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We present results from a multiwavelength study of the blazar PKS 1954–388 at radio, UV, X-ray, and gamma-ray energies. A RadioAstron observation at 1.66 GHz in June 2012 resulted in the detection of interferometric fringes on baselines of 6.2 Earth-diameters. This suggests a source frame brightness temperature of greater than 2 × 1012 K, well in excess of both equipartition and inverse Compton limits and implying the existence of Doppler boosting in the core. An 8.4-GHz TANAMI VLBI image, made less than a month after the RadioAstron observations, is consistent with a previously reported superluminal motion for a jet component. Flux density monitoring with the Australia Telescope Compact Array confirms previous evidence for long-term variability that increases with observing frequency. A search for more rapid variability revealed no evidence for significant day-scale flux density variation. The ATCA light-curve reveals a strong radio flare beginning in late 2013, which peaks higher, and earlier, at higher frequencies. Comparison with the Fermi gamma-ray light-curve indicates this followed ~ 9 months after the start of a prolonged gamma-ray high-state—a radio lag comparable to that seen in other blazars. The multiwavelength data are combined to derive a Spectral Energy Distribution, which is fitted by a one-zone synchrotron-self-Compton (SSC) model with the addition of external Compton (EC) emission.
We read with great interest the opinions of Apostolopoulou & Adams (2015) on biodiversity offsetting. We agree with the authors that offsetting has more profound implications than a technical approach to the subject would suggest. Our experience with developments on the mitigation of impacts on biodiversity in government policy, financial lenders’ safeguards and corporate practice is that the political, economic, social and financial implications weigh just as heavily in decision-makers’ minds as the technical ones that Apostolopoulou & Adams raise (IFC, 2012; BBOP, 2012b; ten Kate & Crowe, 2014; IUCN, 2016; Maron et al., 2016b). The governments, companies and communities working with scientists on the mitigation hierarchy regard biodiversity offsets as one of many tools available not only for conservation but also for risk management, social and economic engagement and benefit-sharing, land-use and landscape-level planning, and sustainable development (IFC, 2012; CSBI, 2015).
Accelerator mass spectrometry (AMS) radiocarbon dating and paleoecological analysis of slope deposits at Mt Raizan provided seven 14C dates indicating that landslides occurred in that area at 6.0 to 6.3 cal ka BP and 6.5 cal ka BP. Plant macrofossils, pollen grains, and spores point to a mixed forest at that time, consisting of conifers and broad-leaved trees. On the other hand, insect fossil indicates slightly colder climate than that of the flora. This difference may be attributed to varied sensitivities of each proxy to climatic changes.
The widespread prevalence of diabetes, caused by impaired insulin secretion and insulin resistance, is now a worldwide health problem. Glucagon-like peptide 1 (GLP-1) is a major intestinal hormone that stimulates glucose-induced insulin secretion from β cells. Prolonged activation of the GLP-1 signal has been shown to attenuate diabetes in animals and human subjects. Therefore, GLP-1 secretagogues are attractive targets for the treatment of diabetes. Recent epidemiological studies have reported that an increase in daily coffee consumption lowers diabetes risk. The present study examined the hypothesis that the reduction in diabetes risk associated with coffee consumption may be mediated by the stimulation of GLP-1 release by coffee polyphenol extract (CPE). GLP-1 secretion by human enteroendocrine NCI-H716 cells was augmented in a dose-dependent manner by the addition of CPE, and was compatible with the increase in observed active GLP-1(7–36) amide levels in the portal blood after administration with CPE alone in mice. CPE increased intracellular cyclic AMP (cAMP) levels in a dose-dependent manner, but this was not mediated by G protein-coupled receptor 119 (GPR119). The oral administration of CPE increased diet (starch and glyceryl trioleate)-induced active GLP-1 secretion and decreased glucose-dependent insulinotropic polypeptide release. Although CPE administration did not affect diet-induced insulin secretion, it decreased postprandial hyperglycaemia, which indicates that higher GLP-1 levels after the ingestion of CPE may improve insulin sensitivity. We conclude that dietary coffee polyphenols augment gut-derived active GLP-1 secretion via the cAMP-dependent pathway, which may contribute to the reduced risk of type 2 diabetes associated with daily coffee consumption.
This paper analyzes the effect of labeling information on U.S. farmers' herbicide choices. Herbicide choices reported by U.S. soybean farmers are used to estimate farmer preferences for different herbicide attributes using a mixed logit model. Our results indicate that statements displayed on pesticide labels regarding risks to human health and the environment are important components in herbicide selection. We find that farmers are willing to pay an average of $27 per acre to avoid using an herbicide labeled with the word “Warning” and $38 per acre to avoid using an herbicide labeled with the word “Danger.”
Postprandial energy metabolism, including postprandial hyperglycaemia, hyperinsulinaemia and hyperlipidaemia, is related to the risk for developing obesity and CVD. In the present study, we examined the effects of polyphenols purified from coffee (coffee polyphenols (CPP)) on postprandial carbohydrate and lipid metabolism, and whole-body substrate oxidation in C57BL/6J mice. In mice that co-ingested CPP with a lipid–carbohydrate (sucrose or starch)-mixed emulsion, the respiratory quotient determined by indirect calorimetry was significantly lower than that in control mice, whereas there was no difference in VO2 (energy expenditure), indicating that CPP modulates postprandial energy partitioning. CPP also suppressed postprandial increases in plasma glucose, insulin, glucose-dependent insulinotropic polypeptide and TAG levels. Inhibition experiments on digestive enzymes revealed that CPP inhibits maltase and sucrase, and, to a lesser extent, pancreatic lipase in a concentration-dependent manner. Among the nine kinds of polyphenols (caffeoyl quinic acids (CQA), di-CQA, feruloyl quinic acids (FQA)) contained in CPP, di-CQA showed more potent inhibitory activity than CQA or FQA on these digestive enzymes, suggesting a predominant role of di-CQA in the regulation of postprandial energy metabolism. These results suggest that CPP modulates whole-body substrate oxidation by suppressing postprandial hyperglycaemia and hyperinsulinaemia, and these effects are mediated by inhibiting digestive enzymes.
We discuss the application of x-ray scattering and fluorescence to the problem of unravelling the relationship between the structural and magnetic properties of magnetic multilayers. Particular attention is paid to the use of grazing incidence diffuse scatter to determine the compositional gradient, out-of-plane roughness amplitude, in-plane correlation length and fractal parameter of buried interfaces. Anomalous scattering provides information on the local environment of specific atoms and grazing incidence fluorescence is a depth -sensitive probe of chemical composition. We present examples indicating the sensitivity limits and the reproducibility of the techniques, all from multiple layer structures of magnetic metals.
SrTiO3 and (Ba,Sr)TiO3 thin films have been prepared by ion beam sputtering on Pd coated sapphire substrates. Film compositions were almost the same as target compositions when powder targets were used. Capacitance-voltage characteristics depended on Sr/Ti ratio of the SrTiO3 films. Only small changes of capacitance value were observed in the range from -3V to 3V when the Sr/Ti ratio was 1.0. Compared with rf-magnetron sputtered film, ion beam sputtered SrTiO3 film indicated lower leakage current density in 50nm thickness. In (Bax,Sr1-x)TiO3 thin films, dielectric constant changed with Ba content (x) and showed a maximum at x=0.5. It also changed with the firing temperature of target powder. The highest value was obtained by using the target powder fired at 900°C. A 100nm thick (Ba0.5,Sr0.5)TiO3 thin film indicated a dielectric constant value of 320.
We report the epitaxial growth of CuO thin films prepared by lowenergy and high-density O+ ion beams mass-separated from an oxygen plasma. We have successfully produced O+ beams of 50 μA/cm2 while maintaining an ambient pressure of 3×10−9 Torr during the growth. CuO grows on MgO(100) with epitaxial relationship of (111)CuO // (100)MgO and CuO // MgO at room temperature and even under conditions where the flux density of O+ beams is at least one order of magnitude lower than the minimum flux density of O2 required to form CuO.
The aim of the present study was to investigate the effects of hydroxypropyl-distarch phosphate (HDP) supplementation on postprandial energy metabolism and glucose-dependent insulinotropic polypeptide (GIP) in human subjects. A total of ten healthy male subjects, with a mean BMI of 23·6 (sem 1·3) kg/m2, age 35·2 (sem 1·9) years and body weight 71·1 (sem 4·0) kg, participated in a randomised, cross-over, intervention study with two different test meals (1673·6 kJ) containing either waxy maize starch or HDP from waxy maize starch (degree of substitution 0·154, P content 0·004 %). Resting energy expenditure (REE) and blood concentrations of various biomarkers were measured at fasting and up to 180 min postprandially. Indirect calorimetry showed that the HDP meal caused higher REE (P < 0·05) and fat utilisation (P < 0·001) than the waxy maize starch meal. The HDP meal led to significantly lower postprandial glucose (P < 0·05), insulin (P < 0·05) and GIP (P < 0·05) responses than the waxy maize starch meal. Both postprandial REE (R − 0·576, P < 0·01) and fat utilisation (R − 0·514, P < 0·05) were negatively correlated with the postprandial GIP response, but not with the glucose and insulin responses. In conclusion, dietary supplementation with HDP lowers postprandial GIP and increases postprandial REE and fat utilisation in healthy humans. An HDP-rich diet may therefore have beneficial implications in weight management. Further studies are required to confirm the efficacy in overweight or obese subjects, and to determine the precise mechanisms.
Superconducting films of YBa2Cu3O7-δ have been fabricated by pulsed laser deposition technique applying bias voltage to a substrate up to +/-500 V. It has been found that substrate bias voltages are effective for preparing the fidms with high Tc and high crystalline quality at lower substrate temperatures. Positive bias is more effective than negative one. Time resolved observation has been carried out in order to investigate the influence of biasing on the plume and revealed three kinds of light emission. The first is an ordinary plume with a velocity of 6×105 cm/s, which is independent of biasing. It suggests that most of the luminous particles in the plume are electrically neutral. The second is oxygen plasma with a short life time, which is triggered by laser pulse under the positive bias and triggered by arrival of the plume in 8 ps after the laser pulse under the negative bias. The third is an additional plume with a velocity of 3×105 cm/s. The oxygen plasma and additional plume have improved superconducting properties of films deposited with biasing to the substrate.
Structural and electrical properties were investigated for chemically prepared SrBi2Ta2O9(SBT) thin films on Pt/Ti/SiO2/Si substrates. Good ferroelectric properties were obtained with a Pt top electrode: Pr=10.0μC/cm2 and Ec-34kV/cm. Au top electrodes resulted in smaller Pr. However, no fatigue was observed up to 109 switching cycles regardless of the top electrode material. Grains were spherical, not columnar, and the average grain size was 200nm. A marked structural change took place in the bottom Pt/Ti electrode during film preparation. The SIMS analysis indicates the reaction between Bi and Pt
Effects of off-stoichiometry and Nb substitution on the dielectric anomaly and ferroelectric properties have been investigated for SrBi2Ta2O9(SBT) thin films. Local atomic environment for the stoichiometric and off-stoichiometric SBT films has been also measured. The features of the dielectric anomaly, the Curie temperature (Tc), and the temperature dependence of the spontaneous polarization (Ps) are independent of the film thickness, and are governed by the nature of the crystal. For the stoichiometric Sr content SBT films, the grain size increases and the temperature dependence of the remanent polarization (Pr) decreases with increasing thickness. For the films with Sr/Bi/Ta = 0.8/2/2 and 0.8/2.2/2, Sr deficient local structure was observed, and such lattice structure probably leads to higher Tc than the stoichiometric crystal. Nb substitution for Ta also raises Tc, and makes the dielectric anomaly sharper. The phase transition associated with the dielectric anomaly for these films is thought to be first-order.
Thin films of CuAlO2, CuGaO2 and AglnO2 with delafossite structure were prepared on sapphire substrates by pulsed laser deposition method. The resulting CuA102 thin films exhibited p-type conduction and the electrical conductivity at room temperature was 0.3 Scm−1. CuGaO2 thin films were grown epitaxially on μ-Al2O3 (001) surface and showed p-type conduction (conductivity at room temperature = 0.06 S cm−1). The optical band gap was estimated to be ∼3.5 eV for CuAlO2 or ∼3.6 eV for CuGaO2. On the other hand, the thin film of Sn doped AglnO2 exhibited n-type conduction. The optical band gap and electrical conductivity at room temperature were ∼4.1 eV and 70 S cm−1, respectively. The recent work demonstrates the validity of our chemical design concept for p- and n-type transparent conducting oxides, providing an opportunity for realization of transparent p-n junction using delafossite-type oxides.
A total of 299 fish belonging to ten teleost species were studied in Iranian waters at the north-eastern coast of the Persian Gulf for larval trypanorhynch cestode infection. The following trypanorhynch species were identified: Callitetrarhynchus gracilis Pintner, 1931, Pseudogilquinia thomasi (Palm, 2000), Pterobothrium lesteri Campbell and Beveridge, 1996 and Pseudolacistorhynchus shipleyi (Southwell, 1929). The most abundant parasite was C. gracilis which was isolated from seven teleost species. The highest prevalence (62.9%) and dominance (0.98) were demonstrated for P. thomasi with a maximum intensity of 22 in Indian halibut Psettodes erumei. Collections of P. lesteri and P. shipleyi from the Persian Gulf represent new locality records, thus extending the known range of distribution for both species. Four new host records are established. The recorded combination of trypanorhynch species and the established host range correspond to other regions, such as off the Brazilian coast. In terms of species distribution, the north-western part of the Indian Ocean, together with the Gulf of Bengal and the Indonesian archipelago, share the same species, resulting from connected water bodies. All trypanorhynch species were isolated from the body cavity, except for P. thomasi which was recorded from the musculature of P. erumei. Relatively high intensities of infection in P. erumei may be of public health concern in the region, necessitating the consumption of well-cooked fish products.
Interior-Point Methods (IPMs) are not only very effective in practice for solving linear optimization problems but also have polynomial-time complexity. Despite the practical efficiency of large-update algorithms, from a theoretical point of view, these algorithms have a weaker iteration bound with respect to small-update algorithms. In fact, there is a significant gap between theory and practice for large-update algorithms. By introducing self-regular barrier functions, Peng, Roos and Terlaky improved this gap up to a factor of log n. However, checking these self-regular functions is not simple and proofs of theorems involving these functions are very complicated. Roos el al. by presenting a new class of barrier functions which are not necessarily self-regular, achieved very good results through some much simpler theorems. In this paper we introduce a new kernel function in this class which yields the best known complexity bound, both for large-update and small-update methods.
In this study the lead and cadmium concentrations in the liver, intestine, muscle and gonad of the shark Carcharhinus dussumieri and its parasites, Anthobothrium sp. and Paraorigmatobothrium sp. (Cestoda), were measured and compared. Tissue samples were collected from Iranian coastal waters of the Persian Gulf. After tissue preparation, the cadmium and lead concentrations were analysed using the Inductively Coupled Plasma technique. The results revealed that lead and cadmium concentrations in both parasite species were many times higher than in the host tissues. The results strongly support the view that helminth parasites are extremely sensitive early warning bioindicators, particularly in sensitive environments under threat but where pollution levels are presently low. They may also have a beneficial effect on the health of their hosts by acting as heavy metal filters.
The acrosome reaction (AR) is a fundamental event for fertilization, which is induced in concert with acrosome reaction-inducing substance (ARIS) and asterosap, both of which are components of starfish egg jelly (EJ). During the AR, a spermatozoon undergoes a series of physiological changes, such as in intracellular cGMP concentration ([cGMP]i), pHi and intracellular Ca2+ concentration ([Ca2+]i). Affinity purification of cGMP-binding protein resulted in the isolation of a regulatory subunit of the cAMP-dependent protein kinase A (PKA), suggesting the involvement of a cAMP-dependent pathway in the AR. By using a cAMP enzyme immunoassay, [cAMP]i was found to increase in starfish spermatozoa when stimulated with ARIS and asterosap. ARIS could also increase the [cAMP]i in the presence of high pH seawater. Pretreatment of spermatozoa with two specific and cell-permeable PKA inhibitors, H89 and KT5720, prevented the induction of the AR in a concentration-dependent manner. These results suggest that PKA activity participates in the induction of the AR with ARIS and asterosap. To investigate this, we have cloned a gene that encodes a regulatory subunit of PKA that had been identified in starfish spermatozoa.