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Growing evidence suggests that parasite-infected prey is more vulnerable to predation. However, the mechanism underlying this phenomenon is obscure. In small mammals, analgesia induced by environmental stressors is a fundamental component of the defensive repertoire, promoting defensive responses. Thus, the reduced analgesia may impair the defensive ability of prey and increase their predation risk. This study aimed to determine whether coccidia infection increases the vulnerability to predation in root voles, Microtus oeconomus (Pallas, 1776), by decreased analgesia. Herein, a predator stimulus and parasitic infection were simulated in the laboratory via a two-level factorial experiment, then, the vole nociceptive responses to an aversive thermal stimulus were evaluated. Further, a field experiment was performed to determine the overwinter survival of voles with different nociceptive responses via repeated live trapping. The coccidia-infected voles demonstrated reduced predator-induced analgesia following exposure to predator odor. Meanwhile, pain-sensitive voles had lower overwinter survival than pain-inhibited voles in enclosed populations throughout the duration of the experiment. Our findings suggest that coccidia infection attenuates predator-induced analgesia, resulting in an increased vulnerability to predation.

Three-dimensional (3D) heteroatom-doped nanostructured carbon materials have gained extensive attention because of their tremendous potential for enhancing supercapacitor performance. Herein, based on a mild carbonization/activation process we successfully developed green/sustainable 3D hierarchically porous nitrogen-doped nanostructure carbon (N–HNC) materials from houttuynia biomass, showing high specific capacitance and high cyclic stability. The as-prepared houttuynia-derived porous carbon material shows a unique flower-like architecture with well-distributed micro/meso pores and a high specific surface area of 2090 m2/g. The assembled supercapacitor based on N–HNC sample shows superior specific capacitance (473.5 F/g at 1 A/g) and remains over 50% of specific capacitance at 20 A/g. The N–HNC based symmetric supercapacitor, constructed with a two-electrode configuration, shows an energy density of 15.99 Wh/kg at 500 W/kg and outstanding capacitance retention of 95.74% even after 10,000 charge-discharge cycles at 10 A/g in an aqueous 6 M KOH electrolyte system. The results highlight the potential of the 3D porous N-doped hierarchical nano-structural carbon materials from houttuynia biomass as candidate electrodes for supercapacitor applications. This study provides an example of using the inherent framework structure of biomass as a precursor to synthesize hierarchically porous nitrogen-doped nanostructure for high-performance supercapacitor applications.

A numerical study on effects of hydrogen direct injection on hydrogen mixture distribution, combustion and emissions was presented for a gasoline/hydrogen SI engine. Under lean burn conditions, five different direct hydrogen injection timings were applied at low speeds and low loads on SI engines with direct hydrogen injection (HDI) and gasoline port injection. The results were showed as following: firstly, with the increase of hydrogen direct injection timing, the hydrogen concentration near the sparking plug first increases and then decreases, reaching the highest when hydrogen direct injection timing is 120°CA BTDC: Secondly, hydrogen can speed up the combustion rate. The main factor affecting the combustion rate and efficiency is the hydrogen concentration near the sparking plug: Thirdly, in comparing with gasoline, the NOX emissions with hydrogen addition increase by an average of 115%. For different hydrogen direct injection timings, the NOX emissions of 120°CA BTDC is the highest, which is 29.9% higher than the 75°CA BTDC. The hydrogen addition make the NOX emissions increase in two ways. On the one hand, the average temperature with hydrogen addition is higher. On the other hand, the temperature with hydrogen addition is not homogeneous, which makes the peak of temperature much higher. In a word, the main factor of NOX emissions is the size of high temperature zone in the cylinder: Finally, because the combustion is more complete, in comparing with gasoline, hydrogen addition can reduce the CO and HC emissions by 32.2% and 80.4% respectively. Since a more homogeneous hydrogen mixture distribution can influence a lager zone in the cylinder and reduce the wall quenching distance, these emissions decrease with the increase of hydrogen direct injection timing. The CO and HC emissions of 135°CA BTDC decrease by 41.5% and 71.4%, respectively, compared to 75°CA BTDC.

A comparative study on effects of homogeneous or stratified hydrogen on combustion and emissions was presented for a gasoline/hydrogen SI engine. Three kinds of injection modes (gasoline, gasoline plus homogeneous hydrogen and gasoline plus stratified hydrogen) and five excess air ratios were applied at low speed and low load on a dual fuel SI engine with hydrogen direct injection (HDI) and gasoline port injection. The results showed that, with the increase of excess air ratio, the brake thermal efficiency increases firstly then decreases and reaches the highest when the excess air ratio is 1.1. In comparison with pure gasoline, hydrogen addition can make the ignition stable and speed up combustion rate to improve the brake thermal efficiency especially under lean burn condition. Furthermore, it can reduce the CO and HC emissions because of more complete combustion, but produce more NOX emissions due to the higher combustion temperature. Since, in the gasoline plus stratified hydrogen mode, the hydrogen concentration near the sparking plug is denser than that of homogeneous hydrogen, the ignition is more stable and faster, which further speed up the combustion rate and improve the brake thermal efficiency. In the gasoline plus stratified hydrogen mode, the brake thermal efficiency increases by 0.55%, the flame development duration decreases by 1.0°CA, rapid combustion duration decreases by 1.3°CA and the coefficient of variation (COV) decreases by 9.8% on average than that of homogeneous hydrogen. However, in the gasoline plus stratified hydrogen mode, due to the denser hydrogen concentration near the sparking plug and leaner hydrogen concentration near the wall, the combustion temperature and the wall quenching distance increase, which make the NOX and HC emissions increase by 14.3% and 12.8% on average than that of homogeneous hydrogen.

Predators and parasites have been important extrinsic factors influencing the fluctuation of small mammal populations. They can have non-additive effects on a shared group of preys or hosts, which can have important consequences for population dynamics. However, experimental studies incorporating the interactions between predation and parasites are scarce in small mammal populations. Here we systematically examined the synergistic effects of predators and coccidian parasites interaction on overwinter survival and likely mechanisms underlying the synergistic effects in the root vole (Microtus oeconomus). Our aim was to test the general hypothesis that predators and coccidia interact synergistically to decrease overwinter survival of root voles through mediating vole's physiological traits and body conditions. We carried out a factorial experimental design, by which we manipulated the predator exclusion in combination with the parasitic removal in enclosures, and then measured fecal corticosterone metabolite (FCM) levels, immunocompetence, and body conditions in captured animals via repeated live trapping. We found a strong negative synergistic effect of predators and coccidia on survival. Importantly, we found that predators increased both the prevalence and intensity of coccidian infection in voles through immune suppression induced by predation stress, while increased coccidian infection reduced plasma protein and hematocrit level of voles, which may impair anti-predator ability of voles and lead to an increase in predation. Our finding showed when voles are exposed to both predation risk and infection, their synergistic effects greatly reduce overwinter survival and population density. This may be an important mechanism influencing population dynamics in small mammals.

Flexible supercapacitors with considerable energy storage performance from green/sustainable materials have attracted significant attention in many fields, such as portable and wearable electronics...

Gabbroic rocks in continental arcs constrain the composition of sub-arc mantle and the roles played by mafic magmas in the generation and differentiation of continental crust. Here, we report whole-rock elemental and isotope (Sr and Nd) compositions of ~50 Ma and ~30 Ma gabbroic rocks from the central and eastern Gangdese (CG and EG) batholith, southern Tibet. A key observation is the along-arc isotopic and geochemical variations of ~50 Ma gabbros and dykes: EG rock samples show enriched Sr Nd isotope compositions, with initial 87Sr/86Sr = 0.7053–0.7077 and eNd(t) = −4.3 to +1.1 (average −3.0), and have higher abundance of heavy rare-earth elements (HREEs), high field strength elements, and melt-mobile elements compared with CG samples, which yield initial 87Sr/86Sr = 0.7038–0.7043 and eNd(t) = +3.4 to +6.9. Geochemical evidence suggests that the Sr Nd isotope differences reflect those in the mantle sources and are not due to crustal interactions, indicating that the sub-Gangdese batholithic mantle exhibited different degrees of enrichment at least ~50 Myr ago. These observations, combined with previous data, suggest that the sub-Gangdese batholithic mantle exhibited along-arc segmentation at 92°E–93°E at 50 Ma. This segmentation occurred probably between 90 and 47 Ma and was a result of the different characteristics and variable additions of the enriching agents into the asthenospheric mantle. CG gabbroic rocks were derived from depleted asthenospheric mantle enriched by variable amounts of aqueous fluids from the Neo-Tethyan slab, whereas EG rocks were generated from asthenospheric mantle enriched by hydrous melts from Indian continental crust. This interpretation implies that Indian continental crust was subducted beneath the southern Lhasa subterrane prior to 47 Ma. Compared with ~50 Ma rocks, EG ~30 Ma dykes exhibit higher melt-mobile element abundance and stronger REE fractionations, and were generated from deeper, melt-enriched mantle, signifying that a lithospheric thickening event occurred between 50 and 30 Ma in the EG batholith.

Photon-counting detector array is very desired for high-resolution laser imaging based on direct time-of-flight measurement. Such systems have potential applications in remote sensing with long distances. We will perform three-dimensional imaging using a large InGaAs Geiger-mode avalanche photodiode array which has single-photon sensitivity. To improve the image quality with only a few photon detections, the photon counting imaging process is analyzed and a regularization method based on pixel spatial correlation is employed for image reconstruction. The performance of the method is compared with that of conventional maximum likelihood estimation on intensity and range image reconstructions of a building about six hundred meters away.

Environmental temperature has a significant impact on insect behavior. The present study aimed to determine the effects of temperature on the development, survival, and reproduction of Thrips hawaiiensis (Thysanoptera: Thripidae), an important flower-inhabiting thrips. These effects were evaluated at five constant temperatures (18, 21, 24, 27, and 30°C) on thrips reared in the laboratory on excised Gardenia jasminoides flowers. The developmental durations of egg, first instar, second instar, prepupa, pupa, and the entire immature stages were shortened in response to a temperature increase from 18 to 30°C. The highest generational survival rate was at 27°C (75.00%), whereas the lowest was at 18°C (46.00%). The minimum threshold and effective accumulated temperatures for completing a generation of T. hawaiiensis were 7.62°C and 171.26 degree-days, respectively. The highest fecundity (95.80) was at 27°C, but it was not significantly different than at 24°C (84.72) or 30°C (84.32). The highest oviposition rate of 5.57 eggs per female per day occurred at 27°C, which was significantly higher than at any other temperature. Both the highest intrinsic rate of increase, at 0.200, and net reproduction rate, at 44.97, for T. hawaiiensis were observed at 27°C, whereas the lowest values of 0.114 and 25.56, respectively, were observed at 18°C. These results suggest that T. hawaiiensis is well adapted to temperate conditions, with an optimal temperature range for development of 24 to 30°C, with the most suitable temperature for both development and reproduction being 27°C.

Early Jurassic plutonic rocks from the Central Lhasa block that range from gabbro to granite yield similar 206Pb/238U ages ranging from 187.6 Ma to 196.0 Ma. Gabbros and diorites are characterized by similar radiogenic 87Sr/86Sr(t) ratios that range from 0.7053 to 0.7060, unradiogenic eNd(t) values ranging from −4.2 to −2.5 and eHf(t) values ranging from −8.8 to −2.8. Compared with the intermediate to mafic rocks, the granites have much higher 87Sr/86Sr(t) ratios, from 0.7102 to 0.7127, and lower eNd(t) values, from −8.7 to −7.5, and eHf(t) values from −11.9 to −7.5. Elemental and isotopic data suggest that the gabbros were derived from a melt-modified subarc mantle, diorites represent derivatives produced by hornblende fractional crystallization of gabbros, and granites were generated by the melting of ancient crustal basement rocks. Combined with literature data, these results suggest that the Central Lhasa block, as well as parts of the Southern and Northern Lhasa blocks, also contains ancient crystalline basement rocks.

The Western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae), is one of the most destructive sucking pests of flowering plants. We examined behavioral responses of F. occidentalis adults to the floral volatiles of Rosa chinensis, Gardenia jasminoides, and Tagetes erecta in a Y-tube olfactometer with background visual cues (green, red, white, yellow, and blue backgrounds). The results show that F. occidentalis adults had similar responses under all the different background colors, but the responses by sex varied significantly when offered floral volatile or clean air. In pairings of floral volatiles, female F. occidentalis adults presented significant preferences (R. chinensis > G. jasminoides > T. erecta) in each treatment, while male F. occidentalis adults had no significant preference. Furthermore, the responses of female F. occidentalis adults to the three different floral volatiles compared with each other were greater under green and blue backgrounds than red, white, or yellow backgrounds. However, the responses of male F. occidentalis adults to floral volatiles were similar to all five backgrounds. These results indicate that female thrips could discriminate different floral volatiles, while male thrips could not. Both male and female thrips performed steady preferences of floral volatiles under all the five visual backgrounds, and the behavioral responses of female thrips to the floral volatiles could be enhanced under the green and blue backgrounds. These findings could hopefully aid in the development of effective trapping and monitoring strategies for this pest.

Recent studies in the Xiaru and Malashan gneiss dome of the Tethyan Himalaya, southern Tibet identify that Xiaru and Paiku tourmaline-bearing leucogranite dike formed at ~ 28–29 Ma. Together with ~ 28 Ma Kuday garnet-bearing leucogranites, it is demonstrated that the Himalayan orogenic belt experienced a major episode of crustal melting in the Mid-Oligocene. Geochemical data indicate that three suites of leucogranite are characterized by large variations in the major and trace element compositions as well as Sr–Nd isotope systematics, which could be explained by combined fractional crystallization and relative contributions of micas and accessory phases dissolved into a crustal melt during decompressional melting of metapelitic rocks. Documentation of Oligocene partial melting of crustal rocks could indicate that the exhumation of deep crustal rocks in the Himalayan orogenic belt could have started as early as Oligocene.

Social life cycle assessment is an important method to assess products’ social impacts throughout their life cycles. There are already some indicators and software to assist conducting social life cycle assessment. However, it is hard for users to share or reuse assessment results because of different application data structures. To resolve this problem, a knowledge-based social life cycle assessment–aided design method is developed in this research. With this method, all elements in the social life cycle assessment process are analyzed and represented as classes, their relationships are described as object properties, and the data structure is represented as data properties to construct an ontology system for social life cycle assessment. Based on the ontology, a social life cycle assessment–aided product development web is developed. According to the data property structure, a bidirectional mapping between database and ontology is realized using JENA and ontology-based data access, which enables the result data to be automatically inputted into ontology individuals. Thus, the result data can be accumulated, shared, and reused among users. A case study with a floor product as well as a user test is carried out to prove the feasibility and usability of the web. The ontology-based social life cycle assessment–aided design method provides users with a new high-efficiency approach, setting the foundation for the intellectualization of life cycle assessment.

Impregnated decorative paper was an important wood-based panel finishing material. However, traditional impregnated decorative paper was impregnated with melamine-formaldehyde resin, which will release formaldehyde and harm the human health. To solve this problem, small molecule polyacrylate-polyethylene glycol (PEG) adhesive was used to achieve the non-formaldehyde addition of the impregnation system. The dialdehyde modified CNF (D-CNF), modified by sodium periodate (NaIO4), and triethylenediamine were introduced to enhance the surface properties of the impregnated decorative paper. The results showed that the incorporation of D-CNF and triethylenediamine imparted excellent physical strength and surface properties to impregnated decorative paper. When the dosage of 0.3 wt% D-CNF and 3 mL/100 g triethylenediamine in the compound emulsion, the hardness, abrasion resistant value and surface bonding strength of impregnated decorative paper adhered fiberboard reached 3H, 330 r of damage and 1.13 MPa, respectively. Thus, it could be effectively used for making high-performance formaldehyde-free impregnated decorative paper.

We report on the fabrication of Nd:YCa4O(BO3)3 (Nd:YCOB) ridge waveguides by combining carbon ion irradiation and precise diamond blade dicing. The guiding and spectroscopic properties of the planar as well as ridge waveguides are investigated. The second harmonic generation (SHG) at 532 nm has been realized through the waveguide structures. With nearly the same input power, the maximum average output powers are 0.56 mW and 0.62 mW, and the maximum conversion efficiencies reach 0.3%W−1 and 0.5%W−1, for planar and ridge waveguides, respectively.

A novel two-stage reheating process with new alloy design has been developed to improve the microstructure morphology of semisolid Al-Si casting aluminum alloy for thixoforming. The process consists of first reheating the material to the liquidus temperature, holding for 5 min, and then lowering to the predetermined two-stage reheating temperature between 843–863 K and holding for 10 min. The experimentally-obtained grain diameter, roundness, and the amount of liquid trapped within the solid phase were characterized, along with the microstructure obtained using the traditional feedstock reheating process. The Wilcox test (with α = 0.05) was then applied to statistically analyze the measured differences in the microstructures obtained using the two different processing routes. It was found that a refined near-spherical structure with uniform globule size, higher sphericity, lower coarsening rate constant, and less entrapped liquid was obtained via the new two-stage reheating process in comparison with the microstructure obtained using the traditional feedstock reheating process.

We report the surface cladding-like waveguide fabricated by the cooperation of the ultrafast laser writing and the ion irradiation. The ultrafast laser writes tracks near the surface of the Nd:YAG crystal, constructing a semi-circle columnar structure with a decreased refractive index of – 0.00208. Then, the Nd:YAG crystal is irradiated by the Carbon ion beam, forming an enhanced-well in the semi-circle columnar with an increased refractive index of + 0.0024. Tracks and the enhanced-well consisted a surface cladding-like waveguide. Utilizing this cladding-like waveguide as the gain medium for the waveguide lasing, optimized characterizations were observed compared with the monolayer waveguide. This work demonstrates the refractive index of the Nd:YAG crystal can be well tailored by the cooperation of the ultrafast laser writing and the ion irradiation, which provides an convenient way to fabricate the complex and multilayered photonics devices.

We report on the superficial cladding waveguides fabricated by direct femtosecond laser writing in Nd: CaF2 crystal with three different groups of parameters. The lowest propagation loss of waveguides has been determined to be 0.7 dB/cm at wavelength of 632.8 nm along TE polarization. The near fundamental modal distributions have been imaged through the end-face coupling technique. The guidance of the waveguides is found to possess low sensitivity on polarization of the probe light. By using a confocal microscope system, the micro-photoluminescence mappings and micro-fluorescence spectra are also obtained, which indicates the photoluminescence features of the Nd3+ ions are well preserved in the waveguide cores after direct femtosecond laser writing., The work is supported by Specialized Research Fund for the Doctoral Program of Higher Education of China (20130131130001); the 111 Project (No. B13029); Fundamental Research Funds for Shandong University (No. 2014JC002). JRVA thanks support from Junta de Castilla y León (Project SA116U13).

The Raman lidar has been developed and installed in the Beijing from November to December in 2014 for the observation of the spatial and vertical characteristics of aerosol and water vapor in the planetary boundary layer. During the experiments, the Raman lidar operates in the automatic and continuous mode with the spatial resolution of 7.5 m and the temporal resolution of 15 min. The observation results show that the aerosol extinction always increases along with the greater content of water vapor and the lower height of planetary boundary layer. It implies that the decrease of air quality in Beijing is associated with the water vapor in the air and the height of planetary boundary layer beside the enrichment of local and transported aerosols.

Cellulose nano-crystals (CNC) have attracted great interests as a novel nanostructured material in recent years, thanks to their excellent mechanical properties, high surface area and lightweight and biocompatibility etc. Due to its low charged group content, CNC prepared from the hydrochloric acid hydrolysis has poor dispersibility in water, which hinders its further applications. In this work, well-dispersed cellulose nano-crystals are successfully prepared using a two-step method, consisting of hydrochloric acid hydrolysis, followed by adsorption of hexadecyl trimethyl ammonium bromide (CTAB) onto CNC. Results show that CTAB at a low concentration (0.13–0.47 mM) provides effective steric barriers to minimize the CNC aggregation, which is supported by TEM images and particle size distribution of CNC. At high CTAB concentrations (>0.5 mM), CNC aggregation occurs, which is due to the “bridging” effect of CTAB.

We report on the fabrication of ridge waveguides in KTiOPOsub4/subnonlinear optical crystals through carbon ion irradiation followed by precise diamond blade dicing. The diced side-walls have low roughness, which allows for low propagation loss of ~1dB/cm in fabricated of ridges. The waveguide property investigation has been performed at 1064 nm as well as 532 nm, showing good guidance at both TE and TM polarizations. Based on type II phase matching configuration, efficient second harmonic generation of green light at room temperature has been realized. High conversion efficiencies of ~1.12%Wsup-1/supand ~12.4% have been obtained for frequency doubling under the pump of continuous-wave (CW) and pulsed fundamental waves at 1064 nm, respectively.

The nonlinear optical property of topological insulator bismuth selenide (Bi2Se3) is found to be well-tailored through ion irradiation by intentionally introducing defects. The increase of the optical modulation depth sensitively depends on the careful selection of the irradiation condition. By implementing the ion irradiated Bi2Se3 film as an optical saturable absorber device for the Q-switched wave-guide laser, an enhanced laser performance has been obtained including narrower pulse duration and higher peak power. Our work provides a new approach of tailoring the nonlinear optical properties of materials through ion irradiation, a well-developed chip-technology, which could find wider applicability to other layered two-dimensional materials beyond topological insulators, such as graphene, MoS2, black phosphours etc.

We report on the thermally manipulable waveguide laser emission by integrating the ultra-thin vanadium dioxide membrance with the waveguide as the saturable absorber. Combined with the study of unique optical features of the vanadium dioxide, the waveguide laser exhibits the significant laser operation switching between the picosecond laser and the continuous-wave laser. The saturable absorption of the vanadium dioxide exhibited the thermal hysteresis. Hence the continuous and picosecond laser can exist at the same temperature and can be respectively excited by the cooling and heating treatment.

This work demonstrates the realization of a lasing in scattering media, which contains dispersive solution of ZnO nanoparticles (NPs) and laser dye 4-dicyanomethylene-2-methyle-6-(p-dimethylaminostyryl)-4H-pyran(DCM) in negative liquid crystals (LCs) that was injected into a cell. The lasing intensity of the dye-doped negative LC laser can be tuned from low to high if the NPs concentration is increased. The tunability of the laser is attributable to the clusters-sensitive feature in effective refractive index of the negative LCs. Such a tunable negative liquid crystal laser can be used in the fabrication of new optical sources, optical communication, and liquid crystal laser displays.

This work reports on the passively Q-switched waveguide laser system based on Nd:YAG crystal and MoS2 satuable absorber. A depressed cladding waveguide with circular cross-sectional geometry has been produced in Nd:YAG crystal by direct femtosecond laser writing at low-repetition rate. The confocal microscopic investigation of the structure reveals the well-preserved microphotoluminescence features in the waveguide core. With chemical-vapor-deposition (CVD) MoS2 membrane as satuable absorber, the passive Q-switching of the Nd:YAG waveguide system has been achieved under optical pump, reaching maximum average output power of 85.2 mW, corresponding to single-pulse energy of 112 nJ, at wavelength of 1064 nm. The repetition rate of the pulsed waveguide laser system is tunable from 0.51 to 1.10 MHz, and the obtained minimum pulse duration is 203 ns., The work is supported by the National Natural Science Foundation of China (No. 11274203) and Junta de Castilla y León under Project SA086A12-2. Support from the Centro de Láseres Pulsados (CLPU) is also acknowledged.