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The development of on-chip nonlinear optical devices in silicon is of great importance to silicon photonics and silicon chip based quantum information processing technologies. With the aim for a viable solution to overcome the lack of second harmonic generation (SHG) in Si, which is fundamentally limited by its centrosymmetric lattice structure, our work investigates SHG behaviors from Si (100) crystals with silver nanostructures formed following deposition of an ultrathin silver film and subsequent annealing. This study is aided by additional techniques, including x-ray photoelectron spectroscopy for measuring surface band bending, secondary electron microscopy for monitoring surface morphology, and Raman scattering for assessing crystal stress. The resultant Ag nanostructures are found to strongly impact the second order nonlinear polarizations in the Si surface regions rather than the bulk. The SHG intensities are increased following the Ag deposition but reduced below the Si control levels after annealing at 600 and 700 °C, which may be due to charge transfer from Ag to SiO2/Si and/or passivation of interfacial defects. Interestingly, annealing at higher temperatures (800 and 900 °C) leads to the formation of Ag nano-shell structures embedded below the SiO2/Si interface, different from the as-deposited and low-temperature annealing cases with Ag nano-spheroid structures appearing on the surface, and concomitantly, the SHG intensities are recovered and even exceed the level for the as-deposited sample in the p-Si case. The enhanced SHG following high-temperature annealing, particularly at 800 °C, is attributed to a redshift of the localized plasmon resonance of these embedded Ag nano-shells relative to the surface-covered nano-spheroids that leads to localized surface plasmon resonance around the fundamental light wavelength. Other factors including electric-field-induced SHG and the effects of stress or oxide thickness can be ruled out. This work suggests a novel approach to enhance second-order optical nonlinearity in Si through the formation of embedded metal nanostructures. [ABSTRACT FROM AUTHOR]

Tackling today's challenges in, e.g., clean energy and climate, manufacturing, sustainability, and bio-preparedness requires novel complex materials with unprecedented control over structure and properties. Applications of XPCS include polymer dynamics in bulk and thin films, colloidal suspensions and gels, domain dynamics in condensed matter systems, surface dynamics during thin film growth or ion bombardment. Figure 1 shows structural dynamics measured by XPCS during fused filament fabrication (FFF) of the thermoplastic polyether ether ketone (PEEK) at the CHX beamline. With state-of-the-art hard X-ray coherent flux and detection systems for fast dynamics, CHX enables researchers to investigate nanoscale and mesoscale dynamics of complex materials on timescales ranging from sub-milliseconds to minutes or hours. [Extracted from the article]

Biological membranes exhibit a great deal of compositional and phase heterogeneity due to hundreds of chemically distinct components. As a result, phase separation processes in cell membranes are extremely difficult to study, especially at the molecular level. It is currently believed that the lateral membrane heterogeneity and the formation of domains, or rafts, are driven by lipid-lipid and lipid-protein interactions. Nevertheless, the underlying mechanisms regulating membrane heterogeneity remain poorly understood. In the present work, we combine inelastic X-ray scattering with molecular dynamics simulations to provide direct evidence for the existence of strongly coupled transient lipid pairs. These lipid pairs manifest themselves experimentally through optical vibrational (a.k.a. phononic) modes observed in binary (1,2-dipalmitoyl-sn-glycero- 3-phosphocholine [DPPC]-cholesterol) and ternary (DPPC-1, 2-dioleoyl-sn-glycero-3-phosphocholine/1-palmitoyl-2-oleoylglycero- 3-phosphocholine [DOPC/POPC]-cholesterol) systems. The existence of a phononic gap in these vibrational modes is a direct result of the finite size of patches formed by these lipid pairs. The observation of lipid pairs provides a spatial (subnanometer) and temporal (subnanosecond) window into the lipid-lipid interactions in complex mixtures of saturated/unsaturated lipids and cholesterol. Our findings represent a step toward understanding the lateral organization and dynamics of membrane domains using a well-validated probe with a high spatial and temporal resolution. [ABSTRACT FROM AUTHOR]

Systematic study on microscopic hydration structure of lithium ion hydrated clusters, [Li(H2O)n]+ (n = 1–20), was carried out by density functional theory (DFT) calculations at ωB97XD/6-311++G(d,p) basis l evel and Car-Parrinello molecular dynamics. The DFT calculation results reveal that the four-coordinated structure is the favorable first hydration sphere for [Li(H2O)n]+ (n = 1–20) clusters in the aqueous phase. The second hydration layer of Li+ is 8 water molecules when n ≥ 12. The energy parameters calculation shows that the structures of the first and second hydration shells are relatively steady. For n > 9, the competitive effects of the second and third hydration layers on water molecules arise and the solvent-solvent interactions for outer hydration shell are strengthened. The results of bond parameters declare that the structure of inner hydration shell has little influence on the H2O molecules of outer hydration layer when the first and second hydration spheres of Li+ are saturated. MD simulation results prove Li+ has a strong first hydration shell with Li–O (I, W) distance of 1.970 Å. Around 8.66 water with Li–O (I, W) distance of 4.10 Å from the second hydration shell. Both DFT and CPMD show Li+ possesses a second hydration shell which is dominantly surrounded by 8 water molecules. [ABSTRACT FROM AUTHOR]

Endothelial cell injury and death precede atherosclerosis development. Thus, it is important to understand the mechanisms that lead to these early changes in endothelial cells. Although members of the MAP kinase/ERK kinase (MEK) kinase 3 (MEKK3)-MEK5-ERK5 module play an essential role in underpinning endothelial cell survival, how they execute these actions remain poorly understood. Furthermore, there is poor understanding of death-inducing pathways in endothelial cells and it is also unclear whether there are direct interactions between the kinase module and death-inducing pathways. Using immunoprecipitation and liquid chromatography-electrospray ionisation tandem mass spectrometry approaches, we show in human umbilical vein endothelial cells that the MEKK3-MEK5-ERK5 ternary complex contains glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a glycolytic enzyme that can trigger the death of certain cell-types. GAPDH binds directly to MEKK3. Interestingly, serum depletion, a trigger of endothelial cell death, results in a rapid loss of cytosolic MEKK3 and MEKK3-GAPDH interaction. MEKK3 rapidly reappears in the cytosol upon serum replenishment, accompanied by the restoration of MEKK3-GAPDH interaction. During serum starvation or exposure to cytotoxic concentrations of H 2 O 2 , GAPDH accumulates in the nucleus. Inhibition of the nuclear accumulation of GAPDH with R-(−)-deprenyl hydrochloride attenuates the degree of cell death. Serum replenishment of serum-starved cells reduces the level of nuclear GAPDH and prevents cell death. Cell-free assays show phosphorylation of GAPDH on four residues by MEKK3. These data not only strongly implicate nuclear GAPDH in causing endothelial cell death but also reveal a potential mechanism for MEKK3 to regulate GAPDH function and hence promote endothelial cell survival. Unlabelled Image • Increases in nuclear GAPDH accompany endothelial cell death • Preventing such increases protects against cell death • MEKK3 binds to and phosphorylates GAPDH • Serum increases MEKK3-GAPDH binding, reduces nuclear GAPDH, promotes cell survival • Serum depletion leads to loss of MEKK3-GAPDH binding and increases nuclear GAPDH [ABSTRACT FROM AUTHOR]

Abstract It has been widely accepted that the thermally excited motions of the molecules in a cell membrane is the prerequisite for a cell to carry its biological functions. On the other hand, the detailed mapping of the ultrafast picosecond single-molecule and the collective lipid dynamics in a cell membrane remains rather elusive. Here, we report all-atom molecular dynamics simulations of a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine bilayer over a wide range of temperature. We elucidate a molecular mechanism underlying the lateral lipid diffusion in a cell membrane across the gel, rippled, and liquid phases using an analysis of the longitudinal and transverse current correlation spectra, the velocity auto-correlation functions, and the molecules mean square displacements. The molecular mechanism is based on the anomalous ultrafast vibrational properties of lipid molecules at the viscous-to-elastic crossover. The macroscopic lipid diffusion coefficients predicted by the proposed diffusion model are in a good agreement with experimentally observed values. Furthermore, we unveil the role of water confined at the water-lipid interface in triggering collective vibrations in a lipid bilayer. Highlights • New model for lateral diffusion in biomembranes has been developed across gel, rippled and liquid phases. • Energy (E) and wavenumber (Q) parameters at the viscous-to-elastic crossover interlink single and collective lipid dynamics, and lipid diffusion. • The single-to-collective picosecond dynamics coupling is shown to play the central role in lateral lipid diffusion. [ABSTRACT FROM AUTHOR]

In the past few decades, there has been a global decrease in dairy cow reproductive performance. An activated inflammatory system, due to uterine infection, has been associated with decreased cow fertility and as such, there is a need to detect uterine disease earlier. Early detection could be achieved by identifying biomarkers for uterine disease. Exosomes are small nanovesicles known to package and deliver protein, mRNA, and miRNAs to near and distant sites. Therefore, the content of circulating exosomes may have the potential to carry biomarkers for earlier diagnosis of disease. We hypothesized that circulating exosomes from cows with and without uterine infection may contain information representative of endometrial health or disease. We compared the proteomic content of circulating exosomes derived from plasma of dairy cows with (n = 10) or without (n = 10) induced uterine infection, using high-performance liquid chromatography tandem mass spectrometry ( HPLC MS/MS ). Our results demonstrate that there were a total of 103 bovine and 9 Trueperella pyogenes proteins found in plasma exosomes derived from infected cows ( infected exosomes ), and 90 bovine and 5 T. pyogenes proteins found in exosomes derived from plasma of non-infected cows ( non-infected exosomes ). 71 bovine proteins were found to be unique to the infected exosomes while only 4 bovine proteins were found to be unique to the non-infected exosomes. 8 unique T. pyogenes proteins were identified in infected exosomes and 4 were found to be unique to the non-infected exosomes. Pathway analysis showed that infected exosomes had more proteins involved in structural molecule activity and immune system processes than non-infected exosomal protein. Additionally, proteins from infected exosomes were involved in unique pathways: angiogenesis and integrin signaling pathway. Our data provide preliminary evidence of a potential role for exosomes in the early diagnosis of uterine infection in dairy cows. [ABSTRACT FROM AUTHOR]

This study investigates the dynamics of riverine DOC concentrations during a series of stream discharge events (3–10 days) following rainstorms of different intensity and duration. We examined six events, when high-frequency (hourly) water samples for DOC (n = 321) were collected in spring (n = 166) and autumn (n = 155). Results identified three distinct water-mediated processes during stream discharges events that linked DOC source supply from agricultural land surfaces with sinks in a receiving river. These were as follows: 1) snowpack drives significant high DOC concentrations in base-flow during spring, 2) abundant organic matter in topsoil from crop residues determines a rapid DOC loading profile in the first flush, and 3) very large hydro-climatic events in snow-melting season over agricultural watersheds could increase the riverine DOC flux by 2.3 folds. These results revealed that ca. 76.5% of annual DOC was exported during a handful of storm-discharge events (78.9% for spring and 74.2% from autumn) over agricultural landscapes. Given the significant amount of riverine DOC exported from agricultural landscapes during severe weather events, our results suggest that changes in climate promote larger precipitation events that would likely enhance the export of terrestrial DOC to receiving water bodies. The study presents a semi-analytical model that is able to extrapolate the riverine DOC dynamics during storm discharge events of varying duration and intensity (R 2 up to 0.9). [ABSTRACT FROM AUTHOR]

A contributing factor to declining fertility in dairy cows is an activated inflammatory system associated with uterine infection. Detecting uterine disease using biomarkers may allow earlier diagnosis and intervention with resultant improvements in fertility. Exosomes are known to participate in intercellular communication, paracrine, and endocrine signaling. Exosomes carry a cargo of proteins, lipids, and nucleic acids that represent specific cellular sources. Prostaglandins are lipids that are critical determinants of bovine fertility. In this study exosomes were isolated from the plasma of cows before (d 0) and during (d 10) the study in healthy animals or those with an induced uterine infection in a 2 × 2 factorial design. Exosomes were characterized for size and number (nanoparticle tracking analysis), exosomal marker expression (Western blot), and morphology (transmission electron microscopy). No significant differences were observed in exosome size or number. The abundance of exosome-enriched markers was confirmed in noninfected and infected animals. Transmission electron microscopy confirmed the morphology of the exosomes. These exosomes were co-incubated with bovine endometrial epithelial and stromal cells. Exosomes from d-10-infected animal plasma decreased PGF2α production in endometrial epithelial but not stromal cells. For future research, the identification of effectors in the cargo may provide a useful basis for early diagnosis of uterine infection using an exosomal characterization approach. [ABSTRACT FROM AUTHOR]

In this paper, an unbalanced plasma enhanced magnetron sputtering system was adopted to deposit four types of the graphite-like carbon (GLC) films under different currents of ion source. The results show that a moderate Ar+bombardment effectively adjusts the content of sp3hybrid structure, and significantly improves the film’s compactness. With the increase of ion source current, the hardness,H/EandH3/E2ratios of the film present a change rule of increasing first and decreasing subsequently, and all achieve their maximum values under the ion source current of 10 A. Moreover, the average values of the studied GLC films are all below 0.05 with slight fluctuation, while the wear rate of the film presents a significant difference with the increase of ion source current. Especially, when the ion source current is 10 A, the friction coefficient and the wear rate of the GLC films are 0.01 and 1.7 × 10−16 m3 N−1 m−1, respectively, presenting excellent tribological properties. [ABSTRACT FROM AUTHOR]

Small crystal Linde Type A (LTA) zeolites were synthesised by a hydrothermal method without any organic additive at different aging temperature for 24 h. The as-synthesised samples were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy. The experimental results showed that the aging temperature was crucial to the crystallinity and morphology of the synthesised zeolite crystals. Samples aged at 30°C presented an average crystal size of 500 nm. [ABSTRACT FROM AUTHOR]

Flood disaster has been one of the most frequent and devastating forms in middle Yellow River, China. Huge flood events transport sediments from upstream to downstream, and lead to changes of river morphology, such as river bed slope, channel roughness, and flood routing process. Flood disasters in the middle Yellow River were constantly caused by backwater effects due to multiple river stream confluence effects. The study aims to investigate confluent flood flow effects on flood routing processes, river morphology, and human activities based on a proposed flood flow model. The proposed model is constructed through coupling hydraulic equations, artificial intelligence neural network and probability theory. Flood frequency analysis is coupled with studies of hydrological routing processes that reduce the flood capacity of the rivers. Flood routing to the confluence were simulated using kinematic wave theory. Case studies have been carried out through field work and model simulation during the past years. Findings are achieved as followings. Firstly, flood frequency at the confluence implies that the confluent extreme flood occurs more frequently in the main streams than that in the tributaries due to influential intensity of East-Asian summer monsoon. Secondly, river morphology was altered partly due to complex flood routing processes in the middle Yellow River under the operation of Sanmenxia Reservoir. The alternated river channels changed the boundary conditions of flood routing, especially for backwater. Bed slopes have greater impacts on flood routing process than roughness does when there is larger flood flow. Finally, the evolution process of the sediment transportation is closely linked with the operations of the Sanmenxia Reservoir. [ABSTRACT FROM AUTHOR]

Host immune responses must be tightly regulated by an intricate balance between positive and negative signals while fighting pathogens; persistent pathogens may usurp these regulatory mechanisms to dampen host immunity to facilitate survival in vivo. Here we report that Tim-3, a negative signalling molecule expressed on monocytes and T cells, is up-regulated on natural killer ( NK) cells in individuals chronically infected with hepatitis C virus ( HCV). Additionally, the transcription factor T-bet was also found to be up-regulated and associated with Tim-3 expression in NK cells during chronic HCV infection. Micro RNA-155 (mi R-155), an mi RNA that inhibits signalling proteins involved in immune responses, was down-regulated in NK cells by HCV infection. This Tim-3/ T-bet over-expression and mi R-155 inhibition were recapitulated in vitro by incubating primary NK cells or NK92 cell line with Huh-7 hepatocytes expressing HCV. Reconstitution of mi R-155 in NK cells from HCV-infected patients led to a decrease in T-bet/ Tim-3 expression and an increase in interferon- γ production. Blocking Tim-3 signalling also enhanced interferon- γ production in NK cells by improving signal transducer and activator of transcription-5 phosphorylation. These data indicate that HCV-induced, mi R-155-regulated Tim-3 expression regulates NK cell function, suggesting a novel mechanism for balancing immune clearance and immune injury during chronic viral infection. [ABSTRACT FROM AUTHOR]

Objective: To determine the effect of lipopolysaccharide (LPS) on NF-κB gene expression and proinflammatory cytokine release from trophoblast cell models, JEG-3 and BeWo human choriocarcinoma cells. Study design: Serum-starved JEG-3 and BeWo cells were treated with LPS (from Escherichia coli serotype 0111:B4) for 24 or 48h. Cell culture medium was collected and assayed for interleukin (IL)-1β, IL-6, IL-8, and transforming necrosis factor (TNF)-α cytokine release using enzyme-linked immunosorbent assays. RNA was extracted from the cells and real-time PCR was performed to measure NF-κB mRNA expression. All results were analyzed by one-way analysis of variance tests followed by Sidak's post hoc analysis. p <0.05 was considered statistically significant. Results: LPS triggered an inflammatory response in JEG-3 cells by inducing a 1.5-fold increase in NF-κB mRNA expression and TNF-α release (0μg/mL: 15.13±2.14, 1μg/mL: 14.94±0.75, 10μg/mL: 23.05±4.50, p <0.05) and a 2-fold elevation in IL-6 secretion (0μg/mL: 12.54±5.44, 1μg/mL: 25.54±0.91, 10μg/mL: 24.28±4.43, p <0.05). In contrast, BeWo cells were not as sensitive to LPS exposure; NF-κB mRNA expression was unchanged between LPS-treated and control cells, whereas a small but significant 1.3-fold increase in TNF-α release was found (TNF-α: 15.45±1.53pg/mL, control: 12.24±1.00pg/mL, p <0.05). The inflammatory pathways in BeWo cells were found to be active given that treatment of these cells with IL-1β and TNF-α induced IL-6 secretion. Interestingly, 1μg/mL LPS appeared to decrease IL-6 and TNF-α release from BeWo cells. IL-1β and IL-8 secretion were not detected from either cell lines. Conclusion: LPS activates the NF-κB pathway in JEG-3 but not BeWo human choriocarcinoma cells and this may be the reason for their differential inflammatory response to LPS exposure. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

Cardiovascular diseases (CVD) are one of the leading causes of death worldwide. Eighty-five percent of CVD-associated deaths are due to heart attacks and stroke. Atherosclerosis leads to heart attack and stroke through a slow progression of lesion formation and luminal narrowing of arteries. Dogs are similar to humans in terms of their cardiovascular physiology, size, and anatomy. Dog models have been developed to recapitulate the complex phenotype of human patients and understand the underlying mechanism of CVD. Different methods, including high-fat, high-cholesterol diet and genetic modification, have been used to generate dog models of human CVD. Remarkably, the location and severity of atherosclerotic lesions in the coronary arteries and branches of the carotid arteries of dog models closely resemble those of human CVD patients. Overt clinical manifestations such as stroke caused by plaque rupture and thrombosis were observed in dog models. Thus, dog models can help define the pathophysiological mechanisms of atherosclerosis and develop potential strategy for preventing and treating CVD. In this review, we summarize the progress in generating and characterizing canine models to investigate CVD and discuss the advantages and limitations of canine CVD models. [ABSTRACT FROM AUTHOR]

We find that the flow of direct electric current (dc) through graphene on substrate enhances surface optical second-harmonic generation (SHG) from the graphene/substrate system. The current can enhance surface SHG by about 300% for a chemical-vapor-deposition (CVD) graphene monolayer on a SiO2/Si(001) substrate, and by about 25% for an epitaxial four-layer-graphene film on a 3.5°-miscut vicinal SiC(0001) substrate. The enhancement in both the CVD and epitaxial graphene samples is due to electric field-induced SHG, which is produced by the current-associated vertical electric field at the SiO2/Si interface or at the graphene/SiC interface. Measurements of rotational-anisotropy SHG (RA-SH) from both samples revealed that the current-induced SHG varies strongly with the measurement location along the current flow direction. By measuring RA-SH from the vicinal SiC(0001) substrate, we determined all three second-order susceptibility tensor elements (d33 = -52.0 pm/V, d15 = 20.0 pm/V, and d31 = 18.7 pm/V) that characterize the SHG response of hexagonal SiC at the fundamental wavelength of 740 nm. We further determined the three effective susceptibility tensor elements (d33 = -135.8 pm/V, d15 = 18.5 pm/V, and d31 = 14.6 pm/V) that characterize the surface SHG from the graphene/vicinal-SiC(0001) sample and finally showed that the current-dependent tensor element d33 can be enhanced to a large value of d33 = -199.0 pm/V by electric current in epitaxial graphene. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate that killer cell lectin-like receptor subfamily G member 1 (KLRG1), a transmembrane protein preferentially expressed on T cells, is highly expressed on CD56+ NK cells, which are significantly reduced in their numbers and functions in the peripheral blood of patients with chronic hepatitis C virus (HCV) infection compared to subjects without infection. KLRG1 expression is also upregulated on healthy NK cells exposed to Huh-7 hepatocytes infected with HCV in vitro. Importantly, the expression levels of KLRG1 are inversely associated with the capacity of NK cells to proliferate and to produce gamma interferon (IFN-γ) but positively associated with apoptosis of NK cells in response to inflammatory cytokine stimulation. KLRG1- NK cells, including CD56bright and CD56dim subsets, exhibit impaired cell activation and IFN-γ production but increased apoptosis compared to KLRG1+ NK cells, particularly in HCV-infected individuals. Importantly, blockade of KLRG1 signaling significantly recovered the impaired IFN-γ production by NK cells from HCV-infected subjects. Blockade of KLRG1 also enhanced the impaired phosphorylation of Akt (Ser473) in NK cells from HCV-infected subjects. Taken together, these results indicate that KLRG1 negatively regulates NK cell numbers and functions via the Akt pathway, thus providing a novel marker and therapeutic target for HCV infection. [ABSTRACT FROM AUTHOR]

Background: Nitrogen uptake and the efficient absorption and metabolism of nitrogen are essential elements in attempts to breed improved cereal cultivars for grain or silage production. One of the enzymes related to nitrogen metabolism is glutamine-2-oxoglutarate amidotransferase (GOGAT). Together with glutamine synthetase (GS), GOGAT maintains the flow of nitrogen from NH4+ into glutamine and glutamate, which are then used for several aminotransferase reactions during amino acid synthesis. Results: The aim of the present work was to identify and analyse the structure of wheat NADH-GOGAT genomic sequences, and study the expression in two durum wheat cultivars characterized by low and high kernel protein content. The genomic sequences of the three homoeologous A, B and D NADH-GOGAT genes were obtained for hexaploid Triticum aestivum and the tetraploid A and B genes of Triticum turgidum ssp. durum. Analysis of the gene sequences indicates that all wheat NADH-GOGAT genes are composed of 22 exons and 21 introns. The three hexaploid wheat homoeologous genes have high conservation of sequence except intron 13 which shows differences in both length and sequence. A comparative analysis of sequences among di- and mono-cotyledonous plants shows both regions of high conservation and of divergence. qRT-PCR performed with the two durum wheat cvs Svevo and Ciccio (characterized by high and low protein content, respectively) indicates different expression levels of the two NADH-GOGAT-3A and NADH-GOGAT-3B genes. Conclusion: The three hexaploid wheat homoeologous NADH-GOGAT gene sequences are highly conserved – consistent with the key metabolic role of this gene. However, the dicot and monocot amino acid sequences show distinctive patterns, particularly in the transit peptide, the exon 16–17 junction, and the C-terminus. The lack of conservation in the transit peptide may indicate subcellular differences between the two plant divisions - while the sequence conservation within enzyme functional domains remains high. Higher expression levels of NADH-GOGAT are associated with higher grain protein content in two durum wheats. [ABSTRACT FROM AUTHOR]

Abstract: Establishing a link between the optical and biogeochemical properties of near-shore waters continues to be a challenge for both riverine and estuarine areas worldwide due to terrestrial influences. This study aimed to evaluate the effectiveness of an inversion algorithm for the extraction of riverine and estuarine CDOM properties at global scales. Our CDOM evaluation focused on five aspects: 1) the range of worldwide CDOM levels, 2) spatial distribution patterns, (3) climatic influences, (4) influences of land cover change, and (5) seasonal effects. The study locations consisted of the estuarine and coastal regions of 10 major rivers spread across five continents. Our approach was to examine the QAA-CDOM algorithm by extracting CDOM properties from hundreds of EO-1 Hyperion images acquired during the last decade (2001–2011). Preliminary results showed that CDOM absorption coefficients at 440nm within the 10 selected rivers exhibited a broad range (0.02–7.2m−1). Spatial CDOM distribution patterns showed many plumes dispersing from source areas (e.g. adjacent terrestrial vegetated areas) along the direction of flow. Seasonal variations in CDOM levels are also evident (i.e. 0.5–4.0m−1) as illustrated by the January, April, August and October images of the Volga River. CDOM levels also appeared to trend upward with the increase in forest coverage (i.e. terrestrial influence) within the watersheds studied over the last decade. Our results strongly suggest that the algorithm is effective in distinguishing riverine and estuarine CDOM levels affected by factors such as global biogeography, climate conditions and regional land surface processes. [Copyright &y& Elsevier]

The current limitations in genome sequencing technology require the construction of physical maps for high-quality draft sequences of large plant genomes, such as that of Aegilops tauschii, the wheat D-genome progenitor. To construct a physical map of the Ae. tauschii genome, we fingerprinted 461,706 bacterial artificial chromosome clones, assembled contigs, designed a 10K Ae. tauschii Infinium SNP array, constructed a 7,185-marker genetic map, and anchored on the map contigs totaling 4.03 Gb. Using whole genome shotgun reads, we extended the SNP marker sequences and found 17,093 genes and gene fragments. We showed that collinearity of the Ae. tauschii genes with Brachypodium distachyon, rice, and sorghum decreased with phylogenetic distance and that structural genome evolution rates have been high across all investigated lineages in subfamily Pooideae, including that of Brachypodieae. We obtained additional information about the evolution of the seven Triticeae chromosomes from 12 ancestral chromosomes and uncovered a pattern of centromere inactivation accompanying nested chromosome insertions in grasses. We showed that the density of noncollinear genes along the Ae. tauschii chromosomes positively correlates with recombination rates, suggested a cause, and showed that new genes, exemplified by disease resistance genes, are preferentially located in high-recombination chromosome regions. [ABSTRACT FROM AUTHOR]

We find that optical second-harmonicgeneration (SHG) in reflectionfrom a chemical-vapor-deposition graphene monolayer transferred ontoa SiO2/Si(001) substrate is enhanced about 3 times by theflow of direct current electric current in graphene. Measurementsof rotational-anisotropy SHG revealed that the current-induced SHGfrom the current-biased graphene/SiO2/Si(001) structureundergoes a phase inversion as the measurement location on grapheneis shifted laterally along the current flow direction. The enhancementis due to current-associated charge trapping at the graphene/SiO2interface, which introduces a vertical electric field acrossthe SiO2/Si interface that produces electric field-inducedSHG. The phase inversion is due to the positive-to-negative polarityswitch in the current direction of the trapped charges at the current-biasedgraphene/SiO2interface. [ABSTRACT FROM AUTHOR]

Abstract: This study aims to understand the influences of climate change and land surface processes on the variation of in-stream DOC concentrations in coastal rivers crossing different climate zones. Monthly observations spanning multiple years in seven major rivers in four different climate zones within the U.S. were analyzed for correlations between dissolved organic carbon (DOC) concentration and surface air temperature, precipitation, land cover and discharge. The major watersheds were the Altamaha River (GA), the Apilachicola River (FL), the Columbia River (OR), the Delaware River (NJ), the Sacramento and San Joaquin Rivers (CA) and the Susquehanna River (MD). One minor watershed, the Neponset River (MA) was also analyzed. Results indicate that temperature is the most important variable for DOC export when the variation of annual mean temperatures is large (e.g., >5°C) with sufficient precipitation levels. Land-surface characteristics and discharges are better correlated to DOC concentrations when the variations of annual mean temperatures are small (e.g. <2°C). However, results from the small watershed (Neponset) showed that land surface processes can vary annual DOC concentrations about ±1.65mg/L from mean value. This study is the first to examine DOC relationships in watersheds in multiple climate zones, and it was determined that weak correlations between temperature and DOC found in previous studies may be attributable to the fact that those studies examined small watersheds contained within a single climate zone. DOC flux per square meter was calculated based on incremental temperature increases. The results indicate that an increase of 1°C would result in a 0.476mg/L increase of in-stream DOC in large watersheds. Climate warming would have a greater impact on riverine DOC yields in cooler climate zones (up to 26% per °C) than on those in warmer climate zones (up to 6% per °C). [Copyright &y& Elsevier]

Optical second-harmonic generation (SHG) from Si surfaces covered with nanometer-thin SiO2 varies with the laser exposure time because of photo-injection and charge trapping. We use UV lamp excitation to decompose the effects of photo-injection and charge trapping on the time-dependence of SHG of 1.65 eV photons at the Si/SiO2 interface. We find that the time-dependence of SHG in air arises mainly from the cooperative effect of three-photon photo-injection and charge trapping by surface O2. When the oxide is ultrathin (≤1.5 nm), the time-dependence also includes a significant contribution from one and two-photon photo-assisted tunneling. [ABSTRACT FROM AUTHOR]

An accurate single-sheeted double many-body expansion potential energy surface (PES) is reported for the title system, which is suitable for dynamics and kinetics studies of the reactions N(2 D) + H2( X1 Σ [ABSTRACT FROM AUTHOR]

Abstract: The role of lipid metabolism has gained particular interest in prostate cancer research. A large body of literature has outlined the unique upregulation of de novo lipid synthesis in prostate cancer. Concordant with this lipogenic phenotype is a metabolic shift, in which cancer cells use alternative enzymes and pathways to facilitate the production of fatty acids. These newly synthesized lipids may support a number of cellular processes to promote cancer cell proliferation and survival. Hence, de novo lipogenesis is under intense investigation as a therapeutic target. Epidemiologic studies suggest dietary fat may also contribute to prostate cancer; however, whether dietary lipids and de novo synthesized lipids are differentially metabolized remains unclear. Here, we highlight the lipogenic nature of prostate cancer, especially the promotion of de novo lipid synthesis, and the significance of various dietary lipids in prostate cancer development and progression. [Copyright &y& Elsevier]

Abstract: The origin, function, and fate of dissolved organic carbon (DOC) in stream flow are not well-understood. This study explores the environmental factors controlling the spatial and temporal variation of DOC in terrestrial ecosystems of a watershed southeast of Boston, Massachusetts. Our hypothesis is that environmental factors: stream flow, land cover type, vegetation density, and drainage area are significant in estimating DOC export from an urban watershed. The hypothesized environmental factors were statistically correlated to the variation of the sampled in-stream DOC concentrations at annual, seasonal, and daily scales. For the purpose of scaling up to a large watershed that lacks dense gauged hydrological data or for projection of future scenarios, we examined the effectiveness of using simulated stream flow for studying terrestrial DOC dynamics. Our results demonstrated that all hypothesized environmental factors except vegetation density were particularly strong predictors in watersheds with a large proportion of developed (urban) area. The resulting linear model is able to explain about 76% (R 2 =0.76) and 64% (R 2 =0.64) of the variance of in-stream DOC concentrations at seasonal and annual scales respectively. Results suggest that more frequent DOC sampling than once each month is required to establish the quantitative relationship between simulated stream flows from a Soil Water Assessment Tool (SWAT) and in-stream DOC concentrations at daily scale. Using a hydrological model is effective for studying the impacts of climate and human activities on DOC export to aquatic ecosystems at appropriate scales. [Copyright &y& Elsevier]

1. This study evaluates the efficacy of remote sensing technology to monitor species composition, areal extent and density of aquatic plants (macrophytes and filamentous algae) in impoundments where their presence may violate water-quality standards. 2. Multispectral satellite (IKONOS) images and more than 500 in situ hyperspectral samples were acquired to map aquatic plant distributions. By analyzing field measurements, we created a library of hyperspectral signatures for a variety of aquatic plant species, associations and densities. We also used three vegetation indices. Normalized Difference Vegetation Index (NDVI), near-infrared (NIR)-Green Angle Index (NGAI) and normalized water absorption depth ( DH), at wavelengths 554, 680, 820 and 977 nm to differentiate among aquatic plant species composition, areal density and thickness in cases where hyperspectral analysis yielded potentially ambiguous interpretations. 3. We compared the NDVI derived from IKONOS imagery with the in situ, hyperspectral-derived NDVI. The IKONOS-based images were also compared to data obtained through routine visual observations. Our results confirmed that aquatic species composition alters spectral signatures and affects the accuracy of remote sensing of aquatic plant density. The results also demonstrated that the NGAI has apparent advantages in estimating density over the NDVI and the DH. 4. In the feature space of the three indices, 3D scatter plot analysis revealed that hyperspectral data can differentiate several aquatic plant associations. High-resolution multispectral imagery provided useful information to distinguish among biophysical aquatic plant characteristics. Classification analysis indicated that using satellite imagery to assess Lemna coverage yielded an overall agreement of 79% with visual observations and >90% agreement for the densest aquatic plant coverages. 5. Interpretation of biophysical parameters derived from high-resolution satellite or airborne imagery should prove to be a valuable approach for assessing the effectiveness of management practices for controlling aquatic plant growth in inland waters, as well as for routine monitoring of aquatic plants in lakes and suitable lentic environments. [ABSTRACT FROM AUTHOR]

A survey and analysis is made of all available ω-gliadin DNA sequences including ω-gliadin genes within a large genomic clone, previously reported gene sequences, and ESTs identified from the large wheat EST collection. A contiguous portion of the Gli-B3 locus is shown to contain two apparently active ω-gliadin genes, two pseudogenes, and four fragments of the 3′ portion of ω-gliadin sequences. Comparison of ω-gliadin sequences allows a phylogenetic picture of their relationships and genomes of origin. Results show three groupings of ω-gliadin active gene sequences assigned to each of the three hexaploid wheat genomes, and a fourth group thus far consisting of pseudogenes assigned to the A-genome. Analysis of ω-gliadin ESTs allows reconstruction of two full-length model sequences encoding the AREL- and ARQL-type proteins from the Gli-A3 and Gli-D3 loci, respectively. There is no DNA evidence of multiple active genes from these two loci. In contrast, ESTs allow identification of at least three to four distinct active genes at the Gli-B3 locus of some cultivars. Additional results include more information on the position of cysteines in some ω-gliadin genes and discussion of problems in studying the ω-gliadin gene family. [ABSTRACT FROM AUTHOR]

Background: Brachypodium distachyon (Brachypodium) has been recognized as a new model species for comparative and functional genomics of cereal and bioenergy crops because it possesses many biological attributes desirable in a model, such as a small genome size, short stature, self-pollinating habit, and short generation cycle. To maximize the utility of Brachypodium as a model for basic and applied research it is necessary to develop genomic resources for it. A BAC-based physical map is one of them. A physical map will facilitate analysis of genome structure, comparative genomics, and assembly of the entire genome sequence. Results: A total of 67,151 Brachypodium BAC clones were fingerprinted with the SNaPshot HICF fingerprinting method and a genome-wide physical map of the Brachypodium genome was constructed. The map consisted of 671 contigs and 2,161 clones remained as singletons. The contigs and singletons spanned 414 Mb. A total of 13,970 gene-related sequences were detected in the BAC end sequences (BES). These gene tags aligned 345 contigs with 336 Mb of rice genome sequence, showing that Brachypodium and rice genomes are generally highly colinear. Divergent regions were mainly in the rice centromeric regions. A dot-plot of Brachypodium contigs against the rice genome sequences revealed remnants of the whole-genome duplication caused by paleotetraploidy, which were previously found in rice and sorghum. Brachypodium contigs were anchored to the wheat deletion bin maps with the BES gene-tags, opening the door to Brachypodium-Triticeae comparative genomics. Conclusion: The construction of the Brachypodium physical map, and its comparison with the rice genome sequence demonstrated the utility of the SNaPshot-HICF method in the construction of BAC-based physical maps. The map represents an important genomic resource for the completion of Brachypodium genome sequence and grass comparative genomics. A draft of the physical map and its comparisons with rice and wheat are available at http://phymap.ucdavis.edu/brachypodium/. [ABSTRACT FROM AUTHOR]

Inelastic X-ray scattering (IXS) is a powerful technique capable of probing the dynamic behavior and electronic structure of materials. For IXS experiments under high pressure up to the megabar range using state-of-the-art diamond- anvil-cell technology, the sample volume is limited to the order of 1 x iO~ mm3 for which a beam focus of the same order and less is often required. In this paper a scheme utilizing a set of low-cost and compact Kirkpatrick-B aez mirrors for upgrading the existing optical system of the Taiwan IXS beamline at SPring-8 is described. The scheme as implemented improves the focus to 13 jim x 16 pm (horizOntal x vertical) with a transmission of up to 72% and a flux density gain of over 30 times, which has enhanced substantially the efficiency of the beamline for high-pressure research. [ABSTRACT FROM AUTHOR]

Brachypodium is well suited as a model system for temperate grasses because of its compact genome and a range of biological features. In an effort to develop resources for genome research in this emerging model species, we constructed 2 bacterial artificial chromosome (BAC) libraries from an inbred diploid Brachypodium distachyon line, Bd21, using restriction enzymes HindIII and BamHI. A total of 73 728 clones (36 864 per BAC library) were picked and arrayed in 192 384-well plates. The average insert size for the BamHI and HindIII libraries is estimated to be 100 and 105 kb, respectively, and inserts of chloroplast origin account for 4.4% and 2.4%, respectively. The libraries individually represent 9.4- and 9.9-fold haploid genome equivalents with combined 19.3-fold genome coverage, based on a genome size of 355 Mb reported for the diploid Brachypodium, implying a 99.99% probability that any given specific sequence will be present in each library. Hybridization of the libraries with 8 starch biosynthesis genes was used to empirically evaluate this theoretical genome coverage; the frequency at which these genes were present in the library clones gave an estimated coverage of 11.6- and 19.6-fold genome equivalents. To obtain a first view of the sequence composition of the Brachypodium genome, 2185 BAC end sequences (BES) representing 1.3 Mb of random genomic sequence were compared with the NCBI GenBank database and the GIRI repeat database. Using a cutoff expectation value of E  × 10-10, only 3.3% of the BESs showed similarity to repetitive sequences in the existing database, whereas 40.0% had matches to the sequences in the EST database, suggesting that a considerable portion of the Brachypodium genome is likely transcribed. When the BESs were compared with individual EST databases, more matches hit wheat than maize, although their EST collections are of a similar size, further supporting the close relationship between Brachypodium and the Triticeae. Moreover, 122 BESs have significant matches to wheat ESTs mapped to individual chromosome bin positions. These BACs represent colinear regions containing the mapped wheat ESTs and would be useful in identifying additional markers for specific wheat chromosome regions. [ABSTRACT FROM AUTHOR]

Fragile X syndrome (FraX) is the most common inherited mental retardation disease. It is caused by mutation of the fragile X mental retardation 1 (fmr1) gene. The FMR1 protein (FMRP) is a widely expressed RNA-binding translational regulator with reportedly hundreds of potential targets. Recent work has focused on putative roles of FMRP in regulating the development and plasticity of neuronal synaptic connections. The newest animal model of FraX, the fruit fly Drosophila, has revealed several novel mechanistic insights into the disease. This review focuses on Drosophila FMRP as (i) a negative regulator of translation via noncoding RNA, including microRNA and adaptor BC1 RNA-mediated silencing mechanisms; (ii) a negative regulator of microtubule cytoskeleton stability; and (iii) a negative regulator of neuronal architectural complexity. [Copyright &y& Elsevier]

Fragile X Syndrome (FraX) is the most common form of inherited mental retardation. The disease is caused by the silencing of the fragile X mental retardation 1 (fmr1) gene, which encodes the RNA binding translational regulator FMRP . In FraX patients and fmr1 knockout mice, loss of FMRP causes denser and morphologically altered postsynaptic dendritic spines . Previously, we established a Drosophila FraX model and showed that dFMRP acts as a negative translational regulator of Futsch/MAP1B and negatively regulates synaptic branching and structural elaboration in the peripheral neuromuscular junction (NMJ) . Here, we investigate the role of dFMRP in the central brain, focusing on the mushroom body (MB), the learning and memory center . In MB neurons, dFMRP bidirectionally regulates multiple levels of structural architecture, including process formation from the soma, dendritic elaboration, axonal branching, and synaptogenesis. Drosophila fmr1 (dfmr) null mutant neurons display more complex architecture, including overgrowth, overbranching, and abnormal synapse formation. In contrast, dFMRP overexpression simplifies neuronal structure, causing undergrowth, underbranching, and loss of synapse differentiation. Studies of ultrastructural dfmr mutant neurons reveal enlarged and irregular synaptic boutons with dense accumulation of synaptic vesicles. Taken together, these data show that dFMRP is a potent negative regulator of neuronal architecture and synaptic differentiation in both peripheral and central nervous systems. [Copyright &y& Elsevier]

Macroorchidism (i.e., enlarged testicles) and mental retardation are the two hallmark symptoms of Fragile X syndrome (FraX). The disease is caused by loss of fragile X mental retardation protein (FMRP), an RNA-binding translational regulator. We previously established a FraX model in Drosophila, showing that the fly FMRP homologue, dFXR, acts as a negative translational regulator of microtubule-associated Futsch to control stability of the microtubule cytoskeleton during nervous system development. Here, we investigate dFXR function in the testes. Male dfxr null mutants have the enlarged testes characteristic of the disease and are nearly sterile (>90% reduced male fecundity). dFXR protein is highly enriched in Drosophila testes, particularly in spermatogenic cells during the early stages of spermatogenesis. Cytological analyses reveal that spermatogenesis is arrested specifically in late-stage spermatid differentiation following individualization. Ultrastructurally, dfxr mutants lose specifically the central pair microtubules in the sperm tail axoneme. The frequency of central pair microtubule loss becomes progressively greater as spermatogenesis progresses, suggesting that dFXR regulates microtubule stability. Proteomic analyses reveal that chaperones Hsp60B-, Hsp68-, Hsp90-related protein TRAP1, and other proteins have altered expression in dfxr mutant testes. Taken together with our previous nervous system results, these data suggest a common model in which dFXR regulates microtubule stability in both synaptogenesis in the nervous system and spermatogenesis in the testes. The characterization of dfxr function in the testes paves the way to genetic screens for modifiers of dfxr-induced male sterility, as a means to efficiently dissect FMRP-mediated mechanisms. [Copyright &y& Elsevier]

This paper presents a preliminary research result of spatially quantifying and allocating the potential activity of residential wood burning (RWB) by using demographic, hypsographic, climatic and topographic information as independent variables. We also introduce the method for calculating PM2.5 emission from residential wood combustion with the potential activity as primary variable. A linear regression model was generated to describe spatial and temporal distribution of the potential activity of wood burning as primary heating source. In order to improve the estimation, the classifications of urban, suburban and rural were redefined to meet the specifications of this application. Also, a unique way of defining forest accessibility is found useful in estimating the activity potential of RWB. The results suggest that the potential activity of wood burning is mostly determined by elevation of a location, forest accessibility, urban/non-urban position, climatic conditions and several demographic variables. The analysis results were validated using survey data collected through face-to-face and telephone interviews over the study area in central California. The linear regression model can explain approximately 86% of the variation of surveyed wood burning activity potential. The total PM2.5 emitted from woodstoves and fireplaces is analyzed for the study region at county level. [Copyright &y& Elsevier]

Secretion of noradrenaline from large dense-core vesicles in chromaffin cells involves both rapid and slow components of exocytosis which are differentially sensitive to changes in external calcium, osmotic pressure and interruption of the interacting SNARE proteins. Electrical signs of secretion of ATP from sympathetic nerve terminals of mouse vas deferens, the excitatory junctional currents (EJCs), also indicate both rapid and slow mechanisms of exocytosis, which might also show such differential sensitivity. We report here that the large and fast EJCs are highly sensitive to changes in extracellular calcium ions whereas the small and slow EJCs are not. Furthermore, the frequency of fast EJCs is accelerated by hypotonic solutions whereas the slow EJCs are accelerated by hypertonic solution. Fast EJCs, but not slow EJCs, are blocked by peptide fragments of α-SNAP and syntaxin whereas slow EJCs are not. These observations point to two classes of exocytosis from sympathetic nerve terminals that parallel those of exocytosis from chromaffin cells. [Copyright &y& Elsevier]

The sec6/8, or exocyst, complex is implicated in trafficking of secretory vesicles to fusion sites in the plasma membrane. Genetic analyses have been done primarily in yeast, where mutation of the eight protein subunits similarly disrupts polarized vesicle fusion. The goal of this study was to assay the sec6/8 complex in Drosophila , and specifically to test its widely hypothesized functions in synaptogenesis and neurotransmission. We used a transgenic RNAi approach to remove the most highly conserved complex component, Drosophila sec10 (dSec10). Ubiquitous dSec10 RNAi resulted in early postembryonic lethality, demonstrating that dSec10 is essential. Surprisingly, tissue-specific dSec10 RNAi revealed no essential requirement in nervous system, musculature, gut or epidermis. Assays of polarized secretion in all these tissues failed to reveal any role for dSec10. In particular, the neuromuscular synapse showed no defects in morphogenesis or vesicle trafficking/fusion underlying neurotransmission. The essential requirement for dSec10 was restricted to the ring gland, the Drosophila organ specialized for endocrine function. The developmental arrest of dSec10 RNAi animals was partially rescued by feeding ecdysone, suggesting dSec10 mediates steroid hormone secretion. We conclude that dSec10 has no detectable role in most forms of polarized trafficking/exocytosis, including neurotransmission, but rather is essential for endocrine secretion . [ABSTRACT FROM AUTHOR]

Examines the fragile X mental retardation gene (FMR1) in Drosophila species. Presence of synaptic structural defects; Association of immunoprecipitation in FMR1 homolog (dfxr) and futsch messenger RNA; Role of dFXR as a translational repressor of Futsch.

Key message: Eleven wheat lines that are missing genes for the 1D-encoded omega-5 gliadins will facilitate breeding efforts to reduce the immunogenic potential of wheat flour for patients susceptible to wheat allergy. Efforts to reduce the levels of allergens in wheat flour that cause wheat-dependent exercise-induced anaphylaxis are complicated by the presence of genes encoding omega-5 gliadins on both chromosomes 1B and 1D of hexaploid wheat. In this study, we screened 665 wheat germplasm samples using gene specific DNA markers for omega-5 gliadins encoded by the genes on 1D chromosome that were obtained from the reference wheat Chinese Spring. Eleven wheat lines missing the PCR product corresponding to 1D omega-5 gliadin gene sequences were identified. Two of the lines contained the 1BL·1RS translocation. Relative quantification of gene copy numbers by qPCR revealed that copy numbers of 1D omega-5 gliadins in the other nine lines were comparable to those in 1D null lines of Chinese Spring, while copy numbers of 1B omega-5 gliadins were like those of Chinese Spring. 2-D immunoblot analysis of total flour proteins from the selected lines using a specific monoclonal antibody against the N-terminal sequence of omega-5 gliadin showed no reactivity in regions of the blots containing previously identified 1D omega-5 gliadins. Interestingly, RP-UPLC analysis of the gliadin fractions of the selected lines indicated that the expression of omega-1,2 gliadins was also significantly reduced in seven of the lines, implying that 1D omega-5 gliadin and 1D omega-1,2 gliadin genes are tightly linked on the Gli-D1 loci of chromosome 1D. Wheat lines missing the omega-5 gliadins encoded by the genes on 1D chromosome should be useful in future breeding efforts to reduce the immunogenic potential of wheat flour. [ABSTRACT FROM AUTHOR]

Post-translational modifications regulate diverse activities of a colossal number of proteins. For example, various types of lipids can be covalently linked to proteins enzymatically or non-enzymatically. Protein lipidation is perhaps not as extensively studied as protein phosphorylation, ubiquitination, or glycosylation although it is no less significant than these modifications. Evidence suggests that proteins can be attached by at least seven types of lipids, including fatty acids, lipoic acids, isoprenoids, sterols, phospholipids, glycosylphosphatidylinositol anchors, and lipid-derived electrophiles. In this review, we summarize types of protein lipidation and methods used for their detection, with an emphasis on the conjugation of proteins with polyunsaturated fatty acids (PUFAs). We discuss possible reasons for the scarcity of reports on PUFA-modified proteins, limitations in current methodology, and potential approaches in detecting PUFA modifications. [ABSTRACT FROM AUTHOR]

Dogs interact with humans effectively and intimately. However, the neural underpinnings for such interspecies social communication are not understood. It is known that interbrain activity coupling, i.e., the synchronization of neural activity between individuals, represents the neural basis of social interactions. Here, previously unknown cross‐species interbrain activity coupling in interacting human–dog dyads is reported. By analyzing electroencephalography signals from both dogs and humans, it is found that mutual gaze and petting induce interbrain synchronization in the frontal and parietal regions of the human–dog dyads, respectively. The strength of the synchronization increases with growing familiarity of the human–dog dyad over five days, and the information flow analysis suggests that the human is the leader while the dog is the follower during human–dog interactions. Furthermore, dogs with Shank3 mutations, which represent a promising complementary animal model of autism spectrum disorders (ASD), show a loss of interbrain coupling and reduced attention during human–dog interactions. Such abnormalities are rescued by the psychedelic lysergic acid diethylamide (LSD). The results reveal previously unknown interbrain synchronizations within an interacting human–dog dyad which may underlie the interspecies communication, and suggest a potential of LSD for the amelioration of social impairment in patients with ASD. [ABSTRACT FROM AUTHOR]

Studies the relationship between the adenine nucleotide translocase gene in Drosophilia melanogaster. Encoding of adenine nucleotide translocase by the sesB; No effect of sesB transformants to interspecific hybrid viability.

The Deleted in Colorectal Cancer gene (DCC) encodes a cell surface receptor that belongs to the Ig superfamily. Inactivation of the DCC gene has been implicated in human tumor progression. However, little is known about the biological function of the DCC protein. In the present study, we demonstrated that expression of DCC activated caspase-3 and programmed cell death, or induced G2/M cell cycle arrest in tumor cells. In some cell lines, apoptosis was evident within 24 h of DCC expression. Timing of the appearance of apoptotic cells coincided with that of the cleavage of poly (ADP-ribose) polymerase, a substrate of caspase-3. Expression of the apoptosis inhibitory gene Bcl-2 was not able to abrogate the DCC-induced apoptosis. In the G2/M cycle arrest cells, cdk1 activity was inhibited. Our results suggest that the DCC protein may transduce signals resulting in activation of caspases or inhibition of Cdk1. These data provide a possible mechanism by which DCC suppresses tumorigenesis. [ABSTRACT FROM AUTHOR]

Postulated roles for p21Waf1/Cip1/Sdi1 (p21) in DNA repair and apoptosis remain controversial. Studies suggest both stimulatory and inhibitory effects of p21 in DNA repair. p21 has also been implicated in induction or protection from apoptosis. Using the tetracycline inducible expression system, we studied the role of p21 in DNA repair and apoptosis in wild-type p53 deficient DLD1 colorectal carcinoma cells. These cells displayed marked heterogeneity in their ability to tolerate higher levels of exogenous p21. The majority of the p21 overexpressing cells grew slower and did not exhibit apoptotic phenotype, some cells underwent apoptotic death within 5 – 8 days following p21 induction while other became giant cells prior to undergoing cell death. Induction of p21 transgene neither sensitized to nor protected from adriamycin-induced acute cell death. p21 also did not alter the clonogenic survival following adriamycin treatment. Clonogenic survival after u.v.-irradiation was, however, increased when p21 expression was transiently induced a few hours before and after u.v.-irradiation. Consistent with its effect on clonogenic survival, p21 also enhanced the cellular capacity to repair three different exogenously introduced u.v.-damaged reporter plasmids. Taken together our results demonstrate that p21 may modulate the nucleotide excision repair process to facilitate the repair of u.v.-type DNA damage even in the absence of wild-type p53. [ABSTRACT FROM AUTHOR]

TGF-β is a potent growth inhibitor of epithelial cells. However, many transformed cells have lost their sensitivity to this growth inhibitory effect. The molecular mechanism of such insensitivity is not yet understood. Here, we have studied the TGF-β1 effect on normal human prostate and carcinoma cells. Our results showed that normal cells were sensitive to growth inhibition, whereas tumor cells were not or only minimally inhibited regardless of the concentration of TGF-β1 (20 to 80 pM) or time of exposure (1–5 days). p21WAF1/Cip1/Sdi1 and p15INK4B but not p27KIP1 were detectable by Western blotting in normal and tumor cells. TGF-β1 treatment increased the association of p21WAF1/Cip1/Sdi1 with the Cdk2/cyclin E complex in both normal and prostate tumor cells. However, there was no increase in the association of p15INK4B nor p27Kip1 with the Cdk/cyclin complexes. In normal cells, the increase in the association of p21WAF1/Cip1/Sdi1. With the Cdk2/cyclin E complex resulted in inhibition of the Cdk2 activity. In contrast, although there was an increase in the association of p21WAF1/Cip1/Sdi1 with the Cdk2/cyclin E complex in tumor cells, there was no inhibition of the Cdk2 activity. These results indicate that a lack of inhibition of the Cdk2 activity correlates with insensitivity to TGF-β1 in prostate tumor cells. [ABSTRACT FROM AUTHOR]

We report here the Raman spectra of NADPH, NADP. 3-acetylpyridine adenine dinucleotide (AcPdADP), NADH and a fragment of these molecules, 2′-phospho-adenosine-5′-diphosphoribose (Ado2′p5′ppRib), bound to Escherichia coli dihydrofolate reductase (DHFR). The positions that are observed for the bound adenosine ‘triplet‘ bands are consistent with a protein binding pocket for this group which is quite hydrophobic in nature. No binding effect is observed on Raman bands associated with the nicotinamide group of NADP as a binary complex with DHFR. Suggesting very loose, if any, binding of this group. In contrast, changes in the Raman spectrum of the nicotin-amide group of NADP bound to an inhibitor (trimethoprim) ternary complex of DHFR are clearly observed which indicate substantial binding interaction. The carboxamide group of bound NADPH (and NADH) adopts the trans conformation. A 35-cm¹ upshift is observed in the rocking motion of the carboxamide-NH2 group of NADPH, and a 5-cm¹ upward shift is seen in the C=O stretch mode of AcPdADP¹ upon binding to the enzyme-trimethoprim complex. These results suggest that the -NH2 group of the carboxamide moiety is more tightly hydrogen bonded in the protein binding pocket than in solution while that of the C=O group is less tightly hydrogen bonded; these hydrogen bonds would appear to be responsible for holding the nicotinamide headgroup in place properly for catalysis. We have compared this with the results obtained previously in other protein complexes, and interpret the observed shifts in these bands as a measure of the hydrogen bonding enthalpy of the -NH2 and C=O groups with their protein environments. Perhaps surprisingly, the magnitude of the hydrogen bonding enthalpy takes on a limited number of discrete values over five protein complexes rather than over a continuous range. The effect that this has on the catalytic properties of DHFR and the other NAD dehydrogenases that we have studied to date, particularly their stereo-chemistry, is discussed. A small downward shift is observed for the P [This symbol cannot be presented into ASCII text] O stretch of the 2′-phosphate moiety of NADP. This indicates that the 2′-phosphate moiety binds to DHFR in the dianionic form. Futhermore, the local enthalpic interaction that the 2′-phosphate group has with protein is stronger than its interaction with water. [ABSTRACT FROM AUTHOR]

Abstract: Silicon nanoparticles on fused silica have potential as recombination centers in infrared detectors due quantum confinement effects that result in a size dependent band gap. Growth on fused silica was realized by etching in HF, annealing under vacuum at 700–750 °C, and cooling to ambient temperature before ramping to the growth temperature of 600 °C. Silicon particles could not be grown in a thermal chemical vapor deposition (CVD) process with adequate size uniformity and density. Seeding fused silica with Si adatoms in a hot-wire chemical vapor deposition (HWCVD) process at a disilane pressure of 1.1×10−5 Pa followed by thermal CVD at a disilane pressure of 1.3×10−2 Pa, or direct HWCVD at a disilane pressure of 2.1×10−5 Pa led to acceptable size uniformity and density. Dangling bonds at the surface of the as-grown nanoparticle were passivated using atomic H formed by cracking H2 over the HWCVD filament. [Copyright &y& Elsevier]

A properly performed amputation can not only be lifesaving for the patient, but may often be a better therapeutic alternative than an ill-conceived, futile attempt at a vascular reconstruction doomed to fail for lack of adequate recipient vessels. Currently there are no consistent criteria that can be applied before surgery. The purpose of the present investigation was to find a reliable method of determining the best amputation level in an ischaemic lower extremity. In the present study the author has tried to devise a ‘score’ for distal run-off vessel patency as shown by the preoperative angiogram to determine the most appropriate amputation level. The author has reviewed the level of amputation on ischaemic lower extremities in the vascular surgery unit of the Austin and Repatriation Medical Centre (ARMC) over the last 5 years. Two hundred and two patients have undergone 232 lower extremity amputations at ARMC. The author used χ2 corrected testing and found a good correlation between the score and the level of amputation. The lower the score, the higher the level of amputations (χ2 = 289.23, P < 0.005). The author could predict that with a score of <12 a patient would probably need an above-knee amputation; for a score from 12 to 19, a below-knee amputation; for a score of 20−25 a forefoot amputation would be sufficient and for a score of>25 a toe amputation would be all that was required. The use of a scoring system dependent on the preoperative angiogram to assess the run-off vessel situation provides a practicable and direct way to help predict the level of amputation in an ischaemic lower extremity. However, it is not totally reliable and should be used as one of the factors to be considered when an amputation is required. [ABSTRACT FROM AUTHOR]