452 resultados para 1238


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This technical report builds on previous reports to derive the likelihood and its derivatives for a Gaussian Process with a modified Bessel function based covariance function. The full derivation is shown. The likelihood (with gradient information) can be used in maximum likelihood procedures (i.e. gradient based optimisation) and in Hybrid Monte Carlo sampling (i.e. within a Bayesian framework).

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Copper(II) complexes of hexadentate ethylenediaminetetracarboxylic acid type ligands Heda3p and Heddadp (Heda3p = ethylenediamine-N-acetic-N,N',N'-tri-3-propionic acid; H eddadp = ethylenediamine-N,N'-diacetic-N,N'-di-3- propionic acid) have been prepared. An octahedral trans(O) geometry (two propionate ligands coordinated in axial positions) has been established crystallographically for the Ba[Cu(eda3p)]·8HO compound, while Ba[Cu(eddadp)]·8HO is proposed to adopt a trans(O ) geometry (two axial acetates) on the basis of density functional theory calculations and comparisons of IR and UV-vis spectral data. Experimental and computed structural data correlating similar copper(II) chelate complexes have been used to better understand the isomerism and departure from regular octahedral geometry within the series. The in-plane O-Cu-N chelate angles show the smallest deviation from the ideal octahedral value of 90°, and hence the lowest strain, for the eddadp complex with two equatorial ß-propionate rings. A linear dependence between tetragonality and the number of five-membered rings has been established. A natural bonding orbital analysis of the series of complexes is also presented.

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A relation showing that the Grünwald-Letnikov and generalized Cauchy derivatives are equal is deduced confirming the validity of a well known conjecture. Integral representations for both direct and reverse fractional differences are presented. From these the fractional derivative is readily obtained generalizing the Cauchy integral formula.

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Simple features such as edges are the building blocks of spatial vision, and so I ask: how arevisual features and their properties (location, blur and contrast) derived from the responses ofspatial filters in early vision; how are these elementary visual signals combined across the twoeyes; and when are they not combined? Our psychophysical evidence from blur-matchingexperiments strongly supports a model in which edges are found at the spatial peaks ofresponse of odd-symmetric receptive fields (gradient operators), and their blur B is givenby the spatial scale of the most active operator. This model can explain some surprisingaspects of blur perception: edges look sharper when they are low contrast, and when theirlength is made shorter. Our experiments on binocular fusion of blurred edges show that singlevision is maintained for disparities up to about 2.5*B, followed by diplopia or suppression ofone edge at larger disparities. Edges of opposite polarity never fuse. Fusion may be served bybinocular combination of monocular gradient operators, but that combination - involvingbinocular summation and interocular suppression - is not completely understood.In particular, linear summation (supported by psychophysical and physiological evidence)predicts that fused edges should look more blurred with increasing disparity (up to 2.5*B),but results surprisingly show that edge blur appears constant across all disparities, whetherfused or diplopic. Finally, when edges of very different blur are shown to the left and righteyes fusion may not occur, but perceived blur is not simply given by the sharper edge, nor bythe higher contrast. Instead, it is the ratio of contrast to blur that matters: the edge with theAbstracts 1237steeper gradient dominates perception. The early stages of binocular spatial vision speak thelanguage of luminance gradients.

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Kornai János eddigi életművében központi szerepet játszott a szocialista és kapitalista rendszer működési sajátosságainak megértése, leírása egy olyan elméleti keretben, amely összekapcsolja az elemzés analitikus és empirikus, elméleti és történeti vonatkozásait. Ez a munka egyszerre tette szükségessé az apró részletek gondos összegyűjtését és az elemekből kirakható nagy egész átlátását. Ehhez – a szükséges képességeken túl – önfegyelemre, a tárggyal szembeni alázatra, odaadásra és sok-sok munkára lehetett szükség. Vajon mi ösztökélte e fáradtságos munkára a szerzőt? A kíváncsiság? Az új összefüggések felfedezésének intellektuális izgalma? A rejtvények megoldásának öröme? Nos, mindezek mellett még valami más is: a gyakorlati változtatás igénye. Kornai János a tudományt a gyakorlat megváltoztatásának eszközeként is műveli. Számára a szigorú tudományos elemzés a gyakorlati cselekvési alternatívák közötti választást is segíti. Kornai János számára a tudomány fontos emberi, ha tetszik politikai értékeket szolgál. Munkáinak belső elméletilogikai koherenciája a gondolkodó és cselekvő ember koherenciáját szolgálja. Kornai János 85. születésnapja tiszteletére a Budapesti Corvinus Egyetem, a Közép-európai Egyetem és a Magyar Nemzeti Bank nemzetközi konferenciát rendezett.

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Charles Edward Perry (Chuck), 1937-1999, was the founding president of Florida International University in Miami, Florida. He grew up in Logan County, West Virginia and received his bachelor's and masters's degrees from Bowling Green State University. He married Betty Laird in 1960. In 1969, at the age of 32, Perry was the youngest president of any university in the nation. The name of the university reflects Perry’s desire for a title that would not limit the scope of the institution and would support his vision of having close ties to Latin America. Perry and a founding corps opened FIU to 5,667 students in 1972 with only one large building housing six different schools. Perry left the office of President of FIU in 1976 when the student body had grown to 10,000 students and the university had six buildings, offered 134 different degrees and was fully accredited. Charles Perry died on August 30, 1999 at his home in Rockwall, Texas. He is buried on the FIU campus in front of the Graham Center entrance.

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This study investigates the impact of a combined treatment of Systematic Error Correction and Repeated Reading on reading rate and errors for 18 year olds with undiagnosed reading difficulties on a Caribbean Island. In addition to direct daily measures of reading accuracy, the Reading Self Perception Scale was administered to determine whether the intervention was associated with changes in the way the student perceives himself as a reader.

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A number of factors influence the information processing needs of organizations, particularly with respect to the coordination and control mechanisms within a hotel. The authors use a theoretical framework to illustrate alternative mechanisms that can be used to coordinate and control hotel operations.

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In a cross-sectional study design, risk factors for coronary heart disease (CHD) were evaluated in three groups: 66 Afro Caribbeans (FBCA) living in the US for less than 10 years, 62 US-born Afro Caribbean (USBCA) and 61 African American (AA) adults (18–40 years), with equal numbers of males and females in each group. Socio-demographic, dietary, anthropometric and blood pressure data were collected. Fasting blood glucose, blood lipids and high-sensitivity C-reactive protein (hs-CRP) were determined. ^ The USBCA and AA participants compared to the FBCA participants consumed significantly (p < 0.05) more mean total fat (g) (66.3 ± 41.7 and 73.0 ± 47.8 vs. 52.8 ± 32.3), saturated fat (g) (23.1 ± 14.9 and 24.9 ± 15.8 vs. 18.6 ± 11.5), percent energy from fat (%) (33.1 ± 6.5 and 31.4 ± 6.4 vs. 29.3 ± 6.8), fat servings (1.8 ± 1.2 and 1.5 ± 1.0 vs. 1.2 ± 0.9), dietary cholesterol (mg) (220.4 ± 161.9 and 244.1 ± 155.0 vs. 168.8 ± 114.0) and sodium (mg) (2245.2 ± 1238.3 and 2402.6 ± 1359.3 vs. 1838.0 ± 983.4) and less than 2 servings of fruits per day (%) (86.9 and 94.9 vs. 78.5). These differences were more pronounced in males compared to females and remained after correcting for age. Also, the percentages of USBCA and AA participants who were obese (17.1% and 23.0%, respectively) were significantly (p < 0.05) higher compared to FBCA (7.6%) participants. More USBCA and AA than FBCA individuals smoked cigarettes (4.8% and 6.6% vs. 0.0%) and consumed alcoholic beverages (29.0% and 50.8% vs. 24.2%). The mean hs-CRP level of the AA participants (2.2 ± 2.7 mg/L) was significantly (p < 0.01) higher compared to the FBCA (1.1 ± 1.3 mg/L) and USBCA (1.3 ± 1.6 mg/L) participants. ^ The FBCA participants had a better CHD risk profile than the USBCA and AA participants. Focus should be placed on the ethnic and cultural differences in a population to better understand the variations in health indicators among different ethnic groups of the same race. This focus can provide healthcare professionals and policy planners with the opportunity to develop culturally sensitive programs and strategies for the improvement of health outcomes. ^

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Vol. 21, Issue 16, 8 pages

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The role of source properties in across-formant integration was explored using three-formant (F1+F2+F3) analogues of natural sentences (targets). In experiment 1, F1+F3 were harmonic analogues (H1+H3) generated using a monotonous buzz source and second-order resonators; in experiment 2, F1+F3 were tonal analogues (T1+T3). F2 could take either form (H2 or T2). Target formants were always presented monaurally; the receiving ear was assigned randomly on each trial. In some conditions, only the target was present; in others, a competitor for F2 (F2C) was presented contralaterally. Buzz-excited or tonal competitors were created using the time-reversed frequency and amplitude contours of F2. Listeners must reject F2C to optimize keyword recognition. Whether or not a competitor was present, there was no effect of source mismatch between F1+F3 and F2. The impact of adding F2C was modest when it was tonal but large when it was harmonic, irrespective of whether F2C matched F1+F3. This pattern was maintained when harmonic and tonal counterparts were loudness-matched (experiment 3). Source type and competition, rather than acoustic similarity, governed the phonetic contribution of a formant. Contrary to earlier research using dichotic targets, requiring across-ear integration to optimize intelligibility, H2C was an equally effective informational masker for H2 as for T2.

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The need for elemental analysis of biological matrices such as bone, teeth, and plant matter for sourcing purposes has emerged within the forensic and geochemical laboratories. Trace elemental analyses for the comparison of aterials such as glass by inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS has been shown to offer a high degree of discrimination between different manufacturing sources. Unit resolution ICP-MS instruments may suffer from some polyatomic interferences including 40Ar16O+, 40Ar16O1H+, and 40Ca16O+ that affect iron measurement at trace levels. Iron is an important element in the analysis of glass and also of interest for the analysis of several biological matrices. A comparison of the nalytical performance of two different ICP-MS systems for iron analysis in glass for determining the method detection limits (MDLs), accuracy, and precision of the measurement is presented. Acid digestion and laser ablation methods are also compared. Iron polyatomic interferences were reduced or resolved by using dynamic reaction cell and high resolution ICP-MS. MDLs as low as 0.03 ìg g-1 and 0.14 ìg g-1 for laser ablation and solution based analyses respectively were achieved. The use of helium as a carrier gas demonstrated improvement in the detection limits of both iron isotopes (56Fe and 57Fe) in medium resolution for the HR-ICP-MS and with a dynamic reaction cell (DRC) coupled to a quadrupole ICP-MS system. The development and application of robust analytical methods for the quantification of trace elements in biological matrices has lead to a better understanding of the potential utility of these measurements in forensic chemical analyses. Standard reference materials (SRMs) were used in the development of an analytical method using HR-ICP-MS and LA-HR-ICP-MS that was subsequently applied on the analysis of real samples. Bone, teeth and ashed marijuana samples were analyzed with the developed method. Elemental analysis of bone samples from 12 different individuals provided discrimination between individuals, when femur and humerus bones were considered separately. Discrimination of 14 teeth samples based on elemental composition was achieved with the exception of one case where samples from the same individual were not associated with each other. The discrimination of 49 different ashed plant (cannabis)samples was achieved using the developed method.

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This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. This image is made available for non-commercial or educational use only.

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Continuous high-resolution mass accumulation rates (MAR) and X-ray fluorescence (XRF) measurements from marine sediment records in the Bay of Biscay (NE Atlantic) have allowed the determination of the timing and the amplitude of the 'Fleuve Manche' (Channel River) discharges during glacial stages MIS 10, MIS 8, MIS 6 and MIS 4-2. These results have yielded detailed insight into the Middle and Late Pleistocene glaciations in Europe and the drainage network of the western and central European rivers over the last 350 kyr. This study provides clear evidence that the 'Fleuve Manche' connected the southern North Sea basin with the Bay of Biscay during each glacial period and reveals that 'Fleuve Manche' activity during the glaciations MIS 10 and MIS 8 was significantly less than during MIS 6 and MIS 2. We correlate the significant 'Fleuve Manche' activity, detected during MIS 6 and MIS 2, with the extensive Saalian (Drenthe Substage) and the Weichselian glaciations, respectively, confirming that the major Elsterian glaciation precedes the glacial MIS 10. In detail, massive 'Fleuve Manche' discharges occurred at ca 155 ka (mid-MIS 6) and during Termination I, while no significant discharges are found during Termination II. It is assumed that a substantial retreat of the European ice sheet at ca 155 kyr, followed by the formation of ice-free conditions between the British Isles and Scandinavia until Termination II, allowed meltwater to flow northwards through the North Sea basin during the second part of the MIS 6. We assume that this glacial pattern corresponds to the Warthe Substage glacial maximum, therefore indicating that the data presented here equates to the Drenthe and the Warthe glacial advances at ca 175-160 ka and ca 150-140 ka, respectively. Finally, the correlation of our records with ODP site 980 reveals that massive 'Fleuve Manche' discharges, related to partial or complete melting of the European ice masses, were synchronous with strong decreases in both the rate of deep-water formation and the strength of the Atlantic thermohaline circulation. 'Fleuve Manche' discharges over the last 350 kyr probably participated, with other meltwater sources, in the collapse of the thermohaline circulation by freshening the northern Atlantic surface water.