29 research outputs found
Local SiC photoluminescence evidence of non-mutualistic hot spot formation and sub-THz coherent emission from a rectangular BiSrCaCuO mesa
From the photoluminescence of SiC microcrystals uniformly covering a
rectangular mesa of the high transition temperature superconductor
BiSrCaCuO, the local surface temperature
was directly measured during simultaneous sub-THz emission from the
intrinsic Josephson junctions (IJJs) in the mesa. At high bias currents and
low bath temperatures K, the center of a large
elliptical hot spot with jumps dramatically with little
current-voltage characteristic changes. The hot spot doesn't alter the
ubiquitous primary and secondary emission conditions: the ac Josephson relation
and the electromagnetic cavity resonance excitation, respectively. Since the
intense sub-THz emission was observed for high K in
the low bias regime where hot spots are absent, hot spots can not provide
the primary mechanisms for increasing the output power, the tunability, or for
promoting the synchronization of the IJJs for the sub-THz emission, but can
at best coexist non-mutualistically with the emission. No standing
waves were observed
Local SiC photoluminescence evidence of hot spot formation and sub-THz coherent emission from a rectangular Bi2Sr2CaCu2O8+delta mesa
From the photoluminescence of SiC microcrystals uniformly covering a rectangular mesa of the high transition temperature T-c superconductor Bi2Sr2CaCu2O8+delta, the local surface temperature T(r) was directly measured during simultaneous sub-THz emission from the N similar to 10(3) intrinsic Josephson junctions (IJJs) in the mesa. At high bias currents I and low bath temperatures T-bath less than or similar to 35 K, the center of a large elliptical hot spot with T(r) \u3e T-c jumps dramatically with little current-voltage characteristic changes. The hot spot does not alter the ubiquitous primary and secondary emission conditions: the ac-Josephson relation and the electromagnetic cavity resonance excitation, respectively. Since the most intense sub-THz emission was observed for high T-bath greater than or similar to 50 K in the low I bias regime where hot spots are absent, hot spots cannot provide the primary mechanisms for increasing the output power, the tunability, or promoting the synchronization of the N IJJs for the sub-THz emission, but can at best coexist nonmutualistically with the emission. No T(r) standing waves were observed
Participatory art activities increase aalivary oxytocin secretion of ASD children
Autism spectrum disorder (ASD) occurs in 1 in 160 children worldwide. Individuals with ASD tend to be unique in the way that they comprehend themselves and others, as well as in the way that they interact and socialize, which can lead to challenges with social adaptation. There is currently no medication to improve the social deficit of children with ASD, and consequently, behavioral and complementary/alternative intervention plays an important role. In the present pilot study, we focused on the neuroendocrinological response to participatory art activities, which are known to have a positive effect on emotion, self-expression, sociability, and physical wellbeing. We collected saliva from 12 children with ASD and eight typically developed (TD) children before and after a visual art-based participatory art workshop to measure the levels of oxytocin, a neuropeptide involved in a wide range of social behaviors. We demonstrated that the rate of increase in salivary oxytocin following art activities in ASD children was significantly higher than that in TD children. In contrast, the change rate of salivary cortisol after participatory art activities was similar between the two groups. These results suggest that the beneficial effects of participatory art activities may be partially mediated by oxytocin release, and may have therapeutic potential for disorders involving social dysfunction
Cavity mode enhancement of terahertz emission from equilateral triangular microstrip antennas of the high-Tcsuperconductor Bi2Sr2CaCu2O8 +δ
We study the transverse magnetic (TM) electromagnetic cavity mode wave functions for an ideal equilateral triangular microstrip antenna (MSA) exhibiting C3v point group symmetry. When the C3v operations are imposed upon the antenna, the TM(m,n) modes with wave vectors are much less dense than commonly thought. The R3 operations restrict the integral n and m to satisfy , where and for the modes even and odd under reflections about the three mirror planes, respectively. We calculate the forms of representative wave functions and the angular dependence of the output power when these modes are excited by the uniform and non-uniform ac Josephson current sources in thin, ideally equilateral triangular MSAs employing the intrinsic Josephson junctions in the high transition temperature Tc superconductor Bi2Sr2CaCu2 , and fit the emissions data from an earlier sample for which the C3v symmetry was apparently broken
Generation of electromagnetic waves from 0.3 to 1.6 terahertz with a high-T-c superconducting Bi2Sr2CaCu2O8+delta intrinsic Josephson junction emitter
To obtain higher power P and frequency f emissions from the intrinsic Josephson junctions in a high-T-c superconducting Bi2Sr2CaCu2O8+delta single crystal, we embedded a rectangular stand-alone mesa of that material in a sandwich structure to allow for efficient heat exhaust. By varying the current-voltage (I-V) bias conditions and the bath temperature T-b, f is tunable from 0.3 to 1.6 THz. The maximum P of a few tens of mu W, an order of magnitude greater than from previous devices, was found at T-b similar to 55K on an inner I-V branch at the TM(1,0) cavity resonance mode frequency. The highest f of 1.6 THz was found at T-b = 10K on an inner I-V branch, but away from cavity resonance frequencies. A possible explanation is presented
Complete Genomic Structure of the Bloom-forming Toxic Cyanobacterium Microcystis aeruginosa NIES-843
The nucleotide sequence of the complete genome of a cyanobacterium, Microcystis aeruginosa NIES-843, was determined. The genome of M. aeruginosa is a single, circular chromosome of 5 842 795 base pairs (bp) in length, with an average GC content of 42.3%. The chromosome comprises 6312 putative protein-encoding genes, two sets of rRNA genes, 42 tRNA genes representing 41 tRNA species, and genes for tmRNA, the B subunit of RNase P, SRP RNA, and 6Sa RNA. Forty-five percent of the putative protein-encoding sequences showed sequence similarity to genes of known function, 32% were similar to hypothetical genes, and the remaining 23% had no apparent similarity to reported genes. A total of 688 kb of the genome, equivalent to 11.8% of the entire genome, were composed of both insertion sequences and miniature inverted-repeat transposable elements. This is indicative of a plasticity of the M. aeruginosa genome, through a mechanism that involves homologous recombination mediated by repetitive DNA elements. In addition to known gene clusters related to the synthesis of microcystin and cyanopeptolin, novel gene clusters that may be involved in the synthesis and modification of toxic small polypeptides were identified. Compared with other cyanobacteria, a relatively small number of genes for two component systems and a large number of genes for restriction-modification systems were notable characteristics of the M. aeruginosa genome
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Electrical Potential Distribution In Terahertz-Emitting Rectangular Mesa Devices Of High- T C Superconducting Bi2Sr2Cacu2O8 + Δ
Excessive Joule heating of conventional rectangular mesa devices of the high-transitiontemperature Tc superconductor Bi2Sr2CaCu2O8 + δ leads to hot spots, in which the local temperature T (r) \u3e Tc. Similar devices without hot spots are known to obey the ac-Josephson relation, emitting sub-terahertz (THz) waves at frequencies f ∝ V N, where V is the applied dc voltage or electrostatic potential and N is the number of active junctions in the device. However, it often has been difficult to predict the emission f from the applied V for two reasons: N is generally unknown and therefore has been assumed to be a fitting parameter, and especially when hot spots are present, V could develop a spatial dependence that cannot be accurately determined using two-terminal measurements. To clarify the situation, simultaneous SiC microcrystalline photoluminescence measurements of T (r), Fourier-transform infrared (FTIR) measurements of f, and both two and four-terminal measurements of the local V (r) were performed. The present four-probe measurements provide strong evidence that when a constant V is measured within the device?s superconducting region outside of the hot spot, the only requirement for the accuracy of the ac-Josephson relation is the ubiquitous adjustment of the fitting parameter N. The four-probe measurements demonstrate that the electric potential distribution is strongly non-uniform near to the hot spot, but is essentially uniform sufficiently far from it. As expected, the emission frequency follows the ac-Josephson relation correctly even for low bath temperatures at which the system jumps to inner IV characteristic branches with smaller N values, reconfirming the ac-Josephson effect as the primary mechanism for the sub- THz emission
Infant Stimulation Induced a Rapid Increase in Maternal Salivary Oxytocin
Oxytocin (OT) is a neuropeptide involved in human social behaviors and reproduction. Non-invasive OT levels in saliva have recently roused interest as it does not require a specialized medical setting. Here, we observed one woman’s basal serum and saliva OT from pregnancy to 1 year postpartum to track OT concentration changes over this period. We examined the changes in salivary OT levels over time in response to maternal physiological and behavioral responses. The fluctuation of saliva OT levels is well correlated with serum OT during pregnancy and breastfeeding. However, while salivary OT increased rapidly during direct interaction (social interaction tests) with the infant and/or when the mother was watching her own infant’s video (video tests), no increase was observed in serum. We used social interaction and video tests on a group of mothers (nine mothers for social interaction and six for the video test) to clarify these single-subject results. In both tests, the mothers had increased OT in their saliva but not serum. Our study may suggest that salivary samples reflect not only the physical but also the emotional state and that saliva samples may be useful for monitoring women’s OT levels during pre- and postpartum periods. Further studies with larger sample numbers are necessary to confirm the rapid changes in salivary OT levels in response to maternal physiological and behavioral responses
Genome-wide Identification of Tebufenozide Resistant Genes in the smaller tea tortrix, Adoxophyes honmai (Lepidoptera: Tortricidae)
The smaller tea tortrix, Adoxophyes honmai, has developed strong resistance to tebufenozide, a diacylhydrazine-type (DAH) insecticide. Here, we investigated its mechanism by identifying genes responsible for the tebufenozide resistance using various next generation sequencing techniques. First, double-digest restriction site-associated DNA sequencing (ddRAD-seq) identified two candidate loci. Then, synteny analyses using A. honmai draft genome sequences revealed that one locus contained the ecdysone receptor gene (EcR) and the other multiple CYP9A subfamily P450 genes. RNA-seq and direct sequencing of EcR cDNAs found a single nucleotide polymorphism (SNP), which was tightly linked to tebufenozide resistance and generated an amino acid substitution in the ligand-binding domain. The binding affinity to tebufenozide was about 4 times lower in in vitro translated EcR of the resistant strain than in the susceptible strain. RNA-seq analyses identified commonly up-regulated genes in resistant strains, including CYP9A and choline/carboxylesterase (CCE) genes. RT-qPCR analysis and bioassays showed that the expression levels of several CYP9A and CCE genes were moderately correlated with tebufenozide resistance. Collectively, these results suggest that the reduced binding affinity of EcR is the main factor and the enhanced detoxification activity by some CYP9As and CCEs plays a supplementary role in tebufenozide resistance in A. honmai