The single pulses of PSR J1921+1419 were examined in detail using high-sensitivity observations from the Five-hundred-meter Aperture Spherical radio Telescope (FAST) at a central frequency of 1250 MHz. The high-sensitivity observations indicate that the pulsar exhibits two distinct emission modes, which are classified as strong and weak modes based on the intensity of the single pulses. In our observations, the times spent in both modes are nearly equal, and each is about half of the total observation time. The minimum duration of both modes is $1\,P$ and the maximum duration is $13\,P$, where P is the pulsar spin period. Additionally, the mean intensity of the weak mode is less than half of that of the strong mode. Notably, the switching between these modes demonstrates a clear quasi-periodicity with a modulation period of approximately $10 \pm 2\,P$. An analysis of the polarisation properties of both modes indicates that they originate from the same region within the magnetosphere of the pulsar. Finally, the viewing geometry was analysed based on the kinematical effects.

Optical coherence tomography (OCT) and confocal microscopy are pivotal in retinal imaging, offering distinct advantages and limitations. In vivo OCT offers rapid, noninvasive imaging but can suffer from clarity issues and motion artifacts, while ex vivo confocal microscopy, providing high-resolution, cellular-detailed color images, is invasive and raises ethical concerns. To bridge the benefits of both modalities, we propose a novel framework based on unsupervised 3D CycleGAN for translating unpaired in vivo OCT to ex vivo confocal microscopy images. This marks the first attempt to exploit the inherent 3D information of OCT and translate it into the rich, detailed color domain of confocal microscopy. We also introduce a unique dataset, OCT2Confocal, comprising mouse OCT and confocal retinal images, facilitating the development of and establishing a benchmark for cross-modal image translation research. Our model has been evaluated both quantitatively and qualitatively, achieving Fréchet inception distance (FID) scores of 0.766 and Kernel Inception Distance (KID) scores as low as 0.153, and leading subjective mean opinion scores (MOS). Our model demonstrated superior image fidelity and quality with limited data over existing methods. Our approach effectively synthesizes color information from 3D confocal images, closely approximating target outcomes and suggesting enhanced potential for diagnostic and monitoring applications in ophthalmology.

We present evidence revealing that an object with specific properties can exhibit multiple stable falling postures at low Reynolds numbers. By scrutinizing the force equilibrium relationship of a fixed object at various attack angles and Reynolds numbers, we introduce a methodology that can obtain the stable falling postures of the object. This method saves computational resources and more intuitively presents the results in the full parameter domain. Our findings are substantiated by free-fall tests conducted through both physical experiments and numerical simulations, which validate the existence of multiple stable solutions in accordance with the interpolation results obtained with fixed objects. Additionally, we quantify the abundance and distribution patterns of stable falling postures for a diverse range of representative shapes. This discovery highlights the existence of multiple stable solutions that are universally present across objects of different shapes. The implications of this research extend to the design, stability control and trajectory prediction of all free and controlled flights in both air and water.

In this paper, we have experimentally demonstrated a high-power and high-brightness narrow-linewidth fiber amplifier seeded by an optimized fiber oscillator. In order to improve the temporal stability, the fiber oscillator consists of a composite fiber Bragg grating-based cavity with an external feedback structure. By optimizing the forward and backward pumping ratio, the nonlinear effects and stimulated Raman scattering-induced mode distortion of the fiber amplifier are suppressed comprehensively, accompanied with the simultaneous improvement of beam quality and output power. The laser brightness is enhanced further by raising the threshold of transverse mode instability by approximately 1.0 kW by coiling the gain fiber with a novel curvature shape. Finally, a 6 kW narrow-linewidth laser is achieved with beam quality (M2) of approximately 1.4. The laser brightness doubled compared to the results before optimization. To the best of our knowledge, it is the highest brightness narrow-linewidth fiber laser based on a one-stage master oscillator power amplification structure.

Large-scale outbreaks of the dinoflagellate Karenia mikimotoi caused substantial mortality of abalone, Haliotis discus hannai in Fujian, China in 2012, resulting in 20 billion in economic losses to abalone industries. However, the mechanism behind the mortality, especially the reaction of abalone to this microalgal toxicity, which possibly differed significantly from the former ‘fish killer’ strain in the South China Sea (SCS). Our study revealed that K. mikimotoi FJ-strain exhibited a four-fold higher haemolytic toxicity than the SCS-strain during the late exponential phase. At the microalgal cell density of 3 × 107 cell L−1, the FJ-strain caused abalone mortality of 67% in 48 h, with decreased granulocyte–hyalinocyts ratio and phagocytic activity by 58.96% and 75.64%, respectively, increased haemocyte viability by 4.8-fold and severe gill damage. The toxic effect only worked for the haemolytic toxicity from active algal cells, which were probably produced under the contact of algal cells and abalone gills. However, under exposure to the SCS-strain, more than 80% of individuals survived under aeration. The results indicated that FJ-strain was a new K. mikimotoi ecotype with stronger toxicity. It evoked severe effects, with complete abalone mortality within 24 h under the cascading effect of non-aeration (dissolved oxygen declined to 2.0 mg L−1), when exposed to K. mikimotoi FJ-strain at the above density. Thus, apart from the microalgal toxicity, DO depletion exacerbated the mortality of abalone in the experiment. The massive abalone mortalities in Fujian were probably caused by the combination of microalgal toxic effects and oxygen depletion, leading to immunological depression and histopathological disruption.

The Viséan–Serpukhovian boundary is poorly defined in South China, hampering regional and global stratigraphical correlations. The foraminiferal and conodont distribution of the Baping Formation in the carbonate-slope Danlu section permits the recognition of an interval from the middle Viséan to the uppermost Serpukhovian in a continuous succession. The base of the Serpukhovian in Danlu is recognized by the first occurrences of Janischewskina delicata, Howchinia subplana and questionable ‘Millerella’ tortula. At a slightly younger level, the conodont Lochriea ziegleri is first recorded. A calibration on the first occurrence of L. ziegleri in different basins at a global scale has been revised compared to auxiliary markers within the ammonoids and foraminifers. The late occurrence of L. ziegleri in the Danlu section also supports a lack of synchronicity in the global first occurrence of this taxon. This study calls for the recognition of a new base for the Serpukhovian under a far better correlation between different zonal schemes and fossil groups.

We report here the first hundred-watt continuouswave fiber gas laser in H2-filled hollow-core photonic crystal fiber (PCF) by stimulated Raman scattering. The pump source is a homemade narrow-linewidth fiber oscillator with a 3 dB linewidth of 0.15 nm at the maximum output power of 380 W. To efficiently and stably couple several-hundred-watt pump power into the hollow core and seal the gas, a hollow-core fiber end-cap is fabricated and used at the input end. A maximum power of 110 W at 1153 nm is obtained in a 5 m long hollow-core PCF filled with 36 bar H2, and the conversion efficiency of the first Stokes power is around 48.9%. This work paves the way for high-power fiber gas Raman lasers.

Fat deposition and lipid metabolism are closely related to the morphology, structure and function of mitochondria. The morphology of mitochondria between fusion and fission processes is mainly regulated by protein posttranslational modification. Intermittent fasting (IF) promotes high expression of Sirtuin 3 (Sirt3) and induces mitochondrial fusion in high-fat diet (HFD)-fed mice. However, the mechanism by which Sirt3 participates in mitochondrial protein acetylation during IF to regulate mitochondrial fusion and fission dynamics remains unclear. This article demonstrates that IF promotes mitochondrial fusion and improves mitochondrial function in HFD mouse inguinal white adipose tissue. Proteomic sequencing revealed that IF increased protein deacetylation levels in HFD mice and significantly increased Sirt3 mRNA and protein expression. After transfecting with Sirt3 overexpression or interference vectors into adipocytes, we found that Sirt3 promoted adipocyte mitochondrial fusion and improved mitochondrial function. Furthermore, Sirt3 regulates the JNK-FIS1 pathway by deacetylating malate dehydrogenase 2 (MDH2) to promote mitochondrial fusion. In summary, our study indicates that IF promotes mitochondrial fusion and improves mitochondrial function by upregulating the high expression of Sirt3 in HFD mice, promoting deacetylation of MDH2 and inhibiting the JNK-FIS1 pathway. This research provides theoretical support for studies related to energy limitation and animal lipid metabolism.

Pie charts are often used to communicate risk, such as the risk of driving. In the foreground-background salience effect (FBSE), foreground (probability of bad event) has greater salience than background (no bad event) in such a chart. Experiment 1 confirmed that the displays format of pie charts showed a typical FBSE. Experiment 2 showed that the FBSE resulted from a difference in cognitive efforts in processing the messages and that a foreground-emphasizing display was easier to process. Experiment 3 manipulated subjects’ information processing mindset and explored the interaction between displays format and information processing mindset. In the default mindset, careless subjects displayed a typical FBSE, while those who were instructed to be careful reported similar risk-avoidant behavior preference reading both charts. Suggestions for improving risk communication are discussed.

Direct numerical simulations are performed to investigate the wake transitions of the flow normal to a circular rotating disk. The diameter-thickness aspect ratio of the disk is $\chi =50$. The Reynolds number of the free stream is defined as $Re_s=U_\infty D/\nu$, with incoming flow velocity $U_\infty$, disk diameter $D$, and kinematic viscosity of the fluid $\nu$. The rotational motion of the disk is described by the Reynolds number of rotation $Re_r=\varOmega Re_s$, with non-dimensional rotation rate $\varOmega =\frac {1}{2}\omega D/U_\infty$, where $\omega$ is the angular rotation speed of the disk. Extensive numerical simulations are performed in the parameter space $50 \leqslant Re_s \leqslant 250$ and $0 \leqslant Re_r \leqslant 250$, in which six flow regimes are identified as follows: the axisymmetric state, the low-speed steady rotation (LSR) state, the high-speed steady rotation (HSR) state, the low-speed unsteady rotation (LUR) state, the rotational vortex shedding state, and the chaotic state. Although plane symmetry exists in the wake when the disk is stationary, a small rotation will immediately destroy its symmetry. However, the vortex shedding frequencies and wake patterns of the stationary disk are inherited by the unsteady rotating cases at low $Re_r$. A flow rotation rate jump is observed at $Re_s\approx 125$. The LUR state is intermediate between the LSR and HSR states. Due to the rotational motion, the wake of the disk enters the steady rotation state earlier at large $Re_r$, and is delayed into the vortex shedding state in the whole range of $Re_r$. In the steady rotation states (LSR and HSR), the steady flow rotation rate is linearly correlated with the disk rotation rate. It is found that the rotation of the disk can restrain the vortex shedding. The chaotic state can be regularized by the medium rotation speed of the disk.

Due to the lack of research between the inner layers in the structure of colonic mucous and the metabolism of fatty acid in the constipation model, we aim to determine the changes in the mucous phenotype of the colonic glycocalyx and the microbial community structure following treatment with Rhubarb extract in our research. The constipation and treatment models are generated using adult male C57BL/6N mice. We perform light microscopy and transmission electron microscopy (TEM) to detect a Muc2-rich inner mucus layer attached to mice colon under different conditions. In addition, 16S rDNA sequencing is performed to examine the intestinal flora. According to TEM images, we demonstrate that Rhubarb can promote mucin secretion and find direct evidence of dendritic structure-linked mucus structures with its assembly into a lamellar network in a pore size distribution in the isolated colon section. Moreover, the diversity of intestinal flora has noticeable changes in constipated mice. The present study characterizes a dendritic structure and persistent cross-links have significant changes accompanied by the alteration of intestinal flora in feces in models of constipation and pretreatment with Rhubarb extract.

A droplet impinging on a superhydrophobic substrate in an electric field is an important process in droplet manipulation and electrostatic spraying. Here, the entire impinging dynamic of the droplet in a vertical electric field is studied by a visualization experiment and numerical simulation with OpenFOAM. We investigate the effect of an electrostatic force on droplet impact in depth, where four ejection modes and three rebound modes are found experimentally. In particular, the filamentous ejecting phenomenon occurs after a droplet impinging on a superhydrophobic substrate is first discovered. In the numerical simulation, the strong coupling between the dynamic distribution of the interface electric charge and the evolution of the droplet profile can lead to different ejection modes, and the different ejection behaviours are caused by the combined effects of electrostatic pressure, capillary pressure, dynamic pressure and static pressure on the droplet apex. A charge scaling law for the ejection droplets is proposed. Furthermore, a set of theoretical models is established, which can successfully predict the threshold electric capillary number for different droplet ejection modes. The results reveal some important characteristics for a droplet impinging on a superhydrophobic surface in an electric field, which could facilitate the design of electrically operated droplet equipment and guide the safe and stable operation of the device.

The late Palaeozoic Yong’an–Meizhou depression belt is an important iron (Fe) and polymetallic metallogenic belt in southern China. It has undergone a transformation from Tethys to the circum-Pacific tectonic domain. The Luoyang deposit is one of the typical Fe skarn deposits in the Yong’an–Meizhou depression belt of eastern China. Garnet is a characteristic mineral in the deposit. Two generations of garnets are detected in the deposit based on their textural characteristics and trace-element contents, and are represented by Fe-enriched andradite. The first generation of garnets (Grt1) have two types of garnets (Grt1-A and Grt1-B). Type A garnets of the first generation (Grt1-A) (Adr80-88) replaced by massive diopside-magnetite assemblage exhibit distinct oscillatory zonings and display patterns of enriched light rare earth elements (LREE) to weak heavy rare earth elements (HREE), with weak negative to positive Eu anomalies, and highest U, ΣREE and Sn contents. Type B garnets of the first generation (Grt1-B) are irregular zones (Adr94-96) coexisting with magnetite, in which Grt1-A is generally dissolved, and have obviously LREE-enriched and HREE-depleted patterns, with weak negative to positive Eu anomalies, and moderate U, ΣREE and Zn contents. Garnets of the second generation (Grt2) (Adr96-99) that replaced massive magnetite together with sphalerite show unzoned patterns, with a flat REE pattern and pronounced negative Eu anomalies as well as contents of lowest U and ΣREE, and highest W. The substitution of REEs in garnets occurs as [X2+]VIII –1[REE3+]VIII +1[Si4+]IV –1[Z3+]IV +1in an Al-enriched environment. Luoyang hydrothermal fluids shifted from reducing conditions with relatively high-U and -ΣREE characteristics to oxidizing conditions with relatively low-U and -ΣREE characteristics. The reduced siderophile elements and increased fO2 in fluid during Grt1-B formation caused magnetite mineralization and reduced Zn contents during Grt2 formation, causing the deposition of sphalerite. All garnets formed from magmatic fluid and were controlled by infiltrative metasomatism in an opened system.

Nowadays, automated essay evaluation (AEE) systems play an important role in evaluating essays and have been successfully used in large-scale writing assessments. However, existing AEE systems mostly focus on grammar or shallow content measurements rather than higher-order traits such as ideas. This paper proposes a new formulation of graph-based features for concept maps using word embeddings to evaluate the quality of ideas for Chinese compositions. The concept map derived from the student’s composition is composed of the concepts appearing in the essay and the co-occurrence relationship between the concepts. By utilizing real compositions written by eighth-grade students from a large-scale assessment, the scoring accuracy of the computer evaluation system (named AECC-I: Automated Evaluation for Chinese Compositions—Ideas) is higher than the baselines. The results indicate that the proposed method deepens the construct-relevant coverage of automatic ideas evaluation in compositions and that it can provide constructive feedback for students.

Ship domain is an important theory in ship collision avoidance and an effective collision detection method. First, several classical ship domain models are used in experiments. The results show that the alarm rate is too high in busy waters, leading to greatly reduced practicality of the model. Potential collision risk cannot be detected effectively, especially for a ship with restricted manoeuvrability, which is usually regarded as an overtaken ship due to its navigation characteristics. Therefore, it is necessary to fully consider the interference of other ships to ships with limited manoeuvrability in an encounter situation. A novel ship domain model for ships with restricted manoeuvrability in busy waters is proposed. Considering the navigation characteristics of a ship with restricted manoeuvrability and the influence of the ship–ship effect, an algorithm to determine the boundary of the ship domain model is given by force and moment equations. AIS trajectory data of the North Channel of the Yangtze River Estuary are used to perform a comparative experiment, and four classical ship domain models are employed to perform comparative experiments. The results show that the alarm rates of the novel ship domain model are 7⋅608%, 15⋅131%, 55⋅785% and 7⋅608% lower than those of the other four classical models, and this outcome can effectively reduce the high false alarm rate produced by other models in this environment.

During recent stratigraphical and micropaleontological investigations of the Gulupu section in Tüna, Yadong, of the Eocene Zhepure Formation, numerous holoplanktonic mollusks (pteropods) were recovered. Four species, assignable to two genera of pteropods (including Limacina yadongensis new species) were systematically described and illustrated, and a gastropod-bivalve biofacies was identified. This is the first report of Eocene (Ypresian) pteropods in southern Tibet; the same stratum also yields many other neritic faunas. The data presented in this study suggest that a semi-closed restricted gulf in the Tüna area existed and the occurrence of pteropods in Tüna may indicate transport from more open, deep water by oceanic currents during early Eocene. Based on the analysis of paleogeographical distribution of pteropods, it indicates that a Tethys seaway existed during the early Eocene (Ypresian).

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