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The key parameter to discuss the possibility of the pion condensation in nuclear matter, i.e., the so-called Landau-Migdal parameter g^{'}, was extracted by measuring the double-differential cross sections for the (p,n) reaction at 216 MeV/u on a neutron-rich doubly magic unstable nucleus, ^{132}Sn with the quality comparable to data taken with stable nuclei. The extracted strengths for Gamow-Teller (GT) transitions from ^{132}Sn leading to ^{132}Sb exhibit the GT giant resonance (GTR) at the excitation energy of 16.3±0.4(stat)±0.4(syst) MeV with the width of Γ=4.7±0.8 MeV. The integrated GT strength up to E_{x}=25 MeV is S_{GT}^{-}=53±5(stat)_{-10}^{+11}(syst), corresponding to 56% of Ikeda's sum rule of 3(N-Z)=96. The present result accurately constrains the Landau-Migdal parameter as g^{'}=0.68±0.07, thanks to the high sensitivity of the GTR energy to g^{'}. In combination with previous studies on the GTR for ^{90}Zr and ^{208}Pb, the result of this work shows the constancy of this parameter in the nuclear chart region with (N-Z)/A=0.11 to 0.24 and A=90 to 208.

We perform the first direct mass measurements of neutron-rich calcium isotopes beyond neutron number 34 at the RIKEN Radioactive Isotope Beam Factory by using the time-of-flight magnetic-rigidity technique. The atomic mass excesses of ^{55-57}Ca are determined for the first time to be -18650(160), -13510(250), and -7370(990) keV, respectively. We examine the emergence of neutron magicity at N=34 based on the new atomic masses. The new masses provide experimental evidence for the appearance of a sizable energy gap between the neutron 2p_{1/2} and 1f_{5/2} orbitals in ^{54}Ca, comparable to the gap between the neutron 2p_{3/2} and 2p_{1/2} orbitals in ^{52}Ca. For the ^{56}Ca nucleus, an open-shell property in neutrons is suggested.

The (^{12}N, ^{12}C) charge-exchange reaction at 175 MeV/u was developed as a novel probe for studying the isovector spin giant monopole resonance (IVSMR), whose properties are important for better understanding the bulk properties of nuclei and asymmetric nuclear matter. This probe, now available through the production of ^{12}N as a secondary rare-isotope beam, is exothermic, is strongly absorbed at the surface of the target nucleus, and provides selectivity for spin-transfer excitations. All three properties enhance the excitation of the IVSMR compared to other, primarily light-ion, probes, which have been used to study the IVSMR thus far. The ^{90}Zr(^{12}N,^{12}C) reaction was measured and the excitation energy spectra up to about 70 MeV for both the spin-transfer and non-spin-transfer channels were deduced separately by tagging the decay by γ emission from the ^{12}C ejectile. Besides the well-known Gamow-Teller and isobaric analog transitions, a clear signature of the IVSMR was identified. By comparing with the results from light-ion reactions on the same target nucleus and theoretical predictions, the suitability of this new probe for studying the IVSMR was confirmed.

Made available in DSpace on 2013-08-12T19:03:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-01 Made available in DSpace on 2013-09-30T18:47:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:57:06Z No. of bitstreams: 0 Made available in DSpace on 2014-05-20T13:57:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) In the present work, we analyzed the histochemical aspects of Passiflora edulis seeds reserve mobilization during the first ten days of germination. Our results showed that mainly lipids present in the endosperm are used as a reserve source, and their levels reduce at the same time the radicle protrudes, between the fourth and sixth day of sowing. Furthermore, protein bodies are present in the cotyledons, which are degraded as germination occurs and are almost depleted by the time of radicle protrusion. Starch grains also appear in the late germination period, and it is not clear if there is any reserve wall polysaccharide consumption in the endosperm. UNESP Univ Estadual Paulista, Lab Fotomorfogenese Plantas, Dept Bot, Inst Biociencias, Rio Claro, SP, Brazil UNESP Univ Estadual Paulista, Lab Fotomorfogenese Plantas, Dept Bot, Inst Biociencias, Rio Claro, SP, Brazil

Surface modification of luminescent nanomaterials has attracted considerable technological interest. With decreasing particle size, the passivation of surface defects is of vital importance. This paper reports the effect of an alkali (KOH) solution treatment and organic functional groups on the luminescence efficiency and particle dispersibility. Fourier transform infrared spectroscopy provided clear evidence of surface modification with organic functional groups from the C=O , C–H , and C–O stretching modes at 1740, 1365, and 1218 cm-1. The KOH-treated sample showed a 40% increase in luminescence intensity, whereas 87% increase in luminescence intensity was obtained from the dispersion-agent-containing sample. To the best of our knowledge, this is the highest efficiency improvement for sub-micrometer-sized BAM: Eu2+ phosphors reported thus far.

統合的機能である排便反射は主として直腸―直腸収縮反射と直腸―内肛門括約筋弛緩反射より引きおこされている. 直腸の適度な加圧伸展は, 伸展部位の収縮反射とそれと同期した内肛門括約筋の弛緩反射をおこす. 両反射は, (1) 骨盤神経を介する仙髄レベルの促進反射, (2) 結腸神経を介する腰髄レベルの抑制反射および (3) 壁内神経系を介する内反射によって制御されている. これらの反射は (4) 求心路を骨盤神経とする橋排便反射中枢を介する腰髄での結腸神経活動の抑制機構で制御されている. 直腸における糞便の貯留には腰髄レベルの抑制反射が関与し, 排便時にはこの抑制反射の脱抑制が鍵となる. これらの反射経路の可塑性は, 外反射経路が損傷されても内反射のみで十分な排便機能が発現することや, 内反射経路が損傷されても, 無傷群と同程度まで回復するという高木らの実験結果によって立証された. その可塑性を利用した肛門機能温存のための新治療法をはじめとしていくつかの可能性を示唆した.

A candidate resonant tetraneutron state is found in the missing-mass spectrum obtained in the double-charge-exchange reaction ^{4}He(^{8}He,^{8}Be) at 186 MeV/u. The energy of the state is 0.83±0.65(stat)±1.25(syst) MeV above the threshold of four-neutron decay with a significance level of 4.9σ. Utilizing the large positive Q value of the (^{8}He,^{8}Be) reaction, an almost recoilless condition of the four-neutron system was achieved so as to obtain a weakly interacting four-neutron system efficiently.

Corrosion behavior of modified SUS316 has been studied under different oxygen potentials with tellurium vapor. Under the condition of oxygen potential ⩽−500 kJ/mol and tellurium vapor pressure of 8.9 × 10 −4 atm, duplex corrosion layers formed on the surface of specimens, which mainly consisted of chromium telluride, iron telluride and chromium oxide. The thickness of corrosion layer was increased with decreasing the oxygen potential. Furthermore, the amount of oxygen uptake in sample corroded with tellurium vapor was much greater than that in sample oxidized without tellurium vapor.

Oxidation behaviors of modified SUS316 (PNC316) and SUS316 stainless steels were investigated under the low oxygen partial pressure of 10 −31 −10 −22 atm at 600–800 °C. Oxygen uptake by these materials parabolically increased with time, and the kinetic rate constants depended on both oxygen partial pressure and temperature. Thus, semi-empirical equations of the parabolic rate constants were obtained to be 2.70×10 4 exp(−109/ RT ) P O 2 0.279 for PNC316 and 9.23×10 4 exp(−98/ RT ) P O 2 0.313 for SUS316. For the duplex layer formed under the low oxygen partial pressure, the inner layer consisted of such oxides as Cr 2 O 3 and FeCr 2 O 4 , while the outer layer consisted of non-oxidized α-Fe. Furthermore, oxidation along the grain boundaries was observed for samples oxidized for a long time. From the point of view of fuel cladding chemical interaction evaluation at high burn-up fuel for fast reactors, it is interesting that formation of non-oxidized α-Fe was observed under the low oxygen partial pressure.

In Japan, the treatment of waste concrete scraps has been one of the environmental issues. Therefore, new application using pulsed power discharge has been developed as the recycling method of the coarse aggregates from the waste concrete scraps. In the work, the dependences of the quality of the recycled coarse aggregate by the repetitive pulsed discharge treatments on the consumption energy were investigated. As the results, it was clear that the quality of the recycled coarse aggregate could be controlled by the number of discharge treatments. The recycled coarse aggregate, which satisfied class H under the regulations of Japan Industrial Standard (JIS A5005 and JIS A5021), was produced with the smallest consumption energy when the discharged energy from 0.02 μF of capacitor charged up to 400 kV applied to the waste concrete scraps during single discharge treatment.

To alleviate potentially catastrophic water supply and wastewater disposal problems as well as expand dependable water supply infrastructure, Japan has launched comprehensive urban wastewater reclamation and reuse projects since 1968. In this paper, the status of national policies on wastewater treatment, wastewater reuse characteristics, and some wastewater reuse experiences are presented. Two implementation examples in Tokyo and Fukuoka are discussed in detail, with special reference to application for toilet-flushing in high-rise business buildings and stream restoration and flow augmentation. It was found that the key to the success of wastewater reclamation and reuse is the quality of reclaimed water; public acceptance is closely associated with water quality and water supply dependability.

A second-generation core DSP suited for digital audio applications has been developed. The first DASP (digital audio signal processor) with the core-DSP implements the dedicated audio, host, and external memory interfaces. The DSP, which is the central processing role in the Hi-Fi audio systems, has been specifically developed by many LSI manufacturers. The manufacturers in the consumer market always require low cost devices. This new DASP has been enhanced with many new functions, which are discussed.

Some studies have reported a decreased absorption of mycophenolic acid (MPA) from mycophenolate mofetil (MMF) in renal transplanted (RTx) patients under proton-pump inhibitors (PPIs). There is still a lack of information regarding (1) whether this effect occurs when MMF is administered with either tacrolimus or cyclosporine A [calcineurin inhibitors (CNIs)], (2) whether the effect has the same amplitude during the first year after RTx, and finally (3) whether this decrease in exposure is clinically relevant.We retrospectively analyzed the omeprazole effect in 348 12-hour pharmacokinetic samplings [area under the curve (AUC)(0-12h)] performed on days 7, 14, 30, 60, 180, and 360 after RTx in 77 patients who participated in previous trials.For all periods, the groups with and without PPI did not differ in all variables. By mixed-model analysis of variance, PPI reduced the MPA AUC(0-12h) (P0.0008) in the patients under both CNIs mainly due to decreased absorption (P = 0.049). In the tacrolimus group, a lower exposure seemed also due to a decreased MPA reabsorption at 10-12 hours. The PPI effect remains throughout the first year but was clinically more important on day 7. By Cox analysis, the use of PPI was associated with a 25% less chance of being adequately exposed to MPA (95% confidence interval 0.58-0.99, P = 0.04). Similarly, the number of patients underexposed to MPA (AUC30 ng·h/mL) was higher at most periods in the PPI group but again not statistically significant.These data indicate that PPI decreases the MPA exposure when associated with both CNIs but particularly in the first week after RTx. In this period, the MMF dose should be increased. This effect lasts throughout the first year but does not seem to be clinically relevant after the first week.

Nipradilol (3,4-dihydro-8-(2-hydroxy-3-isopropylamino) propoxy-3-nitroxy-2H-1-benzopyran) is a newly synthesized chemical agent designed to possess beta-adrenoceptor blocking and vasodilating actions. Nipradilol decreased left ventricular contractility index (Emax, slope of the ventricular end-systolic pressure-volume relation), systolic pressure-volume area (PVA, a measure of ventricular total mechanical energy) and oxygen consumption in cross-circulated excised dog hearts. However, nipradilol did not decrease total coronary resistance. These results indicate that nipradilol, like propranolol, depresses myocardial mechanoenergetics and that the vasodilating action of nipradilol could not be detected in the present study.

It was recently reported that some 5-HT(4)-receptor agonists increased neuronal numbers and length of neurites in enteric neurons developing in vitro from immunoselected neural crest-derived precursors. We aimed to explore a novel approach in vivo to reconstruct the enteric neural circuitry that mediates a fundamental distal gut reflex.The neural circuit insult was performed in guinea pigs by rectal transection and subsequent end-to-end one layer anastomosis. A 5-HT(4)-receptor agonist, mosapride citrate (10-100 micromol L(-1)) (applied for a patent) was applied locally at the anastomotic site.Mosapride promoted the regeneration of the neural circuit in the impaired myenteric plexus and the recovery of the defecation reflex in the distal gut. Furthermore, mosapride generated neurofilament (NF)-, 5-HT(4)-receptor- and 5-bromo-2'-deoxyuridine (BrdU)-positive cells and surprisingly formed neural network in the newly formed granulation tissue at the anastomotic site 2 weeks after enteric nerve circuit insult. Possible neural stem cell markers, anti-distal less homeobox 2 (DLX2)- and p75-positive and NF-positive cells increased during the same time period. All actions by mosapride were inhibited by the specific 5-HT(4)-receptor antagonist, GR113808 (10 micromol L(-1)).These results indicate that activation of enteric neural 5-HT(4)-receptors promotes reconstruction of an enteric neural circuit leading to the recovery of the defecation reflex in the distal gut, and that this reconstruction involves possibly neural stem cells. These findings indicate that treatment with 5-HT(4) agonists could be a novel therapy for generating new enteric neurons to rescue aganglionic gut disorders.

The development of a new recycling technology for waste concrete scraps becomes a big issue in Japan due to the increase of the scraps and the decrease of the natural coarse aggregates. In the present work, a new technology of concrete aggregates recycling using pulsed discharges was performed. A Marx generator was used as a pulsed power source and a point to hemisphere mesh configuration electrode was immersed in water. The pulsed voltages were applied to the concrete scraps which placed on hemisphere mesh and the discharges passes were occurred inside of concrete scraps as the result of the electrical breakdown. Immediately after the breakdown, the concrete scraps were broken by the shockwave due to the volumetric thermal expansion of the discharge pass. After the repetitive discharge treatments, the recycled coarse aggregates were evaluated. From our previous results, the quality of the recycled coarse aggregates such as the oven-dry density, the water absorption ratio, and the fineness modulus were controlled by the energy consumption of discharge treatments. In this work, the effects of the gap distance between high voltage point electrode and concrete surface was discussed. The results showed that the optimum condition was obtained in case that the high voltage point electrode always comes in contact with the target concrete.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:42:29Z No. of bitstreams: 1 S1519-69842010000100019.pdf: 665773 bytes, checksum: 4a0751716b6985fdc6b340f22d1ea491 (MD5) Made available in DSpace on 2013-08-22T18:42:29Z (GMT). No. of bitstreams: 1 S1519-69842010000100019.pdf: 665773 bytes, checksum: 4a0751716b6985fdc6b340f22d1ea491 (MD5) Previous issue date: 2010-02-01 Made available in DSpace on 2013-09-30T19:29:48Z (GMT). No. of bitstreams: 2 S1519-69842010000100019.pdf: 665773 bytes, checksum: 4a0751716b6985fdc6b340f22d1ea491 (MD5) S1519-69842010000100019.pdf.txt: 44175 bytes, checksum: bed19631380591e613f9f2ad1179dd73 (MD5) Previous issue date: 2010-02-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:08:10Z No. of bitstreams: 2 S1519-69842010000100019.pdf: 665773 bytes, checksum: 4a0751716b6985fdc6b340f22d1ea491 (MD5) S1519-69842010000100019.pdf.txt: 44175 bytes, checksum: bed19631380591e613f9f2ad1179dd73 (MD5) Made available in DSpace on 2014-05-20T15:08:10Z (GMT). No. of bitstreams: 2 S1519-69842010000100019.pdf: 665773 bytes, checksum: 4a0751716b6985fdc6b340f22d1ea491 (MD5) S1519-69842010000100019.pdf.txt: 44175 bytes, checksum: bed19631380591e613f9f2ad1179dd73 (MD5) Previous issue date: 2010-02-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) As respostas de germinação de sementes de Hylocereus setaceus para incubações isotérmicas sob diferentes potenciais de água foram analisadas utilizando-se modelos de graus dia e psi dia, com o objetivo de descrever alguns parâmetros da população e para testar a viabilidade do modelo para descrever as respostas da semente a temperatura e potencial de água. Sementes de H. setaceus germinaram relativamente bem em uma ampla faixa de temperaturas e a germinação foi limitada pela velocidade nos intervalos de 11 a 20 °C, e de 30 até 40 °C, nos quais a velocidade de germinação aumenta e diminui, respectivamente, com a temperatura. A temperatura mínima ou base (Tb) para germinação de H. setaceus foi 7 °C, e a temperatura máxima variou de 43,5 a 59 °C dependendo da fração percentual, com média de 49,8 °C. O número de graus dia necessário para 50% das sementes germinarem na faixa de temperatura infra-ótima foi de 39,3 °C dia, enquanto que, no intervalo supra-ótimo o valor de 77 °C dia foi assumido como constante para todo o intervalo. A germinação foi sensível à diminuição do ψ no meio, e tanto a germinabilidade como a velocidade de germinação mudaram negativamente com a redução do ψ, sendo que a taxa de redução mudou com a temperatura. Os potenciais base de água (ψb(g)) tendem a zero com o aumento da temperatura e essa variação se reflete no efeito relativamente maior do ψ sobre a germinação na faixa supra-ótima de temperatura. No geral, o modelo descreveu melhor as curvas de germinação em potenciais de água baixos do que em altos. As análises também sugerem que Tb pode não depender do ψ e que o ψb(g) pode mudar em função da temperatura na faixa infra-ótima de temperatura. The germination response of Hylocereus setaceus seeds to isothermic incubation at different water potentials was analysed by using the thermal time and hydrotime models, aiming to describe some germination parameters of the population and to test the validity of the models to describe the response of the seeds to temperature and water potential. Hylocereus setaceus seeds germinated relatively well in a wide range of temperatures and the germination was rate limited from 11 to 20 °C interval and beyond 30 °C until 40 °C, in which the germination rate respectively shifts positively and negatively with temperature. The minimum or base temperature (Tb) for the germination of H. setaceus was 7 °C, and the ceiling temperature varied nearly from 43.5 to 59 °C depending on the percent fraction, with median set on 49.8 °C. The number of degrees day necessary for 50% of the seeds to germinate in the infra-optimum temperature range was 39.3 °C day, whereas at the supra-optimum interval the value of θ = 77 was assumed to be constant throughout. Germination was sensitive to decreasing values of ψ in the medium, and both the germinability and the germination rate shift negatively with the reduction of ψ, but the rate of reduction changed with temperature. The values of base water potential (ψb) shift to zero with increasing temperatures and such variation reflects in the relatively greater effect of low ψ on germination in supra optimum range of T. In general, the model described better the germination time courses at lower than at higher water potentials. The analysis also suggest that Tb may not be independent of ψ and that ψb(g) may change as a function of temperature at the infra-otimum temperature range. Fundação de Ensino e Pesquisa de Itajubá Universidade Estadual Paulista Instituto de Biociências Departamento de Botânica Universidade Estadual Paulista Instituto de Biociências Departamento de Botânica

Capsaicin-sensitive and hexamethonium-insensitive contractile and relaxatory motor responses of circular muscle induced by mesenteric nerve stimulation were studied. Desensitization to substance P or to neurokinin A, or the substance P antagonist, spantide largely reduced the initial contractile response. Desensitization to calcitonin gene-related peptide moderately reduced the late prolonged relaxation response. These results indicate that both responses of the circular muscle to mesenteric nerve stimulation may be attributed to a release of neuropeptides evoked by the 'efferent' stimulation of capsaicin-sensitive sensory nerves.

In the present study, tryptamine produced a slow hyperpolarization in a few neurons other than a slow depolarization in myenteric neurons of the isolated guinea-pig ileum. Neither the adrenergic neuron blocker, guanethidine nor the 5-hydroxytryptamine uptake inhibitor, zimelidine, which can inhibit the release of 5-hydroxytryptamine from enteric neurites induced by tryptamine (M. Takaki et al. (1985) Neuroscience 16, 223-240), affected this slow hyperpolarization. Therefore, it was concluded that the slow hyperpolarization induced by tryptamine in myenteric neurons was not mediated via the release of 5-hydroxytryptamine or noradrenaline. It might be possible that the hyperpolarization was induced by a direct action of tryptamine on myenteric neurons per se.

Technology fusion between motor design and control can produce new applications. This paper introduces a saliency-based sensorless drive of adequate designed IPM motor for a specific application in a robot vehicle. The motor is designed considering both configuration so as to fit to the application and the electromagnetic feature to be better adapted to saliency-based sensorless control. The speed and position synchronous control for each wheel-motor in entire speed ranges including zero speed is realized by a single motion controller and drive-amps for individual motors. Finally, two types of robot vehicle, one being a two-wheel deferential drive and the other being an omni direction drive, are developed to transport objects and human. The paper mainly focuses on the concept of motor design and its control. Some analysis and test data are shown in this paper.

Carbon microcoils (CMCs) with 3D-helical/spiral conformations were embedded into various elastic matrices, such as polysilicone, elastic epoxy resin, etc., to produce CMC tactile and nearness micro-sensory elements. The sensing properties of the CMC sensor element (changes in electrical parameters under an applied load (pressure) or approaching substances) were examined. The sensing ability was obtained even for microelements of 0.1 × 0.1 × 0.1 mm3 or 0.05 mm thickness, and for a small added amount of 0.1 wt% CMCs in the matrix. The minimum detection pressure was ca. 1 Pa. Changes in the L, C, R or Z parameter were also observed by approximating a hand, heater, mobile phone, sound, etc. It was considered that the CMC sensor elements have high potential applications, such as tactile sensors for endoscopes, catheters, a manipulation sheet, or as the artificial skin with a high tactile sensing ability and/or as nearness sensors for humanoid robots, etc.

Made available in DSpace on 2011-04-09T15:52:52Z (GMT). No. of bitstreams: 1 28501.pdf: 142815 bytes, checksum: 3ad0b32a2daf426e914a60c427a0a1f5 (MD5) Previous issue date: 2006-03-20

In the development of miniature opening and closing mechanism, piezoelectric element has been used as its actuator. This mechanism, however, tends to become larger and complicated as it needs a mechanism for displacement enlargement because of the infinitesimal output displacement. Therefore, an attempt applying buckling phenomenon of long column to the opening and closing mechanism of finger has been made. An elastic member with a long strip shape was bent in the shape of M character, both ends fixed and reciprocating translational drive was imparted to the V-shaped common portion at the center. As a result, a simple miniature gripper with large rate of bending displacement at the finger tip to a translational displacement at the center, namely the enlargement rate of the displacement, has been developed. In this study, in addition to the element technology development for product, such improvements as increasing of the rate of gripping force to driving tensile force on the finger, that is, gripping efficiency were aimed. The results obtained are as follows. (1) Hinge joints on supporting portions at both ends or the mid common portion of the fingers decrease the driving tensile force beginning to grip. They, however, little contribute to the improvement of the gripping efficiency. (2) Crossing an operating member at the center in the shape of × character so as to enlarge an angle of the operating members to the finger increases the gripping efficiency. The enlargement rate of the displacement, however, decreases, so that the angle should be decided based on the object. (3) Free support of an intermediate portion on a lateral surface of the finger allows the change of the gripping efficiency. When bending deformation outside at the center in length of the finger is restrained, the gripping efficiency increases by about 2 times.Copyright © 2006 by ASME

A display system requiring no special glasses is useful for 3D images. The parallax barrier display system has superior characteristics, such as having a planar screen and a thin panel. However, a conventional parallax barrier display system has disadvantages such as having images with divided horizontal resolution. We describe a newly developed stereoscopic 3D display with a parallax polarizer barrier. The advantage of the parallax polarizer barrier is that the resolution of presented parallax images is much greater than that of a conventional display and see-through 3D images can be observed, because the 3D screen can multiplex projected images with horizontal and vertical polarization to display stereo views.

We have proposed an active hydrogen reduced water theory that active hydrogen produced by electrolysis of water is stabilized in the form of hydrogenated metal nanocolloids in electrolyzed reduced water (ERW) and scavenges intracellular reactive oxygen species (ROS). Because various brain diseases are caused by oxygen stress, we examined the effect of ERW on oxidative stress-induced apoptois of neuronal cells. ERW suppressed the H2O2-induced cell death of mouse neuroblastoma N1E115 cells, rat pheochromocytoma PC12 cells and mouse neuronal stem SFME cells. ERW lowered the intracellular ROS level of N1E115 cells, suppressing the H2O2-induced decrease of mitochondrial membrane potential and intracellular ATP level, which are markers of apoptosis. These results suggested the effectiveness of ERW for prevention of various brain diseases caused by oxidative stress.

Made available in DSpace on 2022-04-28T19:56:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-01-01 The germination of seeds of Psidium guajava L. (Myrtaceae) is controlled by phytochrome. Guava seeds can germinate with at least one hour per day of irradiation of high red:far-red ratio light preceeded or followed by shade light, indicating that phytochrome B controls germination in these conditions. Under alternating temperatures, in a range of at least 5°C, seeds will germinate in darkness, suggesting that in gaps of the canopy, when seeds are covered by a thin layer of soil they will germinate once the alternating temperatures are experienced. Under these conditions phytochrome A is responsible for the control of guava seed germination. Departamento de Botânica UNESP, CP 199, 13506-900, Rio Ciaro, SP Departamento de Botânica UNESP, CP 199, 13506-900, Rio Ciaro, SP

Electrolyzed-reduced water (ERW) produced by electrolyzing water in cathode side has the ability to scavenge reactive oxygen species (ROS). Here, we investigated the effect of ERW on oxidative stress-induced neural cell death by glutamate. When cell viability assay was performed using primary rat cerebral cortical culture as neural model, ERW suppressed neural cell death by glutamate. Furthermore, intracellular ROS levels were reduced by ERW, suggesting that suppressive effect of ERW on the glutamate-induced neural cell death was due to the suppression of glutamate-induced ROS augmentation by ERW.

Two functionally different MAP kinase phosphatases (MKPs) were investigated to clarify their roles in behavioral sensitization to methamphetamine (METH). MKP-1 mRNA levels increased substantially by about 60-300% in a range of brain regions, including several cortices, the striatum and thalamus 0.5-1 h after acute METH administration. After chronic METH administration its increase was less pronounced, but a more than 50% increase was still seen in the frontal cortex. MKP-1 protein levels also increased 3 h after acute or chronic METH administration. MKP-3 mRNA levels increased by about 30-50% in several cortices, the striatum and hippocampus 1 h after acute METH administration, but only in the hippocampus CA1 after chronic METH administration. Pre-treatment with the D(1) dopamine receptor antagonist, SCH23390, attenuated the METH-induced increase of MKP-1 and MKP-3 mRNA in every brain region, while pre-treatment with the NMDA receptor antagonist, MK-801, attenuated it in some regions. These findings suggest that in METH-induced sensitization, MKP-1 and MKP-3 play important roles in the neural plastic modification in widespread brain regions in the earlier induction process, but in the later maintenance process, they do so only in restricted brain regions such as MKP-1 in the frontal cortices and MKP-3 in the hippocampus.

Using a "hybrid logistic function," we attempted to develop a new approach for a quantitative and comprehensive evaluation of the force-time curve of guinea pig gut contractions. We recorded ileum twitch and proximal colon spontaneous isometric longitudinal contractions because of their high regularities. We digitized the force-time curves of both contractions and performed curve fitting to them by hybrid logistic functions with a personal computer. We found that the fitness of these functions to both contractions was excellent. The respective best-fit parameters of these functions were closely correlated with the observed mechanical indexes, all of which are physiologically meaningful. This result suggests the possibility that these parameters can characterize the magnitudes and time courses of F(t) curves of the intestinal contractions. Furthermore, it might be able to show an effect of a pharmacological agent specifically either on the contraction phase, the relaxation phase, or other parameters of each. Therefore, we insisted that the present new approach for evaluating gut motility is promising for clinical application.

We briefly review that ventricular systolic pressure-volume area (PVA) can predict changes in myocardial O2 consumption (VO2) associated with cardiac work production (positive work) and absorption (negative work). PVA represents the total mechanical energy of cardiac contraction as it is an integral of mechanical energy generated during systole in the cardiac chamber. We have shown that PVA linearly correlates with VO2 under varied pre- and afterload conditions in the left ventricle of the excised cross-circulated canine heart preparation as well as other heart preparations of different species. PVA is the sum of external mechanical work (EW) and mechanical potential energy (PE) which is almost fully convertible to mechanical work without affecting VO2. To compare the energetic effects of cardiac work production and absorption, we varied the timing of the servo pump motion relative to left ventricular (LV) contraction. When the pump fills the LV during diastole and sucks (allows ejection) during systole, cardiac work is produced by the heart, and hence EW0. When the pump fills the LV during systole and sucks during diastole, work is absorbed by the heart, and hence EW0. The pressure-volume loop rotates counterclockwise when EW0. It rotates clockwise when EW0. As the result, PVA (= PE + EW)PE when EW0; PVAPE when EW0. We found that VO2 always linearly correlated with PVA regardless of the polarity of EW. Therefore, PVA is the unique determinant of VO2 in a cardiac chamber in a stable contractility.

We have recently established a new measurement system of myocardial O2 consumption per min (mVO2) of mechanically unloaded rat left ventricular (LV) slices (Yasuhara et al.: Am. J. Physiol. 270: H1063-H1070, 1996). Using this system, we have revealed that an increment in O2 consumption (delta mVO2) by electrical stimulation primarily represents mVO2 for Ca2+ handling in the excitation-contraction (E-C) coupling, though much smaller than that in the whole heart preparation. The much smaller delta mVO2 in the sliced myocardium than that in the whole heart is due to the much lower frequency of stimulation (60 bpm against 300 bpm). We consider that delta mVO2 does not contain mVO2 for residual crossbridge cycling from the results showing no effect of 2,3-butanedione monoxime on delta mVO2 despite the large decrease in mechanically unloaded contraction, which is expressed by the motility index. We also revealed that mVO2 without stimulation represents basal metabolism. The basal metabolism in rat myocardial slices, which is much higher than in other mammalian hearts, corresponds to that in the rat whole heart preparation. We finally obtained the results showing that sarcoplasmic reticulum (SR) Ca2+ pump blockers, thapsigargin and cyclopiazonic acid, did not reduce basal metabolic mVO2 but both of them reduced delta mVO2 maximally by 50-70% of control and markedly reduced the motility index. We conclude that myocardial O2 consumption (VO2) is composed of VO2 for E-C coupling and basal metabolism and does not contain VO2 for residual crossbridge cycling. Basal metabolic VO2 does not include VO2 for the SR Ca2+ pump, and at least two-thirds of VO2 for E-C coupling represents VO2 for the SR Ca2+ pump.

The effect of water stress induced by application of polyethylene glycol 6000 during seed germination and seedling growth ofOryza sativa L. cv. IAC 165 was analysed. The seed germination was inhibited by the decrease in the water potential of the medium, the inhibition being greater under white light than under continuous darkness. When the seedling was submitted to water stress (-0.51 MPa) white light inhibited growth of root, coleoptile-and leaf, while under no stress conditions white light caused increase in growth of root and leaf and only inhibition of coleoptile growth.

The mechanisms underlying the negative inotropic effects of isoflurane are incompletely understood. One suggested mechanism is that isoflurane may decrease Ca2+ sensitivity of contractile proteins. If so, more free calcium would be needed to activate contractile proteins to the same degree, which would impose a greater requirement for myocardial oxygen consumption used in the cycling of calcium. In this study, the authors use the excised, cross-circulated, canine heart model and the volume servopump technique to measure the effects of isoflurane on Emax (a contractile index) and on the relationship between pressure-volume area (PVA, a measure of total mechanical energy) and myocardial oxygen consumption per beat (VO2).Effects of intracoronary isoflurane infused via a precoronary oxygenator on myocardial mechanoenergetics were studied during isovolumic contractions. The authors measured left ventricular (LV) pressure, LV volume, coronary flow, and arteriovenous oxygen content difference and computed Emax, VO2 and PVA at 0, 1.0, 1.5, and 2.0% isoflurane. From these data, the authors obtained oxygen costs of PVA and Emax in control subjects and in those receiving 2.0% isoflurane.Emax, PVA, and VO2 dose-dependently decreased by similar degrees (P0.05). Isoflurane did not change the oxygen costs at 1.5% and 2.0% concentration (P0.05).These mechanoenergetic findings suggest that the primary method by which isoflurane decreases contractility is not by decreasing Ca2+ sensitivity of contractile proteins but mainly by decreasing Ca2+ handling in the excitation-contraction coupling without myocardial oxygen wasting effect.

We investigated rat left ventricular (LV) mechanoenergetics in three different preparations. We obtained an upward convex curvilinear end-systolic pressure-volume relation (ESPVR) regardless of left ventricular (LV) contractility in in situ and excised cross-circulated rat hearts. We also obtained a linear myocardial O2 consumption per beat (VO2)-end-systolic pressure-volume area (PVA; a measure of ventricular total mechanical energy) relation regardless of the curvilinear LV ESPVR in the excised cross-circulated heart. The slope and the VO2 intercept of the VO2-PVA relation was similar to those in other species. The basal metabolism obtained by KCl arrest was higher than those in other species. In the whole heart preparation, the VO2 intercept may include O2 consumption for residual crossbridge cycling as well as O2 consumption for excitation-contraction (E-C) coupling and basal metabolism. Therefore, we established a new system for measuring myocardial O2 consumption of mechanically unloaded (zero PVA) rat LV slices. The increment in O2 consumption by stimulation of the slices represents O2 consumption for E-C coupling (but not for crossbridge cycling). Most O2 consumption for E-C coupling seems consist of O2 consumption for the sarcoplasmic reticulum Ca2+ pump.

Myocardial Ca2+ handling during excitation-contraction coupling has been modelled mathematically to gain a better insight into the expectation that Ca2+ sensitization of contractile machinery may save myocardial energy utilization for Ca2+ handling. The basic model of myocardial Ca2+ kinetics and mechanoenergetics involved the sarcoplasmic reticulum (SR), sarcoplasm, troponin C (Tn) and crossbridges (CB). The relations among the released Ca2+ ions from the SR, peak concentrations of sarcoplasmic free Ca2+ ([Ca2+]i) and Ca(2+)-bound troponin ([TnCa]) and peak contractile force were computed, based upon the assumptions that the released Ca2+ ions diffuse as free Ca2+ in sarcoplasm, bind kinetically with Tn with an association rate constant of k1, dissociate from TnCa with a dissociation rate constant of k2, and are sequestered into the SR with consumption of ATP. TnCa was associated with CB cycling to develop force with a set of given on and off rate constants. The association constant Ka (= k1/k2) of TnCa as an index of Ca2+ sensitivity of Tn was varied 32-fold from 0.25 to 8/microM. Results showed that Ca2+ sensitization from a lower Ka level could most sharply decrease the total Ca2+ release required to develop the same contractile force. Thus, it would reduce the total Ca2+ handling energy that the SR uses to maintain the same contractility.

We have developed transdermally applicable 10% lidocaine aqueous gel containing an absorption promoter and applied it for 15 patients suffering from severe pain in acute or subacute phase of herpes zoster. The patients, consisting of 7 males and 8 females with a mean age 58.5 +/- 13.0 (SD) yrs, had skin eruptions of herpes zoster for the past 2 months. Lidocaine-gel was applied locally to the diseased skin with or without an occlusive dressing. In 14 of the 15 patients (93%), a remarkable reduction of pain (below 10% of pretreatment level) was obtained after 9.9 +/- 5.6 (SD) times of lidocaine-gel treatments. There was no adverse systemic reactions or local skin damages. None of them developed post-herpetic neuralgia. The lidocaine-gel treatment appears to be very useful for reduction of pain associated with acute or subacute phase of herpes zoster.

We previously proposed i) Emax (end-systolic maximum elastance of the ventricle) as an index of contractility independent of preload and afterload and ii) PVA (systolic pressure-volume area of the ventricle) as a measure of the total mechanical energy generated by the ventricular contraction. Emax is defined as the slope of the end-systolic pressure-volume relation, which is relatively linear within the normal working range of the left ventricle. A working pressure-volume point starts from the end-diastolic pressure-volume curve, comes close to or slightly exceeds the end-systolic pressure-volume line, and returns to the end-diastolic curve. Thus, the end-diastolic and end-systolic pressure-volume curves envelop a family of pressure-volume trajectories of variously loaded contractions in a stable contractility. Emax increases with enhanced contractility and decreases with depressed contractility. PVA is an area between the end-diastolic and end-systolic pressure-volume curves on the origin side of the systolic pressure-volume trajectory. PVA linearly correlates with myocardial oxygen consumption regardless of ventricular loading conditions in a given Emax and this load-independent oxygen consumption-PVA relation is elevated with an enhanced Emax. Consequently, Emax and PVA have proved to be key measures and concepts in the physiology of cardiac performance.