1,231 research outputs found
Report of a joint Norwegian-Soviet acoustic survey on blue whiting, spring 1991
During spring 1991 the second Norwegian-Soviet joint survey on the
blue whiting spawning stock was carried out. The result of a ship-to-ship
calibration of the acoustic instruments allowed a 1:1 relationship
between the two vessels acoustic data to be used. According to
this, the data were then combined and presented as common results.
Blue whiting was recorded from south of the Porcupine bank to north of
Shetland, but this year the densest concentrations over the Porcupine
bank were distributed more to the east than previous years.
While the abundance in the southern part of the surveyed area was
approximately the same as estimated the last years, it was found to be
significantly reduced in the north. The over all spawning stock size
was then estimated to 4.4 mill. tonnes which is 1 mill. tonnes less
than observed in 1990. The 1989-yearclass as expected was found to be
the richest one, with a contribution of 23% of the stock.
Although the temperature below 200 m depth in the southern part was in
general higher than in 1990, the maturation process of the blue
whiting gonads was observed to be somewhat retarded with the peak of
spawning 1-2 weeks later than in 1990
Metallic materials for medical use
This article provides a brief overview of the metallic materials used as implants in orthopedics, the alloying system and a complex of the physical-mechanical properties for metallic materials certified for medical use, as well as the advantages and drawbacks of using metallic materials as implants. Approaches to improve the quality of an implant made of metallic materials are noted
Novel Driver Strength Index highlights important cancer genes in TCGA PanCanAtlas patients
Background Cancer driver genes are usually ranked by mutation frequency, which does not necessarily reflect their driver strength. We hypothesize that driver strength is higher for genes preferentially mutated in patients with few driver mutations overall, because these few mutations should be strong enough to initiate cancer. Methods We propose formulas for the Driver Strength Index (DSI) and the Normalized Driver Strength Index (NDSI), the latter independent of gene mutation frequency. We validate them using TCGA PanCanAtlas datasets, established driver prediction algorithms and custom computational pipelines integrating SNA, CNA and aneuploidy driver contributions at the patient-level resolution. Results DSI and especially NDSI provide substantially different gene rankings compared to the frequency approach. E.g., NDSI prioritized members of specific protein families, including G proteins GNAQ, GNA11 and GNAS, isocitrate dehydrogenases IDH1 and IDH2, and fibroblast growth factor receptors FGFR2 and FGFR3. KEGG analysis shows that top NDSI-ranked genes comprise EGFR/FGFR2/GNAQ/GNA11–NRAS/HRAS/KRAS–BRAF pathway, AKT1–MTOR pathway, and TCEB1–VHL–HIF1A pathway. Conclusion Our indices are able to select for driver gene attributes not selected by frequency sorting, potentially for driver strength. Genes and pathways prioritized are likely the strongest contributors to cancer initiation and progression and should become future therapeutic targets
Event-by-event fluctuations in mean p(T) and mean e(T) in root s(NN)=130 GeV Au+Au collisions
Distributions of event-by-event fluctuations of the mean transverse momentum and mean transverse energy near mid-rapidity have been measured in Au+Au collisions at roots(NN)=130 GeV at the Relativistic Heavy-Ion Collider. By comparing the distributions to what is expected for statistically independent particle emission, the magnitude of nonstatistical fluctuations in mean transverse momentum is determined to be consistent with zero. Also, no significant nonrandom fluctuations in mean transverse energy are observed. By constructing a fluctuation model with two event classes that preserve the mean and variance of the semi-inclusive p(T) or e(T) spectra, we exclude a region of fluctuations in root s(NN)=130 GeV Au+Au collisions
Suppression of hadrons with large transverse momentum in central Au+Au collisions at root s(NN)=130 GeV
Transverse momentum spectra for charged hadrons and for neutral pions in the range 1 Gev/c \u3c P - T \u3c 5 GeV/c have been measured by the PHENIX experiment at RHIC in Au + Au collisions at root S(NN) = 130 GeV. At high p(T) the spectra from peripheral nuclear collisions are consistent with scaling the spectra from p + p collisions by the average number of binary nucleon-nucleon collisions. The spectra from central collisions are significantly suppressed when compared to the binary-scaled p + p expectation, and also when compared to similarly binary-scaled peripheral collisions, indicating a novel nuclear-medium effect in central nuclear collisions at RHIC energies
Measurement of single electrons and implications for charm production in Au+Au collisions at root(NN)-N-S=130 GeV
Transverse momentum spectra of electrons from Au+Au collisions at roots(NN) = 130 GeV have been measured at midrapidity by the PHENIX experiment at the Relativistic Heavy Ion Collider. The spectra show an excess above the background from photon conversions and light hadron decays. The electron signal is consistent with that expected from semileptonic decays of charm. The yield of the electron signal dN(e)/dy for p(T) \u3e 0.8 GeV/c is 0.025 +/- 0.004(stat) +/- 0.010( syst) in central collisions, and the corresponding charm cross section is 380 +/- 60(stat) +/- 200(syst ) mu b per binary nucleon-nucleon collision
Transverse-mass dependence of two-pion correlations in Au+Au collisions at root(NN)-N-S=130 GeV
Two-pion correlations in roots(NN) = 130 GeV Au+Au collisions at RHIC have been measured over a broad range of pair transverse momentum k(T) by the PHENIX experiment at RHIC. The k(T) dependent transverse radii are similar to results from heavy-ion collisions at roots(NN) = 4.1 , 4.9, and 17.3 GeV, whereas the longitudinal radius increases monotonically with beam energy. The ratio of the outwards to sidewards transverse radii (R-out/R-side) is consistent with unity and independent of k(T)
Centrality dependence of pi(+/-), K-+/-, p, and (p)over-bar production from root(NN)-N-S = 130 GeV Au+Au collisions at RHIC
Identified pi(+/-), K+/-, p, and (p) over bar transverse momentum spectra at midrapidity in root s(NN) = 130 GeV Au + Au collisions were measured by the PHENIX experiment at RHIC as a function of collision centrality. Average transverse momenta increase with the number of participating nucleons in a similar way for all particle species. Within errors, all midrapidity particle yields per participant are found to be increasing with the number of participating nucleons. There is an indication that K+/-, p, and (p) over bar yields per participant increase faster than the pi(+/-) yields. In central collisions at high transverse momenta (p(T) greater than or similar to 2 GeV/c), (p) over bar and p yields are comparable to the pi(+/-) yields
Net charge fluctuations in Au+Au interactions root s(NN)=130 GeV
Data from Au+Au interactions at s(NN)=130 GeV, obtained with the PHENIX detector at the Relativistic Heavy-Ion Collider, are used to investigate local net charge fluctuations among particles produced near midrapidity. According to recent suggestions, such fluctuations may carry information from the quark-gluon plasma. This analysis shows that the fluctuations are dominated by a stochastic distribution of particles, but are also sensitive to other effects, like global charge conservation and resonance decays
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