359 research outputs found
Coherent Dark States of Rubidium 87 in a Buffer Gas using Pulsed Laser Light
The coherent dark resonance between the hyperfine levels F=1, m=0 and F=2,
m=0 of the rubidium ground state has been observed experimentally with the
light of a pulsed mode-locked diode laser operating at the D1 transition
frequency. The resonance occurs whenever the pulse repetition frequency matches
an integer fraction of the rubidium 87 ground state hyperfine splitting of 6.8
GHz. Spectra have been taken by varying the pulse repetition frequency. Using
cells with argon as a buffer gas a linewidth as narrow as 149 Hz was obtained.
The rubidium ground state decoherence cross section 1.1*10^(-18) cm^2 for
collisions with xenon atoms has been measured for the first time with this
method using a pure isotope rubidium vapor cell and xenon as a buffer gas.Comment: 3 pages, 5 figures, 1 misprint correcte
Applicability of the low-temperature ignition method for determining carbon in various alkali metals
Applicability of low temperature ignition method for determining carbon in alkali metal
Π€ΡΠ°Π·Π΅ΠΎΠ»ΠΎΠ³ΠΈΠ·ΠΌ ΠΊΠ°ΠΊ ΠΎΡΠΎΠ±ΡΠΉ ΡΠΈΠΏ ΡΠ΅ΡΠΌΠΈΠ½ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠΉ Π½ΠΎΠΌΠΈΠ½Π°ΡΠΈΠΈ
ΠΠ½Π°Π»ΠΈΠ·ΠΈΡΡΠ΅ΡΡΡ ΠΊΠΎΠ³Π½ΠΈΡΠΈΠ²Π½Π°Ρ ΡΠΏΠ΅ΡΠΈΡΠΈΠΊΠ° ΡΡΠ°Π·Π΅ΠΎΠ»ΠΎΠ³ΠΈΠ·ΠΌΠΎΠ² Π² ΡΡΠ΅ΡΠ΅ ΡΠ΅ΡΠΌΠΈΠ½ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠΉ Π½ΠΎΠΌΠΈΠ½Π°ΡΠΈΠΈ, Π²ΡΡΠ²Π»ΡΠ΅ΡΡΡ ΡΠΎΠΎΡΠ½ΠΎΡΠ΅Π½ΠΈΠ΅ Π΄Π°Π½Π½ΡΡ
Π΅Π΄ΠΈΠ½ΠΈΡ Ρ ΡΠ°Π·Π»ΠΈΡΠ½ΡΠΌΠΈ ΡΠΈΠΏΠ°ΠΌΠΈ Π·Π½Π°Π½ΠΈΡ. ΠΡΠΎΠ±ΠΎΠ΅ Π²Π½ΠΈΠΌΠ°Π½ΠΈΠ΅ ΡΠ΄Π΅Π»ΡΠ΅ΡΡΡ ΠΏΡΠΈΡΠΈΠ½Π°ΠΌ ΠΈ ΡΠ°ΠΊΡΠΎΡΠ°ΠΌ Π²ΡΠ±ΠΎΡΠ° ΡΡΠ°Π·Π΅ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠΉ Π½ΠΎΠΌΠΈΠ½Π°ΡΠΈΠΈ ΠΏΡΠΈ ΠΏΠ΅ΡΠ΅Π΄Π°ΡΠ΅ ΡΠΏΠ΅ΡΠΈΠ°Π»ΡΠ½ΠΎΠ³ΠΎ Π·Π½Π°Π½ΠΈΡ. ΠΠ²ΡΠΎΡ ΡΡΠ°ΡΡΠΈ ΡΡΠ²Π΅ΡΠΆΠ΄Π°Π΅Ρ, ΡΡΠΎ ΡΠ΅ΡΠΌΠΈΠ½-ΡΡΠ°Π·Π΅ΠΎΠ»ΠΎΠ³ΠΈΠ·ΠΌ Π²Π΅ΡΠ±Π°Π»ΠΈΠ·ΡΠ΅Ρ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ½ΡΡ ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΡ ΠΎ Π²Π½Π΅ΠΏΠΎΠ»ΠΎΠΆΠ΅Π½Π½ΠΎΠΌ ΠΏΡΠΎΡΠ΅ΡΡΠΈΠΎΠ½Π°Π»ΡΠ½ΠΎΠΌ ΠΎΠ±ΡΠ΅ΠΊΡΠ΅, Π²ΠΎΡΠΏΡΠΈΠ½ΡΡΠΎΠΌ Π½ΠΎΠΌΠΈΠ½Π°ΡΠΎΡΠΎΠΌ Π² Π΅Π³ΠΎ Π½Π΅ΡΠ°ΡΡΠ»Π΅Π½Π΅Π½Π½ΠΎΠΉ ΡΠ΅Π»ΠΎΡΡΠ½ΠΎΡΡΠΈ.The article examines the cognitive nature of phraseologisms in terminological nomination, reveals correlation of these units with different types of knowledge. Special attention is paid to the reasons and factors of choosing of phraseological nomination when transmitting special knowledge. The author of the article claims that the term-phraseologism verbalizes comprehensive information about outer professional object, perceived by the nominator in its nonsegmented integrity
A paradigm for controlling virtual humans in urban environment simulations
Presents a new architecture for simulating virtual humans in complex urban environments. The approach is based on the integration of six modules. Four key modules are used in order to manage environmental data, simulate human crowds, control interactions between virtual humans and objects, and generate tasks based on a rule-based behavioral model. The communication between these modules is made through a client/server system. Finally, all low-level virtual human actions are delegated to a single motion and behavioral control module. Our architecture combines various human and object simulation aspects, based on the coherent extraction and classification of information from a virtual city database. This architecture is discussed in this paper, together with a detailed case study exampl
Homozygous Deletion of Six Olfactory Receptor Genes in a Subset of Individuals with Beta-Thalassemia
Progress in the functional studies of human olfactory receptors has been largely hampered by the lack of a reliable experimental model system. Although transgenic approaches in mice could characterize the function of individual olfactory receptors, the presence of over 300 functional genes in the human genome becomes a daunting task. Thus, the characterization of individuals with a genetic susceptibility to altered olfaction coupled with the absence of particular olfactory receptor genes will allow phenotype/genotype correlations and vindicate the function of specific olfactory receptors with their cognate ligands. We characterized a 118 kb Ξ²-globin deletion and found that its 3β² end breakpoint extends to the neighboring olfactory receptor region downstream of the Ξ²-globin gene cluster. This deletion encompasses six contiguous olfactory receptor genes (OR51V1, OR52Z1, OR51A1P, OR52A1, OR52A5, and OR52A4) all of which are expressed in the brain. Topology analysis of the encoded proteins from these olfactory receptor genes revealed that OR52Z1, OR52A1, OR52A5, and OR52A4 are predicted to be functional receptors as they display integral characteristics of G-proteins coupled receptors. Individuals homozygous for the 118 kb Ξ²-globin deletion are afflicted with Ξ²-thalassemia due to a homozygous deletion of the Ξ²-globin gene and have no alleles for the above mentioned olfactory receptors genes. This is the first example of a homozygous deletion of olfactory receptor genes in human. Although altered olfaction remains to be ascertained in these individuals, such a study can be carried out in Ξ²-thalassemia patients from Malaysia, Indonesia and the Philippines where this mutation is common. Furthermore, OR52A1 contains a Ξ³-globin enhancer, which was previously shown to confer continuous expression of the fetal Ξ³-globin genes. Thus, the hypothesis that Ξ²-thalassemia individuals, who are homozygous for the 118 kb deletion, may also have an exacerbation of their anemia due to the deletion of two copies of the Ξ³-globin enhancer element is worthy of consideration
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