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Insufficient binding selectivity of chemosensors often renders biorelevant metabolites indistinguishable by the widely used indicator displacement assay. Array-based chemosensing methods are a common workaround but require additional effort for synthesizing a chemosensor library and setting up a sensing array. Moreover, it can be very challenging to tune the inherent binding preference of macrocyclic systems such as cucurbit[n]urils (CBn) by synthetic means. Using a novel cucurbit[7]uril-dye conjugate that undergoes salt-induced adaptation, we now succeeded in distinguishing 14 bioorganic analytes from each other through the facile stepwise addition of salts. The salt-specific concentration-resolved emission provides additional information about the system at a low synthetic effort. We present a data-driven approach to translate the human-visible curve differences into intuitive pairwise difference measures. Ion mobility experiments combined with density functional theory calculations gave further insights into the binding mechanism and uncovered an unprecedented ternary complex geometry for CB7. TThis work introduces the non-selectively binding, salt-adaptive cucurbit[n]uril system for sensing applications in biofluids such as urine, saliva, and blood serum.

This study briefly introduces the basic theory of sterilization, the characteristics of ethylene oxide sterilization for medical devices and the key factors about sterilization effectiveness, analyzes and compares three methods used in the product release of medical devices sterilized by ethylene oxide: test for sterility, traditional release and parametric release, and focuses on the theoretical basis, feasibility, validation requirements, advantages and disadvantages of parametric release.

A series of tests and studies were carried out on the parameters and effects of dynamic compaction (DC) for the deep and thick collapsible loess foundation under superhigh fill in the Lishi area, Shanxi Province, China. The test results indicate that a deep collapsible loess foundation can be effectively improved utilizing DC; moreover, loess collapse is significantly eliminated within the improvement range, and the effective improvement depth can be well estimated exploiting the modified Menard formula. Additionally, after the energy level of DC exceeds 2000 kN ∙ m, the characteristic value of bearing capacity of collapsible loess foundations can surpass 300 kPa, and the deformation modulus is beyond 25 MPa. The numerical model established by ABAQUS is reliable and can provide some guidance on the design and construction of similar engineering projects.

Chemiluminescence-based detection methods offer a superior signal-to-noise ratio and are commonly adopted for biosensors. This work presents the design and implementation of a supramolecular assay based on a chemiluminescent chemosensor. Specifically, an indicator displacement assay (IDA) with the supramolecular host-guest complex of chemiluminescent phenoxy 1,2-dioxetane and cucurbit[8]uril enables the low-micromolar detection of drugs in human urine and human serum samples. Cucurbit[8]uril thereby acts as a non-surfactant chemiluminescence enhancer and a synthetic receptor. Additionally, we show that adding an equimolar amount of cucurbit[8]uril to a commercially available dioxetane used in standard enzymatic chemiluminescence immunoassays enhances the chemiluminescence by more than 15 times. Finally, we demonstrate that a chemiluminescence resonance energy transfer between a unimolecular macrocyclic cucurbit[7]uril-dye conjugate and a phenoxy 1,2-dioxetane can be utilized to detect the herbicide paraquat at a micromolar concentration in aqueous media.

Construction project schedule is to bring the completion time and the total cost into balance by allocating resources. In order to shorten the completion time and decrease the total cost as far as possible, three time-resource-cost trade-off models for construction project under uncertain environment, including expected value (E-V) model, chance-constrained (C-C) model and chance maximization (C-M) model, were built by using uncertain theory. The duration time of activities, the allocation time of material resources and human resources are considered as uncertain variables in the three models. The E-V model was to shorten the expected completion time under the chance constraint of cost. The C-C model was to obtain the minimum completion time under the chance constraints of completion time and cost. The C-M model was to maximize the chance that the completion time is not lager than the due date under the chance constraint of cost. For the convenience of calculation, the three models were changed into crisp equivalent form. A practical case study was provided to show the application process of three models and the results can be obtained by using the genetic algorithm. Finally, some extended construction project scheduling models are introduced.

Loess cracks and expands easily under the condition of drying-wetting cycles, which will seriously affect the mechanical properties of loess in geotechnical engineering applications and lead to a large number of engineering accidents. Taking the loess in Yan ’an area as the research object, the drying-wetting cycles crack experimental of compacted loess was carried out by a self-made device. The surface crack of loess samples was quantitatively analyzed by using the PCAS system, and the relationship between the surface displacement, strain, and crack evolution during the drying-wetting cycles was analyzed by the digital correlation method (DIC). The results show that loess surface crack development can be divided into three stages: slow growth stage, rapid growth stage, and sluggish development stage. The displacement and strain distribution of loess surfaces are different at different positions, and the development degree of surface cracks varies with the number of drying-wetting cycles. DIC technology can be used for rapid and nondestructive detection of the displacement field and strain field on the surface of loess samples, and dynamic display of the temporal and spatial evolution characteristics of the generation and evolution of loess cracks.

With the development of miniaturization and high density of microwave modules, package on package (POP) configuration has been widely used. Ceramic ball grid array (CBGA) solder joints provide effective microwave signal interconnection and mechanical support between high temperature co-fired ceramic (HTCC) substrates. A CBGA solder joints T/R module based on HTCC substrate is introduced in this paper. In the process of reflow sol-dering, the T/R module may fail due to HTCC substrate cracking or CBGA solder joints falling off. Therefore, the finite element thermo-mechanical coupling analysis method is used in this paper to explore the failure causes. Besides, several factors such as HTCC substrate thickness, substrate size, cavity proportion and shell material are selected for orthogonal experimental design to study the effects of the above factors on the warpage and stress of T/R module during reflow soldering, which has certain guiding significance for the production of T/R module.

According to the project non-repeatability and their implementation environment uncertainty, this paper aims to propose a new fuzzy node labelling method. The method, with a dynamic perspective, qu...

With the rapid development of integrated circuit technology, the heat flux of electronic chips has been sharply improved. Therefore, heat dissipation becomes the key technology for the safety and reliability of the electronic equipment. In addition, the electronic chips are distributed discretely and used periodically in most applications. Based these problems, the characteristics of the heat transfer performance of flow boiling in parallel channels with discrete heat source distribution are investigated by a VOF model. Meanwhile, the two-phase flow instability in parallel channels with discrete heat source distribution is analyzed based on a one-dimensional homogeneous model. The results indicate that the two-phase flow pattern in discrete heat source distribution is more complicated than that in continuous heat source distribution. It is necessary to optimize the relative position of the discrete heat sources, which will affect the heat transfer performance. In addition, compared with the continuous heat source, the flow stability of discrete heat sources is better with higher and lower inlet subcooling. With a constant sum of heating power, the greater the heating power near the outlet, the better the flow stability.

The strength deterioration of compacted loess caused by drying–wetting cycles is influenced by various factors. In this paper, the influence of dry density (ρ), drying–wetting amplitude (A), and lower bounds of drying–wetting cycles (wl) on strength deterioration of compacted loess due to drying–wetting cycles was studied through triaxial tests and environmental scanning electron microscope (ESEM). By fitting a hyperbolic function to the deterioration data, the influence of ρ, A, and wl on the maximum deterioration rate and the development speed of the deterioration of strength parameters were quantitatively analyzed. Accordingly, a compacted loess deterioration model (CLDM) that comprehensively considers the influencing factors was established. Finally, based on Python, the CLDM was applied to finite element software ABAQUS, and the stability of a loess fill slope after exposure to drying–wetting cycles was analyzed. Analysis results show that the CLDM is capable of simulating the effect of drying–wetting cycles on the stability of fill slopes.

To define the deformation of time and space during the construction of a long and deep foundation pit in collapsible loess, the field-measured data of 10 open excavation stations in Xi’an metro are analyzed statistically. The results indicate that the vertical deformation of the ground and the lateral deformation of the soldier pile caused by the excavation of a long and deep foundation pit in collapsible loess increase with time. The maximum surface subsidence decreases with the increase in stiffness (K) of the foundation pit support system, increases linearly with the excavation depth (Hw), and decreases with the increase in the aspect ratio of the foundation pit. The lateral maximum deformation value of the soldier pile decreases linearly with the increase in insertion ratio and decreases with the increase in K of the support system. The surface subsidence of the foundation pit is characterized by a “groove shape”, and the deformation of the soldier pile is characterized as the “medium convex”. These results can provide a reference for the design and construction of similar projects in loess areas, and can predict and evaluate the deformation size and safety of similar projects, which is of great significance for further understanding the deformation mechanism of deep foundation pits in loess areas, thus perfecting the design theory and preventing foundation pit accidents.

The gravity increase method (GIM) has an inherent defect that may result in an incorrectly calculated safety factor or result in a failure to obtain the expected outcome. In this study, the error source of the GIM was quantitatively analyzed through theoretical derivation to address this problem. Hence, the modified gravity increase method (MGIM), which can eliminate the error in the GIM, was developed by adding a correction factor to the friction angle during the gravity increase procedure. The MGIM was comparatively studied by applying the GIM, shear strength reduction method (SSR), and MGIM to homogeneous slope models under different dimensions, and an ACADS (Australian Computer Aided Design Society) test was introduced to validate the applicability of the MGIM to heterogeneous slopes. The analysis results proved that the MGIM does not have the inherent defect present in the GIM, and can provide accurate results in the stability analysis of both homogeneous slope and heterogeneous slopes with various slope angle and slope height. Finally, the MGIM and GIM were applied to the numerical analysis of a geotechnical centrifugal model test of a soil slope. The results indicate that the MGIM is capable of capturing the deformation and failure characteristic of geotechnical centrifugal model test of soil slopes.

Geostatic stress field procedure is the first and the most important step for the numerical simulation of geotechnical engineering, which greatly influences the simulation results. Traditional methods often fail when the model is complex. In this paper, based on finite element method (FEM) software ABAQUS, failure reasons of four commonly used methods for the geostatic stress field are studied. According to the analysis results, a new set of methods, which can provide reasonable displacement and stress field results under complex conditions, is proposed. The proposed methods follow the principle that the stress of different materials should be obtained separately to avoid stress distortion. Then, the accuracy and applicability of the proposed method are verified through a comparison study and a specific application. This study provides a theoretical basis for the method of geostatic stress field procedure under complex condition and can serve as a reference for relevant studies.

The judicial system is a major component of the political system, while judicial impartiality is a significant guarantee of social justice. Since the founding of the People’s Republic of China, especially since the reform and opening up, China has, based on its national conditions, explored establishing and continuously improving the socialist judicial system with Chinese characteristics and maintaining social justice on the basis of inheriting the outstanding achievements of traditional Chinese legal culture and drawing lessons from human civilization, making great contributions to the rule of law civilization of mankind.

Aiming at the pain points such as insufficient technical reserves and high operation and maintenance costs in the promotion of production management informatization in small and medium-sized discrete manufacturing enterprises, a multi-tenant discrete MES system architecture is proposed. From the perspective of MES functional structure, business processes and scheduling methods, it provides a solution for the development and integration of multi-tenant discrete MES. An information management process system, which centers on quality inspection and control, supports dynamic scheduling of orders, and integrats personnel management, equipment management, material management, process management and document management has been estbalished. It realizes the information monitoring and management of the entire process from product orders to delivery of finished products, helping small and medium-sized discrete manufacturing companies to achieve the purpose of traceable production quality problems and the order completion rate at a lower cost. Practice shows that the multi-tenant discrete MES has played an important role in helping small and medium-sized enterprises in the process of digitalization, networking and intelligent transformation.

The intracellular delivery of exogenous macromolecules such as functional proteins, antibodies, polysaccharides and nucleic acids into living cells for biomedical applications is of great interest. Even though great efforts have been devoted to this task, universal delivery systems that provide excellent intracellular delivery performance combined with easy cell recovery are urgently needed. Magnetic iron oxide nanoparticles show promising potential for various biomedical applications because of their advantages such as high biocompatibility and cost-effectiveness. Herein, a new facile platform for macromolecular delivery was developed based on the photothermal properties of porous magnetic iron oxide nanoparticles (P-MNPs). The near-infrared radiation (NIR) absorption behavior of P-MNPs remarkably facilitates the delivery of macromolecules into cells while maintaining high cell viability. Furthermore, the assistance of polycationic polyethylenimine improves the efficiency of DNA delivery. Most importantly, the cells could be easily recovered after macromolecular delivery by trypsinization, which is of great significance for further practical application of the delivery system. The facile and cost-effective platform proposed in this work provides a new avenue for the utilization of P-MNPs in macromolecular delivery.

A convenient and versatile approach for biofunctionalization of magnetic nanoparticles (MNPs) was developed based on supramolecular host–guest interaction. Adamantane groups were introduced on the surface of MNPs for further incorporation of specific biofunctional β-cyclodextrin derivatives, endowing MNPs with the desired bioactivity (e.g. biorecognition capability and biocidal activity).

Poly(dimethylsiloxane) (PDMS)-based microfluidic systems are gaining increasing attention due to their ease of fabrication, optical transparency and mechanical properties. However, the inherent hydrophobicity and chemical inertness of PDMS hinder its wider application in microfluidic systems. There is thus a strong need for methods for surface modification of PDMS-based microfluidic channels. In this work, oligo(ethylene glycol)methacrylate (OEGMA) and adamantane-containing OEGMA (OEGMA-Ada) were graft copolymerized on PDMS microchannel surfaces using a simple photochemical process to give PDMS-POA. OEGMA was chosen for its resistance to non-specific protein adsorption, and OEGMA-Ada was chosen for its subsequent attachment of mannose with bacteria binding affinity or biotin with avidin binding affinity. β-CD decorated with biotin (CD-B) and/or mannose (CD-M) was attached to the PDMS-POA microchannels via host–guest interactions between the adamantane and β-CD moieties. The data obtained suggest that the functions of the PDMS-POA/CD-B and PDMS-POA/CD-M microchannels with respect to biotin binding and bacterial adhesion were renewable. In addition, the biofunction of the PDMS-POA microchannels could be switched by treatment with SDS to release the CD component followed by treatment with a different β-CD derivative. Different from previous surface modification strategies for PDMS-based microfluidic channels, the combination of visible light-induced grafting and host–guest chemistry provides modified PDMS microchannels with renewable and switchable biofunctions for the detection and measurement of specific proteins and bacteria.

Non-covalent chemosensing ensembles of cucurbit[n]urils (CBn) have been widely used in proof-of-concept sensing applications, but they are prone to disintegrate in saline media, e.g. biological fluids. We show here that covalent cucurbit[7]uril–indicator dye conjugates are buffer- (10× PBS buffer) and saline-stable (up to 1.4 M NaCl) and allow for selective sensing of Parkinson's drug amantadine in human urine and saliva, where the analogous non-covalent CB7⊃dye complex is dysfunctional. The in-depth analysis of the covalent host–dye conjugates in the gas-phase, and deionized versus saline aqueous media revealed interesting structural, thermodynamic and kinetic effects that are of general interest for the design of CBn-based supramolecular chemosensors and systems. This work also introduces a novel high-affinity indicator dye for CB7 through which fundamental limitations of indicator displacement assays (IDA) were exposed, namely an impractical slow equilibration time. Unlike non-covalent CBn⊃dye reporter pairs, the conjugate chemosensors can also operate through a SN2-type guest–dye exchange mechanism, which shortens assay times and opens new avenues for tailoring analyte-selectivity., Unimolecular chemosensor shows superior stability and detection capabilities in biofluids compared to bimolecular reporter pairs.

The vibration fatigue life assessment of vehicle radar is carried out according to the random load of transportation faced by vehicle radar in service. The refined finite element model of vehicle-mounted radar in transportation state is established to investigate its inherent characteristics. Based on modal method, Frequency response analysis and random vibration analysis was carried out. Based on S-N curve and cumulative damage theory, fatigue life prediction was carried out. The results show that the fatigue damage of dangerous parts is very big. So it is suggested to improve the structure to reduce the stress concentration, use different materials in different parts, improve the processing technology to improve the strength, etc.

Tissue-engineered vascular grafts (TEVGs) have emerged as a new choice for substitution of damaged blood vessels. A passage of a new blood vessel can be regenerated through the continuous secretion of extracellular matrix of cells seeded on the TEVGs, which is not possible using conventional vascular grafts. Although great progress has been made in TEVGs technology with advances in scaffold design and cell seeding, none have been applied in clinic hitherto. This review summarized the progress of TEVGs during the recent 7 years on the basis of four major requirements of TEVGs, namely, matched mechanical properties, blood compatibility, endothelium friendliness and biodegradability, in the hope of promoting the development of TEVGs.

Cleft lip and palate transmembrane 1-like (CLPTM1L) gene rs402710 (C > T) and rs401681 (C > T) polymorphisms have been widely studied for their potential relation to cancer risk, but studies have produced conflicting results. To systematically evaluate the association between these two polymorphisms and overall cancer risk, we conducted a comprehensive meta-analysis on all relevant articles found in the PubMed and EMBASE databases published prior to May 1, 2017. There were 26 articles with 28 studies, including 30,770 cases and 34,089 controls, for the rs402710 polymorphism and 38 articles with 48 studies, including 67,849 cases and 328,226 controls, for the rs401681 polymorphism. The pooled results indicated that both rs402710 and rs401681 polymorphisms are significantly associated with decreased overall cancer risk. In our stratification analysis, a significant association of the rs402710 polymorphism with lung and bladder cancers was identified among Asian and Caucasian populations in both hospital-based and population-based studies. The rs401681 polymorphism was significantly associated with a decreased risk of lung cancer, bladder cancer, and basal cell carcinoma in Asians and in hospital-based studies. CLPTM1L gene rs402710 and rs401681 polymorphisms thus have a protective association with various types of cancer, especially lung cancer among Asians.

In slope reliability analysis, “local averaging” of the statistical soil parameters on the slope slip surface is the main factor influencing the results of the analysis. In this study, we analyzed the curvilinear local averaging of a 2-D random field by equation derivation based on random field theory and statistical analysis. By assuming a circular slip surface, the variance reduction due to curvilinear local averaging was obtained as a function of geometric characteristics of the slip surface and variance at a “point” level, and a simple reliability analysis method for homogeneous natural slope was proposed. The proposed method contains three major steps: statistical analysis of soil parameters by site tests, determination of the limit state curve using a series of deterministic finite element analyses, and the calculation of slope failure probability by integrating the probability density function corresponding to the limit state curve. A comparative analysis shows that the proposed slope reliability analysis method based on a curvilinear local averaging of a 2-D random field is reliable and efficient.

Surfaces having dynamic control of interactions at the biological system-material interface are of great scientific and technological interest. In this work, a supramolecular platform with switchable multivalent affinity was developed to efficiently capture bacteria and on-demand release captured bacteria in response to irradiation with light of different wavelengths. The system consists of a photoresponsive self-assembled monolayer containing azobenzene (Azo) groups as guest and β-cyclodextrin (β-CD)-mannose (CD-M) conjugates as host with each CD-M containing seven mannose units to display localized multivalent carbohydrates. Taking the advantage of multivalent effect of CD-M, this system exhibited high capacity and specificity for the capture of mannose-specific type 1-fimbriated bacteria. Moreover, ultraviolet (UV) light irradiation caused isomerization of the Azo groups from trans-form to cis-form, resulting in the dissociation of the host-guest Azo/CD-M inclusion complexes and localized release of the captured bacteria. The capture and release process could be repeated for multiple cycles, suggesting good reproducibility. This platform provides the basis for development of reusable biosensors and diagnostic devices for the detection and measurement of bacteria and exhibits great potential for use as a standard protocol for the on-demand switching of surface functionalities.

In recent years, the manufacturing technology of microcircuit modules has entered the era of micro-assembly. The characteristics of microcircuit module assembly, such as long manufacturing process, multi-variety, variable batch and variable orders, lead to a great difficulty in the production management of microcircuit modules, which seriously affects the operation efficiency of the production line.

In order to solve the problem of long development cycle, high development cost and poor maintenance of complex electronic equipment, and take advantages of super-realism, multi-physics, multi-disciplinary and multi-scale of digital twin technology, this paper explored the application of digital twin in life-cycle of complex electronic equipment. Firstly, the research status of digital twin technology was analyzed from two aspects of theoretical research and engineering application. The application of digital twin technology in the key stages of product life cycle, including structure design, process planning, manufacturing, assembly, operation and maintenance was explored. Then, the key technologies of digital twin for complex electronic equipment were discussed, which promotes the engineering application of digital twin. Finally, an application example of intelligent workshop for complex electronic device production was illustrated to verify the feasibility of digital twin in complex electronic equipment, and the results shown that the digital twin based production process realized scheduling optimization, logistics precise distribution and equipment online monitoring, providing an effective way for the intelligent operation of production workshop. The methods presented in this paper changed the traditional device production and processing pattern, and provided theoretical and methodological references for engineering practices of digital twin in the future.