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Nevin Manimala Statistics

Tracking Nanoparticle Degradation across Fuel Cell Electrodes by Automated Analytical Electron Microscopy

ACS Nano. 2022 Jul 22. doi: 10.1021/acsnano.2c02307. Online ahead of print.

ABSTRACT

Nanoparticles are an important class of materials that exhibit special properties arising from their high surface area-to-volume ratio. Scanning transmission electron microscopy (STEM) has played an important role in nanoparticle characterization, owing to its high spatial resolution, which allows direct visualization of composition and morphology with atomic precision. This typically comes at the cost of sample size, potentially limiting the accuracy and relevance of STEM results, as well as the ability to meaningfully track changes in properties that vary spatially. In this work, automated STEM data acquisition and analysis techniques are employed that enable physical and compositional properties of nanoparticles to be obtained at high resolution over length scales on the order of microns. This is demonstrated by studying the localized effects of potential cycling on electrocatalyst degradation across proton exchange membrane fuel cell cathodes. In contrast to conventional, manual STEM measurements, which produce particle size distributions representing hundreds of particles, these high-throughput automated methods capture tens of thousands of particles and enable nanoparticle size, number density, and composition to be measured as a function of position within the cathode. Comparing the properties of pristine and degraded fuel cells provides statistically robust evidence for the inhomogeneous nature of catalyst degradation across electrodes. These results demonstrate how high-throughput automated STEM techniques can be utilized to investigate local phenomena occurring in nanoparticle systems employed in practical devices.

PMID:35867353 | DOI:10.1021/acsnano.2c02307

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Nevin Manimala Statistics

Self-Supervised Learning for Electroencephalography

IEEE Trans Neural Netw Learn Syst. 2022 Jul 22;PP. doi: 10.1109/TNNLS.2022.3190448. Online ahead of print.

ABSTRACT

Decades of research have shown machine learning superiority in discovering highly nonlinear patterns embedded in electroencephalography (EEG) records compared with conventional statistical techniques. However, even the most advanced machine learning techniques require relatively large, labeled EEG repositories. EEG data collection and labeling are costly. Moreover, combining available datasets to achieve a large data volume is usually infeasible due to inconsistent experimental paradigms across trials. Self-supervised learning (SSL) solves these challenges because it enables learning from EEG records across trials with variable experimental paradigms, even when the trials explore different phenomena. It aggregates multiple EEG repositories to increase accuracy, reduce bias, and mitigate overfitting in machine learning training. In addition, SSL could be employed in situations where there is limited labeled training data, and manual labeling is costly. This article: 1) provides a brief introduction to SSL; 2) describes some SSL techniques employed in recent studies, including EEG; 3) proposes current and potential SSL techniques for future investigations in EEG studies; 4) discusses the cons and pros of different SSL techniques; and 5) proposes holistic implementation tips and potential future directions for EEG SSL practices.

PMID:35867362 | DOI:10.1109/TNNLS.2022.3190448

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Nevin Manimala Statistics

The Phylogenetic Position of the Enigmatic, Polypodium hydriforme (Cnidaria, Polypodiozoa): Insights from Mitochondrial Genomes

Genome Biol Evol. 2022 Jul 22:evac112. doi: 10.1093/gbe/evac112. Online ahead of print.

ABSTRACT

Polypodium hydriforme is an enigmatic parasite that belongs to the phylum Cnidaria. Its taxonomic position has been debated: while it was previously suggested to be part of Medusozoa, recent phylogenomic analyses based on nuclear genes support the view that P. hydriforme and Myxozoa form a clade called Endocnidozoa. Medusozoans have linear mitochondrial (mt) chromosomes while myxozoans, as most metazoan species, have circular chromosomes. In this work, we determined the structure of the mt genome of P. hydriforme, using Illumina and Oxford Nanopore Technologies reads, and showed that it is circular. This suggests that P. hydriforme is not nested within Medusozoa, as this would entail linearization followed by re-circulation. Instead, our results support the view that P. hydriforme is a sister clade to Myxozoa, and mt linearization in the lineage leading to medusozoans occurred after the divergence of Myxozoa + P. hydriforme. Detailed analyses of the assembled P. hydriforme mt genome show that: (1) It is encoded on a single circular chromosome with an estimated size of ∼93,000 base pairs, making it one of the largest metazoan mt genomes; (2) Around 78% of the genome encompasses a non-coding region composed of several repeat types; (3) Similar to Myxozoa, no mt tRNAs were identified; (4) The codon TGA is a stop codon and does not encode for tryptophan as in other cnidarians; (5) Similar to other myxozoan mt genomes, it is extremely fast-evolving.

PMID:35867352 | DOI:10.1093/gbe/evac112

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Nevin Manimala Statistics

Obesity and labour market outcomes in Italy: a dynamic panel data evidence with correlated random effects

Eur J Health Econ. 2022 Jul 22. doi: 10.1007/s10198-022-01493-3. Online ahead of print.

ABSTRACT

This paper investigates the effects of obesity, socio-economic variables, and individual-specific factors on work productivity across Italian regions. A dynamic panel data with correlated random effects is used to jointly deal with incidental parameters, endogeneity issues, and functional forms of misspecification. Methodologically, a hierarchical semiparametric Bayesian approach is involved in shrinking high dimensional model classes, and then obtaining a subset of potential predictors affecting outcomes. Monte Carlo designs are addressed to construct exact posterior distributions and then perform accurate forecasts. Cross-sectional Heterogeneity is modelled nonparametrically allowing for correlation between heterogeneous parameters and initial conditions as well as individual-specific regressors. Prevention policies and strategies to handle health and labour market prospects are also discussed.

PMID:35867310 | DOI:10.1007/s10198-022-01493-3

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Nevin Manimala Statistics

Research on carbon emission measurement and low-carbon path of regional industry

Environ Sci Pollut Res Int. 2022 Jul 22. doi: 10.1007/s11356-022-22006-y. Online ahead of print.

ABSTRACT

As industry is the world’s leading carbon emitter, promoting industrial carbon reduction is of key significance to carbon peak and carbon neutrality. Using a data-driven method, based on the collection and processing of relevant data from statistical yearbooks and others, we analyze the efficiency and amount of carbon emission of each industrial sector after processing multi-dimensional data by the improved IPCC EF method of calculating carbon emissions. In addition, we adopt the LMDI decomposition method for data modeling to measure the contribution of energy efficiency, industrial structure, GDP per capita, and population size to carbon emission changes, to identify targets for industrial carbon reduction, and to propose a targeted optimization path for carbon emission. We show how the method is implemented by taking the statistics of Anhui Province from 2010 to 2019 as an example and advises on an optimization path for carbon emission in Anhui Province. This study is of both theoretical and practical significance as it provides theoretical and methodological support for the low-carbon development of the regional industry, and provides a reference for other countries and regions to explore the path of low-carbon and environment-friendly green transformation and upgrading.

PMID:35867299 | DOI:10.1007/s11356-022-22006-y

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Nevin Manimala Statistics

Comparison of clinical outcomes of non-surgical adjunctive use of the 980-nm diode laser to conventional periodontal flap procedure-a randomised controlled split-mouth clinical trial

Lasers Med Sci. 2022 Jul 22. doi: 10.1007/s10103-022-03605-0. Online ahead of print.

ABSTRACT

Lasers have been found to be effective as an adjunctive in periodontal therapy. The objective of the study was to compare the outcomes of non-surgical adjunctive use of 980-nm diode laser to that of conventional flap surgery in terms of clinical outcome measures and radiographic osseous defect depths. This study was designed as a double-blinded split-mouth randomised controlled clinical trial. A total of fifteen patients (30 quadrants) with generalised periodontitis stage III grade B were randomly assigned test group (diode laser) and control group (conventional flap surgery). Both test and control groups had 15 quadrants each. At 3 months, the probing pocket depth (PPD) was 3.46 ± 0.19 mm (test) and 4.20 ± 0.20 mm (control), with a statistically significant difference between the groups (p = 0.01). Similarly, at 6 months re-evaluation, PPD was 1.46 ± 0.12 mm (test) and 2.33 ± 0.13 mm (control) with a highly significant statistical difference (p = 0.001). Plaque index showed a difference between both test and control groups at baseline, 3 months and 6 months (p = 0.001) while gingival index, modified sulcular bleeding index and radiographic osseous defect depth showed a difference at 3 months and 6 months (p = 0.001). Within the study’s limitations, 980-nm diode laser can result in significant improvements in the clinical and radiographic parameters and is very well tolerated by the subjects.

PMID:35867285 | DOI:10.1007/s10103-022-03605-0

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Nevin Manimala Statistics

High-Throughput DNA FISH (hiFISH)

Methods Mol Biol. 2022;2532:245-274. doi: 10.1007/978-1-0716-2497-5_12.

ABSTRACT

High-throughput DNA fluorescence in situ hybridization (hiFISH) combines multicolor combinatorial DNA FISH staining with automated image acquisition and analysis to visualize and localize tens to hundreds of genomic loci in up to millions of cells. hiFISH can be used to measure physical distances between pairs of genomic loci, radial distances from genomic loci to the nuclear edge or center, and distances between genomic loci and nuclear structures defined by protein or RNA markers. The resulting large datasets of 3D spatial distances can be used to study cellular heterogeneity in genome architecture and the molecular mechanisms underlying this phenomenon in a variety of cellular systems. In this chapter we provide detailed protocols for hiFISH to measure distances between genomic loci, including all steps involved in DNA FISH probe design and preparation, cell culture, DNA FISH staining in 384-well imaging plates, automated image acquisition and analysis, and, finally, statistical analysis.

PMID:35867253 | DOI:10.1007/978-1-0716-2497-5_12

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Nevin Manimala Statistics

The role of immune checkpoint receptors in the malignant phenotype of cutaneous T cell lymphoma

Immunol Res. 2022 Jul 22. doi: 10.1007/s12026-022-09308-6. Online ahead of print.

ABSTRACT

Immune checkpoint receptors (ICR) modulate the immune response and are critical hubs for immunotherapy. However, data on their role in T lymphoid malignancies, such as cutaneous T cell lymphoma (CTCL), is sparse. We aimed to explore the role of ICR in the malignant features of transformed T lymphocytes and evaluate the effect of ICR-targeting monoclonal antibodies, often used as immunotherapy for solid tumors. We used the CTCL cell line HH and the Sézary cell line Hut78 to examine ICR expression and the effects of ICR inhibition on cell viability and proliferation. Despite their shared T cell progeny, the different CTCL cell lines exhibit markedly different ICR expression profiles. Programmed cell death-ligand 1 (PD-L1) was expressed by both cell lines, while programmed death-1 (PD-1) was expressed only by the HH cell line. Common to all malignant T cells was an autonomous hyper-proliferative state that did not require T cell receptor stimulation. A monoclonal antibody blocking PD-1 had a small but statistically significant augmenting effect on T cell proliferation. Of note, when the cells were exposed to ionizing radiation, healthy lymphocytes and those derived from the HH cell line were salvaged by anti-PD-L1. We show a regulatory role of ICR, mainly PD-1 and its ligand PD-L1, on cutaneous T cell malignancy.

PMID:35867216 | DOI:10.1007/s12026-022-09308-6

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Nevin Manimala Statistics

Rotating Factors to Simplify Their Structural Paths

Psychometrika. 2022 Jul 22. doi: 10.1007/s11336-022-09877-3. Online ahead of print.

ABSTRACT

Applications of structural equation modeling (SEM) may encounter issues like inadmissible parameter estimates, nonconvergence, or unsatisfactory model fit. We propose a new factor rotation method that reparameterizes the factor correlation matrix in exploratory factor analysis (EFA) such that factors can be either exogenous or endogenous. The proposed method is an oblique rotation method for EFA, but it allows directional structural paths among factors. We thus referred it to as FSP (factor structural paths) rotation. In particular, we can use FSP rotation to “translate” an SEM model to incorporate theoretical expectations on both factor loadings and structural parameters. We illustrate FSP rotation with an empirical example and explore its statistical properties with simulated data. The results include that (1) EFA with FSP rotation tends to fit data better and encounters fewer Heywood cases than SEM does when there are cross-loadings and many small nonzero loadings, (2) FSP rotated parameter estimates are satisfactory for small models, and (3) FSP rotated parameter estimates are more satisfactory for large models when the structural parameter matrices are sparse.

PMID:35867178 | DOI:10.1007/s11336-022-09877-3

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Nevin Manimala Statistics

Outcomes of arthroscopic-assisted lateral tibial plateau fixation: a systematic review

Eur J Orthop Surg Traumatol. 2022 Jul 22. doi: 10.1007/s00590-022-03339-3. Online ahead of print.

ABSTRACT

PURPOSE: The purpose of this study is to evaluate and summarize the current literature on outcomes of arthroscopic-assisted tibial plateau fixation (AATPF) when applied for only lateral tibial plateau fractures.

METHODS: A comprehensive search of nine databases was conducted: ClinicalTrials.gov, Cochrane Library via Wiley, Embase and MEDLINE via Ovid, Global Index Medicus, PubMed, Scopus, SPORTDiscus via EBSCO, and Web of Science Core Collection. The study was performed in concordance with PRISMA guidelines. Studies eligible for inclusions included Schatzker I-III lateral tibial plateau fractures with a minimum of 6-month follow-up. Data extraction was performed by two authors independently using a predesigned form.

RESULTS: A total of 17 studies, 7 prospective and 10 retrospective, including 565 patients (age 15-82 years old) treated with AATPF were included in this review with follow-up ranging from 6 to 138 months. All 10 studies that used categorical functional outcomes demonstrated excellent/very good or good outcomes in > 90% of patients. When compared to patients managed with the traditional open reduction internal fixation (ORIF), patients treated with AATPF had statistically significantly better range of motion mean difference [5.21° (95% CI – 2.50 to 12.92, p < 0.0001)], lower blood loss [66.19 mL (95% confidence interval (CI) 32.54-99.84 mL, p < 0.0001)], shorter hospital stay [- 1.41 days (95% CI – 3.39 to 0.58 days, p < 0.0001)], better Hospital Special Surgery score [11.31 (95% CI 6.49-16.12, p < 0.0001)], and higher Rasmussen radiographic score [1.26 (95% CI – 0.72 to 3.23, p < 0.0001)].

CONCLUSION: AATPF is a promising treatment of lateral tibial plateau fractures with some advantages over the traditional ORIF.

LEVEL OF EVIDENCE: Therapeutic Level III.

PMID:35867167 | DOI:10.1007/s00590-022-03339-3