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Freezing of water under nanoconfinement exhibits physical peculiarities with respect to the bulk water. However, experimental observations are extremely challenging at this scale, which limits our understanding of the effect of confinement on water properties upon freezing. In this study, we use molecular dynamic simulations to investigate how confinement affects the kinetics of growth of ice and the thermodynamic equilibrium of ice-liquid coexistence. TIP4P/Ice water model and CSH-FF model were applied to simulate ice crystallization in a confined cement system at temperatures down to 220 K. We adapted an interface detection algorithm and reparameterized the CHILL/CHILL+ algorithm to capture ice growth. The confinement leads to a shift of the maximum growth rate of ice to a higher temperature than for bulk water. Both the confinement and surface impurities contribute to slowing down the ice growth. For the ice-liquid coexistence at equilibrium, we derive a formulation of Thomson's equation adapted to statistical physics quantities accessible by molecular simulation, and we show that this adapted equation predicts accurately the melting line of bulk and confined ice Ih as a function of pressure. The confinement decreases systematically the melting temperature of ice of about 5 K compared with bulk ice Ih. A premelted water film about 1 nm thick is observed between the solid wall and ice, and its thickness is found to decrease continuously as temperature is lowered. We note that the surface impurities are key to the formation of the premelted water nanofilm when the temperature is lower than 250 K. [ABSTRACT FROM AUTHOR]

To promote the application of automated vehicles in large airports, in this study, we present an integrated optimization method for scheduling Unmanned follow-me cars. The scheduling process is divided into three phases: Dispatch, Guidance, and Recycle. For the Dispatch phase, we establish a vehicle assignment model, to allocate the vehicle resource equitably. For the Guidance phase, we offer an quantitative way, to measure the spacing between Unmanned follow-me car and aircraft. To optimize the efficiency of airport operation in the three phases and ensure safety, the collaborative planning model, and the conflict prediction model are established. An improved grey wolf optimization algorithm is adopted to enhance the convergence speed and generalization performance. A case study at Ezhou Huahu Airport in China demonstrates the effectiveness of the methods. The results show that the model of collaborative planning can make the balance of path selection, Unmanned follow-me car's working time, and departure sequence. The convergence speed of the improved algorithm has been increased by 18.75%. The inequity index of vehicle assignment is only 0.015731, and the spatiotemporal distribution of conflicts is influenced by the airport's surface layout. [ABSTRACT FROM AUTHOR]

This study aims to unveil the spatiotemporal evolution of congestion within terminal airspace, offering an in-depth analysis of congestion concerns to effectively utilize airspace resources and devise targeted control strategies, thereby enhancing airspace operation safety and efficiency. Initially, converting segment flow rates into equivalent speeds serves as a quantitative benchmark for operational status. Subsequently, an enhanced version of the ST-Moran's I index model, specifically tailored to terminal airspace, is developed by incorporating improvements across spatial weight matrices, standard state parameters, and temporal dimensions. Validating this model with actual operational data from Chengdu's terminal airspace, the research demonstrates significant advancements. Compared to conventional models, the proposed model enhances recognition rates for congestion in spatial and temporal dimensions by 62.5% and 43.61%, respectively. Congestion within terminal airspace predominantly occurs at the intersection of departure-climb and approach-departure segments, exhibiting evident spatiotemporal migration behavior. The proposed model accurately delineates the spatiotemporal characteristics of segment congestion, offering support for tailored congestion management strategies. [ABSTRACT FROM AUTHOR]

• Combined therapy with DHA and cisplatin exerts synergistic anti-NSCLC activity through activating ROS-mediated ER stress, JNK and p38 MAPK signaling pathways both in vitro and vivo. • PTGS1 is identified as a potential novel target of DHA. Knockdown of PTGS1 enhanced DHA-induced cell death in NSCLC cells through stimulating ROS-mediated ER stress, JNK and p38 MAPK signaling pathways. Dihydroartemisinin (DHA) exerts an anti-tumor effect in multiple cancers, however, the molecular mechanism of DHA and whether DHA facilitates the anti-tumor efficacy of cisplatin in non-small cell lung cancer (NSCLC) are unclear. Here, we found that DHA potentiated the anti-tumor effects of cisplatin in NSCLC cells by stimulating reactive oxygen species (ROS)-mediated endoplasmic reticulum (ER) stress, C-Jun-amino-terminal kinase (JNK) and p38 MAPK signaling pathways both in vitro and in vivo. Of note, we demonstrated for the first time that DHA inhibits prostaglandin G/H synthase 1 (PTGS1) expression, resulting in enhanced ROS production. Importantly, silencing PTGS1 sensitized DHA-induced cell death by increasing ROS production and activating ER-stress, JNK and p38 MAPK signaling pathways. In summary, our findings provided new experimental basis and therapeutic prospect for the combined therapy with DHA and cisplatin in some NSCLC patients. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper aims to reveal the mechanical evolution and potential mechanism of Ultra-high Performance Concrete (UHPC) exposed to a complex temperature-variation environment typical of Liquefied Natural Gas storage tank. Herein, the effect of steel fiber geometries (straight and hooked-end) on flexural failure of UHPCs in the range of −170 °C ∼ 200 °C was studied, and dynamic fracture evolution during the loading process was tracked using acoustic emission (AE) test. Results indicated that the flexural strength of concrete specimen enhanced at −170 °C but diminished at 200 °C in the first cycle. For multiple cycles, its improved strength subsisted until the third cycle, after which gradually decreased. Moreover, the hooked-end fiber generally had superior strengthening and toughening effects than straight fiber, except for cryogenic temperature and third cycles tests. At cryogenic temperature, the freezing of pore moisture inside specimen enhanced the matrix strength and the interfacial bonding between the matrix and fibers. At elevated temperature, the thawing, diffusion and evaporation of moisture in concrete could induce matrix dehydration and weaken the bonding effect between interfaces. In varying exposure environments, the moisture migration would also undergo secondary hydration reactions with unreacted cement particles. Finally, using AE parameters to effectively record damage progression in UHPCs exposed to extreme temperatures was also highlighted. [ABSTRACT FROM AUTHOR]

Powder coating is a widely utilized and environmentally friendly coating method. It is well known that the particle size distribution (PSD) of a powder coating significantly impacts its properties and film performance. However, current powder coatings generally have wide PSDs, primarily due to the suboptimal classifying function of the grinding system—air classifying mill (ACM). In this study, self-designed ACM classifiers were built and tested to improve the classifying function and attain narrow-PSD powder coatings. These self-designed classifiers contributed to powder coatings with narrower PSDs (span ≤ 1.4), which have significantly decreased D 90 and increased D 10 compared to the ones prepared by the control classifier (span > 1.6). Furthermore, these narrowed-PSD powder coatings demonstrated improved flowability, and the coating films displayed superior gloss and smoothness. Overall, this facile and straightforward modification to the ACM classifier has effectively enhanced the classifying function of ACM, contributing to a narrowed PSD and improved quality of powder coatings. [Display omitted] • Serrated-edge classifiers of ACM yielded powder coatings with narrower PSD. • Narrower PSDs enhanced flowability, film smoothness, and gloss of powder coatings. • Serrated-edge's enhanced classifying function led to higher production yield. • Novel ACM classifier design has potential for versatile powder process industries. [ABSTRACT FROM AUTHOR]

Herein, a hierarchical cementitious calcium silicate hydrate (C-S-H) superstructure with high Young's modulus, super-low porosity, and low mass density is reported. It has a very high Young's modulus at 47.5 GPa, three times higher than our reference synthetic C-S-H. Its specific surface area is merely 0.4509 m2/g, two orders of magnitude smaller than our reference synthetic C-S-H and the most common construction materials. In addition, the skeletal density of this composite is 1.96 g/cm3, much lower than C-S-H and hardened cement paste. In a density-Young's modulus diagram, this composite is located at the intersection of metals, ceramics, and polymers, approaching the carbon fiber region, implying lightweight and stiff characteristics. The cryogenic stability is also evaluated. It shows a satisfying applicability potential for cryogenic engineering with stable pore structure and nanoscopic mechanical properties. We confirm that the assembly of hierarchical C-S-H superstructure requires both hydrophilic amide and anionic carboxylic groups. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the third most common cancer and leading cause of cancer related deaths worldwide. Despite recent advancements in surgical and molecular targeted therapies that improved the therapeutic efficacy in CRC, the 5 years survival rate of CRC patients still remains frustratingly poor. Accumulated evidences indicate that microRNAs (miRNAs) play a crucial role in the progression and metastasis of CRC. Dysregulated miRNAs are closely associated with cancerous phenotypes (e.g. enhanced proliferative and invasive ability, evasion of apoptosis, cell cycle aberration, and promotion of angiogenesis) by regulating their target genes. In this review, we provide an updated overview of tumor suppressive and oncogenic miRNAs, circulatory miRNAs, and the possible causes of dysregulated miRNAs in CRC. In addition, we discuss the important functions of miRNAs in drug resistance of CRC. [ABSTRACT FROM AUTHOR]

The COVID-19 global pandemic hit the aviation industry hard since the end of 2019. It has had an immediate, dramatic impact on airport traffic and revenue. Airports are the important nodes in the aviation system network, and the failure of a single airport can often affect the surrounding airports. The purpose of our analysis is to show how is the resilience and recovery of airports in the global public health crisis. Much research on resilience can be found in air transportation networks facing natural hazards or extreme weather, which focus on the robustness of the airport network. These methods are not suitable for the global public health event. Therefore, based on the collection of existing data, we combined with existing resilience measurement methods to analyze the resilience and recovery of airports during the global public health crisis. The resilience metrics results reflect the recovery of airports very well under different strategies. Here, we analyze airport network resilience by considering the performance-based methods. We integrate some metrics such as aircraft movements, passenger throughput, and freight throughput in the resilience metrics model, comparing the resilience evaluation under different preventive and control strategies, which can reflect the airport's recovery speed during the COVID-19 pandemic. Our analysis indicates that the aviation system network deteriorates soon after the COVID-19 outbreak, but the recovery level of the aviation industry depends on what measures are taken to prevent and control the COVID-19 epidemic. In particular, the recovery of the aviation system network in Europe takes longer than in China, due to different prevention and control strategies for COVID-19. The study proves that the emergency response ability of the country for the public health crisis has a significant positive impact on speeding up the recovery of the aviation system. [ABSTRACT FROM AUTHOR]

The premelted films between cement and ice observed at freezing temperatures play a role in the freeze-thaw damage of cement-based materials, as they play a role in cryo-suction. However, their properties are poorly understood. In this work, we unveil the dynamics and local structure of the premelted film using molecular simulations. Combining those results with a thermodynamic analytical derivation, we obtain a characteristic time of the cryo-suction process, which depends on temperature, the transport properties and thickness of the premelted film, and the pore geometry. Our calculations show that, down to about 230 K, cryo-suction occurs relatively fast at the pore scale and the hypothesis of local thermodynamic equilibrium used in most poromechanical models of freezing of cement-based materials is reasonable. A fragile-to-strong transition of water in the premelted films is witnessed at about 230 K. Below this temperature, the significant deceleration of water dynamics makes the cryo-suction significantly slower. [ABSTRACT FROM AUTHOR]

This paper investigates the scaling of the nanoscopic elastic and tensile failure properties of calcium-silicate-hydrate (C-S-H). We report a Zhurkov-like scaling behavior for disordered C-S-H of various compositions at cryogenic temperatures, using molecular dynamics simulations. To this end, we first propose a revised molecular construction route to generate C-S-H atomic configurations with varying compositions. Then, we investigate how the tensile behavior evolves with temperature, system size, and strain rate. Our simulation results show that tensile strength, Young's modulus, fracture energy, and fracture-process zone (FPZ) length, all follow a Zhurkov-like scaling law providing a general temperature-size-time equivalence. Such scaling laws make it possible to extrapolate molecular simulation results to larger length and/or time scales. Detailed analysis shows that the typical FPZ length of C-S-H is about 150 Å, and the maximum reduction of activation energy barriers for tensile failure is 0.497 and 0.446 eV for Ca/Si of 1.7 and 1.1, respectively. [ABSTRACT FROM AUTHOR]

Herein, we report a cryogenic attack study on C-A-S-H with bulk Ca/(Al + Si) = 0.84–1.75, Al/(Al + Si) = 0.1, 0.2. The C-A-S-H nanostructure variations are quantitively analyzed using thermogravimetric analysis, single-pulse 29Si, and 27Al MAS NMR. Observing the conversion of tetrahedral aluminates to octahedral ones in the absence of depolymerization, we confirm the presence of bridging octahedral aluminates in C-A-S-H chains. The consistency between the slight polymerization and the decrease of pentahedral aluminate fraction in low-Al C-A-S-H reveals the existence of interlayer pentahedral aluminate. The depolymerization in high-Al C-A-S-H is accompanied by conversion of pentahedral aluminate to octahedral aluminate, which confirms the presence of bridging pentahedral and interlayer octahedral aluminates. We further identify the complexes for each structural unit. Then, a DNA-code rule is proposed to describe C-A-S-H atomistic structure considering both bridging and interlayer aluminates. Finally, we propose a general structural-chemical formula for C-A-S-H. [ABSTRACT FROM AUTHOR]

Different weakening buffer operators in a time-series model analysis usually result in different model sensitivities, which sometimes affect the effectiveness of relevant operator-based methods. In this paper, the stability of two classic fractional-order weakening buffer operator-based series models is studied; then, a new data preprocessing method based on a novel fractional-order bidirectional weakening buffer operator is provided, whose effect in improving the model's stability is tested and utilized in prediction problems. Practical examples are employed to demonstrate the efficiency of the proposed method in improving the model's stability in noise scenarios. The comparison indicates that the proposed method overcomes the disadvantage of many weakening buffer operators in the subjectively biased weighting of the new or old information in forecasting. These expand the application of the proposed method in time series analysis. [ABSTRACT FROM AUTHOR]

Herein, the intrinsic nanomechanical transition of calcium-(alumino)silicate-hydrate (C-(A)-S-H) upon ultra-low temperature attack and the potential role of aluminum incorporation as a bottom-up enhancement strategy are investigated. C-(A)-S-H is experimentally synthesized using an efficient hydrothermal reaction, and statistical AFM-based indentation, nitrogen sorption, SEM, and AFM observations are carried out. Note that the C-A-S-H is clarified in more ordered topographic features than Al-free C-S-H. The nanomechanical measurements reveal that the ultra-low temperature attack provoked the nano-brittleness of C-(A)-S-H. Nevertheless, the nanomechanical degradation is seen for Al-free C-S-H only. This brittle transition is attributed to the rise of the high-density phase fraction, though the elastic moduli of its decomposed phases decrease. In comparison, the brittle transition of C-A-S-H is ascribed to the increasing elastic moduli of its decomposed phases. It is further proved that such transitions are irrelevant to the packing nature of gel grains but involved with the variation of their intrinsic nanomechanical natures since the gel pore systems remain stable under the ultra-low temperature attack. These results advance fundamental knowledge toward developing cryogenic stable cement-based materials from a bottom-up insight. [ABSTRACT FROM AUTHOR]

Low-carbon calcium (alumino)silicate hydrate (C-(A)-S-H) based composites (e.g., blended cement-based materials and alkali-activated materials) have broad application potential in ultra-low-temperature engineering areas. This study devotes to reveal the structural stability of C-(A)-S-H under ultra-low temperature attack (−170 °C) and evaluating the role of aluminum as a bottom-up enhancement strategy for C–S–H. The atomic structure, interlayer structure, internal basic building block structure, pore network, and micro-morphology were experimentally studied using 29Si MAS NMR, XRD, helium pycnometry, nitrogen adsorption, and SEM. These results indicate that an ultra-low temperature attack can deteriorate C-(A)-S-H structure, even though without the presence of bulk water, whereas the incorporation of aluminum positively stabilizes C-(A)-S-H structure. The silicate chains of Al-free C–S–H are ruptured with more defective vacant sites, which consequently initiates a decline in its d 002 interlayer space and the volume collapse of basic building blocks, further resulting in the formation of microcracks. In contrast, aluminosilicate chains of C-A-S-H are more stable and even polymerized with longer chain length, stabilizing the micro/mesostructure. An upscaling degradation route from the atomic scale to mesoscale was proposed, providing a multiscale view to understand the degradation of concrete composites upon ultra-low temperature attack. We also confirm that incorporating aluminum in the silicate chains is an effective bottom-up strategy to enhance the cryogenic stability of C-(A)-S-H. [ABSTRACT FROM AUTHOR]

• The cryogenic attacks led to an increase in the adsorption energy of the first adsorbed layer on C-S-H. • The mesopore structure C-S-H with a higher Ca/Si ratio is better preserved under the impacts of the harshly cryogenic attack. • The ultramicropores and small supermicropores are more sensitive to the cryogenic attack than other larger micropores. • The harshly cryogenic attack has resulted in higher complexity and irregularity of mesopores and macropores of C-S-H. This study carried out a comprehensive nitrogen adsorption evaluation on the cryogenic attack impacts on the micropores and mesopores of calcium-silicate-hydrate (C-S-H). Pore volume and pore size distribution were analyzed by using Barrett-Joyner-Halenda (BJH), non-local density function theory (NLDFT), Dubinin-Radushkevich (DR), and Horvath-Kawazoe (H-K) methods. Surface fractal dimensions were analyzed by Frenkel-Halsey-Hill (FHH) model. The tortuosity factors were estimated using the corrugated pore structure model (CPSM) simulation. Results show that the cryogenic attack may chemically transform C-S-H surface, leading to a higher attraction to the adsorbates. The mesopores of C-S-H with a high Ca/Si ratio were better preserved. Furthermore, the ultramicropores and small supermicropores are more sensitive to the cryogenic attack than those larger micropores. In addition, it is found that the cryogenic attack has a significant influence in increasing the complexity and irregularity of the C-S-H mesopore structure. The CPSM simulation results provide additional evidence for the microcrack formation. [ABSTRACT FROM AUTHOR]

Abstract: A cDNA encoding heat shock protein 70 of Trichinella spiralis (Ts-Hsp70) was identified by immunoscreening the adult T. spiralis cDNA library with rabbit antisera against T. spiralis adult extracts. The open reading frame of Ts-Hsp70 cDNA encoded a 623-amino acid peptide with a predicted molecular weight of 68.7kDa, which shares a high degree of sequence conservation with HSP70s from other parasites. Recombinant Ts-Hsp70 was expressed in Escherichia coli and purified with nickel column chromatography. Western blot analysis showed that recombinant Ts-Hsp70 could be recognized not only by trichinellosis patient sera, but also by T. spiralis-infected sera from rabbits, swine, and mice. Mice vaccinated with recombinant Ts-Hsp70 formulated with Freund''s adjuvant exhibited strong humoral immune responses indicated by high titer of IgG antibody and significant muscle larval reduction (37%) after being challenged with T. spiralis larvae. The present results indicate that Ts-Hsp70 is a possible candidate vaccine against T. spiralis infection. [Copyright &y& Elsevier]

• Analysis the parameters adjustment range of the traditional method. • A dual parameters method was proposed to expand the range. • The best parameters selection is obtained by particle swarm optimization. • Our method has better balance between accuracy and diversity. With the unprecedented development in the internet technology, the information overload issues have become more and more complex, resulting in users being unable to obtain the target information accurately and effectively in selecting the required information from a large pool of surfed data. In view of this a recommendation system can be used to predict the user's selection probability for different potential objects as an important tool, which can help to solve the information overload issues. So far, many personalized recommendation algorithms based on bipartite graphS have been proposed, most of which are based on the similarity degree among users or items, such as collaborative filtering (CF), mass diffusion (MD) and heat conduction (HC). Among many recommendation algorithms, the performances of algorithms are varied. MD algorithm has high recommendation accuracy but poor diversity, while HC algorithm has good diversity but low accuracy. In order to solve the dilemma in accuracy and diversity, some hybrid recommendation algorithm have been proposed. This paper has mainly focused on the hybrid recommendation algorithm HHM, and pointed out its shortcomings. Based on the reconsideration of the effect of item popularity in the recommendation process, an improved hybrid recommendation algorithm using dual parameter called IHM was proposed. The particle swarm optimization (PSO) algorithm was applied to the parameter optimal of the hybrid recommendation algorithm to obtain the parameters of the algorithm. Experiments on 3 real datasets indicated that the IHM algorithm is better than HHM algorithms in terms of the recommendation accuracy, diversity and novelty. Meanwhile, the IHM algorithm can also improve the recommendation for items with lower popularity and solve the cold start problem. [ABSTRACT FROM AUTHOR]

In this paper, metallic powder coatings (MPC) were investigated as base powder coatings incorporating metallic flakes, providing finishes with a sparkly metallic effect. While MPC offers environmental advantages over liquid coatings by eliminating the usage of solvents, it presents challenges in achieving an intensified and stable metallic effect required by high-end products. This is primarily due to the limitations of the friction-based bonding technique, such as non-selective heating, employed in the current commercial production of MPC. To address this challenge, a microwave-based bonding method was developed that utilizes microwave energy as the heating source instead of stirring friction. This innovative approach leverages the selective heating properties of microwaves to produce qualified MPCs suitable for high-end products. Compared to the current friction-based method with a heating rate of approximately 4 ∘ C/min, microwave heating achieved a significantly faster heating rate of approximately 16 ∘ C/min, owing to the interface polarization effect. The microwave heating engendered a heightened efficacy in forging bonds between coating particles and Al flakes. As a consequence, in scenarios where equal weight percent of Al flakes was introduced, the microwave-treated specimens evinced a stronger metallic effect and enhanced stability compared to friction-heated ones. Furthermore, three-dimensional images of the Al flakes in the coating confirmed that microwave-heated films manifested an elevated flip-flop effect. Tribocorrosion test outcomes underscored that microwave-heated films exhibited higher open circuit potentials (OCP), indicating superior corrosion resistance, alongside better wear resistance compared to friction-heated ones. The microwave-based method obtained stronger and more stable MPCs with better corrosion and wear resistance, showing the promising potential for the expansion of MPC applications into the domain of high-end commodities. [Display omitted] • Innovatively using 2.45 GHz microwaves for heating/bonding metallic powder coatings. • Interface polarization of microwaves greatly improved bonding efficiency. • Microwave heating enhanced film stability and intensity significantly. • Microwave heating improved film wear/corrosion resistance vs. friction heating. [ABSTRACT FROM AUTHOR]

Background: The Asian yellow pond turtle (Mauremys mutica) is an important commercial freshwater aquaculture species in China. This species is a highly sexually dimorphic species, with males growing at a faster rate than females and exhibits temperature-dependent sex determination (TSD), in which the incubation temperature during embryonic development determines the sexual fate. However, the mechanisms of the sex determination or sex differentiation in the Asian yellow pond turtle are remain a mystery. Results: Temperature-specific gonadal transcriptomics of the Asian yellow pond turtle were performed during the thermosensitive period (stage 15) using RNA-seq technology to identify candidate genes that initiate gonadal differentiation. We uncovered candidates that were the first to respond to temperature. These candidates were sexually dimorphic in expression, reflecting differences in gonadal (Cirbp, Runx1) and germline differentiation (Vasa, Nanos1, Piwil2), gametogenesis (Hmgb3, Zar1, Ovoinhibitor-like, Kif4), steroid hormone biosynthesis (Hsd17b5, Hsd17b6), heat shock (Dnajb6, Hsp90b1, Hsp90aa1) and transient receptor potential channel genes (Trpm1, Trpm4, Trpm6, Trpv1). Conclusions: Our work will provide important genetic information to elucidate the mechanisms of sex control in the Asian yellow pond turtles, and will contribute important genetic resources for further studies of temperature-dependent sex determination in turtles. [ABSTRACT FROM AUTHOR]

The spectrum is a key environmental factor, and light-emitting diodes (LEDs) can influence the growth and development of crustaceans by altering the composition of the spectrum. This study conducted a 30-day experiment to investigate the effects of five LED spectra (red, yellow, blue, green, and white light) on the growth, antioxidant and immune enzyme activities, stress hormone levels, and the expression of α-amylase (α-AMY), ecdysone receptor (EcR) and retinoid X receptor (RXR) genes in juvenile redclaw crayfish (Cherax quadricarinatus). The results show that the survival rate of juveniles is markedly higher in the yellow and red-light groups than in the other three groups (P < 0.05). The green light group exhibits the lowest survival rate, yet it demonstrates the highest weight gain rate and specific growth rate. Regarding enzyme activity and hormone levels, the yellow light group shows the lowest malondialdehyde content, with higher superoxide dismutase and acid phosphatase activity than the other groups; no significant differences are observed in lysozyme activity among the groups (P > 0.05). The melatonin content in the green and blue light groups is significantly higher than that in the other three groups (P < 0.01). In terms of growth gene expression, the expression of α-AMY, EcR, and RXR in juvenile C. quadricarinatus is regulated by the spectrum. In conclusion, when raised under the yellow light spectrum, juvenile C. quadricarinatus displays elevated survival rates, rapid growth, and robust antioxidant and immune defenses. This study provides important technical parameters for optimizing and enhancing the industrial cultivation of juvenile C. quadricarinatus. [ABSTRACT FROM AUTHOR]

Aims: Soil organic carbon (SOC) stability greatly affects soil carbon sequestration capacity and carbon emissions, is related to soil bacterial communities, but it remains unclear whether such relationships exist in alpine wetland biogeomorphic succession. Methods: Here, we used a space-for-time approach across hydrological gradients, and alpine wetland succession can be divided into three types: "Swamp" (S), "Swamp Meadow" (SM), and "Meadow" (M) to examine the dynamics change of SOC fractions and bacterial communities. Results: The succession from S-SM-M resulted in decreased SOC stability (SM and M decreased by 18.65% and 31.88% compared to S). Furthermore, the decrease in SOC stability was primarily due to the decrease in soil moisture during succession and moisture-induced changes in bacterial community structure. e.g., the relative abundance of Proteobacteria decreased significantly by 40.99% and 52.87% in SM and M, while the relative abundance of Acidobacteria increased by 43.49% and 185.04% in SM and M compared to S. Co-occurrence network and random forest analyses further identified that changes in keystone taxa of bacteria, including Deltaproteobacteria, Acidimicrobiia, Bacteroidia and Gammaproteobacteria, were associated with SOC stability. Conclusions: In conclusion, bacteria shifted their community composition to reduce SOC stability in response to soil moisture variations during succession, and underscores the importance of identifying keystone taxa that are crucial for maintaining SOC stability. [ABSTRACT FROM AUTHOR]

• The phyllosphere microflora community changed rapidly during freeze–thaw period. • The bacterial communities mainly responded to changes of environmental factors, whereas the fungal communities were affected by both environmental factors and litter quality factors. • The bacterial communities were similar between woody litter and herbaceous litter, whereas the fungal communities differed obviously. Litter decomposition plays an important role in the nutrient cycle of terrestrial ecosystems. The alpine wetland has a high litter accumulation rate and a slow degradation rate, which is extremely sensitive to changeable freeze–thaw patterns against the background of global climate change. Freeze-thaw process is a common natural phenomenon in middle-high latitudes and high altitudes. Hydrothermal changes caused by freezing and thawing process affect the survival and physiological characteristics of microorganisms, and then affect the decomposition process of litters. The alpine wetland could be an ideal example for wetland in high altitude to study the mechanism of microbial community structure and function during litter composition during freeze–thaw process. Moreover, seldom has research in the whole process in the fields. The bacterial and fungal communities were analyzed in three different Carex litter decomposition stages—fresh, four-, and six-month—during the freeze–thaw period using 16/18S rDNA pyrosequencing. Phyllosphere microflora had identified rapid changes in the structure and function. Bacteria were mainly influenced by environmental factors (air temperature, soil moisture), and were significantly related to the degradation of litter lignin and the change of C/N ratio. Fungi were affected by both litter quality and environmental factors, and were significantly related to the degradation of cellulose and the change of C/N ratio. Moreover, phyllosphere organisms, including bacteria (Cryobacterium and Paracoccus members) and fungi (Mrakia , Mrakiella , and Naganishia), were replaced by communities with specific metabolic capabilities to adapt to each particular decomposition stage. Ilumatobacter and the fungal genera, Mycosphaerella and Athelia were characteristic of four-month-old litter samples, whereas Brevundimonas , Paracoccus and Nigrospora were characteristic of six-month-old litter samples. Our results suggest that the bacterial community structures of Carex and forest litter during initial decomposition stages may be similar but that their fungal community structures may differ substantially. [ABSTRACT FROM AUTHOR]

• Flexural strength and compressive strength of UHPC before and after cryogenic attack were studied. • Cryogenic damage variable of UHPC were investigated. • Fracture characteristics and micromorphology of UHPC were analyzed. As one of the most common extreme environments, cryogenic temperature will directly threaten the structural safety of normal service concrete, and engender the premature deterioration of the structure performance. In this paper, steel fiber, polypropylene fiber, and polyvinyl alcohol fiber were selected to prepared ultra-high-performance concrete (UHPC), and the effects of different fibers on flexural strength and compressive strength of UHPC subjected to cryogenic attack were investigated. The results indicated that the addition of steel fiber and PVA fiber improved the flexural strength and compressive strength of UHPC. After the cryogenic attack, the flexural strength of UHPC increased by 70.06% with the increase of length-to-diameter ratio of steel fiber, and the peak deflection increased from 0.501 mm ~ 0.919 mm to 0.609 mm ~ 1.302 mm. Conversely, the flexural strength of UHPC with PVA fiber and PP fiber decreased by 33.76% and 33.18%, respectively. The peak deflection of UHPC with PVA fiber decreased from 0.106 mm to 0.064 mm. When the length-to-diameter ratio of steel fiber was 65, UHPC reached the highest compressive strength of 173.06 MPa. The compressive strength of UHPC decreased after the cryogenic attack. PVA fiber and PP fiber absorbed a lot of water, which affected the cement hydration in UHPC, thus reducing the strength of UHPC. [ABSTRACT FROM AUTHOR]

The stability of C-S-H nanostructures with varying bulk CaO/SiO 2 (C/S) ratios under cryogenic attack (−170 °C) was experimentally studied by means of XRD, TG, SEM-EDS, 29Si MAS NMR, and FTIR. An efficient hydrothermal method was adopted to synthesize C-S-H by accelerating the thermodynamic equilibrium. The results show that the C-S-H atomic structure with a lower bulk C/S ratio is more stable under cryogenic attack. Ca2+ is more likely to leach out from C-S-H with a high C/S ratio. An increase in the bound water fraction was also observed in C/S1.5. At the atomic level, the number of interlayer Ca2+ per tetrahedral site in C/S1.5 significantly decreased from 0.201 to 0.083. The number of vacant bridging sites in C/S2.0 declined from 0.208 to 0.178, probably indicating a slight polymerization. Based on the deconvolution results of 29Si MAS NMR spectra, three reaction equations were proposed to characterize these observed variations. [ABSTRACT FROM AUTHOR]

• The elastic modulus of C-S-H decreased after cryogenic attack. • The volumetric stability of C-S-H grains under cryogenic attack was highly related to C/S ratio. • The cryogenic attack resulted in the collapse of the intraglobular pores of C-S-H basic building blocks. The cryogenic attack (−170 °C) degradation mechanisms to cement-based materials have not reached an overwhelming consensus. This work aimed to reveal the degradation role of cryogenic attack to the physical properties of calcium-silicate-hydrate (C-S-H) with varying CaO/SiO 2 (C/S) ratios. The topographic features, nanomechanical property, and volumetric stability of C-S-H grains and the basic building blocks were progressively investigated by atomic force microscopy (AFM), AFM-based indentation, nitrogen adsorption, and short-term helium inflow. The results revealed that the cryogenic attack could lead to degradation to C-S-H itself even without the presence of water. Firstly, the elastic moduli of individual C-S-H phases such as Low-Density (LD) C-S-H and High-Density C-S-H decreased, this nanoscale mechanical degradation was consistent with the macroscopic mechanical degradation of cement-based materials. Secondly, microcracks formed in C-S-H phases under the cryogenic attack. These destructive microcracks were likely to form inside or between C-S-H grains, which was dependent on C/S ratios. Thirdly, the cryogenic attack resulted in collapse of the intraglobular pores, leading to volume shrinkage of C-S-H basic building blocks, which initiates the formation of local defects and microcracks. [ABSTRACT FROM AUTHOR]

Alpine wetlands can function as carbon sinks because of their high soil organic content and low decomposition rates. However, the effects of alpine wetland succession on soil structure and soil organic carbon (SOC) stability have rarely been reported. The objective of this study was to investigate the effects of vegetation succession on soil aggregate distribution, bulk soil carbon, aggregate-associated C, and intra-aggregate C fraction in the Bayinbuluk alpine wetland. Research sites were selected in adjacent swamp (S), swampy meadow (SM), and meadow (M) locations. Five soil aggregate fractions (>5000, 2000–5000, 250–2000, 53–250 and <53 μm) were separated using a modified Yoder method. The light fraction organic carbon (LFOC), coarse/fine intra-aggregate particulate organic matter carbon (iPOM-C), and mineral-associated organic matter carbon (mSOM-C) were isolated from soil aggregates. In the wetland succession sequence, the mean weight diameter of soil aggregates increased (from 4.16 to 4.63 mm) from S to SM, and then decreased (from 4.63 to 3.23 mm) from SM to M. The bulk soil carbon content initially increased (from 93 to 129 mg kg−1) from S to SM, and then decreased (from 129 to 54 mg kg−1) from SM to M. The same trends were found for the aggregate-associated C in different size aggregates. The coarse iPOM-C content (88–133 mg kg−1) was higher than the fine iPOM-C content (77–118 mg kg−1) in different size aggregates in S samples. In SM and M samples, however, the coarse iPOM-C contents (98–124 mg kg−1 (SM); 60–82 mg kg−1 (M)) were lower than the fine iPOM-C contents (129–151 mg kg−1 (SM); 71–103 mg kg−1 (M)). The ratio of coarse iPOM-C to fine iPOM-C content (ROC/F) exceeded 1 in S but was lower than 1 in SM and M. These results indicate that soil aggregation stability and SOC content increased and then decreased across the wetland succession sequence, and that ROC/F can be used as an indicator of changes in SOC content caused by wetland succession. • Mean weighted diameter presented a "Ʌ"-shaped tendency along wetland succession. • Swampy meadow had the highest bulk soil carbon and aggregate-associated carbon. • Swampy meadow can be preserved as a large amount of activated carbon. • Coarse/fine iPOM-C is an indicator of SOC change along wetland succession. [ABSTRACT FROM AUTHOR]

Simple Summary: The DKK gene family plays an important role in immune mechanisms and embryonic development, but studies on Pelodiscus sinensis have not been reported. In this study, for the first time in the context of P. sinensis, we analyzed the relevant features of the DKK gene family using bioinformatics methods and constructed transcriptional profiles and tissue expression profiles. The DKK1 and DKK3 genes were found to be highly expressed in the ovaries, while DKKL1 and DKK4 were significantly differentiated in the testes. In this study, we preliminarily investigated the function of the DKK gene family in the context of P. sinensis, and this study lays the foundation for further systematic research on the molecular mechanism of sex differentiation in P. sinensis. The DKK family is a canonical small family of WNT antagonists. Though recent studies have suggested that the DKK gene family may be involved in sex differentiation in Pelodiscus sinensis, there are still a lot of things about the DKK gene family that we do not know. In this study, we used bioinformatics methods to identify members of the DKK gene family in P. sinensis and analyzed their phylogeny, covariance, gene structure, structural domains, promoter conserved sites, signal peptides, gonadal transcription factors, transcriptional profiles, and tissue expression profiles. Additionally, qRT-PCR results were utilized for the validation and preliminary investigation of the function of the DKK gene family in P. sinensis. The results showed that the DKK gene family is divided into six subfamilies, distributed on six different chromosomal scaffolds containing different gene structures and conserved motifs with the same structural domains, and all of the members were secreted proteins. Our transcriptional profiling and embryonic expression analysis showed that DKKL1 and DKK4 were significantly expressed in the testes, whereas DKK1 and DKK3 were significantly upregulated in the ovaries. This suggests a potential function in sex differentiation in P. sinensis. Our results may provide a basic theoretical basis for the sex differentiation process in P. sinensis. [ABSTRACT FROM AUTHOR]

Simple Summary: The Asian yellow pond turtle (Mauremys mutica) is widely traded in China, and its artificial breeding has now become a major industry. However, the insufficient offspring supply and reproductive decline of farmed turtles make wild turtles more vulnerable. The present study was mainly designed to quantify the fecundity of M. mutica and attempt to screen for good reproductive performance in females. The parent–offspring relationships of all offspring in four consecutive years were confirmed using sixteen microsatellite loci. We also summarised the reproductive results of all females and counted the annual number of offspring and the variation in the number of offspring. The females were then divided into three types (stable, undulating and levelling off) according to the continuity. This study can provide the basis and materials for the creation of a good reproductive group and the study of the reproductive biology of turtles in M. mutica aquaculture. The Asian yellow pond turtle (Mauremys mutica) is widely traded in China, and its artificial breeding has now become a major industry. However, the insufficient offspring supply and reproductive decline of farmed turtles make the wild turtles more vulnerable. The present study was mainly designed to quantify the fecundity of M. mutica and attempt to screen for good reproductive performance in females. The genetic variability of the population and its genetic structure were also analysed. The parent–offspring relationships of all offspring in four consecutive years were confirmed using sixteen microsatellite loci. The genetic variability between the parents and offspring was low, and offspring of different years also showed little variability. We summarised the reproductive results of all females and counted the annual number of offspring and the variation in the number of offspring. The females were then divided into three types (stable, undulating and levelling off) according to the continuity. We selected seven females with good reproductive ability, which provided 16.94% of the annual contributions, while there were two females that had no offspring in four years. We also analysed the possible reasons for this difference and the importance of carrying out a family survey. This research can provide the basis and materials for the creation of a good reproductive group and the study of the reproductive biology of turtles in M. mutica aquaculture. [ABSTRACT FROM AUTHOR]

Simple Summary: In aquaculture, the survival and health of aquatic organisms are influenced greatly by external environmental factors. Photoperiod is one of the key environmental factors that affect the early growth, survival, metabolism, and immune system of crustaceans significantly. The aim of the present study was to investigate the impact of photoperiod on the growth, survival, enzyme activity, body color, and expression of growth-related genes in juvenile redclaw crayfish. Five photoperiod experimental groups were established (0L:24D, 6L:18D, 12L:12D, 18L:6D, and 24L:0D), each with three replicates, and reared for 30 days. The group with an 18L:6D photoperiod had higher juvenile crayfish survival rates, better growth performance, stronger antioxidant stress response, and immune defense capabilities. Additionally, artificial photoperiods altered the body color of the redclaw crayfish. The results of the present study lay a foundation for the elucidation of the mechanisms underlying photoperiod regulation of the physiological and biochemical responses of juvenile redclaw crayfish. Through a 30-day experiment, this study investigated the effects of five photoperiods (0L:24D, 6L:18D, 12L:12D, 18L:6D, and 24L:0D) on the survival, enzyme activity, body color, and growth-related gene expression of redclaw crayfish (Cherax quadricarinatus) juveniles. The results showed that C. quadricarinatus juveniles under 18L:6D and 24L:0D photoperiods exhibited the highest survival rate, which was significantly higher than the survival rates of juveniles under the other three photoperiods (p < 0.05). However, the 0L:24D group had the highest final body weight and weight gain rate, significantly surpassing those of the 12L:12D, 18L:6D, and 24L:0D groups (p < 0.05). Regarding enzyme activity and hormone levels, juveniles under the 18L:6D photoperiod exhibited relatively higher activity of superoxide dismutase (SOD), acid phosphatase (ACP), and lysozyme (LZM) enzymes than those under other photoperiods, but their levels of melatonin and cortisol were relatively low. In addition, the 24L:0D group showed the highest malondialdehyde (MDA) content. Analysis of gene expression levels revealed that retinoid X receptor (RXR) and α-amylase (α-AMY) genes in C. quadricarinatus juveniles exhibited significantly higher expression levels under the 18L:6D photoperiod than those under the other four photoperiods (p < 0.05). With increasing daylight exposure, the body color of C. quadricarinatus changed from pale blue to yellow–brown. In summary, C. quadricarinatus juveniles achieved high survival rates, good growth performance, strong antioxidant stress response, and immune defense capabilities under an 18 h photoperiod. Therefore, in the industrial seedling cultivation of redclaw crayfish, it is recommended to provide 18 h of daily light. Further, the study demonstrated the ability to manipulate the body color of C. quadricarinatus through controlled artificial photoperiods. These findings provide essential technical parameters needed for the industrial cultivation of C. quadricarinatus juveniles. [ABSTRACT FROM AUTHOR]

Male and female Chinese soft-shelled turtles (Pelodiscus sinensis) have sex-dimorphic growth patterns, and males have higher commercial value because of their larger size and thicker calipash. Thus, developing sex-specific markers is beneficial to studies on all-male breeding in P. sinensis. Here, we developed an accurate and efficient workflow for the screening of sex-specific sequences with ZW or XY sex determination systems. Based on this workflow, female and male P. sinensis reference genomes of 2.23 Gb and 2.26 Gb were obtained using de novo assembly. After aligning and filtering, 4.01 Mb female-specific sequences were finally identified. Subsequently, the seven developed sex-specific primer pairs were 100% accurate in preliminary, population, and embryonic validation. The presence and absence of bands for the primers of P44, P45, P66, P67, P68, and P69, as well as two and one bands for the PB1 primer, indicate that the embryos are genetically female and male, respectively. NR and functional annotations identified several sex-determining candidate genes and related pathways, including Ran, Eif4et, and Crkl genes, and the insulin signaling pathway and the cAMP signaling pathway, respectively. Collectively, our results reveal that a ZW-type sex-determination system is present in P. sinensis and provide novel insights for the screening of sex-specific markers, sex-control breeding, and the studies of the sex determination mechanism of P. sinensis. [ABSTRACT FROM AUTHOR]

Conventional thermoset powder coatings typically require curing at a high temperature of 190 °C for a minimum duration of 15 min, which poses challenges when applying them to heat-sensitive substrates and results in elevated energy costs. A solution known as low-temperature-curing powder coating (LCPC) has been developed to address this issue. By normally incorporating the curing catalyst into the coating system via hot extrusion, LCPC can achieve either a reduced curing temperature or a shortened curing period. However, the current extrusion method used for catalyst incorporation leads to undesirable side effects, such as compromised surface quality, shorter shelf-life and a narrower operational window for the hot-extrusion process involved in producing powder coatings. To overcome these challenges, a new strategy is proposed in this study, in which the tailor-made nano-catalyst is post-dry-blended into the powder coating instead of subjecting it to hot treatment with coating ingredients. This dry-blending catalyst (DBC), encapsulating nanosized fumed silica with catalysts by impregnation method, is introduced to the powder coating system before spraying, eliminating the need for hot-kneading into the powder coating system at the beginning. The DBC is attached to the surface of the particle realizing the interparticle contact mode and latening the catalysis. The dry-blended low-temperature-curing powder coating (DB-LCPC), containing a 0.03 % dosage of onium salt and 0.035 % of 2-methylimidazole, is identified as the optimum formulation due to its excellent surface quality, prominent chemical and mechanical characteristics. The sample successfully achieved low-temperature curing or a shortened curing time while maintaining excellent mechanical properties and chemical resistance. Furthermore, it exhibited superior coating appearances and a longer shelf-life compared to the hot-extruded sample. This novel DBC method has the potential to greatly enhance the adoption of low-temperature-curing powder coatings. • A novel post-blending strategy is proposed to prepare low-cure powder coatings. • Interparticle contact mode of catalyst and coating particles are realized. • The diffusion between DBC and molten resin physically latened the catalytic curing. • DBC low-cure coatings show excellent mechanical property and chemical resistance. • DBC low-cure coatings exhibit superior coating appearances and a longer shelf-life. [ABSTRACT FROM AUTHOR]

Objectives: Lung adenocarcinoma (LUAD) exhibits a higher fatality rate among all cancer types worldwide, yet the precise mechanisms underlying its initiation and progression remain unknown. Mounting evidence suggests that long non-coding RNAs (lncRNAs) exert significant regulatory roles in cancer development and progression. Nevertheless, the precise involvement of lncRNA CYP4A22-AS1 in LUAD remains incompletely comprehended. Methods: Bioinformatics analyses evaluated the expression level of CYP4A22-AS1 in lung adenocarcinoma and paracancer. The LUAD cell line with a high expression of CYP4A22-AS1 was constructed to evaluate the role of CYP4A22-AS1 in the proliferation and metastasis of LUAD by CCK8, scratch healing, transwell assays, and animal experiments. We applied transcriptome and microRNA sequencing to examine the mechanism of CYP4A22-AS1 enhancing the proliferation and metastasis of LUAD. Luciferase reporter gene analyses, west-blotting, and qRT-PCR were carried out to reveal the interaction between CYP4A22-AS1, miR-205-5p/EREG, and miR-34c-5p/BCL-2 axes. Results: CYP4A22-AS1 expression was significantly higher in LUAD tissues than in the adjacent tissues. Furthermore, we constructed a LUAD cell line with a high expression of CYP4A22-AS1 and noted that the high expression of CYP4A22-AS1 significantly enhanced the proliferation and metastasis of LUAD. We applied transcriptome and microRNA sequencing to examine the mechanism of CYP4A22-AS1 enhancing the proliferation and metastasis of LUAD. CYP4A22-AS1 increased the expression of EREG and BCL-2 by reducing the expression of miR-205-5p and miR-34-5p and activating the downstream signaling pathway of EGFR and the anti-apoptotic signaling pathway of BCL-2, thereby triggering the proliferation and metastasis of LUAD. The transfection of miR-205-5p and miR-34-5p mimics inhibited the role of CYP4A22-AS1 in enhancing tumor progression. Conclusion: This study elucidates the molecular mechanism whereby CYP4A22-AS1 overexpression promotes LUAD progression through the miR-205-5p/EREG and miR-34c-5p/BCL-2 axes. [ABSTRACT FROM AUTHOR]

Simple Summary: Hibernation in turtle species is an adaptive survival strategy to colder winter conditions or food restrictions. However, the mechanisms underlying seasonal adaptions remain unclear. In this study, we isolated and performed scRNA-seq analysis on P. cantorii hemocytes in the active state and during hibernation to classify the hemocyte types and obtain the relevant cell maps. We identified the marker genes of each cell population and the differentiation pathways associated with their maturation. We also discovered different immune-related genes that might play crucial roles in hemocyte differentiation before and after hibernation. Our study aims to provide a reference dataset for the unified classification of P. cantorii hemocytes and improve our understanding of the immune system of P. cantorii. Hibernation in turtle species is an adaptive survival strategy to colder winter conditions or food restrictions. However, the mechanisms underlying seasonal adaptions remain unclear. In the present study, we collected hemocytes from Pelochelys cantorii and compared the molecular signature of these cells between the active state and hibernation period based on single-cell RNA sequencing (scRNA-seq) analysis. We found six cell types and identified a list of new marker genes for each cell subpopulation. Moreover, several heat shock genes, including the Hsp40 family chaperone gene (DNAJ) and HSP temperature-responsive genes (HSPs), were upregulated during the hibernation period, which predicted these genes may play crucial roles in the stress response during hibernation. Additionally, compared to hemocytes in the active state, several upregulated differentially expressed immune-related genes, such as stat1, traf3, and socs6, were identified in hemocytes during the hibernation period, thus indicating the important immune function of hemocytes. Therefore, our findings provide a unified classification of P. cantorii hemocytes and identify the genes related to the stress response, thereby providing a better understanding of the adaptive mechanisms of hibernation. [ABSTRACT FROM AUTHOR]

Simple Summary: The Asian giant soft-shelled turtle (Pelochelys cantorii), belonging to the order Testudines (family Trionychidae, genus Pelochelys), is one of the largest inland aquatic turtle species. However, due to excessive economic development, Pc. cantorii is critically endangered and rarely seen in the wild. As early as 1989, China listed the turtle as a key aquatic wildlife protection animal at the national level, but the conservation biology of Pc. cantorii has not been fully elucidated due to a lack of reference genomes. Here, based on a high-quality chromosome-level genome for Pc. cantorii, acquired by a combination of Illumina short-read, PacBio long-read and Hi-C scaffolding technologies in a previous study, we analyzed the evolutionary state of Pc. cantorii. Moreover, we found that several candidate genes associated with tumor suppression, growth and age were expanded, implicating their potential roles in the exceptional longevity of turtles. These findings will be an enabling resource for genetic and genomic studies to support fundamental insights into Pc. cantorii conservation. The Asian giant soft-shelled turtle, Pelochelys cantorii (Trionychidae), is one of the largest aquatic turtles in China and was designated as a First-Grade Protected Animal in China in 1989. Previous investigation based on a combination of Illumina short-read, PacBio long-read and Hi-C scaffolding technologies acquired a high-quality chromosome-level genome of Pc. cantorii. In this study, comparative genomic analysis between Pc. cantorii and 16 other vertebrate genomes indicated that turtles separated from the ancestor of archosaurians approximately 256.6 (95% highest posterior density interval, 263.6–251.9) million years ago (Mya) (Upper Permian to Triassic) and that Pc. cantorii separated from the ancestor of Pd. sinensis and R. swinhoei approximately 59.3 (95% highest posterior density interval, 64.3–54.3) Mya. Moreover, several candidate genes, such as VWA5A, ABCG2, A2M and IGSF1, associated with tumor suppression, growth and age were expanded, implicating their potential roles in the exceptional longevity of turtles. This new chromosome-level assembly has important scientific value in the study of conservation of Pc. cantorii and also enriches the evolutionary investigation of turtle species. [ABSTRACT FROM AUTHOR]

Simple Summary: We explored the effect of maternal size on offspring size and number using a 4-year dataset based on paternity analyses in Asian yellow pond turtle, Mauremys mutica, and found that the maternal size significantly affected the offspring number but not offspring size. The offspring size was significantly correlated with maternal age. Our results suggest that the offspring size-number trade-off theory does not apply to cultured M. mutica and also provides basic data for the efficient artificial breeding management of M. mutica in captivity. Offspring size-number trade-off is a critical component of life-history theory and is important for further understanding the reproductive strategies of animals. The relationship between this trade-off and maternal size has been explored in several turtle species, except for the Asian yellow pond turtle, Mauremys mutica. To investigate how the maternal condition affects offspring size and number, we explored the relationships among the maternal body size and the number and size of cultured M. mutica hatchlings using a 4-year dataset. Our results showed that different females not only produced different sizes of offspring but also produced different numbers of offspring. No trade-off in egg size number was detected. According to regression analysis, we did not find that the maternal body size significantly influenced the offspring mass; however, we detected that the offspring size was significantly correlated with the clutch size and maternal age. The mean body mass of offspring increased with maternal age, and the clutch size varied significantly over four years, which was correlated with offspring size, maternal body size and age. However, the number of offspring per female increased with the maternal plastron length rather than age. Our results were inconsistent with the optimal offspring size theory in that females did not increase their offspring size but rather increased the offspring number to increase their fitness, which will also provide a basis for the efficient cultivation management of turtles. [ABSTRACT FROM AUTHOR]

The article offers information on the study of parasitic diseases in China. Topics discussed include common parasitic diseases as per China's Ministry of Health in 1990 involves ascariasis, trichuriasis and hookworm; parasite control measures by China government like change in agricultural practice, and improved sanitation; and successful elimination of soil-transmitted helminth infections (STHs), schistosomiasis, and malaria.

Ultra-high Performance Concrete (UHPC) exposed to cryogenic temperatures typically fails in a brittle fashion, with a failure mode that is undesirable and catastrophic. In this study, the Thermal-dependent Brittleness (TDB) concept and its utilization for the evaluation of UHPCs exposed to different cryogenic temperatures were undertaken. Herein, flexural load-deflection curves of UHPC specimens and the absorbed energy evolution mechanism were analyzed. Moreover, the deformation and failure of UHPC specimens were also monitored utilizing changes in the Acoustic Emission (AE) signal. Results showed that whereas one-cycle flexural strength of UHPC specimen generally increased as test temperature reduced from 20 °C to −170 °C, a mixed effect on the toughness index was observed. The highest and lowest flexural toughness indexes were recorded for tests conducted at −110 °C and −170 °C, respectively. Moreover, the brittleness of UHPCs tested within −170 °C was accurately estimated by the newly proposed TDB all index. Finally, AE signals indicated that while tensile cracks exceeded shear cracks in specimens tested between 20 °C and −80 °C, there is a preponderance of shear cracks in specimens tested at −110 °C and −140 °C. [ABSTRACT FROM AUTHOR]

The effects of biochar on soil improvement have been widely confirmed, but its influence on soil microorganisms is still unclear. Elucidating the complex relationship and the community assembly processes of microorganisms under biochar addition is important to understand the ecological effects of this substance. We performed a one-time addition of biochar on aeolian soils and planted maize (Zea mays L.) continuously for 7 years. Afterwards, soil samples were collected, and the 16S/ITS rRNA gene sequencing technology was used to study changes in microbial community structure, network characteristics, and community assembly processes in the aeolian soils. We found that biochar addition significantly increased the maize yield and changed the soil microbial community composition (β-diversity), but had no significant effect on the microbial α-diversity. The addition of 31.5–126.0 Mg ha−1 of biochar led to a reduction of the rhizosphere bacterial network's edge number, average degree, and robustness, but had no significant effect on the fungal network properties. The bacterial community was controlled by deterministic processes, while fungi were mainly controlled by stochastic processes. The addition of 126.0 Mg ha−1 of biochar led to a transformation of the bacterial community's assembly processes from deterministic to stochastic. These results indicate that the stability of the rhizosphere bacterial community's complex network in aeolian soils diminishes under biochar addition, together changed the bacterial community's assembly processes. Fungi can instead effectively resist the environmental changes brought by biochar addition, and their network remains unchanged. These findings help clarify the effect of biochar addition on microbial interaction and assembly processes in aeolian soils characteristic of arid regions. Key points: • Biochar addition led to changes in the microbial community composition • Biochar addition reduced the network's stability of rhizosphere bacteria • Biochar addition changed the processes of the bacterial community assembly [ABSTRACT FROM AUTHOR]

This paper reports the flexural performance of ultra-high performance concrete (UHPC) exposure to six temperature conditions, including ambient temperature (A), after exposure to 200 °C (EA), in-situ −170 °C (DC), in-situ −170 °C after exposure to 200 °C (IDC), after exposure to −170 °C (AC), after exposure to 200 °C and −170 °C (AEC). The cracking characteristics of UHPC under the coupling effect of cryogenic and external load is identified with acoustic emission (AE) technology. The results show that DC condition is the most efficient in enhancing flexural strength and toughness due to frozen water and improved bond strength. A nonlinear relationship between first-peak deflection and first-peak flexural strength is observed because of the changed flexural modulus at different temperature conditions. The increasing shear cracks in linear-elastic stage is attributed to the fracture process of frozen water, which can account for the significant increase of first-peak strength at DC and IDC conditions. Cryogenic-induced ductility degradation is observed in the flexural behaviour of UHPCs at DC and IDC conditions, which is attributed to higher energy release rate. Furthermore, pre-exposure to 200 °C reduced the positive influence of cryogenic temperature on flexural performance and the negative effect of cryogenic temperature on ductility because of the initiated cracks around steel fibers. • Cracking behaviour of UHPC at cryogenic temperature is studied by acoustic emission. • Cryogenic-induced ductility degradation is due to more energy released in less time. • Pre-exposure to 200 °C reduces adverse effect of cryogenic temperature on ductility. [ABSTRACT FROM AUTHOR]

• Study performance of UHPC after alternating elevated and cryogenic attack (AECA) • Flexural Cracking behaviour of UHPC after AECAs is identified by acoustic emission. • AECA has dual effect of enhancement and deterioration on flexural property of UHPC. • Empirical equations are proposed to estimate flexural toughness and load of UHPC. This paper investigates the flexural performance of ultra-high-performance concrete (UHPC) subjected to a simulated lunar ground temperature environment between 200 °C and −170 °C termed as alternating elevated and cryogenic attack (AECA). Additionally, the cracking behavior during the failure process was characterized by acoustic emission (AE) technique. Compared with unexposed UHPC specimens, those exposed to AECA up to five cycles still exhibit superior flexural performance. The AE results imply that tensile cracks are mainly generated by the failure of cement matrix, and shear cracks are mainly attributed to the steel fiber–matrix debonding and steel fiber pull-out behaviour. AECA exhibits the dual effect of enhancement and deterioration on the flexural performance of UHPCs, and there is even a competitive relationship between the two effects. Due to the dual effect, cement matrix strength and bond strength between cement and steel fiber show different responses to AECA. Finally, four prediction equations that matched excellently with the experimental results are proposed to estimate the residual flexural load and compute the flexural toughness directly according to Newton-Leibniz law instead of integrating the area under the load–deflection curve. [ABSTRACT FROM AUTHOR]

For researches on flight delay from network perspective, we construct a directed weighted flight delay network and an innovative delay-propagating network to reveal the width and strength of flight delay. We use "width" to describe the range of delay, and "strength" to describe the growth of delay in the network. Then, we employ cumulative distributions of out-weight, which is consistent with air traffic network operation, to identify influential airports to the width and strength. Furthermore, we propose a state-of-the-art network decomposition method based on an airport's influence on the width and strength. We also analyze layer characteristic in the context of flight delay. Only layer I tends to maintain and increase flight delay. The physical and innovative concepts and methods that we propose can stimulate both empirical analyses on air traffic networks and studies on network-level delay control and reduction. [ABSTRACT FROM AUTHOR]

Simple Summary: Pelochelys cantorii is critically endangered and rarely seen in the wild, and only 13 adults are being kept in captivity in China. For the purpose of reinforcing the conservation and management of P. cantorii, the Pearl River Fisheries Research Institute (Chinese Fishery Academy of Sciences) successfully bred more than 800 turtles from 2015 to 2020. In this study, we developed and characterized 10 simple sequence repeat markers from the RNA transcriptome of P. cantorii, established two multiplex PCR systems, and obtained the genetic structure and genetic diversity of the artificially conserved population. The aim was to obtain viable second-generation P. cantorii with the highest genetic diversity to implement population recovery plans for this species. To understand the genetic structure of the protected turtle species Pelochelys cantorii we used transcriptome data to design more than 30,000 tri- and tetranucleotide repeat microsatellite primer pairs, of which 230 pairs were used for laboratory experiments. After two screenings, only 10 microsatellite markers with good specificity, high amplification efficiency, and polymorphisms were obtained. Using the selected primers, two multiplex PCR systems were established to compare and analyze the genetic diversity of artificially assisted breeding generations from four parents (two females and two males) continuously bred over two years. A total of 25 alleles were detected among the 10 microsatellite loci of the offspring. The polymorphism information content (PIC) was 0.313–0.674, with an average of 0.401, among which two loci were highly polymorphic (PIC ≥ 0.5). The number of alleles was 2–5 and the number of effective alleles was 1.635–3.614. The observed heterozygosity was 0.341–0.813, with an average of 0.582, whereas the average expected heterozygosity was 0.389–0.725, with an average of 0.493. Moreover, on the basis of Nei's genetic distance and the Bayesian clustering algorithm, the 182 offspring were divided into two subgroups, and the results corresponded to the two maternal lines. This is the first study to investigate the molecular markers of P. cantorii, and the results obtained can be used to protect genetic resources and provide a genetic basis for the design of population recovery plans. [ABSTRACT FROM AUTHOR]

HMGB2, a member of the high-mobility group (HMG) proteins, was identified as a male-biased gene and plays a crucial role in the germ cells differentiation of mammals. However, its role in spermatogenesis of turtle is still poorly understood. Here, we cloned the Pelodiscus sinensis HMGB2 and analyzed its expression profile in different tissues and in testis at different developmental ages. P. sinensis HMGB2 mRNA was highly expressed in the testis of 3-year-old turtles (P < 0.01), but was hardly detected in ovaries and other somatic tissues. The results of chemical in situ hybridization (CISH) showed that HMGB2 mRNA was specifically expressed in germ cells, where it was mainly distributed in round spermatids and sperm, but not detected in somatic cells, spermatogonia, primary spermatocytes, or secondary spermatocyte. The relative expression of HMGB2 also responded to seasonal changes in testis development in P. sinensis. In different seasons of the year, the relative expression of HMGB2 transcripts in the testis of 1 year and 2 year olds showed an overall upward trend, whereas, in the testis of 3 year old, it peaked in July and then declined in October. Moreover, in April and July, with an increase in ages, the expression of HMGB2 transcripts showed an upward trend. However, in January and October, there was a decline in expression in testis in 3-year-old turtles. These results showed that HMGB2 is closely related to spermatogenesis in P. sinensis. [ABSTRACT FROM AUTHOR]

Simple Summary: Gonadal cell lines possess the abilities of self-renewal and differentiation, being used as an efficient tool to analyzing the genes' functions involved in sex differentiation and gametogenesis. Although some significant achievements have been obtained in the gonadal cells' culture or manipulation across multiple phyla including teleost and mammals, there is limited study on gonadal cell manipulation in turtles. In this study, we isolated an ovarian cell line (fGSCs), from the juvenile Asian yellow pond turtle in vitro. The cultured fGSCs were characterized with germline stem cell specific markers' expression using transcriptome sequencing on Illumina platform, reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence (IF). Our study aims to provide a valuable tool to elaborate the molecular mechanisms behind germ cells development, differentiation and oogenesis in the turtle even in reptiles, and also, the established cell line has potential applications to enrich the conservation strategy of aquatic animal germplasm resources. Gonadal cell lines possess the abilities of self-renewal and differentiation, being used as an efficient tool to analyzing the genes' functions involved in sex differentiation and gametogenesis. Although some significant achievements have been obtained in the gonadal cells' culture or manipulation across multiple phyla including teleost and mammals, there is limited study on gonadal cell manipulation in turtles. In this study, we established a new ovarian cell line from the young Asian yellow pond turtle (Mauremys mutica), which exhibited a normal diploid karyotype with high alkaline phosphatase activity. The cell line, designated as YTO2, was then characterized through the analysis of gene expression profiles. The transcriptome analysis and the reverse transcription polymerase chain reaction (RT-PCR) showed that the cells expressed germline genes such as tdrd7, nanos1, klf5, igtb1, hsd17b4 and rad51. Moreover, the immunostaining showed that the germ cell markers, Tdrd7 and Rad51 proteins, were detected predominant in cytoplasm of perinuclear region, while proliferation marker, PCNA, was dominantly observed in the nuclei of cultured cells. Intriguingly, the cells could respond to the retinoic acid induction with significantly increasing the expression level of some meiosis genes, including vasa, dazl, figla, and dmc1. Furthermore, YTO2 cells could be efficiently transfected with the pHBAd-BHG-EGFP adenovirus and properly expressed the exogenous genes. To sum up, an ovarian cell line of the Asian yellow pond turtle had been established and could be stably propagated under in vitro culture condition, as well as being capable of efficiently expressing the exogenous gene tdrd7. This cell line would provide a valuable tool to elaborate the molecular mechanisms behind germ cells development, differentiation and oogenesis in the turtle, even in reptiles. [ABSTRACT FROM AUTHOR]

Simple Summary: Turtles have been on Earth for 300 million years, but their survival has been challenged as human activity has expanded. The results of a census and statistical analysis of artificially domesticated aquatic turtles in 15 provinces of China showed that 29 species were aquatic turtles native to China and a large number of exotic aquatic turtles are domesticated in China. This paper presents the current situation and problems of aquaculture and conservation of aquatic turtles in major provinces of China, and puts forward some suggestions for the conservation and management of aquatic turtles. China is a major country in turtle cultivation and has a long history of artificial breeding of turtles. In this study, a census and statistical analysis of artificially domesticated aquatic turtles in 15 provinces of China were conducted. The results showed that 29 species were aquatic turtles native to China, accounting for approximately 9% of the world's total, and a large number of exotic aquatic turtles are also domesticated in China. The present situation of artificial breeding and protection of aquatic turtles in major provinces of China is shown, and existing problems are also put forward, with suggestions for the protection and management of aquatic turtles. [ABSTRACT FROM AUTHOR]

Simple Summary: Chinese soft-shell turtle (Pelidiscus sinensis) is a widely farmed aquatic reptile in China. It has of high nutritional, pharmaceutical, and economic value, but wild Chinese soft-shell turtle has been faced with an extreme decline of populations. Thus, it is of great significance to study the germ cells biology and develop the techniques for turtle breeding and genetic resource preserving. Nanog is a homeodomain-containing transcription factor, and it plays a vital role in maintaining the pluripotency of embryonic stem cells; there is a lack of reporting on the Nanog gene in reptile. In this study, the cDNA sequence and promoter of a Nanog gene was identified in P. sinensis, designed as PsNanog. PsNanog gene products were mainly expressed in gonads and were especially rich in ovary. Particularly, PsNanog mRNA and protein was exclusively expressed in germ cells in ovary and testis. Collectively, this is the first report on the gene structure and expression of Nanog in turtle, which may lay a foundation for further functional analysis of the Nanog in turtle, even in the reptiles. Further, PsNanog probably has the conserved and divergent function in regulating cell pluripotency and germ cell development in turtle, compared with other species, including teleosts and mammals. Nanog is a homeodomain-containing transcription factor, and it plays a vital role in maintaining the pluripotency of embryonic stem cells. Nanog's function has been well studied in many species. However, there is lack of reporting on the Nanog gene in reptile. Here, we identified a 1032 bp cDNA sequence of a Nanog gene in Pelidiscus sinensis, known as PsNanog. PsNanog has a highly conserved HD domain and shares a high identity with that of Chelonia mydas and the lowest identity with Oryzias latipes. Similarly, PsNanog presented a tight cluster with C. mydas Nanog, but was far from those of teleosts. Additionally, we cloned a length of 1870 bp PsNanog promoter. Dual luciferase assay showed that the DNA fragment of −1560 to +1 exhibited a high promoter activity. The RT-PCR and RT-qPCR results showed that PsNanog was predominantly expressed in ovary, and then in testis. The in situ hybridization and immunohistochemical analysis showed that PsNanog was expressed in the early primary oocytes and the cytoplasm of the cortical region of stage VIII oocytes in ovary, and distributed in most stages of germ cells in testis. Collectively, the results imply that PsNanog probably has the conserved function in regulating germ cell development across phyla and is also a pluripotent cell gene and expressed in germ cells, which is similar to that in teleosts and mammals. [ABSTRACT FROM AUTHOR]

Simple Summary: Spermatogenesis in Pelodiscus sinensis has distinct seasonal characteristics. Spats1 acts a key function in germ cell differentiation in mammals, yet its study in P. sinensis has not been reported. Here, we cloned the coding sequences (CDS) of Spats1 for the first time and characterized its expression in different tissues. In addition, the expression characteristics of Spats1 in the testis during different seasons and the expression pattern in embryos and adults after steroid hormone treatment were also investigated. The present research provides a preliminary study on the physiological regulation of Spats1 in P. sinensis, and lays the foundation for further systematic investigation of the molecular mechanisms of spermatogenesis and release in P. sinensis. Spats1 (spermatogenesis-associated, serinerich 1) has been characterized as a male-biased gene which acts an important role in the germ cell differentiation of mammals. Nevertheless, the function of Spats1 in the Chinese soft-shelled turtle (P. sinensis) has not yet been reported. To initially explore the expression of Spats1 in P. sinensis and its response to sex steroid treatment, we cloned the CDS of Spats1 for the first time and analyzed its expression profile in different tissues, including the testes in different seasons. The Spats1 cDNA fragment is 1201 base pairs (bp) in length and contains an open reading frame (ORF) of 849 bp, which codes for 283 amino acids. Spats1 mRNA was highly expressed in the testes (p < 0.01) and barely detectable in other tissues. In P. sinensis, the relative expression of Spats1 also responsive to seasonal changes in testis development. In summer (July) and autumn (October), Spats1 gene expression was significantly higher in the testes than in other seasons (p < 0.05). Spats1 mRNA was found to be specifically expressed in germ cells by chemical in situ hybridization (CISH), and it was mainly located in primary spermatocytes (Sc1), secondary spermatocytes (Sc2) and spermatozoa (St). Spats1 expression in embryos was not significantly changed after 17α-methyltestosterone (MT)and 17β-estradiol (E2) treatment. In adults, MT significantly induced Spats1 expression in male P. sinensis. However, the expression of Spats1 in testes was not responsive to E2 treatment. In addition, the expression of Spats1 in females was not affected by either MT or E2 treatment. These results imply that Spats1 is a male-specific expressed gene that is mainly regulated by MT and is closely linked to spermatogenesis and release in P. sinensis. [ABSTRACT FROM AUTHOR]