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The electronic and infrared spectra of jet-cooled 4-aminobenzonitrile–(H2O)1 (4ABN–(H2O)1) hydrogen-bonded complex have been measured by the resonance-enhanced multiphoton ionization (REMPI) and infrared-dip (IR-dip) spectroscopy. Both the amino and cyano groups form intermolecular hydrogen bond with water, providing two stable isomers. It has been found that the substitution of the CN group at the para-position of aniline changes the electronic nature of the amino group in the S0 state from a proton acceptor to a proton donor.

Structures of (aniline–benzene) + and (aniline) 2 + are re-investigated by electronic spectroscopy in the near-infrared region and vibrational spectroscopy in the NH stretching region. The spectra of (aniline–benzene) + indicate a structure including a hydrogen bond between an NH bond of the ionic aniline and the π-electrons of the neutral benzene. Two isomers are suggested for (aniline) 2 + in which an NH bond of the ionic aniline forms different types of hydrogen bond with the neutral aniline: one with the π-electrons of the aromatic ring and the other with the lone pair of the nitrogen atom.

The observation of a dual fluorescence in the emission spectra of jet-cooled benzonitrile and p-tolunitrile has been reported by Mordzinski et al. [J. Phys. Chem. A 101 (1997) 8221], and a broad, red-shifted component has been assigned as a transition from a rehybridized intramolecular charge-transfer (RICT) state. However, the dispersed fluorescence spectra measured at much higher resolution clearly show that the broad feature consists of many sharp features, indicating that emission from the RICT state is absent.

The coupling of two large amplitude motions, the internal rotation of the methyl group and the intramolecular proton transfer, has been investigated for jet-cooled 5-methyltropolone, 5-methyltropolone–OD, and the 5-methyltropolone–(H2O)1 1:1 hydrogen-bonded complex by measuring the fluorescence excitation, dispersed fluorescence, and hole-burning spectra in the S1–S0 region. The vibronic bands in the excitation spectrum of 5-methyltropolone consist of four components originating from the transitions between the sublevels in the S1 and S0 states. The intensity of the bands, the frequencies, and the change in the stable conformation of the methyl group upon photoexcitation have been analyzed for 5-methyltropolone–(H2O)1 by calculating the one-dimensional periodic potential function, which provides the correlation between the internal rotational levels of 5-methyltropolone–(H2O)1 and the sublevels of 5-methyltropolone. It has been shown that the electronic transitions between the sublevels within the same sy...

The S1–S0 electronic spectra of jet-cooled 5-phenyltropolone were measured to elucidate the features of phenyl torsion and its effect on intramolecular proton transfer. Several bands in the fluorescence excitation spectra were assigned to phenyl torsion and other low-frequency modes with the aid of the ab initio calculation. The torsional potential energy function was investigated with the one-dimensional torsional potential function analysis for the S0 state. Presence of significant potential barriers due to the large H-atom steric repulsion between the phenyl ring and the tropolone ring were anticipated at the torsional angle φ=0° in both the S0 and S1 states. It was suggested that the large steric repulsion significantly influenced both phenyl torsion and proton transfer.

The S0–S1 electronic spectra of ortho-hydroxytropolone (o-OHTR) in supersonic jets were measured in order to study its isomerism. Only one isomer has been detected in a supersonic jet. A blue shift of electronic origin due to deuteration of two -OH groups was twice as large as that of one -OH group, suggesting that the configurations of the two -OH groups in o-OHTR are equivalent. This finding is consistent with the results of the ab initio calculations. The origin bands of the complexes with water and acetone were red-shifted from that of the bare molecule. The red-shift was explained in terms of two opposite effects of formation of an intermolecular hydrogen bond on each of two intramolecular hydrogen bonds.

The broad and sharp absorption systems of anthracene in the 362−376 nm region have been confirmed to be due to dimeric species by measuring the resonantly enhanced two-photon ionization mass spectrum. The hole-burning spectrum indicated that two stable isomers exist in the S0 state. The decay time of the excimer emission (300 ns) from the broad system is much longer than that of the emission from the sharp system (15 ± 5 ns), indicating that the electronic nature of the excited state is very different between the two systems. The difference in the excited-state potentials of the two systems has been discussed on the basis of the vibronic structures and the emission lifetimes.

The fluorescence excitation and hole-burning spectra in the S1–S0 region of 5-methyltropolone have been measured in a supersonic free jet. It has been found that the electronic origin of 5-methyltropolone splits into four components corresponding to the transitions between the sublevels of the zero-point levels in the S0 and S1 states originating from coupled motion of the internal rotation of the methyl group and proton transfer. The tunneling rate of the zero-point level in the S1 state is one order smaller than that of tropolone due to this coupling, but the excitation of the internal rotational levels promotes proton tunneling.

Electronic spectra of a homo-molecular dimer cation, (C6H5CN)2+, are measured by photodissociation spectroscopy in the gas phase. Broad features appeared in the 450–650 nm region are characteristic of π3 → πCN transitions of the C6H5CN+ chromophore. No intense band is observed in the 650–1300 nm region, where other aromatic dimer cations usually show charge resonance bands. Two component molecules of (C6H5CN)2+ cannot take a parallel sandwich configuration suitable for the resonance interaction, because of geometrical constraints due to other stronger interactions., This work was supported in part by a Grant-in-Aid for Scientific Research (No. 09740450) from the Ministry of Education, Science, Sports and Culture of Japan., This is a postprint of an article published by Springer Netherlands in Research on Chemical Intermediates, 1998, available online: http://doi.org/10.1163/156856798X00393

Proton tunneling in the S1 state of jet-cooled tropolone−(N2)n (n = 1, 2) and tropolone−(CO)1 van der Waals complexes is investigated by measuring the hole-burning and fluorescence excitation spectra in the S1−S0 region. The hole-burning spectra enabled us to separate three overlapping absorption systems due to transitions between low-wavenumber and high-wavenumber tunneling doublet components of tropolone−(N2)1 and those of tropolone−(N2)2. The 0−0 tunneling doublet splitting of tropolone−(N2)1 has been confirmed to be 9.7 cm-1. It has been suggested that the magnitude of the tunneling splitting depends on the excited intermolecular vibrational level. In addition to the sandwich isomer I for tropolone−(N2)2 observed previously, a second isomer [II] has been identified. A much smaller microscopic red shift (−57.9 cm-1) than the corresponding value (−129.0 cm-1) for isomer I indicates that two N2 molecules are on the same side of the tropolone ring in isomer II. No tunneling splitting has been observed for...

The electronic spectrum of a jet-cooled tropolone–acetone 1:1 complex has been measured to examine the effects of the intermolecular hydrogen bond on the intramolecular hydrogen bond of tropolone. The stable structure, vibrational frequencies and the spectral shift have been discussed by combining the experimental results with ab initio data.

Brain injury induces phenotypic changes in astrocytes, known as reactive astrogliosis, which may influence neuronal survival. Here we show that brain injury induces inositol 1,4,5-trisphosphate (IP 3 )-dependent Ca 2+ signaling in astrocytes, and that the Ca 2+ signaling is required for astrogliosis. We found that type 2 IP 3 receptor knockout (IP 3 R2KO) mice deficient in astrocytic Ca 2+ signaling have impaired reactive astrogliosis and increased injury-associated neuronal death. We identified N-cadherin and pumilio 2 (Pum2) as downstream signaling molecules, and found that brain injury induces up-regulation of N-cadherin around the injured site. This effect is mediated by Ca 2+ -dependent down-regulation of Pum2, which in turn attenuates Pum2-dependent translational repression of N-cadherin. Furthermore, we show that astrocyte-specific knockout of N-cadherin results in impairment of astrogliosis and neuroprotection. Thus, astrocytic Ca 2+ signaling and the downstream function of N-cadherin play indispensable roles in the cellular responses to brain injury. These findings define a previously unreported signaling axis required for reactive astrogliosis and neuroprotection following brain injury.

The S 1 S 0 fluorescence excitation and dispersed fluorescence spectra of jet-cooled tropolone-(H 2 O) n ( n = 1–3) have been measured to investigate the effects of the solvation by water on proton tunneling. Three intermolecular vibrational modes have been observed in the dispersed fluorescence spectrum. Ab initio calculations suggest that two stable conformers exist for tropolone-(H 2 O) 1 . The structure of tropolone-(H 2 O) 1 has been discussed by comparing the observed and calculated vibrational frequencies.

Rearrangement of intermolecular hydrogen bond in a monohydrated tryptamine cation, [TRA(H(2)O)(1)](+), has been investigated in the gas phase by IR spectroscopy and quantum chemical calculations. In the S(0) state of TRA(H(2)O)(1), a water molecule is hydrogen-bonded to the N atom of the amino group of a flexible ethylamine side chain [T. S. Zwier, J. Phys. Chem. A 105, 8827 (2001)]. A remarkable change in the hydrogen-bonding motif of [TRA(H(2)O)](+) occurs upon photoionization. In the D(0) state of [TRA(H(2)O)(1)](+), the water molecule is hydrogen-bonded to the NH group of the indole ring of TRA(+), indicating that the water molecule transfers from the amino group to NH group. Quantum chemical calculations are performed to investigate the pathway of the water transfer. Two potential energy barriers emerge in [TRA(H(2)O)(1)](+) along the intrinsic reaction coordinate of the water transfer. The water transfer event observed in [TRA(H(2)O)(1)](+) is not an elementary but a complex process.

The S1-S0 fluorescence excitation spectra of 5-chlorotropolone-M1 (M = Kr, Xe, CH4) van der Waals (vdW) complexes in the region near the electronic origin have been measured in a supersonic free jet to investigate the effect of the vdW interactions on proton tunneling. Tunneling splittings have been observed in the vdW vibrations as well as in the 000 transitions of the Kr and Xe complexes. The 000 tunneling splitting of the 5-chlorotropolone-(CH4)1 complex is significantly smaller than those of the Kr and Xe complexes. It has been suggested that the vdW vibrations couple with intramolecular motions, leading to a higher potential energy barrier to tunneling in the CH4 complex. The results of the 5- chlorotropolone complexes have been compared to those of the tropolone complexes.

A method used in analysis of dynamic behavior and machine performance on a free-piston-type Vuilleumier cycle (FPVM) machine is constructed as a nonlinear numerical model, because of a force acting on the surface of the moving part from a working gas and viscous damping due to the working gas flow. This model consists of three equations of motion for a hot displacer, a cold displacer and a casing, which are solved simultaneously by the Adams-Moulton method, and an equation of the instantaneous working gas pressure obtained on the supposition of an isothermal analysis on the Vuilleumier cycle machine. The cold displacer of the FPVM machine is combined with the hot displacer by a gas spring. A vibration model for those displacers is newly presented to verify a gas spring mechanism. In addition, self-excited vibration and forced vibration as to the FPVM heat pump are investigated.

We isolated mutant YM644, which showed elevated resistance to norfloxacin, ethidium bromide, acriflavine, and rhodamine 6G, from Pseudomonas aeruginosa YM64, a strain that lacks four major multidrug efflux pumps. The genes responsible for the resistance were mexHI-opmD. Elevated ethidium extrusion was observed with cells of YM644 and YM64 harboring a plasmid carrying the genes. Disruption of the genes in the chromosomal DNA of YM644 made the cells sensitive to the drugs.

Crystal structures of polymorphs of 2-(2'-hydroxyphenyl)benzimidazole (HPBI), Forms α and β, are analyzed by X-ray crystallography. The fluorescence excitation (FE) and fluorescence spectra of the polymorphs are separately observed at temperatures 77-298 K. It has been found that the electronic spectra of the two crystal forms are significantly different from each other. Photo-excitation of the enol forms in Forms α and β induces the excited-state intramolecular proton transfer (ESIPT) to produce the S(1) state of the keto forms. In the FE spectra of Forms α and β, the S(1) ← S(0) (ππ*) transition of the keto form is observed in the 360-420 nm region in addition to that of the enol form in the 250-420 nm region. In the FE spectrum of Form β a new band peaking at 305 nm is observed, which is assigned to the S(1) ← S(0) transition of a non-planar enol form based on the observation of dual fluorescence in the UV and visible regions and quantum chemical calculation on the transition energy against the twisted angle between the benzimidazole and hydroxyphenyl rings. The fluorescence quantum yield (φ(T)) for the keto form is remarkably dependent on polymorphs at room temperature; φ(T) = 0.53 for Form α is much larger than φ(T) ≤ 0.23 for Form β. At 77 K the φ(T) values for Forms α and β increase to 0.67 and ≤0.57, respectively. The changes in the φ(T) values are associated with the intramolecular charge transfer (ICT) state. The potential barrier height between the S(1)-keto and S(1)-ICT states is significantly lower for Form β than for Form α. At 77 K the S(1)-keto → S(1)-ICT process followed by S(1)-ICT → S(0)-keto internal conversion is significantly suppressed in Form β. We compare difference in the dynamics between Forms α and β in the electronic ground and excited states.

(1994). A Reconsideration of the Trials-Delay of Knowledge of Results Paradigm in Motor Skill Learning. Research Quarterly for Exercise and Sport: Vol. 65, No. 3, pp. 286-290.

The S1–S0 electronic spectra of 3,7‐dichlorotropolone, 3,5,7‐trichlorotropolone, and 3,7‐dibromotropolone have been measured in a supersonic free jet to investigate the effect on proton tunneling of symmetrical substitution of Cl or Br atoms for H atoms of tropolone. The 000 tunneling splittings in S1 of 3,7‐dichlorotropolone, 3,5,7‐trichlorotropolone, and 3,7‐dibromotropolone are 45, 31, and ≲1 cm−1, respectively. The increase of the tunneling splitting for 3,7‐dichlorotropolone compared to that for tropolone (19 cm−1) is attributed to a decrease in the O–H...O heavy atom separation, leading to smaller potential barrier height. The decrease of the 000 tunneling splitting for 3,5,7‐trichlorotropolone compared to 3,7‐dichlorotropolone and remarkable decrease of the 000 tunneling splitting for 3,7‐dibromotropolone are ascribed to significant changes of the normal coordinates compared to those of tropolone.

ESR absorption has been observed in a single-crystal solid solution of acenaphthene in durene under irradiation at 120K with light from a high-pressure mercury lamp. The observed hyperfine structure gives evidence for hyperconjugation of the ethylene group protons. The guest and host molecular planes are nearly parallel to each other, and the guest in-plane axes deviate from the host ones by ca 40°. For comparison, 1,1,2,2-tetradeuteroacenaphthene was also prepared and studied.

The S 1 -S 0 fluorescence excitation spectra of the tropolone-(CH 4 1 and 5-chlorotropolone-(CH 4 ) van der Waals complexes and their OD derivatives have been measured in a supersonic free jet. The 0 0 0 tunneling splittings of these complexes decrease significantly compared to the corresponding values of the bare molecules, suggesting that the effective height of the potential energy barrier increases in the S 1 states of the vdW complexes.

Cooke-Yarborough cycle (CY) machines are composed of several Stirling cycle (ST) machines and have some possibility as future external-combustion engines and/or thermally actuated heat pumps. This paper treats a CY machine with two displacers and one power piston, which is suitable for practical application. The method of CY machine analysis has been newly developed and applied to some examples. Analytical consideration shows that the CY machine is internally divided into a ST engine and a ST refrigerator in the same manner as a Vuilleumier cycle (VM) machine. The performance of the CY machine is almost equivalent to that of the VM machine under the specifications adopted in this paper, although these machines are considerably different in their pressure variation. The CY machine operates at its highest capacity when the power piston reciprocates with a delay of 90 degrees in the phase angle against the two displacers.

The 1st purpose of this study was to examine multiple electromyography (EMG) during voluntary hand movements. A secondary purpose was to investigate possible effects of pressure on intracortical inhibition (ICI) and intracortical facilitation (ICF) functions of the motor cortex, using paired-pulse transcranial magnetic stimulation. Twelve participants traced a 15-cm diameter target circle using a small laser pointer attached to the right index finger. After 5 acquisition trials, they performed 3 nonpressure trials followed by 3 pressure trials. The results showed that pressure had effects not only on agonist EMG activity but also on multiple muscles, such as synergist. In addition, a decrease in ICI and an increase in ICF were both observed under pressure for muscles other than the agonist.

The fluorescence excitation spectra of jet-cooled tropolone—Rg 1 (Rg  Ar, Kr, Xe) van der Waals complexes in the A 1 B 2 −X 1 A 1 region have been measured to investigate proton tunneling in the excited state of the complexes. We found that the intermolecular vibrations in the A 1 B 2 states of tropolone (OD)—Kr 1 and tropolone(OD)—Xe 1 couple with the proton motion.

The rotationally resolved zero-kinetic energy spectrum of benzene has been measured for ionization into the 61 level of the electronic ground state of benzene cation. Conclusive assignments have been given for the Jahn-Teller components j = 1/2 and j = ±3/2, arising from the linear and quadratic couplings.

A multisimulation model based on the isothermal analysis is developed, which is able to calculate the fundamental characteristics of ST and VM machines, and its effectiveness in the prediction of performance is inspected by comparing the calculated results with those obtained using the 3rd-order model. We clarify that the refrigerator and engine divided in the VM machine are both ST machines, and investigate the relationship between the characteristics of these ST machines and the VM machine

The primary purpose of the present study was to examine kinematic characteristics and force control during a golf-putting task under a pressure condition. The secondary purpose was to provide an exploratory investigation of the relationship between changes in behavior (kinematics and force control) and performance on the one hand, and psychological (attention and affect) and physiological (arousal level) changes on the other hand. Twenty male novices performed 150 acquisition trials, followed by 10 test trials during a pressure condition induced by performance-contingent distracters: a cash reward or punishment. A three-dimensional motion analysis revealed that, during the pressure test, angular displacements of rotational movements at the horizontal plane and movement time of the arms and club during the backswing and downswing phases all decreased, while acceleration of the elbows during the downswing phase increased. Mean performance indices in all participants’ were unchanged in spite of the kinematic changes under the pressure condition. Multiple regression analyses indicated that the decrement in performance, as well as increased variability of movement time and speed, were more likely to increase when participants shifted their attention to movements. Furthermore, changes in heart rate and negative affect were related to both the increase in movement acceleration and a decrease in grip force. These findings suggest that performance and behavioral changes during golf-putting under pressure can be associated with attentional changes, along with the influences of physiological-emotional responses.

The electronic spectra have been measured for jet‐cooled 3‐chlorotropolone in the S1–S0 region to investigate the effect of an asymmetric substitution on proton tunneling in tropolone. Both the 0++ and 0−− transitions have been identified in the fluorescence excitation spectrum, while no 0−+ or 0+− transition has been detected. This suggests that the double minimum potential energy function is almost symmetric for both S1 and S0. The tunneling doublet separations for the origin bands of 3‐chlorotropolone and its OD derivative have been measured to be 23 and 3 cm−1, respectively. These values are very similar to the corresponding values of 19 and 2 cm−1 for tropolone and its OD derivative, indicating that the substitution of a chlorine atom influences only a little on the strength of the intramolecular hydrogen bond.

C7H5C102, Mr = 156.6, monoclinic, P21/c, a = 8.476 (2), b = 12.241 (2), c = 8.170 (2) A, /3 -- 126.47 °, V= 681.7 A 3, z = 4, Dx = 1.525 g cm -3, A(Cu Ka) = 1.54184 A, /z = 44.63 cm-~, F(000) = 320, T = 293 K, R -- 0.046 for 833 reflections with I > 3tr(I). The hydroxylic proton forms a bifurcated hydrogen bond with carbonyl O atoms, one branch intramolecular and the other intermolecular. The latter intermolecular branches form a hydrogen- bonded dimer, which is roughly planar. Introduction. The structures of tropolone and some tropolone derivatives have been studied. It has been shown that 5,isopropyltropolone (Berg, Karlasson, (P~.tti & Wiehager, 1976) as well as tropolone manouchi & Sasada, 1973) forms a bifurcated hydrogen bond with the carbonyl O atoms, one branch being intramolecular and other intermolecu- lar. On the other hand, 4-isopropyltropone does not form a dimer, but O...O hydrogen bonds of 2.8 A link the molecules in a chain (Derry & Hamor, 1972). Very recently, we have measured the electronic spectra of the isolated 3-chlorotropolone (Tsuji, Sekiya, Nishimura, Mori & Takeshita, 1991) and 3-bromotropolone (Sekiya, Sasaki, Nishimura, Mori & Takeshita, 1990). The observation of tunnel splitting provides conclusive evidence for the de- localization of the proton. We have found that the hydroxylic proton is delocalized in 3-chlorotro- polone, whereas the proton is localized in 3- bromotropolone. It has been suggested that the localization of the hydroxylic proton strongly depends on the planarity of the molecule. In order to examine the effect of the substitution of a C1 atom on the molecular and crystal structure, an X-ray

Coordination structures of the Co(+)(NH(3))(n) and Ni(+)(NH(3))(n) ions are probed by infrared (IR) photodissociation spectroscopy with the aid of density functional theory (DFT) calculations. The IR spectra of N(2)-tagged Co(+)(NH(3))(n) (n = 1-4) exhibit two distinct bands assignable to the symmetric and antisymmetric NH stretches of the NH(3) molecules binding directly to Co(+). Size-dependent changes in the spectra of Co(+)(NH(3))(n) (n = 4-8) indicate that the first shell of Co(+) is filled with four NH(3) molecules and the resulting 4-coordinated structure forms the central core of further solvation. The spectra of Ni(+)(NH(3))(n) (n = 3-8) suggest that the coordination number of Ni(+) is also four, although a minor 3-coordinated isomer is identified for Ni(+)(NH(3))(4). Despite the same coordination number, the DFT calculations predict a distorted square-planar coordination for Ni(+)(NH(3))(4) and a distorted tetrahedral coordination for Co(+)(NH(3))(4). The coordination of Ni(+)(NH(3))(4) is explainable by using a simple model based on the geometry of a half-filled 3d orbital in Ni(+). This suggests that the Ni(+) ion gives priority to the minimization of the metal-ligand repulsion in accommodating four ligands in the first shell. On the other hand, the same model fails to explain the coordination of Co(+)(NH(3))(4). An interpretation for this is that the Co(+) ion gives priority to the minimization of the ligand-ligand repulsion.

Infections with gastrointestinal parasitic helminthes were historically surveyed from the Jomon period to the end of the Edo period in Japan. The parasitic helminthes whose eggs or symptoms were shown in the remains and bibliographies are the roundworm, whipworm, liver fluke, Yokogawa's fluke and the cestode, Diphyllobothrium sp. The first two are soil-transmitted nematodes and the other three parasitic helminths are those with which people are infected following eating raw fish. The infection routes provide valuable information on the environments, life-style and customs in those days. The eggs of the soil-transmitted parasites have the thick shells resistant to the environments. Humans are infected with the parasites after the eggs are orally ingested with soil, dust, vegetables grown with night soil or manure. When the custom of the night soil was started in the history of Japan was discussed with this infection route. In ancient times, feces are thought to have been discarded. In the Medieval Period, they were started to be used as a fertilizer. No mature types of manure were used until the modern times (already in the Edo period). To our idea, no recoveries of eggs of hookworms causing severe anemia do not necessarily mean that people were not infected with the parasites in those days because the eggs are covered with thin shells liable to rupture. The latter fact of the eggs of the platihelminths, C. sinensis, M. yokogawai and D. latum has something to do with Japanese traditional eating customs, unequivocally demonstrating that they ate raw fish from the Nara Period, at latest, until today. Whether eggs of the cestode (D. latum) are found in Jomon remains, Momijiyama Iseki, Hokkaido should be investigated. If no eggs of the cestode are found in their toilet site or elsewhere, it could be concluded that they did not have the custom of eating raw salmon. Such a conclusion would be itself a new fact. One of the effective treatments for the cestode (D. latum) sometimes still carried out in the 21st century in Japan, is binding worms from the anus using chopsticks. This method can be traced back to the Edo period as far as this investigation is concerned. Though the historical studies on anthelmintics are in progress, there seem to be no effective anthelmintics leaving nothing to be desired to the present authors' knowledge.

The S1–S0 fluorescence excitation and dispersed fluorescence spectra have been measured for jet‐cooled 5‐bromotropolone (5BTR‐h), 5‐chlorotropolone (5CTR‐h), and their OD derivatives in order to investigate substituent effects on proton tunneling. Both the 0++ and 0−− transitions were identified in the fluorescence spectra of these molecules. The tunneling doublet splittings in the electronic origin band of 5BTR‐h (16 cm−1) decreased by 4 cm−1, whereas that of 5CTR‐h (23 cm−1) increased by 3 cm−1 as compared with tropolone (TRN‐h). Relatively small deviation in the tunneling separations for these molecules from that for tropolone is ascribed to conjugation in the S1 state. An electron‐withdrawing character of chlorine and bromine atoms is almost canceled by a conjugative electron‐releasing effect.