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Objective: Electroacupuncture (EA) has a definite effect on the treatment of spinal cord injuries (SCIs), but its underlying molecular mechanism remains unclear. Meanwhile, MiR106b-5p is an autophagy- and apoptosis-related microribonucleic acid, but whether it regulates the progression of autophagy and apoptosis in SCIs is yet undetermined. As such, this study aimed to elucidate the involvement of miR-106b-5p in the EA treatment of an SCI. Methods: The miR-106b-5p level was detected by quantitative real-time polymerase chain reaction. In vitro, SH-SY5Y cells were transfected with miR-106b-5p mimics or inhibitors to regulate the miR-106b-5p expression, while in vivo, SCI rats were treated with EA for 7 days at the bilateral Zusanli (ST36) and Jiaji (EX-B2) acupoints. The motor function was evaluated using the Basso-Beattie-Bresnahan (BBB) criteria. Further, autophagic vacuoles, pathological damage, and neuronal cell morphology were observed by transmission electron microscopy, as well as by hematoxylin and eosin and Nissl staining, respectively. Results: The miR-106b-5p level, which can interact directly with Beclin-1 by influencing its expression, as well as the expressions of P62, Caspase-3, and Bax, was upregulated after an SCI, but it decreased after EA. Moreover, the ratio of LC3-II to LC3-I was upregulated after EA. EA can enhance autophagy, reduce neuronal apoptosis, and minimize motor dysfunction and histopathological deficits after an SCI. More importantly, however, all the above effects induced by EA can be reversed after an injection of miR-106-5p agomir to produce an overexpression of miR-106b-5p. Conclusion: EA treatment could downregulate miR-106b-5p to alleviate SCI-mediated injuries by promoting autophagy and inhibiting apoptosis. [ABSTRACT FROM AUTHOR]

Background: The cardiometabolic index (CMI) has been proposed as a novel indicator of cardiometabolic status. However, evidence on the relationship between CMI and diabetes mellitus (DM) risk was limited. Our study aimed to explore the relationship between CMI and DM risk among a large cohort of Japanese adults. Methods: This retrospective cohort study recruited 15453 Japanese adults without diabetes at baseline who underwent physical examinations at the Murakami Memorial Hospital between 2004 and 2015. Cox proportionalhazards regression was applied to evaluate the independent relationship between CMI and diabetes. Our study performed a generalized smooth curve fitting (penalized spline technique) and an additive model (GAM) to determine the non-linear relationship between CMI and DM risk. In addition, a set of sensitivity analyses and subgroup analyses were employed to evaluate the relationship between CMI and incident DM. Results: After adjusting for confounding covariates, CMI was positively related to the DM risk in Japanese adults (HR: 1.65, 95%CI: 1.43-1.90, P<0.0001). A series of sensitivity analyses were also employed in this study to guarantee the reliability of the findings. In addition, our study discovered a non-linear association between CMI and diabetes risk. CMI's inflection point was 1.01. A strong positive association between CMI and diabetes incidence was also discovered to the left of the inflection point (HR: 2.96, 95%CI: 1.96-4.46, P<<0.0001). However, their association was not significant when CMI was higher than 1.01 (HR: 1.27, 95%CI: 0.98-1.64, P=0.0702). Interaction analysis showed that gender, BMI, habit of exercise, and smoking status interacted with CMI. Conclusion: Increased CMI level at baseline is associated with incident DM. The association between CMI and incident DM is also non-linear. A high CMI level is associated with an increased risk for DM when CMI is below 1.01. [ABSTRACT FROM AUTHOR]

Background: The mechanisms underlying the online modulation of motor speech in Parkinson's disease (PD) have not been determined. Moreover, medical and rehabilitation interventions for PD-associated motor speech disorder (MSD) have a poor long-term prognosis.Methods: To compare risk factors in PD patients with MSD to those without MSD (non-MSD) and determine predictive independent risk factors correlated with the MSD phenotype, we enrolled 314 PD patients, including 250 with and 64 without MSD. We compared demographic, characteristic data, as well as PD-associated evaluations between the MSD group and non-MSD group.Results: Univariate analysis showed that demographic characteristics, including occupation, educational level, monthly income and speaking background; clinical characteristics, including lesions in the frontal and temporal lobes, and concurrent dysphagia; and PD-associated evaluations, including the activity of daily living (ADL) score, non-motor symptoms scale (NMSS) domain 4 score (perceptual problem), and NMSS domain 5 score (attention/memory) were all significantly different between the MSD and non-MSD group (all P < 0.05). Multivariate logistic regression analysis showed that educational level, frontal lesions, and NMSS domain 5 score (attention/memory) were independent risk factors for PD-associated MSD (all P < 0.005).Conclusions: We determined an association between MSD phenotype and cognitive impairment, reflected by low-level education and related clinical profiles. Moreover, attention and memory dysfunction may play key roles in the progression of MSD in PD patients. Further studies are required to detail the mechanism underlying abnormal speech motor modulation in PD patients. Early cognitive intervention may enhance rehabilitation management and motor speech function in patients with PD-associated MSD. [ABSTRACT FROM AUTHOR]

Verticillium wilt (VW) is a soil-borne fungal disease that is caused by Verticillium dahliae Kleb and seriously damages cotton production annually in China. To date, many efforts have beenmade to improve the resistance of upland cotton against VW, but little progress has been achieved because of a lack of resistant upland cotton to VW. G. barbadense is known to carry high resistance to VW; however, it is difficult to transfer the resistance trait from G. barbadense to upland cotton because of linkage drag and distortion in the interspecific hybrid. In this study, a chromosomal segment introgression line (CSIL), SuVR043, containing a single and homozygous chromosome segment of G. barbadense cv. H7124 D04 (Chr 22), was created and used to construct an F2 population for mapping of VW resistance quantitative trait loci (QTLs) in the greenhouse. Two major resistance QTLs against nondefoliating V. dahliae isolate Bp2, called qVW-Bp2-1 and qVW-Bp2-2, which were flanked by the markers cgr6409-ZHX37 and ZHX57-ZHX70 and explained an average of 16.38 and 22.36% of the observed phenotypic variation, respectively, were detected in three independent replicate experiments. The genetic distances from cgr6409 to ZHX37 and from ZHX57 to ZHX70 were 2.4 and 0.8 cM, respectively. By analyzing the genome sequence of the qVW-Bp2-1 and qVW-Bp2-2 regions, we determined that the accurate physical distances from cgr6409 to ZHX37 and from ZHX57 to ZHX70 in the G. barbadense genome are 254 and 140 kb, and that those spans 36 and 20 putative genes, respectively. The results of the expression analysis showed significant differences in the expression profiles of GbCYP450, GbTMEM214, and GbRLK among G. barbadense cv. H7124, CSIL SuVR043 and G. hirsutum acc. Sumian 8 at different times after inoculation with V. dahliae isolate Bp2. Virus-induced gene silencing (VIGS) analysis showed that silencing of GbCYP450 and GbTMEM214 decreased H7124 and CSIL SuVR043 resistance to VW. These results form a solid foundation for fine mapping and cloning of resistance genes in the substituted segment and will provide valuable assistance in future efforts to breed for VW resistance. [ABSTRACT FROM AUTHOR]

The Stress Associated RNA-binding protein 1 (SRP1) repressed by ABA, salt and cold encodes a C2C2-type zinc finger protein in Arabidopsis. The knock-out mutation in srp1 reduced the sensitivity of seed to ABA and salt stress during germination and post-germinative growth stages. In contrast, SRP1-overexpressing seedlings were more sensitive to ABA and salt compared to wild type plants. In the presence of ABA, the transcript levels of ABA signaling and germination-related genes including ABI3, ABI5, EM1 and EM6 were less induced in srp1 compared to WT. Interestingly, expression of ABI2 encoding a protein phosphatase 2C protein were significantly up-regulated in srp1 mutants. By in vitro analysis, SRP1 was identified as a novel RNA-binding protein directly binding to 30UTR of ABI2 mRNA. Moreover, transient expression assay proved the function of SRP1 in reducing the activity of luciferase whose coding sequence was fused with the ABI2 3'UTR. Together, it is suggested that SRP1 is involved in the ABA signaling by post-transcriptionally repressing ABI2 expression in Arabidopsis. [ABSTRACT FROM AUTHOR]

Smart materials that can respond to external stimuli are of wide-spread interest in biomedical science. Thermal-responsive shape memory polymers, a class of intelligent materials that can be fixed at a temporary shape below their transition temperature (Ttrans) and thermally triggered to resume their original shapes on demand, hold great potential as minimally invasive self-fitting tissue scaffolds or implants. The intrinsic mechanism for shape memory behavior of polymers is the freezing and activation of the long-range motion of polymer chain segments below and above Ttrans, respectively. Both Ttrans and the extent of polymer chain participation in effective elastic deformation and recovery are determined by the network composition and structure, which are also defining factors for their mechanical properties, degradability, and bioactivities. Such complexity has made it extremely challenging to achieve the ideal combination of a Ttrans slightly above physiological temperature, rapid and complete recovery, and suitable mechanical and biological properties for clinical applications. Here we report a shape memory polymer network constructed from a polyhedral oligomeric silsesquioxane nanoparticle core functionalized with eight polyester arms. The cross-linked networks comprising this macromer possessed a gigapascal-storage modulus at body temperature and a Ttran. between 42 and 48 °C. The materials could stably hold their temporary shapes for >1 year at room temperature and achieve full shape recovery ⩽51 °C in a matter of seconds. Their versatile structures allowed for tunable biodegradability and biofunctionalizability. These materials have tremendous promise for tissue engineering applications. [ABSTRACT FROM AUTHOR]

In this paper, we introduce an alternative stochastic restricted Liu estimator for the vector of parameters in a linear regression model when additional stochastic linear restrictions on the parameter vector are assumed to hold. The new estimator is a generalization of the ordinary mixed estimator (OME) (Durbin in J Am Stat Assoc 48:799–808, 1953; Theil and Goldberger in Int Econ Rev 2:65–78, 1961; Theil in J Am Stat Assoc 58:401–414, 1963) and Liu estimator proposed by Liu (Commun Stat Theory Methods 22:393–402, 1993). Necessary and sufficient conditions for the superiority of the new stochastic restricted Liu estimator over the OME, the Liu estimator and the estimator proposed by Hubert and Wijekoon (Stat Pap 47:471–479, 2006) in the mean squared error matrix (MSEM) sense are derived. Furthermore, a numerical example based on the widely analysed dataset on Portland cement (Woods et al. in Ind Eng Chem 24:1207–1241, 1932) and a Monte Carlo evaluation of the estimators are also given to illustrate some of the theoretical results. [ABSTRACT FROM AUTHOR]

One of the most promising avenues to meet the requirements of higher performance, lower cost, and smaller size in electronic systems is the embedded capacitor technology. Polymer-ceramic nanocomposites can combine the low cost, low temperature processability of polymers with the desirable electrical and dielectric properties of ceramic fillers, and have been identified as the major dielectric materials for embedded capacitors. However, the demanding requirements of mechanical properties and reliability of embedded capacitor components restrict the maximum applicable filler loading (<50 vol%) of nanocomposites and thereby limit their highest dielectric constants (<50) for real applications. In this paper, we present a study on the optimization of the epoxybarium titanate nanocomposites in order to obtain high performance, reliable embedded capacitor components. To improve the reliability of polymer-ceramic nanocomposites at a high filler loading, the epoxy matrix was modified with a secondary rubberized epoxy, which formed isolated flexible domains (island) in the continuous primary epoxy phase (sea). The effects of sea-island structure on the thermal mechanical properties, adhesion, and thermal stress reliability of embedded capacitors were systematically evaluated. The optimized, rubberized nanocomposite formulations had a high dielectric constant above 50 and successfully passed the stringent thermal stress reliability test. A high breakdown voltage of 89 MV/m and a low leakage current of about 1.9 × 10-11 A/cm2 were measured in the large area thin film capacitors. [ABSTRACT FROM AUTHOR]

A novel, photodefinable, high dielectric constant (high‐k) nanocomposite material was developed for embedded capacitor applications. It consists of SU8 as the polymer matrix and barium titanate (BT) nanoparticles as the filler. The UV absorption characteristics of BT nanoparticles were studied with a UV‐Vis spectrophotometer. The effects of BT nanoparticle size, filler loading, and UV irradiation dose on SU8 photopolymerization were systematically investigated. The dielectric properties of the photodefined SU8 nanocomposites were characterized. Embedded capacitors using the novel high dielectric constant SU8 composite photoresist were demonstrated on a flexible polyimide substrate by the UV lithography method. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1523–1528, 2007 [ABSTRACT FROM AUTHOR]

This paper presents the development of a novel aluminum-filled high dielectric constant composite for embedded passive applications. Aluminum is well known as a low-cost and fast self-passivation metal. The self-passivation forms a nanoscale insulating boundary outside of the metallic spheres, which has dramatic effects on the electrical, mechanical, and chemical behaviors of the resulting composites. Influences of aluminum particle size and filler loading on the dielectric properties of composites were studied. Because of the self-passivated insulating oxide layer of fine aluminum spheres, a high loading level of aluminum can be used while the composite materials continues to be insulating. Dielectric property measurement demonstrated that, for composites containing 80 wt % 3.0 μm aluminum, a dielectric constant of 109 and a low dissipation factor of about 0.02 can be achieved. The dielectric constant of epoxy-aluminum composites increased almost 30 times as compared with that of the pure epoxy matrix, which is about 3.5. Die shear tests showed that at such loading level, materials still had good processability and good adhesion toward the substrate. Bulk resistivity measurement, high-resolution transmission electron microscope (HRTEM) observation, and thermogravimetric analysis (TGA) were conducted to characterize the aluminum powders in order to understand the dielectric behavior of aluminum-filled composites. Bimodal aluminum-filled composites were also systematically studied in order to further increase the dielectric constant. Ouchiyama-Tanaka's model was used to calculate the theoretical maximum packing fraction (MPF) of bimodal systems. Based on the calculation, rheology studies were performed to find the optimum bimodal filler volume fraction ratio that led to the best packing efficiency of bimodal fillers. It was found that the viscosity of polymer composites showed a minimum at optimum bimodal filler volume fraction ratio. A high dielectric constant of 160 (@10 kHz) with a low dissipation factor of less than 0.025 was achieved with the optimized bimodal aluminum composites. The developed aluminum composite is a promising candidate material for embedded capacitor applications. [ABSTRACT FROM AUTHOR]

The remarkable properties of carbon nanotubes (CNTs) make them attractive for microelectronic applications, especially for interconnects and nanoscale devices. In this paper, we report an efficient process to grow well-aligned CNT films and high-aspect-ratio CNT arrays with very high area distribution density (>1600 µm-2). Chemical vapor deposition (CVD) was invoked to deposit highly aligned CNTs on Al2O3/Fe coated silicon substrates of several square centimeter area using ethylene as the carbon source, and argon and hydrogen as carrier gases. The nanotubes grew at a high rate of ∼100 µm/min. for nanotube films at 800°C, while the nanotube arrays grew at ∼140 µm/min. even at 750°C, due to the base growth mode. The CNTs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and x-ray photoelectron spectroscopy (XPS). The results demonstrated that the CNTs are of high purity and form densely aligned arrays with controllable size and height. The as-grown CNT structures have considerable potential for thermal management and electrical interconnects for microelectronic devices. [ABSTRACT FROM AUTHOR]

A novel lead-free interconnect technique using variable frequency microwave (VFM) was investigated. The lead-free solder interconnection between the component chips and the metal pads through VFM was first demonstrated. Comparison between the microstructures of the lead-free solder joints on Cu and Sn surfaces formed by a conventional thermal reflow process and VFM was conducted. The VFM heating technique successfully created the lead-free solder/Cu and Sn joints through their intermetallic compounds (IMCs), while maintaining the substrate temperature as low as 210°C. [ABSTRACT FROM AUTHOR]

In this letter, we report a modified percolative polymer composite that has a low dielectric loss (tan δ∼0.02@10 KHz, comparable to that of the polymer matrix), a high dielectric constant (k>100@10 KHz, about 30 times higher than that of the polymer matrix), and a low frequency dependence. This high-k polymer hybrid is filled with self-passivated micro- and nano-aluminum particles. The self-passivation of an aluminum particle results in dense nanoscale insulating Al2O3 shells outside of the metallic spheres, which allows the electrons in the metallic core to tunnel through it, and thereby the aluminum/polymer composites exhibit a high dielectric constant as a percolation system; on the other hand, the insulating oxide layer restricts the electron transfer between aluminum particles, thus leading to a very low loss of the composites. [ABSTRACT FROM AUTHOR]

A series of Au-loaded porous g-C3N4 nanosheets were prepared by anchoring Au nanoparticles onto g-C3N4 surfaces. The as-prepared samples were characterized via x-ray powder diffraction, Fourier transform infrared, transmission electron microscopy, Brunauer–Emmett–Teller, photoluminescence, and ultraviolet–visible measurements, respectively. The activities of Au/g-C3N4 composites were evaluated by the photocatalytic degradation of gaseous isopropyl (IPA) under visible-light illumination. The results indicated that 2% Au/g-C3N4 exhibited the highest photocatalytic efficiency of gaseous IPA oxidation (11.51 ppm min−1), which was 2.4 times higher than that of pure g-C3N4 nanosheets. The remarkable improved photodegradation efficiency derived from the promoted photoinduced carriers separation and larger specific surface area. For one thing, the ultrathin mesoporous g-C3N4 nanosheets provided abundant reactive sites and facilitated electron diffusion. For another, the localized surface plasmon resonance and electron–sink effect of Au particles significantly suppress the recombination of the photoinduced holes and electrons. Therefore, the deposition of Au nanoparticles with porous g-C3N4 nanosheets could be regarded as an efficient way to enhance the photocatalytic activity of gaseous IPA pollutant removal. [ABSTRACT FROM AUTHOR]

A novel method was developed for synthesizing SnO2 zigzag nanobelts on a silicon substrate with the assistance of CuO powder. The crystalline structure and morphology of SnO2 zigzag nanobelts were characterized using x-ray diffraction, scanning electron microscopy and transmission electron microscopy. The growth habits and formation mechanism of the obtained SnO2 zigzag nanobelts were discussed in detail based on a series of experimental results. The optical property was evaluated by room temperature photoluminescence spectra. Field emission properties of SnO2 zigzag nanobelts was measured for the first time leading to good performance with a turn-on field of 1.9 V µm[?]1 and a threshold field of 5.1 V µm[?]1. [ABSTRACT FROM AUTHOR]

Polymer-ceramic nanocomposites are the major candidate dielectrics for embedded capacitors. Due to the poor adhesion and poor thermal stress reliability at high filler loadings, commercially available polymer-ceramic composites can only achieve a maximum dielectric constant of ∼30. However, a high dielectric constant of ∼50-200 is required to make the layout area small enough for embedding applications. In this work, we systematically studied the material formulations in order to obtain a high dielectric constant (κ > 50) at the lowest ceramic filler loading. It was found that material design and processing were critical. By modifying the epoxy matrix with a chelating agent and using bimodal fillers and a proper amount of dispersing agent, dielectric constants >50 were obtained at moderate filler loadings. [ABSTRACT FROM AUTHOR]

High dielectric constant (high-k) polymer composites are of great interest for embedded capacitor applications. Previously, we demonstrated that epoxy- aluminum composites are promising for embedded capacitor applications, because they have a high dielectric constant and a low dielectric loss due to the core-shell structure of the self-passivated aluminum particles. In this work, to further understand the dielectric behavior of aluminum composites, lower-loss polymers such as silicone, polyimide, polynorbornene, and benzocyclobutene were explored as matrices for the aluminum composites. It is found that the polymer matrices can significantly change the dielectric properties of the aluminum composites. A polymer matrix with a lower dielectric constant generally results in a lower dielectric constant of its aluminum composites. In this regard, polymer-aluminum composites have a similar dielectric characteristic as polymer-ceramic composites. Thermomechanical properties of aluminum composites were characterized by a thermomechanical analyzer. [ABSTRACT FROM AUTHOR]