Phytoplakton and Zooplankton Standing Stocks and Downward Flux of Particulate Material around Fast Ice Edge of Lutzow-Holm Bay,Antarctica

Phyto- and zooplankton standing stocks in the fast ice and in the water column under the ice and downward flux of particulate material through the water column were investigated in Liitzow-Holm Bay, Antarctica, during the austral summers, i.e., in January 1977 and February 1979. Chlorophyll a standing stock integrated through the ice was 0.38-0.80 mg/m^2 and that in the water column beneath the ice down to 150 m was 3.06 mg/m^2. Microdistribution of zooplankton beneath the ice was observed by the pumping collections and the dense populations were found just beneath the ice. Zooplankton density was in a range of 12-60 indiv/m^3 and the zooplankton stocks integrated through the 150 m water column ranged from 6000 to 7675 indiv/m^2. By the sediment trap operation, the fecal materials were found to comprise a large proportion of the collected particles. The maximum daily vertical flux of particulate organic carbon (POC) was found at the 100m depth (103 mg C/m^2/day) and concentration of POC in the water column was in a range of 24-56 mg C/m^3. These data on standing stocks of phyto- and zooplankton and vertical flux of POC in the icecovered Liitzow-Holm Bay were compared with those in the other sea areas

QKD from a microsatellite: the SOTA experience

The transmission and reception of polarized quantum-limited signals from space is of capital interest for a variety of fundamental-physics experiments and quantum-communication protocols. Specifically, Quantum Key Distribution (QKD) deals with the problem of distributing unconditionally-secure cryptographic keys between two parties. Enabling this technology from space is a critical step for developing a truly-secure global communication network. The National Institute of Information and Communications Technology (NICT, Japan) performed the first successful measurement on the ground of a quantum-limited signal from a satellite in experiments carried out on early August in 2016. The SOTA (Small Optical TrAnsponder) lasercom terminal onboard the LEO satellite SOCRATES (Space Optical Communications Research Advanced Technology Satellite) was utilized for this purpose. Two non-orthogonally polarized signals in the ~800-nm band and modulated at 10 MHz were transmitted by SOTA and received in the single-photon regime by using a 1-m Cassegrain telescope on a ground station located in an urban area of Tokyo (Japan). In these experiments, after compensating the Doppler effect induced by the fast motion of the satellite, a QKD-enabling QBER (Quantum Bit Error Rate) below 5% was measured with estimated key rates in the order of several Kbit/s, proving the feasibility of quantum communications in a real scenario from space for the first time.Comment: 10 pages, 14 figure

p53 gene mutation analysis in porokeratosis and porokeratosis-associated squamous cell carcinoma

In this and previous studies, we have shown p53 overexpression immunohistochemically in 14 of 17 porokeratotic specimens obtained from 14 lesions of nine cases, and in all six specimens of squamous cell carcinoma (SCC) arising on porokeratotic lesions of two cases. We screened mutations in exons 5 to 10 of the p53 gene in all these specimens by polymerase chain reaction-single strand conformation polymorphism analysis. Mutations of the p53 gene were detected in two of the six SCCs but not in any of the 17 porokeratotic specimens. These two mutations were C to T transitions at codons 146 and 175 in exon 5, which were a nonsense mutation at a dipyrimidine site and a missense mutation at a CG site, respectively. To our knowledge, neither of these mutations has been identified in skin cancers before. Our observations indicate that mutations of the p53 gene are not the major molecular etiology for porokeratosis, but are related to its skin carcinogenesis, and that p53 overexpression in porokeratosis is not due to p53 gene mutations

Association of a single nucleotide polymorphism in titin gene with marbling in Japanese Black beef cattle

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Association of a single nucleotide polymorphism in akirin 2 gene with marbling in Japanese Black beef cattle

Background: Marbling defined by the amount and distribution of intramuscular fat, so-called Shimofuri, is an economically important trait of beef cattle in Japan. The c17-25 expressed sequence tag (EST) has been previously shown to possess expression difference in musculus longissimus muscle between low-marbled and high-marbled steer groups, and to be located within genomic region of a quantitative trait locus for marbling. Thus, the akirin 2 (AKIRIN2) gene containing the c17-25 EST sequence was considered as a positional functional candidate for the gene responsible for marbling. In this study, we explored single nucleotide polymorphism (SNP) in the AKIRIN2 and analyzed association of the SNP with marbling. Findings: A SNP in the 3' untranslated region of the AKIRIN2, referred to as c.*188G>A, was the only difference detected between high- and low-marbled steer groups. The SNP was associated with marbling in 3 experiments using 100 sires (P = 0.041), 753 paternal half-sib progeny steers from 4 sires heterozygous for the c.*188G>A (P = 0.005), and 730 paternal half-sib progeny steers from 3 sires homozygous for the A allele at the c.*188G>A (P = 0.047), in Japanese Black beef cattle. The effect of genotypes of the SNP on subcutaneous fat thickness was not statistically significant (P > 0.05). Conclusion: These findings suggest that the AKIRIN2 SNP polymorphism is associated with marbling and may be useful for effective marker-assisted selection to increase the levels of marbling in Japanese Black beef cattle