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The electron microscope (EM) remains the predominant technique for elucidating intricate details of the animal nervous system at the nanometer scale. However, accurately reconstructing the complex morphology of axons and myelin sheaths poses a significant challenge. Furthermore, the absence of publicly available, large-scale EM datasets encompassing complete cross sections of the corpus callosum, with dense ground truth segmentation for axons and myelin sheaths, hinders the advancement and evaluation of holistic corpus callosum reconstructions. To surmount these obstacles, we introduce the AxonCallosumEM dataset, comprising a 1.83 times 5.76mm EM image captured from the corpus callosum of the Rett Syndrome (RTT) mouse model, which entail extensive axon bundles. We meticulously proofread over 600,000 patches at a resolution of 1024 times 1024, thus providing a comprehensive ground truth for myelinated axons and myelin sheaths. Additionally, we extensively annotated three distinct regions within the dataset for the purposes of training, testing, and validation. Utilizing this dataset, we develop a fine-tuning methodology that adapts Segment Anything Model (SAM) to EM images segmentation tasks, called EM-SAM, enabling outperforms other state-of-the-art methods. Furthermore, we present the evaluation results of EM-SAM as a baseline., 9 pages, 6 figures

The effects of Ta and Zr content on the stability, elastic properties and electronic structure of Ti-Zr-Ta alloy phase were studied by first principles calculation method based on density functional theory. Moreover, Ti-Zr-Ta alloy was fabricated by spark plasma sintering (SPS) using spherical Ti powder,Ta powder, and Ti-Zr-Ta alloy powder produced by the plasma rotation electrode process (PREP). Afterward, the effects of sintering temperature, Zr and Ta content on the microstructure and mechanical properties of the alloy samples were investigated. The results showed that sintering temperature, Ta and Zr content were the key factors which affected the densification. When the sintering temperature was raised, the relative density and mechanical properties of Ti-Zr-Ta alloy were significantly increased. The first- principles calculation also indicated that Ti-1Zr-Ta possesses the lowest Young’s modulus and the best ductility, showing great potential of biomedical applications which agrees with the results of experimental results of alloy preparation.

With increasing bus capacity, operational intensity, etc., urban public transport emergencies are more and more characterized by heavy loads with high frequency. To build a collaborative public transport emergency command system (CPTECS) based on existing systems and datasets, bus emergency scenes and categories of sources of danger are defined. Emergency cases in Beijing are selected for analysis, designing new means of encoding and expanding the decision attributes of the rough set model. Cellular genetic algorithm (CGA) is used to screen key hazards highly correlated to existing information systems. By comparing with genetic algorithm (GA), it is found that CGA can better solve attribute reduction problems of multi-decision attribute rough set in stability, convergence quality, and algorithm efficiency. Based on the meteorological hazards screened out, a CPTECS is designed, enriching research in such territories. Research findings provide quantitative support for the design of CPTECS, and have certain practical significance.

We prove Torelli-type uniqueness theorems for both ALG$^*$ gravitational instantons and ALG gravitational instantons which are of order $2$. That is, the periods uniquely characterize these types of gravitational instantons up to diffeomorphism. We define a period mapping $\mathscr{P}$, which we show is surjective in the ALG cases, and open in the ALG$^*$ cases. We also construct some new degenerations of hyperk\"ahler metrics on the K3 surface which exhibit bubbling of ALG$^*$ gravitational instantons.

We develop a Fredholm Theory for the Hodge Laplacian in weighted spaces on ALG$^*$ manifolds in dimension four. We then give several applications of this theory. First, we show the existence of harmonic functions with prescribed asymptotics at infinity. A corollary of this is a non-existence result for ALG$^*$ manifolds with non-negative Ricci curvature having group $\Gamma = \{e\}$ at infinity. Next, we prove a Hodge decomposition for the first de Rham cohomology group of an ALG$^*$ manifold. A corollary of this is vanishing of the first betti number for any ALG$^*$ manifold with non-negative Ricci curvature. Another application of our analysis is to determine the optimal order of ALG$^*$ gravitational instantons., Comment: 35 pages; final version; to appear in J. Reine Angew. Math. (Crelle's Journal)

We investigate the collapsing geometry of hyperk\"ahler 4-manifolds. As applications we prove two well-known conjectures in the field. (1) Any collapsed limit of unit-diameter hyperk\"ahler metrics on the K3 manifold is isometric to one of the following: the quotient of a flat 3-torus by an involution, a singular special K\"ahler metric on the 2-sphere, or the unit interval. (2) Any complete hyperk\"ahler 4-manifold with finite energy (i.e., gravitational instanton) is asymptotic to a model end at infinity., Comment: A conjecture on the L2-curvature energy was added in Section 7.3. To appear in Acta Mathematica

We investigate the collapsing geometry of hyperkähler 4-manifolds. As applications we prove two well-known conjectures in the field. (1) Any collapsed limit of unit-diameter hyperkähler metrics on the K3 manifold is isometric to one of the following: the quotient of a flat 3-torus by an involution, a singular special Kähler metric on the 2-sphere, or the unit interval. (2) Any complete hyperkähler 4-manifold with finite energy (i.e., gravitational instanton) is asymptotic to a model end at infinity., A conjecture on the L2-curvature energy was added in Section 7.3. To appear in Acta Mathematica

We show that any ALH$^*$ gravitational instanton arises from the Tian-Yau construction on a weak del Pezzo surface minus an anticanonical elliptic curve. A corollary is that any ALH$^*$ gravitational instanton can be compactified to a rational elliptic surface with respect to a hyperkaehler rotation of the weak del Pezzo complex structure.

How team work crafting supports agility and adaptiveness to dynamic environments.

In order to solve the increasingly serious problems of energy and environment, microalgae are used as a raw material for extracting lipids to produce biodiesel. Prior to the extraction of lipids, microalgae were treated with high-voltage pulsed electric field (PEF) to break the cell membrane. It was found that the lipid extraction yield depends on the electric field strength (E) and the specific energy input (Wsp), and has a certain relationship with the cell disintegration rate of Chlorella. The perforation degree of the Chlorella's cell membrane by PEF treatment is controllable, moderate perforation can be ensured by controlling the power parameters. PEF treatment significantly improved the extraction yield of lipids. Compared with the test samples without PEF treatment, PEF treatment increased the lipid extraction yields by up to 166.67%. However, an excessively high voltage will cause the quality of the extracted biodiesel to decrease.

In this study, spent fluid catalytic (SFCC) catalyst was used to prepare geopolymer as a replacement of metakaolin. Through the response surface experiment method, the single-factor influence degree and interactive influence degree of the content, alkali content and water content of SFCC catalysts as well as the particle size of SFCC catalysts on the compressive strength of geopolymers were analyzed. According to the quadratic model, the replacement of metakaolin with an appropriate amount of SFCC catalyst will improve the compressive strength of the geopolymers, but the replacement of metakaolin with an excessive amount of SFCC catalyst will weaken the compressive strength of geopolymers. a highest compressive strength of 41.22 MPa was obtained with the 20% replacement of SFCC catalysts, which was 21.6% higher than the geopolymer without SFCC catalyst. The microstructure and crystal structure analysis indicated that SFCC catalyst partially participated in the geopolymerization.

Atmospheric pressure plasma jet (APPJ) has a significant effect on the inactivation of pathogenic microorganisms such as bacteria, virus and fungus. However, sterilization effect of APPJ is restricted by many factors: forms of the power supply (pulse, AC, DC, etc.), parameters of the voltage (amplitude, frequency), time and distance of processing, and the parameters of working gas. In this paper, the system consisting of the pulse power supply and the plasma generation device which uses coaxial cylinder tube, are developed by our research team independently. The system can generate plasma jets of low temperature under atmospheric pressure, using helium as working gas. In the experiment, Escherichia coli, which is typical and common in our environment, was used as the processing object to analyze the sterilization effect of APPJ under different power supply parameters, gas flow rate and processing time. In this paper the composition of plasma jet was analyzed by testing infrared spectra of it and the structure of bacteria was observed by scanning electron microscope (SEM) to study the principle of sterilization. The experimental results show that the active ingredients in APPJ will directly act on bacteria, making the bacterial structure destroyed, cell components lost completely and finally the bacteria inactivated; or the cell fragmentation will occur under the electric field, leading to the thorough loss of bacterial morphology. With the increase of the voltage amplitude or the gas velocity, the sterilization ratio of Escherichia coli increases continuously. Also lengthening the processing time is an effective measure to enhance the sterilization ratio of APPJ. When the processing time exceeds 1 minute, sterilization ratios under different parameters of power supply and gas flow rate can reach 90% or more. The sterilization effect of plasma jet can be obviously seen. Compared to traditional methods such as thermal, chemical and radiate sterilization, APPJ sterilization is more effective, cleaner and free from contamination.

We exhibit families of Ricci-flat Kahler metrics on K3 surfaces which collapse to an interval, with Tian-Yau and Taub-NUT metrics occurring as bubbles. There is a corresponding continuous surjective map from the K3 surface to the interval, with regular fibers diffeomorphic to either 3-tori or Heisenberg nilmanifolds., Comment: 95 pages

Accumulating evidences have shown that apoptosis plays an important role in mediating the therapeutic effects and toxicity of arsenic. Fas and Bax genes are critical regulatory genes for apoptosis. In this study, we investigated the association between levels of Fas and Bax expression and the three arsenic species (inorganic arsenic (iAs), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA)) in vivo and vitro. Three arsenic species in urine were measured and levels of Fas and Bax expression were examined by the quantitative real-time PCR (qPCR) for all subjects. We found that Fas and Bax mRNA expression in the exposed group were significantly higher than that in the control group. The levels of gene expression were positively correlated with the concentrations of urinary iAs, MMA and DMA in all subjects. Sodium arsenite induced Fas and Bax mRNA expression, then MMA and DMA did not induce mRNA expression in MDA-MB-231 and XWLC-05 cells. The findings of the present study indicated that iAs, MMA, and DMA had different effects on expression of Bax and Fas gene.

Heterogeneity of mitogen-activated protein kinase (MAPK) activation in genetically identical cells, which occurs in response to epidermal growth factor receptor (EGFR) signaling, remains poorly understood. MAPK cascades integrate signals emanating from different EGFR spatial locations, including the plasma membrane and endocytic compartment. We previously hypothesized that in EGF-stimulated cells the MAPK phosphorylation (pMAPK) level and activity are largely determined by the spatial organization of the EGFR clusters within the cell. For experimental testing of this hypothesis, we used super-resolution microscopy to define EGFR clusters by receptor numbers (N) and average intracluster distances (d). From these data, we predicted the extent of pMAPK with 85% accuracy on a cell-to-cell basis with control data returning 54% accuracy (P < 0.001). For comparison, the prediction accuracy was only 61% (P = 0.382) when the diffraction-limited averaged fluorescence intensity/cluster was used. Large clusters (N ≥ 3) with d > 50 nm were most predictive for pMAPK level in cells. Electron microscopy revealed that these large clusters were primarily localized to the limiting membrane of multivesicular bodies (MVB). Many tighter packed dimers/multimers (d < 50 nm) were found on intraluminal vesicles within MVBs, where they were unlikely to activate MAPK because of the physical separation. Our results suggest that cell-to-cell differences in N and d contain crucial information to predict EGFR-activated cellular pMAPK levels and explain pMAPK heterogeneity in isogenic cells.

Heterogeneity of mitogen-activated protein kinase (MAPK) activation in genetically identical cells, which occurs in response to epidermal growth factor receptor (EGFR) signaling, remains poorly understood. MAPK cascades integrate signals emanating from different EGFR spatial locations, including the plasma membrane and endocytic compartment. We previously hypothesized that in EGF-stimulated cells the MAPK phosphorylation (pMAPK) level and activity are largely determined by the spatial organization of the EGFR clusters within the cell. For experimental testing of this hypothesis, we used super-resolution microscopy to define EGFR clusters by receptor numbers (N) and average intracluster distances (d). From these data, we predicted the extent of pMAPK with 85% accuracy on a cell-to-cell basis with control data returning 54% accuracy (P < 0.001). For comparison, the prediction accuracy was only 61% (P = 0.382) when the diffraction-limited averaged fluorescence intensity/cluster was used. Large clusters (N ≥ 3) with d > 50 nm were most predictive for pMAPK level in cells. Electron microscopy revealed that these large clusters were primarily localized to the limiting membrane of multivesicular bodies (MVB). Many tighter packed dimers/multimers (d < 50 nm) were found on intraluminal vesicles within MVBs, where they were unlikely to activate MAPK because of the physical separation. Our results suggest that cell-to-cell differences in N and d contain crucial information to predict EGFR-activated cellular pMAPK levels and explain pMAPK heterogeneity in isogenic cells. European Commission - Seventh Framework Programme (FP7) Wellcome Trust National Institutes of Health Dimbleby Cancer Care KCL-UCL Comprehensive Cancer Imaging Centre (CCIC)

In this paper, we focus on the geometry of compact conformally flat manifolds $(M^n,g)$ with positive scalar curvature. Schoen-Yau proved that its universal cover $(\widetilde{M^n},\tilde{g})$ is conformally embedded in $\mathbb{S}^n$ such that $M^n$ is a Kleinian manifold. Moreover, the limit set of the Kleinian group has Hausdorff dimension $0$, then the above inequality is strict. Moreover, the above upper bound is sharp. As applications, we obtain some topological rigidity and classification theorems in lower dimensions., Comment: We added some new rigidity results for nonnegative fractional curvature (Theorem 1.3, Theorem 1.4, Theorem 1.5). Also we obtained a sharp upper bound in the nonnegative fractional curvature case (see Theorem 1.1)

In this paper, we introduce a direct method of moving spheres for the nonlocal fractional Laplacian $(-\triangle)^{\alpha/2}$ for $0

OBJECTIVES The purpose of this study was to evaluate the elasticity of the abdominal aorta in passively smoking rabbits using echo-tracking technology and pathologic examination. METHODS Fifty-four male New Zealand White rabbits were randomly divided into a passive smoking group and a normal control group. The elasticity indicators for the abdominal aorta of the rabbits were measured by means of echo tracking, which was performed before and 1, 2, and 3 months after passive smoking. Measured indicators included the pressure-strain elastic modulus, stiffness, arterial compliance, augmentation index, and pulse wave velocity. After the completion of the in vivo measurements, rabbits were euthanized randomly, and the corresponding arterial sites were resected for pathologic examination and in vitro measurement of vascular elasticity. RESULTS The echo-tracking technology used in our research proved that the elastic modulus, stiffness, and pulse wave velocity gradually increased with time by passive smoking, whereas arterial compliance decreased by passive smoking. Pathologic examination and in vitro measurements were performed and further confirmed the observed in vivo results. CONCLUSIONS Passive smoking can injure arteries and reduce arterial elasticity. Echo-tracking technology is an accurate, noninvasive, and reliable method for analysis of the impact of passive smoking on arterial elasticity and detection arterial injury, which also can provide a new instructional basis for prevention and treatment of several arterial diseases.

Pulsed electric field is a novel non-thermal process technology. It could be applied in the extraction of functional components from plant for its irreversible disintegration on plant cell membrane. PEF treatment caused an irreversible disintegration on the cellular membrane of raspberry cell and the extraction yield of anthocyanins from raspberry was linearly correlated to the treatment pulses of PEF. During the extraction, Cyanidin-3-glucoside, the major anthocyanins in raspberry was found to be significantly degraded by PEF. The degradation effects of Cyanidin-3-glucoside decreased with the increase of the electric field or treatment time. In the spectra curves of Cyanidin-3-glucoside treated by PEF, the intensity of the peak at 333 nm increased as electric field and treatment time increased, while the intensity of the peak at 519 nm and the shoulder at 430 nm decreased, indicating Cyanidin-3-glucoside was degraded into chalcone.

We discuss aspects of the global topology of moduli spaces of hyperkähler metrics. If the second Betti number is larger than $4$, we show that each connected component of these moduli spaces is not contractible. Moreover, in certain cases, we show that the components are simply connected and determine the second rational homotopy group. By that, we prove that the rank of the second homotopy group is bounded from below by the number of orbits of MBM-classes in the integral cohomology. \\ An explicit description of the moduli space of these hyperkähler metrics in terms of Torelli theorems will be given. We also provide such a description for the moduli space of Einstein metrics on the Enriques manifold. For the Enriques manifold, we also give an example of a desingularization process similar to the Kummer construction of Ricci-flat metrics on a Kummer $K3$ surface.\\ We will use these theorems to provide topological statements for moduli spaces of Ricci-flat and Einstein metrics in any dimension larger than $3$. For a compact simply connected manifold $N$ we show that the moduli space of Ricci flat metrics on $N\times T^k$ splits homeomorphically into a product of the moduli space of Ricci flat metrics on $N$ and the moduli of sectional curvature flat metrics on the torus $T^k$.