4D Imaging and Diffraction Dynamics of Single-Particle Phase Transition in Heterogeneous Ensembles

In this Letter, we introduce conical-scanning dark-field imaging in four-dimensional (4D) ultrafast electron microscopy to visualize single-particle dynamics of a polycrystalline ensemble undergoing phase transitions. Specifically, the ultrafast metal–insulator phase transition of vanadium dioxide is induced using laser excitation and followed by taking electron-pulsed, time-resolved images and diffraction patterns. The single-particle selectivity is achieved by identifying the origin of all constituent Bragg spots on Debye–Scherrer rings from the ensemble. Orientation mapping and dynamic scattering simulation of the electron diffraction patterns in the monoclinic and tetragonal phase during the transition confirm the observed behavior of Bragg spots change with time. We found that the threshold temperature for phase recovery increases with increasing particle sizes and we quantified the observation through a theoretical model developed for single-particle phase transitions. The reported methodology of conical scanning, orientation mapping in 4D imaging promises to be powerful for heterogeneous ensemble, as it enables imaging and diffraction at a given time with a full archive of structural information for each particle, for example, size, morphology, and orientation while minimizing radiation damage to the specimen

Development of Ecological Fishery in Poyang Lake Area

Through in-depth analysis on history and current situations of fishery development in Poyang Lake area, this paper presents location, resource and environment advantages in development of ecological fishery. According to orientation of leading functions, Poyang Lake can be divided into breeding development, capture operation, enhancement protection and ecological rehabilitation functional zones. In accordance with industrial foundation and ecological advantages of cities and counties in Poyang Lake, it determines the reasonable distribution of 8 leading industries: river crabs, shrimps (Procambarus clarkia), eels, Pengze crucian carp, Siniperca chuatsi, Channa argus, Ietalurus Punetaus, and pearl. On the basis of systematically summing up exploration experience, it comes up with the development path “ecology oriented fishery and industrialization oriented ecological fishery” for ecological fishery in Poyang Lake area. It proposes a series of key technological measures, including reducing fertilizer and drugs, increasing output and benefits, low consumption and emission, high quality and safety, and standardization, to realize a benign cycle of “cost saving, benefit increasing, quality improving and low carbon” and the multi-win objective of coordination between ecology, economy and society

Mechanical behaviors and damage characteristics of excavated jointed rocks within 3D printed structures

The presence of structural planes in rock masses reduces their mechanical properties and greatly affects their failure mode, resulting in physical and mechanical anisotropy. This study investigated the mechanical behaviors and damage characteristics of excavated jointed rocks in three-dimensional (3D) printed structures. A digital fracture network model based on the fractal principle was also developed to simulate a complex and rough network of fractures. Using 3D printing technology, rock specimens within a single rough structure surface, different dip angles, and rough fracture network models were established, considering different excavation sizes. Uniaxial compression was performed experimentally to investigate the mechanical response of rock masses. The failure processes of the jointed specimens were analyzed based on the digital image correlation (DIC) technique. The uniaxial compressive strength and elastic modulus were compared considering different excavation sizes. The results show that the geometric characteristics of the joints significantly influence the strength and failure mode of the rock mass. The strength of the layered rock mass shows a significant linear correlation with increasing excavation sizes. This research could provide a reference for studying the mechanical behavior of jointed rock masses using 3D printing technology

Review of current ZT > 1 thermoelectric sulfides

Thermoelectrics has played a fascinating role in the developments of direct energy conversion technologies. Over the past decade, sulfur-based thermoelectric materials have been significantly advanced in optimizing electrical and thermal transport due to their similarities in chemical and structural properties with tellurides and selenides. This review provides research progress on metal sulfides, particularly focuses on materials exhibiting high thermoelectric figure of merit (ZT > 1.0). It highlights the potential compounds, e.g. CuS, SnS, PbS based, and polysulfides. Great strategies of superionic conducting, band configuration tuning, high-entropy alloying, and anomalous harmonic scattering are try to demonstrate the performance-improved mechanisms for thermoelectric sulfides. In addition, some common synthesis recipes are briefly introduced, and thereby making potential candidates as excellent alternatives for producing thermoelectric power generators in the mid temperature. Key outcomes along with how to further improve the thermoelectric performance and promote its scale-up applications are also outlined at the end

The Experience and Development of the Treatment Technology of Municipal Solid Waste Leachate in China

This paper reviews the characteristics of leachate produced from municipal solid waste landfills, incineration plants, transfer stations, and food waste anaerobic fermentation plants. In addition, the development of the leachate treatment technology used in China is investigated. The development period of leachate treatment technology in China can be divided into five stages: the early 1990s with simple biological treatment, the mid-to-late 1990s with ammonia stripping + anaerobic + aerobic treatment, from 2000 to 2008 with a two-stage disc tube reverse osmosis (DT-RO) process, from 2008 to 2015 with an anaerobic + aerobic + advanced treatment process, and from 2015 until the present with a diversified and full quantitative process. Furthermore, under the requirements of ecological environmental protection and “dual carbon” development concepts, this paper advises the future development trend of Chinese municipal solid waste leachate, which will enact more scientific emission standards and local standards, become inevitable for the green ecology of the technical route, be more professional and intelligent for construction and operation, and diversify resource utilization of the treatment facilities process

A c-di-GMP signaling module controls responses to iron in Pseudomonas aeruginosa

Abstract Cyclic dimeric guanosine monophosphate (c-di-GMP) serves as a bacterial second messenger that modulates various processes including biofilm formation, motility, and host-microbe symbiosis. Numerous studies have conducted comprehensive analysis of c-di-GMP. However, the mechanisms by which certain environmental signals such as iron control intracellular c-di-GMP levels are unclear. Here, we show that iron regulates c-di-GMP levels in Pseudomonas aeruginosa by modulating the interaction between an iron-sensing protein, IsmP, and a diguanylate cyclase, ImcA. Binding of iron to the CHASE4 domain of IsmP inhibits the IsmP-ImcA interaction, which leads to increased c-di-GMP synthesis by ImcA, thus promoting biofilm formation and reducing bacterial motility. Structural characterization of the apo-CHASE4 domain and its binding to iron allows us to pinpoint residues defining its specificity. In addition, the cryo-electron microscopy structure of ImcA in complex with a c-di-GMP analog (GMPCPP) suggests a unique conformation in which the compound binds to the catalytic pockets and to the membrane-proximal side located at the cytoplasm. Thus, our results indicate that a CHASE4 domain directly senses iron and modulates the crosstalk between c-di-GMP metabolic enzymes

The Experience and Development of the Treatment Technology of Municipal Solid Waste Leachate in China

This paper reviews the characteristics of leachate produced from municipal solid waste landfills, incineration plants, transfer stations, and food waste anaerobic fermentation plants. In addition, the development of the leachate treatment technology used in China is investigated. The development period of leachate treatment technology in China can be divided into five stages: the early 1990s with simple biological treatment, the mid-to-late 1990s with ammonia stripping + anaerobic + aerobic treatment, from 2000 to 2008 with a two-stage disc tube reverse osmosis (DT-RO) process, from 2008 to 2015 with an anaerobic + aerobic + advanced treatment process, and from 2015 until the present with a diversified and full quantitative process. Furthermore, under the requirements of ecological environmental protection and “dual carbon” development concepts, this paper advises the future development trend of Chinese municipal solid waste leachate, which will enact more scientific emission standards and local standards, become inevitable for the green ecology of the technical route, be more professional and intelligent for construction and operation, and diversify resource utilization of the treatment facilities process

Intra-Tumoral Heterogeneity of HER2, FGFR2, cMET and ATM in Gastric Cancer: Optimizing Personalized Healthcare through Innovative Pathological and Statistical Analysis.

Current drug development efforts on gastric cancer are directed against several molecular targets driving the growth of this neoplasm. Intra-tumoral biomarker heterogeneity however, commonly observed in gastric cancer, could lead to biased selection of patients. MET, ATM, FGFR2, and HER2 were profiled on gastric cancer biopsy samples. An innovative pathological assessment was performed through scoring of individual biopsies against whole biopsies from a single patient to enable heterogeneity evaluation. Following this, false negative risks for each biomarker were estimated in silico. 166 gastric cancer cases with multiple biopsies from single patients were collected from Shanghai Renji Hospital. Following pre-set criteria, 56 ~ 78% cases showed low, 15 ~ 35% showed medium and 0 ~ 11% showed high heterogeneity within the biomarkers profiled. If 3 biopsies were collected from a single patient, the false negative risk for detection of the biomarkers was close to 5% (exception for FGFR2: 12.2%). When 6 biopsies were collected, the false negative risk approached 0%. Our study demonstrates the benefit of multiple biopsy sampling when considering personalized healthcare biomarker strategy, and provides an example to address the challenge of intra-tumoral biomarker heterogeneity using alternative pathological assessment and statistical methods