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To investigate the technological innovation, safety, operational advantages, and clinical application value of direct percutaneous computed tomography (CT)-guided enterostomy.This retrospective study included patients who underwent direct percutaneous CT-guided enterostomy (n = 52), percutaneous endoscopic gastrojejunostomy (PEG-J, n = 39), or laparoscopic jejunostomy (n = 68) at Fujian Provincial Hospital between October 2019 and July 2021. The study indices included stoma surgery success rate, operation time, complication rate, and postoperative pain score. We concurrently analyzed the technological innovation of direct percutaneous CT-guided enterostomy and the changes in body mass index (BMI), serum albumin, prealbumin, and C-reactive protein (CRP) levels and patient-generated subjective global assessment (PG-SGA) scores after patients received 2 months of nutritional support.Direct percutaneous CT-guided enterostomy had a high success rate (100%) and low postoperative complication rate (5.77%). Compared to laparoscopic jejunostomy, direct percutaneous CT-guided enterostomy had a shorter operation time (36.92 ± 10.60) minutes, lower postoperative pain score (4.06 ± 2.02), lower anesthesia risk, and lower operative cost. The anesthetic risk for direct percutaneous CT-guided enterostomy is lower than that for PEG-J and has wider applications. After 2 months of postoperative nutritional support, patients had increased BMI, serum albumin level, and serum prealbumin level and decreased PG-SGA scores and CRP level with statistically significant differences compared to the preoperative state ( p0.05).Direct percutaneous CT-guided enterostomy is an important method of establishing an enteral nutrition therapy pathway, especially when endoscopic jejunostomy is not possible. It has a high safety profile and few complications, has unique advantages, and deserves further promotion of its application in clinical practice.

Background. The aim of this study was to explore the relationship between coagulation/fibrinolysis function and serum lipid levels in people with advanced knee osteoarthritis (KOA).Methods. From January 1st 2013 to January 1st 2018, a total of 206 patients underwent total or unicompartmental knee arthroplasty in Changzhou No.1 People’s Hospital were enrolled consecutively in this study. Baseline characteristics and preoperative laboratory indicators of patients were collected. The association between coagulation/fibrinolysis function and serum lipid levels was analyzed using Spearman correlation analysis and multiple linear regression.Results. Spearman correlation analysis revealed that coagulation/fibrinolysis function was associated with serum lipid levels, especially prothrombin time was moderately negatively correlated with Apolipoprotein-A1 (r=-0.4585, PConclusions. The results of this study showed that coagulation/fibrinolysis function was correlated with serum lipid levels in patients with advanced KOA, although the correlation may be small. It may be hypothesized that strategies for lipid control may help improve coagulation/fibrinolytic dysfunction in patients with KOA.Trial registration. This clinical study was retrospectively registered in a publicly available registry because this study was a retrospective study began in 2018. This study was approved by the Ethics Committee of the Third Affiliated Hospital of Soochow University in Jiangsu Province of China (No.CZYY2021187).

Split-dose regimens (SpDs) of 4 L of polyethylene glycol (PEG) have been established as the "gold standard" for bowel preparation; however, its use is limited by the large volumes of fluids required and sleep disturbance associated with night doses. Meanwhile, the same-day single-dose regimens (SSDs) of PEG has been recommended as an alternative; however, its superiority compared to other regimens is a matter of debate.To compare the efficacy and tolerability between SSDs and large-volume SpDs PEG for bowel preparation.We searched MEDLINE/PubMed, the Cochrane Library, RCA, EMBASE and Science Citation Index Expanded for randomized trials comparing (2 L/4 L) SSDs to large-volume (4 L/3 L) SpDs PEG-based regimens, regardless of adjuvant laxative use. The pooled analysis of relative risk ratio and mean difference was calculated for bowel cleanliness, sleep disturbance, willingness to repeat the procedure using the same preparation and adverse effects. A random effects model or fixed-effects model was chosen based on heterogeneity analysis among studies.A total of 18 studies were included. There was no statistically significant difference of adequate bowel preparation (relative risk = 0.97; 95%CI: 0.92-1.02) (14 trials), right colon Boston Bowel Preparation Scale (mean difference = 0.00; 95%CI: -0.04, 0.03) (9 trials) and right colon Ottawa Bowel Preparation Scale (mean difference = 0.04; 95%CI: -0.27, 0.34) (5 trials) between (2 L/4 L) SSDs and large-volume (4 L/3 L) SpDs, regardless of adjuvant laxative use. The pooled analysis favored the use of SSDs with less sleep disturbance (relative risk = 0.52; 95%CI: 0.40, 0.68) and lower incidence of abdominal pain (relative risk = 0.75; 95%CI: 0.62, 0.90). During subgroup analysis, patients that received low-volume (2 L) SSDs showed more willingness to repeat the procedure using the same preparation than SpDs (Regardless of adjuvant laxative use, the (2 L/4 L) SSD PEG-based arm was considered equal or better than the large-volume (≥ 3 L) SpDs PEG regimen in terms of bowel cleanliness and tolerability. Patients that received low-volume (2 L) SSDs showed more willingness to repeat the procedure using the same preparation due to the low-volume fluid requirement and less sleep disturbance.

Phytochemical investigation on the twigs and leaves of Trichilia sinensis led to the isolation of two previously undescribed limonoids (i.e., trichiliasinenoids D and E, 1 and 2), two previously undescribed phenolic acids (3 and 4), and one previously undescribed natural phenolic acid dimer (5), together with 11 known compounds (6-16). Their structures were elucidated by extensive spectroscopic analysis (IR, UV, HRESIMS, 1D and 2D NMR) and chemical techniques. The potential anti-inflammatory activities of all the compounds were evaluated in lipopolysaccharide-stimulated RAW 264.7 cells. Among these isolates, compounds 1, 2, 6, and 11-13 expressed weak NO inhibition. The antibacterial activities of all the compounds against bacteria were also tested in vitro. Compound 16 exhibited moderate antibacterial activities against Escherichia Coli.

Eleven previously uncharacterized steroids, along with three analogs were isolated from Aglaia lawii leaves. Their structures were definitely characterized by the methods of NMR, MS, IR, ECD and X-ray crystallography study. Among these unreported compounds, 3-epi-dyscusin C, 3-epi-lansisterone E and (Z)-2α-hydroxyaglawone were C-21 pregnane steroids incorporating a highly oxygenated ring A, while others were Δ5-3β-hydroxy-7-ketosteroids bearing different ring D and C-17 aliphatic chains. All isolates were evaluated for nitric oxide (NO) inhibitory activities. 3-Epi-dyscusin C, 3-epi-lansisterone E, (Z)-2α-hydroxyaglawone and 17(20)E-dyscusin B showed significant anti-inflammatory activities with IC50 values of NO inhibition less than 10 μM (in the range from 4.47 ± 0.36 to 7.67 ± 0.46 μM).

Detection of the number of vegetative cells and endospores is necessary for quality control during the production of orally administered probiotic Bacillus licheniformis-containing tablets (BCT). However, there is no standard method for the rapid detection of vegetative cells and endospores in China. In this study, a simple flow cytometry (FCM) method was used to monitor the population dynamics of BCT. Using a specific fluorescent stain, SYBR green I, flow cytometric analysis could easily differentiate two morphological states of B. licheniformis. Compared with plate count assay (PCA) for determining the number of vegetative cells and endospores, the percentage of endospores determined by FCM was ~10% higher than that by PCA. Advantages of the FCM method over conventional methods include lower labor work, shorter detection time, and higher accuracy. Therefore, this simple FCM method could be a practical tool for monitoring quality control during the production of probiotic BCT.

The particles suspended in seawater exert great influences on pollutant migration and transformation in the marine environment, and lipophilic algal toxins (LATs) enriched by these suspended particles could lead to increasing toxicity to marine filter feeders. In this study, a novel method featuring ultra–performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) was developed for the simultaneous determination of eight LATs in suspended particles. After extraction with methanol by ultrasonic–assisted extraction, the sample was separated on an Acquity UPLC BEH C 18 column (50 mm × 2.1 mm, 1.7 μm) via gradient elution using acetonitrile and water containing 5 mM ammonium acetate as the mobile phases. Qualitative and quantitative analyses were carried out by electrospray ionization MS/MS in multiple reaction monitoring mode. Under the optimal conditions, satisfactory precision (relative standard deviations, ≤ 14.1%), recoveries (83.8%–110.4%), and detection limits (2.9–103 pg g −1 ) were achieved. Good linearity ( R 2 ≥ 0.99) was also obtained for all studied analytes. The proposed method was applied to determine the amounts of the eight LATs in authentic suspended–particle samples collected from the Qingdao near–shore area in China. Pectenotoxin–2 was detected in the samples from Shilaoren beach and No. 3 bathing beach at concentrations of 717 and 790 pg g −1 , respectively.

The present study examined the interactive effects of organizational resources on classroom quality of 90 Chinese kindergartens using principal and teacher questionnaires and observational ratings of classroom practices. The results revealed that the average monthly teacher salary, child-teacher ratio and instructional management had significant direct associations with classroom quality, and the three-year average fiscal funding had a significantly positive association with instructional management and significant indirect association with classroom quality via the mediation of instructional management. The findings suggested that the allocation and organization of resources for teachers and instructional management in support of teachers and teaching are important for improving classroom quality, and that kindergarten leaders play a critical role in effectively transforming available resources into quality classroom practices.

A method based on sample preparation by accelerated solvent extraction and analysis by liquid chromatography-tandem mass spectrometry was validated and used for determination of seven typical lipophilic marine toxins (LMTs) in marine sediment samples collected from three typical coastal bays in China. Satisfactory specificity, reproducibility (RSDs ≤ 14.76%), stability (RSDs ≤ 17.37%), recovery (78.0%-109.0%), and detection limit (3.440 pg/g-61.85 pg/g) of the developed method were achieved. The results obtained from the analysis of samples from Hangzhou Bay revealed okadaic acid as the predominant LMT with concentrations ranging from 186.0 to 280.7 pg/g. Pecenotoxin-2 was quantified in sediment samples from Laizhou Bay at the concentrations from 256.4 to 944.9 pg/g. These results suggested that the proposed method was reliable for determining the typical LMTs in marine sediments and that the sediments obtained from Hangzhou Bay, Laizhou Bay and Jiaozhou Bay were all contaminated by certain amounts of LMTs.

In this study, a 4-vinylphenylboronic acid-functionalized graphene oxide (GO) material was prepared via atom-transfer radical polymerization (ATRP) method and applied for the first time as a novel matrix for the selective enrichment and analysis of small-molecule compounds with vicinal diols, which have been the focus of intense research in the field of life science, by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) in positive-ion mode. There are two main factors playing a decisive role in assisting laser D/I process comparing to some traditional matrices: (1) GO provides π-conjugated system by itself for laser absorption and energy transfer; (2) the modified 4-vinylphenylboronic acid can selectively capture small-molecule compounds with vicinal diols. The results demonstrate that the novel material has distinct advantages over previously reported matrices in enriching and assisting the highly efficient ionization of target molecules for mass spectrometry analysis. This work indicates a new application branch for graphene-based matrices and provides an alternative solution for small-molecules analysis.

Should SOEs pay a cost price for the unique advantages of the monopoly position they have and the tilting of financial policies? When it comes to national participation in profit, the benefit game relation between the state and enterprises will pose an impact on dividend benefit of nationals and sustainable development of enterprises. Since reform and opening up of China, the SOE dividend distribution has gone through several reforms. The current profit delivering ratio is lower than 30%. Depending on the nature, period and industry, the different choice regarding dividend distribution made by the state and SOEs will pose an impact on performance of the transaction cost and operation efficiency of the enterprise. Therefore, the enterprise dividend should be collected according to their categories reasonably, and the budget index should be refined to find a way to return the benefits to nationals.

The development of China's technical education has been severely constrained by the shortage of education funds. China's technical education funding are too small. The main source of education comes from fiscal revenue. A large proportion of State-owned enterprises profit income as a major source of fiscal revenue are still retained in the enterprises. We should turn over a portion of State-owned enterprises profit for technical education funding in order to alleviate insufficient technical education funds. The central government should decentralize powers to ensure the activity of local government, thus achieving the optimal coordination of benefits between the two, so as to increase the local government technical education funding. We should further refine the responsibility of all levels of government, improve the management mechanism of technical education funds. And then we should implement a comprehensive, multi-level technical education funding management mechanism.

Surface-initiated atom transfer radical polymerization was successfully used to prepare 4-vinylphenylboronic acid functionalized poly(glycidylmethacrylate-co-ethylenedimethacrylate) beads for the selective enrichment of glycoprotein from complex biological samples in this study. The modified bead surfaces were characterized using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The sorption behaviors, including adsorption isotherms, incubation time, and pH effect, were investigated. The results demonstrated that the boronated beads have a high affinity for glycoprotein, which is due to the well-defined boronic acid brushes on the beads surfaces. Furthermore, the polyvinylphenylboronic acid grafted poly(glycidylmethacrylate-co-ethylenedimethacrylate) beads were used to efficiently enrich and purify glycoprotein from real egg white samples and α-fetoprotein from human serum samples. The mass spectrometry results demonstrated that the polyvinylphenylboronic acid grafted poly(glycidylmethacrylate-co-ethylenedimethacrylate) beads are a suitable material for the enrichment of glycosylated protein from complex biological samples.

The MSD phenomenon is an active research topic of the academic and the aviation industry. This paper puts emphasis on the multi-crack propagation with interactive effects of MSD structure in 2524-T3 aluminium alloy. Material tests were accomplished for the crack growth parameters. The multi-crack propagation tests were conducted on specimens containing 5-similar-details, and the corresponding fatigue crack growth analysis with a fast prediction of crack growth life method were accomplished with finite element software. The comparison of crack tip position vs. load cycling from the test and the numerical simulation shows that the numerical simulation can give a good agreement to the experiment result.

Two new limonoids, namely 14,15-didehydroruageanin A (1) and 3-O-methyl- butyrylseneganolide A (2), were isolated from the fruits of Khaya ivorensis along with six known limonoids: seneganolide A (3), 1,3-dideacetylkhivorin (4), 7-deacetylkhivorin (5), 3-deacetylkhivorin (6), 1-deacetylkhivorin (7), and 3-deacetyl-7-oxokhivorin (8). All the compounds were evaluated for their cytotoxicity against five tumor cell lines.

The effect of the notch depth on the impact toughness of the adhesively bonded steel butt joint under Izod impact test is studied using both the finite element method and experimental method. The results obtained from numerical simulation showed that the response time with the peak stress Seqv occurred becomes little longer when the notch depth increased from 2 mm to 8 mm. And a negative longitudinal stress occurred when there is an 8 mm depth notch which might be beneficial to subject impact load. The results from the experiments showed that the effect of notch depth is evidently on the Izod impact properties. The impact energy absorbed by unit area of joint is increased as the notch depth increase

Detection of the number of vegetative cells and endospores is necessary for quality control during the production of orally administered probiotic Bacillus licheniformis-containing tablets (BCT). However, there is no standard method for the rapid detection of vegetative cells and endospores in China. In this study, a simple flow cytometry (FCM) method was used to monitor the population dynamics of BCT. Using a specific fluorescent stain, SYBR green I, flow cytometric analysis could easily differentiate two morphological states of B. licheniformis. Compared with plate count assay (PCA) for determining the number of vegetative cells and endospores, the percentage of endospores determined by FCM was ~10% higher than that by PCA. Advantages of the FCM method over conventional methods include lower labor work, shorter detection time, and higher accuracy. Therefore, this simple FCM method could be a practical tool for monitoring quality control during the production of probiotic BCT.

The effect of the adhesive thickness on the impact toughness of the adhesively bonded steel butt joint during Izod impact test and the failure procedure is studied using the finite element method software ABAQUS. The results obtained show that the time with the peak stress Seqv occurred is corresponding to the element failure. And much higher peak stress might be subjected by the element near the bottom of the joint under impact load. The failure time of the element becomes little longer when the adhesive layer thickness increased from 0.1 mm to 0.4 mm. But the peak value of the Seqv decreases and the damage limit of the strain increased evidently as the adhesive thickness increased from 0.2 mm to 0.4 mm.

The effect of metal block as the fillet on the stress distributed in weld-bonded single lap steel joint was investigated using elasto-plastic finite element method (FEM). The results from the numerical simulation showed that it is beneficial when the joints with a couple of right triangle metal block were adhered to both ends of the over lap. It is advantageous of reducing the peak stress in the adhesive layer near the ends of the lap zone in weld-bonded single lap steel joints so that the stress distribution in overlap zone was improved. The load-bearing capacity of the weld-bonded single lap steel joints may be elevated. There is no evidential difference in the effects between the steel and aluminum block.

Both normal and joggle double lap joints were numerical analyzed to get the stress distribution in mid-bondline and in adherends near the interface using the finite element method (FEM). The results from the numerical simulation show that nearly all the peak values of the stress components as well as the von Mises equivalent stress distributed in both mid-bondline and adherend near the interface of the adhesively bonded joggle double lap joint are significantly decreased to the normal one. It was pointed out that the load bearing capacity of the joggle double lap joint may be higher than that of the double lap joint for its decrease of peak stress, much evenly stress distribution in the middle part of the overlap zone so that more load can be subjected by the joggle double lap joint.

The effect of the adhesive thickness on the impact toughness of the adhesively bonded steel joint under impact loading is studied using the experimental method. The results obtained show that the impact toughness increases when the adhesive thickness increased then it decrease as the adhesive thickness increase. When the curing time is set as a constant, the higher the curing temperature is, the lower the impact toughness of the joint. The optimum thickness of the adhesive layer for the specimen of impact toughness test cured at 60 C for 1 h is 0.6 mm and it is 0.4 mm to 0.6 mm for the specimen cured 1 h at temperature of 90 C or higher than it. It is recommended using the notched specimen to decrease the testing deviation.

Rationale: Fecal microbiota transplantation (FMT) has been used in a wide variety of diseases. In this article, we reported a 46-year-old female with diabetic neuropathy (DN) achieved remission by the treatment of FMT. Patient concerns: The patient with an 8-year history of diabetes and hypertension was admitted to hospital due to sensitive pain of her right thigh and poor blood glucose control. The traditional hypoglycemic and analgesic treatment were useless to her symptoms. Diagnosis: Diabetic-induced neuropathy was considered. Interventions: This patient received twice FMTs for 3 months. Outcomes: After twice FMTs, the clinical response of patient was pleasant. The glycemic control was improved, with a remarkable relief of the symptoms of painful DN in particular. No obvious adverse effects were observed during the FMTs and follow-up observation-testing. Lessons: We proposed that FMT could be a promising treatment in patients with diabetes or diabetes-related complications like DN. FMT also appeared to be definitely safer and more tolerable than the pharmacologic treatment in patients with DN.

The influence of the fillet with different elastic modulus on the stress distributed in weld-bonded aluminum alloy single lap joint was investigated using elasto-plastic finite element method. The results show that the peak values of the stress along the mid-bondline at the points near the fillet edge were increased as the elastic modulus of the fillet increased. But at points near the both ends of the adherend in over lap zone as well as in the region of the nugget the peak stresses were decreased except longitudinal stress Sx. The peak value of Seqv decreased first, and then it increased again as the elastic modulus in fillet increased. The load-bearing capacity of the whole weld-bonded joints may be improved for the fillet with Adhesive B (825 MPa) for the relative high stress region in nugget was wider and the stress distribution in overlap zone was more uniform.

The effect of recessing on the stresses distributed along the mid-bondline in both standard single lap joints and co-axial ones were analyzed using elasto-plastic finite element method (FEM). The results obtained show that the values of the peak stresses of all the stresses distributed in the mid-bondline were changed greatly as the preformed angle in over lap zone was about 10 0 when the high elastic modulus adhesive is used. The effect of the elastic modulus level on the stress distribution (especially the peak stresses) is small in the middle part of the lap zone. When taken the stress distributed in the middle part of the lap zone into account, there is nearly no significant difference between the peel stress distributed in the standard joint and co-axial single lap joint when the adhesives with lower elastic modulus was used. It is recommended that a co-axial joint is suitable for the recessing joint made by aluminum alloy and a higher elastic modulus adhesive.

The effect of the adhesive thickness and elastic modulus on the stress distribution in the mid-bondline of the adhesively-bonded steel/steel joint under impact loading is analyzed using 3-D finite element method (FEM). The results show that the stress distributed in bondline near the interface was significantly affected by the adhesive thickness and the elastic modulus. When the thickness increased from 1 mm to 2 mm, the values of all the stress components increased evidently along the upper edge of the adhesive but decreased significantly along the lower edge near the loading face. When the elastic modulus of the adhesive was increased, all the stresses increased along either the upper or the lower edge. It is clear that the suitable thickness and the elastic modulus of the adhesive are very important when the adhesively bonded joints subjected to the impacting load.

The effect of a preformed angle in the lap zone of steel adherends on the stress distribution in adhesively bonded single lap joints was investigated using an elasto-plastic finite element analysis (FEA). The ultimate loads of the joints were determined by shear tests and the failure surfaces of the lap zone were analyzed using scanning electron microscopy (SEM). The results from the numerical simulation showed that all the peak stresses in the mid-bondline of the adhesively bonded single lap joint were reduced as the preformed deflection angle was increased from 0° to 15°. The highest value of the average ultimate load of the experimental joints occurred when the preformed angle was equal to 7° (about 64% higher than the standard one). The SEM images also indicated that the failure mode in the overlap zone of the joint changed from that of a mainly adhesion one to a mixed one as the preformed angle increased.

The stress distributed in the mid-bondline of the joints made of aluminium alloy and an epoxy adhesive was determined with the ANSYS software. The results from the FEA showed that the values of the peak stresses of the all the stress components (including the longitudinal stress Sx, the peel stress Sy, the shear stress Sxy, the 1st principal stress S1 and the von Mises equivalent stress Seqv) distributed in the mid-bondline are changed a little as the notch distance L was increased while the notch depth d was not great than 0.6mm. But the evidently changes occurred when the notch depth d was great than 0.9 mm for the stress Sx, Sy and S1 distributed in both the mid-bondline and the interface of the lap zone. When taken the stress distributed in the middle part of the lap zone into account, the peak stress at the point in the mid-bondline corresponding to the edge of the notch decreased firstly and then increased again as the notch distance L was increased from 0 mm to 8 mm. The proper geometry of the notch in the specimen was chosen by finite element analysis.

The elastic finite element analysis (FEA) and the experimental method of testing the cleavage strength of the joint were used to investigate the effect of the recessing as well as its length on the stress distribution in both the mid-bondline and the adherend near the interface along the bondline of adhesively bonded steel cleavage joint. The results from the FEA simulation showed that the peak values of the stresses distributed in the mid-bondline were nearly the same when the length of the arranged recessing was not greater than 10 mm except that the shear stress Sxy was increased a little when the length of the recessing was increased. For the normal stress Sy near the interface of the joint with a 16 mm length recessing, the peak stress in the adherend is about 49% higher than the one in the adhesive at the left edge of the joint. And it is supported with the results from the experiments that the ultimate load of the steel-to-steel cleavage joint decreased a little when the gap length was less than 10 mm.

A 3-D elastic finite element model was developed to investigate the stresses distribution of bi-adhesive bonded joints (i.e., the bond line of joints filled with two adhesives of dissimilar toughness). The effects of the loading mode on the stress distribution of joints, including the single-lap joints under tensile loading (i.e., single-lap joints) and the butt joints under cleavage loading (i.e., cleavage joints), were also studied in detail. Results showed that higher stress, distributed at the contact position of the dissimilar adhesives placed along the bond line of bi-adhesive bonded joints. Also, the maximum stress of the adhesive layer decreased when the length ratios and bonding sequence along the bond line, filled with two dissimilar adhesives, was appropriately designed. At the same time, stress convergence in the adhesive layer of bi-adhesive joints was also obviously reduced in contrast to the mono-adhesive joints. The numerical investigation shows that it is necessary to take into account th...

The 3-D elasto-plastic finite element method (FEM) was used to analyze the thermal stress in the laminated composite (SiC/6061Al) under the condition of a temperature cycling of 200 0C-30 0C- 200 0C-30 0C. The results from the FEM analysis showed that the hysteretic peak value of the von Mises equivalent stress in the substrate 6061Al was increased significantly as the temperature loading cycles processed on but it was nearly the same after the first cycle in the interface layer SiC of the laminated composite. The elastic strain in the substrate 6061Al varied within the range of -0.15% to 0.15% and the maximum plastic deformation was equal to about 0.26 %. The results also showed that the maximum normal stress Sx was increased from 32.8 MPa to 87.9 MPa after ten cycles and the work-hardening of the substrate 6061Al occurred during the stress and strain hysteresis loop.

The influence of the height and angle of the inner chamfer near the unload ends of the adherends and the elastic modulus of several adhesives on the stress distribution in the single lap joint has been investigated using both the elasto-plastic finite element analysis (FEA) and experimental methods. The results from FEA show that the peak stress in the mid-bondline decreases enormously as the adherends are chamfered with an angle of 30° and a chamfer height through full thickness on the inner side of the adherend. When the chamfer angle and the chamfer height are taken to be constant (h=H and θ=30°), the peak stresses in the fillet near the ends of the adherends decrease gradually as the elastic modulus of adhesives increases while all the peak stresses in the middle part of the overlap increase enormously except in the case of the peel stress. It is certain that the load-bearing capacities of the joints are better with a chamfer height of H and a chamfer angle of 30°. The results obtained from the numerical modeling were in compliance with the experimental tests.

The elastic finite element analysis (FEA) and the experimental method were used to investigate the effect of the gap, as well as its length, on the stress distribution in both the mid-bondline and the adherend near the interface along the lap zone of adhesively bonded aluminum double-lap joint. The values of the peak stresses distributed in the mid-bondline were increased a little when an 8 mm length gap was arranged symmetrically around the center of the lap zone. Both peak stresses and stress at the point close to the edge of the gap in the mid-bondline were increased when the gap length was increased, but the increment of the peak stresses was small when the lap length was not greater than 16 mm. The results from the FEA simulation showed that the effect of the gap length on the ultimate load of the joint was small as the gap length was increased. It is supported with the results from the experiments that the ultimate load of the aluminum double-lap joint decreased a little when the gap length was less than 12 mm.

The effect of the length and depth of a parallel slot as well as the elastic modulus of the adhesive on the stress distribution at the mid-bondline and in the adherend was investigated using the elastic finite element method. The results showed that the peak stress in mid-bondline decreased markedly when there were two of parallel slots located in the outside of the adherend, corresponding to the middle part of the lap zone and the original low stress in this zone of the joint increases. The peak stress decreased at first, and then increased again as the length of the parallel slot was increased. The stress distribution in the mid-bondline at the position corresponding to the parallel slot decreased significantly as the depth of the parallel slot was increased. The high peak stresses caused by the tensile load occurred close to the edge of the parallel slot in the adherend. Almost all the peak values of stresses at the mid-bondline increased when the elastic modulus of the adhesive was increased. The effect of the parallel slot on the peak stress at the mid-bondline with a low elastic modulus adhesive was negligible, but the peak stress decreased markedly for adhesives with a high elastic modulus.

A molecular phylogenetic analysis of Rhizoplaca melanophthalma, Rhizoplaca chrysoleuca, Rhizoplaca peltata and Rhizoplaca haydenii is presented based on the nuclear ribosomal internal transcribed spacer (ITS) regions and morphology. Rhizoplaca species were collected at 3400-3900 m in Tianshan Mountains, Xinjiang province, China. Rhizoplaca haydenii is reported for the first time in China. Maximum parsimony (MP) analysis of ITS sequences obtained from Tianshan Mountains samples and GenBank reveals that the evolution relationship of Rhizoplaca melanophthalma and Rhizoplaca chrysoleuca is closer to each other than to Rhizoplaca peltata, and Rhizoplaca haydenii showed closer relatedness to Rhizoplaca melanophthalma. When the four species groups from Tianshan Mountains were analyzed alone through the neighbour-joining (NJ) and minimum evolution method, we obtained the same result. The morphology analysis of Rhizoplaca Zopf which reveals the pruinose discs and apothecial discs of species did not show convincing evidences to prove phylogenetic relationship among Rhizoplaca species. In our study, the result further proved that Rhizoplaca should be rejected as a genus separate from Lecanora.

The normal stress distributed in the mid-bondline of the adhesively bonded joint under cleavage loading was investigated using the elastic finite element method (FEM) and the strain gauges method to reveal the real normal stresses distribution in the metal-to-metal joint while the load was increased. The results from the finite element analysis (FEA) showed that there is always a peak stress of the normal stress Sy in the mid-bondline occurred at a point close to the loading pin axis. When the load was increased from 0.5 kN to 3 kN, there was also a point located at about x = 16mm along the length of specimen where there is without any normal stress at all. The result of stress Sy from the FEA is nearly the same as that one obtained from the strain gauges method. It was also found that there was a evidently hardness change in the bonded zone of the adherend made from structural steel or pure copper, which can be used to explain the procedure of the joint and discuss the distribution model of the normal stress Sy in the joint under the cleavage loading.

The stress distribution of adhesively bonded metal/metal single lap joints under cleavage loading is analyzed using three-dimensional (3D) elastic–plastic finite element method (FEM). Results show that there exist complicated 3D stress states in cleavage joints, mainly including three-direction normal stress components, and three-direction shear stress components, the values of the latter are far less than that of the former. Moreover, a higher tensile stress exists at the left edge (i.e. near the loaded region of the joints) of adhesive layer along bondline, however, a compressive stress at the right edge (i.e. far from the loaded region of joints) along bondline. Furthermore, effects of thickness, elastic modulus and Poisson's ratios of adhesives on 3D stress state of adhesive layer of cleavage joints also have been investigated. However, observations have been made in particular on normal stress components at the interfaces, which provides useful insight into the 3D nature of the problem.

In order to understand the effects of the metal components embedded in adhesive fillets on the strength of adhesively bonded single lap joint, the failed surfaces were studied with diagrams of scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectrometer. The stress distribution along the length of the bondline of single lap steel joints was also studied with an elasto-plastic finite element analysis (FEA) model to understand its effect in the view of mechanics. The SEM images and the FT-IR spectra diagrams revealed that the failure in the interface was primarily mixture mode with fillets and they also presented the interface strength being higher and there were more polar links formed in the adhesive fillets with metal components. The result obtained from the numerical modeling is in compliance with it from experiment that the stress distributed in lap zone of the joint is gentler when a couple of steel wires embedded in fillet.

The residual stress in epoxy adhesive layer deposited on metal and other substrate at room temperature is studied. With embedded strain gauges in arranged depth of epoxy layer, the strain changes in the adhesive layer induced by the curing procedure and the changes of ambient temperature were measured to evaluate the changes of residual stress in place during a period after the curing procedure finished. The actual strain in epoxy adhesive layer from curing is used to estimate the residual stresses in it. While taking the strain obtained from the surface of the adhesive layer as free strain, the residual stress can be calculated and presented a strongly cyclic variation with a period of 24 h. The inner stress is also analyzed using the finite element method.

The effect of fillet containing metallic components on the strength of adhesively bonded single lap joints has been undertaken by alternating the shape and size of metallic components as a part of fillet or whole fillet at the end of the joints. Mild carbon steel and epoxy structural adhesive were used to prepare single lap-shear joints. Three types of steel components or fillets were embedded in the joints. Two of them were in shapes of wire and the remaining was a column in section of an isosceles right-angled triangle. After their failure, all specimens were analyzed by the electron probe microanalysis (EPMA) meter to explain the failing procedure of single lap joints. The results obtained from experiments show that the shear strength increased about 45% by embedding steel wire in the fillets. Its EPMA image also gives more fine toughness pits on the fracture surface and other tracks of adhesion failure while in the cases of fillets without metallic component or with a thorough metal column as fillets show the micro-appearance of being torn off. It is evident that the existence of the metallic component in the shape of round bars may improve the action of the fillets in the process of shear strength testing and failure.

The phenomenon of work hardening in the bonded region of steel adherends has been studied, and the effect of adherends recycling on the shear strength of a single lap joint is analyzed in this paper. The values of hardness on the surfaces of failed joints were measured after being simply treated (removing the adhesive layer by solvent) before the specimen preparation next time. Mild steel or pure copper sheet and an epoxy adhesive were used to prepare the single lap joints and the same couple of adherend pieces underwent three or four times of strength and hardness tests. The results obtained show that the evident hardness change occurred after the adherends passed their first or second strength testing and most of the points tended to increase their values of hardness as the tests were performed. It may be due to the contribution of the stress concentration during loading, and the residual stress occurred after the adherends unloading. The results obtained also show that the increase of hardness occurring in the bonded zone is greater than that on the face opposite to the bonded region. The distribution of micro-hardness was verified by the strain gauges testing method.

Surface-initiated atom transfer radical polymerization was successfully used to prepare 4-vinylphenylboronic acid functionalized poly(glycidylmethacrylate-co-ethylenedimethacrylate) beads for the selective enrichment of glycoprotein from complex biological samples in this study. The modified bead surfaces were characterized using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The sorption behaviors, including adsorption isotherms, incubation time, and pH effect, were investigated. The results demonstrated that the boronated beads have a high affinity for glycoprotein, which is due to the well-defined boronic acid brushes on the beads surfaces. Furthermore, the polyvinylphenylboronic acid grafted poly(glycidylmethacrylate-co-ethylenedimethacrylate) beads were used to efficiently enrich and purify glycoprotein from real egg white samples and α-fetoprotein from human serum samples. The mass spectrometry results demonstrated that the polyvinylphenylboronic acid grafted poly(glycidylmethacrylate-co-ethylenedimethacrylate) beads are a suitable material for the enrichment of glycosylated protein from complex biological samples.

By means of testing the shear strength with single lap joint, measuring electrical resistivity for cured products and the curing strain with strain gauges, the effect of cure parameters on the properties of HT1012 conductive adhesive filled with copper powder was investigated, and the residual stress in the conductive adhesives was also estimated. The experimental results show that the properties such as shear strength of the adhesives, electrical resistivity of products as well as the residual stress of cured HT1012 copper-filled conductive adhesive were evidently affected by curing temperature and time. The diagrams of scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) were also used to determine the properties. The higher mechanical property was achieved under the condition of curing the adhesive 3 h at 60 °C as the density of the hydrogen links or linkages existed in the adhesive was relatively higher and the lower electrical resistivity occurred at 80 °C.