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Selected AbstractsSexual size dimorphism in the two spot ladybird beetle Adalia bipunctata: developmental mechanism and its consequences for matingECOLOGICAL ENTOMOLOGY, Issue 4 2002Hironori Yasuda Abstract ,1. The literature on ladybirds indicates that males are consistently smaller than females but take the same length of time to complete their development. Rearing Adalia bipunctata at 20 and 25 °C confirmed that protandry cannot account for sexual size dimorphism in this species, nor can a difference in egg size. 2. Female larvae consumed more food and had a higher relative growth rate in the fourth instar than did male larvae. 3. When food is limited, small males appear to be more successful at mating than are large males. 4. To account for these results, it is hypothesised that the gonads of male larvae compete more strongly with the soma for resources and that this reduces the growth potential of the soma of male larvae relative to that of female larvae. The greater mating success of small males when food is limited supports the eat or mate hypothesis, which predicts that when food is limited small males will spend less time feeding and more time mating than will large males. [source] Controlled release experiments with nonylphenol in aquatic microcosmsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2003Gerd Pfister Abstract A method of controlled release of technical nonylphenol (tNP) was developed to simulate realistic exposure in ecotoxicological studies on aquatic organisms. The direct addition of tNP from an aqueous stock solution into 50 ml of water led to a concentration decrease of 80 to 90% weight/volume (w/v) from nominal values within 48 h. The inclusion of tNP in semipermeable low-density polyethylene (LDPE) lay-flat tubing (controlled-release devices [CRDs]) of different length allowed a continuous release into pure water at a rate of about 30 ,g/cm2/d. Using CRDs in aquaria containing 15 L of 63-,m-filtered lake water, eight different concentrations with maxima between 38.1 and 326.7 ,g/L were maintained for 11 d. During a second experiment in 15-L aquaria, five replicates of three concentrations were maintained using CRDs of the same length. Concentrations after 38 d varied between 0.1 and 6.7, 26.1 and 41.9, and 49.9 and 76.0 ,g/L. In aquatic microcosms containing 230 L of lake water, a natural plankton community, 50 L of sediment, and macrophytes, seven different tNP concentrations (maxima 11,120.1 ,g/L) were maintained over 45 d using CRDs of different length. They were replaced after 14 and 25 d because release of tNP was slower than predicted from laboratory experiments. Concentrations in the top 1-cm sediment layer were on average 19 times higher during the dosing period than concentrations in the water at the same time. In the sediments, different levels of applications led to concentrations that differed less distinctly than in the water. This method is suitable for exposing aquatic organisms continuously to constant, ecologically relevant concentrations of NP and represents an improvement over previous dosing methods in which exposure varied. [source] Childhood occipital epilepsy of Gastaut: A study of 33 patientsEPILEPSIA, Issue 2 2008Roberto Horacio Caraballo Summary Purpose: To characterize the electroclinical features and evolution of childhood occipital epilepsy of Gastaut (COE-G). Methods: Children with electroclinical criteria of COE-G were retrospectively identified and followed-up clinically, and with sleep and awake EEGs between 1990 and 2007. Results: We identified 33 patients with COE-G. In the same length of time, 201 children with Panayiotopoulos syndrome and 410 children with benign childhood epilepsy with centrotemporal spikes were registered. COE-G had a peak age at onset of 8.5 years. Visual manifestations were the most common ictal event. Ictal deviation of the eyes was frequent. Approximately half of the patients had migraine-like symptoms. In all patients the seizures occurred while awake, and 11 also had seizures during sleep. The majority of the patients had occipital spike-wave discharges when the eyes were closed that disappeared or attenuated when the eyes were opened. Prognosis was excellent in 80% of the cases. Conclusion: This study confirms the existence of COE-G, a rare but well-defined syndrome within the group of idiopathic focal epilepsies in childhood. [source] A Waveguide-Like Effect Observed in Multiwalled Carbon Nanotube BundlesADVANCED FUNCTIONAL MATERIALS, Issue 14 2010Shengyong Xu Abstract The delay time of nanosecond electromagnetic pulses is measured in multiwalled carbon nanotube (MWCNT) bundles and copper wires, with a length of up to 3,cm, as compared with that in standard coaxial cables of the same lengths. Under certain configurations, when the Cu core of a coaxial cable is replaced with a MWCNT bundle of the same length, the measured delay time of a pulsed signal is shortened. The difference between the delay time measured for a device with a Cu core and that of a device with a MWCNT bundle of the same length increases with the length of the samples. The results imply that, compared with Cu wires, MWCNT bundles may be more efficient in guiding the transmission of high-frequency signals along their longitudinal axis, showing a waveguide-like effect. [source] Accuracy of the Justy II Apex locator in determining working length in simulated horizontal and vertical fracturesINTERNATIONAL ENDODONTIC JOURNAL, Issue 3 2004M. Azabal Abstract Aim, To study the effectiveness of an electronic apex locator (EAL; Justy II; Yoshida Dentcraft, Tokyo, Japan) in locating simulated horizontal and vertical fractures in single roots. Methodology, An EAL was used to measure the distance within the canal of horizontal (n = 31) and vertical (n = 31) fractures, created with a disk in single-rooted teeth. Accuracy of the EAL was evaluated by comparing the measurements with those made using a size 10 file. Data were analysed with the non-parametric Passing and Bablok method. Results, For simulated horizontal fractures, the EAL measured exactly the same length as a size 10 file, without constant or proportional errors. In vertical simulated fractures, the EAL measured (on average) with a constant error of 7.5 mm shorter than the size 10 file; the difference had a wide confidence interval (,72.3 to 2.6 mm). Conclusions, In this laboratory study, the Justy II EAL was able to determine accurately the position of simulated horizontal fractures, but was unreliable when measuring simulated vertical fractures. [source] Intrastrand foldamer crosslinking by reductive aminationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 4 2010Ronald A. Smaldone Abstract A series of m -phenylene ethynylene (mPE) foldamers were crosslinked in their helical conformation using a reductive amination-based strategy. This was accomplished by placing aldehyde moieties in the backbone of the oligomer at specific residues, which allowed a diamine crosslinker to covalently link the helical loops together. Three different foldamers with crosslinks placed at different locations in the backbone were synthesized and characterized by mass spectrometry, 1H NMR, and gel permeation chromatography. The effect of the crosslinking on the stability of the folded state was evaluated through solvent denaturation studies. These studies show a reduction in the oligomer's ability to unfold of up to 30% relative to an unmodified mPE oligomer of the same length in solvents that promote unfolding. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 927,935, 2010 [source] Direct synthesis of amphiphilic block copolymers from glycidyl methacrylate and poly(ethylene glycol) by cationic ring-opening polymerization and supramolecular self-assembly thereofJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2005Wei Huang Abstract Amphiphilic block copolymers composed of a hydrophilic poly(ethylene glycol) (PEG) block and a hydrophobic poly(glycidyl methacrylate) (PGMA) block were synthesized through cationic ring-opening polymerization with PEG as the precursor. The model reactions indicated that the reactivity of the epoxy groups was higher than that of the double bonds in the bifunctional monomer glycidyl methacrylate (GMA) under the cationic polymerization conditions. Through the control of the reaction time in the synthesis of block copolymer PEG- b -PGMA, a linear GMA block was obtained through the ring-opening polymerization of epoxy groups, whereas the double bond in GMA remained unreacted. The results showed that the molecular weight of the PEG precursor had little influence on the grafting of GMA, and the PGMA blocks almost kept the same length, despite the difference of the PEG blocks. In addition, the PGMA blocks only consisted of several GMA units. The obtained amphiphilic PEG- b -PGMA block copolymers could form polymeric core,shell micelles by direct molecular self-assembly in water. The crosslinking of the PGMA core of the PEG- b -PGMA micelles, induced by ultraviolet radiation and heat instead of crosslinking agents, greatly increased the stability of the micelles. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2038,2047, 2005 [source] Preparation of novel macromonomers and study of their polymerizationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 15 2004Guohua Deng Abstract Novel macromonomers of polystyrene and poly(tert -butyl acrylate) containing a methacryloyl group as a polymerizable unit and two chains of the same length were prepared in two steps: the synthesis of the precursors through the atom transfer radical polymerization of styrene and tert -butyl acrylate initiated by 1-hydroxymethyl-1,1-di[(2-bromoisobutyryloxy)methyl] ethane and the esterification of the hydroxyl group in the precursors with methacryloyl chloride. The molecular weight and polydispersity of the macromonomers were controllable because of the living nature of the atom transfer radical polymerization. Gel permeation chromatography, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and hydrolysis confirmed the structure of the novel macromonomers. The homopolymerization and copolymerization of the macromonomers were investigated to prepare branched copolymers in which two chains were grafted from every repeating unit. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3887,3896, 2004 [source] Study on conical columns for semi-preparative liquid chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 3-4 2003Ma Jiping Abstract The dynamic flow profiles and column efficiencies in conically shaped semi-preparative liquid chromatographic columns (inlet ID larger than outlet ID) with two different conical angles (7° and 15°) were studied. The dynamic flow profiles were studied by an on-column visualization method. Conical columns were compared with cylindrical column of the same length and internal volume. The results showed that the flow profile of a sample band in the conical column of 7° (50 mm×17 mm , 11 mm ID) was parabolic in shape. The sample band migrated slower in the wall region than in the central region, as in the cylindrical column (50 mm×14 mm ID). However, the sample band in the conical column of 15° (50 mm×20 mm , 7 mm ID) migrated slower in the central region than in the wall region, resulting in a reverse parabolic flow profile, in contrast to that in cylindrical column. This indicated that a flat flow profile might be realized in a conical column with a conical angle between 7° and 15°. The conical column of 15° had the highest column efficiency among the three columns under the same conditions. Compared with the cylindrical column packed with identical packing material, the conical column of 15° had 22%,45% higher column efficiency and 11%,27% higher peak height. [source] Experimental study of vascularized nerve graft: Evaluation of nerve regeneration using choline acetyltransferase activityMICROSURGERY, Issue 2 2001Makoto Iwai M.D. A comparative study of nerve regeneration was performed on vascularized nerve graft (VNG) and free nerve graft (FNG) in Fischer strain rats. A segment of the sciatic nerve with vascular pedicle of the femoral artery and vein was harvested from syngeneic donor rat for the VNG group and the sciatic nerve in the same length without vascular pedicle was harvested for the FNG group. They were transplanted to a nerve defect in the sciatic nerve of syngeneic recipient rats. At 2, 4, 6, 8, 12, 16, and 24 weeks after operation, the sciatic nerves were biopsied and processed for evaluation of choline acetyltransferase (CAT) activity, histological studies, and measurement of wet weight of the muscle innervated by the sciatic nerve. Electrophysiological evaluation of the grafted nerve was also performed before sacrifice. The average CAT activity in the distal to the distal suture site was 383 cpm in VNG and 361 cpm in FNG at 2 weeks; 6,189 cpm in VNG and 2,264 cpm in FNG at 4 weeks; and 11,299 cpm in VNG and 9,424 cpm in FNG at 6 weeks postoperatively. The value of the VNG group was statistically higher than that of the FNG group at 4 weeks postoperatively. Electrophysiological and histological findings also suggested that nerve regeneration in the VNG group was superior to that in the FNG group during the same period. However, there was no significant difference between the two groups after 6 weeks postoperatively in any of the evaluations. The CAT measurement was useful in the experiments, because it was highly sensitive and reproducible. © 2001 Wiley-Liss, Inc. MICROSURGERY 24:43,51 2001 [source] Multiple copies of cytochrome oxidase 1 in species of the fungal genus FusariumMOLECULAR ECOLOGY RESOURCES, Issue 2009SCOTT R. GILMORE Abstract Using data from published mitochondrial or complete genomes, we developed and tested primers for amplification and sequencing of the barcode region of cytochrome oxidase 1 (COX1) of the fungal genus Fusarium, related genera of the order Hypocreales, and degenerate primers for fungi in the subdivision Pezizomycotina. The primers were successful for amplifying and sequencing COX1 barcodes from 13 genera of Hypocreales (Acremonium, Beauveria, Clonostachys, Emericellopsis, Fusarium, Gliocladium, Hypocrea, Lanatonectria, Lecanicillium, Metarhizium, Monocillium, Neonectria and Stilbella), 22 taxa of Fusarium, and two genera in other orders (Arthrosporium, Monilochaetes). Parologous copies of COX1 occurred in several strains of Fusarium. In some, copies of the same length were detected either by heterozygous bases in otherwise clean sequences or in different replicates of amplification and sequencing events; this may indicate multiple transcribed copies. Other strains included one or two introns. Two intron insertion sites had at least two nonhomologous intron sequences among Fusarium species. Irrespective of whether the multiple copy issue could be resolved by sequencing RNA transcripts, developing a precise COX1 -based barcoding system for Fusarium may not be feasible. The overall divergence among homologous COX1 sequences obtained so far is rather low, with many species sharing identical sequences. [source] Cloning, sequence, and function analyses of giant panda (Ailuropoda melanoleuca) CD9 gene,MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 9 2008Yang Tang Abstract CD9 is a member of the tetraspanin family proteins and has recently been shown to be essential for sperm,oocyte fusion in mice. The giant panda (Ailuropoda melanoleuca) CD9 (gpCD9) cDNA was amplified for the first time by RT-PCR from ovary total RNA and cloned, sequenced and analyzed. The result revealed that the open reading frame (ORF) of gpCD9 was 681 bp, which has the same length as that of mouse. Sequence analysis and structure prediction displayed that the amino acid sequence of gpCD9 is over 80% identity to those of mammals with the conserved structures, including the four transmembrane domains (TM) and certain characteristic residues. The results of sperm,egg fusion experiments demonstrated that giant panda CD9 large extracellular loop (LEL) significantly inhibited (P,<,0.05) the mouse gamete fusion when the recombinant protein was added. However, when three amino acid residues TVT (173,175) of the gpCD9 were mutated to AAA, the large extracellular loop (LELM) of mutated protein was rarely inhibiting the gamete fusion of mice. Our results may be useful in improving an insight into understanding the potential mechanism of gamete fusion and genetic characteristics of giant panda. Mol. Reprod. Dev. 75: 1418,1425, 2008. © 2008 Wiley-Liss, Inc. [source] Immediate blood pressure-lowering effects of aerobic exercise among patients with chronic kidney diseaseNEPHROLOGY, Issue 7 2008SAMUEL A HEADLEY SUMMARY: Aim: The current study was designed to determine the effect of moderate-intensity aerobic exercise on blood pressure responses within the laboratory for 60 min post exercise and in the subsequent 24 h period in patients with chronic kidney disease. Methods: Twenty-four subjects with stages 2,4 chronic kidney disease (age = 54.5 ± 15.2 years, body mass index = 32.0 ± 5.9 kg/m2) on antihypertensive medication completed this study. In random counterbalanced order, subjects were asked to either walk for 40 min at 50,60% VO2peak (oxygen consumption) or, on a separate day, to sit quietly in the laboratory for the same length of time. Following exercise or the non-exercise period, blood pressure was taken at 10 min intervals for 60 min. Subjects then wore an ambulatory blood pressure monitor for the next 24 h. Results: Systolic blood pressure (mmHg) was reduced by 6.5 ± 10.8 compared with the pre-exercise baseline value (130.3 ± 21.1) in the laboratory after exercise and this was greater than after the control period (0.73 ± 10.3, P < 0.05). Diastolic blood pressure (mmHg) was reduced following exercise (2.5 ± 6.4) compared with the control period (2.1 ± 4.9, P < 0.05). The mean 24 h readings did not differ between exercise or non-exercise days. Conclusion: Acute aerobic exercise leads to reduced blood pressure for at least 60 min within the laboratory in chronic kidney disease patients. [source] Relationship between segment structures and elastic properties of segmented poly(urethane-urea) elastic fibersPOLYMER ENGINEERING & SCIENCE, Issue 11 2003Nori Yoshihara Studies on segmented poly(urethane-urea) (SPUU) elastic fibers having various segment structures were done in terms of elastic recovery and stress-strain relationship (S-S). Three kinds of segment structures were used: 1) the same composition having different sequences of segment units, 2) the same length of soft segments having different molecular weights of polyol, and 3) different segment structures having almost the same stress at 350% elongation. The SPUU elastic fibers having higher sequence numbers of both soft and hard segment units, that is, greater block structures, show better elastic recovery properties, especially delayed elastic recovery. The SPUU elastic fibers showing better elastic recovery take an optimum value for the number-average molecular weight (Mn) of soft segments jointed with urethane bonds. Here the optimum Mn depends on the molecular weight of polytetramethyleneglycol (PTMG) as a starting material. The hysteresis loss in S-S for the pre-elongation decreases with an increase of Mn of PTMG. The SPUU elastic fibers having greater block structures show lower stress with lower 2C1 and 2C1 + 2C2 of Mooney-Rivilin plot constants for elastic fibers having the same composition. This indicates a lower density of crosslinks for finite deformation. An increase of the urea bonds or the molar ratio of urea bond to urethane bond raises the stress. It is found that the polymerization process, as well as composition, is important for design structures of SPUU elastic fibers. [source] An experimental study of GFP-based FRET, with application to intrinsically unstructured proteinsPROTEIN SCIENCE, Issue 7 2007Tomoo Ohashi Abstract We have experimentally studied the fluorescence resonance energy transfer (FRET) between green fluorescent protein (GFP) molecules by inserting folded or intrinsically unstructured proteins between CyPet and Ypet. We discovered that most of the enhanced FRET signal previously reported for this pair was due to enhanced dimerization, so we engineered a monomerizing mutation into each. An insert containing a single fibronectin type III domain (3.7 nm end-to-end) gave a moderate FRET signal while a two-domain insert (7.0 nm) gave no FRET. We then tested unstructured proteins of various lengths, including the charged-plus-PQ domain of ZipA, the tail domain of ,-adducin, and the C-terminal tail domain of FtsZ. The structures of these FRET constructs were also studied by electron microscopy and sedimentation. A 12 amino acid linker and the N-terminal 33 amino acids of the charged domain of the ZipA gave strong FRET signals. The C-terminal 33 amino acids of the PQ domain of the ZipA and several unstructured proteins with 66,68 amino acids gave moderate FRET signals. The 150 amino acid charged-plus-PQ construct gave a barely detectable FRET signal. FRET efficiency was calculated from the decreased donor emission to estimate the distance between donor and acceptor. The donor,acceptor distance varied for unstructured inserts of the same length, suggesting that they had variable stiffness (persistence length). We conclude that GFP-based FRET can be useful for studying intrinsically unstructured proteins, and we present a range of calibrated protein inserts to experimentally determine the distances that can be studied. [source] On the bootstrap in cube root asymptoticsTHE CANADIAN JOURNAL OF STATISTICS, Issue 1 2006Christian Léger Abstract The authors study the application of the bootstrap to a class of estimators which converge at a nonstandard rate to a nonstandard distribution. They provide a theoretical framework to study its asymptotic behaviour. A simulation study shows that in the case of an estimator such as Chernoff's estimator of the mode, usually the basic bootstrap confidence intervals drastically undercover while the percentile bootstrap intervals overcover. This is a rare instance where basic and percentile confidence intervals, which have exactly the same length, behave in a very different way. In the case of Chernoff's estimator, if the distribution is symmetric, it is possible to bootstrap from a smooth symmetric estimator of the distribution for which the basic bootstrap confidence intervals will have the claimed coverage probability while the percentile bootstrap interval will have an asymptotic coverage of 1! A propos du bootstrap pour des estimateurs convergeant a la vitesse racine cubique Les auteurs étudient l'application du bootstrap à une classe d'estimateurs qui convergent à une vitesse et vers une loi non standard. Ils présentent un cadre théorique pour l'étude de son comportement asymptotique. Une simulation démontre que dans le cas d'un estimateur du mode de Chernoff, la probabilité de couverture de l'intervalle de confiance bootstrap de base est grandement inférieure au niveau prescrit, alors que celle des intervalles de type percentile dépasse le niveau prescrit. C'est un rare cas où les intervalles de confiance de base et percentile ont un comportement si différent malgré des longueurs identiques. Dans le cas de l'estimateur de Chernoff, si la distribution est symétrique, il est possible d'appliquer le bootstrap à partir d'un estimateur lisse et symétrique de la distribution qui mènera à des intervalles bootstrap de base dont la probabilité de couverture asymptotique sera la bonne, alors que celle de l'intervalle percentile convergera vers 1! [source] The AT-hook-containing proteins SOB3/AHL29 and ESC/AHL27 are negative modulators of hypocotyl growth in ArabidopsisTHE PLANT JOURNAL, Issue 1 2008Ian H. Street Summary SOB3, which encodes a plant-specific AT-hook motif containing protein, was identified from an activation-tagging screen for suppressors of the long-hypocotyl phenotype of a weak phyB allele, phyB-4. sob3-D (suppressor of phyB-4#3 dominant) overexpressing seedlings have shorter hypocotyls, and as adults develop larger flowers and leaves, and are delayed in senescence compared with wild-type plants. At the nucleotide level, SOB3 is closely related to ESCAROLA (ESC), which was identified in an independent activation-tagging screen. ESC overexpression also suppresses the phyB-4 long-hypocotyl phenotype, and confers an adult morphology similar to sob3-D, suggesting similar functions. Analysis of transgenic plants harboring SOB3:SOB3-GUS or ESC:ESC-GUS translational fusions, driven by their endogenous promoter regions, showed GUS activity in the hypocotyl and vasculature tissue in light- and dark-grown seedlings. A loss-of-function SOB3 allele (sob3-4) was generated through an ethyl methanesulfonate intragenic suppressor screen of sob3-D phyB-4 plants, and this allele was combined with a predicted null allele, disrupting ESC (esc-8), to examine potential genetic interactions. The sob3-4 esc-8 double mutant had a long hypocotyl in multiple fluence rates of continuous white, far-red, red and blue light. sob3-4 esc-8 phyB-9 and sob3-4 esc-8 cry-103 triple mutants also had longer hypocotyls than photoreceptor single mutants. In contrast, the sob3-4 esc-8 phyA-211 triple mutant was the same length as phyA-211 single mutants. Taken together, these data indicate that SOB3 and ESC act redundantly to modulate hypocotyl growth inhibition in response to light. [source] Difference in the Length of the Medial and Lateral Metacarpal and Metatarsal Condyles in Calves and Cows , A Post-Mortem StudyANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 6 2007S. Nacambo Summary Measurements were taken in the metacarpal and metatarsal bones in 42 calves and 10 dairy cows post-mortem to determine whether there are anatomical differences in bone length. Manual and digital measurements of various bone length parameters were taken. There was a significant difference in the mean length of the condyles of the metacarpal and the metatarsal bones in calves and cows, the lateral condyle being longer than the medial. In all but one metatarsal bone (98.8%), the lateral condyle was longer than the medial. In the metacarpal bones, the lateral condyle was longer in only 52.4% of the bones, in 21.2%, they had the same length and in 27.4% the medial condyle was longer. These intrinsic anatomical differences can help distinguish between the left and right metacarpal and metatarsal bones, for instance, in anatomical and archaeological studies. Knowledge of these differences might be useful for studies on digit function and on the possible predisposition of cattle to claw diseases in the lateral claws of the hind limbs. [source] K2[O(HgSO3)3], a new sulfitomercurate with an [OHg3] coreACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2008Matthias Weil The structure of dipotassium ,3 -oxido-tris[sulfitomercurate(II)], K2[O(HgSO3)3], is characterized by segregation of the K+ cations and complex [O(HgSO3)3]2, anions into layers parallel to (010). The anion has m symmetry and is a new example of a ,3 -oxido-trimercurate complex with a central [OHg3] core. This unit adopts the shape of a flat, almost trigonal, pyramid (mean O,Hg = 2.072,Å and mean Hg,O,Hg = 110.8°). The two independent Hg,S bonds have nearly the same length (mean Hg,S = 2.335,Å). Due to intermolecular O...Hg donor,acceptor interactions greater than 2.65,Å, the O,Hg,S fragments are slightly bent. The [KO9] coordination polyhedron of the K+ cation approaches a distorted tricapped trigonal prism with a [6+1+2] coordination. [source] Trend estimation of financial time seriesAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 3 2010Víctor M. Guerrero Abstract We propose to decompose a financial time series into trend plus noise by means of the exponential smoothing filter. This filter produces statistically efficient estimates of the trend that can be calculated by a straightforward application of the Kalman filter. It can also be interpreted in the context of penalized least squares as a function of a smoothing constant has to be minimized by trading off fitness against smoothness of the trend. The smoothing constant is crucial to decide the degree of smoothness and the problem is how to choose it objectively. We suggest a procedure that allows the user to decide at the outset the desired percentage of smoothness and derive from it the corresponding value of that constant. A definition of smoothness is first proposed as well as an index of relative precision attributable to the smoothing element of the time series. The procedure is extended to series with different frequencies of observation, so that comparable trends can be obtained for say, daily, weekly or intraday observations of the same variable. The theoretical results are derived from an integrated moving average model of order (1, 1) underlying the statistical interpretation of the filter. Expressions of equivalent smoothing constants are derived for series generated by temporal aggregation or systematic sampling of another series. Hence, comparable trend estimates can be obtained for the same time series with different lengths, for different time series of the same length and for series with different frequencies of observation of the same variable. Copyright © 2009 John Wiley & Sons, Ltd. [source] Comparison of the swimming performance of farmed and wild gilthead sea bream, Sparus aurataAQUACULTURE RESEARCH, Issue 5 2007Fatih Basaran Abstract Farmed gilthead sea bream, Sparus aurata, frequently escape from the sea cages and interact with wild populations. The impact of these interactions on the wild populations will depend, in part, on differences in performance of the bream. This study compared the swimming performance of the wild and farmed fish in a current channel. The absolute critical swimming speed (Ucrit) increased with increasing size while the relative Ucrit decreased. Even at the same length there were noticeable performance differences between the individuals. The wild sea bream have significantly higher (P<0.05) absolute Ucrit performance (0.86±0.01 m s,1) than the farmed fish (0.79±0.01 m s,1) and significantly higher (P<0.05) relative Ucrit performance (4.52±0.05 BL s,1) than the farmed fish (4.21±0.05 BL s,1). The present study suggests that cultured sea bream may not have the ability to compete with wild sea bream in native seawaters. [source] Quality of life compared during pharmacological treatments and clinical monitoring for non-localized prostate cancer: a randomized controlled trialBJU INTERNATIONAL, Issue 7 2004H.J. Green OBJECTIVES To investigate the effects of different management strategies for non-localized prostate cancer on men's quality of life and cognitive functioning. PATIENTS, SUBJECTS AND METHODS Men with prostate cancer were randomly assigned to one of four treatment arms: leuprorelin, goserelin, cyproterone acetate (CPA), or close clinical monitoring. In a repeated-measures design, men were assessed before treatment (baseline) and after 6 and 12 months of treatment. A community comparison group of men of the same age with no prostate cancer participated for the same length of time. The men were recruited from public and private urology departments from university teaching hospitals. All those with prostate cancer who were eligible for hormonal therapy had no symptoms requiring immediate therapy. In all, 82 patients were randomized and 62 completed the 1-year study, and of the 20 community participants, 15 completed the study. The main outcome measures were obtained from questionnaires on emotional distress, existential satisfaction, physical function and symptoms, social and role function, subjective cognitive function, and sexual function, combined with standard neuropsychological tests of memory, attention, and executive functions. RESULTS Sexual dysfunction increased for patients on androgen-suppressing therapies, and emotional distress increased in those assigned to CPA or close clinical monitoring. Compared with before treatment there was evidence of an adverse effect of leuprorelin, goserelin, and CPA on cognitive function. Conclusions In deciding the timing of androgen suppression therapy for prostate cancer, consideration should be given to potential adverse effects on quality of life and cognitive function. [source] Influence of implant taper on the primary and secondary stability of osseointegrated titanium implantsCLINICAL ORAL IMPLANTS RESEARCH, Issue 4 2004Dominic O'Sullivan Abstract Objectives: The study presented was designed to analyse the mechanical performance and the primary and secondary stability characteristics of endosseous titanium implants with 1° (EXP1) and 2° (EXP2) of taper when compared with the standard Brånemark design (Nobel Biocare AB, Gothenburg, Sweden). Materials and methods: One pair of 10 mm EXP1 and control implants were placed in the femoral condyles of six rabbits. Paired 6 mm EXP1 and control implants and 6 mm EXP2 and control implants were placed in the tibial metaphysis. The control implants used were 4 mm diameter standard Brånemark implants, the same length as the test implants. At placement, insertion torque (IT) and resonance frequency analysis (RFA) measurements were performed. Six weeks postoperatively when the animals were killed, RFA and removal torque (RT) measurements were made. Results: At placement, significantly higher IT was needed to insert the EXP implants compared with the controls. RFA values were significantly higher for EXP1 implants placed in the tibia but not in the femur. In pooling data from the femur and tibia there was a significant difference. The EXP2 implants failed to insert fully and demonstrated a lower RFA value than may have been expected due to the exposed threads, although this difference was not statistically significant. Conclusions: The results from the present study showed that 1° of taper results in a better primary stability compared with the standard Brånemark design. There was no evidence that the tapered design caused negative bone tissue reactions. All the implants gained in stability during the healing period. Résumé L'étude présente a été effectuée pour analyser la performance mécanique et les caractéristiques de stabilité primaire et secondaire d'implants endoosseux en titane avec un taper (fuselé) 1° (EXP1) et 2 (EXP 2) comparés au modèle ad modum Branemark® standard. Une paire d'implants contrôles et un EXP1 de 10 mm ont été placés dans les condyles fémoraux de six lapins. Des paires d'implants contrôles et EXP1 de 6 mm et des implants contrôles et EXP2 de 6 mm ont été placés dans les métaphyses tibiales. Les implants contrôles utilisés avaient un diamètre standard de 4 mm, la même longueur que les implants tests. Lors du placement, des mesures de force d'insertion (IT) et d'analyse de fréquence de résonnance (RFA) ont été effectuées. Six semaines après l'opération lorsque les animaux ont été euthanasiés, les mesures RFA et les forces d'enlèvement (RT) ont été relevées. Lors du placement un IT significativement plus important a été nécessaire pour insérer les implants EXP1 comparé au contrôle. Les valeurs RFA étaient significativement plus importantes pour les implants EXP1 placés dans le tibia mais pas dans le fémur. En rassemblant les données du fémur et du tibia il y avait une différence significative. Les implants EXP2 ne parvenaient pas àêtre insérés à fond et ont montré une valeur RFA inférieure qui n'était pas inattendue vu les filetages exposés bien que ces différences n'étaient pas statistiquement significatives. Les résultats de l'étude présente ont montré que le taper 1 résultait en une stabilité primaire supérieure comparé au modèle ad modum Branemark® standard. Il n'y avait aucun signe que ce nouveau modèle causait des réactions tissulaires osseuses négatives. Tous les implants ont gagné en stabilité durant leur période de guérison. Zusammenfassung Ziele: Die hier vorgestellte Studie hatte zum Ziel, das mechanische Verhalten und die Charakteristika von Primär- und Sekundärstabilität bei enossalen Implantaten mit einer Gewindeneigung von 1° (EXP1) und von 2° (EXP2) zu untersuchen. Man verglich die Daten mit dem Standarddesign von Brånemark (Nobel Biocare AB, Gothenburg, Schweden). Material und Methode: Man implantierte ein Päärchen von 10mm-Implantaten (EXP1 und Kontrollimplantat) in die Femurkondylen von 6 Kaninchen. Zwei weitere Päärchen von 6mm-Implantaten (EXP1 und Kontrollimplantat, sowie EXP2 und Kontrollimplantat) implantierte man in die Metaphyse der Tibia. Bei den Kontrollimplantaten handelte es sich um Standardtypen von Brånemark mit einem Durchmesser von 4 Millimetern und derselben Länge wie die Testimplantate. Bei der Implantation mass man die Kraft, die es zu Eindrehen der Implantate brauchte (IT) und führte Messungen mit der Resonanzfrequenzanalyse (RFA) durch. Sechs Wochen nach der Operation wurden die Tiere geopfert, die RFA erneut durchgeführt und anschliessend der Ausdrehwiderstand (RT) bestimmt. Resultate: Bei der Implantation brauchte es signifikant grössere IT um die EXP-Implantate einzusetzen, als bei den Kontrollimplantaten. Die RFA-Werte waren bei den EXP1-Implantaten, die in die Tibia geschraubt worden waren, signifikant höher. Dies gilt aber nicht für die in den Femur geschraubten Implantate. Wurden die Daten vom Femur mit denen der Tibia verglichen, so erkannte man signifikante Unterschiede. Die EXP2-Implantate konnten nicht vollständig inseriert werden und zeigten auch tiefere RFA-Werte, als man den freiliegenden Schraubenwindungen entsprechend erwarten könnte. Diese Unterschiede waren aber nicht statistisch signifikant. Zusammenfassung: Die Resultate dieser Studie zeigten, das Schraubenwindungen mit 1° Steigung verglichen mit dem Standarddesign von Brånemark eine bessere Primärstabilität erzielten. Man fand andererseits keine Beweise, dass sich dieses neue Design der Schraubenwindungen negativ auf die Reaktion des Knochengewebes auswirkt. Alle Implantate gewannen während in der Heilphase an Stabilität dazu. Resumen Objetivos: El estudio presentado se diseñó para analizar el rendimiento mecánico y las características de estabilidad primaria y secundaria de implantes endoóseos de titanio con 1o (EXP1) y 2o (EXP 2) de autoroscado al compararlos con el diseño estándar de Brånemark (Nobel Biocare AB, Gothenburg, Suecia). Material y Métodos: Se colocó una pareja de implantes de 10 mm EXP1 y de control en los cóndilos femorales de 6 conejos. Se colocaron pareja de implantes de 6 mm EXP1 y de control y de 6 mm EXP2 y de control en la metáfisis tibial. Los implantes de control utilizados fueron Brånemark estándar de 4 mm de diámetro. A la colocación, se llevaron a cabo mediciones del torque de inserción (IT) y del análisis de la frecuencia de resonancia (RFA). Los animales se sacrificaron a las seis semanas de la operación, y se tomaron medidas del torque de remoción (RT). Resultados: Al colocarse, se necesitó un IT significativamente mas alto para insertar los implantes EXP en comparación con los de control. Los valores RFA fueron significativamente mas altos para implantes EXP1 colocados en la tibia pero no en el fémur. Confrontando los datos del fémur y de la tibia apareció una diferencia significativa. Los implantes EXP2 fracasaron en insertarse completamente y demostraron un menor valor de RFA del que se podía esperar debido a la exposición de las roscas, aunque esta diferencia no fue estadísticamente significativa. Conclusiones: Los resultados del presente estudio mostraron que 1o de autoroscado resultan en una mejor estabilidad primaria comparada con el diseño estándar de Brånemark. No hubo evidencia de que el diseño de autoroscado causara reacciones negativas en el tejido óseo. Todos los implantes ganaron estabilidad durante el periodo de cicatrización. [source] A Waveguide-Like Effect Observed in Multiwalled Carbon Nanotube BundlesADVANCED FUNCTIONAL MATERIALS, Issue 14 2010Shengyong Xu Abstract The delay time of nanosecond electromagnetic pulses is measured in multiwalled carbon nanotube (MWCNT) bundles and copper wires, with a length of up to 3,cm, as compared with that in standard coaxial cables of the same lengths. Under certain configurations, when the Cu core of a coaxial cable is replaced with a MWCNT bundle of the same length, the measured delay time of a pulsed signal is shortened. The difference between the delay time measured for a device with a Cu core and that of a device with a MWCNT bundle of the same length increases with the length of the samples. The results imply that, compared with Cu wires, MWCNT bundles may be more efficient in guiding the transmission of high-frequency signals along their longitudinal axis, showing a waveguide-like effect. [source] | ||||||||||||||||||||||