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Studies of self-assembled PNIPAM films on hydrophilic and hydrophobic substrates that are grown below and above lower critical solution temperature (LCST) have been performed to understand the role of intramolecular and polymer–substrate interactions in self-assembly using near edge X-ray absorption fine structure (NEXAFS) spectroscopy, atomic-force microscopic (AFM) and density functional theory (DFT). The NEXAFS spectra suggest that the polymer chains are oriented similarly on hydrophilic as well as hydrophobic substrate although the chains were having different morphologies in the solution, whereas, AFM studies shows that the morphology of the polymer chains on the two substrates are widely different. NEXAFS absorption spectra for free molecule and that with effects of substrate were calculated using DFT. The results show that on hydrophobic substrate polymer–substrate interaction is stronger as compared to that with hydrophilic one, however, for both cases this interaction plays dominant role over the intramolecular interaction for the orientation of the chains on the substrate. Matching of the calculated and experimental NEXAFS spectra shows on both types of substrates only a fraction of the attached molecules are oriented. Effect of external force on polymer substrate attachment was studied with the spin-coated films on hydrophilic substrate. Our results show that in this case substrate attachment plays an important role unlike the case of self-assembly on hydrophilic substrate, where the polymer–substrate interaction is weak. [ABSTRACT FROM AUTHOR]

In this work, we will report a method to prepare porous ZrO and ZrO/AlO macrobeads using cation-exchange resins with sulfonate groups as templates. The preparation process involves metal ion-loading, ammonia-precipitation, and calcination at an appropriate temperature. Several characterization methods, such as TGA, XRD, SEM with EDX, TEM and N adsorption and desorption, were used to characterize the ZrO and ZrO/AlO macrobeads. The results showed that the porous structures of the resin templates were negatively duplicated in the two kinds of macrobeads. We found the following interesting results: (1) The ZrO/AlO macrobeads are composed of tetragonal zirconia nanocrystals that are more technologically important, while the pure ZrO macrobeads consist of a mixture of tetragonal and monoclinic zirconia. (2) In the ZrO/AlO macrobeads, the size of ZrO nanocrystals is about 5 nm smaller than that (about 19 nm) found in the pure ZrO macrobeads. (3) The ZrO/AlO macrobeads have more mesopores and, therefore, have a larger surface area than the pure ZrO macrobeads. These oxide macrobeads will have potential applications in catalysis by taking advantage of their macrobeads shape and pores structure. [ABSTRACT FROM AUTHOR]

Summary. Vectors derived from the adeno-associated viruses (AAV) have been successfully used for the long-term expression of therapeutic genes in animal models and in patients. Stable expression of the transgene in the transduced cells can be used to correct disease stemming from genetic deficiencies. One of the major advantages of these vectors is reported to be the absence of deleterious immune responses following gene transfer. However, recent studies have shown that AAV vectors elicit humoral and cellular responses against the transgene products. This review article will focus on these two unique yet converse aspects of AAV: the ability to elicit host immune response to destroy target cells containing the transduced protein and the ability to evade immune response leading to stable expression of the transduced genes. [ABSTRACT FROM AUTHOR]

Existing vibration-based approaches for damage detection are qualitative. This paper presents a novel two-step approach for characterisation of laminar damage, such as delamination in composites and thickness reduction in metallic structures due to corrosion damage. This new approach first employs a gapped smoothing method to determine the location from curvature data. The severity of damage is then determined in the second step using an inverse method by matching predictions of finite element analysis with defl ection (or curvature) data pertinent to low-frequency vibrational response. An assessment of various approaches for computing curvature reveals that wavelet transform is a promising method for simultaneously removing noise and computing curvature. Numerical simulations show that this new two-step approach is capable of quantifying the size and severity of structural damage to be used as input for a residual strength assessment. [ABSTRACT FROM AUTHOR]

The roof-to-wall connection in a house is designed to transfer the uplift and lateral loads during strong winds by providing a continuous load path from the roof to the foundation. The uplift capacity and failure mode of the connection depends on the number and type of fasteners (nails), timber species, type of framing anchor, and constructions defects. This paper presents experimental results that were used to assess the uplift capacity variation of typical roof-to-wall connections. Based on tests with two types of connections (triple grip and truss grip) assembled with two types of timber (radiata pine and spruce pine), nails (hand and gun), and framing anchors (triple grip and universal triple grip), the results show that the variation in timber species, nail, and triple grip type changes the strength and the failure modes of the connection. The strength of the connection was reduced by about 24% when the timber species was changed from radiata pine to spruce pine and the hand nail to gun nail on the triple grip connection. This study also showed that construction defects in roof-to-wall connections influence the design uplift capacity. If there are two missing nails in the hand-nailed triple grip connection (i.e., one nail on the truss and another one on the top plate) the design uplift capacity reduces by about 40% of the ideal hand-nailed triple grip connection. This study identified the critical nails and their locations required to mitigate failure of the roof-to-wall triple grip connection subject to wind loading. [ABSTRACT FROM AUTHOR]

Kinesio taping has also been used for athletes with Medial Elbow Epicondylar Tendinopathy (MET) as an additional treatment method. The purpose of this study was to determine the clinical effectiveness of Kinesio tape on maximal grip strength and absolute and related force sense in athletes with MET when applied to the medial forearm. 27 male athletes who voluntarily participated in this study were divided into a healthy group (n = 17) and a MET group (n = 10). All subjects were assessed for the maximal grip strength and grip force sense (absolute and related force sense) under 3 taping conditions: 1) without taping; 2) with placebo Kinesio taping; and 3) with Kinesio taping. No significant interaction was found between groups and taping condition in maximal grip force and related force sense error, except for absolute force sense error (p = 0.04). Both groups with absolute force sense measurements had significantly decreased errors in the placebo Kinesio taping and Kinesio taping conditions. Both taping may enhance discrimination of magnitude of grip force control (absolute force sense) in both groups when applied to the forearm. However, Kinesio taping did not change maximal grip strength in either group. The effects of Kinesio taping on other muscle functions remain to be studied. [ABSTRACT FROM AUTHOR]

Abstract. Objective:  The phagocytic recognition and clearance of the recruited inflammatory cells with prolonged survival play a pivotal role in relieving tissue inflammation and maintaining tissue homeostasis. Transgenic mice expressing Bcl-2 in mature neutrophils demonstrated that Bcl-2 attenuated neutrophil apoptosis, while the homeostasis of the neutrophil population was essentially unaffected. This result suggests that clearance of neutrophils with prolonged survival operates independently from apoptosis. Owing to the constitutive and inducible expression of Bcl-2 homologue, A1 in human neutrophils and the intolerance of preparation for the isolated human neutrophils with prolonged survival, the human promyelocytic HL60-A1 transfectants were established to study the mechanism of phagocytic recognition/clearance of the cells with prolonged survival. Materials and Methods:  The non-apoptotic cells with prolonged survival were enriched by serum withdrawal for five days and negatively isolated by annexin V-binding beads. Then, the cells were labeled with a fluorogenic marker. Monocyte-derived macrophages (MDM) were co-cultured to perform the phagocytosis assay, and flow cytometry was employed to determine the phagocytic index. Results:  In the serum-free condition, the phagocytic index of HL60-A1 transfectants was little different from that of the HL60-EGFP control, despite showing a significantly lower degree of apoptosis. While the phagocytic index of HL60-EGFP control was significantly correlated with the degree of apoptosis, the index of the HL60-A1 transfectants was less relevant to it. The phagocytic index for the annexin V-positive cells did not distinguish the two cell types. However, the phagocytic index for the annexin V-negative cells from the HL60-A1 transfectants was increased with age in days. Preincubation of MDM with the scavenger receptor inhibitor, Oxi-LDL, and the inhibitory antibodies against αvβ3, CD14 and CD36 surface molecules could attenuate the phagocytic recognition of the annexin V-positive HL60 cells but not the annexin V-negative A1 transfectants with prolonged survival. Conclusions:  This study thus suggests that a mechanism unrelated to apoptosis exists, which mediates the phagocytic clearance of the non-apoptotic cells with prolonged survival and may be associated with A1 function in the myeloid cells. [ABSTRACT FROM AUTHOR]

A positive bias temperature instability (PBTI) recovery transient technique is presented to investigate trap properties in HfSiON as high-κ gate dielectric in nMOSFETs. Both large- and small-area nMOSFETs are characterized. In a large-area device, the post-PBTI drain current exhibits a recovery transient and follows logarithmic time dependence. In a small-area device, individual trapped electron emission from HfSiON gate dielectric, which is manifested by a staircase-like drain current evolution with time, is observed during recovery. By measuring the temperature and gate voltage dependence of trapped electron emission times, the physical mechanism for PBTI recovery is developed. An analytical model based on thermally assisted tunneling can successfully reproduce measured transient characteristics. In addition, HfSiON trap properties, such as trap density and activation energy, are characterized by this method. [ABSTRACT FROM AUTHOR]