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The production of broadband, terawatt terahertz (THz) pulses has been demonstrated by irradiating relativistic lasers on solid targets. However, the generation of extremely powerful, narrow-band and frequency-tunable THz pulses remains a challenge. Here, we present a novel approach for such THz pulses, in which a plasma wiggler is elaborated by a table-top laser and a near-critical density plasma. In such a wiggler, the laser-accelerated electrons emit THz radiations with a period closely related to the plasma thickness. The theoretical model and numerical simulations predict that a THz pulse with a laser--THz energy conversion of over 2.0%, an ultra-strong field exceeding 80 GV/m, a divergence angle of approximately 20° and a center frequency tunable from 4.4 to 1.5 THz can be generated from a laser of 430 mJ. Furthermore, we demonstrate that this method can work across a wide range of laser and plasma parameters, offering potential for future applications with extremely powerful THz pulses. [ABSTRACT FROM AUTHOR]

Hepatic ischemia/reperfusion (I/R) injury is an inflammation-mediated process arising from ischemia/reperfusion-elicited stress in multiple cell types, causing liver damage during surgical procedures and often resulting in liver failure. Endoplasmic reticulum (ER) stress triggers the activation of the unfolded protein response (UPR) and is implicated in tissue injuries, including hepatic I/R injury. However, the cellular mechanism that links the UPR signaling to local inflammatory responses during hepatic I/R injury remains largely obscure. Here, we report that IRE1α, a critical ER-resident transmembrane signal transducer of the UPR, plays an important role in promoting Kupffer-cell-mediated liver inflammation and hepatic I/R injury. Utilizing a mouse model in which IRE1α is specifically ablated in myeloid cells, we found that abrogation of IRE1α markedly attenuated necrosis and cell death in the liver, accompanied by reduced neutrophil infiltration and liver inflammation following hepatic I/R injury. Mechanistic investigations in mice as well as in primary Kupffer cells revealed that loss of IRE1α in Kupffer cells not only blunted the activation of the NLRP3 inflammasome and IL-1β production, but also suppressed the expression of the inducible nitric oxide synthase (iNos) and proinflammatory cytokines. Moreover, pharmacological inhibition of IRE1α's RNase activity was able to attenuate inflammasome activation and iNos expression in Kupffer cells, leading to alleviation of hepatic I/R injury. Collectively, these results demonstrate that Kupffer cell IRE1α mediates local inflammatory damage during hepatic I/R injury. Our findings suggest that IRE1α RNase activity may serve as a promising target for therapeutic treatment of ischemia/reperfusion-associated liver inflammation and dysfunction. [ABSTRACT FROM AUTHOR]

The beam-column node is an important component of structures and is vital to structural safety. However, existing standards lack design formulas and structural requirements of the Precast Prestressed Efficiently Fabricated Frame (PPEFF) nodes. To investigate mechanical properties of PPEFF nodes deeply, a low-cycle reciprocating load test was conducted on five PPEFF side-node species Factors such as the failure mode, hysteretic skeleton curve, and ductility of PPEFF nodes were analysed to study their influences on the mechanical properties of the nodes. A previous calculation formula of unbounded prestressed tendon stress growth was modified according to the results of the low-cycle reciprocating load test. Results demonstrate that the hysteretic curves of PPEFF nodes are generally full, and the bearing capacity of the nodes increases significantly with the rise of the reinforcement ratio of unprestressed tendon and initial prestress. However, the energy consumption performance of the nodes declines when the initial prestress is too high. During the modification of the previous calculation formula, it is discovered that when the reduction factor of positive loading (k1) is 0.28 and the reduction factor of negative loading (k2) is 0.13, calculation values of the formula agree well with measured values. The obtained conclusions provide a significant reference for the design formula of PPEFF nodes. [ABSTRACT FROM AUTHOR]

A review of 16 species of Hesperosoma Scheerpeltz from China is presented. Five new species are described: H. (s.str.) chenchangchini sp. nov. from Yunnan, H. (s.str.) languidum sp. nov. from Yunnan, H. (s.str.) motuoense sp. nov. from Xizang, H. (Paramichrotus) parvioculatum sp. nov. from Hubei, Hunan and H. (s.str.) xizangense sp. nov. from Xizang. Two species are new to China: H. (Paramichrotus) brunkei Schillhammer, 2015 from Yunnan and H. (s.str.) kleebergi Schillhammer, 2009 from Xizang. Females of H. (Paramichrotus) alexpuchneri Schillhammer, 2009, H. (Paramichrotus) guizhouense Schillhammer, 2018 and H. (s.str.) flavoterminale Schillhammer, 2004 are described for the first time. Habitus and diagnostic characters of all species are photographed and a key to Chinese species of Hesperosoma is provided. [ABSTRACT FROM AUTHOR]

PURPOSE: To describe the supportive care needs of Chinese women newly diagnosed with breast cancer prior to adjuvant chemotherapy. PARTICIPANTS & SETTING: 13 women newly diagnosed with breast cancer were recruited from a public teaching hospital in northern China. METHODOLOGIC APPROACH: Semistructured interviews were conducted, and data were analyzed following a qualitative descriptive approach and qualitative content analysis. FINDINGS: The following five themes emerged: (a) physical symptoms management; (b) complex psychological pressure related to chemotherapy, family, and the missing breast; (c) hope of acquiring chemotherapy-related information in advance; (d) daily life guidance; and (e) communication and surrounding support. [ABSTRACT FROM AUTHOR]

Genetic resources are important strategic resources for the national interest, security, and sustainable economic and social development of a country. Wild germplasm with their great potential in bio-industry applications, received wide attention globally, specifically in wild plant preservation. China has achieved great progress in the infrastructure building and preservation of wild germplasm. This study suggests that it is crucial to develop China's national strategy of wild germplasm preservation by improving the top-down design and overall planning, other suggestions include enhancing the survey and collection projects of wild species and the evaluation of germplasm traits; enforcing and implementing laws and regulations on biological resources protection; promoting cooperation and joint work plans on germplasm management and regulation enforcement; talent and team building to strengthen the germplasm facilities management and operation; increasing the input on fundamental research and the development of technical standards, and arising the public awareness on germplasm conservation through training programmes. [ABSTRACT FROM AUTHOR]

Ceropegia jinshaensis D.T.Liu & Z.K.Wu (Asclepiadoideae, Apocynaceae), a new species from northwestern Yunnan along the upper Yangtze river of China, is described and illustrated. This species is similar to C. meleagris H. Huber, C. dorjei C. E. C. Fischer and C. aridicola W. W. Smith, but can be distinguished easily by its leaf shape and floral features, especially the corolla shape and size, the interior of corolla tube and coronal characters. [ABSTRACT FROM AUTHOR]

The cytoplasmic coat protein complex-II (COPII) is evolutionarily conserved machinery that is essential for efficient trafficking of protein and lipid cargos. How the COPII machinery is regulated to meet the metabolic demand in response to alterations of the nutritional state remains largely unexplored, however. Here, we show that dynamic changes of COPII vesicle trafficking parallel the activation of transcription factor X-box binding protein 1 (XBP1s), a critical transcription factor in handling cellular endoplasmic reticulum (ER) stress in both live cells and mouse livers upon physiological fluctuations of nutrient availability. Using live-cell imaging approaches, we demonstrate that XBP1s is sufficient to promote COPII-dependent trafficking, mediating the nutrient stimulatory effects. Chromatin immunoprecipitation (ChIP) coupled with high-throughput DNA sequencing (ChIP-seq) and RNA-sequencing analyses reveal that nutritional signals induce dynamic XBP1s occupancy of promoters of COPII traffic-related genes, thereby driving the COPII-mediated trafficking process. Liver-specific disruption of the inositol-requiring enzyme 1α (IRE1α)-XBP1s signaling branch results in diminished COPII vesicle trafficking. Reactivation of XBP1s in mice lacking hepatic IRE1α restores COPII-mediated lipoprotein secretion and reverses the fatty liver and hypolipidemia phenotypes. Thus, our results demonstrate a previously unappreciated mechanism in the metabolic control of liver protein and lipid trafficking: The IRE1α-XBP1s axis functions as a nutrient-sensing regulatory nexus that integrates nutritional states and the COPII vesicle trafficking. [ABSTRACT FROM AUTHOR]

The ultimate strength of metallic pipelines will be inevitably affected when they have suffered from structural damage after mechanical interference. The present experiments aim to investigate the residual ultimate bending strength of metallic pipes with structural damage based on large-scale pipe tests. Artificial damage, such as a dent, metal loss, a crack, and combinations thereof, is introduced to the pipe surface in advance. Four-point bending tests are performed to investigate the structural behavior of metallic pipes in terms of bending moment-curvature diagrams, failure modes, bending capacity, and critical bending curvatures. Test results show that the occurrence of structural damage on the pipe compression side reduces the bending capacity significantly. Only a slight effect has been observed for pipes with damage on the tensile side as long as no fracture failure appears. The possible causes that have introduced experimental errors are presented and discussed. The test data obtained in this paper can be used to further quantify damage effects on bending capacity of seamless pipes with similar D/t ratios. The comparison results in this paper can facilitate the structural integrity design as well as the maintenance of damaged pipes when mechanical interference happens during the service life of pipelines. [ABSTRACT FROM AUTHOR]

Two genera, Callipeltis Steven (Rubiaceae) and Acanthocephalus Kar. & Kir. (Asteraceae), together with five species, Callipeltis cucullaris (L.) DC., Acanthocephalus benthamianus Regel, Galium verticillatum Danthoine ex Lam. (Rubiaceae), Nonea turcomanica Popov (Boraginaceae), and Erysimum croceum Popov (Brassicaceae), are reported as new records to China. [ABSTRACT FROM AUTHOR]

Based on morphological studies performed on live plants in the field and specimens deposited in herbaria, a new species, Glochidion shanense Gang Yao & Shixiao Luo (Phyllantheae, Phyllanthaceae), is here described and illustrated. The species is morphologically most similar to G. ellipticum Wight, but can be distinguished from the latter by having hairy branchlets, longer pedicels, uniseriate and narrowly triangular sepals of female flowers, 4-5-locular ovaries, stout and cylindric persistent style on fruits. [ABSTRACT FROM AUTHOR]

Fluvirosaones A (1) and B (2), together with virosecurinine (3), were isolated from Flueggea virosa. Their structures were determined by physical, spectroscopic, and X-ray analysis and confirmed through comparison of the calculated and experimental 13C NMR and electronic circular dichroism (ECD) data. Compounds 1 and 2 represent the first examples of a pentacyclic Securinega alkaloid containing a pentacyclic system and an α,β-unsaturated ketone. Plausible biogenetic pathways of compounds 1 and 2 are proposed. [ABSTRACT FROM AUTHOR]

Southern yellow pine (Pinus sp.) wood cubes were vacuum-pressure treated with nano-SiO2 solution and different concentrations of amine copper quaternary (ACQ)/wax (0.5%, 2.5%, and 5.0% wax)-modified solutions. The effects of wax concentration and nano-SiO2 addition on water absorption, air drying shrinkage, and moisture swelling stabilities were investigated. The results showed that during the whole process of water absorption and air drying shrinkage, better stability of nano-SiO2 modified ACQ-treated wood could only be obtained with the ratio of wax addition equal to 2.5%. However, the best moisture swelling resistance was found in the samples modified with the highest wax addition (5.0%). Both wax and nano-SiO2 could be useful for keeping the dimensional stability of the treated wood. [ABSTRACT FROM AUTHOR]

Bamboo filament, a material often used for indoor decoration, should be treated with flame retardants for safe use. This study evaluated the effects of different boron fire retardants on the heat release and smoke release of bamboo filaments and untreated samples via a cone analysis. A thermogravimetric analyzer (TA) instrument was used to investigate the fire retardant mechanisms of the different boron compounds. The results showed that compared to the untreated samples, fire retardants that contained boric acid or borax effectively reduced the heat and smoke release from the bamboo filament. The effects of the different ingredients in the fire retardant on the combustion process were quite different. During the combustion process, borax displayed better performance for restraining the heat release rate than boric acid, while for the total amount of heat release and the smoke suspension performance, the result was the converse. The excellent synergistic effect could be obtained by a mixture that contained a reasonable proportion of boric acid and borax (Boric Acid:Borax = 1:1). In the pyrolysis process, boric acid had stronger catalytic dehydration, while the mass loss in the treated samples with boric acid or higher proportions of boric acid was less than the loss in the boraxtreated samples. [ABSTRACT FROM AUTHOR]

This study aims to develop a second order self-organizing fuzzy neural network (SOFNN) to predict the hourly concentrations of fine particulate matter (PM2.5) for the next 24 h at a regional background station called Shangdianzi (SDZ) in China from 14 to 23 January 2010. The structure of the SOFNN was automatically adjusted according to the sensitivity analysis (SA) of model output and the parameter-learning phase was performed applying a second order gradient (SOG) algorithm. Principal component analysis (PCA) was employed to select the dominating factors for PM2.5 concentrations as the input variables for the SOFNN. It was found that the dominating variables (relative humidity (RH), pressure (Pre), aerosol optical depth (AOD), wind speed (WS) and wind direction (WD)) extracted by PCA agreed well with the characteristics of PM2.5 at SDZ where the PM2.5 concentrations were heavily affected by meteorological parameters and were closely related to AOD. The forecasting results showed that the proposed SOG-SASOFNN performed better than other models with higher coefficient of determination (R2) during both training phase and test phase (0.89 and 0.84, respectively) in predicting PM2.5 concentrations at SDZ. In conclusion, the developed SOG-SASOFNN provided satisfying results for modeling the hourly distribution of PM2.5 at SDZ during the studied period. [ABSTRACT FROM AUTHOR]

Orientation is pivotal in circulating fluidized beds using cylinder-shaped particles. This study developed a three-dimensional multiway coupling model for predicting the orientation of cylindrical particles in circulating fluidized beds. The coupling algorithm between motorial cylindrical particles and the turbulence was established by incorporating the correlation between Lagrangian time scales and the k-ε model. Collisions among cylindrical particles were solved by combining rigid body impact dynamics with the hard sphere model. The results showed that the majority of cylindrical particles are prone to align with the streamline, which is in good agreement with the experimental observation. Cylindrical particles become more oriented along rising height position in the riser, increasing the slenderness ratio and decreasing the distance to the wall. Under turbulence conditions, the effect of Reynolds number on the orientation of cylindrical particles was found to be marginal. [ABSTRACT FROM AUTHOR]

Background: Habitat fragmentation and the resulting decline in population size and density commonly reduce the reproduction of rare and threatened species. We investigated the impacts of population size and density on reproduction in more than 30 populations of Circaeaster agristis, a narrow endemic and threatened species, in 2010 and 2011. We also examined the effects of NND (nearest neighbor distance) and LNS (local neighbor size), within radii of 0.1 m, 0.2 m and 0.3 m, on reproduction in two of the populations in 2011. Results: Population size did not affect fruit (seed) number and fruit set in either year studied. Population density had an indirect negative effect on fruit number and fruit set as a consequence of a negative effect on plant size in 2010, but had no effect on fruit number and fruit set in 2011. Within populations, individual fruit number did not change, and individual fruit set increased independent of plant size, in response to increasing NND. Both individual fruit number and individual fruit set increased, independent of plant size, with increases in LNS within a 0.1 m radius, but did not change with increases in LNS within radii of between 0.1 m and 0.2 m radii or between 0.2 m and 0.3 m. Conclusions: The effect of habitat fragmentation on reproduction of C. agristis is scale-dependent. In contrast to the generally accepted idea that fragmentation reduces plant reproduction, reproductive success may increase in sparse populations or increase in response to decreases in LNS in C. agristis. [ABSTRACT FROM AUTHOR]

Activating rearranged during transfection (RET) mutations function as the initiating causative mutation for multiple endocrine neoplasia type 2A (MEN2A). However, no conclusive findings regarding the non-RET genetic events have been reported. This is the first study, to our knowledge, examining genomic alterations in matched MEN2A-associated tumors. We performed exome sequencing and SNP array analysis of matched MEN2A tumors and germline DNA. Somatic alterations were validated in an independent set of patients using Sanger sequencing. Genes of functional interest were further evaluated. The germline RET mutation was found in all MEN2A-component tumors. Thirty-two somatic mutations were identified in the nineMEN2A-associated tumors, of which 28(87.5%) were point mutations and 4 (12.5%) were small insertions, duplications, or deletions. We sequenced all the mutations as well as coding sequence regions of the 12 genes in an independent sample set including 35 medullary thyroid cancers (20 MEN2A) and 34 PCCs (22 MEN2A), but found no recurrent mutations. Recurrent alterations were found in 13 genes with either mutations or alterations in copy number, including an EIF4G1 mutation (p. E1147V). Mutation of EIF4G1 led to increased cell proliferation and RET/MAPK phosphorylation, while knockdown of EIF4G1 led to reduced cell proliferation and RET/MAPK phosphorylation in TT, MZ-CRC1, and PC-12 cells. W e found fewer somatic mutations in endocrine tumors compared with non-endocrine tumors. RET was the primary driver in MEN2A-associated tumors. However, low-frequency alterations such as EIF4G1 might participate in MEN2A-associated tumorigenesis, possibly by regulating the activity of the RET pathway. [ABSTRACT FROM AUTHOR]

To explore a new approach for osteoporosis recognition with images, a texture analysis was made of 27 bone tissue images (16 of which from a SHAM group, and 11 from an OVX group). Texture features were then extracted through a co-occurrence matrix and a run-length matrix, and the texture features with significant differences between the two groups were chosen and used as the features in the classification course based on a Support Vector Machine (SVM). The results show that there are obvious statistic differences between the SHAM group and the OVX group in terms of texture features. Furthermore, the highest recognition accuracy was achieved at 92.59%. A SVM based on a linear function showed the highest accuracy rate and the lowest error rate in recognition. This new approach can be used to recognize osteoporosis effectively and thus can provide a valuable reference to the clinical application in osteoporosis diagnosis with medical images. [ABSTRACT FROM AUTHOR]

Thermal sprayed YSZ coatings subjected to high-current pulsed electron beam (HCPEB) with different pulses were investigated. The microstructure evolution, surface roughness and phase transformation of the coatings were characterized by means of a scanning electron microscope (SEM), a three-dimensional laser scanning microscope (LSM) and X-ray diffraction (XRD), respectively. Under HCPEB irradiation, the coarse surface was melted and a flat and compact surface with a continuous micro-crack network was formed. At the same time, rapid thermal cycles during HCPEB irradiation led to the very fine grains formed on the surface and the fully dense columnar grains in the fracture cross-section. When using 10 or 20 pulses, wavy morphology and vapor deposition were induced due to the evaporation effect. The phase composition in irradiated coatings mainly consisted of a non-equilibrium t'-phase, the same as the as-sprayed phase composition. After HCPEB irradiation with 10 or 20 pulses, the residual m-phase was mostly eliminated owing to the homogenization of composition during the HCPEB irradiated process. High temperature oxidation test indicates that the irradiated coating with 10 pulses has a much higher oxidation resistance. [ABSTRACT FROM AUTHOR]

We propose a thin metallic film perforated with a hexagonal periodic array of cubic holes and calculate its optical properties through the three-dimensional finite-difference time-domain method. Perfect superbroadband optical transparency from visible to near-infrared is achieved with the transmittance up to 99% due to the excitation of surface plasmon polaritons on the nanopatterned metal surface, localized surface plasmons at the edges of the cubic holes, and their cooperative interaction. The perfect superbroadband optical transparency of the proposed structure mainly depends on the size of holes and the period of the cubic hole array, and the proposed structure with perfect superbroadband optical transparency can resist to the interference of surrounding dielectric environment, which would provide fascinating potential applications in absorbers, solar cells, and transparent electrodes. [ABSTRACT FROM AUTHOR]

Novel nanoporous silica aerogel impregnated highly porous zirconia ceramics were successfully synthesized from silica gel and camphene-based freeze-cast porous zirconia ceramics. The resultant porous ceramic–aerogel composites exhibited high compressive strength of 36.8MPa, and ultra-low thermal conductivity ranging from 0.041 to 0.098Wm−1 K−1, as the porosity increased from 46.5% to 69.8%. The present work provides an efficient way to fabricate high-strength thermal insulation materials with ultra-low thermal conductivity. [ABSTRACT FROM AUTHOR]

Abstract: This paper conducts thermal shock case studies for three typical thermal shock specimens that are important in thermal shock tests: a ceramic layer under a hot shock, a ceramic layer under a cold shock and a ceramic coating under a cold shock. All material properties are assumed to be functions of temperature. The temperature field without cracking is obtained by using the finite element/finite difference method. Time-varied thermal stress intensity factors are obtained by using the weight function method for various parameters of the problem. The thermal shock resistance curves are obtained and the critical size parameters, which control the applicability of the stress-based criterion and the fracture-mechanics-based criterion for the determination of the thermal shock resistance of ceramics, are explored. The studies demonstrate the significance of incorporating temperature-dependent material properties on the thermal shock resistance of ceramic materials for high-temperature applications. The dominant property change responsible for the improvement is the significant reduction in Young’s modulus with increasing temperature. As a result, the thermal stress level is reduced considerably and the thermal shock resistance of the ceramic material is improved greatly. [ABSTRACT FROM AUTHOR]

The recent discovery of induced pluripotent stem cell (iPSC) technology provides an invaluable tool for creating in vitro representations of human genetic conditions. This is particularly relevant for those diseases that lack adequate animal models or where the species comparison is difficult, e.g. imprinting diseases such as the neurogenetic disorder Prader-Willi syndrome (PWS). However, recent reports have unveiled transcriptional and functional differences between iPSCs and embryonic stem cells that in cases are attributable to imprinting errors. This has suggested that human iPSCs may not be useful to model genetic imprinting diseases. Here, we describe the generation of iPSCs from a patient with PWS bearing a partial translocation of the paternally expressed chromosome 15q11-q13 region to chromosome 4. The resulting iPSCs match all standard criteria of bona fide reprogramming and could be readily differentiated into tissues derived from the three germ layers, including neurons. Moreover, these iPSCs retain a high level of DNA methylation in the imprinting center of the maternal allele and show concomitant reduced expression of the disease-associated small nucleolar RNA HBII-85/SNORD116. These results indicate that iPSCs may be a useful tool to study PWS and perhaps other genetic imprinting diseases as well. [ABSTRACT FROM AUTHOR]

Abstract: Sapphire single crystals grown by an improved Kyropoulos-like method are irradiated by fast neutron flux. The irradiated doses of neutron are 1018 and 1019 n/cm2. The infrared transmission spectra of sapphire were studied before and after irradiation. The irradiated samples were annealed at 200, 400, 600, 800 and 1000°C for 10min in ambient atmosphere. Positron annihilation studies have been carried out before and after neutron irradiation. The experimentally measured positron lifetime in the pristine specimen is 143ps. There were aluminum vacancies produced in sapphire crystals after neutron irradiation. The positron lifetime increased with the dose of neutron flux. A longer value τ 2 was found after annealing at 600°C, which indicated vacancies were aggregated with each other. The second long-time component τ 2 has been found to increase with the annealing temperature. There was almost no change in peak position of the CDB spectra after neutron irradiation and isothermal annealing. The chemical environment of core in sapphire did not change greatly after neutron irradiation. [Copyright &y& Elsevier]

To better understand the characteristics of ambient abundance of volatile organic compounds (VOCs) in Shanghai, one of the biggest metropolis of China, VOCs were measured with a gas chromatography system equipped with a mass-selective detector (GC/MSD) from July 2006 to February 2010. An intensive measurement campaign was conducted (eight samples per day with a 3 hour interval) during May 2009. The comparison of ambient VOCs collected in different regions of Shanghai shows that the concentrations are slightly higher in the busy commercial area (28.9 ppbv at Xujiaui) than in the urban administrative area (24.3 ppbv at Pudong). However, during the intensive measurement period, the concentrations in the large steel industrial area (28.7 ppbv at Baoshan) were much higher than in the urban administrative area (18 ppbv at Pudong), especially for alkanes, alkenes, and toluene. The seasonal variations of ambient VOC concentrations measured at the Xujiahui sampling site indicate that the VOC concentrations are significantly affected by meteorological conditions (such as wind direction and precipitation). In addition, although alkanes are the most abundant VOCs at the Xujiahui measurement site, the most important VOCs contributing to ozone formation potential (OFP) are aromatics, accounting for 57% of the total OFP. The diurnal variations of VOC concentrations show that VOC concentrations are higher on weekdays than in weekends at the Xujiahui sampling site, suggesting that traffic condition and human activities have important impacts on VOC emissions in Shanghai. The evidence also shows that the major sources of isoprene are mainly resulted from gasoline evaporation at a particular time (06:00-09:00) in the busy commercial area. The results gained from this study provide useful information for better understanding the characteristics of ambient VOCs and the sources of VOCs in Shanghai. [ABSTRACT FROM AUTHOR]

Cracks and porosities inside the piezoelectric materials can weaken the electromechanical coupling effect, and hence influence the electromechanical coupling behavior of piezoelectric materials considerably. This paper studies the effect of internal cracking on the effective properties of piezoelectric media. It focuses on the piezoelectric medium of finite size with finite crack. The mechanical and electric fields in the piezoelectric material and the crack are formulated by singular integral method. Effects of crack size, medium border, and electric permeability of the crack on the overall electromechanical properties of the piezoelectric material are obtained and displayed graphically. In addition, the crack tip coupling electromechanical field intensity factors are also presented as they are not available in open literature for a finite crack in a finite piezoelectric media. [ABSTRACT FROM AUTHOR]

The amplitude of nonlinear excitations in BECs with inhomogeneities is governed by a generalized variable-coefficient Korteweg-de Vries model. With symbolic computation, the Exp-function method is modified to obtain analytical nontraveling solitary-wave and periodic-wave solutions. Through the qualitative analysis and graphical illustration, the inhomogeneous propagation features of solitary waves are discussed, and some observable effects for BEC dynamic in the presence of external potentials are provided. The modified Exp-function method is also applicable to other variable-coefficient nonlinear evolution equations. [ABSTRACT FROM AUTHOR]

Abstract: The paper establishes a methodology for the study of thermal shock resistance behavior of ceramic coating/metal substrate systems, based on multiple cracking analysis. The stress criterion and the toughness criterion are used to predict the failure behavior of the system. Multi-scale analysis of the thermal shock resistance of the system is made and variations of the thermal shock resistance of the system with crack density are displayed for different values of coating to substrate thickness ratio. Some critical size parameters, which control the applicability of the stress-based criterion and the fracture mechanics-based criterion for the determination of the thermal shock resistance of the coating/substrate systems, are explored. [Copyright &y& Elsevier]

Abstract: Most magnetoelectroelastic composites were developed in the form of a composite laminate by alternating the ferromagnetic layers and ferroelectric layers during stacking. Presence of interfacial crack may influence the magneto-electro-mechanical coupling behavior of magnetoelectroelastic materials considerably. This paper describes a method to analyze the transient response of a layered magnetoelectroelastic medium of finite size with an interface crack. Based on Fourier and Laplace transforms, the boundary value problem is reduced to a system of generalized singularity integral equations in the Laplace transform domain. By utilized numerical Laplace inversion, the time-dependent full field solutions are obtained in the time domain. Effects of medium size, crack-face electric and magnetic boundary conditions on the dynamic crack tip fields are studied. By investigating an interface notch of finite gap thickness, the electric and magnetic properties of the medium inside the notch are included in the analytical model so that the applicability of crack-face electric and magnetic boundary conditions on the transient response of the magnetoelectroelastic medium can be investigated. [Copyright &y& Elsevier]

All-cellulose composite films were prepared, for the first time, from native cellulose nanowhiskers and cellulose matrix regenerated from aqueous NaOH−urea solvent system on the basis of their temperature-dependent solubility. The cellulose whiskers retained their needlelike morphology with mean length and diameter of 300 and 21 nm as well as native crystallinity when added to the latter solution at ambient temperature. The structure and physical properties of the nanocomposite films were characterized by scanning electron microscope, X-ray diffraction, and tensile tests. The composite films were isotropic and transparent to visible light and showed good mechanical properties as a result of the reinforcement by the whiskers. By varying the ratio of the cellulose whiskers to regenerated cellulose matrix (cellulose II), the tensile strength and elastic modulus of the nanocomposite films could be tuned to reach 124 MPa and 5 GPa, respectively. The tensile strength of the nanocomposite films could reach 157 MPa through a simple drawing process, with the calculated Hermans’ orientation parameter of 0.30. This work provided a novel pathway for the preparation of biodegradable all-cellulose nanocomposites, which are expected to be useful as biomaterials and food ingredients. [ABSTRACT FROM AUTHOR]

Despite considerable progress in the field of metal nanoparticles synthesis, major challenges remain in many practical applications of nanoparticles which require their immobilization on solid substrates, presenting additional difficulty in separation and processing. Here, transparent nanoporous cellulose gel obtained from aqueous alkali hydroxide-urea solution was examined as supporting medium for noble metal nanoparticles. Silver, gold, and platinum nanoparticles were synthesized in the gel by hydrothermal reduction by cellulose or by added reductant. Both methods gave nanoparticles embedded with high dispersion in cellulose gels. Supercritical CO2drying of the metal-carrying gel gave corresponding aerogels with high transmittance, porosity, surface area, moderate thermal stability, and good mechanical strength. The cellulose and metal-cellulose gels were characterized by UV/vis spectroscopy, optical microscopy, SEM, TEM, XRD, nitrogen physisorption, TGA, and tensile testing, systematically. [ABSTRACT FROM AUTHOR]

Cellulose can be dissolved in precooled (−12 °C) 7 wt % NaOH−12 wt % urea aqueous solution within 2 min. This interesting process, to our knowledge, represents the most rapid dissolution of native cellulose. The results from 13C NMR, 15N NMR, 1H NMR, FT-IR, small-angle neutron scattering (SANS), transmission electron microscopy (TEM), and wide-angle X-ray diffraction (WAXD) suggested that NaOH “hydrates” could be more easily attracted to cellulose chains through the formation of new hydrogen-bonded networks at low temperatures, while the urea hydrates could not be associated directly with cellulose. However, the urea hydrates could possibly be self-assembled at the surface of the NaOH hydrogen-bonded cellulose to form an inclusion complex (IC), leading to the dissolution of cellulose. Scattering experiments, including dynamic and static light scattering, indicated that most cellulose molecules, with limited amounts of aggregation, could exist as extended rigid chains in dilute solution. Further, the cellulose solution was relatively unstable and could be very sensitive to temperature, polymer concentration, and storage time, leading to additional aggregations. TEM images and WAXD provided experimental evidence on the formation of a wormlike cellulose IC being surrounded with urea. Therefore, we propose that the cellulose dissolution at −12 °C could arise as a result of a fast dynamic self-assembly process among solvent small molecules (NaOH, urea, and water) and the cellulose macromolecules. [ABSTRACT FROM AUTHOR]

Abstract  Fe3O4/SiO2/poly (N-isopropylacrylamide-co-N,N-dimethylaminoethyl methacrylate) [P(NIPAM-co-DMA)] multiresponsive composite microspheres with core–shell structure were synthesized by template precipitation polymerization. First, the magnetite nanoparticles were coated with silica and then modified with 3-(trimethoxysilyl)-propyl methacrylate (MPS). Subsequently, the Fe3O4/SiO2 particles grafted with MPS were used to seed the precipitation copolymerization of NIPAM and DMA. The composite microspheres with core–shell structure were superparamagnetic, pH-sensitive, and thermoresponsive. The swelling ratio (D25 �C, pH = 3/D50 �C, pH = 9)3 coupling of pH and temperature increased up to 21.2, which was much higher than that without comonomer DMA. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the fracture problem of a piezoelectric cylinder with a periodic array of embedded circular cracks. An electro-mechanical fracture mechanics model is established first. The model is further used to the thermal fracture analysis of a piezoelectric cylinder subjected to a sudden heating on its outer surface. The temperature field and the associated thermal stresses and electric displacements are obtained and are added to the crack surface to form a mixed-mode boundary value problem for the electro-mechanical coupling fracture. The stress and stress intensities are investigated for the effect of crack spacing. Strength evaluation of piezoelectric materials under the transient thermal environment is made and thermal shock resistance of the medium is given. [Copyright &y& Elsevier]

Abstract: Multiple cracking is a common phenomenon for a medium subjected to a sudden temperature change. In this paper, a multiple surface cracking analysis is carried out to investigate the thermal shock resistance behavior of functionally graded materials (FGMs). The FGM is taken to be a ceramic/metal composite with its gradation characterized by the local volume fractions of metal and ceramic phases. The finite element method is used to obtain the solution of the crack problem. The crack tip field intensity factors as well as the stress are computed as functions of the crack spacing, the normalized time, and the crack depth. Crack initiation behavior is discussed. It is found that the thermal shock resistance of the FGM is significantly enhanced by multiple cracking. That is, the thermal shock resistance is a monotonically increasing function of the crack density (crack density is the number of cracks per unit length; crack density increases with decreasing crack spacing). A single crack represents the lower bound solution for the thermal shock resistance of FGMs. It is also found that the gradation of the FGM has little influence on the crack tip thermal stress intensity factors but has a strong influence on the thermal shock resistance. Multiscale behavior of the thermal shock resistance of FGMs is discussed. Two critical size parameters, which control the applicability of the stress-based criterion and the fracture mechanics-based criterion to the determination of the thermal shock resistance of FGMs, are explored. [Copyright &y& Elsevier]

Abstract: The electro-elastic problem for a periodic array of cracks in a piezoelectric medium subjected to coupled electro-mechanical loads is investigated. The mixed boundary value problem, which is formulated directly in terms of the crack surface displacements and electrical potentials, results in a system of hyper-singular integral equations in which the unknown functions are the crack surface displacement and electric potential. Numerical results include the crack surface displacement and the stress and electric intensity factors for the entire range of possible periodic crack spacing and medium size. The central contribution of this paper is the development of an analytical model that predicts crack-spacing effect. The resulting model is validated by a 2D finite element analysis. [Copyright &y& Elsevier]

TiB2-Cu ceramic-metal composites were prepared by combustion synthesis of elemental titanium, boron, and copper ponders. The synthesized product consisted of two phases: TiB2 and copper. The addition of copper improved the strength and fracture toughness, thermal expansion coefficient, and thermal conductivity of TiB2. Thermal shock and ablation resistances of TiB2-Cu composites were studied using a plasma torch are heater. Monolithic TiB2 failed catastrophically when the plasma arc How reached the specimen surface. However, no cracks were found on the ablation surface of the TiB2-Cu ceramic-metal composites. The fractional mass loss was 4.09% for a TiB2- 40Cu composite, which was close to the traditional W/Cu alloys. Volatilization of metal binder and mechanical erosion of TiB2 were observed the be the major ablation mechanisms. An ablation process model is proposed for the TiB2-Cu composites. [ABSTRACT FROM AUTHOR]

Our previous work has proved that mechanical properties of a blending alginate with cellulose was significantly enhanced in a wet state and maintained its biodegradability. In this article, ion-exchange beads were prepared from cellulose and alginate in 6 wt% NaOH/4 wt% urea aqueous solution by using an emulsion phase separation method. The structure and morphology of the beads were characterized by scanning electron microscope (SEM) and Fourier transform infrared (FTIR) spectra, and the adsorption behaviors to Cd2+ and Cu2+ ions were measured by atomic absorption spectrometry (AAS). The effects of pH, adsorption time, ion concentration, temperature, and reusability of the beads on the adsorbed amount of Cd2+ and Cu2+ ions in aqueous solution were investigated by a batch method. The results indicated that the beads had a spherical shape, with ∼4–20 µm of diameter and relatively high ion-exchange capacity (3.81 mmol g−1). The combined action of Cd2+ and Cu2+ ions on beads generally was found to be antagonistic. The selectivity of the beads for the adsorption of Cd2+ ions was higher than that of Cu2+ ions. The adsorbed amount was given to a maximum for Cd2+ ions at pH 2.2, and for Cu2+ ions at pH 3.2. The adsorbed amount of the beads reached the values of 0.7 and 0.5 mmol g−1 for Cd2+ and Cu2+ ions, respectively. The beads could be regenerated by using 1 mol L−1 HCl aqueous solution, up to 95% recovery, and the adsorption–desorption cycles, performed over 10 times, maintained the adsorption capacity, indicating a good reusability. [ABSTRACT FROM AUTHOR]

Characterizes the nucleotide binding and nucleotide hydrolysis properties of the multidrug resistance associated protein (MRP) 1. Physiological function of MRP6; Increase in cellular resistance of MRP4 or MRP5 to antiviral nucleoside; Molecular basis in the mutation of pseudoxanthoma elasticum.

Objectives: The aim of this clinical study was to evaluate the effectiveness and advantages of the radiofrequency ablation maze procedure in the treatment of atrial fibrillation associated with rheumatic mitral valve disease. Methods: We developed one kind of modified Cox III maze procedure with the use of radiofrequency ablation in the treatment of atrial fibrillation associated with rheumatic mitral valve disease and compared the outcome of 96 patients of atrial fibrillation associated rheumatic mitral valve disease who underwent radiofrequency ablation maze procedure plus mitral valve replacement with that of 87 patients with atrial fibrillation associated rheumatic mitral valve disease who had mitral valve replacement during the same interval by the same surgeon. The patients in the two groups were similar in age, gender, preoperative New York Heart Association class and duration of preoperative atrial fibrillation. Results: No operative deaths occurred in the study group and the control group. Duration of cardiopulmonary bypass (137.63±10.82 vs. 90.95±7.65 min, P<0.01) and duration of aortic crossclamping (56.96±6.19 vs. 32.66±3.55 min, P<0.01) were prolonged in the study group. Blood loss from chest tubes was similar in the two groups (494.06±100.44 vs. 476.09±115.84 ml, P=0.263). Freedom from atrial fibrillation in the study group was 77% 3 years after the operation compared with 25% in the control group (P<0.01). Conclusions: The addition of the radiofrequency ablation maze procedure to mitral valve replacement is safe and effective in the treatment of atrial fibrillation associated with rheumatic mitral valve disease. [Copyright &y& Elsevier]

Mitreola liuyanii, a new species from Guizhou Province, China, are described and illustrated in this study. Morphologically, it is most similar to M. pingtaoi but can be distinguished from the latter in the characteristics of leaves arranged in a basal rosette or clustered at the stem or branch apex, shorter stem internodes and petioles, smaller narrowly oblanceolate leaf blades with ciliate margin, narrowly lanceolate bracts and glabrous capsules. [ABSTRACT FROM AUTHOR]

Background: The association between triglyceride glucose (TyG) index and depression is unclear. We conducted this analysis to explore whether higher TyG index is associated with a higher odd of depression. Methods: This was an observational study using data from the National Health and Nutrition Examination Survey (2005–2018), a cross-sectional and nationally representative database. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9). TyG index was calculated based on the equation as follows: ln [triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2], and participants were divided into quartiles based on TyG index. Weighted multivariable logistic regression models were used to explore the relationship between the TyG index and depression. Results: A total of 13,350 patients were included, involving 1001 (7.50%) individuals with depression. Higher TyG index is significantly associated with elevated depressive symptoms in U.S. adults. Multivariate-adjusted HRs for patients in the TyG index 4th quartile were higher for depression (OR = 1.46; 95% confidence interval (CI) 1.30, 1.64) compared with the 1st quartile of TyG index. Similar results were seen in men and women, across age groups, and baseline comorbidities. Conclusion: In this large cross-sectional study, our result suggests that population with higher TyG index are significantly more likely to have depressive symptoms in U.S. adults. [ABSTRACT FROM AUTHOR]

Five new orchid species from southwestern China's Yunnan Province and the Tibetan Autonomous Region, Neottia lihengiae, Neottia chawalongensis, Papilionanthe motuoensis, Gastrochilus lihengiae, and Gastrochilus bernhardtianus, are described and illustrated. To confirm their identities, and to resolve phylogenetic relationships, we sequenced the complete plastomes of these taxa with their congeneric species, adding new plastomes of three Neottia species, two Papilionanthe species and nine Gastrochilus species. Combined with published plastid sequences, our well-resolved phylogeny supported the alliance of N. lihengiae with the the N. grandiflora + N. pinetorum clade. Neottia chawalongensis is now sister to N. alternifolia, while P. motuoensis is closely related to P. subulata + P. teres. Conversely, phylogenetic analyses based on complete plastomes and plastid sequences showed inconsistent relationships among taxa in the genus Gastrochilus, but the two new species, G. lihengiae and G. bernhardtianus were supported by all datasets. [ABSTRACT FROM AUTHOR]

Introduction: Current literature on perioperative and oncological outcomes following radical cystectomy among different racial groups is limited, especially among Hispanics and Asians. The objective of this study was to assess the impact of racial differences on perioperative and oncological outcomes in a large cohort of bladder cancer patients who underwent radical cystectomy. Methods: We retrospectively reviewed the records of 3293 patients who underwent radical cystectomy with curative intent at our institution between 1971 and 2017. Based on race, patients were categorized as Hispanic (n=190), Asian (n=145), African Americans (n=67), and Caucasian (n=2891). Baseline characteristics, pericystectomy complications, and oncological outcomes, including recurrence-free and overall survival, were compared between the racial groups. Results: Mean patient age was 68±10.6 years. Median followup was 10.28 years. Body masss index and American Society of Anesthesiologists scores were significantly higher in Hispanic and African American population, and smoking incidence was lower in Asian patients. Hispanics presented with significantly higher clinical stage and longer time interval from diagnosis to treatment (mean 85.5 vs. 75.4 days in Caucasians, p<0.001). Overall 90-day complication and readmission rates were higher in Hispanics (41.06% and 18.95%, respectively). Oncological outcomes, however, were comparable between different race groups. In multivariate analysis, pathological nodal status and lymphovascular invasion were independent predictors of oncological outcomes, but race was not. Conclusions: In this very large, ethnically diverse patient cohort who underwent radical cystectomy with curative intent, pericystectomy complications were more common in Hispanics; however, race was not an independent predictor of long-term oncological outcome. [ABSTRACT FROM AUTHOR]

Biomedical researchers have been attempting to construct a wound dressing with the structure and function of a bionic natural extracellular matrix. This dressing would provide a comfortable environment for wound self-healing. In this study, cellulose-collagen fibrous networks were easily fabricated via the one-pot method using genipin in situ crosslinking collagen hydrolysate in cellulose nanofibrous membranes made by electrospinning cellulose acetate and subsequent deacetylation. The morphology, properties, and successful entrapment of collagen in the cellulose fibrous dressings were validated by scanning electron microscopy, element analysis, Fourier transform infrared spectroscopy, X-ray diffraction, water-swelling test, and thermal gravimetric analysis. The functional cellulose nanofiber-based composite membranes exhibited a network structure, good thermal stability, and acceptable water resistance. Human epidermal cells seeded on the composite nanofibrous membranes presented favorable growth, indicating good cytocompatibility and suitability of the dressing to the wound. Therefore, these novel cellulose-collagen fibrous networks may have potential use in biomedical applications. [ABSTRACT FROM AUTHOR]

Mitreola viridiflora, a new endemic species from southern Yunnan, China, is described and illustrated. It is morphologically similar to M. crystallina, M. pedicellata and M. reticulata, but can be distinguished from them by its urceolate yellow-green corolla, ovate-triangular corolla lobes, stamens inserted near middle of corolla tube, style much longer than ovary. [ABSTRACT FROM AUTHOR]

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with highly heritable heterogeneity. Mutations of CUB and sushi multiple domains 3 (CSMD3) gene have been reported in individuals with ASD. However, the underlying mechanisms of CSMD3 for the onset of ASD remain unexplored. Here, using male CSMD3 knock-out (CSMD32/2) mice, we found that genetic deletion of CSMD3 produced core autistic-like symptoms (social interaction deficits, restricted interests, and repetitive and stereotyped behaviors) and motor dysfunction in mice, indicating that the CSMD3 gene can be considered as a candidate for ASD. Moreover, we discovered that the ablation of CSMD3 in mice led to abnormal cerebellar Purkinje cell (PC) morphology in Crus I/II lobules, including aberrant developmental dendritogenesis and spinogenesis of PCs. Furthermore, combining in vivo fiber photometry calcium imaging and ex vivo electrophysiological recordings, we showed that the CSMD32/2 mice exhibited an increased neuronal activity (calcium fluorescence signals) in PCs of Crus I/II lobules in response to movement activity, as well as an enhanced intrinsic excitability of PCs and an increase of excitatory rather than inhibitory synaptic input to the PCs, and an impaired long-term depression at the parallel fiber-PC synapse. These results suggest that CSMD3 plays an important role in the development of cerebellar PCs. Loss of CSMD3 causes abnormal PC morphology and dysfunction in the cerebellum, which may underlie the pathogenesis of motor deficits and core autistic-like symptoms in CSMD32/2 mice. Our findings provide novel insight into the pathophysiological mechanisms by which CSMD3 mutations cause impairments in cerebellar function that may contribute to ASD. [ABSTRACT FROM AUTHOR]

This study aimed to develop a facile synthesis process of porous starch wall materials from purple sweet potato (PSP) for microencapsulation via enzymatic treatment. The optimum extraction conditions of purple sweet potato starch (PSP-S) were first attained by an orthogonal experiment. Response surface methodology was performed through the enzymatic hydrolysis of PSP-S using an α-amylase and glucoamylase complex to optimize the process parameters for the production of porous starch. Optimal reaction conditions were: the mass ratio (w/w) of glucoamylase to α-amylase of 6.39, amount of substrate of 19.5 g, and amount of enzymes of 0.53%. The surface morphology, microstructure, and thermal stability of the obtained samples were characterized with scanning electron microscopy, Fourier-transform infrared, and thermogravimetric analyses, respectively. The purple sweet potato porous starch (PSP-PS) had a stable oil adsorption capacity, and the molecular structure and thermal stability of porous starch were not substantially different from those of native starch. This study offers a simple yet efficient approach to produce fully biodegradable food-based porous materials for potential applications in oil microencapsulation. [ABSTRACT FROM AUTHOR]