Variations in visual factors such as viewpoint, pose, illumination and background, are usually viewed as important challenges in person re-identification (re-ID). In spite of acknowledging these ...factors to be influential, quantitative studies on how they affect a re-ID system are still lacking. To derive insights in this scientific campaign, this paper makes an early attempt in studying a particular factor, viewpoint. We narrow the viewpoint problem down to the pedestrian rotation angle to obtain focused conclusions. In this regard, this paper makes two contributions to the community. First, we introduce a large-scale synthetic data engine, PersonX. Composed of hand-crafted 3D person models, the salient characteristic of this engine is "controllable". That is, we are able to synthesize pedestrians by setting the visual variables to arbitrary values. Second, on the 3D data engine, we quantitatively analyze the influence of pedestrian rotation angle on re-ID accuracy. Comprehensively, the person rotation angles are precisely customized from 0 to 360, allowing us to investigate its effect on the training, query, and gallery sets. Extensive experiment helps us have a deeper understanding of the fundamental problems in person re-ID. Our research also provides useful insights for dataset building and future practical usage, e.g., a person of a side view makes a better query.
Competing geodynamic models, such as rigid-block extrusion, continuous deformation, and the mid-lower crustal flow, have been proposed to describe the growth and expansion of eastern Tibet. However, ...the dynamic processes responsible for plateau evolution and deformation remain poorly understood partly due to resolution limitations of previous models of lithospheric structure. On the basis of joint inversion of Rayleigh wave dispersion and receiver functions using data from a newly deployed seismic array, we have obtained a high-resolution 3D image that reveals the distribution of low-velocity zones (LVZs) with unprecedented clarity. The prominent feature of our model is two low-velocity channels that bound major strike-slip faults in SE Tibet and wrap around the Eastern Himalaya Syntaxis, consistent with the clockwise movement of crustal material in this region. Most large earthquakes in this region occurred in the boundaries of the LVZs. We propose that ductile flow within these channels, in addition to shear motion along strike-slip faults, played a significant role in accommodating intensive lithospheric deformation during the eastward expansion of Tibet in the Cenozoic.
•Image two channels of low-velocity zones with unprecedented resolution.•The two channels bound main strike-slip faults of SE Tibet.•The two channels wrap around the Eastern Himalaya Syntaxis.•Large earthquakes occurred at the edge of the two channels.•Deformation of SE Tibet is accommodated by both ductile flow and shearing.
The five largest rivers in East and Southeast Asia (Yellow, Yangtze, Pearl, Red and Mekong) are important contributors of terrigenous sediment to the western Pacific Ocean. Although they have ...annually delivered ~
2000
×
10
9
kg of sediment to the ocean since 1000
yr BP, they presently contribute only ~
600
×
10
9
kg/yr, which is reverting to a level typical of the relatively undisturbed watersheds before the rise in human activities in East and Southeast Asia at 2000
yr BP. During the most recent decades flow regulation by dams and sediment entrapment by reservoirs, as well as human-influenced soil erosion in the river basins, have sharply reduced the sediment delivered from the large river basins to the ocean. We constructed a time series of data on annual water discharges and sediment fluxes from these large rivers to the western Pacific Ocean covering the period 1950–2008. These data indicate that the short-term (interannual scale) variation of sediment flux is dominated by natural climatic oscillations such as the El Niño/La Niña cycle and that anthropogenic causes involving dams and land use control the long-term (decadal scale) decrease in sediment flux to the ocean. In contrast to the relatively slow historical increase in sediment flux during the period 2000–1000
yr BP, the recent sediment flux has been decreased at an accelerating rate over centennial scales. The alterations of these large river systems by both natural and anthropogenic forcing present severe environmental challenges in the coastal ocean, including the sinking of deltas and declines in coastal wetland areas due to the decreasing sediment supply. Our work thus provides a regional perspective on the large river-derived sediment flux to the ocean over millennial and decadal scales, which will be important for understanding and managing the present and future trends of delivery of terrigenous sediment to the ocean in the context of global change.
► We reviewed the sediment flux from major Asian rivers to the western Pacific Ocean over millennial and centennial scales. ► Both the millennial increase in sediment flux and the centennial decrease are primarily dominated by human interventions. ► Interannual variation of sediment flux is dominated by natural climatic oscillations. ► Anthropogenic causes involving dams and land use control the decadal decrease in sediment flux to the ocean. ► The natural and anthropogenic alteration of large river systems present severe environmental challenges in the coastal ocean.
Single-cell RNA sequencing (scRNA-seq) technologies allow researchers to uncover the biological states of a single cell at high resolution. For computational efficiency and easy visualization, ...dimensionality reduction is necessary to capture gene expression patterns in low-dimensional space. Here we propose an ensemble method for simultaneous dimensionality reduction and feature gene extraction (EDGE) of scRNA-seq data. Different from existing dimensionality reduction techniques, the proposed method implements an ensemble learning scheme that utilizes massive weak learners for an accurate similarity search. Based on the similarity matrix constructed by those weak learners, the low-dimensional embedding of the data is estimated and optimized through spectral embedding and stochastic gradient descent. Comprehensive simulation and empirical studies show that EDGE is well suited for searching for meaningful organization of cells, detecting rare cell types, and identifying essential feature genes associated with certain cell types.
Understanding the Mesozoic–Cenozoic tectonic evolution of the North China Craton (NCC) and the NE Tibetan Plateau (TP) requires detailed knowledge of the lithospheric structure. Using dense regional ...networks and temporary deployments as well as updated reference models, we obtain the crust and upper mantle structure to 120km depth. Our tomographic results show several major features, which have particular implications for the Weihe–Shanxi rift system (WSRS), deformation of the NE TP, and lithospheric evolution of the NCC. Beneath the WSRS, the crust gradually thickens from south to north, the lithospheric mantle gradually becomes slower, and the mid-lower crustal velocities are lower in the Weihe Rift, where rifting of the WSRS initiated. We suggest that along-strike variations of the lithospheric structures of the WSRS have played an important role in its multistage evolution. A low-velocity zone (LVZ) in the mid-crust beneath the Qilian Orogen is characterized by relatively higher velocities compared to LVZs in other parts of the TP. Thus, coherent lithospheric deformation may occur due to the high viscosity of the LVZ during early plateau growth, causing strong anisotropy to develop. The western NCC (including the Ordos Block and part of the Alashan Block) shows a high-velocity cratonic root extending to the base of our model. In contrast, the lithosphere of the eastern NCC appears to have been completely modified during the Mesozoic through Cenozoic and presents a thin lithosphere of relatively low velocities underlain by hot asthenosphere. We observed significant upper-mantle heterogeneities in the NCC, which may reflect its diachronous lithospheric modification.
•Use of unprecedented amount of seismic data, including dense regional networks.•Combine ambient noise and earthquake data from recent national models.•The initiation of the Weihe–Shanxi Rift is controlled by the deformation of the Tibetan Plateau.•Isolated mid-crust low velocity zone in Qilian Shan may reconcile vertically coherent deformation model.•Significant upper-mantle heterogeneities are revealed in North China.
Accurate quantification of the coexistence of adsorbed and free gas content holds the utmost significance for estimating gas-in-place resources and predicting gas production dynamics. In this study, ...we conducted real-time isothermal adsorption experiments and NMR fluid monitoring on stress-confining core samples, from the Zhengzhuang Block's No.3 coal seam in the southern Qinshui Basin. Our focus was on assessing multi-phase methane gas contents within coal under various pressure and temperature (P/T) conditions. By integrating experimental findings with adsorption potential theory and the SDR adsorption model, we developed comprehensive models for adsorbed, free, and total gas contents as functions of P/T and water/gas volume saturation. Utilizing these models, we predicted vertical variations in adsorbed and free gas contents within the coal seam. Our results revealed that the interplay between positive reservoir pressure effects and adverse reservoir temperature effects influenced both adsorbed and free methane gases. With increasing burial depth, the influence of pressure on adsorbed gas diminished, while temperature effects became more pronounced. Conversely, free gas content responded noticeably to reservoir pressure, with temperature exerting a marginal influence. Additionally, we performed a numerical simulation to reconstruct the thermal history, burial trajectory, and evolution of reservoir pressure for the No.3 coal seam. The simulation results served as foundational data for understanding the evolution of free and adsorbed gas contents across different geological epochs within the in-situ reservoir. Our findings unveiled a four-stage evolutionary progression in both adsorbed and free gas contents, correlating with the uplift and subsidence of the coal seam. In conclusion, our study provides a conceptual model elucidating the intricate, deep-time evolution process and mechanisms governing the occurrence of multiphase gases across distinct geological epochs. The implications of this research are crucial for accurately evaluating gas-in-place resources and guiding the exploration and development of deep coalbed methane resources.
Recent evidence shows that programs targeting the socio-emotional dimensions of entrepreneurship-e.g., resilience, personal initiative, and empathy-are more highly correlated with success along with ...key business metrics, such as sales and survival, than programs with a narrow, technical bent-e.g., accounting and finance. We argue that programs designed to foster socio-emotional skills are effective in improving entrepreneurship outcomes because they improve the students' ability to regulate their emotions. They enhance the individuals' disposition to make more measured, rational decisions. We test this hypothesis studying a randomized controlled trial (RCT, RCT ID: AEARCTR-0000916) of an entrepreneurship program in Chile. We combine administrative data, surveys, and neuro-psychological data from lab-in-the-field measurements. A key methodological contribution of this study is the use of the electroencephalogram (EEG) to quantify the impact of emotional responses. We find that the program has a positive and significant impact on educational outcomes and, in line with the findings of other studies in the literature, we find no impact on self-reported measures of socio-emotional skills (e.g., grit and locus of control) and creativity. Our novel insight comes from the finding that the program has a significant impact on neurophysiological markers, decreasing arousal (a proxy of alertness), valence (a proxy for withdrawal from or approachability to an event or stimuli), and neuro-psychological changes to negative stimuli.
Lysosomal degradation of cytoplasmic components by autophagy is essential for cellular survival and homeostasis under nutrient-deprived conditions. Acute regulation of autophagy by nutrient-sensing ...kinases is well defined, but longer-term transcriptional regulation is relatively unknown. Here we show that the fed-state sensing nuclear receptor farnesoid X receptor (FXR) and the fasting transcriptional activator cAMP response element-binding protein (CREB) coordinately regulate the hepatic autophagy gene network. Pharmacological activation of FXR repressed many autophagy genes and inhibited autophagy even in fasted mice, and feeding-mediated inhibition of macroautophagy was attenuated in FXR-knockout mice. From mouse liver chromatin immunoprecipitation and high-throughput sequencing data, FXR and CREB binding peaks were detected at 178 and 112 genes, respectively, out of 230 autophagy-related genes, and 78 genes showed shared binding, mostly in their promoter regions. CREB promoted autophagic degradation of lipids, or lipophagy, under nutrient-deprived conditions, and FXR inhibited this response. Mechanistically, CREB upregulated autophagy genes, including Atg7, Ulk1 and Tfeb, by recruiting the coactivator CRTC2. After feeding or pharmacological activation, FXR trans-repressed these genes by disrupting the functional CREB-CRTC2 complex. This study identifies the new FXR-CREB axis as a key physiological switch regulating autophagy, resulting in sustained nutrient regulation of autophagy during feeding/fasting cycles.
Abstract
Contrary to the common belief that the light-induced halide ion segregation in a mixed halide alloy occurs within the illuminated area, we find that the Br ions released by light are ...expelled from the illuminated area, which generates a macro/mesoscopic size anion ring surrounding the illuminated area, exhibiting a photoluminescence ring. This intriguing phenomenon can be explained as resulting from two counter-balancing effects: the outward diffusion of the light-induced free Br ions and the Coulombic force between the anion deficit and surplus region. Right after removing the illumination, the macro/mesoscopic scale ion displacement results in a built-in voltage of about 0.4 V between the ring and the center. Then, the displaced anions return to the illuminated area, and the restoring force leads to a damped ultra-low-frequency oscillatory ion motion, with a period of about 20–30 h and lasting over 100 h. This finding may be the first observation of an ionic plasma oscillation in solids. Our understanding and controlling the “ion segregation” demonstrate that it is possible to turn this commonly viewed “adverse phenomenon” into novel electronic applications, such as ionic patterning, self-destructive memory, and energy storage.
PDF
