bluuebunny/crossref_metadata_2025 huggingface dataset:
Expanding Your Coverage of Neuroscience: An Interview with Michael Gazzaniga
Authors: Rasmussen Erin B.
Published: July 2006

Erin Rasmussen is an Assistant Professor in the Department of Psychology at Idaho State University where she teaches learning, behavioral pharmacology, senior seminar, and introductory psychology. She received her MS and PhD in experimental psychology (with a minor in behavioral pharmacology and toxicology) from Auburn University. She taught at the College of Charleston for 3 years before joining the faculty at Idaho State. Her past research involved examination of how prenatal exposure to heavy metals affects the behavior of offspring and the role of environmental enrichment in attenuating those effects. Currently, she is examining how prenatal food restriction affects food choices that lead to obesity.

Michael Gazzaniga, the David T. McLaughlin Distinguished University Professor at Dartmouth College, is a pioneer in the field of cognitive neuroscience. He received his PhD from California Institute of Technology in psychobiology, where he conducted his famous work with Roger Sperry on the split-brain phenomenon. His research has provided insights on functional lateralization and how the cerebral hemispheres communicate with one another. He has written more than 20 books, many for the lay audience, and has well over 100 publications, including book chapters, interviews, and monographs. Currently, he serves as Director for the Center of Cognitive Neuroscience at Dartmouth. He was elected president of the American Psychological Society in 2004. He manages a summer school program in cognitive neuroscience and conducts many visiting professor seminars.
Introductory Psychology Topics and Student Performance: Where's the Challenge?
Authors: Peck Andrew C. , Ali Rahan S. , Levine Max E. , Matchock Robert L.
Published: July 2006

Conventional wisdom is that some topics in introductory psychology are more difficult for students than others. Such wisdom seems reasonable given mismatches between students' and instructors' expectations and variations in both instructor expertise and student motivation across topical areas. Five instructors pooled students' exam performance data to investigate topical difficulty. Data showed that students performed better on questions about social psychology, memory, consciousness, and development than questions about biopsychology and emotion. Discussion includes possible explanations and considerations for course planning.
A Program for Improving Undergraduate Psychology Students' Basic Writing Skills
Authors: Fallahi Carolyn R. , Wood Rebecca M. , Austad Carol Shaw , Fallahi Hamid
Published: July 2006

We examined the effects of in-class writing instruction, practice, peer review, and feedback on writing skills of undergraduates enrolled in a general psychology course. We rated writing for grammar, writing style, mechanics, and American Psychological Association referencing style. Significant differences emerged on the 4 writing skill domains ( p< .001). Improvement occurred immediately for referencing, whereas other skills did not improve significantly until the 4th paper. The results show that teaching writing in content courses such as general psychology can yield significant improvement in students' writing. We believe that writing instruction by psychology professors is worth the time and effort to help undergraduate psychology students develop better writing skills.
Cognitive Dissonance or Revenge? Student Grades and Course Evaluations
Authors: Maurer Trent W.
Published: July 2006

I tested 2 competing theories to explain the connection between students' expected grades and ratings of instructors: cognitive dissonance and revenge. Cognitive dissonance theory holds that students who expect poor grades rate instructors poorly to minimize ego threat whereas the revenge theory holds that students rate instructors poorly in an attempt to punish them. I tested both theories via an experimental manipulation of the perceived ability to punish instructors through course evaluations. Results indicated that student ratings appear unrelated to the ability to punish instructors, thus supporting cognitive dissonance theory. Alternative interpretations of the data suggest further research is warranted.
A Hands-On Exercise Improves Understanding of the Standard Error of the Mean
Authors: Ryan Robert S.
Published: July 2006

One of the most difficult concepts for statistics students is the standard error of the mean. To improve understanding of this concept, 1 group of students used a hands-on procedure to sample from small populations representing either a true or false null hypothesis. The distribution of 120 sample means ( n =3) from each population had standard errors that closely approximated those of the theoretical sampling distributions, thereby illustrating how the Central Limit Theorem provides a standard error to use for hypothesis testing. Performance on an exam about the standard error of the mean was significantly better for the students who had completed this exercise than for students in a control group.
Teaching about Psychological Disorders: Using a Group Interviewing ad Diagnostic Approach
Authors: Tomcho Thomas J. , Wolfe Wendy L. , Foels Rob
Published: July 2006

We designed a cooperative learning classroom activity to enhance students' ability to understand psychological disorders and distinguish among anxiety, mood, and psychotic disorders. We employed a group interviewing approach with the instructor (or a graduate student) serving as the pseudo-client. Students interacted with a pseudo-client to arrive at a diagnosis. Evaluations of this activity indicated that students learned about various psychological disorders as well as better understood the process of clinical interviewing and diagnosis.
Lhx5 promotes forebrain development and activates transcription of secreted Wnt antagonists
Authors: Peng Gang , Westerfield Monte
Published: July 2006

In vertebrate embryos, induction and patterning of the forebrain require the local inhibition of caudalizing signals, such as Wnts, emanating from the mesendoderm and caudal brain. Here, we report that Lhx5, expressed in the rostral neuroectoderm, regulates the local inhibition of Wnts. Activation of Lhx5 expands forebrain structures, whereas inhibition of Lhx5 function compromises forebrain development in zebrafish embryos. Lhx5 can rescue forebrain deficiencies caused by excess Wnt activity, and inhibition of Lhx5 function results in ectopic activation of Wnt signaling. Lhx5 regulates the expression of two secreted Frizzled-related Wnt antagonists, Sfrp1a and Sfrp5. These Sfrps can reduce the ectopic activation of Wnt signaling and rescue the forebrain deficiencies caused by inhibition of Lhx5 function. Our results demonstrate that Lhx5 is a required factor that promotes forebrain development and inhibits Wnt signaling by activating the transcription of secreted Wnt antagonists.
Differential expression of the adhesion molecule Echinoid drives epithelial morphogenesis inDrosophila
Authors: Laplante Caroline , Nilson Laura A.
Published: July 2006

Epithelial morphogenesis requires cell movements and cell shape changes coordinated by modulation of the actin cytoskeleton. We identify a role for Echinoid (Ed), an immunoglobulin domain-containing cell-adhesion molecule, in the generation of a contractile actomyosin cable required for epithelial morphogenesis in both the Drosophila ovarian follicular epithelium and embryo. Analysis of ed mutant follicle cell clones indicates that the juxtaposition of wild-type and ed mutant cells is sufficient to trigger actomyosin cable formation. Moreover, in wild-type ovaries and embryos, specific epithelial domains lack detectable Ed, thus creating endogenous interfaces between cells with and without Ed; these interfaces display the same contractile characteristics as the ectopic Ed expression borders generated by ed mutant clones. In the ovary, such an interface lies between the two cell types of the dorsal appendage primordia. In the embryo, Ed is absent from the amnioserosa during dorsal closure,generating an Ed expression border with the lateral epidermis that coincides with the actomyosin cable present at this interface. In both cases, ed mutant epithelia exhibit loss of this contractile structure and subsequent defects in morphogenesis. We propose that local modulation of the cytoskeleton at Ed expression borders may represent a general mechanism for promoting epithelial morphogenesis.
Microgravity-induced modifications of the vestibuloocular reflex inXenopus laevistadpoles are related to development and the occurrence of tail lordosis
Authors: Horn Eberhard R.
Published: July 2006

During space flights, tadpoles of the clawed toad Xenopus laevisoccasionally develop upward bended tails (tail lordosis). The tail lordosis disappears after re-entry to 1g within a couple of days. The mechanisms responsible for the induction of the tail lordosis are unknown;physical conditions such as weight de-loading or physiological factors such as decreased vestibular activity in microgravity might contribute. Microgravity(μg) also exerts significant effects on the roll-induced vestibuloocular reflex (rVOR). The rVOR was used to clarify whether tail lordosis is caused by physiological factors, by correlating the occurrence ofμ g-induced tail lordosis with the extent of μg-induced rVOR modifications.

Post-flight recordings from three space flights (D-2 Spacelab mission,STS-55 in 1993; Shuttle-to-Mir mission SMM-06, STS-84 in 1997; French Soyuz taxi flight Andromède to ISS in 2001) were analyzed in these experiments. At onset of microgravity, tadpoles were at stages 25-28, 33-36 or 45. Parameters tested were rVOR gain (ratio between the angular eye movement and the lateral 30° roll) and rVOR amplitude (maximal angular postural change of the eyes during a 360° lateral roll).

A ratio of 22-84% of tadpoles developed lordotic tails, depending on the space flight. The overall observation was that the rVOR of tadpoles with normal tails was either not affected by microgravity, or it was enhanced. In contrast, the rVOR of lordotic animals always revealed a depression. In particular, during post-flight days 1-11, tadpoles with lordotic tails from all three groups (25-28, 33-36 and 45) showed a lower rVOR gain and amplitude than the 1g-controls. The rVOR gain and amplitude of tadpoles from the groups 25-28 and 33-36 that developed normal tails was not affected by microgravity while the rVOR of μg-tadpoles from the stage-45 group with normal tails revealed a significant rVOR augmentation. In conclusion: (1)the vestibular system of tadpoles with lordotic tails is developmentally retarded by microgravity; (2) after a critical status of vestibular maturation obtained during the appearance of first swimming, microgravity activates an adaptation mechanism that causes a sensitization of the vestibular system.
The influence of collagen fiber orientation and other histocompositional characteristics on the mechanical properties of equine cortical bone
Authors: Skedros John G. , Dayton Michael R. , Sybrowsky Christian L. , Bloebaum Roy D. , Bachus Kent N.
Published: July 2006

This study examined relative influences of predominant collagen fiber orientation (CFO), mineralization (% ash), and other microstructural characteristics on the mechanical properties of equine cortical bone. Using strain-mode-specific (S-M-S) testing (compression testing of bone habitually loaded in compression; tension testing of bone habitually loaded in tension),the relative mechanical importance of CFO and other material characteristics were examined in equine third metacarpals (MC3s). This model was chosen since it had a consistent non-uniform strain distribution estimated by finite element analysis (FEA) near mid-diaphysis of a thoroughbred horse, net tension in the dorsal/lateral cortices and net compression in the palmar/medial cortices. Bone specimens from regions habitually loaded in tension or compression were: (1) tested to failure in both axial compression and tension in order to contrast S-M-S vs non-S-M-S behavior, and (2) analyzed for CFO, % ash, porosity, fractional area of secondary osteonal bone, osteon cross-sectional area, and population densities of secondary osteons and osteocyte lacunae. Multivariate multiple regression analyses revealed that in S-M-S compression testing, CFO most strongly influenced total energy(pre-yield elastic energy plus post-yield plastic energy); in S-M-S tension testing CFO most strongly influenced post-yield energy and total energy. CFO was less important in explaining S-M-S elastic modulus, and yield and ultimate stress. Therefore, in S-M-S loading CFO appears to be important in influencing energy absorption, whereas the other characteristics have a more dominant influence in elastic modulus, pre-yield behavior and strength. These data generally support the hypothesis that differentially affecting S-M-S energy absorption may be an important consequence of regional histocompositional heterogeneity in the equine MC3. Data inconsistent with the hypothesis, including the lack of highly longitudinal collagen in the dorsal-lateral `tension' region, paradoxical histologic organization in some locations, and lack of significantly improved S-M-S properties in some locations, might reflect the absence of a similar habitual strain distribution in all bones. An alternative strain distribution based on in vivostrain measurements, without FEA, on non-Thoroughbreds showing net compression along the dorsal-palmar axis might be more characteristic of the habitual loading of some of the bones that we examined. In turn, some inconsistencies might also reflect the complex torsion/bending loading regime that the MC3 sustains when the animal undergoes a variety of gaits and activities, which may be representative of only a portion of our animals, again reflecting the possibility that not all of the bones examined had similar habitual loading histories.
Color discrimination at the spatial resolution limit in a swallowtail butterfly, Papilio xuthus
Authors: Takeuchi Yuichi , Arikawa Kentaro , Kinoshita Michiyo
Published: July 2006

Spatial resolution of insect compound eyes is much coarser than that of humans: a single pixel of the human visual system covers about 0.008°whereas that of diurnal insects is typically about 1.0°. Anatomically, the pixels correspond to single cone outer segments in humans and to single rhabdoms in insects. Although an outer segment and a rhabdom are equivalent organelles containing visual pigment molecules, they are strikingly different in spectral terms. The cone outer segment is the photoreceptor cell part that expresses a single type of visual pigment, and is therefore monochromatic. On the other hand, a rhabdom is composed of several photoreceptor cells with different spectral sensitivities and is therefore polychromatic. The polychromatic organization of the rhabdom suggests that insects can resolve wavelength information in a single pixel, which is an ability that humans do not have. We first trained the Japanese yellow swallowtail butterfly Papilio xuthus to feed on sucrose solution at a paper disk of certain color. We then let the trained butterflies discriminate disks of the training color and grey disks each presented in a Y-maze apparatus. Papiliocorrectly selected the colored disk when the visual angle was greater than 1.18° for blue, 1.53° for green or 0.96° for red: they appeared to see colors in single pixels to some extent. This ability may compensate their rather low spatial resolution.
Cloning and functional expression of voltage-gated ion channel subunits from cnidocytes of the Portuguese Man O'War Physalia physalis
Authors: Bouchard C. , Price R. B. , Moneypenny C. G. , Thompson L. F. , Zillhardt M. , Stalheim L. , Anderson P. A. V.
Published: July 2006

Cnidocytes were dissociated from the tentacles of the Portuguese Man O'War Physalia physalis using heat treatment, and purified using density centrifugation. Visual observation confirmed that these cnidocytes contained a nucleus, a cnidocyst and an apical stereocilium, confirming that the cells were intact. A cnidocyte-specific amplified cDNA library was then prepared using RNA isolated from the cnidocytes, and screened for voltage-gated ion channel subunits using conventional molecular cloning techniques. A variety of channel proteins were identified and full-length sequence obtained for two of them, a Ca2+ channel β subunit(PpCaVβ) and a Shaker-like K+channel (PpKV1). The location of the transcripts was confirmed by RT-PCR of total RNA isolated from individually selected and rinsed cnidocytes. The functional properties of these two channel proteins were characterized electrophysiologically using heterologous expression. PpCaVβ modulates currents carried by both cnidarian and mammalian α1 subunits although the specifics of the modulation differ. PpKV1 produces fast transient outward currents that have properties typical of other Shaker channels. The possible role of these channel proteins in the behavior of cnidocytes is discussed.
Effects of hypo- and hyperoxia on transcription levels of five stress genes and the glutathione system in liver of Atlantic cod Gadus morhua
Authors: Olsvik P. A. , Kristensen T. , Waagbø R. , Tollefsen K.-E. , Rosseland B. O. , Toften H.
Published: July 2006

The transcript levels of three genes coding for antioxidants, Cu/Zn superoxide dismutase (SOD), catalase and phospholipid hydroperoxide glutathione peroxidase (GSH-Px), and those of two stress proteins,metallothionein (MT) and CYP1A, were examined with real-time quantitative (q)RT-PCR in hepatic tissue of Atlantic cod exposed to 46% (hypoxia), 76%(normoxia) and 145% (hyperoxia) O2 saturation (tank outlet). To evaluate the oxidative stress state, the levels of total glutathione (tGSH),reduced glutathione (GSH) and oxidized glutathione (GSSG) and subsequently the oxidative stress index (OSI), were determined in the same tissue samples. The transcript level of GSH-Px was significantly upregulated in fish exposed to hyperoxia, and significantly downregulated in fish exposed to hypoxia,compared to the normoxia group. Significant downregulation was also found for SOD and CYP1A transcriptional levels in fish exposed to hypoxia. The transcript levels of catalase and MT did not change in liver of cod exposed to suboptimal oxygen levels. No significant differences were seen between the groups for tGSH, GSH, GSSG or OSI. Prolonged exposure to unfavourable oxygen saturation levels did not alter the OSI, indicating that the antioxidant glutathione system is maintained at an unchanged level in liver of the examined cod.
Feeding and osmoregulation: dual function of the marine teleost intestine
Authors: Taylor Josi R. , Grosell Martin
Published: July 2006

Experiments on Gulf toadfish Opsanus beta demonstrate how feeding impacts osmoregulation in the marine teleost intestine. A high Ca2+diet of pilchards Sardina pilchardus ([Ca2+]=404.2 mmol kg-1) was compared to a low Ca2+ diet of common squid Loligo forbesi ([Ca2+]=1.3 mmol kg-1), as high[Ca2+] has been shown to stimulate intestinal anion exchange. Gastrointestinal fluids and blood plasma were collected over a time course from pre-feeding to 216 h post feeding. Following food intake, monovalent ions were largely absorbed across the intestinal epithelium, leaving a fluid rich in divalent ions, which have a lower osmotic coefficient and effectively reduce osmotic pressure in the lumen to allow for enhanced fluid absorption. Concentrations of Cl- and HCO -3 in fluid along the gastrointestinal tract of fish fed both diets, particularly 1 and 2 days post-feeding, demonstrate that apical Cl-/HCO -3 exchange plays a vital role in postprandial Cl- and water absorption. Postprandial acid-base balance disturbance as indicated by plasma alkalinization was limited or absent,indicating compensation for gastric acid secretion in this teleost fish. Plasma osmolality peaked 12 h post-feeding in toadfish fed squid, but was not accompanied by a significant increase in inorganic ion concentrations. Transient fluid secretion by the gastrointestinal tract was evident from reduced luminal Mg2+ and SO 2-4concentrations for 24-48 h post feeding. Discrepancy between the sum of inorganic osmolytes and measured osmotic pressure was attributed to organic osmolytes, which occurred at high concentrations in the stomach and anterior intestine for up to 24 h post feeding.
Intestinal anion exchange in marine fish osmoregulation
Authors: Grosell Martin
Published: July 2006

Despite early reports, dating back three quarters of a century, of high total CO2 concentrations in the intestinal fluids of marine teleost fishes, only the past decade has provided some insight into the functional significance of this phenomenon. It is now being recognized that intestinal anion exchange is responsible for high luminal HCO3- and CO32- concentrations while at the same time contributing substantially to intestinal Cl- and thereby water absorption, which is vital for marine fish osmoregulation. In species examined to date, the majority of HCO3- secreted by the apical anion exchange process is derived from hydration of metabolic CO2 with the resulting H+ being extruded via a Na+:H+ exchange mechanism in the basolateral membrane. The basolateral H+ extrusion is critical for the apical anion exchange and relies on the Na+ gradient established by the Na+-K+-ATPase. This enzyme thereby ultimately fuels the secondary active transport of HCO3- and Cl-by the apical anion exchanger. High cellular HCO3-concentrations (>10 mmol l-1) are required for the anion exchange process and could be the result of both a high metabolic activity of the intestinal epithelium and a close association of the anion exchange protein and the enzyme carbonic anhydrase. The anion exchange activity in vivo is likely most pronounced in the anterior segment and results in net intestinal acid absorption. In contrast to other water absorbing vertebrate epithelia, the marine teleost intestine absorbs what appears to be a hypertonic fluid to displace diffusive fluid loss to the marine environment.
Functional imaging of dolphin brain metabolism and blood flow
Authors: Ridgway Sam , Houser Dorian , Finneran James , Carder Don , Keogh Mandy , Van Bonn William , Smith Cynthia , Scadeng Miriam , Dubowitz David , Mattrey Robert , Hoh Carl
Published: July 2006

This report documents the first use of magnetic resonance images (MRIs) of living dolphins to register functional brain scans, allowing for the exploration of potential mechanisms of unihemispheric sleep. Diazepam has been shown to induce unihemispheric slow waves (USW), therefore we used functional imaging of dolphins with and without diazepam to observe hemispheric differences in brain metabolism and blood flow. MRIs were used to register functional brain scans with single photon emission computed tomography (SPECT)and positron emission tomography (PET) in trained dolphins. Scans using SPECT revealed unihemispheric blood flow reduction following diazepam doses greater than 0.55 mg kg-1 for these 180-200 kg animals. Scans using PET revealed hemispheric differences in brain glucose consumption when scans with and without diazepam were compared. The findings suggest that unihemispheric reduction in blood flow and glucose metabolism in the hemisphere showing USW are important features of unihemispheric sleep.

Functional scans may also help to elucidate the degree of hemispheric laterality of sensory and motor systems as well as in neurotransmitter or molecular mechanisms of unihemispheric sleep in delphinoid cetaceans. The findings also demonstrate the potential value of functional scans to explore other aspects of dolphin brain physiology as well as pathology.
The Occurrence of a D–D Mechanism in the Ethanol Solution of Eosine
Authors: Nemoto Masae , Usui Yoshiharu , Koizumi Masao
Published: July 2006

The occurrence of a D–D mechanism in which the photochemical reaction is initiated by the interaction of the triplet dye and the ground-state dye molecules, has been established for the ethanol solution of eosine. Chief evidence for it has been afforded by: 1) the predominance of the second-order reaction at high dye concentrations, 2) the dependence of the quantum yield of the photoreduction upon the dye concentration, and 3) the effect of the dye concentration on the photochemical oxygen absorption and on the oxydative photobleaching of dye. Assuming no simple deactivation between the triplet dye and allylthiourea, the quantum yield for the formation of the triplet dye has been evaluated as 0.056. Then the rate constants for the following elementary reactions, (Remark: Graphics omitted.) and DT+ATU→intermediate are, respectively, 1×108  m−1sec−1 and 1–2×105  m−1sec−1. It seems that the reaction between oxygen and the triplet dye is chiefly an eventual deactivation of the latter, with no appreciable decomposition of the dye or of ethanol.
The Reactions between a Rhenium Filament and Oxygen at High Temperatures and Low Pressures
Authors: Hamamura Takuya , Tomita Genzo
Published: July 2006

The rate of the reaction of oxygen with a rhenium filament under a filament temperature of (1500–2100)°K and an oxygen pressure of (2×10−4–4×10−6)mmHg have been measured with a flow method. The reaction rate increases with an increase in the temperature, reaches zu maximum at about 1800°K, and then decreases with a further increase in the temperature. The reaction rate is proportional to the 0.9th power of the oxygen pressure below 1700°K, whereas it is proportional to the 1.8th power above 1900°K. The apparent compositions of the rhenium oxides produced in the reaction have been determined from the weight change of the filament, and the oxides in the formulas of Re2O7 and ReO3 have been found. For purposes of comparison, the reaction rates of oxygen with a tungsten filament have also been measured by the same method.
Semi-Empirical SCF Molecular Orbital Treatment for Valence Electron Systems. II. Small Ionic Intermediates
Authors: Yonezawa Teijiro , Kato Hiroshi , Konishi Hideyuki
Published: July 2006

Familiar small ionic intermediates are treated by the semi-empirical SCF method previously proposed for all valence electron systems by the present authors. The calculated orbital energies are compared with the results of other full SCF calculations and the experiments. The agreements between them are satisfactory. Utilizing the calculated orbital charge distributions and the atomic dipole values, the reactivities and the most reactive centers of these ions are discussed. The calculated results on the proton affinities and the excitation energies of various compounds are also presented.
Studies of the Photochemistry of Aromatic Diazo Compounds. III. The Electronic Structures of Some m-Substituted Benzenediazonium Cations
Authors: Sukigara Mitsunori , Kikuchi Shin-ichi
Published: July 2006

The electronic structures and electronic absorption spectra of m-fluoro-, m-chloro-, m-bromo-, and m-methoxybenzenediazonium cations were studied by making molecular orbital calculations, and by measuring the near-ultraviolet absorption spectra. From the calculations it is understood that when an electron-donating group is introduced at the m-position of the benzenediazonium cation, a mixing of the lowest locally-excited 1B1 state within the benzenediazonium cation and the intramolecular charge-transfer state arising from the electron transfer from the electron-donating group at the m-position to the lowest unoccupied molecular orbital of the benzenediazonium framework comes to show a large contribution of the substituted cation in the lowest excited state while at the same time the energy of the corresponding state is lowered. The ground and the excited 1A1 states of the nonsubstituted cation are not so greatly affected by the m-substitution as is the 1B1 state. The degree of the mixing of the 1A1 and 1B1 state of the benzenediazonium cation by the m-substitution is not so impotant in the ground and lower excited states of the m-substituted benzenediazonium cation.
Effect of Nitrous Oxide on the Radiolysis of Liquid Methanol with the Recoils from the 10B(n, α)7Li Reaction
Authors: Imamura Masashi , Seki Hiroshi
Published: July 2006

Liquid methanol containing trimethyl borate and nitrous oxide was irradiated with thermal neutrons from a nuclear reactor. In contrast to the marked effect on the γ-radiolysis yields, nitrous oxide had a little effect on the recoil radiolysis yields from methanol, and nitrogen yield was as low as 0.2 in G unit. These results indicate that the yield of the solvated electron in the recoil radiolysis of methanol is about one tenth of that in the γ-radiolysis.
The Reaction between Mercury(II) and Organic Compounds. II. The Composition of a Mercury(II)-l-Histidine Complex in an Ethanol-Water Solution
Authors: Kai Fumiaki
Published: July 2006

The composition of the complex formed with l-histidine and mercury(II) in a solution has been investigated spectroscopically. The complex formation in an aqueous solution was not observed, but in an alcoholic solution (1 : 1), there appeared about 274 mμ an absorption maximum which can be attributed to the complex formation. By the spectroscopic measurements of this alcoholic solution containing two components in various proportions, it was shown that only one kind of complex with a 1 : 1 composition was formed in a 50% ethanol-water solution at pH 3.25–3.75 and at 20°C. Accordingly, the composition of the complex may be considered to be as follows:

(Remark: Graphics omitted.)
Crystalline Complex of Allyl Alcohol with Copper(I) Chloride
Authors: Ogura Tetsuya , Furuno Nobuo , Kawaguchi Shinichi
Published: July 2006

A colorless crystalline complex of allyl alcohol with copper(I) chloride, (CH2=CHCH2OH)-CuCl, was synthesized at room temperature in a vacuum system. A similar complex with calcium chloride was also prepared for the sake of comparison. The equilibrium vapor pressure of the copper (I) chloride complex was determined at vairous temperatures, and ΔH=−12.0 kcal/mol was obtained as the heat of formation from solid copper (I) chloride and gaseous allyl alcohol. The C=C stretching frequency of allyl alcohol is shifted by 95 cm−1 to the lower frequency side by ligation to copper (I). The C–O stretching band shows a very minor shift of 15 cm−1. This value is almost the same as in the calcium chloride complex. Thus, in the copper (I) chloride complex, allyl alcohol coordinates to the metal mainly through the double bond, but the OH group also participates in the coordination. By measuring the decrease in vapor pressure, copper(I) chloride was found to exist as a dimer in allyl alcohol at 23–43°C, but as a monomer at 97°C.
Mechanistic Aspects of the Formation and Decomposition of the Cyclic Anhydride of β-Sulfopropionic Acid. A Study of Radical Rearrangement Using a Labeled Compound
Authors: Nagai Toshikazu , Nishitomi Katsuhiko , Tokura Niichiro
Published: July 2006

The photochemical sulfonation of propionic-α, α-d2-acid-d1 (83% isotopic purity at the α-position) with sulfuryl chloride to form the cyclic anhydride of the deuterated β-sulfopropionic acid was carried out. The isotopic purity of the resulting anhydride decreased to 55±2% at the α-position. This result indicates that an α-hydrogen is abstracted in a ratio of 67.5±5%, followed by the rearrangement of a β-hydrogen prior to the sulfonation at the β-carbon atom. The mechanism is somewhat different from that proposed by Kharasch et al. [M. S. Kharasch, T. H. Chao and H. C. Brown, J. Am. Chem. Soc., 62, 2393 (1940)] for the photosulfonation of propionic acid. The present paper will also study the thermal decomposition of the cyclic anhydride to produce acrylic acid; its mechanistic aspects will be considered.
Considerations on the Nuclear Magnetic Resonance Spectra of Some Anomeric Tetra-O-acetyl-d-glucopyranosides
Authors: Tsuzuki Yojiro , Tanaka Katsumi
Published: July 2006

We have measured the nuclear magnetic resonance spectra (NMR) of some anomers of aryl 2,3,4,6-tetra-O-acetyl-d-glucopyranosides and found that the signal of the anomeric proton in the α-anomers could be separated from the signals due to the other protons, and that the chemical shift in fact distinctly appeared in a lower mangetic field (δ=5.95 ppm, J=3.0 to 3.5 cps) than those in alkyl 2,3,4,6-tetra-O-acetyl-d-glucopyranosides. Lower field shifts have also been observed in β-anomers, but it was impossible to determine the chemical shift exactly possibly because of the overlapping with the signals due to the other protons attached to the pyranose ring.
An Investigation of the Mechanism of the Henkel Reaction by Deuterium and Carbon-14 Isotope Techniques
Authors: Furuyama Shozo
Published: July 2006

The thermal rearrangements and the disproportionation of potassium benzenecarboxylates have been investigated at 350–460°C using potassium deuterophthalate, deuterobenzoate, benzoate-1-14C and benzoate-7-14C. The following results were obtained: (1) Hydrogen atoms of potassium phthalate and benzoate transfer intermolecularly during the conversion. The hydrogen atoms seem to exchange many times. (2) The intermolecular transfer of hydrogen atoms also takes place between different benzenecarboxylates. (3) The hydrogen atoms transfer intermolecularly many times, irrespective of either the reaction temperature, the kinds of catalysts, and the kinds of potassium carboxylates. (4) The hydrogen exchange takes place only during the conversion. (5) Many of the carboxyl groups of potassium benzoate are replaced by carbon dioxide in the gas phase and by carbon dioxide from potassium carbonate. A possible mechanism is presented.
Studies of the Model Compounds of Cyclopolymers. An NMR Spectroscopic Study of cis and trans Isomers of 2, 5-Dimethoxytetrahydrofuran
Authors: Aito Yuzo , Matsuo Taku , Aso Chuji
Published: July 2006

The configurational isomers of 2, 5-dimethoxytetrahydrofuran were synthesized as model compounds of the cyclopolymer of succinaldehyde. The NMR spectra of the isomers were then studied in carbon tetrachloride and in benzene. From the behavior of the methyl and methylene protons of the isomers in chemical shifts and in the formation of a “loose-complex” with benzene, it was concluded that the isomer with the lower boiling point had a trans configuration and that the isomer with the higher boiling point had a cis configuration. The NMR spectrum of 2, 5-dimethoxy-2, 5-dihydrofuran was similarly investigated in order to compare it with that of 2, 5-dimethoxytetrahydrofuran. The spectrum was rather simple; each signal was assigned to the cis or to the trans configurational isomer.
ESR Studies on the Behavior of Fluorescein Semiquinone
Authors: Okuda Michio , Momose Yoshihiro , Niizuma Shigeya , Koizumi Masao
Published: July 2006

The structure and reactivity of different types of fluorescein semiquinone were studied in an alkaline solution pH 11–14, by the ESR method. The hyperfine structures with more than fifty lines are semiquantitatively interpreted by the McLachlan method. The three lines with the largest splitting constant, 3.44G, were attributed to the protons at the next neighboring carbon atoms (on the outside benzene ring) from the central carbon atom. The decay of semiquinone obeys the second order, but the rate constant depends largely on the pH. This difference was attributed to the difference in the reactivities of semiquinone monoanion, dianion, and trianion. The activation energy, however, was found to be about 10–12 kcal/mol, regardless of the pH. In order to interpret the above results a mechanism was proposed in which the essential process is the recombination of two radical anions at the position of the central carbon atoms. Evidence for this mechanism was afforded by the calculation of the delocalization energy for the above process, which has proved to be almost constant for different species of semiquinone.
Electronic Structures and Luminescence Properties of Phenazine Derivatives
Authors: Mataga Noboru , Ezumi Kiyoshi
Published: July 2006

The electronic structures and luminescence properties of phenazine derivatives (1, 5-dichloro-, -dihydroxy-, -dimethoxy-, and -diamino-phenazine) have been studied. The observed absorption spectra and the solvent effects on the spectra have been interpreted satisfactorily on the basis of the quantum mechanical calculation of the pi-electronic states of these molecules. From the results of this calculation, as well as from the fluorescence properties of these molecules, it has been established that the lowest excited singlet state is 1(π–π*) (the 1La state more or less modified by the substitution) in all of these molecules, in contrast to the case of the phenazine molecule, where 1(n–π*) is the lowest singlet excited state, leading to the non-fluorescent property of this molecule. The effects of hydrogen bonding and acid-base interactions on the fluorescence properties of the phenazine derivatives have been examined. The inter and intra-molecular hydrogen bonding as well as the protonation interactions at the ring nitrogen cause, in general, a large decrease in the fluorescence yields of these molecules, in contrast to the case of acridine and acridine derivatives, where the interactions with aliphatic alcohols and acids affect the fluorescence yield only slightly or even increase it. The mechanism of this fluorescence quenching has been discussed on the basis of a radiationless vibronic coupling between the relevant electronic states.
Catalytic Decomposition of Methanol over Nickel Wire
Authors: Yasumori Iwao , Nakamura Tetsuro , Miyazaki Eizo
Published: July 2006

The kinetic studies of the decomposition of methanol have been undertaken under pressures of up to 20 mmHg and at temperatures between 300 and 430°C. The initial rate (r0) of decomposition which turns methanol into carbon monoxide and hydrogen was found to be expressed by the equation, r0=aPm⁄(1+b\sqrtPm)2 where Pm is the initial pressure of methanol and where a and b are constants. The addition of carbon monoxide to the reactant was found to depress the rate of reaction, while a slight promotion was observed upon the addition of hydrogen to the system. On the other hand, when the kinetics of the decomposition of formaldehyde, which was regarded as the intermediate product in the methanol decomposition, was studied, it was found that formaldehyde decomposed to cabon monoxide and hydrogen, and that the rate was much larger than that of methanol decomposition. On the basis of these results and the exchange reaction of methanol with deuterium, the processes of methanol decomposition were discussed in detail and a possible mechanism of reaction was proposed in which the surface reaction between the adsorbed methoxy radical and the hydrogen atom, both produced by the dissociative adsorption of methanol, is the rate-determining step of the reaction.
Nickel(II), Cobalt(II) and Copper(II) Complexes of 2,2′-Diaminobiphenyl
Authors: Onaka Satoru , Iwamoto Toschitake , Sasaki Yukiyoshi , Fujiwara Shizuo
Published: July 2006

Nickel(II), cobalt(II) and copper(II) complexes of 2, 2′-diaminobiphenyl were prepared in an autoclave under a high pressure and a high temperature as the acetates: Ni(C12H12N2)2-(CH3CO2)2, Co(C12H12N2)2(CH3CO2)2 and Cu(C12H12N2) (CH3CO2)2. They are sparingly soluble in water and in non-polar solvents, but are soluble in some polar solvents. The presence of a monomer complex was verified by a molecular weight determination in a methyl ethyl ketone solution for both the cobalt and copper complexes. Analytical, magnetic susceptibility, powder X-ray diffraction, diffuse reflection spectral, infrared spectral, and ESR spectral data are given, and the geometric isomerism of the complexes is discussed.
Studies on the Chemical Constitution of Agar-agar. XXIV. Isolation of a New Disaccharide as a Reversion Product from Acidic Hydrolysate
Authors: Araki Choji , Arai Kiyoshi
Published: July 2006

The careful separation of the products of the complete hydrolysis of commercial agar on charcoal-Gelite columns has led to the isolation of a new reducing disaccharide, named “isoagarobiose,” in a yield of 1.5% of the agar sample. Its crystalline phenylosazone and crystalline hexa-acetate have also been prepared. On methanolysis the disaccharide gave methyl d-galactoside and 3, 6-anhydro-l-galactose dimethyl acetal. Complete methylation, followed by methanolysis, yielded 2, 4, 5-tri-O-methyl-3, 6-anhydro-l-galactose dimethyl acetal and methyl 2, 3-di-O-methyl d-galactoside. It follows from these results that the disaccharide has an unusual structure, in which the C1 of the 3, 6-anhydro-aldehydo-l-galactose residue is linked, through cyclic acetal linkages, with the C4 and C6 of the d-galactose residue. Evidence is provided that the disaccharide is not involved in the polysaccharide molecule, but has been formed by acid reversion from d-galactose and 3, 6-anhydro-l-galactose during the hydrolysis of the polysaccharide. The formation of the cyclic acetal linkages is accounted for in terms of the peculiar property of the anhydrosugar, which exists in an aldehyde form, with an open-chain structure.
The Dehydrogenation of ortho-Tropylphenols and the Synthesis of Furano-p-benzoquinonetropides
Authors: Nozoe Tetsuo , Takahashi Kazuko
Published: July 2006

The intermolecular disproportionation reaction between 2-methoxy-10aH-cyclohepta-[b]benzofuran (4) and 2-acetoxy-3-methoxyphenyltropylium ion (2) occurred upon the treatment of 2 with 2 n hydrochloric acid, thus affording 3′-methoxy-2′, 2-epoxyphenyltropylium ion (5) and 3-(2-acetoxy-3-methoxyphenyl)tropilidene (6). 3H-Cyclohepta[b]benzofuran-3-one (furano-p-benzoquinonetropide) (25), its ethyl (30), chloro (35), acetyl (40) and hydroxy (48) derivatives were synthesized by the application of this disproportionation reaction to the dehydrogenation products of 4-tropyl, 6-ethyl-4-tropyl, 6-chloro-4-tropyl, 6-acetyl-4-tropyl resorcinol and 4-tropylphroglucinol triacetate respectively. The electronic spectra of these furano-p-benzoquinonetropides (25), (30), (35), and (40), in water showed their long wavelength absorption maxima at mμ (logε) values of 540 (3.74), 568 (3.57), 512 (3.83) and 512 (3.51) respectively. However the spectra of these compounds in chloroform showed the peaks at mμ (logε) values of 635 (3.03), 685 (3.61), 665 (3.56) and 600 (3.50) respectively, the peaks had shifted to wave-lengths longer by 100–150 mμ than those in water. This solvent effect, the reverse of the case of p-benzoquinonetropides, may be interpreted in terms of an increased contribution by the polar structure to the ground state as a result of the formation of the furan ring.
Correlation of the Physical Properties of Organophosphorus Compounds. I. Density, Boiling Point, and the Heat of Evaporation of Phosphines
Authors: Arshad M , Beg A
Published: July 2006

The boiling point and density of the phosphines have been correlated by using the quantity Mρ2. The use of such data permits the classification of these compounds into associated and normal liquids. These conclusions are also supported by the study of the heat of evaporation of the phosphines.
Antituberculous Compounds. XXV. Some Derivatives of Pyrido[2, 3-d]pyridazine
Authors: Kakimoto Shichiro , Tonooka Shuichi
Published: July 2006

Attempts to prepare 5, 6-dihydropyrido[2, 3-d]pyridazin-8(7H)-one by the hydrogenation of pyrido[2, 3-d]pyridazin-8(7H)-cne were not successful, but it was found that the hydrogen-ated compound was 1, 2, 3, 4-tetrahydropyrido[2, 3-d]pyridazm-8(7H)-one. The same reaction occurred in the case of pyrido[2, 3-d]pyridazin-5(6H)-one and some other derivatives.
The Crystal Structure of 2-Anilino-3-bromo-tetrahydro-exo-dicyclopentadiene
Authors: Tanaka Nobuo , Ashida Tamaichi , Sasada Yoshio , Kakudo Masao , Kasai Nobutami
Published: July 2006

2-Anilmo-3-bromo-tetrahydro-exo-dicyclopentadiene, C16H20NBr, crystallizes in the monoclinic space group P21⁄c, with four molecules in a unit cell of dimensions a=9.15, b=17.36, c=9.56 Å, β=108.45°. The structure was solved by superimposing the minimum function upon the first Fourier map based on the Br atom only. The atomic parameters were refined by the block-diagonal least-squares method. Most of bond-angles of carbon atoms forming a tricyclic system in the molecule are somewhat smaller than the ordinary tetrahedral angle, particularly on the bridged carbon atom. The Br atom is bonded to the endo side of the ring and the N atom to exo.
Electrochemical Syntheses. IV. The Homolytic Methoxylation and Ethoxylation of Olefins by the Anodic Oxidation of Methanol and Ethanol
Authors: Inoue Tadao , Koyama Kikuhiko , Matsuoka Toru , Tsutsumi Shigeru
Published: July 2006

The electrochemical oxidation of methanol and ethanol in the presence of trans-stilbene, cis-stilbene, norbornene, and styrene has been studied. The major gaseous and nongaseous products have been identified and determined, and the corresponding dimethoxylated derivatives and diethoxylated derivatives have been obtained in fairly high yields. The main path by which these products may have arisen has been discussed, and the stereochemistry of the addition of methoxy radicals to stilbene has been discussed. Particular attention has been given to the possibility that the main product arises from the anodic oxidation of an intermediate radical to a carbonium ion.
The Chemiluminescent Polymer
Authors: Omote Yoshimori , Ohmori Seiya , Sugiyama Noboru
Published: July 2006

The synthesis and the chemiluminescence of poly(acrylylluminol-ir-acrylic acid) (II) are described. It was found that the reaction product of the chemiluminescence of II is roughly identical with the corresponding poly(acrylylaminophthalic acid-ir-acrylic acid). Also, it was found that II shows a stronger chemiluminescence than the monomeric N-propionylluminol (III) based on the same N-acylluminol unit in DMF-water (3:1 in vol), while II shows a weaker chemilluminescence in water.
The Reaction of Cyclooctatetraene Oxide with Grignard Reagents
Authors: Matsuda Tsutomu , Sugishita Masahiko
Published: July 2006

The reaction of cyclooctatetraene oxide with ethylmagnesium bromide, phenylmagnesium bromide and t-butylmagnesium bromide was found to yield 2, 4, 6-cycloheptatrienyl-1-ethyl-, phenyl- and t-butylcarbinol respectively. The treatment of cyclooctatetraene oxide with a catalytic amount of magnesium bromide in ether afforded phenyl acetaldehyde in a 76% yield. The dehydration of the carbinols with a catalytic amount of p-toluenesulfonic acid resulted in their further rearrangement to trans-β-substituted styrenes.
Preparation of Block Copolymer of ε-Caprolactone with Living Polystyrene
Authors: Nobutoki Koji , Sumitomo Hiroshi
Published: July 2006

ε-Caprolactone was polymerized by using living polystyrene prepared by means of an anionic polymerization technique. A gross polymer was elution-fractionated into four fractions which were methanol-soluble low-molecular-weight polyester, high-molecular-weight polyester, a small amount of polystyrene and polystyrene-polyester block copolymer. Both yields and molecular weights of block copolymers were observed to be higher in benzene than in tetrahydrofuran. Formation of block copolymers was concluded from the results of an elementary- and infrared analyses and turbidometry. Polymerization mechanism of ε-caprolactone is discussed.