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Concrete-filled steel tube (CFST) members have been widely used in skyscrapers and long-span bridges. Non-uniformly distributed hydration heat during curing, inadequate compaction during construction and unavoidable shrinkage and creep of mass concrete in service most likely lead to interface debonding defects between concrete core and steel tube, which has been a common concern. The development of effective non-destructive inspection methods for interface bonding condition of existing CFST members is critical. In this study, an interface debonding defect detection method based on electromechanical impedance (EMI) measurement using surface-mounted piezoelectric-lead-zirconate-titanate (PZT) sensors is proposed at first. Then, experimental study on the feasibility of the proposed approach is carried out with scaled CFST specimens with artificially mimicked interface debonding defects. EMI of surface-mounted PZT sensors at different frequency bands are measured and compared to verify the detectability of the proposed approach for the mimicked interface debonding defects. Thirdly, a multi-physics CFST-PZT coupling finite element model (FEM) with interface debonding defects is established, and EMI of surface-mounted PZT sensors at different locations is simulated. The influence of interface debonding defects on EMI measurements is illustrated. Finally, a blind inspection on the interface bonding condition of selected CFST columns in an existing skyscraper in service using the proposed approach is carried out. Both bonding and debonding defect in the tested CFST columns are detected correctly and validated with drilling hole observation. Experimental, numerical and engineering application results show the proposed approach is effective for interface debonding detection of CFST members and sensitive to minor debonding defect of 0.3 mm in CFST members. [ABSTRACT FROM AUTHOR]

This article addresses social legacies or "historically remaining issues"—the impacts of Mao-era policies and practices on life courses, socioeconomic statuses, living conditions, and other aspects of social life in the post-Mao era. These social legacies involve state–society interactions on policy adjustments and symbolic practices and, therefore, are tangled up with other legacies, institutional and cultural, of the Mao years. This point is illustrated in a study of the Shanghai–Xinjiang zhiqing migration program of 1963–1966, in which about 97,000 Shanghai " zhiqing " (educated youths) were mobilized to settle in the Xinjiang Construction and Production Corps. After petitions and protests in 1979–1980, some returned to Shanghai legally, but others returned to and remained in Shanghai without documents. This article discusses how Shanghai zhiqing returnees have been petitioning and protesting to pressure the state to solve problems relating to their hukou, pensions, and healthcare, and how the state responded with repression and incremental, ad hoc policy changes, which have caused repercussions and provoked grievances. State–society interactions over the social legacies of the Shanghai–Xinjiang migration program have been constrained by related institutional and cultural legacies, including the hukou system, the status of the Xinjiang Construction and Production Corps, the state's positive historical assessment of the Shanghai–Xinjiang program, and the zhiqing's pride in and confusion over their identities. [ABSTRACT FROM AUTHOR]

Disreputable exchanges are morally disapproved and often legally prohibited exchanges that exacerbate and reproduce social inequality but remain ubiquitous. Although previous literature explains the phenomenon by material interests and structural relations, we propose a cultural approach based on three major conceptions of culture: culture in relations, culture in interactions, and culture in inequality. We illustrate this approach by a case study of China's hongbao (the red envelope) exchange, a typical disreputable exchange through informal medical payment. Drawing on interviews with doctors and patients, we find that participants of the exchange mobilize items from their cultural repertoires, such as professional ethics, face, power, fairness, and affection, to redefine different situations of interactions and project positive self–images to render their problematic exchanges morally acceptable to each other. Moreover, as the participants' responses to our vignettes show, they negatively evaluate the exchanges in general moral terms, such as equality and fairness, but culturally justify their own involvement. This discrepancy between saying and doing tends to legitimize the disreputable exchange amid enduring public outrage and institutional prohibition. These cultural processes contribute to the reproduction of unequal access to scarce health care resources. Findings of this research not only offer insights into understanding disreputable exchanges but also contribute to research on other cases of social problems in which deviant behaviors are morally and culturally justified. [ABSTRACT FROM AUTHOR]

Objective: Pathologic tumor size assessment highly depends on the gross specimen size once microscopic cancer size exceeds its macroscopic size, in particular if the dimension along the plane of sectioning is the greatest. We hypothesize that the method by which the specimen size is estimated can yield significantly different tumor size measurements and thus affect breast cancer staging and treatment. Methods: The size in the plane of sectioning of 50 lumpectomies over 4 cm was examined by 5 methods: measured grossly in the fresh state and postfixation, and calculated from the gross measurements by 3 different methods. For 15 mastectomies, we measured and calculated the span of the middle 4 and 6 slices using 3 methods. Results: For all 50 lumpectomies, fresh measurement yielded the largest size. The difference in size of lumpectomies was greater with increasing specimen size (P <.001). Using the method of adding 0.4 cm per each submitted sequential section yielded the smallest size in most cases. In mastectomies the span of the middle 4 and 6 slices was significantly larger if calculated from the average slice thickness based on the specimen size. Conclusion: The method of specimen size measurement has implications in estimation of tumor size and patient management. It is essential that pathologists be aware of the technique used and its limitations. For individual slice thickness, we highly recommend using the measurements obtained at the time of grossing rather than calculating the average slice thickness from the specimen size. [ABSTRACT FROM AUTHOR]

Determining the cable force and other parameters of cables is important for condition assessment of cable-stayed structures. This study proposes a frequency characteristic equation of transverse dynamic stiffness for cables; this equation is suitable for measuring the vibrations to evaluate the primary factors that influence the accuracy of cable parameter identification. Further, a cable parameter identification method based on the particle swarm optimization algorithm is proposed. The method is suitable for a cable system of arbitrary length and with moderate sag especially when the measurement quality of the modal frequencies of cables is poor. Both numerical case studies and a cable vibration test proved that the proposed method can identify parameters with high accuracy for cables of any length and for cases requiring low-frequency measurement. Moreover, structural modal order information is not required. The extreme case is that only one order frequency can achieve highly accurate result in this way. The proposed method is suitable for parameter identification of short cables, hanger cables, and parallel strand cables, which are commonly applicable in engineering applications. [ABSTRACT FROM AUTHOR]

The relationship between generation and memory instantiates a theme central to sociology: the intersection between history and biography. This study addresses two gaps in the literature. First, whereas the dominant approach uses a cognitive concept of memory operationalized as naming events, I focus on autobiographical memory represented in life stories, in which members of a generation understand the meanings of their personal past as part of a historical event. Second, whereas the dominant approach stresses intergenerational differences of memory, I draw on a Bourdieu-Mannheim theoretical framework to use class—including class positions and habitus—to describe and explain intragenerational differences in autobiographical memory. The two theoretical goals are achieved through theorizing an important case: the autobiographical memories of China's "sent-down youth" generation, the 17 million youths (zhiqing) sent by the state to the countryside in the 1960s and 1970s. Drawing on a qualitative and quantitative analysis of life-history interviews with 87 former zhiqing, I describe how this generation reconciles two components of autobiographical memory: personal experience in their sent-down years and historical evaluation of the send-down program. Respondents' present class positions shape their memory of the personal experience, whereas their political habitus formed in the political-class system in the Mao years molds their historical evaluations of the program. Their habitus may change as a response to the social transformation in recent decades. This article not only contributes to our understanding of generational memory but also brings class back into the field. [ABSTRACT FROM AUTHOR]

Structural nonlinearity identification is critical for post-event damage detection or condition evaluation of engineering structures after strong dynamic excitation such as earthquake where structural nonlinear behaviour should be considered. Structural nonlinear restoring force provides direct indicator describing structural damage initiation and development procedure. Considering the availability of structural dynamic response measurement and the difficulty in defining a parametric model for structural nonlinearity and in estimating structure mass accurately in practice, in this article, a time-domain structural nonlinear restoring force and mass identification approach for multi-degree-of-freedom structures under incomplete excitation using limited acceleration measurements but without using any parametric models of structural nonlinear restoring force is proposed. At first, a memory fading extended Kalman filter with a weighted globl iteration (MF-EKF-WGI) is used to identify the location of nonlinearities and then a Chebyshev polynomial nonparametric model is introduced to model the nonlinear restoring force. The unscented Kalman filter is used to identify the structural responses and the parameters of the Chebyshev polynomial to describe structural nonlinearity. Numerical and experimental studies with a four-storey frame model structure equipped with a magnetorheological damper, which is employed to mimic structural nonlinear behaviour, under impact excitations are carried out to validate the performance of the proposed approach using acceleration measurements at certain degrees of freedom. Numerical and experimental results show that the proposed approach is capable of identifying both structural nonlinear restoring force and mass with acceptable accuracy even with a very rough initial mass estimation. The proposed time-domain identification approach can be used to detect structural damage initiation and development process and to evaluate energy consumption quantitatively of engineering structures under dynamic loadings. [ABSTRACT FROM AUTHOR]

Objectives: Tracheobronchial foreign body aspiration (TFBA) is a major cause of accidental death in children. Lower respiratory tract infection (LRTI) may be caused by TFBA, but there are few reports about LRTI associated with TFBA. This study collected TFBA cases in our hospital to analyze LRTI and determine its risk factors. Methods: A total of 194 children who underwent tracheobronchial foreign body (TFB) extraction in The Children's Hospital of Zhejiang University School of Medicine from June 2019 to April 2020 were enrolled. CT chest is routinely used in the workup of suspected airway FB at our institution to evaluate for patients, a FB was already highly suspected. The retention time was defined as from the time of TFB inhalation or presentation (if there was no history of TFBA) to the time of TFB removal. General characteristics including weight, clinical symptoms, operative records, cervicothoracic CT, retention time, type of TFB and postoperative hospitalization time were collected. Chi-square tests, rank sum tests and multivariate logistic regression analyses were performed. Results: The incidence of LRTI was 46.6%, 68.6%, and 68.6% when the retention time was within 24 hours, between 24 hours and up to 1 week and more than 1 week, respectively. Postoperative hospitalization time of LRTI group was significantly longer than that of non-LRTI group. Findings for cervicothoracic CT as pneumonia, emphysema, atelectasis meant more serious clinical manifestations and the retention time was longer in the LRTI group than in the non-LRTI group. There was a positive correlation between the retention time of a TFB and LRTI in multivariate logistic regression analysis. Conclusions: The incidence of LRTI caused by TFBA is high. LRTI is association with longer postoperative hospitalization time. The TFB retention time is an independent risk factor for LRTI. If a patient presents with significant LRTI symptoms, a course of steroids and antibiotics maybe a safer approach rather than proceeding immediately with bronchoscopic removal. [ABSTRACT FROM AUTHOR]

Background: We report emergency department and inpatient amphetamine-related trends focusing on co-occurring substance use and psychiatric diagnoses at the Centre for Addiction and Mental Health, the largest mental health teaching hospital in Canada. Methods: We describe yearly trends in amphetamine-related Centre for Addiction and Mental Health emergency department visits and inpatient admissions out of all emergency department visits and inpatient admissions between 2014 and 2021, along with proportions of concurrent substance-related admissions and mental/psychotic disorders emergency department visits and inpatient admissions among amphetamine-related contacts; joinpoint regression analyses assessed changes in amphetamine-related emergency department visits and inpatient admissions. Results: Amphetamine-related emergency department visits rose from 1.5% in 2014 to 8.3% in 2021, with a peak of 9.9% in 2020. Amphetamine-related inpatient admissions rose from 2.0% to 8.8% in 2021, with a peak of 8.9% in 2020. Significant increasing trends in the percentage of amphetamine-related emergency department visits happened especially between the second and the fourth quarter of 2014 (quarterly percent change = + 71.4, P <0.01). Similarly, the percentage of amphetamine-related inpatient admissions increased mostly between the second quarter of 2014 and the third quarter of 2015 (quarterly percent change = + 32.6, P <0.01). The proportion of concurrent opioid-related contacts among amphetamine-related emergency department visits and inpatient admission increased markedly between 2014 and 2021; psychotic disorders in amphetamine-related inpatient admissions more than doubled from 2015 to 2021. Discussion: Prevalence of amphetamine use, mostly from methamphetamine, has been increasing in Toronto as have co-occurring psychiatric disorders and opioid use. Our findings highlight the need for increases in accessible efficacious treatments for complex populations with polysubstance use and co-occurring disorders. [ABSTRACT FROM AUTHOR]

Biomass-derived glycerol is emerging as a renewable, cheap and versatile feedstock for the production of a variety of chemicals and fuels. In particular, hydrogenolysis of glycerol to other value-added chemicals over heterogeneous catalysts has been extensively studied in the past few years. The most desired products arising from this process are propanediols, i.e. 1,2-propanediol and 1,3-propanediol. Both diols are important industrial chemicals, being especially well-known as monomers for the production of many useful polymers. Although hydrogenolysis of glycerol is a promising new route for the production of propanediols, the design of applicable catalysts for its industrialisation is still a great challenge. In order to guide the rational development of efficient catalysts, several possible reaction mechanisms have been proposed based on experimental and theoretical investigations. A brief review is now presented on the reaction mechanisms for the hydrogenolysis of glycerol to propanediols over heterogeneous catalysts. The possible reaction mechanisms are summarised and classified. The main characteristics and general reaction conditions for each reaction mechanism are highlighted. Furthermore, the developing prospects and future direction of research are suggested. [ABSTRACT FROM AUTHOR]

This article remedies the divide in the theory of cultural performance between contingent strategy and cultural structure by bringing scene back in. Scene fuses components of performance and links local performance to macrolevel cultural structures and historical events. I theorize two conceptual elements: scene-act ratio and event-scene link. A scene creates an emotive context that demands consistent and timely performance; features of macrolevel events shape the emotive context of the scene. The two concepts can be deployed to explain variation in performance effectiveness. The theory is illustrated in a comparative study of Chinese leaders’ empathetic performance in disasters. [ABSTRACT FROM AUTHOR]

Objectives: To identify the optimal screw configuration for internal fixation of femoral neck fractures based on anatomic analysis on radiologic imaging. Methods: 30 proximal femurs of 15 adults were constructed by CT. 3 femoral neck sections (FNS), the subcapital, medial, and the fundus, were projected on to the lateral femoral trochanteric wall. The simulated 3 screw configurations in the projection of FNS include: 2 inverted equilateral triangles symmetrised to the axis of the FNS (IET-FNS group) or the coronal axis of the proximal femur (IET-PR group) and an obtuse triangle (OT group). The distance between the screws, the distance between the centre of the FNS and the screws, and the area ratio of the triangle/FNS were calculated. Results: The projection of the FNS on to the lateral femoral trochanteric wall is displayed as a rotating forward ellipse. Measurements of distance between screws, distance between the centre of the FNS to the screws, and the area ratio of triangle/FNS were significantly larger in the OT group than in the IET-FNS and IET-PF groups (p < 0.05). The values of the 3 parameters in the IET-FNS group were also larger than those in the IET-PF group (p < 0.05). Conclusions: The obtuse triangle screw configuration displayed advantages with respect to the parameters of distance between screws, distance between the centre of FNS to screws, and the triangle area. Therefore, the obtuse triangle screw configuration may be the ideal pattern for internal fixation of femoral neck fractures (Pauwels I and II). This needs to be corroborated with biomechanics testing. [ABSTRACT FROM AUTHOR]

We examined differences in clinical profiles, predictors, and outcomes among patients with myocardial infarction (MI) with nonobstructive coronary arteries (MINOCAs) by sex. Data of 259 (132 males and 127 females) patients with MINOCA were consecutively collected. The primary clinical end point was major adverse cardiovascular events (MACE), including cardiovascular death, nonfatal MI, stroke, heart failure, and angina rehospitalization. Female patients with MINOCA were likely to be older than male patients with higher non-ST elevation myocardial infarction rate. Total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels were higher in female patients while male patients were more likely to have a smoking history, greater ST elevation myocardial infarction rate, higher diastolic blood pressure, and more alcohol use. During the 2-year follow-up, the incidence of MACE in males and females was similar (18% vs 20.2%, respectively; P =.673). The multivariable predictors of MACE in the female group were age, hypertension, and left ventricular ejection fraction (LVEF), whereas diabetes, smoking, and LVEF were multivariable predictors of MACE in the male group. In conclusion, there were differences in the clinical profiles between sexes. Clinical outcome was similar between male and female patients with MINOCA, whereas predictive risk factors varied. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has aggravated a preexisting epidemic: the opioid crisis. Much literature has shown that the circumstances imposed by COVID-19, such as social distancing regulations, medical and financial instability, and increased mental health issues, have been detrimental to those with opioid use disorder (OUD). In addition, unexpected neurological sequelae in COVID-19 patients suggest that COVID-19 compromises neuroimmunity, induces hypoxia, and causes respiratory depression, provoking similar effects as those caused by opioid exposure. Combined conditions of COVID-19 and OUD could lead to exacerbated complications. With limited human in vivo options to study these complications, we suggest that iPSC-derived brain organoid models may serve as a useful platform to investigate the physiological connection between COVID-19 and OUD. This mini-review highlights the advances of brain organoids in other neuropsychiatric and infectious diseases and suggests their potential utility for investigating OUD and COVID-19, respectively. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has aggravated a preexisting epidemic: the opioid crisis. Much literature has shown that the circumstances imposed by COVID-19, such as social distancing regulations, medical and financial instability, and increased mental health issues, have been detrimental to those with opioid use disorder (OUD). In addition, unexpected neurological sequelae in COVID-19 patients suggest that COVID-19 compromises neuroimmunity, induces hypoxia, and causes respiratory depression, provoking similar effects as those caused by opioid exposure. Combined conditions of COVID-19 and OUD could lead to exacerbated complications. With limited human in vivo options to study these complications, we suggest that iPSC-derived brain organoid models may serve as a useful platform to investigate the physiological connection between COVID-19 and OUD. This mini-review highlights the advances of brain organoids in other neuropsychiatric and infectious diseases and suggests their potential utility for investigating OUD and COVID-19, respectively. [ABSTRACT FROM AUTHOR]

By applying finite element software ANSYS/LS-DYNA, finite element models of front bulkhead and main cabin are established, which aims to assess the dynamic response of fuselage structures impacted by tire fragment under bursting mode. Besides, dynamic characteristics of the two fuselage structures impacted by tire fragment are simulated and critical damage velocities of each working condition are obtained. The results show that composite front bulkhead cannot bear the impact load of front tire fragment at the velocity of 100 m/s, but aluminum alloy front bulkhead can. Main cabin with two properties both can bear the impact loads of front and main tire fragments. When impacted by front tire fragment, critical damage velocity of front bulkhead is approximately half of that of main cabin, while critical damage velocity of aluminum alloy fuselage is larger than that of composite fuselage. However, when impacted by main tire fragment, critical damage velocity of aluminum alloy main cabin is less than that of composite main cabin. Furthermore, maximum contact pressure of composite fuselage is 3–3.3 times than that of aluminum alloy fuselage. The difference in concave deformation is not significant when impacted by front tire fragment, but the difference is great when impacted by main tire fragment. [ABSTRACT FROM AUTHOR]

There are limited studies focused on the precise mechanism of gonadotropin-releasing hormone (GnRH) secretion dysfunction after overexposure to manganese (Mn). The objective of the present study was to explore the mechanism of Mn disruption of GnRH synthesis via nuclear factor erythroid-2-related factor-2 (Nrf2)/metabotropic glutamate receptor-5 (mGluR5)/cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) signaling pathway in vitro and in vivo. Primary astrocytes were cultured and treated with different doses of Mn, tert-butylhydroquinonet (tBHQ; Nrf2 agonists), 3-[(2-methyl-4-thaizolyl) ethynyl] pyridine (MTEP; mGluR5 inhibitor), and celecoxib (COX-2 inhibitor) to measure the levels of COX-2, mGluR5, Nrf2, and Nrf2 target genes. Mice were randomly divided into 11 groups, of which included the control group, 12.5-, 25-, and 50-mg/kg MnCl2 group, dimethyl sulfoxide (DMSO) group, tBHQ control group, tBHQ pretreatment group, MTEP control group, MTEP pretreatment group, celecoxib control group, and celecoxib pretreatment group. The injection was administered every day for 2 weeks. Then, levels of GnRH, PGE2, COX-2, mGluR5, Nrf2, Nrf2 target genes, and morphological changes in the hypothalamus of mice were measured. Mn reduced protein levels of Nrf2 and mRNA expression of Nrf2 target genes and increased mGluR5, COX-2, PGE2, and GnRH levels. Meanwhile, injury-related histomorphology changes in the hypothalamus of mice were significantly present. In conclusion, excessive exposure to Mn disrupts GnRH secretion through Nrf2/mGluR5/COX-2/PGE2 signaling pathway. [ABSTRACT FROM AUTHOR]

It has been found that exposure to manganese (Mn) could induce reproductive dysfunction, but its occupational risk in male workers is unclear. This study aims to assess the association of occupational Mn exposure with reproductive hormones and semen quality in a cross-sectional study. Urinary Mn, semen quality, and reproductive hormones were explored in 84 male workers occupationally exposed to Mn and 92 referents. Multiple linear regression analyses were used to assess the relationship. Urinary Mn levels in Mn-exposed workers ranged from 0.56 to 34.25 µg/L, and the average level was 15.92 ± 8.49 µg/L. Compared with the control group, gonadotropin-releasing hormone (GnRH) levels and luteinizing hormone (LH) levels increased significantly and the levels of testosterone (TSTO) decreased significantly in the Mn-exposed group. There was a significant positive linear association between urinary Mn and GnRH and LH, while the linear association between urinary Mn and TSTO was negative. Sperm progressive motility and total motility decreased significantly in the Mn-exposed group. There was a significantly negative linear association between urinary Mn and sperm progressive motility and total motility. In conclusion, occupational Mn exposure was inversely associated with reproductive health of male workers, resulting in the abnormality of hormones secretion and decrease of sperm motility. [ABSTRACT FROM AUTHOR]

The airflow modulator, which can generate the high-intensity infrasound, is a device transferring high-pressure gas energy into acoustic energy. Based on the aerodynamic theory, an airflow modulator is designed and the equivalent throat area formulas are deduced. Approximate theory is used to investigate the maximum sound pressure level, sound power, and airflow efficiency of this airflow modulator. The working mechanisms of the infrasonic acoustic generator consisting of a modulator and a Helmholtz resonator are studied by numerical simulations. In order to carry out the experiments, a prototype device was manufactured. It is shown that from the experimental results that this device can generate a continuous infrasound pressure level of 161dB in a 6 m3 test cavity. The simulation and the experimental results are reasonably consistent and it is estimated that such a device can generate an infrasound pressure level in excess of 162dB below 3Hz. [ABSTRACT FROM AUTHOR]