bluuebunny/crossref_metadata_2025 huggingface dataset:
Six-Sided Heptaporphyrin Array: Towards a Nano-Sized Cube
Authors: Langford Steven J. , Woodward Clint P.
Published: June 2004

A strategy in preparing a family of hexameric porphyrin cubes based on the interplay of Sn(IV)-O and Ru(II)-N interactions is described. In this first iteration, we have prepared the heptamer [SnIV(TPyP)·(4)2][Ru(CO)(TPP)]6 (4 = (E)-(3-(4-pyridyl)acrylate)) constituting a 5,10,15,20-tetra(4-pyridyl)porphyrin (TPyP) core and 5,10,15,20-tetraphenylporphyrin (TPP) faces and compared its formation by stepwise and "one-pot" strategies where up to nine components are assembled in a single step in a regiospecific manner. In one example, the heptamer is formed around the template [SnIV(TPyP)·(4)2] bearing pyridine groups in which the nitrogens radiate octahedrally along each vertex. The ability to modulate the axial vertex through choice of pyridine is also demonstrated. 1H NMR measurements on [SnIV(TPyP)·(4)2][Ru(CO)(TPP)]6 indicate that the protons on the core template are extremely shielded as a result of the anisotropy of the peripheral porphyrin units. Various NMR techniques, including NOESY experiments, have been used to characterise the heptamer in solution.
Selective Derivatization of Calix[4]arenes via Amino Groups Attached to the Wide Rim
Authors: Bogdan Anca , Vysotsky Myroslav O. , Böhmer Volker
Published: June 2004

A new strategy is proposed for the synthesis of tetraether derivatives of calix[4]arenes bearing at the wide rim nitro and phthalimido groups in well defined positions. Since both groups are precursors of amino functions, calix[4]arenes substituted by different N-acylamino residues are easily available in four steps. The essential steps during the synthesis of the precursor consist in the protection of amino groups by the formation of their phthalimides followed by ipso-nitration of the remaining tert-butylphenol ether units. This nitration occurs without side reactions at the phthalimido substituted units, in contrast to simple N-acyl derivatives.
Tuning of the Cavity of Water-Soluble Thiacalix[4]arene for the Control of Inclusion Ability Toward Water-Miscible Organic Molecules
Authors: Kon Noriyoshi , Iki Nobuhiko , Sano Yuichiro , Ogawa Satoshi , Kabuto Chizuko , Miyano Sotaro
Published: June 2004

Inclusion abilities of water-soluble thiacalix[4]arenetetrasulfonate (3) and mono-O-carboxymethylated derivatives 5 and 6 toward water-miscible organic molecules such as alcohols, ketones, and nitriles in water were investigated by 1H NMR. The limit chemical shift change of the guest upon inclusion in the host suggested that the hosts regioselectively encapsulate the guests from the side of aliphatic moiety. Large guests such as pentan-1-ol showed folding of the alkyl chain to be included inside the cavity. On the other hand, mono-O-substituted 6 included a guest molecule less deep in the cavity than 3 did. Binding constants (K) of 3 toward guest molecules increased with hydrophobicity of the guest, suggesting that hydrophobic effect plays a main role for the complexation. On the contrary, mono-O-carboxymethyl derivatives 5 and 6 showed the opposite dependency of stability on hydrophobicity; higher affinities toward less hydrophobic guests. Among the guests examined, the smallest entities such as CH3OH and CH3CN were best included in 5 with the highest binding constant ever reported (K > 102 M-1). It was concluded that introduction of the carboxymethyl group into one of the phenolic OH of thiacalix[4]arene led to tuning of the cavity shape for stereospecific inclusion of small guests. The tuning of cavity by the O-alkylation was actually confirmed by X-ray crystal analysis of a complex of 5 with diethyl ketone.
(Thio)Urea-Functionalized Cavitands as Excellent Receptors for Organic Anions in Polar Media
Authors: Oshovsky Gennady V. , Verboom Willem , Reinhoudt David N.
Published: June 2004

Ureidocavitand 1 and thioureidocavitand 2 bind in CH3CN organic anions such as acetate, propionate, butyrate, etc. with K values of 2-8 × 105 l mol-1 and 2-9 × 106 l mol-1, respectively, as was determined with isothermal microcalorimetry (ITC). Bringing together four (thio)urea binding sites on a molecular platform gives rise to about 2000 times higher binding constants, compared with those of the corresponding single binding sites. Glucose- and galactose-containing thioureidocavitands 5 and 6 bind acetate in 1:1 CH3CN/water with a K-value of 2.15 × 103 l mol-1.
Synthesis of Porphyrin Receptors Modified by Glycosylated Steroids
Authors: Zelenka Karel , Trnka Tomáš , Tišlerová Iva , Král Vladimír , Dukh Mykhaylo , Drašar Pavel
Published: June 2004

5,10,15,20-Tetrakis-[3α-(2,3,4,6-tetra-O-benzyl-β-D-glucopyranosyl)-5β-cholan-24-yl]porphyrin and 5,10,15,20-tetrakis-[3α-(2,3,4,6-tetra-O-benzyl-β-D-galactopyranosyl)-5β-cholan-24-yl]porphyrin were synthesized by condenzation of the respective steroid aldehydes and pyrrole-1-yl magnesium bromide.
SPATIAL DECAY BOUNDS IN THE CHANNEL FLOW OF AN INCOMPRESSIBLE VISCOUS FLUID
Authors: LIN CHANGHAO , PAYNE LAWRENCE E.
Published: June 2004

In this paper, we study the transient flow of an incompressible viscous fluid in a semi-infinite channel assuming adherence at the channel boundary. We show that under appropriate restrictions on the data if the fluid is initially at rest and the channel entrance velocity and/or channel width are sufficiently small, the solution will tend exponentially to a transient laminar flow as the distance form the entry section tends to infinity. In fact explicit exponential decay bounds are obtained.
SECOND QUANTIZED AUTOMORPHISMS OF THE RENORMALIZED SQUARE OF WHITE NOISE (RSWN) ALGEBRA
Authors: ACCARDI LUIGI , AMOSOV GRIGORI , FRANZ UWE
Published: June 2004

We determine the structure of the *-endomorphisms of the RSWN algebra, induced by linear maps in the 1-particle Hilbert algebra, introduce the RSWN analogue of the free evolutions and find the explicit form of the KMS states associated with some of them.
THE KOLMOGOROV EQUATION ASSOCIATED TO THE STOCHASTIC NAVIER–STOKES EQUATIONS IN 2D
Authors: BARBU VIOREL , DA PRATO GIUSEPPE , DEBUSSCHE ARNAUD
Published: June 2004

We consider a 2D Navier–Stokes equation with Dirichlet boundary conditions perturbed by a stochastic term of the form [Formula: see text], where Q is a non-negative operator and Ẇ is a spacetime white noise. We solve the corresponding Kolmogorov equation in the space L2(H,ν) where ν is an invariant measure and prove the "carré du champs" identity. The key tool are some sharp estimates on the derivatives of the solution. Our main assumption is that the viscosity is large compared with the norm of Q. As a byproduct, we give a new simple proof of the uniqueness of the invariant measure and obtain an existence result for a Hamilton–Jacobi equation related to a control problem.
POSITIVE DILATIONS OF PIECEWISE MONOTONIC MARKOV MAPS
Authors: ANTONIOU I. , GUSTAFSON K. , SHKARIN S. A.
Published: June 2004

We provide an explicit formula which gives natural extensions of piecewise monotonic Markov maps defined on an interval of the real line. These maps are exact endomorphisms and define chaotic discrete dynamical systems.
CAUCHY–DIRICHLET PROBLEM ASSOCIATED TO DIVERGENCE FORM PARABOLIC EQUATIONS
Authors: RAGUSA MARIA ALESSANDRA
Published: June 2004

In this note we study the Cauchy–Dirichlet problem related to a linear parabolic equation of second order in divergence form with discontinuous coefficients. Moreover we prove estimates in the space [Formula: see text], for every 1<p<∞.
Pulse-synchronous sympathetic burst power as a new index of sympathoexcitation in patients with heart failure
Authors: Oda Yoshitaka , Asanoi Hidetsugu , Ueno Hiroshi , Yamada Kunihiro , Joho Shuji , Kameyama Tomoki , Hirai Tadakazu , Nozawa Takashi , Takashima Shutaro , Inoue Hiroshi
Published: June 2004

The upper limit of incidence of muscle sympathetic neural bursts can lead to underestimation of sympathetic activity in patients with severe heart failure. This study aimed to evaluate the pulse-synchronous burst power of muscle sympathetic nerve activity (MSNA) as a more specific indicator that could discriminate sympathetic activity in patients with heart failure. In 54 patients with heart failure, the pulse-synchronous burst power at the mean heart rate was quantified by spectral analysis of MSNA. Thirteen patients received a central sympatholytic agent (guanfacine) for 5 days to validate the feasibility of this new index. Both burst incidence and plasma norepinephrine level showed no significant difference between patients in New York Heart Association functional class III (94 ± 6 per 100 heartbeats and 477 ± 219 pg/ml, respectively) and class II (79 ± 14 per 100 heartbeats and 424 ± 268 pg/ml, respectively). In contrast, the burst power was useful for discriminating patients in class III from those in class II (61 ± 8% vs. 39 ± 10%; P < 0.05). Inhibition of sympathetic nerve activity by guanfacine was more sensitively reflected by the change of burst power (−36 ± 25%) than by that of burst incidence (−12 ± 14%; P < 0.001). The sympathetic burst power reflects both burst frequency and amplitude independently of the absolute values and provides a sensitive new index for interindividual comparisons of sympathetic activity in patients with heart failure.
Anti-inflammatory effects of resveratrol in lung epithelial cells: molecular mechanisms
Authors: Donnelly Louise E. , Newton Robert , Kennedy Gina E. , Fenwick Peter S. , Leung Rachel H. F. , Ito Kazuhiro , Russell Richard E. K. , Barnes Peter J.
Published: June 2004

Resveratrol (3,4′,5-trihydroxystilbene) is a polyphenolic stilbene found in the skins of red fruits, including grapes, that may be responsible for some of the health benefits ascribed to consumption of red wine. Resveratrol has been shown to have antioxidant properties and can act as an estrogen agonist. This study examined the anti-inflammatory effects of resveratrol on human airway epithelial cells. Resveratrol and the related molecule quercetin, but not deoxyrhapontin, inhibited IL-8 and granulocyte-macrophage colony-stimulating factor release from A549 cells. Neither the estrogen receptor antagonist tamoxifen nor the glucocorticoid antagonist mifepristone altered the inhibitory effect of resveratrol. The mechanism of resveratrol action was investigated further using luciferase reporter genes stably transfected into A549 cells. Resveratrol and quercetin inhibited NF-κB-, activator protein-1-, and cAMP response element binding protein-dependent transcription to a greater extent than the glucocorticosteroid dexamethasone. These compounds also had no significant effect on acetylation or deacetylation of core histones. Resveratrol, but not estradiol or N-acetyl cysteine, inhibited cytokine-stimulated inducible nitric oxide synthase expression and nitrite production (IC50 = 3.6 ± 2.9 μM) in human primary airway epithelial cells. Resveratrol also inhibited granulocyte-macrophage colony-stimulating factor release (IC50 = 0.44 ± 0.17 μM), IL-8 release (IC50 = 4.7 ± 3.3 μM), and cyclooxygenase-2 expression in these cells. This study demonstrates that resveratrol and quercetin have novel nonsteroidal anti-inflammatory activity that may have applications for the treatment of inflammatory diseases.
Role for Raphe Magnus Neuronal Responses in the Behavioral Reactions to Colorectal Distension
Authors: Brink Thaddeus S. , Mason Peggy
Published: June 2004

The brain stem is necessary for the expression of behavioral reactions to noxious visceral inputs. Neurons in raphe magnus (RM) and the adjacent nucleus reticularis magnocellularis (NRMC) respond to visceral stimuli and can facilitate the behavioral reaction to visceral stimulation. To determine which RM and NRMC cells could play a role in generating the reaction to colorectal distension (CRD), the responses of RM and NRMC cells to multiple intensities of CRD were compared with simultaneously evoked cardiovascular and visceromotor reactions in halothane-anesthetized rats. Most neurons (89%) responded to CRD with one of three basic response patterns. For cells with a graded response pattern, the response magnitude increased with increasing stimulation intensity. For flat responding cells, the response magnitude was not different across suprathreshold stimulation intensities. Finally, neurons with a switch response pattern responded to low- and high-intensity CRD in opposing directions. Cells were either inhibited or excited by CRD in each of these categories. Responses of cells with both graded and switch response patterns were significantly correlated with CRD-evoked tachycardia, pressor reaction, and hunching. The activity of graded-responding cells have the greatest predictive value for CRD-evoked reactions. Flat-responding cells have nonlinear responses that may augment reactions to stimuli above the noxious threshold. Cells with switch type response patterns may contribute to differential reactions evoked by CRD stimuli within the noxious range. In sum, RM and NRMC neurons respond to CRD with a variety of patterns, each of which may contribute to the sculpting of CRD reactions in different ways.
A parallel Cholesky algorithm for the solution of symmetriclinear systems
Authors: Khazal R. R. , Chawla M. M.
Published: June 2004

For the solution of symmetric linear systems, the classical
Cholesky method has proved to be difficult to parallelize. In the
present paper, we first describe an elimination variant of
Cholesky method to produce a lower triangular matrix which
reduces the coefficient matrix of the system to an identity
matrix. Then, this elimination method is combined with the partitioning method
to obtain a parallel Cholesky algorithm. The total
serial arithmetical operations count for the parallel algorithm
is of the same order as that for the serial Cholesky method. The
present parallel algorithm could thus perform with
efficiency close to 1 if implemented on a multiprocessor
machine. We also discuss the existence of the parallel
algorithm; it is shown that for a symmetric and positive definite
system, the presented parallel Cholesky algorithm is well defined
and will run to completion.
Logarithmic matrix transformations into Gw
Authors: Lemma Mulatu
Published: June 2004

We introduced the logarithmic matrix Lt and studied it as
mappings into ℓ and G in 1998 and 2000,
respectively. In this paper, we study Lt as mappings into
Gw.
Counting occurrences of 132 in an even permutation
Authors: Mansour Toufik
Published: June 2004

We study the generating function for the number of even (or odd)
permutations on n letters containing exactly r ≥ 0 occurrences
of a 132 pattern. It is shown that finding this function for a
given r amounts to a routine check of all permutations in
𝔖2r.
Edge‐disjoint Hamiltonian cycles in two‐dimensional torus
Authors: Bae Myung M. , Albdaiwi Bader F. , Bose Bella
Published: June 2004

The torus is one of the popular topologies for the
interconnecting processors to build high‐performance
multicomputers. This paper presents methods to generate
edge‐disjoint Hamiltonian cycles in 2D tori.
Serotonin modifies the sensitivity of the male silkmoth to pheromone
Authors: Gatellier Laureline , Nagao Takashi , Kanzaki Ryohei
Published: June 2004

Serotonin is known to modulate the response of neuronal populations in the primary olfactory center of the moth olfactory system, the antennal lobe. Here, we analyzed the effects of serotonin on the behavior related to the restricted pheromone olfactory pathway of the male silkmoth, Bombyx mori. In order to understand the effects of serotonin at the behavioral level, we applied serotonin (10-5 mol l-1,10-4 mol l-1 and 10-3 mol l-1) to the brain and found that 10-4 mol l-1 serotonin increases the sensitivity to female pheromone whereas 10-3 mol l-1 serotonin had the opposite effect. Levels of serotonin in the brain were determined using HPLC with electrochemical detection. Inhibitory effects were observed after applying the serotonin antagonists mianserin(10-4 mol l-1) and ketanserin (10-3 mol l-1). Additionally, we quantified the circadian variation of serotonin in the brain using HPLC with electrochemical detection. Further,this variation correlated well with a circadian variation of the male sensitivity to pheromone. These results show that the serotonin-related enhancement of neuronal responses at the antennal lobe level is expressed at the behavioral level as a modulation of pheromone sensitivity and that the circadian variation of serotonin levels in the brain correlates with changes in the moth's pheromone sensitivity.
Development and steroid regulation of RFamide immunoreactivity in antennal-lobe neurons of the sphinx mothManduca sexta
Authors: Schachtner Joachim , Trosowski Björn , D'Hanis Wolfgang , Stubner Stephan , Homberg Uwe
Published: June 2004

During metamorphosis, the insect nervous system undergoes considerable remodeling: new neurons are integrated while larval neurons are remodeled or eliminated. To understand further the mechanisms involved in transforming larval to adult tissue we have mapped the metamorphic changes in a particularly well established brain area, the antennal lobe of the sphinx moth Manduca sexta, using an antiserum recognizing RFamide-related neuropeptides. Five types of RFamide-immunoreactive (ir) neurons could be distinguished in the antennal lobe, based on morphology and developmental appearance. Four cell types (types II–V, each consisting of one or two cells) showed RFamide immunostaining in the larva that persisted into metamorphosis. By contrast, the most prominent group (type I), a mixed population of local and projection neurons consisting of about 60 neurons in the adult antennal lobe, acquired immunostaining in a two-step process during metamorphosis. In a first step, from 5 to 7 days after pupal ecdysis, the number of labeled neurons reached about 25. In a second step, starting about 4 days later, the number of RFamide-ir neurons increased within 6 days to about 60. This two-step process parallels the rise and fall of the developmental hormone 20-hydroxyecdysone (20E) in the hemolymph. Artificially shifting the 20E peak to an earlier developmental time point resulted in the precocious appearance of RFamide immunostaining and led to premature formation of glomeruli. Prolonging high 20E concentrations to stages when the hormone titer starts to decline had no effect on the second increase of immunostained cell numbers. These results support the idea that the rise in 20E, which occurs after pupal ecdysis, plays a role in the first phase of RFamide expression and in glomeruli formation in the developing antennal lobes. The role of 20E in the second phase of RFamide expression is less clear, but increased cell numbers showing RFamide-ir do not appear to be a consequence of the declining levels in 20E that occur during adult development.
Mechanical energy in toddler gait A trade-off between economy and stability?
Authors: Hallemans Ann , Aerts Peter , Otten Bert , De Deyn Peter P. , De Clercq Dirk
Published: June 2004

Mechanical energy expenditure was investigated in children who are just learning to walk and compared with adult mechanical energy expenditure during walking. First, we determined whether the inverted pendulum (IP) mechanism of energy exchange was present in toddlers. It seems that new walkers partially make use of this energy saving mechanism, but it is less efficient than in adults. The reduced recovery values (R=40% at optimal speeds in toddlers compared to 70% in adults) can be explained by their low self-selected walking speed in combination with their tossing gait (large vertical oscillations of the body) and by the observation that during as much as 25–50% of the gait cycle kinetic and potential energy are oscillating in-phase.

The second step was to calculate positive external mechanical work(Wext). Since the IP mechanism is less efficient in toddlers, more mass-specific positive work has to be performed to lift and accelerate the centre of mass than in adults walking at the same speed, even when differences in body size are taken into account.

The amount of positive internal work (Wint,k) necessary to move the body segments relative to the centre of mass was the third parameter we calculated. In toddlers Wint,k is largely determined by the kinetic energy of the lower limb. Compared to adults,toddlers have to perform less mass-specific work per unit distance to accelerate the body segments since the upper body is kept relatively stiff during walking and there is no arm swing.

Apart from work performed on the centre of mass and work performed to move the body segments relative to the centre of mass, when walking some work is also performed during double contact as both legs are pushing against each other. Two methods were used to calculate this amount of work, both leading to the same conclusions. Mass-specific work during double contact is small in toddlers compared to adults because of their low walking speed.

Finally the total amount of mechanical work performed in toddlers was compared to the work production observed in adults. Wextseems to be the major determinant for total mechanical energy expenditure. At intermediate froude numbers work production is comparable between adults and toddlers, but at low and high froude numbers Wtotincreases due to the steep increases in Wext. Despite the fact that mechanical work requirements in toddler gait are underestimated if work during double contact is not taken into account, it is not a major determinant of the energy cost of walking.
Spectral properties of myoelectric signals from different motor units in the leg extensor muscles
Authors: Wakeling James M. , Rozitis Antra I.
Published: June 2004

Myoelectric signals measured using intramuscular electromyograms (EMGs) in animals have shown that faster motor units generate higher frequencies in their power spectra. However, evidence to relate myoelectric frequency and motor unit type from the surface electromyograms typically measured from man have remained elusive. The purpose of this study was to determine if spectral properties from surface EMG could be related to the different motor units in the muscles of the leg extensors in man. Reflex experiments (both tendon tap and electrically stimulated) and graded isometric contractions were used to generate muscle contractions with different patterns of motor unit recruitment. EMG was recorded from the vastus lateralis and medialis, rectus femoris, medial and lateral gastrocnemius and soleus muscles. The EMGs were resolved into their intensities in time–frequency space using wavelet techniques. The intensity spectra were calculated for the reflex responses and for different contractile forces. The spectra were compared using principle component analyses and ANCOVA. Electrical stimulation can result in preferentially faster motor units being recruited, and in this study resulted in higher myoelectric frequencies than for the stretch reflex. During ramped contractions the motor units are recruited in an orderly fashion from slow to fast. As the faster motor units were recruited then higher frequency components appeared within the myoelectric intensity spectra. For all muscles tested there were significant correlations between the stage in contraction and the EMG frequency. Both approaches demonstrated higher frequency components in the myoelectric spectra when the faster motor units could be assumed to be active.
Pre-receptor profile of sensory images and primary afferent neuronal representation in the mormyrid electrosensory system
Authors: Gómez Leonel , Budelli Ruben , Grant Kirsty , Caputi Angel A.
Published: June 2004

Afferent responses to the fish's own electric organ discharge were explored in the electrosensory lobe of the mormyrid fish Gnathonemus petersii. In order to understand the neural encoding of natural sensory images,responses were examined while objects of different conductivities were placed at different positions along the skin of the fish, i.e. at different points within, and also outside, peripheral receptive fields. The presence of an object in the fish's self-generated electric field produces local modulation of transcutaneous current density. Measurement of the local electric organ discharge shows that object images formed at the electroreceptive sensory surface have an opposing center-surround, `Mexican hat' profile. This is a pre-receptor phenomenon intrinsic to the physical nature of the sensory stimulus that takes place prior to neural lateral inhibition and is independent of such central inhibition.

Stimulus intensity is encoded in the latency and number of action potentials in the response of primary afferent fibers. It is also reflected in changes in the amplitude and area of extracellular field potentials recorded in the deep granular layer of the electrosensory lobe. Since the object image consists of a redistribution of current density over the receptive surface,its presence is coded by change in the activity of receptors over an area much larger than the skin surface facing the object. We conclude that each receptor encodes information coming from the whole scene in a manner that may seem ambiguous when seen from a single point and that, in order to extract specific object features, the brain must process the electric image represented over the whole sensory surface.
Hypoxia tolerance and preconditioning are not additive in the trout(Oncorhynchus mykiss) heart
Authors: Gamperl A. Kurt , Faust Heather A. , Dougher Bekah , Rodnick Kenneth J.
Published: June 2004

Research has shown that the trout heart is normally hypoxia-sensitive, and that it can be preconditioned. However, we have identified a group of rainbow trout Oncorhynchus mykiss that shows a surprising degree of myocardial hypoxia tolerance. In this study, we used in situ hearts from these fish as a comparative model to examine whether the cardioprotective effects afforded by hypoxic adaptation and preconditioning are additive. In situ trout hearts were exposed to severe hypoxia (perfusate PO2 5–10 mmHg) in the absence and presence of a transient hypoxic pre-exposure (preconditioning). The four groups studied were: (1) control (no hypoxia); (2) 5 min of severe hypoxia;(3) 30 min of severe hypoxia; and (4) 5 min of severe hypoxia (hypoxic preconditioning) followed 20 min later by 30 min of severe hypoxia. 30 min of severe hypoxia significantly decreased maximum cardiac output and stroke volume by 15–30%. However, hypoxic preconditioning failed to confer any protection against post-hypoxic myocardial dysfunction. This work shows that the protection afforded by inherent myocardial hypoxia tolerance and preconditioning are not additive in this population of trout, and strongly suggests that the relationship between hypoxic adaptation and preconditioning in fishes resembles that of the neonatal/immature, not adult, mammalian heart. Further, our results (1) indicate that stretch (volume loading) and chronic exposure to low levels of adrenaline (15 nmol l-1) do not confer any protection against hypoxia-related myocardial dysfunction in this population, and (2) validate the use of the in situ trout heart as a comparative model for studying aspects of myocardial hypoxia tolerance and preconditioning in vertebrates.
One-step Route to Single-crystal γ-Mn3O4 Nanorods in Alcohol–Water System
Authors: Yang Baojun , Hu Hanmei , Li Cun , Yang Xiaogang , Li Qiaowei , Qian Yitai
Published: June 2004

A one-step low-temperature alcohol–water thermal route has been developed to synthesize single-crystal γ-Mn3O4 nanorods with diameters of 50–120 nm, and lengths of up to several tens micrometers. high-resolution transmission electron microscopic observations show that the axial direction of the as-prepared nanorods is perpendicular to the normal direction of the (101) lattice planes of the tetragonal γ-Mn3O4.
Novel Surface-modified Molecularly Imprinted Polymer Focused on the Removal of Interference in Environmental Water Samples
Authors: Watabe Yoshiyuki , Hosoya Ken , Tanaka Nobuo , Kubo Takuya , Kondo Takuya , Morita Masatosi
Published: June 2004

Uniformly sized molecularly imprinted polymers (MIPs) for bisphenol A (BPA) with immobilized intervals of functional monomers utilizing 4,4′-methylenebisphenol as a pseudo template have been prepared. The MIPs through surface modification for the removal of interference showed significant selectivity for BPA retention and removal performance for interference in actual environmental water samples as the HPLC stationary phase compared to those of ordinary MIPs. These MIPs were employed as pretreatment media of column switching HPLC.
Nitration of Aromatic Compounds with Nitric Acid Catalyzed by Ionic Liquids
Authors: Qiao Kun , Yokoyama Chiaki
Published: June 2004

Nitration of simple aromatic compounds with 62% nitric acid is successfully carried out under solvent-free condition in a biphasic mode in the presence of the Brønsted acidic ionic liquids; the only by-product is water and ionic liquids are capable of being reused without any separation.
Arrangement of Ferritin Molecules on a Gold Disk Array Fabricated on Highly Ordered Anodic Porous Alumina Substrate
Authors: Masuda Hideki , Hogi Hiromi , Nishio Kazuyuki , Matsumoto Futoshi
Published: June 2004

An ordered array of ferritin, in which the arrangement of ferritin coincided with the arrangement of Au disks, was prepared on Au nanodisk arrays fabricated on a highly ordered anodic porous alumina substrate. Selective adsorption of ferritin onto the Au disk by controlling the modification time and ferritin concentration in the modification solution was confirmed by scanning electron microscopy.
Dissolution of Phthalocyanines in Dense Carbon Dioxide and Its Solvatochromic Behavior under Pressureized Conditions
Authors: Kawanami Hajime , Ikushima Yutaka , Kobayashi Nagao
Published: June 2004

Metallophthalocyanines having alkoxy groups have been found to dissolve in dense carbon dioxide in the presence of small amount of cosolvent such as methanol or pyridine. The pressure dependence of the absorption maximum of these phthalocyanines can be used as an indicator for measuring solvent polarity.
Synthesis and Optical Properties of Novel Nickel Disulfide Dendritic Nanostructures
Authors: Luo Rui , Sun Xia , Yan Lifeng , Chen Wenming
Published: June 2004

Dendritic NiS2 nanostructures are successfully synthesized for the first time via the reaction between NiCl2·6H2O and CS2 in poly(MMA-co-EA) gel using γ irradiation.
Moderne Volumenvisualisierung (Modern Volume Visualization)
Authors: Pfister Hanspeter
Published: June 2004

Die Volumenvisualisierung hat sich in den letzten zehn Jahren zu einer unentbehrlichen Visualisierungstechnik für viele Anwendungsbereiche entwickelt. In diesem Beitrag präsentieren wir einen Überblick über moderne, hardwarebeschleunigte Methoden zur Visualisierung von Volumendaten: Raycasting, Texture-Slicing, Shear-Warp-Rendering und Splatting.
Medizinische Visualisierung: Methoden und Anwendungen in der Ausbildung und Therapieplanung (Visualization: Methods and Applications in Therapy Planning and Education)
Authors: Preim Bernhard , Peitgen Heinz-Otto
Published: June 2004

Die medizinische Visualisierung befasst sich mit der Darstellung und Exploration radiologischer Bilddatensätze. Zu den grundlegenden Aufgaben gehören die Exploration der patientenindividuellen Bilddaten, die Visualisierung baumartiger Strukturen, die Hervorhebung von Objekten, die quantitative Analyse sowie die virtuelle Resektion. Lösungsmöglichkeiten für diese Aufgaben werden anhand konkreter Fallbeispiele beschrieben.
Logik und Informatik (Logic and Computer Science)
Authors: Kreutzer Stephan , Schweikardt Nicole
Published: June 2004

Als eine ihrer wichtigsten theoretischen Grundlagen hat die Logik Bedeutung für fast alle Bereiche der Informatik. Wir wollen diese hier anhand der Bereiche Datenbanken, automatische Verifikation und Komplexitätstheorie erläutern und dabei die Fragestellungen und Ergebnisse unserer beiden Dissertationen vorstellen.
Rundheitsmessungen mit einem Diodenlaserinterferometer (Roundness Measurements with a Diode Laser Interferometer)
Authors: Burgarth Volker , Meiners-Hagen Karl , Abou-Zeid Ahmed
Published: June 2004

Stand der Technik bei Rundheitsmessungen sind zurzeit mechanisch antastende Systeme. Unter bestimmten Umständen kann die mechanische Antastung zu Abrieb oder Deformation des Prüflings führen. Mit einem neu entwickelten Interferometer und einem kommerziellen Formmessgerät wurden Rundheitsmessungen an verschiedenen Prüflingen berührungslos durchgeführt. Die Funktionsfähigkeit der interferometrischen Messmethode konnte für einen weiten Bereich von Rundheitsabweichung, Material und Oberflächenstruktur gezeigt werden. Zum Vergleich wurden die Prüflinge auch mit einem mechanischen Taster ausgemessen.
Simulationskammer für ein modifiziertes Senarmont-Verfahren (Simulation Chamber for a Modified Senarmont Measurement Method)
Authors: Kaufmann Siegfried , Schache Hannes , Beyer Horst
Published: June 2004

Automatische, berührungslose und Online-Messungen des Gangunterschiedes und der Doppelbrechung an laufenden, optisch anisotropen Proben (Fasern, Folien) können auch bei modernen Herstellungsverfahren falschfarbenfrei und schnell bei sehr hohen Gangunterschieden durchgeführt werden. Dazu dient ein von uns entwickeltes modifiziertes Senarmont-Mess-Verfahren. Die trotzdem noch auftretenden Probleme werden mit einer Simulationskammer untersucht, wobei insbesondere die Auswirkungen des Verdrehungswinkels bei Folien, die Wirkung des abgewinkelten Strahlenganges bei der berührungslosen Messung an Fasern und die Auswirkungen von Lageschwankungen der Fasern auf den Gangunterschied und die Doppelbrechung getestet werden.
Growth, Survival, and Body Composition of Juvenile Atlantic Sturgeon Fed Five Commercial Diets under Hatchery Conditions
Authors: King Kim
Published: June 2004

Growth and survival were evaluated for 1 year in juvenile Atlantic sturgeon Acipenser oxyrinchus (mean weight, 164.9 g) held at seasonal temperatures (6.4–16.9°C) and fed five commercially available feeds: Biokyowa (BK; control), Zeigler sturgeon (ZSD), Integral sturgeon (ISD), Atlantic salmon (ASD2–30), and Government Ration trout diet (GR7–30). During the 365-d study, the overall growth performance of the juvenile Atlantic sturgeon fed ZSD, ASD2–30, and ISD was equal to that of the fish fed the BK diet and superior to that of the fish fed GR7–30 (P < 0.05). The final mean weight was highest for the fish fed ZSD and lowest for the fish fed GR7–30. The fish fed the ZSD and BK diets were the only groups to continue gaining weight in winter (6.4–9.7°C). The differences in growth may be related to dietary levels or ingredient quality. Body moisture, body protein, and body fat were affected by diet type and seasonal temperature. Among the diets tested, ZSD and ASD2–30 produced the greatest growth at the lowest cost in juvenile Atlantic sturgeon held at ambient seasonal temperatures.
Adult Recoveries of Volitionally and Forced-Released Juvenile Coho Salmon
Authors: Appleby Andrew E , Tipping Jack M , Seidel Paul R
Published: June 2004

Test groups of coded-wire-tagged yearling coho salmon Oncorhynchus kisutch were either volitionally released or forcibly released for 3 years at two hatcheries. Results for the two release methods showed similar survivals for age-2 males (jacks) or age-3 fish. We suggest that volitional release could have benefits in feed savings and allow limited water to be redirected in the hatchery.
Collection, Removal, and Quantification of Eggs Produced by Rosy Red Fathead Minnows in Outdoor Pools
Authors: Clemment Troy , Stone Nathan
Published: June 2004

Eggs produced by rosy red fathead minnows Pimephales promelas held at four densities in 12 outdoor pools were collected and removed from substrate and had their numbers estimated. Adult fish were stocked at a sex ratio of 4:1 (females: males) and at densities of 5.1, 15.3, 25.4, or 35.6 fish/m2. Sodium sulfite (1.5–2.0%) was used to detach fathead minnow eggs from the spawning substrate. Egg numbers were estimated volumetrically based on an average (±SD) of 578 ± 34 eggs per milliliter. Mean daily egg numbers generally increased with fish density, and production ranged from 2,587 ± 2,999 to 9,595 ± 2,423 eggs/kg of broodfish. Averaging all treatments together for the 16-d period, over 6,000 eggs/d were collected per kilogram of broodfish. Based on this estimate, 500 kg of broodfish in a 1-ha pond would produce an average of 3 million eggs each day. Assuming an 80% hatching rate, this number of eggs would result in enough fry to stock a 0.5–1.0-ha pond. The results imply that an intensive production method consisting of harvesting eggs from ponds, indoor hatching, and subsequent fry stocking (as is now practiced for other baitfish species) could be feasible for fathead minnows.
Preliminary Assessment of Sex Inversion of Farmed Atlantic Salmon by Dietary and Immersion Androgen Treatments
Authors: Lee Peter , King Harry , Pankhurst Ned
Published: June 2004

Dietary and immersion treatments with the androgens 17α-methyltestosterone (MT) and 17α-methyldihydrotestosterone (MDHT) were assessed for their efficacy in the masculinization of Atlantic salmon Salmo salar. Dietary treatments with MT at 1 or 3 mg/kg food or MDHT at 1 mg/kg food for 800 degree-days resulted in 100% masculinization of all female stocks. Single or double immersion treatments of alevins in MDHT at 400 μg/L for 120 min during the period 0–28 d after median hatch resulted in significant masculinization. Immersion treatments were most effective when conducted more than 14 d after median hatch. Two immersion treatments 7 or 14 d apart resulted in masculinization levels of up to 100%, whereas single immersions yielded levels up to 77%. Immersion treatment resulted in the production of significantly more sex-inverted males with patent sperm ducts than did dietary treatment. The study shows that immersion treatments are simple and effective for androgen-induced masculinization of Atlantic salmon, that they are suitable for commercial-scale use in hatcheries, and that they offer advantages in production efficiency over dietary treatments.
Use of Hydrogen Peroxide during Incubation of Landlocked Fall Chinook Salmon Eggs in Vertical-Flow Incubators
Authors: Barnes Michael E , Gaikowski Mark P
Published: June 2004

Six different hydrogen peroxide treatment regimes were evaluated in a series of three trials with landlocked fall Chinook salmon Oncorhynchus tshawytscha eggs incubated in vertical-flow incubators. Six daily 15-min hydrogen peroxide treatment regimes (1,000 mg/L; 1,000 mg/L with a decrease to 500 mg/L during estimated blastopore formation; 2,000 mg/L; 2,000 mg/L with a decrease to 500 mg/L during estimated blastopore formation; 2,500 mg/L; and 2,500 mg/L with a decrease to 500 mg/L during estimated blastopore formation) were compared with daily 15-min treatments of 1,667 mg/L of formalin. Mortality at egg eye-up and fry hatch and from eye-up to hatch was significantly greater in eggs receiving the 2,500-mg/L hydrogen peroxide treatments throughout incubation and in those receiving 2,500 mg/L hydrogen peroxide with a decrease to 500 mg/L during blastopore formation than in either of the 1,000-mg/L hydrogen peroxide treatment regimes or the formalin-treated eggs in the first trial. No significant differences in mortality were observed among any of the treatments in the subsequent two trials with maximum hydrogen peroxide concentrations of 2,000 mg/L. Fungal infestations were observed primarily in the incubation trays treated at either of the 1,000-mg/L hydrogen peroxide regimens, as well as in those trays whose treatment concentrations were dropped to 500 mg/L during blastopore formation. Infestations were not observed in any of the formalin-treated trays. If minor fungal infestation is acceptable, then daily hydrogen peroxide treatments of 1,000 mg/L for 15 min would probably provide adequate fungal control compared with formalin usage.
Failure of a Plant-and-Krill-Based Diet to Affect the Performance of Yellowstone Cutthroat Trout Broodfish
Authors: Smith Mark A , Hubert Wayne A , Barrows Frederic T
Published: June 2004

We compared the performance of Yellowstone cutthroat trout Oncorhynchus clarki bouvieri broodfish when fed a diet with corn Zea mays gluten meal, wheat Triticum spp. gluten meal, and krill Euphausia superba protein sources relative to two fish meal diets. We hypothesized that the plant-and-krill-based diet would lead to a greater bioavailability of trace minerals and result in better broodfish condition, greater egg fertilization rates, increased survival of embryos to the swim-up stage, and increased egg mineral content. The three diets were fed to three replicate lots of 2-year-old, captive-reared fish for a 10-month period prior to spawning. None of the measured characteristics of broodfish condition differed significantly among diets. We found no significant differences among diets in rates of egg fertilization or survival of embryos to the swim-up stage. Manganese levels were lower in the eggs of fish fed one of the fish meal diets, but that was the only measure of egg content with a significant difference among diets. The experiment did not indicate that the plant-and-krill protein diet was better than fish-meal-based diets relative to the physiological condition of broodfish or the reproductive capabilities of Yellowstone cutthroat trout broodfish reared in captivity.
Effect of Daily Feed Intake on Feed Efficiency of Juvenile Channel Catfish
Authors: Li Menghe H , Manning Bruce B , Robinson Edwin H
Published: June 2004

Pond-raised channel catfish Ictalurus punctatus fed to satiation typically have lower feed efficiency (the ratio of weight gain to feed consumption) than fish fed a restricted ration. It is not clear whether the reduction in feed efficiency of fish fed to satiation is caused by wasted feed or by less efficient feed utilization. Two studies were conducted using 110-L flow-through aquaria to evaluate the relationship among the feed intake, growth rate, and feed efficiency of juvenile channel catfish. In experiment 1, 20 fish averaging 46 g were fed once daily at 0.5% to 3.0% of body weight (BW) or to satiation for 2 weeks. In experiment 2, 15 fish averaging 37 g were fed once daily at 1.0% to 3.0% BW or to satiation for 4 weeks. Fish in the satiation group were fed as much as they would consume within 40 min, and the remaining feed pellets were removed and counted to determine the amount of feed consumed. In both experiments, weight gain increased as feed intake increased. Feed efficiency improved as feed intake increased and peaked at feeding rates of 100% and 89% satiation for experiments 1 and 2, respectively. The daily feeding rates required to maintain a constant BW were about 0.5–0.8% BW. The results from this study indicated that under controlled conditions, channel catfish most efficiently utilized feed when fed to satiation or close to satiation (without feed waste). This suggests that the reduction in the feed efficiency of fish fed to satiation in ponds is probably caused by wasted feed rather than by less efficient feed utilization by the fish. Pond-raised channel catfish should be fed at a rate slightly below satiation without overfeeding to achieve optimum feed efficiency. Severe feed restriction may result in poor feed efficiency because a higher proportion of ingested feed would be used for maintenance in heavily stocked ponds.
Rearing of the Cauque Prawn under Laboratory Conditions
Authors: Arana-Magallón F C , Ortega-Salas A A
Published: June 2004

Postlarvae of the cauque prawn Macrobrachium americanum were reared for 4 months under laboratory conditions at 20°C and 33°C. Four hundred 50-d-old postlarvae were stocked into eight 70-L aquaria. A balanced commercial feed containing 40% protein was supplied daily at 9–20% of body weight during the first 2 months and at 3–5% of body weight during the final 2 months. Live brine shrimp Artemia spp. were also provided as food. The growth of the cauque prawns was greater at 33°C than at 20°C but did not differ significantly over the study period. Knowledge of cauque prawn rearing requirements under artificial conditions is important for the production of juveniles as stock for large-scale prawn culture.
Evaluation of the Natural Product SeaKleen for Controlling the Musty-Odor-Producing Cyanobacterium Oscillatoria perornata in Catfish Ponds
Authors: Schrader Kevin K , Rimando Agnes M , Tucker Craig S , Glinski Jan , Cutler Stephen J , Cutler Horace G
Published: June 2004

The cyanobacterium (blue-green alga) Oscillatoria perornata is the major cause of musty off-flavor in farm-raised channel catfish Ictalurus punctatus in western Mississippi. Currently, the only federally approved compounds for use as selective algicides in catfish aquaculture ponds in the southeastern United States are the herbicide diuron and copper-based products (e.g., copper sulfate). Due to environmental issues and the broad-spectrum toxicity of these synthetic algicides to nontarget organisms, there is a need for environmentally safe algicides for controlling O. perornata in catfish ponds. Laboratory bioassay screening of the natural product SeaKleen, a quinone-based biocide used to treat the ballast water from ships, found that it is selectively toxic towards O. perornata compared with the green alga Selenastrum capricornutum. Subsequently, efficacy testing of SeaKleen was performed using limnocorrals placed in catfish aquaculture ponds containing O. perornata blooms. Two studies were performed: a dose–response study and a single-effective-concentration study. For both studies, water samples were removed from inside the limnocorrals before and after the application of SeaKleen. These water samples were monitored for levels of the musty off-flavor compound 2-methylisoborneol (MIB), chlorophyll-a levels, and phytoplankton community structure. Results from both studies found that approximately 1.3 mg/L SeaKleen was effective in significantly reducing the levels of chlorophyll a and MIB compared with controls. In addition, the abundance of O. perornata and other predominant species of filamentous cyanobacteria were significantly reduced compared with controls. Green algae and diatoms were not significantly affected. Additional studies are needed to determine the potential of SeaKleen as a selective algicide in commercial catfish aquaculture.
Dietary Uptake of Polychlorinated Biphenyls (PCBs) by Rainbow Trout
Authors: Carline Robert F , Barry Patrick M , Ketola H George
Published: June 2004

The presence of detectable levels of polychlorinated biphenyls (PCBs) in commercially produced fish feed has raised a concern about the degree of biomagnification of these contaminants in hatchery-reared trout. Our objectives were to (1) define the relationship between concentrations of PCBs in fish feed and in fish tissue and (2) estimate the relative contributions of feed and hatchery supply water to PCB concentrations in fish. We conducted a 6-month feeding trial with fingerling rainbow trout Oncorhynchus mykiss fed commercial diets with four concentrations of PCBs: a low-PCB diet (69 ng/g); a typical commercial diet (126 ng/g); and the typical diet spiked with PCBs at two levels (220 and 280 ng/g). The concentrations of PCBs in fillets after 1 month were commensurate with those in the feeds and remained relatively stable for the next 5 months; mean PCB concentrations in fillets ranged from 54 to 94 ng/g. Low levels of PCBs were detected in the hatchery supply water. We used the concentrations of PCBs in the feeds, absorption rates of PCBs, and two different rates of PCB depuration to estimate the potential uptake of PCBs from supply water. When we used a low depuration rate (half-life = 219 d), the computed body burdens of PCBs could be entirely attributed to the feeds. When a high depuration rate (half-life = 66 d) was used, some uptake of PCBs from the supply water was likely, but most of the total body burden originated from the feeds. We concluded that rainbow trout fed a diet with 126 ng/g PCBs would have a PCB concentration of about 60 ng/g in their fillets, which is high enough to warrant issuance of a consumption advisory (no more than one meal of fish per week) under a protocol adopted by some Great Lakes states.