671 research outputs found
Fingerprinting models of first-order phase transitions by the synergy between collider and gravitational-wave experiments
We investigate the sensitivity of future space-based interferometers such as
LISA and DECIGO to the parameters of new particle physics models which drive a
first-order phase transition in the early Universe. We first perform a Fisher
matrix analysis on the quantities characterizing the gravitational wave
spectrum resulting from the phase transition, such as the peak frequency and
amplitude. We next perform a Fisher analysis for the quantities which determine
the properties of the phase transition, such as the latent heat and the time
dependence of the bubble nucleation rate. Since these quantities are determined
by the model parameters of the new physics, we can estimate the expected
sensitivities to such parameters. We illustrate this point by taking three new
physics models for example: (1) models with additional isospin singlet scalars
(2) a model with an extra real Higgs singlet, and (3) a classically conformal
model. We find that future gravitational wave observations play
complementary roles to future collider experiments in pinning down the
parameters of new physics models driving a first-order phase transition.Comment: 64 pages, 35 figure
Boron and chlorine abundances in Antarctic chondrites: A PGA study
Boron and chlorine abundances were determined by prompt gamma-ray analysis for Antarctic meteorites of 22 carbonaceous chondrites and 12 ordinary chondrites. Both B and Cl contents of most Antarctic meteorites analyzed in this study are systematically higher than those for non-Antarctic chondrites of corresponding groups, implying that Antarctic meteorites of carbonaceous and ordinary chondrite groups were contaminated with not only Cl (and other halogens like I) but also B. Boron and Cl contents are correlated with each other in Antarctic ordinary chondrites whereas no apparent correlation can be seen for carbonaceous chondrites. Considering that interior portions were used for carbonaceous chondrites while interior and outer portions were randomly sampled for ordinary chondrite used in this study, B and Cl are distributed differently between the two groups of chondrite, suggesting that B and Cl independently behaved following their own chemical properties after contaminant(s) carrying these elements adhered on the surface of meteorites. Sea mist is a probable candidate for such a contaminant. Leaching experiments showed that no B is essentially recovered by water and acetone even from pulverized specimens, from which a fairly large fraction of Cl is recovered, confirming that B and Cl reside independently in chondrite samples and further that both elements behaved differently after sticking to these samples on Antarctica
Collaboration Research of Tohoku University, Universitas Pendidikan Indonesia and Shirayuri Women’s College Global Study of Student Engagement
Anodal Transcranial Direct Current Stimulation Induces High Gamma-Band Activity in the Left Dorsolateral Prefrontal Cortex During a Working Memory Task: A Double-Blind, Randomized, Crossover Study
Transcranial direct current stimulation (tDCS) has been shown to have mixed effects on working memory (WM) capacity in healthy individuals. Different stimulation paradigms may account for these discrepancies, with certain features being favored. To determine the effect in the context of anodal tDCS, we investigated whether anodal tDCS induced cortical oscillatory changes during a WM task. Specifically, we tested whether anodal offline tDCS over the left prefrontal cortex (PFC) enhances WM capacity by modulating the oscillatory activity in the left dorsolateral PFC (DLPFC) using magnetoencephalography (MEG). This study employed a double-blind, randomized, crossover design, in which 24 healthy right-handed participants conducted MEG recordings during a 3-back task after administration of 2 mA tDCS or sham stimulation as a placebo. Our results showed that the effect of tDCS did not appear in the behavioral indices—WM accuracy (d′) or reaction time (RT). From the results of the time-frequency analysis, significant event-related synchronization (ERS) in the high-gamma band (82–84 Hz) of the left DLPFC was found under the tDCS condition; however, ERS was not correlated with WM capacity. Furthermore, we calculated the modulation index (MI), which indicates the strength of phase-amplitude coupling (PAC). tDCS significantly decreased MI of the left DLPFC, representing the theta-gamma PAC during the n-back task using color names as verbal stimuli. Our results suggest that although tDCS increased the gamma-band oscillation indicating greater neural activity in the left DLPFC, it did not lead to an improvement of WM capacity; this may be due to the inability of gamma-band oscillation to couple with the task-induced theta wave. WM capacity might not increase unless theta-gamma PAC is not enhanced by tDCS
A Novel Compound Heterozygous Mutation in the CYP4V2 Gene in a Japanese Patient with Bietti's Crystalline Corneoretinal Dystrophy
Purpose: To describe the clinical and genetic characteristics of a Japanese family in which one member exhibited Bietti's crystalline corneoretinal dystrophy (BCD). Methods: Using direct sequencing, mutation screening was performed in the CYP4V2 gene of both the patient with BCD and her daughter. Ophthalmic examinations were performed to determine the clinical features of both subjects. Results: The 64-year-old female patient had a bilateral visual acuity of 0.4. Slit lamp examination revealed bilateral crystalline-like deposits at the superior limbus of the cornea. Fundus examination revealed there was chorioretinal atrophy along with numerous glistening yellowish-white crystalline deposits that were scattered throughout the posterior pole and the mid-peripheral retina. Standard flash electroretinography showed an extinguished electroretinogram and Goldmann kinetic perimetry detected a relative scotoma. Genetic analysis revealed that the patient had a heterozygous mutation in the CYP4V2 gene (IVS6-8delTCATACAGGTCATCGCG/GC), which is the most commonly found mutation in Japanese patients with BCD. Furthermore, the patient was also shown to have a novel heterozygous point mutation in exon 9 of the CYP4V2 gene (c.1168C>T). In contrast, her daughter exhibited no clinical findings for BCD even though she carried the same heterozygous mutation in the CYP4V2 gene (c.1168C>T). Conclusion: A novel compound heterozygous mutation was found in the CYP4V2 gene of a patient with BCD. This previously unreported c.1168C>T mutation causes a missense mutation (p.R390C) in the CYP4V2 protein
The announcement effects of a change in the Bank of Japan’s ETF purchase program: An event study
Counting Points for Hyperelliptic Curves of type over Finite Prime Fields
Counting rational points on Jacobian varieties of hyperelliptic curves
over finite fields is very important for constructing
hyperelliptic curve cryptosystems (HCC),
but known algorithms for general curves over given large prime
fields need very long running times.
In this article, we propose an extremely fast point counting algorithm for
hyperelliptic curves of type over given large
prime fields \Fp, e.g. 80-bit fields.
For these curves, we also determine the necessary condition
to be suitable for HCC, that is, to satisfy that the order
of the Jacobian group is of the form where
is a prime number greater than about and
is a very small integer.
We show some examples of suitable curves for HCC obtained by
using our algorithm.
We also treat curves of type where is not
square in \Fp
Suitable Curves for Genus-4 HCC over Prime Fields: Point Counting Formulae for Hyperelliptic Curves of type
Computing the order of the Jacobian group of a hyperelliptic curve
over a finite field is very important to construct
a hyperelliptic curve cryptosystem (HCC), because
to construct secure HCC, we need Jacobian groups of order in the form
l(J\(Bcdot c where is a prime greater than about and
is a very small integer.
But even in the case of genus two,
known algorithms to compute the order of a Jacobian group for a general curve
need a very long running time over a large prime field.
In the case of genus three, only a few examples of suitable curves for HCC are known.
In the case of genus four, no example has been known over a large prime field.
In this article, we give explicit formulae of the order of Jacobian groups for
hyperelliptic curves over a finite prime field of type ,
which allows us to search suitable
curves for HCC. By using these formulae,
we can find many suitable curves for genus-4 HCC and show some examples
Pd-catalyzed Cyclization of Terminal Alkynes using Diazonaphthoquinones: Synthesis of Naphtho[1,2-b]furans
Naphtho[1,2-b] furans were synthesized via a Pd-catalyzed reaction of diazonaphthoquinones and terminal alkynes in the presence of CuI and diisopropylamine. This method was then successfully applied to the synthesis of natural product, furomollugin
Comparability of Weighed Dietary Records and a Self-Administered Diet History Questionnaire for Estimating Monetary Cost of Dietary Energy
An increasing number of studies have estimated monetary diet cost using various dietary assessment methods, based on databases on retail food prices, for investigating its association with dietary intake and health outcomes. However, information regarding the comparability of monetary diet cost across dietary assessment methods is absolutely lacking. This study compared monetary cost of dietary energy estimated from weighed dietary records (DRs) with that estimated from a self-administered diet history questionnaire (DHQ). The subjects were 92 Japanese women aged 31–69 years and 92 Japanese men aged 32–76 years. The DHQ (assessing diet during the preceding month) and 4-day DRs (one weekend day and three weekdays) were completed in each season over a 1-year period (DHQs1-4 and DRs1-4, respectively). An additional DHQ was completed at one year after completing DHQ1 (DHQ5). Monetary cost of dietary energy (Japanese yen/4184 kJ) was calculated using food intake information derived from each dietary assessment method, based on retail food prices. Pearson correlation between the mean of DRs1-4 and mean of DHQs1-4 was 0.64 for women and 0.69 for men. Pearson correlation between the mean of DRs1-4 and DHQ1 was 0.60 for women and 0.52 for men, while intraclass correlation between DHQ1 and DHQ5 was 0.64 for women and 0.51 for men. These data indicate reasonable comparability of monetary cost of dietary energy across DR and a DHQ as well as usefulness of a single administration of the DHQ for estimating monetary cost of dietary energy
- …