1,221 research outputs found
Single or joint amplitude distribution analyzer Patent
Cathode ray oscilloscope for analyzing electrical waveforms representing amplitude distribution of time functio
Effect of androgen treatment during foetal and/or neonatal life on ovarian function in prepubertal and adult rats
We investigated the effects of different windows of testosterone propionate (TP) treatment during foetal and neonatal life in female rats to determine whether and when excess androgen exposure would cause disruption of adult reproductive function. Animals were killed prepubertally at d25 and as adults at d90. Plasma samples were taken for hormone analysis and ovaries serial sectioned for morphometric analyses. In prepubertal animals, only foetal+postnatal and late postnatal TP resulted in increased body weights, and an increase in transitory, but reduced antral follicle numbers without affecting total follicle populations. Treatment with TP during both foetal+postnatal life resulted in the development of streak ovaries with activated follicles containing oocytes that only progressed to a small antral (smA) stage and inactive uteri. TP exposure during foetal or late postnatal life had no effect upon adult reproductive function or the total follicle population, although there was a reduction in the primordial follicle pool. In contrast, TP treatment during full postnatal life (d1-25) resulted in anovulation in adults (d90). These animals were heavier, had a greater ovarian stromal compartment, no differences in follicle thecal cell area, but reduced numbers of anti-Mullerian hormone-positive smA follicles when compared with controls. Significantly reduced uterine weights lead reduced follicle oestradiol production. These results support the concept that androgen programming of adult female reproductive function occurs only during specific time windows in foetal and neonatal life with implications for the development of polycystic ovary syndrome in women
Photoresponse of polyaniline-functionalized graphene quantum dots
Polyaniline-functionalized graphene quantum dots (PANI-GQD) and pristine graphene quantum dots (GQDs) were utilized for optoelectronic devices. The PANI-GQD based photodetector exhibited higher responsivity which is about an order of magnitude at 405 nm and 7 folds at 532 nm as compared to GQD-based photodetectors. The improved photoresponse is attributed to the enhanced interconnection of GQD by island-like polymer matrices, which facilitate carrier transport within the polymer matrices. The optically tunable current–voltage (I–V) hysteresis of PANI-GQD was also demonstrated. The hysteresis magnifies progressively with light intensity at a scan range of ±1 V. Both GQD and PANI-GQD devices change from positive to negative photocurrent when the bias reaches 4 V. Photogenerated carriers are excited to the trapping states in GQDs with increased bias. The trapped charges interact with charges injected from the electrodes which results in a net decrease of free charge carriers and a negative photocurrent. The photocurrent switching phenomenon in GQD and PANI-GQD devices may open up novel applications in optoelectronics
Tangential vitreous traction: a possible mechanism of development of cystoid macular edema in retinitis pigmentosa
We report the possible mechanism of development of cystoid macular edema (CME) in retinitis pigmentosa (RP) in the case of a 68-year-old woman with RP and CME in the right eye and resolving CME in the left eye. Spectral domain optical coherence tomography showed CME and posterior vitreoschisis in the nasal quadrant of the fundus without a posterior vitreous detachment (PVD). This vitreous pathology suggested bilateral thickening and shrinkage of the posterior vitreous cortex. In the right eye, CME was evident with no vitreofoveal separation. However, in the left eye, minimal change was seen in the CME associated with a focal shallow PVD over the fovea. The best-corrected visual acuity (BCVA) in the left eye increased to 0.3 from 0.15 7 years after the first visit. Tangential vitreous traction on the macula may have caused the CME in the right eye. The shallow PVD over the fovea might have released the tangential vitreous traction from the fovea, induced spontaneous resolution of the CME, and improved the BCVA in the left eye
Host Factors interacting with the Pestivirus N terminal protease, Npro are Components of the Ribonucleoprotein Complex
The viral N-terminal protease N(pro) of pestiviruses counteracts cellular antiviral defenses through inhibition of IRF3. Here we used mass spectrometry to identify a new role for N(pro) through its interaction with over 55 associated proteins, mainly ribosomal proteins and ribonucleoproteins, including RNA helicase A (DHX9), Y-box binding protein (YBX1), DDX3, DDX5, eIF3, IGF2BP1, multiple myeloma tumor protein 2, interleukin enhancer binding factor 3 (IEBP3), guanine nucleotide binding protein 3, and polyadenylate-binding protein 1 (PABP-1). These are components of the translation machinery, ribonucleoprotein particles (RNPs), and stress granules. Significantly, we found that stress granule formation was inhibited in MDBK cells infected with a noncytopathic bovine viral diarrhea virus (BVDV) strain, Kyle. However, ribonucleoproteins binding to N(pro) did not inhibit these proteins from aggregating into stress granules. N(pro) interacted with YBX1 though its TRASH domain, since the mutant C112R protein with an inactive TRASH domain no longer redistributed to stress granules. Interestingly, RNA helicase A and La autoantigen relocated from a nuclear location to form cytoplasmic granules with N(pro). To address a proviral role for N(pro) in RNP granules, we investigated whether N(pro) affected RNA interference (RNAi), since interacting proteins are involved in RISC function during RNA silencing. Using glyceraldehyde-3-phosphate dehydrogenase (GAPDH) silencing with small interfering RNAs (siRNAs) followed by Northern blotting of GAPDH, expression of N(pro) had no effect on RNAi silencing activity, contrasting with other viral suppressors of interferon. We propose that N(pro) is involved with virus RNA translation in the cytoplasm for virus particle production, and when translation is inhibited following stress, it redistributes to the replication complex. IMPORTANCE Although the pestivirus N-terminal protease, N(pro), has been shown to have an important role in degrading IRF3 to prevent apoptosis and interferon production during infection, the function of this unique viral protease in the pestivirus life cycle remains to be elucidated. We used proteomic mass spectrometry to identify novel interacting proteins and have shown that N(pro) is present in ribosomal and ribonucleoprotein particles (RNPs), indicating a translational role in virus particle production. The virus itself can prevent stress granule assembly from these complexes, but this inhibition is not due to N(pro). A proviral role to subvert RNA silencing through binding of these host RNP proteins was not identified for this viral suppressor of interferon
Virtual design bureau
В статье описывается краткая история Виртуального конструкторского бюро космического приборостроения за 5 лет его существования. В статье можно прочитать об основных, но при этом наиболее важных событиях в жизни ВКБ и кафедры точного приборостроения за этот период. ВКБ сыграло значительную роль в определении направления развитии кафедры. Самыми значимыми проектами являются создание студенческого Центра управления полетами космическими аппаратами и участие взапуске спутника "Томск-ТПУ-120".The article describes a brief 5-year history of the Virtual Design Bureau. In the article you can read about the most important events in the life of the VDB and the Department of Precision Instrument Making for this period. VDB played a significant role in determining the department development direction. The most significant projects are the creation of a student space flight control center and participation in the launch of the Tomsk-TPU-120 satellite
Development Status of Wideband Millimeter-Wave Receivers for LMT-FINER
Spectroscopic observations of the far-infrared [O III] and [C II] lines
present a pathway to explore the mechanisms of the emergence of massive
galaxies in the epoch of reionization and beyond, which is one of the most
fundamental questions in astronomy. To address this question, the Far-Infrared
Nebular Emission Receiver (FINER) project is developing two wideband
dual-polarization sideband-separating heterodyne receivers at 120--210 GHz and
210--360 GHz for the Large Millimeter Telescope (LMT) in Mexico. Compared with
Atacama Large Millimeter/submillimeter Array (ALMA), LMT provides 40% of ALMA's
light-collecting area and a similar atmospheric transmittance, but FINER plans
to have an instantaneous intermediate frequency (IF) of 3--21 GHz per sideband
per polarization which is five times wider than current ALMA's bandwidth.
Therefore, FINER is going to offer cutting-edge spectral scanning capability in
the next several years.
The project is currently in an active development phase. In this proceeding,
the latest development status for FINER, including the optics, wideband
waveguide components as well as low-noise
superconductor-insulator-superconductor (SIS) mixers is reported.Comment: 14 pages, 8 figures, 1 table. Proceeding paper presented in SPIE
Astronomical Telescope and Instrumentation 202
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