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Poly(ethylene oxide) (PEO) is well-known for its excellent resistance to the nonspecific adsorption of proteins. However, it remains challenging to fabricate surfaces with uniform and robust coverage of PEO chains in a simple and efficient way. Simply by treating the block copolymer polystyrene-block-poly(ethylene oxide) (PS-b-PEO) in ethanol, we obtain nanoporous polymeric films with superior resistance to protein adsorption. The pores are nondestructively formed via the selective swelling-induced pore generation mechanism in which PEO microdomains embedded in PS matrix are selectively swollen in ethanol and collapsed in the subsequent air drying. Pore sizes and porosities can be typically tuned in the ranges ~20-50 nm and ~20-70%, respectively, by changing swelling durations and temperatures. Interestingly, the PEO chains are simultaneously migrated on the film surface and pore walls in the selective swelling-induced pore forming process. Atomic force microscopy examinations reveal that PEO chains are solvated when the film is wetted with water, closing the pores in the film. Thus, produced SEO films adsorb much less proteins than PS films without PEO on the surface, and also demonstrate a better fouling resistance than many reported PEO-covered surfaces prepared by other methods. [ABSTRACT FROM AUTHOR]

Sodium Chloride (NaCl) is a common porogen to be used in preparing porous scaffolds in tissue engineering. However, NaCl particles are easily broken during melt blending with the matrix polymer by conventional processing techniques, such as twin extrusion, which causes uncontrollable pore size and entrapped residues after leaching in the prepared scaffolds. To address these problems, this study reported a novel scaffold fabrication method based on self-developed vane extruder, which applies global dynamic elongational flow to the polymer compounds. We found that NaCl particles not only preserved their original size, but also could retain high loading content when been blended with poly(lactic acid) (PLA) matrix using vane extruder. Based on these high porogen composites, we are able to prepare PLA porous scaffolds with porosity as high as 93% via supercritical carbon dioxide (Sc-CO 2 ) foaming and particulate leaching hybrid method. Detailed analyses confirmed that the NaCl porogens could be completely leached within 24 h. The biocompatibility of the scaffolds prepared was verified by culturing human mesenchymal stem cells. Therefore, the proposed approach based on vane extruder compounding has great potential to be used in tissue engineering scaffold fabrication. [ABSTRACT FROM AUTHOR]

In order to address the low efficiency of traditional data-intensive extensible computing system in data source utilization and data transmission, a throughput optimization model of application layer based on parallel flow number prediction has been proposed. Firstly, for the purpose of improving accuracy of parallel flow number prediction and utilization efficiency of bottleneck link, selection method for equivalent parallel flow number has been designed; secondly, an full C order model has been established by using partial C order model and all of second order model as reference, and a low-sampling throughout optimization algorithm framework has been designed to reduce computational complexity; last, experiment based on data set of different sizes shows that prediction model of full C order model parallel flow number is more applicable to data transmission and is more efficient. [ABSTRACT FROM AUTHOR]

We demonstrate herein the use of a one-dimensional metal-organic material as a new type of electrode material for lithium-ion batteries (LIBs) in place of the classic porous three-dimensional materials, which are subject to the size of the channel for lithium-ion diffusion and blocking of the windows of the framework by organic solvents during the charging and discharging processes. Introducing a one-dimensional coordination compound can keep organic active substances insoluble in the electrolyte during the charging and discharging processes, providing a facile and general new system for further studies. The results show that both the aromatic ligand and the metal center can participate in lithium storage simultaneously, illustrating a new energy storage mechanism that has been well-characterized by X-ray photoelectron spectroscopy, electron paramagnetic resonance spectroscopy, and cyclic voltammetry. In addition, the fact that the one-dimensional chains are linked by weak hydrogen bonds rather than strong π-π stacking interactions or covalent bonds is beneficial for the release of capacity entirely without the negative effect of burying the active sites. [ABSTRACT FROM AUTHOR]

This study addresses the stability issue of a class of fractional-order switched non-linear systems. A general stability condition is established based on which two new concepts named Mittag-Leffler increment and average Mittag-Leffler increment are proposed and two alternative stability conditions are obtained. These conditions fully reveal the trade-off between each subsystem's dynamics, and the value of the fractional order. The new results are further applied to a class of fractional-order multi-agent systems with switching cooperative control laws. [ABSTRACT FROM AUTHOR]

In order to study the reasons for borehole instability, we calculated the mud density window for horizontal wells in complex formations based on logging data. From the results of the mud density window calculation, we found that for mudstone shales it decreases as the inclination angle and the azimuth increase, while for coal it took on negative values. We found that collapse and expansion are conducive to maintaining borehole stability, while in coal seams a positive mud density window can be achieved only by collapse (a decrease in the borehole diameter). It was determined that we need to increase the mud density from 1.2 to 1.4 g/cm and use drill pipes that are as small as possible for the longest possible period of time. In this case, the borehole trajectory should be determined according to the seam location and the mud density. [ABSTRACT FROM AUTHOR]

We report a new contaminating fungus of jet fuel, Penicillium restrictum, which accounted for nearly 17% of the total sequence identified from five jet fuel samples as determined by the application of Illumina MiSeq sequencing-by-synthesis. We also report the development and validation of a new loop-mediated isothermal amplification (LAMP) assay combined with a lateral flow dipstick (LFD) for the repaid detection of P. restrictum. The optimal reaction conditions and primer set for LAMP were determined using a real-time turbidimeter. The LAMP-LFD assay was 1000-fold more sensitive than traditional PCR. P. restrictum could be detected specifically using the LAMP-LFD assay, and no amplification was observed when genomic DNA from another seven fungi found in jet fuel was tested. Eleven jet fuel samples from the field were tested using the LAMP-LFD assay we developed. Seven of them were positive for the presence of P. restrictum. These results were verified by traditional microbiological detection methods. Our results indicate that the LAMP-LFD assay is a rapid, accurate and sensitive tool for the detection of P. restrictum and could represent a new template for the detection of contaminating fungi in jet fuel. [ABSTRACT FROM AUTHOR]

In this article, a new technique combining polymer dynamic processing and low temperature foaming was proposed to fabricate isotactic polypropylene (iPP) foams with nano-scale cellular structures. A self-developed loop oscillating push–pull molding (LOPPM) device was first used to fabricate the highly oriented iPP samples with shish-kebab crystalline structure. A temperature-quench batch foaming device was used to foam the shish-kebab structured iPP sample at 100 °C with supercritical carbon dioxide (sc-CO 2 ) as blowing agent. Nano pores with average size of 55.3 nm were generated during foaming, attributing to the hindrance and nucleation synergistic effects of the shish-kebab crystalline structure. The LOPPM-PP foam samples showed high ultimate tensile strength (100% higher than PP) and strain-at-break (186% higher than LOPPM-PP), and excellent impact strength (658% higher than PP). [ABSTRACT FROM AUTHOR]

High-temperature-resistant cementing material is required for wells drilled for heavy and shale-oil production by steam injection and in-situ combustion and for deep geothermal wells. Current cementing materials do not meet these requirements. A cementing material with heat resistance up to 600°C, compressive strength exceeding 60 MPa, and elasticity as low as 12 GPa was developed by the author. This material can be used for cementing both oil and gas wells. It can strongly cement formation rocks and well casings. [ABSTRACT FROM AUTHOR]

Late Cenozoic volcanism occurred in the central Myanmar basin, a region that is marked by the existence of the dextral Sagaing fault linking the eastern Himalayan Syntaxis to the north and the Andaman Sea to the south. Here we report new geochemical data of volcanic rocks from Monywa, Mt. Popa and Singu areas erupting in two distinct stages, i.e., mid-Miocene and Quaternary, respectively. While calc-alkaline rocks showing arc-like geochemical features are abundant, an apparent change in magma composition is observed between these two stages. The mid-Miocene rocks are mainly dominated by intermediate compositions (SiO 2 = 53-61 wt.%) and typical of high-K calc-alkaline nature. They exhibit uniform Sr and Nd isotopic ratios (I Sr ≈ ~ 0.705; ε Nd (T) = + 2.7 to + 1.6), suggesting a juvenile mantle origin related to the subduction of Indian oceanic lithosphere beneath this part of Asia. The Quaternary rocks consist mainly of basalts that, however, show variations in geochemical features. Three suites in this stage are observed: (1) calc-alkaline suite (basalts and basaltic andesites from Monywa and Mt. Popa: SiO 2 = 48–56 wt.%; I Sr = 0.704 to 0.705; ε Nd (T) = + 3.1 to + 2.1), originating from partial melting of a “remnant” juvenile mantle wedge, (2) alkali basalt suite I (basanites from Monywa: SiO 2 ≈ 45 wt.%; MgO = 10–12 wt.%; K 2 O ≈ 2.0 wt.%; I Sr = 0.704 to 0.705; ε Nd (T) ≈ + 3.6), interpreted as the product of small-degree melting from an amphibole lherzolite in the lithospheric mantle, and (3) alkali basalt suite II (trachybasalts from Singu: SiO 2 ≈ 51 wt.%; K 2 O = 2.6–3.5 wt.%; I Sr ≈ 0.706; ε Nd (T) = + 1.6 to + 0.9), interpreted as the product of partial melting from the asthenosphere. All processes of magma generation were related to the India–Asia collision that caused regional plate reorganization, a transition from oblique subduction to dextral movement in the Miocene, and subsequent “rollback” of the subducted Indian oceanic lithosphere in the Quaternary. Therefore, the arc volcanism ceased at ca. 15 Ma and, after a > 10-m.y. magmatic gap in the region, volcanism revived in the Quaternary with heterogeneous compositions owing to rise of the geotherm resulting from asthenospheric upwelling that caused small-degree melting of different domains in pre-Miocene subduction-enriched lithospheric mantle and the asthenosphere beneath central Myanmar. [ABSTRACT FROM AUTHOR]

Fabrication of small-diameter vascular scaffolds has been a challenge in recent years, especially scaffolds with multiple layers. In this study, two approaches were proposed to fabricate triple-layered vascular scaffolds based on the electrospinning method and the thermally induced phase separation (TIPS) method. It was found that the electrospun fibers had a compact fibrous structure that provided good mechanical properties. The porous TIPS layer had high porosity and pore interconnectivity to facilitate cell penetration; however, this structure alone could not ensure sufficient mechanical properties for surgical applications. The triple-layered scaffolds, which consisted of electrospun TPU, TIPS TPU, and electrospun PPC layers, showed the highest mechanical properties and best structure and dimensions for vascular graft applications. Preliminary endothelial cell culture results showed that the cells could attach to and proliferate on the inside surface of the scaffolds with >95% viability. [ABSTRACT FROM AUTHOR]

A novel and efficient preparation of epoxyketone intermediates for the synthesis of carfilzomib and its derivatives has been developed. Compared to reported methods, this highly stereoselective, environmentally friendly, low-cost method can be used in scaling up the synthesis of carfilzomib and its derivatives. [ABSTRACT FROM AUTHOR]

This study considers incremental stability problem of switched non-linear systems with each mode being local incrementally asymptotically stable. A new concept named 'steady-state inclusion' is proposed to describe the relations among incremental stability regions of modes. Based on such a concept, sufficient incremental stability conditions of the switched systems are established, which cover the global incremental stability as a special case. The new result is applied to synchronisation problem of coupled identical systems with switching coupling. [ABSTRACT FROM AUTHOR]

We have used a numerical simulation to study the temperature distribution, thermal stress, and thermal displacements during in-situ heating of shales. We have observed that the heater temperature and the temperature at the position of the casing do not change much, while the water temperature in the wellbore and in the region of the cement ring drops quickly. The temperature in layers below the wellbore reach the melting point of the shale after continuous heating for 10-100 hours, while it reaches the heater temperature after 1000 hours. The heating efficiency drops rapidly because of significant convection, which does not permit effective heating of the strata. At the same time, thermal expansion leads to a change in the displacement in the X direction and the equivalent stress. Both the indicated parameters reach a maximum on the well wall and remain unchanged as the distance from the borehole increases. Under these conditions, the casing - cement ring interface and the cement ring - stratum interface slip considerably, separating the two interfaces, and the equivalent stress leads to yield of the casing, the cement ring, and the stratum. The results obtained can be useful for cementing and completion of wells. [ABSTRACT FROM AUTHOR]

ABSTRACT A novel structure for dual-band substrate integrated waveguide filters is presented in this article. To obtain advantages of compact structure and good performance, complementary split-ring resonators (CSRRs) are simplified, and loaded into the waveguide surface with complementary spiral resonators (CSRs) together. As a result, two passbands below the cutoff frequency of the waveguide are obtained. Every passband has two transmission zeros and two transmission poles. This article points out that the combination of CSRRs and CSRs cannot only make the structure more compact, but also produce a positive interaction between the resonators, providing a new direction for the application of those two right/left-hand structures. To verify the presented concept, the filter is fabricated. The measured results are in good agreement with the simulation. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1-4, 2016 [ABSTRACT FROM AUTHOR]

The change from forest to agricultural land in the last three decades represents a significant shift in land use in China. This study was conducted to evaluate how change from forest to greenhouse cabbage production affected soil organic carbon (SOC) and total nitrogen (TN) stocks in surface soil. Our results showed that converting forest to greenhouse vegetable production led to increases in SOC and TN concentrations and stocks, and decreases in C:N ratio in the top soil. The accumulation rates of SOC and TN in the surface soil (0-40cm) were estimated to be 4.638 Mg ha-1 yr-1 and 1.113 Mg ha-1 yr-1 respectively, over an average period of 8 years after change of forest to greenhouse vegetable production. We conclude that greenhouse vegetable production system could be an effective strategy to improve SOC and TN stocks in the subtropical Dianchi lake watershed. [ABSTRACT FROM AUTHOR]

Triple-layered small diameter vascular scaffolds, which consisted of thermoplastic polyurethane (TPU) and silk, were fabricated in this study for the first time by combining electrospinning, braiding, and thermally induced phase separation methods. These novel vascular scaffolds, which possess three layers of different structures (nanofibrous inner layer, woven silk filament middle layer, and porous outer layer), can mimic the structure of native blood vessels. The vascular scaffolds have a desirable toe region in tensile tests and sufficient suture retention and burst pressure for vascular graft applications. Endothelial cell culture tests showed that a cell layer could form on the inner surface of the scaffold with high cell viability and favorable morphology. [ABSTRACT FROM AUTHOR]

Halloysite nanotubes (HNTs), due to their unique structures and properties, may play an important role in biomedical applications. In vitro test is usually conducted as a preliminary screening evaluation of the hemocompatibility and cytotoxicity of HNTs for its short term consuming, convenience, and less expense. In this work, HNTs were processed with anticoagulated rabbit blood to detect its blood compatibility. The result of hemolysis test shows that the hemolysis ratios are below 0.5%, indicating nonhemolysis of HNTs. Plasma recalcification time suggests that HNTs are dose-dependently contributing to blood coagulation in platelet poor plasma (PPP). The effect of platelet activation caused by HNTs was also examined by scanning electron microscopy (SEM). Meanwhile, HNTs were labeled with fluorescein isothiocyanate (FITC) to observe its intracellular distribution in A549 cells under confocal microscopy. CCK-8 test and TUNEL test of HNTs at different concentration levels were performed in vitro, respectively. Therefore, the potential usage of HNTs in medicine may be very meaningful in oral dosing, dermal application, dental uses, or medical implants. [ABSTRACT FROM AUTHOR]

The influence of stratum properties on wellbore stability was studied by numerical simulation. The results showed that the safe mud density window (SMDW) for both permeable and impermeable strata becomes narrower with increase in the ground stress non-uniformity coefficient. The probability of wellbore wall instability increases where the strata are permeable. If the ground stress non-uniformity coefficient is constant in this case, then there is a linear increase in the pressure at which stability loss and wellbore-wall collapse occur and a linear increase in stratum fracture pressure (SFP). Here, fracture pressure increases more rapidly than collapse pressure. The SMDW narrows with rise in pore pressure and widens with an increase in stratum tensile strength and the cohesive force between molecules. The SMDW is wider for permeable strata than for impermeable strata in this case. The width of the SMDW also increases with an increase in the internal friction angle, but it becomes narrower with an increase in the effective stress. The SMDW is not affected by increases in the Poisson's ratio or porosity if there is no permeation but becomes smaller if there is permeation. In the absence of a supporting force, wellbore stability decreases drastically and the formation near the wellbore also becomes unstable. [ABSTRACT FROM AUTHOR]

This paper presents a novel methodology to detect a set of more suitable attributes that may potentially contribute to emerging faults of a wind turbine. The set of attributes were selected from one-year historical data for analysis. The methodology uses the k-means clustering method to process outlier data and verifies the clustering results by comparing quartiles of boxplots, and applies the auto-associative neural networks to implement the residual approach that transforms the data to be approximately normally distributed. Hotelling T2 multivariate quality control charts are constructed for monitoring the turbine's performance and relative contribution of each attribute is calculated for the data points out of upper limits to determine the set of potential attributes. A case using the historical data and the alarm log is given and illustrates that our methodology has the advantage of detecting a set of susceptible attributes at the same time compared with only one independent attribute is monitored. [ABSTRACT FROM AUTHOR]

Hemicellulosic fractions were extracted from soybean hull with various concentrations of NaOH at 50 °C for 5 h. The chemical compositions and physicochemical properties were determined by high performance anion exchange chromatography (HPAEC), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analyzer (TGA), and 13C and 2D nuclear magnetic resonance (NMR) analysis. The crystallinity of soybean hulls treated and untreated by alkali liquid was examined by X-ray diffraction (XRD). The sugar analysis results indicated that all of the hemicellulosic preparations were heteropolysaccharides containing arabinose, galactose, glucose, xylose, and mannose. According to the spectral analysis, hemicelluloses from soybean hull were assumed to be L-arabino-4-O-methyl-D-glucurono-D-xylan. Xylose was the predominant monosaccharide in the hemicellulose fraction 1 (H1), and it ranged between 40.1% and 48.8% of the total neutral sugars. It was found that hemicellulose fraction 3 (H3) had the highest thermal stability and H1 had the lowest thermal stability. The crystallinity index (CrI) was found to be about 20.8%, 14.3%, 10.9%, and 4.7% for soybean hulls, untreated and treated with 1.5, 2.0, and 2.5 M NaOH, respectively. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented on the analysis of organometallic compounds by desorption electrospray ionization mass spectrometry in a study of a processed eggshell.

AKT1-dependent molecular pathways control diverse aspects of cellular development and adaptation, including interactions with neuronal dopaminergic signaling. If AKT1 has an impact on dopaminergic signaling, then genetic variation in AKT1 would be associated with brain phenotypes related to cortical dopaminergic function. Here, we provide evidence that a coding variation in AKT1 that affects protein expression in human B lymphoblasts influenced several brain measures related to dopaminergic function. Cognitive performance linked to frontostriatal circuitry, prefrontal physiology during executive function, and frontostriatal gray-matter volume on MRI were altered in subjects with the AKT1 variation. Moreover, on neuroimaging measures with a main effect of the AKT1 genotype, there was significant epistasis with a functional polymorphism (Val158Met) in catechol-O-methyltransferase [COMT], a gene that indexes cortical synaptic dopamine. This genetic interaction was consistent with the putative role of AKT1 in dopaminergic signaling. Supportive of an earlier tentative association of AKT1 with schizophrenia, we also found that this AKT1 variant was associated with risk for schizophrenia. These data implicate AKT1 in modulating human prefrontal-striatal structure and function and suggest that the mechanism of this effect may be coupled to dopaminergic signaling and relevant to the expression of psychosis. [ABSTRACT FROM AUTHOR]

Background: Syphilis is a sexually transmitted disease caused by Treponema pallidum, and the infection source is syphilis patients. This study aimed to estimate the incidence, mortality rate, and disability-adjusted life years (DALYs) of syphilis to improve the understanding of the current global situation of syphilis. Methods: This study collected data on syphilis incidence, mortality, and DALYs from the 2019 Global Burden of Disease database. Results: The global number of incident cases and age-standardized incidence rate (ASIR) increased from 8,845,220 (95% UI: 6,562,510–11,588,860) in 1990 to 14,114,110 (95% UI: 10,648,490–18,415,970) in 2019 and 160.03/100,000 persons (95% UI: 120.66–208.1) to 178.48/100,000 persons (95% UI: 134.94–232.34), respectively. The estimated annual percentage change (EAPC) in the ASIR was 0.16 (95% CI: 0.07–0.26). The EAPC in the ASIR associated with high and high-middle sociodemographic indices increased. The ASIR increased among males but decreased among females, and the incidence peaked among males and females between the ages of 20 and 30 years. The EAPCs in the age-standardized death rate and age-standardized DALY rate decreased. Conclusions: The incidence and ASIR of syphilis increased worldwide from 1990 to 2019. Only the regions with high and high-middle sociodemographic indices showed an increase in the ASIR. Moreover, the ASIR increased among males but decreased among females. The age-standardized death rate and DALY rate both declined worldwide. The increase in the global ASIR of syphilis is a challenge. [ABSTRACT FROM AUTHOR]

This paper presents a multidisciplinary structural optimization approach to design separation nuts with low-level pyroshock responses for aerospace. A parametric modeling method is developed to automatically construct a multibody finite element model for separation nuts according to the predefined structural parameters. A new explicit dynamics analysis workflow tailored to separation nuts is proposed to simulate the pyroshock environment efficiently. Based on a backpropagation neuron network technique, certain surrogate models are established to describe the equivalence relationship between the structural parameters and the multidisciplinary structural responses including the pyroshock, the bending stiffness, and the structural weight. Finally, a pyroshock minimization problem with the constraints of structural weight and bending stiffness is solved by using a genetic algorithm, resulting in an optimized low-pyroshock separation nut design. The comparison between the optimized structure and a reference structure shows the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Biodegradable poly(lactic acid) (PLA)based poly(butylenes succinate)(PBS) foams with open cell structure were prepared via batch foamingmethod using supercritical carbon dioxide as blowing agent. It wasfound that PLA was immiscible with PBS, and PBS phase was dispersedas tiny spheres or large domains at various concentrations. The additionof PBS reduced the viscosity of the blends. During the foaming process,the PLA/PBS interfaces acted as cell nucleation sites and the lowmelt strength PBS contributed to the formation of cell connectionchannels, which resulted in open cell structure. The investigationof PBS content and foaming temperature found that PLA/PBS (80/20)foamed at 100 °C, obtaining the highest cell opening rate (96%).Two-step depressurization foaming experiments proved that bimodalcell structure PLA/PBS foams with high cell opening rate (97%) wereable to be fabricated. [ABSTRACT FROM AUTHOR]

An increasing number of randomized controlled trials (RCTs) of acupuncture have proved the clinical benefits of acupuncture; however, there are some results that have shown negative results or placebo effects. The paper carried out an in-depth analysis on 33 RCTs in the 2011 SCI database, the quality of the reports was judged according to Jadad scores, and the “Necessary Information Included in Reporting Interventions in Clinical Trials of Acupuncture (STRICTA 2010)” was taken as the standard to analyze the rationality of the therapeutic principle. The difference between the methodology (Jadad) scores of the two types of research reports did not constitute statistical significance (P>0.05). The studies with negative results or placebo effects showed the following deficiencies with respect to intervention details: (1) incompletely rational acupoint selection; (2) inconsistent ability of acupuncturists; (3) negligible needling response to needling; (4) acupuncture treatment frequency too low in most studies; and (5) irrational setting of placebo control. Thus, the primary basis for the negative results or placebo effects of international clinical trials on acupuncture is not in the quality of the methodology, but in noncompliance with the essential requirements proposed by acupuncture theory in terms of clinical manipulation details. [ABSTRACT FROM AUTHOR]

Matrix metalloproteinase-1 (MMP-l) plays crucial roles in diseaserelated physiologies and pathological processes in the human body. We report here solution studies of MMP-l, including characterization of a series of mutants designed to bind metal in either the catalytic site or the structural site (but not both). Circular dichroism and fluorescence spectroscopy of the mutants demonstrate the importance of the structural Zn(II) in maintaining both secondary and tertiary structure, while UV-- visible, nuclear magnetic resonance, electron paramagnetic resonance, and extended Xray absorption fine structure show its presence influences the catalytic metal ion's coordination number. The mutants allow us to demonstrate convincingly the preparation of a mixed-metal analogue, CocZns-MMP-l, with Zn(II) in the structural site and Co(II) in the catalytic site. Stopped-flow fluorescence of the native form, ZncZns-MMP-l, and the mixed-metal CocZns-MMP-l analogue shows that the internal fluorescence of a nearby Trp residue is modulated with catalysis and can be used to monitor reactivity under a number of conditions, opening the door to substrate profiling. [ABSTRACT FROM AUTHOR]

Polymeric nanoparticles with glucose-responsivenessare of greatinterest in developing a self-regulated drug delivery system. In thiswork, glucose-responsive polymer vesicles were fabricated based onthe complexation between a glucosamine (GA)-containing block copolymerPEG45-b-P(Asp-co-AspGA)and a phenylboronic acid (PBA)-containing block copolymer PEG114-b-P(Asp-co-AspPBA) withα-CD/PEG45inclusion complex as the sacrificial template.The obtained polymer vesicles composed of cross-linked P(Asp-co-AspGA)/P(Asp-co-AspPBA) layer as walland PEG chains as both inner and outer coronas. The vesicular morphologywas observed by transmission electron microscopy (TEM), and the glucose-responsivenesswas investigated by monitoring the variations of hydrodynamic diameter(Dh) and light scattering intensity (LSI)in the polymer vesicle solution with glucose using dynamic light scattering(DLS). Vancomycin as a model drug was encapsulated in the polymervesicles and sugar-triggered drug release was carried out. This kindof polymer vesicle may be a promising candidate for glucose-responsivedrug delivery. [ABSTRACT FROM AUTHOR]

Background: Magnesium (Mg)-deficiency is frequently observed in Citrus plantations and is responsible for the loss of productivity and poor fruit quality. Knowledge on the effects of Mg-deficiency on upstream targets is scarce. Seedlings of 'Xuegan' [Citrus sinensis (L.) Osbeck] were irrigated with Mg-deficient (0 mM MgSO4) or Mg-sufficient (1 mM MgSO4) nutrient solution for 16 weeks. Thereafter, we first investigated the proteomic responses of C. sinensis roots and leaves to Mg-deficiency using two-dimensional electrophoresis (2-DE) in order to (a) enrich our understanding of the molecular mechanisms of plants to deal with Mg-deficiency and (b) understand the molecular mechanisms by which Mg-deficiency lead to a decrease in photosynthesis. Results: Fifty-nine upregulated and 31 downregulated protein spots were isolated in Mg-deficient leaves, while only 19 upregulated and 12 downregulated protein spots in Mg-deficient roots. Many Mg-deficiency-responsive proteins were involved in carbohydrate and energy metabolism, followed by protein metabolism, stress responses, nucleic acid metabolism, cell wall and cytoskeleton metabolism, lipid metabolism and cell transport. The larger changes in leaf proteome versus root one in response to Mg-deficiency was further supported by our observation that total soluble protein concentration was decreased by Mg-deficiency in leaves, but unaffected in roots. Mg-deficiency had decreased levels of proteins [i.e. ribulose-1,5-bisphosphate carboxylase (Rubisco), rubisco activase, oxygen evolving enhancer protein 1, photosynthetic electron transfer-like protein, ferredoxin-NADP reductase (FNR), aldolase] involved in photosynthesis, thus decreasing leaf photosynthesis. To cope with Mg-deficiency, C. sinensis leaves and roots might respond adaptively to Mg-deficiency through: improving leaf respiration and lowering root respiration, but increasing (decreasing) the levels of proteins related to ATP synthase in roots (leaves); enhancing the levels of proteins involved in reactive oxygen species (ROS) scavenging and other stress-responsive proteins; accelerating proteolytic cleavage of proteins by proteases, protein transport and amino acid metabolism; and upregulating the levels of proteins involved in cell wall and cytoskeleton metabolism. Conclusions: Our results demonstrated that proteomics were more affected by long-term Mg-deficiency in leaves than in roots, and that the adaptive responses differed between roots and leaves when exposed to long-term Mg-deficiency. Mg-deficiency decreased the levels of many proteins involved in photosynthesis, thus decreasing leaf photosynthesis. [ABSTRACT FROM AUTHOR]

Background: Magnesium (Mg)-deficiency is frequently observed in Citrus plantations and is responsible for the loss of productivity and poor fruit quality. Knowledge on the effects of Mg-deficiency on upstream targets is scarce. Seedlings of 'Xuegan' [Citrus sinensis (L.) Osbeck] were irrigated with Mg-deficient (0 mM MgSO4) or Mg-sufficient (1 mM MgSO4) nutrient solution for 16 weeks. Thereafter, we first investigated the proteomic responses of C. sinensis roots and leaves to Mg-deficiency using two-dimensional electrophoresis (2-DE) in order to (a) enrich our understanding of the molecular mechanisms of plants to deal with Mg-deficiency and (b) understand the molecular mechanisms by which Mg-deficiency lead to a decrease in photosynthesis. Results: Fifty-nine upregulated and 31 downregulated protein spots were isolated in Mg-deficient leaves, while only 19 upregulated and 12 downregulated protein spots in Mg-deficient roots. Many Mg-deficiency-responsive proteins were involved in carbohydrate and energy metabolism, followed by protein metabolism, stress responses, nucleic acid metabolism, cell wall and cytoskeleton metabolism, lipid metabolism and cell transport. The larger changes in leaf proteome versus root one in response to Mg-deficiency was further supported by our observation that total soluble protein concentration was decreased by Mg-deficiency in leaves, but unaffected in roots. Mg-deficiency had decreased levels of proteins [i.e. ribulose-1,5-bisphosphate carboxylase (Rubisco), rubisco activase, oxygen evolving enhancer protein 1, photosynthetic electron transfer-like protein, ferredoxin-NADP reductase (FNR), aldolase] involved in photosynthesis, thus decreasing leaf photosynthesis. To cope with Mg-deficiency, C. sinensis leaves and roots might respond adaptively to Mg-deficiency through: improving leaf respiration and lowering root respiration, but increasing (decreasing) the levels of proteins related to ATP synthase in roots (leaves); enhancing the levels of proteins involved in reactive oxygen species (ROS) scavenging and other stress-responsive proteins; accelerating proteolytic cleavage of proteins by proteases, protein transport and amino acid metabolism; and upregulating the levels of proteins involved in cell wall and cytoskeleton metabolism. Conclusions: Our results demonstrated that proteomics were more affected by long-term Mg-deficiency in leaves than in roots, and that the adaptive responses differed between roots and leaves when exposed to long-term Mg-deficiency. Mg-deficiency decreased the levels of many proteins involved in photosynthesis, thus decreasing leaf photosynthesis. [ABSTRACT FROM AUTHOR]

Fabrication of small diameter vascular grafts plays an important role in vascular tissue engineering. In this study, thermoplastic polyurethane (TPU)/graphene oxide (GO) scaffolds were fabricated via electrospinning at different GO contents as potential candidates for small diameter vascular grafts. In terms of mechanical and surface properties, the tensile strength, Young's modulus, and hydrophilicity of the scaffolds increased with an increase of GO content while plasma treatment dramatically improved the scaffold hydrophilicity. Mouse fibroblast (3T3) and human umbilical vein endothelial cells (HUVECs) were cultured on the scaffolds separately to study their biocompatibility and potential to be used as vascular grafts. It was found that cell viability for both types of cells, fibroblast proliferation, and HUVEC attachment were the highest at a 0.5 wt.% GO loading whereas oxygen plasma treatment also enhanced HUVEC viability and attachment significantly. In addition, the suture retention strength and burst pressure of tubular TPU/GO scaffolds containing 0.5 wt.% GO were found to meet the requirements of human blood vessels, and endothelial cells were able to attach to the inner surface of the tubular scaffolds. Platelet adhesion tests using mice blood indicated that vascular scaffolds containing 0.5% GO had low platelet adhesion and activation. Therefore, the electrospun TPU/GO tubular scaffolds have the potential to be used in vascular tissue engineering. [ABSTRACT FROM AUTHOR]

In this study, parallel-aligned poly(propylene carbonate) (PPC) microfibers with a fiber diameter of 1.48 ± 0.42 μm were prepared by electrospinning and modified by oxygen plasma treatment. Next, chitosan nanofibers with a fiber diameter size of 278 ± 98 nm were introduced into the PPC fiber mats by freeze drying. Morphological analyses showed that the PPC scaffolds treated with 0.05 mg/ml chitosan solution provided the best micro and nanofiber structure with abundant chitosan nanofibers but without the formation of films. Surface chemical properties were analyzed by X-ray photoelectron spectroscopy (XPS). The initial water contact angle of the scaffolds decreased from 122.3 ± 0.4° for neat PPC scaffolds to 53.8 ± 1.6° for scaffolds with plasma treatment and chitosan nanofibers. The mechanical properties of the scaffolds were affected by plasma treatment with Young's modulus experiencing a reduction of 63%. Meanwhile, Young's modulus experienced a 26% improvement after the introduction of chitosan nanofibers. Fibroblast cells were cultured on the scaffolds to study the effects of both the plasma treatment and the introduction of chitosan nanofibers on cell adhesion, proliferation, and morphology. The scaffolds with PPC microfibers and chitosan nanofibers showed a superior cell response in terms of cell attachment, cell proliferation, and cell–scaffold interactions over the other scaffolds. [ABSTRACT FROM AUTHOR]

Tissue engineering provides a novel and promising approach to replace damaged tissue with an artificial substitute. Porous synthetic biodegradable polymers are the preferred materials for this substitution due to their microstructure, biocompatibility, biodegradability, and low cost. As a crucial element in tissue engineering, a scaffold acts as an artificial extracellular matrix (ECM) and provides support for cell migration, differentiation, and reproduction. The fabrication of viable scaffolds, however, has been a challenge in both clinical and academic settings. Methods such as solvent casting/particle leaching, thermally induced phase separation (TIPS), electrospinning, gas foaming, and rapid prototyping (additive manufacturing) have been developed or introduced for scaffold fabrication. Each method has its own advantages and disadvantages. In this review, the commonly used synthetic polymer scaffold fabrication methods will be introduced and discussed in detail, and recent progress regarding scaffold fabrication—such as combining different scaffold fabrication methods, combining various materials, and improving current scaffold fabrication methods—will be reviewed as well. [ABSTRACT FROM PUBLISHER]

A novel Pd-catalyzed intermolecular regio- and diastereoselective fluorosulfonylation of styrenes has been developed under mild conditions. This reaction exhibits a wide range of functional-group tolerance in styrenes and arylsulfinic acids to afford various β-fluoro sulfones. Preliminary mechanistic study reveals an unusual mechanism, in which a high-valent L2PdIIIF species side-selectively reacts with a benzylic carbon radical to deliver a C-F bond. This pathway is distinct from a previously reported radical fluorination reaction. [ABSTRACT FROM AUTHOR]

Thesignificant influence of graphene oxide (GO) on the unidirectionalfoaming of poly(lactic acid) (PLA) using supercritical CO2as blowing agent was investigated in this study for the first time.Highly oriented and elongated cell structures were obtained from thePLA/GO nanocomposites foams. The thermal, rheological, and CO2absorption properties of the PLA/GO nanocomposites were studiedto investigate the effect of GO on PLA unidirectional foaming. Itwas found that the incorporation of GO improved the storage modulus,loss modulus, and complex viscosity of the PLA/GO nanocomposites significantly.The addition of GO improved the CO2absorption abilityof the nanocomposites, which caused high expansion ratio and increasedaverage cell size during foaming process. The high expansion forceby enhanced CO2absorption, high matrix viscosity of PLA/GOnanocomposites, and restriction of the mold in three directions togethercaused the formation of the highly elongated cell structure duringfoaming. [ABSTRACT FROM AUTHOR]

The global proliferation of metallo-carbapenemase-producing Enterobacteriaceae has created an unmet need for inhibitors of these enzymes. The rational design of metallo-carbapenemase inhibitors requires detailed knowledge of their catalytic mechanisms. Nine cephalosporins, structurally identical except for the systematic substitution of electron-donating and withdrawing groups in the para position of the styrylbenzene ring, were synthesized and utilized to probe the catalytic mechanism of New Delhi metallo-β-lactamase (NDM-1). Under steady-state conditions, Km values were all in the micromolar range (1.5-8.1 μM), whereas kcat values varied widely (17-220 s--1). There were large solvent deuterium isotope effects for all substrates under saturating conditions, suggesting a proton transfer is involved in the rate-limiting step. Pre-steady-state UV-visible scans demonstrated the formation of short-lived intermediates for all compounds. Hammett plots yielded reaction constants (p) of -- 0.34 ± 0.02 and -- 1.15 ± 0.08 for intermediate formation and breakdown, respectively. Temperature-dependence experiments yielded AG* values that were consistent with the Hammett results. These results establish the commonality of the formation of an azanide intermediate in the NDM-1-catalysed hydrolysis of a range cephalosporins with differing electronic properties. This intermediate is a promising target for judiciously designed β - lactam antibiotics that are poor NDM-1 substrates and inhibitors with enhanced active-site residence times. [ABSTRACT FROM AUTHOR]

Biomimeticporous poly(ε-caprolactone) (PCL) scaffolds containingchitosan nanofibers (CSNF) were produced by using a hybrid processthat combines extrusion foaming, water-soluble phase leaching, andfreeze-drying. The high porosity and interconnectivity of the scaffoldswere achieved by supercritical fluid foaming and the addition of water-solublepoly(ethylene oxide) (PEO) and sodium chloride (NaCl) as porogens.The porosity of the scaffolds after leaching was over 78%. The structureof the chitosan nanofibers introduced into the micropores of the scaffoldswas similar to the collagen bundles in the extracellular matrix (ECM).The chitosan nanofibers enhanced the compressive modulus of the scaffoldsslightly and improved the water uptake ability by as much as 35% comparedto the scaffolds without chitosan. A 3T3 fibroblast cell culture wasperformed to investigate the biocompatibility of the scaffolds, whichrevealed that the cells proliferated better on the PCL/chitosan scaffoldsthan on the PCL scaffolds. Regarding cell morphology, cells on thePCL scaffolds were rounded in the form of tumoroids, suggesting poorcell adhesion and poor cell–scaffold interactions. In contrast,cells on the PCL/chitosan scaffolds were elongated and spindle-shaped,indicating favorable cell–scaffold interactions. Therefore,the highly porous PCL scaffolds containing chitosan nanofibers fabricatedin this study have the potential to be used in tissue engineeringapplications. [ABSTRACT FROM AUTHOR]

Terrestrial laser scanning technology (TLS) is a new technique for quickly getting three-dimensional information. In this paper we research the health assessment of concrete structures with a Finite Element Method (FEM) model based on TLS. The goal focuses on the benefits of 3D TLS in the generation and calibration of FEM models, in order to build a convenient, efficient and intelligent model which can be widely used for the detection and assessment of bridges, buildings, subways and other objects. After comparing the finite element simulation with surface-based measurement data from TLS, the FEM model is determined to be acceptable with an error of less than 5%. The benefit of TLS lies mainly in the possibility of a surface-based validation of results predicted by the FEM model. [ABSTRACT FROM AUTHOR]

Spatial monitoring of the sowing date plays an important role in crop yield estimation at the regional scale. The feasibility of using polarimetric synthetic aperture radar (SAR) data for early season monitoring of the sowing dates of oilseed rape (Brassica napus L.) fields is explored in this paper. Polarimetric SAR responses of six parameters, relying on polarization decomposition methods, were investigated as a function of days after sowing (DAS) during the entire growing season, by means of five consecutive Radarsat-2 images. A near-continuous temporal evolution of these parameters was observed, based on 88 oilseed rape fields. It provided a solid basis for determining the suitable temporal window and the best polarimetric parameters for sowing date monitoring. A high sensitivity of all polarimetric parameters to the DAS at different growing stages was shown. Simple linear models could be calibrated to estimate sowing dates at early growth stages and were validated on an independent data set. Although Volume and Span parameters provided the highest sowing date estimation accuracy at the earlier growth stages, the other four parameters (Volume/Total, Odd/Total, Entropy and Alpha) were more accurate for a wider temporal window. These results demonstrate the capability and high potential of polarimetric SAR data for monitoring the sowing date of crops in the early season. [ABSTRACT FROM AUTHOR]

Surface properties of tissue engineering scaffolds such as topography, hydrophilicity, and functional groups play a vital role in cell adhesion, migration, proliferation, and apoptosis. In this study, poly(ε-caprolactone) (PCL) shish–kebab scaffolds (PCL-SK), which feature a three-dimensional structure comprised of electrospun PCL nanofibers covered by periodic, self-induced PCL crystal lamellae on the surface, was created to mimic the nanotopography of native collagen fibrils in the extracellular matrix (ECM). Two different kinds of solvents used in creating kebabs on the shish were investigated by real-time observation. It was found that the solvent solubility directly affects the formation of kebabs: the lower the solubility of the solvent, the easier the formation of the kebabs on the surface of the electrospun nanofibers. In addition, matrigel was covalently immobilized on the surface of alkaline hydrolyzed PCL and PCL-SK scaffolds to enhance their hydrophilicity. This combined approach not only mimics the nanotopography of native collagen fibrils, but also simulates the surface features of collagen fibrils for cell growth. To investigate the viability of such scaffolds, HEF1 fibroblast cell assays were conducted and the results revealed that the nanotopography of the PCL-SK scaffolds facilitated cell adhesion and proliferation. The matrigel functionalization on PCL-SK scaffolds further enhanced cellular response, which suggested elevated biocompatibility and greater potential for tissue engineering applications. [ABSTRACT FROM AUTHOR]

The reserves of oil shale are over 5 times as many as the current natural proven recoverable oil reserves in the world. It has huge potential but it is hard to obtain economic efficiency because of its low oil length and exploration difficulty. This research combines theory and experiment, evaluates the exploitation of in-situ heating of oil shale with injection fluid, which have the characteristics of high oil length, large productivity and short production cycle. For the oil shale layer with high oil length (>18%), the oil price shall at least reach 105 $/bbl (18% oil length) to maintain 10% of the internal rate of return; for the oil shale with low oil length (3.5–18%), the oil price shall at least reach 377 $/bbl (5% oil length) to maintain 10% of the internal rate of return. At present, only the oil shale with high oil length (>18%) can be exploited for in-situ heating of oil shale with injection fluid in China. [ABSTRACT FROM AUTHOR]

Background: Protein complexes are important for understanding principles of cellular organization and function. High-throughput experimental techniques have produced a large amount of protein interactions, making it possible to predict protein complexes from protein -protein interaction networks. However, most of current methods are unsupervised learning based methods which can't utilize the information of the large amount of available known complexes. Methods: We present a supervised learning-based method for predicting protein complexes in protein - protein interaction networks. The method extracts rich features from both the unweighted and weighted networks to train a Regression model, which is then used for the cliques filtering, growth, and candidate complex filtering. The model utilizes additional “uncertainty" samples and, therefore, is more discriminative when used in the complex detection algorithm. In addition, our method uses the maximal cliques found by the Cliques algorithm as the initial cliques, which has been proven to be more effective than the method of expanding from the seeding proteins used in other methods. Results: The experimental results on several PIN datasets show that in most cases the performance of our method are superior to comparable state-of-the-art protein complex detection techniques. Conclusions: The results demonstrate the several advantages of our method over other state-of-the-art techniques. Firstly, our method is a supervised learning-based method that can make full use of the information of the available known complexes instead of being only based on the topological structure of the PIN. That also means, if more training samples are provided, our method can achieve better performance than those unsupervised methods. Secondly, we design the rich feature set to describe the properties of the known complexes, which includes not only the features from the unweighted network, but also those from the weighted network built based on the Gene Ontology information. Thirdly, our Regression model utilizes additional “uncertainty" samples and, therefore, becomes more discriminative, whose effectiveness for the complex detection is indicated by our experimental results. [ABSTRACT FROM AUTHOR]

Electrospray ionization (ESI) is a powerful ionization technique with a wide range of applications. However, the analytes in low/nonpolar solvents cannot be analyzed directly in electrospray ionization-mass spectrometry (ESI-MS), because low/nonpolar solvents are incompatible with ESI, because of their low conductivity. To circumvent this problem, we introduce an electrospray-based ionization method termed solvent-assisted electrospray ionization (SAESI). With the help of electrospray solvents at the tip of the spray needle, compounds in "non-electrospray ionization-friendly" solvents can be ionized directly using solvent-assisted electrospray ionization-mass spectrometry (SAESI-MS). The key features that the assistant solvent can be chosen flexibly and makes little interference to samples lead to better ionization performance in detection of organic reaction intermediates and real-time analysis of polymers and chiral drugs separated by gel permeation chromatography (GPC) and normal phase liquid chromatography (NPLC). Furthermore, it can achieve online hydrogen/deuterium (H/D) exchange reaction and even mitigate the signal suppression caused by strong acid modifiers in liquid chromatography. In addition, all parts of this device are commercially available and it only requires two parameters to be optimized, which makes SAESI easy to handle. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effects of supplementation with dietary green tea polyphenols (GTPs) on parasite resistance and acute phase protein (APP) response to Haemonchus contortus infection in lambs. Thirty male Ujumqin lambs were randomly assigned to five treatment groups for an 8-week feeding period. Treatments included: (1) uninfected as control, (2) infected but not given GTP (INFGTP0) and (3)–(5) infected and fed 2, 4, or 6 g GTP/kg feed (dry matter basis; INFGTP2, INFGTP4, and INFGTP6, respectively). Fecal and blood samples were collected to determine fecal egg count (FEC), packed cell volume (PCV), and APP concentrations. Live weight was measured once every 2 weeks. At the end of the feeding period, lambs were slaughtered to determine the adult H. contortus burden. The results demonstrated interaction effects between treatment and sampling time on the average daily gain (ADG; P = 0.0005), FEC ( P < 0.0001), PCV ( P = 0.0005), and concentrations of serum amyloid A (SAA), haptoglobin (Hp), lipopolysaccharide binding protein (LBP), and α 1 -acid glycoprotein (α 1 AGP) ( P < 0.0001). From days 0 to 56, the ADG values for all infected lambs were lower than that of uninfected lambs, but the ADG values for all GTP-fed lambs were higher than that of INFGTP0 lambs, especially from days 28 to 42. The FECs of all GTP-fed lambs were higher than those of uninfected lambs but lower than that of INFGTP0 lambs. The PCVs of all infected lambs were lower than those of uninfected lambs, but PCV increased with increasing amounts of GTP supplementation. Furthermore, supplementation with different concentrations of GTP significantly reduced the numbers of adult H. contortus , including both males and females ( P < 0.0001), and the H. contortus burden in INFGTP6 lambs was reduced to uninfected levels. Overall, the SAA, Hp, LBP, and α 1 AGP concentrations of all infected lambs were higher than those of uninfected lambs from days 0 to 56. Two peaks in expression were observed from days 0 to 3 and at day 28, and APP concentrations of all GTP-fed lambs were lower than those of INFGTP0 lambs, except for SAA in INFGTP6 lambs. In conclusion, quantitative measurements of APP responses to H. contortus infection provide valuable diagnostic information for monitoring infection progression and treatment responses in lambs. An appropriate dose of dietary GTP supplementation can increase host resistance by reducing H. contortus burden and weight loss and suppressing blood APP expression. [ABSTRACT FROM AUTHOR]

Geographic routing is appropriate for sensor networks because of their special characteristics, such as Wireless Local Area Networks. However, the existing holes in the practical networks may probably impact the performance of geographic routing. In this paper, we employ hyperbolic Ricci flow to compute a new embedding of sensor nodes, which could achieve the conformal map of the topology of the network to virtual coordinates in hyperbolic space even if its topology contains multiple holes, and is easy to establish the corresponding routing. In actual experiments and simulations, our method has been proved valuable and feasible. [ABSTRACT FROM AUTHOR]

Nine molecular substitutional alloys with formula [Cl-BzPy][NixPt1-x(mnt)2] (x = 0.09-0.91) were prepared by mixing the isostructural [Cl-BzPy][Ni(mnt)2] and [Cl-BzPy][Pt(mnt)2] in acetonitrile according to the molar ratio of x/(1 - x), where mnt2- = maleonitriledithiolate, Cl-BzPy+ = 1-(4'-chloro-benzyl)pyridinium. Each alloy compound is isostructural with the parent compounds and shows a magnetic transition; the TC decreases linearly with the molar fraction x, indicating that TC is precisely tunable in this alloy system. [ABSTRACT FROM AUTHOR]

We studied lensless imaging due to coherent backscattering in random media both theoretically and experimentally. The point spread function of the lensless imaging system was derived. Parameters such as the volume fraction of the scatterer in the random scattering medium, the diameter of the scatterer, the distance between the object to be imaged and the surface of the random scattering medium were optimized to improve the image contrast and resolution. Moreover, for complicated objects, high contrast and quality images were achieved through the high-order intensity correlation measurement on the image plane, which may propel this imaging technique to practical applications. [ABSTRACT FROM AUTHOR]