350 research outputs found
Polarization of Astronomical Maser Radiation. IV. Circular Polarization Profiles
Profile comparison of the Stokes parameters and is a powerful tool
for maser data analysis, providing the first direct methods for unambiguous
determination of (1) the maser saturation stage, (2) the amplification optical
depth and intrinsic Doppler width of unsaturated masers, and (3) the
comparative magnitudes of Zeeman splitting and Doppler linewidth. Circular
polarization recently detected in OH 1720 MHz emission from the Galactic center
appears to provide the first direct evidence for maser saturation.Comment: 14 pages, 1 Postscript figures (included), uses aaspp4.sty. To appear
in Astrophysical Journa
Disruption of VGLUT1 in cholinergic medial habenula projections increases nicotine self-administration
Cholinergic projections from the medial habenula (MHb) to the interpeduncular nucleus (IPN) have been studied for their complex contributions to nicotine addiction and have been implicated in nicotine reinforcement, aversion, and withdrawal. While it has been established that MHb cholinergic projections co-release glutamate, no direct evidence has demonstrated a role for this glutamate projection in nicotine consumption. In the present study, a novel floxed Slc17a7 (VGLUT1) mouse was generated and used to create conditional knockout (cKO) mice that lack VGLUT1 in MHb cholinergic neurons. Loss of Slc17a7 expression in ventral MHb cholinergic neurons was validated using fluorescent in situ hybridization, and immunohistochemistry was used to demonstrate a corresponding reduction of VGLUT1 protein in cholinergic terminals in the IPN. We also used optogenetics-assisted electrophysiology to evoke excitatory post-synaptic currents in IPN and observed a reduction of glutamatergic currents in the cKO, supporting the functional disruption of VGLUT1 in MHb to IPN synapses. cKO mice exhibited no gross phenotypic abnormalities and displayed normal thigmotaxis and locomotor behavior in the open-field assay. When trained to lever press for food, there was no difference between control and cKO. However, when tested in a nicotine self-administration procedure we found that the loss of VGLUT1-mediated glutamate co-release led to increased responding for nicotine. These findings indicate that glutamate co-release from ventral MHb cholinergic neurons opposes nicotine self-administration, and provide additional support for targeting this synapse to develop potential treatments for nicotine addiction
Асинхронный электропривод неполно-поворотной заслонки
В процессе работы были исследованы переходные процессы модели привода ГУСАР при закрытии заслонки, открытии, повороте на несколько градусов градус, при пониженном напряжении сети.
Дипломный проект содержит описание требований предъявляемых к электроприводу заслонки, разработанный алгоритм формирования момента, разработанную модель электропривода заслонки в среде Matlab Simulink.
Рассчитаны технико-экономические показатели; рассмотрены основные вопросы экологичности и безопасности проекта.In the process, the transient processes of the GUSAR drive model were studied with the shutter closed, opening, turning several degrees, with a reduced network voltage.
The graduation project contains a description of the requirements for an electric drive damper, developed by an algorithm for generating a moment, developed by a model of an electric drive damper in a Matlab Simulink environment.
Technical and economic indicators are calculated; The main issues of environmental friendliness and safety of the project are considered
International Space Station Research for the Next Decade: International Coordination and Research Accomplishments
During 2011, the International Space Station reached an important milestone in the completion of assembly and the shift to the focus on a full and continuous utilization mission in space. The ISS partnership itself has also met a milestone in the coordination and cooperation of utilization activities including research, technology development and education. We plan and track all ISS utilization activities jointly and have structures in place to cooperate on common goals by sharing ISS assets and resources, and extend the impacts and efficiency of utilization activities. The basic utilization areas on the ISS include research, technology development and testing, and education/outreach. Research can be categorized as applied research for future exploration, basic research taking advantage of the microgravity and open space environment, and Industrial R&D / commercial research focused at industrial product development and improvement. Technology development activities range from testing of new spacecraft systems and materials to the use of ISS as an analogue for future exploration missions to destinations beyond Earth orbit. This presentation, made jointly by all ISS international partners, will highlight the ways that international cooperation in all of these areas is achieved, and the overall accomplishments that have come as well as future perspectives from the cooperation. Recently, the partnership has made special efforts to increase the coordination and impact of ISS utilization that has humanitarian benefits. In this context the paper will highlight tentative ISS utilization developments in the areas of Earth remote sensing, medical technology transfer, and education/outreach
Laser Spectroscopic Technique for Direct Identification of a Single Virus I: FASTER CARS
From the famous 1918 H1N1 influenza to the present COVID-19 pandemic, the
need for improved virial detection techniques is all too apparent. The aim of
the present paper is to show that identification of individual virus particles
in clinical sample materials quickly and reliably is near at hand. First of
all, our team has developed techniques for identification of virions based on a
modular atomic force microscopy (AFM). Furthermore, Femtosecond Adaptive
Spectroscopic Techniques with Enhanced Resolution via Coherent Anti-Stokes
Raman Scattering (FASTER CARS) [1] using tip-enhanced techniques markedly
improves the sensitivity.Comment: 16 pages, 3 figure
Recommended from our members
Laser spectroscopic technique for direct identification of a single virus I: FASTER CARS
From the famous 1918 H1N1 influenza to the present COVID-19 pandemic, the need for improved viral detection techniques is all too apparent. The aim of the present paper is to show that identification of individual virus particles in clinical sample materials quickly and reliably is near at hand. First of all, our team has developed techniques for identification of virions based on a modular atomic force microscopy (AFM). Furthermore, femtosecond adaptive spectroscopic techniques with enhanced resolution via coherent anti-Stokes Raman scattering (FASTER CARS) using tip-enhanced techniques markedly improves the sensitivity [M. O. Scully, et al, Proc. Natl. Acad. Sci. U.S.A. 99, 10994-11001 (2002)]
Lifetime determination of excited states in Cd-106
Two separate experiments using the Differential Decay Curve Method have been performed to extract mean lifetimes of excited states in 106 Cd. The inedium-spin states of interest were populated by the Mo-98(C-12, 4n) Cd-106 reaction performed at the Wright Nuclear Structure Lab., Yale University. From this experiment, two isomeric state mean lifetimes have been deduced. The low-lying states were populated by the Mo-96(C-13, 3n)Cd-106 reaction performed at the Institut fur Kernphysik, Universitat zu Koln. The mean lifetime of the I-pi = 2(1)(+) state was deduced, tentatively, as 16.4(9) ps. This value differs from the previously accepted literature value from Coulomb excitation of 10.43(9) ps
Lifetime measurements in Co and Co
Lifetimes of the and states in Co and the
state in Co were measured using the recoil distance Doppler
shift and the differential decay curve methods. The nuclei were populated by
multi-nucleon transfer reactions in inverse kinematics. Gamma rays were
measured with the EXOGAM Ge array and the recoiling fragments were fully
identified using the large-acceptance VAMOS spectrometer. The E2 transition
probabilities from the and states to the ground
state could be extracted in Co as well as an upper limit for the
(E2) value in Co. The experimental
results were compared to large-scale shell-model calculations in the and
model spaces, allowing to draw conclusions on the single-particle
or collective nature of the various states.Comment: 8 pages, 8 figures, 1 table, accepted for publication in Physical
Review
In-beam fast-timing measurements in 103,105,107Cd
Fast-timing measurements were performed recently in the region of the
medium-mass 103,105,107Cd isotopes, produced in fusion evaporation reactions.
Emitted gamma-rays were detected by eight HPGe and five LaBr3:Ce detectors
working in coincidence. Results on new and re-evaluated half-lives are
discussed within a systematic of transition rates. The states in
103,105,107Cd are interpreted as arising from a single-particle excitation. The
half-life analysis of the states in 103,105,107Cd shows no change in
the single-particle transition strength as a function of the neutron number
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