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Using a high-throughput sequencing (HTS) approach, we report the discovery of a new alphasatellite identified in a winter barley plant collected in France in 2022 that was also infected by wheat dwarf virus (WDV). The presence of the satellite and of WDV was confirmed by several independent PCR assays, and the complete genome sequence was determined. The circular satellite genome is 1424 nt long and shows typical hallmarks of members of the subfamily Geminialphasatellitinae, including a replication-associated hairpin with a CAGTATTAC sequence and a Rep-encoding open reading frame (ORF). It also possesses a second ORF, embedded in a different frame within the Rep ORF, which is also observed in clecrusatellites and a few other members of the family Alphasatellitidae. Pairwise sequence comparisons and phylogenetic analysis showed that this satellite represents a novel species. Its closest relatives are in the genus Colecusatellite, but it likely represents a new genus given its divergence from other genera of the subfamily Geminialphasatellitinae. Given that WDV was the only virus observed in coinfection with the satellite, the name "wheat dwarf virus-associated alphasatellite" is proposed for this novel agent. [ABSTRACT FROM AUTHOR]

Using animate nouns to refer to entities in the world involves a complex interaction of ontology, cognition and language. The present study evaluates two accounts of the use of animate nouns, with Mandarin Chinese as the vehicle for testing between the competing accounts. One account was proposed by Cheng et al. (2008. How universal is the Universal Grinder? In Marjo van Koppen & Bert Botma (eds.), Linguistics in the Netherlands, 50–62. Amsterdam & Philadelphia: John Benjamins). These researchers contend that the count interpretation is basic for Mandarin animate nouns, due to a lexical blocking effect. To access the alternative, mass interpretation requires some kind of pragmatic coercion. A second account was proposed by Pelletier, based on English (1975. Non-Singular reference: Some preliminaries. Philosophia 5(4). 451–465; 2012. Lexical nouns are both +MASS and +COUNT, but they are neither +MASS nor + COUNT. In Diane Massam (ed.), Count and mass across languages, 9–26. Oxford: Oxford University Press). We extend this account to Mandarin animate nouns, proposing that they are encoded in the mental lexicon with both a count sense and a mass sense. To adjudicate between the accounts, we conducted four experiments that were designed to assess the interpretation assigned to animate nouns by Mandarin-speaking children and adults. The experimental conditions manipulated both the syntactic structures of the sentences and the non-linguistic contexts in which those sentences were presented. The experimental findings support our proposal that both mass and count interpretations of animate nouns are available to children and adults when sentences are presented in contexts that are congruent with these interpretations. The findings also suggest that syntactic structure is an even more critical factor in determining the interpretation that is assigned to animate nouns in Mandarin. [ABSTRACT FROM AUTHOR]

Oxide dispersion strengthened (ODS) nickel (Ni)‐based superalloys are advanced materials known for their outstanding tensile and creep performance at temperatures exceeding 1000 °C. Nevertheless, their conventional synthesis presents a longstanding challenge in cost‐effectively producing intricate components for critical applications. In this work, electrostatic self‐assembly (ESA) of powders with the laser powder bed fusion (LPBF) process are successfully combined to produce yttria ODS Inconel 718 (IN718) alloy for the first time. This approach demonstrates a significant contribution of yttria to the strength of IN718 after the solid solution heat treatment, as evidenced by ≈50% improvement in room temperature yield strength with a 0.5 wt.% yttria addition. The addition of yttria by this process leads to a heterogeneous microstructure. This heterogeneous microstructure comprises two distinct grain areas with varying amounts of yttria nanoparticles and dislocation storage. The results show that the yield strength increase can be predicted by the combination of both Y2O3 dispersion strengthening and dislocation strengthening mechanisms. These findings offer an effective approach to tailor heterogeneous microstructures, unlocking new opportunities for cost‐effectively producing high‐performance ODS Ni‐based superalloy products with excellent mechanical properties. [ABSTRACT FROM AUTHOR]

The Asian citrus psyllid (ACP) is the main vector of Citrus Huanglongbing, the most damaging citrus disease, causing significant financial losses in the citrus industry. Global warming has expanded the habitat of this pest, allowing it to continue its northward migration to China. Population genetic information of ACP is fundamentally essential for species management. This study investigated the genetic diversity and population structure of Chinese ACP using the mitochondrial cytochrome oxidase subunit I gene by dataset comprised 721 sequences from 27 geographic sites in China. Low haplotype diversity (0.323 ± 0.022) and low nucleotide diversity (0.00071 ± 0.00007) were observed in the entire population, which may indicate recent founder events. Twenty-three haplotypes were identified and clustered into 2 haplogroups: haplogroup I and haplogroup II. Haplogroup II included only 2 unique haplotypes, which occurred exclusively in the Southwest China ACP population. Genetic differentiation analyses were also indicative of Southwest China population was significantly differentiated from the remaining populations. Demographic history analysis showed that ACP population in China has experienced demographic expansion. Our results provided a better understanding of the genetic distribution patterns and structures of ACP populations in China. [ABSTRACT FROM AUTHOR]

Platform heating is one of the effective strategies used in laser powder bed fusion (LPBF) to avoid cracking during manufacturing, especially when building relatively large-size components, as it removes significant process-induced residual strains. In this work, we propose a novel and simple method to spare the elaborate post-processing heat treatment typically needed for LPBF Al-Sc alloys without compromising the mechanical properties. We systematically investigated the effects of LPBF platform heating at 200 °C on the residual stress relief, microstructure, and mechanical performance of a high-strength Al-Mn-Sc alloy. The results reveal that LPBF platform heating at 200 °C is sufficient to largely relieve the process-induced residual stresses compared to parts built on an unheated 35 °C platform. Meanwhile, the platform heating triggered the dynamic precipitation of uniformly dispersed (1.5–2 nm) Sc-rich nano-clusters. Their formation in a high number density (1.75 × 1024 m−3) resulted in a ~20% improvement in tensile yield strength (522 MPa) compared to the build on the unheated platform, without sacrificing the ductility (up to 18%). The improved mechanical properties imply that platform heating at 200 °C can strengthen the LPBF-synthesised Sc-containing Al alloys via in situ aging, which is further justified by an in situ measurement study revealing that the developing temperatures in the LPBF part are within the aging temperature range of Al-Sc alloys. Without any post-LPBF treatments, these mechanical properties have proven better than those of most Al-Sc alloys through long-time post-LPBF heat treatment. [ABSTRACT FROM AUTHOR]

A Laser Powder Bed Fusion Inconel 718 produced with intentionally non‐optimized parameters is investigated to understand the role of defects and microstructure on the high‐cycle fatigue life. Samples from three built directions and three heat treatments were used for fatigue tests at room and 650°C under R=0.1. Printing orientation has a minor effect on fatigue life at both temperatures. Most samples failed from lack of fusion defects, carefully analyzed by scanning electron microscope (SEM) observations. Surface defect leads to transgranular fracture surface, while subsurface initiation leads to crystallographic fracture surface. S−N curves related to hot isostatic pressure condition shown that defects have higher influence at 20°C than at 650°C. Kitagawa diagrams are plotted for both temperatures to quantify the influence of defect size on fatigue limit. Natural cracks are observed at the surface in order to discuss the relative part of initiation life in the whole fatigue life. Highlights: Fatigue is governed by lack of fusion (LoF) ranging from 200 to 600 μmThe fatigue limit is higher at high temperature compared with ambient temperatureHot isostatic pressure (HIP) treatment improves the fatigue resistanceNatural crack initiated from LoF propagates in a very similar way compared with long crack [ABSTRACT FROM AUTHOR]

Laser powder bed fusion (LPBF) is an outstanding additive manufacturing (AM) technology that can enable both complicated geometries and desired mechanical properties in high-value components. However, the process reliability and cost have been the obstacles to the extensive industrial adoptions of LPBF. This work aims to develop a powder recycling procedure to reduce production cost and minimize process uncertainties due to powder degradation. We used a recycle index (R) to reuse Ti-6Al-4V powder through 10 production cycles. Using this recycle index is more reasonable than simply replying on recycle numbers as it incorporates the powder usage history. A recycling procedure with simple virgin powder top-up can effectively mitigate powder degradation and maintain stable powder properties, chemical compositions, and tensile properties. The experimental finding points to a sustainable recycling strategy of Ti alloy powders with minimal material waste and without noticeable detriment to observed mechanical performance through LPBF production cycles. [ABSTRACT FROM AUTHOR]

Metal ion doping is the most widely used means to improve the photocatalytic performance of semiconductor materials, which can adjust the band gap, broaden the range of optical response and construct impurity levels. The high efficiency modified NaTaO3 perovskite catalyst with good structural and catalytic properties was synthesized by a simple hydrothermal reaction method. A variety of analysis and testing techniques, such as XRD, SEM, DRS, XPS and EPR, were used to analyze the structure properties of the prepared materials. The results show that the influence mechanism of different metal introduction on the structure and properties of the NaTaO3 perovskite was different. Metal doping promoted the bond angle of Ta-O-Ta close to 180°, which restrains the recombination of the photogenerated electron-holes in the crystal. As Ce is introduced into the perovskite, the CeO2 forms and agglomerates around the perovskite, which improves the electron transport performance. With the narrower band gap, the Ce-modified perovskite shows that the degradation rate of ARS is 84% after 180 min of photoreaction. The species of h+, O2− and ·OH play different roles in improving the performance of the photocatalytic degradation process. [ABSTRACT FROM AUTHOR]

Huanglongbing (HLB) is a plant disease mainly spread by the insect-borne citrus psyllid. It is the most destructive citrus pathosystem worldwide. To understand the impact of sexual transmission on HLB dynamics, we propose a host–vector–HLB compartment model incorporating two transmission routes. The basic reproduction number ℛ 0 is derived. Various interventions of the disease are assessed. We also investigate the effect of different incidence functions to simulate sexual transmission. For the case of sublinear incidence functions, the disease-free equilibrium is globally asymptotically stable (GAS) provided ℛ 0 < 1. For mass action incidence of sexual transmission, the endemic equilibrium is GAS provided ℛ 0 > 1. However, under nonlinear incidence, it is proved that the model may exhibit backward bifurcation. Theoretical and numerical studies reveal that (i) different forces of infection between heterosexual psyllids in the model may have a distinct impact on disease dynamics; (ii) sensitivity analysis shows that for ℛ 0 , the transmission rate between host and vector is more sensitive parameter than that between heterosexual psyllids; (iii) if the sexual transmission is ignored, the disease burden is likely to be underestimated in comparison with realistic scenarios; (iv) in the absence of chemical insecticides, the combined use of yellow sticky traps and injection of nutrient solutions can be more effective in suppressing the spread of HLB. These findings provide valuable insights for public policymakers to determine the long-term viability of implemented HLB management strategies and highlight the urgency of finding sustainable HLB solutions. [ABSTRACT FROM AUTHOR]

In addition to the common stable and metastable phases in titanium alloys, the face-centered cubic phase was recently observed under various conditions; however, its formation remains largely unclarified. In this work, the effect of nonmetallic interstitial atoms O, N, C and B on the formation of the face-centered cubic phase of titanium was investigated with the density functional theory. The results indicate that the occupancy of O, N, C and B on the octahedral interstitial sites reduces the energy gap between the hexagonal-close-packed (HCP) and face-centered cubic (FCC) phases, thus assisting the formation of FCC-Ti under elevated temperature or plastic deformation. Such a gap further decreases with the increase in the interstitial content, which is consistent with the experimental observation of FCC-Ti under high interstitial content. The relative stability of the interstitial-containing HCP-Ti and FCC-Ti was studied against the physical and chemical origins, e.g., the lattice distortion and the electronic bonding. Interstitial O, N, C and B also reduce the stacking fault energy, thus further benefiting the formation of FCC-Ti. [ABSTRACT FROM AUTHOR]

This study investigates the effect of microstructure on short-term and long-term oxidation behaviours of GH3536 superalloy fabricated by laser powder bed fusion (LPBF), in which the superalloy is isothermally oxidised at 950 °C for 6 h and 500 h in air. The LPBF sample exhibits improved oxidation resistance compared with a wrought counterpart after long-term exposure. The effect of microstructure diversity between LPBF and wrought samples on oxidation behaviour is discussed. The cellular structure produced during the LPBF process acts as a rapid diffusion path to accelerate the formation of a protective film in the initial stage, leading to an enhancement in oxidation resistance for extended exposure. [ABSTRACT FROM AUTHOR]

Taking into account the complexity involved in the issue of superordinates, the present study investigates superordinates and their interpretation in Mandarin, as compared to the interpretation of superordinates in English, which is a typical language with number marking. Thus, Mandarin superordinates are mostly used in bare forms; furthermore, Mandarin superordinates are used much more often with mass classifiers than count classifiers. 5 Our account on Mandarin superordinates Our account follows from the grammatical account proposed in the literature for the interpretation of Mandarin nouns in general (e.g., [11]; [31]; [32]; [39]; [49]). Keywords: child language; count-mass semantics; Mandarin Chinese; superordinate collectives EN child language count-mass semantics Mandarin Chinese superordinate collectives 933 972 40 07/05/22 20220701 NES 220701 1 Introduction The study of superordinate collectives has been the subject of much debate in the literature. [Extracted from the article]

Ti-23Nb-0.7Ta-(0, 2)Zr-(1.2, 4, 6, 10)O alloys were prepared using a non-consumable arc-melting method. The tensile property of Ti-23Nb-0.7Ta-2Zr-1.2O alloys was tested at temperatures from −196 °C to 750 °C. The influence of O and Zr contents on thermal forgeability, room-temperature hardness and tensile property at 750 °C was investigated. For Ti-23Nb-0.7Ta-2Zr-1.2O alloy, the tensile strength decreased, and the ductility increased with the temperature increase. O and Zr had a negative effect on the thermal forgeability. Room-temperature hardness and tensile strength increased with an increase in O and Zr contents due to interstitial, solid solution strengthening and second-phase strengthening. All of the alloys exhibited high ductility at 750 °C with the total elongation above 34% and reductions in area above 80%. [ABSTRACT FROM AUTHOR]

Laser powder bed fusion (LPBF) is an emerging additive manufacturing technique that is currently adopted by a number of industries for its ability to directly fabricate complex near-net-shaped components with minimal material wastage. Two major limitations of LPBF, however, are that the process inherently produces components containing some amount of porosity and that fabricated components tend to suffer from poor repeatability. While recent advances have allowed the porosity level to be reduced to a minimum, consistent porosity-free fabrication remains elusive. Therefore, it is important to understand how porosity affects mechanical properties in alloys fabricated this way in order to inform the safe design and application of components. To this aim, this article will review recent literature on the effects of porosity on tensile properties, fatigue life, impact and fracture toughness, creep response, and wear behavior. As the number of alloys that can be fabricated by this technology continues to grow, this overview will mainly focus on four alloys that are commonly fabricated by LPBF—Ti-6Al-4 V, Inconel 718, AISI 316L, and AlSi10Mg. [ABSTRACT FROM AUTHOR]

Transition metal Fe, Co, Ni and Cu doped strontium titanate‐rich SrTiO3@TiO2 (STO@T) materials were prepared by hydrothermal method. The prepared doped materials exhibit better photocatalytic CO2 reduction to CH4 ability under visible light conditions. Among them, Fe‐doped and undoped SrTiO3@TiO2 under visible light conditions CO2 reduction products only CO, while M‐STO@T (M=Co, Ni, Cu) samples converted CO2 to CH4. The average methane yield of Ni‐doped STO@T samples are as high as 73.85 μmol g−1 h−1. The production of methane is mainly due to the increase in the response of the doped samples to visible light. And the increase in the separation rate of photogenerated electrons and holes and the efficiency of electron transport caused by the generation of impurity levels. The impurity level caused by Ti3+ plays an important role in the production of methane by CO2 visible light reduction. Ni doping effectively improves the photocatalytic performance of STO@T and CO2 reduction mechanism were explained. [ABSTRACT FROM AUTHOR]

In this study, the influence that porosities play on the mechanical properties of Ti-6Al-4V parts fabricated by laser powder bed fusion (LPBF) was investigated with the aim of improving process efficiency of the LPBF process by establishing the resulting trade-offs to component quality. It was found that build times can be substantially reduced by using higher layer thickness parameters without a significant detriment to mechanical properties. Where porosities formed, spherical pores tend to have a marginal effect on Young's modulus, yield strength, tensile strength, and uniform elongation as these properties can be approximated linearly using the rule of mixtures assuming null strength pores. However, such pores were found to be otherwise more detrimental to total elongation and toughness. Conversely, lack of fusion pores are extremely detrimental and should be avoided. Thus, it is proposed that when building a component, different process parameters can be used at different regions of the component to maximize process efficiency without compromising its overall function. For instance, for surfaces, a highly optimized parameter set with lower layer thickness can be used. At regions with minimal stress distribution during service, a large layer thickness parameter set where the resulting mechanical properties is sufficient can be used. [ABSTRACT FROM AUTHOR]

In this work, the effects of post-LPBF (laser powder bed fusion) heat treatments on microstructure evolution, tensile and Charpy properties of Ti-6Al-4V have been investigated. The results show that the original martensitic microstructure in the LPBF sample has converted to a lamellae mixture of α and β phases when post heat-treatment temperatures are below the β-transus (800°C, 850°C and 900°C) with air cooling. On this basis, a good balance of tensile strength and ductility was obtained from sample post heated at 800°C for 6 h followed by air-cooling, with an increase of ~42% in ductility and a significant toughness enhancement (almost 100% increase) compared to the as-built sample. The relationship betweenα lamellaethickness, β volume fraction and post-LPBF heat treatment has been established. Both α lamellae thickness and β volume fraction increase with the heat-treatment temperature. [ABSTRACT FROM AUTHOR]

A novel coaxial electron beam wire feeding additive manufacturing technology (CAEBWAM) was proposed in our previous work to refine the microstructure and improve the mechanical properties of titanium alloys. In the present work, different post-heat treatments were performed to understand the microstructure evolution and the resultant mechanical properties of CAEBWAMed Ti-6Al-4V alloy. The as-built sample was dominated by equiaxed prior β microstructure, with the first several deposited layers containing columnar prior β grain morphology. The as-built alloy showed a mixed microstructure composed of large α′ martensite and fine α + β lamella. As the annealing temperature was increased, α′ martensite decomposed into α + β phase, while the width of the α lamellae increased, causeing an increase in the ductility and a decrease in the strength. [ABSTRACT FROM AUTHOR]

The long production time required for large-scale parts fabricated by laser powder bed fusion (LPBF) tends to induce cracks, distortions, and overheating problems. In this work, to address these challenges, we explored and established a suitable strategy for producing large AlSi10Mg components. The platform temperatures to prevent cracks and distortions were firstly determined. Then, the in situ aging behavior was investigated for samples under various platform temperatures and holding times. Our results revealed that platform temperatures of 150°C and 200°C can effectively prevent cracks and minimize distortions. Besides, using 150°C, samples can reach peak hardness with a holding time less than 13 h. In comparison, those samples produced with a holding time longer than 13 h at 150°C and 200°C show obvious over-aging responses and thus lower hardness. However, such a hardness impoverishment can be recovered by using a T6 post-process heat-treatment. [ABSTRACT FROM AUTHOR]

Portioning-out and individuation are two important semantic properties for the characterization of countability. In Mandarin, nouns are not marked with count-mass syntax, and it is controversial whether individuation is encoded in classifiers or in nouns. In the present study, we investigates the interpretation of a minimal pair of non-interrogative wh -pronominal phrases, including duo-shao -N and duo-shao-ge -N. Due to the presence/absence of the individual classifier ge , these two wh -pronominal phrases differ in how they encode portioning-out and individuation. In two experiments, we used a Truth Value Judgment Task to examine the interpretation of these two wh -pronominal phrases by Mandarin-speaking adults and 4-to-6-year-old children. We found that both adults and children are sensitive to their interpretative differences with respect to the portioning-out and individuation properties. They assign either count or mass readings to the bare wh -pronominal phrase duo-shao -N depending on specific contexts, but only count readings to the classifier-bearing wh -pronominal phrase duo-shao-ge -N. Moreover, the portioning-out and individuation properties associated with the individual classifier ge emerge independently in the course of language development, with the portioning-out property taking precedence over the individuation property. Taken together, the present study provides new evidence for the view that the portioning-out and individuation properties in Mandarin are encoded in classifiers rather than in nouns, and these two semantic properties are two distinct components in our grammar. [ABSTRACT FROM AUTHOR]

In this work, the effects of nominal reductions during forging experiments on microstructures, tensile and fatigue properties of Ti-6Al-4V have been investigated. The microstructure of the starting material was a combination of equiaxed and lamellar α phases. With further deformation and annealing heat treatment, the volume fraction of globular primary α increased by about 20% as the nominal reduction increased from 10 to 50%. More notably, the ultimate tensile stress and yield stress were increased by approximately 50 MPa, and the ductility remained constant, with the nominal reduction from 10 up to 50%. Further detailed characterization revealed that the improvement in tensile and fatigue properties could be attributed to the reduction in the effective slip length, increase in the interface density, and realignment of the (0002) planes with the tensile axis. [ABSTRACT FROM AUTHOR]

Purpose: Limited research has attempted to reveal the different modes of the melt pool formation in additive manufacturing. This paper aims to study the mechanisms of surface roughness formation, especially on the aspect of melt pool formation which determine the surface profile and consequently significantly influence the surface roughness. Design/methodology/approach: In this study, the conditions under which different modes of melt pool formation (conduction mode and keyhole mode) occur for the case of as-fabricated Hastelloy X using direct metal laser solidification (DMLS) are derived and validated experimentally. Top surfaces of uni-directionally built samples under various processing conditions are cut, grinded, polished and etched to reveal their individual melt pool morphologies. Similarly, up-skin (slope angle < 90°) and down-skin (slope angle > 90°) melt pool morphologies are also investigated to compare the differences. Surface tension gradients and resultant Marangoni flow, which dominate the melt flow in the melt pool, is also calculated to help better evaluate the melt pool shape forming. Findings: Two types of melt pool formation modes are dominating in DMLS: conduction mode and keyhole mode. Melt pool formed by conduction mode generally has an aspect ratio of 1:2 (depth vs width) and is in elliptical shape. Appropriate selection of scanning laser power and speed are required to maintain a low characteristic length and width ratio to prevent ballings. Melt pool formed by keyhole mode has an aspect ratio of 1:1 or less. High-energy contour promotes formation of key-hole-shaped melt pool which fills the gaps between layers and smoothens the up-skin surface roughness. Low-energy contour scan is necessary for down-skin surface to form small melt pool profiles and achieve low Ra. Originality/value: This paper provides valuable insight into the origins of surface quality problem of DMLS, which is a very critical issue for upgrading the process for manufacturing real components. This paper helps promote the understanding of the attributes and capabilities of this rapidly evolving three-dimensional printing technology and allow appropriate control of processing parameters for successful fabrication of components with sound surface quality. [ABSTRACT FROM AUTHOR]

The chemical vapor infiltration (CVI) SiC/SiC composites are porous materials, and the porosity affects the molten salt infiltration and may affect the mechanical properties. Therefore, the internal microstructures of the 2D and 3D silicon carbide composites are studied by synchrotron radiation micro‐computed tomography (micro‐CT) technology. The cross‐sectional slice and 3D volume image of the composite are reconstructed, then the pores of the composites are visualized in three dimensions, and the porosity is quantitatively analyzed. The results indicate that most of small pores (micrometer) exist between filaments and larger pores (millimeter) occur between fiber bundles, and the internal pores of 2D and 3D composites are greatly influenced by the fabric structure. In contrast, the 3D braided composites have lower porosity, smaller pore distribution fluctuations, and more stable internal structure. [ABSTRACT FROM AUTHOR]

Using gas flow to reduce laser plume attenuation is critical in the process control of laser powder bed fusion (LPBF) of metal powders. First, this work investigated Hastelloy X (HX) samples built at different gas flow speeds. Higher porosity with lack of fusion defects was found in the samples built at lower gas flow speeds, which indicates a significant influence of laser plume attenuation. Then, particle pickup experiments were conducted to investigate the limit of further increasing the gas flow speed without disturbing the powder bed. Eight different powders of four alloys (Al, Ti, steel, and Ni) with mean sizes ranging from 25 µm to 118 µm were studied. A model was introduced to predict the pickup speeds of different powders. Lastly, a method based on porosity and particle pickup speed was proposed for the reference of setting the lower and upper limits of gas flow speed in LPBF. [ABSTRACT FROM AUTHOR]

The steady state heat flow meter is used as the test method. The intervals of thickness and temperature difference of the sample is 10 mm and 10 °C. The thermal conductivity of 15 mm to 100 mm white molded sheets and black molded sheets under the temperature difference of 10 °C to 40 °C was tested. The test results show that with the increase of the thickness of the sample, the thermal conductivity coefficient is inconsistent with the theory and shows a growing trend. When the sample is too thin or too thick, the relative deviation of the test results is large, exceeding the accuracy range of the equipment test ±3%. The temperature difference has little effect on the test results of the thermal conductivity. The relative deviation of the thermal conductivity test of both the white and black polystyrene plates is less than ±0.5%. [ABSTRACT FROM AUTHOR]

The correct differentiation of oligodendrocyte precursor cells (OPCs) is essential for the myelination and remyelination processes in the central nervous system. Determining the regulatory mechanism is fundamental to the treatment of demyelinating diseases. By analyzing the RNA sequencing data of different neural cells, we found that cyclin-dependent kinase 18 (CDK18) is exclusively expressed in oligodendrocytes. In vivo studies showed that the expression level of CDK18 gradually increased along with myelin formation during development and in the remyelination phase in a lysophosphatidylcholine-induced demyelination model, and was distinctively highly expressed in oligodendrocytes. In vitro overexpression and interference experiments revealed that CDK18 directly promotes the differentiation of OPCs, without affecting their proliferation or apoptosis. Mechanistically, CDK18 activated the RAS/mitogen-activated protein kinase kinase 1/extracellular signal-regulated kinase pathway, thus promoting OPC differentiation. The results of the present study suggest that CDK18 is a promising cell-type specific target to treat demyelinating disease. [ABSTRACT FROM AUTHOR]

Purpose: Selective laser melting (SLM) process is an additive manufacturing method that uses computer-aided design to fabricate complex components layer-by-layer. Surface roughness is one of the primary drawbacks of SLM process; hence, the purpose of this paper is to present a parametric study and optimisation of fundamental parameters, including scan power, speed, inclined angle and layer thickness on surface roughness during selective laser melting of Hastelloy X. Design/methodology/approach: Parametric significance on surface finish was analysed using analysis of variance and response surface methodology. General agreement between predicted and measured values was achieved. Surface characteristics of both up-skin and down-skin with various angles were covered within the investigated range. Findings: Both experimental and statistical analysis showed that surface roughness of up-skin was primarily influenced by scan power, inclined angle and layer thickness while down-skin was more affected by the former two factors. Melt pool shape and staircase size were found to determine the up-skin surface, whereas attached particles were responsible for down-skin surface roughness. Originality/value: As per our understanding, this manuscript provides valuable insight into the surface quality problem of SLM, which is a very critical issue for up-grading the process for manufacturing real components. This manuscript helps promote improved knowledge and understanding of the attributes and capabilities of this rapidly evolving 3D printing technology. Moreover, it establishes usable processing window and helps obtain optimal conditions, thus offering useful information to professionals working in this field. By combining experiments with statistical analysis, both practice and theory relevant to SLM process are further developed. [ABSTRACT FROM AUTHOR]

Thermal conductivity is an important index for evaluation of the thermal insulation performance of thermal insulation materials. The thermal conductivity of extruded polystyrene (XPS) boards with different surface structures was investigated. The results indicated that the thermal conductivity of XPS boards with a grooved surface was slightly influenced by their surface structure. There is a fair structural influence on the thermal conductivity of XPS boards with the one side removed from the skin. However, the thermal conductivity of the XPS board with the double-sides removed from the skin was reduced significantly. [ABSTRACT FROM AUTHOR]

The differentiation and maturation of oligodendrocyte precursor cells (OPCs) is essential for myelination and remyelination in the CNS. The failure of OPCs to achieve terminal differentiation in demyelinating lesions often results in unsuccessful remyelination in a variety of human demyelinating diseases. However, the molecular mechanisms controlling OPC differentiation under pathological conditions remain largely unknown. Myt1L (myelin transcription factor 1-like), mainly expressed in neurons, has been associated with intellectual disability, schizophrenia, and depression. In the present study, we found that Myt1L was expressed in oligodendrocyte lineage cells during myelination and remyelination. The expression level of Myt1L in neuron/glia antigen 2-positive (NG2+) OPCs was significantly higher than that in mature CC1+ oligodendrocytes. In primary cultured OPCs, overexpression of Myt1L promoted, while knockdown inhibited OPC differentiation. Moreover, Myt1L was potently involved in promoting remyelination after lysolecithin-induced demyelination in vivo. ChIP assays showed that Myt1L bound to the promoter of Olig1 and transcriptionally regulated Olig1 expression. Taken together, our findings demonstrate that Myt1L is an essential regulator of OPC differentiation, thereby supporting Myt1L as a potential therapeutic target for demyelinating diseases. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is a classical inflammatory demyelinating disease of the central nervous system (CNS). Microglia are the main resident immune cells in the CNS and are closely associated with the pathogenesis of MS. In the present study, we found that miR-30a was highly expressed in jellyfish-like microglia in chronic active lesions of MS patients, as well as in the microglia of mice with experimental autoimmune encephalomyelitis (EAE) at the chronic phase. In vitro, the conditioned supernatant of mouse microglia overexpressing miR-30a promoted the apoptosis of oligodendrocyte precursor cells (OPCs), and inhibited OPC differentiation. In vivo, overexpressing miR-30a in transplanted microglia exacerbated the progression of EAE. Overexpression and knock-down experiments in primary cultured mouse microglia showed that miR-30a increased the expression of IL-1β and iNOS, which are pro-inflammatory, while inhibiting the expression of Ym-1 and CD206. Mechanistically, miR-30a inhibited the expression of Ppargc1b, which is the co-activator of peroxisome proliferator-activated receptor gamma, resulting in pro-inflammatory effects. Our work shows that miR-30a is an important regulator of the inflammatory response in microglia, and may be a promising therapeutic target for inflammatory diseases like MS in the CNS. [ABSTRACT FROM AUTHOR]

The regulation of inflammation is pivotal for preventing the development or reoccurrence of multiple sclerosis ( MS). A biased ratio of high-M1 versus low-M2 polarized microglia is a major pathological feature of MS. Here, using microarray screening, we identify the long noncoding RNA (lnc RNA) GAS5 as an epigenetic regulator of microglial polarization. Gain- and loss-of-function studies reveal that GAS5 suppresses microglial M2 polarization. Interference with GAS5 in transplanted microglia attenuates the progression of experimental autoimmune encephalomyelitis ( EAE) and promotes remyelination in a lysolecithin-induced demyelination model. In agreement, higher levels of GAS5 are found in amoeboid-shaped microglia in MS patients. Further, functional studies demonstrate that GAS5 suppresses transcription of TRF4, a key factor controlling M2 macrophage polarization, by recruiting the polycomb repressive complex 2 ( PRC2), thereby inhibiting M2 polarization. Thus, GAS5 may be a promising target for the treatment of demyelinating diseases. [ABSTRACT FROM AUTHOR]

Heat-treated Ti-6Al-4V forged bar with colony microstructure was machined into double-cone-shaped samples for a series of isothermal uniaxial compression test at 1223 K (950 °C) with varying constant crosshead speeds of 12.5, 1.25, and 0.125 mms to a height reduction of 70 pct. Another set of samples deformed under the same conditions were heat treated at 1173 K (900 °C) for an hour followed by water quench. Finite element modeling was used to provide the strains, strain rates, and temperature profiles of the hot compression samples, and the microstructure and texture evolution was examined at four positions on each sample, representative of different strain ranges. Lamellae fragmentation and kinking are the dominant microstructural features at lower strain range up to a maximum of 2.0, whereas globularization dominates at strains above 2.0 for the as-deformed samples. The globularization fraction generally increases with strain, or by post-deformation heat treatment, but fluctuates at lower strain. The grain size of the globular α is almost constant with strain and maximizes for samples with the lowest crosshead speed due to the longer deformation time. The globular α grain also coarsens because of post-deformation heat treatment, with its size increasing with strain level. With respect to texture evolution, a basal transverse ring and another component 30 deg from ND is determined for samples deformed at 12.5 mms, which is consistent with the temperature increase to close to β-transus from simulation results. The texture type remains unchanged with its intensity increased and spreads with increasing strain. [ABSTRACT FROM AUTHOR]

Aim To investigate the association between red cell distribution width ( RDW) and the severity of hepatitis B virus ( HBV)-related liver diseases. Methods Sixty-nine patients with chronic hepatitis B ( CHB) and 61 patients with HBV-related liver cirrhosis were enrolled in the present study. Forty-one healthy individuals were included as controls. Hematological parameters, hepatitis B e-antigen ( HBe Ag) status, HBV DNA levels and liver biochemistry were analyzed. Child- Pugh scores and Model for End- Stage Liver Disease ( MELD) scores of the patients with HBV-related liver cirrhosis were calculated. Results The RDW was significantly higher in patients with HBV-related liver cirrhosis as compared with CHB patients and healthy controls. RDW was slightly higher in CHB patients as compared with healthy controls. An increasing correlation of RDW with Child- Pugh grades was found. RDW was positively correlated with Child- Pugh scores and MELD scores. In patients with HBV-related liver cirrhosis, RDW was also positively correlated with total bilirubin and negatively correlated with hemoglobin and serum albumin concentration. However, no significant difference was found between HBe Ag positive and negative patients and no significant correlation between RDW and HBV DNA levels was found. Conclusion The RDW was elevated in CHB patients and patients with HBV-related liver cirrhosis and was positively correlated with the severity of HBV-related liver cirrhosis. RDW is a potential index to assess the severity of HBV-related liver diseases. [ABSTRACT FROM AUTHOR]

The dwell effects of Ti624 x ( x = 2 to 6) alloys, including dwell fatigue life debit, fracture mode and strain accumulation, were characterized and compared. With increasing Mo content, the dwell fatigue life debit decreases quickly, and dwell fatigue fracture exhibits a transition from subsurface to surface initiation. Accompanying these changes, the accumulated strain decreases, and the pattern of secondary cracks loses morphological features typical of dwell cracks. These variations in the fatigue behavior of Ti624 x were attributed on the fundamental level to the dual effects of Mo: It decreases the β transus of titanium and, as a slow diffuser, reduces the rate of phase transformation from β to α. A higher Mo content encourages nucleation of multiple variants of α laths and promotes the transition from aligned colonies to basketweave microstructure during cooling after β forging. As a result both the grain size and microtexture intensity of α grains in the two-phase processed and heat treated microstructure are reduced. Smaller grain size of the alloys with higher Mo content produces smaller slip band spacing and reduces accumulated strain during dwell fatigue, thus reducing propensity for crack initiation. Microtexture was shown to be the direct cause of dwell sensitivity, and their relationship was described with the aid of a two-region redistribution model based on a previous two-element redistribution model proposed by Bache. [ABSTRACT FROM AUTHOR]

In addition to serving as question markers with interrogative force,wh-words such asshenme‘what’ in Mandarin Chinese have a noninterrogative meaning. For the noninterrogative meaning, these words have been typically analyzed as negative polarity items, i.e., aswh-pronouns that are similar in meaning to the English NPIanyand to its Mandarin counterpartrenhe. This accounts for the None reading that is generated in negative statements withwh-words. However, negative sentences with thewh-wordshenme‘what’ can also be assigned another reading, in certain circumstances. We refer to this as the Insignificance (not much) reading. This reading is not possible for sentences with the NPIrenhe. The None reading is the default interpretation for negative sentences with eitherrenheorshenmebecause the Insignificance reading of the negatedshenmesentences requires contextual support. Like English “not much,” the Insignificance reading of negatedshenmesentences in Mandarin makes a sentence true in a broader range of circumstances than the corresponding sentence with the NPIrenhe. Both the fact that the Insignificance reading requires contextual support and considerations of language learnability in the absence of negative evidence lead us to expect the Insignificance reading to emerge later than the None reading in the course of language development. An experimental study of Mandarin-speaking children of different ages supported this expectation. The youngest group of children only assigned the None reading to negative sentences withshenmeas well as to sentences withrenhe. However, older children and adults accessed the Insignificance reading. [ABSTRACT FROM AUTHOR]

The present study investigated Mandarin-speaking children's acquisition of the polarity sensitive item renhe ‘any’ in Mandarin Chinese. Like its English counterpart any, renhe can be used as a negative polarity item (NPI), or as a free choice (FC) item, and both the distribution and interpretation of renhe are governed by the same syntactic and semantic constraints as English any. Using a Truth Value Judgment Task, the present study tested five-year-old Mandarin-speaking children's comprehension of FC renhe in sentences containing the modal word neng ‘can’, and tested children's comprehension of NPI renhe in sentences containing the temporal conjunction zai…zhiqian ‘before’. Most children demonstrated knowledge of the interpretation of both FC renhe and NPI renhe despite a paucity of relevant adult input. Like adults, however, Mandarin-speaking children do not use renhe frequently in ordinary conversation, due to the availability of alternative colloquial expressions (wh-pronouns) that also convey children's intended meanings. [ABSTRACT FROM AUTHOR]

The present study investigated Mandarin-speaking children's acquisition of the polarity sensitive item renhe ‘any’ in Mandarin Chinese. Like its English counterpart any, renhe can be used as a negative polarity item (NPI), or as a free choice (FC) item, and both the distribution and interpretation of renhe are governed by the same syntactic and semantic constraints as English any. Using a Truth Value Judgment Task, the present study tested five-year-old Mandarin-speaking children's comprehension of FC renhe in sentences containing the modal word neng ‘can’, and tested children's comprehension of NPI renhe in sentences containing the temporal conjunction zai…zhiqian ‘before’. Most children demonstrated knowledge of the interpretation of both FC renhe and NPI renhe despite a paucity of relevant adult input. Like adults, however, Mandarin-speaking children do not use renhe frequently in ordinary conversation, due to the availability of alternative colloquial expressions (wh-pronouns) that also convey children's intended meanings. [ABSTRACT FROM PUBLISHER]

Anax parthenope (Odonata: Aeshnidae) is a big dragonfly which can be seen patrolling around ponds, lakes and other still water. In this study, we sequenced and analyzed the complete mitochondrial genome (mitogenome) of A. parthenope. This mitogenome was 15,366 bp long and encoded 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs) and two ribosomal RNA unit genes (rRNAs). The nucleotide composition of the mitogenome was biased toward A and T, with 74.8% of A + T content (A 40.1%, T 34.7%, C 14.0%, G 11.2%). Gene order was conserved and identical to most other previously sequenced Aeshnidae dragonflies. Most PCGs of A. parthenope have the conventional start codons ATN (six ATG, three ATT, and two ATC), with the exception of cox1 and nad1 (TTG). Except for three genes (cox1, cox2, and nad5) end with the incomplete stop codon T––, all other PCGs terminated with the stop codon TAA. Phylogenetic analysis showed that A. parthenope is sister to Anax imperator with high support value. All 15 Anisoptera species constituted a major clade with well support, and Aeshnidae had a close relationship with Gomphidae and Libellulidae. [ABSTRACT FROM AUTHOR]

Pseudothemis zonata is a commonly seen dragonfly with a big yellow or white ringlike spot on the third and fourth segments of its abdomen. In this study, we sequenced and analyzed the complete mitochondrial genome (mitogenome) of P. zonata. This mitogenome was 15,434 bp long and encoded 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), and 2 ribosomal RNA unit genes (rRNAs). Gene order was conserved and identical to most other previously sequenced Libellulidae dragonflies. The whole mitogenome exhibited heavy AT nucleotide bias (74.6%). Most PCGs of P. zonata have the conventional start codons ATN (six ATG, three ATT, and two ATC), with the exception of cox1 and nad1 (TTG). Except for four genes (cox1, cox2, cox3, and nad5) end with the incomplete stop codon T−, all other PCGs terminated with the stop codon TAA or TAG. Phylogenetic analysis showed that P. zonata got together with Brachythemis contaminata with high support value, and the relationships ((Brachythemis + Psolodesmus) + ((Hydrobasileus + Trigomphus) + (Orthetrum + Acisoma))) were supported in Libellulidae. [ABSTRACT FROM AUTHOR]

Diarrhetic shellfish poisoning (DSP) is a gastrointestinal illness with symptoms such as diarrhea, nausea, vomiting, headache, chills and moderate to severe abdominal pain. DSP has been recognized as a worldwide public health problem, causing great concern to the shellfish industry. Accumulation of DSP in shellfish is an unpredictable phenomenon that necessitates the implementation of a widespread collection and thorough monitoring program for mollusk toxicity. Therefore, development of accurate analytical protocols for the rapid determination of toxicity levels would be necessary. In this study we investigated cytoskeletal changes induced by okadaic acid in HL-7702 Liver Cells and developed a new cytotoxicity assay for detection and quantitation of DSP. This assay is based on fluorometric of F-actin depolymerization induced by okadaic acid (OA) compounds in HL-7702 liver cell line. The measurable range of OA was 2.5 ∼ 40 nmol/L. The detection limit of the F-actin assay for OA was 2.01 μg/100 g muscles in shellfish extracts. The performance of this assay has been evaluated by comparative analysis of shellfish samples by the fluorescent assay, mouse bioassay, and ELISA assay. Comparison of the results by all three methods revealed excellent consistency, the results of fluorescent assay were in significant correlation with ELISA assay ( R2 = 0.830). Examination of F-actin assay is very convenient, rapid, and sensitive, which can be used to quantify the amount of OA in shellfish samples. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013. [ABSTRACT FROM AUTHOR]

Keywords: Passion fruit; Begomovirus; Euphorbia leaf curl virus; papaya leaf curl Guangdong virus EN Passion fruit Begomovirus Euphorbia leaf curl virus papaya leaf curl Guangdong virus 1367 1367 1 11/29/21 20211101 NES 211101 Supplementary Information The online version contains supplementary material available at https://doi.org/10.1007/s42161-021-00932-z. Passion fruit, Begomovirus, Euphorbia leaf curl virus, papaya leaf curl Guangdong virus Euphorbia leaf curl virus (EuLCV) and papaya leaf curl Guangdong virus (PaLCuGDV), which can cause obvious symptoms on passion fruit, were first reported in Asia (Cheng et al. [1], Kil et al. [3]). [Extracted from the article]

The black citrus aphid Aphis aurantii is a major pest of citrus and tea plants. In this study, we determined the complete mitochondrial genome (mitogenome) of A. aurantii. The mitogenome was 15,469 bp in length, consisting of 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and a non-coding control region. Gene order of A. aurantii was highly conserved and identical to most other previously sequenced Aphididae. Initiation codons ATT, ATA, and ATG were identified in eight, three, and two PCGs, respectively, while stop codon TAA was found in 11 genes except for 2 genes (cox1 and nad4) which use incomplete stop codon T–. Phylogenetic analysis showed the topology (Pemphigidae + (Hormaphididae + (Greenideidae + Aphididae))) within Aphidoidea, and A. aurantii was more closely related to Aphis craccivora than to Aphis gossypii. [ABSTRACT FROM AUTHOR]