The hotel uses modern information technology to establish a customer data group, which contains information about the customer's information on space configuration, color design, etc., and uses ...scientific operation methods to accelerate the rapid, transformation and upgrading of the hotel. The rapid development of information technology represented by the big intelligent mobile cloud has a lot of functions, can meet the needs of different customers and diversified characteristics at the same time, and provides a complete, stable and accurate information integration platform for hotel system management. The main research directions of DASH include client adaptive algorithm design, multi-client fairness and resource utilization issues, client improvement under multiple servers, and server load balancing. The development and application of scientific and technological information has broken through the development path of the hotel management system, providing new development space and opportunities for the improvement of the hotel management system, but at the same time it will also face more new challenges. Therefore, this article focuses on the characteristics of the tourism accommodation management system under the big data environment, and analyzes the development of the hotel management system under the network environment. The purpose is to provide some reference and reference significance.
In recent years, China has experienced severe and persistent air pollution associated with rapid urbanization and climate change. Three years' time series (January 2014 to December 2016) ...concentrations data of air pollutants including particulate matter (PM2.5 and PM10) and gaseous pollutants (SO2, NO2, CO, and O3) from over 1300 national air quality monitoring sites were studied to understand the severity of China's air pollution. In 2014 (2015, 2016), annual population-weighted-average (PWA) values in China were 65.8 (55.0, 50.7) μg m−3 for PM2.5, 107.8 (91.1, 85.7) μg m−3 for PM10, 54.8 (56.2, 57.2) μg m−3 for O3_8 h, 39.6 (33.3, 33.4) μg m−3 for NO2, 34.1 (26, 21.9) μg m−3 for SO2, 1.2 (1.1, 1.1) mg m−3 for CO, and 0.60 (0.59, 0.58) for PM2.5/PM10, respectively. In 2014 (2015, 2016), 7% (14%, 19%), 17% (27%, 34%), 51% (67%, 70%) and 88% (97%, 98%) of the population in China lived in areas that meet the level of annual PM2.5, PM10, NO2, and SO2 standard metrics from Chinese Ambient Air Quality Standards-Grade II. The annual PWA concentrations of PM2.5, PM10, O3_8 h, NO2, SO2, CO in the Northern China are about 40.4%, 58.9%, 5.9%, 24.6%, 96.7%, and 38.1% higher than those in Southern China, respectively. Though the air quality has been improving recent years, PM2.5 pollution in wintertime is worsening, especially in the Northern China. The complex air pollution caused by PM and O3 (the third frequent major pollutant) is an emerging problem that threatens the public health, especially in Chinese mega-city clusters. NOx controls were more beneficial than SO2 controls for improvement of annual PM air quality in the northern China, central, and southwest regions. Future epidemiologic studies are urgently required to estimate the health impacts associated with multi-pollutants exposure, and revise more scientific air quality index standards.
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•Air pollution in China were characterized with three-year observed data.•Population-weighted-average concentrations in provinces, mega-city clusters and regions were calculated.•The complex air pollution caused by PM and O3 is an emerging problem in Chinese mega-city clusters.•Spatial distributions of annual average air pollutants in China were conducted.
The advent of intense ultrashort optical pulses spanning a frequency range from terahertz to the visible has opened a new era in the experimental investigation and manipulation of quantum materials. ...The generation of strong optical field in an ultrashort time scale enables the steering of quantum materials nonadiabatically, inducing novel phenomenon or creating new phases which may not have an equilibrium counterpart. Ultrafast time‐resolved optical techniques have provided rich information and played an important role in characterization of the nonequilibrium and nonlinear properties of solid systems. Here, some of the recent progress of ultrafast optical techniques and their applications to the detection and manipulation of physical properties in selected quantum materials are reviewed. Specifically, the new development in the detection of the Higgs mode and photoinduced nonequilibrium response in the study of superconductors by time‐resolved terahertz spectroscopy are discussed.
The advent of ultrashort optical pulses has provided unprecedented opportunities to probe and manipulate physical properties of quantum materials. There have been rapid growing discoveries of photoinduced new phenomena and nonlinear properties. A review on recent progress of ultrafast optical characterization and manipulation of quantum states, specifically in systems with broken‐symmetry states or phase transitions, and prospects are provided.
1-Ethyl-3-methylimidazolium ethyl sulfate (EMIES) is a novel ionic liquid with potential industrial applications. Attenuated total reflectance infrared spectroscopy, (1)H NMR spectroscopy, and ...quantum chemical calculations were employed to investigate the molecular interactions between water and EMIES. The infrared spectra were analyzed by two methods: excess spectroscopy and two-dimensional correlation spectroscopy. This showed that the hydrogen bond involving the -SO(3) group in the ethyl sulfate anion (ES) was enhanced, while those involving the aromatic C-H groups of 1-ethyl-3-methylimidazolium cation (EMI) were weakened in the presence of water. During the process of increasing water concentration, the hydrogen bonding interaction between H(2)O and SO is prior to that between H(2)O and the C-H group on the imidazolium ring. At low concentrations, water interacts selectively with -SO(3) in the ethyl sulfate anion, while, at high concentrations (mole fraction of water equal or greater than 0.6), it can also form hydrogen bonds directly with the imidazolium ring. The following sequential order of interaction strength is established: EMI-water-ES > EMI-ES > ES-water > EMI-water.
Abstract
Background
Coronavirus disease 2019 (COVID-19) has become a public health emergency. The widely used reverse transcription–polymerase chain reaction (RT-PCR) method has limitations for ...clinical diagnosis and treatment.
Methods
A total of 323 samples from 76 COVID-19–confirmed patients were analyzed by droplet digital PCR (ddPCR) and RT-PCR based 2 target genes (ORF1ab and N). Nasal swabs, throat swabs, sputum, blood, and urine were collected. Clinical and imaging data were obtained for clinical staging.
Results
In 95 samples that tested positive by both methods, the cycle threshold (Ct) of RT-PCR was highly correlated with the copy number of ddPCR (ORF1ab gene, R2 = 0.83; N gene, R2 = 0.87). Four (4/161) negative and 41 (41/67) single-gene positive samples tested by RT-PCR were positive according to ddPCR with viral loads ranging from 11.1 to 123.2 copies/test. The viral load of respiratory samples was then compared and the average viral load in sputum (17 429 ± 6920 copies/test) was found to be significantly higher than in throat swabs (2552 ± 1965 copies/test, P < .001) and nasal swabs (651 ± 501 copies/test, P < .001). Furthermore, the viral loads in the early and progressive stages were significantly higher than that in the recovery stage (46 800 ± 17 272 vs 1252 ± 1027, P < .001) analyzed by sputum samples.
Conclusions
Quantitative monitoring of viral load in lower respiratory tract samples helps to evaluate disease progression, especially in cases of low viral load.
As a public health emergency, quantitative monitoring of coronavirus disease 2019 (COVID-19) in lower respiratory tract samples in infected patients helps to evaluate disease progression, especially in cases of low viral load.
Microplastic contamination has been considered as a global environmental problem in marine ecosystem. Due to small size (< 5 mm) in overlapping with that of microalgae, microplastics can easily be ...ingested by a wide range of marine copepods both in the laboratory and in situ. Although many studies have reported adverse effects of microplastics on marine copepods, it still lacks a systematic overview about the bioavailability of microplastics and their potential ecological consequences. As copepods dominate zooplankton biomass and provide an essential trophic link in marine ecosystem, this review indicates the bioavailability and toxicity of microplastics in such taxon depend on the shape, size, abundance, and properties of plastics. Also, ours is purposed to tease out the possible molecular mechanisms behind. Microplastic ingestion is prevalent; they impede food intake, block the digestive tract, and cause physiological stress in copepods (e.g., immune responses, metabolism disorders, energy depletion, behavioral alterations, growth retardation, and reproduction disturbance). Notably, in response to microplastic exposure, the copepods show both species- and stage-specificity. Furthermore, microplastics can serve as vectors of organic contaminants (e.g., triclosan, chlorpyrifos, and dibutyl phthalate) and thus increase their toxicity in marine copepods, consequently aggravating the adverse impacts of microplastics in marine ecosystem. Given that most previous studies have partially used pristine microplastics and their short-term exposure might have undervalued their negative effects, more multigenerational mechanistic researches (for example, via an integration of omics-based technology and phenotypic trait analysis) are urgently required for numerous marine copepods exposed to environmental-characteristics plastics as demonstrated by aged microplastics at environmentally realistic concentrations and added with other environmental pollutants; thus it will not only provide mechanistic insights into the biological impacts of microplastics, but also help make the seawater-benchmark setting and ecological assessment for microplastic pollution in marine environment.
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•Microplastics have been regarded as a global threat to marine ecosystem.•Several factors affect microplastic bioavailability to marine copepods.•Copepods show species- and stage-specific responses against microplastics.•Microplastics are potential vectors of organic contaminants to copepods.•Perspectives have been suggested for marine microplastic stress study.
SUMMARY
Acer truncatum (purpleblow maple) is a woody tree species that produces seeds with high levels of valuable fatty acids (especially nervonic acid). However, the lack of a complete genome ...sequence has limited both basic and applied research on A. truncatum. We describe a high‐quality draft genome assembly comprising 633.28 Mb (contig N50 = 773.17 kb; scaffold N50 = 46.36 Mb) with at least 28 438 predicted genes. The genome underwent an ancient triplication, similar to the core eudicots, but there have been no recent whole‐genome duplication events. Acer yangbiense and A. truncatum are estimated to have diverged about 9.4 million years ago. A combined genomic, transcriptomic, metabonomic, and cell ultrastructural analysis provided new insights into the biosynthesis of very long‐chain monounsaturated fatty acids. In addition, three KCS genes were found that may contribute to regulating nervonic acid biosynthesis. The KCS paralogous gene family expanded to 28 members, with 10 genes clustered together and distributed in the 0.27‐Mb region of pseudochromosome 4. Our chromosome‐scale genomic characterization may facilitate the discovery of agronomically important genes and stimulate functional genetic research on A. truncatum. Furthermore, the data presented also offer important foundations from which to study the molecular mechanisms influencing the production of nervonic acids.
Significance Statement
Here, we provide the first report on the Acer truncatum genome. Our work provides extensive genetic resources necessary for very long‐chain monounsaturated fatty acid biosynthesis.
A new class of highly efficient and stable, blue‐phosphorescent PtII complexes based on a tetradentate chelating framework has been found to exhibit highly sensitive and reversible responses to ...multiple external stimuli including temperature, pressure, and UV irradiation with distinct phosphorescent color switching—from blue to red or white. Intermolecular excimer formation is the main origin of this intriguing multi‐response phenomenon. Highly efficient singlet‐oxygen sensitization by the PtII compounds yields UV‐light‐induced phosphorescence enhancement and color switching.
Platinum gets the blues: Structural rigidification of PtII complexes has been found to be highly effective in achieving highly efficient and stable, dual emissive phosphorescent species that switch color and intensity in response to temperature, pressure, and UV light/oxygen.
Flexible smart surfaces with tunable wettability are promising for emerging wearable uses. However, currently, wearable superhydrophobic surfaces with dynamic wetting behaviors are rarely reported. ...Here, a skin‐like superhydrophobic elastomer surface with switchable lotus leaf and rose petal states is reported. Direct laser writing technique is employed for one‐step, programmable, large‐scale fabrication of monolithic and hierarchical micro‐nanostructures on elastomer, leading to strong water repellence. The surface topography can be finely regulated in a rapid and reversible manner by simple stretching, providing the feasibility of controlling the surface wettability by simple body motions. The ability to switch wetting states enables the surface to capture and release multiple droplets in parallel. Furthermore, the active surface can be applied to the joints of fingers and operate as a droplet manipulator under finger motions without requiring energy supply or external appliance. In this work, dynamic tuning of wetting properties is integrated into the design of skin‐like wearable surfaces, revealing great potential in versatile applications such as wearable droplet manipulator, portable actuator, adaptive adhesion control, liquid repellent skin, and smart clothing.
A skin‐like wearable superhydrophobic surface with switchable lotus leaf and rose petal states is reported. One‐step laser processing on a deformable elastomer enables rapid and reversible tailoring of hierarchical structures and wetting properties. The wearable surface can be compliant to finger joints and operates as droplet tweezers under finger motions without energy supply or external appliance.
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