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In this letter, the effects of various material definition approaches for stator and rotor cores on the no‐load electromagnetic field calculations of a 34 MW tubular hydrogenerator are investigated, utilizing the transient motion electromagnetic field time‐step finite element (FE) method. The findings indicate that employing a linear simplified definition for the stator core material maintains high accuracy and rationality in the calculation results of the no‐load electromagnetic field and voltage waveform while offering substantially greater computational efficiency than the non‐linear definition method. Conversely, using a linear simplified definition for the magnetic pole core material of the rotor significantly increases the error margin in the results, rendering them unacceptable. [ABSTRACT FROM AUTHOR]

This article concerns the global dynamics of a continuous planar piecewise linear differential system with three zones. We give global phase portraits in the Poincaré disc and classify bifurcation diagrams under certain parametric conditions, when the dynamics of central linear zone is anti-saddle. Rich dynamical behaviors are demonstrated, from which we observe homoclinic loops appearing in three linear zones and limit cycles occurring in three linear zones which surround a node or node-focus. [ABSTRACT FROM AUTHOR]

Anisotropic ceramic microparticles have been extensively studied in various fields such as mechanical transmission, wave absorbing, structural materials, and abrasives owing to their remarkable properties. The shape of the microparticles plays an important role in their functions. Here, we presented a facile and tunable microfluidic approach to fabricate the ceramic microparticles (∼370 μm in diameter) with the bowl shape, which have been quite challenging for synthesizing to date. Double UV lights were applied to shape the microparticles. By tailoring the cross angle and the intensities of both UV lights, bowl-shaped ceramic microparticles with different opening sizes (0–340 μm) and hollow spherical ceramic microparticles with different-sized through-holes (f = 0–0.265) were fabricated. These obtained ceramic microparticles hold great potentials to be used as the micro-components in sewage filters, micro ball valves, MEMS, micro-robots, and so forth. [Display omitted] [ABSTRACT FROM AUTHOR]

Enteromorpha prolifera belonging to the chlorophyta phylum is the main pollutant of "green tide", and propagates rapidly in recent years. However, there is almost no high-value enteromorpha treatment method at present. This study aimed to extract cellulose nanocrystals (CNC) from enteromorpha and prepare the CNC reinforced films based on alginate, carrageenan and shellac for food packaging. The effects of alginate, κ-carrageenan, cellulose nanocrystals and glycerin on the CNC reinforced alginate/carrageenan films (AC films) properties were studied systematically in this work. The results showed that the mechanical properties, swelling properties, and barrier properties of the AC could be adjusted by the concentrations of the different components. In addition, response surface methodology (RSM) was used to optimize the formula of the AC used for food packaging according to the requirements of the practical application. Furthermore, in order to further improve the food packaging capacity of the composite films, shellac was added to the optimized alginate/carrageenan films (OAC films) to obtain the shellac optimized alginate/carrageenan films (SOAC films). Finally, the OAC films and SOAC films showed excellent properties to extend the storage time of chicken breast and cherry tomatoes in the food storage experiment. • Enteromorpha pollutes the environment and is the main pollutant of "green tide". • Sodium alginate and κ-carrageenan can be used to prepare the composite films. • Cellulose nanocrystals obtained from enteromorpha could reinforce the composite films. • The composite films with shellac have great potential for food packaging. [ABSTRACT FROM AUTHOR]

The ytterbium oxide (Yb3+) is found to have an extremely low work function of 2.42 eV, which is even lower than that of its metallic form Yb0 (2.64 eV). The stability of oxides makes Yb3+ an ideal electron injection material for both top-emitting and bottom-emitting organic light-emitting diodes (TOLED and BOLED). The device test data indeed show that at 1000 nit luminance, the TOLED has a 94 cd/A current efficiency and 70 lm/W power efficiency, and BOLED has a 76 cd/A and 60 lm/W efficiency, respectively. X-ray and ultraviolet photoemission spectroscopical studies indicate that the Fermi level of the metal oxide is pinned to the lowest unoccupied molecular orbital of the electron transport layer, leading to the formation of a cathode interface with an ultra-low electron injection barrier. [ABSTRACT FROM AUTHOR]

Microfibers-weaved ceramic filters are in increasing demand due to their high filtration efficiency, stable structure and remarkable ceramic properties in water and gas treatment. To date, it remains a challenge to find an effective way to weave ceramic microfibers. This work demonstrates a novel strategy that combines gel-casting and in situ cross-flow microfluidic molding to fabricate highly flexible and shape-retentive green microfibers and then weaves them before sintering. By tailoring the curing temperature and flow rate, the diameter and surface morphology of the microfiber is accordingly tuned. Besides mesh structure, the microfibers can also be weaved into more complex three-dimensional structures such as dragonfly knot, Chinese knot, etc. Benefitting from the widely used solution system and microfluidic method, this system can serve as a general and stable platform for preparing microfibers-weaved ceramic filters made from different materials, thus holds great potential in a wide range of working conditions. [ABSTRACT FROM AUTHOR]

Ceramic microparticles have great potentials in various fields such as materials engineering, biotechnology, microelectromechanical systems, etc. Morphology of the microparticle performs an important role on their application. To date, it remains difficult to find an effective and controllable way for fabricating nonspherical ceramic microparticles with 3D features. This work demonstrates a method that combines UV light lithography and single emulsion opaque-droplet-templated microfluidic molding to prepare the crescent-shaped ceramic microparticles. By tailoring the intensity of UV light and flow rate of fluid, the shapes of microparticles are accordingly tuned. Therefore, varieties of crescent-shaped microparticles and their variations have been fabricated. After sintering, the crescent-shaped alumina ceramic microparticles were obtained. Benefitting from the light absorption and scattering behavior of most ceramic nanoparticles, this system can serve as a general platform to produce crescent-shaped microparticles made from different materials, and hold great potentials for applications in microrobotics, structural materials in MEMS, and biotechnology. [ABSTRACT FROM AUTHOR]

Thrombosis of extracorporeal circuits causes significant morbidity and mortality worldwide. In this study, plasma treatment technology and chemical grafting method were used to construct heparinized surfaces on the PVC substrate, which could not only reduce thrombosis but also decrease the side effects of the direct injection of anticoagulants. The PVC substrate was modified by plasma treatment technology firstly to obtain the active surface with the hydroxyl groups used for grafting. Then, heparin was grafted onto the modified PVC surface using different grafting strategies to prepare different heparinized surfaces. The experimental results indicated that the sodium alginate (SA) and carboxymethyl chitosan (CCS) used as interlayers could significantly increase the graft density of heparin to improve the anticoagulant effects and hemocompatibility of heparinized surfaces. In addition, the modification of heparin can further improve the anticoagulant effects. The CCS/low-molecular-weight heparin (LWMH) surface has the best anticoagulant properties, which can prolong the activated partial thromboplastin time (APTT) values of human plasma for about 35 s, reduce the hemolysis rates to <0.3 %, and perform well in the in-vitro blood circulation test. The heparinized surfaces prepared in this work have great application potential in anticoagulant treatment for medical devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Magnesium (Mg) and silver (Ag) alloys are staple electrodes for organic light-emitting diodes (OLEDs). In this study, the Mg:Ag binary phase diagram is used to establish an electrode materials selection guide for both bottom- and top-emitting OLEDs. To achieve low turn-on voltage and high efficiency in bottom-emitting OLEDs, it is found that Mg:Ag cathodes must be selected from AgMg 3 Mg phase region which provides the best figure of merits in low work function and high optical reflectance. For top-emitting OLEDs, however, Mg:Ag cathodes in the AgMg 3 Mg region show large imaginary refractive index, and thus a stacked Mg:Ag/Ag is found essential to achieve optimal device performance. Furthermore, insertion of a thin LiF layer is found to create an effective charge injection cathode. In order to theoretically compute the devices' optical characteristics, a database of complex optical constants of various materials including the metals is obtained by using a spectroscopic ellipsometer. This new database is found essential for accurate device optical design and engineering. Graphical abstract Image 1 Highlights • Mg:Ag binary phase diagram provides excellent electrode selection guide for both bottom- and top-emitting OLEDs. • For bottom-emitting OLEDs, cathodes must be selected from AgMg 3 -Mg phase for low n values and low injection barrier. • For top-emitting OLEDs, cathodes must be based on a stacked Mg:Ag/Ag to produce best possible device performance. [ABSTRACT FROM AUTHOR]

Short nanopores find extensive applications, capitalizing on their high throughput and detection resolution. Ionic behaviors through long nanopores are mainly determined by charged inner-pore walls. When pore lengths decrease to sub-200 nm, charged exterior surfaces provide considerable modulation to ion current. We find that the charge status of inner-pore walls affects the modulation of ion current from charged exterior surfaces. For 50-nm-long nanopores with neutral inner-pore walls, the charged exterior surfaces on the voltage (surfaceV) and ground (surfaceG) sides enhance and inhibit the ion transport by forming ion enrichment and depletion zones inside nanopores, respectively. For nanopores with both charged inner-pore and exterior surfaces, continuous electric double layers enhance the ion transport through nanopores significantly. The charged surfaceV results in higher ion current by simultaneously weakening the ion depletion at pore entrances and enhancing the intra-pore ion enrichment. The charged surfaceG expedites the exit of ions from nanopores, resulting in a decrease in ion enrichment at pore exits. Through adjustment in the width of charged-ring regions near pore boundaries, the effective charged width of the charged exterior is explored at ∼20 nm. Our results may provide a theoretical guide for further optimizing the performance of nanopore-based applications, such as seawater desalination, biosensing, and osmotic energy conversion. [ABSTRACT FROM AUTHOR]

In charged nanopores, ionic diffusion current reflects the ionic selectivity and ionic permeability of nanopores, which determines the performance of osmotic energy conversion, i.e., the output power and efficiency. Here, theoretical predictions of the diffusive currents through cation-selective nanopores have been developed based on the investigation of diffusive ionic transport under salt gradients with simulations. The ionic diffusion current I satisfies a reciprocal relationship with the pore length I ∝ α/L (α is a constant) in long nanopores. α is determined by the cross-sectional areas of diffusion paths for anions and cations inside nanopores, which can be described with a quadratic power of the diameter, and the superposition of a quadratic power and a first power of the diameter, respectively. By using effective concentration gradients instead of nominal ones, the deviation caused by the concentration polarization can be effectively avoided in the prediction of ionic diffusion current. With developed equations of effective concentration difference and ionic diffusion current, the diffusion current across nanopores can be well predicted in cases of nanopores longer than 100 nm and without overlapping of electric double layers. Our results can provide a convenient way for the quantitative prediction of ionic diffusion currents under salt gradients. [ABSTRACT FROM AUTHOR]

Airway remodelling is an important component of chronic obstructive pulmonary disease (COPD). Neutrophil gelatinase-associated lipocalin (NGAL) from neutrophils may drive COPD epithelial–mesenchymal transition (EMT). NGAL expression was quantified in the lungs of COPD patients and bronchoalveolar lavage fluid (BALF) of ozone-treated mice. Reticular basement membrane (RBM) thickness and E-cadherin and α-smooth muscle actin (α-SMA) expression were determined in mice airways. Effects of cigarette smoke extract (CSE) and inflammatory factors on NGAL expression in human neutrophils as well as the effects of NGAL on airway structural cells was assessed. NGAL was mainly distributed in neutrophils and enhanced in lung tissues of both COPD patients and BALF of ozone-treated mice. We showed decreased E-cadherin and increased α-SMA expression in bronchial epithelium and increased RBM thickness in ozone-treated animals. In vitro, CSE, IL-1β and IL-17 enhanced NGAL mRNA expression in human neutrophils. NGAL, in turn, down-regulated the expression of E-cadherin and up-regulated α-SMA expression in 16HBE cells via the WNT/glycogensynthase kinase-3β (GSK-3β) pathway. Furthermore, NGAL promoted the proliferation and migration of human bronchial smooth muscle cells (HASMCs). The present study suggests that elevated NGAL promotes COPD airway remodelling possibly through altered EMT. NGAL may be a potential target for reversing airway obstruction and remodelling in COPD. [ABSTRACT FROM AUTHOR]

An enantioselective decarboxylative Mannich reaction of malonic acid half esters (MAHEs) with cyclic aldimines has been accomplished by employing the copper(I)/(R,R)-Ph-Box complex as chiral catalyst. The desired β-amino esters were obtained in good to high yields with excellent enantioselectivities. Furthermore, one of the corresponding Mannich products could be readily transformed into chiral chroman-4-amines without loss of enantioselectivity, which is a key intermediate of the human Bradykinin B1 receptor antagonist. [ABSTRACT FROM AUTHOR]

• We investigated the effect of preoperative DEX on intracerebral hemorrhage (ICH) • DEX reduced the damage induced by ferroptosis after ICH in mice. • DEX alleviated iron deposition and oxidative stress caused by ferroptosis. • DEX could be useful to reduce ICH-related damage. Intracerebral hemorrhage (ICH) is a devastating condition with significant morbidity and mortality for which few effective treatments are clinically available. After ICH, iron overload within the perihaematomal region can induce lethal reactive oxygen species (ROS) production and lipid peroxidation, which contribute to secondary brain injury. An iron-dependent form of non-apoptotic cell death known as ferroptosis was recently identified. Ferroptosis plays an important role in ICH pathology. It is characterized by an accumulation of iron-induced lipid ROS, which leads to intracellular oxidative stress. Dexmedetomidine (DEX), an α2-adrenergic agonist, is widely used for anesthesia, pain control, and intensive care unit sedation. DEX has numerous beneficial activities, including anti-inflammatory, anti-oxidative, and anti-cell death activities. Here, we established a mouse model of ICH using collagenase VII and evaluated the effect of DEX in preventing ICH-induced brain injury. Our study showed that administering DEX reduced the damage induced by ferroptosis after ICH by regulating iron metabolism, amino acid metabolism and lipid peroxidation processes. [ABSTRACT FROM AUTHOR]

Cascade oxa-Michael-Henry reactions of salicylaldehyde derivatives with â-nitrostyrenes catalyzed by potassium carbonate via solvent- free ball milling are demonstrated. The corresponding 3-nitro-2Hchromene products were obtained in moderate to excellent yields. This method offers significant advantages, particularly in terms of high yields, short reaction times and mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: Zeta potential of α-Al2O3 particles in electrolytes was measured and used to describe the electrical properties of nano-particles. α-Al2O3 reinforced composite coatings were prepared from electrolytes respectively from pH5, 6, 7, 8, 9 and 10 by electro-brush plating. Morphologies of the six coatings were observed in a scanning electron microscope (SEM). Some bright dots were found in the coatings prepared at pH5, 6 and 7, while no dots were found in the coatings prepared at pH8, 9 and 10. To investigate the differences, energy dispersive spectroscopy (EDS) was performed to determine the composition of bright dots in the coatings. And it was found that the bright dots were α-Al2O3 depositing in the coatings. The result indicated that α-Al2O3 particles with positive zeta potentials deposit in a different way from particles with negative zeta potentials. A new co-deposition process of nano-particles and metallic ions was introduced from the perspective of nano-particle electrical behaviors. In general, the higher the absolute value of zeta potential is, the more the nano-particles will deposit in the coatings, and the better performance the coatings will have in micro-hardness and wear resistance because of the lower size of grains. But more negative zeta potential will prevent nano-particles from depositing. [Copyright &y& Elsevier]

This study investigated the corrosion and tribocorrosion behavior of CrN and CrAlN coatings deposited on steel through direct current magnetron sputtering. Additionally, the effects of Al addition on the microstructure, corrosion inhibition, and tribocorrosion behavior of CrN coatings were evaluated. Compared with the CrN coating, the CrAlN coating exhibited a denser columnar crystal structure and a higher hardness of 23.8 GPa. The CrAlN coating reacted with water to form Al2O3 and Cr2O3 films, which enhanced its corrosion resistance. Moreover, the addition of Al enhanced the wear resistance of the CrN coating and reduced the material loss due to corrosion, wear, and their synergistic effects. The CrAlN coating exhibited a low corrosion current density of 1.14 × 10−8 A/cm2, indicating a 92% reduction compared with the CrN coating. Furthermore, under either open circuit potential or anodic accelerated tribocorrosion conditions, the CrAlN coating featured significantly lower total material loss and synergistic material loss than the CrN coating, demonstrating higher corrosion and tribocorrosion protection. [ABSTRACT FROM AUTHOR]

A rotational fluid model which can be used to describe broad vortical flows ranging from large scale to the atmospheric mesoscale and the oceanic submesoscale is studied by the symmetry group theory. After introducing one scalar-, two vector-, and two tensor potentials, we find that the Lie symmetries of the extended system include many arbitrary functions of z and {z, t}. The obtained Lie symmetries are used to find some types of exact solutions. One of exact solutions can be used to qualitatively describe the three-dimensional structure of hurricanes. [ABSTRACT FROM AUTHOR]

This study evaluates 23 (9 Chinese and 14 non-Chinese) randomized controlled trials for efficacy and side effects of Chinese herbal medicine on menopausal symptoms. Menopause was diagnosed according to western medicine criteria in all studies while seven Chinese studies and one non-Chinese study further stratified the participants using traditional Chinese medical diagnosis "Zheng differentiation." Efficacy was reported by all 9 Chinese and 9/14 non-Chinese papers. Side effects and adverse events were generally mild and infrequent. Only ten severe adverse events were reported, two with possible association with the therapy. CH M did not increase the endometrial thickness, a common side effect of hormone therapy. None of the studies investigated long-term side effects. Critical analysis revealed that (1) high-quality studies on efficacy of Chinese herbal medicine for menopausal syndrome are rare and have the drawback of lacking traditional Chinese medicine diagnosis (Zheng-differentiation). (2) Chinese herbal medicine may be effective for at least some menopausal symptoms while side effects are likely less than hormone therapy. (3) All these findings need to be confirmed in further well-designed comprehensive studies meeting the standard of evidence-based medicine and including Zheng-differentiation of traditional Chinese medicine. [ABSTRACT FROM AUTHOR]

Some simple special Bäcklund transformation theorems are proposed and utilized to obtain exact solutions for the (2+1)-dimensional Euler equation. It is found that the (2+1)-dimensional Euler equation possesses abundant soliton or solitary wave structures, conoid periodic wave structures and the quasi-periodic Bessel wave structures on account of the arbitrary functions in its solutions. Moreover, all solutions of the arbitrary two dimensional nonlinear Poisson equation can be used to construct exact solutions of the (2+1)-dimensional Euler equation. [ABSTRACT FROM AUTHOR]

By means of the formal series symmetry approach proposed in [1], infinite many symmetries and the corresponding Kac-Moody-Virasoro Lie symmetry algebra of a new bilinear (2 + 1)-dimensional sinh-Gordon equation are given. Then, the obtained symmetries are used to get the symmetry reductions of the model. From one of the special reduction we know that the bilinear form of the first member of the negative Kadomtsev-Petviashvili hierarchy is not only a (2 + 1)-dimensional sinh-Gordon extension but also a novel (2 + 1)-dimensional classical Boussinesq extension. [ABSTRACT FROM AUTHOR]

In this manuscript, a reduced (3+1)-dimensional nonlinear evolution equation is studied. We first construct the bilinear formalism of the equation by using the binary Bell polynomials theory, then explore a lump solution to the special case for z = x. Furthermore, a more general form of lump solution of the equation is found which possesses seven arbitrary parameters and four constraint conditions. By cutting the lump by the induced soliton(s), lumpoff and instanton/rogue wave solutions are also constructed by the more general form of lump solution. [ABSTRACT FROM AUTHOR]

Antibacterial hemostatic medical dressings have become feasible solutions in response to the challenging wound-healing process. In this study, a novel fiber-type medical dressing with excellent breathable, antibacterial, and hemostatic qualities was created using sodium alginate (SA), microcrystalline cellulose (MCC), polyvinyl alcohol (PVA), and Euphorbia humifusa Willd (EHW) based on microfluidic spinning technology, and the properties of the dressing were characterized. The orthogonal test demonstrates that PVA and MCC can enhance the mechanical properties of the fiber, which is a crucial requirement for fiber assembly to form the dressing. Moreover, the presence of EHW enhances the dressing's antibacterial and hemostatic qualities. The dressings have been proven to have potent antibacterial and hemostatic properties as well as the ability to considerably speed up wound healing and skin tissue regeneration in the in-vitro and in-vivo tests. In conclusion, this innovative fiber-type medical dressing containing SA, MCC, PVA, and EHW has enormous potential for managing wounds caused by bacteria. [ABSTRACT FROM AUTHOR]

Excessive exudation from the wound site and the difficulty of determining the state of wound healing can make medical management more difficult and, in extreme cases, lead to wound deterioration. In this study, we fabricated a pH-sensitive colorimetric chronic wound dressing with self-pumping function using electrostatic spinning technology. It consisted of three layers: a polylactic acid-curcumin (PCPLLA) hydrophobic layer, a hydrolyzed polyacrylonitrile (HPAN) transfer layer, and a polyacrylonitrile-purple kale anthocyanin (PAN-PCA) hydrophilic layer. The results showed that the preparation of porous PLLA fiber membrane loaded with 0.2 % Cur was achieved by adjusting the spinning-related parameters, which could ensure that the composite dressing had sufficient anti-inflammatory, antibacterial and antioxidant properties. The HPAN membrane treated with alkali for 30 min had significantly enhanced liquid wetting ability, and the unidirectional transport of liquid could be achieved by simple combination with the 20 um PCPLLA fiber membrane. In addition, the 4 % loaded PCA showed more obvious color difference than the colorimetric membrane. In vivo and ex vivo experiments have demonstrated the potential of multifunctional dressings for the treatment of chronic wounds. [ABSTRACT FROM AUTHOR]

Starch and plant fibers are abundant natural polymers that offer biodegradability, making them potential substitutes for plastics in certain applications, but are usually limited by its high hydrophilicity, and low mechanical performance. To address this issue, polylactic acid (PLA) is blended with cellulose and chitosan to create a waterproof film that can be applied to starch-fiber foaming biodegradable composites to enhance their water resistance properties. Here, plant fibers as a reinforcement is incorporated to the modified starch by foaming mold at 260 °C, and PLA based hydrophobic film is coated onto the surface to prepare the novel hydrophobic bio-composites. The developed bio-composite exhibits comprehensive water barrier properties, which is significantly better than that of traditional starch and cellulose based materials. Introducing PLA films decreases water vapor permeability from 766.83 g/m2·24h to 664.89 g/m2·24h, and reduce hysteresis angles from 15.57° to 8.59° within the first five minutes after exposure to moisture. The water absorption rate of PLA films also decreases significantly from 12.3 % to 7.9 %. Additionally, incorporating hydrophobic films not only enhances overall waterproof performance but also improves mechanical properties of the bio-composites. The fabricated bio-composite demonstrates improved tensile strength from 2.09 MPa to 3.53 MPa. [ABSTRACT FROM AUTHOR]

Quaternized chitosan (QCS)-based films are garnering considerable attention owing to their multifunctional properties; however, their inherent hydrophilicity limits their application. In this study, a fluorine-free superhydrophobic surface for QCS-based film was fabricated using an easy and effective method. The film with hierarchical micro/nano structures (MN-surface) was fabricated by combining the template and spray methods. After modification with polydimethylsiloxane, the MN-surface showed excellent superhydrophobicity, with a water contact angle of 165.7° and a sliding angle of 4.2°. The air cushions captured by the hierarchical micro/nano structures reduced the contact area between water droplets and the MN-surface, giving it excellent self-cleaning ability. Additionally, the microstructures acted as a protective layer for the nanostructures, protecting them against damage during mechanical wear. Thus, the MN-surface exhibited remarkable mechanical robustness against sandpaper abrasion, tape peel-off, bending, stretching, and water flow impact. More importantly, it showed an excellent anti-adhesion effect on bacteria, thereby further lowering the risk of bacterial invasion. Consequently, the superhydrophobic QCS-based film opens up new possibilities for its application in diverse fields. [Display omitted] • The robust superhydrophobic quaternized chitosan-based film was prepared. • The surface exhibits outstanding adhesion properties and self-cleaning ability. • The formed hierarchical micro/nano structures can enhance its mechanical stability. • The surface shows good resistance to high-speed jets and continuous water flow. • The surface has significantly reduced bacterial adhesion by 95.2 %. [ABSTRACT FROM AUTHOR]

The symmetry transformation group of the bilinear negative Kadomtsev-Petviashvili system is studied by means of a direct method. The Kac-Moody-Virasoro-type Lie point symmetry algebra is found to be a special infinitesimal form of the symmetry group. [ABSTRACT FROM AUTHOR]

Using a new symmetry group theory, the transformation groups and symmetries of the general Broer–Kaup system are obtained. The results are much simpler than those obtained via the standard approaches. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to compare clinical and radiological outcomes between a short femoral cementless stem and a conventional femoral cementless stem in total hip arthroplasty in patients 70 years and older. Methods: From December 2011 and July 2013, we retrospectively reviewed 50 patients (55 hips) 70 years and older treated with a short femoral cementless stem and 53 patients (58 hips) 70 years and older treated with a conventional femoral cementless stem. Their mean age was 74 ± 13.2 years and 75 ± 10.4 years, respectively. The mean follow-up was 40 ± 3.6 months and 42 ± 5.2 month, respectively. They were pre- and postoperatively evaluated by the clinical and radiological examination. Results: There was no difference in terms of average operative time, average estimated blood loss, and average hemoglobin at discharge between the short stem and the conventional stem. No patients with the short stem had intra-operative fracture, but five patients with the conventional stem had intra-operative fracture. At final follow-up, there was no statistically significant difference in Harris Hip Score, and radiographic review level between two stems. No hip with the short stem had thigh pain, but six hips with the conventional stem had thigh pain at the final follow-up. No component was revised for aseptic loosening in either group. Conclusions: Our study demonstrated that both short cementless stem and conventional cementless stem provided stable fixation and achieved a satisfactory result in patients 70 years and older and the short cementless stem had a low incidence of thigh pain and intra-operative fracture. [ABSTRACT FROM AUTHOR]

The diverse properties reported for starch-based materials indicate their potential for use in the preparation of biodegradable flexible actuators. However, their natural brittleness and lack of durability after modification limit their practical application. Therefore, we propose a strategy for preparing flexible starch-based composites. The results of macro/micro property characterizations and molecular dynamics simulations indicated that using starch, maleic anhydride, and stearic acid (SA), the mobility of the starch chains was enhanced and retrogradation was inhibited through the synergistic effects induced by chain breaking, complex formation with SA, and esterification of the starch molecules. In addition, the elongation at break of the modified starch (MS) reached 2070 %, and considerable ductility (>1000 %) as well as well-complexed structure were maintained after six months. Furthermore, the MS was able to undergo self-healing after fracture or a temperature-controlled stiffness transition. Moreover, it underwent complete degradation in soil within 30 d. Finally, an actuator was prepared by doping the MS with nano-Fe 3 O 4 particles to realize a dual magnetic and optical response. Dynamic monitoring was also achieved based on the electrical signal, thereby demonstrating the broad application scope of this material in the development of biodegradable flexible actuators. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • We utilized sodium alginate and dopamine copolymers as a functional platform for grafting SBMA to obtain a surface coating. • The swelling and nanomechanical properties of brushes were investigated based on the AFM technique. • The adhesion and friction coefficient of the pDASA-SBMA brush coatings can be reduced by 80 % and 91 %, respectively. Clinical applications of interventional catheters suffer from poor lubricity and nonspecific protein adhesion, which can cause severe damage to soft tissues and even life-threatening injuries. With the proposed strategy in the grafting of sulfobetaine methacrylate (SBMA) zwitterionic polymer brushes using dopamine (DA) and sodium alginate (SA) as an intermediate layer, the pDASA-SBMA brush coatings with a controlled increase in density and thickness were prepared by tuning the grafting time. Based on the atomic force microscopy (AFM) technique, we systematically investigate the effect of variations in structural parameters on the swelling and nanomechanical properties of brushes. In particular, the dependence of the lateral deformability of brush chains on structural parameters and the viscoelastic relaxation behavior of the brush chains to recover their equilibrium conformation after deformation are elucidated, both of which have an impact on friction measurements. The experimental results show that the coating adhesion and friction coefficient in pure water decrease with the increase in grafting time, which is caused by the increase in hydration lubrication capacity of dense and thick brushes, as well as the weakening of lateral deformability. With the grafting of 24 h, the adhesion and friction coefficient of the coating can be reduced by 80 % and 91 %, respectively, compared to the unmodified surfaces. With the significant friction reduction and anti-adhesion effects, the proposed surface coating technique can find versatile applications in high-performance interventional catheters. [ABSTRACT FROM AUTHOR]

Post-stroke depression (PSD) severely affects recovery in patients with intracerebral hemorrhage (ICH). Although hydrogen gas (H 2) exerts excellent neuroprotective effects in patients with ICH, there are sex-based differences in H 2 efficacy in several diseases. Herein, we determined whether estrogen increases susceptibility to the neuroprotective effects of H 2 in males with ICH-induced depression. A rodent model of ICH in the basal ganglia was established using autologous blood injection (30 μL). Mice were treated with 2.9% H 2 for 2 h daily for 3 days post-ICH. Estrogen (1 mg/kg) was administered by subcutaneous injection daily for 3 days to male mice post-ICH. Thirty days post-ICH, PSD was evaluated by sucrose preference, forced swimming, and 3-chamber social tests. Following the completion of behavioral tests, levels of superoxide dismutase (SOD) and reactive oxygen species (ROS), astrocytic activation, phosphorylated (p)–NF–κB-positive astrocytes, p–NF–κB, p-IKKβ, IL-1β, and IL-6 expression were determined. Compared with female mice, H 2 administration post-ICH exhibited fewer neuroprotective effects, including decreased sucrose consumption and time spent sniffing a novel mouse, increased immobility time, downregulated total SOD content, upregulated ROS content and p–NF–κB levels, and elevated astrocyte branches, whereas estrogen enhanced the neuroprotective effects of H 2 in male mice. A reduced number of p–NF–κB-positive astrocytes, downregulated expression of p–NF–κB, p-IKKβ, IL-1β, and IL-6 in the amygdala were demonstrated in ICH-males treated with estrogen plus H 2. Estrogen was responsible for increased H 2 sensitivity in male mice with ICH. The underlying mechanism may be associated with the suppression of NF-κB signaling in astrocytes. • Hydrogen gas (H 2) exerts excellent neuroprotective effects in patients with ICH. • There were gender-based differences in neuroprotective effects of H 2 against ICH-induced depression. • Suppression of NF-κB signaling in astrocytes was invovled in H 2 sensitivity in male with ICH. [ABSTRACT FROM AUTHOR]

Unlike thermoplastic petroleum-based materials, starch-based materials rely on aqueous systems but are incapable of hot melting, resulting in low processing efficiency and limited large-scale industrial applications. In this study, the combination of α-amylase liquefaction and urea plasticization was used for the first time to obtain enzymatic thermoplastic starch (ETPS) for hot melting by changing the molecular chain of starch. ETPS showed an apparent hot melting phenomenon when heated below 200 °C. Differential scanning calorimetry revealed that heat absorption peaks were obviously reduced, and the hot melting phenomenon occurred easily depending on the combination of enzymatic hydrolysis and plasticization. Dynamic mechanical analysis indicated that the combined modification effectively increased the number of freely movable chains. The red shift of -OH stretching vibration peaks indicated the formation of strengthened hydrogen bonds in ETPS. X-ray diffraction showed that the crystallinity of ETPS was reduced to 5.68 %, effectively reducing the regenerative phenomenon. Gel permeation chromatography revealed that the molecular weight of ETPS decreased, and the entanglements between molecular chains were reduced. A tensile test showed that the elongation at break of ETPS was as high as 235.29 %, which was much higher than those of enzymatic hydrolysis starch and thermoplastic starch. [Display omitted] [ABSTRACT FROM AUTHOR]

Comprehensively understanding the albumin and fibrinogen adsorption behaviors is of fundamental significance for blood-contacting devices to effectively prevent the proteins adsorption. First, a controllable superhydrophobic surface presented great repellence to different liquids with water contact angle 165.2°, plasma contact angle 154.8° and blood contact angle 152.1°. Secondly, the albumin and fibrinogen adhesion tests indicated that the pure titanium surface was fully covered by the proteins layer while only a small amount of the proteins adhered to the superhydrophobic surface. Furthermore, the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) model was built by considering the Lifshitz-van der Waals (LW), the Lewis acid-base (AB) and the electrostatic double-layer (EL) interactions, the positive value of total interaction energy profile suggested that an overall repulsive interaction between the protein molecules and superhydrophobic surface happened at a small separation distance. Finally, the hollow tubes with inner superhydrophobic surface were implanted into carotid artery of rabbits for two weeks. The content of N element measured by EDS mapping provide a new evidence that superhydrophobic surface owns a great resistance of the proteins absorption, and no thrombosis or blood cells adhered to the superhydrophobic surface. This research revealed the mechanism that superhydrophobic modification could effectively prevent the adsorption of plasma proteins, which could provide some theoretical basis to help design the blood-contacting devices with great hemocompatibility. [Display omitted] • A controllable superhydrophobic surface is fabricated by laser process and chemical treatment. • Anti-proteins adsorption mechanism is revealed by the protein adhesion tests and XDLVO theory. • In vivo animal test verifies the anti-proteins adsorption behavior of superhydrophobic surface. [ABSTRACT FROM AUTHOR]

The rapid development of portable precision detection methods and the crisis of insufficient blood supply worldwide has led scientists to study mechanical visualization features beyond the biochemical properties of erythrocytes. Combined evaluation of currently known biochemical biomarkers and mechanical morphological biomarkers will become the mainstream of single-cell detection in the future. To explore the mechanical morphology of erythrocytes, a microfluidic capillary system was constructed in vitro, with flow velocity and glucose concentration as the main variables, and the morphology and ability of erythrocytes to recover from deformation as the main objects of analysis. We showed the mechanical distortion of erythrocytes under various experimental conditions. Our results showed that glucose plays important roles in improving the ability of erythrocytes to recover from deformation and in repairing the damage caused to the cell membrane during the repeated squeeze process. These protective effects were also confirmed in in vivo experiments. Our results provide visual detection markers for single-cell chips and may be useful for future studies in cell aging. [ABSTRACT FROM AUTHOR]

[Display omitted] • Directional freeze-drying technology was applied to the preparation of dressings. • The double cross-linked effect enhanced the strength of the dressings. • Aligned channels allowed anisotropic dressings to absorb exudate effectively. • This dressing could significantly accelerate diabetic wound healing. Excessive biofluid around wounds can cause infection and prevent healing. In this study, an anisotropic quaternized chitosan (QC)/sodium alginate (AL)-based aerogel wound dressing was prepared via a directional freeze-drying technique inspired by the channel structure used for water transport in trees. The aligned channels provided the dressing with self-pumping ability, allowing it to rapidly and completely remove biofluids and absorb biofluids up to 1292.5 % of its own weight. To enhance the strength of the dressing, a double cross-linked network was constructed based on the QC-AL electrostatic attraction and AL-Ca2+ chelation interaction. The axial compressive strength of the double cross-linked dressing reached 207.3 kPa (ε = 50 %). In addition, the dressing exhibited strong conductive properties (conductivity = 13.0 S/m), antioxidant activities [reactive oxygen species (ROS) scavenging ability = 88.0 %], and hemostatic characteristics (blood coagulation index = 1.8 %). The dressing also exhibited powerful antibacterial performance, exhibiting over 98.0 % inhibition of E. coli and S. aureus. Experiments on diabetic mouse models revealed that the dressing considerably promoted wound healing. On day 3, the wound healing rate was 96.7 % faster in the QAC group than in the gauze group. Therefore, the developed dressing may have great potential for chronic wound care. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fully degradable chitosan-based composite film was prepared by casting method. • Four common plant fibers were successfully used to enhance the properties of films. • The films exhibited excellent mechanical, waterproof, and thermal properties. • Their basic performance indicators were favorable as food packaging materials. To provide a fully degradable food packaging film with excellent performance, a chitosan (CS)-based film containing micron-sized plant fibers was prepared by the casting method. With the addition of different plant fibers—wheat straw fiber (WF), maize straw fiber (MF), rice straw fiber (RF), and sisal fiber (SF), a significant improvement in mechanical, water resistance, water vapor barrier, and thermal properties was observed. By comparison, the most significant enhancement effect was observed in CS/SF-based film. The tensile strength and elongation at break of this film were 58.44 MPa and 14.42%, respectively. Moreover, it exhibited excellent properties such as the highest water contact angle (118°), a moisture absorption rate of 5.14%, a low water vapor transmission rate (110.73 g·m-2·d-1), and high thermal stability. Considering the sustainability and attractive physical properties, the improved films showed great potential for food packaging. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) bioprinting is a novel technology utilizing biocompatible materials, cells, drugs, etc. as basic microcomponents to form 3D artificial structures and is believed as a promising method for regenerative medicine. Droplet-based bioprinting can precisely generate microspheres and manipulate them into organized structures with high fidelity. Biocompatible hydrogels are usually used as bioinks in 3D bioprinting, however, the viscosity of the bioink could be increased due to the additives such as cells, drugs, nutrient factors and other functional polymers in some particular applications, making it difficult to form monodispersed microspheres from high-viscosity bioink at the orifice of the nozzle. In this work, we reported a novel microfluidic-based printing nozzle to prepare monodispersed microspheres from high-viscosity bioink using the phase-inversion method. Different flowing conditions can be achieved by changing the flow rates of the fluids to form monodispersed solid and hollow microspheres using the same nozzle. The diameter of the microspheres can be tuned by changing the flow rate ratio and the size distribution of the microspheres is narrow. The prepared calcium alginate microspheres could also act as micro-carriers in drug delivery. [ABSTRACT FROM AUTHOR]

The dipole orientation of a light-emitting molecule dictates the external quantum efficiency (EQE) of an organic light emitting diode (OLED). In this paper, we studied both experimental and theoretical relationships between dipole orientation and measurable optical properties of working OLEDs. Theoretical electroluminescence (EL) spectrum, EQE, and luminance angle distribution are simulated by incorporating the dipole radiation pattern into Fabry- Pérot cavity theory with horizontal dipole ratio as a variable parameter. The horizontal ratio is determined by optimizing the fitness of theoretical EL spectra to the experimental data and EL angular distribution. We show that the optical model proposed in this paper describes well the emission dipole dependent device optical data including EL spectra, EQEs, and EL luminance angular distributions. The emission fill factor (EFF), defined as the area ratio of EL angular distribution to the Lambertian curve, is found to follow a linear relationship with horizontal dipole ratio. These results provide a simple guide to deduce dipole orientations in working OLEDs. Image 1 • A theoretical framework is developed to determine emitters' dipole orientations in working OLEDs. • The impacts of dipole orientation on measurable optical properties are studied both experimentally and theoretically. • The area ratio of EL angular distribution to the Lambertian curve is introduced as a factor to measure horizontal dipole ratio. [ABSTRACT FROM AUTHOR]

Thermal stability is one of the key technical challenges in developing high brightness organic light-emitting diodes (OLEDs). In this study, thermal catastrophic failure, a process involving temperature-induced abrupt device breakdown, is found to have a high degree of correlation to the glass transition process of the organic molecules. It is also found that C60-organic nano-composites can be used effectively to increase the glass transition temperature of the organic small molecular thin-films leading to the improvement of the thermal stability of OLEDs. In addition, a universal mathematical formula with only one variable, concentration, is discovered to quantify well the glass transition temperatures of all C60 nano-composites. The thermal catastrophic failure temperature of OLEDs with C60 nano-composites as a hole transport layer is found to be proportional to the glass transition temperature of C60 nano-composites. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the diffusion‐induced external gelation is combined with a microfluidic technique to prepare monodisperse ZrO2 ceramic microspheres. The gelation of sol droplets is traced by fluorescence visualization of the local pH, and it illustrates the effect of the external concentration of triggering agent (tetramethylethylenediamine, TMEDA) on the formation of the gel network, which results in 3 kinds of deformation of the gel particles. The deformation mechanism mainly lies in the imbalanced Laplace pressure exerted on the gel network during the competition between the gelation and the drying processes. By regulating the concentration of TMEDA, the monodisperse ZrO2 ceramic microspheres with high sphericity can be readily fabricated. [ABSTRACT FROM AUTHOR]

In a non-crystalline molecular material, glass-transition temperature T g is typically defined by an inflection point in the specific volume (or thickness) vs. temperature plot. In this paper, the glass-transitions in thin-film organic semiconductors are investigated by using various temperature spectroscopic ellipsometer. We observed that glass transition temperatures in organic thin films are characterized by a disruptive change in thickness vs. temperature plot. In order to modify the glass transition temperature of an organic semiconductor, we also made composite thin-films by inclusion of another organic molecule with higher T g . We found that the transition temperature can be significantly improved by inclusion of another organic molecule. The glass-transition processes of these composite semiconductors, however, also proceed in a disruptive manner, in stark contrast to typical polymeric materials. Despite this disruptive glass transition behavior, the experimental T g of the composite semiconductors are found to follow precisely a simple inverse sum equation of constituent temperatures with their respective weight factors. [ABSTRACT FROM AUTHOR]

An efficient organic near-infrared (NIR) to visible upconversion imaging device is obtained by integrating a photoactive buffer layer between two organic light-emitting diodes in a tandem configuration. As both types of photo-carriers (electrons and holes) are harvested to generate visible photons, this tandem device exhibits a significantly higher On/Off switching and has higher photon-photon conversion efficiency than conventional upconversion devices. We show that a high 5% photon-photon conversion rate is possible by optimizing the various functional layers in the tandem structure. We also demonstrate that a pixel-less NIR imaging chip can be made simply by using a large area single tandem organic upconversion device. [ABSTRACT FROM AUTHOR]

Thick ReO 3 film (>30 nm) is found to serve as an active hole-injecting layer as well as a passive buffer layer to suppress point discharge of Ag anode. This buffered Ag electrode enables fabrication of transparent organic light emitting diodes (TOLEDs). The excellent conductivity of ReO 3 , second only to metal amongst oxide semiconductors, is made possible to use a thick hole-injecting buffer layer. The use of thick ReO 3 layer alleviates strong local electric field on a rough electrode surface. For device optical design, the transfer matrix method is used to provide theoretical guidance on electrode fabrication. Based on microcavity theory in TOLEDs, the optical path parameters are also optimized to the thicknesses of different functional organic films. To test the device performance, we fabricated normal fluorescent green Alq 3 devices. The data show that TOLEDs with ReO 3 -buffered Ag electrodes have good photochromic uniformity on both sides of the devices. [ABSTRACT FROM AUTHOR]

In the field of medical research, the development of safe and effective wound dressings is a continuous goal. Chitosan (CS) is highly sought after because of its unique biocompatibility, biodegradability, antibacterial, and healing-promoting properties. The CS molecule has a significant number of active amino and hydroxyl groups; thus, making substitutions and creating derivatives with varied biochemical properties are relatively straightforward processes. This review addresses the range of functions performed by CS and its derivatives in wound care, such as haemostasis, antibacterial, antioxidant, and wound healing. Furthermore, it summarises the various types of CS-based dressings, their performance features and applications. Finally, the future directions of CS-based dressings are proposed. [Display omitted] [ABSTRACT FROM AUTHOR]

To solve the problem of environmental pollution caused by plastic food packaging films, a biodegradable chitosan-based film containing micro ramie fibre and lignin was prepared by the casting method. With the addition of different ratios of ramie fibre and lignin to the chitosan matrix, a significant improvement in mechanical, water resistance, thermal, and antioxidant properties was observed. The addition of 20 wt% ramie fibre increased the tensile strength by 29.6%. Moreover, the addition of 20 wt% of lignin increased the antioxidant activity by 288%, and reduced the water absorption by 41.2%. However, due to their high pyrolysis temperatures, there was little difference between ramie fibre and lignin in improving the thermal stability. Finally, this study compared the food preservation effects of composite films and PE films. The application evaluation results showed that the composite films were more effective. Overall, the chitosan-based films showed great potential for food packaging. [Display omitted] • Eco-friendly chitosan-based composite film was prepared by casting method. • Ramie fibre was used for the first time to reinforce chitosan-based film. • Ramie fibre reinforced the tensile strength and thermal stability of film. • Lignin enhanced the water resistance, antioxidation and thermal stability of film. • The chitosan-based composite film had great potential for meat packaging. [ABSTRACT FROM AUTHOR]

Highlights: [•] Low concentrations of NH4Cl/CO(NH2)2 enhanced the reductive transformation of PCP. [•] High concentrations of NH4Cl/CO(NH2)2 inhibited the reductive transformation of PCP. [•] For the genus Shewanella, all concentrations of CO(NH2)2 showed enhancement effects. [•] The variation in the trends of PCP transformation and in the abundance of the genus Dehalobacter was consistent. [•] Both NH4Cl and CO(NH2)2 had inhibitory effects on the growth of the genus Comamonas. [ABSTRACT FROM AUTHOR]

Reductive dechlorination is a crucial pathway for anaerobic biodegradation of highly chlorinated organic contaminants. Under an anoxic environment, reductive dechlorination of organic contaminants can be affected by many redox processes such as nitrate reduction and iron reduction. In the present study, batch incubation experiments were conducted to investigate the effect of nitrate addition on reductive dechlorination of PCP in paddy soil with consideration of iron transformation. Study results demonstrate that low concentrations (0, 0.5 and 1 mM) of nitrate addition can enhance the reductive dechlorination of PCP and Fe(III) reduction, while high concentrations (5, 10, 20 and 30 mM) of nitrate addition caused the contrary. Significant positive correlations between PCP degradation rates and the formation rates of dissolved Fe(II) (pearson correlation coefficients r = 0.965) and HCl-extractable Fe(II) (r = 0.921) suggested that Fe(III) reduction may enhance PCP dechlorination. Furthermore, consistent variation trends of PCP degradation and the abundances of the genus Comamonas, capable of Fe(III) reduction coupled to reductive dechlorination, and of the genus Dehalobacter indicated the occurrence of microbial community variation induced by nitrate addition as a response to PCP dechlorination. [Copyright &y& Elsevier]

Abstract: The kinetics of the reduction dissolution of iron oxides was studied by using Klebsiella pneumoniae L17 in a pH 7.0 bicarbonate buffer. The microbial reduction of various iron oxides was measured in the absence and presence of AQDS (9,10-anthraquinone-2,6-disulfonic acid), and the results of their rates vs. the surface areas of iron oxides suggested that the iron oxide reduction rate by L17 was obviously affected by the surface area but did not completely depend on it especially for hydrous ferric oxide. Increasing the crystalline degree of hematite decreased the rate of iron reduction, indicating that a higher crystalline degree inhibited microbial iron reduction. Increasing the AQDS concentration significantly increased the rate of HFO reduction, which suggested that the addition of AQDS significantly accelerated the microbial reduction of crystalline Fe(III) oxides. From the increased production of AH2DS (2,6-anthrahydroquinone disulfonate) and cell numbers, it can be concluded that the enhancement may be because of the growth in cells and abiotic Fe(III) reduction by AH2DS. X-ray diffraction, Fourier transform infrared spectra and scanning electron microscopy all indicated that secondary minerals (e.g., vivianite (Fe3(PO4)2) and siderite (FeCO3)) were the biogenic Fe(II) solids formed upon the bioreduction of iron oxides. [Copyright &y& Elsevier]

Molecular orientation in organic semiconductors plays a critical role in maximizing external quantum efficiencies of organic light-emitting diodes. It was generally believed that the molecular packing of organic semiconductors is either amorphous or liquid-crystal-like with a preferred molecular orientation distributed uniformly throughout the film. In this paper, however, we report that the orientation of organic molecules in physical-vapor deposited films varies drastically depending on thickness. The thermal stability of the molecular network, measured by its characteristic glass transition temperature, also varies as a function of the film thickness. Based on a two-layered film-structure model, we propose a simple function to quantify the molecular dipole orientation S parameter as a function of film thickness. This function describes well experimental data. In addition to contributing to external quantum efficiency, the molecular orientation parameter S is found to have a strong impact on disruptive change in material density after thermal anneal and glass transition. Image 1 • The molecular orientation dipole S in organic semiconductor films is found to depend on thickness. • An empirical equation relating film's glass transition temperature to thickness is reported. • A linear relation between molecular orientation dipole S and density change in annealed organic thin-films is observed. [ABSTRACT FROM AUTHOR]