Spatial Cascaded Clustering and Weighted Memory for Unsupervised Person Re-identification

Recent unsupervised person re-identification (re-ID) methods achieve high performance by leveraging fine-grained local context. These methods are referred to as part-based methods. However, most part-based methods obtain local contexts through horizontal division, which suffer from misalignment due to various human poses. Additionally, the misalignment of semantic information in part features restricts the use of metric learning, thus affecting the effectiveness of part-based methods. The two issues mentioned above result in the under-utilization of part features in part-based methods. We introduce the Spatial Cascaded Clustering and Weighted Memory (SCWM) method to address these challenges. SCWM aims to parse and align more accurate local contexts for different human body parts while allowing the memory module to balance hard example mining and noise suppression. Specifically, we first analyze the foreground omissions and spatial confusions issues in the previous method. Then, we propose foreground and space corrections to enhance the completeness and reasonableness of the human parsing results. Next, we introduce a weighted memory and utilize two weighting strategies. These strategies address hard sample mining for global features and enhance noise resistance for part features, which enables better utilization of both global and part features. Extensive experiments on Market-1501 and MSMT17 validate the proposed method's effectiveness over many state-of-the-art methods

Load spectrum generation of machining center based on rainflow counting method

Reliability bench tests and probability design method are two important means to improve the reliability of machine tools, while the load spectrum of machine tools is the foundation of reliability bench tests and probability design. According to the load spectrum, the actual working conditions can be simulated in laboratories. A dynamic load spectrum generation method is proposed to establish a representative load spectrum. Firstly, the cutting load measuring system is established based on the characteristics of the cutting loads, and then the actual cutting experiments designed by the orthogonal experimental method are conducted on the basis of the typical cutting conditions in laboratories. Secondly, the counting method of the cutting loads cycles is presented based on the dynamic load characteristics of a machining center. And loads cycles are counted by the proposed counting method, and then a rainflow matrix is formed. Thirdly, in order to improve the precision of the load spectrum the extrapolation of the loads is carried out using the parametric extrapolation method. Then the probability distribution functions of the mean and amplitude of the cutting loads are provided by the K-S goodness-of-fit test method. The case study indicates that the radial force, axial force, and cutting torque of the tested machining center follow gamma, normal, and Weibull distributions with different parameters, respectively. Finally, the joint distribution function of the mean and amplitude of the radial force, axial force, and cutting torque is obtained by using a combination of statistical analysis method, and the two-dimensional load spectrum of the MC is compiled

C-Type Lectin in Chlamys farreri (CfLec-1) Mediating Immune Recognition and Opsonization

Background: C-type lectins are a superfamily of Ca 2+ dependent carbohydrate-recognition proteins that play significant diverse roles in nonself-recognition and clearance of invaders. Though they are well characterized in vertebrates, the study of the potential function and mechanism of C-type lectins in invertebrate immunity is still in its infancy. Methodology: A C-type lectin (CfLec-1) from scallop Chlamys farreri, a dominant cultured mollusk species in China, was selected to investigate its mRNA expression, localization and the possible functions in innate immunity in the present study. After scallop was stimulated by three typical PAMPs, the mRNA expression of CfLec-1 in hemocytes was poles apart. It was significantly up-regulated (p,0.01) after scallops were stimulated by LPS or b-glucan, but significantly down-regulated (p,0.01) after PGN stimulation. The binding ability of recombinant CfLec-1 (designated as rCfLec-1) towards eight PAMPs was investigated subsequently by PAMPs microarray, which revealed rCfLec-1 could bind LPS, PGN and mannan in vitro, indicating CfLec-1 served as a PRR involved in the pathogen recognition. Immunofluorescence assay with polyclonal antibody specific for CfLec-1 revealed that CfLec-1 was mainly located in the mantle and gill of the scallop. CfLec-1 could bind to the surface of scallop hemocytes and recruited hemocytes to enhance their encapsulation in vitro, and this process could be specifically blocked by anti-rCfLec-1 antibody. Meanwhile, rCfLec-1 could also enhance the phagocytic activity of scallop hemocytes against Escherichia coli

A solar wind-derived water reservoir on the Moon hosted by impact glass beads

The past two decades of lunar exploration have seen the detection of substantial quantities of water on the Moon’s surface. It has been proposed that a hydrated layer exists at depth in lunar soils, buffering a water cycle on the Moon globally. However, a reservoir has yet to be identified for this hydrated layer. Here we report the abundance, hydrogen isotope composition and core-to-rim variations of water measured in impact glass beads extracted from lunar soils returned by the Chang’e-5 mission. The impact glass beads preserve hydration signatures and display water abundance profiles consistent with the inward diffusion of solar wind-derived water. Diffusion modelling estimates diffusion timescales of less than 15 years at a temperature of 360 K. Such short diffusion timescales suggest an efficient water recharge mechanism that could sustain the lunar surface water cycle. We estimate that the amount of water hosted by impact glass beads in lunar soils may reach up to 2.7 × 1014 kg. Our direct measurements of this surface reservoir of lunar water show that impact glass beads can store substantial quantities of solar wind-derived water on the Moon and suggest that impact glass may be water reservoirs on other airless bodies

Evaluating Different Methods for Estimating Diameter at Breast Height from Terrestrial Laser Scanning

The accurate measurement of diameter at breast height (DBH) is essential to forest operational management, forest inventory, and carbon cycle modeling. Terrestrial laser scanning (TLS) is a measurement technique that allows rapid, automatic, and periodical estimates of DBH information. With the multitude of DBH estimation approaches available, a systematic study is needed to compare different algorithms and evaluate the ideal situations to use a specific algorithm. To contribute to such an approach, this study evaluated three commonly used DBH estimation algorithms: Hough-transform, linear least square circle fitting, and nonlinear least square circle fitting. They were each evaluated on their performance using two forest types of TLS data under numerous preprocessing conditions. The two forest types were natural secondary forest and plantation. The influences of preprocessing conditions on the performance of the algorithms were also investigated. Results showed that among the three algorithms, the linear least square circle fitting algorithm was the most appropriate for the natural secondary forest, and the nonlinear least square circle fitting algorithm was the most appropriate for the plantation. In the natural secondary forest, a moderate gray scale threshold of three and a slightly large height bin of 0.24 m were the optimal parameters for the appropriate algorithm of the multi-scan scanning method, and a moderate gray scale threshold of three and a large height bin of 1.34 m were the optimal parameters for the appropriate algorithm of the single-scan scanning method. A small gray scale threshold of one and a small height bin of 0.1 m were the optimal parameters for the appropriate algorithm of the single-scan scanning method in the plantation

High-Expressed Macrophage Scavenger Receptor 1 Predicts Severity Clinical Outcome in Transplant Patient in Idiopathic Pulmonary Fibrosis Disease

Background. Lung transplantation has been performed worldwide and admitted as an effective treatment for patients with various end-stage lung diseases. However, limit reliable clinical indicators exist to identify patients at high risk for allograft failure in lung transplant recipients. The recent advances in the knowledge of immunological aspects of the pulmonary diseases, for that innate macrophage activation, are induced by pathogen or pathogen-derived molecules and widely accepted as the critical evidence among the pathogenesis of lung inflammation and fibrosis. This study was aimed at evaluating the clinical significance of CD86- and macrophage scavenger receptor 1- (MSR1-) positive cells during the development of idiopathic pulmonary fibrosis (IPF) and pulmonary arterial hypertension (PAH), and their potential roles in the prediction of the outcomes after lung transplantation were examined. Methods. Tissues from lung transplantation for 37 IPF and 15 PAH patients from the Department of Cardiothoracic Surgery in Wuxi People’s Hospital from December 2015 to December 2016 were analyzed by immunohistochemistry (IHC) for detecting the expression and CD86 and MSR1 and correlated with clinical events after lung transplantation. Results. IHC results showed that the expression of MSR1, IL-13, and arginase-1 (Arg1) but not CD86 in the lung section of IPF patients was dramatically enhanced when compared with that of PAH patients. The expression of MSR1, IL-13, and Arg1 but not CD86 in the lung from IPF patients with smoking was significantly increased when compared with that from nonsmoking subjects. In addition, the expression of MSR1-positive cells in IPF subjects with Klebsiella pneumoniae infection was dramatically enhanced than that in noninfection subjects. MSR1-positive macrophages were negatively associated with FEV1 and with FVC but not associated with TLC and with TLCO. However, CD86-positive macrophages were not significantly associated with the above lung function-related factors. Furthermore, MSR1 had a higher area under the ROC curve (AUC) than CD86 for IPF diagnosis. Survival analysis indicated that high levels of MSR1-positive macrophages had a worse prognostic effect for IPF patients with lung transplantation. Conclusion. Our study indicates the clinical significance of Klebsiella pneumoniae infection-related MSR1-positive cells in IPF progression, and it could be a prognostic marker in IPF after the lung transplant; development strategies to reduce the expression of MSR1-positive macrophages in IPF may be beneficial for the lung transplant

Impact of Land Use/Cover Change on Yangtze River Delta Urban Agglomeration Ecosystem Services Value: Temporal-Spatial Patterns and Cold/Hot Spots Ecosystem Services Value Change Brought by Urbanization

Land use/cover change (LUCC) from increased urbanization significantly impacts regional ecosystem services. Based on a cold/hot spots analysis, this paper used grain yield, food prices, price index statistics, and a land use thematic map to study the impact of LUCC on four ecosystem services values (ESVs) in the Yangtze River Delta urban agglomeration, and determine the spatial differences resulting from the rapid urbanization LUCC. The correlation between the four ecosystem services was then studied and sensitivity analyses conducted to investigate whether any changes in the ESVs could lead to unacceptable unit value transfer uncertainties. It was found that most urban land was converted from farmland, and that before 2000, the total ESVs and the regulating services values (RSVs) increased significantly, after which it declined, the provisioning services values (PSVs) declined year on year, the habitat services value (HSV) and cultural and amenity services value (CSV) declined sharply after 2000, and the spatial distribution of the four ESVs were significantly different. Over time, it was found that the hot spots were shrinking and the cold spots were spreading. The provisioning services were found to be negatively correlated with habitat services and cultural and amenity services, the regulating services were weakly positively correlated with the provisioning services and significantly positively correlated with the habitat services and cultural and amenity services, and the habitat services were significantly positively correlated with cultural and amenity services. In the Yangtze River Delta urban agglomeration, the water area is the most important for the total ESVs, followed by non-bush forest. Paddy field is ranked third. Dryland, bush, grassland, and wetland are less important. The importance of barren land is almost zero. This research provides the government with a scientific basis from which to formulate spatial planning and environmental protection policies for ecological sustainable development in the Yangtze River Delta urban agglomeration

Electromagnetic Design and Analysis of Permanent Magnet Linear Synchronous Motor

Since permanent magnet linear synchronous motors are widely used in fatigue testing, in this paper, the thrust of a permanent magnet linear synchronous motor (PMLSM) is amplified more than 10 times by the method of resonance. Firstly, the air gap magnetic field is analyzed by the equivalent magnetization current method (EMC), the electromagnetic thrust is calculated, and the expression is given by the Maxwell tensor method. The vibration analysis of the whole machine is used to obtain the conditions under which the motor resonates. The dynamic and static characteristics of the motor are analyzed through finite element simulation, the results of the motor design are judged to be reasonable, and the theoretical calculation results are compared with the simulation results to verify the accuracy of the theoretical calculation. The accuracy of the simulation results is verified by static force experiments. Finally, the rated thrust of the motor was enlarged more than 10 times by resonance experiments

The effect of nickel on the carbide precipitation behavior in Cr–Mo–V hot-working die steel

The addition of small amount of nickel to hot-working die steel has been found to be beneficial for hardenability and toughness. In this paper, the addition of nickel to Cr–Mo–V hot-working die steel was studied to improve hardenability, and the inherent mechanism of enhancing toughness was further explored. The research results indicate that nickel as a non-carbide-forming element does not alter the type and total amount of carbide precipitation at equilibrium, but it can dissolve into the matrix and form substitutional lattice distortions with Fe atoms, promoting the dispersion of secondary carbides during the tempering process. This mechanism can reduce intergranular precipitation and inhibit grain boundary embrittlement, thereby improving toughness. However, it can also accelerate the precipitation, aggregation, and growth of secondary carbides during prolonged tempering, which deteriorates the high-temperature anti-softening properties of die steels. The role of Ni has been revealed through thermodynamic and kinetic calculations. The results show that Ni significantly enhances the diffusion coefficient of Cr atoms in the face centered cubic (fcc) Fe matrix during tempering and also improves the phase transition driving force of various precipitates. This work provides new insights into the mechanism of Ni in hot-working die steels, and can provide guidance for designing novel hot-working die steel

Recent Progress in Innate Immune Responses to Enterovirus A71 and Viral Evasion Strategies

Enterovirus A71 (EV-A71) is a major pathogen causing hand, foot, and mouth disease (HFMD) in children worldwide. It can lead to severe gastrointestinal, pulmonary, and neurological complications. The innate immune system, which rapidly detects pathogens via pathogen-associated molecular patterns or pathogen-encoded effectors, serves as the first defensive line against EV-A71 infection. Concurrently, the virus has developed various sophisticated strategies to evade host antiviral responses and establish productive infection. Thus, the virus–host interactions and conflicts, as well as the ability to govern biological events at this first line of defense, contribute significantly to the pathogenesis and outcomes of EV-A71 infection. In this review, we update recent progress on host innate immune responses to EV-A71 infection. In addition, we discuss the underlying strategies employed by EV-A71 to escape host innate immune responses. A better understanding of the interplay between EV-A71 and host innate immunity may unravel potential antiviral targets, as well as strategies that can improve patient outcomes