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In this paper, the steel structure system of the assembled building is studied, the box modular building stiffness matrix reduction is proposed, and the calculation method of nodal stiffness matrix reduction is proposed based on the concept of nodal degrees of freedom coalescence and substructure to make full use of the repeatability of the box unit to reduce the order of the matrix equilibrium equation. Then, an engineering profile and a comparison of the calculation results of reaction spectrum analysis are carried out for the assembled steel structure system, and studies on the distribution of overturning moments between the frame and core and the distribution of shear forces between the core and the frame are carried out. Lastly, the assembled steel structure system is examined for damage analysis. The results show that the total overturning moment between the box-type modular structure and the conventional structure differs by 5979.6 kN·m and 2.67% in the X-direction and by 4694 kN·m and 2.18% in the Y-direction. The quality and safety of construction projects can be guaranteed more reliably with the help of this study.

Calcium ions (Ca2+) play crucial roles as second messengers in living cells and are associated with the onset and development of chronic brain diseases, including epilepsy. Dynamic and real‐time imaging of extracellular calcium levels ([Ca2+]ex) in the brain holds great potential for identifying disease foci. Magnetic resonance imaging (MRI) is a powerful non‐invasive tool for Ca2+ imaging with unlimited depth penetration. However, current available Ca2+ MR sensors lack the sensitivity to monitor small [Ca2+]ex alterations associated with chronic brain diseases in vivo. In this study, a highly sensitive Ca2+‐dependent T2‐T1 switchable magnetic nanosensor is reported, consisting of Ca2+‐specific ligands engineered near‐paramagnetic iron oxide nanoparticles. Surface ligand modifications can be adjusted to regulate the interaction energy between sensors and Ca2+, allowing for customizable response range and sensitivity to fulfill the in vivo imaging requirements. The optimized sensors enable non‐invasive visualization of early‐stage seizure focus in mice undergoing epilepsy. [ABSTRACT FROM AUTHOR]

Ultra‐high field (UHF) magnetic resonance imaging (MRI) has emerged as a focal point of interest in the field of cancer diagnosis. Despite the ability of current paramagnetic or superparamagnetic smart MRI contrast agents to selectively enhance tumor signals in low‐field MRI, their effectiveness at UHF remains inadequate due to inherent magnetism. Here, we report a ligand‐mediated magnetism‐conversion nanoprobe (MCNP) composed of 3‐mercaptopropionic acid ligand‐coated silver‐gadolinium bimetallic nanoparticles. The MCNP exhibits a pH‐dependent magnetism conversion from ferromagnetism to diamagnetism, facilitating tunable nanomagnetism for pH‐activatable UHF MRI. Under neutral pH, the thiolate (−S−) ligands lead to short τ′m and increased magnetization of the MCNPs. Conversely, in the acidic tumor microenvironment, the thiolate ligands are protonated and transform into thiol (−SH) ligands, resulting in prolonged τ′m and decreased magnetization of the MCNP, thereby enhancing longitudinal relaxivity (r1) values at UHF MRI. Notably, under a 9 T MRI field, the pH‐sensitive changes in Ag−S binding affinity of the MCNP lead to a remarkable (>10‐fold) r1 increase in an acidic medium (pH 5.0). In vivo studies demonstrate the capability of MCNPs to amplify MRI signal of hepatic tumors, suggesting their potential as a next‐generation UHF‐tailored smart MRI contrast agent. [ABSTRACT FROM AUTHOR]

Operative therapy for superficial esophagus carcinoma is the main way to treat the disease. Endoscopic excision of lesions in the esophagus has become an alternative to surgical treatment for patients with esophageal carcinoma. To overcome the disadvantages of endoscope mucosa excision (EMR), an endoscopic submucosal dissection (ESD) technique has been developed. Although ESD is one of the most effective methods of endoscopy in patients with digestive tract tumors, there are potential complications after surgery, including hemorrhage in the surgical area and stenosis of the esophagus. The objective of this study was to evaluate EMR versus ESD based on post‐operative hemorrhage and esophagus stenosis. All the related articles were retrieved from the e‐databases. The main results were postoperative perforation, hemorrhage, and stenosis after surgery. There were no statistically significant differences in the incidence of post‐operative wound hemorrhage (OR, 1.08; 95% CI, 0.36–3.29 p = 0.89). Similarly, there were no statistically significant differences in the rate of perforation after surgery (OR, 0.57; 95% CI, 0.17–1.95 p = 0.37). There were no statistically significant differences in the incidence of esophageal stricture after surgery (OR, 1.15; 95% CI, 0.26–5.15 p = 0.85). This analysis was different from the earlier meta‐analysis because ESD and EMR did not show any notable differences with respect to the incidence of perforation after surgery, the hemorrhage of the wound or the stenosis of the esophagus. These findings must, however, be supported by more high‐quality studies. [ABSTRACT FROM AUTHOR]

In this study, the hydrochemical characteristics of groundwater were assessed based on 64 shallow groundwater samples collected in the Guanzhong Basin, China, and the health risk of nitrate (NO3-) in drinking water was assessed. In addition, the spatial distributions of major water quality indicators were investigated, while bivariate plots, saturation index, and stable isotopes were used to reveal the processes controlling groundwater hydrogeochemistry. The results showed that groundwater in the study area was mostly fresh water. However, the maximum and average NO3– concentrations were 397.0 and 92.9 mg/L, respectively, indicating serious groundwater NO3– pollution. The percolation of contaminated river water exhibited considerable impacts on groundwater quality. Carbonate dissolution was the major process controlling the hydrochemical characteristics of groundwater, while human activities were responsible for the high concentrations of groundwater pollutants, especially NO3–. Evaporation fraction of groundwater in the study area revealed by stable hydrogen and oxygen isotopes ranged from 4 to 13% and 4 to 11%, respectively. High non-carcinogenic health risks of NO3– to adults and children were observed in about 46.88 and 75% of the collected groundwater samples, respectively. The risk value ranges were 0-6.00 and 0-14.06, with average values of 1.36 and 3.19, for adults and children, respectively. [ABSTRACT FROM AUTHOR]

Herein, a novel electrochemical sensor for glucose and hydrogen peroxide (H2O2) detection was successfully developed through the use of Cu nanoflowers (CuNFs) combined with flexible carbon cloth (CC) substrate. The 3D flower‐like CuNFs in size uniformly and firmly grow on CC substrate by a facile, scalable, one‐step hydrothermal strategy. Morphology, size and surface property of the prepared CuNFs/CC were examined by SEM, EDS and TEM, respectively. The electrochemical mechanism of CuNFs/CC for glucose and H2O2 detection was investigated by cyclic voltammetry. High electrochemical performances were displayed with amperometric i‐t curves including a wide linear range from 1.0 nM to 6.0 mM for glucose and from 1.0 μM to 36.66 mM for H2O2, respectively. Good sensitivity, repeatability, and stability, as well as anti‐interference ability, the carbon cloth‐supported CuNFs will be the promising materials for fabricating practical non‐enzymatic glucose and H2O2 sensors. [ABSTRACT FROM AUTHOR]

Copper is an attractive candidate for sensing ammonia. Here, an electrodissolution mechanism for measuring liquid-phase ammonia was developed via a novel three-dimensional rosette-like structure of copper nanoparticles (CuNPs) integrated onto carbon cloth (CuNPs/CC). A one-step hydrothermal synthetic procedure was employed to construct the metallic CuNPs with a stereo rosette-like pattern on flexible CC substrate. The morphology, composition and sensing performance of the as-prepared composite were characterised in detail. The CuNPs/CC composite showed excellent sensing performance to ammonia, which is attributed to the electrodissolution of CuNPs being promoted by ammonia to form a stabilised copper-ammonia complex. This electrochemical response occurs without the electro-oxidation of ammonia, thus avoiding the energy barrier of the N–N bond and the toxicity of N-adsorbates, which is advantageous for ammonia detection. In addition, the sensor also shows very high sensitivity to ammonia with a low detection limit, as well as good anti-interference performance, repeatability and stability. The high accuracy and precision for the quantification of ammonia concentration in a variety of real samples indicate that the CuNPs/CC composition has potential in the development of high-performance ammonia sensors. Image 1 • Novel consequences on the development of ammonia sensor. • Ideal 3D CuNPs/CC with easy preparation and good reproducibility. • A reliable electrodissolution mechanism with strong and fast response for successful application. [ABSTRACT FROM AUTHOR]

Herein, a novel electrochemical sensor for glucose and hydrogen peroxide (H2O2) detection was successfully developed through the use of Cu nanoflowers (CuNFs) combined with flexible carbon cloth (CC) substrate. The 3D flower‐like CuNFs in size uniformly and firmly grow on CC substrate by a facile, scalable, one‐step hydrothermal strategy. Morphology, size and surface property of the prepared CuNFs/CC were examined by SEM, EDS and TEM, respectively. The electrochemical mechanism of CuNFs/CC for glucose and H2O2 detection was investigated by cyclic voltammetry. High electrochemical performances were displayed with amperometric i‐t curves including a wide linear range from 1.0 nM to 6.0 mM for glucose and from 1.0 μM to 36.66 mM for H2O2, respectively. Good sensitivity, repeatability, and stability, as well as anti‐interference ability, the carbon cloth‐supported CuNFs will be the promising materials for fabricating practical non‐enzymatic glucose and H2O2 sensors. [ABSTRACT FROM AUTHOR]

Despite numerous advances in the field of nonenzymatic glucose detection, monitoring glucose in physiological applications is still a challenge and is mostly limited to electrode surface modification. This study proposes a simple method for electrodepositing cotton-like gold microspheres (CGMs) on a carbon cloth (CC) flexible electrode, with the potential for the functional supporting substrate to monitor glucose in a neutral environment. It was demonstrated that the voltammetric response of glucose oxidation increased with increases in glucose concentration in the 3D functional flexible substrate; moreover, the amperometric response of glucose oxidation increased over time. The results indicate that the functional flexible electrode—made of gold microspheres-based carbon cloth with a predefined geometry and pore-architecture network to promote the medium-permeation and synergetic effects between CGMs and CC—can be a suitable platform for measuring glucose variation in environments with neutral pH. This is particularly relevant because the oxygen-containing functional groups on the CC surface increase the dehydrogenation rate of glucose oxidation in neutral phosphate-buffered saline. [Display omitted] • The carbon cloth-supported CGMs were firstly fabricated and directly used as the flexible glucose sensor. • The flexible glucose sensor can be easily manufactured in 1 h and displayed long service life. • The CGMs/CC realized the detection of glucose under physiological conditions and successfully applied to sweat and blood. [ABSTRACT FROM AUTHOR]

While the Healthy China strategy is being implemented, the China Geological Survey has proposed and deployed a health geological survey project, starting a new journey of health geological survey and evaluation to support and serve the construction of Healthy China. However, there are still many urgent problems to be solved in this project, such as the survey vision, the framework of the evaluation indicators, the risk identification method, and the service scopes of the potential achievements. Therefore, in this paper, a framework for health geological survey and evaluation was proposed, which includes regional health geological survey zoning and local ecological risk identification. At regional scale, the framework of indicators, grading standard, score calculation, zoning method of health geological survey, identification of beneficial and harmful health geological factors, and application of achievements were proposed. These contents were presented based on the core evaluation indicators (e.g., the chemical composition, physicochemical properties, topography, and climate of the crustal surface environment caused by geological evolution processes) and the optional evaluation indicators (e.g., sanitary condition, economic level and geo-environment). At local scale, the selection of evaluation area, workflow, risk identification and the application of achievements were proposed to avoid the ecological risks of harmful trace elements and develop beneficial health geological resources. • Proposal of the framework of health geology survey and evaluation. • Presentation of regional health geological survey zoning evaluation indicator and method. • Establishment of the criterion for ecological risk evaluation at a local scale. [ABSTRACT FROM AUTHOR]