bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molluscs production associated to lunar-tide cycle: a case study in Paraíba State under ethnoecology viewpoint
Authors: Nishida Alberto K , Nordi Nivaldo , Alves Rômulo RN 
Published: June 2006

Abstract
Molluscs have been for a long time a very important food resource for humans. Therefore, oysters, clams, and mussels are highly required at seafood markets. Like any commercial food, it is necessary that molluscs present good quality standards, concerning some criteria such as amount of meat and appearance. In bivalves, condition index or fattening index is considered a satisfactory method for estimating the amount of meat related to the shell cavity. Molluscs gatherers of Paraíba State coast, northeastern Brazil, state that molluscan meat production increases during spring tide (designated by them as maré de lançamento) in opposition to the meat decrease which happens during neap tide (maré de quebramento) (they are designated technically in Portuguese as maré de sizígia and maré de quadratura, respectively). Weperformed a survey on the production of unha-de-velho or 'oldman'snail' (Tagelus plebeius) caught by molluscs gatherers in the estuary of River Paraíba do Norte, by observing locally their work, applying questionnaires, searching for a possible scientific relation of that molluscs condition to the gatherers empirical statement. Thus, we estimatedthe molluscs condition index through the method of solids percentage determination. We studied their work and the molluscs condition index during a full lunar-tide cycle. Determinations were carried out between 2nd September and 20th October, 1998, through 20 catches performed to obtain condition index from 400 bivalves. We observed that several biotic and abiotic ecological factors, namely reproduction cycle, biochemical components variations, animal size, and even parasitism, may affect the animal condition index. Despite this aspect, our present results confirmed a high overlapping (80%) of the condition index curve with lunar-tide cycle, in agreement with the gatherers statement. Although we recognize the need for formulating and testing other hypotheses, we consider a priori that the gatherers empirical assertion a unha tá gorda de acordocom a maré ('the "oldman's nail" is fat according to the tide', roughly translating) is justified by the observations here performed when the condition index increased during spring tide and decreased during neap tide.
Relaxin and β-estradiol modulate targeted matrix degradation in specific synovial joint fibrocartilages: progesterone prevents matrix loss
Authors: Hashem Gihan , Zhang Qin , Hayami Takayuki , Chen Jean , Wang Wei , Kapila Sunil 
Published: June 2006

AbstractRelaxin, a 6-kDa polypeptide hormone, is a potent mediator of matrix turnover and contributes to the loss of collagen and glycosaminoglycans (GAGs) from reproductive tissues, including the fibrocartilaginous pubic symphysis of several species. This effect is often potentiated by β-estradiol. We postulated that relaxin and β-estradiol might similarly contribute to the enhanced degradation of matrices in fibrocartilaginous tissues from synovial joints, which may help explain the preponderance of diseases of specific fibrocartilaginous joints in women of reproductive age. The objective of this study was to compare the in vivo effects of relaxin, β-estradiol, and progesterone alone or in various combinations on GAG and collagen content of the rabbit temporomandibular joint (TMJ) disc fibrocartilage, knee meniscus fibrocartilage, knee articular cartilage, and the pubic symphysis. Sham-operated or ovariectomized female rabbits were administered β-estradiol (20 ng/kg body weight), progesterone (5 mg/kg), or saline intramuscularly. This was repeated 2 days later and followed by subcutaneous implantation of osmotic pumps containing relaxin (23.3 μg/kg) or saline. Tissues were retrieved 4 days later and analyzed for GAG and collagen. Serum relaxin levels were assayed using enzyme-linked immunosorbent assay. Relaxin administration resulted in a 30-fold significant (p < 0.0001) increase in median levels (range, approximately 38 to 58 pg/ml) of systemic relaxin. β-estradiol, relaxin, or β-estradiol + relaxin caused a significant loss of GAGs and collagen from the pubic symphysis and TMJ disc and of collagen from articular cartilage but not from the knee meniscus. Progesterone prevented relaxin- or β-estradiol-mediated loss of these molecules. The loss of GAGs and collagen caused by β-estradiol, relaxin, or β-estradiol + relaxin varied between tissues and was most prominent in pubic symphysis and TMJ disc fibrocartilages. The findings suggest that this targeted modulation of matrix loss by hormones may contribute selectively to degeneration of specific synovial joints.
Mitochondrial mechanisms of cold adaptation in cod (Gadus morhuaL.) populations from different climatic zones
Authors: Lucassen M. , Koschnick N. , Eckerle L. G. , Pörtner H.-O. 
Published: June 2006

SUMMARYAdjustments in mitochondrial properties and capacities are crucial in acclimatization to seasonal cold as well as in evolutionary cold adaptation of marine ectotherms. To examine whether gene expression mechanisms contribute to different settings of aerobic capacities in populations of cod (Gadus morhua) along a latitudinal cline, maximum activities of key enzymes of mitochondrial metabolism and their respective mRNA levels were compared in white muscle and liver of cold (4°C) and warm (10°C) acclimated individuals from cod populations of the North Sea and the Barents Sea,respectively. In white muscle, cold acclimation caused a parallel increase in citrate synthase (CS) and in cytochrome c oxidase (COX) activities,but with a much larger effect in the cold eurythermal Arctic population. In liver, cold acclimation was accompanied by increments in CS activities, but differences between populations were minor. Overall COX activities in liver were not affected by cold acclimation, but were higher in the cold adapted population. In both populations increments in muscle CS capacities were tightly correlated with elevated mRNA levels, suggesting transcriptional control of citrate synthase levels in muscle. In liver, CS mRNA levels differed between populations but were not affected by cold acclimation, so that post-transcriptional control may contribute to elevated functional levels in this tissue. Mitochondrial-encoded COX2 mRNA levels were not limiting for functional activities in both tissues, in favour of post-transcriptional control or limitations by other transcripts of the COX complex. Altogether,the differentiation in gene expression between both populations was more strongly expressed at 4°C. The comparison of functional levels and transcript levels may reflect genetic differentiation at functional sites, in line with genetic differences between the two populations previously established by non-coding genetic markers.
2-hydroxyestradiol-17β-induced oocyte maturation: involvement of cAMP–protein kinase A and okadaic acid-sensitive protein phosphatases,and their interplay in oocyte maturation in the catfishHeteropneustes fossilis
Authors: Mishra A. , Joy K. P. 
Published: June 2006

SUMMARYIn Heteropneustes fossilis, in vitro incubation of postvitellogenic follicles with 2-hydroxyestradiol-17β(2-OHE2, 5 μmol l–1) decreased significantly the total cAMP level, concomitant with germinal vesicle breakdown (GVBD). The incubation of the follicles with cAMP or cAMP-elevating drugs[phosphodiesterase (PDE) inhibitors], such as IBMX(3-isobutyl-1-methyl-xanthine), theophylline and caffeine, inhibited the 2-OHE2-induced GVBD in a concentration-dependent manner. The magnitude of the response varied: both cAMP and IBMX were effective at all concentrations (0.1–2.0 mmol l–1), followed by theophylline (0.5–2.0 mmol l–1) and caffeine(1–2.0 mmol l–1). The protein kinase A (PKA) inhibitor H89 stimulated oocyte maturation in a concentration-dependent manner. However,when co-incubated with 2-OHE2 for 24 h it produced a biphasic effect: low concentrations (0.1 and 1.0 μmol l–1) did not alter the 2-OHE2-induced GVBD, but high concentrations (5 and 10μmol l–1) inhibited it. The incubation of the follicles with H89 lowered the inhibitory effect of IBMX on the 2-OHE2-induced GVBD. The incubation of the follicles with okadaic acid (OA), a protein phosphatase 1 and 2A inhibitor did not affect GVBD but when co-incubated with 2-OHE2, it enhanced the GVBD response. OA reversed the inhibitory effect of IBMX. The results suggest that OA may overcome the inhibition of 2-OHE2-induced GVBD by IBMX at a step distal to the cAMP–PKA pathway.
The origin of mean arterial and jugular venous blood pressures in giraffes
Authors: Mitchell Graham , Maloney Shane K. , Mitchell Duncan , Keegan D. James 
Published: June 2006

SUMMARY
Using a mechanical model of the giraffe neck and head circulation consisting of a rigid, ascending, `carotid' limb, a `cranial' circulation that could be rigid or collapsible, and a descending, `jugular' limb that also could be rigid or collapsible, we have analyzed the origin of the high arterial and venous pressures in giraffe, and whether blood flow is assisted by a siphon. When the tubes were rigid and the `jugular' limb exit was lower than the `carotid' limb entrance a siphon operated, `carotid' hydrostatic pressures became more negative, and flow was 3.3 l min–1 but ceased when the `cranial' and `jugular' limbs were collapsible or when the`jugular' limb was opened to the atmosphere. Pumping water through the model produced positive pressures in the `carotid' limb similar to those found in giraffe. Applying an external `tissue' pressure to the `jugular' tube during pump flow produced the typical pressures found in the jugular vein in giraffe. Constriction of the lowest, `jugular cuff', portion of the `jugular' limb showed that the cuff may augment the orthostatic reflex during head raising. Except when all tubes were rigid, pressures were unaffected by a siphon.
We conclude that mean arterial blood pressure in giraffes is a consequence of the hydrostatic pressure generated by the column of blood in the neck, that tissue pressure around the collapsible jugular vein produces the known jugular pressures, and that a siphon does not assist flow through the cranial circulation.
Partitioning locomotor energy use among and within muscles Muscle blood flow as a measure of muscle oxygen consumption
Authors: Marsh Richard L. , Ellerby David J. 
Published: June 2006

SUMMARYLinking the mechanics and energetics of locomotion in vertebrates has been hampered by a lack of information regarding the energy use of individual skeletal muscles in vivo. Here, we present a review of the available data concerning the relationship between the rates of skeletal muscle blood flow and oxygen consumption(V̇O2). In active muscle, during aerobically supported exercise, there is a linear relationship between these variables, irrespective of the muscle fiber type and intensity of exercise through most of the aerobic exercise range. We conclude that the rate of blood flow is the best available indicator of aerobic metabolic rate in multiple individual muscles or regions of muscles during locomotion. The practical considerations of using the injectable microsphere technique to measure muscle blood flow in this context are discussed.
Green land and blue sea: a coloured landscape in the orientation of the sandhopperTalitrus saltator(Montagu) (Amphipoda, Talitridae)
Authors: Ugolini Alberto , Somigli Silvia , Mercatelli Luca 
Published: June 2006

SUMMARYThe use of the landscape in the zonal recovery of Talitrus saltator (Montagu) was demonstrated in the past using natural and artificial landscapes. Here we evaluate the importance of colour in the landscape orientation of sandhoppers. Adult individuals of T. saltator were released in a Plexiglas bowl under the sun, with a view of an artificial landscape: a black cardboard strip or a pair of differently coloured filters, each occupying 180° of the horizon. Our results not only confirm the influence of the black and white artificial landscape-based compass cue on the zonal orientation of T. saltator, but also show that vision of a blue and green artificial landscape affects the direction of orientation; in fact, the orientation agreed with the directional indication of the landscape even when it contrasted with the sun compass indication. The same result was obtained with a blue–grey and green–grey landscape, but not with pairs of grey filters. Therefore, in the sandhoppers'visual world, a coloured landscape that matches the prevalent natural field colours greatly contributes to their directional choice.
Controlled Growth of Bi-Based Cuprate Whiskers
Authors: Matsubara Ichiro , Funahashi Ryoji , Miyaji Nobuhiro , Ueno Kazuo , Ishikawa Hiroshi 
Published: June 2006

Abstract
Cuprate whiskers with different crystal phases, Bi2Sr2CuOx (Bi-2201) and Bi4Sr8Cu5Ox (Bi-485), have been obtained by heating melt-quenched glass precursors. The crystal phase of the grown whiskers were controllable by changing the precursor composition and heating conditions. The Bi-2201 whiskers were identified to be of the R-phase, written in a general formula as Bi2+xSr2−xCuOy. The hole concentration of the as-grown Bi-2201 whiskers was also controlled from the underdoped to the overdoped state by changing the precursor composition. The temperature dependence of resistivity changed from a semiconducting to a metallic behavior corresponding to the hole concentration.
Synthesis and Properties of a Nitridomolybdenum(VI) Complex Having Benzenedithiolate Ligands. Effect of the Thiolate on the Activation of the Nitrido Ligand
Authors: Kondo Mitsuru , Oku Hiroyuki , Ueyama Norikazu , Nakamura Akira 
Published: June 2006

Abstract
A nitridomolybdenum(VI) complex having 1,2-benzenedithiolate (bdt2−) (NEt4)2[MoVIN(bdt)2Cl] was synthesized by the reaction of (NEt4)[MoVINCl4] with 2 equiv of Li2bdt in DMF/THF solution. This complex was characterized by measurements of the absorption, Raman, IR, and 14N NMR spectra. A lower Mo≡N band (1010 cm−1) in the Raman spectrum and the upfield shifted 14N NMR signal (−374 ppm) of the nitrido ligand compared to those of (NEt4)[MoVINCl4] (1055 cm−1 and −350 ppm) were observed, which strongly suggest the existence of a competitive π-electron donation from S (pπ) to Mo (dπ). The complex readily reacts with O2 or H2O to produce an oxomolybdenum(IV) complex [MoIVO(bdt)2]2−. This extremely air-sensitive complex shows a higher reactivity to O2 than that of (NEt4)[MoVINCl4]. It is concluded that the observed high reactivity is the result of a weakened Mo≡N bond by thiolate coordination.
Selective Adsorption of Metal Ions to Surface-Template Resins Prepared by Emulsion Polymerization Using 10-(p-Vinylphenyl)decanoic Acid
Authors: Koide Yoshifumi , Senba Hirofumi , Shosenji Hideto , Maeda Mizuo , Takagi Makoto 
Published: June 2006

Abstract
A monomer-type surfactant, 10-(p-vinylphenyl)decanoic acid (1), has been prepared and applied to an emulsifier for the preparation of surface-template resins. The hydrophobicity of 1 corresponded to that of C15H31COONa on the basis of the cmc values, while that of 1 on the emulsification corresponded to that of C12H25COONa. The monomers (DVB + St + 1) were copolymerized in a metal ion solution and the resulting polymers were evaluated for their surface-template effects. The suspension polymerization gave resins 0.08 mm in diameter and the adsorption of metal ions on Cu2+-imprinted resins attained equilibrium in 2 h. The surface-template effects based on the oriented 1 exceeded the inner-template resins in selective adsorption. On the other hand, the emulsion polymerization gave fine particles 200—300 nm in diameter. The resins showed excellent surface-template effects. The adsorption of metal ions was 50—100 times as much as that on the resins prepared by suspension polymerization (see and ). The metal-imprinted resins was 1.88 times more effective than the unimprinted resins, and the Zn2+-imprinted resins showed more effective adsorption for Zn2+ than for Cu2+ and for Ni2+. Such surface-template effects were also seen for Cu2+- and Ni2+-imprinted resins. The selectivity (Cu2+/Zn2+) from the mixture of both metal ions was 3.7 for the Cu2+-imprinted resins prepared at 0.25 mol% 1. Furthermore, the metal-imprinted resins could be used repeatedly.
One-Pot Synthesis of Unsymmetrical Ketones by the Reaction of Decacarbonyldimanganese with Two Kinds of Alkyllithiums
Authors: Yamamoto Hiroshi M , Sakurai Hidehiro , Narasaka Koichi 
Published: June 2006

Abstract
Decacarbonyldimanganese (Mn2(CO)10) is utilized as a phosgene equivalent for the one-pot preparation of unsymmetrical ketones. By a successive treatment of Mn2(CO)10 with two kinds of alkyllithiums, unsymmetrical ketones are obtained in high selectivity. Unsymmetrical α-diketones are generated when the above reaction is carried out in the presence of trimethyl phosphite and is quenched with N-bromosuccinimide.
Enzymatic Synthesis and Thermal Properties of a New Class of Polyphenol
Authors: Uyama Hiroshi , Kurioka Hideharu , Sugihara Junji , Kobayashi Shiro 
Published: June 2006

Abstract
Enzymatic oxidative polymerization of phenol has been carried out in an aqueous organic solvent using horseradish peroxidase as catalyst. The polymerization in a mixture of 1,4-dioxane and phosphate buffer (pH 7.0) (80 : 20 vol%) produced powdery polymeric materials, which were partly soluble in DMF and DMSO. The molecular weight of the DMF-soluble part determined by GPC was 3.5 × 104. Polymerization conditions have been investigated with respect to the polymer yield, solubility, and molecular weight. The solvent composition enormously affected the polymerization. The polymer structure was estimated by IR and NMR spectroscopies and found to contain a mixture of phenylene and oxyphenylene units. From TG analysis, the polymer was found to possess high thermal stability; 43 weight % of the polymer remained up to 1000 °C under nitrogen. DSC measurement showed no clear glass transition temperature or melting point.
Alcoholysis of Epoxides Catalyzed by Tetracyanoethylene and Dicyanoketene Acetals
Authors: Masaki Yukio , Miura Tsuyoshi , Ochiai Masahito 
Published: June 2006

Abstract
A typical π-acid tetracyanoethylene and capto-dative olefin dicyanoketene acetals were found to catalyze stereospecific alcoholysis of epoxides at the ambient temperature to 50 °C in good yields. Mildness and significant chemoselectivity of the catalysts were demonstrated by intactness of tetrahydropyranyl ether and ethylene acetal groups. A novel regioselectivity associated with anchimeric assistance of the ethereal group on the side chain was observed in the ring opening reaction of the 1,2-disubstituted epoxides.
CH-π Interaction as an Important Driving Force of Host–Guest Complexation. Further Evidence for the Selective Incorporation of Alkyl Groups in the Polyhydroxy Aromatic Cavity of Calix[4]resorcarene Host
Authors: Kikuchi Yasuaki , Aoyama Yasuhiro 
Published: June 2006

Abstract
The complexation of a calix[4]resorcarene host (2,8,14,20-tetraundecylcalix[4]arene-4,6,10,12,16,18,22,24-octol) with borneol in benzene or alkylbenzene was investigated by circular dichroism (CD) spectroscopy. The binding constants are dramatically solvent-dependent and decrease with respect to the substituents on the benzene ring in the order H &gt; methyl &gt; ethyl &gt; propyl &gt; butyl. The complexation of the same host with alkyl benzoates in limonene as a chiral hydrocarbon solvent was readily monitored by following their competitive inhibition effects on the CD intensities, reflecting the chiral host-solvent interaction. The binding constants for alkyl benzoates were again highly dependent on the alkyl groups, and changed in the order decyl &lt; hexyl &lt; methyl &lt; propyl ≈ pentyl &lt;&lt; butyl. There is thus an optimal chain length at butyl. These results provide further evidence for the selective incorporation of alkyl groups in the polyhydroxy aromatic cavity of the host.
Aerobic Oxidation of 3-Iodomethyl-Δ3-cephem-4-carboxylate to 3-Formyl-Δ3-cephem-4-carboxylate through 3-Hydroperoxymethyl-Δ3-cephem-4-carboxylate
Authors: Tanaka Hideo , Kikuchi Ryo , Torii Sigeru 
Published: June 2006

Abstract
Aerobic oxidation of p-methoxybenzyl 3-iodomethyl-8-oxo-7-phenylacetamido-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate (3-iodomethyl-7-phenylacetamido-Δ3-cephem-4-carboxylate) in N-methyl-2-pyrrolidone in the presence of phosphomolybdic acid mainly afforded the corresponding 3-formyl-Δ3-cephem-4-carboxylate, while similar aerobic oxidation in the presence of potassium iodide gave 3-hydroxymethyl-Δ3-cephem-4-carboxylate as a major product. 3-Hydroperoxymethyl-Δ3-cephem-4-carboxylate was isolated as a primary product in the aerobic oxidation, which was subsequently converted to either 3-formyl-Δ3-cephem-4-carboxylate by dehydration with phosphomolybdic acid or 3-hydroxymethyl-Δ3-cephem-4-carboxylate by reduction with potassium iodide.
Analysis of Facilitated Oxygen Transport in a Liquid Membrane of Hemoglobin
Authors: Chen Xue-si , Nishide Hiroyuki , Tsuchida Eishun 
Published: June 2006

Abstract
A liquid membrane containing bovine hemoglobin (Hb) as an oxygen carrier was prepared, and oxygen permeation through the membrane was measured by the electrochemical reduction of the permeated oxygen. The oxygen permeation was facilitated, as analyzed by a dual-mode model, to give permeation parameters of the membranes such as the diffusion coefficient (DHb) of the mobile carrier Hb and the solution-diffusion coefficient of oxygen (DO2). The facilitated permeation was the product of the Hb concentration ([Hb]0) and DHb in the membrane solution. DHb decreased with [Hb]0 or the solution viscosity; the maximum of the oxygen permeability (6.2 × 10−8 cm3(STP)cm cm−2s−1 cmHg−1 at the feed stream oxygen pressure of 0.54 cmHg) was observed at [Hb]0 = 12.8 g dl−1, where the facilitation factor and the oxygen/nitrogen permselectivity were ca. 10 and 18, respectively.
Apparent Molar Volume and Viscosity of N-Ethylpyridinium Iodide in Water
Authors: Panda B B , Dixit G , Behera B 
Published: June 2006

Abstract
The apparent molar volume and the viscosities of N-ethylpyridinium iodide in water at 25, 30, 35, and 40 °C are reported. The apparent molar volumes decrease with increasing temperature and obey Masson’s equation. The high values of φv° and Sv* indicate strong ion–ion interactions in water. φv° is linearly related to temperature. The viscosity data were analyzed by the Jones–Dole equation. The B values indicate greater solvation. The thermodynamic parameters of viscous flow and hydration number are discussed in terms of hydrophobic hydration and solvent-shared ion-pairs.
Ab Initio MO Calculations of NMR 15N–6Li Coupling Constants in Lithium Amide Monomers, Oligomers, and Mixed Aggregates with LiCl
Authors: Koizumi Terutake , Morihashi Kenji , Kikuchi Osamu 
Published: June 2006

Abstract
The NMR 15N–6Li coupling constants 1JNLi in LiNH2 and LiN(CH3)2 monomers and their oligomers and mixed aggregates with LiCl were calculated using ab initio self-consistent perturbation theory and the relation between the molecular structure and 1JNLi values was examined. The calculated 1JNLi values in the monomers are influenced by solvation and agree well with experimetal values when model solvent molecules are coordinated at the lithium atom. The calculated 1JNLi values in cyclic oligomers also agree well with experiment and support the structures derived from NMR experiments in solution. For the mixed trimer, (LiNH2)2LiCl, a ladder form was obtained as the most stable structure when the lithium atoms are solvated by two H2O or two NH3 molecules.