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Background:. Since the outbreak of coronavirus disease 2019 (COVID-19), human mobility restriction measures have raised controversies, partly because of the inconsistent findings. An empirical study is promptly needed to reliably assess the causal effects of the mobility restriction. The purpose of this study was to quantify the causal effects of human mobility restriction on the spread of COVID-19. Methods:. Our study applied the difference-in-difference (DID) model to assess the declines of population mobility at the city level, and used the log–log regression model to examine the effects of population mobility declines on the disease spread measured by cumulative or new cases of COVID-19 over time after adjusting for confounders. Results:. The DID model showed that a continual expansion of the relative declines over time in 2020. After 4 weeks, population mobility declined by −54.81% (interquartile range, −65.50% to −43.56%). The accrued population mobility declines were associated with the significant reduction of cumulative COVID-19 cases throughout 6 weeks (ie, 1% decline of population mobility was associated with 0.72% [95% CI: 0.50%–0.93%] reduction of cumulative cases for 1 week, 1.42% 2 weeks, 1.69% 3 weeks, 1.72% 4 weeks, 1.64% 5 weeks, and 1.52% 6 weeks). The impact on the weekly new cases seemed greater in the first 4 weeks but faded thereafter. The effects on cumulative cases differed by cities of different population sizes, with greater effects seen in larger cities. Conclusions:. Persistent population mobility restrictions are well deserved. Implementation of mobility restrictions in major cities with large population sizes may be even more important.

Since the 18th National Congress of the Communist Party of China(CPC), the CPC and the government have highligh-ted the development of traditional Chinese Medicine(TCM) and issued a series of policies, such as the Plan for Protection and Deve-lopment of Chinese Medicinal Materials(2015-2020) forwarded by the General Office of the State Council in 2015, the Plan for Healthy Development of Traditional Chinese Medicine(2015-2020) released by the General Office of the State Council in the same year, the Healthy China 2030 Plan published by the CPC Central Committee and the State Council in 2016, the Law of the People's Republic of China on Traditional Chinese Medicine which took effect on July 2017, On the Preservation and Innovative Development of Traditional Chinese Medicine promulgated by CPC Central Committee and the State Council in 2019, and Plan for the Development of Traditional Chinese Medicine during the 14th Five-Year Plan Period of China released by the General Office of the State Council in March 2022, to promote the development of the TCM industry, which have brought historical opportunities to the TCM industry. However, TCM industry faces various challenges in the development. In terms of drug development in TCM, the current studies mainly focused on the chemical research and technical requests, which neglected TCM characteristics and cased in conformity between new drug transformation of TCM and clinical practice. Therefore, a more considerable and profound authoritative guideline is needed, and innovative thought and research are necessary for academics and the industry. Through the investigation of the development TCM industry in recent years, this study summarized the policies on and trends of Chinese medicinal materials, new drug development in TCM, catalogue of national basic drugs, and national basic health insurance, and proposed suggestions for further development of TCM industry.

Since the implementation of drug registration in China, the classification of Chinese medicine has greatly met the needs of public health and effectively guided the transformation, inheritance, and innovation of research achievements on traditional Chinese medicine(TCM). In the past 30 years, the development of new Chinese medicine has followed the registration transformation model ofquot; one prescription for single drugquot;. This model refers to the Ramp;D and registration system of modern drugs, and approximates to thequot; law-abidingquot; medication method in TCM clinic, while it rarely reflects the sequential therapy of syndrome differentiation and comprehensive treatment with multiple measures. In 2017, Opinions on Deepening the Reform of Review and Approval System and Encouraging the Innovation of Drugs and Medical Devices released by the General Office of the CPC Central Committee and the General Office of the State Council pointed out that it is necessary toquot; establish and improve the registration and technical evaluation system in line with the characteristics of Chinese medicine, and handle the relationship between the traditional advantages of Chinese medicine and the requirements of modern drug researchquot;. Therefore, based on the development law and characteristics of TCM, clinical thinking should be highlighted in the current technical requirements and registration system of research and development of Chinese medicine. Based on the current situation of registration supervision of Chinese medicine and the modern drug research in China, the present study analyzed limitations and deficiency ofquot; one prescription for single drugquot; in the research and development of Chinese medicine. Additionally, a new type ofquot; series prescriptionsquot; was proposed, which was consistent with clinical thinking and clinical reality. This study is expected to contribute to the independent innovation and high-quality development of the TCM industry.

Just-in-time production in large enterprises along with the factory’s limited space highlights the need for scheduling tools that consider blocking conditions. This study contributes to the scheduling literature by developing an effective metaheuristic to address the Blocking Flowshop Scheduling Problems with Sequence-Dependent Setup-Times (BFSP with SDSTs). Including a new constructive heuristic and a local search mechanism customized for the blocking and setup time features, the Extended Iterated Greedy (EIG) algorithm effectively solves this highly intractable scheduling extension. The performance of the EIG algorithm is compared with that of the best-performing algorithms in the literature developed to solve the BFSP with SDSTs. Extensive numerical tests and statistical analyses verify EIG’s superiority over the benchmark algorithms and show that EIG performs steadily over various operational situations. Applications of the improved algorithm in this study are worthwhile topics to solve other complex scheduling problems.

A set of hot deformation experiments 6082 aluminum alloy were carried out on the Gleeble-3500 thermal simulation machine. The true stress-strain curves were obtained in the condition of temperatures 425 ̊C,450 ̊C,475 ̊C and 500 ̊C, strain rate 0.01s-1, 0.1s-1, 1s-1 and 10s-1. At the low strain rate (0.01s-1, 0.1s-1), true stress-strain curves exhibited typical work hardening and flow softening features, but at the high strain rate (1s-1, 10s-1), true stress-strain curves just exhibited typical work hardening. The peak stress of current alloy decreased with temperature and increased with strain rate, which can be represented by a hyperbolic sine equation using the Zener-Hollomon parameter (Z). The processing map was calculated and analyzed according to dynamic materials mode (DMM). The processing map showed the reasonable hot working region of 6082 aluminum ally.

Objective: To analyze the relationship between KRAS/PIK3CA gene mutation and clinicopathologic characteristics such as gender, age, tumor location, pathological pattern, histological grade, TNM stage and lymph node metastasis, especially the relationship with distant metastasis of colorectal cancer. Methods: A total of 94 cases of colorectal cancer samples surgically resected in Gastrointestinal Surgery Department of our hospital from January 2012 to August 2015 were collected, DNA was extracted and then KRAS and PIK3CA gene sequencing was carried out; their clinicopathologic characteristics (gender, age, tumor location, pathological pattern, histological grade, TNM stage, lymph node metastasis and distant metastasis) were analyzed, the relationship between KRAS/PIK3CA gene mutation and above factors, especially distant metastasis was analyzed, and statistical analysis processing was conducted; patients received 3-year follow-up, distant metastasis and recurrence were observed, and the number of their cases was counted, statistically analyzed and processed. Results: KRAS gene mutation was not associated with gender, age, tumor location, pathological pattern and histological grade, and significantly associated with distant metastasis, lymph node metastasis and TNM stage; PIK3CA was not associated with gender, age, tumor location, pathological pattern and histological grade, and associated with TNM stage, lymph node metastasis and distant metastasis; 7 cases (7.4%) were with mutation of both KRAS and PIK3CA (double positive), and 55 cases (57.4%) were with no mutation at all (double negative); in double positive cases, 5 cases were with distant metastasis, metastasis rate was 71.4% and higher than that of double negative (16/55, 29.1%), and there were statistical differences; it was found in follow-up that metastasis rate of KRAS mutant type was higher than that of wild type, and differences were statistically significant; recurrence rates of KRAS and PIK3CA mutant type were higher than those of wild type, and differences were statistically significant. Conclusion: KRAS and PIK3CA gene mutation rates in colorectal cancer tissue are associated with TNM stage, lymph node metastasis and distant metastasis, and mutant type is more susceptible to distant metastasis and recurrence than wild type; KRAS and PIK3CA gene mutation may have certain predictive value for distant metastasis and recurrence of colorectal cancer, and have certain guiding significance for judgment of patients’ prognosis.

Objective: To study the detection of serum OPN, sLAG-3 and DKK-1 contents in patients with gastric cancer and their relationship with tumor pathological stage and apoptosis gene expression. Methods: A total of 105 cases of patients with gastric cancer and 105 cases of healthy subjects were selected and enrolled in gastric cancer group and control group, and serum OPN, sLAG-3 and DKK-1 contents as well as expression levels of Survivin, FLIP and Bcl-2 in gastric cancer tissue were detected. Results: Serum OPN and DKK-1 contents of gastric cancer group were significantly higher than those of control group, and sLAG-3 content was significantly lower than that of control group; serum OPN and DKK-1 contents of gastric cancer patients with TNM I-II stage as well as high and middle differentiation were lower than those of patients with TNM III-IV stage, low differentiation and un-differentiation, and sLAG-3 contents were higher than those of patients with TNM III-IV stage, low differentiation and un-differentiation; mRNA contents of Survivin, FLIP and Bcl-2 in gastric cancer tissue with TNM I-II stage as well as high and middle differentiation were significantly lower than those in gastric cancer tissue with TNM III-IV stage, low differentiation and non-differentiation, and they were positively correlated with serum OPN and DKK-1 contents and negatively correlated with serum sLAG-3 content. Conclusion: Serum OPN and DKK-1 contents abnormally increase and sLAG-3 content abnormally decreases in patients with gastric cancer, and OPN, sLAG-3 and DKK-1 contents have correlation with tumor stage, differentiation and apoptosis gene expression.

Uniaxial tensile and compressive tests were performed at room temperature on extruded AZ31 Mg alloy specimens and distinct tensile-compressive anisotropy was detected. Deformed specimens were examined and the results indicate that the generation of {10\(\bar 1\)2}〈10\(\bar 1\)1〉 twin is responsible for the mechanical anisotropy. A rate independent crystal plasticity model, which accounts for both slip and twinning, was developed for polycrystalline hexagonal close packed (HCP) materials. Model predictions for the stress-strain curves and texture evolution were in reasonable agreement with the experimental results. Specifically, the model captured the three stages of strain hardening for uniaxial-compression. By comparing stress-strain curves and texture evolution between model predictions and experimental measures, information about the dominant slip and twinning systems active at room temperature was deduced.

Two alternative formulations of single crystal plasticity model were introduced respectively and two schemes were implemented in the explicit FE code with software ABAQUS/Explicit by writing the user subroutine VUMAT. Meshes containing material data were created with solid elements. Each element represented an individual grain, and the grain orientations were explicitly stored and updated at each increment. Tangential modulus method was employed to calculate the plastic shear strain increment of deformation systems in combination with a hardening law to describe the hardening responses. Both two developed subroutines were applied to simulate the texture evolution during the uniaxial tension of copper (FCC), cold rolling of IF steel (BCC) and uniaxial compression of AZ31 magnesium alloy (HCP). The predicted texture distributions are in qualitative agreement with the experimental results.

Grain size and texture distributions have great influences on the mechanical properties of extruded rods. In order to study grain size and texture evolution during the hot extrusion process, direct extrusion tests were carried out with a variety of extrusion parameters (extrusion ratio, temperature and velocity) for commercial as-cast AZ31 magnesium alloys. Extruded specimens were investigated by optical microscopy (OM) and electron backscattered diffraction (EBSD). Experimental results show that extrusion ratio is the most important parameter for grain size refinement. Basal fiber textures with various (0 0 0 2) pole intensities are observed in extruded rods. Maximum intensities increase with the decreasing extrusion ratio and the increasing velocity, while the influence of temperature depends on the value of extrusion ratio and velocity.

To gain a better understanding about the influence of initial texture on deformation behaviour of sheet metals, an incremental-update formulation is adopted for implementing rate-dependent crystal plasticity model into the explicit finite element package, ABAQUS/Explicit. In this formulation, the configuration in the last increment serves as a reference frame, and the stress, grain orientation and hardening behaviour of crystal are updated at the end of each increment. Two user subroutines VUMAT are developed, respectively, for face-centred cubic and hexagonal close packed alloys due to different deformation mechanisms. Earing behaviours of aluminium sheet and AZ31 alloy sheet are simulated for model validation.

To gain a better understanding about texture evolution during rolling process of AZ31 alloy, polycrystalline plasticity model was implemented into the explicit FE package, ABAQUS/Explicit by writing a user subroutine VUMAT. For each individual grain in the polycrystalline aggregate, the rate dependent model was adopted to calculate the plastic shear strain increment in combination with the Voce hardening law to describe the hardening response, the lattice reorientation caused by slip and twinning were calculated separately due to their different mechanisms. The elasto-plastic self consistent (EPSC) model was employed to relate the response of individual grain to the response of the polycrystalline aggregate. Rolling processes of AZ31 sheet and as-cast AZ31 alloy were simulated respectively. The predicted texture distributions are in qualitative agreement with experimental results.