5,367 research outputs found
Role of ATM signaling in PALB2-dependent DNA damage responses
Poster presentation - Theme 1: Cell biologyMutations of the PALB2 gene lead to a number of hereditary cancer-predisposing syndromes, including Fanconi anemia and hereditary breast and ovarian cancer syndrome. Originally identified as a core DNA repair factor, emerging evidence now implicates PALB2 in cell cycle checkpoint control, DNA replication, oxidative stress regulation and transcription, highlighting the multi-functionality of the tumor suppressor. Notably, mechanistically how its expanding repertoire of functions are orchestrated remains ...postprin
Stem cell transplantation therapies in Parkinson’s disease
2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
An E2-guided E3 Screen Identifies the RNF17-UBE2U Pair as Regulator of the Radiosensitivity, Immunodeficiency, Dysmorphic Features, and Learning Difficulties (RIDDLE) Syndrome Protein RNF168
Protein ubiquitination has emerged as a pivotal regulatory reaction that promotes cellular responses to DNA damage. With a goal to delineate the DNA damage signal transduction cascade, we systematically analyzed the human E2 ubiquitin- and ubiquitin-like-conjugating enzymes for their ability to mobilize the DNA damage marker 53BP1 onto ionizing radiation-induced DNA double strand breaks. An RNAi-based screen identified UBE2U as a candidate regulator of chromatin responses at double strand breaks. Further mining of the UBE2U interactome uncovered its cognate E3 RNF17 as a novel factor that, via the radiosensitivity, immunodeficiency, dysmorphic features, and learning difficulties (RIDDLE) syndrome protein RNF168, enforces DNA damage responses. Our screen allowed us to uncover new players in the mammalian DNA damage response and highlights the instrumental roles of ubiquitin machineries in promoting cell responses to genotoxic stress.published_or_final_versio
ADRC-based model predictive current control for PMSMs fed by three-phase four-switch inverters
© 2016 IEEE.A novel automatic disturbances rejection control (ADRC)-based model predictive current control (MPCC) strategy is developed for permanent magnet synchronous motors (PMSMs) fed by three-phase four-switch inverters, an after-fault-topology for fault-tolerant three-phase six-switch inverters. The mathematical model of a PMSM fed by a three-phase four-switch inverter is built firstly. Then the ADRC and MPCC are respectively designed, with the former being used to realize disturbance estimation and disturbance compensation while the latter being used to reduce stator current ripple and improve the quality of the torque and speed control. The resultant ADRC-based MPCC PMSM fed by an unhealthy inverter has fault-tolerant effective with dynamical performance very close to an ADRC-based MPCC PMSM fed by a healthy inverter. On the other hand, compared with PI-based MPCC PMSM fed by an unhealthy inverter, it possesses better dynamical response behavior and stronger robustness as well as smaller THD index of three-phase stator current in the presence of variation of load torque. The simulation results validate the feasibility and effectiveness of the proposed scheme
Angle-Resolved X-Ray Circular and Magnetic Circular Dichroisms: Definitions and Applications
We introduce definitions of angle-resolved x-ray circular dichroism (ARXCD) and magnetic x-ray circular dichroism (ARMXCD). As defined, the much larger effect of circular dichroism (ARXCD) is separated from the smaller magnetic (ARMXCD) effect. In all materials, ARXCD is zero along mirror planes while nonzero elsewhere. ARMXCD is nonzero only in magnetic materials. The measurement and analysis of ARMXCD allow element specific surface magnetism and surface structure as well as their inter-relationship to be studied as functions of the outgoing electron\u27s direction
The Research of Infrared Thermal Image Diagnostic Model for Building External Wall Tiles
This study focuses on a deterioration diagnostic standard and inspection time for external wall tiles. The study was carried out using a tap tone test, followed by fast Fourier transform and pattern recognition to analyse the tapping results. Based on the test results, the study recommends that for frequencies between 200 and 800 Hz on the spectrogram, it can be deduced that a cavity is present in the tiles. The study was carried out using infrared thermal imaging record to deterioration and normal tile position. This study observed temperature changes per hour, it is obvious temperature difference with deterioration tiles and normal tiles between 09: 00-11: 00 (East), 10:00-14:00 (West), 10:00-12:00 (South) and 11:00-13:00 (North), the study was calculated that the average temperature difference of 1.0 degrees. This study suggests that the best experimental inspection time is 09: 00-14:00. Exclude the impact of external factors, if the temperature difference more than 1.0 degrees, it can be deduced that a cavity is present in the tiles, and this can be used as basis for determining tile deterioration
Analysis on Thermal Hazard of Foam Decoration Materials
The occurrence and spread of fire often result from the flammables in interior decoration materials, which mostly contain fireproof foam to avoid fire damage. In this study, the foams with reportedly fire resistance, such as general foam, PU foam, melamine foam, and rubber foam, are compared via thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analysis to build a thermal parameter database of decoration materials of fireproof foams and provide green building materials, technologies, and fire preventive measures to the industry or consumers
Trinitrophenol Reactive T-Cell Hybridomas Recognize Antigens That Require Antigen Processing
Protein antigens must be taken up, processed, and displayed on the surface of antigen-presenting cells in association with major histocompatibility complex molecules before they can be recognized by T cells. Whether recognition of the haptens used to study allergic contact hypersensitivity in murine models similarly requires processing has not been determined. We analyzed whether presentation of trinitrophenol to trinitrophenol reactive T-cell hybridomas requires antigen processing by studying the effects of inhibitors of antigen processing and presentation on tile ability of a syngeneic B-cell tumor (A20) to present trinitrophenol to a series of interleukin-2 producing, trinitrophenol specific, major histocompatibility complex class II-restricted T-cell hybridomas.The ability of trinitrophenol modified A20 cells to stimulate the hybridomas was completely inhibited by rnonoclonal, anti-trinitrophenol, or anti-Ia antibodies and was significantly reduced by paraformaldehyde fixation immediately after trinitrophenol modification. Trinitrophenol-modified A20 cultured at 37°C for 2h prior to fixation was significantly more effective at stimulating the hybridomas than trinitrophenol-modified A20 to present trinitrophenol was inhibited by chloroquine. Paraformaldehyde fixation and chloroquine treatment had similar effects on the ability of trinitrophenol modified lymph node dendritic cells to stimulate the trinitrophenol specific hybridomas. Paraformaldehyde fixation and chloroquine treatment had similar effects on the ability of A20 cells to present ovalbumin to ovalbumin-specific hybridomas as they had on the ability of trinitrophenol modified A20 cells to present trinitrophenol to the trinitrophenol specific hybridomas. One of seven T-cell hybridomas responded to trinitrophenol modified ovalbumin but not other trinitrophenol modified proteins. These results suggest that, at least in part, T cells in the contact hypersensitivity response to trinitrophenol recognize antigens that require processing and that trinitrophenol modified proteins can be recognized
Role of domain walls in the abnormal photovoltaic effect in BiFeO3
Recently, the anomalous photovoltaic (PV) effect in BiFeO3 (BFO) thin
films, which resulted in open circuit voltages (V-oc) considerably
larger than the band gap of the material, has generated a revival of the
entire field of photoferroelectrics. Here, via temperature-dependent PV
studies, we prove that the bulk photovoltaic (BPV) effect, which has
been studied in the past for many non-centrosymmetric materials, is at
the origin of the anomalous PV effect in BFO films. Moreover, we show
that irrespective of the measurement geometry, V-oc as high as 50V can
be achieved by controlling the conductivity of domain walls (DW). We
also show that photoconductivity of the DW is markedly higher than in
the bulk of BFO
5-Hydroxy-3,4′,6,7-tetramethoxyflavone
The title compound, C19H18O7 [systematic name 5-hydroxy-3,6,7-trimethoxy-2-(4-methoxyphenyl)-4H-1-benzopyran-4-one], is a flavonoid which was isolated from the traditional Chinese medicine Laggera alata. The benzene ring of the benzopyranone unit forms dihedral angles of 1.72 (3) and 37.39 (5)° with the pyran ring and the substituent benzene ring, respectively. The molecular conformation is stabilized by an intramolecular phenol O—H⋯Oketone hydrogen bond
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