950 resultados para Segments of signs
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I investigated effects of annual spring flows on the abundance of Rio Grande silvery minnow, red shiner, and fathead minnow within two segments of the Middle Rio Grande (i.e., above and below the Rio Puerco) using 12 years of data. Rio Grande silvery minnow abundance was positively related to high spring flows and negatively related to low spring flows. Conversely, the abundance of the red shiner and fathead minnow were negatively related to high spring flows and positively related to low spring flows. The strength of these relationships varied with species and location but results from analyses below the Rio Puerco showed a stronger positive and negative relationship (with high and low spring flows, respectively) for Rio Grande silvery minnow.
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Lidocaine bears in its structure both an aromatic ring and a terminal amine, which can be protonated at physiological pH, linked by an amide group. Since lidocaine causes multiple inhibitory actions on nicotinic acetylcholine receptors (nAChRs), this work was aimed to determine the inhibitory effects of diethylamine (DEA), a small molecule resembling the hydrophilic moiety of lidocaine, on Torpedo marmorata nAChRs microtransplanted to Xenopus oocytes. Similarly to lidocaine, DEA reversibly blocked acetylcholine-elicited currents (IACh) in a dose-dependent manner (IC50 close to 70 μM), but unlike lidocaine, DEA did not affect IACh desensitization. IACh inhibition by DEA was more pronounced at negative potentials, suggesting an open-channel blockade of nAChRs, although roughly 30% inhibition persisted at positive potentials, indicating additional binding sites outside the pore. DEA block of nAChRs in the resting state (closed channel) was confirmed by the enhanced IACh inhibition when pre-applying DEA before its co-application with ACh, as compared with solely DEA and ACh co-application. Virtual docking assays provide a plausible explanation to the experimental observations in terms of the involvement of different sets of drug binding sites. So, at the nAChR transmembrane (TM) domain, DEA and lidocaine shared binding sites within the channel pore, giving support to their open-channel blockade; besides, lidocaine, but not DEA, interacted with residues at cavities among the M1, M2, M3, and M4 segments of each subunit and also at intersubunit crevices. At the extracellular (EC) domain, DEA and lidocaine binding sites were broadly distributed, which aids to explain the closed channel blockade observed. Interestingly, some DEA clusters were located at the α-γ interphase of the EC domain, in a cavity near the orthosteric binding site pocket; by contrast, lidocaine contacted with all α-subunit loops conforming the ACh binding site, both in α-γ and α-δ and interphases, likely because of its larger size. Together, these results indicate that DEA mimics some, but not all, inhibitory actions of lidocaine on nAChRs and that even this small polar molecule acts by different mechanisms on this receptor. The presented results contribute to a better understanding of the structural determinants of nAChR modulation.
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The Bushranger Copper project is a known porphyry-style copper deposit located roughly 150 km west of Sydney in New South Wales, Australia. Monterey pines (Pinus radiata) growing over the mineralization were cored and their rings were counted. Segments of the core representing growth between 2003 and 2008 were selected, digested in nitric acid, and analyzed via ICP-MS. This time span was selected because there was the least variation in tree ring width among all samples during these years, indicating uniform growth. The relative concentrations of the pathfinder elements Al, Cu, Mo, Pb and Zn were highest in the south-western corner of the area. Based on the data this area is the most prospective area to conduct further exploration efforts.
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Highlights • Low interest rates, asset purchases and other accommodative monetary policy measures tend to increase asset prices and thereby benefit the wealthier segments of society, at least in the short-term, given that asset holdings are mainly concentrated among richest households. • Such policies also support employment, economic activity, incomes and inflation, which can benefit the poor and middle-class, which have incomes more dependent on employment and which tend to spend a large share of their income on debt service. • Monetary policy should focus on its mandate, while fiscal and social policies should address widening inequalities by revising the national social redistribution systems for improved efficiency, intergenerational equity and fair burden sharing between the wealthy and poor.
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We study the vulnerability of 130 banks directly supervised by the European Central Bank’s Single Supervisory Mechanism. Illustrative stress tests using banks’ balance sheet data reveal that significant stress prevails in the euro area’s smaller and medium-sized banks, many of them located in southern Europe. The banks we identify as stressed also have performed substantially worse on the stock market. The vulnerable banks are typically hobbled by non-performing loans to European businesses. Strengthening the banking system, therefore, is important to achieve sustainable recovery because it will revitalise credit to the healthier segments of the economy. But instead of emphasising bank recapitalisation, as in past years, we believe the task is to shrink the banking sector to a healthier core.
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This paper discusses the application of the new European rules for burden-sharing and bail-in in the banking sector, in view of their ability to accommodate broader policy goals of aggregate financial stability. It finds that the Treaty principles and the new discipline of state aid and the restructuring of banks provide a solid framework for combating moral hazard and removing incentives that encourage excessive risk-taking by bankers. However, the application of the new rules may have become excessively attentive to the case-by-case evaluation of individual institutions, while perhaps losing sight of the aggregate policy needs of the banking system. Indeed, in this first phase of the banking union, while large segments of the EU banking sector still require a substantial restructuring and recapitalisation, the market may not be able to provide all the needed resources in the current environment of depressed profitability and low growth. Thus, a systemic market failure may be making the problem impossible to fix without resorting to temporary public support. But the risk of large write-offs of capital instruments due to burden-sharing and bail-in may represent an insurmountable obstacle to such public support as it may set in motion an investors’ flight. The paper concludes by showing that existing rules do contain the flexibility required to accommodate aggregate policy requirements in the general interest, and outlines a public support scheme for the precautionary recapitalisation of solvent banks that would be compliant with EU law.
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Master thesis discusses the analysis of changes in biological signals on time based on dynamic time warping algorithm (DTW). Special attention is paid to problems of tiny changes analysis incomplex nonstationary biological signals. Electrocardiographic (ECG) signals are used as an example inthis study; in particular, repolarization segments of heart beat cycles. The aim of the research is studyingthe possibility of applying DTW algorithm for the analysis of small changes in the repolarization segments of heart beat cycles. The research has the following tasks:- Studying repolarization segments of heart beat cycles, andmethods of their analysis;- Studying DTW algorithm and its modifications, finding the most appropriate modification for analyzing changes in biological signals;- Development of methods for analyzing the warping path(output parameter of DTW algorithm).
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Panktonic foraminiferal tests of the spinose species Orbulina universa, of the non-spinose Globorotalia tumida-menardii complex, and of a mixed species assemblage (grain size fraction 200-400 µm) were isolated from Sierra Leone Rise core GIK13519-2 and analyzed for free, total, and bound (by difference) amino acids to study the isoleucine epimerization mechanism in fossil foraminiferal tests and to define empirical calibration curves for dating deep-sea sediments over the past 900,000 years. Total isoleucine epimerization curves typically separate into three "linear" segments of decreasing apparents rates with increasing time and exhibit a pronounced "species effect". The degree of epimerization attained at time is considerably lower in O. universa than in G. tumida-menardii while the mixed species results scatter between the limits delineated by the two monospecific curves. Total allo/iso ratios are closely related to the proportion of free to total isoleucine accumulating in the tests indicating that the rate of hydrolysis of matrix proteins and peptides controls the overall epimerization reaction. The results are consistent with experimental evidenve where upon isoleucine epimerizes at a rapid rate in terminal positions but at slow rates in interior positions as well as in the free state. Notwithstanding free isoleucine exhibits the highest degree of epimerized terminal isoleucine. Species-specific hydrolysis and epimerization rates are maintained until about 50 % of bound isoleucine have been hydrolyzed to the free state corresponding to a total allo/iso ratio of about 0.5. Remaining peptide units appear to be more resistent against hydrolysis and separate species then show the same apparent epimerization rate dominantly controlled by the slow conversion rate in the free state until equilibrium is achieved in Miocene samples under deep-ocean temperature conditions. The degree of epimerization attained at comparable time in separate species will, however, remain different due to different initial rates of hydrolysis.
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Time series analyses of atmospheric and oceanic variables in a late Pleistocene record from the northwest Pacific show the complex relationship of the response of various segments of the climate system to changes in the earth's orbit. Most variance spectra of time series from this subarctic record contain frequency peaks with periods corresponding to at least one of the major orbital components of eccentricity, obliquity, or precession. Although the radiolarian faunal (water mass) assemblages have prominent spectral peaks with 41,000-year periods which are coherent with obliquity at this frequency, only the Transitional faunal assemblage contains variance focused at a frequency corresponding to the 100,000-year period of eccentricity. Three of these faunal time series also show variance concentrated at a frequency with a 20,000-year period. These three time series are not coherent at a 20,000-year frequency with either of the dominant spectral peaks of precession. They are coherent, however, with variations in the second harmonic of the obliquity cycle. Changes in obliquity apparently affect siliceous faunal abundances in the northwest Pacific region of this high-latitude site more than variations in eccentricity or precession. Maxima in the time series of quartz abundance occur during low values of eccentricity and high glacial ice volume. Because atmospheric winds serve as the major source of supply of quartz to the sediments at this site, these high quartz values reflect increased aridity at the source region. Except for short periods during interglacials, the characteristics of the surface waters in this region of the subarctic Pacific during much of the last 460,000 years were similar to those which exist today in the Sea of Okhotsk. The spectrum of winter sea surface temperature estimates, derived from siliceous microfaunal abundances, contains dominant frequency peaks at periods of 100,000, 41,000, and 23,000 years which are coherent with eccentricity, obliquity, and precession, respectively. Based upon the relationship of the Subarctic Front with the dominance of specific faunal asemblages, the front was positioned south of its present-day location throughout much of the late Pleistocene.
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The structural and dynamic properties of dioctadecyldimethylammoniums (DODDMA) intercalated into 2:1 layered clays are investigated using isothermal-isobaric (NPT) molecular dynamics (MD) simulation. The simulated results are in reasonably good agreement with the available experimental measurements, such as X-ray diffraction (XRD), atom force microscopy (AFM), Fourier transform infrared (FTIR), and nuclear magnetic resonance (NMR) spectroscopies. The nitrogen atoms are found to be located mainly within two layers close to the clay surface whereas methylene groups form a pseudoquadrilayer structure. The results of tilt angle and order parameter show that interior two-bond segments of alkyl chains prefer an arrangement parallel to the clay surface, whereas the segments toward end groups adopt a random orientation. In addition, the alkyl chains within the layer structure lie almost parallel to the clay surface whereas those out of the layer structure are essentially perpendicular to the surface. The trans conformations are predominant in all cases although extensive gauche conformations are observed, which is in agreement with previous simulations on n-butane. Moreover, an odd-even effect in conformation distributions is observed mainly along the chains close to the head and tail groups. The diffusion constants of both nitrogen atoms and methylene groups in these nanoconfined alkyl chains increase with the temperature and methelene position toward the tail groups.
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1 The effects of calcium channel blockers on co-transmission from different populations of autonomic vasomotor neurons were studied on isolated segments of uterine artery and vena cava from guinea-pigs. 2 Sympathetic, noradrenergic contractions of the uterine artery (produced by 200 pulses at 1 or 10 Hz; 600 pulses at 20 Hz) were abolished by the N-type calcium channel blocker omega-conotoxin (CTX) GVIA at 1-10 nM. 3 Biphasic sympathetic contractions of the vena cava (600 pulses at 20 Hz) mediated by noradrenaline and neuropeptide Y were abolished by 10 nM CTX GVIA. 4 Neurogenic relaxations of the uterine artery (200 pulses at 10 Hz) mediated by neuronal nitric oxide and neuropeptides were reduced < 50% by CTX GVIA 10-100 nM. 5 Capsaicin (3 muM) did not affect the CTX GVIA-sensitive or CTX GVIA-resistant neurogenic relaxations of the uterine artery. 6 The novel N-type blocker CTX CVID (100-300 nM), P/Q-type blockers agatoxin IVA (10-100 nM) or CTX CVIB (100 nM), the L-type blocker nifedipine (10 muM) or the 'R-type' blocker SNX-482 (100 nM), all failed to reduce CTX GVIA-resistant relaxations. The T-type channel blocker NiCl2 (100-300 muM) reduced but did not abolish the remaining neurogenic dilations. 7 Release of different neurotransmitters from the same autonomic vasomotor axon depends on similar subtypes of calcium channels. N-type channels are responsible for transmitter release from vasoconstrictor neurons innervating a muscular artery and capacitance vein, but only partly mediate release of nitric oxide and neuropeptides from pelvic vasodilator neurons.
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Small molecules designed to mimic specific structural components of a protein (peptide strands, sheets, turns, helices, or amino acids) can be expected to display agonist or antagonist biological responses by virtue of interacting with the same receptors that recognize the protein. Here we describe some minimalist approaches to structural mimetics of amino acids and of strand, turn, or helix segments of proteins. The designed molecules show potent and selective inhibition of protease, transferase, and phospholipase enzymes, or antagonism of G-protein coupled or transcriptional receptors, and have potent anti-tumour, anti-inflammatory, or antiviral activity.
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Aims The major aims of the study were to compare the safety of a continuous low-dose estradiol-releasing vaginal ring (ESTring) to that of a vaginal estradiol tablet (Vagifem®) on the endometrium and the relief of subjective symptoms and signs of urogenital estrogen deficiency. Quality of life and acceptability of treatment delivery were also assessed. Study design A prospective, randomized study in which women were assigned in a 2: 1 ratio to ESTring and Vagifem and followed for 12 months. The primary endpoint was endometrial safety, based on the results of ultrasound measurement of endometrial thickness and a progestogen challenge test at baseline and week 48. Efficacy was determined by subjective assessment of urogenital estrogen deficiency symptoms at baseline and weeks 3, 12, 24, 36 and 48 and assessment of signs of vaginal epithelial atrophy by the clinician at baseline, 12 and 48 weeks. In addition, pelvic floor strength, vaginal cytological evaluation and pH, bacteruria and patient acceptability were assessed. Quality of life was assessed using a menopause-specific quality-of-life questionnire and a 2-day bladder diary at baseline and 12 and 48 weeks. The comparability of the two groups was assessed using ANOVA, χ(2) or Fisher's exact tests. Results A total of 126 women were randomized to ESTring and 59 to Vagifem. There was no statistical difference between the groups in the alleviation of symptoms and signs of urogenital estrogen deficiency. Maturation indices increased in both groups, from generally atrophic at baseline to proliferative or highly proliferative at 48 weeks. After 48 weeks of treatment, there was no statistically significant difference in endometrial thickness between the two groups. A statistically smaller proportion of bleeding/spotting occurred in the ESTring group (n = 0) compared to the Vagifem users (n = 4). Estradiol and total estrone serum levels increased during treatment in both groups but remained within the normal postmenopausal range. General health status in both groups was unchanged but the urogenital component of health burden was significantly improved in both groups. Bladder diary variables showed no differences between treatment groups. Conclusion Equivalent endometrial safety and efficacy in the relief of the symptoms and signs of urogenital estrogen deficiency were demonstrated for the 12 months' use of a low-dose estradiol-releasing vaginal ring and a vaginal estradiol tablet.
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Background: Published birthweight references in Australia do not fully take into account constitutional factors that influence birthweight and therefore may not provide an accurate reference to identify the infant with abnormal growth. Furthermore, studies in other regions that have derived adjusted (customised) birthweight references have applied untested assumptions in the statistical modelling. Aims: To validate the customised birthweight model and to produce a reference set of coefficients for estimating a customised birthweight that may be useful for maternity care in Australia and for future research. Methods: De-identified data were extracted from the clinical database for all births at the Mater Mother's Hospital, Brisbane, Australia, between January 1997 and June 2005. Births with missing data for the variables under study were excluded. In addition the following were excluded: multiple pregnancies, births less than 37 completed week's gestation, stillbirths, and major congenital abnormalities. Multivariate analysis was undertaken. A double cross-validation procedure was used to validate the model. Results: The study of 42 206 births demonstrated that, for statistical purposes, birthweight is normally distributed. Coefficients for the derivation of customised birthweight in an Australian population were developed and the statistical model is demonstrably robust. Conclusions: This study provides empirical data as to the robustness of the model to determine customised birthweight. Further research is required to define where normal physiology ends and pathology begins, and which segments of the population should be included in the construction of a customised birthweight standard.
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The foraging process of location and exploitation of food in complex termite societies is in part reliant upon unequal division of specific tasks amongst its members (polyethism). To conduct studies assessing the role of individuals in foraging activities it is necessary to have descriptors of worker caste and instar. Here we provide biometric descriptors of specific caste and instar for worker caste and instars of Microcerotermes turneri (Froggatt) (Termitidae: Termitinae) for the worker castes (male and female) for the identification of individuals in laboratory assays applicable across multiple nests. The use of head width for determining sex of workers was successful across multiple nests. The length of the first three flagellum segments of the antenna and tibia three could be used to determine worker instar.