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In order to introduce self-piercing rivet (SPR) technique to component connections of thin-walled steel structures, 78 SPR joints were tested to evaluate their quality and the shear strength. Parameters included in this test program were the sheet thickness, and the rivet. Based on test results, the research developed an empirical formula between the combination thicknesses of sheet and rivet length, and proposed quality evaluation standard of SPR connections and a new design method of shear strength. The test results showed that sheet thickness and sheet thickness ratio had a great effect on failure mode, and rivet length was a key factor on shear properties of SPR connections. The proposed quality evolution standard and design calculation method of shear strength in this paper had certain reasonability and reliability.

With the purpose of introducing a new connection to cold-formed steel structure, this paper presents an experimental investigation of cold-formed steel (CFS) shear walls with self-piercing riveted (SPR) connections under monotonic and reversed cyclic loading. The effects of loading type (Monotonic and Cyclic), rivet spacing at the steel sheet edges, rivet number at CFS framing joints, axial compression ratio, and the steel sheathing types (steel sheet sheathing and corrugated steel sheathing) on mechanical behavior and failure modes of CFS shear walls were investigated. The shear strength, initial stiffness, and ductility of CFS shear walls with SPR connections were evaluated by comparing to the results of CFS shear walls with self-drilling screw connections under the same condition. Lateral loading, safety factor, and resistance factor under the wind and seismic loads were determined in accordance with test results of CFS shear wall with SPR connections. The research indicated that the rivet spacing at the sheet edges was a key factor affecting failure modes and mechanical properties of CFS shear walls. The relationship of shear strength and ultimate deformation decreased linearly with the increase of the rivet spacing. Compared to CFS shear walls with self-drilling screw, CFS shear walls with SPR have significantly improved shear strength and stiffness. Safety factor and resistance factor recommended by AISI Seismic Design Standard are conservative for the wind and seismic design of CFS shear wall using SPR connections.

Linlin Song,1 Jianyong Lei,1 Ke Jiang,1 Yali Lei,2 Yuting Tang,2 Jingqiang Zhu,1 Zhihui Li,1 Huairong Tang2 1Thyroid and Parathyroid Surgery Center, West China Hospital of Sichuan University, Chengdu 610041, People’s Republic of China; 2Health and Management Center, West China Hospital of Sichuan University, Chengdu 610041, People’s Republic of ChinaCorrespondence: Huairong TangHealth and Management Center, West China Hospital of Sichuan University, Chengdu 610041, People’s Republic of ChinaTel/Fax +86-28-85422933Email thrhuaxi11@163.comBackground and Aim: The relationship between subclinical hypothyroidism (SHYPO) and sleep quality is still unclear. Our objective was to compare the sleep quality between SHYPO patients and a control group with normal thyroid function.Methods: A total of 2224 patients with SHYPO and 12,622 euthyroid (EUTH) control group patients were included in the present study. The Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality. The sleep outcomes were compared to explore the association between SHYPO and sleep quality. Furthermore, we tried to identify the risk factors of poor sleep in SHYPO patients.Results: Compared to the EUTH control patients, SHYPO patients had a higher PSQI score (6.83 ± 2.67 vs 6.64 ± 2.63, p =0.004) and a higher proportion of poor sleepers (67.09% vs 64.75%, p =0.033). Moreover, subjects with SHYPO were associated with poorer sleep (Odd Ratio (OR) 1.120, 95% Confidence Intervals (CI) 1.016 to 1.235, p =0.023), longer sleep latency (OR 1.162, 95% CI 1.053 to 1.282, p =0.003), and shorter sleep duration (OR 1.148, 95% CI 1.019 to 1.293, p =0.023) after adjusting for potential confounders. Furthermore, we found that lower age, lower body mass index, and women were risk factors for poor sleep quality in SHYPO patients.Conclusion: Our findings suggest a relationship between SHYPO and poor sleep quality in a large Chinese population.Keywords: subclinical hypothyroidism, sleep quality, PSQI

The paper presents an experimental investigation on the shear strength of self-piercing rivet connections used in thin-walled steel structures. The test program included specimen variations in the number of rivets in each connection, rivet spacing, end distance, and steel sheet thickness. According to the experimental results, the curve of load-slip, peak load, and failure mechanism for all specimens were analyzed. Parameters of riveting in terms of end distance, spacing, arrangement, length, and thickness difference between connection components were studied on their effects for shearing performances of self-piercing rivet connections. A design method based on the model of transmission dynamics of infectious diseases was proposed for calculating the shear strength of the rivet connections. The strength reduction due to the effect of group rivets was considered in the new method.

Linlin Song,1,2 Jingqiang Zhu,1 Zhihui Li,1,3 Tao Wei,1,3 Rixiang Gong,1,3 Jianyong Lei1 1Thyroid and Parathyroid Surgery Center, West China Hospital of Sichuan University, Chengdu 610041, People’s Republic of China; 2West China School of Medicine, Sichuan University, Chengdu 610065, People’s Republic of China; 3Thyroid and Breast Surgery Center, Chengdu Shang Jin Nan Fu Hospital, Chengdu 611700, People’s Republic of ChinaCorrespondence: Jianyong LeiThyroid and Parathyroid Surgery Center, West China Hospital of Sichuan University, Chengdu 610041, People’s Republic of ChinaTel +86 288 542 3822Fax +86 288 542 3822Email leijianyong11@163.comBackground and Aims: The prognosis of papillary thyroid carcinoma (PTC) is highly variable, even for high-risk cases. The predictive and prognostic role of the lymphocyte-to-monocyte ratio (LMR) has been reported in other cancers. The aim of our present study was to explore the value of LMR prognostic prediction in high-risk PTC patients.Patients and Methods: Two hundred and twenty-four PTC high-risk cases at West China Hospital were randomized into a training set (112 cases) and testing set (112 cases), while 48 cases in Shang Jin Nan Fu Hospital were included as the external validation set.Results: A lower preoperative LMR correlated with larger tumor size, advanced N and M stages, and an increased number of multiple PTC cases in the training, testing, and validation sets (all P

The World Bank’s Doing Business covers more than 190 economies. By 2019, China’s best ranking is 46. Against the background of the increasingly strong economic globalization, China’s reform must not only adapt to the national conditions, but also to the international standard, so as to create a good international reputation, attract more international investment and promote the sustained and high-speed development of the domestic economy while promoting the rapid improvement of the government’s own capabilities. Based on the assessment method and China’s coordinates of World Bank’s Doing Business as the starting point of logic analysis, this paper attempts to find out the reasons behind the ranking of China’s business environment and proposes targeted solutions based on the analysis framework of “actor-process”.

This paper presents an investigation of the feasibility of self-piercing rivet (SPR) technology for use in cold-formed steel (CFS) structures. The mechanical properties of the joints, floor trusses and prefabricated CFS composite floor modules connected by SPR and self-drilling screws (SDSs) were compared. The failure mode, bearing capacity, stiffness, ductility, ultimate deformation and other performance of CFS specimens connected with SDS and SPR were analyzed. Considering the construction method of CFS structure and the particularity of SPR connection technology, the construction feasibility of SPR connection was analyzed. The results showed that under the same condition, the stiffness and ductility of the SPR joint specimens are significantly better than those of the SDS joint specimens, the bearing capacity of the two are similar, and the ultimate mid-span deflection of the composite floor with SPR specimens is significantly greater than that with SDS specimens. It is highly feasible to use the SPR connection instead of the SDS connection for prefabricated light steel floor system with high stiffness requirements

In order to reveal the quantitative impact of multiscale on driving forces in land-use change, this paper constructs a Multiscale Regression Analysis Model (MRAM), a binary response variable Two-level Logistic Regression Model (TLRM) to explore the core driving forces, the quantitative impact relationships of multiscale. Based on the two models constructed, this paper further deeply analyzes the driving mechanism of multiscale land use change, and compares the analysis results supported by the data from 1999 to 2008 on the three-scale of Yunnan Province, Kunming City, and Yiliang County as an empirical study area. The results show that the MRAM based on scale-oriented comparison can reveal the core factors which cause land-use change at different scale levels from a more microscopic opinion, but the TLRM based on systematic viewpoint can better consider the quantitative influence of the multiscale. In addition, the results also show that the core driving factors of multiscale land use changes present a subset relationship deduced by the two models. These two analysis methods can reveal the multiscale driving mechanism of land-use change from macroscopic and microscopic respectively. This is very important to enrich the system of theory and method for study of the drive mechanism of land use changes.