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Steel frames may have an inherent ability to resist progressive collapse through alternative load-resisting mechanisms, including Vierendeel, flexural, catenary, and membrane actions. Among the columns at different positions, corner column failure caused by accidental loading is more dangerous due to the relatively few alternative load-resisting mechanisms. To evaluate the effects of infilled walls with or without openings on the progressive collapse resistance of steel frames, four two-span 2-story steel frames were tested in this study. According to the test results, the solid infilled frames achieved peak loads that were over 300% greater than those of the bare frame. Relative to the bare frame, the infilled frames with solid bricks and perforated bricks increased the deflection capacities by 15% and 29%, respectively. This result was attributed to the development of effective compressive struts in the infilled walls to partially transfer the vertical loads. Thus, premature joint failure was avoided. Moreover, the failure modes of the infilled walls changed when different types of brick were adopted. The infilled walls with solid bricks showed extensive shear sliding cracks; the infilled walls with perforated bricks were relatively intact, but the compressive corners were crushed. The partially infilled frame with a 40% opening ratio still increased the load-resisting capacity of the steel frame by 90%. In addition, the efficiencies of the compressive strut models of the infilled walls under corner column loss conditions were evaluated. Based on the calculations, the width of the equivalent compressive strut provided by current US standards is recommended. [ABSTRACT FROM AUTHOR]

To fully recognize the load-resisting mechanisms of post-tensioned concrete (PC) structures with realistic boundary conditions against disproportionate collapse, four beam-column subassemblies were extracted from a prototype building and the side columns and joints were reproduced to reflect the actual boundary condition. The parametric analysis was conducted, including location of the removed column (middle or penultimate) and strand profile (straight or parabolic). In addition, two RC counterparts were tested as a control group. Test results indicate that the unbonded post-tensioning strand (UPS) was able to enhance the structural robustness by increasing compressive arch action capacity of RC beams and developing catenary action. Compared with RC specimens, both PC specimens achieved much higher load resistance; herein, the PC specimen with straight strand profile obtained the highest load resistance due to two strands used, while the PC specimen with parabolic profile had higher deformation capacity. However, the existence of UPS increased the tensile force demand to the side column, leading to the flexural tension failure of the side column when the loss of a penultimate column was considered. Finally, an analytical study was carried out to quantify the load resistance from each dominant load-resisting mechanism. [ABSTRACT FROM AUTHOR]

The collapse of Champlain Towers South, Miami in 2021 indicated that flat slab structures in coastal regions show high risk of building collapse due to rebar corrosion. However, to date, few studies have been carried out to prevent these tragic events from happening again. Hybrid steel bars and basalt fiber reinforced polymer (BFRP) bars provide a possible solution due to their excellent corrosion resistance. Thus, in this study, an experimental study of eight large-scale composite slab-column connections is conducted to investigate the advantages of partially replacing steel bars with equal-stiffness BFRP bars to resist corrosion. Two normal reinforced concrete (RC) slab-column connections were first tested as reference specimens, together with two corroded counterparts having a target corrosion degree of 20%. Then, two composite connections with hybrid rebars were tested to investigate the advantage of replacing half of the steel bars with BFRP bars based on the equal-stiffness rule. Finally, two composite connections were reinforced by hybrid rebar and the steel rebar was corroded with a target corrosion degree of 20% to investigate the effectiveness of hybrid reinforcement to compensate for the decrease in punching shear resistance due to corrosion. The test results demonstrated that the punching shear resistance of the RC slab-column connections with tensile reinforcement ratios of 0.52% and 0.91% decreased by 19.7% to 24.3% when the real corrosion degree reached 12.8% and 18.9%, respectively. Replacement of steel rebar with BFRP bar following equal-stiffness rule resulted in slightly greater load resistance but lower ductility energy dissipation capacity. The punching shear resistance of the corroded composite slab-column connections with hybrid bars was greater than that of the corroded conventional RC slab-column connections by 18.9% to 21.5%. To consider the rebar corrosion effects in design, the accuracy of the equations from prevalent design codes was evaluated. • Slab-column connections were tested to demonstrate the effects of partially replacing steel bars by BFRP bars. • Counterparts were corroded and tested to quantify the influence of rebar corrosion and the effectiveness of the replacement scheme. • Analytical studies were conducted to quantitatively identify the failure mode and assess the accuracy of different codes equations. [ABSTRACT FROM AUTHOR]

Background: Small-bowel capsule endoscopy (SBCE) has become an increasingly utilized imaging modality for patients suspected of having small intestinal diseases. However, data regarding the role of SBCE in patients with Billroth II gastrojejunostomy are limited. The objective is to evaluate the safety and efficacy of SBCE in Billroth II gastrojejunostomy patients. Methods: We retrospectively studied patients with Billroth II gastrojejunostomy who underwent MiroCam capsule endoscopy between August 2013 and October 2019. Baseline patient characteristics; gastroscopic and SBCE findings; capsule transit time; and the occurrence of adverse events were collected and compared between groups with and without anastomotic lesions. Results: In total, 30 patients were analyzed in the study. The median age was 59 years, and 26 patients (86.7%) were men. The majority of SBCE positive findings including ulcers (10.0%), angioectasias (6.7%) and polyps (6.7%). In patients with (n = 10) and without (n = 20) anastomotic lesions, the anastomotic lesion was significantly associated with a delayed gastric transit time (GTT) (P = 0.026), but the two groups showed no significant difference in completion (P > 0.05). All patients underwent successful SBCE examinations without adverse events, except device transit into the afferent loop, where it remained for nearly 2 h, occurred in one case with anastomotic ulcers. Conclusions: This retrospective study demonstrates that SBCE is a safe and effective diagnostic tool in patients with Billroth II gastrojejunostomy with a favorable gastroscopic evaluation within 7 days prior. The frequently real-time monitoring is suggested due to the risk of retention in the afferent loop, and a delayed food intake is required when a prolonged stay in the afferent loop occurred. [ABSTRACT FROM AUTHOR]

External installation of steel braces is an effective approach to increase the lateral load resistance of steel moment-resisting frames. However, the effects of existence of steel braces on the robustness of steel moment-resisting frames to resist progressive collapse is still not clear because little study has been carried out. To fill this gap, in this paper, six multistory steel moment-resisting subframes (three bare frames and three braced frames) were fabricated and tested. Test results indicated that the specimen with reduced beam section in the connection zone performed best among three types of connections due to the guaranteed formation of plastic hinges at the location of reduced section and avoiding brittle fracture of weld at the connection. Experimental results proved that steel braces could increase the load-resisting capacity by 45.1% and 83.9% of the frame with weld connection and end plate connection, respectively. The gusset plate restricted the rotation of the plastic hinges in the second story of the braced frames with V-shaped bracing, which decreased its deformation capacity and degraded its catenary action capacity. Actually, the ultimate load of the braced frames with V-shaped bracing is only 87.5% of that of the counterpart without any braces. Because the compressive braces were severely buckled before the displacement reached 0.4% of the beam span, it had little effect on yield load but increased the initial stiffness of the bare frames. Thus, a majority of the benefits of the bracing system were attributed to the tensile braces. Moreover, the analytical results evaluated the differences in load resistance and development of load-resisting mechanisms in different stories. Furthermore, the contribution of compressive and tensile braces was decomposed individually by analytical analysis. [ABSTRACT FROM AUTHOR]

Background: Papillary thyroid carcinoma (PTC) is a rare malignancy in children and young adults (CAYA). It often presents with aggressive disease patterns and advanced stages, which are clinically distinct from those in adult patients. In this study, we sought to characterize and better understand the clinical variants of PTC in CAYA and explore the underlying mechanisms. Methods: CAYA patients (age ≤18 years) diagnosed with PTC between June 2006 and June 2018 were retrospectively recruited from five hospitals. Demographic information, pathological data, and follow-up status were recorded. Tumor samples obtained from 20 children (mean age 15.15 years) and 10 adults (mean age 38.80 years) underwent comprehensive whole transcriptome sequencing. Differentially expressed genes (DEGs), mutational landscape, and immune infiltration were analyzed. Results: A total of 217 CAYA-PTC patients (162 females and 55 males) with an average age of 14.38 ± 3.53 years (range 2–18) were included. Lymph node metastasis (LNM) was observed in 85.71%, of which 57.60% were in the lateral cervical compartment. Disease recurred in 28 of 217 (12.90%) patients with a median follow-up of 4.76 years. Multivariate logistic regression analysis revealed that age, bilateral disease, extrathyroidal extension, and coexisting Hashimoto's thyroiditis (co-HT) were independent risk factors for LNM, while co-HT was the only risk factor for recurrence. Using whole transcriptome sequencing of PTC tissues, we identified 301 DEGs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses showed that differences in immune mediators played important roles, based on the distributions of mutation frequencies, types, and expression levels between CAYA and adult patients. Based on the integrated data sets, we identified significantly mutated immune genes, cluster of differentiation 24 (CD24), coagulation factor 12 (F12), coagulation factor 5 (F5), integrin subunit alpha 3 (ITGA3), and retinoic acid early transcript 1L (RAET1L), which were then verified by immunohistochemistry. Furthermore, resting mast cells, resting natural killer cells, plasma cells, and regulatory T cells were different in the CAYA-PTC group and correlated with the expression of immune checkpoints. Conclusions: There are considerable variabilities that may contribute to the different clinical presentations between CAYA and adult PTC patients, among which the decrease in protective immune cells may be a factor. Collectively, our results add to the possible biological mechanisms involved in CAYA-PTC. [ABSTRACT FROM AUTHOR]

Top-and-seat angle connections are a conventional type of steel moment connection. However, their capacity in accommodating columns loss is rarely studied. In this study, five multistory steel moment subframes using top-and-seat angle connections were fabricated and tested to investigate their performance while subjected to various column-removal scenarios, including: (1) a middle column loss, (2) a penultimate column loss, and (3) a corner column loss. Moreover, the effects of the thickness of steel angle on load resistance were quantified. The test results indicated that load-resisting capacity increased significantly with the increase of angle thickness. In both middle column and penultimate column removal scenarios, catenary action was developed in the frames. It was also noticed that flexural action dominated the load-resisting mechanism of the frames under a corner column loss scenario. For beams in different stories, similar flexural resistance was developed. However, the beams in the first story were able to develop larger catenary action than that in the second story. It is worth noting that, for a corner column missing scenario, Vierendeel action helps to enhance the flexural action significantly. [ABSTRACT FROM AUTHOR]

Water distribution network (WDN) is one of the most essential infrastructures all over the world and ensuring water quality is always a top priority. To this end, water quality sensors are often deployed at multiple points of WDNs for real-time contamination detection and fast contamination source identification (CSI). Specifically, CSI aims to identify the location of the contamination source, together with some other variables such as the starting time and the duration. Such information is important in making an efficient plan to mitigate the contamination event. In the literature, simulation-optimisation methods, which combine simulation tools with evolutionary algorithms (EAs), show great potential in solving CSI problems. However, the application of EAs for CSI is still facing big challenges due to their high computational cost. In this paper, we propose DLGEA, a deep learning guided evolutionary algorithm to improve the efficiency by optimising the search space of EAs. Firstly, based on a large number of simulated contamination events, DLGEA trains a deep neural network (DNN) model to capture the relationship between the time series of sensor data and the contamination source nodes. Secondly, given a contamination event, DLGEA guides the initialisation and optimise the search space of EAs based on the top K contamination nodes predicated by the DNN model. Empirically, based on two benchmark WDNs, we show that DLGEA outperforms the CSI method purely based on EAs in terms of both the average topological distance and the accumulated errors between the predicted and the real contamination events. [ABSTRACT FROM AUTHOR]

In this paper, three precast concrete (PC) frames and one cast-in-situ reinforced-concrete (RC) frame were cast and tested to investigate the load-resisting mechanisms of emulative PC frames with various reinforcing details to resist progressive collapse. In the beams of PC frames, the top reinforcement was continuous without curtailment while the bottom reinforcement had different anchorage strength. Test results indicated that, in the event of middle column removal, similar to RC frame, beam action, compressive arch action (CAA), and tensile catenary action (TCA) could be developed sequentially in PC frames with emulative connections, PC frames with sufficient anchorage strength or additional bottom U-shaped bars passing through the middle joint could obtain similar level of CAA capacity as RC frame. However, they may achieve relatively lower TCA capacity due to higher bond strength between the top reinforcement and cast-in-situ topping layer in beams, owing to higher concrete strength in the topping layer, resulting in earlier fracture of the beam top reinforcements. Conversely, PC frames with insufficient anchorage could achieve comparable TCA capacity as RC frame. However, their CAA capacity was less than that of RC frames due to pulling-out failure of bottom reinforcements, preventing further development of strain hardening at beam action and CAA stages. Based on test results and analytical studies, it was found that, similar to RC frames, PC frames with emulative connections could provide sufficient rotational capacity to ensure development of tie-force as required by the design guidelines. [ABSTRACT FROM AUTHOR]

A rapid and accurate estimate of earthquake damage is a key component in a successful earthquake early warning (EEW) system. The cumulative absolute velocity (CAV) is an important and widely used parameter to measure ground motion intensity, but it cannot be correctly estimated via the traditional approach with the limited information available in typical EEW systems. Therefore, current EEW systems cannot effectively use CAV to predict earthquake damage. Herein, a CAV prediction model (DLcav) based on convolutional neural networks was proposed for EEW systems. DLcav is an end‐to‐end solution to continuously predict CAV using arriving seismic waves of increasing length and supplemented with additional auxiliary information. The effectiveness of DLcav to predict CAV was tested based on Japanese ground motion records, and the generalization ability of DLcav was assessed using the ground motion records from Chile. The results demonstrate that DLcav can rapidly predict CAV with good accuracy, which will help better estimate earthquake damage in EEW systems. [ABSTRACT FROM AUTHOR]

This paper presents the high-fidelity finite-element-based numerical models for modeling the behavior of prestressed concrete (PC) beam-column substructures to resist progressive collapse under column removal scenario. After careful calibration against data, the validated numerical models are further employed to shed light on the influence of bonded post-tensioned tendons (BPT) with a parabolic profile on the load transfer mechanisms of PC frames against progressive collapse. The effects of parameters, including initial effective prestress, profile of tendon and lateral constraint stiffness at the beam ends, are also investigated. The study shows that, due to the presence of prestressed tendons, the mobilization of compressive arch action in the beam at small deflections demands stronger lateral constraints, and the ultimate load resistance of PC beam-column substructures depends on combined catenary action from non-prestressed reinforcement and BPT at large deflections. For a given constraint stiffness, the initial effective prestress of BPT has less significant effect on the overall structural behavior. For prestressed tendon, a straight profile usually employed in structural strengthening can improve the initial structural stiffness and yield strength, but is less effective in enhancing the ultimate resistance against progressive collapse than the parabolic profile. [ABSTRACT FROM AUTHOR]

Insular cortex is a critical brain region that participates in the interoceptive sensations. Here, we combined the iDISCO + method and Fos immunostaining to confirm that the middle part of the right-side, but not the left-side, insular cortex in adult male mice is activated by intraperitoneal injection of lithium chloride. Lateralized activation of the insular cortex is also observed in adult female mice, but not in young or aged male mice. Furthermore, asymmetrical activation of the insular cortex was completely blocked when both sides of the vagal nerve are transected, whereas intravenous injection of lithium chloride has no effect on the insular activation. Combined together, these results indicate that the insular cortex unilaterally responds to aversive visceral stimuli in an age-dependent way and this process depends on the vagal afferent pathways. [ABSTRACT FROM AUTHOR]

Herein, we aimed to solve the problem of difficulty in filtering the noise components in the monitoring of strain on wind turbine blades using fiber bragg grating, a denoising method based on parameter-optimized variational mode decomposition (VMD) is proposed. This method uses the minimum envelope entropy as the fitness function and the slime mould algorithm for self-adaptive optimization to find the optimal combination of modal decomposition components K and the quadratic penalty factor α of VMD. The optimized VMD was used to decompose the strain data of wind turbine blades over time into K intrinsic mode components, and the noise mode was removed using the sample entropy to obtain the effective signal. The proposed method was compared to ensemble empirical mode decomposition and complementary ensemble empirical mode decomposition using the simulated signals and engineering data. The experimental results show that the proposed method can effectively remove noise from the strain data of wind turbine blades and has better denoising performance than the other two methods, which provides a reliable basis for analyzing the strain data of wind turbine blades. [ABSTRACT FROM AUTHOR]

Disproportionate collapse of steel frame is often an indicator of the overall behaviour of multi-storey building. The corner column failure is followed by deformation of all beams and columns above removed columns and redistribution of the load carried by the corner columns. Although several experimental studies of disproportionate collapse have been carried out after corner column loss, most of them only focused on the single-storey substructure, while inevitably ignoring the interaction between the storeys in the multi-storey frames (Vierendeel action). In this study, the performance of a two-storey substructure after corner column loss was experimentally studied and a corresponding numerical model was established utilizing LS-DYNA. FE model was validated and used to further study the effects of the proposed boundary assumptions, load redistribution of multi-bay steel frames, and number of bays and storeys on load resisting mechanisms. The results indicated that Vierendeel action is essential in resisting disproportionate collapse, with a contribution of 43% to the peak load. For a multi-storey frame with more than two storeys, the normalized load resistance of each storey is approximate. However, due to Vierendeel action, further internal force analysis indicates that the load resisting mechanisms are different in each storey. The two-storey substructures for understanding the disproportionate collapse behaviour of multi-storey steel frames under corner column loss are highly recommended by the parametric analysis. • Load resisting mechanisms of steel frames under corner column failure were assessed via numerical studies. • Vierendeel action is essential in resisting disproportionate collapse, with a contribution of over 43%. • With the number of storeys more than two, the normalized load resistance of each storey is approximated. • Load transfer mechanisms of each storey in a multi-storey frame is different due to Vierendeel action. [ABSTRACT FROM AUTHOR]

Six half-scale, single-storey, one-bay frame specimens were tested to investigate the seismic behaviour of masonry-infilled reinforced concrete (RC) frames subjected to lateral loading. The variables investigated included the type of masonry infill and the types of openings. The crack patterns, failure modes, load–displacement hysteretic loops, stiffness degradation and energy dissipation capacity are presented and discussed. It was found that the infill wall (with or without openings) significantly improved the behaviour of the RC frame. Moreover, as expected, the frames infilled with higher strength masonry performed better than those infilled with relatively low-strength masonry. It was also found that openings may be a detriment to the stability of infill walls, with a concentric window opening found to have worse effects than an eccentric door opening. An analytical model is proposed to determine the load-resisting capacity of bare frames and infilled frames with reasonable accuracy. [ABSTRACT FROM AUTHOR]

This paper aims at investigating 1/2 and 1/3 subharmonic resonances of a rotating functionally graded carbon nanotube-reinforced composite (FG-CNTRC) beam in the presence of geometric imperfections. A general function is introduced to denote three types of imperfections containing sine, global, and local modes. At first, based on the von-Kármán geometric nonlinearity assumption, the forced vibration equation is set up. Then, the Galerkin method and multiple scale method are utilized to study subharmonic resonance behaviors. Finally, coupled effects of FG-CNTRCs, rotating motion, and geometric imperfections on subharmonic resonance responses are investigated. It is found that a specific range of the excitation amplitude and frequency motivates the subharmonic resonance behavior. The coupling of geometric imperfections and geometric nonlinearities generates the 1/2 resonance phenomena, and geometric nonlinearities result in the 1/3 resonance behavior. Both the imperfection mode and amplitude can affect the resonance response and resonance regions. Moreover, in contrast with the 1/3 subharmonic resonance, geometric imperfections produce greater influence on the 1/2 subharmonic resonance. [ABSTRACT FROM AUTHOR]

Introduction: Peripheral neurotization, recently as a promising approach, has taken effect in recovering motor function after damage to a peripheral nerve root. Neural anastomosis comprised of nerve conduit and neurorrhaphy participates in the nerve reconstruction. Current literature lacks evidence supporting an individualized coaptation for rescue of locomotor loss in rat subjects with paraplegia secondary to peripheral nerve injury (PNI). Methods: This meta‐analysis intends to qualify the specificity of gap‐specific coaptation in treating a paralyzed limb following PNI. We used a highly sensitive search strategy to identify all published studies in multiple databases up to 1 May 2019. All identified trials were systematically evaluated using specific inclusion and exclusion criteria. Cochrane methodology was also applied to the results of this study. Results: Twelve studies, including 349 rat subjects, met eligibility criteria. For a medium nerve defect (0.5–3.0 cm), nerve conduit was more likely than neurorrhaphy to precipitate axon regeneration and improve motor outcome of the hemiplegic limb (OR = 3.61, 95% CI = 1.80, 7.26, p <.0003) at 3‐month follow‐up, whereas neurorrhaphy might take its place in promoting limb motor function in a small nerve gap (<0.5 cm) (OR = 0.48, 95% CI = 0.22, 1.07, p <.007). For a small nerve defect, nerve conduit still demonstrated visible effectiveness in recovery of limb motion albeit poorer than neurorrhaphy (OR = 1.50, 95% CI = 0.92, 2.47, p <.05). Conclusion: Selective neurotization facilitates motor regeneration after nerve transection, and advisable choice of neural coaptation can maximize functional outcome on an individual basis. [ABSTRACT FROM AUTHOR]

During the construction of suspension bridges, the stress state of the pylon (tower) is improved by pushing the pylon saddle by an appropriate distance at the proper time. An analytical algorithm for the assessment of the required timing and displacements for the pylon saddle pushing at particular construction stages is proposed and verified in this study. The timing calculation is based on the assessment of current hanger tensile forces at each construction stage and the pylon stress state, while the pushing distance/displacement is derived from the conditions of elevation difference closure and the conservation of unstrained length of the main cable segments. This algorithm was successfully applied during the construction of a particular suspension bridge in China with a main span of 730 m. The results obtained strongly indicate that the bending moment in the pylon bottom is contributed by both horizontal and vertical forces of the main cable. The horizontal constituent is dominant and its share gradually increases in the bridge construction process. In a suspension bridge with side spans of various lengths, the stresses in the pylon bottom on the side with a larger side span is more likely to exceed the limit. Therefore, the respective strength criterion controls the pylon saddle-pushing schedule. The proposed analytical algorithm is quite straightforward and is recommended for wider application. [ABSTRACT FROM AUTHOR]

Porcine bocavirus (PBoV), which belongs the genus Bocaparvovirus, has been identified throughout the world. However, serological methods for detecting anti-PBoV antibodies are presently limited. In the present study, an indirect enzyme-linked immunosorbent assay (PBoV-rNP1 ELISA) based on a recombinant form of nucleoprotein 1 (NP1) of PBoV was established for investigating the seroprevalence of PBoV in 2025 serum specimens collected in north-central China from 2016 to 2018, and 42.3% of the samples tested positive for anti-PBoV IgG antibodies, indicating that the seroprevalence of PBoV is high in pig populations in China. [ABSTRACT FROM AUTHOR]

CdSe@CdS@TiO2 microsheet array (MSA) ternary core–shell heterojunctions were prepared by successive electrodeposition of CdS and CdSe onto TiO2 microsheets using cyclic voltammetry. The photoelectrochemical performance of CdSe@CdS@TiO2 MSAs ternary core–shell heterojunctions is significantly improved. This structure not only greatly enhances the utilization efficiency of visible light but also greatly extends the spatial separation of photoinduced charge. This is because CdSe@CdS@TiO2 MSAs ternary core–shell heterojunctions have an inherent cascade energy band structure and a high-quality contact between each other at the interface. After annealing, CdSe@CdS@TiO2 MSAs ternary core–shell heterojunctions show a further improved photoelectrochemical performance because the formation of ternary compound CdS1−xSex enhances the quality of the contact interface between CdSe and CdS layers and consequently increases the transportation efficiency of photoinduced charges and injection efficiency of photoinduced electrons to the TiO2 layer. The maximum photocurrent density of 3.5 mA/cm2 was observed in the CdSe@CdS@TiO2 MSAs ternary core–shell heterojunctions after annealing at 350 °C, which is 9.46, 3.18 and 2 times higher than that observed in CdS@TiO2 MSA, CdSe@TiO2 MSA, and as-prepared CdSe@CdS@TiO2 MSA photoelectrodes, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The work provides a method on the basis of flow cytometry to evaluate the performance of denitrification biofilm during the preservation, reactivation and pilot-scale operation process. The viable cell ratio of denitrification biofilm significantly reduced and further led to the decrease of denitrification capacity after long-term preservation for 5 months. Protein component in tightly bound extracellular polymeric substances (TB-EPS) could serve to enhance microbial adhesion and promote denitrification biofilm formation. With the significant correlation of viable cell ratio and microbial characteristics, 4 °C was more appropriate for preserving denitrification biofilm and conducive to maintain the relatively high denitrification capacity. A maximum denitrification rate of 5.80 gNO 3 --N/m2·d was obtained in pilot-scale anoxic-oxic (AO) process and Dechloromonas became greater prevalence in denitrification suspended carriers. Furthermore, the enrichment of Pseudomonas , Parcubacteria , Acidovorax , Aquabacterium and Unclassified_Flavobacteriaceae enhanced biofilm formation and nutrient conservation. The significantly positive correlation between viable cell ratio and the ratio of nitrate reduction to COD consumption was discovered, and the indices of Chao, ACE, Shannon and Simpson of denitrification biofilm were positively correlated with viable cell ratio, meaning that flow cytometry analysis was reasonable and suitable to evaluate the performances of denitrification biofilm. Graphical abstract Image 1 Highlights • Flow cytometry was reasonable and suitable to evaluate the performances of denitrification biofilm. • 4 °C was in favor of storing the denitrification suspended carriers. • Protein in TB-EPS could enhance microbial adhesion and promote denitrification biofilm formation. • Significantly positive correlation between viable cell ratio and microbial characteristics was discovered. • Dechloromonas accounted for 27.6% and became greater prevalence in denitrification biofilm. [ABSTRACT FROM AUTHOR]

Background and Aims. Intestinal ultrasound (IUS) is considered a nonirradiating, noninvasive, well-tolerated, and valuable tool for objectively assessing Crohn's disease (CD) activity. However, there is no widely accepted intestinal ultrasound scoring system. This study is aimed at evaluating the efficacy of IUS key parameters, the International Bowel Ultrasound Activity Score (IBUS-SAS), and IBUS-SAS combined with blood inflammatory markers in assessing CD activity. Methods. 40 CD patients were reviewed in this retrospective study and were divided into the moderate-severe group (n = 25) and nonmoderate-severe group (n = 15) based on a simplified endoscopic score of Crohn's disease (SES-CD). Double-balloon enteroscopy/colonoscopy were reviewed by three gastroenterologists. A transabdominal ultrasound was performed by two ultrasound specialists. Blood inflammatory markers were measured from morning samples. Results. In evaluating moderate to severe CD patients, (1) IBUS-SAS had a good predictive effect with an area-under-the-curve (AUC) of 0.855 (P < 0.001); (2) IUS key parameters (including BWT, CDS, BWS, and I-fat) yielded good predictive effects with AUC of 0.811, 0.731, 0.724, and 0.747, respectively (P < 0.001); (3) blood inflammatory markers (including ESR, CRP, PLR, MLR, and NLR) also had good predictive effects with AUC of 0.771, 0.837, 0.728, 0.743, and 0.775, respectively (P < 0.001); (4) IBUS-SAS combined with ESR and CRP exerted the best predictive effect with the highest AUC of 0.912 (95% CI: 0.823-1.000), and the sensitivity and specificity were 88.0% and 80.0%, respectively (P < 0.001). Conclusion. IBUS-SAS combined with ESR and CRP is a more efficient tool than IBUS-SAS alone or inflammatory markers alone in evaluating CD patients with moderate to severe disease activity. [ABSTRACT FROM AUTHOR]

The increasing scale of modern chemical plants keeps popularizing investigation as well as application of distributed process monitoring approaches. With a goal of directly quantifying the normal relations between different blocks divided from the whole process, a novel multi‐block modeling strategy called block‐wise residual generator is proposed, which trains a residual generator for each block through using the partial least squares algorithm with single one output, so that the relation between the corresponding block and the others is quantified as a regression model in a block‐wise manner. The deviations caused by the abnormal samples to the normal relations quantified for different blocks could thus be efficiently captured by the residuals generated from the block regression models, which then provide sensitive information for fault detection and contribution‐based fault diagnosis. Moreover, the proposed method is applicable for both disjoint and overlapped block divisions, and the direct consideration of individually quantifying relations between different blocks can always guarantee its salient monitoring performance, as validated through comparisons with classical distributed process monitoring methods. A novel block‐wise residual generator (BWRG)‐based approach is proposed for distributed process monitoring. The training of BWRG is targeted to quantify the relation between different blocks in a block‐wise manner. The comparisons validated the salient superiority and consistent effectiveness of BWRG in distributed statistical process monitoring. [ABSTRACT FROM AUTHOR]

Abstract: Rotaxane‐based molecular shuttles are often operated using low‐symmetry axles and changing the states of the binding stations. A molecular shuttle capable of directional shuttling of an acid‐responsive cone‐like macrocycle on a single‐state symmetric dumbbell axle is now presented. The axle contains three binding stations: one symmetric di(quaternary ammonium) station and two nonsymmetric phenyl triazole stations arranged in opposite orientations. Upon addition of an acid, the protonated macrocycle shuttles from the di(quaternary ammonium) station to the phenyl triazole binding station closer to its butyl groups. This directional shuttling presumably originates from charge repulsion and an orientational binding preference between the cone‐like cavity and the nonsymmetric phenyl triazole station. This mechanism for achieving directional shuttling by manipulating only the wheels instead of the tracks is new for artificial molecular machines. [ABSTRACT FROM AUTHOR]

Abstract: Rotaxane‐based molecular shuttles are often operated using low‐symmetry axles and changing the states of the binding stations. A molecular shuttle capable of directional shuttling of an acid‐responsive cone‐like macrocycle on a single‐state symmetric dumbbell axle is now presented. The axle contains three binding stations: one symmetric di(quaternary ammonium) station and two nonsymmetric phenyl triazole stations arranged in opposite orientations. Upon addition of an acid, the protonated macrocycle shuttles from the di(quaternary ammonium) station to the phenyl triazole binding station closer to its butyl groups. This directional shuttling presumably originates from charge repulsion and an orientational binding preference between the cone‐like cavity and the nonsymmetric phenyl triazole station. This mechanism for achieving directional shuttling by manipulating only the wheels instead of the tracks is new for artificial molecular machines. [ABSTRACT FROM AUTHOR]

Two kinds of noise-like pulse bunches are observed in an erbium-doped fiber ring laser for the first time. Picosecond- and submicrosecond-scale pulse bunches with energy of 0.32 nJ and 7.1 nJ, respectively, are generated and used in super-continuum generation. Using a 50-m dispersion-shifted fiber (DSF) a 20-dB bandwidth of over 750 nm is obtained. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the role and mechanism of microRNA-539 (miR-539) in rheumatoid arthritis (RA). A total of 68 RA patients and 46 osteoarthritis patients were enrolled into the current study. Peripheral blood and joint fluid were collected prior to treatment. Reverse transcription‑quantitative polymerase chain reaction was performed to detect osteopontin (OPN) mRNA and miR‑539 expression levels, while ELISA and western blot analysis were applied to detect OPN protein expression. In addition, bioinformatics analysis predicted that miR‑539 directly targeted OPN, while dual‑luciferase assay was used to validate this finding. Furthermore, agomiR‑539 transfection and OPN knockdown by siRNA were conducted in MH7A cells, and MTT assay was used to detect MH7A cell proliferation. The results indicated that OPN was significantly increased in the blood and joint fluid of RA patients, while miR‑539 expression was significantly decreased in the two types of specimens (P<0.05). Subsequent to silencing OPN by siRNA, the proliferation of MH7A cells was decreased (P<0.05). Following upregulation of miR‑539, OPN expression was significantly decreased and cell proliferation was inhibited. Dual‑luciferase assay revealed that miR‑539 regulated OPN expression through complementary binding to 3'‑untranslated region. OPN was also significantly increased in the blood and joint fluid of RA patients, which may be associated with the downregulation of miR‑539. Thus, miR‑539 may promote the development and progression of RA through regulating OPN. [ABSTRACT FROM AUTHOR]

Male plants and fertile populations ofAscidiota blepharophyllaC.Massal. from Wanglang National Nature Reserve of Sichuan Province in China have been discovered recently. Here we present a description and illustrations of the androecia and sporophytes, and comment on the conservation status of this species. [ABSTRACT FROM PUBLISHER]

With the increasingly real threat of terrorism around the world, many iconic and important buildings may become targets of terrorist attack. This can lead to severe casualties and economic losses as such extreme loading events are not considered in conventional building design. However, experience from past events has shown that most well designed structures will not completely collapse immediately upon the loss of one or more columns as in cases of sabotage. As such, the residual load resisting capacity is crucial in post damage situations where engineers have to make a decision of whether to rehabilitate or rebuild the damaged building. To better understand the behavior of such damaged structures, a series of tests are conducted in this present study. The dynamic response of the specimens is assessed through dynamic tests. Following dynamic tests, the specimens, which have suffered different degrees of damage, are re-tested by push-down loading regimes to capture their residual behavior. The experimental and analytical results indicated that the damage caused by the dynamic response will significantly degrade the initial stiffness and detriment the efficiency of compressive arch action and compressive membrane action even if the specimens actually only experience elastically dynamic response. However, when the specimens undergo a considerable plastically dynamic response, no compressive arch action and compressive membrane action are able to develop. The load resisting capacity would derive mainly from tensile membrane action and catenary action in large deformation stage. [ABSTRACT FROM AUTHOR]

Background: The aim of this meta-analysis and systematic review of published evidence was to optimize chest tube management for fast-track rehabilitation of lung cancer patients after video-assisted thoracic surgery (VATS). Methods: The PubMed, Web of Science, and EMBASE databases were searched to identify all studies that addressed the issue of chest tube management after VATS for lung cancer. Finally, 35 articles were included for analysis, i.e., 29 randomized controlled trials and 6 clinical trials. Results: After synthesis of the published evidence, the following protocol for chest tube drainage was formulated: (1) after VATS lung wedge resection, chest tube drainage can be omitted in selected cases; (2) normally, one 28Fr chest tube (or 19Fr Blake drain) is placed; (3) the use of a digital monitoring system is recommended; (4) in case of increasing pneumothorax or severe air leakage supported by digital recording system, the tube should be placed with active suction; and (5) the chest tube can be removed within 48 h postoperatively when air leakage is resolved and fluid drainage is <400 mL/day. Conclusions: Further multicenter studies are warranted based on the variations of body sizes among different ethnicities. [ABSTRACT FROM AUTHOR]

Two series of experimental tests on reinforced concrete (RC) squat walls with irregular openings were analysed. The experimental evidence indicated that flanges significantly affect the failure modes, initial stiffness, ultimate strength and deformation capacity. Given the complexity of the stress distribution in walls with irregular openings, strut-and-tie models are generally used in design and analysis to explicitly demonstrate the shear force transfer and load distribution paths. A comparison of experimental data with analytical results from the existing strut-and-tie model indicated that the latter may underestimate the ultimate strength by 51%. Although the strut-and-tie model is a lower-bound solution, the underestimation of 51% is still very large and may lead to unfavourable shear failure. An improved strut-and-tie model was thus developed, based on test observations. The improved strut-and-tie model can provide a more accurate prediction for the ultimate strength of walls with irregular openings. Based on the model, design recommendations and suggestions for reinforcement details in RC walls with irregular openings are also presented. [ABSTRACT FROM AUTHOR]

A one-pot, three-component reaction of aromatic aldehydes, 2-hydroxy-1,4-naphthoquinone, and 3,4-methylenedioxyphenol has been reported for the synthesis of novel 7-aryl-6H-benzo[h][1,3]dioxolo[4,5-b]xanthene-5,6(7H)-diones using environmentally benevolentpara-toluene sulfonic acid (p-TSA) as the catalyst. This methodology provides a mild and fast route to diverse pyran derivatives in moderate to good yields. [ABSTRACT FROM PUBLISHER]

We proposed a new approach to tunable slow and fast light using double-Lorentzian active fiber Bragg gratings (DL-AFBGs). Group delay in DL-AFBGs is theoretically analyzed using the coupled mode theory. Unique double-Lorentzian spectral resonance of the proposed DL-AFBGs significantly modifies the dispersion of injected light near the Bragg frequency, leading to structure-based tunable slow and fast light. The Bragg frequency varies with the pump power of the FBG. In this way, the group delay of the signal can be optical controlled. Furthermore, we describe a possible realization of group delay tuning from subluminal to superluminal pulse reflection in active double-Lorentzian Bragg gratings. Tunable group delay from 242 ps to −200 ps is theoretically demonstrated. It provides a very simple approach to getting both subluminal and superluminal reflection in one component, which we might find a good future in light matter interaction enhancement, high sensitivity sensor and so on. [ABSTRACT FROM AUTHOR]

With the rise of the concept of metaverse and the development of virtual reality (VR), the effect of 3D audio has become an important factor which influences the immersive experience. Considering the widely used binaural 3D audio, it's important to evaluate the quality as different representation methods exist. However, there's no reference stimulus when evaluating binaural 3D audio, making it difficult to compare different representation methods. This paper proposes a multi-attribute evaluation method on binaural 3D audio without reference stimulus. Through this method, a comparative experiment with channel-based, scene-based, and object-based binaural 3D audios was conducted. The results prove that binaural 3D audios of these three representation methods are similar in audio quality, but differ greatly in spatial sense, giving a solid data support to the feature comparison of channel-based, scene-based, and object-based methods. It is also proved that the evaluation method is valid through statistical analysis and can be used in other test requirements of binaural 3D audio. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (hBN), which is a 2D layered dielectric material, sometimes referred as 'white graphene' due to its structural similarity with graphene, has attracted much attention due to its fascinating physical properties. Here, for the first time the use of chemical vapor deposition -grown hBN films to fabricate ultrathin (≈3 nm) flexible hBN-based resistive switching memory device is reported, and the switching mechanism through conductive atomic force microscopy and ex situ transmission electron microscopy is studied. The hBN-based resistive memory exhibits reproducible switching endurance, long retention time, and the capability to operate under extreme bending conditions. Contrary to the conventional electrochemical metallization theory, the conductive filament is found to commence its growth from the anode to cathode. This work provides an important step for broadening and deepening the understanding on the switching mechanism in filament-based resistive memories and propels the 2D material application in the resistive memory in future computing systems. [ABSTRACT FROM AUTHOR]

A green and convenient synthetic method has been described for the synthesis of 2-hydroxy-3-((5-methyl-3-oxo-2-phenyl-2,3-dihydro-1 H -pyrazol-4-yl)(phenyl)methyl)naphthalene-1,4-dione derivatives by a one-pot, four-component reaction of aromatic aldehydes, 2-hydroxy-1,4-naphthoquinone, hydrazine derivatives, and ethyl acetoacetate catalyzed by MgCl 2 in ethylene glycol. Simplicity, short reaction time, high yield, and an eco-friendly catalyst are the main advantages of this method. [ABSTRACT FROM AUTHOR]

A series of six one-third scaled reinforced concrete (RC) structural walls with irregular or regular openings were tested to investigate the effects of size, arrangement, and irregularities of the openings on the seismic behaviour of RC walls. The crack pattern development, failure mechanism, and hysteretic responses of tested specimens are presented. The stiffness deterioration and equivalent hysteretic damping (energy absorption capacity) of tested specimens are compared and discussed. Another series of six rectangular walls with openings, which are tested by Yanez et al., are also introduced for quantification of the flange effects on seismic behaviour of RC walls with openings. It is found that flanges could significantly increase ultimate strength but reduce deformation capacities. Moreover, flanges may change the failure mode of rectangular walls from ductile flexural failure to brittle sliding shear failure. Flanges may aggravate the concrete crushing, spalling as well as buckling and fracture of vertical reinforcements. However, concrete crushing and rebar fracture is mainly concentrated in the flanges. [ABSTRACT FROM AUTHOR]

Background Reported studies have showed that Thrombin Activatable Fibrinolysis Inhibitor (TAFI) may be associated with an increased risk of venous thromboembolism. But the relation of VT with TAFI gene SNPs could not be clearly demonstrated. Thus, we conducted a meta-analysis to analyze the associations between three TAFI variants − 438G/A, 505G/A and 1040C/T and the risk of venous thrombosis. Methods We carried out a systematic search to obtain all the eligible studies published before 30th October 2014. Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were computed to assess the association. Results 13 eligible studies were enrolled including 2321 patients and 2464 controls. There was a significant association between 505G/A and the risk of VTD under all models except recessive model (G vs. A: OR = 1.13, 95% CI: 1.02, 1.26; GG vs. AA:OR = 1.47, 95% CI: 1.14, 1.88; GA vs. AA: OR = 1.36, 95% CI: 1.06, 1.73; GG + GA vs. AA: OR = 1.41, 95% CI: 1.12, 1.77). Similarly, obvious relationship was observed in subgroup analyses in light of type of disease and ethnicity. Likewise, for 1040C/T variant, significant associations were identified under homozygote, heterozygote and dominant models (CC vs. TT: OR = 1.65, 95% CI: 1.06, 2.59; CT vs. TT: OR = 1.55, 95% CI: 1.19, 2.03; CC + CT vs. TT: OR = 1.55, 95% CI: 1.20, 2.00). Sub-analysis presented significant associations in non-CVT and non-Asian group under homozygote, heterozygote, and dominant models and CVT group in recessive model. Conclusion This meta-analysis showed that − 438G/A variant was not associated with the incidence of venous thrombosis. But in non-Asian populations, G allele and GG genotype of 505G/A may increase the risk of venous thrombosis diseases. GG genotype of 505G/A and one C carrier (CC and CT) of 1040C/T gave rise to the development of venous thrombosis diseases except CVT. Additionally, the heterozygote CT may be a potential contributing factor of gene effect in venous thrombosis. [ABSTRACT FROM AUTHOR]

Glucagon-like peptide-1 (GLP-1) was a potential therapeutic drug for type II diabetes, mainly because of the stimulatory effect on insulin secretion under condition of high blood glucose. We used PCR to obtain a recombination gene, GGH, in which two GLP-1 (GLP-1A2G) mutants were connected in series and then fused to the N terminal of human serum albumin. The fusion gene was inserted into pGAPZaA plasmid with Saccharomyces cerevisiae α-factor secretion signal sequence, and was expressed by the glyceraldehyde-3-phosphate dehydrogenase (GAP) promoter. The engineered strain was constructed by integrating the recombinant plasmid pGAPZαA/GGH into the genome of Pichia pastoris GS115. Genome PCR and western blot showed that the recombinant P. pastoris successfully expressed the fusion protein GGH. The yield of GGH reached 78 mg/L after 72 h fermentation in a flask, using glucose as the optimal carbon source. Fed-batch fermentation was investigated in a 5 L bioreactor, and the expression level of GGH reached 246 mg/L in 52 h. The fusion protein GGH was purified in four steps, and the final purity was 96.1%. The in vitro bioactivity of GGH was the same as that expressed in P. pastoris by the AOX1 promoter. This study described an efficient way to express GGH fusion protein in P. pastoris using GAP promoter, fermentation was easier to control without carbon source change and fermentation time was 20 h less than AOX1 promotercontrolled GGH fermentation. [ABSTRACT FROM AUTHOR]

For reinforced concrete flat slab structures, column failure due to unexpected extreme loading may significantly increase the moment and shear force at adjacent slab-column connections, which can trigger punching shear failure at these connections and result in progressive collapse of flat slab structures. To determine the possible load-resisting mechanisms developed in flat slab structures in resisting progressive collapse, three multi-panel flat slab substructures are tested in this study. A flat slab substructure is tested as a control specimen. The remaining two specimens are strengthened by adding drop panels or post-installed shear bolts. Punching shear failure is observed in the control specimen and the specimen with post-installed shear bolts after reaching their yield loads. However, even the control specimen without any strengthening exhibited considerable post-failure resistance and deformation capacity mainly due to sufficient integrity reinforcement, which had been installed in the bottom of the slab. Test results indicated that drop panels not only increase the flexural resistance but also raise the punching shear resistance of the connections significantly. Thus, no obvious punching shear failure is observed in the specimen with drop panels. However, post-installed shear bolts can only increase the punching shear resistance. For post-failure behaviour, this is not very effective. The test results demonstrated that flexural failure dominates the performance of test specimens, as relatively low slab reinforcement ratio but high span/thickness ratio was designed. [ABSTRACT FROM AUTHOR]

The interactions of loureirin A (LA) and cochinchinenin C (CC) with human serum albumin (HSA) under simulated physiological conditions (pH = 7.4) have been studied with fluorescence, UV–vis absorption spectroscopic method and molecular docking technique. The results indicated that there was a synergistic interaction between LA and CC, and the fluorescence quenching of HSA by LA (or CC) was a combined quenching procedure (dynamic and static quenching). At low compound concentrations, the quenching constants K SV of CC was larger than that of LA, which meant the CC efficacy may be better than that of LA. The negative △ H and △ S values suggested hydrogen bonds and van der Waals forces played the major role in the binding of LA (or CC) to HSA. The efficiency of energy transfer and distance between the compounds and HSA was calculated. Moreover, the results of synchronous and three-dimensional fluorescence demonstrated that the HSA microenvironment was changed in the presence of LA (or CC). Finally, the binding of LA (or CC) to HSA was modeled by molecular docking, which is in good accordance with the experimental studies. [ABSTRACT FROM AUTHOR]

In this paper, the shear behavior of glass fiber reinforced polymer (GFRP) bars reinforced ultra‐high‐performance concrete (UHPC) beams was investigated through experimental tests. Eight GFRP bars reinforced UHPC I‐beams were tested until shear failure with various stirrup ratio, reinforcement ratio, and shear span to depth ratio. The shear capacity, load–deflection relationship, cracking pattern, and failure mode were investigated in detail. The results show that the shear span to depth ratio has the greatest influence on the shear capacity of the beam among the three parameters, followed by the stirrup ratio and reinforcement ratio. The stirrup configuration can significantly improve the shear capacity and deformation resistance of the beam and can effectively reduce the stress concentration caused by the uneven distribution of steel fibers, which affects the failure mode of the beam. Increasing the stirrup ratio and reinforcement rate can improve the stiffness of the beam after cracking, and the larger the shear span to depth ratio is, the more significant the improvement effect is. Moreover, the stirrup enables the full development of the tensile capacity of GFRP bars. The existing equations of shear strength from five design codes and seven literatures are compared to the experimental results of 54 UHPC beams. It showed that the formula from the codes AFGC‐2013 and JSCE‐2006 codes is more accurate. The equations by Kwak, Jin, and Thiemicke's provide the best predictions. [ABSTRACT FROM AUTHOR]

Due to the use of deicing salt, marine and offshore environments may cause rebar corrosion in RC flat-slab floor systems. This increases the possibility of punching shear failure of slab–column connections. However, few research results are available for RC slab–column connections with corroded rebar under eccentric load, which is very common in realistic loading conditions. To fill this gap, 15 full-scale RC flat slab–column connections were fabricated and tested to investigate the performance of corroded slab–column connections under eccentric load. The design variables included reinforcement ratio, loading eccentricity, and degree of rebar corrosion. There were two stages of the experimental process, including (1) accelerated rebar corrosion tests; and (2) quasi-static tests. It was found from the test results that, in general, rebar corrosion had detrimental effects on the punching shear strength and stiffness of the connections. In addition, corrosion of reinforcement may change the failure mode of slab–column connections. However, it was unexpected that the energy-dissipating capacity and deformation capacity of slab–column connections with high reinforcement ratio and small loading eccentricity increased with increasing corrosion degree. [ABSTRACT FROM AUTHOR]

• Failure modes of RC beam-column sub-assemblages under progressive collapse were affected by loading regimes. • Load resisting mechanisms of RC sub-assemblages under different loading regimes were compared and discussed. • Structural resistance against progressive collapse was decomposed at different loading stages. • Analytical models were proposed and compared for assessing catenary action capacity of RC frames. The majority of previous quasi-static tests on disproportionate collapse simulated the column removal through applying concentrated load/displacement on the top of the removed column until failure. However, uniformly distributed service load always exists on the frames. Therefore, to reflect the actual load condition more accurately, uniformly distributed load should be applied along the beams first. Then, the temporary support is gradually removed to simulate the process of column removal. By this way, the beams may undergo only a small deflection as the dynamic effect is neglected. Thus, a subsequent concentrated loading process is employed to evaluate the behavior of the beams at the ultimate stage, which may be reached if the dynamic effect is considered. Such a loading process is named sequential loading regime. To evaluate the effects of loading regimes on the behavior of reinforced concrete (RC) frames under a middle column removal scenario, two series of half-scale RC beam-column sub-assemblages were tested in this study. It is found that the conventional concentrated loading regime could accurately estimate the yield strength and the compressive arch action capacity of the RC beam-column sub-assemblages, but it may over-estimate the catenary action (CA) capacity and the deformation capacity. Moreover, although the concentrated loading regime is convenient and able to demonstrate the load transfer mechanisms of the sub-assemblages against disproportionate collapse, it may mistakenly identify the locations of critical sections. Furthermore, based on the failure modes and local strain gauge results, analytical models were proposed for predicting the CA capacity of the tested specimens under two loading regimes. Results suggest that the analytical models could predict the CA capacity well. [ABSTRACT FROM AUTHOR]

The vulnerability of conventional RC structures to structural failure caused by the loss of corner columns has been emphasized over the past years. However, the lack of experimental tests has led to a gap in the knowledge for the design of RC building structures to mitigate the likelihood of progressive collapse caused by losing a ground corner column. Seven one-third scale RC beam-column substructures were tested to investigate their performance. The variables selected for the test specimens included beam transverse reinforcement ratios, type of design detailing (nonseismic or seismic), and beam span aspect ratios. Shear failure was observed to have occurred in the corner joint, and a plastic hinge was formed at the beam end near the fixed support in the nonseismic detailed specimens. However, plastic hinges were also formed in the beam end near to the corner joint for the seismically detailed specimen. Vierendeel action was identified as the major load redistribution mechanism before severe failure occurred in the corner joint, but a cantilever beam redistribution mechanism dominated after the corner joint suffered severe damage. The test results were compared with the Department of Defense design guidelines to highlight the deficiencies of the recently updated guidelines. [ABSTRACT FROM AUTHOR]

In this study, we proposed a simple and ultrasensitive approach called dynamic surface-enhanced Raman spectroscopy, which has been experimentally and theoretically demonstrated. The signal for rhodamine 6G is at least four orders of magnitude higher than that for the traditional method. A series of experiments have been exploited so as to verify the universality of our strategies. The results highlight a rapid and effective method in addictive narcotics residue apparatus, pesticide residue, crime scene or other public security field. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Experimental and analytical studies carried out on a RC moment-resisting frame after it is subjected to the loss of its ground-story exterior column is presented in this paper. Four full-scale interior beam-column subassemblages with varying degrees of nonseismic detailing were subjected to a monotonic loading regime to simulate the effects of redistributed gravity loads on the subassemblage after the loss of an exterior ground column. The variables in the test specimens include the beam longitudinal reinforcement ratios and the spacing of the transverse reinforcement within the beams, columns, and joints. The load-displacement relationships, crack development patterns, and failure mechanism obtained from the tests are also discussed. The finite-element models are validated by comparing the results with the experimentally obtained data. Parametric studies are then performed to study the influence factors, such as the beam transverse reinforcement ratio and the incorporation of an additional exterior beam-column element and slab on the global behavior of the subassemblages. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To develop a practical motor imagery-based brain-controlled switch as functional as a real-world switch that is reliable with a minimal false positive operation rate and convenient for users without the need of attention to the switch during a ‘No Control’ state (when not to activate the switch). Methods: Four healthy volunteers were instructed to perform an intended motor imagery task following an external sync signal in order to turn on a virtual switch provided on a computer screen. No specific mental task was required during the ‘No Control’ state. The beta band event-related frequency power (event-related desynchronization or ERD) from a single EEG Laplacian channel was monitored online in real-time. The computer continuously monitored the relative ERD power level until it exceeded a pre-set threshold and turned on the virtual switch. Results: Subject 1 achieved lowest average false positive rate of 0.4±0.9% in a five-session online study during the entire ‘No Control’ state, whereby the subject required 6.8±0.6 s of active urging time or total response time of 20.5±1.9 s to perform repeated attempts in order to turn on the switch in the online interactive switch operation. The average false positive rate among four subjects was 0.8±0.4% with average active urging time of 12.3±4.4 s or average response time of 36.9±13.0 s. Offline analysis from subject 2 shows that the overall performance from 10-fold cross-validation was 96.2% with 3 consecutive epoch averaging, which was further improved to 99.0% by computationally intensive methods. Conclusions: The novel design of the brain-controlled switch using the ERD feature associated with motor imagery achieved minimal false positive rate with a reasonable active urging time or response time to activate the switch. Significance: The reliability and convenience of the developed brain-controlled switch may extend current brain–computer interface capacities in practical communication and control applications. [Copyright &y& Elsevier]

Abstract: In this paper, two novel kinds of organic–inorganic monomer, SUA-APEMS and SUA-APS, have been achieved by modifying 5-sulfosalicylic acid (SUA) with 3-aminopropyl-methyl-diethoxylsilane (APEMS) and 3-aminopropyl trimethoxysilane (APS). These two organic–inorganic monomers were used as multi-functional bridged components, which can coordinate to metal ions (Tb3+/Eu3+/Zn2+) with carbonyl groups, strongly absorb ultraviolet and effectively transfer energy to metal ions through their triplet excited state, as well as involve in the sol–gel process with inorganic host precursor tetraethoxysilane (TEOS), resulting two series of molecular hybrid materials (named as SUA-APEMS/APS-RE) with double chemical bond (RE(Zn)–O coordination bond and Si–O covalent bond). The effective intra-molecular energy transfer process gives rise to the characteristic emission of metal ions and the chemical bond make the hybrid materials owning better properties. [Copyright &y& Elsevier]

Abstract: 4,5-Dihydroxy-1,3-benzenedisulfonic acid disodium salt (Tiferron, abbreviated as TF) is modified by 3-(triethoxysilyl)-propyl isocyanate (TESPIC) to afford a novel functional bridge intermediate (named as TFSi), which is used to coordinate with terbium or zinc ions and further introduced into silica matrices by Si–O bonds after hydrolysis and polycondensation processes. Subsequently, two luminescent chemically bonded organic–inorganic hybrid materials are assembled. Both of the two hybrids show the novel sphere-like microstructure except the Tb system that presents the smaller submicrometer sphere while Zn one shows the larger micrometer sphere, which may be ascribed to the different coordination behaviors of metal ions (Tb3+ or Zn2+). Green emission of Tb3+ hybrids and violet-blue luminescence of Zn2+ one have been achieved within the molecular-based hybrid materials. Besides, both Tb and Zn are introduced into the same hybrid systems through covalent Si–O bond, whose sphere particle size can be modified. Especially the photoluminescence can be enhanced, suggesting the intramolecular energy transfer that takes place between inert Zn2+ and Tb3+ within the chemically bonded hybrid systems. [Copyright &y& Elsevier]