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Search Results: 1 - 10 of 1053 matches for " Tomohiro Nakada "
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Computational Study for the Aromatic Nucleophilic Substitution Reaction on 1-Dimethylamino-2,4-bis(trifluoroacetyl)-naphthalene with Amines  [PDF]
Norio Ota, Tomohiro Nakada, Takumi Shintani, Yasuhiro Kamitori, Etsuji Okada
International Journal of Organic Chemistry (IJOC) , 2018, DOI: 10.4236/ijoc.2018.83020
Abstract: Our previous research showed that aliphatic amines were put in order of high reactivity as “ethylamine > ammonia > t-butylamine > diethylamine” on the aromatic nucleophilic substitution of 1-dimetylamino-2,4-bis(trifluoroacetyl)-naphthalene 1 in acetonitrile. The DFT calculation study (B3LYP/6-31G* with solvation model) for the reactions of 1 with above four amines rationally explained the difference of each amines reactivity based on the energies of their Meisenheimer complexes 3 which are assumed to formed as the reaction intermediates in the course of the reaction giving the corresponding N-N exchange products 2. Intramolecular hydrogen bond between amino proton in 1-amino group and carbonyl oxygen in 2-trifluoroacetyl group stabilizes Meisenheimer complexes 3 effectively, and accelerates the substitution reaction from 1 to 2. Our calculation results also predicted that the above order of amines is also true if less polar toluene is used as a solvent instead of acetonitrile even though more enhanced conditions are required.
Muscle endurance measurement using a progressive workload and a constant workload by maximal voluntary contraction  [PDF]
Shinichi Demura, Masakatsu Nakada
Health (Health) , 2010, DOI: 10.4236/health.2010.211186
Abstract: Muscle endurance measurement using a progressive workload method may reduce pain sensation in the subject. This study aimed to examine the relationships between force-time parameters during sustained static gripping as measured by maximal voluntary contraction (MVC) using either a progressive workload (PW) or a constant workload (CW). Sixteen subjects performed sustained static gripping with 7 gradually increasing relative demand values of 20% to 80% MVC and sustained static gripping by MVC. The staging of progressive workload was 10 s for 20% MVC, 20 s each for 30, 40, 50, 60, and 70% MVC, and 10 s for 80% MVC. The forces exerted at 120 s in the CW and PW methods were at around the 23-27% MVC level. Peak force, final force, and force during the last 30 s for the PW method evaluated muscle endurance after 1 min and showed high correlations (r = 0.746 ? 0.895). Significant correlations (r = 0.575 ? 0.605) were found between time to 40% MVC in the CW method and peak force, final force, and force in the last 30 s in the PW method group. The peak force in the PW method may be useful for evaluating muscle endurance with a short testing time and without high pain sensation.
Effect of past and present lifestyle habits and nutrition on calcaneal quantitative osteo-sono index in pre- and post-menopausal females  [PDF]
Masakatsu Nakada, Shinichi Demura
Health (Health) , 2010, DOI: 10.4236/health.2010.22019
Abstract: This study is examined the effect of past and present lifestyle habits and nutrition on the os-teo-sono assessment index (OSI) in pre- and post-menopausal females. The subjects were 200 premenopausal females (38.8±10.3years) and 156 postmenopausal females (59.2±5.9 ye- ars). BMD (Body mineral density) was estimated by right-calcaneal OSI using an ultrasonic transmission method with an AOS-100 device (ALOKA). The number of postmenopau- sal fe-males in the close examination and guidance required groups (80 cases: 51.3 %) (OSI < 2.428) was significantly higher than that of premeno-pausal females (44 cases: 22.0 %) (χ2=33.105: P<0.000). In premenopausal females, the proportion of subjects that had not taken vitamin D in the past (in junior high school and high school) was significantly higher in the close examination- guidance required group (OSI < 2.428) than in the normal group (OSI ≧ 2.428). However, in postmenopausal females, there was no signifi-cant difference in past and present lifestyle habits and nutrition between the close exami-nation-guidance required group and the normal group. In premenopausal females, it was deter-mined that the intake of vitamin D during pu-berty increased the absorption of calcium sig-nificantly.
The effect of past and present lifestyle, nutrition habits, and gender on bone mineral density  [PDF]
Masakatsu Nakada, Shinichi Demura
Health (Health) , 2010, DOI: 10.4236/health.2010.27109
Abstract: This study aimed to examine the gender and age differences of the quantitative osteo-sono assessment index (OSI) and the effects of the past and present lifestyle and nutrition habits on OSI in adult males and females from 20 to 70 years of age. The subjects were 155 males (20- 79 years) and 399 females (20-78 years). The bone mass was estimated by the right-calcaneal OSI using an ultrasonic transmission method with an AOS-100 device (ALOKA). The frequency of tests for OSI in women tended to increase rapidly in the 50-70 age group requiring close examination or guidance. In 50-70 year- old females, the proportion of dairy products and vitamin D intake in the past (junior high school and high school days) was significantly lower in the group requiring close examination or guidance (OSI < 2.428) than in the normal group (OSI ≧ 2.428). That is, there was insufficient calcium intake (through dairy products) and vitamin D intake, which is instrumental in calcium absorption, (through fish, chicken eggs, and fungi) during puberty, when bone mass increases with skeletal growth. In conclusion, the number in the group requiring close examination or guidance was high for 50-70 year-old males and females. The OSI decreases rapidly in females after their 50s and the number in the group requiring close examination or guidance increased rapidly.
The Characteristics and Laterality of Explosive Force Exertion of Hand Grip and Toe Grip  [PDF]
Masakatsu Nakada, Shinichi Demura
Advances in Physical Education (APE) , 2014, DOI: 10.4236/ape.2014.44021
Abstract: This study examines the force exertion characteristics and laterality of maximal explosive force exertion of hand grip and toe grip. Fifteen male subjects, aged 19 to 23 years, performed maximal explosive hand grip and toe grip exertions with their dominant and non-dominant sides. Maximal force value and integral force for 2 sec in the hand grip exertions were significantly larger than those in the toe grip exertions in both the dominant and non-dominant sides. The time required to achieve 90% maximal force value in the hand grip exertions was significantly shorter than that in the toe grip exertions in both sides. Correlations between the dominant and non-dominant sides were significant (r = 0.710 - 0.889) in maximal force value and integral force for 2 sec during the hand and toe grip exertions, but they were not significant (hand grip: r = 0.242, toe grip: r = 0.032) with respect to the time taken to achieve 90% maximal force value. In conclusion, a force exertion value increases more quickly in an explosive hand grip than that in an explosive toe grip. The laterality may relate to time parameters in both explosive force exertions, but not to ones related to force.
Potential for Biomass and Biofuel through Sustainable Intensification of Agriculture and Reduction of Food Losses and Waste  [PDF]
Jeffrey Skeer, Shunichi Nakada
Natural Resources (NR) , 2016, DOI: 10.4236/nr.2016.71002
Abstract: Substantial potential exists to expand supplies of biomass for energy applications through more systematic collection of agricultural residues, more intensive cultivation of croplands, and reduced waste and losses in the food chain. This study aims to show how the potential can be calculated from public information sources, to put the potential in the context of global needs for liquid transport fuels, and to suggest some practical policy options for bringing part of the potential to market. It finds that if the theoretical potential is fully realized, enough liquid biofuel could be produced to displace the equivalent of all current global liquid fuel use for transport.
Contact Urticaria Syndrome from Tofu  [PDF]
Maki Kitakawa, Tokio Nakada
Case Reports in Clinical Medicine (CRCM) , 2016, DOI: 10.4236/crcm.2016.56038
Abstract: A-52-year-old woman ate dinner after preening roses in her garden. Immediately, she developed oralaryngeal malaise and pruritic rash. Nasal obstruction and increase of cutaneous lesions were seen although she took betamethasone, 2 mg, orally. Physical examination revealed geographic wheal on trunk and extremities, and no overt mucosal lesions. History demonstrated that she had developed such reactions four times before: three of the four were seen shortly after eating soybean. Tofu was examined by prick-by-prick testing, and prick testing was performed with a petal, a piece of stem and rose leaf, positive and negative control. Positive reactions to tofu (wheal, 5 × 7 mm) and positive control (wheal 5 × 5 mm) and negative ones to others were noted. Although sensitization to soybean seemed to antedate pollen allergy on the basis of interview, oral allergy syndrome could be complicated because of various pollens-specific IgE. Since soy-bean specific IgE was class 2, such titer was not an effective predictor of clinical severity. This case should be classified into stage 3 of contact urticaria syndrome (CUS). Since CUS can be fatal, we must be careful in management for such patients.
Application of Gaussian expansion method to nuclear mean-field calculations with deformation
H. Nakada
Physics , 2008, DOI: 10.1016/j.nuclphysa.2008.05.011
Abstract: We extensively develop a method of implementing mean-field calculations for deformed nuclei, using the Gaussian expansion method (GEM). This GEM algorithm has the following advantages: (i) it can efficiently describe the energy-dependent asymptotics of the wave functions at large $r$, (ii) it is applicable to various effective interactions including those with finite ranges, and (iii) the basis parameters are insensitive to nuclide, thereby many nuclei in wide mass range can be handled by a single set of bases. Superposing the spherical GEM bases with feasible truncation for the orbital angular momentum of the single-particle bases, we obtain deformed single-particle wave-functions to reasonable precision. We apply the new algorithm to the Hartree-Fock and the Hartree-Fock-Bogolyubov calculations of Mg nuclei with the Gogny interaction, by which neck structure of a deformed neutron halo is suggested for $^{40}$Mg.
Review on CP Violation
Tatsuya Nakada
Physics , 1993, DOI: 10.1063/1.45461
Abstract: A phenomenological description of the neutral K and B meson systems is presented. The situation of the current CP violation experiments is described and a detailed discussion of their results is given, followed by some future prospects.
Review of CP Violation Studies with B-Mesons at LHC
Tatsuya Nakada
Physics , 1995,
Abstract: The Large Hadron Collider (LHC) proposed at CERN will be the ultimate source of B-mesons. With the large number of B-mesons expected at LHC, a real precision test of CP violation in B-meson decays will become possible. There are already several efforts made to explore this possibility and a summary of those activities is presented.
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