The economic system is a complex adaptive system (CAS), which is composed of many heterogeneous, dispersed and interconnected actors. Because of ignoring these features, traditional macroeconomic ...models have many defects. In view of the fact that economic security problems are characterized by multiple and miscellaneous source data, wide range of involvement and complex behavior, an economic system needs to be simulated. In this paper, based on big data technology, we conduct china's economic security simulation from three aspects: economic security simulation method, economic security simulation modeling and calibration technology, and economic security early warning simulation visualization technology. In the end, we apply the method of this paper to a case study of a rare earth new material company, and analyze the advantages and disadvantages of various safety investment schemes based on the simulation results. Case analysis proves that the method proposed in this paper can simulate economic dynamics to achieve dynamic assessment of economic development and economic security prediction.
To solve the problems of the decreased reliability and safety of battery pack due to the inconsistency between batteries after single batteries are grouped is of great significance to find an ...appropriate sorting method of single batteries. This study systematically reviews the available literature on battery sorting applications for battery researchers and users. These methods can be roughly divided into three types: direct measurement, sorting based on the model, and sorting based on the material chemistry of batteries. Among them, direct measurement is about the direct measurement of the state parameters of batteries using some professional instruments or testing tools to sort and group batteries with similar or close parameters. Sorting based on the model classifies batteries into groups by establishing a battery equivalent model and carrying out model identification and parameter estimation with machine learning or artificial intelligence algorithm. Sorting based on the material chemistry of batteries is to explore some characteristics related to the chemical mechanism inside the battery. On the basis of reading extensive literature, the methods for classification of battery are provided with an in-depth explanation, and each corresponding strengths and weaknesses of these methods are analyzed. Finally, the future developments of advanced sorting algorithms and batteries prospect.
A new Lewis acid promoted three-component reaction between the aziridine, arene and aldehyde has been developed. This reaction involves sequential ring opening of aziridine and Pictet–Spengler ...condensation and gives a broad range of cis-1,4-disubstituted tetrahydroisoquinolines in moderate yields with good diastereoselectivities under mild conditions. The methodology provides a rapid and convergent synthesis for the scaffold of tetrahydroisoquinoline and serves as a good tool for constructing the libraries of substituted tetrahydroisoquinolines.
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Purpose
This study aimed to elucidate the effects of long-term day and night shifts on liver function and lipid metabolism in a group of nurses.
Methods
This cross-sectional study in December 2019 ...was based on a group of nurses. A total of 1,253 physically healthy caregivers were included, including 1231 women and 22 men. A total of 886 nurses had long-term shift work (working in a rotating system for >1 year). The receiver operating characteristic (ROC) curve and logistic regression analyses were used to evaluate factors related to long-term shift work.
Results
We observed differences in liver and kidney indicators between the non-night and night shift groups. The ROC curve revealed that CHO (AUC: 62.4%), LDLC (AUC: 62%), and GLUO (AUC: 61.5%) were more related to the night shift. Logistic regression analysis showed that night shift work was associated significantly with CREA (log (OR) = −0.02, 95% CI: −0.04 to −0.01), CHO (log (OR) = −0.38, 95% CI: −0.67 to −0.09), and GLUO (log (OR) = −0.35, 95% CI: −0.56 to −0.17). This correlation was observed only for CHO and LDHC (CHO: log (OR) = −0.55, 95% CI: −0.98 to −0.12; LDLC: log (OR) = 0.83, 95% CI: 0.32, 1.4) after age standardization. After using propensity score matching, we did not find evidence to support that the indicators differed between night and non-night shift groups.
Conclusion
Our study observed an association of long-term night work with abnormal liver and kidney function and dyslipidemia, but the difference was not significant after strict age matching. Although these findings may support interventions for long-term night shift nurses, more detailed studies are needed to confirm.
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common enzymatic disorder of the erythrocytes that affects 400 million people worldwide. We developed a PCR-reverse dot blot (RDB) assay to ...screen twenty genotypes of seventeen Chinese G6PD mutations and investigate the spectrum of G6PD deficiency mutations in Dongguan District, Guangdong Province, in southern China.
The PCR-RDB assay consists of multiplex PCR amplification of seven fragments in the G6PD target sequence of wild-type and mutant genomic DNA samples followed by hybridization to a test strip containing allele-specific oligonucleotide probes. A total of 16,464 individuals were analyzed by a combination of phenotypic screening and genotypic detection using the PCR-RDB assay and DNA sequence analysis.
The PCR-RDB assay had a detection rate of 98.1%, which was validated by direct sequencing in a blind study with 100% concordance. The G6PD deficiency incidence rate in Dongguan District is 4.08%. Thirty-two genotypes from 469 individuals were found. The two most common variants were c.1376G>T and c.1388G>A, followed by c.95A>G, c.871G>A, c.392G>T, and c.1024 C>T. In addition, two rare mutations (c.703C>A and c.406C>T) were detected by DNA sequencing analysis. In our study, 65 cases harbored the C1311T/IVS polymorphism and 67 cases were homozygote.
The PCR-RDB assay we established is a reliable and effective method for screening G6PD mutations in the Chinese population. Data on the spectrum of mutations in the Dongguan District is beneficial to the clinical diagnosis and prevention of G6PD deficiency.
A new silver(I) triflate‐promoted tandem reaction comprising the ring opening of aziridines and a Michael reaction has been developed. Using secondary amines or primary amines as nucleophiles, this ...methodology allows for the synthesis of cis‐1‐alkyl‐4‐aminotetrahydroisoquinolines or cis‐1,3‐disubstituted isoindolines in good yields with excellent diastereoselectivities, respectively. Besides, easy operation and mild reaction conditions are also notable features of this tandem reaction.
The pathogenicity and virulence of the Omicron strain have weakened significantly pathogenesis of Omicron variants. Accumulating data indicated accessory proteins play crucial roles in host immune ...evasion and virus pathogenesis of SARS-CoV-2. Therefore, the impact of simultaneous deletion of accessory protein ORF7a, ORF7b and ORF8 on the clinical characteristics and specific immunity in Omicron breakthrough infected patients (BIPs) need to be verified.
Herein, plasma cytokines were identified using a commercial Multi-cytokine detection kit. Enzyme-linked immunosorbent assay and pseudovirus neutralization assays were utilized to determine the titers of SARS-CoV-2 specific binding antibodies and neutralizing antibodies, respectively. In addition, an enzyme-linked immunospot assay was used to quantify SARS-CoV-2 specific T cells and memory B cells.
A local COVID-19 outbreak was caused by the Omicron BA.2 variant, which featured a deletion of 871 base pairs (∆871 BA.2), resulting in the removal of ORF7a, ORF7b, and ORF8. We found that hospitalized patients with ∆871 BA.2 had significantly shorter hospital stays than those with wild-type (WT) BA.2. Plasma cytokine levels in both ∆871 BA.2 and WT BA.2 patients were within the normal range of reference, and there was no notable difference in the titers of SARS-CoV-2 ancestor or Omicron-specific binding IgG antibodies, neutralizing antibody titers, effector T cells, and memory B cells frequencies between ∆871 BA.2 and WT BA.2 infected adult patients. However, antibody titers in ∆871 BA.2 infected adolescents were higher than in adults.
The simultaneous deletion of ORF7a, ORF7b, and ORF8 facilitates the rapid clearance of the BA.2 variant, without impacting cytokine levels or affecting SARS-CoV-2 specific humoral and cellular immunity in Omicron-infected individuals.
Interplanetary coronal mass ejections (ICMEs) and the driven geomagnetic storms have a profound influence on the ionosphere, potentially leading to a degradation in positioning performance. In this ...study, we made a comprehensive analysis of the entire process of the impact of a typical ICME and its driven geomagnetic storm on the low-latitude ionosphere during March 13–14, 2022 (π-day storm) and the positioning performance of Global Navigation Satellite System (GNSS). During the passage of the ICME event, significant ionospheric scintillation, and TEC (total electron content) disturbances were observed in the low-latitude Hong Kong region. The ICME sheath region intensively compressed the magnetosphere via solar wind dynamic pressure enhancement and subsequently drove the storm main phase. It is found that both the magnetospheric compression that formed the storm initial phase and the storm main phase caused ionospheric scintillation. In comparison, the intensity of the ionospheric scintillation caused by the intense magnetospheric compression just before the storm main phase is even more pronounced. We also analyzed the impact of storms on standard point positioning (SPP), precise point positioning (PPP) and real-time kinematic (RTK) techniques. The positioning accuracies of single-frequency SPP and PPP experienced the most severe decline, and there was a noticeable increase in the initialization time for dual-frequency static PPP and RTK during the event. RTK demonstrated a shorter convergence time and higher accuracy during this event, but it was limited to short-baseline RTK (<30 km).
Objectives
Ensuring the accuracy of transclavicular‐transcoracoid drilling in the anatomical reconstruction of the coracoclavicular ligament complex with minimally invasive incisions remains a major ...problem for inexperienced surgeons. The purpose of this study was to design an assembly guide device for transclavicular‐transcoracoid drilling with minimally invasive incisions, to manufacture the finished product, and to compare its feasibility and accuracy with the existing C‐shape guide devices and free‐hand techniques.
Methods
An assembly‐type guide device was designed and produced using computer‐aided design and three‐dimensional printing. The specimen data of 54 human shoulders from 27 gross specimen (14 males and 13 females) treated by free‐hand drilling, C‐shape device drilling, and assembly‐type guide device drilling from October 2018 to January 2021 were analyzed in a controlled laboratory study. Fifty‐four human shoulder specimens were randomly assigned into free‐hand (n = 18), C‐shape (n = 18), and assembly (n = 18) groups by drawing lots for transclavicular‐transcoracoid drilling by three inexperienced surgeons. After the drilling procedure was completed and the devices were removed, the operation outcomes were assessed and evaluated. Distances from the tunnel edge to the coracoid's medial (dm) and lateral (dl) edges, operation time, and tunnel location zones on the coracoid's inferior surface of all specimens in the three groups were measured to evaluate the surgical accuracy and efficiency.
Results
All specimens in the three groups completed the drilling operation successfully and were correctly measured. The distance differences (dd) between dm and dl in the free‐hand, C‐shape, and assembly groups were 3.2 ± 1.8 mm, 1.8 ± 1.0 mm, 1.0 ± 0.8 mm, respectively. The dd of the free‐hand group was higher than that of the other two groups (p < 0.001). The tunnel exit points on the inferior coracoid surface located in undesired zones were six (33%), one (6%), and zero in the free‐hand group, C‐shape group, and assembly‐type group, respectively (p = 0.012). The operation time in the free‐hand, C‐shape, and assembly groups were 198 ± 36 s, 256 ± 64 s, and 353 ± 88 s, respectively. The operation time of each group significantly differed from that of the others (p < 0.001).
Conclusion
The assembly‐type devices may be the first choice for inexperienced surgeons while both the C shape devices and assembly‐type guide devices achieved higher accuracy than free‐hand techniques.
The assembly guide device designed in our study could accurately locate the tunnel path. The concentric circle sliding arc was designed to make the guiding angle adjustable and matching the various drilling angles. The center of the concentric arc coincides with the midpoint of the hook, which could ensure the preset tunnel path pass through the midpoint of the inferior coracoid base, no matter what position the guiding part was on the arc.
Traditional theoretical models used to predict shale permeability generally ignore the influence of the effective stress and gas sorption-induced strain on the gas transport process. Consequently, ...the predicted permeability may deviate from the experimental results, wherein the coupling effect of the fluid and solid is involved. To improve the accuracy of the permeability model for shale stones, a hydraulic diameter-based generic permeability model was proposed that couples the effective stress, gas sorption, and flow-regime effects. Three special degenerate case models, based on the generic model, were validated using three corresponding experimental conditions. Sensitivity studies have demonstrated that the flow-regime effect is sensitive to the size of the equivalent hydraulic diameter, whereas the poroelastic effect is sensitive to the initial porosity and compressibility factor of the shale bulk. The two effects cannot be decoupled from shale permeability during the experimental process. The contribution of the adsorption effects to permeability, as reflected by the Langmuir pressure constant of the matrix, is greater in the high-pressure region, where pore elasticity dominates. The contribution of the adsorption effects to permeability, as reflected by the Knudsen number, is weaker in the low-pressure region, where the flow regime dominates. In addition, the contribution of the adsorption effect varies much more in the poroelasticity deformation than in the fluid dynamics.
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