The Impacts of Collective Action in Common-Pool Resources ——Evidence From the Field of Grassland Use

The deterioration of common-pool resources is a serious issue faced by over the world now. How to manage public resources sustainably is extremely urgent. Collective action plays an important role in the sustainable management of common-pool resources. It creates a common goal that makes resource users not only concern their individual interests, but also the collective interests, in order to avoid the common-pool resource dilemma. The extent of collective interests that resource users concern affects their decisions in collective action, which further impacts the sustainable use of common-pool resources. We use a grazing experiment to observe and measure collective action. Combining the experimental data with the data in the real world, we find that resource users with more collective interests in collective action have higher grassland quality and less grazing livestock. Moreover, we use principal components analysis measuring collective action indicators to verify the robustness of these findings. A mechanism analysis is conducted to explain why collective action has positive effects on grassland restoration. Heterogeneity analysis examines the different impacts of collective actions with various natural endowments and individual characteristics. This study proves that collective action has positive impacts on the sustainable management of common-pool resources, which provides an empirical evidence on sustainable use of public natural resources through community-based natural resource management

DEVELOPMENT AND APPLICATIONS OF FEATURE-GUIDED CARDIAC MOTION ESTIMATION METHODS FOR 4D CARDIAC PET

The aim of this dissertation research is to develop, implement and evaluate methods to extract useful information about cardiac motion and myocardial contractility from 4D cardiac PET images with much improved image quality. First, to reduce the influence of respiratory motion and improve the quality of cardiac PET images used in motion estimation, data-driven respiratory gating methods are proposed to allow accurate extraction of respiratory motion signal from the list-mode data. Time-of-flight PET information is incorporated into respiratory signal extraction, and background correction method is developed to improve the quality and accuracy of the extracted respiratory signal. The methods were applied and evaluated using clinical list-mode cardiac PET data. With improved image quality, anatomical feature such as papillary muscles and the interventricular sulcus become increasingly detectable in gated cardiac PET images. For more accurate cardiac motion estimation, these anatomical features in human heart were extracted and used in combination with a priori knowledge of cardiac function to guide the cardiac motion estimation process. Initial estimates of the cardiac motion vector field were obtained based on the motion of the features for the traditional optical-flow algorithm. For further improvement, motion of the anatomical feature was used as additional constraint in the motion estimation algorithm to reduce the effect of the classical aperture problem. Different from previous cardiac motion extraction and estimation studies that only provide qualitative evaluation of the motion estimation results due to unavailability of ground truth for clinical cardiac datasets, this study employed simulation data from a realistic digital phantom with known cardiac motion for both qualitative and quantitative evaluation. Motion estimation results from simulation data indicate the feature-based cardiac motion estimation method is able to improve the accuracy of the cardiac motion field estimates, especially for motion components parallel to edges and therefore difficult to estimate using the conventional optical-flow based method. The proposed research will allow PET imaging to provide unprecedented cardiac motion information in addition to its functional information thus improving diagnosis of cardiac diseases including perfusion and motion abnormalities, and patient care with reduced cost. Also, more accurate estimation of cardiac motion will help to further improve the quality of 4D cardiac PET imaging with cardiac motion compensation

A model local interpretation routine for deep learning based radio galaxy classification

Radio galaxy morphological classification is one of the critical steps when producing source catalogues for large-scale radio continuum surveys. While many recent studies attempted to classify source radio morphology from survey image data using deep learning algorithms (i.e., Convolutional Neural Networks), they concentrated on model robustness most time. It is unclear whether a model similarly makes predictions as radio astronomers did. In this work, we used Local Interpretable Model-agnostic Explanation (LIME), an state-of-the-art eXplainable Artificial Intelligence (XAI) technique to explain model prediction behaviour and thus examine the hypothesis in a proof-of-concept manner. In what follows, we describe how \textbf{LIME} generally works and early results about how it helped explain predictions of a radio galaxy classification model using this technique.Comment: 4 pages, 1 figure, accepted summary paper for URSI GASS 2023 J0

Sustainable utilization of bauxite residue (Red Mud) as a road material in pavements: A critical review

Sustainable utilization of the bauxite residue (red mud) generated from the alumina refining has recently increased due to increased environmental concerns because of its high alkalinity and problematic pollutants when placed in landfills. This paper attempts to review recent research findings of utilizing red mud as a road material in pavement structures in literature, including road bases and asphalt mixtures. Previous laboratory investigations indicated that red mud is feasible to be used as a raw material in road bases with satisfactory unconfined compressive strength (UCS), frost resistance and durability performance, but their durability during the service life of the pavement is still unclear. The incorporation of red mud in asphalt mastics was found to be able to improve its stiffness, such as softening point, complex modulus, and viscosity. In terms of asphalt mixtures, replacing limestone filler in mixtures by red mud resulted in some positive effects on mechanical behaviors, high bulk density and good rutting resistance. However, the moisture susceptibility and raveling resistance of asphalt mixtures became relatively worse because of the addition of red mud. Referring to this overview, it is necessary to qualify the long-term service performance of road base materials prepared with red mud by using laboratory accelerating evaluation or road trials. For asphalt mixtures prepared with red mud, how to improve durability, in particular moisture resistance, will be a future research focus. In addition, the influence of red mud on cracking resistance at low temperature, fatigue properties and long-term durability of asphalt mixtures is still needed to be further explored

The Influence of Dietary Gallic Acid on Growth Performance and Plasma Antioxidant Status of High and Low Weaning Weight Piglets.

peer reviewedThis study evaluated the effects of dietary gallic acid (GA) on growth performance, diarrhea incidence and plasma antioxidant status of weaned piglets regardless of whether weaning weight was high or low. A total of 120 weaned piglets were randomly allocated to four treatments in a 42-day experiment with a 2 × 2 factorial treatment arrangement comparing different weaning weights (high weight (HW) or low weight (LW), 8.49 ± 0.18 kg vs. 5.45 ± 0.13 kg) and dietary treatment (without supplementation (CT) or with supplementation of 400 mg/kg of GA). The results showed that HW piglets exhibited better growth performance and plasma antioxidant capacity. Piglets supplemented with GA had higher body weight (BW) on day 42 and average daily gain (ADG) from day 0 to 42 compared to the control piglets, which is mainly attributed to the specific improvement on BW and ADG of LW piglets by the supplementation of GA. The decreased values of diarrhea incidence were seen in piglets fed GA, more particularly in LW piglets. In addition, dietary GA numerically reduced malondialdehyde (MDA) content in plasma of LW piglets. In conclusion, our study suggests that dietary GA may especially improve the growth and health in LW weaned piglets

Polyoxometalate-supported Pd nanoparticles as efficient catalysts for the direct synthesis of hydrogen peroxide in the absence of acid or halide promoters

A Keggin-type polyoxometalate (Cs1.5H1.5PW12O40)-supported Pd catalyst is efficient for the direct synthesis of H2O2 from H-2 and O-2 in the absence of any acid or halide additives under atmospheric pressure.NSFC [20625310, 20773099, 20873110]; National Basic Research Program of China [2005CB221408]; Program for New Century Excellent Talents in Fujian Provinc

NiO-polyoxometalate nanocomposites as efficient catalysts for the oxidative dehydrogenation of propane and isobutane

Novel nanocomposites of NiO and polyoxometalate (Cs2.5H0.5PMo12O40) with particle sizes in the range of 5-10 nm showed exceptional oxygen and ammonia adsorption capabilities, and the nanocomposites catalyzed the oxidative dehydrogenation of propane and isobutane efficiently under mild conditions.NSFC [20625310, 20773099, 20873110]; National Basic Research Program of China [2005CB221408]; Program for New Century Excellent Talents in Fujian Provinc

Defect-induced helicity-dependent terahertz emission in Dirac semimetal PtTe2 thin films

Nonlinear transport enabled by symmetry breaking in quantum materials has aroused considerable interest in condensed matter physics and interdisciplinary electronics. However, the nonlinear optical response in centrosymmetric Dirac semimetals via the defect engineering has remained highly challenging. Here, we observe the helicity-dependent terahertz (THz) emission in Dirac semimetal PtTe2 thin films via circular photogalvanic effect (CPGE) under normal incidence. This is activated by artificially controllable out-of-plane Te-vacancy defect gradient, which is unambiguously evidenced by the electron ptychography. The defect gradient lowers the symmetry, which not only induces the band spin splitting, but also generates the giant Berry curvature dipole (BCD) responsible for the CPGE. Such BCD-induced helicity-dependent THz emission can be manipulated by the Te-vacancy defect concentration. Furthermore, temperature evolution of the THz emission features the minimum of the THz amplitude due to the carrier compensation. Our work provides a universal strategy for symmetry breaking in centrosymmetric Dirac materials for efficient nonlinear transport and facilitates the promising device applications in integrated optoelectronics and spintronics.Comment: 27 pages, 5 figure