An efficient iterative CBCT reconstruction approach using gradient projection sparse reconstruction algorithm

The purpose of this study is to develop a fast and convergence proofed CBCT reconstruction framework based on the compressed sensing theory which not only lowers the imaging dose but also is computationally practicable in the busy clinic. We simplified the original mathematical formulation of gradient projection for sparse reconstruction (GPSR) to minimize the number of forward and backward projections for line search processes at each iteration. GPSR based algorithms generally showed improved image quality over the FDK algorithm especially when only a small number of projection data were available. When there were only 40 projections from 360 degree fan beam geometry, the quality of GPSR based algorithms surpassed FDK algorithm within 10 iterations in terms of the mean squared relative error. Our proposed GPSR algorithm converged as fast as the conventional GPSR with a reasonably low computational complexity. The outcomes demonstrate that the proposed GPSR algorithm is attractive for use in real time applications such as on-line IGRT

Conversion of Sox2-dependent Merkel cell carcinoma to a differentiated neuron-like phenotype by T antigen inhibition

Viral cancers show oncogene addiction to viral oncoproteins, which are required for survival and proliferation of the dedifferentiated cancer cell. Human Merkel cell carcinomas (MCCs) that harbor a clonally integrated Merkel cell polyomavirus (MCV) genome have low mutation burden and require viral T antigen expression for tumor growth. Here, we showed that MCV+ MCC cells cocultured with keratinocytes undergo neuron-like differentiation with neurite outgrowth, secretory vesicle accumulation, and the generation of sodium-dependent action potentials, hallmarks of a neuronal cell lineage. Cocultured keratinocytes are essential for induction of the neuronal phenotype. Keratinocyte-conditioned medium was insufficient to induce this phenotype. Single-cell RNA sequencing revealed that T antigen knockdown inhibited cell cycle gene expression and reduced expression of key Merkel cell lineage/MCC marker genes, including HES6, SOX2, ATOH1, and KRT20. Of these, T antigen knockdown directly inhibited Sox2 and Atoh1 expression. MCV large T up-regulated Sox2 through its retinoblastoma protein-inhibition domain, which in turn activated Atoh1 expression. The knockdown of Sox2 in MCV+ MCCs mimicked T antigen knockdown by inducing MCC cell growth arrest and neuron-like differentiation. These results show Sox2-dependent conversion of an undifferentiated, aggressive cancer cell to a differentiated neuron-like phenotype and suggest that the ontology of MCC arises from a neuronal cell precursor

Adoption of Health Information Technology Among US Nursing Facilities

Objectives: Nursing facilities have lagged behind in the adoption interoperable health information technology (i.e. technologies that allow the sharing and use of electronic patient information between different information systems). The objective of this study was to estimate the nationwide prevalence of electronic health record (EHR) adoption among nursing facilities and to identify the factors associated with adoption. Design: Cross-sectional survey. Setting & participants: We surveyed members of the Society for Post-Acute & Long-Term Care Medicine (AMDA) about their organizations’ health information technology usage and characteristics. Measurements: Using questions adopted from existing instruments, the survey measured nursing home’s EHR adoption, the ability to send, receive, search and integrate electronic information, as well as barriers to usage. Additionally, we linked survey responses to public use secondary data sources to construct measurements for eight determinants known to be associated with organizational adoption: innovativeness, functional differentiation, role specialization, administrative intensity, professionalism, complexity, technical knowledge resources and slack resources. A series of regression models estimated the association between potential determinants and technology adoption. Results: 84% of nursing facilities reported using an EHR. After controlling for all other factors, respondents who characterized their organization as more innovative had more than 6 times the odds (adjusted odds ratio = 6.39; 95%CI = 2.69, 15.21) of adopting an EHR. Organization innovativeness was also associated with an increased odds of being able to send, integrate, and search for electronic information. The most commonly identified barrier to sharing clinical information among nursing facilities with an EHR was a reported absence of interoperability (57%). Conclusions/Implications: An organizational culture that fosters innovation and awareness campaigns by professional societies may facilitate further adoption and effective use of technology. This will be increasingly important as policymakers continue to emphasize the use of EHRs and interoperability to improve the quality of care in nursing facilities

The Otterbein Miscellany - May 1972

https://digitalcommons.otterbein.edu/miscellany/1016/thumbnail.jp

Smartphone Household Wireless Electroencephalogram Hat

Rudimentary brain machine interface has existed for the gaming industry. Here, we propose a wireless, real-time, and smartphone-based electroencephalogram (EEG) system for homecare applications. The system uses high-density dry electrodes and compressive sensing strategies to overcome conflicting requirements between spatial electrode density, temporal resolution, and spatiotemporal throughput rate. Spatial sparseness is addressed by close proximity between active electrodes and desired source locations and using an adaptive selection of N active among 10N passive electrodes to form m-organized random linear combinations of readouts, m≪N≪10N. Temporal sparseness is addressed via parallel frame differences in hardware. During the design phase, we took tethered laboratory EEG dataset and applied fuzzy logic to compute (a) spatiotemporal average of larger magnitude EEG data centers in 0.3 second intervals and (b) inside brainwave sources by Independent Component Analysis blind deconvolution without knowing the impulse response function. Our main contributions are the fidelity of quality wireless EEG data compared to original tethered data and the speed of compressive image recovery. We have compared our recovery of ill-posed inverse data against results using Block Sparse Code. Future work includes development of strategies to filter unwanted artifact from high-density EEGs (i.e., facial muscle-related events and wireless environmental electromagnetic interferences)

Southern Ocean mesocyclones and polar lows from manually tracked satellite mosaics

A new reference dataset of mesocyclone activity over the Southern Ocean has been developed from the manual analysis of high resolution infrared satellite mosaics for winter 2004. Of the total 1735 mesocyclones which were identified and analyzed about three quarters were classified as being ‘polar lows’ (i.e. intense systems; see Rasmussen and Turner 2003). The dataset includes mesocyclone track, size, associated cloud vortex type and background synoptic conditions. Maxima in track density were observed over the Bellingshausen Sea and around East Antarctica and are highly correlated with cyclogenesis regions. A comparison against QuikSCAT and reanalyses wind characteristics shows that the reanalyses, while capturing mesocyclone events, tend to considerably underestimate their wind speed (by up to 10 ms-1). This mesocyclone dataset is available as a reference for further analysis of mesocyclones and for the evaluation and development of cyclone-tracking algorithms

An acid-stable laccase from sclerotium rolfsii with potential for wool dye decolourization

The plant pathogen basidiomycete S. rolfsii secretes two laccases (SRL1 and SRL2) with molecular weights of 55 and 86 kDa, respectively. Laccase production was shown to be inducible by the addition of 2,5-xylidine to the cultural media. After treatment with a combination of chitinase and -1,3-glucanase, two different laccases were isolated from the sclerotia depending on the stage of sclerotia development. The more prominent laccase, SRL1, was purified and found to decolourize the industrially important wool azo dye Diamond Black PV 200 without the addition of redox mediators. The enzyme (pI 5.2) was active in the acidic pH range, showing an optimal activity at pH 2.4, with ABTS as substrate. The optimum temperature for activity was determined to be 62 ◦C. Enzyme stability studies revealed that SRL1 was notably stable at 18 ◦C and pH 4.5, retaining almost full activity after a week. Oxidation of tyrosine was not detectable under the reaction conditions but the enzyme did oxidize a variety of the usual laccase substrates. SRL1 was strongly inhibited by sodium azide and fluoride. Dye solutions decolourized with the immobilized laccase were successfully used for redyeing.(undefined

Ultrafast terahertz-field-driven ionic response in ferroelectric BaTiO3

The dynamical processes associated with electric field manipulation of the polarization in a ferroelectric remain largely unknown but fundamentally determine the speed and functionality of ferroelectric materials and devices. Here we apply subpicosecond duration, single-cycle terahertz pulses as an ultrafast electric field bias to prototypical BaTiO[subscript 3] ferroelectric thin films with the atomic-scale response probed by femtosecond x-ray-scattering techniques. We show that electric fields applied perpendicular to the ferroelectric polarization drive large-amplitude displacements of the titanium atoms along the ferroelectric polarization axis, comparable to that of the built-in displacements associated with the intrinsic polarization and incoherent across unit cells. This effect is associated with a dynamic rotation of the ferroelectric polarization switching on and then off on picosecond time scales. These transient polarization modulations are followed by long-lived vibrational heating effects driven by resonant excitation of the ferroelectric soft mode, as reflected in changes in the c-axis tetragonality. The ultrafast structural characterization described here enables a direct comparison with first-principles-based molecular-dynamics simulations, with good agreement obtained