Alien Registration- Foster, L M Weyland (Portland, Cumberland County)

https://digitalmaine.com/alien_docs/23905/thumbnail.jp

Nanometer scale electronic reconstruction at the interface between LaVO3 and LaVO4

Electrons at interfaces, driven to minimize their free energy, are distributed differently than in bulk. This can be dramatic at interfaces involving heterovalent compounds. Here we profile an abrupt interface between V 3d2 LaVO3 and V 3d0 LaVO4 using electron energy loss spectroscopy. Although no bulk phase of LaVOx with a V 3d1 configuration exists, we find a nanometer-wide region of V 3d1 at the LaVO3/LaVO4 interface, rather than a mixture of V 3d0 and V 3d2. The two-dimensional sheet of 3d1 electrons is a prototypical electronic reconstruction at an interface between competing ground states.Comment: 14 pages, 5 figure

Stabilization of Polar Nano Regions in Pb-free ferroelectrics

Formation of polar nano regions through solid-solution additions are known to enhance significantly the functional properties of ferroelectric materials. Despite considerable progress in characterizing the microscopic behavior of polar nano regions, understanding their real-space atomic structure and dynamics of formation remains a considerable challenge. Here, using the method of dynamic pair distribution function, we provide direct insights into the role of solid-solution additions towards the stabilization of polar nano regions in the Pb-free ferroelectric of Ba(Zr,Ti)O3. It is shown that for an optimum level of substitution of Ti by larger Zr ions, the dynamics of atomic displacements for ferroelectric polarization are slowed sufficiently, which leads to increased local correlation among dipoles below THz frequencies. The dynamic pair distribution function technique demonstrates unique capability to obtain insights into locally correlated atomic dynamics in disordered materials, including new Pb-free ferroelectrics, which is necessary to understand and control their functional properties

Argon does not affect cerebral circulation or metabolism in male humans

Objective: Accumulating data have recently underlined argońs neuroprotective potential. However, to the best of our knowledge, no data are available on the cerebrovascular effects of argon (Ar) in humans. We hypothesized that argon inhalation does not affect mean blood flow velocity of the middle cerebral artery (Vmca), cerebral flow index (FI), zero flow pressure (ZFP), effective cerebral perfusion pressure (CPPe), resistance area product (RAP) and the arterio-jugular venous content differences of oxygen (AJVDO2), glucose (AJVDG), and lactate (AJVDL) in anesthetized patients. Materials and methods: In a secondary analysis of an earlier controlled cross-over trial we compared parameters of the cerebral circulation under 15 minutes exposure to 70%Ar/30%O2versus 70%N2/30%O2in 29 male patients under fentanyl-midazolam anaesthesia before coronary surgery. Vmca was measured by transcranial Doppler sonography. ZFP and RAP were estimated by linear regression analysis of pressure-flow velocity relationships of the middle cerebral artery. CPPe was calculated as the difference between mean arterial pressure and ZFP. AJVDO2, AJVDG and AJVDL were calculated as the differences in contents between arterial and jugular-venous blood of oxygen, glucose, and lactate. Statistical analysis was done by t-tests and ANOVA. Results: Mechanical ventilation with 70% Ar did not cause any significant changes in mean arterial pressure, Vmca, FI, ZFP, CPPe, RAP, AJVDO2, AJVDG, and AJVDL. Discussion: Short-term inhalation of 70% Ar does not affect global cerebral circulation or metabolism in male humans under general anaesthesia

Development and characterization of immuno-nanocarriers targeting the cancer stem cell marker AC133

In the context of targeted therapy, we addressed the possibility of developing a drug delivery nanocarrier capable to specifically reach cancer cells that express the most prominent marker associated with cancer stem cell (CSC) phenotype, AC133. For this purpose, 100 nm lipid nanocapsules (LNCs) were functionalized with a monoclonal antibody (mAb) directed against AC133 according to two distinct methods: firstly, post-insertion within 100 nm LNCs of a lipid poly(ethylene glycol) functionalized with reactive-sulfhydryl maleimide groups (DSPE-PEG2000-maleimide) followed by thiolated mAb coupling, and, secondly, creation of a thiolated lipo-immunoglobulin between DSPE-PEG2000-maleimide and AC133, then post-inserted within LNCs. Due to the reduced number of purification steps, lower amounts of DSPE-PEG2000-maleimide that were necessary as well as lower number of free maleimide functions present onto the surface of immuno-LNC, the second method was found to be more appropriate. Thus, 126 nm AC133-LNC with a zeta potential of −22 mV while keeping a narrow distribution were developed. Use of the IgG1κ isotype control-immunoglobulins produced similar control IgG1-LNCs. Micro-Bradford colorimetric assay indicated a fixation of about 40 immunoglobulins per LNC. Use of human Caco-2 cells that constitutively express AC133 (Caco-2-AC133high) allowed addressing the behavior of the newly functionalized immuno-LNCs. siRNA knockown strategy permitted to obtain Caco-2-AC133low for comparison. Immunofluorescence-combined flow cytometry analysis demonstrated that the epitope-recognition function of AC133 antibody was preserved when present on immuno-LNCs. Although grafting of immunoglobulins onto the surface of LNCs repressed their internalization within Caco-2 cells as evaluated by flow cytometry, AC133-specific cellular binding was obtained with AC133-LNC as assessed by computer-assisted fluorescence microscopy. In conclusion, interest of AC133-LNCs as niche carriers is discussed toward the development of CSC targeted chemo- or radio-nanomedicines

Accuracy and Prognostic Role of NCCT-ASPECTS Depend on Time from Acute Stroke Symptom-onset for both Human and Machine-learning Based Evaluation.

PURPOSE We hypothesize that the detectability of early ischemic changes on non-contrast computed tomography (NCCT) is limited in hyperacute stroke for both human and machine-learning based evaluation. In short onset-time-to-imaging (OTI), the CT angiography collateral status may identify fast stroke progressors better than early ischemic changes quantified by ASPECTS. METHODS In this retrospective, monocenter study, CT angiography collaterals (Tan score) and ASPECTS on acute and follow-up NCCT were evaluated by two raters. Additionally, a machine-learning algorithm evaluated the ASPECTS scale on the NCCT (e-ASPECTS). In this study 136 patients from 03/2015 to 12/2019 with occlusion of the main segment of the middle cerebral artery, with a defined symptom-onset-time and successful mechanical thrombectomy (MT) (modified treatment in cerebral infarction score mTICI = 2c or 3) were evaluated. RESULTS Agreement between acute and follow-up ASPECTS were found to depend on OTI for both human (Intraclass correlation coefficient, ICC = 0.43 for OTI < 100 min, ICC = 0.57 for OTI 100-200 min, ICC = 0.81 for OTI ≥ 200 min) and machine-learning based ASPECTS evaluation (ICC = 0.24 for OTI < 100 min, ICC = 0.61 for OTI 100-200 min, ICC = 0.63 for OTI ≥ 200 min). The same applied to the interrater reliability. Collaterals were predictors of a favorable clinical outcome especially in hyperacute stroke with OTI < 100 min (collaterals: OR = 5.67 CI = 2.38-17.8, p < 0.001; ASPECTS: OR = 1.44, CI = 0.91-2.65, p = 0.15) while ASPECTS was in prolonged OTI ≥ 200 min (collaterals OR = 4.21,CI = 1.36-21.9, p = 0.03; ASPECTS: OR = 2.85, CI = 1.46-7.46, p = 0.01). CONCLUSION The accuracy and reliability of NCCT-ASPECTS are time dependent for both human and machine-learning based evaluation, indicating reduced detectability of fast stroke progressors by NCCT. In hyperacute stroke, collateral status from CT-angiography may help for a better prognosis on clinical outcome and explain the occurrence of futile recanalization