TOC COMPLEX FORMATION: AN INVESTIGATION OF THE INTERACTIONS GOVERNING TOC COMPLEX COMPOSITION AND ASSEMBLY

Chloroplast-destined preproteins are translated in the cytosol, and posttranslationally targeted to and translocated across the double envelope membrane of the chloroplast by the coordinated activities of two translocon complexes: the Translocons at the Outer and Inner envelope membrane of the Chloroplast (TOC and TIC, respectively). In the model organism Arabidopsis thaliana the core TOC components include two families of GTPase receptors: TOC159 (atToc159, -132, and -120) and TOC34 (atToc33 and -34). These receptor families are hypothesized to assemble into distinct complexes and recognize transit peptides present on the N-terminus of chloroplast-destined preproteins. The GTPase domains of the TOC159 and TOC34 family members are hypothesized to interact in such a way that structurally and functionally distinct TOC complexes are formed. These distinct complexes are thought to have specificity for different subsets of preproteins. Chloroplasts must differentiate between different subsets of proteins because they are needed in different amounts during various stages of chloroplast biogenesis. This investigation examines the propensity for atToc33 and atToc34 to associate with atToc159 or atToc132, how these interactions affect TOC complex formation, as well as what protein domains are conferring this preference. In vitro competitive chloroplast targeting assays, in which the GTPase domains of atToc33 or atToc34 are used as competitors for targeting of atToc159 or atToc132 to chloroplasts, and in vitro solidphase binding assays, in which the GTPase domains of atToc33 or atToc34 are used as bait to test interactions with prey atToc159 or atToc132 are used to characterize these interactions. In order to study the influence of the highly divergent A-domain, these associations are also being investigated using A-domain deletion mutants, atToc159GM and atToc132GM as well as A-domain swapped mutants 159A132GM and 132A159GM. This investigation has revealed that the mechanisms governing TOC GTPase interactions in Arabidopsis may be dictated by the A-domain of atToc132 and the G-domain of atToc159, thereby giving insight into how key TOC components are assembled into distinct TOC complexes at the chloroplast surface. Distinct complexes are responsible for the critical identification and import of different subsets of preproteins, all of which are necessary for plant growth and development

Supporting research studies to booster flight control problems Final report

Asymptotic stability and response of nonlinear system

Evidence that a Panel of Neurodegeneration Biomarkers Predicts Vasospasm, Infarction, and Outcome in Aneurysmal Subarachnoid Hemorrhage

Biomarkers for neurodegeneration could be early prognostic measures of brain damage and dysfunction in aneurysmal subarachnoid hemorrhage (aSAH) with clinical and medical applications. Recently, we developed a new panel of neurodegeneration biomarkers, and report here on their relationships with pathophysiological complications and outcomes following severe aSAH. Fourteen patients provided serial cerebrospinal fluid samples for up to 10 days and were evaluated by ultrasonography, angiography, magnetic resonance imaging, and clinical examination. Functional outcomes were assessed at hospital discharge and 6–9 months thereafter. Eight biomarkers for acute brain damage were quantified: calpain-derived α-spectrin N- and C-terminal fragments (CCSntf and CCSctf), hypophosphorylated neurofilament H

Dose volume histogram‐based optimization of image reconstruction parameters for quantitative 90Y‐PET imaging

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147185/1/mp13269.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147185/2/mp13269_am.pd

Teknologi Dalam Pendidikan: Membantu Siswa Beradaptasi Dengan Revolusi Industri 4.0

The development of the industrial revolution demanded various changes in every activity, including in the field of education. Through technological developments in the learning process will be able to help students to face these challenges. This study aims to analyze the implementation of technology in education to help students face the challenges of the industrial revolution 4.0. This research is a descriptive qualitative research collecting data from literature study. The results of this study found that technology has a significant role in the world of education, especially in the era of the industrial revolution 4.0. Through the use of technology, students gain relevant skills and knowledge in the future. Then through the use of technology too, the creativity and innovation of students can be developed, as well as helping to establish social relations that are broader and also inclusive. Of course, in implementing this, careful planning is needed, so that the technolog

90Y PET/CT quantitative accuracy and image quality

Purpose: To optimize 90Y-PET/CT image reconstruction for quantitative accuracy and optimal image quality.Methods: PET/CT scans of a NEMA IEC phantom (3GBq 90YCl2, sphere uptake ratio of ~7) were acquired on 4 GE (BGO:DSTE, DST & LYSO:DRX, D690) and 1 Siemens (LSO:mCT) scanners in 3D list mode with 30 min/bed; replayed to 20, 15, 10 min/bed. Iterative reconstruction parameters explored were SUB × IT (3 – 80) and post-reconstruction filters: transaxial: 5 – 25 mm cutoff & z-axis (GE only): std vs. heavy. The effects of PSF modeling and TOF correction were evaluated for D690 and mCT. VOIs were drawn inside spheres and in adjacent background regions. The accuracy of sphere activity concentration (AC in kBq/mL) and contrast to noise ratio (CNR) was calculated as function of SUB × IT. Reconstructed PET images were also evaluated qualitatively for sphere detectability and artifacts.Results: AC converged to 70 – 90% accuracy for 37 mm sphere and further degraded for smaller spheres. Spheres at max CNR might not reach AC convergence yet. Smaller spheres have slower convergence but reach CNR max together with other spheres. Scan duration did not strongly affect sphere convergence but shorter scans increased noise and reduced detectability; 13 mm spheres were not visible going from 30 to 15 min/bed. Heavy z-axis (GE) and transaxial filter with 10 – 15 mm cutoff helped suppress noise and increase sphere detectability at the expense of accuracy. Images with PSF+TOF corrections had higher sphere detectability and converged faster. Hot cluster artifacts 5 – 7 times the background were seen in some cases with SUB × IT near convergence and lower filtration.Conclusion: Accurate 90Y AC was not achieved even at convergence and noise is a major concern. 90YPET/CT reconstruction parameters are different than those for 18F and benefit substantially from PSF+TOF corrections. Optimum image quality and accurate AC may not be simultaneously achievable.----------------------------------------Cite this article as: Siman W, Mawlawi O, Kappadath SC. 90Y PET/CT quantitative accuracy and image quality. Int J Cancer Ther Oncol 2014; 2(2):020235. DOI: 10.14319/ijcto.0202.3

Thermal-hydraulic analysis of the liquid mercury target for the national spallation neutron source

The National Spallation Neutron Source (NSNS) is a high-energy, accelerator-based spallation neutron source being designed by a multi-laboratory team led by Oak Ridge National Laboratory (ORNL) to achieve very high fluxes of neutrons for scientific experiments. The NSNS is proposed to have a 1 MW beam of high-energy ({approximately}1 GeV) protons upgradable to 5 MW and operating at 60 Hz with a pulse duration of 0.5 {mu}s. Peak steady-state power density in the target is about 640 MW/m{sup 3} for 1 MW, whereas the pulse instantaneous peak power density is as high as 22,000 GW/m{sup 3}. The local peak temperature rise for a single pulse over it`s time-averaged value is only 6{degrees}C, but the rate of this temperature rise during the pulse is extremely fast ({approximately}12 million {degrees}C/s). In addition to the resulting thermal shock and materials compatibility concerns, key feasibility issues for the target are related to its thermal-hydraulic performance. These include proper flow distribution, flow reversals and stagnation zones, possible {open_quotes}hot spots{close_quotes}, cooling of the beam {open_quotes}window{close_quotes}, and the challenge of mitigating the effects of thermal shock through possible injection of helium bubbles. An analytic approach was used on the PC spreadsheet EXCEL to evaluate target design options and to determine the global T/H parameters in the current concept. The general computational fluid dynamics (CFD) code CFX was used to simulate the detailed time-averaged two-dimensional thermal and flow distributions in the liquid mercury. In this paper, an overview of the project and the results of this preliminary work are presented. Heat transfer characteristics of liquid mercury under wetting and non-wetting conditions are discussed, and future directions of the program in T/H analysis and R&D are outlined

Calpain mediates proteolysis of the voltage-gated sodium channel alpha-subunit

Alterations in the expression, molecular composition, and localization of voltage-gated sodium channels play major roles in a broad range of neurological disorders. Recent evidence identifies sodium channel proteolysis as a key early event after ischemia and traumatic brain injury, further expanding the role of the sodium channel in neurological diseases. In this study, we investigate the protease responsible for proteolytic cleavage of voltage-gated sodium channels (NaChs). NaCh proteolysis occurs after protease activation in rat brain homogenates, pharmacological disruption of ionic homeostasis in cortical cultures, and mechanical injury using an in vitro model of traumatic brain injury. Proteolysis requires Ca2+ and calpain activation but is not influenced by caspase-3 or cathepsin inhibition. Proteolysis results in loss of the full-length {alpha}-subunits, and the creation of fragments comprising all domains of the channel that retain interaction even after proteolysis. Cell surface biotinylation after mechanical injury indicates that proteolyzed NaChs remain in the membrane before noticeable evidence of neuronal death, providing a mechanism for altered action potential initiation, propagation, and downstream signaling events after Ca2+ elevation

Proteomics: in pursuit of effective traumatic brain injury therapeutics

Effective traumatic brain injury (TBI) therapeutics remain stubbornly elusive. Efforts in the field have been challenged by the heterogeneity of clinical TBI, with greater complexity among underlying molecular phenotypes than initially conceived. Future research must confront the multitude of factors comprising this heterogeneity, representing a big data challenge befitting the coming informatics age. Proteomics is poised to serve a central role in prescriptive therapeutic development, as it offers an efficient endpoint within which to assess post-TBI biochemistry. We examine rationale for multifactor TBI proteomic studies and the particular importance of temporal profiling in defining biochemical sequences and guiding therapeutic development. Lastly, we offer perspective on repurposing biofluid proteomics to develop theragnostic assays with which to prescribe, monitor and assess pharmaceutics for improved translation and outcome for TBI patients