A Red-Emission Fluorescent Probe for Intracellular Biothiols and Hydrogen Sulfide Imaging in Living Cells.

This research centers on the development and synthesis of a longwave fluorescence probe, labeled as 60T, designed for the simultaneous detection of hydrogen sulfide, cysteine/homocysteine, and glutathione. The probe showcases a swift response, good linearity range, and heightened sensitivity, boasting that the detection limits of the probe for Cys, Hcy, GSH and H2S were 0.140, 0.202, 0.259 and 0.396 µM, respectively. Notably, its efficacy in monitoring thiol status changes in live MCF-7 cells is underscored by a substantial decrease in fluorescence intensity upon exposure to the thiol trapping reagent, N-ethyl maleimide (NEM). With an impressive red emission signal at 630 nm and a substantial Stokes shift of 80 nm, this probe exhibits remarkable sensitivity and selectivity for biothiols and H2S, indicating promising applications in the diagnosis and surgical navigation of relevant cancers.

Recent Progress in Testing and Characterization of Hardenability of Aluminum Alloys: A Review.

In this paper, the progress of the test methods and characterization approaches of aluminum alloys hardenability was reviewed in detail. The test method mainly included the traditional end-quenching method and the modified method. While the characterization approaches of alloy hardenability consist mainly of ageing hardness curves, solid solution conductivity curves, ageing tensile curves, time temperature transformation (TTT) curves, time temperature properties (TTP) curves, continuous cooling transformation (CCT) curves, and advanced theoretical derivation method have appeared in recent years. The hardenability testing equipment for different tested samples with different material natures, engineering applications properties, and measurement sizes was introduced. Meanwhile, the improvement programmed proposed for shortcomings in the traditional hardenability testing process and the current deficiencies during the overall hardenability testing process were also presented. In addition, the influence factors from the view of composition design applied to the hardenability behaviors of Aluminum alloys were summarized. Among them, the combined addition of micro-alloying elements is considered to be a better method for improving the hardenability of high-strength aluminum alloys.

Heterogeneous effects of China's low-carbon city pilots policy.

Global south countries, including China, have faced a challenging dilemma of reducing carbon emissions while maintaining rapid economic growth. The low-carbon city pilots (LCCPs) policy in China is a demonstration of how state power intervenes and commands national low-carbon development through voluntary policy tools. Our study, based on panel data of 331 cities from 2005 to 2019, evaluates the policy effect of all three batches of LCCPs and presents an analysis of time-varying effects through batch decomposition and synthetic difference-in-difference models. The study found that implementing low-carbon policies can significantly reduce total carbon emissions and carbon emissions per capita. However, the reduction in carbon emissions per unit of GDP is insignificant, and the policy effect varies according to the batches and their characteristics. The reduction effects in the first and second batches, as well as the insignificance or even increasing effects of the third batch, may be due to carbon leakage between different batches of LCCPs. Overall, this research provides novel and quantitative evidence on low-carbon development in China, making theoretical and empirical contributions to the field, and expanding econometric assessment methods to evaluate the effectiveness of environmental and climate change policies.

2D Material and Perovskite Heterostructure for Optoelectronic Applications.

Optoelectronic devices are key building blocks for sustainable energy, imaging applications, and optical communications in modern society. Two-dimensional materials and perovskites have been considered promising candidates in this research area due to their fascinating material properties. Despite the significant progress achieved in the past decades, challenges still remain to further improve the performance of devices based on 2D materials or perovskites and to solve stability issues for their reliability. Recently, a novel concept of 2D material/perovskite heterostructure has demonstrated remarkable achievements by taking advantage of both materials. The diverse fabrication techniques and large families of 2D materials and perovskites open up great opportunities for structure modification, interface engineering, and composition tuning in state-of-the-art optoelectronics. In this review, we present comprehensive information on the synthesis methods, material properties of 2D materials and perovskites, and the research progress of optoelectronic devices, particularly solar cells and photodetectors which are based on 2D materials, perovskites, and 2D material/perovskite heterostructures with future perspectives.

Is Ecological Birdwatching Tourism a More Effective Way to Transform the Value of Ecosystem Services?-A Case Study of Birdwatching Destinations in Mingxi County, China.

Ecological birdwatching tourism is an ecological product and an essential part of ecotourism, and the realization of its recreation value is crucial for improving human well-being, and realization of the local benefits of ecosystem services for areas focused on biodiversity conservation, especially in bird species. In this study, we use travel cost interval analysis, one of the travel cost derived models featuring more easily satisfied assumptions and less limited data, to evaluate the recreation value of the ecological bird-watching tourism destination, and compare it with the general ecotourism, of Mingxi County destination in China. The results show that, firstly, the per capita recreation value of eco-birdwatching is 3.9 times that of general eco-tourism, its per capita social benefit is three times that of general eco-tourism, and its per capita economic benefit is 4.5 times that of general eco-tourism. Secondly, compared with general ecotourists, the per capita travel costs of eco-birdwatchers are higher, and there were significant statistical differences in the expenses for catering, tickets, shopping, opportunity cost, and total travel expenses between these two groups. Thirdly, in comparison with general ecotourists, the marginal cost of an individual eco-birdwatcher is higher, and the travel intention of an eco-birdwatcher is more robust at the same cost level. The price of a single eco-birdwatcher is higher under the same travel intention demand level. In short, the ecological bird-watching industry has a higher marginal value than general eco-tourism and has higher social, economic, and ecological benefits, bringing a higher level of development for the local tourism industry.

Tunable and Transferable Diamond Membranes for Integrated Quantum Technologies.

Color centers in diamond are widely explored as qubits in quantum technologies. However, challenges remain in the effective and efficient integration of these diamond-hosted qubits in device heterostructures. Here, nanoscale-thick uniform diamond membranes are synthesized via "smart-cut" and isotopically (12C) purified overgrowth. These membranes have tunable thicknesses (demonstrated 50 to 250 nm), are deterministically transferable, have bilaterally atomically flat surfaces (Rq ≤ 0.3 nm), and bulk-diamond-like crystallinity. Color centers are synthesized via both implantation and in situ overgrowth incorporation. Within 110-nm-thick membranes, individual germanium-vacancy (GeV-) centers exhibit stable photoluminescence at 5.4 K and average optical transition line widths as low as 125 MHz. The room temperature spin coherence of individual nitrogen-vacancy (NV-) centers shows Ramsey spin dephasing times (T2*) and Hahn echo times (T2) as long as 150 and 400 µs, respectively. This platform enables the straightforward integration of diamond membranes that host coherent color centers into quantum technologies.

Development of a Weighted Barite-Free Formate Drilling Mud for Well Construction under Complicated Conditions.

Construction of oil and gas wells at offshore fields often involves high formation pressure and the presence of swellable clay rocks in the section. In addition, productivity preservation is also an important aspect. For this purpose, it is necessary to reduce the solids content of the drilling mud. The purpose of this work is to develop, improve, and study compositions of weighted drilling muds with low content of solids, on the basis of organic salts of alkali metals and polymers for the construction of wells prone to rock swelling and/or cavings, as well as drilling fluids for drilling-in the formation. In order to achieve the set goal the following is required: Analysis of existing drilling muds of higher density for drilling wells in unstable rock intervals and for drilling in the productive formation; analysis of experience in using drilling systems on the formic acid salts base and substantiation of requirements for flushing fluids during well construction; development and investigation of drilling mud compositions on the formate base; and the evaluation of inhibiting effect of systems containing organic salts, polymer reagents, and calcium carbonate on clay samples. The developed drilling mud is characterized by a high inhibiting ability that allows minimized mud-weighting by the natural solid phase. This reduces the volume of prepared mud and facilitates the regulation of its properties by reducing the dispersion of drilled cuttings; it eliminates problems related to hydration and the swelling of active clay rocks; and stabilizes unstable argillites prone to caving. The low solids content, low filtration rates, and inhibitory nature of the mud allows high stability of the rheological properties of the mud, and preserves oil and gas reservoir productivity under conditions of elevated formation pressure.

Revealing Ionic Signal Enhancement with Probe Grafting Density on the Outer Surface of Nanochannels.

Probe-modified nanopores/nanochannels are one of the most advanced sensors because the probes interact strongly with ions and targets in nanoconfinement and create a sensitive and selective ionic signal. Recently, ionic signals have been demonstrated to be sensitive to the probe-target interaction on the outer surface of nanopores/nanochannels, which can offer more open space for target recognition and signal conversion than nanoconfined cavities. To enhance the ionic signal, we investigated the effect of grafting density, a critical parameter of the sensing interface, of the probe on the outer surface of nanochannels on the change rate of the ionic signal before and after target recognition (ß). Electroneutral peptide nucleic acids and negatively charged DNA are selected as probes and targets, respectively. The experimental results showed that when adding the same number of targets, the ß value increased with the probe grafting density on the outer surface. A theoretical model with clearly defined physical properties of each probe and target has been established. Numerical simulations suggest that the decrease of the background current and the aggregation of targets at the mouth of nanochannels with increasing probe grafting density contribute to this enhancement. This work reveals the signal mechanism of probe-target recognition on the outer surface of nanochannels and suggests a general approach to the nanochannel/nanopore design leading to sensitivity improvement on the basis of relatively good selectivity.

Research on Optimization of Healthcare Waste Management System Based on Green Governance Principle in the COVID-19 Pandemic.

At present, strategies for controlling the COVID-19 pandemic have made significant and strategic strides; however, and the large quantities of healthcare treatment waste have become another important "battlefield". For example, in Wuhan, the production rate of healthcare waste in hospitals, communities, temporary storage, and other units was much faster than the disposal rate during the COVID-19 pandemic. Improving the efficiency of healthcare waste transfer and treatment has become an important task for government health and environmental protection departments at all levels. Based on the situation of healthcare waste disposal in Wuhan during the critical period of the pandemic, this paper analyzes and studies green governance principles and summarizes the problems that exist in the current healthcare waste management system. Through the establishment of temporary storage facilities along transit routes, digital simulation and bionic experiments were carried out in the Hongshan District of Wuhan to improve the efficiency of healthcare waste transfer. Furthermore, this study discusses the coordination and cooperation of government, hospitals, communities, and other departments in the healthcare waste disposal process and provides guiding suggestions for healthcare waste disposal nationwide in order to deal with potential risks and provide effective references in all regions.

Revealing the Critical Role of Probe Grafting Density in Nanometric Confinement in Ionic Signal via an Experimental and Theoretical Study.

The grafting density of probes at sensor interface plays a critical role in the performance of biochemical sensors. However, compared with macroscopic interface, the effects of probe grafting density at nanometric confinement are rarely studied due to the limitation of precise grafting density regulation and characterization at the nanoscale. Here, we investigate the effect from the grafting density of DNA probes on ionic signal for nucleic acid detection in a cylindrical nanochannel array (with diameter of 25 nm) by combing experiments and theories. We set up a theoretical model of charge distribution from close to inner wall of nanochannels at low probe grafting density to spreading in whole space at high probe grafting density. The theoretical results fit well with the experimental results. A reverse of ionic output from signal-off to signal-on occurs with increasing probe grafting density. Low probe grafting density offers a high current change ratio that is further enhanced using long-chain DNA probes or the electrolyte with a low salt concentration. This work develops an approach to enhance performance of nanochannel-based sensors and explore physicochemical properties in nanometric confines.

Estimating the Cultural Value of Wild Animals in the Qinling Mountains, China: A Choice Experiment.

In this study, we use the choice experiment method to evaluate the value of wild animals in the surrounding areas of the Changqing National Nature Reserve in China. For areas focused on biodiversity conservation, the results of wild animal value evaluation can provide a basis for the formulation of local ecological compensation standards. We identified wild animals, natural landscape features, infrastructure and facilities, and ticket price as major attributes determining the utility and value of the reserve area. The results of our field survey suggest that the cultural value of wild animals is significantly higher than the value of the infrastructure and other natural landscapes. Tourists indicated a willingness-to-pay of 31.4 Yuan to see wild animals in captivity, compared to 71.9 Yuan to see wild animals in the field. Moreover, tourists with different characteristics have different preferences for the cultural value of wildlife. Female tourists have a higher willingness-to-pay than male tourists. In addition, as age, education, and income level increase, tourists' willingness-to-pay also increases. These conclusions can provide a reference for local government to formulate wildlife protection compensation and ecotourism ticket pricing.