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Background Spray cut chrysanthemum is a vital flower with high ornamental value and popularity in the world. However, the excessive quantity of pollen dispersal of most spray cut chrysanthemum is an adverse factor during its flowering stage, and can significantly reduce its ornamental value and quickly shorten its vase life. More seriously, excessive pollen grains in the air are usually harmful to people, especially for those with pollen allergies. Therefore, in order to obtain some valuable information for developing spray cut chrysanthemum with lessdispersed or non-dispersed pollen in the future breeding programs, we here investigated the factors affecting quantity of pollen dispersal of spray cut chrysanthemum with four cultivars, i.e. 'Qx-097', 'Noa', 'Qx-115', and 'Kingfisher', that have different quantity of pollen dispersal. Results 'Qx-097' with high quantity of pollen dispersal has 819 pollen grains per anther, 196.4 disk florets per inflorescence and over 800,000 pollen grains per inflorescence. The corresponding data for 'Noa' with low quantity of pollen dispersal are 406, 175.4 and over 350,000, respectively; and 219, 144.2 and nearly 160,000 for 'Qx-115' without pollen dispersal, respectively. 'Kingfisher' without pollen dispersal has 202.8 disk florets per inflorescence, but its anther has no pollen grains. In addition, 'Qx-097' has a very high degree of anther cracking that nearly causes a complete dispersal of pollen grains from its anthers. 'Noa' has a moderate degree of anther cracking, and pollen grains in its anthers are not completely dispersed. However, the anthers of 'Qx-115' and 'Kingfisher' do not crack at all. Furthermore, microsporogenesis and pollen development are normal in 'Qx-097', whereas many microspores or pollen degenerate in 'Noa', most of them abort in 'Qx-115', and all of them degrade in 'Kingfisher'. Conclusions These results suggest that quantity of pollen dispersal in spray cut chrysanthemum are mainly determined by pollen quantity per anther, and capacity of pollen dispersal. Abnormality during microsporogenesis and pollen development significantly affects pollen quantity per anther. Capacity of pollen dispersal is closely related to the degree of anther dehiscence. The entire degeneration of microspore or pollen, or the complete failure of anther dehiscence can cause the complete failure of pollen dispersal. [ABSTRACT FROM AUTHOR]

It is difficult to tune the magnetic properties of oxide diluted magnetic semiconductors because of the origin of ferromagnetism (FM) under different versions. Using first-principles band-structure calculations, we find that the surface oxygen dangling bonds and Indium vacancy may be responsible for the unexpected ferromagnetism in undoped In2O3 quantum dots (QDs). The surface oxygen dangling bonds produce a magnetic moment of 6 μB, which primarily distribute on the surface oxygen atoms and an Indium vacancy (VIn) produce a magnetic moment of 3 μB, which primarily distribute on the six nearest neighbors of the vacancy center. The origin of the collective magnetic moments are the holes which introduced by the surface oxygen dangling bonds and Indium vacancy. [ABSTRACT FROM AUTHOR]

Plant-plant interference is the combined effect of allelopathy, resource competition, and many other factors. Separating allelopathy from resource competition is almost impossible in natural systems but it is important to evaluate the relative contribution of each of the two mechanisms on plant interference. Research on allelopathy in natural and cultivated plant communities has been hindered in the absence of a reliable method that can separate allelopathic effect from resource competition. In this paper, the interactions between allelopathic rice accession PI312777, non-allelopathic rice accession Lemont and barnyardgrass were explored respectively by using a target (rice)-neighbor (barnyardgrass) mixed-culture in hydroponic system. The relative competitive intensity (RCI), the relative neighbor effect (RNE) and the competitive ratio (CR) were used to quantify the intensity of competition between each of the two different potentially allelopathic rice accessions and barnyardgrass. Use of hydroponic culture system enabled us to exclude any uncontrolled factors that might operate in the soil and we were able to separate allelopathy from resource competition between each rice accession and barnyardgrass. The RCI and RNE values showed that the plant-plant interaction was positive (facilitation) for PI312777 but that was negative (competition) for Lemont and barnyardgrass in rice/barnyardgrass mixed-cultures. The CR values showed that one PI312777 plant was more competitive than 2 barnyardgrass plants. The allelopathic effects of PI312777 were much more intense than the resource competition in rice/barnyardgrass mixed cultures. The reverse was true for Lemont. These results demonstrate that the allelopathic effect of PI312777 was predominant in rice/barnyardgrass mixed-cultures. The most significant result of our study is the discovery of an experimental design, target-neighbor mixed-culture in combination with competition indices, can successfully separate allelopathic effects from competition. [ABSTRACT FROM AUTHOR]

Structural equation models are widely used to model relationships among latent unobservable constructs and observable variables. In some studies, the data set used for analysis is comprised of observations that are drawn from a known hierarchical structure and involves missing entries. A two-level structural equation model can be used to analyze such data sets. Direct maximum likelihood methods for analyzing two-level structural equation models are available in software, such as LISREL and Mplus. These software programs also have options to handle missing observations. The authors develop an alternative procedure that uses an expectation maximization (EM) type algorithm. Using appropriate approximations, the procedure can be implemented using simple statistical software in combination with a basic structural equation modeling program. The authors address the implementation of the procedure in detail and provide syntax codes in R, which is available in the public domain, to implement the proposed procedure. The discussion of the procedure is made with reference to the analysis of a data set that studies job characteristic variables. The authors also use simulation studies to examine the performance of the proposed procedure. The results indicate that the proposed method, which is easily accessible to users, represents a reliable alternative for analyzing two-level structural equation models with missing data. [ABSTRACT FROM AUTHOR]

In the present article, we propose and study a new class of nonlinear autoregressive moving-average (ARMA) models, in which each moving-average (MA) coefficient is enlarged to an arbitrary univariate function. We first provide a sufficient condition for the existence of the stationary solution and further discuss the moment structure. We investigate the estimation method to the proposed models. The global estimates of parameters and local linear estimates of functional coefficients are obtained by using a back-fitting algorithm. For testing whether the functional coefficients are some specified parametric forms, a bootstrap test approach is provided. The proposed models are illustrated by both simulated and real data examples. [ABSTRACT FROM AUTHOR]

Parameter estimation and subset selection for separable lower triangular bilinear (SLTBL) models are considered. Under a flat prior, we present an expectation–maximization (EM) algorithm to obtain the maximum likelihood estimation. Furthermore, two sub-procedures are designed to select the best subset model after an initial fitting. Example with two simulated and one real data set illustrate the feasibility and validity of the proposed methods. [ABSTRACT FROM AUTHOR]

The unpredictable survival rate of autologous fat grafting (AFG) seriously affects its clinical application. Improving the survival rate of AFG has become an unresolved issue in plastic surgery. Peroxisome proliferator-activated receptor-γ (PPAR-γ) regulates the adipogenic differentiation of adipocytes, but the functional mechanism in AFG remains unclear. In this study, we established an animal model of AFG and demonstrated the superior therapeutic effect of PPAR-γ regulation in the process of AFG. From day 3 after fat grafting, the PPAR-γ agonist rosiglitazone group consistently showed better adipose integrity, fewer oil cysts, and fibrosis. Massive macrophage infiltration was observed after 7 days. At the same time, M2 macrophages begin to appear. At day 14, M2 macrophages gradually became the dominant cell population, which suppressed inflammation and promoted revascularization and fat regeneration. In addition, transcriptome sequencing showed that the differentially expressed genes in the Rosiglitazone group were associated with the pathways of adipose regeneration, differentiation, and angiogenesis; these results provide new ideas for clinical treatment. [ABSTRACT FROM AUTHOR]

Background Intron-derived long noncoding RNAs with snoRNA ends (sno-lncRNAs) are highly expressed from the imprinted Prader-Willi syndrome (PWS) region on human chromosome 15. However, sno-lncRNAs from other regions of the human genome or from other genomes have not yet been documented. Results By exploring non-polyadenylated transcriptomes from human, rhesus and mouse, we have systematically annotated sno-lncRNAs expressed in all three species. In total, using available data from a limited set of cell lines, 19 sno-lncRNAs have been identified with tissue- and species-specific expression patterns. Although primary sequence analysis revealed that snoRNAs themselves are conserved from human to mouse, sno-lncRNAs are not. PWS region sno-lncRNAs are highly expressed in human and rhesus monkey, but are undetectable in mouse. Importantly, the absence of PWS region sno-lncRNAs in mouse suggested a possible reason why current mouse models fail to fully recapitulate pathological features of human PWS. In addition, a RPL13A region sno-lncRNA was specifically revealed in mouse embryonic stem cells, and its snoRNA ends were reported to influence lipid metabolism. Interestingly, the RPL13A region sno-lncRNA is barely detectable in human. We further demonstrated that the formation of sno-lncRNAs is often associated with alternative splicing of exons within their parent genes, and species-specific alternative splicing leads to unique expression pattern of sno-lncRNAs in different animals. Conclusions Comparative transcriptomes of non-polyadenylated RNAs among human, rhesus and mouse revealed that the expression of sno-lncRNAs is species-specific and that their processing is closely linked to alternative splicing of their parent genes. This study thus further demonstrates a complex regulatory network of coding and noncoding parts of the mammalian genome. [ABSTRACT FROM AUTHOR]

C82H64N12O11Co2, orthorhombic, Pbcn (no. 60), a = 22.286(7) Å, b = 22.725(7) Å, c = 14.056(5) Å, V = 7119(4) Å3, Z = 4, Rgt (F) = 0.0582, wRref (F2 ) = 0.1634, T = 296(2) K. [ABSTRACT FROM AUTHOR]

The stability of the TiO2/ruthenium dye/CuI solid-state solar cell was investigated under continuous simulated sunlight illumination. The cells showed fast degradation under full-spectrum sunlight illumination, but showed rather good stability when the ultraviolet part of the illumination was removed. XPS measurements showed evidence that TiO2 could oxidize CuI in the presence of UV light. The photo-degradation mechanism of the cells is thus discussed on the basis of the photo-oxidative function of TiO2. The long-term stability of the solid-state dye-sensitized solar cell (DSSC) was found to be improved under simulated sunlight by coating the TiO2 porous electrode with an ultra-thin MgO layer, which was able to block the photo-oxidative activity of the TiO2. [ABSTRACT FROM AUTHOR]

We investigate acoustic phonon transmission and thermal conductance in three dimensional (3D) quasi-periodically stubbed waveguides according to the Fibonacci sequence. Results show that the transmission coefficient exhibits the periodic oscillation upon varying the length of stub/waveguide at low frequency, and the period of such oscillation is tunably decreased with increasing the Fibonacci number N. Interestingly, there also exist some anti-resonant dips that gradually develop into wide stop-frequency gaps with increasing N. As the temperature goes up, a transition of the thermal conductance from the decrease to the increase occurs in these systems. When N is increased, the thermal conductance is approximately decreased with a linear trend. Moreover, the decreasing degree sensitively depends on the variation of temperature. A brief analysis of these results is given. [ABSTRACT FROM AUTHOR]

Using the scattering-matrix method, we studied ballistic phonon transmission and thermal conductance at low temperatures in a cylindrical quantum wire with bridge contacts. The transmission coefficient exhibited a stepped profile, which became more evident as the bridge radius increased. When the dimensions of the bridge are identical to those of main wires, we observed a quantum platform of the thermal conductance, even in the presence of interface scattering. When the dimensions of the bridge are smaller than those of main wires, however, we could not observe the quantum platform. We also revealed other interesting physical properties, such as universal quantum thermal conductance and resonant transmission. A brief analysis of these results is given. [ABSTRACT FROM AUTHOR]

The title compound, (C6H14N2)[Cr2O7], consists of a diazabicyclo[2.2.2]octane-1,4-diium cation and a discrete dichromate anion, which are linked in the crystal by N-H…O hydrogen bonds. The cation is ordered and distorted, owing to the confinement and twist of the hydrogen bonds involved. Two CrO4 tetrahedra are joined through a shared O atom to form the dichromate anion. Chiral supramolecular chains of the title compound are built up via N-H…O hydrogen bonds, and C-H…O interactions play subordinate roles in forming the structure. [ABSTRACT FROM AUTHOR]

In the title adduct, C6H12N2·C7H8O2, the orcin and 1,4diazabicyclo[2.2.2]octane moieties are held together by OH···N hydrogen bonds. One-dimensional chiral hydrogenbonded chains are formed along the b axis. Neighbouring chains are held together principally by van der Waals interactions and are interrelated by translation, resulting in a chiral layer. [ABSTRACT FROM AUTHOR]

Mixed-mode chromatography (MMC) is a promising technology for protein separation with high adsorption capacity, good selectivity, salt-tolerance, and facile elution. Expanded bed adsorption (EBA) can capture target proteins directly from bioparticle containing crude feedstock without solid-liquid separation. In this study, MMC and EBA were combined to develop a mixed-mode EBA technique for human serum albumin (HSA) separation. Two mixed-mode EBA resins (using quartz-densified agarose beads and tungsten carbide/agarose composite beads, respectively) with tryptamine as the ligand were prepared (TA-S and TA-T). Static and dynamic adsorption behaviors of HSA were determined under varying conditions and typical adsorption properties of pH dependence and salt-tolerance were found. The performance of the resins in expanded bed was studied, and the dynamic binding capacities at 10% breakthrough (Q10%) of TA-S and TA-T at bed expansion of 1.8 were 27.54 and 18.04 mg/mL settled resin, respectively. Moreover, these two resins were used to separate recombinant HSA (rHSA) from Pichia pastoris culture broth. TA-S showed better separation performance and the purity of rHSA monomer reached to 83.3% with the recovery of 91.6% through a two-step elution process. Total content of rHSA monomer and degraded fragment was 99.8%. The results demonstrate that the combination of MMC and EBA would be a potential platform for protein capture with fewer pretreatments and high process efficiency. [ABSTRACT FROM AUTHOR]

R-spondin proteins are novel Wnt/β-catenin agonists, which signal through their receptors leucine-rich repeat-containing G-protein coupled receptor (LGR) 4/5/6 and substantially enhance Wnt/β-catenin activity. R-spondins are reported to function in embryonic development. They also play important roles in stem cell functions in adult tissues, such as the intestine and mammary glands, which largely rely on Wnt/β-catenin signaling. However, in the skin epithelium and hair follicles, the information about R-spondins is deficient, although the expressions and functions of their receptors, LGR4/5/6, have already been studied in detail. In the present study, highly-enriched expression of the R-spondin family genes (Rspo1/2/3/4) in the hair follicle dermal papilla is revealed. Expression of Rspo1 in the dermal papilla is specifically and prominently upregulated before anagen entry, and exogenous recombinant R-spondin1 protein injection in mid-telogen leads to precocious anagen entry. Moreover, R-spondin1 activates Wnt/β-catenin signaling in cultured bulge stem cells in vitro, changing their fate determination without altering the cell proliferation. Our pioneering study uncovers a role of R-spondin1 in the activation of cultured hair follicle stem cells and the regulation of hair cycle progression, shedding new light on the governance of Wnt/β-catenin signaling in skin biology and providing helpful clues for future treatment of hair follicle disorders. [ABSTRACT FROM AUTHOR]

Crystals of the title compound, C11H11N3O3S2, were obtained from the sulfonyl­ation reaction of 4-methyl­thia­zole-5-carbohydrazide with benzene­sulfonic chloride. The crystal packing is stabilized by intermolecular N—H⋯O and N—H⋯N hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, (C6H14N2)[Cr3O10], consists of a diazabicyclo[2.2.2]octane-1,4-diium cation and a discrete trichromate anion linked by an N-H···O hydrogen bond. Three CrO4 tetrahedra are joined via shared O atoms to form the trichromate anion. Supramolecular rings, which can be described by the graph-set motif R44(26), are built via NH···O hydrogen bonds, and C-H···O interactions play lesser roles in forming the structure. [ABSTRACT FROM AUTHOR]

Two new Co(II) based metal-organic frameworks, namely {[Co5(μ3-OH)2(m-pda)3(bix)4]·2ClO4}n (1) and {[Co2(p-pda)2(bix)2(H2O)]·H2O}n (2), were prepared by hydrothermal reactions of Co(II) salt with two isomeric dicarboxyl tectons 1,3-phenylenediacetic acid (m-pda) and 1,4-phenylenediacetic acid (p-pda), along with 1,3-bis(imidazol-L-ylmethyl)benzene (bix). Both complexes 1 and 2 have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). 1 shows a 6-connected 3-D pcu cationic framework with pentanuclear [Co5(μ3-OH)2(COO)6(bix)2]2+ units, while 2 exhibits a 6-connected 3-D msw net based on [Co2(μ2-H2O)(COO)2]2+ clusters. The results indicate that the different dispositions of the carboxylic groups of dicarboxylates have an important effect on the overall coordination frameworks. Perchlorate anions in 1 can be partly exchanged by thiocyanate and azide anions, however they are unavailable to nitrate anions. Magnetic susceptibility measurements indicate that both 1 and 2 show weak antiferromagnetic interactions between the adjacent Co(II) ions. [ABSTRACT FROM AUTHOR]

An improved iterative approach is proposed to design a diffractive axicon with long focal depth and high lateral resolution. Model designs of the diffractive axicon are carried out in order to convert multi-wavelength uniform beam and Gaussian beam into long focal depth focusing. The numerical results indicate that the designed axicon can achieve long extended focal depth, high transverse resolution and diffraction efficiency simultaneously. Furthermore, a uniform plateau profile can be obtained by using multiple weighted algorithm. The axicon that generates two preset focal depths has been designed, which can also exhibit two perfect long focal depths. [ABSTRACT FROM AUTHOR]

Objective(s): Studies have reported that whole body vibration (WBV) played a vital role in bone remodeling. Circulating serotonin is also involved in negative regulating bone mass in rodents and humans. However, both WBV and inhibition of serotonin biosynthesis may suppress receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclastogenesis in vitro. The purpose of the current study was to investigate the effect of WBV therapy on the levels of serum serotonin in ovariectomized rats. Materials and Methods: Thirty-six-month-old female Sprague Dawley rats weighing 276.15±37.75 g were ovariectomized to induce osteoporosis, and another ten rats underwent sham operation to establish sham control (SHAM) group. After 3 months, ovariectomized rats were divided into three subgroups and then separately treated with WBV, Alendronate (ALN) and normal saline (OVX), SHAM group was given normal saline. After 6 weeks of treatment, rats were sacrificed. Serum serotonin, RANKL, bone turnover markers, and bone mineral density (BMD), bone strength were evaluated. Results: The serum serotonin level was significantly lower in WBV group than OVX and ALN groups (P<0.05 and P<0.001). RANKL levels significantly decreased in WBV and ALN groups compared to OVX group (P<0.001 for both). BMD and biomechanical parameters of femur significantly increased (P<0.05 for both) and bone turnover levels decreased (P<0.001 for both) in WBV group compared to OVX group. Conclusion: These data indicated that WBV enhanced the bone strength and BMD in ovariectomized rats most likely by reducing the levels of circulating serotonin. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to examine whether administration of ulinastatin inhibits pro-inflammatory mediators and ameliorate visceral vasopermeability both in a rat model of major burn, and also in rat cultured endothelial cells stimulated with permeability-evoking mediators. Methods: Plasma levels of tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), myeloperoxidase (MPO), microvascular permeability, and water content of organ tissues were evaluated in a rodent model of a 55% TBSA full-thickness scald injury. Microvascular permeability was also evaluated with a cultured pulmonary microvascular endothelial cells (PMECs) monolayer after stimulation with trypsin, bradykinin, histamine, prostaglandin E2 and burn serum. Results: We found that the plasma levels of TNF-α, CRP, MPO, vascular permeability and water content of heart, lung, kidney, and small intestine tissues were significantly increased in animals after scald injury, and administration of ulinastatin lowered the levels TNF-α, CRP, MPO, vascular permeability and water content of those organ tissues. In vitro, ulinastatin lowered the levels of TNF-α, interleukin-6 (IL-6) and attenuated permeability in PMEC monolayers after being stimulated with bum serum or trypsin, but not by bradykinin, histamine or prostaglandin E2. Conclusions: These results indicate that ulinastatin attenuates the systemic inflammatory response and visceral vasopermeability both in vivo and vitro, and may serve as a therapeutic agent for prevention of systemic inflammatory response and leakage of fluid into tissue after major burn. [ABSTRACT FROM AUTHOR]

We analyzed changes in immunologic values over time for 28 hospitalized patients with pandemic (H1N1) 2009. Levels of interleukin-6, interferon-?, and interleukin-10 increased 1 day after illness onset and then decreased to baseline levels. Levels of virus-specific antibody were undetectable 1 day after illness onset and peaked 36 days later. [ABSTRACT FROM AUTHOR]

In the title compound, (NH4)[ZnCl3(C6H12N4)]·1.5H2O, the ZnII atom is in a tetra­hedral environment, coordinated by one N atom of the hexa­methyl­enetetra­mine ligand and by three Cl atoms. The charge of the hexa­methyl­enetetra­mine­trichloro­zincate(II) anion is counter-balanced by an ammonium cation. Two water mol­ecules, one of which shows disorder and is only partly occupied, are also present. The structure is stabilized by weak inter­molecular O—H⋯N, N—H⋯O and N—H⋯N hydrogen bonds. [ABSTRACT FROM AUTHOR]

Because of the discrete charge storage mechanism, charge trapping memory (CTM) technique is a good candidate for aerospace and military missions. The total ionization dose (TID) effects on CTM cells with Al2O3/HfO2/Al2O3(AHA) high-k gate stack structure under in-situ 10 keV x-rays are studied. The C–V characteristics at different radiation doses demonstrate that charge stored in the device continues to be leaked away during the irradiation, thereby inducing the shift of flatband voltage (Vfb). The dc memory window shows insignificant changes, suggesting the existence of good P/E ability. Furthermore, the physical mechanisms of TID induced radiation damages in AHA-based CTM are analyzed. [ABSTRACT FROM AUTHOR]

Upset errors in 90-nm 64 Mb NOR-type floating-gate Flash memory induced by accelerated 129Xe and 209Bi ions are investigated in detail. The linear energy transfer covers the range from 50 to 99.8 MeV/(mg/cm2). When the memory chips are powered off during heavy ions irradiation, single-event-latch-up and single-event-function-interruption are excluded, and only 0->1 upset errors in the memory array are observed. These error bit rates seem very difficult to achieve and cannot be simply recovered based on the power cycle. The number of error bits shows a strong dependence on the linear energy transfer (LET). Under room-temperature annealing conditions, the upset errors can be reduced by about two orders of magnitude using rewrite/reprogram operations, but they subsequently increase once again in a few minutes after the power cycle. High-temperature annealing can diminish almost all error bits, which are affected by the lower LET 129Xe ions. The percolation path between the floating-gate (FG) and the substrate contributes to the radiation-induced leakage current, and has been identified as the root cause of the upset errors of the Flash memory array in this work. [ABSTRACT FROM AUTHOR]

The60Co-γ ray total ionizing dose radiation responses of 55-nm silicon-oxide-nitride-oxide-silicon (SONOS) memory cells in pulse mode (programmed/erased with pulse voltage) and dc mode (programmed/erased with direct voltage sweeping) are investigated. The threshold voltage and off-state current of memory cells before and after radiation are measured. The experimental results show that the memory cells in pulse mode have a better radiation-hard capability. The normalized memory window still remains at 60% for cells in dc mode and 76% for cells in pulse mode after 300 krad(Si) radiation. The charge loss process physical mechanisms of programmed SONOS devices during radiation are analyzed. [ABSTRACT FROM AUTHOR]