Porous hierarchical activated carbons (HACs) exhibit fascinating physical properties and are promising for supercapacitor applications. Facile and universal methods are required to produce high ...performance HACs on a large scale to boost their practical applications. An economical and template free method has been used to prepare HACs from lignocellulosic agricultural wastes with different contents of cellulose. These amorphous HACs exhibit high conductivity, a large specific surface area, and promising potentials for high performance supercapacitors. This study suggests the feasibility for facile and scalable conversion of inexpensive and earth-abundant agricultural wastes into high value-added carbon materials for energy storage applications.
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•Hierarchical activated carbons (HACs) were prepared from three different agricultural wastes via a template free method.•HACs exhibited similar microstructures but notably different chemical compositions.•These HACs demonstrated surface-chemistry dependent electrochemical properties.
This study was carried out to develop a new type of modified starch based on α-amylase and glucoamylase. The structural and chemical characteristics of the porous starch were determined by ...Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The potential application of the porous starch as an adsorbent was evaluated using methyl violet as an adsorbed model. The adsorption capacity was optimized by investigating the reaction factors, including the mass ratio of α-amylase to glucoamylase (mα-amylase/mglucoamylase), the mass ratio of total amount of enzymes to starch (menzyme/mSt), the ratio of liquid volume to starch mass (VH2O/mSt), pH value of the reaction solution, enzymatic reaction temperature, and enzymatic reaction time. The hydrolysis ratio of each sample was also determined to investigate the effect of different reaction conditions on the hydrolysis degree. The results suggest that the porous starch has a more excellent adsorption capacity than the native starch, and may be expected to have wide potential applications in many fields.
Gamma-hydroxybutyric acid (GHB), a drug of abuse, is a substrate of monocarboxylate transporters (MCTs). Sodium-coupled monocarboxylate transporter 1 (SMCT1; SLC5A8) is expressed in kidney, thyroid ...gland, neurons, and intestinal tract and exhibits substrate specificity similar to that of the proton-dependent MCT (SLC16A) family. The role of SMCT1 in GHB disposition has not been determined. In this study we characterized the driving force, transport kinetics, and inhibitors of GHB uptake, as well as expression of SMCT and MCT isoforms, in rat thyroid follicular (FRTL-5) cells. GHB, as well as the monocarboxylates butyrate and d-lactate, exhibited sodium-dependent uptake at pH 7.4, which could be described with a simple Michaelis-Menten equation plus a diffusional component K(m) 0.68 +/- 0.30 mM, V(max) 3.50 +/- 1.58 nmol . mg(-1) . min(-1), and diffusional clearance (P) 0.25 +/- 0.08 microl . mg(-1) . min(-1). In the absence of sodium, GHB uptake was significantly increased at lower pH, suggesting proton-gradient dependent transport. Reverse transcriptase-polymerase chain reaction and Western analyses demonstrated the expression of SMCT1, MCT1, and MCT2 in FRTL-5 cells, supporting the activity results. Sodium-dependent GHB uptake in FRTL-5 cells was inhibited by MCT substrates (d-lactate, l-lactate, pyruvate, and butyrate), nonsteroidal anti-inflammatory drugs (ibuprofen, ketoprofen, and naproxen), and probenecid. IC(50) values for l-lactate, ibuprofen, ketoprofen, and probenecid were 101, 31.6, 64.4, and 380 muM, respectively. All four inhibitors also significantly inhibited GHB uptake in rat MCT1 gene-transfected MDA/MB231 cells, suggesting they are not specific for SMCT1. Luteolin and alpha-cyano-4-hydroxycinnimate represent specific proton-dependent MCT inhibitors. Our findings indicate that GHB is a substrate for both sodium- and proton-dependent MCTs and identified specific inhibitors of MCTs.
Abstract With increasing age, the competence of the immune system to fight infections and tumors declines. Age-dependent changes have been mostly described for human CD8 T cells, raising the question ...of whether the response patterns for CD4 T cells are different. Gene expression arrays of memory CD4 T cells yielded a similar age-induced fingerprint as has been described for CD8 T cells. In cross-sectional studies, the phenotypic changes were not qualitatively different for CD4 and CD8 T cells, but occurred much more frequently in CD8 T cells. Homeostatic stability partially explained this lesser age sensitivity of CD4 T cells. With aging, naïve and central memory CD8 T cells were lost at the expense of phenotypically distinct CD8 effector T cells, while effector CD4 T cells did not accumulate. However, phenotypic shifts on central memory T cells were also more pronounced in CD8 T cells. This distinct stability in cell surface marker expression can be reproduced in vitro. The data show that CD8 T cells are age sensitive by at least two partially independent mechanisms: fragile homeostatic control and gene expression instability in a large set of regulatory cell surface molecules.
In this work, a series of hydrogels were prepared by copolymerization of (2-dimethylamino) ethyl methacrylate (DMAEMA) and 3-acrylamidephenylboronic acid (AAPBA). The structure of the resultant ...hydrogels was studied by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The experimental results from swelling studies revealed that the hydrogels displayed definite glucose sensitivity under physiological conditions, as well as sharp changes in the mesh size of their network as a function of the pH and temperature of the swelling media. Bovine serum albumin (BSA) was selected as a model compound when examining protein release from hydrogels. The results suggested that the temperature, pH and glucose concentration of buffer solutions greatly influenced release profiles.
Hemorrhagic shock is the primary cause of death in patients with severe trauma, and the development of rapid and efficient hemostatic methods is of great significance in saving the lives of trauma ...patients. In this study, a polycaprolactone (PCL) nanofiber membrane was prepared by electrospinning. A PCL-PDA loading system was developed by modifying the surface of polydopamine (PDA), using inspiration from mussel adhesion protein, and the efficient and stable loading of thrombin (TB) was realized to ensure the bioactivity of TB. The new thrombin loading system overcomes the disadvantages of harsh storage conditions, poor strength, and ease of falling off, and it can use thrombin to start a rapid coagulation cascade reaction, which has the characteristics of fast hemostasis, good biocompatibility, high safety, and a wide range of hemostasis. The physicochemical properties and biocompatibility of the PCL-PDA-TB membrane were verified by scanning electron microscopy, the cell proliferation test, the cell adhesion test, and the extract cytotoxicity test. Red blood cell adhesion, platelet adhesion, dynamic coagulation time, and animal models all verified the coagulation effect of the PCL-PDA-TB membrane. Therefore, the PCL-PDA-TB membrane has great potential in wound hemostasis applications, and should be widely used in various traumatic hemostatic scenarios.
T cell-dependent B-cell responses decline with age, suggesting defective CD4 T-cell function. CD4 memory T cells from individuals older than 65 y displayed increased and sustained transcription of ...the dual-specific phosphatase 4 (DUSP4) that shortened expression of CD40-ligand (CD40L) and inducible T-cell costimulator (ICOS) (both P < 0.001) and decreased production of IL-4, IL-17A, and IL-21 (all P < 0.001) after in vitro activation. In vivo after influenza vaccination, activated CD4 T cells from elderly individuals had increased DUSP4 transcription (P = 0.002), which inversely correlated with the expression of CD40L (r = 0.65, P = 0.002), ICOS (r = 0.57, P = 0.008), and IL-4 (r = 0.66, P = 0.001). In CD4 KO mice reconstituted with DUSP4 OT-II T cells, DUSP4 had a negative effect on the expansion of antigen-specific B cells (P = 0.003) and the production of ova-specific antibodies (P = 0.03) after immunization. Silencing of DUSP4 in memory CD4 T cells improved CD40L (P < 0.001), IL-4 (P = 0.007), and IL-21 (P = 0.04) expression significantly more in the elderly than young adults. Consequently, the ability of CD4 memory T cells to support B-cell differentiation that was impaired in the elderly (P = 0.004) was restored. Our data suggest that increased DUSP4 expression in activated T cells in the elderly in part accounts for defective adaptive immune responses.
Many marketing problems require accurately predicting the outcome of a process or the future state of a system. In this paper, we investigate the ability of the support vector machine to predict ...outcomes in emerging environments in marketing, such as automated modeling, mass-produced models, intelligent software agents, and data mining. The support vector machine (SVM) is a semiparametric technique with origins in the machine-learning literature of computer science. Its approach to prediction differs markedly from that of standard parametric models. We explore these differences and benchmark the SVM's prediction hit-rates against those from the multinomial logit model. Because there are few applications of the SVM in marketing, we develop a framework to position it against current modeling techniques and to assess its weaknesses as well as its strengths.
A simple method has been developed to prepare smart P(
N,
N-diethylacrylamide-co-methacrylic acid) (P(DEA-co-MAA)) microspheres that consist of well-defined temperature-sensitive cores and pH ...sensitive shells. The microgels have been prepared by surfactant-free emulsion polymerization using water as the solvent. The core–shell hydrogel microspheres have been characterized by Fourier transform infrared (FTIR) spectroscopy, UV spectrometry, dynamic light scattering (DLS) and transmission electron micrograph (TEM). Preliminary characterization of the biocompatibility of hydrogel microspheres has been done by the cytotoxicity assays using the HeLa human breast cancer cell line as probes. The in vitro drug release indicates that drug release rate, encapsulation efficiency (EE) and release kinetics depend upon the pH value and copolymer composition. According to this study, the hydrogel microspheres based on P(DEA-co-MAA) could serve as suitable candidate for drug site-specific carrier in intestine.
For ferromagnets, varying from simple metals to strongly correlated oxides,the critical behaviors near the Curie temperature (TC ) can be grouped into several universal classes. In this paper, we ...report an unusual critical behavior in manganese nitrides Cu1-x NMn3+x (0.1 ≤ x ≤ 0.4). Although the critical behavior below TC can be well described by mean field (MF) theory, robust critical fluctuations beyond the expectations of any universal classes are observed above TC in x = 0.1. The critical fluctuations become weaker when x increases, and the MF-like critical behavior is finally restored at x = 0.4. In addition, the paramagnetic susceptibility of all the samples deviates from the Curie-Weiss (CW) law just above TC . This deviation is gradually smeared as x increases. The short-range antiferromagnetic ordering above TC revealed by our electron spin resonance measurement explains both the unusual critical behavior and the breakdown of the CW law.
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