24 research outputs found
A molten salt test loop for component and instrumentation testing
Molten salt is an effective coolant for a wide range of applications, including nuclear reactors, concentrated solar power, and other high temperature industrial heat transfer processes. The technical readiness level of components and instrumentation for high-temperature molten salt applications needs improvement for molten salt to be more widely adopted. A molten salt test loop was designed, built, and commissioned as a test bed to address these issues. The molten salt test loop at Abilene Christian University was built out of 316 stainless steel with a forced flow centrifugal-type pump, and was instrumented for remote operation. A low-temperature molten nitrate salt was used in this system, which was designed to operate at temperatures up to 300 ◦C and flow rates up to 90 liters per minute.
This paper describes the loop design, computational fluid dynamics modeling, construction, and commissioning details. An outline of the data acquisition and control systems is presented. Salt samples were taken before and after introduction into the loop, and melting points were measured both before and after salt circulation. Performance of the system is discussed as well as improvements required for higher temperature loops envisioned for the future
PH modulation method to detect ligand-receptor binding
The present disclosure relates to detecting receptor-ligand binding by measuring local pH modulation using a pH-sensitive fluorophore.U
A Simple Method of Hydrogen Insertion in Transition Metal Oxides to Obtain Bronzes
Reaction of , and with alcohols or glycols is shown to yield hydrogen bronzes of the oxides. Cubic and tetragonal , as well as have been prepared by this method
PH modulation method to detect ligand-receptor binding
The present disclosure relates to detecting receptor-ligand binding by measuring local pH modulation using a pH-sensitive fluorophore.U
Fluorescence modulation sensing of positively and negatively charged proteins on lipid bilayers
Pediatric Deep Brain Stimulation Using Awake Recording and Stimulation for Target Selection in an Inpatient Neuromodulation Monitoring Unit
Deep brain stimulation (DBS) for secondary (acquired, combined) dystonia does not reach the high degree of efficacy achieved in primary (genetic, isolated) dystonia. We hypothesize that this may be due to variability in the underlying injury, so that different children may require placement of electrodes in different regions of basal ganglia and thalamus. We describe a new targeting procedure in which temporary depth electrodes are placed at multiple possible targets in basal ganglia and thalamus, and probing for efficacy is performed using test stimulation and recording while children remain for one week in an inpatient Neuromodulation Monitoring Unit (NMU). Nine Children with severe secondary dystonia underwent the NMU targeting procedure. In all cases, 4 electrodes were implanted. We compared the results to 6 children who had previously had 4 electrodes implanted using standard intraoperative microelectrode targeting techniques. Results showed a significant benefit, with 80% of children with NMU targeting achieving greater than 5-point improvement on the Burke–Fahn–Marsden Dystonia Rating Scale (BFMDRS), compared with 50% of children using intraoperative targeting. NMU targeting improved BFMDRS by an average of 17.1 whereas intraoperative targeting improved by an average of 10.3. These preliminary results support the use of test stimulation and recording in a Neuromodulation Monitoring Unit (NMU) as a new technique with the potential to improve outcomes following DBS in children with secondary (acquired) dystonia. A larger sample size will be needed to confirm these results
The nucleosome acidic patch is required <i>in vivo</i> for the DDR in human cells.
<p>(<b>A and B</b>) <i>In vivo</i> expression of the acidic patch interacting portion of LANA (1–32 amino acids) reduces 53BP1, but not MDC1, IRIF (ionizing radiation induced-foci). Human U2OS cells were transfected with GFP-LANA (1–32a.a.) followed by 2 Gy IR-treatment. Cells were analyzed by IF with the indicated antibodies 2 h post-IR. Representative IF images are shown. Nuclear DNA was visualized by Hoechst 33342 staining. Quantification of A is shown in B. 53BP1 and MDC1 IRIF were counted and graphed for cells (−) or (+) GFP-LANA (1–32a.a.). N = 3, >100 cells analyzed/experiment, error bars = SEM. Student's t-tests (paired) were performed and results indicated. *** = p-value<0.001, ns = not significant (i.e. p-value>0.05). (<b>C</b>) IF analysis of DDR factor foci formation after IR treatment in GFP-LANA and mutant GFP-LANA-8LRS10 expressing cells. Cells were treated with 2 Gy IR and processed for IF 2 h post-IR. IF analysis was performed as in A. (<b>D</b>) Quantification of 53BP1 IRIF from C. Graph represents values obtained from two independent experiments where foci from >100 cells were scored for GFP-LANA-8LRS10 expressing cells and non-GFP expressing cells. Error bars = SEM. Statistical analysis was performed as in B. (E) GFP-LANA (1–32a.a.) impairs recruitment of 53BP1 to laser damage. U2OS cells were transfected with GFP-LANA (1–32a.a.) followed by laser micro-irradiation. Cells were fixed and stained with antibodies as indicated 2 h post-laser damage. Quantification of 53BP1 and MDC1 laser lines were obtained from >50 damaged cells from two independent experiments. Error bars = SEM.</p
Nucleosome acidic patch promotes RNF168-dependent DDR signaling and inhibition of DNA resection in G1.
<p>(<b>A and B</b>) RIF1 and BRCA1 IRIF are impaired in GFP-LANA (1–32a.a.) expressing cells. Experiments were performed as in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004178#pgen-1004178-g005" target="_blank">Figure 5A</a>. Representative images are shown. CyclinA negative and high/low LANA expressing cells are indicated in the merged image. Note: CyclinA marks S/G2 cells. (<b>C and D</b>) Quantification of RIF1 and BRCA1/CyclinA-positive IRIF from A and B. Graphs represent values obtained from two independent experiments where foci from >100 cells were quantified. Error bars = SEM. (<b>E</b>) GFP-LANA (1–32a.a.) expressing cells exhibit DNA end-resection as detected by RPA accumulation at laser damage in G1 (CyclinA-negative) cells. Experiments were performed as in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004178#pgen-1004178-g005" target="_blank">Figure 5E</a> with indicated antibodies after 4 h post micro-irradiation. (<b>F</b>) RPA32 laser lines in CyclinA-negative cells without or with GFP-LANA (1–32a.a.) expression are indicated by yellow and green dotted lines respectively. Enlarged images from each category are shown. All cells have been laser damaged. (<b>G</b>) Quantification of F and G from either WT GFP-LANA (1–32a.a.) or mutant (Mut) GFP-LANA-8LRS10 expressing cells. Laser damaged CylclinA negative cells positive for LANA expression were scored for RPA laser line formation. Graph represents data obtained from >50 cells from two independent experiments. Error bars = SEM.</p
RING1B/BMI1- and RNF168-dependent ubiquitination of H2AX/H2A requires the nucleosome acidic patch <i>in vitro</i>.
<p>(<b>A</b>) Schematic for <i>in vitro</i> reconstitution of nucleosome core particles (NCPs). (<b>B</b>) Bacterially expressed and purified human histones. Histones were expressed, purified and reconstituted as described in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004178#s3" target="_blank">methods</a>. (<b>C</b>) Analysis of <i>in vitro</i> reconstituted NCPs. The 147 bp 601 DNA fragment was analyzed alone or after NCP reconstitution. DNA ladder indicates size (bp). (<b>D and E</b>) RING1B/BMI1 and RNF168 readily ubiquitinate H2AX within WT NCPs but not NCPs containing a mutation in the acidic patch (H2AX-E92A). In vitro Ub assays (4 h) were performed as described in <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1004178#s3" target="_blank">methods</a>. (<b>F</b>) RNF168 ubiquitinates WT H2AX and H2AX-E92A similarly when assayed in the context of free histones. Assays were performed as in E except with free histones and reactions were performed overnight. (<b>G and H</b>) RING1B/BMI1 and RNF168 readily ubiquitinate H2A within WT NCPs but not NCPs containing a mutation in the acidic patch (H2A-E92A). Experiments were performed as in D and E using H2A. (<b>I</b>) RNF168 ubiquitinates free WT H2A and H2A-E92A similarly. Experiments performed as in F.</p