Methods textbooks in sociology and other social sciences routinely recommend the use of the logit or probit model when an outcome variable is binary, an ordered logit or ordered probit when it is ...ordinal, and a multinomial logit when it has more than two categories. But these methodological guidelines take little or no account of a body of work that, over the past 30 years, has pointed to problematic aspects of these nonlinear probability models and, particularly, to difficulties in interpreting their parameters. In this review, we draw on that literature to explain the problems, show how they manifest themselves in research, discuss the strengths and weaknesses of alternatives that have been suggested, and point to lines of further analysis.
Extracellular vesicles (EV) play a role in intercellular communication by delivering biologically active molecules to specific targets. EV composition and content vary by cell type and culture ...condition, complicating their understanding. Using MISEV2018 as a guide, we have therefore created a platform for the consistent isolation and characterization of a bank of human EV from many different cell types. Mining this gold-standard dataset will help unravel the characteristics of different EV and their potential in therapeutics and research.
Mother-cells were differentiated from human induced pluripotent stem cells under highly controlled conditions, passing quality control tests confirming identity and purity. Mock virgin media controls (MV; media cultured in identical conditions but without cells) were prepared for every cell type of interest. Conditioned media, media controls, and mother-cells were collected and pre-processed using a standardized method. EV/MV were isolated by ultracentrifugation, affinity capture, size exclusion chromatography, and/or tangential flow filtration. EV/MV were then characterized using a systematic approach including nanoparticle tracking analysis, microfluidic resistive pulse sensing, total protein analysis, ELISA, super resolution microscopy, flow cytometry, cryo-TEM, automated Western blot, and miR sequencing. Mother-cell miR were processed and sequenced in parallel.
Using our EV platform, we have isolated 88 EV samples from 38 different mother-cell types in culture, including apparently healthy normal and disease model lines. We also have 46 MV controls (23 types), and 61 mother-cell samples (31 types). All samples were characterized using our systematic approach, generating a large library of comparable data. The data were mined to compare and distinguish EV from one another, identifying cell and EV-type specific characteristics. Already we have seen signatures in both EV tetraspanin expression and miRNA profiles that cluster first by biological replicate, then by cell type, and finally by related cell type, such as by germ layer. The results confirm the biological relevance of the data generated, and validate the value of our systematic and standardized approach.
Our standardized EV isolation and characterization platform, resulting EV biobank, and data library will help better understand EV and their potential application to therapeutics, diagnostics, drug delivery, and more.
Tämän artikkelin ensimmäinen osa kertoo International Organization for Standardization (ISO) ja Suomen standardisoimisliitto SFS ry -standardisointijärjestöistä ja niiden toiminnasta. Artikkelin ...seuraavassa Signumin numerossa julkaistava toinen osa kuvaa käytännön kokemukseen perustuen standardisointiprosessien ongelmia yleensä.
Models of human flows and their influence on spacial arrangement of buildings and facilities are considered. A review of simulation programs for people evacuation procedure in the event of fire was ...performed. Advices on using of human flow models in standardization of escape routes are provided.
Results: After assessment of 4 factors for kit standardization in this investigation the best results was achived with: the number of coated bacteria 5×?10?^6 bacteria per well; serum dilution 1: 50; ...conjugate dilution 1: 4000 and 15 min colour developing time.
Reply Fox, Austin R; Gordon, Lynn K; Heckenlively, John R ...
American journal of ophthalmology,
10/2016, Letnik:
170
Journal Article
Recenzirano
...clinical validation requires a gold standard (a reliable clinical phenotype), which, as of yet, does not exist for autoimmune retinopathy. ...it will be difficult to validate ARA testing without a ...consensus on clinical diagnosis and a standardized approach to ARA testing.
With a great success of the generative model via deep neural networks, monocular depth estimation has been actively studied by exploiting various encoder-decoder architectures. However, the decoding ...process in most previous methods, which repeats simple up-sampling operations, probably fails to fully utilize underlying properties of well-encoded features for monocular depth estimation. To resolve this problem, we propose a simple but effective scheme by incorporating the Laplacian pyramid into the decoder architecture. Specifically, encoded features are fed into different streams for decoding depth residuals, which are defined by decomposition of the Laplacian pyramid, and corresponding outputs are progressively combined to reconstruct the final depth map from coarse to fine scales. This is fairly desirable to precisely estimate the depth boundary as well as the global layout. We also propose to apply weight standardization to pre-activation convolution blocks of the decoder architecture, which gives a great help to improve the flow of gradients and thus makes optimization easier. Experimental results on benchmark datasets constructed under various indoor and outdoor environments demonstrate that the proposed method is effective for monocular depth estimation compared to state-of-the-art models. The code and model are publicly available at: | https://github.com/tjqansthd/LapDepth-release |.
Ultra-high bandwidth, negligible latency and seamless communication are envisioned as milestones that will revolutionize the way by which societies create, distribute and consume information. The ...remarkable expansion of wireless data traffic has advocated the investigation of suitable regimes in the radio spectrum to satisfy users' escalating requirements and allow the exploitation of massive capacity and massive connectivity. To this end, the Terahertz (THz) frequency band (0.1-10 THz) has received noticeable attention in the research community as an ideal choice for scenarios involving high-speed transmission. As such, in this work, we present an up-to-date review paper to analyze key concepts associated with the THz system architecture. THz generation methods are first addressed by highlighting the recent progress in the devices technology. Moreover, the recently proposed channel models available for propagation at THz band frequencies are introduced. A comprehensive comparison is then presented between the THz wireless communication and its other contenders. In addition, several applications of THz communication are discussed taking into account various scales. Further, we highlight the milestones achieved regarding THz standardization activities. Finally, a future outlook is provided by presenting and envisaging several potential use cases and attempts to guide the deployment of the THz frequency band.
Microplastics are emerging pollutants in aquatic and terrestrial environments. In the last years, several case studies and reviews have been published about microplastics in freshwater and marine ...environments. However, no standardized methods are available for sampling and sample preparation. Based on literature research, this review presents different techniques and methods for sampling as well as the preparation of microplastic samples from water, sediment and biota of freshwater and marine environments. Several methods are used for sampling and sample preparation (e.g., organic digestion and density separation) which influence the interpretation of results and hamper their comparability. The results clearly show that the basis for the interpretation of the results of microplastic monitoring is the consistency of a sampling strategy. Until standardization and harmonization both for sampling and sample preparation is implemented, further research about processing of samples and analysis techniques is necessary.
•Comparison of different sampling methods for water, sediment and biota.•Sample preparation with organic digestion and density separation.•Standardization and harmonization of sampling and sample preparation methods is needed.
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