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In order to reduce the absorption of solar radiation by asphalt pavement in plateau permafrost regions and protect the underlying permafrost subgrade, the aim of this research was to develop a dark high near-infrared (NIR) reflective material using magnesium phosphate cement (MPC) and chrome black T, and to construct reflective grouting compound pavement (RGCP) by grouting the material into large void asphalt mixture. The optimal magnesium (M)/phosphate (P) ratio of MPC was determined to be 10 through solar spectral reflectance test, with a NIR reflectance of 71.74 %. A series of experiments, including chromaticity characteristics, reflectance test, SEM-EDS analysis, and strength test, were conducted to characterize the impact of chrome black T content on the reflection and mechanical properties of MPC. The results indicated that the chrome black T particles were uniformly distributed on the surface of MPC and filled in its pores, which not only effectively colored the MPC, but also improved its mechanical strength. Since the reflectivity of chrome black T was lower than that of MPC, its incorporation also reduced the NIR reflectivity of MPC to a certain extent. Overall, MPC with 1 % chrome black T content had a color similar to asphalt and a NIR reflectance of 43.91 %, making it a suitable dark NIR reflective material. An indoor irradiation experiment verified that RGCP can maintain a lower temperature under solar radiation. Compared with the control group, the surface temperature of the RGCP specimen was reduced by 4.5 °C. • Reflective grouting compound pavement (RGCP) was prepared by grouting dark MPC into large void asphalt mixture. • MgO particles are the main provider of reflectivity in MPC. • The addition of chrome black T can not only effectively color the MPC, but also improve its mechanical strength. • RGCP has high near-infrared reflectance and can maintain lower temperatures under solar radiation. [ABSTRACT FROM AUTHOR]

Solution processable organic light‐emitting diodes (OLEDs) based on thermally activated delayed fluorescence (TADF) emitters show inferior efficiency to devices produced via vacuum deposition. In this context, solution‐processed hybrid white OLEDs are fabricated using a TADF molecule and iridium complex as the blue and red dopants, respectively. First, solution‐processed OLEDs employing a tristriazolotriazine‐based TADF as the blue dopant are designed and fabricated, yielding maximum external quantum efficiency (EQEmax) of 23.23% with an emission peak at 492 nm. Use of the optimized tristriazolotriazine‐based TADF OLED structure and additional red phosphor achieves highly efficient white light emission with an EQEmax of 22.57%, stable Commission International de l'Eclairage (CIE) coordinates of (0.34, 0.34), a correlated color temperature of 5000 K, and a color rendering index of 73. Impressively, accelerated lifetime testing shows the white OLED possessing a lifetime to 80% of initial luminance (LT80) of 40 h, and an LT50 of 298 h. To the best of knowledge, the device performance demonstrated in this work is one of the best comprised of solution‐processed blue and fluorescent‐phosphorescent hybrid white OLEDs. This research provides a reliable method for high efficiency solution processable blue TADF and TADF‐phosphorescent hybrid OLEDs. [ABSTRACT FROM AUTHOR]

• A new transversal heat transfer channel structure was first proposed here. • The structure can quickly transfer heat accumulated in asphalt pavement to road shoulders. • Transverse thermal conductivity of asphalt mixtures is significantly improved. • The structure provides a new method for active cooling of asphalt pavement. On the Qinghai-Tibet Plateau, intense solar irradiation will cause serious heat accumulation in asphalt pavement. Downward heat transfer will disturb the permafrost under subgrade, thus leading to a series of subgrade and pavement diseases. This makes construction of asphalt pavement in the permafrost regions of the Qinghai-Tibet Plateau a world-class challenge. This paper proposes for the first time a transversal heat transfer channel in asphalt pavement, which can quickly transfer heat accumulated in pavement to road shoulders. Finite element software ABAQUS was used to simulate the rutting plate with high axial thermal conductivity carbon fibers inserted transversely. Under the constant heat load of 500 W / m 2 , the heat flux near the carbon fibers showed the characteristic of convergence. The maximum transverse heat flux in the carbon fibers reached 4.97 × 10 7 W / m 2 , which was 14 times that in the asphalt mixture. Meanwhile, the maximum vertical heat flux in the carbon fibers reduced to 2.62 × 10 6 W / m 2 , which was 12 % less than the asphalt mixture. The effective thermal conductivity of composite specimens with different carbon fiber parameters was studied through control experiments. When the axial thermal conductivity, volume fraction and number of carbon fiber bundles increased to 100 W / m · ° C , 10.72 % and 4 bundles respectively, the transverse ETC of composite specimens increased to 4.05 W / m · ° C , 7.09 W / m · ° C and 16.18 W / m · ° C respectively. They were 3.12 times, 5.45 times and 12.45 times of the control group. The radial thermal conductivity of carbon fibers has a significant effect on the vertical ETC. When it decreased to 0.2 W / m · ° C , the vertical ETC decreased by 6.15 % compared with the control group. The temperature variation trend of specimens were measured by a laboratory irradiation experiment. The maximum temperature difference between the control group and the experimental group at 0 mm was 5.81 °C, and the average temperature difference within 2 h was 5.14 °C. The maximum temperature difference at 50 mm was 3.84 °C and the average temperature difference within 2 h was 3.24 °C. The results showed that the transverse heat transfer channel can reduce downward heat transfer. The application of the channels will enhance transverse heat release and relieve heat accumulation of asphalt pavement. This can create a low temperature state for pavement structure and has a positive effect on maintaining the stability of the permafrost regions on the Qinghai-Tibet Plateau. [ABSTRACT FROM AUTHOR]

To reduce costs and prevent environmental pollution in the fabrication process of straws fibrosis, a simple and efficient method of straw-reinforced asphalt concrete is proposed, which adds short-thin wheat straw pieces (SWSPs) into asphalt mixture directly. The road performances of wheat straw asphalt mixture (WSAM) are evaluated by means of three-point flexural test, rutting test, freeze thaw split test and the test of fracture toughness. The results show that when the SWSPs content is between 0.1% and 0.2%, the flexural strength of asphalt mixture increases by 23%, the dynamic stability by 48% (reaching 1592 times), fracture toughness by 27% while the rut depth decreases by 44%. It is indicated that high temperature stability of the asphalt mixture and low temperature crack resistance are intensified by adding an appropriate amount of SWSPs, and the results of freeze thaw split test manifest that the moisture susceptibility of WSAM is weaker. [ABSTRACT FROM AUTHOR]

Solution-processed thermally activated delayed fluorescence (TADF) emitter is a promising strategy in organic light-emitting device (OLED). In this contribution, the novel emitters named IPy-Ac was synthesized and characterized, in which imidazolopyrazine (IPy) moiety is used as the acceptor and acridine (Ac) is employed as the donor group. In addition, the corresponding emitters (Py-Ac) using pyrazine (Py) as the acceptor are prepared to comparison. Both compounds exhibit clear TADF character in the host matrix. The molecular structure-property relationship is investigated via both calculated and experimental methods. Using both emitters as the dopant, solution-processed OLEDs are fabricated and the IPy-Ac based device achieves the best performance with a maximum external quantum efficiency of 6.36%. This research demonstrates that the IPy moiety can be a promising electron acceptor for the design of TADF materials. Two novel TADF emitters bearing imidazolopyrazine/pyrazine as the acceptor moiety were designed and synthesized. The molecular structure-property relationship was explored in detail. The solution-processed OLEDs based on these two emitters achieved a maximum EQE of 6.36% at 504 nm. [Display omitted] • Two novel imidazolopyrazine/pyrazine-based emitters are prepared. • Both emitters exhibit TADF character in host matrix. • The molecular structure-property relationship is investigated. • The solution-processed OLEDs achieve a maximum EQE of 6.36% at 504 nm. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency and durability of semiconductor photocatalyst for degrading vehicle exhausts, a highly active degradation micro-unit was designed by crosslinking nano-TiO 2 to the surface of fine crumb rubber with coupling agent. The dependence of degradation efficiency of NO 2 on preparation parameters and test conditions were studied. Laboratory tests showed that the degradation rate of NO 2 could reach 90% under the appropriate test environment such as initial NO 2 concentration of 20 mg/m 3 , a mercury lamp with illumination of 1000 lx, temperature of 25 °C, relative humidity of 50% and rubber powder of 80 mesh. Tunnel tests showed that the concentration of NO 2 in test section was 0.1–0.3 mg/m 3 lower than those of contrast sections and the degradation rate reached 60% in 1 h. Since a three-dimensional contact area among nano-TiO 2 , exhausts, moisture and light was formed on the surface of rubber powders, the proposed technology is expected to provide a new way for greatly improving the degradation efficiency of vehicle exhaust by asphalt pavements. [ABSTRACT FROM AUTHOR]

The absorption of solar radiant heat is the primary reason for the high temperature of asphalt pavement and the exacerbation of the urban heat island effect. In this paper, a novel unidirectional heat-transfer (UHT) asphalt pavement structure was proposed, which allows heat transfer along a fixed direction. The UHT effect was demonstrated under lamp lit indoor and sunlit outdoor environments. Compared with the control specimens, the UHT specimens were able to reduce the surface temperatures of 6.2°C (day) and 1.3°C (night), after one day's cycle of simulating indoor heat absorption and release. The outdoor measurements showed that reductions of 3.4 and 1.2°C in the surface temperature of the UHT specimens were achieved during the day and night, respectively, when compared with the temperature of the control specimens. The calculation results also indicated that more than of heat was introduced into the soil and less than of heat was transferred out of the UHT specimens, which validated the self-cooling effect of the designed UHT structures. The proposed gradient thermal conductivity structure is a promising new technology to mitigate the urban heat island effect. [ABSTRACT FROM AUTHOR]

Highlights: [•] ESO was used to improve the short-term aging resistance of crumb rubber asphalt. [•] The performance of CRIMIESO modified asphalt was investigated. [•] Mechanism of aging resistance of CRIMIESO modified asphalt was discussed. [Copyright &y& Elsevier]

• A new grouting compound directional heat induced structure was first proposed. • The structure can significantly adjust the heat budget of the pavement. • Internal heat transfer is induced and driven rapidly in a directional way. • It provides a new grouting compound method for actively cooling pavement. In order to control directional heat induced efficiency and reduce pavement temperature, a grouting compound directional heat induced structure (GC-DHIS) was proposed and analyzed in this paper. The structure was formed by pouring grout with different thermal conductivity successively into the same matrix asphalt mixture framework. According to the structural characteristics of grouting compound pavement and the principle of gradient thermal conductivity, the heat in the pavement could be quickly transferred down to the subgrade. The heat transfer performance and cooling effect of GC-DHIS were studied by finite element simulation, and the simulation results were verified by laboratory irradiation experiment. The results showed that the heat exchange between the designed structure and the atmosphere in the endothermic and exothermic periods was 7.10% and 7.98% less than that of the control structure, respectively. Moreover, the effective downward heat transfer rate of pavement throughout the day could be improved, and the maximum temperatures inside the pavement were reduced by 0.9 °C(2 cm), 1.9 °C(5 cm) and 0.8 °C(10 cm). The GC-DHIS with gradient high thermal conductivity grout increased the total downward heat transfer at the depth of 2 cm, 5 cm and 10 cm by 7.0%, 11.9% and 17.4% during the endothermic period. Meanwhile, the surface temperature of this structure in this period showed a slower rising trend. Therefore, it could be concluded that GC-DHIS is a promising pavement structure with the function of actively enhancing heat directional transfer and cooling pavement. [ABSTRACT FROM AUTHOR]

• Carbon fibers are used to build directional heat-induced channels. • Channels induced heat convergence and fast heat conduction in asphalt mixtures. • Directional thermal conductivity of asphalt mixtures is significantly improved. • Channels will help improve the efficiency of asphalt solar collectors. Low thermal conductivity makes heat conduction in asphalt pavements quite slow, restricting asphalt solar collectors. To enhance the directional thermal conductivity of asphalt mixtures and induce directional heat transfer, directional heat-induced channels are built in asphalt mixtures by using carbon fibers with high axial thermal conductivity. A finite element method is used to simulate and study the temperature field and heat flow distribution of asphalt mixtures. A parametric analysis of the carbon fiber parameters is performed to evaluate the variation in the performance of the effective thermal conductivity of asphalt mixtures. The temperature trend of asphalt mixtures is measured by an indoor irradiation experiment and compared with the simulation results. The results show that heat-induced channels have obvious heat convergence effects and can induce heat to be efficiently conducted along its axial direction. These channels can significantly improve the directional thermal conductivity of asphalt mixtures and are expected to play a heat transfer bridge between the pavement surface and the energy collection system when using them in asphalt solar collectors in the future. [ABSTRACT FROM AUTHOR]

Blue emitters with thermally activated delayed fluorescence (TADF) characteristics have attracted much attention from both academic and industrial researchers in organic light-emitting diodes (OLEDs). In this contribution, three blue molecules of TTT-Ph-Cz, TTT-Ph-Ac and TTT-Ph-BAc in which the tristriazolotriazine (TTT) was employed as the electron acceptor and arylamine (carbazole and acridine derivatives) as the electron donor were prepared and characterized. Both the acridine-substituted compounds (TTT-Ph-Ac and TTT-Ph-BAc) displayed the blue TADF emission between 460 and 470 nm in film state. Additionally, the TTT-Ph-BAc showed clear aggregation-induced emission character. The solution processed OLEDs based on these three molecules were fabricated, and the TTT-Ph-Ac based device displayed a maximum external quantum efficiency of ～10% and peak wavelength of 480 nm. This research demonstrates that this novel TTT core can be a promising electron accepting unit for the design of TADF materials. Three blue molecules of TTT-Ph-Cz, TTT-Ph-Ac and TTT-Ph-BAc based on tristriazolotriazine (TTT) core were reported in this contribution. Both the acridine-substituted compounds (TTT-Ph-Ac and TTT-Ph-BAc) displayed the blue TADF emission in the wavelength range between 460 and 470 nm in film state. A maximum external quantum efficiency of ～10% and peak wavelength of 480 nm was achieved by the solution processed OLEDs. Image 1 • Tristriazolotriazine (TTT) Core was used as a novel acceptor in TADF molecules. • Three blue molecules of TTT-Ph-Cz, TTT-Ph-Ac and TTT-Ph-BAc were prepared. • Intense blue emissions between 430 and 470 nm were achieved in film state. • TTT-Ph-Ac based device demonstrated a maximum EQE of ～10% and peak wavelength of 480 nm. [ABSTRACT FROM AUTHOR]

Phase change hydrogel (PCH) combines the heat storage characteristics of phase change material with the water retention capacity of hydrogel, showing great potential in cooling pavement applications. This study aims to investigate the water retention and heat storage properties of PCH in cooling pavement, providing new insights for mitigating the urban heat island effect. Based on the principle of osmotic pressure, polyethylene glycol (PEG) solution was actively absorbed by superabsorbent polymers (SAP) to form stable PCH. By infusing the asphalt mixture skeleton with PCH-containing phase change grouting material (PCGM), a temperature-regulating phase change grouting pavement (PCGP) can be obtained. Morphological characterization showed that PCH was uniformly distributed in PCGM and effectively locked PEG during high temperature and water absorption/release processes without leakage. PCH imparted excellent water retention properties to PCGM, with a saturation water absorption rate of 44.1 %, which is 6.2 times higher than the control group, and a water retention rate of 34.31 % after heating at 60 °C for 12 hours. Furthermore, PCGM exhibited considerable heat storage performance, with a melting enthalpy of 15.74 J/g and a crystallization enthalpy of 12.07 J/g. Based on these, PCGP demonstrated outstanding temperature-regulating ability, reducing surface temperatures by 9.3 °C and 11.6 °C under dry and saturated conditions, respectively, compared to control pavement. In conclusion, this study provides a theoretical basis for the development of novel cooling pavement materials and shows great potential for its wide application in urban infrastructure construction. • A novel phase change hydrogel is developed based on the principle of osmotic pressure. • PCH endows pavement with excellent heat storage and water retention capabilities. • Phase change grouting pavement exhibits exceptional temperature-regulating ability. [ABSTRACT FROM AUTHOR]

• A new gradient heat conduction channel (GHCC) structure was first proposed here. • The structure can gather heat from asphalt pavement into the small channels. • The structure can induce and drive accumulation heat in a directional migration way. • It provides a new principle of active cooling for asphalt pavement. In order to enhance the heat transfer efficiency in asphalt pavement along a directional way, a gradient heat conduction channel structure (GHCC) was suggested and analyzed in this paper. The designed structure could gather heat from asphalt pavement into the channel and quickly transfer it to its subgrade along the axis of these channels in the pavement. Thermal analyses of GHCC were performed by a finite element method. The results showed that the maximum heat release of pavement with GHCC could be increased by 11.5 times. And the pavement temperatures at the upper surface and 4 cm were reduced by 2.1 °C and 6.1 °C, respectively. And the maximum downward heat transfer efficiency of the structure could be increased by 17.6 times. A strong horizontal heat flow was observed which was caused by a significant heat exchange between the channels and the surrounding asphalt mixtures. In order to verify the laboratory cooling effect of the structure, a laboratory irradiation experiment was also employed to verify the principles and models of the GHCC. All of these analytical tests showed that establishing the GHCC in asphalt pavements is a promising method to enhance heat release efficiency, endowing asphalt pavement with more active cooling function. [ABSTRACT FROM AUTHOR]

Efficiently and actively dissipating accumulated heat within asphalt pavement is crucial for reducing pavement distress and improving subgrade stability. This paper proposed a novel inverted "T" shaped heat induced structure (IT-HIS) that facilitates the rapid transfer of heat from the pavement to the subgrade and shoulders. The IT-HIS consists of two components: a vertical gradient thermal conductivity structure utilizing steel slag, and a horizontal oriented carbon fiber heat induced structure. The heat transfer behavior of the IT-HIS was analyzed using a finite element heat transfer model created in ABAQUS, and the results were validated through indoor irradiation experiments. The findings demonstrated that the IT-HIS enhanced heat flow and promoted secondary aggregation in the vertical direction, while facilitated lateral heat dissipation. Compared to the ordinary group (OG), the heat flux of IT-HIS at depths of 5 cm and 6.5 cm increased by 19.8 % and 64.6 %, respectively. The indoor irradiation experiment results indicated that during the heat absorption period, the IT-HIS reduced temperatures at depths of 0 cm, 2 cm, and 5 cm by 1.5 ℃, 1.7 ℃, and 1.1 ℃, respectively. During the heat dissipation period, the IT-HIS reduced temperatures at depths of 0 cm, 5 cm, and 10 cm by 0.9 ℃, 0.7 ℃, and 1.8 ℃, respectively. The IT-HIS enhanced the cooling effect during daytime and inhibited heat upward during nighttime based on the gradient thermal conductivity structure. The proposal and validation of this structure provide a fundamental approach to forming large-scale high-speed microchannel heat dissipation within asphalt pavements, and is expected to provide experimental and theoretical foundations for the development of directional active cooling technologies. • In order to reduce heat accumulation within asphalt pavement, this paper proposed a novel inverted "T" shaped heat induced structure (IT-HIS). • IT-HIS enhanced heat flow and promoted secondary aggregation in the vertical direction, while facilitated lateral heat dissipation. • IT-HIS enhanced the cooling effect during daytime and inhibited heat upward during nighttime. [ABSTRACT FROM AUTHOR]

Polymorphism, the intrinsic character of one chemical compound with at least two distinct phase arrangements, plays a very key role in the photophysical properties. In this contribution, four ′T′‐shaped molecules bearing the 2,1,3‐benzothiadiazole (BTD) skeleton, named 5 a–5 d, were prepared and characterized. All compounds exhibited excellent thermal stability and polymorphism in the solid state, evident from thermogravimetric analysis, differential scanning calorimetry, and polarized optical microscopy results. Intense emissions with high photoluminescent quantum yields were achieved both in solution (56–97 %) and neat films (33–98 %). All compounds possessed clearly pH‐dependent luminescence properties in solution. Additionally, compound 5 d showed useful mechanochromic luminescence owing to the transformation between the crystal and amorphous state. Employing compounds 5 a–5 d as the dopant, solution‐processable organic light‐emitting diodes (OLEDs) were fabricated and presented a highest external quantum efficiency of 6.15 %, which is higher than the theoretical value of fluorescence‐based OLEDs (∼5 %). This research provided a novel strategy for designing high‐efficiency BTD‐based polymorphic luminescent materials. [ABSTRACT FROM AUTHOR]

Highlights • A novel solar reflective coating was proposed. • The proposed coating has functional gradient multilayer structure. • The proposed coating could alleviate the high temperature of asphalt pavement. • The proposed coating had high cooling efficiency, safety and durability. • The proposed coating provides a new direction for pavement coating. Abstract Solar reflective coating is an effective way to reduce the surface and internal temperature of asphalt pavements. Existing coating is limited by its single-layer structure, and its development has persistent challenges, highlighting a need to study novel coating with high cooling efficiency, safety and durability. In this paper, a solar reflective coating with functional gradient multilayer structure was designed, named FGMC. It consisted of three different functional layers arranged in a gradient from top to bottom, including a near-infrared transmission layer, a strong reflection layer and an insulating bonding layer. The key pigments or fillers used in each layer were determined by utilizing an indoor irradiation test. The optimal dosage of pigment G, pigment Y, titanium dioxide and floating beads was 3.7%, 3.7%, 15.2% and 16%, respectively. The cooling effect of the proposed coating was investigated by comparing the surface and internal temperature of the coated and uncoated asphalt mixture specimens. Results showed that the strong reflection layer contributed the most to cooling effect, reducing temperature about 8.5 °C–9.5 °C. The internal temperature of specimens coated with FGMC used pigment G and pigment Y decreased by 11.5 °C and 13 °C respectively. Moreover, the skid resistance, water resistance, alkali resistance and abrasive resistance of the proposed coating met the requirements of standards. The proposed coating can reduce temperature and provide a new direction for solar reflective coating of asphalt pavements. [ABSTRACT FROM AUTHOR]

As technology advances, microprocessors that integrate multiple cores on a single chip are becoming increasingly common. How to use these processors to improve the performance of a single program has been a challenge. For general-purpose applications, it is especially difficult to create efficient parallel execution due to the complex control flow and ambiguous data dependences. Thread-level speculation and transactional memory provide two hardware mechanisms that are able to optimistically parallelize potentially dependent threads. However, a compiler that performs detailed performance trade-off analysis is essential for generating efficient parallel programs for these hardwares. This compiler must be able to take into consideration the cost of intra-thread as well as inter-thread value communication. On the other hand, the ubiquitous existence of complex, input-dependent control flow and data dependence patterns in general-purpose applications makes it impossible to have one technique optimize all program patterns. In this paper, we propose three optimization techniques to improve the thread performance: (i) scheduling instruction and generating recovery code to reduce the critical forwarding path introduced by synchronizing memory resident values; (ii) identifying reduction variables and transforming the code the minimize the serializing execution; and (iii) dynamically merging consecutive iterations of a loop to avoid stalls due to unbalanced workload. Detailed evaluation of the proposed mechanism shows that each optimization technique improves a subset but none improve all of the SPEC2000 benchmarks. On average, the proposed optimizations improve the performance by 7% for the set of the SPEC2000 benchmarks that have already been optimized for register-resident value communication. [ABSTRACT FROM AUTHOR]

Schistosomiasis is a neglected tropical disease of humans caused by blood flukes of the genus Schistosoma, the only dioecious parasitic flatworm. Although aspects of sex determination, differentiation and reproduction have been studied in some Schistosoma species, almost nothing is known for Schistosoma japonicum, the causative agent of schistosomiasis japonica. This mainly reflects the lack of high‐quality genomic and transcriptomic resources for this species. As current genomes for S. japonicum are highly fragmented, we assembled and report a chromosome‐level reference genome (seven autosomes, the Z‐chromosome and partial W‐chromosome), achieving a substantially enhanced gene annotation. Utilizing this genome, we discovered that the sex chromosomes of S. japonicum and its congener S. mansoni independently suppressed recombination during evolution, forming five and two evolutionary strata, respectively. By exploring the W‐chromosome and sex‐specific transcriptomes, we identified 35 W‐linked genes and 257 female‐preferentially transcribed genes (FTGs) from our chromosomal assembly and uncovered a signature for sex determination and differentiation in S. japonicum. These FTGs clustering within autosomes or the Z‐chromosome exhibit a highly dynamic transcription profile during the pairing of female and male schistosomula, thereby representing a critical phase for the maturation of the female worms and suggesting distinct layers of regulatory control of gene transcription at this development stage. Collectively, these data provide a valuable resource for further functional genomic characterization of S. japonicum, shed light on the evolution of sex chromosomes in this highly virulent human blood fluke, and provide a pathway to identify novel targets for development of intervention tools against schistosomiasis. [ABSTRACT FROM AUTHOR]

Abstract: Much radiation absorption and accumulation by asphalt pavement result in serious deteriorations of embankment and permafrost along the Qinghai–Tibet Highway (QTH). In order to reduce these adverse effects, a unilateral heat-transfer (UHT) asphalt pavement is proposed in this paper. It is a tri-layered asphalt pavement with a decreasing conductivity from top to bottom. The pavement with such a conductivity gradient has a capability of UHT. Comparative laboratory experiments under lamplight were carried out to validate the UHT capability. The simulation result of summer pavement heat-absorbing showed that, comparing with the contrast group (CG), the temperature under the experimental group (EG) could be reduced by 2.5°C. The simulation result of winter embankment heat-releasing showed that the temperature on the surface of the EG was 1.0°C higher than that on the surface of the CG. The calculation of heat absorption and heat conduction in specimens demonstrated that the EG had a better cooling potential than the CG. These results demonstrate that the CG can not only aid in buffering the radiation heat into the embankment, but also help the accumulated heat to be released outward. If the technology can be applied in permafrost areas, it may provide a positive method to protect the embankment and permafrost. [Copyright &y& Elsevier]

Avian influenza A viruses could get across the species barrier and be fatal to humans. Highly pathogenic avian influenza H5N1 virus was an example. The mechanism of interspecies transmission is not clear as yet. In this research, the protein sequences of 237 influenza A viruses with different subtypes were transformed into pseudo-signals. The energy features were extracted by the method of wavelet packet decomposition and used for virus classification by the method of hierarchical clustering. The clustering results showed that five patterns existed in avian influenza A viruses, which associated with the phenotype of interspecies transmission, and that avian viruses with patterns C and E could across species barrier and those with patterns A, B and D might not have the abilities. The results could be used to construct an early warning system to predict the transmissibility of avian influenza A viruses to humans. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) has been explored actively in luminescent organic materials. Yet, realizing such TADF‐active, multifunctional emitters with high emission efficiency still remains hugely challenging. In this context, a series of twist‐conjugated organic molecules bearing diphenylsulfone and 9,9‐dimethylacridine moieties are designed and prepared, and are found to show, in one molecule, TADF, room‐temperature phosphorescence, triboluminescence, and aggregation‐induced emission enhancement. In addition, remarkably high photoluminescence quantum efficiency, up to ≈100%, is achieved for these novel molecules. Single‐crystal analysis and theoretical calculations reveal that the through‐space charge transfer (TSCT) effect in these molecules is responsible for both the multifunctional emission and high emission efficiency. A maximum external quantum efficiency of 20.1% is achieved, which is among the highest recorded in a solution‐processable device containing TSCT‐based TADF materials. These results illustrate a new approach to achieving highly efficient TADF‐active, multifunctional emitters. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL) is of interest due to its wide potential application in semiconductors. To balance the emission efficiency and luminescence dissymmetry factor (gPL) of a CPL emitter, in this context, two chiral, phosphorescent and liquid‐crystalline cyclometalated platinum complexes, abbreviated R‐Pt and S‐Pt, are prepared. The complexes, which show an intense green emission at 504 nm both in solution and in the solid state, contain a simple, ortho‐metalated 2‐phenylpyridine unit functionalized with a chiral 2‐octanol chain, with liquid crystallinity being induced by modifying the β‐diketonato ligand with mesogenic groups. Interestingly, both the chiral smectic (SmA*) and nematic (N*) phases are found by a combination of polarized optical microscopy, differential scanning calorimetry, and small‐angle X‐ray scattering. By annealing, distinct CPL emission is achieved in the solid state with a gPL around 0.02. Employing the chiral platinum complexes as the dopant, solution‐processable organic light‐emitting diodes present an external quantum efficiency of 11.3% and strong, circularly polarized electroluminescence with an extremely high luminescence dissymmetry value (gEL) of 0.06 after annealing at 100 °C. This work opens an avenue for designing CPL‐active emitters with high emission efficiency and high dissymmetry factor. [ABSTRACT FROM AUTHOR]

Artemisia annua , commonly known as sweet wormwood or Qinghao, is a shrub native to China and has long been used for medicinal purposes. A . annua is now cultivated globally as the only natural source of a potent anti-malarial compound, artemisinin. Here, we report a high-quality draft assembly of the 1.74-gigabase genome of A . annua , which is highly heterozygous, rich in repetitive sequences, and contains 63 226 protein-coding genes, one of the largest numbers among the sequenced plant species. We found that, as one of a few sequenced genomes in the Asteraceae, the A . annua genome contains a large number of genes specific to this large angiosperm clade. Notably, the expansion and functional diversification of genes encoding enzymes involved in terpene biosynthesis are consistent with the evolution of the artemisinin biosynthetic pathway. We further revealed by transcriptome profiling that A . annua has evolved the sophisticated transcriptional regulatory networks underlying artemisinin biosynthesis. Based on comprehensive genomic and transcriptomic analyses we generated transgenic A . annua lines producing high levels of artemisinin, which are now ready for large-scale production and thereby will help meet the challenge of increasing global demand of artemisinin. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor (VEGF) plays critical roles in angiogenesis and vasculogenesis, which are associated with post-stroke functional recovery. However, the effects of the VEGFA polymorphisms on the outcome of ischemic stroke (IS) have been rarely reported. We therefore investigated the associations of +936C/T variant (rs3025039) with the susceptibilities and the 90-day outcomes from 494 IS patients and 337 healthy controls in Chinese population through the establishment of logistic multivariate regression model. Stroke severity at admission and outcome of 90 days were respectively assessed according to the National Institutes of Health Stroke Scale and the modified Rankin Scale. The analysis showed that there were no significant associations of the rs3025039 genotypes with the susceptibility (P = 0.229) and the severity (P = 0.734). However, when we divided the 308 IS patients into two groups according to the different outcomes, we found that the rs3025039 TC+TT genotype significantly increased the risk of poor recovery [adjusted odds ratio (OR), 1.99; 95% confidence interval (CI), 1.18–3.37]. Interestingly, we observed another 3ˈUTR variant, +1451C/T (rs3025040), exhibited strong linkage disequilibrium (r2 = 1.0) with +936C/T and was located in a predicted microRNA-binding site. The rs3025040 T allele significantly decreased the luciferase activities in four cell lines, which indicated a potential disruption of the miRNA-mRNA interaction that would result in lower VEGF expression levels. Our data suggested that the +936C/T variants significantly increased the risk of poorer stroke outcome by affecting the bindings of miR-199a and miR-199b to VEGF mRNA at the rs30250340 polymorphic site. [ABSTRACT FROM AUTHOR]

Diverse cellulolytic bacteria are essential for maintaining high lignocellulose degradation ability in biogas digesters. However, little was known about functional genes and gene clusters of dominant cellulolytic bacteria in biogas digesters. This is the foundation to understand lignocellulose degradation mechanisms of biogas digesters and apply these gene resource for optimizing biofuel production. A combination of metagenomic and 16S rRNA gene clone library methods was used to investigate the dominant cellulolytic bacteria and their glycoside hydrolase (GH) genes in two biogas digesters. The 16S rRNA gene analysis revealed that the dominant cellulolytic bacteria were strains closely related to Clostridium straminisolvens and an uncultured cellulolytic bacterium designated BG-1. To recover GH genes from cellulolytic bacteria in general, and BG-1 in particular, a refined assembly approach developed in this study was used to assemble GH genes from metagenomic reads; 163 GH-containing contigs ≥ 1 kb in length were obtained. Six recovered GH5 genes that were expressed in E. coli demonstrated multiple lignocellulase activities and one had high mannanase activity (1255 U/mg). Eleven fosmid clones harboring the recovered GH-containing contigs were sequenced and assembled into 10 fosmid contigs. The composition of GH genes in the 163 assembled metagenomic contigs and 10 fosmid contigs indicated that diverse GHs and lignocellulose degradation mechanisms were present in the biogas digesters. In particular, a small portion of BG-1 genome information was recovered by PhyloPythiaS analysis. The lignocellulase gene clusters in BG-1 suggested that it might use a possible novel lignocellulose degradation mechanism to efficiently degrade lignocellulose. Dominant cellulolytic bacteria of biogas digester possess diverse GH genes, not only in sequences but also in their functions, which may be applied for production of biofuel in the future. [ABSTRACT FROM AUTHOR]

Abstract: Pavement surface characteristics are major attributes to tire/pavement interactions and are considered as cost-effective options to mitigate traffic noise. The objective of this paper is to evaluate the effects of single and multiple pavement surface characteristics on tire/pavement noise levels. During the period from August 2009 to August 2011, noise levels and pavement surface characteristics are measured quarterly on impervious and open-graded asphalt pavements at 2009 NCAT test track. The linear regression analysis method and dominance analysis method are used to evaluate the effects of single and multiple pavement surface characteristics on noise levels, respectively. The results show that surface texture increases noise levels at lower frequencies (below 1600Hz) especially on impervious asphalt pavements. Porosity decreases noise levels at every frequency (except at 2500Hz) on open-graded asphalt pavements. These findings will help to design future low-noise asphalt pavements. [Copyright &y& Elsevier]

In this study, 341, 246, and 386 positive clones with endo-β-1,4-glucanase, β-glucosidase, and endo-β-1,4-xylanase activities, respectively, were identified by screening from a metagenomic fosmid library constructed from a biogas digester. Subsequently, pools of 4, 10, and 16 positive clones were subjected to 454 pyrosequencing in different subruns. In total, 21 unique glycosyl hydrolase (GH) genes were predicted by bioinformatic analysis, which showed similarities to their nearest neighbors from 39 % to 72 %. In addition to bioinformatics prediction, nine GH genes were expressed and purified to identify their activity with four kinds of substrates. The activities of the most expressed proteins were consistent with their annotation based on bioinformatics prediction; however, three GH genes belonging to the GH5 family showed different activities from their annotation. An efficient acidic cellulase En1 had an optimal condition at 55 °C, pH 5.5, with a specific activity toward carboxymethylcellulose at 118 U/mg and K at 12.8 g/L. This study demonstrated that there are diverse GHs in the biogas digester system with potential industrial application in lignocellulose hydrolysis, and their activities should be investigated with different substrates before their application. Additionally, pool sequencing of positive fosmid clones might be a cost-effective approach to obtain functional genes from metagenomic libraries. [ABSTRACT FROM AUTHOR]

The human gut microbiota is a complex system that is essential to the health of the host. Increasing evidence suggests that the gut microbiota may play an important role in the pathogenesis of colorectal cancer (CRC). In this study, we used pyrosequencing of the 16S rRNA gene V3 region to characterize the fecal microbiota of 19 patients with CRC and 20 healthy control subjects. The results revealed striking differences in fecal microbial population patterns between these two groups. Partial least-squares discriminant analysis showed that 17 phylotypes closely related to Bacteroides were enriched in the gut microbiota of CRC patients, whereas nine operational taxonomic units, represented by the butyrate-producing genera Faecalibacterium and Roseburia, were significantly less abundant. A positive correlation was observed between the abundance of Bacteroides species and CRC disease status ( R = 0.462, P = 0.046 < 0.5). In addition, 16 genera were significantly more abundant in CRC samples than in controls, including potentially pathogenic Fusobacterium and Campylobacter species at genus level. The dysbiosis of fecal microbiota, characterized by the enrichment of potential pathogens and the decrease in butyrate-producing members, may therefore represent a specific microbial signature of CRC. A greater understanding of the dynamics of the fecal microbiota may assist in the development of novel fecal microbiome-related diagnostic tools for CRC. [ABSTRACT FROM AUTHOR]

Macrotermitinae (fungus-cultivating termites) are major decomposers in tropical and subtropical areas of Asia and Africa. They have specifically evolved mutualistic associations with both a Termitomyces fungi on the nest and a gut microbiota, providing a model system for probing host-microbe interactions. Yet the symbiotic roles of gut microbes residing in its major feeding caste remain largely undefined. Here, by pyrosequencing the whole gut metagenome of adult workers of a fungus-cultivating termite (Odontotermes yunnanensis), we showed that it did harbor a broad set of genes or gene modules encoding carbohydrate-active enzymes (CAZymes) relevant to plant fiber degradation, particularly debranching enzymes and oligosaccharide-processing enzymes. Besides, it also contained a considerable number of genes encoding chitinases and glycoprotein oligosaccharide-processing enzymes for fungal cell wall degradation. To investigate the metabolic divergence of higher termites of different feeding guilds, a SEED subsystem-based gene-centric comparative analysis of the data with that of a previously sequenced wood-feeding Nasutitermes hindgut microbiome was also attempted, revealing that SEED classifications of nitrogen metabolism, and motility and chemotaxis were significantly overrepresented in the wood-feeder hindgut metagenome, while Bacteroidales conjugative transposons and subsystems related to central aromatic compounds metabolism were apparently overrepresented here. This work fills up our gaps in understanding the functional capacities of fungus-cultivating termite gut microbiota, especially their roles in the symbiotic digestion of lignocelluloses and utilization of fungal biomass, both of which greatly add to existing understandings of this peculiar symbiosis. [ABSTRACT FROM AUTHOR]

Volvariella volvacea, the edible straw mushroom, is a highly nutritious food source that is widely cultivated on a commercial scale in many parts of Asia using agricultural wastes (rice straw, cotton wastes) as growth substrates. However, developments in V. volvacea cultivation have been limited due to a low biological efficiency (i.e. conversion of growth substrate to mushroom fruit bodies), sensitivity to low temperatures, and an unclear sexuality pattern that has restricted the breeding of improved strains. We have now sequenced the genome of V. volvacea and assembled it into 62 scaffolds with a total genome size of 35.7 megabases (Mb), containing 11,084 predicted gene models. Comparative analyses were performed with the model species in basidiomycete on mating type system, carbohydrate active enzymes, and fungal oxidative lignin enzymes. We also studied transcriptional regulation of the response to low temperature (4°C). We found that the genome of V. volvacea has many genes that code for enzymes, which are involved in the degradation of cellulose, hemicellulose, and pectin. The molecular genetics of the mating type system in V. volvacea was also found to be similar to the bipolar system in basidiomycetes, suggesting that it is secondary homothallism. Sensitivity to low temperatures could be due to the lack of the initiation of the biosynthesis of unsaturated fatty acids, trehalose and glycogen biosyntheses in this mushroom. Genome sequencing of V. volvacea has improved our understanding of the biological characteristics related to the degradation of the cultivating compost consisting of agricultural waste, the sexual reproduction mechanism, and the sensitivity to low temperatures at the molecular level which in turn will enable us to increase the industrial production of this mushroom. [ABSTRACT FROM AUTHOR]

Many Penicillium species could produce extracellular enzyme systems with good lignocellulose hydrolysis performance. However, these species and their enzyme systems are still poorly understood and explored due to the lacking of genetic information. Here, we present the genomic and secretomic analyses of Penicillium decumbens that has been used in industrial production of lignocellulolytic enzymes in China for more than fifteen years. Comparative genomics analysis with the phylogenetically most similar species Penicillium chrysogenum revealed that P. decumbens has evolved with more genes involved in plant cell wall degradation, but fewer genes in cellular metabolism and regulation. Compared with the widely used cellulase producer Trichoderma reesei, P. decumbens has a lignocellulolytic enzyme system with more diverse components, particularly for cellulose binding domain-containing proteins and hemicellulases. Further, proteomic analysis of secretomes revealed that P. decumbens produced significantly more lignocellulolytic enzymes in the medium with cellulose-wheat bran as the carbon source than with glucose. The results expand our knowledge on the genetic information of lignocellulolytic enzyme systems in Penicillium species, and will facilitate rational strain improvement for the production of highly efficient enzyme systems used in lignocellulose utilization from Penicillium species. [ABSTRACT FROM AUTHOR]

Background. Drug-resistant tuberculosis poses a growing challenge to global public health. However, the diversity and dynamics of the bacterial population during acquisition of drug resistance have yet to be carefully examined.Methods. Whole-genome sequencing was performed on 7 serial Mycobacterium tuberculosis (M. tuberculosis) populations from 3 patients during different stages in the development of drug resistance. The population diversity was assessed by the number and frequencies of unfixed mutations in each sample.Results. For each bacterial population, 8–41 unfixed mutations were monitored by the fraction of single-nucleotide polymorphisms at specific loci. Among them, as many as 4 to 5 resistance-conferring mutations were transiently detected in the same single sputum, but ultimately only a single type of mutant was fixed. In addition, we identified 14 potential compensatory mutations that occurred during or after the emergence of resistance-conferring mutations.Conclusions. M. tuberculosis population within patients exhibited considerable genetic diversity, which underwent selections for most fit resistant mutant. These findings have important implications and emphasize the need for early diagnosis of tuberculosis to decrease the chance of evolving highly fit drug-resistant strains. [ABSTRACT FROM AUTHOR]

Abstract: The symbiotic protists in the hindgut of lower termites are critical for lignocellulose decomposition. Due to the unculturability of these protists, information on lignocellulases and their abundance within the gut is unavailable. The advent of high-throughput sequencing technologies enables an investigation of the gene expression profile in this community without culturing these organisms. Here, we carried out 454 pyrosequencing to profile the metatranscriptome of the protistan community in Coptotermes formosanus. In total, 223,477 reads were obtained by sequencing the enriched protistan mRNA. Phagocytosis and cytoskeletal homeostasis pathways were highly represented in the metatranscriptome. Among the metabolic pathways, starch and sucrose metabolism were dominant. A detailed analysis combining Pfam and KEGG annotation identified 118 glycosyl hydrolases belonging to 18 different glycosyl hydrolase families (GHFs). Subsequently, a novel GHF10 endo-1,4-beta-xylanase was functionally characterized to complement our understanding of the protistan hemicellulases. [Copyright &y& Elsevier]

In this study, the 454 pyrosequencing technology was used to analyze the DNA of the Microcystis aeruginosa symbiosis system from cyanobacterial algal blooms in Taihu Lake, China. We generated 183 228 reads with an average length of 248 bp. Running the 454 assembly algorithm over our sequences yielded 22 239 significant contigs. After excluding the M. aeruginosa sequences, we obtained 1 322 assembled contigs longer than 1 000 bp. Taxonomic analysis indicated that four kingdoms were represented in the community: Archaea ( n = 9; 0.01%), Bacteria ( n = 98 921; 99.6%), Eukaryota ( n = 373; 3.7%), and Viruses ( n = 18; 0.02%). The bacterial sequences were predominantly Alphaproteobacteria ( n = 41 805; 83.3%), Betaproteobacteria ( n = 5 254; 10.5%) and Gammaproteobacteria ( n = 1 180; 2.4%). Gene annotations and assignment of COG (clusters of orthologous groups) functional categories indicate that a large number of the predicted genes are involved in metabolic, genetic, and environmental information processes. Our results demonstrate the extraordinary diversity of a microbial community in an ectosymbiotic system and further establish the tremendous utility of pyrosequencing. [ABSTRACT FROM AUTHOR]

Abstract: We genotyped (using 16 or 17 microsatellite loci) numerous adult Schistosoma japonicum raised in rabbits exposed to pooled cercariae from small numbers of naturally infected snails from several localities in China. As expected, duplicate multi-locus genotypes (MLGs) were found among these worms. Additionally, many more MLGs, often near-identical, were found than snails used as sources of cercariae. Explanations for these results include (i) genotyping errors, (ii) development within each infected snail of multiple sibling miracidia and (iii) somatic mutation producing genetically varied cercariae from a single miracidium. To control for genotyping errors we re-analysed samples from many individual worms, including repeating the initial PCR. Explanations invoking the development of multiple sibling miracidia within a single snail are not likely to be correct because almost all duplicate MLGs fell within same-sex clusters in a principal coordinates analysis. We would expect both sexes to be represented in a multi-miracidium infection. In addition, we exposed several snails to infection by a single miracidium. One such snail, via an experimentally infected mouse, yielded 48 adult worms. The presence of at least nine near-identical MLGs among these worms was confirmed by re-genotyping. We regard somatic mutation as the most likely explanation for our results. The implications of multiple MLGs for population-genetic studies in S. japonicum are discussed. [Copyright &y& Elsevier]

Rice is the principal food for over half of the population of the world. With its genome size of 430 megabase pairs (Mb), the cultivated rice species Oryza sativa is a model plant for genome research. Here we report the sequence analysis of chromosome 4 of O. sativa, one of the first two rice chromosomes to be sequenced completely. The finished sequence spans 34.6 Mb and represents 97.3% of the chromosome. In addition, we report the longest known sequence for a plant centromere, a completely sequenced contig of 1.16 Mb corresponding to the centromeric region of chromosome 4. We predict 4,658 protein coding genes and 70 transfer RNA genes. A total of 1,681 predicted genes match available unique rice expressed sequence tags. Transposable elements have a pronounced bias towards the euchromatic regions, indicating a dose correlation of their distributions to genes along the chromosome. Comparative genome analysis between cultivated rice subspecies shows that there is an overall syntenic relationship between the chromosomes and divergence at the level of single-nucleotide polymorphisms and insertions and deletions. By contrast, there is little conservation in gene order between rice and Arabidopsis. [ABSTRACT FROM AUTHOR]

Four crucifix‐shaped molecules, named TPA‐BPSB, DMAc‐BPSB, MTPA‐BPSB and MDMAc‐BPSB, bearing the same acceptor fragment of bis(phenylsulfonyl)benzene (BPSB) and different donor segments (TPA and MTPA are the diphenylamine derivatives while DMAc and MDMAc are the 9,9‐dimethylacridine derivatives) are synthesized and characterized by NMR, mass spectra, and single crystal X‐ray crystallography. The molecular structure–property relationship of these crucifix‐shaped molecules is systematically explored. All compounds display thermally activated delayed fluorescence (TADF) in the region of 500–550 nm. In addition, charming mechanochromic luminescence properties are observed for all these TADF molecules under external stimuli, such as grinding and exposure to CH2Cl2 vapor. Four TADF molecules are used as the emitters in organic light‐emitting diodes (OLEDs) fabricated via solution process. MTPA‐BPSB‐based device presents a best performance with a highest external quantum efficiency of ≈21%, which is among the highest efficiencies for reported BPSB‐based solution‐processable OLEDs so far. This research has an important significance in designing high‐efficiency multifunctional TADF molecules. [ABSTRACT FROM AUTHOR]

Reverse transcriptase (RT) mutations contribute to hepatitis B virus resistance during antiviral therapy with nucleos(t)ide analogs. However, the composition of the RT quasispecies and their interactions during antiviral treatment have not yet been thoroughly defined. In this report, 10 patients from each of 3 different virological response groups, i.e., complete virological response, partial virological response and virological breakthrough, were selected from a multicenter trial of Telbivudine treatment. Variations in the drug resistance-related critical RT regions in 107 serial serum samples from the 30 patients were examined by ultra-deep sequencing. A total of 496,577 sequence reads were obtained, with an average sequencing coverage of 4,641X per sample. The phylogenies of the quasispecies revealed the independent origins of two critical quasispecies, i.e., the rtA181T and rtM204I mutants. Data analyses and theoretical modeling showed a cooperative-competitive interplay among the quasispecies. In particular, rtM204I mutants compete against other quasispecies, which eventually leads to virological breakthrough. However, in the absence of rtM204I mutants, synergistic growth of the drug-resistant rtA181T mutants with the wild-type quasispecies could drive the composition of the viral population into a state of partial virological response. Furthermore, we demonstrated that the frequency of drug-resistant mutations in the early phase of treatment is important for predicting the virological response to antiviral therapy. [ABSTRACT FROM AUTHOR]