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Non-Gaussian dynamic processes are ubiquitous due to the presence of non-Gaussian distributed variables. Therefore, fault detection of non-Gaussian dynamic processes plays a vital role to maintain the safe operation of systems and symmetry of data distribution. In this paper, a dynamic generalized likelihood ratio (DGLR)-based fault detection method is proposed for non-Gaussian dynamic processes. Different from the conventional principal component analysis (PCA)-based, dynamic PCA-based, and PCA-based GLR fault detection methods, the novelty of the proposed method is that the GLR is extended to non-Gaussian dynamic processes, and the randomized algorithm is integrated for threshold setting to attenuate the influence of non-Gaussian. The application scope of these methods is also discussed. The proposed method is compared with four existing fault detection methods on a numerical simulation and the continuous stirred-tank reactor (CSTR) process. The achieved results show that the proposed method is able to significantly improve the detection performance in terms of fault detection rate and prompt response to faults. [ABSTRACT FROM AUTHOR]

Learning partial differential equations (LPDEs) from training data for particular tasks has been successfully applied to many image processing problems. In this paper, we propose a more effective LPDEs model for vector-valued image tasks. The PDEs are also formulated as a linear combination of fundamental differential invariants, but have several distinctions. First, we simplify the current LPDEs system by omitting a PDE which works as an indicate function in current ones. Second, instead of using L2-norm, we use the L1-norm to regularize the coefficients with respect to the fundamental differential invariants. Third, as the objective function is not smooth, we resort to the alternating direction method to optimize it. We illustrate the properties of our LPDEs system by several examples in denoising and demosaicking of RGB color images. The experiments demonstrate the advantage of the proposed method over other PDE-based methods. [ABSTRACT FROM AUTHOR]

Recent years have seen exciting breakthroughs in biomedical sciences that are producing truly novel therapeutics for unmet patient needs. However, the pharmaceutical industry is also facing significant barriers in the form of pricing and reimbursement, continued patent expirations and challenging market dynamics. In this article, we have analyzed data from the 1995–2015 period, on key aspects such as revenue distribution, research units, portfolio mix and emerging markets to identify four key trends that help to understand the change in strategic focus, realignment of R&D footprint, the shift from primary care toward specialty drugs and biologics and the growth of emerging markets as major revenue drivers for big pharma. [ABSTRACT FROM AUTHOR]

Abstract: Cationic lipid-coated magnetic nanoparticles (MPs) associated with transferrin were evaluated as gene transfer vectors in the presence of a static magnetic field. MPs were prepared by chemical precipitation and were surface-coated with cationic lipids, composed of DDAB/soy PC (60:40mole/mole). These cationic MPs were then combined with polyethylenimine (PEI) condensed plasmid DNA, followed by transferrin. The resulting magnetic electrostatic complexes retained relatively compact particle size and showed complete DNA condensation. Their transfection activity in the presence of a static magnetic field was evaluated by luciferase and green fluorescent protein (GFP) reporter genes. The magnetic complexes exhibited up to 300-fold higher transfection activity compared to commonly used cationic liposomes or cationic polymer complexes, based on luciferase assay. The enhancement in transfection activity was maximized when the cells were exposed to the vectors for a relatively short period of time (15min), or were treated in media containing 10% serum. Incorporation of transferrin further improved transfection efficiency of the cationic MPs. However, when cells were incubated for 4h in serum-free media, magnetic and non-magnetic vectors showed similar transfection efficiencies. In conclusion, transferrin-associated cationic MPs are excellent gene transfer vectors that can mediate very rapid and efficient gene transfer in vitro in the presence of a magnetic field. [Copyright &y& Elsevier]

Abstract: A novel method for synthesis of anti-EGFR immunoliposomes using folate–folate binding protein (FBP) affinity is described. An anti-EGFR antibody (cetuximab or C225) was covalently linked to FBP via a thioether bond. Liposomes incorporating a lipophilic folate derivative (folate-PEG-cholesterol) were prepared by polycarbonate membrane extrusion. Anti-EGFR immunoliposomes were then obtained by combining FBP-C225 and folate-liposomes and evaluated for uptake and cytotoxicity in EGFR-overexpressing U87 human glioblastoma cells. Anti-EGFR immunoliposomes constructed via folate–FBP affinity exhibited excellent stability under physiological pH, and quickly released the bound FBP-C225 upon low pH (pH 3.5) treatment. Flow cytometry and fluorescence microscopy showed similar receptor-specific binding and internalization for both folate–FBP affinity-coupled and covalently coupled C225-immunoliposomes, but not for the non-targeted IgG-immunoliposomes. C225-immunoliposomes loaded with anticancer drug doxorubicin were more cytotoxic than non-targeted immunoliposomes in EGFR-overexpressing U87 glioma cells. Folate–FBP affinity is a potential method for construction of immunoliposomes and may have applications in synthesis of targeted drug carriers in general. [Copyright &y& Elsevier]

The semi-Z-source inverter (SZSI) with least switch count (only two switches) eliminates the leakage current due to the doubly grounded structure. However, the main disadvantage is the high voltage stresses of the switches (the sum of double photovoltaic output voltages and the grid voltage amplitude). This article proposed an improved inverter based on the SZSI. It inherits the advantage of less leakage current and owns another merit of lower switch voltage stress. Besides, the operation principle of the proposed inverter is bimodal and only two switches operate at high frequency in each mode. First, the circuit structure and the operation principle are introduced in detail. Then, the grid current controllers in both modes are designed. Two comparisons are investigated for better clarification of the pros and cons of the proposed inverter. Finally, experimental results, obtained with a 500-W laboratory prototype, are presented to validate its performance. [ABSTRACT FROM AUTHOR]

Traditional power factor correction (PFC) converters usually employ a large electrolytic capacitor to ensure a stiff output voltage. However, the electrolytic capacitor is not expected in terms of the reliability and the size of the system. This article proposes a peak and valley current control for Cuk PFC converter to remove the bulky electrolytic capacitor. The proposed control is realized by a combination of analog and digital circuits. The analog circuits are used to accomplish the real-time comparison between the actual currents and their reference values. And the digital circuits are employed to deal with simple logical judgement. Different from the existing full digital control technique, which needs a high-quality digital signal processor (DSP) to process complex arithmetic operation, the proposed control concept even can only require a low performance microcontroller unit. Besides, the control delay is avoided. This article first analyzes the operation stages of the Cuk PFC converter. Then, design considerations of main circuit and control circuit are introduced. Finally, the experimental results from 200W Cuk PFC converter are presented to verify the effectiveness of the proposed control. [ABSTRACT FROM AUTHOR]

Abstract: In order to develop an integrated kinetic model of dynamic recrystallization (DRX), hot compression tests were performed in X70 pipeline steel over a temperature range of 1173–1473K and strain rate range of 0.05–15s−1 on a Gleeeble-3500 thermomechanical simulator. The stress–strain data was well smoothed and investigated. The onset of DRX was detected from the inflection point on the curve of strain hardening rate versus flow stress which can be well described by a third order equation. The activation energy of DRX and Zener–Hollomon (Z) parameter were determined by regression analysis of experimental stress–strain data. An approach based on the relationship between dislocation density and stress was used to quantify the fraction of DRX and in this case, a revised Avrami equation was developed. The good agreement between prediction value and experimental results proved the verification of the kinetics model of DRX. [Copyright &y& Elsevier]

Abstract: The main purpose of this work is to develop a pragmatic model to predict isothermal austenite grain growth in a hot rolled dual phase steel. Austenite grain growth kinetics have been studied in different heating conditions, involving soaking time and soaking temperature as well as heating rate. The contribution of the initial grain size to the time exponent in Beck equation was analyzed mathematically. The time exponent and initial grain size were also quantitatively described by models proposed. It was found that the time exponent value which had a wide range increased when the temperature decreased. No meaningful activation energy can be obtained for the grain growth process when the time exponent varies. The initial grain size increases with the soaking temperature. The model predictions present a good agreement with experimental austenite grain growth data. [Copyright &y& Elsevier]

Abstract: This study was designed to investigate the biomechanical effects of rapid maxillary expansion (RME) in the patient with unilateral cleft lip and palate (UCLP). A finite element model of a patient''s craniofacial complex with UCLP was created using data from spiral computed tomographic (CT) scanning. A transversal displacement with a magnitude of 5mm was applied on the maxillary premolar and first permanent molar crown of the model simulating the clinical situation. The stress and deformation within the craniofacial complex were then calculated and analyzed during 0.25- and 5-mm expansions. The corresponding orthodontic forces on each loaded tooth were also calculated. Obtained results revealed the biomechanical performance of the craniofacial complex with UCLP undergoing RME, including the distribution pattern of the stress and displacement, the transmission and dissipation of the orthodontic force, the stress level and the magnitude of the orthodontic force. All these findings could help us better comprehend the biomechanical mechanism of RME in the UCLP patient and provided theoretic data for optimizing surgical assisted RME in clinic. [Copyright &y& Elsevier]

Hair follicle stem cells are pluripotent and have a self-renewal capacity and multi-differentiation potential in vitro. As hair follicle stem cells can be easily sampled from the skin and hair of clinical patients at a considerable quantity, these cells have potential applications in wound repair and skin tissue engineering. Effective approaches for the in vitro culture and amplification of mouse hair follicle stem cells, as well as the in vitro osteogenic differentiation potential and cell source when obtaining mouse-separated cells were examined. Serial subculture was performed in different culture systems. Cell source was detected based on the relevant surface markers derived from mouse hair follicles at the gene and protein levels, and the differential potential was determined. The proliferative ability of hair follicle-derived stem cells obtained from mouse embryonic fibroblast (MEF)/keratinocyte serum-free medium (KSF)-conditioned medium was the highest among all culture systems. The induced group had a stronger osteogenic differentiation potential compared with the non-induced group, indicating that the cells obtained from MEF/KSF-conditioned medium were cells derived from the hair follicle dermal papilla. Therefore, the strong osteogenic differentiation potential of the hair follicle-derived mesenchymal stem cells was screened with MEF/KSF-conditioned culture medium following amplification, and biological characteristics similar to those of hair follicle dermal papilla cells were observed. [ABSTRACT FROM AUTHOR]