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Objective: Survival and reconstruction in osteosarcoma is quite challenging. The study aimed to investigate the prognosis in patients treated with neoadjuvant chemotherapy and determine the clinical outcomes of expandable endoprosthesis reconstruction in children. Methods: From January 2009 to December 2014, we retrospectively analyzed 29 skeletally immature children (mean age, 10.5 years; range, 6–15 years) with osteosarcoma around the knee. Of the 29 patients who underwent neoadjuvant chemotherapy and limb salvage surgery, an expandable prosthesis was implanted for reconstruction. No patients were missed during follow‐up. The evaluation index involved follow‐up time, complication, functional results, and lengthening procedures. The survivorship and recurrence were assessed by GraphPad Software, and the function was evaluated by the Musculoskeletal Tumor Society (MSTS) scoring system. Results: A mean follow‐up time was 8.9 years (range, 6–12 years), and the overall 5‐year survival was 89.1% based on Kaplan–Meier analysis. Three patients suffered a relapse and one underwent amputation. Lung metastasis developed in one patient. At 6 months after the operation, patients had a mean MSTS score of 27 points (range, 24–29). Two patients underwent revision surgery, one for implant infection and one for aseptic loosening. Prognosis is correlated with alkaline phosphatase change after treatment. Conclusions: Chemotherapy scheme and limb salvage can achieve high survival rates. This expandable prosthesis was associated with good function and low complication rates. The character of expandability could be a method to overcome discrepancies in the growth period. [ABSTRACT FROM AUTHOR]

The actin cytoskeleton is a complex network of dynamic polymers, which plays an important role in various fundamental cellular processes, including maintenance of cell shape, polarity, cell division, cell migration, endocytosis, vesicular trafficking, and mechanosensation. Precise spatiotemporal assembly and disassembly of actin structures is regulated by the coordinated activity of about 100 highly conserved accessory proteins, which nucleate, elongate, cross-link, and sever actin filaments. Both in vivo studies in a wide range of organisms from yeast to metazoans and in vitro studies of purified proteins have helped shape the current understanding of actin dynamics and function. Molecular genetics, genome-wide functional analysis, sophisticated real-time imaging, and ultrastructural studies in concert with biochemical analysis have made yeast an attractive model to understand the actin cytoskeleton, its molecular dynamics, and physiological function. Studies of the yeast actin cytoskeleton have contributed substantially in defining the universal mechanism regulating actin assembly and disassembly in eukaryotes. Here, we review some of the important insights generated by the study of actin cytoskeleton in two important yeast models the budding yeast Saccharomyces cerevisiae and the fission yeast Schizosaccharomyces pombe. [ABSTRACT FROM AUTHOR]

Abstract: The electrolyte model LIQUAC has been used up till now to predict osmotic coefficients, mean ion activity coefficients, the vapor–liquid equilibrium (VLE) behavior, the solubility of gases in single and mixed solvent electrolyte systems, and solubilities of salts in aqueous solutions. In this paper, the required expressions for the calculation of salt solubilities not only in aqueous systems, but also in organic solvents and water–solvent electrolyte systems were deduced in detail based on the LIQUAC model with a fixed reference state and thermodynamic relations. Four salts (NaCl, KCl, NH4Cl and NaF) and two solvent (water and methanol) were selected to test the derived expressions. The results show that the LIQUAC model with a fixed reference state can be used to predict osmotic coefficients, solubilities of salts in aqueous solutions, vapor–liquid equilibria, and the solubilities of salts in water–organic solvent systems with strong electrolytes. [Copyright &y& Elsevier]

Abstract: Conventional methods to measure the hydraulic conductivity of an aquifer on a relatively large scale (10–100 m) require extraction of significant quantities of groundwater. This can be expensive, and otherwise problematic, when investigating a contaminated aquifer. In this study, innovative approaches that make use of tandem circulation wells to measure hydraulic conductivity are proposed. These approaches measure conductivity on a relatively large scale, but do not require extraction of groundwater. Two basic approaches for using circulation wells to measure hydraulic conductivity are presented; one approach is based upon the dipole-flow test method, while the other approach relies on a tracer test to measure the flow of water between two recirculating wells. The approaches are tested in a relatively homogeneous and isotropic artificial aquifer, where the conductivities measured by both approaches are compared to each other and to the previously measured hydraulic conductivity of the aquifer. It was shown that both approaches have the potential to accurately measure horizontal and vertical hydraulic conductivity for a relatively large subsurface volume without the need to pump groundwater to the surface. Future work is recommended to evaluate the ability of these tandem circulation wells to accurately measure hydraulic conductivity when anisotropy and heterogeneity are greater than in the artificial aquifer used for these studies. [Copyright &y& Elsevier]

A new rectangular concrete-filled hot-rolled-steel tubular flat column (RCSTFC) constructed from hot-rolled steel and internal steel plates was proposed in this study. The influence of the internal steel plate thickness (T I), angle steel thickness (T a), and cell number on the axial compression performance of RCSTFCs was investigated. The test results showed that RCSTFCs exhibit overall instability and local buckling under axial compression. Under D / B = 2.0, 2.67 and 3.0, the changes in T I , T a and cell number did not significantly influence the failure mode, strength index or axial deformation ductility of RCSTFCs with the same steel ratio. Furthermore, the area of the effectively confined zone and the stress-strain relationship of the confined concrete in the RCSTFCs were deduced, and a new calculation method for the axial load-carrying capacity of RCSTFCs was proposed. Compared to the design methods in GB 50936, CECS 159, AS 5100.6, and AISC 360, the proposed method produced relatively accurate results in the prediction of the axial load-carrying capacity of RCSTFCs. • RCSTFC configuration was studied by axial compression test. • Confined area and stress-strain relationship of concrete in RCSTFC were deduced. • New calculation method of RCSTFC axial load-carrying capacity was proposed. [ABSTRACT FROM AUTHOR]

AI-driven mineral prospectivity mapping (MPM) is a valid and increasingly accepted tool for delineating the targets of mineral exploration, but it suffers from noisy and unrepresentative input features. In this study, a set of fractal and multifractal methods, including box-counting calculation, concentration–area fractal modeling, and multifractal analyses, were employed to excavate the underlying nonlinear mineralization-related information from geological features. Based on these methods, multiple feature selection criteria, namely prediction–area plot, K-means clustering, information gain, chi-square, and the Pearson correlation coefficient, were jointly applied to rank the relative importance of ore-related features and their fractal representations, so as to choose the optimal input feature dataset readily used for training predictive AI models. The results indicate that fault density, the multifractal spectrum width (∆α) of the Yanshanian intrusions, information dimension (D1) of magnetic anomalies, correlation dimension (D2) of iron-oxide alteration, and the D2 of argillic alteration serve as the most effective predictor features representative of the corresponding ore-controlling elements. The comparative results of the model assessment suggest that all the AI models trained by the fractal datasets outperform their counterparts trained by raw datasets, demonstrating a significant improvement in the predictive capability of fractal-trained AI models in terms of both classification accuracy and predictive efficiency. A Shapley additive explanation was employed to trace the contributions of these features and to explain the modeling results, which imply that fractal representations provide more discriminative and definitive feature values that enhance the cognitive capability of AI models trained by these data, thereby improving their predictive performance, especially for those indirect predictor features that show subtle correlations with mineralization in the raw dataset. In addition, fractal-trained models can benefit practical mineral exploration by outputting low-risk exploration targets that achieve higher capturing efficiency and by providing new mineralization clues extracted from remote sensing data. This study demonstrates that the fractal representations of geological features filtered by multi-criteria feature selection can provide a feasible and promising means of improving the predictive capability of AI-driven MPM. [ABSTRACT FROM AUTHOR]

Background: Survival and reconstruction constitute important challenges in multimodal treatment of osteosarcoma of the proximal tibia. The purpose of this study was to assess the efficacy and prognosis of neoadjuvant chemotherapy and custom-designed endoprosthetic arthroplasty.Methods: A total of 69 patients with osteosarcoma of the proximal tibia were evaluated, including 43 males and 26 females, treated with multidisciplinary limb-salvage remedy from October 2003 to December 2013. They were at least 12 years old (mean, 20 years; range, 12-57 years). The gap between tumor and main artery/nerve was showed in MRI. Mean follow up was 69.5 months (range, 9-144 months). Kaplan-Meier survival curves were generated to assess prognosis and relapse rate. The initial symptoms and disease duration for each patient were recorded. Correlation analyses were performed for the association of various parameters with prognosis. Functional outcomes were evaluated using the Musculoskeletal Tumor Society (MSTS) guidelines after 6 months postoperatively, to analyze the relation between bone excision size and function recovery.Results: The resection lengths measured intraoperatively ranged from 80 to 230 mm, and contained 3 cm of normal bone around the tumor. A total of 3 courses of preoperative chemotherapy were administered to all cases. At final follow-up, 1 case showed recurrence. Meanwhile, 8 patients (11.6%) died from lung metastasis. Post-operative infection occurred in 3 patients; 1 case was maintained with revision surgery. Two cases underwent amputation. The mean MSTS system score was 21.6.Conclusions: The multidisciplinary treatment result in an overall positive outcome, with improved function. [ABSTRACT FROM AUTHOR]

The development of mineral prospectivity mapping (MPM), which aims to outline and prioritize mineral exploration targets, has been spurred by advances in data-driven machine learning algorithms. Supervised data-driven MPM is a typical few-shot task, suffering from a scarcity of labeled data, the over-fitting of models and an uncertainty of predictions. The main objective of this contribution is to propose a robust framework of few-shot learning (FSL), combining data augmentation and transfer learning to enable the generation of prospectivity models with excellent predictive efficiency and low uncertainty. The mineral systems approach was used to transfer a conceptual mineral system into mappable exploration criteria. Synthetic minority over-sampling technique (SMOTE) was employed to augment and balance the labeled dataset, allowing for model pre-training with the large synthetic training dataset of a source domain. The knowledge derived from pre-trained models was then transferred to the target domain by fine-tuning, and the prospectivity model was generated in light of over-fitting and uncertainty assessments. The proposed FSL framework was applied to tungsten prospectivity mapping in southern Jiangxi Province. The results indicated that the SMOTE-ed balanced dataset boosted the classification accuracy in the training process. The FSL models yielded an arch-shaped prediction point pattern which was favorable for focusing potential targets with high probability and low uncertainty. The FSL models achieved a high predictive performance (test AUC = 0.9172) and the lowest quantitative over-fitting value compared to the models derived from the benchmark algorithms of random forest and support vector machine. Four levels of potential targeting zones, considering both predictive efficiency and uncertainty, were extracted from the resulting FSL prospectivity map. The final high-potential and low-risk exploration targets only cover 4.27% of the area, but capture 41.53% of known tungsten deposits, thus achieving a superior predictive performance. This study highlights the capability of FSL framework to control over-fitting and generate high-confidence exploration targets with low levels of uncertainty. [ABSTRACT FROM AUTHOR]

An approach combining U-shaped dampers (USDs) and rocking walls is proposed in this paper to improve the seismic performance of traditional precast reinforced concrete (RC) frames with cladding panels (PRCFCPs): (1) the steel bar and USD connection methods are adopted at the top and bottom of the cladding panels to use the relative deformation between the cladding panels and the main structure and then dissipate the seismic energy and (2) rocking walls are added to the structure to control the structural deformation profiles. The USD numerical model is calibrated using the test data, and a series of nonlinear pushover analyses, dynamic time-history analyses, and incremental dynamic analyses are successively performed to compare the seismic performance and collapse capacity of the PRCFCP, PRCFCP with USDs (PRCFCP-USD), and PRCFCP with USDs and rocking walls (PRCFCP-USD-RW).The results show that the USDs in the PRCFCP-USD-RW undergo more uniform deformation along the structural height and higher energy dissipation efficiency and the PRCFCP-USD-RW exhibits enhanced seismic performance and collapse capacity, which verify the superiority of the proposed combined approach. [ABSTRACT FROM AUTHOR]

• Flexural performance of CWFBs with CHCSs was verified by out-of-plane flexural tests. • The CWFBs with CHCSs had shear lag effects in both the tension and compression zones. • The effect of loading method and slab width on CWFB effective width was analyzed. • The equation to calculate the effective width of the CWFB was deduced theoretically. To investigate the flexural performance and effective flange width of composite wide flat beams (CWFBs) with composite hollow core slabs (CHCSs), four CWFB specimens with double-sided CHCSs were tested and analyzed. The test results indicated that all specimens showed typical flexural damage. The CWFB with CHCSs had shear lag effect in both tension and compression zones. Increasing the width of the CHCSs resulted in a greater effective width, stiffness, and load carrying capacity of CWFB with CHCSs. Compared with the three-point loading method, the effective width of CWFB with CHCSs was larger for the four-point loading method and the uniform loading method. In addition, finite element models (FEMs) of the tested specimens in MSC. Marc software were validated by the test results, and 30 FEMs were further analyzed. Finally, the equations for calculating the effective width were obtained for the CWFB with CHCSs under uniform, four-point and three-point loads. [ABSTRACT FROM AUTHOR]

Orthopedic implants, using materials such as titanium, are extensively used in clinical surgeries. Despite its popularity, titanium is still inadequate to reliable osseointegration due to aseptic loosing. Fibrous encapsulation on the titanium implant interface prevents osseointegration and leads to the loosing of orthopedic implant. In this study, decorin was loaded on titanium surface by polydopamine film to examine fibrous encapsulation inhibition and bone growth acceleration. The coating of decorin was evaluated by X-ray photoelectron spectroscopy (XPS) and fluorescence microscopy. Quantitative analysis showed increased decorin coating on titanium surface when decorin in the loading solution increases. To test the effect of decorin modification, fibroblast and osteoblast cultures were utilized in vitro . The results showed that the functions of fibroblasts (proliferation, migration and collagen synthesis) were significantly attenuated on the decorin-modified surfaces and this anti-fibrous effect could be due to fibrotic gene suppression by decorin. In contrast, osteoblastic activities, such as calcium deposition and alkaline phosphatase (ALP) activity, were enhanced by the modified decorin. These results suggest that decorin coating on titanium surface inhibited proliferation and function of fibroblasts and improved that of osteoblasts. Therefore, this study is potentially useful for enhancing orthopedic implant. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tenogenic patch can promote the tendon-like morphology, adhesion, proliferation and migration of tendon fibroblasts in vitro. • The tenogenic patch enhanced the collagen fiber regeneration in the acute rotator cuff tear model. • The patch scaffold can strengthen tendon and the regeneration of tendon-to-bone insertion. Rotator cuff tear of shoulder is a common tendon injury. Current therapeutic strategies are unsatisfactory because of poor biomechanical properties of the repaired rotator cuff tendons. To solve this problem, a newly biofabricated tenogenic patch by uniaxial cold-drawing technology was applied for the treatment of acute rotator cuff tear and its therapeutic effects were evaluated in vitro and in vivo. The cytocompatibility results indicated that the engineered patch was capable of promoting the spreading, migration and proliferation of tendon fibroblasts in vitro. Stress–strain curves of the sutured patch indicated improved elasticity followed by the yield phenomena, nonlinear plasticity and obviously delaminated rupture. The tenogenic patch also showed significantly enhanced collagen I deposition and better tendon-to-bone healing in the rat rotator cuff tear models in vivo. Furthermore, implantation with the tenogenic patch also promoted the fibrocartilage formation in Safranin-O/Fast green-staining. The analysis of biomechanical properties showed that the tenogenic patch is capable of improving the ultimate load of the repaired tendon. Therefore, the tenogenic patch may constitute an efficient strategy to enhance tendon-to-bone healing for clinical repair applications of rotator cuff tear. [ABSTRACT FROM AUTHOR]

• This study proposed a SC-CRWBB by introduced BRBs at corner and UPTs at center to CRW. • The seismic performance of SC-CRWBB was studied through the quasi-static tests. • The influence of UPTs initial stress and BRB area on residual drift was analyzed. • The hysteretic curve and the required UPTs initial stress were theoretically deduced. A new self-centering controlled rocking wall (CRW) with buckling-restrained braces (BRBs) at the base (SC-CRWBB) is proposed to improve the energy dissipation and self-centering capacities of CRWs. The SC-CRWBB was established by adding unbonded posttensioned tendons (UPTs) at the center and BRBs at two corners of a CRW. The quasi-static test results demonstrated that the proposed SC-CRWBB achieved a satisfactory seismic performance. Structural damage was concentrated in the BRBs, while a few cracks occurred in the surface between the CRW and mortar layer and between the BRBs and CRW. Then, a finite element model (FEM) of the test specimen was created in ABAQUS software to study the influence of the initial stress of the UPTs and sectional area of the BRB core plate on the residual deformation and lateral carrying capacity of the SC-CRWBB. Finally, an analytical method for the investigation of SC-CRWBBs was validated against the test and FE analysis results. [ABSTRACT FROM AUTHOR]

Dengue hemorrhagic fever (DHF)/Dengue shock syndrome (DSS) is a fatal infectious disease that demands an effective treatment. Interferon (IFN)-stimulated genes (ISGs) induced by dengue virus (DENV) exert antiviral effects. Among ISGs, IFN-α inducible gene 6 (IFI6) was increased in DENV infected human umbilical vascular endothelial cells (HUVECs) by microarray analysis in our previous study. However, its function is incompletely understood. In this study, we confirmed that IFI6 was markedly induced in DENV infection of both primary HUVECs and EA.hy926 cell lines. Recombinant EA.hy926 cell lines in which IFI6 was either over-expressed (IFI6+/+) or knocked-down (IFI6-/-) were generated. The activation of caspase-3 and intrinsic apoptosis-related protein caspase-9 were down-regulated in IFI6+/+ but up-regulated in IFI6-/- cells at 24–48 hrs post-infection. After incubation with DENV for 48 hrs, the mitochondrial membrane potential (Δψ(m)) was more stable in IFI6+/+ cells but reduced in IFI6-/- cells, as assayed by fluorescence staining with JC-1. We observed that Bcl-2 expression was increased in IFI6+/+ and decreased in IFI6-/- cells. By contrast, Bax expression was decreased in IFI6+/+ and increased in IFI6-/- cells. It is presumed that the anti-apoptotic function of IFI6 is expressed by regulating the rheostatic balance between bcl-2/bax expression and inhibition of Δψ(m) depolarization during DENV infection of vascular endothelial cells(VECs). In addition, the pro-apoptotic protein X-linked Inhibitor of Apoptosis (XIAP)-Associated Factor 1(XAF1) expression had been reported to be up-regulated and led to the induction of apoptosis in DENV2-infected VECs,but the relationship between XAF1 and IFI6 dengue virus-induced apoptosis in VECs warrants further study. [ABSTRACT FROM AUTHOR]

Abstract: Acellular porcine cornea stroma (APCS) prepared using pancreatic phospholipase A2 was proven to be promising corneal scaffold. However, its dense ultrastructure provides insufficient space that prevents the seeded cells from organizing into a functional tissue. In this report, freezing dry APCS (FD-APCS) biomaterials containing pores with different sizes were fabricated at different pre-freezing temperatures of −10, −80 or −198°C, and the percentage of large pores (equivalent circle diameter≥10μm) was 93.55%, 69.36%, 35.79%, while the small pores (<10μm) were account for 6.45%, 30.64%, 64.21%, respectively. Both porosity and specific surface area increased in FD-APCS fabricated with decreased pre-freezing temperature, and they were dramatically higher than those in APCS. The three FD-APCS groups displayed higher permeability than APCS, and the −10°C FD-APCS possessed the highest permeability. The keratocytes seeded in the FD-APCS construct survived well in vitro, and maximal cell proliferation was observed in the −10°C FD-APCS. The light transmittance of the FD-APCS-transplanted cornea after interlamellar keratoplasty in rabbit eyes displayed no significant difference from the APCS-transplanted or native cornea. This study indicated that the porous FD-APCS prepared using pancreatic phospholipase A2 is capable of serving as potential scaffold for constructing tissue-engineered cornea with biological properties. [Copyright &y& Elsevier]

Abstract: The ability to quantify the mass flux of a groundwater contaminant that is leaching from a source area is critical to enable us to: (1) evaluate the risk posed by the contamination source and prioritize cleanup, (2) evaluate the effectiveness of source remediation technologies or natural attenuation processes, and (3) quantify a source term for use in models that may be applied to predict maximum contaminant concentrations in downstream wells. Recently, a number of new methods have been developed and subsequently applied to measure contaminant mass flux in groundwater in the field. However, none of these methods has been validated at larger than the laboratory-scale through a comparison of measured mass flux and a known flux that has been introduced into flowing groundwater. A couple of innovative flux measurement methods, the tandem circulation well (TCW) and modified integral pumping test (MIPT) methods, have recently been proposed. The TCW method can measure mass flux integrated over a large subsurface volume without extracting water. The TCW method may be implemented using two different techniques. One technique, the multi-dipole technique, is relatively simple and inexpensive, only requiring measurement of heads, while the second technique requires conducting a tracer test. The MIPT method is an easily implemented method of obtaining volume-integrated flux measurements. In the current study, flux measurements obtained using these two methods are compared with known mass fluxes in a three-dimensional, artificial aquifer. Experiments in the artificial aquifer show that the TCW multi-dipole and tracer test techniques accurately estimated flux, within 2% and 16%, respectively; although the good results obtained using the multi-dipole technique may be fortuitous. The MIPT method was not as accurate as the TCW method, underestimating flux by as much as 70%. MIPT method inaccuracies may be due to the fact that the method assumptions (two-dimensional steady groundwater flow to fully-screened wells) were not well-approximated. While fluxes measured using the MIPT method were consistently underestimated, the method''s simplicity and applicability to the field may compensate for the inaccuracies that were observed in this artificial aquifer test. [Copyright &y& Elsevier]

• A new type of superimposed reinforced concrete shear wall with insulation is proposed by integrating the insulation panel into the precast exterior concrete panel to achieve both bearing and insulation capabilities. • The connection method of the longitudinal reinforcement at the horizontal joints of the superimposed reinforced concrete shear wall is indirect splicing on one side and direct splicing on the other side, and the direct splicing area is moved upwards to avoid the horizontal joints. A new type of superimposed reinforced concrete shear wall with insulation (SRCSWI) is proposed in this paper by integrating the insulation panel into the precast exterior concrete panel to achieve both bearing and insulation capabilities. Four full-sized specimens, including one cast-in-place reinforced concrete shear wall (CRCSW), two SRCSWIs and one superimposed reinforced concrete shear wall (SRCSW) without insulation, were designed for use in pseudo-static tests. The test results showed that the failure modes of the SRCSWIs were similar to those of the CRCSW and SRCSW. For the SRCSWI with a lower reinforcement ratio for the boundary elements, fewer cracks occurred in the wall, while the opening width of the cracks in the horizontal joints was relatively large, which means that the plastic deformation of this specimen was concentrated near the horizontal joints. For the SRCSWIs, the precast exterior concrete panel contributed little to the stiffness and carrying capacity of the walls. For the SRCSWI specimens, SRCSW specimen and CRCSW specimen with the same design axial load ratio, the stiffness, ductility and carrying capacity were basically consistent. For the SRCSWI specimen with a lower axial force, the carrying capacity was lower, but the ductility ratio and energy dissipation coefficient were higher than those of the other specimens. Finally, solid finite element (FE) models of the test specimens were established in ABAQUS and validated with the experimental results. The distribution of concrete damage, steel reinforcement stress distribution and hysteretic curves in the numerical analysis were basically consistent with the test results. [ABSTRACT FROM AUTHOR]