63 research outputs found

    A flaring X-ray pulsar in Dorado

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    A study of unusual gamma-ray bursts detected on March 5 and March 6, 1979 in the KONUS experiment on the Venera 11 and Venera 12 spacecraft shows their source to be flaring X-ray pulsar in Dorado

    Torque Teno Virus (TTV) distribution in healthy Russian population

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    <p>Abstract</p> <p>Background</p> <p>Torque teno virus (TTV) is a circular, single-stranded DNA virus that chronically infects healthy individuals of all ages worldwide. There is a lot of data on the prevalence and genetic heterogeneity of TTV in healthy populations and in patients with various diseases now available. However, little is known about TTV load among healthy human population. In this study we analyzed TTV load in the group of 512 Russian elite athletes, who are supposed to be, by some standards, the healthiest part of the human population.</p> <p>Results</p> <p>The prevalence rate of TTV among the Russian Olympic Reserve members was 94% (for test sensitivity about 1000 genome equivalents per 1 ml of blood). Quantities varied from 10<sup>3 </sup>(which corresponded to detection limit) to 10<sup>10 </sup>copies per 1 ml of blood, with median at 2.7 × 10<sup>6 </sup>copies.</p> <p>Conclusion</p> <p>About 94% of healthy individuals in Russian population have more than 1000 TTV genome copies per 1 ml of blood. This result exceeds the previously published data, and can be explained by either more sensitive PCR test system or by higher TTV distribution in Russian population or both. TTV viral load neither depends on gender, nor age.</p

    Hypersharp Neutrino Lines

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    Neutrino lines from very long lived nuclei in simple crystals such as metals have hypersharp natural width, motionally narrowed by lattice vibrations in analogy to recoilless emission. A generalized hypersharp line fraction including the recoilless part can be derived in a frequency modulation approach. The nue lines of natural width in 3H to 3He 2-body beta-decay can then be resonantly captured with geometrical cross section. The extreme sharpness DeltaE/E~10-29 of the tritium nue line can probe the Planck length L via its limits on the widths of states, DeltaE/E(L) =L(L/R)beta =10-20(beta ~1) to 10-40 (beta= L/R(fm)). Stringent limits can be set on beta, thus, on models of quantum gravity

    Parallel Driving and Modulatory Pathways Link the Prefrontal Cortex and Thalamus

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    Pathways linking the thalamus and cortex mediate our daily shifts from states of attention to quiet rest, or sleep, yet little is known about their architecture in high-order neural systems associated with cognition, emotion and action. We provide novel evidence for neurochemical and synaptic specificity of two complementary circuits linking one such system, the prefrontal cortex with the ventral anterior thalamic nucleus in primates. One circuit originated from the neurochemical group of parvalbumin-positive thalamic neurons and projected focally through large terminals to the middle cortical layers, resembling ‘drivers’ in sensory pathways. Parvalbumin thalamic neurons, in turn, were innervated by small ‘modulatory’ type cortical terminals, forming asymmetric (presumed excitatory) synapses at thalamic sites enriched with the specialized metabotropic glutamate receptors. A second circuit had a complementary organization: it originated from the neurochemical group of calbindin-positive thalamic neurons and terminated through small ‘modulatory’ terminals over long distances in the superficial prefrontal layers. Calbindin thalamic neurons, in turn, were innervated by prefrontal axons through small and large terminals that formed asymmetric synapses preferentially at sites with ionotropic glutamate receptors, consistent with a driving pathway. The largely parallel thalamo-cortical pathways terminated among distinct and laminar-specific neurochemical classes of inhibitory neurons that differ markedly in inhibitory control. The balance of activation of these parallel circuits that link a high-order association cortex with the thalamus may allow shifts to different states of consciousness, in processes that are disrupted in psychiatric diseases

    A thalamic reticular networking model of consciousness

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    <p>Abstract</p> <p>[Background]</p> <p>It is reasonable to consider the thalamus a primary candidate for the location of consciousness, given that the thalamus has been referred to as the gateway of nearly all sensory inputs to the corresponding cortical areas. Interestingly, in an early stage of brain development, communicative innervations between the dorsal thalamus and telencephalon must pass through the ventral thalamus, the major derivative of which is the thalamic reticular nucleus (TRN). The TRN occupies a striking control position in the brain, sending inhibitory axons back to the thalamus, roughly to the same region where they receive afferents.</p> <p>[Hypotheses]</p> <p>The present study hypothesizes that the TRN plays a pivotal role in dynamic attention by controlling thalamocortical synchronization. The TRN is thus viewed as a functional networking filter to regulate conscious perception, which is possibly embedded in thalamocortical networks. Based on the anatomical structures and connections, modality-specific sectors of the TRN and the thalamus appear to be responsible for modality-specific perceptual representation. Furthermore, the coarsely overlapped topographic maps of the TRN appear to be associated with cross-modal or unitary conscious awareness. Throughout the latticework structure of the TRN, conscious perception could be accomplished and elaborated through accumulating intercommunicative processing across the first-order input signal and the higher-order signals from its functionally associated cortices. As the higher-order relay signals run cumulatively through the relevant thalamocortical loops, conscious awareness becomes more refined and sophisticated.</p> <p>[Conclusions]</p> <p>I propose that the thalamocortical integrative communication across first- and higher-order information circuits and repeated feedback looping may account for our conscious awareness. This TRN-modulation hypothesis for conscious awareness provides a comprehensive rationale regarding previously reported psychological phenomena and neurological symptoms such as blindsight, neglect, the priming effect, the threshold/duration problem, and TRN-impairment resembling coma. This hypothesis can be tested by neurosurgical investigations of thalamocortical loops via the TRN, while simultaneously evaluating the degree to which conscious perception depends on the severity of impairment in a TRN-modulated network.</p

    ТРАНСПЛАНТИРОВАННОЕ СЕРДЦЕ. ПРАВОЖЕЛУДОЧКОВАЯ НЕДОСТАТОЧНОСТЬ, ОТТОРЖЕНИЕ ИЛИ МИОКАРДИТ?

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    The differentiation of the cases of the right ventricular failure in transplanted heart should be complex and challenging. The 28-year old man with dilated cardiomyopathy underwent orthotopic heart transplantation. After transplantation developed right ventricular failure. The biopsy (n = 5) didn’t reveal any signs of myocardial rejection. There were noted some signs of inflammation in lateral right ventricular wall only by gated SPECT. The right ventricular failure increased and 6 months later there was successfully performed the heart retransplantation on the patient. The virusological study revealed the Epstein–Barr virus in myocardium. The explanted heart research excluded limphoproliferative disease by immunogystochemical tests. The final diagnosis is myocarditis. Дифференцирование причин правожелудочковой недостаточности пересаженного сердца должно быть комплексным. Мужчина 28 лет с дилатационной кардиомиопатией был подвергнут ортотопической трансплантации сердца. После трансплантации развилась прогрессирующая правожелудочковая недо- статочность. Биопсия (в количестве 5) не выявила признаков отторжения миокарда. Только при gated SPECT были отмечены признаки воспаления в боковой стенке ПЖ. Правожелудочковая недостаточность нарастала, и спустя 6 месяцев больному успешно была выполнена ретрансплантация сердца. Вирусоло- гическое исследование выявило наличие вируса Эпштейна–Барр в миокарде. Иммуногистохимические исследования эксплантированного сердца исключили лимфопролиферативное заболевание. Заключи- тельный диагноз – миокардит.

    Consensus Paper: Towards a Systems-Level View of Cerebellar Function: the Interplay Between Cerebellum, Basal Ganglia, and Cortex

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