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Summary: The influenza A virus nuclear export protein (NEP) is a multifunctional protein that is essential for the viral life cycle and has very high sequence conservation. However, since the open reading frame of NEP largely overlaps with that of another influenza viral protein, non-structural protein 1, it is difficult to infer the functional constraints of NEP based on sequence conservation analysis. In addition, the N-terminal of NEP is structurally disordered, which further complicates the understanding of its function. Here, we systematically measure the replication fitness effects of >1,800 mutations of NEP. Our results show that the N-terminal domain has high mutational tolerance. Additional experiments show that N-terminal domain mutations affect viral transcription and replication dynamics, host cellular responses, and mammalian adaptation of avian influenza virus. Overall, our study not only advances the functional understanding of NEP but also provides insights into its evolutionary constraints.

Abstract Background Network modeling has been proposed as an effective approach to examine complex associations among antecedents, mediators and symptoms. This study aimed to investigate whether the severity of depressive symptoms affects the multivariate relationships among symptoms and mediating factors over a 2-year longitudinal follow-up. Methods We recruited a school-based cohort of 1480 primary and secondary school students over four semesters from January 2020 to December 2021. The participants (n = 1145) were assessed at four time points (ages 10–13 years old at baseline). Based on a cut-off score of 5 on the 9-item Patient Health Questionnaire at each time point, the participants were categorized into the non-depressive symptom (NDS) and depressive symptom (DS) groups. We conducted network analysis to investigate the symptom-to-symptom influences in these two groups over time. Results The global network metrics did not differ statistically between the NDS and DS groups at four time points. However, network connection strength varied with symptom severity. The edge weights between learning anxiety and social anxiety were prominently in the NDS group over time. The central factors for NDS and DS were oversensitivity and impulsivity (3 out of 4 time points), respectively. Moreover, both node strength and closeness were stable over time in both groups. Conclusions Our study suggests that interrelationships among symptoms and contributing factors are generally stable in adolescents, but a higher severity of depressive symptoms may lead to increased stability in these relationships.

With the continuous development of modern UAV technology and communication technology, UAV-to-ground communication relay has become a research hotspot. In this paper, a Multi-Agent Reinforcement Learning (MARL) method based on the ε-greedy strategy and multi-agent proximal policy optimization (MAPPO) algorithm is proposed to address the local optimization problem, improving the communication efficiency and task execution capability of UAV cluster control. This paper explores the path planning problem in multi-UAV-to-ground relay communication, with a special focus on the application of the proposed Mix-Greedy MAPPO algorithm. The state space, action space, communication model, training environment, and reward function are designed by comprehensively considering the actual tasks and entity characteristics such as safe distance, no-fly zones, survival in a threatened environment, and energy consumption. The results show that the Mix-Greedy MAPPO algorithm significantly improves communication probability, reduces energy consumption, avoids no-fly zones, and facilitates exploration compared to other algorithms in the multi-UAV ground communication relay path planning task. After training with the same number of steps, the Mix-Greedy MAPPO algorithm has an average reward score that is 45.9% higher than the MAPPO algorithm and several times higher than the multi-agent soft actor-critic (MASAC) and multi-agent deep deterministic policy gradient (MADDPG) algorithms. The experimental results verify the superiority and adaptability of the algorithm in complex environments.

As a full tension structural system, the spoke-type single-layer cable net structure has a light graceful shape and superior mechanical properties. During construction, the structure will gradually be tensioned from the flexible unstressed state to the formed state with stiffness, and the structural configuration changes greatly, making construction difficult. This study focused on the spoke-type single-layer cable net structure of the Linyi Olympic Sports Center Stadium. The structural finite element model was established in ANSYS, and the construction scheme was selected and simulated using the nonlinear dynamic finite element method (NDFEM). Most of the existing structural automatic measuring systems are suitable for measuring points with gentle deformation. However, there is the lack of a stable and reliable automatic configuration monitoring system for the construction of single-layer cable net structures. Based on the Lecia TS16 robotic total station (RTS), the configuration automatic monitoring system (CAMS) was developed to obtain the coordinate data of key nodes on the ring cable and compression ring during the construction process. The original finite element model of clamps was refined to obtain the corresponding data in ANSYS. The results indicate that the selected construction scheme has a rational mechanical response according to the finite element simulation. The radial cable force when anchoring the traction cables is smaller than or equal to that in the formed state, which proves that the construction method of anchoring in batches is safe. The results of the ANSYS simulation is basically consistent with those obtained by CAMS, proving that the simulation method is credible. CAMS has good stability and measurement accuracy and can achieve the automatic monitoring of large structural deformation. The research findings provide valuable guidance for practical construction and other similar projects.

Along with urbanization and industrialization, carbon emissions have been increasing significantly, resulting in global warming. Green space has been widely accepted as a natural element in cities to directly increase carbon sinks and indirectly reduce carbon emissions. The quantification of carbon benefits generated by green space is an important topic. This paper aims to provide a comprehensive review of the methods for measuring carbon sinks of green spaces. The results indicate that existing assessment methods can accurately estimate the carbon sinks in green spaces at large scales. However, existing methods are not fully applicable to studies of urban green spaces, due to the low precision of research results. The assimilation method is the most suitable method to study the carbon sequestration efficiency of plants and can project the carbon sinks of urban green spaces at large scales through macroscopic means. Even though, the results of assimilation experiments are unstable under different weather conditions. To address existing research challenges, this paper proposes a photosynthetic rate estimation method based on the light-response curve which is an efficient method to describe the relationship between light intensity and net photosynthetic rate in studying plant physiological characteristics. The newly proposed method, through integrating net photosynthesis-light response curves and urban light intensity associated with meteorological data, has advantages of short measurement time and ensuring standardized experimental environment for result comparability. Overall, this study is important to combine meteorology and plant physiology to propose a photosynthetic rate estimation method for optimizing carbon sink measurement in urban green spaces. The method is more convenient for application for its simple experimental process and result comparability. In practice, this study provides guidance for low-carbon urban green space planning and design, and helps to promote energy conservation and emission reduction through nature-based solutions.

A central goal of evolutionary developmental biology is to decipher the evolutionary pattern of gene regulatory networks (GRNs) that control embryonic development, and the mechanism underlying GRNs evolution. The Nodal signaling that governs the body axes of deuterostomes exhibits a conserved GRN orchestrated principally by Nodal, Gdf1/3, and Lefty. Here we show that this GRN has been rewired in cephalochordate amphioxus. We found that while the amphioxus Gdf1/3 ortholog exhibited nearly no embryonic expression, its duplicate Gdf1/3-like, linked to Lefty, was zygotically expressed in a similar pattern as Lefty. Consistent with this, while Gdf1/3-like mutants showed defects in axial development, Gdf1/3 mutants did not. Further transgenic analyses showed that the intergenic region between Gdf1/3-like and Lefty could drive reporter gene expression as that of the two genes. These results indicated that Gdf1/3-like has taken over the axial development role of Gdf1/3 in amphioxus, possibly through hijacking Lefty enhancers. We finally demonstrated that, to compensate for the loss of maternal Gdf1/3 expression, Nodal has become an indispensable maternal factor in amphioxus and its maternal mutants caused axial defects as Gdf1/3-like mutants. We therefore demonstrated a case that the evolution of GRNs could be triggered by enhancer hijacking events. This pivotal event has allowed the emergence of a new GRN in extant amphioxus, presumably through a stepwise process. In addition, the co-expression of Gdf1/3-like and Lefty achieved by a shared regulatory region may have provided robustness during body axis formation, which provides a selection-based hypothesis for the phenomena called developmental system drift.

ABSTRACTBetacoronaviruses encode an internal (I) gene via an alternative reading frame within the nucleocapsid gene, called ORF8b for Middle-East respiratory syndrome coronavirus (MERS-CoV) and ORF9b for severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2. Previous reports suggested that proteins 8b and 9b are involved in evading multiple innate immune signaling pathways. However, their roles in mediating pathogenesis in infected animals have not been determined. In this study, we abrogated the expression of protein 8b in MERS-CoV and protein 9b in SARS-CoV-2. Using mouse models of MERS-CoV and SARS-CoV-2 infection, we found that MERS-CoV lacking protein 8b expression was more virulent, while SARS-CoV-2 lacking protein 9b expression was attenuated compared with the respective wild-type viruses. Upon further analysis, we detected increased levels of type I interferon and enhanced infiltration of immune cells to the lungs of mice infected with MERS-CoV lacking protein 8b expression. These data suggest that the I protein of MERS-CoV plays a role in limiting pathogenesis while that of SARS-CoV-2 enhances disease severity.IMPORTANCEThe function of betacoronavirus internal protein has been relatively understudied. The earliest report on the internal protein of mouse hepatitis virus suggested that the internal protein is a structural protein without significant functions in virus replication and virulence. However, the internal proteins of severe acute respiratory syndrome coronavirus (SARS-CoV), Middle-East respiratory syndrome coronavirus, and SARS-CoV-2 have been shown to evade immune responses. Despite the reported functions of the internal protein in these highly pathogenic human coronaviruses, its role in mediating pathogenesis in experimentally infected animals has not been characterized. Our data indicated that despite the similar genomic location and expression strategy of these internal proteins, their effects on virulence are vastly different and virus specific, highlighting the complexity between host-virus interaction and disease outcome.

Summary: IGHV1-69 is frequently utilized by broadly neutralizing influenza antibodies to the hemagglutinin (HA) stem. These IGHV1-69 HA stem antibodies have diverse complementarity-determining region (CDR) H3 sequences. Besides, their light chains have minimal to no contact with the epitope. Consequently, sequence determinants that confer IGHV1-69 antibodies with HA stem specificity remain largely elusive. Using high-throughput experiments, this study reveals the importance of light-chain sequence for the IGHV1-69 HA stem antibody CR9114, which is the broadest influenza antibody known to date. Moreover, we demonstrate that the CDR H3 sequences from many other IGHV1-69 antibodies, including those to the HA stem, are incompatible with CR9114. Along with mutagenesis and structural analysis, our results indicate that light-chain and CDR H3 sequences coordinately determine the HA stem specificity of IGHV1-69 antibodies. Overall, this work provides molecular insights into broadly neutralizing antibody responses to influenza virus, which have important implications for universal influenza vaccine development.

Lei et al. systematically characterized the epistasis among natural mutations in the neuraminidase of human influenza H3N2 virus, which provide insights into the biophysical constraints that shaped its evolution trajectory over the past half-century.

Agricultural production in the Weibei rainfed highland, Northwest China, is challenged by severe drought and water shortages. While the land use pattern has shifted gradually from crop production to orchard farming in Weibei, little is known about the influence of fruit industry development on regional water resources and the rationality of planting orchards. Here, we characterized soil water depletion patterns in rainfed orchards and farmlands to evaluate the occurrence of soil desiccation under land use conversion from farmlands to orchards in Weibei. Soil moisture dynamics were monitored in the 0–150 cm soil profiles of different aged Red Fuji apple orchards (young: 7 years, mature: 13 years, old: 22 years) and long-term cultivated winter wheat fields. We measured soil moisture content by oven-drying method in the middle of each month during the growing season of apple trees (March–September 2019). The over-depletion and depletion of soil water were analyzed to evaluate water stress and differential water depletion by distinct vegetation, respectively. The soil desiccation index was used to determine the occurrence of dry soil layers. Water stress was only observed at the 0–70-cm soil depths in the old orchards (mid-June) and farmlands (mid-May–mid-July). Water depletion took place at deeper depths for longer periods in the older orchards than in the younger orchards. Soil desiccation was absent in the young orchards, with mild desiccation at the 0–80-cm soil depths in the mature and old orchards in mid-June. The desiccation intensity was mild at the 0–60-cm soil depths in mid-April–mid-May, intense at the 0–150-cm soil depths in mid-June, and moderate at the 20–150-cm soil depths in mid-July. Results of this study demonstrate the mitigation of water stress and soil desiccation following conversion from wheat fields to apple orchards, which verifies the rationality of planting orchards in the rainfed highland area. Our findings provide strong support for developing a novel model of agro-industrial development, ecological construction, and sustainable economy in the vast arid and semi-arid areas of Northwest China.

The Local Climate Zone (LCZ), as a foundational element of urban climate zone classification proposed by Oke and Stewart, categorizes urban surface types based on 10 influential parameters affecting the urban heat island effect, such as building density, surface reflectivity, sky view factor, and surface roughness length. This method divides cities into 17 different Local Climate Zones (LCZs) to standardize climate observations and promote global climate research exchange, offering valuable insights for heat island studies. In this study, we enhance the existing local climate zones spatial classification approach by focusing on Xi’an city’s urban layout and architectural features. By using urban spatial indicators and employing a supervised classification approach and a spatial clustering method with land parcels as statistical units, we investigate typical urban areas and classify Xi’an’s land parcels into 17 or 15 distinct local climate zones. Subsequently, through the evaluation of two distinct classification methods, the most suitable urban microclimate zoning method for Xi’an city was selected. This optimization of the local climate zoning representation introduces a spatial classification method tailored to urban climate planning and control, utilizing urban spatial indicators and remote sensing data. The resulting urban climate zoning map not only supports sample selection for urban heat environment parameter observation but also aids urban planners in identifying spatial distribution patterns for climate zoning.

Abstract Introduction The left-sided position of the mouth in amphioxus larvae has fascinated researchers for a long time. Despite the fundamental importance of mouth development in the amphioxus, the molecular regulation of its development is almost unknown. In our previous study, we showed that Hh mutation in the amphioxus leads to no mouth opening, indicating a requirement of Hh signaling for amphioxus mouth formation. Nevertheless, since the Hh mutant also exhibits defects in early left-right (LR) patterning, it remains currently unknown whether the loss of mouth opening is affected directly by Hh deficiency or a secondary effect of its influence on LR establishment. Results We demonstrated that knockout of the Smo gene, another key component of the Hh signaling pathway, in the amphioxus resulted in the absence of mouth opening, but caused no effects on LR asymmetry development. Upregulation of Hh signaling led to a dramatic increase in mouth size. The inability of Smo mutation to affect LR development is due to Smo’s high maternal expression in amphioxus eggs and cleavage-stage embryos. In Smo mutants, Pou4 and Pax2/5/8 expression at the primordial oral site is not altered before mouth opening. Conclusions Based on these results and our previous study, we conclude that Hh signal is necessary for amphioxus mouth formation and that the Hh-mediated regulation of mouth development is specific to the mouth. Our data suggest that Hh signaling regulates mouth formation in the amphioxus in a similar way as that in vertebrates, indicating the conserved role of Hh signaling in mouth formation.

Abstract Background Left-right (LR) asymmetry is an essential feature of bilateral animals. Studies in vertebrates show that LR asymmetry formation comprises three major steps: symmetry breaking, asymmetric gene expression, and LR morphogenesis. Although much progress has been made in the first two events, mechanisms underlying asymmetric morphogenesis remain largely unknown due to the complex developmental processes deployed by vertebrate organs. Results We here addressed this question by studying Pitx gene function in the basal chordate amphioxus whose asymmetric organogenesis, unlike that in vertebrates, occurs essentially in situ and does not rely on cell migration. Pitx null mutation in amphioxus causes loss of all left-sided organs and incomplete ectopic formation of all right-sided organs on the left side, whereas Pitx partial loss-of-function leads to milder phenotypes with only some LR organs lost or ectopically formed. At the N1 to N3 stages, Pitx expression is gradually expanded from the dorsal anterior domain to surrounding regions. This leads to activation of genes like Lhx3 and/or Prop1 and Pit, which are essential for left-side organs, and downregulation of genes like Hex and/or Nkx2.1 and FoxE4, which are required for right-side organs to form ectopically on the left side. In Pitx mutants, the left-side expressed genes are not activated, while the right-side genes fail to decrease expression on the left side. In contrast, in embryos overexpressing Pitx genes, the left-side genes are induced ectopically on the right side, and the right-side genes are inhibited. Several Pitx binding sites are identified in the upstream sequences of the left-side and right-side genes which are essential for activation of the former and repression of the latter by Pitx. Conclusions Our results demonstrate that (1) Pitx is a major (although not the only) determinant of asymmetric morphogenesis in amphioxus, (2) the development of different LR organs have distinct requirements for Pitx activity, and (3) Pitx controls amphioxus LR morphogenesis probably through inducing left-side organs and inhibiting right-side organs directly. These findings show much more dependence of LR organogenesis on Pitx in amphioxus than in vertebrates. They also provide insight into the molecular developmental mechanism of some vertebrate LR organs like the lungs and atria, since they show a right-isomerism phenotype in Pitx2 knockout mice like right-sided organs in Pitx mutant amphioxus. Our results also explain why some organs like the adenohypophysis are asymmetrically located in amphioxus but symmetrically positioned in vertebrates.

Public antibody clonotypes that recognize SARS-CoV-2 spike protein are important for protection against COVID-19. Here, the authors characterize sequence motifs in the heavy chain complementarity-determining region (CDR) H3s of two public clonotypes and their association with light chain identity.

Abstract Energy storage system can be used to increase the fuel economy of fuel cell system (FCS). In this study, a new method was introduced for optimizing the energy management strategy (EMS) for fuel cell vehicle (FCV) to reduce fuel consumption. The membership function (MF) in fuzzy control is subjective; thus, 12 design variables in the input‐output MFs were selected using sensitivity analysis, and elliptical basis function neural network method was used to establish a high‐precision approximate model of FCV. Multi‐island genetic algorithm was used to optimize the MFs. The effectiveness of the optimized fuzzy control EMS and the proposed optimization method were demonstrated in simulations of two EMSs under four driving cycles. The simulation results confirmed that the optimized fuzzy control EMS provided smoother and more stable output power from FCS reducing hydrogen consumption by 8.4%, 1.1%, 5.1%, and 7.6%, respectively, compared to the original fuzzy control EMS; and hydrogen saved by the optimized EMS provided extra range of 9.15, 1.10, 5.37, and 8.25 km per 100 km in the four driving cycles, respectively. The optimized EMS can reduce hydrogen consumption to increase fuel economy and extend the life span of the fuel cell.

Egg-adaptive mutations in influenza hemagglutinin (HA) often emerge during the production of egg-based seasonal influenza vaccines, which contribute to the largest share in the global influenza vaccine market. While some egg-adaptive mutations have minimal impact on the HA antigenicity (e.g. G186V), others can alter it (e.g. L194P). Here, we show that the preference of egg-adaptive mutation in human H3N2 HA is strain-dependent. In particular, Thr160 and Asn190, which are found in many recent H3N2 strains, restrict the emergence of L194P but not G186V. Our results further suggest that natural amino acid variants at other HA residues also play a role in determining the preference of egg-adaptive mutation. Consistently, recent human H3N2 strains from different clades acquire different mutations during egg passaging. Overall, these results demonstrate that natural mutations in human H3N2 HA can influence the preference of egg-adaptation mutation, which has important implications in seed strain selection for egg-based influenza vaccine.

As one of the main influenza antigens, neuraminidase (NA) in H3N2 virus has evolved extensively for more than 50 years due to continuous immune pressure. While NA has recently emerged as an effective vaccine target, biophysical constraints on the antigenic evolution of NA remain largely elusive. Here, we apply combinatorial mutagenesis and next-generation sequencing to characterize the local fitness landscape in an antigenic region of NA in six different human H3N2 strains that were isolated around 10 years apart. The local fitness landscape correlates well among strains and the pairwise epistasis is highly conserved. Our analysis further demonstrates that local net charge governs the pairwise epistasis in this antigenic region. In addition, we show that residue coevolution in this antigenic region is correlated with the pairwise epistasis between charge states. Overall, this study demonstrates the importance of quantifying epistasis and the underlying biophysical constraint for building a model of influenza evolution.

Fuel cell vehicles (FCVs) are becoming increasingly popular because they are both environmentally friendly and energy efficient. However, because no waste heat from the internal combustion engine can be used, the additional electricity needed to heat the cabin in cold weather increases the energy consumption substantially. This also lowers both the fuel economics and driving range. The required additional heating is typically done with a positive temperature coefficient (PTC) electric heater. To overcome the associated performance problem, a novel vehicle-integrated thermal management system (VTMS) with a heat-pump system is developed and investigated in this study. Using a simulation, the performance of the VTMS is investigated with respect to cooling performance, heating performance, and heating energy consumption for several different heat sources. For four different driving cycles, the equivalent hydrogen consumption (EHC) is highest when the PTC heater is used. The heat-pump system, which uses waste heat generated by a proton exchange membrane fuel cell, shows the lowest EHC. The results reveal that the use of a heat-pump heating system with waste heat can reduce hydrogen consumption by ∼14.6%, 6.5%, 16.9%, and 16.7% compared to PTC heating. Furthermore, the driving ranges increased by 17.2, 6.8, 20.3, and 12.6 km per 100 km, respectively. The VTMS, thanks to its ability to reduce energy consumption effectively, makes it possible to improve the thermal comfort in the vehicle cabin, which is especially useful for the commercialization of FCVs.

Virus propagation methods generally use transformed cell lines to grow viruses from clinical specimens, which may force viruses to rapidly adapt to cell culture conditions, a process facilitated by high viral mutation rates. Upon propagation in VeroE6 cells, SARS-CoV-2 may mutate or delete the multibasic cleavage site (MBCS) in the spike protein. Previously, we showed that the MBCS facilitates serine protease-mediated entry into human airway cells (Mykytyn et al., 2021). Here, we report that propagating SARS-CoV-2 on the human airway cell line Calu-3 – that expresses serine proteases – prevents cell culture adaptations in the MBCS and directly adjacent to the MBCS (S686G). Similar results were obtained using a human airway organoid-based culture system for SARS-CoV-2 propagation. Thus, in-depth knowledge on the biology of a virus can be used to establish methods to prevent cell culture adaptation.

A novel all-pass slot microring resonator (SMRR), intended for label-free optical biosensing based on silicon-on-insulator platforms, is proposed. The sensor consists of a bent asymmetric directional coupler and an asymmetric-slot microring waveguide. The appropriate slot width of 140 nm is identified by the three-dimensional finite-difference time-domain (3D-FDTD) method for better light–matter interaction in applications. According to numerical calculations, the SMRR sensor with a footprint of 10 µm × 10 µm has a concentration sensitivity of 725.71 pm/% for sodium chloride (NaCl) solutions. The corresponding refractive index sensitivity is 403 nm/RIU (refractive index unit), which is approximately six times greater than that of traditional microring resonator sensors. A low detection limit of 0.129% is also achieved. This SMRR is an excellent candidate for label-free optical biosensors due to its compact structure and excellent sensing capability.

Summary: The World Health Organization has declared the ongoing outbreak of COVID-19, which is caused by a novel coronavirus SARS-CoV-2, a pandemic. There is currently a lack of knowledge about the antibody response elicited from SARS-CoV-2 infection. One major immunological question concerns antigenic differences between SARS-CoV-2 and SARS-CoV. We address this question by analyzing plasma from patients infected by SARS-CoV-2 or SARS-CoV and from infected or immunized mice. Our results show that, although cross-reactivity in antibody binding to the spike protein is common, cross-neutralization of the live viruses may be rare, indicating the presence of a non-neutralizing antibody response to conserved epitopes in the spike. Whether such low or non-neutralizing antibody response leads to antibody-dependent disease enhancement needs to be addressed in the future. Overall, this study not only addresses a fundamental question regarding antigenicity differences between SARS-CoV-2 and SARS-CoV but also has implications for immunogen design and vaccine development.

Based on the conjugated complex PVK: Ir(ppy)3, a green-emitting organic quasicrystal microcavity laser is demonstrated driven by optical pumping. The organic laser adopts a sandwich structure of DBR/organic gain membrane/output Ag-layer for the vertical oscillation and an octagonal quasi-crystal for in-plane light localization. The experimental results show that the single-mode lasing action is observed at 521 nm with an FWHM of 0.8 nm. The threshold of lasing is lowered to 0.181 μJ/cm2.

Background/Aims: Benzotriazole (BTR) and its derivatives, such as intermediates and UV stabilizers, are important man-made organic chemicals found in everyday life that have been recently identified as environmental toxins and a threat to female reproductive health. Previous studies have shown that BTR could act as a carcinogen by mimicking estrogen. Environmental estrogen mimics could promote the initiation and development of female cancers, such as endometrial carcinoma, a type of estrogenic-sensitive malignancy. However, there is little information on the relationship between BTR and endometrial carcinoma. In this study, we aimed to demonstrate the biological function of BTR in endometrial carcinoma and explored the underlying mechanism. Methods: The CCK-8 assay was performed to detect cell viability; transwell-filter assay was used to assess cell invasion; gene microarray analysis was employed to determine gene expression patterns in response to BTR treatment; western blotting and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were carried out to detect the expression levels of BTR-related genes. Results: Our data showed that BTR could induce the invasion and migration of endometrial carcinoma cells (Ishikawa and HEC-1-B). In addition, BTR increased the expression level of CTBP1, which could enhance the epithelial-mesenchymal transition (EMT) in cancer cells. Moreover, CTBP1 silencing reversed the effect of BTR on EMT progression in endometrial carcinoma cells. Conclusion: This study indicates that BTR could act as a carcinogen to promote the development of endometrial carcinoma mainly through CTBP1-mediated EMT, which deserves more attention.

Abstract Amphioxus or lancelets have been regarded as a key animal in understanding the origin of vertebrates. However, the evolutionary history within this lineage remains unexplored. As the amphioxus lineage has likely been separated from other chordates for a very long time and displays a marked left-right asymmetry, its evolutionary history is potentially helpful in better understanding chordate and vertebrate origins. We studied the phylogenetic relationships within the extant amphioxus lineage based on mitochondrial genomes incorporating new Asymmetron and Epigonichthys populations, and based on previously reported nuclear transcriptomes. The resulting tree patterns are consistent, showing the Asymmetron clade diverging first, followed by the Epigonichthys and Branchiostoma clades splitting. Divergence time estimates based on nuclear transcriptomes with vertebrate calibrations support a shallow diversification of the extant amphioxus lineage in the Tertiary. These estimates fit well with the closure of seaways between oceans by continental drift, ocean currents, and present geographical distributions, and suggest a long cryptic history from the origin of amphioxus to its most recent diversification. Deduced character polarities based on phylogenetic analyses suggest that the common ancestor of the extant amphioxus existed in a tiny epibenthic state with larva-like appearance of extant amphioxus, likely with ciliate epidermis.

Phosphorescent iridium complexes ranged from far-red to NIR have attracted great attention as oxygen probes or photosensitizers recently. In this work, a far-red phosphorescent iridium complex ((DPQ)2Ir(acac)) was adopted to prepare biocompatible nanoparticles (Ir-NPs) for both phosphorescence imaging and photodynamic therapy of living cells. The iridium complex was highly sensitive to oxygen in organic solvent, but became less insensitive after being incorporated into NPs, though the particle matrix was highly permeable to oxygen. Moreover, the Ir-NPs exhibited a fast rate of singlet oxygen generation under 660 nm light irradiation. Taking advantage of these Ir-NPs, cellular imaging in the far-red range was realized; meanwhile, in vitro PDT was successfully performed. These results suggested that the Ir-NPs can function as both bio-imaging agents and nano-photosensitizers that work in the far red range.

Wavelength-tunable thulium-doped fiber laser is demonstrated employing a digital micromirror device (DMD) in combination with a fixed grating. The diffraction property of four typical models of DMDs and its steering efficiency for the laser system are analyzed based on two-dimensional grating theory. By spatially modulating reflective patterns on a DMD, the stable, fast, and flexible tuning of lasing wavelength from 1930 nm to 2000 nm is achieved with wavelength tuning accuracy of 0.1 nm. The side-mode suppression ratio is larger than 50 dB around the 2 μm band with 3 dB linewidth less than 0.05 nm. The wavelength drift and power fluctuation are lower than 0.05 nm and 0.1 dB within 1 h at the room temperature, respectively.

Selective growth of either monolayer or bilayer graphene is of great importance. We developed a method to readily tune large area graphene growth from complete monolayer to complete bilayer. In an ambient pressure chemical vapor deposition process, we used the sample temperature at which to start the H2 flow as the control parameter and realized the change from monolayer to bilayer growth of graphene on Cu foil. When the H2 starting temperature was above 700°C, continuous monolayer graphene films were obtained. When the H2 starting temperature was below 350°C, continuous bilayer films were obtained. Detailed characterization of the samples treated under various conditions revealed that heating without the H2 flow caused Cu oxidation. The more the Cu substrate oxidized, the less graphene bilayer could form.

Delusions of schizophrenia have been found to be associated with alterations of some brain regions in structure and task-induced activation. However, the relationship between spontaneously occurring symptoms and spontaneous brain activity remains unclear. In the current study, 14 schizophrenic patients with delusions and 14 healthy controls underwent a resting-state functional magnetic resonance imaging (RS-fMRI) scan. Patients with delusions of schizophrenia patients were rated with Positive and Negative Syndrome Scale (PANSS) and Characteristics of Delusional Rating Scale (CDRS). Regional homogeneity (ReHo) was calculated to measure the local synchronization of the spontaneous activity in a voxel-wise way. A two-sample t-test showed that ReHo of the right anterior cingulate gyrus and left medial superior frontal gyrus were higher in patients, and ReHo of the left superior occipital gyrus was lower, compared to healthy controls. Further, among patients, correlation analysis showed a significant difference between delusion scores of CRDS and ReHo of brain regions. ReHo of the left medial superior frontal gyrus was negatively correlated with patients' CDRS scores but not with delusional PANSS scores. These results suggested that altered local synchronization of spontaneous brain activity may be related to the pathophysiology of delusion in schizophrenia.

Amphioxus is a best candidate for studying the evolutionary and developmental mechanisms of vertebrates, because of its vertebrate-like but much simpler morphology, embryonic development and genome structure. Producing live amphioxus embryos throughout the year is an ideal for comparative evolution and developmental studies. However, all amphioxus species have distinct breeding seasons in the wild and laboratory. We recently found that Chinese amphioxus B. belcheri could reproduce repeatedly beyond its natural breeding season when reared under proper conditions. In this study, we were able to extend further and produce embryos throughout the year from October 2011 to October 2012. We found all examined animals had spawned repeatedly during the examined period. In addition, both lancelets B. belcheri and B. japonicum could be induced to spawn by heat-shock method, although the induced spawning efficiency was not as high as that observed in the European lancelet. In general, we have succeeded in producing B. belcheri embryos almost daily throughout the year. This advancement will provide essential embryonic material for evolutionary and developmental studies, and have great implications for the cultivation and spawning induction of other amphioxus species.

Cephalochordate amphioxus is a promising model animal for studying the evolutionary and developmental mechanisms of vertebrates because its unique phylogenetic position, simple body plan and sequenced genome. However, one major drawback for using amphioxus as a model organism is the restricted supply of living embryos since they are available only during spawning season that varies from a couple of days to several months according to species. Therefore we are aiming to develop methods for obtaining viable amphioxus embryos in non-spawning season. In the current study, we found that Branchiostoma belcheri could develop their gonads and spawn consecutively in the laboratory when cultured in a low density at a high temperature (25-28 °C) supplied with sufficient food and proper cleanness. Among the approximate 150 observed animals, which spawned spontaneously between November and December 2011, 10% have spawned twice, 10% three times, and 80% four times, through April 2012. The quality and quantity of the gametes reproduced in the consecutive spawning have no obvious difference with those spawned once naturally. Spawning intervals varied dramatically both among different animals (from 1 to 5 months) and between intervals of a single individual (from 27 to 74 days for one animal). In summary, we developed a method with which, for the first time, consecutive spawnings of amphioxus in captivity can be achieved. This has practical implications for the cultivation of other amphioxus species, and eventually will greatly promote the utilization of amphioxus as a model system.

Second generation sequencing has been widely used to sequence whole genomes. Though various paired-end sequencing methods have been developed to construct the long scaffold from contigs derived from shotgun sequencing, the classical paired-end sequencing of the Bacteria Artificial Chromosome (BAC) or fosmid libraries by the Sanger method still plays an important role in genome assembly. However, sequencing libraries with the Sanger method is expensive and time-consuming. Here we report a new strategy to sequence the paired-ends of genomic libraries with parallel pyrosequencing, using a Chinese amphioxus (Branchiostoma belcheri) BAC library as an example. In total, approximately 12,670 non-redundant paired-end sequences were generated. Mapping them to the primary scaffolds of Chinese amphioxus, we obtained 413 ultra-scaffolds from 1,182 primary scaffolds, and the N50 scaffold length was increased approximately 55 kb, which is about a 10% improvement. We provide a universal and cost-effective method for sequencing the ultra-long paired-ends of genomic libraries. This method can be very easily implemented in other second generation sequencing platforms.