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NUMERICAL LAW OF REGRESSION OF CERTAIN SECONDARY SEX CHARACTERS

Pézard, A.
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 20/01/1921 Português
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The discrepancy in the relative variation of C and of θ led us to examine more closely the velocity of regression at the beginning in all the cases. At a given point of the curve, the velocity is furnished by the differential quotient of the length with reference to the time: See PDF for Equation At the beginning of regression, that is to say, at the time 0 See PDF for Equation We have tabulated the corresponding numerical values in the various instances: See PDF for Structure Although there is not absolute equality among the figures of the last column, one cannot fail to be struck by the fact that there is very little difference; in all instances they diverge much less than those of the first two columns, in which the variation is from 0.5 to 4.75 and from 1.95 to 12.0. We must admit, therefore, within rather wide limits, the constancy of the product of the time of regression and the constant C, whether the castration is intrapuberal or post-puberal. Geometrically, this result is represented by the constancy of the angle of the ordinate and the tangent to the parabola at the point of departure of the regression curve. Furthermore, it follows that the numerical law is represented not only by a parabola, but more exactly by segments of homothetic parabolas—an unexpected generalization...

Theoretical Series Elastic Element Length in Rana pipiens Sartorius Muscles

Matsumoto, Yorimi
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/05/1967 Português
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Assuming a two component system for the muscle, a series elastic element and a contractile component, the analyses of the isotonic and isometric data points were related to obtain the series elastic stiffness, dP/dls, from the relation, See PDF for Equation From the isometric data, dP/dt was obtained and shortening velocity, v, was a result of the isotonic experiments. Substituting (P0 - P)/T for dP/dt and (P0 - P)/(P + a) times b for v, dP/dls = (P + a) /bT, where P < P0, and a, b are constants for any lengths l ≤ l0 (Matsumoto, 1965). If the isometric tension and the shortening velocity are recorded for a given muscle length, l0, although the series elastic, ls, and the contractile component, lc, are changing, the total muscle length, l0 remains fixed and therefore the time constant, T. Integrating, See PDF for Equation the stress-strain relation for the series elastic element, See PDF for Equation is obtained; lsc0 - ls + lc0where lco equals the contractile component length for a muscle exerting a tension of P0. For a given P/P0, ls is uniquely determined and must be the same whether on the isotonic or isometric length-tension-time curve. In fact, a locus on one surface curve can be associated with the corresponding locus on the other.

Light Activates Output from Evening Neurons and Inhibits Output from Morning Neurons in the Drosophila Circadian Clock

Picot, Marie; Cusumano, Paola; Klarsfeld, André; Ueda, Ryu; Rouyer, François
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
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Animal circadian clocks are based on multiple oscillators whose interactions allow the daily control of complex behaviors. The Drosophila brain contains a circadian clock that controls rest–activity rhythms and relies upon different groups of PERIOD (PER)–expressing neurons. Two distinct oscillators have been functionally characterized under light-dark cycles. Lateral neurons (LNs) that express the pigment-dispersing factor (PDF) drive morning activity, whereas PDF-negative LNs are required for the evening activity. In constant darkness, several lines of evidence indicate that the LN morning oscillator (LN-MO) drives the activity rhythms, whereas the LN evening oscillator (LN-EO) does not. Since mutants devoid of functional CRYPTOCHROME (CRY), as opposed to wild-type flies, are rhythmic in constant light, we analyzed transgenic flies expressing PER or CRY in the LN-MO or LN-EO. We show that, under constant light conditions and reduced CRY function, the LN evening oscillator drives robust activity rhythms, whereas the LN morning oscillator does not. Remarkably, light acts by inhibiting the LN-MO behavioral output and activating the LN-EO behavioral output. Finally, we show that PDF signaling is not required for robust activity rhythms in constant light as opposed to its requirement in constant darkness...

THEORY AND MEASUREMENT OF VISUAL MECHANISMS : XI. ON FLICKER WITH SUBDIVIDED FIELDS

Crozier, W. J.; Wolf, Ernst
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 20/05/1944 Português
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In Vol. 27, No. 5, May 20, 1944, page 403, in the eighth line from the bottom of the page, the comma after "intensity" should be a semicolon. On page 413, in the second formula from the bottom of the page, for See PDF for Equation read See PDF for Equation On the same page, formula 2 should read See PDF for Equation On page 414, line 3, at the end of the line add "or" to read "of the level of I or of F." On page 422, in the first line below the figure legend, for "illuminate" read "illuminated." On page 430, line 22, for "lighteb dars" read "lighted bars."

Intersample fluctuations in phosphocreatine concentration determined by 31P-magnetic resonance spectroscopy and parameter estimation of metabolic responses to exercise in humans

Rossiter, H B; Howe, F A; Ward, S A; Kowalchuk, J M; Griffiths, J R; Whipp, B J
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Publicado em 15/10/2000 Português
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The ATP turnover rate during constant-load exercise is often estimated from the initial rate of change of phosphocreatine concentration ([PCr]) using 31P-magnetic resonance spectroscopy (MRS). However, the phase and amplitude characteristics of the sample-to-sample fluctuations can markedly influence this estimation (as well as that for the time constant (τ) of the [PCr] change) and confound its physiological interpretation especially for small amplitude responses.This influence was investigated in six healthy males who performed repeated constant-load quadriceps exercise of a moderate intensity in a whole-body MRS system. A transmit- receive surface coil was placed under the right quadriceps, allowing determination of intramuscular [PCr]; pulmonary oxygen uptake (V̇O2) was simultaneously determined, breath-by-breath, using a mass spectrometer and a turbine volume measuring module.The probability density functions (PDF) of [PCr] and V̇O2 fluctuations were determined for each test during the steady states of rest and exercise and the PDF was then fitted to a Gaussian function. The standard deviation of the [PCr] and V̇O2 fluctuations at rest and during exercise (sr and sw, respectively) and the peak centres of the distributions (xcr and xcw) were determined...

Structural variation and inhibitor binding in polypeptide deformylase from four different bacterial species

Smith, Kathrine J.; Petit, Chantal M.; Aubart, Kelly; Smyth, Martin; McManus, Edward; Jones, Jo; Fosberry, Andrew; Lewis, Ceri; Lonetto, Michael; Christensen, Siegfried B.
Fonte: Cold Spring Harbor Laboratory Press Publicador: Cold Spring Harbor Laboratory Press
Tipo: Artigo de Revista Científica
Publicado em /02/2003 Português
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Polypeptide deformylase (PDF) catalyzes the deformylation of polypeptide chains in bacteria. It is essential for bacterial cell viability and is a potential antibacterial drug target. Here, we report the crystal structures of polypeptide deformylase from four different species of bacteria: Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae, and Escherichia coli. Comparison of these four structures reveals significant overall differences between the two Gram-negative species (E. coli and H. influenzae) and the two Gram-positive species (S. pneumoniae and S. aureus). Despite these differences and low overall sequence identity, the S1′ pocket of PDF is well conserved among the four enzymes studied. We also describe the binding of nonpeptidic inhibitor molecules SB-485345, SB-543668, and SB-505684 to both S. pneumoniae and E. coli PDF. Comparison of these structures shows similar binding interactions with both Gram-negative and Gram-positive species. Understanding the similarities and subtle differences in active site structure between species will help to design broad-spectrum polypeptide deformylase inhibitor molecules.

Mapping the surface of Escherichia coli peptide deformylase by NMR with organic solvents

Byerly, Douglas W.; McElroy, Craig A.; Foster, Mark P.
Fonte: Cold Spring Harbor Laboratory Press Publicador: Cold Spring Harbor Laboratory Press
Tipo: Artigo de Revista Científica
Publicado em /07/2002 Português
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Identifying potential ligand binding sites on a protein surface is an important first step for targeted structure-based drug discovery. While performing control experiments with Escherichia coli peptide deformylase (PDF), we noted that the organic solvents used to solubilize some ligands perturbed many of the same resonances in PDF as the small molecule inhibitors. To further explore this observation, we recorded 15N HSQC spectra of E. coli peptide deformylase (PDF) in the presence of trace quantities of several simple organic solvents (acetone, DMSO, ethanol, isopropanol) and identified their sites of interaction from local perturbation of amide chemical shifts. Analysis of the protein surface structure revealed that the ligand-induced shift perturbations map to the active site and one additional surface pocket. The correlation between sites of solvent and inhibitor binding highlights the utility of organic solvents to rapidly and effectively validate and characterize binding sites on proteins prior to designing a drug discovery screen. Further, the solvent-induced perturbations have implications for the use of organic solvents to dissolve candidate ligands in NMR-based screens.

Structure and Activity of Human Mitochondrial Peptide Deformylase, a Novel Cancer Target

Escobar-Alvarez, Sindy; Goldgur, Yehuda; Yang, Guangli; Ouerfelli, Ouathek; Li, Yueming; Scheinberg, David A.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
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Peptide deformylase proteins (PDFs) participate in the N-terminal methionine excision pathway of newly synthesized peptides. We show that the human PDF (HsPDF) can deformylate its putative substrates derived from mitochondrial DNA-encoded proteins. The first structural model of a mammalian PDF (1.7 Å), HsPDF, shows a dimer with conserved topology of the catalytic residues and fold as non-mammalian PDFs. The HsPDF C-terminus topology and the presence of a helical loop (H2 and H3), however, shape a characteristic active site entrance. The structure of HsPDF bound to the peptidomimetic inhibitor actinonin (1.7 Å) identified the substrate-binding site. A defined S1′ pocket, but no S2′ or S3′ substrate-binding pockets, exists. A conservation of PDF–actinonin interaction across PDFs was observed. Despite the lack of true S2′ and S3′ binding pockets, confirmed through peptide binding modeling, enzyme kinetics suggest a combined contribution from P2′ and P3′ positions of a formylated peptide substrate to turnover.

The interactive presentation of 3D information obtained from reconstructed datasets and 3D placement of single histological sections with the 3D portable document format

de Boer, Bouke A.; Soufan, Alexandre T.; Hagoort, Jaco; Mohun, Timothy J.; van den Hoff, Maurice J. B.; Hasman, Arie; Voorbraak, Frans P. J. M.; Moorman, Antoon F. M.; Ruijter, Jan M.
Fonte: Company of Biologists Publicador: Company of Biologists
Tipo: Artigo de Revista Científica
Publicado em 01/01/2011 Português
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Interpretation of the results of anatomical and embryological studies relies heavily on proper visualization of complex morphogenetic processes and patterns of gene expression in a three-dimensional (3D) context. However, reconstruction of complete 3D datasets is time consuming and often researchers study only a few sections. To help in understanding the resulting 2D data we developed a program (TRACTS) that places such arbitrary histological sections into a high-resolution 3D model of the developing heart. The program places sections correctly, robustly and as precisely as the best of the fits achieved by five morphology experts. Dissemination of 3D data is severely hampered by the 2D medium of print publication. Many insights gained from studying the 3D object are very hard to convey using 2D images and are consequently lost or cannot be verified independently. It is possible to embed 3D objects into a pdf document, which is a format widely used for the distribution of scientific papers. Using the freeware program Adobe Reader to interact with these 3D objects is reasonably straightforward; creating such objects is not. We have developed a protocol that describes, step by step, how 3D objects can be embedded into a pdf document. Both the use of TRACTS and the inclusion of 3D objects in pdf documents can help in the interpretation of 2D and 3D data...

Circadian Period Integrates Network Information Through Activation of the BMP Signaling Pathway

Beckwith, Esteban J.; Gorostiza, E. Axel; Berni, Jimena; Rezával, Carolina; Pérez-Santángelo, Agustín; Nadra, Alejandro D.; Ceriani, María Fernanda
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
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Living organisms use biological clocks to maintain their internal temporal order and anticipate daily environmental changes. In Drosophila, circadian regulation of locomotor behavior is controlled by ∼150 neurons; among them, neurons expressing the PIGMENT DISPERSING FACTOR (PDF) set the period of locomotor behavior under free-running conditions. To date, it remains unclear how individual circadian clusters integrate their activity to assemble a distinctive behavioral output. Here we show that the BONE MORPHOGENETIC PROTEIN (BMP) signaling pathway plays a crucial role in setting the circadian period in PDF neurons in the adult brain. Acute deregulation of BMP signaling causes period lengthening through regulation of dClock transcription, providing evidence for a novel function of this pathway in the adult brain. We propose that coherence in the circadian network arises from integration in PDF neurons of both the pace of the cell-autonomous molecular clock and information derived from circadian-relevant neurons through release of BMP ligands.

A note on the probability distribution function of the surface electromyogram signal☆

Nazarpour, Kianoush; Al-Timemy, Ali H.; Bugmann, Guido; Jackson, Andrew
Fonte: Elsevier Science Publicador: Elsevier Science
Tipo: Artigo de Revista Científica
Publicado em /01/2013 Português
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► We recorded surface EMG signals with a biofeedback setup at 7 different contraction levels. ► We estimated the PDF, kurtosis and bicoherence index of the measured signals. ► We show that the EMG PDF at low contraction levels is super-Gaussian. ► At higher contraction forces, the EMG PDF tends to a Gaussian distribution.

Elastase, α1-Proteinase Inhibitor, and Interleukin-8 in Children and Young Adults with End-Stage Kidney Disease Undergoing Continuous Ambulatory Peritoneal Dialysis

Polańska, Bożena; Augustyniak, Daria; Makulska, Irena; Niemczuk, Maria; Jankowski, Adam; Zwolińska, Danuta
Fonte: Springer Basel Publicador: Springer Basel
Tipo: Artigo de Revista Científica
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Peritoneal dialysis is one of the main modality of treatment in end-stage kidney diseases (ESKD) in children. In our previous work in chronic kidney disease patients, in pre-dialyzed period and on hemodialysis, the neutrophils were highly activated. The aim of this study was to assess an inflammatory condition and neutrophil activation in ESKD patients undergoing continuous ambulatory peritoneal dialysis (CAPD). Thirteen CAPD patients without infection, both sexes, aged 2.5–24 years, and group of healthy subjects (C) were studied. For comparative purposes the conservatively treated (CT) group of ESKD patients was included. Neutrophil elastase in complex with α1-proteinase inhibitor (NE-α1PI; ELISA), α1-proteinase inhibitor (α1PI; radial immunodiffusion) and interleukin-8 (IL-8; ELISA) were measured in the blood samples from CAPD, CT, and C group and in the peritoneal dialysate fluid (PDF) samples of patients on CAPD. A significantly increased plasma NE-α1PI levels (median 176.5 μg/L, range 85.2–373.2 μg/L; p < 0.00005), serum IL-8 (median 18.6 pg/mL, range 15.73–35.28 pg/mL; p < 0.05), and slightly decreased serum α1PI (median 1,540 mg/L, range 1,270–1,955; p ≤ 0.05) compared to the control groups were found. There were no significant differences of analyzed parameters between CAPD and CT patients. The concentration ratio of NE-α1PI...

Convolutionless Nakajima–Zwanzig equations for stochastic analysis in nonlinear dynamical systems

Venturi, D.; Karniadakis, G. E.
Fonte: The Royal Society Publishing Publicador: The Royal Society Publishing
Tipo: Artigo de Revista Científica
Publicado em 08/06/2014 Português
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Determining the statistical properties of stochastic nonlinear systems is of major interest across many disciplines. Currently, there are no general efficient methods to deal with this challenging problem that involves high dimensionality, low regularity and random frequencies. We propose a framework for stochastic analysis in nonlinear dynamical systems based on goal-oriented probability density function (PDF) methods. The key idea stems from techniques of irreversible statistical mechanics, and it relies on deriving evolution equations for the PDF of quantities of interest, e.g. functionals of the solution to systems of stochastic ordinary and partial differential equations. Such quantities could be low-dimensional objects in infinite dimensional phase spaces. We develop the goal-oriented PDF method in the context of the time-convolutionless Nakajima–Zwanzig–Mori formalism. We address the question of approximation of reduced-order density equations by multi-level coarse graining, perturbation series and operator cumulant resummation. Numerical examples are presented for stochastic resonance and stochastic advection–reaction problems.

Cellular Requirements for LARK in the Drosophila Circadian System

Sundram, Vasudha; Ng, Fanny S.; Roberts, Mary A.; Millán, Carola; Ewer, John; Jackson, F. Rob
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/2012 Português
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RNA-binding proteins mediate posttranscriptional functions in the circadian systems of multiple species. A conserved RNA recognition motif (RRM) protein encoded by the lark gene is postulated to serve circadian output and molecular oscillator functions in Drosophila and mammals, respectively. In no species, however, has LARK been eliminated, in vivo, to determine the consequences for circadian timing. The present study utilized RNA interference (RNAi) techniques in Drosophila to decrease LARK levels in clock neurons and other cell types in order to evaluate the circadian functions of the protein. Knockdown of LARK in timeless (TIM)– or pigment dispersing factor (PDF)–containing clock cells caused a significant number of flies to exhibit arrhythmic locomotor activity, demonstrating a requirement for the protein in pacemaker cells. There was no obvious effect on PER protein cycling in lark interference (RNAi) flies, but a knockdown within the PDF neurons was associated with increased PDF immunoreactivity at the dorsal termini of the small ventral lateral neuronal (s-LNv) projections, suggesting an effect on neuropeptide release. The expression of lark RNAi in multiple neurosecretory cell populations demonstrated that LARK is required within pacemaker and nonpacemaker cells for the manifestation of normal locomotor activity rhythms. Interestingly...

A Homeostatic Sleep-Stabilizing Pathway in Drosophila Composed of the Sex Peptide Receptor and Its Ligand, the Myoinhibitory Peptide

Oh, Yangkyun; Yoon, Sung-Eun; Zhang, Qi; Chae, Hyo-Seok; Daubnerová, Ivana; Shafer, Orie T.; Choe, Joonho; Kim, Young-Joon
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 21/10/2014 Português
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Sleep, a reversible quiescent state found in both invertebrate and vertebrate animals, disconnects animals from their environment and is highly regulated for coordination with wakeful activities, such as reproduction. The fruit fly, Drosophila melanogaster, has proven to be a valuable model for studying the regulation of sleep by circadian clock and homeostatic mechanisms. Here, we demonstrate that the sex peptide receptor (SPR) of Drosophila, known for its role in female reproduction, is also important in stabilizing sleep in both males and females. Mutants lacking either the SPR or its central ligand, myoinhibitory peptide (MIP), fall asleep normally, but have difficulty in maintaining a sleep-like state. Our analyses have mapped the SPR sleep function to pigment dispersing factor (pdf) neurons, an arousal center in the insect brain. MIP downregulates intracellular cAMP levels in pdf neurons through the SPR. MIP is released centrally before and during night-time sleep, when the sleep drive is elevated. Sleep deprivation during the night facilitates MIP secretion from specific brain neurons innervating pdf neurons. Moreover, flies lacking either SPR or MIP cannot recover sleep after the night-time sleep deprivation. These results delineate a central neuropeptide circuit that stabilizes the sleep state by feeding a slow-acting inhibitory input into the arousal system and plays an important role in sleep homeostasis.

Partial dark-field microscopy for investigating domain structures of double-layer microsphere film

Heon Kim, Joon; Su Park, Jung
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em 11/05/2015 Português
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A lateral dislocation in a double-layer microsphere film is very difficult to identify because the constituent domains have the same two-dimensional crystalline orientation. Orientation-sensitive optical techniques cannot resolve this issue. Here, we demonstrate that partial dark-field (pDF) optical microscopy can be very effective in identifying this type of domain boundary and dislocation of a close-packed microsphere double-layer. Using the hexagonal symmetry of the close-packed microsphere film and the light-focusing property of microspheres, the partially blocked dark-field condenser can provide much higher contrast than other optical microscopy modes can in identifying the laterally dislocated domains. The former can also distinguish domains with different crystalline orientation by rotating the pDF stop. The simplicity of the pDF mode will make it an ideal tool for the structural study of close-packed double-layer microsphere films.

Potential Quarantine Treatments for White Sapote Infested with Caribbean Fruit Fly (Diptera: Tephritidae)

Hallman, Guy J.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
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White sapote, Casimiroa edulis Llave & Lex., was subjected to three quarantine treatments known to kill immature Caribbean fruit fly, Anastrepha suspense (Loew), in other fruits. Cold storage at 1 or 3°C for 15 and 18 d, respectively, did not cause appreciable harm to white sapotes compared with fruits stored at the normal 7°C. Immersion of white sapotes in water at 43.3°C for 90 or 120 min or at 46°C for 60 or 90 min caused considerable pitting and decay and interfered with ripening. Fumigation with methyl bromide at 24 and 40 g/m3 (24 ± 1.0°C) gave a reddish hue to white sapote, interfered with ripening, and increased the rate of decay. Cold storage at 1°C for 2-12 d was examined for its effectiveness in killing Caribbean fruit fly immatures in white sapote. Dose-mortality data were analyzed using the normal, logistic, and Gompertz probability density functions (PDF). The logistic PDF gave unrealistically low estimates of probit 9 (99.9968%) mortality; estimates using Gompertz, log 10, seemed too high. The normal PDF and Gompertz, non log 10, gave reasonable estimates of probit 9.

Estimated PDFs of Climate System Properties Including Natural and Anthropogenic Forcings

Forest, Chris Eliot.; Stone, Peter H.; Sokolov, Andrei P.
Fonte: MIT Joint Program on the Science and Policy of Global Change Publicador: MIT Joint Program on the Science and Policy of Global Change
Tipo: Relatório Formato: 894323 bytes; application/pdf
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We present revised probability density functions (PDF) for climate system properties (climate sensitivity, rate of deep-ocean heat uptake, and the net aerosol forcing strength) that include the effect on 20th century temperature changes of natural as well as anthropogenic forcings. The additional natural forcings, primarily the cooling by volcanic eruptions, affect the PDF by requiring a higher climate sensitivity and a lower rate of deep-ocean heat uptake to reproduce the observed temperature changes. The estimated 90% range of climate sensitivity is 2.4 to 9.2 K. The net aerosol forcing strength for the 1980s decade shifted towards positive values to compensate for the now included volcanic forcing with 90% bounds of -0.7 to -0.16 W/m2. The rate of deep-ocean heat uptake is also reduced with the effective diffusivity, Kv, ranging from 0.25 to 7.3 cm2/s. This upper bound implies that many coupled atmosphere-ocean GCMs mix heat into the deep ocean (below the mixed layer) too efficiently.; Abstract in HTML and technical report in PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/).; This work was supported in part by the NOAA Climate Change Data and Detection Program with support from DOE...

New Building Blocks for Dual-Property Molecule-Based Magnets

Venneri, Shari
Fonte: Brock University Publicador: Brock University
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Two classes of compounds have been prepared and characterized as building blocks for chiral magnets and ferromagnetic conductors. In the fIrst project, the organic framework of a pentadentate, (N302) macro cycle has been synthetically modifIed to introduce phenyl substituents into its organic framework and the synthesis of four new [Fe(In(N302)(CN)2] complexes (I) - (IV) is presented. [Molecular diagram availble in pdf] This work represents the fIrst structural and magnetic studies of a family of spin crossover macrocycles that comprise of both structural and stereo-isomers. Magnetic susceptibility and Mossbauer data for the R,R-complex (I) is consistent with both a thermal and a light induced spin crossover transition. The X-ray data supports a change in geometry accompanying the thermal spin transition, from a high spin (HS) 7 -coordinate complex at room temperature to a low spin (LS) 5-coordinate complex at 100 K. The crystal structure ofthe racemic complex (III) reveals a HS, 7-coordinate complex at 200 K that undergoes no signifIcant structural changes on cooling. In contrast, the magnetic - susceptibility and Mossbauer data collected on a powder sample of the racemic complex are consistent with a LS complex. Finally, the meso complex (IV) was prepared and its structure and magnetic properties are consistent with a 5-coordinate LS complex that remains low spin...

Water control vs. sea-water intrusion, (FGS: Leaflet no.5)

Sherwood, C.B.; Grantham, R.G.
Fonte: Tallahassee, FL pub. for the Florida Geological Survey; Tallahassee, FL pub. for the Florida Geological Survey Publicador: Tallahassee, FL pub. for the Florida Geological Survey; Tallahassee, FL pub. for the Florida Geological Survey
Tipo: Artigo de Revista Científica Formato: 15 p., 13 fig. illus.; color
Publicado em //1966 Português
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Series: Florida Geological Survey. Leaflet; 5 revised ; Subjects: Salt, Broward County Florida; http://purl.fcla.edu/fcla/dl/UF00001173.pdf http://publicfiles.dep.state.fl.us/FGS/FGS%5FPublications/L/L5revSherwoodGrantham1966.pdf http://publicfiles.dep.state.fl.us/FGS/FGS%5FPublications/L/Leaflet5-rev1.pdf ; Call number: FGS Leaflet 5 rev