growth. Efficient schemes to compress such intense bunched beams and minimize the emittance blow-up during those manipulations are of practical concern. In this article, the behavior of the particle distribution in the presence of space charge and beam loading during bunch merging is investigated via a generalized elliptical bunch model and particle-in-cell (PIC) simulations. Possible schemes to minimize these intensity effects are discussed. As an application, parameters for the longitudinal rf manipulation scenario in the upcoming second phase of the China Spallation Neutron Sources (CSNS-II) are proposed. It is shown that for (slow cycling) storage rings, with an optimized set of longitudinal parameters, the emittance growth due to intensity effects can be largely dampened and a high compression efficiency is achieved. For rapid cycling synchrotrons, fast bunch merging can be achieved via a desynchronization method. The agreement between the analytical elliptical model and the PIC simulation results indicates that the extended model can be employed for the study of the intensity effects during longitudinal rf manipulations in hadron synchrotrons.

A typical nitrogen expanded austenite layer is formed by plasma-based low-energy nitrogen ion implantation (PBLEII) on AISI 304L austenitic stainless steel at a moderate temperature of 380 °C. The dislocation self-organization structure in the nitrogen expanded austenite layer is characterized as an evolution from partial and Lomer-Cottrell dislocations in the inner layer near the interface to multilayer stacking faults in the outer nitrided layer. The self-organized dislocation density and forms are essentially dependent on the plastic deformation, strain-gradient, and nitrogen-related stacking fault energies, respectively, due to the constrained expansion in the nitrided layer. As the nitrogen concentration in the austenitic matrix increases, the stacking fault energy gradually decreases, resulting in the transformation of the defect from Lamer-Cottrell dislocations to multilayer stacking faults. The appropriate stress, which is associated with orderly stress relief during dislocation self-organization, preserves the integrity of the nitrided layer with a combinedly improved in wear and corrosion resistance. Nitriding-induced dislocation self-organization is basically explored as the formation mechanism of the nitrogen expanded austenite layer, contributing to the development of the specific low-temperature nitriding austenitic steel.

A two-step treatment, first chemical etching then thermal treatment, is proposed to achieve an atomically flat and thermally stable TiO2-terminated SrTiO3 substrate. LaAlO3 films were then grown on those TiO2-terminated and as-received substrates. LaAlO3 films on the TiO2-terminated SrTiO3 substrate maintained the layer-by-layer growth mode with a sharp interface, while films on the as-received substrates easily underwent reconstruction adverse to the sharp interface. Both LaAlO3/SrTiO3 interfaces displayed metallic conductive behavior, while the difference in magnetotransport properties indicated the difference in origin for interface conductivity. Large positive magnetoresistance implied that the LaAlO3/as-received substrate interface was a 3D conductive interface dominated by oxygen vacancies. However, the annealed-LaAlO3/treated-substrate interface preserved intrinsic quasi-2D interface magnetism as evidenced by large negative magnetoresistance.

CsCl-type materials have many outstanding characteristics, i.e. simple in structure, ease of synthesis and good stability at room temperature, thus are an excellent choice for designing functional materials. Using high-throughput first-principles calculations, a large number of topological semimetals/metals (TMs) were designed from CsCl-type materials found in crystallographic databases and their crystal and electronic structures have been studied. The CsCl-type TMs in this work show rich topological character, ranging from triple nodal points, type-I nodal lines and critical-type nodal lines, to hybrid nodal lines. The TMs identified show clean topological band structures near the Fermi level, which are suitable for experimental investigations and future applications. This work provides a rich data set of TMs with a CsCl-type structure.

Engineering practice shows that the deformation of the slide-resistant pile may be transferred to the adjacent bridge foundation on an inclined slope, which can compromise the safety of the entire bridge. However, this phenomenon has rarely been considered in the past. To reveal the deformation transfer mechanism between the slide-resistant pile and the adjacent structures, a full-scale field test was performed on a high and steep slope located in a section of a certain railway. A numerical analysis model was constructed to simulate the field test and validate its parameters. Moreover, parametric analysis was also conducted to examine the influence of the pile length, pile diameter, and arrangement of the pile foundation. The results show that the bridge pile foundation is simultaneously affected by the “load transfer effect” caused by the slide-resistant pile and “traction effect” of the sliding slope. With the distance between the pile foundation and the slide-resistant pile increasing, the dominant factor affecting the deformation mode of the pile body is switched from the “load transfer effect” to the “traction effect.” Furthermore, a critical embedment depth exists for the bridge pile foundation built on a high and steep slope, which varies at different locations along the inclined stratum. In addition, using a pile arrangement with a larger pile diameter and lower number of piles is more beneficial for controlling the horizontal displacement of the bridge foundation. The results of the research provide a reference for the safety control of the engineering on the high and steep slope.

The anther culture technique, although it has been widely used in wheat breeding programs, is associated with a high albinism rate that limits its application. The mechanism of albinism has not been studied explicitly at the molecular level. In this study, differently expressed genes (DEGs) and proteins (DEPs) of albino and green seedlings from a wheat anther culture were analyzed and compared using transcriptomic sequencing (RNA-Seq), two-dimensional electrophoresis, and mass spectrometry. A total of 1 892 DEGs (1 115 down-regulated and 777 up-regulated) and 43 DEPs (15 down-regulated and 28 up-regulated) that are primarily involved in photosynthetic pathways and porphyrin and chlorophyll metabolism was identified when the albino group library was used as the control. Most DEGs participated in constructing components of thylakoids and the chloroplast envelope as determined via gene ontology analysis. The expression patterns of 12 selected genes were evaluated using real-time quantitative PCR, and the results were in agreement with the RNA-Seq analysis. Our results may assist the development of new methods to decrease the albino seedling rates in wheat anther cultures.

We proved that the critical thickness for metal-to-insulator transition (MIT) of LaNiO3 could be controlled by substrate orientation. By means of density functional theory calculations, films grown on SrTiO3 substrates with (001), (110) and (111) orientations have different amount of charge transfer across the interface. Different charge transfer induces different interfacial conductivity behavior and at the same time modifies the carrier density of adjacent LaNiO3 films. The manipulation of MIT by substrate orientation can be achieved through interfacial charge transfer induced interfacial conductive layer with the modified conductivity of LNO layer.

The objective of this study was to investigate the effects of reducing dietary phosphorus (P) on the frame size, udder traits, blood parameters and nutrient digestibility coefficient in 8- to 10-month-old Holstein heifers. Forty-five heifers were divided into 15 blocks according to the mo of age and were randomly assigned one of three dietary treatments: 0.26% (low P [LP]), 0.36% (medium P [MP]), or 0.42% (high P [HP]) (dry matter basis). Samples were collected at the wk 1, 4, 8. The results show that low dietary P had no effect on body measurement. The blood P concentration decreased with decreasing dietary P (p

In order to study the temporal and spatial variations of PM2.5 and its chemical compositions in the region of Beijing, Tianjin, and Hebei (BTH), PM2.5 samples were collected at four urban sites in Beijing (BJ), Tianjin (TJ), Shijiazhuang (SJZ), and Chengde (CD), and also one site at Shangdianzi (SDZ) regional background station over four seasons from 2009 to 2010. The samples were weighted for mass concentrations and analyzed in the laboratory for chemical profiles of 19 elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Ni, P, Pb, Sr, Ti, V, and Zn), eight water-soluble inorganic ions (Na+, NH4+, K+, Mg2+, Ca2+, Cl−, NO3−, and SO42−, and carbon fractions (OC and EC). The concentrations of PM2.5 and its major chemical species were season dependent and showed spatially similar characteristics in the plain area of BTH. The average annual concentrations of PM2.5 were 71.8–191.2 μg m−3 at the five sites, with more than 90% of sampling days exceeding 50 μg m−3 at BJ, TJ, and SJZ. PM2.5 pollution was most serious at SJZ, and the annual concentrations of PM2.5, secondary inorganic ions, OC, EC, and most crustal elements were all highest. Due to stronger photochemical oxidation, the sum of concentrations of secondary inorganic ions (NH4+, NO3−, and SO42− was highest in the summer at SDZ, BJ, TJ, and CD. Analysis of electric charges of water-soluble inorganic ions indicated the existence of nitric acid or hydrochloric acid in PM2.5. For all five sites, the concentrations of OC, EC and also secondary organic carbon (SOC) in the spring and summer were lower than those in the autumn and winter. SOC had more percentages of increase than primary organic carbon (POC) during the winter. The sums of crustal elements (Al, Ca, Fe, Mg, Ti, Ba, and Sr) were higher in the spring and autumn owing to more days with blowing or floating dust. The concentrations of heavy metals were at higher levels in the BTH area by comparison with other studies. In Shijiazhuang and Chengde, the PM2.5 pollution was dominated by coal combustion. Motor vehicle exhausts and coal combustion emissions both played important roles in Tianjin PM2.5 pollution. However, motor vehicle exhausts had played a more important role in Beijing owing to the reduction of coal consumption and sharp increase of cars in recent years. At SDZ, regional transportation of air pollutants from southern urban areas was significant.

It is thought that East Asian monsoon (EAM) is linked and sensitive to solar activity. In this paper, we have decomposed the Dongge cave speleothem δ18O record (proxy for EAM), and Δ14C and 10Be (proxies for solar activity) time series into variations at different time scales with the empirical mode decomposition (EMD) method to reveal the possible link between the EAM variability and solar activity. There are some common cycles in the EAM and solar variability from centennial to millennial scales, indicating a possible link between EAM and solar activity at these time scales. The correlation between EAM and solar activity is much higher at millennial scales than at centennial scales, which means direct responses to the solar variation are more likely at time scales longer than a few hundred years. At ~30, 60 and 600 yr time scales, the variation in EAM is amplified by the solar amplitude modulation at ~100, 200 and 2200 yr time scales.

We present systematic studies of the transient dynamics of GaAs by ultrafast time-resolved reflectivity. In photoexcited non-equilibrium states, we found a sign reverse in reflectivity change Δ R / R , from positive around room temperature to negative at cryogenic temperatures. The former corresponds to a free carrier metallic state, while the latter is attributed to an exciton insulating state, in which the transient electronic properties is mostly dominated by excitons, resulting in a transient metal–insulator transition (MIT). Two transition temperatures ( T _1 and T _2 ) are well identified by analyzing the intensity change of the transient reflectivity. We found that photoexcited MIT starts emerging at T _1 as high as ∼ 230 K, in terms of a dip feature at 0.4 ps, and becomes stabilized below T _2 that is up to ∼ 180 K, associated with a negative constant after 40 ps. Our results address a phase diagram that provides a framework for the inducing of MIT through temperature and photoexcitation, and may shed light on the understanding of light-semiconductor interaction and exciton physics.

The growth temperature of spacer layers (SPLs) is investigated as a means to obtain identical layers for multilayer quantum dot (QD) structures. A 5-layer 1.3-μm InAs/GaAs QD structure with 50-nm GaAs SPLs served as a model system. It is found that the growth temperature of the GaAs SPLs has pronounced effects on both the structural and optical properties of the InAs QDs. For GaAs SPLs grown at a low temperature of 510 °C, dislocations are observed in the second and subsequent layers, a result of significant surface roughness in the underlying spacer layer. However by increasing the growth temperature to 580 °C for the final 35 nm of the 50-nm GaAs SPLs, a much smoother surface is achieved, allowing the fabrication of essentially identical, defect free QD layers. The suppression of defect formation enhances both the room-temperature photoluminescence efficiency and the performance of 1.3-μm multilayer InAs/GaAs QD lasers. An extremely low continue-wave room-temperature threshold current density of 39 A/cm2 is achieved for an as-cleaved 5-layer device with emission at 1.306 μm and ground state operation up to 100 °C. [ABSTRACT FROM AUTHOR]

The formation and development of geospatial cognitive abilities are an important aspect of training geographic literacy of secondary students, because these abilities have vital significance for solving their own problems related to geography and its study. However, training geospatial cognitive abilities is currently quite weak in our secondary school's geography curriculum. Many secondary students now have low geospatial cognitive abilities. Remote sensing has a lot of advantages over other training in geospatial cognitive abilities. Therefore, how to use remote sensing in training geospatial cognitive abilities of secondary students should be given necessary importance. Based on the partition of essential factors of geospatial cognitive abilities, this study analyzed some advantages and summarized five teaching strategies integrating remote sensing in training geospatial cognitive abilities in our secondary education, which can provide applicable opinions and suggestions for developing geospatial cognitive abilities of secondary students. [ABSTRACT FROM AUTHOR]

This paper demonstrates an additive non-uniform random sampling and interrogation method for dynamic and/or static strain gauge using a reflection spectrum from two superimposed fiber Bragg gratings (FBGs). The superimposed FBGs are designed to generate non-equidistant space of a sensing pulse train in the time domain during dynamic strain gauge. By combining centroid finding with smooth filtering methods, both the interrogation speed and accuracy are improved. A 1.9 kHz dynamic strain is measured by generating an additive non-uniform randomly distributed 2 kHz optical sensing pulse train from a mean 500 Hz triangular periodically changing scanning frequency. [ABSTRACT FROM AUTHOR]

Graphene produced by chemical vapor deposition (CVD) methods has been considered as a promising corrosion prevention layer because of its exceptional structure and impermeability. However, the anti-corrosion performance and the failure mechanism are still controversial. In this study, graphene layers with different quality levels, crystallite sizes, and layer numbers were prepared on the surface of Cu by a CVD process. The effects of grain boundaries (GBs) on the failure of graphene layers to provide adequate protection were investigated in detail by combining graphene transfer techniques, computation, and anti-corrosion measurements. Our results reveal that corrosion rates decrease marginally upon the increase of graphene layer number, and this rather weak dependence on thickness likely arises from the aligned nature of the GBs in CVD-grown few-layer graphene. This problem can potentially be overcome by layer-by-layer graphene transfer technique, in which corrosion is found to be arrested locally when transferred graphene is present on top of the as-grown graphene. However, this advantage is not reflected in corrosion studies performed on large-scale samples, where cracks or imperfect interfaces could offset the advantages of GB misalignment. With improvements in technology, the layer-by-layer assembly technique could be used to develop an effective anti-corrosion barrier. [ABSTRACT FROM AUTHOR]

Cross section transmission electron microscopy has been used to analyse dislocation filter layers (DFLs) in five similar structures of GaAs on Si that had different amounts of strain in the DFLs or different annealing regimes. By counting threading dislocation (TD) numbers through the structure we are able to measure relative changes, even though the absolute density is not known. The DFLs remove more than 90% of TDs in all samples. We find that the TD density in material without DFLs decays as the inverse of the square root of the layer thickness, and that DFLs at the top of the structure are considerably more efficient than those at the bottom. This indicates that the interaction radius, the distance that TDs must approach to meet and annihilate, is dependent upon the TD density. [ABSTRACT FROM AUTHOR]

The effect of the internal stress on the two-way shape memory in Co49Ni21.6Ga29.4 single crystals has been investigated. We found that the internal stress generated natively by the solidifying process works as a tensile force along the growth direction. Applying different compressive pre-stresses along the [0 0 1] direction, the shape-memory strain can be continuously changed from +1.0% to [?]2.3%. In the [1 1 0] direction, the strain monotonically increases from [?]2.0% to [?]4.0% due to a strong detwinning produced by the consistent effect of the external and internal stresses. [ABSTRACT FROM AUTHOR]

Beet necrotic yellow vein virus (BNYVV) causes one of the most economically destructive diseases of sugar beet (Beta vulgaris), rhizoma-nia, which may reduce sugar yield by 80%. This field investigation was conducted to evaluate the interactions between spinach genotypes and different BNYVV strains, and to determine whether BNYVV is transmitted through spinach seeds. Eight commercial spinach cultivars were planted in two BNYVV-infested fields and two control fields in Salinas, CA in 2009. Spinach plants in the BNYVV-infested fields showed disease symptoms of yellow-green or light-green vein clearing, mottling, or yellow-green chlorotic lesions on younger leaves as early as 28 days after planting (four- to six-true leaf stage). Leaves may also become stiff, more crinkled, and necrotic. There was an increase of lateral roots and leaf number but a decrease in leaf weight compared to healthy plants. Infected plants often became stunted, deformed, wilted, and dead. Symptomatic leaves and roots from plants with or without leaf symptoms in BNYVV-infested fields all tested positive for BNYVV by enzyme-linked immunosorbent assay. A more aggressive (resistance-breaking) strain of BNYVV led to higher disease incidence in spinach than in the wild type. BNYVV was not transmitted through spinach seeds. There were significant differences in disease development among cultivars, with disease incidence ranging from 8 to 44%, suggesting that genetic improvement of BNYVV resistance through spinach breeding should be feasible. [ABSTRACT FROM AUTHOR]