OALib Journal期刊

ISSN: 2333-9721



匹配条件: “Akaishi” ,找到相关结果约63条。
Characterizing Interdisciplinarity of Researchers and Research Topics Using Web Search Engines
Hiroki Sayama, Jin Akaishi
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0038747
Abstract: Researchers' networks have been subject to active modeling and analysis. Earlier literature mostly focused on citation or co-authorship networks reconstructed from annotated scientific publication databases, which have several limitations. Recently, general-purpose web search engines have also been utilized to collect information about social networks. Here we reconstructed, using web search engines, a network representing the relatedness of researchers to their peers as well as to various research topics. Relatedness between researchers and research topics was characterized by visibility boost—increase of a researcher's visibility by focusing on a particular topic. It was observed that researchers who had high visibility boosts by the same research topic tended to be close to each other in their network. We calculated correlations between visibility boosts by research topics and researchers' interdisciplinarity at the individual level (diversity of topics related to the researcher) and at the social level (his/her centrality in the researchers' network). We found that visibility boosts by certain research topics were positively correlated with researchers' individual-level interdisciplinarity despite their negative correlations with the general popularity of researchers. It was also found that visibility boosts by network-related topics had positive correlations with researchers' social-level interdisciplinarity. Research topics' correlations with researchers' individual- and social-level interdisciplinarities were found to be nearly independent from each other. These findings suggest that the notion of “interdisciplinarity" of a researcher should be understood as a multi-dimensional concept that should be evaluated using multiple assessment means.
Reaction cross sections of hypernuclei and the shrinkage effect
T. Akaishi,K. Hagino
Physics , 2013, DOI: 10.1103/PhysRevC.88.047603
Abstract: We calculate the reaction cross sections for $^6{\rm Li}$ and $^7_{\Lambda}{\rm Li}$ on a $^{12}{\rm C}$ target at $100\,{\rm MeV/nucleon}$ using the Glauber theory. To this end, we assume a two-body cluster structure for $^6$Li and $^7_{\Lambda}{\rm Li}$, and employ the few-body treatment of the Glauber theory, that is beyond the well known optical limit approximation. We show that the reaction cross section for $^7_{\Lambda}{\rm Li}$ is smaller than that for $^6$Li by about 4\%, reflecting the shrinkage effect of the $\Lambda$ particle.
Enhanced formation of a dense Kbar nuclear cluster K^- pp in pp collisions - Lambda*-p doorway dominance
Toshimitsu Yamazaki,Yoshinori Akaishi
Physics , 2006,
Abstract: We have found theoretically that the elementary process, p + p to K+ + Lambda(1405) + p, which occurs in a short impact parameter (around 0.2 fm) and with a large momentum transfer (Q ~ 1.6 GeV/c), leads to unusually large self-trapping of Lambda(1405) by the projectile proton, when a Lambda* -p system exists as a dense bound state (size ~ 1.0 fm) propagating to K^-pp. The seed, called "Lambda*-p doorway", is expected to play an important role in the (p, K*) type reactions and heavy-ion collisions to produce various Kbar nuclear clusters.
The basic K nuclear cluster K- pp and its enhanced formation in the p + p -> K+ + X reaction
Toshimitsu Yamazaki,Yoshinori Akaishi
Physics , 2007, DOI: 10.1103/PhysRevC.76.045201
Abstract: We have studied the structure of K- pp nuclear cluster comprehensively by solving this three-body system exactly in a variational method starting from the Ansatz that the Lambda(1405) resonance (Lambda*) is a K-p bound state. We have found that our original prediction for the presence of K-pp as a compact bound system with M = 2322$ MeV/c2, B = 48 MeV and Gamma = 60 MeV remains unchanged by varying the Kba-rN and NN interactions widely as far as they reproduce Lambda(1405). The structure of K- pp reveals a molecular feature, namely, the K- in Lambda* as an "atomic center" plays a key role in producing strong covalent bonding with the other proton. We have shown that the elementary process, p + p -> K+ + Lambda* + p, which occurs in a short impact parameter and with a large momentum transfer (Q ~ 1.6$ GeV/c), leads to unusually large self-trapping of Lambda* by the participating proton, since the Lambda*-p system exists as a compact doorway state propagating to K- pp (R{Lambda*-p} ~ 1.67 fm).
Emission spectra and invariant masses of Lambda and p in the stopped-K-NN absorption process in 4He and 6Li
Toshimitsu Yamazaki,Yoshinori Akaishi
Physics , 2006, DOI: 10.1016/j.nuclphysa.2007.05.014
Abstract: We have calculated the emission spectra of Y and N and invariant masses of YN pairs in the direct K-NN --> YN absorption process at rest in 4He and light nuclei in order to provide theoretical tools for correct interpretations of experimental data with or without invoking kaonic nuclear bound states. All the momentum distributions are broad with widths around 150-200 MeV/c (except for the case of 6Li target), while the partial invariant mass of each YN pair has a peak around 2310-2330 MeV/c2. We argue against the interpretations of stopped-K- experimental data of KEK and FINUDA by Oset and Toki and by Magas, Oset, Ramos and Toki.
Super strong nuclear force caused by migrating Kbar mesons - Revival of the Heitler-London-Heisenberg scheme in kaonic nuclear clusters
Toshimitsu Yamazaki,Yoshinori Akaishi
Physics , 2007, DOI: 10.2183/pjab.83.144
Abstract: We have studied the structure of K- pp comprehensively by solving this three-body system in a variational method, starting from the Ansatz that the Lambda(1405) resonance (~ Lambda*) is a K-p bound state. The structure of K-pp reveals a molecular feature, namely, the K- in Lambda* as an "atomic center" plays a key role in producing strong covalent bonding with the other proton. We point out that strongly bound Kbar nuclear systems are formed by ``super strong" nuclear force due to migrating real bosonic particles Kbar a la Heitler-London-Heisenberg, whereas the normal nuclear force is caused by mediating virtual pions. We have shown that the elementary process, p + p --> K+ + Lambda* + p, which occurs in a short impact parameter and with a large momentum transfer, leads to unusually large self-trapping of Lambda* by the involved proton, since the Lambda*-p system exists as a compact doorway state propagating to K-pp.
Isolated proteinuria as an initial sign of severe preeclampsia  [PDF]
Takahiro Yamada, Takashi Yamada, Mamoru Morikawa, Masamitsu Takeda, Ryutaro Nishida, Rina Akaishi, Hisanori Minakami
Open Journal of Obstetrics and Gynecology (OJOG) , 2011, DOI: 10.4236/ojog.2011.12003
Abstract: Two pregnant women who initially developed proteinuria alone followed by serious preeclampsia are presented to emphasize that there is no adequate technical term to express the period of proteinuria alone based on the current criteria of pregnancy-induced hypertension. Case 1 exhibited a urinary protein concentration of 46 mg/dL in the absence of hypertension, and abdominal pain due to placental abruption with hypertension at gestational week (GW) 29–3/7 and 29–4/7, respectively. Case 2 exhibited a urinary protein/creatinine ratio of 2.67, developed hypertension, required cesarean section, and developed posterior reversible encephalopathy syndrome at GW 28–1/7, 29–6/7, and 32–0/7, and on postpartum day 2, respectively. As women with proteinuria alone are not diagnosed as having preeclampsia and as a diagnosis of gestational proteinuria can be made only at 12 weeks postpartum, a prospective technical term applicable to the condition of proteinuria alone is needed to increase physicians’ attention to this condition.
Avalia??o do desempenho da tecnologia NeoSoniX TM em cirurgias de catarata
Akaishi, Leonardo;Silva, Rodrigo Vaz de Queiroz;
Arquivos Brasileiros de Oftalmologia , 2006, DOI: 10.1590/S0004-27492006000300019
Abstract: purpose: the techniques and results of cataract surgery have improved dramatically with technological advancements. one of the reasons for this improvement would be the reduced use of ultrasound with the new phacoemulsification devices. the objective of this study is to confirm the theoretical advantage of the neosonix handpiece. methods: the authors compared the results of the parameters recorded by the legacy phacoemulsification system during 300 cataract surgeries performed with the use of the conventional ultrasound handpiece and 100 performed with the innovative neosonixtm. all surgeries were performed by the same senior surgeon, using the same surgical technique. the choice of handpiece was random. the handpieces were compared considering cataract grade of hardness, in relation to parameters of ultrasound time, amount of balanced saline solution, and percentage of average power used during surgery. results: the analysis performed retrospectively on a chronological series of cases showed that the time of ultrasound used with the neosonix handpiece was inferior to that with the conventional handpiece, for any cataract grade of hardness (p<0.000001). the volume of balanced saline solution used during surgical procedures was smaller, favoring the neosonix technology (p<0.000001). in relation to the percentage of ultrasound energy used with the different technologies, an inferior value was found in the group who underwent surgery with the use of the neosonix handpiece (p<0.000001). conclusions: based on the information provided by these surgeries, we may claim that there was a significant superiority when using the neosonix handpiece in comparison to the conventional legacy machine handpiece in cataract surgeries, regardless of cataract grade.
The investigation of Λ(1405) state in the stopped K reaction on deuterium
Suzuki T.,Esmaili J.,Akaishi Y.
EPJ Web of Conferences , 2010, DOI: 10.1051/epjconf/20100307014
Abstract: Nowadays, extensive studies of the problem of the deeply bound $ar{K}$ nuclei stimulate the reconsid eration of Λ(1405) state as the theoretical basis of the binding of $ar{K}$ nuclei, and the old question of the nature of Λ(1405) becomes a modern subject by the new interest. In contrast to one of conventional interpretations of Λ(1405) as the $ar{K}$N quasi-bound state at 1405 MeV/c2 , a two-pole hypothesis, by which Λ(1405) consists of two poles at 1420 and 1390 MeV/c2 couple mainly with $ar{K}$N and Σπ channels, respectively, was proposed recently. On the other hand, a very recent theoretical analysis has clari ed that the (Σπ)0 invariant mass spectra after K absorption in d re ect strikingly resonant formation of Λ(1405) (or Λ(1420)) and thus are capable of distinguishing di erent Ansatz’s. We have proposed a new experiment by means of the stopped K reaction on liquid deuterium at J-PARC K1.8BR beamline with E15/E17 experimental devices, so as to give a new precision- and high-statistics-data of (Σπ)0 mass spectra to examine the issue, Λ(1405) or Λ(1420), in the most reliable way, and thus to answer the most fundamental questions of $ar{K}$N interaction and $ar{K}$ nuclei.
Hidden renal disease in a female patient with long-lasting isolated gestational proteinuria followed by hypertension  [PDF]
Kosuke Kawabata, Rina Akaishi, Ayako Nozaki, Osamu Sato, Kaoru Hanatani, Hisanori Minakami
Open Journal of Obstetrics and Gynecology (OJOG) , 2013, DOI: 10.4236/ojog.2013.39124

Background: The prevalence of asymptomatic renal scarring, such as a focal segmental glomerulosclerosis (FSGS), was suggested to be high in women who develop preeclampsia. FSGS is a risk factor for endstage renal disease. Objective: To document preeclamptic women with proteinuria that developed eight weeks prior to hypertension with confirmed FSGS postpartum. Case: A 20-year-old nulliparous Japanese woman with a negative dipstick test result at gestational week (GW) 18 exhibited proteinuria 1+ on dipstick test at GW 22. Proteinuria determined from the random urine protein to creatinine ratio (P/Cr, g/g) was increased from 3.7 at GW 26 to 4.6 and 8.9 at GW 28 and 30, respectively. She developed hypertension (142/66 mmHg) at GW 30. Due to increased edema, emergency cesarean section was performed at GW 33. She gave birth to an otherwise healthy female small-for-gestational-age infant, weighing 1290 g. Postpartum course was uneventful except for persisting proteinuria: P/Cr of 9.8 just before delivery decreased to 3.6 and 1.7 on postpartum weeks 9 and 17, respectively. Renal biopsy on postpartum week 13 revealed FSGS in this patient. Conclusion: Hidden FSGS may have manifested as preeclampsia in this patient. This case highlighted the need to determine the prevalence of asymptomatic FSGS among women who later develop preeclampsia.


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