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In order to understand the microsolvation of LiI and CsI in water and provide information about the dependence of solvation processes on different ions, we investigated the LiI(H2O)n- and CsI(H2O)n- (n = 0-6) clusters using photoelectron spectroscopy. The structures of these clusters and their corresponding neutrals were investigated with ab initio calculations and confirmed by comparing with the photoelectron spectroscopy experiments. Our studies show that the structural evolutions of LiI(H2O)n and CsI(H2O)n clusters are very different. The Li–I distance in LiI(H2O)n- increases abruptly at n = 3, whereas the abrupt elongation of the Li–I distance in neutral LiI(H2O)n occurs at n = 5. In contrast to the LiI(H2O)n- clusters, the Cs–I distance in CsI(H2O)n- increases significantly at n = 3, reaches a maximum at n = 4, and decreases again as n increases further. There is no abrupt change of the Cs–I distance in neutral CsI(H2O)n as n increases from 0 to 6. Water molecules interact strongly with the Li ion; consequently, water molecule(s) can insert within the Li+-I- ion pair. In contrast, five or six water molecules are not enough to induce obvious separation of the Cs+-I- ion pair since the Cs–water interaction is relatively weak compared to the Li–water interaction. Our work has shown that the structural variation and microsolvation in MI(H2O)n clusters are determined by the delicate balance between ion–ion, ion–water, and water–water interactions, which may have significant implications for the general understanding of salt effects in water solution. [ABSTRACT FROM AUTHOR]

The egg white protein alterations during the early phase of chicken embryonic development were recently reported by our laboratory. Nevertheless, the original albumen differences between fresh unfertilized and fertilized chicken eggs have not been investigated. By using 2-dimensional gel electrophoresis (2-DE), coupled with matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI- TOF MS/MS) method, 1 ovalbumin protein spot as well as 6 ovalbumin-related protein Y spots were identified showing more than 10-fold differences (P< 0.01) in abundance between fresh unfertilized and fertilized chicken egg whites. Six of these protein spots represented higher intensity in fertilized eggs through 2-DE analysis. It was thus concluded that ovalbumin protein family, especially ovalbumin-related protein Y, may play an important role in embryonic development, which still needs to be validated. This finding will provide insight into embryogenesis to improve our understanding of the functions of ovalbumin family proteins in regulating or supporting embryonic development. [ABSTRACT FROM AUTHOR]

Let f(z) = h(z) + ... be a harmonic mapping of the unit disk U, where h(z) and g(z) are analytic in U. In this paper, we give a lower estimate of the Bloch constant for harmonic mappings of the form L(f), where L represents the linear comp1ex operator L = ... defined on the class of complex-valued C¹ functions in the plane. Also, we obtain three versions of Landau's theorems for harmonic mappings of the form L(f), which are sharp when M = 1 or Λ = 1. [ABSTRACT FROM AUTHOR]

A superparamagnetic reduced graphene oxide-Fe3O4 hybrid composite (rGO-Fe3O4) was prepared via a facile and straightforward method through the solvothermal reaction of iron (III) acetylacetonate .Fe.acac/3/ and graphene oxide (GO) in ethylenediamine (EDA) and water. By this method, chemical reduction of GO as well as the formation of Fe3O4 nanoparticles (NPs) can be achieved in one step. The Fe3O4 NPs are firmly deposited on the surfaces of rGO, avoiding their reassembly to graphite. The rGO sheets prevent the agglomeration of Fe3O4 NPs and enable a uniform dispersion of these metal oxide particles. The size distribution and coverage density of Fe3O4 NPs deposited on rGO can be controlled by varying the initial mass ratio of GO and iron precursor, Fe(acac)3. With an initial mass ratio of GO and Fe.acac/3 of 5:5, the surfaces of rGO sheets are densely covered by spherical Fe3O4 NPs with an average size of 19.9 nm. The magnetic-functionalized rGO hybrid exhibits a good magnetic property and the specific saturation magnetization (Ms) is 13.2 emu g-1. The adsorption test of methylene blue from aqueous solution demonstrates the potential application of this rGO-Fe3O4 hybrid composite in removing organic dyes from polluted water. [ABSTRACT FROM AUTHOR]

The effects of active metals, catalyst supports, and metal loading percentage on the formation of single-walled carbon nanotubes (SWNTs) were studied. In particular, iron, cobalt, and nickel were investigated for SWNTs synthesis. Iron was found to grow better-quality SWNTs compared to cobalt and nickel. To study the effect of catalyst supports, magnesium oxide, silicon oxide, and aluminium oxide were chosen for iron. Among the studied supports, MgO was identified to be a suitable support for iron as it produced SWNTs with better graphitisation determined by Raman analysis. Increasing the iron loading decreased the quality of SWNTs due to extensive agglomeration of the iron particles. Thus, lower metal loading percentage is preferred to grow better-quality SWNTs with uniform diameters. [ABSTRACT FROM AUTHOR]

The electronic transport properties of a kind of phenylacetylene compound (4-mercaptophenyl)-phenylacetylene (MPPA) are studied by the first-principles method. A dithiocarboxylate conjugated linker (-CS2) is used to anchor the molecule to one gold electrode. Rectification behavior is observed, which is mainly brought about by the asymmetrical coupling of electrodes to the molecule. There is a drastic increase in current as the electrodeelectrode distance is reduced, and the rectification ratio increases by 40% as the electrode-electrode distance is diminished from 16Å to 15.7 Å. For comparison, we also perform simulations with the -CS2 linker replaced by thiol linkage. It shows an obvious reduction in current. We find that the stronger interface coupling induced by the -CS2 linker broadens transmission resonances near the Fermi energy, which leads to the current enhancement of the molecular junction with -CS2 linker. [ABSTRACT FROM AUTHOR]

Dynamin is the most-studied membrane fission machinery and has served as a paradigm for studies of other fission GTPases; however, several critical questions regarding its function remain unresolved. In particular, because most dynamin GTPase domain mutants studied to date equally impair both basal and assembly-stimulated GTPase activities, it has been difficult to distinguish their respective roles in clathrin-mediated endocytosis (CME) or in dynamin catalyzed membrane fission. Here we compared a new dynamin mutant, Q40E, which is selectively impaired in assembly-stimulated GTPase activity with S45N, a GTP-binding mutant equally defective in both basal and assembly-stimulated GTPase activities. Both mutants potently inhibit CME and effectively recruit other endocytic accessory proteins to stalled coated pits. However, the Q40E mutant blocks at a later step than S45N, providing additional evidence that GTP binding and/or basal GTPase activities of dynamin are required throughout clathrin coated pit maturation. Importantly, using in vitro assays for assembly-stimulated GTPase activity and membrane fission, we find that the latter is much more potently inhibited by both dominant-negative mutants than the former. These studies establish that efficient fission from supported bilayers with excess membrane reservoir (SUPER) templates requires coordinated GTP hydrolysis across two rungs of an assembled dynamin collar. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the quality of clinical practice guidelines (CPGs) for otorhinolaryngology in China. Materials and Methods: A systematic search of relevant literature databases (CBM, WANFANG, VIP, CNKI, China Guideline Clearinghouse) published between 1978 and March 2012 was undertaken to identify and select CPGs related to otorhinolaryngology. Four independent reviewers assessed the eligible guidelines using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument. Their degree of agreement was evaluated using the intraclass correlation coefficient (ICC). Result: From 170 citations, 21 relevant guidelines were included. The overall agreement among reviewers was moderate (ICC = 0.87; 95% confidence interval [CI], 0.78-0.91). The scores for each of the AGREE domains were the following: "scope and purpose" (mean 6 standard error [SE] = 45.4 ± 4.4; ICC = 0.92), "stakeholder involvement" (mean 6 SE = 30.4 ± 3.1; ICC = 0.81), "rigor of development" (mean 6 SE = 20.9 ± 2.8; ICC = 0.87), "clarity of presentation" (mean 6 SE = 48.8 ± 3.7; ICC = 0.80), "applicability" (mean 6 SE = 12.6 ± 1.7; ICC = 0.72), and "editorial independence" (mean 6 SE = 6.2 ± 0.8; ICC = 0.76). Three guidelines (14%) mentioned updates, and the average update frequency was 7 years. None used the GRADE system. Conclusion: The quality of otorhinolaryngology guidelines in China is low. Greater efforts are needed to provide high-quality guidelines that serve as a useful and reliable tool for clinical decision-making in this field. [ABSTRACT FROM AUTHOR]

Cyclin-dependent kinase 5(CDK5) in complex with its activator, p35 (protein of 35 kDa), is essential for early neurodevelopment in mammals. However, endogenous cleavage of p35 to p25 is associated with neuron death and neurodegenerative disease. Here we show that a peptide (p10') encoding the N-terminal domain of p35 protects against CDK5/p25-induced toxicity in neurons. p10' also prevented the death of neurons treated with the neurotoxin, 1-methyl-4-phenylpyridinium (MPP+), which induces conversion of endogenous p35 to p25, and Parkinson disease (PD)-like symptoms in animals. MPP~ induces CDK5/p25-dependent phosphorylation of peroxiredoxin 2 (PrxZ), resulting in inhibition of its peroxireductase activity and accumulation of reactive oxygen species (ROS). We found that p10' expression inhibited both Prx2 phosphorylation and ROS accumulation in neurons. In addition, p10' inhibited the p25-induced appearance of antigen of the Ki67 antibody (Ki67) and phosphohistone H2AX (γH2AX), classic markers of cell cycle activity and DNA double-strand breakage, respectively, associated with neuron death. Our results suggest that p10 (protein of 10 kDa) is a unique prosurvival domain in p35, essential for normal CDK5/p35 function in neurons. Loss of the p10 domain results in CDK5/p25 toxicity and neurodegeneration in vivo. [ABSTRACT FROM AUTHOR]

Microglia-mediated inflammation is implicated in pathogenesis of neurodegenerative diseases. Oroxylin A, a flavonoid isolated from Scutellariae baicalensis, has been shown to ameliorate microglia activation-mediated neurodegeneration in vivo. The molecular mechanism underlying the inhibitory effects of oroxylin A on microglia activation, however, remains unknown. In the present study, effects of oroxylin A co-treated with lipopolysaccharide (LPS, 100 ng/ml) on LPS-induced activation of cultured microglial BV-2 cells were examined. Nitric oxide (NO) production was determined by Greiss method. Expression of inducible nitric oxide synthase (iNOS), interleukin (IL)-1β and IL-6 was assessed using real-time RT-PCR or Western blot analysis. Furthermore, activation of the nuclear factor kB (NFkB) and the signal transducer and activator of transcription 1 (STAT1) was examined by Western blot analysis and transcription factor DNA-binding activity assay. Our results indicated that oroxylin A (10-100 μM) in a concentration-dependent manner inhibited LPS-induced NO production via blocking iNOS expression at both mRNA and protein levels without affecting the degradation rate of iNOS mRNA. Moreover, oroxylin A significantly attenuated LPS-induced late expression (20 hours after LPS challenge) of IL-1β and IL-6. Furthermore, oroxylin A significantly suppressed LPS-induced JAK2-mediated STAT1 phosphorylation without affecting LPSinduced NFkB-p65 nuclear translocation or NFkB-p65 DNA-binding activity. This is consistent with the finding that AG490, a specific JAK2 inhibitor, significantly inhibited LPS-induced STAT1 phosphorylation with almost completely diminished iNOS expression. These results suggest that oroxylin A, via suppressing STAT1 phosphorylation, inhibits LPS-induced expression of pro-inflammatory genes in BV-2 microglial cells. [ABSTRACT FROM AUTHOR]

Using a Chinese peasant woman, Hu Xinkui's ..., as a looking lens, this article unfolds the socio-cultural change of rural China in the transitional period from around Liberation in 1949 up to 1978, and even into the twenty-first century, covering a wide range of issues regarding footbinding, child brides, forced conscription, bridal lamentation, communist collectivization, and a series of political movements such as land reform, the Great Leap Forward, the Socialist Education Movement, the Four Clearing-ups Movement, and the Poor and Lower-Middle Peasants Association. Hu Xinkui, born in 1934 in Jiangyong County of Hunan Province in south China, was a child bride who was promoted as a director of Women's Affairs after Liberation because of her suppressed inferior status. It was also because of the Liberation-implemented new marriage law that laid the foundation for her husband to divorce her in 1959, for the reason of her apparent infertility and lack of romance, as well as her concern for an unmarried brother, which preoccupied her to the detriment of her own marriage. She remarried in 1964 and retired from her active political life after she had children; since then she has committed herself to being an extremely hard-working housewife. With her husband being an active and honest party cadre (including being the deputy to the 9th Party Congress in 1969), she had to find every possible source to maintain the family finance in order to receive a great deal of visiting guests and peasants, at a cost of neglecting the education of her children, two of whom were addicted to gambling. Her life story manifests how an ordinary village woman engaged with local women's expressive traditions, called ...(women's script) and ... (women's song), and how her personal life changed along with the transformation of China. Also worth noting, the life history interviews with Xinkui were conducted in the company of her daughter and son-in-law, who have assisted my nüshu research for more than a decade -- and they had never learned about Hu Xinkui's past until then. Their participation throws additional reflective light on Xinkui's life experiences in China's changing rural context. With Hu Xinkui's life history as the axis, this article aims to draw attention to the life narrative approach as a tool for collecting ethnographic data and to bring about a rethinking of its use as a conceptual framework. Recognizing the possible limitations of life narrative in terms of its partiality, lapses, mistakes, and exaggeration, I employ narratives from multiple subjects and diverse resources (e.g., literary composition, local oral traditions, and historical documents) to open up the dialogical horizon of a life narration. I demonstrate that life history as a lived experience and an account of life not only speaks to a person's lifeworld; it is also an intertextualization of the voices of multiple subject-positions: narrating subject, addressee, researcher, and the embedded context. In the case of Hu Xinkui, her life narration not only encodes her history and historiography, but also manifests how the next generation, especially her daughter, decodes her story and writes it onto their own. Life narrative in this sense is a convergence of history and culture, whereby history continues and culture persists. [ABSTRACT FROM AUTHOR]

Selectively facilitating apoptosis of activated T cells is essential for the clearance of pathogenic injurious cells and subsequent efficient resolution of inflammation. However, few chemicals have been reported to trigger apoptosis of activated T cells for the treatment of hepatitis without affecting quiescent T cells. In the present study, we found that asiatic acid, a natural triterpenoid, selectively triggered apoptosis of concanavalin A (Con A)-activated T cells in a mitochondria-dependent manner indicated by the disruption of the mitochondrial transmembrane potential, release of cytochrome c from mitochondria to cytosol, caspases activation, and cleavage of PARP. In addition, asiatic acid also induced the cleavage of caspase 8 and Bid and augmented Fas expression in Con A-activated T cells. However, following activation of T cells from MRLlpr/lpr mice with mutation of Fas demonstrated a similar susceptibility to asiatic acid-induced apoptosis compared with normal T cells, suggesting that Fas-mediated death-receptor apoptotic pathway does not mainly contribute to asiatic acid- induced cell death. Furthermore, asiatic acid significantly alleviated Con A-induced T cell-dependent fulminant hepatitis in mice, as assessed by reduced serum transaminases, pro-inflammatory cytokines, and pathologic parameters. Consistent with the in vitro results, asiatic acid also induced apoptosis of activated CD4+ T cells in vivo. Taken together, our results demonstrated that the ability of asiatic acid to induce apoptosis of activated T cells and its potential use in the treatment of T-cell-mediated inflammatory diseases. [ABSTRACT FROM AUTHOR]

Psychoacoustic research suggests that the human auditory system processes noise and tones differently. For example, narrowband noise has a stronger masking effect than a pure tone at the same sound pressure level. Can this be explained by cochlear mechanics, or is the distinction due to central neural processing? In this paper, we review a computational model that simulates wave propagation in the cochlea. The model incorporates recent findings in cochlear electrophysiology and describes wave propagation in both the forward and the backward direction. Simulation shows that the model produces compressive nonlinear responses to tones but quasilinear responses to noise. We may therefore argue that the distinction between tone- and noise-processing is an epiphenomenon of cochlear mechanics. If this is true, we can simplify the computational organization of audio signal-processing front-ends for applications such as hearing aids and auditory prostheses. [ABSTRACT FROM AUTHOR]

Given a so-call checkerboard quadrangulation ◊̄, a checkerboard triangulation … can be obtained by adding two diagonals of all quadrilaterals in ◊̄. In this paper, we develop a local Hermite interpolation method for bivariate C¹ cubic splines on …. By enforcing some additional smoothness conditions across the interior edges of …, a C¹ piecewise cubic polynomial function based on … is constructed by interpolating only the function values and derivatives of first order at the vertices of ◊̄ and none of the normal derivatives at the midpoints of edges in ◊̄ is needed. It. is shown that the new interpolation method produces optimal order approximation of smooth functions. [ABSTRACT FROM AUTHOR]

Through the lens of dialogism, a performance-sensitive perspective, and the conception of emotion as evocative and transformative, this research explores the "expressive depths" of bridal lamentation that was practiced in rural south China. Carrying multiple layers of meaning, bridal lamentation provides all its participants-not only the bride but also her interlocutor and audience-diverse expressive niches from which they intertextually formulate the social wisdom that facilitates identity reconfiguration, emotional transformation, and humanistic cultivation of empathetic listening and the moral spirit of fortitude that would equip the bride for her lifetime. [ABSTRACT FROM AUTHOR]

Spinosyns A and D (spinosad), like many other complex polyketides, are tailored near the end of their biosyntheses through the addition of sugars. SpnG, which catalyzes their 9-OH rhamnosylation, is also capable of adding other monosaccharides to the spinosyn aglycone (AGL) from TDP-sugars; however, the substitution of UDP-D-glucose for TDP-D-glucose as the donor substrate is known to result in a >60000-fold reduction in kcat. Here, we report the structure of SpnG at 1.65 Å resolution, SpnG bound to TDP at 1.86 Å resolution, and SpnG bound to AGL at 1.70 Å resolution. The SpnG-TDP complex reveals how SpnG employs N202 to discriminate between TDP- and UDP-sugars. A conformational change of several residues in the active site is promoted by the binding of TDP. The SpnG-AGL complex shows that the binding of AGL is mediated via hydrophobic interactions and that H13, the potential catalytic base, is within 3 Å of the nucleophilic 9-OH group of AGL. A model for the Michaelis complex was constructed to reveal the features that allow SpnG to transfer diverse sugars; it also revealed that the rhamnosyl moiety is in a skew-boat conformation during the transfer reaction. [ABSTRACT FROM AUTHOR]

Given a so-call checkerboard quadrangulation ◊̄, a checkerboard triangulation … can be obtained by adding two diagonals of all quadrilaterals in ◊̄. In this paper, we develop a local Hermite interpolation method for bivariate C¹ cubic splines on …. By enforcing some additional smoothness conditions across the interior edges of …, a C¹ piecewise cubic polynomial function based on … is constructed by interpolating only the function values and derivatives of first order at the vertices of ◊̄ and none of the normal derivatives at the midpoints of edges in ◊̄ is needed. It is shown that the new interpolation method produces optimal order approximation of smooth functions. [ABSTRACT FROM AUTHOR]

Epithelial Na+ channel (ENaC)-mediated Na+ absorption and BK channel-mediated K+ secretion in the cortical collecting duct (CCD) are modulated by flow, the latter requiring an increase in intracellular Ca2+ concentration ([Ca2+]i), microtubule integrity, and exocytic insertion of preformed channels into the apical membrane. As axial flow modulates HCO3- reabsorption in the proximal tubule due to changes in both luminal Na+/H+ exchanger 3 and H+-ATPase activity (Du Z, Yan Q, Duan Y, Weinbaum S, Weinstein AM, Wang T. Am J Physiol Renal Physiol 290: F289-F296, 2006), we sought to test the hypothesis that flow also regulates H+-ATPase activity in the CCD. H+-ATPase activity was assayed in individually identified cells in microperfused CCDs isolated from New Zealand White rabbits, loaded with the pHsensitive dye BCECF, and then subjected to an acute intracellular acid load (NH4Cl prepulse technique). H+-ATPase activity was defined as the initial rate of bafilomycin-inhibitable cell pH (pHi) recovery in the absence of luminal K+, bilateral Na+, and CO2/HCO3-, from a nadir pH of ∼6.2. We found that 1) an increase in luminal flow rate from ~1 to 5 nl·min-1·mm-1 stimulated H+-ATPase activity, 2) flowstimulated H+ pumping was Ca2+ dependent and required microtubule integrity, and 3) basal and flow-stimulated pHi recovery was detected in cells that labeled with the apical principal cell marker rhodamine Dolichos biflorus agglutinin as well as cells that did not. We conclude that luminal flow modulates H+-ATPase activity in the rabbit CCD and that H+-ATPases therein are present in both principal and intercalated cells. [ABSTRACT FROM AUTHOR]

A class of G-semipreinvex functions, which are some generalizations of the semipreinvex functions, and the G-convex functions, is introduced. Examples are given to show their relations among G-semipreinvex functions, semipreinvex functions and G-convex functions. Some characterizations of G-semipreinvex functions are also obtained, and some optimality results are given for a class of G-semipreinvex functions. Ours results improve and generalize some known results. [ABSTRACT FROM AUTHOR]

The location of the triple line as a function of time has been recorded for a series of organic liquids, with various surface tension to viscosity ratios, wicking upward a rough Cu6Sn5/Cu intermetallic (IMC) substrate. The complex topographical features of such an IMC rough surface are characterized by surface porosity and surface roughness. A theoretical model for wicking upward a rough surface has been established by treating the rough IMC surface as a two-dimensional porous medium featuring a network of open microtriangular grooves. The model is verified against experimental data. The study confirms that the kinetics of capillary rise of organic liquids in a nonreactive flow regime over a porous surface having arbitrary but uniformly distributed topographical features involves (i) surface topography metrics (i.e., permeability, tortuosity/porosity, and geometry of the microchannel cross section); (ii) wicking features (i.e., contact angle and filling factor); and (iii) physical properties of liquids (i.e., surface tension and viscosity). An excellent agreement between theoretical predictions and experimentally obtained data proves, for a selected filling factor η, validity of the analytically established model. Scaled data sets show that, for a given rough surface topography, (i) wicking kinetics of considered liquids depend on properties of liquids, that is, surface tension to viscosity ratios and contact angles; (ii) the filling factor for all tested liquids is an invariant, offering good prediction within the range of ∼0.9–1.0. The distance of the wicking front versus square root of time relationship was well established throughout the whole considered wicking evolution time. [ABSTRACT FROM AUTHOR]

Objective: To evaluate bony changes in the skull base after radiotherapy by computed tomography (CT) and their correlation with local recurrence in patients with nasopharyngeal carcinoma (NPC) without previous involvement of the skull base. Design: Retrospective study. Setting: Sun-Yat Sen University Cancer Center. Methods: The records of 80 patients with NPC during the period from January 1992 to December 2005 were reviewed. All patients had been treated with radical radiotherapy or chemoradiotherapy at standard doses and were followed up with plain and contrast-enhanced CT every 6 months for 45.5 (range 12-108) months. Main Outcome Measures: The types, areas, time of the first occurrence after radiotherapy and development of the postradiation bony changes of the skull base, and local recurrence rates of NPC were measured. Results: Eighteen patients (22.5%) had sclerosis in some area of the skull base, and the sclerosis in 5 (27.8%) of these patients changed into osteoporosis in 1 to 5 years after its appearance. Seventeen patients (21.3%) had osteolysis. The local recurrence rate of patients with osteolysis was observed to be significantly higher than that of patients with sclerosis (p , .0001). Conclusions: The appearance of osteolytic changes in the skull base during follow-up of patients with NPC who had normal skull base morphology before treatment was associated with tumour recurrence. [ABSTRACT FROM AUTHOR]

Green fluorescent proteins (GFPs) are widely used in tracing transgene expression and have been known as convenient and efficient markers for plant transformation. However, sometimes researchers are still puzzled by the weak fluorescence since it makes the observation of GFP signals and confirmation of transgenic plants difficult. In this investigation, we explored the possibility of enhancing the weak signals by changing the pH environment of detection and took microplate reader as a more effective instrument compared to traditional fluorescent microscope to detect the weak signals. It was found that the fluorescence intensity of enhanced GFP (EGFP) in transgenic plants can be increased 2-6 folds by altering the environmental pH, and the concentration of EGFP at a large scale (ranged from 20 ng/ml to 20 μg/ml) can be detected and quantified. It can exclude the influence of degradation fragment and hence facilitate later analysis; these advantages were further verified by comparing with western blotting and confocal microscopy. It was reliable and effective for the qualitative and quantitative analysis of transgenic plants and was more suitable for the detection of very weak fluorescent signals. [ABSTRACT FROM AUTHOR]

A theoretical model of a capillary driven flow of liquid metal through topography features of rough surfaces has been verified by a study of molten solder (Sn–Pb) spreading over Cu6Sn5/Cu3Sn/Cu intermetallic (IMC) substrates. Flow through microgrooves over a rough IMC substrate is considered as spreading through an isotropic porous medium featuring a network of open microgrooves having predefined free-flow area cross sections. The relative margin of deviation between theoretically predicted and empirically determined locus of points of triple line locations is within the range of 5–15%. This margin supports the validity of the developed, analytically formulated square root power law model for a whole spreading domain in terms of (i) geometry of topographical features of the rough surface (i.e., effective intrinsic permeability, porosity/tortuosity, and microchannel cross section geometry), (ii) wetting/spreading features (equilibrium contact angle and filling factor), and (iii) molten metal/substrate properties (viscosity and surface tension). Experimental data involving triple line kinetics represent the data set of locations of the triple line versus time obtained by in situ monitoring of the spreading of molten metal systems over IMC substrates by using the controlled atmosphere hot stage microscopy. [ABSTRACT FROM AUTHOR]

NDRG1 and KAI1 belong to metastasis suppressor genes, which impede the dissemination of tumor cells from primary tumors to distant organs. Previously, we identified the metastasis promoting transcription factor, ATF3, as a downstream tar- get of NDRG1. Further analysis revealed that the KAI1 promoter contained a consensus binding motif of ATF3, suggesting a pos- sibility that NDRG1 suppresses metastasis through inhibition of ATF3 expression followed by activation of the KAI1 gene. In this report, we found that ectopic expression of NDRG1 was able to augment endogenous KAI1 gene expression in prostate cancer cell lines, whereas silencing NDRG1 was accompanied with significant decrease in KAI1 expression in vitro and in vivo. In addition, our results of ChIP analysis indicate that ATF3 indeed bound to the promoter of the KAI1 gene. Importantly, our promoter-based analysis revealed that ATF3 modulated KAI1 transcription through cooperation with other endogenous transcription factor as co-activator (ATF3-JunB) or co-repressor (ATF3-NFκB). Moreover, loss of KAI1 expression significantly abrogated NDRG1-mediated metastatic suppression in vitro as well as in a spontaneous metastasis animal model, indicating that KAI1 is a functional downstream target of the NDRG1 pathway. Our result of immunohistochemical analysis showed that loss of NDRG1 and KAI1 occurs in parallel as prostate cancer progresses. We also found that a combined expression status of these two genes serves as a strong independent prognostic marker to predict metastasis-free survival of prostate cancer patients. Taken together, our result revealed a novel regulatory network of two metastasis suppressor genes, NDRG1 and KAI1, which together concerted metastasis-suppressive activities through an intrinsic transcriptional cascade. [ABSTRACT FROM AUTHOR]

Several residues in the third extramembrane segment (EM3) of adrenal cytochrome b561 have been proposed to be involved in this cytochrome's interaction with ascorbate, but there has been no systematic evaluation of residues in the segment. We used alanine scanning mutagenesis to assess the functional and structural roles of the EM3 residues and several adjacent residues (residues 70-85) in the bovine cytochrome. Each alanine mutant was expressed in a bacterial system, solubilized with detergent, and affinity-purified. The recombinant proteins contained approximately two hemes per monomer and, except for R74A, retained basic functionality (=94% reduced by 20 mM ascorbate). Equilibrium spectrophotometric titrations with ascorbate were used to analyze the a-band line shape and amplitude during reduction of the high- and low-potential heme centers (bH and bL, respectively) and the midpoint ascorbate concentrations for the bH and bL transitions (CH and CL, respectively). Y73A and K85A markedly narrowed the bH a-band peak; other mutants had weaker effects or no effect on bH or bL spectra. Relative changes in CH for the mutants were larger than changes in CL, with 1.5-2.9-fold increases in CH for L70A, L71A, Y73A, R74A, N78A, and K85A. The amounts of functional bH and bL centers in additional Arg74 mutants, assessed by ascorbate titration and EPR spectroscopy, declined in concert in the following order: wild type > R74K > R74Q > R74T and R74Y > R74E. The results of this first comprehensive experimental test of the proposed roles of EM3 residues have identified residues with a direct or indirect impact on ascorbate interactions, on the environment of the bH heme center, and on formation of the native bH-bL unit. Surprisingly, no individual EM3 residue was by itself indispensable for the interaction with ascorbate, and the role of the segment appears to be more subtle than previously thought. These results also support our topological model of the adrenal cytochrome, which positions bH near the cytoplasmic side of the membrane. [ABSTRACT FROM AUTHOR]

I -Aminocyclopropane- I -carboxylic acid (ACC) deaminase (ACCD) is a pyridoxal 5'-phosphate (PLP)-dependent enzyme that cleaves the cyclopropane ring of ACC, to give α-ketobutyric acid and ammonia as products. The cleavage of the Cα–Cβ bond of an amino acid substrate is a rare event in PLP-dependent enzyme catalysis. Potential chemical mechanisms involving nucleophile- or acid-catalyzed cyclopropane ring opening have been proposed for the unusual transformation catalyzed by ACCD. but the actual mode of cyclopropane ring cleavage remains obscure. In this report, we aim to elucidate the mechanistic features of ACCD catalysis by investigating the kinetic properties ofACCD from Pseudomona.s sp. ACP and several of its mutant enzymes. Our studies suggest that the pKa of the conserved active site residue, Tyr294, is lowered by a hydrogen bonding interaction with a second conserved residue, Tyr268. This allows Tyr294 to deprotonate the incoming amino group of ACC to initiate the aldimine exchange reaction between ACC and the PLP coenzyme and also likely helps to activate Tyr294 for a role as a nucleophile to attack and cleave the cyclopropane ring of the substrate. In addition, solvent kinetic isotope effect (KIE), proton inventory, and 13C KIE studies of the wild type enzyme suggest that the Cα–Cβ bond cleavage step in the chemical mechanism is at least partially rate-limiting under kcat/Km conditions and is likely preceded in the mechanism by a partially rate-limiting step involving the conversion of a stable gens-diamine intermediate into a reactive external aldimine intermediate that is poised for cyclopropane ring cleavage. When viewed within the context of previous mechanistic and structural studies of ACCD enzymes, our studies are most consistent with a mode of cyclopropane ring cleavage involving nucleophilic catalysis by Tyr294. [ABSTRACT FROM AUTHOR]

Thiopeptides are a class of clinically interesting and highly modified peptide antibiotics. Their biosyntheses share a common paradigm for characteristic core formation but differ in tailoring to afford individual members. Herein we report an unusual deesterification-amidation process in thiostrepton maturation to furnish the terminal amide moiety. TsrB, serving as a carboxylesterase, catalyzes the hydrolysis of the methyl ester intermediate to provide the carboxylate intermediate, which can be converted to the amide product by an amidotransferase, TsrC. These findings revealed a C-terminal methylation of the precursor peptide, which is cryptic in thiostrepton biosynthesis but potentially common in the formation of its homologous series of thiopeptides that vary in the C-terminal form as methyl ester, carboxylate, or amide. [ABSTRACT FROM AUTHOR]

The solid solution series CexZr1-xO2(x= 0.2, 0.3, 0.4, 0.5, 0.6, 0.8, 1.0) with a bimodal pore structure was prepared by the citric acid sol−gel method. Results from X-ray diffraction, Raman spectroscopy, scanning electron microscopy, mercury porosimetry, and N2adsorption/desorption measurements indicated that the physical properties of the solid solutions were significantly affected by the Ce/Zr molar ratio and the calcination temperatures. These solid solutions can be used in the synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide. Results indicated that the structure of the solid solutions and the Ce/Zr molar ratio in CexZr1-xO2were the key factor in determining the catalytic activity for the synthesis of DMC. Higher catalytic performance was observed with a 1:1 Ce/Zr molar ratio at a calcination temperature of 1273 K. 1,1,1-Trimethoxymethane (TMM) was used to remove residual H2O in situ, and was found to increase the methanol conversion from 1.8 to 7.9% at 373 K under a pressure of 20 MPa after 24 h. The combination of the bimodal porous catalyst with an effective H2O removal agent gave a methanol conversion of 10.4% at 373 K, under 12 MPa after 34 h. The catalytic activity was almost doubled when the ionic liquid 1-ethyl-3-methylimidazolium bromide was loaded on Ce0.5Zr0.5O2, which may be a promising means for selective production of DMC from CO2and CH3OH. [ABSTRACT FROM AUTHOR]

Unique spindle-shaped nanoporous anatase Ti02 mesocrystals with a sngle-crystal-like structure and tunable sizes were successfully fabricated on a large scale through mesoscale assembly in the tetrabutyl titanate-acetic acid system without any additives under solvothermal conditions. A complex mesoscale assembly process involving slow release of soluble species from metastable solid precursors for the continuous formation of nascent anatase nanocrystals, oriented aggregation of tiny anatase nanocrystals, and entrapment of in situ produced butyl acetate as a porogen was put forward for the formation of the anatase mesocrystals. It was revealed that the acetic acid molecules played multiple key roles during the nonhydrolytic processing of the [OO1]-oriented, singlecrystal-like anatase mesocrystals. The obtained nanoporous anatase mesocrystals exhibited remarkable crystalline-phase stability (i.e., the pure phase of anatase can be retained after leing annealed at 900 °C) and improved performance as anode materials for lithium ion batteries, which could be largely attributed to the intrinsic single-crystal-like nature as well as high porosity of the nanoporous mesocrystals. [ABSTRACT FROM AUTHOR]

Abstract: This paper discusses the application of the content analysis method in the analysis of food safety reports. Several subjects, such as food chain, food category, violative testing Items, hazard of violative food samples and data in food safety reports from April 1st to June 1st 2009, were investigated. Based on the research, 50% of food safety reports selected came from the food distribution stage, 32% of the food safety reports mentioned one or several food additives. Among the selected reports, “beverages”, “cereals and cereal products”, and “salts, spices, soups, sauces, salads and protein products” are the top three (3) food groups mentioned. Only 20% of food safety reports contained the treatment information about violative food samples, while 8% contained a description about the potential hazard. Over 50% of the food safety reports were described with the types of violative food samples and Violation Rate. [ABSTRACT FROM AUTHOR]

Background: Purchasers can play an important role in eliminating racial and ethnic disparities in health care. A need exists to develop a compelling "business case" from the employer perspective to put, and keep, the issue of racial/ethnic disparities in health care on the quality improvement agenda for health plans and providers. Methods: To illustrate a method for calculating an employer business case for disparity reduction and to compare the business case in two clinical areas, we conducted analyses of the direct (medical care costs paid by employers) and indirect (absenteeism, productivity) effects of eliminating known racial/ethnic disparities in mammography screening and appropriate medication use for patients with asthma. We used Markov simulation models to estimate the consequences, for defined populations of African-American employees or health plan members, of a 10% increase in HEDIS mammography rates or a 10% increase in appropriate medication use among either adults or children/adolescents with asthma. Results: The savings per employed African-American woman aged 50-65 associated with a 10% increase in HEDIS mammography rate, from direct medical expenses and indirect costs (absenteeism, productivity) combined, was $50. The findings for asthma were more favorable from an employer point of view at approximately $1,660 per person if raising medication adherence rates in African-American employees or dependents by 10%. Conclusions: For the employer business case, both clinical scenarios modeled showed positive results. There is a greater potential financial gain related to eliminating a disparity in asthma medications than there is for eliminating a disparity in mammography rates. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the antihypertensive effect of Xinjiang red raspberry fruit ethyl acetate extract (EER) on spontaneously hypertensive rats (SHR) and its possible mechanism from antioxidant perspective. Materials and Methods: The SHR rats were randomly divided into 3 groups, and treated with EER low dose (EERL, 100 mg/kg/d), high dose (EERH, 200 mg/kg/d), and water (SHR) through gastric gavage daily for 5 weeks. Another 8 age-matched male Wistar-Kyoto rats were used as normotensive group (WKY). The systolic blood pressure (SBP) was measured by noninvasive tail-cuff method once a week. At the end of the treatment, blood samples were collected and serum concentrations of nitric oxide (NO), superoxide dismutase (SOD), malondialchehyche (MDA), and plasma endothelin (ET) were determined. Results: Treatment of SHR rats with EER lowered the blood pressure compared with that treated with water (SHR), and the high dose showed more significant reduction in blood pressure. Treatment of SHR rats with EER increased serum NO and SOD levels and lowered ET and MDA levels. As compared with control group, NO levels were increased significantly in EERL (P < 0.01), SOD was elevated more significantly in both EERL and EERH (P < 0.01); MDA was decreased significantly in EERH group (P < 0.05), whereas plasma ET decreased more significantly in the EERH group (P < 0.05). Conclusions: The red raspberry extracts demonstrated a dose-dependent antihypertensive effects in SHR and this may be related to increased NO activation and improved vascular endothelial dysfunction via antioxidation. These results confirmed that raspberries rich in polyphenols have potential cardiovascular protective effects. [ABSTRACT FROM AUTHOR]

Background and purpose: A comparative treatment planning study was undertaken between proton beam therapy (PBT) and intensity-modulated x-ray therapy (IMXT) for patients with recurrent nasopharyngeal carcinoma (NPC), to assess the potential benefits and limitations of the two treatment modalities. Materials and methods: We retrospectively analyzed seven patients with recurrent NPC treated at our proton center with PBT from 2004 to 2007. Eclipse proton treatment planning system and Eclipse inverse treatment planning system for IMXT were employed. For each patient, the IMXT plan was optimized with nine evenly spaced coplanar fields. Three coplanar beams and passive scattering mode were used for PBT. The dose prescription in cobalt Gray equivalent (CGE) for gross tumor volume (GTV) was 66CGE and for planning target volume (PTV), 62.7CGE. Dose-volume histograms (DVH) were used to evaluate the difference in dosimetric distributions for the target volume and the organs at risk (OARs). Results: Optimal target volume coverage and similar target conformation were achieved in both PBT and IMXT. Median conformity index was 0.72 and 0.75 (p=0.15) and median inhomogeneity coefficient was 0.14 and 0.10 (p=0.08) for PBT and IMXT, respectively. Dose to OARs was significantly lower in PBT plans than IMXT. Median maximal dose to the brainstem was 27.89CGE(cobalt Gray equivalent) and 42.45Gy (p< 0.01), and the dose to 5% of the brainstem(D5) was 12.83CGE and 19.47Gy (p< 0.001 ), for PBT and IMXT, respectively. Median maximal dose to the spinal cord was 8.38CGE and 22.91Gy (p< 0.004), and the dose to 5% of the spinal cord was 2.18CGE and 13.62Gy (p< 0.001), for PBT and IMXT, respectively. Conclusions: The use of PBT, when compared with IMXT, resulted in similar levels of tumor conformation. PBT, however, exposed the OARs to a significantly lower dose, effectively sparing the brainstem, spinal cord, optic nerve and chiasm, temporal lobes and parotid glands. The superior dose distributions possible with PBT should translate into reduced morbidity and improved quality of life. [ABSTRACT FROM AUTHOR]

A coplanar waveguide (CPW)-fed planar monopole antenna with triple band operation for worldwide interoperability for microwave access (WiMAX) and wireless local area network (WLAN) applications is presented. The antenna, which occupies a small size of 25 (L) × 25 (W) × 0.8 (H) mm3, is simply composed of a pentagonal radiating patch with two bent slots. By carefully selecting the positions and lengths of these slots, good dual stopband rejection characteristic of the antenna can be obtained, so that three operating bands covering 2.14–2.85, 3.29–4.08, and 5.02–6.09 GHz can be achieved. The measured results also demonstrate that the proposed antenna has good omnidirectional radiation patterns with appreciable gain across the operating bands, and is thus suitable to be integrated within the portable devices for WiMAX/WLAN applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2405–2408, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25497 [ABSTRACT FROM AUTHOR]

A novel planar monopole slot antenna that possesses a controllable band-notched property for ultra-wideband (UWB) applications is presented. The antenna, which consists of a square slot patch with a vertical coupled strip, only occupies a small size of 15 (L) × 15 (W) × 1.6 (H) mm3. By properly inserting a thin gap between the coupled strip and the slot patch, the antenna can achieve a wide bandwidth covering 3.05–11.15 GHz with a sharp rejection band of 5.12–6.08 GHz, where the frequency rejection performance can be controlled flexibly by employing various strip widths and thin gaps. Good measured omnidirectional radiation patterns and transmission responses also indicate that the proposed antenna is well suitable for UWB operation. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2624–2627, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25550 [ABSTRACT FROM AUTHOR]

Wang in [1] solved an open problem described by Farm in [2], he constructed a C2 quintic spline interpolation scheme on a refined triangulation. In this paper, we would like to improve Wang's study by enforcing some additional smoothness conditions across the interior edges of Wang's refinement of triangulation Δ. The results imply that our improvement interpolation scheme is more effective than other counterparts. [ABSTRACT FROM AUTHOR]

Aims and objectives. The purpose of this study was to explore the prevalence and risk factors of urine retention among posthaemorrhoidectomy recipients. Background. Haemorrhoids are one of the most common functional disorders of the anus. The Haemorrhoidectomy surgical procedure is one of the primary treatments for more severe haemorrhoidal occurrences, such as for third- and/or fourth-degree haemorrhoid conditions. Urine retention is a common acute complication after operation, but rare study conducted by nurses in Taiwan to explore the prevalence and risk factors. Design. A retrospective chart review was conducted. Methods. Data from a prospectively maintained database on patients who had undergone haemorrhoidectomy between April 2004 - August 2008 were retrospectively analysed. A total of 469 charts were used in this analysis. The following outcomes were studied: patient profiles, haemorrhoid type and severity, anaesthesia methods, length of operating room stay, urine retention and management, intravenous fluid given during operation and length of stay. Results. The overall urinary retention rate was 32·8% ( n = 153). Significant risk factors associated with postoperative urinary retention included severity of haemorrhoid and anaesthesia methods. Logistic regression analysis revealed that epidural anaesthesia ( p = 0·008), spinal anaesthesia ( p = 0·016) and haemorrhoids with a severity of three degrees or higher ( p = 0·017) were predictors of urinary retention post haemorrhoidectomy. Conclusions. Acute urinary retention can have an adverse effect on a patient's quality of care. Careful follow-up of patients with these risk factors can help nurses spot posthaemorrhoidectomy urinary retention early. Relevance to clinical practice. The prevalence of acute urinary retention post haemorrhoidectomy is common. Surgical ward nurses should therefore take the responsibility regarding the impact of urinary retention and seeking appropriate nursing interventions of induced urination. [ABSTRACT FROM AUTHOR]

In this article I analyze a changben (song book) ballad of Liang Shanbo and Zhu Yingtai transliterated into nüshu ("female writing"), a script circulated exclusively among peasant women in Jiangyong County, Hunan Province, China. Conceptualizing genre as the intertextualization of an event, narrative poetics, and social context, I will discuss how the male-composed Liang-Zhu narrative ballad was read and received by nüshu women in rural Jiangyong, and through this process trace out the expressive niches of the changben genre. I will show that despite its transcription into nüshu, the Liang-Zhu changben narrative did not merely mirror Jiangyong women's life worlds. Instead, it reflected and in the meantime refracted their inner feelings and social reality. Reflection and refraction intersect to create an expressive arena where audiences articulate their intricate sensibilities of conforming to the existing social order while simultaneously transforming it, and where they can project unrealistic but fulfilling fantasies of existence. Through changben, they contemplate being in-the-world, probing beneath the surface of existence, and searching for hope in everyday life. [ABSTRACT FROM AUTHOR]

The in vitro characterization of the catalytic activity of DesVII, the glycosyltransferase involved in the biosynthesis of the macrolide antibiotics methymycin, neomethymycin, narbomycin, and pikromycin in Streptomyces venezuelae, is described. DesVII is unique among glycosyltransferases in that it requires an additional protein component, DesVIII, for activity. Characterization of the metabolites produced by a S. venezuelae mutant lacking the desVIII gene confirmed that desVIII is important for the biosynthesis of glycosylated macrolides but can be replaced by at least one of the homologous genes from other pathways. The addition of recombinant DesVIII protein significantly improves the glycosylation efficiency of DesVII in the in vitro assay. When affinity-tagged DesVII and DesVIII proteins were coproduced in Escherichia coli, they formed a tight (αβ)3 complex that is at least 10³-fold more active than DesVII alone. The formation of the DesVII/DesVIII complex requires coexpression of both genes in vivo and cannot be fully achieved by mixing the individual protein components in vitro. The ability of the DesVII/DesVIII system to catalyze the reverse reaction with the formation of TDP-desosamine was also demonstrated in a transglycosylation experiment. Taken together, our data suggest that DesVIII assists the folding of DesVII during protein production and remains tightly bound during catalysis. This requirement must be taken into consideration in the design of combinatorial biosynthetic experiments with new glycosylated macrolides. [ABSTRACT FROM AUTHOR]

In this paper, the analytical solution of stress field for a strained reinforcement layer bonded to a lip-shaped crack under a remote mode III uniform load and a concentrated load is obtained explicitly in the series form by using the technical of conformal mapping and the method of analytic continuation. The effects of material combinations, bond of interface and geometric configurations on interfacial stresses generated by eigenstrain, remote load and concentrated load are studied. The results show that the stress concentration and interfacial stresses can be reduced by rational material combinations and geometric configurations designs for different load forms. [ABSTRACT FROM AUTHOR]

Ciliate Euplotes octocarinatus centrin (EoCen) is a member of the EF-hand superfamily of calcium-binding proteins. It has been proven, using Tb as a fluorescence probe, that EoCen has four calcium-binding sites. The sensitized emission arises from nonradiative energy transfer between the three tyrosine residues (Tyr46, Tyr72, and Tyr79) of the N-terminal half and the bound Tb ions. To determine the most critical of the three tyrosine residues for the process of fluorescence resonance energy transfer, six mutants of the N-terminal domain of EoCen, which contain one (N-Tyr46/N-Tyr72/N-Tyr79) or two (N-Y46F/N-Y72F/N-Y79F) tyrosine residues, were obtained by site-directed mutagenesis. The aromatic residue-sensitized Tb fluorescence of N-Y79F was most affected, displaying a 50% reduction compared with wild-type N-EoCen. Among the tyrosines, Tyr79 is the shortest mean distance from the protein-bound Tb (at sites I/II), as calculated via the Förster mechanism. The steady-state and time-resolved fluorescence parameters of the wild-type N-EoCen and the three double mutants suggest that Tyr79, which exists in a hydrophobic environment, has the highest quantum yield and a relatively long average lifetime. The decay of Tyr79 is the least heterogeneous among the three tyrosine residues. In addition, molecular modeling shows that a critical hydrogen bond is formed between the 4-hydroxyl group of Tyr79 and the oxygen from the side chains of the residue Asn39. Kinetic experiments on tyrosine and Tb fluorescence demonstrate that tyrosine fluorescence quenching is largely due to the self-assembly of EoCen, and that the quenching degrees of the mutants differ. Resonance light scattering and crosslinking analysis carried out on the full-length single mutants (Y46F, Y72F, and Y79F) showed that Tyr79 also plays the most important role in the Tb-dependent self-assembly of EoCen among the three tyrosines. [ABSTRACT FROM AUTHOR]

Trapa maximowiczii is a floating-leaved macrophyte common in China. The plant population in East Bay, Lake Taihu, has been expanding rapidly in recent years. In order to better understand the mechanisms controlling the population dynamics in this species, two outdoor experiments were conducted from 9 May to 8 July 2007, evaluating the effect on the growth of T. maximowiczii of different nutrient levels in water column and sediment. Results showed that high concentration of nutrients (nitrogen and phosphorous) in water led to significant increases in rosette diameter and plant dry weight, dry weight of aquatic roots and anchoring roots, but had no effect on plant height or main stem node count. Phosphorus enrichment resulted in increases in plant dry weight and seed number. However, no such difference was observed between the nitrogen enrichment treatment and the control. Sediment fertility had significant effects on plant growth. Plant height, plant dry weight, dry weight of aquatic and anchoring roots, and maximum rosette diameter were significantly greater in high-nutrient sediment than those in low-nutrient sediment. This study suggests that eutrophication of water (especially increasing phosphorus loading) and accumulated nutrients in sediment may be among the causes leading to increasing biomass of the floating-leaved macrophyte T. maximowiczii in East Bay of Lake Taihu. [ABSTRACT FROM AUTHOR]

While reversible histone modifications are linked to an ever-expanding range of biological functions, the demethylases for histone H4 lysine 20 and their potential regulatory roles remain unknown. Here we report that the PHD and Jumonji C (JmjC) domain-containing protein, PHF8, while using multiple substrates, including H3K9me1/2 and H3K27me2, also functions as an H4K20me1 demethylase. PHF8 is recruited to promoters by its PHD domain based on interaction with H3K4me2/3 and controls G1–S transition in conjunction with E2F1, HCF-1 (also known as HCFC1) and SET1A (also known as SETD1A), at least in part, by removing the repressive H4K20me1 mark from a subset of E2F1-regulated gene promoters. Phosphorylation-dependent PHF8 dismissal from chromatin in prophase is apparently required for the accumulation of H4K20me1 during early mitosis, which might represent a component of the condensin II loading process. Accordingly, the HEAT repeat clusters in two non-structural maintenance of chromosomes (SMC) condensin II subunits, N-CAPD3 and N-CAPG2 (also known as NCAPD3 and NCAPG2, respectively), are capable of recognizing H4K20me1, and ChIP-Seq analysis demonstrates a significant overlap of condensin II and H4K20me1 sites in mitotic HeLa cells. Thus, the identification and characterization of an H4K20me1 demethylase, PHF8, has revealed an intimate link between this enzyme and two distinct events in cell cycle progression. [ABSTRACT FROM AUTHOR]

The effect of a copper-embedded barrel on the performance of a helix slow-wave structure (SWS) has been studied theoretically and experimentally. The heat dissipation capability and cold-test characteristics of the SWSs with a monel barrel, a normal copper barrel, and a copper-embedded monel barrel have been analyzed and compared. With its combination of high mechanical strength and good thermal conductivity, the copper-embedded monel barrel enables better heat dissipation capability than the other barrel types and has low RF losses. [ABSTRACT FROM AUTHOR]

A model of cochlear mechanics is described in which force-producing outer hair cells (OHC) are embedded in a passive cochlear partition. The OHC mechanoelectrical transduction current is nonlinearly modulated by reticular-lamina (RL) motion, and the resulting change in OHC membrane voltage produces contraction between the RL and the basilar membrane (BM). Model parameters were chosen to produce a tonotopic map typical of a human cochlea. Time-domain simulations showed compressive BM displacement responses typical of mammalian cochleae. Distortion product (DP) otoacoustic emissions at 2f1-f2 are plotted as isolevel contours against primary levels (L1,L2) for various primary frequencies f1 and f2 (f1

For a superconducting magnet of magnetic resonance imaging (MRI), the novel approach presented in this paper allows the design of cylindrical gradient and shim coils of finite length. The method is based on identification of the weighting of harmonic components in the current distribution that will generate a magnetic field whose z-component follows a chosen spherical harmonic function. Mathematical expressions which relate the harmonic terms in the cylindrical current distribution to spherical harmonic terms in the field expansion are established. Thus a simple matrix inversion approach can be used to design a shim coil of any order pure harmonic. The expressions providing a spherical harmonic decomposition of the field components produced by a particular cylindrical current distribution are novel. A stream function was applied to obtain the discrete wire distribution on the cylindrical-surface. This method does not require the setting of the target-field points. The discussion referring to matrix equations in terms of condition numbers proves that this novel approach has no ill-conditioned problems. The results also indicate that it can be used to design cylindrical-surface shim coils of finite length that will generate a field variation which follows a particular spherical harmonic over a reasonably large-sized volume. [ABSTRACT FROM AUTHOR]

Wang in [1] solved an open problem described by Farin in [2], he constructed a C2 quintic spline interpolation scheme on a refined triangulation. In this paper, we would like to improve Wang's study by enforcing some additional smoothness conditions across the interior edges of Wang's refinement of triangulation Δ. The results imply that our improvement interpolation scheme is more effective than other counterparts. [ABSTRACT FROM AUTHOR]

We construct the fundamental solution of time dependent linear ordinary Dirac system in terms of unknown phase functions. This construction gives approximate representation of solutions which is useful for the study of asymptotic behavior. Introducing analog of Rayleigh quotient for differential equations we generalize Hartman–Wintner asymptotic integration theorems with the error estimates for applications to the Dirac system. We also introduce the adiabatic invariants for the Dirac system, which are similar to the adiabatic invariant of Lorentz’s pendulum. Using a small parameter method it is shown that the change in the adiabatic invariants approaches zero with the power speed as a small parameter approaches zero. As another application we calculate the transition probabilities for the Dirac system. We show that for the special choice of electromagnetic field, the only transition of an electron to the positron with the opposite spin orientation is possible. [ABSTRACT FROM AUTHOR]

Flow-stimulated net K secretion (Jκ) in the cortical collecting duct (CCD) is mediated by an iberiotoxin (IBX)-sensitive BK channel, and requires an increase in intracellular Ca2+ concentration ([Ca2+],). The a-subunit of the reconstituted BK channel is phosphorylated by PKA and PKC. To test whether the BK channel in the native CCD is regulated by these kinases, Jκ and net Na absorption (JNa) were measured at slow (∼1) and fast (∼5 nl·min-1· mm-1) flow rates in rabbit CCDs microperfused in the presence of mPKI, an inhibitor of PKA; calphostin C, which inhibits diacyiglycerol binding proteins, including PKC; or bisindolylmaleimide (BIM) and Gö6976, inhibitors of classic and novel PKC isoforms, added to luminal (L) and/or basolateral (B) solutions. L but not B mPKI increased Jκ in CCDs perfused at a slow flow rate; a subsequent increase in flow rate augmented Jκ modestly. B mPKI alone or with L inhibitor abolished flow stimulation of Jκ. Similarly, L calphostin C increased Jκ in CCDs perfused at slow flow rates, as did calphostin C in both L and B solutions. The observation that IBX inhibited the L mPKI and calphostin C-mediated increases in Jκ at slow flow rates implicated the BK channel in this K flux, a notion suggested by patch-clamp analysis of principal cells. The kinase inhibited by calphostin C was not PKC as L and/or B BIM and Gö6976 failed to enhance Jκ at the slow flow rate. However, addition of these PKC inhibitors to the B solution alone or with L inhibitor blocked flow stimulation of Jκ. Interpretation of these results in light of the effects of these inhibitors on the flow-induced elevation of [Ca2+]i suggests that the principal cell apical BK channel is tonically inhibited by PKA and that flow stimulation of Jκ in the CCD is PKA and PKC dependent. The specific targets of the kinases remain to be identified. [ABSTRACT FROM AUTHOR]

Navigation of cell locomotion by gradients of soluble factors can be desensitized if the concentration of the chemoattractant stays unchanged. It remains obscure if the guidance by immobilized extracellular matrix (ECM) as the substrate is also adaptive and if so, how can the desensitized ECM guidance be resensitized. When first interacting with a substrate containing micron-scale fibronectin (FBN) trails, highly motile fish keratocytes selectively adhere and migrate along the FBN paths. However, such guided motion become adaptive after about 10 min and the cells start to migrate out of the ECM trails. We found that a burst increase of intracellular calcium created by an uncaging technique immediately halts the undirected migration by disrupting the ECM-cytoskeleton coupling, as evidenced by the appearance of retrograde F-actin flow. When the motility later resumes, the activated integrin receptors render the cell selectively binding to the FBN path and reinitiates signaling events, including tyrosine phosphorylation of paxillin, that couple retrograde F-actin flow to the substrate. Thus, the calcium-resensitized cell can undergo a period of ECM-navigated movement, which later becomes desensitized. Our results also suggest that endogenous calcium transients as occur during spontaneous calcium oscillations may exert a cycling resensitization-desensitization control over cell's sensing of substrate guiding cues. [ABSTRACT FROM AUTHOR]