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Aims This study aimed to investigate the impact of temperature on the intestinal microbiota of largemouth bass using 16S rRNA gene amplicon sequencing, focusing on the under-explored role of abiotic factors in shaping the gut microbial community. Methods and results Five water temperature groups (20.0 ± 0.2°C, 25.0 ± 0.2°C, 28.0 ± 0.2°C, 31.0 ± 0.2°C, and 35.0 ± 0.2°C) were established, each with three replicates. Significant variations in intestinal bacterial community composition were observed across these conditions. Elevated temperatures (31.0 ± 0.2°C and 35.0 ± 0.2°C) led to an increase in opportunistic pathogens such as OTU180 Vibrio and OTU2015 Vogesella (P  < 0.05). Species correlation network analysis showed a shift toward more positive relationships among intestinal microbes at higher temperatures (P  < 0.05). Ecological process analysis highlighted a greater role of ecological drift in microbial community structure at 31.0 ± 0.2°C and 35.0 ± 0.2°C (P  < 0.05). Conclusions The study suggests that higher temperatures may predispose largemouth bass to opportunistic pathogens by altering their intestinal microbiota. Effective water temperature management is crucial for largemouth bass aquaculture to mitigate pathogen risks and maintain a balanced intestinal microbiota. This research provides critical insights into the temperature–microbiota relationship and offers practical recommendations for aquaculture practices. [ABSTRACT FROM AUTHOR]

The elastic properties and solid solution strengthening of several Cu alloys that may be promising for high gradient applications were studied using ab initio calculations based on density functional theory. Specifically, the temperature and solute concentration dependence of elastic properties including bulk and shear moduli, thermal expansion coefficient, and heat capacity of these alloys were calculated. We found that the bulk and shear moduli are linearly dependent on the solute concentration in the dilute regime and change significantly for different Cu alloys. The thermal expansion coefficient and heat capacity are comparatively less sensitive to solute concentrations. Solid solution strengthening is observed to be linearly correlated with the change of lattice parameter of Cu. This work provides an in-depth understanding of the elastic properties of Cu alloys, which is key for predicting their performance at high gradient in normal conducting accelerating structures. [ABSTRACT FROM AUTHOR]

Protection against surface corrosion is essential for ensuring the reliability and long-term durability of uranium materials. Atomically thin two-dimensional (2D) nanomaterials, known for their unique chemical inertness, are particularly promising as anticorrosion coatings. The representative 2D nanomaterials from different classes (insulator, semimetal, semiconductor, and conductor), including BN, graphene, MoSe2, MoS2, and oxygen-passivated Ti2C layers (Ti2CO2 and Ti2CO), were selected to investigate their interactions with the UO2(111) surface using quantum mechanical calculations. Our results show that graphene and h-BN exhibit physical adsorption with the lowest binding energies, less than 1.0 J/m2. In contrast, MoS2 and MoSe2 demonstrate chemical adsorption in the range of 1.0 to 1.5 J/m2. The highest binding energy of 1.7 and 3.1 J/m2 was predicted for Ti2C-based MXenes (Ti2CO2 and Ti2CO, respectively). These results establish the MXene class as the most promising coating for UO2 among the 2D materials considered. It is worth noting that surface defects, whether induced by oxidation or reduction, can influence the strength of the coating, with the primary determinant being the nature of the 2D nanomaterial. [ABSTRACT FROM AUTHOR]

Micropterus salmoides rhabdovirus (MSRV) is a formidable pathogen, presenting a grave menace to juvenile largemouth bass. This viral infection frequently leads to epidemic outbreaks, resulting in substantial economic losses within the aquaculture industry. Unfortunately, at present, there are no commercially available vaccines or pharmaceutical treatments to combat this threat. In order to address the urgent need for therapeutic strategy to resist MSRV infection, the antiviral activity of natural product honokiol against MSRV was explored in this study. Firstly, cellular morphology was directly observed in an inverted microscope when treated with honokiol after MSRV infection. The results clarified that honokiol significantly lessened cytopathic effect (CPE) induced by MSRV and protected the integrity of GCO cells. Furthermore, the viral nucleic acid expression (G gene) was detected by reverse transcription real‐time quantitative PCR (RT‐qPCR) and the results indicated that honokiol significantly decreased the viral loads of MSRV in a concentration‐dependent manner, and honokiol showed a high antiviral activity with IC50 of 2.92 μM. Besides, honokiol significantly decreased the viral titre and suppressed apoptosis caused by MSRV. Mechanistically, honokiol primarily inhibited the initial replication of MSRV and discharge of progeny virus to exert anti‐MSRV activity. More importantly, in vivo experiments suggested that honokiol (40 mg/kg) expressed a fine antiviral activity against MSRV when administrated with intraperitoneal injection, which led to a notable 40% improvement in the survival rate among infected largemouth bass. In addition, it also resulted in significant reduction in the viral nucleic acid expression within liver, spleen and kidney at 2, 4 and 6 days following infection. What is more, 100 mg/kg honokiol with oral administration also showed certain antiviral efficacy in MSRV‐infected largemouth bass via improving the survival rate by 10.0%, and decreasing significantly the viral nucleic acid expression in liver, spleen and kidney of largemouth bass on day 2. In summary, natural product honokiol is a good candidate to resist MSRV infection and has promising application prospects in aquaculture. [ABSTRACT FROM AUTHOR]

Aeromonas hydrophila and A. veronii are widespread and important critical pathogenic bacteria in the aquaculture industry and cause severe economic damage. At present, magnolol has been proved to be a broad‐spectrum antibacterial activity, such as A. hydrophila, Staphylococcus aureus and Streptococcus mutans. In order to explore the cause of in vivo disease resistance of magnolol and promote its safe application in aquaculture, the pathological detection and changes in immune indicators of fish after feeding with magnolol were conducted in this paper. Results showed that the diets supplemented with magnolol (3 g magnolol/kg commercial feed) significantly increase the expression level of anti‐inflammatory cytokines (IL‐10, TGF‐β and IL‐4) in the liver of goldfish (p <.05). Additionally, the expression levels of proinflammatory cytokines (IL‐1β, IL‐8 and IFN‐γ) did not increase significantly. Subsequently, this study investigated the resistance of goldfish to A. hydrophila and A. veronii infection after feeding with magnolol. The results showed that the survival rates of treatment groups fed 3 g magnolol/kg commercial feed daily increased by 23.1% and 38.5% after 10 days post A. hydrophila and A. veronii (p =.0351) infection, respectively. Meanwhile, growth performance (body weight and length), major internal organs (liver, spleen, kidney and intestine) and the serum biochemistry indicators (ATL and AST) all exhibited no significant adverse effects after the goldfish fed with magnolol for 30 days. TP showed an increasing concentration in the treatment group (p <.05). Results of the mRNA expression of stress response indicated that the expression level of cyp1a and hsp70 was significantly down‐regulated after a 30‐day treatment (p <.05), and the two genes recovered to the similar level as the control group after a commercial feed diet. In brief, the diets supplemented with magnolol protected the host from the excessive immune response caused by A. hydrophila and A. veronii via enhancing its anti‐inflammatory capacity and had no adverse effects with feeding. [ABSTRACT FROM AUTHOR]

Topmouth culter (Culter alburnus) is an ecologically and economically important species belonging to the subfamily Culterinae that is native to and widespread in East Asia. Intraspecific variation of semi‐buoyant and adhesive eggs in topmouth culter provides an ideal opportunity to investigate the genetic mechanisms of spawning habits underlying the adaptive radiation of cyprinids in East Asia. In this study, we present a chromosome‐level genome assembly of topmouth culter and re‐sequenced 158 individuals from six locations in China covering three geographical groups and two egg type variations. The topmouth culter genome size was 1.05 Gb, with a contig N50 length of 17.8 Mb and anchored onto 24 chromosomes. Phylogenetic analysis showed that the divergence time of the Culterinae was coinciding with the time of initiation of the Asian monsoon intensification. Gene family evolutionary analysis indicated that the expanded gene families in topmouth culter were associated with dietary adaptation. Population‐level genetic analysis indicated clear differentiation among the six populations, which were clustered into three distinct clusters, consistent with their geographical divergence. The historical effective population size of topmouth culter correlated with the Tibetan Plateau uplifting according to the demographic history reconstruction. A selective sweep analysis between adhesive and semi‐buoyant egg populations revealed the genes associated with the hydration and adhesiveness of eggs, indicating divergent selection towards different hydrological environments. This study offers a high‐resolution genetic resource for further studies on evolutionary adaptation, genetic breeding and conservation of topmouth culter, providing insights into the molecular mechanisms for egg type variation of East Asian cyprinids. [ABSTRACT FROM AUTHOR]

Tilapia, as one of the fish widely cultured around the world, is suffering severe impact from the streptococcus disease with the deterioration of the breeding environment and the increasing of breeding density, which brings serious economic loss to tilapia farming. In this study, the surface immunogenic protein (Sip) of Streptococcus agalactiae (S. agalactiae) was selected as the potential candidate antigen and connected with bacterial nano cellulose (BNC) to construct the nanocarrier subunit vaccine (BNC-rSip), and the immersion immune effects against S. agalactiae and Streptococcus iniae (S. iniae) in Nile tilapia were evaluated on the basis of the serum antibody level, non-specific enzyme activity, the immune-related gene expression and relative percent survival (RPS). The results indicated that Sip possessed the expected immunogenicity according to the immunoinformatic analysis. Compared with the rSip group, BNC-rSip significantly induced serum antibody production and improved the innate immunity level of tilapia. After challenge, the RPS of BNC-rSip groups were 78.95% (S. agalactiae) and 67.86% (S. iniae), which were both higher than those of rSip groups,31.58% (S. agalactiae) and 35.71% (S. iniae), respectively. Our study indicated that BNC-rSip can induce protective immunity for tilapia through immersion immunization and may be an ideal candidate vaccine for controlling tilapia streptococcal disease. [ABSTRACT FROM AUTHOR]

Background: Pathogen infections seriously affect host health, and the use of antibiotics increases the risk of the emergence of drug-resistant bacteria and also increases environmental and health safety risks. Probiotics have received much attention for their excellent ability to prevent pathogen infections. Particularly, explaining mechanism of action of probiotics against pathogen infections is important for more efficient and rational use of probiotics and the maintenance of host health. Results: Here, we describe the impacts of probiotic on host resistance to pathogen infections. Our findings revealed that (I) the protective effect of oral supplementation with B. velezensis against Aeromonas hydrophila infection was dependent on gut microbiota, specially the anaerobic indigenous gut microbe Cetobacterium; (II) Cetobacterium was a sensor of health, especially for fish infected with pathogenic bacteria; (III) the genome resolved the ability of Cetobacterium somerae CS2105-BJ to synthesize vitamin B12 de novo, while in vivo and in vitro metabolism assays also showed the ability of Cetobacterium somerae CS2105-BJ to produce vitamin B12; (IV) the addition of vitamin B12 significantly altered the gut redox status and the gut microbiome structure and function, and then improved the stability of the gut microbial ecological network, and enhanced the gut barrier tight junctions to prevent the pathogen infection. Conclusion: Collectively, this study found that the effect of probiotics in enhancing host resistance to pathogen infections depended on function of B12 produced by an anaerobic indigenous gut microbe, Cetobacterium. Furthermore, as a gut microbial regulator, B12 exhibited the ability to strengthen the interactions within gut microbiota and gut barrier tight junctions, thereby improving host resistance against pathogen infection. 9wW3zJp3HpFrGEQCmLVC3S Video Abstract [ABSTRACT FROM AUTHOR]

We report a lowering of work function for lanthanum hexaboride (LaB6) by monolayer hexagonal boron nitride (hBN) coating. Photoemission electron microcopy (PEEM) and thermionic emission electron microscopy (TEEM) both revealed that the hBN coated region of a LaB6 (100) single crystal has a lower work function compared to the bare (i.e., non-coated) and graphene coated regions. A broad and uniform brighter image of the hBN coated region in PEEM was quantitatively supported by a 0.4 eV decrease in the work function in photoelectron spectra compared to the bare region. TEEM results were consistent in that the hBN coated region exhibited thermionic emission at 905 °C, whereas the bare and graphene coated regions did not. A larger decrease in the work function for hBN coated LaB6 (100) compared to graphene coated LaB6 (100) was qualitatively supported by our density functional theory calculations. Adding an oxide layer in the calculations improved consistency between the calculation and experimental results. We followed up our calculations with synchrotron-radiation x-ray photoelectron spectroscopy and confirmed the presence of an oxide layer on our LaB6. [ABSTRACT FROM AUTHOR]

Protection of free-electron sources has been technically challenging due to lack of materials that transmit electrons while preventing corrosive gas molecules. Two-dimensional materials uniquely possess both of required properties. Here, we report three orders of magnitude increase in active pressure and factor of two enhancement in the lifetime of high quantum efficiency (QE) bialkali photocathodes (cesium potassium antimonide (CsK2Sb)) by encapsulating them in graphene and thin nickel (Ni) film. The photoelectrons were extracted through the graphene protection layer in a reflection mode, and we achieved QE of ~ 0.17% at ~ 3.4 eV, 1/e lifetime of 188 h with average current of 8.6 nA under continuous illumination, and no decrease of QE at the pressure of as high as ~ 1 × 10–3 Pa. In comparison, the QE decreased drastically at 10–6 Pa for bare, non-protected CsK2Sb photocathodes and their 1/e lifetime under continuous illumination was ~ 48 h. We attributed the improvements to the gas impermeability and photoelectron transparency of graphene. [ABSTRACT FROM AUTHOR]

Largemouth bass virus (LMBV) is a systemic viral pathogen that can cause high mortality rates in cultivated largemouth bass. However, no treatment is currently approved. Therapeutic strategies against LMBV infection are urgently needed. In this study, we investigated the antiviral activity of piperine against LMBV in vitro and in vivo. In vitro antiviral activity assay showed that 210.28 μM piperine significantly decreased LMBV major capsid protein (MCP) gene expression in epithelioma papulosum cyprinid (EPC) cells by a maximum inhibitory rate of >95%. Piperine treatment inhibited LMBV replication in a dose‐dependent manner, with the half‐maximal activity (IC50) of 34.61 μM. Moreover, piperine significantly decreased the viral titers and cytopathic effects (CPE), contributing to the protection of infected cells. With regard to the steps of piperine affecting the life cycle of viruses, piperine had a direct inactivating effect on LMBV. During the virus adsorption phase, piperine prevented the adsorption of LMBV to EPC cells. Furthermore, piperine played an antiviral role mainly in the later stages of viral infection (4–8 h). To further evaluate the antiviral activity of piperine against LMBV in vivo, largemouth bass as a model organism was carried out in relevant experiments. Intraperitoneal injection of piperine (25 mg/kg) effectively improved the survival rate of LMBV‐infected largemouth bass by 20%. In addition, RT‐qPCR results of viral replication in liver, spleen, kidney, gill and swim bladder tissues showed that piperine significantly inhibited LMBV replication in vivo, thus protecting largemouth bass from LMBV‐induced death. Together, our results suggested that piperine is a therapeutic and preventative agent against LMBV infection. [ABSTRACT FROM AUTHOR]

Protection of free-electron sources has been technically challenging due to lack of materials that transmit electrons while preventing corrosive gas molecules. Two-dimensional materials uniquely possess both of required properties. Here, we report three orders of magnitude increase in active pressure and factor of two enhancement in the lifetime of high quantum efficiency (QE) bialkali photocathodes (cesium potassium antimonide (CsK2Sb)) by encapsulating them in graphene and thin nickel (Ni) film. The photoelectrons were extracted through the graphene protection layer in a reflection mode, and we achieved QE of ~ 0.17% at ~ 3.4 eV, 1/e lifetime of 188 h with average current of 8.6 nA under continuous illumination, and no decrease of QE at the pressure of as high as ~ 1 × 10–3 Pa. In comparison, the QE decreased drastically at 10–6 Pa for bare, non-protected CsK2Sb photocathodes and their 1/e lifetime under continuous illumination was ~ 48 h. We attributed the improvements to the gas impermeability and photoelectron transparency of graphene. [ABSTRACT FROM AUTHOR]

Background: Rice-fish symbiosis, as an ecological and green aquaculture model, is an effective measure to relieve the environmental stress from intensive aquaculture. Compared with traditional aquaculture, the altered rearing pattern and environment will make differences in muscle nutrient and quality, intestinal microbiota, body metabolism, and even disease resistance in fish. Results: To investigate this, we explored the differences between rice-tilapia (aRT and bRT) and tank-tilapia (aTT and bTT) models at the periods before and after rice flowering using 16S rRNA sequencing and untargeted metabolomics. The results showed that compared with tilapia reared in the tank model, the fish body length and weight, the muscle total umami amino acid, and monounsaturated fatty acid content were obviously higher in the rice-fish model, especially after rice flowering. Compared with other groups, the intestinal microbiota diversity of fish in the bRT group was significantly higher; the dominant microbiota was Bacteroidetes and Firmicutes at the phylum level, Bacteroides and Turicibacter at the genus level, and the relative abundances of Gram-negative, potentially pathogenic, and stress-tolerant bacteria were the highest, lowest, and highest, respectively. Besides, the differential metabolite analysis indicated that rice-fish symbiosis improved the metabolic profiles and modulated the metabolic pathways in tilapia. Moreover, the correlation analysis of 16S sequencing and metabolomics showed that Bacteroides showed a positive correlation with many metabolites related to amino acid, fatty acid, and lipid metabolism. 2e2Pq8QQo51bRYuGfijeGG Video Abstract Conclusions: In summary, rice flowering improves the tilapia muscle nutrient, intestinal microbiota diversity, and disease resistance and modulates the host metabolism to acclimatize the comprehensive environment in rice-fish symbiosis. Specifically, rice flowering alters the microbiota abundance involved in amino acid, fatty acid, and lipid metabolism, resulting in improving the muscle nutrient and quality through the crosstalk of gut microbial and host metabolism. Our study will provide not only new insight into the gut microbiota-metabolism-phenotype axis, but also strong support for the promotion and application of rice-fish symbiosis in aquaculture. [ABSTRACT FROM AUTHOR]

Micropterus salmoides rhabdovirus (MSRV) is a primary viral pathogen in largemouth bass aquaculture, which leads to tremendous economic losses yearly. Currently, there are no approved drugs for the treatment and control of this virus. Our previous studies screened the herb Magnolia officinalis from many traditional Chinese medicines, and we isolated and identified magnolol as its main active compound against multiple rhabdoviruses, including MSRV. On the basis of the structure–activity relationship and pharmacophore model of magnolol, two new magnolol derivatives, namely, hydrogenated magnolol and 2,2′-dimethoxy-magnolol, were designed and synthesized. Their anti-MSRV activities were systematically investigated both in vitro and in vivo. By comparing the half-maximal inhibitory concentration (IC50), it was found that hydrogenated magnolol possessed a higher anti-MSRV activity than magnolol and 2,2′-dimethoxy-magnolol, with an IC50 of 13.37 μM. Furthermore, hydrogenated magnolol exhibited a protective effect on the grass carp ovary (GCO) cell line by reducing the cytopathic effect induced by MSRV. Further studies revealed that hydrogenated magnolol did not directly impact virions or interfere with MSRV adsorption. It worked within the 6–8 h of the phase of virus replication. In vivo treatment of MSRV infection with magnolol and hydrogenated magnolol showed that they significantly improved the survival rate by 44.6% and 62.7%, respectively, compared to MSRV-infected groups. The viral load measured by the expression of viral glycoprotein in the organs including the liver, spleen, and kidney also significantly decreased when fish were intraperitoneally injected at a dose of 20 mg/kg. Altogether, the structural optimization of magnolol via hydrogenation of the propylene groups increased its anti-MSRV activity both in vitro and in vivo. These results may provide a valuable reference for anti-MSRV drug discovery and development in aquaculture. [ABSTRACT FROM AUTHOR]

Operation of normal conducting accelerator structures at high accelerating gradients is beneficial for many accelerator applications in basic science, industry, medicine, and National Security. RF breakdown is the major factor that limits the achievable accelerating gradients. Previous experiments on copper (Cu) have demonstrated that RF breakdown probability can be significantly decreased by hardening the material and alloying Cu with solutes such as silver (Ag). In this paper, we propose a figure-of-merit (FOM) that characterizes the ability of Cu alloys to withstand high-gradients. The FOM represents a trade-off between hardening through solid solution strengthening and the additional thermal stress induced by incremental RF pulse heating resulting from changes in electronic properties induced by alloying. We performed high-throughput ab initio calculations and computed the FOM for a large number of binary Cu alloys. Several promising candidate alloys for high-gradient accelerating structures were identified, such as CuAg, CuCd, CuHg, CuAu, CuIn, and CuMg. CuAg alloys have previously exhibited low RF breakdown rates in experiments. The results provide guidance for selecting alloys for the future high-gradient normal conducting accelerating structures operating at very high gradients. [ABSTRACT FROM AUTHOR]

Largemouth bass virus (LMBV) is one of the most devastating viral pathogens in farmed Largemouth bass. Aptamers are novel molecule probes and have been widely applied in the field of efficient therapeutic and diagnostic agents development. LMBV-infected fathead minnow cells (LMBV-FHM) served as target cells in this study, and three DNA aptamers (LBVA1, LBVA2, and LBVA3) were generated against target cells by SELEX technology. The selected aptamers could specifically bind to LMBV-FHM cells, with rather high calculated dissociation constants (K d) of 890.09, 517.22, and 249.31 nM for aptamers LBVA1, LBVA2, and LBVA3, respectively. Three aptamers displayed efficient antiviral activities in vitro. It indicates that the selected aptamers have great potentials in developing efficient anti-viruses treatments. The targets of aptamers LBVA1, LBVA2, and LBVA3 could be membrane proteins on host cells. The targets of aptamers (LBVA1, LBVA2, and LBVA3) come out on the cells surface at 8, 10, 8 h post-infection. As novel molecular probes for accurate recognition, aptamer LBVA3 could detect LMBV infection in vitro and in vivo , it indicates that the selected aptamers could be applied in the development of rapid detective technologies, which are characterized by high sensitivity, accuracy, and easy operation. [ABSTRACT FROM AUTHOR]

Uranium trichloride (UCl3) is actively researched to develop and improve applications ranging from molten salt reactors to actinide processing, including spent fuel reprocessing. Here, we report for the first time the crystal structure evolution between room temperature and melting point from in situ high-temperature neutron diffraction to quantify, for example, the thermal expansion of the hexagonal a and c lattice parameters. The results are compared with density functional theory calculations. The melting point of UCl3 is determined by differential scanning calorimetry to be 1108.2 ± 0.2 K. [ABSTRACT FROM AUTHOR]

Target identification is important for drug discovery. Unfortunately, no drug targets have been found in Ichthyophthirius multifiliis until now and further limited development of the novel drug for Ichthyophthiriasis. In this study, an iTRAQ‐based quantitative proteomic analysis was used to find the target of malachite green (MG), exhibiting greater efficacy than the existing drugs, against I. multifiliis trophonts in situ. We also verified the proteomic results by RT‐qPCR, TEM and cell apoptosis assay. Our results showed that major variations in protein abundance were found among many of the ribosome proteins, indicating ribosome might be a candidate target. Furthermore, GO and KEGG pathway analyses of differentially expressed proteins (DEPs) revealed that ribosome and PI3K‐Akt signalling pathway were remarkably enriched. Taken together, the above DEPs were also verified by RT‐qPCR and morphological observations. This study provides insights into the key proteins enriched in PI3K‐Akt signal pathway and ribosome pathway as potential targets of MG killing I. multifiliis, which could be served as targets for other less toxic drugs and be tested as potential treatments for I. multifiliis. [ABSTRACT FROM AUTHOR]

Sharpbelly Hemiculter leucisculus (Basilewski, 1855) is a small, widespread, and native cyprinid fish with prominent habitat suitability and high invasive potential and is becoming the dominant species in freshwater ecosystems under intensified environmental disturbances. But how H. leucisculus acclimates to extremely heterogeneous environments remains unclear. In current study, the genetic structure of H. leucisculus was analyzed using Bayesian phylogenetic inference, haplotype network, and STRUCTURE base on cytb gene across 18 populations spanning 20 degrees of latitude and 18 degrees of longitude in China. The morphological diversification of body size and shape for H. leucisculus along the climate gradient was studied. The results showed that the 18 H. leucisculus populations were divided into 3 clusters: one cluster mainly from Huanghe River Basin, another cluster mainly from Yangzi River Basin, and H cluster containing Hainan and Beihai populations. The fish from southern populations were deeper bodied while individuals from northern populations were more slender. Inland individuals were more streamlined while coastal individuals were of deeper body. The partial Mantel test predicts that the potential mechanism underlining the intraspecies morphological diversification along climate gradients is primarily the divergent selection pressures among different environments, while genetic variation had less contribution to morphological differentiation. The formation of the Nanling Mountain Range could drive genetic differentiation between Beihai population and those from Yangzi River Basin. The present results highlight strong selective pressures of climate on widespread species and enrich morphological differentiation basis of acclimation for species with high habitat suitability and invasive potential. [ABSTRACT FROM AUTHOR]

The fluorite structured actinide dioxides (AnO2), especially UO2, are the most common nuclear fuel materials. A comprehensive understanding of their surface chemistry is critical because of its relevance to the safe handling, usage, and storage of nuclear fuels. Because of the ubiquitous nature of water (H2O), its interaction with AnO2 has attracted significant attention for its significance in studies of nuclear fuels corrosion and the long-term storage of nuclear wastes. The last few years have seen extensive experimental and theoretical studies on the H2O–AnO2 interaction. Herein, we present a brief review of recent advances in this area. We focus on the atomic structures of AnO2 surfaces, the surface energies, surface oxygen vacancies, their influence on the oxidation states of actinide atoms, and the adsorption and reactions of H2O on stoichiometric and reduced AnO2 surfaces. Finally, a summary and outlook of future studies on surface chemistry of AnO2 are given. We intend for this review to encourage broader interests and further studies on AnO2 surfaces. [ABSTRACT FROM AUTHOR]

Bialkali photocathodes, such as cesium potassium antimonide (CsK2Sb), can generate a high-brightness electron beam using a high-power green laser. These photocathode materials have potential applications in advanced accelerators and electron microscopes. It is known that the quantum efficiency (QE) of these photocathodes is affected severely by their substrates; however, reusability of the substrates is not well known. Here, we use graphene, silicon (Si), and molybdenum (Mo) substrates to evaluate the effects of substrates on the QE of redeposited CsK2Sb photocathodes after thermal cleanings. We found that the QE of CsK2Sb photocathodes redeposited on a graphene substrate after thermal cleaning at 500 °C remained largely unchanged. On the other hand, the QE of redeposited photocathodes on Si and Mo substrates after thermal cleaning at the same temperature decreased drastically. We used x-ray photoelectron spectroscopy to quantitatively evaluate the residues of photocathodes after thermal cleaning at 400 °C and 500 °C. We found that Sb, K, and Cs are removed by thermal cleaning at 500 °C for the graphene substrate, but all or the majority of these elements remained on the Si and Mo substrates. The results were consistent with our density functional theory calculations for the case of Si, which we investigated. Furthermore, our angle-resolved photoemission spectroscopy on graphene indicated that its intrinsic electronic structure is preserved after photocathode deposition and thermal cleaning at 500 °C. Hence, we attributed the difference in the amount of photocathode residue to the unique dangling-bond-free surface of inert graphene. Our results provide a foundation for graphene-based reusable substrates for high-QE semiconductor photocathodes. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (GNPs) are one of the most widely used nanomaterials in various fields. Especially, the unique chemical and physical properties make them as the promising candidates in drug target identification, unfortunately, little is known about their application in parasites. In this paper, GNPs were employed as new solid support to identify drug targets of natural bioactive compound arctigenin (ARG) against fish monogenean parasite Gyrodactylus kobayashi. Before target identification, GNPs with ARG on the surface showed the ability to enter the live parasites even the nucleus or mitochondria, which made the bound compounds capable of contacting directly with target proteins located anywhere of the parasites. At the same time, chemically modified compound remained the anthelminthic efficacy against G. kobayashii. The above results both provide assurance on the reliability of using GNPs for drug target-binding specificity. Subsequently, by interrogating the cellular proteome in parasite lysate, myosin-2 and UNC-89 were identified as the potential direct target proteins of ARG in G. kobayashii. Moreover, results of RNA-seq transcriptomics and iTRAQ proteomics indicated that myosin-2 expressions were down-regulated after ARG bath treatment both in transcript and protein levels, but for UNC-89, only in mRNA level. Myosin-2 is an important structural muscle protein expressed in helminth tegument and its identification as our target will enable further inhibitor optimization towards future drug discovery. Furthermore, our findings demonstrate the power of GNPs to be readily applied to other parasite drugs of unknown targets, facilitating more broadly therapeutic drug design in any pathogen or disease model. [ABSTRACT FROM AUTHOR]

CoZr columnar structured magnetic films were fabricated by oblique sputtering onto porous aluminum oxide substrates with different oblique angles. The scanning electron microscope images showed the formation of columnar structure and nanoporous structure was disappeared with increasing oblique angle. The static magnetic properties showed larger coercivity and lower magnetization squareness due to columnar structure resulted from nanopores. Dynamic magnetic properties were determined by effect of holes and oblique sputtering. Enhanced microwave absorption was obtained by complex permeability measurement, which line width of columnar film increased 1.4 GHz comparing with 0.5 GHz of continuous film. Therefore, it is an effective way to get the adjustable anisotropy field and line width, which is desirable for obtaining the high resonance and high permeability ferromagnetic film materials for high frequency application. [ABSTRACT FROM AUTHOR]

The subheading "Photoemission measurement", now reads: "Spectral response photoemission measurements." Finally, in the Methods, under the subheading 'Sandwiching bialkali antimonide photocathodes between graphene and nickel thin films', "Graphene consisting of mainly monolayer regions with some multiple layer regions was synthesized via chemical vapor deposition (CVD) SP 43 sp on Cu substrates and transferred onto TEM mesh grids using an established polymer-supported method that involves distilled water exposure SP 44 sp . [Extracted from the article]

The applicability of graphene in nanoscale devices is somewhat limited because of the absence of a finite band gap. To overcome this limitation of zero band gap, we consider vertically-stacked heterostructures consisting of graphene and SnO knowing that two-dimensional SnO films were synthesized recently. Calculations based on density functional theory find that the oxide monolayer can induce a notable band gap in graphene; 115 meV in SnO/graphene/SnO heterostructures. Additionally, the band gap of graphene can be maintained under a relatively high electric field (≈109 V m−1) applied to the heterostructures because of the electrostatic screening effect of the oxide layer. The calculated results suggest the relative superiority of the graphene/oxide heterostructures over graphene/BN heterostructures for the nanoscale devices based on graphene. [ABSTRACT FROM AUTHOR]

Nanocrystals (NCs) with size and shape dependent properties are a thriving research field. Remarkable progress has been made in the controlled synthesis of NCs of stable elements in the past two decades; however, the knowledge of the NCs of actinide compounds has been considerably limited due the difficulties in handling them both experimentally and theoretically. Actinide compounds, especially actinide oxides, play a critical role in many stages of the nuclear fuel cycle. Recently, a non-aqueous surfactant assisted approach has been developed for the synthesis of actinide oxide NCs with different morphologies, but an understanding of its control factors is still missing to date. Herein we present a comprehensive study on the low index surfaces of thorium dioxide (ThO2) and their interactions with relevant surfactant ligands using density functional calculations. A systematic picture on the thermodynamic stability of ThO2 NCs of different sizes and shapes is obtained employing empirical models based on the calculated surface energies. It is found that bare ThO2 NCs prefer the octahedral shape terminated by (111) surfaces. Oleic acid displays selective adsorption on the (110) surface, leading to the shape transformation from octahedrons to nanorods. Other ligands such as acetylacetone, oleylamine, and trioctylphosphine oxide do not modify the equilibrium shape of ThO2 NCs. This work provides atomic level insights into the anisotropic growth of ThO2 NCs that was recently observed in experiments, and thus may contribute to the controlled synthesis of actinide oxide NCs with well-defined size and shape for future applications. [ABSTRACT FROM AUTHOR]

The discovery of graphene has inspired extensive interest in two-dimensional ( 2D) materials, and has led to synthesis/growth of additional 2D materials, generally referred to as 'Beyond Graphene'. Notable among the recently discovered exotic 2D materials are group IV elemental monolayers silicene and germanene, group V elemental monolayer phosphorene, and binary monolayers, such as hexagonal boron nitride ( h- BN), and molybdenum disulfide ( MoS2 ). Environmental effect on the physical and chemical properties of these 2D materials is a fundamental issue for their practical applications in devices operating under ambient conditions, especially, exposure to air often leads to oxidation of nanomaterials with significant impact on the functional properties and performances of devices built with them. In view of its importance, we present here a review of the recent experimental and theoretical studies on the oxidation of 2D materials focusing on the relationship between the oxidation process and the energy values which can be calculated by first principles methods. The complement of experiments and theory facilitates the understanding of the underlying oxidation process in terms of cohesive energy, energy barrier to oxidation and dissociation energy of oxygen molecule for 2D materials including graphene, silicene, germanene, phosphorene, h- BN, and MoS2. WIREs Comput Mol Sci 2017, 7:e1280. doi: 10.1002/wcms.1280 For further resources related to this article, please visit the . [ABSTRACT FROM AUTHOR]

Since the use of malachite green was banned, it is desirable to search for alternative drug to control Ichthyophthirius multifiliis infection. Moreover, route of administration which is easy to implement and less stressful to fish is important to treat infection of fish with this parasite. It is also important to enhance protective effect against Aeromonas hydrophila infection after parasitism by I. multifiliis. The present study evaluated the protective effect of diet supplemented with Artemisia annua against I. multifiliis and A. hydrophila infection after the parasitism. The results showed that oral administration with A. annua at a concentration of 20 g/kg feed for 45 days can provide strong protection against I. multifiliis infection. The incidence of infestation and mean number of trophonts on fish fins on day 3 post-challenge (15,000 theronts/fish) were significantly reduced compared with the control, and the survival rate of fish during 15-day period was also increased by nearly 30 %. But, this diet provided very limited protection against higher infection dose. Besides, this study demonstrated that this diet enhanced protective effect against A. hydrophila after the fish were infected with I. multifiliis. On the basis of the above results, oral administration with A. annua can be used as a potential strategy for control I. multifiliis infection and increasing fish survival after parasitism by I. multifiliis. [ABSTRACT FROM AUTHOR]

Goldfish is known to be parasitized by at least seven species of Dactylogyrus and considered as one of the most common hosts. Dactylogyrus vastator and Dactylogyrus intermedius are the dominant species living on the gills of goldfish. However, little information on morphometric characterization is available, which easily causes misidentification. The purpose of this study is to provide comprehensive morphometric and molecular characterization of D. vastator and D. intermedius collected form a fish farm in Henan, China. The characterization was presented based on the high-resolution images and standard molecular markers (18S ribosomal DNA subunit and the internal transcribed spacer region), as well as a total of 10 point-to-point morphometrics characters. In addition, a detailed comparison of morphometric and phylogenetic characterization in D. vastator versus D. intermedius was performed. The results demonstrated that all parameters measured differed significantly between these two species of Dactylogyrus, whereas molecular comparison showed subtle differences between them in nucleotide divergence and genetic distances. These findings suggested that these two species of Dactylogyrus can be distinguished more easily based on morphometric measurements than molecular data for 18S ribosomal DNA + internal transcribed spacer region (ITS-1). [ABSTRACT FROM AUTHOR]

Dactylogyrus formosus Kulwiec, 1927 (Monogenea: Dactylogyridae), widely distributed across Eurasia, is considered as one of the most frequently encountered ectoparasites of goldfish ( Carassius auratus). In the present study, D. formosus on gills of cultured goldfish was reported in central China for the first time, using the methods of morphological characters and molecular markers. It was characterized by 'Anchoratoid-Wegeneri' type anchor with elongate inner and unobvious outer root. The morphology of the opisthaptoral hard parts of D. formosus superficially resembles species of D. arcuatus Yamaguti, 1942 parasitized crucian carp, using light and scanning electron microscopy. However, the anchor total length of D. arcuatus (range 90-102) is almost double the size of D. formosus (range 43.7-57.1) which allows for their rapid discrimination from each other; on the other hand, the two species also can be easily separated by the shape of the male copulatory organ. The morphological description of D. formosus is supplemented with phylogenetic analysis of a reference DNA sequence spanning 18S rDNA and ITS1. What is more, this study also redescribes comprehensively D. formosus, providing for the first time a full ten point-to-point morphometric measurements of the hard parts, and importantly, a photographic record of the armature of the haptor and the male copulatory organ. [ABSTRACT FROM AUTHOR]

Goldfish, Carassius auratus, widely distributed across Eurasia, is one of the earliest fish domesticated for ornamental purposes. A series of diseases break out due to high-density culture of goldfish, causing significant economic losses. Here, we report for the first time an infection of Gyrodactylus kobayashii associated with the high mortality of goldfish from a fish farm in Anziying township of Henan province, China, following their transfer to several aquariums. In the first 2 weeks after goldfish ( n = 4200, weight 10.24 ± 1.45 g) transfer to aquariums, a total of 3335 goldfish were lost, representing 79.4 % of the initial stocked biomass. The examination showed that no other pathogens were found in this batch of fishes, except for G. kobayashii. The high burdens of G. kobayashii/fish (264.7, range 100-450) were the primary reason for the high mortality, although this was not the sole cause. In addition, the isolate of G. kobayashii from goldfish ( C. auratus) in Henan province of central China was described. The morphological characterization was performed using morphometric measurements and drawings of opisthaptoral hard parts of the parasites. The molecular description was performed based on phylogenetic analysis of a reference DNA sequence spanning 5.8S and ITS-2. Importantly, the present study provides for the first time a full 25 point-to-point morphometric measurements and high-resolution images of attachment organ of G. kobayashii. [ABSTRACT FROM AUTHOR]

Stripe domain (SD) structures of FeNi films were controlled by doping different concentrations of ferrite. With increasing concentration of doped ferrite, SD width decreases, which indicated that perpendicular magnetic anisotropy (H⊥) increases. SD disappears and bubble-like features are observed with doping ferrite at 32% due to large H⊥. The origin for the enhancement of H⊥ is exchange coupling between ferrimagnet and ferromagnet. Moreover, different doping concentrations of ferrite realize an increase of resonant frequency from 1.3 to 2.3 GHz. [ABSTRACT FROM AUTHOR]

Dactylogyrus spp. and Gyrodactylus spp. are helminth ectoparasites that are a significant threat to the aquaculture industry. Existing treatments could cause the threats of anthelmintic resistance, risk of residues, environmental contamination, and toxicity to fish. Importantly, there is no report on a treatment against these two parasites. This study explored the possibility of using the extracts of Santalum album to treat Dactylogyrus sp. and Gyrodactylus sp. infections in goldfish. Results showed that among the four extracts (chloroform, methanol, ethyl acetate, and water) of S. album, the chloroform extract is the most effective and 40 mg/L is a safe and the lowest effective dosage. In addition, we found that Gyrodactylus elegans is more sensitive than Dactylogyrus intermedius when exposed to the extract of the medicinal plant. Finally, it is substantiated that bath treatment with long duration and multiple administrations could eliminate a greater proportion of monogenean infections. These findings show the potential for the development of effective and safe therapy to treat Dactylogyrus sp. and Gyrodactylus sp. infections of fishes. [ABSTRACT FROM AUTHOR]

Ichthyophthirius multifiliis (also called 'ich') is an external protozoan parasite that may infest almost all freshwater fish species and caused significant economic damage to the aquaculture industry. Since the use of malachite green was banned, there have been relatively few effective alternative strategies for controlling I. multifiliis infections. The present study was designed to screen potential antiparasitic medicinal plants based on our previous studies, and comprehensively evaluate in vitro and in vivo anti-ich activity of selected plant extracts. The screening results showed that the methanol extract of Psoralea corylifolia had the highest activity against I. multifiliis theronts. In vivo theront trials demonstrated that 1.25 mg/L or more concentrations of P. corylifolia methanol extract caused 100 % mortality during the 4-h exposure period, and the subsequent in vitro trials indicated that the minimum concentration of P. corylifolia methanol extract that prevented the initial infestation was 2.50 mg/L. Protomonts and encysted tomonts surviving trials suggested that encysted tomonts were less susceptible to P. corylifolia methanol extract than protomonts, and the methanol extract of P. corylifolia at a concentration of 5.00 mg/L could kill 100 % of protomonts and 88.89 % of encysted tomonts. It was also observed that after 12-h exposure of protomonts or encysted tomonts to 2.50 mg/L of P. corylifolia methanol extract, the theronts emerged from encysted tomonts led to more infection level than the ones in the other groups. The results suggested that whether the protomonts finish encystment is crucial to the survival, reproduction, and theronts infectivity. In addition, our results showed that long duration (24 h) and high concentration (5.00 mg/L) significantly reduced the survival and reproduction of I. multifiliis tomont exited from the fish after in-bath treatment, and it is indicated that P. corylifolia methanol extract had a potential detrimental effect on I. multifiliis trophont in situ. [ABSTRACT FROM AUTHOR]

Manganese ferrite particles with spinel structure were synthesized by a modified co-precipitation method, and then the thermal stability on their structural and magnetic properties was investigated by thermal annealing at different gas ambients. Experimental results showed that decomposition of metal oxides occurred when Mn ferrite particles with spinel structure were annealed under air ambient, while samples annealed in vacuum or argon remained in the spinel structural form. The highest saturation magnetization value of 58 emu/g was obtained when the sample was annealed at 400°C in argon. The result showed that the thermal stability of MnFeO was better under Ar ambient conditions or in vacuum. [ABSTRACT FROM AUTHOR]

The FeCoZr/Cu multilayers were prepared by radio frequency sputtering. The static and microwave properties of these films were investigated by measuring the hysteresis loops and microwave permeability spectra. According to the static magnetic results, the multilayers were well in-plane uniaxial anisotropic samples with high saturation magnetization 1.7 T. The anisotropic field of these multilayer thin films can be adjusted from 18 Oe to 64 Oe by changing the thickness of Cu interlayer from 8.7 nm to 1.8 nm. As a consequence, the microwave permeability and resonance frequency can also be adjusted from 1.70 GHz to 2.88 GHz. This work might facilitate search for new materials with high permeability at high frequency. [ABSTRACT FROM AUTHOR]

Stripe domain (SD) in obliquely sputtered permalloy films were investigated by comparing with normally sputtered ones. The critical thickness for SD formation of obliquely sputtered films was about 100 nm thinner than that of normally sputtered films. The hysteresis loops of obliquely sputtered films showed a peculiar shape. A rotation of SD towards easy axis was observed in the obliquely sputtered films, which was confirmed by permeability spectra under a bias field. The origin of the rotation could result from in-plane uniaxial anisotropy, which is induced by the shape effect of the oblique columnar growth of permalloy grains. [ABSTRACT FROM AUTHOR]