In situ studies of strain-induced crystallization in unfilled and multiwalled carbon nanotube (MWCNT)-filled natural rubber (NR) were carried out by using synchrotron wide-angle X-ray diffraction ...(WAXD). Synchrotron WAXD results indicate that more nuclei appear in the MWCNT-filled NR sample, leading to higher crystallinity, lower onset strain of crystallization, and remarkable enhancement in tensile strength. During deformation, despite the amorphous chains remaining in isotropic orientation, the domains of larger scale (10−100 nm) with high network chain density in the NR matrix are oriented. The MWCNTs induce significant variation of this orientational process, and it is monitored by the stearic acid (SA) crystallites, which are effective nanoprobes of the amorphous phase. The results indicate that a small amount of MWCNTs and SA crystallites can be used as new tools to analyze the microstructural orientation of NR during deformation. The results also yield new insight into the strain-induced crystallization mechanism.
Given the highly heterogeneous character of brain malignancies and the associated implication for its proper diagnosis and treatment, finding biomarkers that better characterize this disease from a ...molecular standpoint is imperative. In this study, we evaluated CD146 as a potential molecular target for diagnosis and targeted therapy of glioblastoma multiforme (GBM), the most common and lethal brain malignancy. YY146, an anti-CD146 monoclonal antibody, was generated and radiolabeled for noninvasive positron-emission tomography (PET) imaging of orthotopic GBM models. (64)Cu-labeled YY146 preferentially accumulated in the tumors of mice bearing U87MG xenografts, which allowed the acquisition of high-contrast PET images of small tumor nodules (∼ 2 mm). Additionally, we found that tumor uptake correlated with the levels of CD146 expression in a highly specific manner. We also explored the potential therapeutic effects of YY146 on the cancer stem cell (CSC) and epithelial-to-mesenchymal (EMT) properties of U87MG cells, demonstrating that YY146 can mitigate those aggressive phenotypes. Using YY146 as the primary antibody, we performed histological studies of World Health Organization (WHO) grades I through IV primary gliomas. The positive correlation found between CD146-positive staining and high tumor grade (χ(2) = 9.028; P = 0.029) concurred with the GBM data available in The Cancer Genome Atlas (TCGA) and validated the clinical value of YY146. In addition, we demonstrate that YY146 can be used to detect CD146 in various cancer cell lines and human resected tumor tissues of multiple other tumor types (gastric, ovarian, liver, and lung), indicating a broad applicability of YY146 in solid tumors.
We propose a simple but rapid strategy to fabricate self-crosslinked dual-crosslinking elastomers (SCDCEs) with high mechanical properties. The SCDCEs are synthesized through one-pot copolymerization ...of Butyl acrylate (BA), acrylic amide (AM), and 3-Methacryloxypropyltrimethoxysilane (MEMO). Both the amino group on AM and the methoxy group on MEMO can be self-crosslinked after polymerization to form a dual-network crosslink consisting of hydrogen bonds crosslink and Si-O-Si covalent bonds crosslink. The SCDC endow optimal elastomer with high mechanical properties (the tensile strength is 6MPa and elongation at break is 490%) as the hydrogen bonds crosslink can serve as sacrificial construction to dissipate stress energy, while covalent crosslinking networks can ensure the elasticity and strength of the material. These two networks also contribute to the recoverability of the elastomers, leading them to recover their original shape and mechanical properties after being subjected to deformation in a short time.
In order to improve the durability of asphalt pavement, low-temperature fracture performance of AC-13 asphalt mixture with different fiber types were studied by three-point bending fracture test ...under different temperatures and presawed positions. Test results show that the improvement effect of basalt fiber is obvious and stable. The improvement effect of polyester fiber is not obvious to resist I crack, and the resistance effect of I-II compound crack is obvious. Lignin fiber mixed in the asphalt mixture has no obvious effect on improving the crack resistance property under low temperature. Fiber cooperated with asphalt mixture can improve the ability of low-temperature fracture performance, while the improvement degree is effected by fiber type. Low-temperature fracture performance of asphalt mixture improves with the increase of temperature within a certain temperature range. The presawed position has significant effect on the low-temperature fracture performance of asphalt mixture. The larger the horizontal distance of the presawed position and center load is, the stronger the low-temperature fracture performance of asphalt mixture presents.
Our dynamic mechanical measurements in the glass–rubber transition zone of polyisobutylene (PIB), expressed in terms of the relaxation spectrum H(τ) and loss tangent (tan δ), have found an additional ...shoulder. Following the interpretation of previous works, the shoulder is attributed to the sub-Rouse modes, which account for motions intermediate in length scale to the Rouse and local segmental modes. The fact that the sub-Rouse modes are well resolved in PIB and not in other amorphous polymers was traced to its weak intermolecular coupling, which ultimately originates from the compact and symmetrical structure of its repeat unit. We test this interpretation further by studying the change on adding liquid paraffin (LP) to PIB, which should disrupt the effective chain packing of undiluted PIB. We found on adding LP to PIB that the softening dispersion becomes narrower, and eventually the disappearance of the shoulder. The effect is due to the mobility of entropic Rouse modes enhanced significantly more than that of the sub-Rouse modes and the enthalpic local segmental motion on increasing the weight fraction of LP. Thus, the Rouse modes get closer to the sub-Rouse modes and local segmental motion. Incorporation of LP does not reduce much the intermolecular coupling, as evidenced by the small change of glass transition temperature. On the other hand, the disruption of the effective chain packing of PIB by adding LP endows higher mobility to the Rouse modes with longer motional units, while it has little effect on the local segmental relaxation and the sub-Rouse modes. Consequently, there is the narrowing of the softening dispersion and eventually the disappearance of the shoulder in H(τ) and tan δ. The result supports the compact and symmetric chemical structure of the repeat unit of PIB, and the efficient chain packing is the root cause that engenders the broad softening dispersion, and the observation of the sub-Rouse modes in H(τ) and tan δ. Positron annihilation lifetime spectra are presented to show the average size and concentration of the free-volume holes increase with incorporation of LP and the disruption of the effective chain packing of PIB.
To investigate the spatial distribution of 10-year incidence of diagnosed type 2 diabetes mellitus (T2DM) and its association with obesity and physical inactivity at a reginal level breakdown.
...Demographic, behavioral, medical and pharmaceutical and diagnosed T2DM incidence data were collected from a cohort of 232,064 participants who were free of diabetes at enrolment in the 45 and Up Study, conducted in the state of New South Wales (NSW), Australia. We examined the geographical trend and correlation between obesity prevalence, physical inactivity rate and age-and-gender-adjusted cumulative incidence of T2DM, aggregated based on geographical regions.
The T2DM incidence, prevalence of obesity and physical inactivity rate at baseline were 6.32%, 20.24%, and 18.7%, respectively. The spatial variation of T2DM incidence was significant (Moran's I=0.52; p<0.01), with the lowest incidence of 2.76% in Richmond Valley-Coastal and the highest of 12.27% in Mount Druitt. T2DM incidence was significantly correlated with the prevalence of obesity (Spearman r=0.62, p<0.001), percentage of participants having five sessions of physical activities or less per week (r=0.79, p<0.001) and percentage of participants walked to work (r=-0.44, p<0.001). The geographical variations in obesity prevalence and physical inactivity rate resembled the geographical variation in the incidence of T2DM.
The spatial distribution of T2DM incidence is significantly associated with the geographical prevalence of obesity and physical inactivity rate. Regional campaigns advocating the importance of physical activities in response to the alarming T2DM epidemic should be promoted.
The mitochondrial calcium-activated potassium channel (mitoK(Ca)) and the mitochondrial ATP-sensitive potassium channel (mitoK(ATP)) are both involved in cardiac preconditioning. Here, we examined ...whether these two channels are also involved in ischemic or pharmacological postconditioning. Using Langendorff perfusion, rat hearts were made hypoxic for 45 min and then reoxygenated for 30 min. Ischemic postconditioning (IPT) was achieved through application of 3 cycles of 10 s of reperfusion and 10 s of ischemia before reoxygenation, with and without paxilline (Pax; a mitoK(Ca) blocker) or 5-hydroxydecanoate (5-HD; a mitoK(ATP) blocker). Pharmacological postconditioning was carried out for 5 min at the onset of reoxygenation using NS1619 (a mitoK(Ca) opener) or diazoxide (Dia; a mitoK(ATP) opener). Pax and 5-HD abolished IPT-induced cardioprotection from reoxygenation injury, whereas administration of NS1619 or Dia significantly improved cardiac contractile activity and reduced aspartate aminotransferase (an index of myocyte injury) release following reoxygenation. In addition, isolated rat myocytes were loaded with tetramethylrhodamine methyl ester (TMRE; fluorescent mitochondrial membrane potential indicator) and 2',7'-dichlorofluorescein DCFH; fluorescent reactive oxygen species (ROS) indicator or Fluo-4-acetoxymethyl ester (Fluo-4-AM; fluorescent calcium indicator). When TMRE-loaded myocytes were laser illuminated, the DCFH and Fluo-4 fluorescence increased, and TMRE fluorescence decreased. These effects were significantly inhibited by NS1619 and Dia. We therefore conclude that IPT may protect the heart through activation of mitoK(ATP) and mitoK(Ca) channels, and that opening of these channels at the onset of reoxygenation protects the heart from reoxygenation injury, most likely by reducing excess generation of ROS and the resultant Ca(2+) overload.
•Fiber effects on asphalt's low-temp properties studied via bending/SEM tests.•0.4 % polyester fibers boost asphalt's crack resistance in salt freeze–thaw.•4 freshwater cycles predict asphalt's ...long-term low-temp performance in dry-wet states.•6 saltwater cycles at 13.25 % predict asphalt's low-temp performance in dry-wet states.•Digital image correlation (DIC) technique was used to characterize the horizontal strain at the crack concentration zone of the specimen.
Given the current insufficient understanding of the low-temperature crack resistance performance and crack evolution patterns of asphalt mixtures under chlorinated salt wet-dry coupling environments, this study aims to fill this knowledge gap. We employed SMA-13 asphalt mixtures modified with different dosages of polyester fibers (0 %, 0.3 %, 0.35 %, 0.4 %, 0.45 %, 0.5 %) and tested their low-temperature crack resistance by conducting 0 to 8 wet-dry cycles in pure water and a 13.25 % chlorinated salt solution, to explore the improvement effect of polyester fibers on the performance of asphalt mixtures in such environments. The results indicate that an increase in the number of wet-dry cycles leads to a degradation of crack resistance performance across all fiber dosages, especially under the influence of chlorinated salt wet-dry coupling, where the adverse effects are more pronounced. Fracture energy analysis further confirms that 4 and 6 cycles of wet-dry cycling are effective indicators for evaluating the attenuation of low-temperature crack resistance under the long-term impact of wet-dry cycling. Through Digital Image Correlation (DIC) and Scanning Electron Microscopy (SEM) analyses, this study reveals the significant impact of wet-dry cycling on crack evolution and identifies 0.4 % as the optimal dosage of polyester fibers, significantly enhancing the low-temperature crack resistance performance of asphalt mixtures.
A shallow-water reverberation model is developed based on Bass perturbation theory. The key component for shallow-water reverberation modeling, the modal backscattering matrix (MBSM), has been ...investigated and the explicit analytic expressions of the MBSM both for the scattering due to interface roughness and due to sediment volume inhomogeneities are derived. For rough interface scattering, it is shown that the angular dependence and the frequency dependence of the MBSM can be separated: the angular dependence is given by sin 2 (? m P/2)sin 2 (? n P/2), where ? m is the modal grazing angle and P is a bottom parameter related to the bottom reflection phase shift, and the frequency dependence is given by k 0 4-n , where n depends on the power spectrum of the roughness, for instance, n = 3 for Goff-Jordan spectrum. The difference between the scattering due to sediment volume inhomogeneities and the scattering due to rough interface is that there is an extra factor contributed by the vertical correlation and the exponential attenuation of the modal function weighting on the vertical direction in the sediment medium. This extra factor has some important impacts: (1) there will be, in general, a coupled angular-frequency behavior, (2) the angular pattern will decrease more rapidly at small grazing angle area, and (3) the angular pattern is no longer separable. It is shown that only for a ?thin? layer (or low frequency), the scattering due to volume inhomogeneities will have a similar behavior as the scattering due to rough interface. The significant feature of the angular pattern for both kinds of scattering is a marked departure from Lambert's law at small grazing angle area. The explicit analytic expression of the MBSM, and the differences between the two kinds of bottom scattering, given in this paper, provide the opportunity for a comprehensive model-data comparison and a better understanding of the scattering mechanism.
1P36 deletion syndrome is recognized as the most common terminal microdeletion syndrome in humans, characterized by early developmental delay and consequent intellectual disability, seizure disorder, ...and distinctive facial features. Variable deletion locations may attributed to phenotypic variability. However, the abnormal phenotypes of hematology are rarely reported in 1P36 deletion syndrome patients. The patient experienced IRH, an uncommon characteristic of 1p36 deletion syndrome. The deletion fragment of 1p36.33-p36.32, particularly the loss of GNB1 gene, has been associated with the development of pancytopenia. Genotype-phenotype correlations are valuable in identifying the genes responsible for various clinical characteristics of the syndrome by associating phenotypic variation with specific genes located within the chromosome deletion region. Genome sequencing is recommended in cases where clinical manifestations indicate the presence of a genetic disorder but pose diagnostic challenges.
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