32 research outputs found

    Experiments at the W.M. Keck Observatory to support the Thirty Meter Telescope design work

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    In order to validate various assumptions about the operating environment of the Thirty Meter Telescope (TMT), to validate the modeling packages being used to guide the design work for the TMT and to directly investigate the expected operation of several subsystems we have embarked on an extensive campaign of environmental measurements at the Keck telescopes. We have measured and characterized the vibration environment around the observatory floor and at certain locations on the telescope over a range of operating conditions. Similarly the acoustic environment around the telescope and primary mirror has been characterized for frequencies above 2 Hz. The internal and external wind and temperature fields are being measured using combined sonic anemometer and PRT sensors. We are measuring the telescope position error and drive torque signals in order to investigate the wind induced telescope motions. A scintillometer mounted on the telescope is measuring the optical turbulence inside the telescope tube. This experimental work is supplemented by an extensive analysis of telescope and engineering sensor log files and measurements, primarily those of accelerometers located on the main telescope optics, primary mirror segment edge sensor error signals (residuals), telescope structure temperature measurements and the telescope status information

    MAGIQ at the W. M. Keck Observatory: initial deployment of a new acquisition, guiding, and image quality monitoring system

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    The W. M. Keck Observatory has completed the development and initial deployment of MAGIQ, the Multi-function Acquisition, Guiding and Image Quality monitoring system. MAGIQ is an integrated system for acquisition, guiding and image quality measurement for the Keck telescopes. This system replaces the acquisition and guiding hardware and software for existing instruments at the Observatory and is now the standard for visible wavelength band acquisition cameras for future instrumentation. In this paper we report on the final design and implementation of this new system, which includes three major components: a visible wavelength band acquisition camera, image quality measurement capability, and software for acquisition, guiding and image quality monitoring. The overall performance is described, as well as the details of our approach to integrating low order wavefront sensing capability in order to provide closed loop control of telescope focus

    Experiments at the W.M. Keck Observatory to support the Thirty Meter Telescope design work

    Get PDF
    In order to validate various assumptions about the operating environment of the Thirty Meter Telescope (TMT), to validate the modeling packages being used to guide the design work for the TMT and to directly investigate the expected operation of several subsystems we have embarked on an extensive campaign of environmental measurements at the Keck telescopes. We have measured and characterized the vibration environment around the observatory floor and at certain locations on the telescope over a range of operating conditions. Similarly the acoustic environment around the telescope and primary mirror has been characterized for frequencies above 2 Hz. The internal and external wind and temperature fields are being measured using combined sonic anemometer and PRT sensors. We are measuring the telescope position error and drive torque signals in order to investigate the wind induced telescope motions. A scintillometer mounted on the telescope is measuring the optical turbulence inside the telescope tube. This experimental work is supplemented by an extensive analysis of telescope and engineering sensor log files and measurements, primarily those of accelerometers located on the main telescope optics, primary mirror segment edge sensor error signals (residuals), telescope structure temperature measurements and the telescope status information

    Spinal trigeminal neurons demonstrate an increase in responses to dural electrical stimulation in the orofacial formalin test

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    Primary headaches are often associated with pain in the maxillofacial region commonly classified under the term “orofacial pain” (OFP). In turn, long-lasting OFP can trigger and perpetuate headache as an independent entity, which is able to persist after the resolution of the main disorder. A close association between OFP and headache complicates their cause and effect definition and leads to misdiagnosis. The precise mechanisms underlying this phenomenon are poorly understood, partly because of the deficiency of research-related findings. We combined the animal models of OFP and headache—the orofacial formalin test and the model of trigeminovascular nociception—to investigate the neurophysiological mechanisms underlying their comorbidity. In anesthetized rats, the ongoing activity of single convergent neurons in the spinal trigeminal nucleus was recorded in parallel to their responses to the electrical stimulation of the dura mater before and after the injection of formalin into their cutaneous receptive fields. Subcutaneous formalin resulted not only in the biphasic increase in the ongoing activity, but also in an enhancement of neuronal responses to dural electrical stimulation, which had similar time profile. These results demonstrated that under tonic pain in the orofacial region a nociceptive signaling from the dura mater to convergent trigeminal neurons is significantly enhanced apparently because of the development of central sensitization; this may contribute to the comorbidity of OFP and headache

    QM/MM Description of Newly Selected Catalytic Bioscavengers Against Organophosphorus Compounds Revealed Reactivation Stimulus Mediated by Histidine Residue in the Acyl-Binding Loop

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    Butyrylcholinesterase (BChE) is considered as an efficient stoichiometric antidote against organophosphorus (OP) poisons. Recently we utilized combination of calculations and ultrahigh-throughput screening (uHTS) to select BChE variants capable of catalytic destruction of OP pesticide paraoxon. The purpose of this study was to elucidate the molecular mechanism underlying enzymatic hydrolysis of paraoxon by BChE variants using hybrid quantum mechanical/molecular mechanical (QM/MM) calculations. Detailed analysis of accomplished QM/MM runs revealed that histidine residues introduced into the acyl-binding loop are always located in close proximity with aspartate residue at position 70. Histidine residue acts as general base thus leading to attacking water molecule activation and subsequent SN2 inline hydrolysis resulting in BChE reactivation. This combination resembles canonical catalytic triad found in active centers of various proteases. Carboxyl group activates histidine residue by altering its pKa, which in turn promotes the activation of water molecule in terms of its nucleophilicity. Observed re-protonation of catalytic serine residue at position 198 from histidine residue at position 438 recovers initial configuration of the enzyme’s active center, facilitating next catalytic cycle. We therefore suggest that utilization of uHTS platform in combination with deciphering of molecular mechanisms by QM/MM calculations may significantly improve our knowledge of enzyme function, propose new strategies for enzyme design and open new horizons in generation of catalytic bioscavengers against OP poisons

    MAGIQ at the W. M. Keck Observatory: initial deployment of a new acquisition, guiding, and image quality monitoring system

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    The W. M. Keck Observatory has completed the development and initial deployment of MAGIQ, the Multi-function Acquisition, Guiding and Image Quality monitoring system. MAGIQ is an integrated system for acquisition, guiding and image quality measurement for the Keck telescopes. This system replaces the acquisition and guiding hardware and software for existing instruments at the Observatory and is now the standard for visible wavelength band acquisition cameras for future instrumentation. In this paper we report on the final design and implementation of this new system, which includes three major components: a visible wavelength band acquisition camera, image quality measurement capability, and software for acquisition, guiding and image quality monitoring. The overall performance is described, as well as the details of our approach to integrating low order wavefront sensing capability in order to provide closed loop control of telescope focus

    THE MORPHOLOGICAL CHARACTERISTICS OF THE KEDNEY NEPHRON IN THE ONTOGENESIS AND EXPERIMENT

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    The systemic data of the morphometric investigation of the kedney nephrons have been given with the characteristic of the quantitative laws and correlative analysis of the different generations nephrons dimensional values dynamics in the ontogenesis and in the experiment. The succession of the differentiation and reaction of nephrons and its sections has been shown. The new objective indicators of the intranephron integration of the kedney nephron sections in ontogenesis and experiment can serve as the scientific base for teh objective evaluation of the kedney age, decoding of peculiarities of its age pathology, the right interpretation of the physiological and pathological variations. The method of formation of the kedney nephron sections in the implants has been developed, the methodical recommendations on the kedney morphometry with the introduction in the interenterprise level have been given. The new methods of the integrative morphometry increase the efficiency and validity of the organ state evalution and open the new direction of the morphological investigations. The field of application: the anatomy, the histology, nephrology, patanatomy, the legal medicineAvailable from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio

    Behavior of Chinchilla lanigera under cage keeping with the introduction of molecular hydrogen into the diet

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    Study of the effect of molecular hydrogen on the behavior adaptation of chinchilla in conditions of cage keeping. The experimental animals received drinking water enriched with molecular hydrogen at a dosage of 0.1-1.1 ppm for 10 months. It was found that the peak of activity of the behavior of chinchillas of both groups fell on the period from 19:00 to 9:00. A significant difference between the experimental and control groups were identified by the shape of behavior “movement within the cage” activity in experimental group daytime was higher at 24 minutes (p˂0.05) than in the control. The dynamics of daily activity of experimental animals came eh for the period from 19:00 to 08:00 (on average by 12 minutes) and the control group - 22:00-08:00 (an average of 6 minutes). The introduction of drinking water enriched with molecular hydrogen into the diet of the experimental group of chinchillas for 10 months increased the proportion of active behavior of animals by 20.6%
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