Proprietary Method Research Articles

Effect of Cathode Proton Conductivity on PGM-free PEM Fuel Cell Performance

The most promising alternative to Platinum Group Metals (PGMs) Oxygen Reduction Reaction (ORR) catalysts for proton exchange membrane fuel cell (PEMFC) applications is a class of electrocatalysts consisting of atomically dispersed transition metals (Fe and Mn) in a matrix of carbon and nitrogen, so called M-N-C materials [1]. Currently, the emerging novel M-N-C materials demonstrated 30% of PGM catalyst activity [1]. Performance of PGM-free electrocatalysts can be improved by increasing density of M-Nx sites or optimizing their accessibility through proper integration into the triple phase catalyst layer in a membrane electrode assembly (MEA). Since overall MEA’s performance depends on properties of all its components: membrane, electrodes and gas diffusion layers (GDL), it is important to understand impact of these materials on PGM-free fuel cell operation. In this work we report effects of membrane thickness on performance of PGM-free PEMFCs using various electrochemical methods and modelling.The commercial, PGM-free electrocatalyst manufactured by Pajarito Powder and marketed as PMF-011904 was used in the present study. Catalyst coated membranes with active area of 23 cm2 were manufactured by IRD Fuel Cell by their proprietary digital printing method. For this work we used membranes with thickness of 15 (LYT0008), 25 (N211), 125 (N115) and 175 (N117) μm. The cathode PGM-free catalyst loading was 6.0 mg cm-2, while anode employed Pt/C catalyst with loading of 0.2 mgPt cm-2. Freudenberg H23C8 GDLs were applied for both electrodes. Electrochemical evaluation of PGM–free MEAs was performed using a custom test station, designed at the HNEI and characterized by dynamic response time <0.1 s. The anode and cathode were fed with H2 and O2 respectively, at constant flow rates of 0.5 slpm at 100% relative humidity and 150 kPa absolute backpressure for both electrodes, and the cell temperature was 80°C.Fig. 1 a) shows a representative SEM image of the MEA cross-section. The cathode thickness was found to be 140-160 μm for all samples. The IV data clearly showed that an increase in the membrane thickness led to an increase of HFR and caused poor performance (Fig. 1 b). The highest performance was achieved for MEAs with thin membranes 15 and 25 μm. At the same time application of thick membrane allowed us to reach the highest ocv values 0.979 V (175 μm) vs 0.929 V (15 μm). The impedance data were analyzed using physics-based model which includes proton and oxygen transport in the cathode layer [2]. The results demonstrated a rapid decay of proton conductivity from 15-18 to 5-10 mS cm-1 at current densities higher than 100 mA cm-2. Possible mechanism of the observed decay can be attributed to dissolution of Fe-N-C centers and formation of Fe3+ cations which reduce ionomer conductivity by screening SO3- groups [3-4].Due to relatively low proton conductivity and large electrode thickness, the ORR rate is strongly non–uniform through the cathode depth. Our estimates showed that this non-uniformity leads to 2 K overheat of the catalyst layer at the membrane surface. The overheat could induce pressure gradient, pushing liquid water out of the electrode and clearing void pores for gaseous transport of oxygen. This mechanism might explain explosive growth of the cathode oxygen diffusivity (5-7⋅10-3 cm2 s-1). Detailed analyses of the PGM-free PEMFC performance and its correlation with AC-impedance results will be presented and discussed.AcknowledgmentsWe gratefully acknowledge funding from ONR (N00014-19-1-2159) and DOE EERE (DE-EE0008419). The authors are thankful to T. Carvalho for assisting with SEM.Reference1. S.T. Thompson, A.R. Wilson, P. Zelenay, D.J. Myers, K.L. More, K.C. Neyerlin, D. Papageorgopoulos, Solid State Ionics 319, 68-69 (2018).2. A. Kulikovsky, J. Electroanal. Chem. 669, 28-34 (2012).3. T. Reshetenko, G. Randolf, M. Odgaard, B. Zulevi, A. Serov, A. Kulikovsky, J. Electrochem. Soc. 167, 084501 (2020).4. T. Reshetenko, A. Serov, A. Kulikovsky, P. Atanassov, J. Electrochem. Soc. 166, F653-F660 (2019). Figure 1

The Business Transformation Framework and Enterprise Architecture Framework for Managers in Business Innovation

This journal article proposes a cross-business domain applied holistic mathematical model (AHMM) that is the result of a lifetime long research on business transformations, applied mathematics, software modelling, business engineering, financial analysis, and global enterprise architecture. This ultimate research is based on an authentic and proprietary mixed research method that is supported by an underlining mainly qualitative holistic reasoning model module. The proposed AHMM formalism attempts to mimic some functions of the human brain, which uses empirical processes that are mainly based on the beam-search, like heuristic decision-making process. The AHMM can be used to implement a decision-making system or an expert system that can integrate in the enterprise's business, information and communication technology environments. The AHMM uses a behaviour driven development environment or a natural language environment that can be easily adopted by the project's development teams. The AHMM offers a high level implementation environment that can be used by any team member without any prior computer sciences qualification. The AHMM can be used also to model enterprise architecture (EA) blueprints, business transformation projects, or knowledge management systems; it is supported by many real-life cases of various business domains. The uniqueness of this research is that the AHMM promotes a holistic unbundling process, the alignment of various EA standards and transformation strategies to support business transformation projects.

Cryopreserved, Thin, Laser-Etched Osteochondral Allograft maintains the functional components of articular cartilage after 2\u2009years of storage

BackgroundDespite improvements in treatment options and techniques, articular cartilage repair continues to be a challenge for orthopedic surgeons. This study provides data to support that the 2-year Cryopreserved, Thin, Laser-Etched Osteochondral Allograft (T-LE Allograft) embodies the necessary viable cells, protein signaling, and extracellular matrix (ECM) scaffold found in fresh cartilage in order to facilitate a positive clinical outcome for cartilage defect replacement and repair.MethodsViability testing was performed by digestion of the graft, and cells were counted using a trypan blue assay. Growth factor and ECM protein content was quantified using biochemical assays. A fixation model was introduced to assess tissue outgrowth capability and cellular metabolic activity in vitro. Histological and immunofluorescence staining were employed to confirm tissue architecture, cellular outgrowth, and presence of ECM. The effects of the T-LE Allograft to signal bone marrow-derived mesenchymal stem cell (BM-MSC) migration and chondrogenic differentiation were evaluated using in vitro co-culture assays. Immunogenicity testing was completed using flow cytometry analysis of cells obtained from digested T-LE Allografts and fresh articular cartilage.ResultsAverage viability of the T-LE Allograft post-thaw was found to be 94.97 ± 3.38%, compared to 98.83 ± 0.43% for fresh articular cartilage. Explant studies from the in vitro fixation model confirmed the long-term viability and proliferative capacity of these chondrocytes. Growth factor and ECM proteins were quantified for the T-LE Allograft revealing similar profiles to fresh articular cartilage. Cellular signaling of the T-LE Allograft and fresh articular cartilage both exhibited similar outcomes in co-culture for migration and differentiation of BM-MSCs. Flow cytometry testing confirmed the T-LE Allograft is immune-privileged as it is negative for immunogenic markers and positive for chondrogenic markers.ConclusionsUsing our novel, proprietary cryopreservation method, the T-LE Allograft, retains excellent cellular viability, with native-like growth factor and ECM composition of healthy cartilage after 2 years of storage at − 80 °C. The successful cryopreservation of the T-LE Allograft alleviates the limited availably of conventionally used fresh osteochondral allograft (OCA), by providing a readily available and simple to use allograft solution. The results presented in this paper supports clinical data that the T-LE Allograft can be a successful option for repairing chondral defects.

Biaxial flexural strength, crystalline structure, and grain size of new commercially available zirconia-based ceramics for dental appliances produced using a new slip-casting method

ObjectiveThe aim of this study was to evaluate the biaxial flexural strength, the crystalline structure, and the grain size of zirconia-based ceramics produced using a new slip-casting method. Materials and methodsYttria-stabilized Tetragonal Zirconia Polycrystal (Y-TZP) and Alumina Toughened Zirconia (ATZ) ceramics were purchased from different manufactures. For the experimental group, ceramics produced using a patent pending slip-casting method (Slurry, Decema GmbH) was used. Slurry ceramics (n = 42) with a diameter of 14 ± 0.2 mm were produced by a proprietary colloidal shaping process, sintered, and subsequently polished with a lapping process using 15 μm diamond particles to a thickness of 1.2 ± 0.2 mm. For the control group, ceramics produced using the hot isostatic pressure method (HIP, Metoxit AG) were used. HIP ceramics discs (n = 42) with a diameter of 15.5 ± 0.02 mm were produced by classical HIP method and subsequently machined to a thickness of 1.99 ± 0.04 mm 32 discs of each ceramic were submitted to a biaxial flexural strength test using an universal testing machine at a crosshead speed of 0.5 mm/min. Statistical analyses using two-way ANOVA and Weibull distribution were performed. 2 discs of each ceramic were analyzed using X-ray diffraction for grain crystalline phase quantification. 2 discs of each ceramic were thermally etched and scanning electron microscopy images were obtained for grain size analysis (ISO 13383–1:2012). 6 discs of each ceramic were used for density measurement using the Archimedes’ method. ResultsFor both ATZ and Y-TZP ceramics, the biaxial flexural strength and the characteristic strength of ceramics produced using the Slurry method were significantly higher than ones of the ceramic produced using HIP. The structure analysis confirmed the superiority of the Slurry ceramics which had only 1.2% tetragonal phase compared to 11–16% for the HIP ceramics. Grain size distributions covered a wide range 50–800 nm; the ZrO2 grains of the Slurry ceramics were significantly smaller than the ones of the control ceramics, while the Al2O3 grain distributions were not affected by the manufacturing process. The manufacturing process had no influence on the density of both materials. ConclusionsThe Slurry method using a new proprietary slip-casting method to produce Y-TZP and ATZ dental ceramics presented higher biaxial flexural strength, less monoclinic phase and smaller ZrO2 grains.

Comparison of segmental lean tissue mass in individuals with spinal cord injury measured by dual energy X-ray absorptiometry and predicted by bioimpedance spectroscopy.

Observational. To compare two methods for predicting segmental (arms, legs, trunk) lean tissue mass (LTM: non-bone fat-free mass) from bioimpedance spectroscopy (BIS) against LTM measured from dual energy X-ray absorptiometry (DXA) in individuals with acute spinal cord injury (SCI). Austin Health Victorian Spinal Cord Service, Victoria, Australia. Fourteen participants (two female), within 8 weeks of traumatic SCI had BIS measured following an overnight fast and within 24 h of DXA scanning. Total body fat-free mass (FFM, body weight minus fat mass) and segmental LTM were predicted from BIS using manufacturer's proprietary software and a previously established SCI-specific prediction method. Appendicular LTM (ALM) was calculated from the sum of the LTM of the arms and legs. Agreement and strength of relationships with DXA for predicted LTM measures using both approaches were assessed using Lin's concordance coefficient and limits of agreementanalysis (LOA). The BIS proprietary method performed better than the SCI-specific prediction method in predicting DXA LTM, demonstrating substantial concordance for total body FFM (rc = 0.80), ALM (rc = 0.78), arm (rc = 0.76) and leg LTM (rc = 0.65) and a smaller bias and LOA for ALM (+0.8 vs. -3.4 kg; LOA -4.9-6.4 vs. -11.9-5.1 kg), arm (+0.02 vs. -0.3 kg; LOA -1.1-1.1 kg vs. -2.2-1.6 kg) and leg (+0.4 vs. -1.4 kg; LOA -2.0-2.8 vs. -5.6-2.8) LTM. BIS can be used to accurately predict total body FFM, segmental LTM and ALM in individuals with acute SCI.

An Orthotropic Elastic-Plastic Constitutive Model for Masonry Walls.

The use of a continuum structural model for the analysis of masonry structures in the plane stress state is discussed in this paper. Attention is paid to orthotropic masonry at the material level and validation of the model after its implementation in a proprietary finite element method (FEM) system via user-supplied subroutine. The constitutive relations are established in the framework of the mathematical elastoplasticity theory of small displacements and deformations. Based on the orthotropic failure criterion that was originally proposed by Hoffman in the spatial stress state, the model includes a generalization of the criterion in the plane stress. As it is the case for isotropic quasi-brittle materials, different yield surfaces are considered for tension and compression, which are both of Hoffman type.

A REDESIGN OF THE PROTEX TO HARVEST FREE OXYGEN SPECIES APPEARS TO IMPROVE OVERALL SEMEN PARAMETERS

Previous research from this laboratory has demonstrated that semen quality, both physiological and biochemical, can be improved via a simple redesign of the semen collection cup. The redesign termed the Device for Improved Semen Collection (DISC – trade name ProteX), maintains a stable environment during and after collection, preventing cell shock and preserving cell function. However, the original design did nothing to prevent DNA fragmentation. Recently the system underwent a redesign incorporating a proprietary method to harvest free oxygen radicals, an identified cause of DNA fragmentation.

Abstract 1630: FceR1g negative NK-cells (g-NK) enhance antibody-dependent cellular cytotoxicity and in vivo efficacy of therapeutic monoclonal antibodies against hematologic malignanices

Abstract Monoclonal antibodies (mAbs) are a central component of hematologic malignancy therapy; however, not all patients initially respond to these agents and resistance is a major clinical issue. A major mechanism of action for these mAbs in vivo is NK cell antibody-dependent cellular cytotoxicity (ADCC). Recent studies led to the discovery of a novel subset of human NK cells that lack expression of FceR1g (“g-NK cells”) and have a multi-fold increase in ADCC activity after CD16 crosslinking. Here, we validate the potency of g-NKs as an off-the shelf cellular immunotherapy to enhance the efficacy of therapeutic mAbs. g-NK cells were enriched and expanded using a proprietary method from CMV-positive blood donors selected for high levels of circulating g-NKs. For ADCC cytotoxicity assays, expanded NK cells were sorted by flow cytometry into populations of “conventional” NK cells (cNK), adaptive (NKG2C+) NK cells, and g-NK cells. After sorting, NK-cells were co-cultured 4 hr at 37° C with Raji or MM.1S target cells (1e4 cells) at varying NK-cell:target cell ratios. For in vivo persistence studies a single dose of 1e7 g-NK or cNK cells was injected into NOD scid gamma (NSG) mice. For in vivo efficacy studies with rituximab (RIT), NSG mice were inoculated with 5e5 luciferase-labeled Raji lymphoma cells and dosed weekly with 15e6 g-NK cells +/-200 ug RIT or vehicle. For in vivo efficacy studies with daratumumab (DARA) and elotuzumab (ELO), NSG mice were inoculated with 1e6 luciferase-labeled MM.1S cells and dosed every 6d with expanded g-NKs (20e6), resting cNKs (3e5, equivalent to physiological levels of NK cells/kg in humans, and +/- 10 ug DARA or 10 ug ELO. In all studies, mice received IL-15 intraperitoneally every 3 days. Our expansion method was able to expand g-NKs from selected CMV-seropositive donors ~800-fold (n=8). By flow cytometry we found an increase in the percentage of g-NK from 28% of NK cells at input to 82% post-expansion. In vitro ADCC assays demonstrated that g-NKs enhanced cytotoxicity of RIT to Raji cells (70% at 1:1 E:T) when compared to both NKG2C+ NKs (29%) and cNKs (27%) (p&amp;lt;0.001). Notably, we saw similar ADCC of g-NK cells whether used fresh or thawed after viable freezing (70% vs. 63%, p=0.71). In addition, g-NK cells enhanced cytotoxicity of DARA and ELO to MM.1S cells (58% and 54% at 1:1 E:T) when compared to cNK (14% and 12% at 1:1 E:T) (p&amp;lt;0.001). We confirmed in NSG mice that g-NK persistence was markedly improved (&amp;gt;90%) over cNKs in blood at multiple time points (p&amp;lt;0.001), and spleen at Day 22 (p&amp;lt;0.001). Efficacy studies using Raji cells showed the combination of g-NK and RIT led to a &amp;gt;90% reduction in tumor burden versus RIT alone (p&amp;lt;0.001). Evaluation of expanded g-NKs in a disseminated orthotopic xenograft model of multiple myeloma found a dramatic reduction (&amp;gt;70%) in tumor burden with DARA+g-NK vs. DARA alone or DARA+cNK (p&amp;lt;0.001). Similar results were found with ELO. Here we demonstrate that adoptive transfer of expanded g-NK cells markedly enhances anti-tumor ADCC of therapeutic mAbs in several preclinical models. Importantly, because adoptive transfer of NK-cells in humans does not result in severe graft-versus-host disease, we propose that this long-lived, highly potent NK-cell therapy could be administered in an “off-the-shelf” manner to supercharge mAb efficacy. Citation Format: Austin Basil Bigley, Nadia H. Agha, Shanae Spade, Gaetano Dipierro, Ronald Martell, Byron C. Hann, Nina Shah, Arun P. Wiita. FceR1g negative NK-cells (g-NK) enhance antibody-dependent cellular cytotoxicity and in vivo efficacy of therapeutic monoclonal antibodies against hematologic malignanices [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1630.

Evaluation of Asphalt Concrete Airport Pavement Conditions Based on the Airfield Pavement Condition Index (APCI) in Scope of Flight Safety

Airoport infrastructure development requires care to maintain it in proper technical condition. Due to this, airport pavements should be constantly monitored, and, above all, correctly managed. High-level airport pavement management requires access to reliable information about their current technical condition as well as proper forecasting of this condition in the future. Obtaining good quality information about the technical condition of airport pavement should be based on a proven methodology, taking into account the introduced quality management system. The authors propose a method of technical pavement condition assessment based on the Airfield Pavement Condition Index (APCI), taking into account not only the results of the surface deterioration inventory, but also repair overviews, load bearing capacity, evenness and roughness of the surface, as well as the surface tensile bond strength. The method was developed during long-term work financed by the Ministry of Science and Higher Education. At the beginning of the article, the authors focus on reviewing the currently available methods of assessing the technical condition of the pavement. Then they briefly present the most popular surface assessment method based on the PCI indicator. Afterwards, a proprietary asphalt pavement assessment method based on the APCI indicator is proposed and an example of how to use the method is presented. Finally, they discuss the results and summarize the work done, and present further directions of work.

Non-small cell lung cancer: Analysis using mass cytometry and next generation sequencing reveals new opportunities for the development of personalized therapies.

e21026 Background: Comprehensive molecular profiling and the use of biomarkers as companion diagnostics have transformed precision medicine for cancer patients. To identify patient-specific tumor microenvironment and biomarker profiles, we assessed the accuracy of our deconvolution algorithm in identifying cellular compositions from whole exome (WES) and whole transcriptome (RNA-seq) sequencing of solid tumors compared with cell populations identified by Mass Cytometry by Time of Flight (CyTOF) in surgically resected tissue from non-small cell lung cancer (NSCLC) patients. Methods: Resected NSCLC tissue was divided for RNA-seq and WES of whole tissue (n = 9) and for generating tissue single cell suspensions through mechanical dissociation and enzymatic digestion (n = 11). Bulk RNA-seq and CyTOF were performed on all cell suspensions. Cellular phenotypes were identified using clustering algorithms in CyTOF and predicted from bulk RNA-seq using our proprietary computational method. Results: Cellular composition reconstructed from RNA-seq correlated with the composition detected by CyTOF (R2= 0.922, n = 7) from cell suspensions. To recover the cell percentage from bulk RNA-seq, a machine learning framework was trained on the cell compendia comprising 7,117 unique cell type RNA-seq profiles. A two-stage hierarchical learning procedure generated a gradient boosting Light GBM model that included training on artificial RNA-seq mixtures of different cell types. With this method, we found that stromal and malignant cells were depleted during single cell suspension preparation, resulting in statistically significant differences in the tumor cell composition reconstructed from solid tissue and single cell suspensions. Immune cell types namely T cells and macrophages were similarly represented in both the bulk tumor tissue and matched single cell suspensions. Transcriptomics revealed a subgroup of patients whose tumors were B-cell-enriched, which was validated in other NSCLC cohorts and was associated with greater CD4+ and CD8+ T cell infiltration and improved clinical outcomes. Conclusions: Since preparation of single cell suspensions leads to the loss of several cellular components, RNA-seq of tumor bulk tissue better describes the molecular and cellular properties of the tumor microenvironment. The combination of RNA-seq and WES of tumor tissue provides a comprehensive profile of cellular composition, suggesting that this combination is ideal for precision medicine applications.

Quantum and classical machine learning for the classification of non-small-cell lung cancer patients

The ability to accurately classify disease subtypes is of vital importance, especially in oncology where this capability could have a life saving impact. Here we report a classification between two subtypes of non-small cell lung cancer, namely Adenocarcinoma versus Squamous cell carcinoma. The data consists of approximately 20,000 gene expression values for each of 104 patients. The data was curated from Kuner (Geo lung cancer data set—gse10245, 2009, http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE10245 ) and Golumbic (Geo lung cancer data set—gse18842, 2010, http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE18842 ). We used a combination of classical and quantum machine learning models to successfully classify these patients. We utilized feature selection methods based on univariate statistics in addition to XGBoost (Guestrin and Chen in Xgboost: a scalable tree boosting system, 2007, https://dl.acm.org/citation.cfm?id=1273596 ). A novel and proprietary data representation method developed by one of the authors called QCrush was also used as it was designed to incorporate a maximal amount of information under the size constraints of the D-Wave quantum annealing computer. The machine learning was performed by a quantum Boltzmann machine. This paper will report our results, the various classical methods, and the quantum machine learning approach we utilized.

Неправильный мёд соседского права

The present research featured the legal nature of the negatory action as one of the common ways to protect the rights of a real estate owner. The article focuses on the ground of this action and the fact in proof in property rights protection cases not related to dispossession. The authors drew a parallel between the negatory action and the prohibitory action which prohibits offensive activities or hazards of injury infliction. In spite of the fact that the prohibitory action used to be associated with the nugatory one, they demand different kinds of actual statutory regulation and law enforcement. The authors agree that the lawsuit on the prohibition of activities, as provided for by Article 1065 of the Civil Code of the Russian Federation, stems from a tort, and is not a proprietary method of defense of rights. In the Russian civil law, the law of neighboring tenements remains underdeveloped, as does the defense of rights of the real estate owner from their neighbors. The authors believe that it is wrong to justify the negatory action by administrative law as this violates the rules for overcoming conflicts of legal regulation, shifting the burden of proof, and deviating from the standards of adversarial and equal rights of the parties in the civil process.

Topical Application of Exosomes Derived from Human Umbilical Cord Mesenchymal Stem Cells in Combination with Sponge Spicules for Treatment of Photoaging.

PurposeThe topical application of exosomes secreted by mesenchymal stem cells (MSC-Exos) on the skin is a very new and interesting topic in the medical field. In this study, we aimed to investigate whether marine sponge Haliclona sp. spicules (SHSs) could effectively enhance the skin delivery of human umbilical cord-derived MSC-Exos (hucMSC-Exos), and further evaluate the topical application of hucMSC-Exos combined with SHSs in rejuvenating photoaged mouse skin.Materials and MethodsSHSs were isolated from the explants of sponge Haliclona sp. with our proprietary method, and hucMSC-Exos were prepared from the conditioned medium of hucMSCs using ultracentrifugation. The effects of SHSs on the skin penetration of fluorescently labeled hucMSC-Exos were determined using confocal microscopy in vitro (porcine skin) and in vivo (mouse skin). The therapeutic effects of hucMSC-Exos coupled with SHSs against UV-induced photoaging in mice were assessed by using microwrinkles analysis, pathohistological examination and real-time RT-PCR. We also tested the skin irritation caused by the combination of hucMSC-Exos and SHSs in guinea pigs.ResultsIn vitro results showed that hucMSC-Exos could not readily penetrate through porcine skin by themselves. However, SHSs increased the skin absorption of exosomes by a factor of 5.87 through creating microchannels. Similar penetration enhancement of hucMSC-Exos was observed after SHSs treatment in mice. The combined use of hucMSC-Exos and SHSs showed significant anti-photoaging effects in mice, including reducing microwrinkles, alleviating histopathological changes, and promoting the expression of extracellular matrix constituents, whereas hucMSC-Exos alone produced considerably weaker effects. Skin irritation test showed that the combination of hucMSC-Exos and SHSs caused slight irritation, and the skin recovered shortly.ConclusionSHSs provide a safe and effective way to enhance the skin delivery of MSC-Exos. Moreover, the combination of MSC-Exos and SHSs may be of much use in the treatment of photoaging.

Optimal Multi-Stage Arrhythmia Classification Approach

Arrhythmia constitutes a problem with the rate or rhythm of the heartbeat, and an early diagnosis is essential for the timely inception of successful treatment. We have jointly optimized the entire multi-stage arrhythmia classification scheme based on 12-lead surface ECGs that attains the accuracy performance level of professional cardiologists. The new approach is comprised of a three-step noise reduction stage, a novel feature extraction method and an optimal classification model with finely tuned hyperparameters. We carried out an exhaustive study comparing thousands of competing classification algorithms that were trained on our proprietary, large and expertly labeled dataset consisting of 12-lead ECGs from 40,258 patients with four arrhythmia classes: atrial fibrillation, general supraventricular tachycardia, sinus bradycardia and sinus rhythm including sinus irregularity rhythm. Our results show that the optimal approach consisted of Low Band Pass filter, Robust LOESS, Non Local Means smoothing, a proprietary feature extraction method based on percentiles of the empirical distribution of ratios of interval lengths and magnitudes of peaks and valleys, and Extreme Gradient Boosting Tree classifier, achieved an F1-Score of 0.988 on patients without additional cardiac conditions. The same noise reduction and feature extraction methods combined with Gradient Boosting Tree classifier achieved an F1-Score of 0.97 on patients with additional cardiac conditions. Our method achieved the highest classification accuracy (average 10-fold cross-validation F1-Score of 0.992) using an external validation data, MIT-BIH arrhythmia database. The proposed optimal multi-stage arrhythmia classification approach can dramatically benefit automatic ECG data analysis by providing cardiologist level accuracy and robust compatibility with various ECG data sources.

Field trial of a membraneless vacuum preloading system for soft soil improvement

This paper reports a field trial of membraneless vacuum preloading and fill surcharge to improve a compressible clay layer below sand fill at a reclaimed land site in Singapore. The thickness of the soft clay layer varied from 4 to 17 m. Due to the sand fill, a vacuum was applied to the clay layer using a proprietary membraneless method. Four weeks after the vacuum load was applied, a 2·5 m thick layer of sand fill was added as surcharge. Ground settlements, settlements and pore pressures at different depths in the soil were measured during the soil improvement. The measured field settlements and pore-pressure data were used to compute the degree of consolidation. The calculated values were found to differ considerably, the reasons for which are discussed. Experiences and lessons learned from the project are also highlighted.

Early-stage cervical cancer diagnosis based on an ultra-sensitive electrochemical DNA nanobiosensor for HPV-18 detection in real samples

BackgroundIn several years ago, infection with human papillomaviruses (HPVs), have been prevalent in the worlds especially HPV type 18, can lead to cervical cancer. Therefore, rapid, accurate, and early diagnosis of HPV for successful treatment is essential. The present study describes the development of a selective and sensitive electrochemical biosensor base on DNA, for early detection of HPV-18. For this purpose, a nanocomposite of reduced graphene oxide (rGO) and multiwalled carbon nanotubes (MWCNTs) were electrodeposited on a screen-printed carbon electrode (SPCE). Then, Au nanoparticles (AuNPs) were dropped on a modified SPCE. Subsequently, single strand DNA (ssDNA) probe was immobilized on the modified electrode. The link attached between AuNPs and probe ssDNA provided by l-cysteine via functionalizing AuNPs (Cys-AuNPs). The differential pulse voltammetry (DPV) assay was also used to electrochemical measurement. The measurement was based on the oxidation signals of anthraquninone-2-sulfonic acid monohydrate sodium salt (AQMS) before and after hybridization between the probe and target DNA.ResultsThe calibration curve showed a linear range between 0.01 fM to 0.01 nM with a limit of detection 0.05 fM. The results showed that the optimum concentration for DNA probe was 5 µM. The good performance of the proposed biosensor was achieved through hybridization of DNA probe-modified SPCE with extracted DNA from clinical samples.ConclusionsAccording to the investigated results, this biosensor can be introduced as a proprietary, accurate, sensitive, and rapid diagnostic method of HPV 18 in the polymerase chain reaction (PCR) of real samples.

The Use of Context-Free Probabilistic Grammar to Anonymise Statistical Data

In the following article, a proprietary method of anonymisation of identifiable statistical data using context-free probabilistic grammar is proposed. The advantage of this method is that it is simple and thanks to this, the identifier is easy to retrieve after masking the identifiable data, e.g. when it is necessary to modify or update the micro-data. This can be done using public-key cryptography, i.e. encrypting some probabilistic context-free grammar with this method. In the case of public statistics, there is often a need to use an anonymised source value, for example when economic operators’ reports are verified by statistical officers. With appropriate information generated by context-free grammar, the verifier can easily identify an economic operator or a natural person. The idea of the anonymising algorithm used in the proposed method is presented by means of an example. According to the authors, the combination of the proposed method with asymmetric encryption of the definition of context-free grammar using public key infrastructure, makes it probable that its resistance to attacks will be quite high. This is because statistical methods that are used in the analysis of natural languages are not susceptible to attacks.

SAMSUNG DISPLAY BETS ON FOLDABLE GLASS

SAMSUNG DISPLAY HAS MADE A substantial investment in the ultra-thin glass substrate firm Dowoo Insys, whose technology will be used by Samsung Electronics for its next generation of Galaxy Fold devices. In late December, Samsung Display acquired 600,000 shares of Dowoo Insys for 13.5 billion won, or $11.6 million, through a collaborative fund with Samsung Venture Investment Corp. The purchase makes Samsung the company's largest shareholder, with a 27.7 percent stake. Samsung Display has invested a total of 48.5 billion won, or $41.5 million, in Dowoo Insys since May 2018. According to Ross Young, CEO of the market research firm Display Supply Chain Consultants, Samsung's move to gain a controlling interest in Dowoo Insys makes sense as it looks to gain a competitive advantage in the nascent foldable market. Ultra-thin glass is expected to produce a more robust display than the colorless polyimides that Samsung used in its first Galaxy Fold product, providing a better feel and eliminating the visible crease in the flexible OLED display. “They think it's a strategic technology to make foldable more successful,” he said. Young notes that the ultra-thin glass Samsung will be using is actually produced by the German firm Schott, and that Dowoo Insys has a proprietary method for processing the glass. Opting for Ultra-Thin Glass Young believes a 1.5 mm radius will be implemented on the next Samsung foldable phone with Schott's ultra-thin glass. It was 3 mm in the first Galaxy Fold. Image: Samsung “Our understanding is that it could potentially be more than a single piece of glass in order to deal with the elongation,” Young said, adding that Dowoo Insys may also be helping to thin the glass and is expected to be laminating a protective film over it from another Korean supplier in case of any unforeseen cracking. Details from Dowoo Insys about its process are scarce, he said. As the foldable market expands, Young sees Schott having an early edge with its ultra-thin glass, which can be chemically strengthened and made thinner than some competing products. “They've talked about going as thin as 10 microns, but what's more likely is around 30 microns,” he said. “As the glass gets thinner, the fold radius gets smaller. We believe that they're going to be implementing a 1.5 millimeter (mm) radius on the next Samsung foldable phone with the ultra-thin glass.” In comparison, the radius of the first Galaxy Fold was 3 mm. The new Galaxy Fold, which is expected to use a clamshell design, will officially be unveiled in February. Although Samsung Display doesn't have an exclusive deal with Schott for its glass, it does have an exclusive deal with Dowoo Insys through its investment, which means that Samsung alone has access to the company's processing and laminating technology. Young says the Dowoo Insys deal is consistent with Samsung's recent emphasis on sourcing key technology from Korean suppliers in the wake of trade tensions with Japan. “They've become a lot more focused on self-sufficiency within Korea,” Young said. —Glen Dickson U.S. carriers may have launched limited 5G services months ahead of their Chinese counterparts, but at the close of 2019, Chinese carriers recorded almost 17 times the number of 5G phone sales, according to data from the market research firm M Science. Chinese carriers, the firm reports, have been selling more than 100,000 5G-phones every week since early November, while U.S. carriers haven't moved more than 15,000 5G phones per week since September. Why? Varied and competing 5G technologies on the U.S. end versus a standardized market in China (led by Huawei) are key. For the week of Dec. 7, the 5G adoption rate in the U.S. was 1.9 percent, having received a sizable bump after T Mobile launched its 5G network on Dec. 2, while in China the penetration rate was 3.42 percent, according to M Science. —Nicole Saunders Image: vchal/Shutterstock Image: vchal/Shutterstock

Studies of Body Weight/Heart Weight [C/S] Ratio in Treated and Untreated Experimental Pulmonary Barotrauma

Abstract The prerequisite of development of pulmonary barotrauma [PB] is retention of the breathing mix in the lungs during a sudden decrease in external pressure or its administration into the airways under increased pressure or in a volume exceeding the maximum lung capacity. In such cases, the pulmonary parenchyma ruptures and air enters both the pleural cavity and/or the lumen of ruptured blood vessels located in the alveolar septa. The result is permanent disruption of the pulmonary parenchyma. The aim of the study was to assess the influence of post-PB lesions on the heart muscle and the importance of hyperbaric treatment on the exacerbation of such lesions in the heart. The hearts of 35 rabbits were used in the study. In animals of the experimental group, PB was induced in the pressure chamber using the proprietary method described in previous publications. Part of the animals in this group were treated with air hyperbaria. The comparison group consisted of animals, which did not undergo PB during a simulated dive. All animals were weighed, observed for four weeks and then put to death following the experiment. In autopsy, among others, whole hearts were collected and weighed after fixation. Subsequently, the C/S ratio, i.e. the body to heart weight ratio, was calculated. The measurement results were subject to statistical analysis. A statistically significant increase in the C/S ratio was found, indicating an increase in the share of heart weight in the total body weight in the group of animals with PB not treated with air hyperbaria as compared to the control group.

1164. In vitro Antimicrobial Efficacy of Novel Antimicrobial Dacron Vascular Grafts in the Inhibition of Multidrug-Resistant Gram-Negative Biofilm

BackgroundVascular graft infections can be a devastating complication in vascular reconstructive surgery. Management of these infections is highly invasive and includes excision of the graft, debridement of infected material, and in situ reconstruction. There is a need for additional strategies for infection prevention in graft surgeries. The minocycline + rifampin + chlorhexidine (MRCH) triple combination had been previously demonstrated to be effective against biofilm formation in central venous catheters. In this study, we evaluated in vitro effectiveness and durability of MRCH coated Dacron vascular grafts in inhibiting multidrug-resistant Gram-negative biofilm formation.MethodsDacron vascular grafts were coated with MRCH based on a proprietary method. Antimicrobial efficacy at baseline and 3-week durability was assessed using a well-established in vitro biofilm colonization model. Multidrug-resistant Gram-negative pathogens tested include CRE Escherichia coli (EC), MDR Pseudomonas aeruginosa (PS) and CRE Klebsiella pneumoniae (KB). Antimicrobial durability was assessed for grafts that had been eluting in serum for 3 weeks prior to testing. Baseline and 3-week grafts were quantitatively culture to enumerate any biofilm viable biofilm colonization. Uncoated Dacron grafts were used as controls.ResultsAt baseline and 3 weeks MRCH vascular grafts completely inhibited biofilm formation resulting in an 8-log10 reduction in bacterial colonization compared with uncoated grafts.ConclusionMRCH coated Dacron vascular grafts demonstrated in vitro effectiveness for at least 3 weeks in preventing biofilm colonization by multidrug-resistant Gram-negative pathogens. Further in vivo testing is warranted. Disclosures All authors: No reported disclosures.