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Liwen Kuang,1,* Chenchen Zhang,1,* Binghui Li,1 Haibo Deng,1 Ran Chen,1 Gongchi Li2 1Department of Wound Repair Surgery, Liyuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430062, People’s Republic of China; 2Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, People’s Republic of China*These authors contributed equally to this workCorrespondence: Gongchi Li, Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, No. 1277 Jiefang Road, Wuhan, Hubei, 430022, People’s Republic of China, Tel +8613618615209, Email ligongchi@foxmail.comPurpose: Diabetic wound is a highly prevalent and refractory disease. Extensive studies have confirmed that keratinocytes and macrophages play an important role in the process of wound healing. Additionally, exosomes are regarded as a vital intercellular communication tool. This study aimed to investigate the role of human keratinocyte-derived exosomal MALAT1 in the treatment of diabetic wound by influencing the biological function of macrophages.Methods: We mainly assessed the function of MALAT1 on the biological changes of macrophages, and the expression of MALAT1 in the keratinocyte-exosomes analyzed by quantitative real-time polymerase chain reaction (RT-qPCR). The downstream interaction between RNAs or proteins was assessed by mechanistic experiments. Besides, we evaluated the effects of human keratinocyte-derived exosomal MALAT1 on diabetic wound healing in vivo to verify in vitro results.Results: We demonstrated that human keratinocyte-derived exosomal MALAT1 enhanced the biological functions of high glucose-injured macrophages, including phagocytosis, converting to a pro-healing phenotype and reducing apoptosis. Mechanistically, MALAT1 accelerated the expression of MFGE8 by competitively binding to miR-1914-3p, thereby affecting the function of macrophages and the signal axis of TGFB1/SMAD3, and finally promoting the healing of diabetic wounds. Human keratinocyte-derived exosomal MALAT1 might promote collagen deposition, ECM remodeling, and expression of MFGE8, VEGF, and CD31 but reduce the expression of TGFB and SMAD3 in an in vivo model of diabetic mice wounds, which accelerated diabetic wound healing and restored its function.Conclusion: The current study revealed that human keratinocyte-derived exosomal MALAT1 would suppress miR-1914-3p to activate MFGE8 and eventually promote wound healing by enhancing macrophage phagocytosis, converting to a pro-healing phenotype and reducing apoptosis. It proposed that keratinocyte-derived exosomes might have the capacity to serve as a new method for the clinical treatment of diabetic wound.Graphical Abstract: Keywords: exosomes, keratinocytes, macrophages, MALAT1, diabetic wound healing

With the progress of deep learning, object detection has attracted great attention in computer vision community. For object detection task, one key challenge is that object scale usually varies in a large range, which may make the existing detectors fail in real applications. To address this problem, we propose a novel end-to-end Attention Feature Pyramid Transformer Network framework to learn the object detectors with multi-scale feature maps via a transformer encoder-decoder fashion. AFPN learns to aggregate pyramid feature maps with attention mechanisms. Specifically, transformer-based attention blocks are used to scan through each spatial location of feature maps in the same pyramid layers and update it by aggregating information from deep to shadow layers. Furthermore, inter-level feature aggregation and intra-level information attention are repeated to encode multi-scale and self-attention feature representation. The extensive experiments on challenging MS COCO object detection dataset demonstrate that the proposed AFPN outperforms its baseline methods, i.e., DETR and Faster R-CNN methods, and achieves the state-of-the-art results.

The modification of wool fabrics is significant in preparation of functional textiles. Sodium periodate oxidized β-cyclodextrin was grafted onto wool fabric through Schiff base reaction to obtain fabric with controlled release property. β-cyclodextrin was oxidized to aldehyde-β-cyclodextrin, and the results show that the inclusion constant and aldehyde content of aldehyde-β-cyclodextrin are varied with the reaction parameters such as molar ratio of reaction agents and the reaction temperature. The degree of oxidation was confirmed by ion chromatography. The drug loading test shows that the oxidized cyclodextrin still had inclusion ability towards phenolphthalein, while the inclusion constant was only 50 % of the original β-CD. The ATR-FTIR spectra proved the occurrence of grafting reaction between the aldehyde groups of aldehyde-β-cyclodextrin and the amino groups on wool fiber. The aldehyde-β-cyclodextrin grafted wool fabric show great washing durability even after 5 washing cycles. Compared with the aldehyde-β-cyclodextrin power, the inclusion ability of aldehyde-β-cyclodextrin fixed on the wool fiber decreased by 60 %.

To explore the extensive oxidative mechanism of syringaldehyde, vanillin, and p-hydroxybenzaldehyde during the alkaline wet oxidation process (AWOP), the yield of these aromatic aldehydes from AWOP at various temperatures and reaction times was studied. The results showed that the aromatic aldehydes could not be converted into the corresponding aromatic acids during the AWOP, and that the aromatic aldehyde was stable when subjected to the oxygen-free AWOP. However, as the reaction temperature increased or the number of methoxyl groups on the aromatic ring increased, the yield of aromatic aldehyde sharply decreased during the AWOP. The reason for the decreased yield was that the aromatic aldehyde underwent ring-opening reactions. The possible mechanism of the degradation indicated that the number of methoxyl groups on the phenolic ring determined the stability of the key intermediate of this reaction. The conversion of isoeugenol to vanillin during the AWOP at 60 ºC was > 99%, and the vanillin yield and selectivity were both 69.8%, indicating that the decrease in yield of the product from this degradation of lignin substrate and the product can be reduced or avoided in the AWOP at suitable temperature.

β-cyclodextrin (β-CD) was oxidized by sodium periodate to yield a mixture of dialdehyde oligosaccharides. The periodate-oxidized β-CD (O-β-CD) together with chitosan (CTS) was firstly used to finish poly(ethylene terephthalate) (PET) fabrics by immersion-padding method, in which O-β-CD acted as a hydrophilic finishing agent plus a cross-linker. The processes including the periodate oxidization of β-CD and the CTS/O-β-CD hydrophilic finishing of PET fabrics were eco-friendly. The results from the hydroxylamine hydrochloride titration showed that the aldehyde content in O-β-CD was 3.0 mmol/g. With increasing the CTS/O-β-CD mass ratio, the finished fabric had better hydrophilic properties. When the CTS/O-β-CD mass ratio was 1:1, the moisture regain and water drops wetting time of the finished fabric reached 1.85 % and 5.06 s, respectively. They became 1.50 % and 5.70 s, respectively after 25 times of laundering cycle. The occurrence of cross-linking between O-β-CD and CTS was confirmed by the gel test and FT-IR characterization. The cross-linking network deposited on the fiber surface brought on excellent wash resistance of the CTS/O-β-CD finished PET fabrics.

High adsorption efficiency, active to both anionic and cationic dyes and simple desorption are three main challenges of the existed adsorbents for decolorization of the dye-contained wastewaters. Porous foams based on L-lysine (Lys) molecular-grafted cellulose were firstly designed and fabricated to overcome those challenges. Cellulose were grafted with Lys in 1-butyl-3-methylimidazolium chloride (BMIMCl) via a chemical connection resulted from glycidyl methacrylate (GMA). The synthesized cellulose derivative (Cell-g-PGMA-Lys) was regenerated in the morphology of foam by non-solvent induced phase inversion from the BMIMCl-based solutions. The presence of Lys moieties and porous structure of Cell-g-PGMA-Lys were confirmed with a series of instrumental analysis. Both anionic reactive brilliant red X-3B (RBR X-3B) and cationic methylene blue (MB) were effectively adsorbed on and desorbed from Cell-g-PGMA-Lys by adjusting the solution pH value. Cell-g-PGMA-Lys had higher adsorption capacities than most of the reported adsorbents and was easy to separate from the decolorized water. It could be reused many times with little reduction of the adsorption capacity, which remained 86.9% and 92.5% for RBR X-3B and MB respectively after six adsorption-desorption cycles. The isothermal and kinetic adsorption proved that dyes were adsorbed single-layered on Cell-g-PGMA-Lys depending upon the electrostatic interaction between adsorbent and adsorbate.

Text classification is an important task in natural language processing. In the past few years, some prominent methods have achieved great results in text classification, but there is still a lot of room for development in enhancing the expressive capabilities of text features. In addition, although deeper networks can better extract features, they are easy to produce gradient disappearance or gradient explosion problems. To solve these problems, this paper proposed a hybrid model based on cross-layer connected gated recurrent unit capsule network (CBiGRU_CapsNet). Firstly, the model fused word vectors trained by Word2Vec and GloVe to form the network input layer. In the stage of high-level semantic modeling of text, a cross-layer connected gated recurrent unit has been proposed, which can solve the problem of gradient disappearance or explosion, and strengthen the transfer between features of each layer. Furthermore, capsule network is applied to obtain the rich spatial position information in the deep high-level semantic representation, and the weight value of important features has been increasing through the core dynamic routing algorithm of the capsule network to improve the expression ability of the features, which is then inputted to the softmax layer to complete text classification task. The experimental results on several public datasets shown that CBiGRU_CapsNet outperforms the state-of-the-art models in terms of the accuracy for text classification tasks.

IntroductionVenous thromboembolism (VTE) occurs in up to 40%–80% of patients after hip and knee arthroplasty. Clinical decision-making aided by guidelines is the most effective strategy to reduce the burden of VTE. However, the quality of guidelines is dependent on the strength of their evidence base. The objective of this article is to critically evaluate the quality of VTE prevention guidelines and the strength of their recommendations in VTE prophylaxis in patients undergoing hip and knee arthroplasty.MethodsRelevant literature up to 16 March 2020 was systematically searched. We searched databases such as Web of Science, PubMed, EMBASE, Cumulative Index of Nursing and Allied Health Literature, China National Knowledge Infrastructure and WanFang and nine guidelines repositories. The identified guidelines were appraised by two reviewers using the Appraisal of Guidelines for Research and Evaluation II and appraised the strength of their recommendations independently. Following quality assessment, a predesigned data collection form was used to extract the characteristics of the included guideline.ResultsWe finally included 15 guidelines. Ten of the included guidelines were rated as ‘recommended’ or ‘recommended with modifications’. The standardised scores were relatively high in the domains of Clarity of Presentation, and Scope and Purpose. The lowest average standardised scores were observed in the domains of Applicability and Stakeholder Involvement. In reference to the domains of Rigour of Development and Editorial Independence, the standardised scores varied greatly between the guidelines. The agreement between the two appraisers is almost perfect (intraclass correlation coefficients higher than 0.80). A considerable proportion of the recommendations is based on low-quality or very-low-quality evidence or is even based on working group expert opinion.ConclusionsIn summary, the majority of the recommendations are based on low-quality evidence, and further confirmation is needed. Furthermore, guideline developers should pay more attention to methodological quality, especially in the Stakeholder Involvement domain and the Applicability domain.

Tight channel sandstone gas reservoirs are mainly characterized by low porosity and permeability to ultra-low porosity and permeability, strong heterogeneity, and slow energy supply rate in the later stage, resulting in small gas well control reserves, and fast decline rate of gas well pressure and production. Therefore, it is urgent to carry out targeted research on production decline. In this paper, from the perspective of percolation mechanics, a mathematical model of low-velocity non-Darcy unstable percolation in tight channel sandstone gas reservoir is established, a diagram of the relationship between non-Darcy effect, flow boundary characteristics, and dynamic bottom-hole flow is established, and the dynamic influencing factors of bottom hole flow are analyzed. From a seepage mechanics point of view, this paper establishes a tight sandstone gas reservoir river unstable low-speed non-darcy seepage flow mathematical model of non-darcy effect and flow boundary characteristics and the relationship between the bottom hole flow dynamic chart and analysis of bottom hole flow dynamic influence factors, research shows that start-up pressure gradient, skin factor, the closed boundary of tight sandstone gas reservoir river bottom hole flow dynamic effect is bigger, The research content of this paper has certain guiding significance for realizing the effective development of tight channel sandstone gas reservoir.

A simple method was proposed for preparing the dialdehyde-β-cyclodextrin (DA-β-CD) cross-linked carboxymethyl chitosan (CMCS) hydrogels for drug delivery. DA-β-CD was yielded from the sodium periodate oxidation of β-CD. Phenolphthalein (PhP) was adopted as a model drug to study the drug loading and releasing properties of the obtained hydrogels. The results show that the ability of the hydrogel to load drug is affected by the aldehyde content of DA-β-CD. The inclusion constant of DA-β-CD toward PhP is lower than that of the original β-CD and decreased with the rising of the aldehyde content. An increased cross-linking degree between DA-β-CD and CMCS slows the PhP release to some extent. In comparison with glyoxal/CMCS, DA-β-CD/CMCS presents better PhP release properties. Only 19.2 % of PhP loaded in glyoxal/CMCS was released within 24 h. Half of PhP loaded in DA-β-CD/CMCS was released in 2 h and about 90 % was released within 12 h.

The modified cellulose nanocrystals (CNCs) are expected to achieve fast and efficient decolorization of colored effluents. In this study, CNCs were surface-modified by grafting polymerization of acryloyloxyethyltrimethyl ammonium chloride (AETMAC) with the initiator of ceric ammonium nitrate (CAN). The optimum scheme to synthesize poly acryloyloxyethyltrimethyl ammonium chloride) (PAETMAC)-grafted CNCs (PAETMAC-g-CNCs) with the highest cationicity of 31.2% was determined from the orthogonal test as 4/1 (w/w) of AETMAC/CNCs, 0.01 mg/L of CAN, 50 °C and 5 h. Zeta potential, particle size, FT-IR and 13C-NMR characterizations manifested the successful introduction of PAETMAC on CNCs. XRD proved the same cellulose I of PAETMAC-g-CNCs as CNCs. As new eco-friendly flocculants, PAETMAC-g-CNCs were tested to decolorize 100 mg/L of neutral reactive blue 19 (RB 19) solutions. The results show that the higher the cationicity of PAETMAC-g-CNCs is, the less amount is needed for getting the maximum color removal. The widest flocculation window from 30 to 100 mg/L is acquired using PAETMAC-g-CNCs2 with the medium cationicity of 21.1%. Moreover, PAETMAC-g-CNCs2 is less sensitive to the pH and ion concentration of dye solutions due to its increased colloidal stability in electrolytes, acids and/or bases. It can work on a wide pH range and is applicable to treat high salt concentration effluents. The color removal efficiency is over 80% at pH 3–9 and NaCl concentration up to 60 g/L. The high crystallinity of PAETMAC-g-CNCs2 and the PAETMAC grafts promote the growth of dye-containing flocs and accelerate the flocs’ precipitation. PAETMAC-g-CNCs2 can rapidly decolorize the RB 19 solutions, which is desirable for industrial applications.

The reaction stability is a challenge in the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation of cellulose. Carbonate buffer solution (Na2CO3/NaHCO3) was used to study pH effects on stability of the oxidation reaction in this work. The structure and morphology of cellulose fibers were characterized by XRD and SEM techniques, respectively. It was found that the carboxyl content of oxidized cellulose was changed with different composition ratio of buffer solutions. The highest carboxyl content was obtained at the molar ratio of 7:3. The NaClO addition, as well as reaction temperature, affected the process of the oxidation reaction. The carboxylate content of the oxidized cellulose was increased as the temperature and NaClO consumption increased. However, both temperature and NaClO consumption have negative effect on yield. SEM results showed that the morphology of oxidized cellulose fibers was significantly changed at high reaction temperature. XRD showed that the oxidized cellulose fibers maintained the crystal structure of cellulose I. However, the crystallinity was decreased from 56.4 to 40.8 % with increasing oxidation temperature from 25 to 40 °C.

The aim of the present work was to investigate the influence of Cu substitution on the physicochemical properties of LaCo1−xCuxO3 (x = 0, 0.1, and 0.2) prepared by the sol−gel method, to clarify the relation between perovskite properties and their catalytic behaviors in the catalytic wet aerobic oxidation (CWAO) of lignin. X-ray diffraction (XRD), temperature-programmed reduction of H2 (H2-TPR), and X-ray photoelectron spectroscopy (XPS) indicated that Cu and Co were finely dispersed on the perovskite framework of the samples and an interaction between the Cu2+ and Co3+ sites in the perovskite lattice occurred. The percentages of surface chemisorbed oxygen species were 64.2, 75.2, and 81.1%, when x = 0, 0.1, and 0.2, respectively, obtained from O 1s XPS, indicating that the content of chemisorbed oxygen was improved with the increased content of Cu2+ in the mixed oxides. The samples were applied to the CWAO of lignin, and the experiments illustrated that the catalyst activity improved with an increase in ...

Venous thromboembolism (VTE) is a common vascular disorder with high mortality and morbidity. Clinical nurses are a pivotal group that can serve as first-line health care providers. Lack of knowledge about VTE is an important barrier to effective nursing performance. This study aimed to determine nurses’ knowledge of VTE prophylaxis through a nationwide survey across China, to understand gaps between current knowledge, and guidelines, and to help improve clinical nursing. The survey included 5 topics with 68 items on VTE, including basic knowledge, risk assessment, basic prophylaxis, physical prophylaxis, and pharmacological prophylaxis. The survey was distributed to 106 AAA-grade hospitals throughout China; 5218 valid questionnaires were submitted for analysis. There were 5097 women and 121 men respondents, with average age 30.29 ± 8.60 years. The average rate of correct responses regarding VTE knowledge was 59.90 ± 15.63%; 77.81% of subjects answered more than half of the survey items correctly. Better knowledge about thromboprophylaxis was observed among nurses who were more highly educated, more experienced, had received continuing education, intensive care unit (ICU), and lead nurses. Correct response rates were 68.39 ± 17.03%, 60.35 ± 21.01%, 75.51 ± 22.85%, 41.72 ± 17.47%, and 46.01 ± 21.22% for basic knowledge, risk assessment, basic prophylaxis, physical prophylaxis, and pharmacological prophylaxis, respectively. Respondents showed satisfactory results regarding basic prophylaxis, basic knowledge, and risk assessment for VTE; respondents had poorer knowledge regarding physical and pharmacological prophylaxis. Better mastery of knowledge about thromboprophylaxis was observed among nurses who were more highly educated, more experienced, had received continuous education, ICU, and lead nurses. This study suggested that nurse trainers should develop comprehensive educational programs that focus on low correct rate aspects. Higher-level continuous education could improve nurses’ knowledge of thromboprophylaxis.

There is a commercial need to increase the amount of industrial produced lignin. An 86.24 wt.% formic acid solution with 0.2 M H 2 SO 4 as the catalyst was used to isolate the lignin of dewaxed wheat straw at different residence times and reaction temperatures. Lignin was extracted and purified separately from hydrolysates and residual solids after treatment. The lignin obtained has been characterized by FTIR (Fourier transform infrared), GPC (Gel permeation chromatography), and 1 H NMR (Nuclear magnetic resonance). Results from these analyses indicated that oxidative cleavage of bonds in the lignin macromolecule has occurred during the formic acid treatment, leading to formation of oligomers of lignin with lower molecular weight. Moreover, it was found that guaiacyl unit is the main structure, the content of syringyl unit is higher than that of the hydroxybenzyl unit and β-O-4 together with β-5 ether bonds is also identified in the molecular structure of lignin of wheat straw obtained from the formic acid process.

The perovskite-type oxide catalyst LaCoO3, prepared by the sol−gel method, was tested for catalytic wet oxidation (CWAO) of lignin to aromatic aldehydes. The lignin conversion and yield of each aromatic aldehyde were significantly enhanced by the catalytic process, compared to the noncatalytic process. A mechanism involving the reaction of lignin molecules with adsorbed oxygen surface sites, Co(surf)3+O2−, was proposed on the basis of experimental observations, yielding the cycle of Co(surf)3+ → Co(surf)2+ → Co(surf)3+O2− → Co(surf)3+. The formation rates of the intermediates quinonemethide and hydroperoxide were the rate-determining steps. The activity and perovskite-type structure of the LaCoO3 catalyst did not undergo any obvious changes after the five successive reactions.

Bamboo fiber dissolution and hydrolysis in formic acid were studied. After hydrolysis, formic acid can be recovered in a clean state and reused. Solid water-soluble sugars were obtained. After being dipped into the formic acid solution for 30 min, the bamboo fibers started to swell. After one hour, the bamboo fibers gradually started to dissolve in the formic acid solution. The color of the liquor/solution turned green and dark. In the end, the bamboo fibers became thoroughly dissolved in the liquor after four hours. There was a clear hierarchical tissue structure on the fiber surface, as observed by AFM before treatment. The differential structure disappeared after 30 min of treatment. The fiber surface became plump and glossy. After six hours reaction at 60°C, the solid sugar mixture recovered contained glucose, cellobiose, cellotriose, cellotetrose, cellopentose and cellohexaose. A significant fraction of the sugar products consisted of monomeric glucose. More than 54.5% of the bamboo fiber mass had been transformed into monomeric glucose.

The perovskite-type oxide catalyst LaMnO3 prepared by the sol–gel method was found to be an efficient heterogeneous and recyclable catalyst for the wet aerobic oxidation of lignin to aromatic aldehydes. The lignin conversion rate and the yield of each aromatic aldehyde were enhanced significantly by the catalytic process as compared with the non-catalyzed process. Moreover, the activity, specific surface area and perovskite-type structure of the LaMnO3 catalyst remained nearly unchanged after five successive recycles of catalytic reactions.

The hydrolysis of degreased cotton in formic acid has been studied in this paper. Hydrochloric acid is added as a catalyst. The crystalline index of degreased cotton decreases gradually with the increase in treatment time. The effects of the reaction temperature (from 55 to 65 °C) and reaction time (from 2 to 9 h) on hydrolysis have been evaluated. The hydrolysis of cellulose and degradation of glucose increase with the increases in reaction time and temperature. The optimal conditions for the hydrolysis of degreased cotton is found to be at 65 °C for 5 h. Under the optimal conditions, 23% of the degreased cotton is turned into glucose. The maximum transformation ratio of degreased cotton to reducing sugars is 32%.

Isolated pulmonary valve endocarditis (IPE) is an uncommon clinical entity. We reported 4 cases of IPE without underlying heart diseases that required surgical interventions. Two of the present patients had predisposing factors that included a history of abdominal surgery in Case 1 and intravenous drug abuse in Case 3. All four patients presented with persistent fever together with pulmonary symptoms despite appropriate antibiotic management. Three of the patients underwent elective pulmonary valve repair, but Case 3 underwent an urgent surgical intervention due to uncontrolled septic shock. Pulmonary valve repair was performed using autologous pericardial patch in all 4 patients. All of them had immediate postoperative recovery and satisfactory outcomes in the follow-up.

Solitary extramedullary plasmacytoma located in the thorax is a rare tumor. We present a 21-year-old patient who was diagnosed with a mediastinal solitary extramedullary plasmacytoma. Complete resection of the tumor with reconstruction of the right pulmonary artery and superior vena cava was performed. The patient is alive without evidence of recurrence 8 months after the operation. Extensive resection and reconstructive surgery with the addition of radiotherapy can prolong the patient's life.

Cardiac pheochromocytoma with multiple endocrine neoplasia syndrome (MENS) is rare. We present a rare case of concurrent cardiac pheochromocytoma and pituitary adenoma, a rare variant of the MEN syndromes and a review of the literature with special emphasis on diagnosis and treatment. Different from the single MENS type I or type II, Variant MENS’ symptoms and signs are so nontypical that it is easy to make a misdiagnosis or missed diagnosis. One patient with variant MENS was treated surgically and relevant case data were collected. The perioperative course was uneventful. At 24-month follow-up, catecholamine levels returned to normal and no symptoms of pheochromocytoma was found. Cardiac pheochromocytoma with Multiple Endocrine Neoplasia can be treated by operation with good prognosis. Surgical removal to provide relief or effective control of symptoms is the treatment of choice.

TEMPO-oxidized cellulose nanofibers (TOCNs) were used as nanofillers in this work. Composite nanofibers of polyvinyl alcohol (PVA)/waterborne polyurethane (WPU) reinforced with TOCNs were produced by electrospinning. The reinforcing capability of TOCNs was investigated by tensile tests. Scanning electron microscopy (SEM), X-ray diffraction, and thermogravimetry analyses were also carried out in order to characterize the appearance, crystallinity, and reinforcing effect of the cellulose nanofibers. SEM results showed that PVA/WPU/TOCNs composite nanofibers presented a highly homogeneous dispersion of TOCNs. The reinforced composites had about 44% increase in their mechanical properties with addition of only 5 wt % of TOCNs while about 42% decrease in elongation at break. The TOCNs reinforced composite nanofibers were more thermally stable than pure PVA/WPU nanofibers. The development of crystalline structure in the composite fibers was observed by XRD. Since PVA, WPU, and TOCNs are hydrophilic, non-toxic, and biocompatible, and therefore, these nanocomposite nanofibers could be used for tissue scaffolding, filtration materials, and medical industries as wound dressing materials. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41051.

An autonomous helicopter with a vision system onboard to track ground targets can accomplish very important tasks like inspection and surveillance. The autonomous helicopter target tracking system is a interdisciplinary complex system. A typical autonomous helicopter target tracking system using vision sensors usually includes five major component: a navigation system, a flight controller, a active vision system, a target state estimator and a helicopter guidance law. In this paper, we focus on target state estimator and helicopter guidance law. It is assumed that the target moves on a flat ground, so the relative position between the target and the helicopter can be measured by a monocular vision system. Kalman filter is used to estimate the state of the target based on the vision measurements. A new guidance law inspired by velocity pursuit guidance and car-following control is proposed to guide the helicopter to follow the moving target. The tracking system is tested in a virtual reality environment and the results shows that the performance of the system is satisfied.

In this paper, a velocity controller based on H ∞ loop shaping for an unmanned helicopter is presented. H ∞ loop shaping controller guaranteed the stability margin of the closed-loop system above desired level. The performance of the controller is improved using gain-scheduling of key parameters. The simulation results show that the controller is robust and has good performance.

A new image fusion algorithm, based on steerable pyramid and Pulse Coupled Neural Network (PCNN), is proposed in this paper. First, original images are decomposed into several subbands of different levels and orientations by steerable pyramid. Then, low frequency subbands are fused by weighting and high frequency subbands are fused by PCNN. The fused image is obtained by inverse steerable pyramid transform. Results testify our approach in comparison with wavelets fusion in both subjective visual effect and objective evaluation criteria while using four different pairs of test images.

Intravenous leiomyomatosis with right intracardiac extension is rare. Surgical treatment of the tumor is still controversial because of the high postoperative risk of morbidity and mortality. We describe a series of 5 patients with these lesions who underwent elective operations with different strategies, including one-staged or two-staged resections and cardiopulmonary bypass with beating heart, cardioplegic arrest, or deep hypothermic circulatory arrest. We believe that this report represents one of the largest series of patients encountered in a single institution. In conclusion, radical resection is always possible and the outcomes are satisfactory with planned surgery.

Numerical simulation of boiling heat transfer of a horizontal tube is important. It can provide insight into the modeling of boiling phenomena and help select the right models to predict heat transfer for industrial applications such as in kettle reboilers. In this study, heat transfer characteristics of convective boiling on the outside of a horizontal tube immersed in a large saturated liquid with upward velocity is studied numerically by using finite volume method with the mixture model in multiphase flow. Turbulence is modeled by the standard κ – e model in mixture of multiphase. For different heat fluxes with different upward flow velocities, the local angular distribution of heat transfer coefficient and void fraction around the tube are presented. The results are compared with relevant experimental data.Copyright © 2005 by ASME