Temperature Manipulation in Songbird Brain Implicates the Premotor Nucleus HVC in Birdsong Syntax.

Variable motor sequences of animals are often structured and can be described by probabilistic transition rules between action elements. Examples include the songs of many songbird species such as the Bengalese finch, which consist of stereotypical syllables sequenced according to probabilistic rules (song syntax). The neural mechanisms behind such rules are poorly understood.

Spectrum and Frequency of the GJB2 Gene Pathogenic Variants in a Large Cohort of Patients with Hearing Impairment Living in a Subarctic Region of Russia (the Sakha Republic).

Pathogenic variants in the GJB2 gene, encoding connexin 26, are known to be a major cause of hearing impairment (HI). More than 300 allelic variants have been identified in the GJB2 gene. Spectrum and allelic frequencies of the GJB2 gene vary significantly among different ethnic groups worldwide.

DIAGNOSTICS ALGORITHM OF DIABETIC POLYNEUROPATHY IN PREDICTION OF CLINICAL COURSE.

Aim: To estimate the importance of new algorithm introducing of PDP diagnostics in practice of NEFU medical institute Clinic in detection of severity level and predicting of clinical course.

Materials And Methods: 50 people with sensory-motor PDP form among patients with 2 type diabetes were examined on the basis of Clinic of NEFU medical institute. Patients have been divided into 2 groups by disease duration: the first groups were patients with duration of disease till 10 years, the second group--more than 10 years.

[Sociological analysis of healthcare delivery in Russia regions with inclement natural conditions (in case of the Republic of Altai)].

The paper describes the results of a sociological study of delivery of healthcare in the Republic of Altai to search for ways to improve its quality and to provide access to the local population. Analysis was made with regard to an interdisciplinary, comprehensive approach to considering the range of problems associated with not only the health of local residents and identifying risk factors leading to diseases, but also by determining the possibilities that could promote the minimization of causes that have a considerable impact on the occurrence of diseases and also hamper healthcare delivery in the human settlements of Gornyi Altai, which are difficult of access. The investigation has used sociological and statistical methods.

Age-Related Hearing Impairment (ARHI) associated with GJB2 single mutation IVS1+1G>A in the Yakut population isolate in Eastern Siberia.

Age-Related Hearing Impairment (ARHI) is one of the frequent sensory disorders registered in 50% of individuals over 80 years. ARHI is a multifactorial disorder due to environmental and poor-known genetic components. In this study, we present the data on age-related hearing impairment of 48 heterozygous carriers of mutation IVS1+1G>A (GJB2 gene) and 97 subjects with GJB2 genotype wt/wt in the Republic of Sakha/Yakutia (Eastern Siberia, Russia).

A compact statistical model of the song syntax in Bengalese finch.

Songs of many songbird species consist of variable sequences of a finite number of syllables. A common approach for characterizing the syntax of these complex syllable sequences is to use transition probabilities between the syllables. This is equivalent to the Markov model, in which each syllable is associated with one state, and the transition probabilities between the states do not depend on the state transition history.

Singing-related activity of identified HVC neurons in the zebra finch.

High vocal center (HVC) is part of the premotor pathway necessary for song production and is also a primary source of input to the anterior forebrain pathway (AFP), a basal ganglia-related circuit essential for vocal learning. We have examined the activity of identified HVC neurons of zebra finches during singing. Antidromic activation was used to identify three classes of HVC cells: neurons projecting to the premotor nucleus RA, neurons projecting to area X in the AFP, and putative HVC interneurons.

Sleep-related neural activity in a premotor and a basal-ganglia pathway of the songbird.

During singing, neurons in premotor nucleus RA (robust nucleus of the arcopallium) of the zebra finch produce complex temporal sequences of bursts that are recapitulated during sleep. RA receives input from nucleus HVC via the premotor pathway, and also from the lateral magnocellular nucleus of the anterior nidopallium (LMAN), part of a basal ganglia-related circuit essential for vocal learning. We explore the propagation of sleep-related spike patterns in these two pathways and their influences on RA activity.

Neural mechanisms of vocal sequence generation in the songbird.

Little is known about the biophysical and neuronal circuit mechanisms underlying the generation and learning of behavioral sequences. Songbirds provide a marvelous animal model in which to study these phenomena. By use of a motorized microdrive to record the activity of single neurons in the singing bird, we are beginning to understand the circuits that generate complex vocal sequences.

Phase sensitive shot noise in an Andreev interferometer.

We investigate nonequilibrium noise in a diffusive Andreev interferometer, in which currents emerging from two normal metal/superconductor (N-S) interfaces can interfere. We observe a modulation of the shot noise when the phase difference between the two N-S interfaces is varied by a magnetic flux. This is the signature of phase-sensitive fluctuations in the normal metal.

An ultra-sparse code underlies the generation of neural sequences in a songbird.

Sequences of motor activity are encoded in many vertebrate brains by complex spatio-temporal patterns of neural activity; however, the neural circuit mechanisms underlying the generation of these pre-motor patterns are poorly understood. In songbirds, one prominent site of pre-motor activity is the forebrain robust nucleus of the archistriatum (RA), which generates stereotyped sequences of spike bursts during song and recapitulates these sequences during sleep. We show that the stereotyped sequences in RA are driven from nucleus HVC (high vocal centre), the principal pre-motor input to RA.

Observation of photon-assisted noise in a diffusive normal metal-superconductor junction.

We report measurements of nonequilibrium noise in a diffusive normal metal-superconductor (N-S) junction in the presence of both dc bias and high-frequency ac excitation. We find that the shot noise of a diffusive N-S junction is doubled compared to a normal diffusive conductor. Under ac excitation of frequency nu the shot noise develops features at bias voltages |V| = hnu/(2e), which bear all the hallmarks of a photon-assisted process.

Observation of the Cabibbo-Suppressed Decay Ξ_{c}^{+} → pK^{-}π^{+}.

We report the first observation of the Cabibbo-suppressed charm baryon decay Ξ_{c}^{+}→pK^{-}π^{+}. We observe 150±22±5 events for the signal. The data were accumulated using the SELEX spectrometer during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 GeV/c Σ^{-} beam.

The radio-frequency single-electron transistor (RF-SET): A fast and ultrasensitive electrometer.

A new type of electrometer is described that uses a single-electron transistor (SET) and that allows large operating speeds and extremely high charge sensitivity. The SET readout was accomplished by measuring the damping of a 1.7-gigahertz resonant circuit in which the device is embedded, and in some ways is the electrostatic "dual" of the well-known radio-frequency superconducting quantum interference device.

[Blood flow in a renal artery with a deformed vessel wall].

Blood flow in a vessel of the kidney arterium type with a deformed vascular wall in the form of stenosis or atherosclerotic patches is described. Rate fields and pressure distribution in the vessel are described. Conclusions are made concerning the behaviour of blood forming elements.