Comparison of diagnostic accuracy for eight SARS-CoV-2 serological assays

IntroductionSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests have been suggested as an additional diagnostic tool in highly suspected cases with a negative molecular test and determination of seroprevalence in population. We compared the diagnostic performance of eight commercial serological assays for IgA, IgM, and IgG antibodies to the SARS-CoV-2 virus.Materials and methodsThe comparison study was performed on a total of 76 serum samples: 30 SARS-CoV-2 polymerase chain reaction (PCR)-negative and 46 SARS-CoV-2 PCR-positive patients with asymptomatic to severe disease and symptoms duration from 3-30 days. The study included: three rapid lateral flow immunochromatographic assays (LFIC), two enzyme-linked immunosorbent assays (ELISA), and three chemiluminescence immunoassays (CLIA).ResultsAgreement between IgM assays were minimal to moderate (kappa 0.26 to 0.63) and for IgG moderate to excellent (kappa 0.72 to 0.92). Sensitivities improved with > 10 days of symptoms and were: 30% to 89% for IgM; 89% to 100% for IgG; 96% for IgA; 100% for IgA/IgM combination; 96% for total antibodies. Overall specificities were: 90% to 100% for IgM; 85% to 100% for IgG; 90% for IgA; 70% for IgA/IgM combination; 100% for total antibodies. Diagnostic accuracy for IgG ELISA and CIA assays were excellent (AUC ≥ 0.90), without significant difference. IgA showed significantly better diagnostic accuracy than IgM (P < 0.001).ConclusionThere is high variability between IgM assays independently of the assay format, while IgG assays showed moderate to perfect agreement. The appropriate time for testing is crucial for the proper immunity investigation.     

Measurement of fluid flow generated by artificial cilia

We observed and measured the fluid flow that was generated by an artificial cilium. The cilium was composed of superparamagnetic microspheres, in which magnetic dipole moments were induced by an external magnetic field. The interaction between the dipole moments resulted in formation of long chains-cilia, and the same external magnetic field was also used to drive the cilia in a periodic manner. Asymmetric periodic motion of the cilium resulted in generation of fluid flow and net pumping of the surrounding fluid. The flow and pumping performance were closely monitored by introducing small fluorescent tracer particles into the system. By detecting their motion, the fluid flow around an individual cilium was mapped and the flow velocities measured. We confirm that symmetric periodic beating of one cilium results in vortical motion only, whereas asymmetry is required for additional translational motion. We determine the effect of asymmetry on the pumping performance of a cilium, verify the theoretically predicted optimal pumping conditions, and determine the fluid behaviour around a linear array of three neighbouring cilia. In this case, the contributions of neighbouring cilia enhance the maximal flow velocity compared with a single cilium and contribute to a more uniform translational flow above the surface.     

Children’s Participation in Slovene Preschools: The Teachers’ Viewpoints and Practice

This article presents part of the research performed in a project from 2008 to 2013, regarding the introduction of the Reggio Emilia approach to Slovene preschool educators. The study’s aim was to recognize the possible influence of the training—from 2009 to 2011—in this project on educators’ viewpoints and the promotion of children’s participation in practice. We believe that a potential reform of the Slovene national curriculum should establish the participation of children as one of its key principles. It seems that the two-year intensive training of educators, followed by projects in preschool practice, has been a successful step in this direction.     

New Perspectives on the Study of Particulate Matter Deposition within Historic Interiors

ABSTRACT

This paper proposes a new way of interpreting particulate matter deposition indoors. The rate of deposition of dust in surfaces is presented as the result of the combination of two main factors: the concentration of suspended particles close to surfaces, and their capacity to deposit, expressed as the deposition velocity. We suggest that either of these two factors can be altered in order to mitigate deposition. The implications of this perspective are explored using in-situ measurements in a historic property (Apsley House, London) and a computational fluid dynamics model of aerosol deposition. The cases studied involve the effect of outdoor wind on the ingress of particles, the consequences of leaving the main door open, and the effects of the ventilation system on deposition. The results demonstrate that simulations can be used reliably to explore hypothetical scenarios or situations that would be experimentally challenging. The inputs and outputs of the computational model are discussed in view of its usability in preventive conservation.     

“You Don't Understand,This is a New War!” Analysis of Hate Speech in News Web Sites' Comments

Because news websites' comments have become an important space of spreading hate speech, this article tries to contribute to uncovering the characteristics of Internet hate speech by combining discourse analyses of comments on Slovenian news websites with online in-depth interviews with producers of hate speech comments, researching their values, beliefs, and motives for production. Producers of hate speech use different strategies, mostly rearticulating the meaning of news items. The producers either are organized or act on their own initiative. The main motive of soldiers and believers is the mission; they share characteristics of an authoritarian personality. The key motives of the players are thrill and fun. The watchdogs are motivated by drawing attention to social injustice. The last two groups share the characteristics of a libertarian personality.     

Center for Czechoslovak Exile Studies in Olomouc: Survey of the Past Twenty Years of Activity (1993–2013)

The article describes activities of the Center for Czechoslovak Exile Studies in Olomouc particularly for the period 2004–2013. During this period the center acquired many significant archival collections.     

Remembering Nina Lenček, 18 January 1924–25 November 2014

Columbia University Libraries’ longtime Slavic & East European Studies Librarian Nina Len?ek passed away on November 25, 2014, at the age of 90. On January 22, 2015, a large group of her friends, family, and colleagues gathered at Butler Library to remember, honor, and celebrate her remarkable life and legacy.