193 research outputs found

    Dissociation and Internal Excitation of Molecular Nitrogen Due to N + N2 Collisions Using Direct Molecular Simulation

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    In this work we present a molecular level study of N2+N collisions, focusing on excitation of internal energy modes and non-equilibrium dissociation. The computation technique used here is the direct molecular simulation (DMS) method and the molecular interactions have been modeled using an abinitio potential energy surface (PES) developed at NASA's Ames Research Center. We carried out vibrational excitation calculations between 5000K and 30000K and found that the characteristic vibrational excitation time for the N + N2 process was an order of magnitude lower than that predicted by the Millikan and White correlation. It is observed that during vibrational excitation the high energy tail of the vibrational energy distribution gets over populated first and the lower energy levels get populated as the system evolves. It is found that the non-equilibrium dissociation rate coefficients for the N + N2 process are larger than those for the N2 + N2 process. This is attributed to the non-equilibrium vibrational energy distributions for the N + N2 process being less depleted than that for the N2 +N2 process. For an isothermal simulation we find that the probability of dissociation goes as 1/T(sub tr) for molecules with internal energy (epsilon(sub int)) less than approximately 9.9eV, while for molecules with epsilon (sub int) greater than 9.9eV the dissociation probability was weakly dependent on translational temperature of the system. We compared non-equilibrium dissociation rate coefficients and characteristic vibrational excitation times obtained by using the ab-initio PES developed at NASA's Ames Research Center to those obtained by using an ab-initio PES developed at the University of Minnesota. Good agreement was found between the macroscopic properties and molecular level description of the system obtained by using the two PESs

    Design optimization of deflection caused after release of multilayer structural membrane of Symmetric Toggle Switch

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    This paper presents the optimization in deflection caused by the inbuilt stress generated in mechanical or movable membrane of Symmetric Toggle RF MEMS Switch (STS). The movable membrane of STS was initially fabricated with two different materials, i.e. Chrome and Gold. The simulated deflection at 70°C was 11.9 μm, and experimental deflection was 11-12 μm. We present a study of inbuilt deflection reduction in multimetal movable layers without change in actuation voltage of the switch. The design study was initially carried out on cantilevers and then on structural membrane of STS. STS with proposed multilayer of Cr-Au-Au-Ti-Au has a simulated deflection of 0.56 μm at 70°C. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2212

    An unusual case of three concomitant primary solid cancers with unique histopathological characteristics

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    INTRODUCTION AND IMPORTANCE: Struma Ovarii is a rare type of monodermal teratoma with at least 50 % of its mass being thyroid tissue. They make up &lt;1 % of all ovarian tumours and 3 to 5 % of all ovarian teratomas. These tumours are usually benign but malignant transformation is seen in &lt;5 % of cases.CASE PRESENTATION: We present the case of a 45-year-old lady with three synchronous primary cancers on a background of Struma Ovarii; primary lung adenocarcinoma, papillary thyroid carcinoma and ovarian teratoma. Over the course of 18 months, this lady underwent full pelvic clearance of malignant Struma Ovarii and lymph nodes, total thyroidectomy, and an anatomical lung resection.CLINICAL DISCUSSION: This case represents an incredibly rare condition of Struma Ovarii for which there is no firm management consensus. Furthermore, the uniqueness of three separate primaries has to the best of our knowledge not previously been reported in the literature.CONCLUSION: This reinforces the notion that in select patients, radical management with curative intent is entirely possible but requires complete multi-disciplinary and multi-modal sub-specialty collaboration.</p

    An unusual case of three concomitant primary solid cancers with unique histopathological characteristics

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    INTRODUCTION AND IMPORTANCE: Struma Ovarii is a rare type of monodermal teratoma with at least 50 % of its mass being thyroid tissue. They make up &lt;1 % of all ovarian tumours and 3 to 5 % of all ovarian teratomas. These tumours are usually benign but malignant transformation is seen in &lt;5 % of cases.CASE PRESENTATION: We present the case of a 45-year-old lady with three synchronous primary cancers on a background of Struma Ovarii; primary lung adenocarcinoma, papillary thyroid carcinoma and ovarian teratoma. Over the course of 18 months, this lady underwent full pelvic clearance of malignant Struma Ovarii and lymph nodes, total thyroidectomy, and an anatomical lung resection.CLINICAL DISCUSSION: This case represents an incredibly rare condition of Struma Ovarii for which there is no firm management consensus. Furthermore, the uniqueness of three separate primaries has to the best of our knowledge not previously been reported in the literature.CONCLUSION: This reinforces the notion that in select patients, radical management with curative intent is entirely possible but requires complete multi-disciplinary and multi-modal sub-specialty collaboration.</p

    M2 macrophages exhibit higher sensitivity to oxLDL-induced lipotoxicity than other monocyte/macrophage subtypes

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    <p>Abstract</p> <p>Background</p> <p>In obesity, phenotypic switches occur in macrophage populations such that the predominantly M2-polarised anti-inflammatory state seen in lean individuals changes to a predominantly M1-polarised pro-inflammatory state in those who are obese. However, the mechanisms by which these phenotypic shifts occur have not yet been fully elucidated.</p> <p>Results</p> <p>The effects of oxLDL (1-40 μg/ml; 24 h) on several parameters relevant to the Unfolded Protein Response (UPR)-mediated lipotoxic effects of oxLDL (disruption of ER Ca<sup>2+ </sup>handling; activation of the UPR transcription factor XBP-1; upregulation of the UPR target genes BiP and CHOP; apoptosis; cell viability) were investigated in human primary monocyte-derived macrophages, and also in monocyte-macrophages derived from the THP-1 monocytic cell line. A consistent pattern was observed: M2-polarised macrophages were more sensitive to the lipotoxic effects of oxLDL than either non-polarised macrophages or non-differentiated monocytic cells. Specifically, M2-polarised macrophages were the only cell type to undergo significantly increased apoptosis (Primary cells: 1.23 ± 0.01 basal; THP-1-derived: 1.97 ± 0.12 basal; <it>P </it>< 0.05 in both cases) and decreased cell viability (Primary cells: 0.79 ± 0.04 basal; THP-1-derived: 0.67 ± 0.02 basal; <it>P </it>< 0.05 in both cases) when exposed to oxLDL levels similar to those seen in overweight individuals (ie. 1 μg/ml).</p> <p>Conclusions</p> <p>We propose that the enhanced susceptibility of M2-polarised macrophages to lipotoxicity seen in the present <it>in vitro </it>study could, over time, contribute to the phenotypic shift seen in obese individuals <it>in vivo</it>. This is because a higher degree of oxLDL-induced lipotoxic cell death within M2 macrophages could contribute to a decrease in numbers of M2 cells, and thus a relative increase in proportion of non-M2 cells, within macrophage populations. Given the pro-inflammatory characteristics of a predominantly M1-polarised state, the data presented here may constitute a useful contribution to our understanding of the origin of the pro-inflammatory nature of obesity, and of the pathogenesis of obesity-associated inflammatory disorders such as Type 2 Diabetes and atherosclerosis.</p

    Lung cancer resection in patients with underlying usual interstitial pneumonia:a meta-analysis

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    Objective Patients with lung cancer with underlying idiopathic pulmonary fibrosis and usual interstitial pneumonia (UIP) pattern on CT represent a very high-risk group in terms of postoperative UIP acute exacerbations (AEs) and in-hospital mortality. We sought to investigate the outcomes in these patients.Methods We carried out a meta-analysis, searching four international databases from 1 January 1947 to 27 April 2022, for studies in any language reporting on the acute postoperative outcomes of patients with lung cancer undergoing surgical resection with underlying UIP (the primary outcome). Random effects meta-analyses (DerSimonian and Laird) were conducted. We analysed the difference in incidence of postoperative AE as well as the difference in long-term overall survival among subpopulations. These were stratified by the extent of surgical resection, with meta-regression testing (uniivariate and multivariate) according to the stage of disease, operative decision making and country of origin. This study was registered with PROSPERO (CRD42022319245).Results The overall incidence of AE of UIP postoperatively from 10 studies (2202 patients) was 14.6% (random effects model, 95% CI 9.8 to 20.1, I2=74%). Sublobar resection was significantly associated with a reduced odds of postoperative AE (OR 0.521 (fixed effects model), 95% CI 0.339 to 0.803, p=0.0031, I2=0%). The extent of resection was not significantly associated with overall survival following lung cancer resection in UIP patients (HR for sublobar resection 0.978 (random effects model), 95% CI 0.521 to 1.833, p=0.9351, I2=71%).Conclusions With appropriate implementation of perioperative measures such as screening for high-risk cases, appropriate use of steroids, antifibrotics and employing sublobar resection in select cases, the risk of local recurrence versus in-hospital mortality from AEUIP can be balanced and long-term survival can be achieved in a super-selected group of patients. Further investigation in the form of a randomised study is warranted

    Diagnostic Performance of the PalmScan VF2000 Virtual Reality Visual Field Analyzer for Identification and Classification of Glaucoma

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    Purpose: To evaluate the diagnostic test properties of the Palm Scan VF2000® Virtual Reality Visual Field Analyzer for diagnosis and classification of the severity of glaucoma. Methods: This study was a prospective cross-sectional analysis of 166 eyes from 97 participants. All of them were examined by the Humphrey® Field Analyzer (used as the gold standard) and the Palm Scan VF 2000® Virtual Reality Visual Field Analyzer on the same day by the same examiner. We estimated the kappa statistic (including 95% confidence interval [CI]) as a measure of agreement between these two methods. The diagnostic test properties were assessed using sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Results: The sensitivity, specificity, PPV, and NPV for the Virtual Reality Visual Field Analyzer for the classification of individuals as glaucoma/non-glaucoma was 100%. The general agreement for the classification of glaucoma between these two instruments was 0.63 (95% CI: 0.56–0.78). The agreement for mild glaucoma was 0.76 (95% CI: 0.61–0.92), for moderate glaucoma was 0.37 (0.14–0.60), and for severe glaucoma was 0.70 (95% CI: 0.55–0.85). About 28% of moderate glaucoma cases were misclassified as mild and 17% were misclassified as severe by the virtual reality visual field analyzer. Furthermore, 20% of severe cases were misclassified as moderate by this instrument. Conclusion: The instrument is 100% sensitive and specific in detection of glaucoma. However, among patients with glaucoma, there is a relatively high proportion of misclassification of severity of glaucoma. Thus, although useful for screening of glaucoma, it cannot replace the Humphrey® Field Analyzer for the clinical management in its current form

    Characterizing the Decision Process in Setting Corn and Soybean Seeding Rates

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    Selecting optimal corn and soybean seeding rates are difficult decisions to make. A survey of Ohio and Michigan farm operators finds that, although generally keen to learn from others, they tend to emphasize their own experience over outside information sources. Soybean growers declare university and extension recommendations as more important than do corn growers. In response to direct queries and in free comments, growers place more emphasis on understanding the agronomic and technological problems at hand than on adjusting to the market environment. Given the decision environment, we argue that these responses are reasonable

    Ion irradiation of Fe-Fe oxide core-shell nanocluster films: Effect of interface on stability of magnetic properties

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    A cluster deposition method was used to produce films of loosely aggregated nanoclusters (NC) of Fe core-Fe3O4 shell or fully oxidized Fe3O4. Films of these NC on Si(100) or MgO(100)/Fe3O4(100) were irradiated to 10^16 Si2+/cm2 near room temperature using an ion accelerator. Ion irradiation creates structural change in the NC film with corresponding chemical and magnetic changes which depend on the initial oxidation state of the cluster. Films were characterized using magnetometry (hysteresis, first order reversal curves), microscopy (transmission electron, helium ion), and x-ray diffraction. In all cases, the particle sizes increased due to ion irradiation, and when a core of Fe is present, irradiation reduces the oxide shells to lower valent Fe species. These results show that ion irradiated behavior of the nanocluster films depends strongly on the initial nanostructure and chemistry, but in general saturation magnetization decreases slightly.Comment: 25 pages, 4 tables, 6 figure

    Phage Ligands for Identification of Mesenchymal-Like Breast Cancer Cells and Cancer-Associated Fibroblasts

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    Epithelial to mesenchymal transition (EMT) is believed to be crucial for primary tumors to escape their original residence and invade and metastasize. To properly define EMT, there is a need for ligands that can identify this phenomenon in tumor tissue and invivo. A phage-display selection screening was performed to select novel binding phage peptides for identification of EMT in breast cancer. Epithelial breast cancer cell line, MCF-7 was transformed to mesenchymal phenotype by TGF-β treatment and was used for selection. Breast fibroblasts were used for subtractive depletion and breast cancer metastatic cell lines MDA-MB-231, T47D-shNMI were used for specificity assay. The binding peptides were identified, and their binding capacities were confirmed by phage capture assay, phage-based ELISA, immunofluorescence microscopy. The phage peptide bearing the 7-amino acid sequence, LGLRGSL, demonstrated selective binding to EMT phenotypic cells (MCF-7/TGF-β and MDA-MB-231) as compared to epithelial subtype, MCF-7, T47D and breast fibroblasts (Hs578T). The selected phage was also able to identify metastatic breast cancer tumor in breast cancer tissue microarray (TMA). These studies suggest that the selected phage peptide LGLRGSL identified by phage-display library, showed significant ability to bind to mesenchymal-like breast cancer cells/ tissues and can serve as a novel probe/ligand for metastatic breast cancer diagnostic and imaging
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