A Situation-aware Scenario-based Testing Strategy

Purpose Recent papers on target capital structure show that debt ratio seems to vary widely in space and time, implying that the functional specifications of target debt ratios are of little empirical use. Further, target behavior cannot be adjudged correctly using debt ratios, as they could revert due to mechanical reasons. The purpose of this paper is to develop an alternative testing strategy to test the target capital structure. Design/methodology/approach The authors make use of a major “shock” to the debt ratios as an event and think of a subsequent reversion as a movement toward a mean or target debt ratio. By doing this, the authors no longer need to identify target debt ratios as a function of firm-specific variables or any other rigid functional form. Findings Similar to the broad empirical evidence in developed economies, there is no perceptible and systematic mean reversion by Indian firms. However, unlike developed countries, proportionate usage of debt to finance firms’ marginal financing deficits is extensive; equity is used rather sparingly. Research limitations/implications The trade-off theory could be convincingly refuted at least for the emerging market of India. The paper here stimulated further research on finding reasons for specific financing behavior of emerging market firms. Practical implications The results show that the firms’ financing choices are not only depending on their own firm’s specific variables but also on the financial markets in which they operate. Originality/value This study attempts to assess mean reversion in debt ratios in a unique but reassuring manner. The results are confirmed by extensive calibration of the testing strategy using simulated data sets.

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Pooled testing with replication as a mass testing strategy for the COVID-19 pandemics

Scientific Reports ◽

10.1038/s41598-021-83104-4 ◽

2021 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Julius Žilinskas ◽

Algirdas Lančinskas ◽

Mario R. Guarracino

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Group Testing ◽

Testing Strategy ◽

Testing Technique ◽

Testing Procedures ◽

Pooled Testing ◽

Replication Scheme ◽

Speed Up ◽

Multiple Patients

AbstractDuring the COVID-19 pandemic it is essential to test as many people as possible, in order to detect early outbreaks of the infection. Present testing solutions are based on the extraction of RNA from patients using oropharyngeal and nasopharyngeal swabs, and then testing with real-time PCR for the presence of specific RNA filaments identifying the virus. This approach is limited by the availability of reactants, trained technicians and laboratories. One of the ways to speed up the testing procedures is a group testing, where the swabs of multiple patients are grouped together and tested. In this paper we propose to use the group testing technique in conjunction with an advanced replication scheme in which each patient is allocated in two or more groups to reduce the total numbers of tests and to allow testing of even larger numbers of people. Under mild assumptions, a 13 × average reduction of tests can be achieved compared to individual testing without delay in time.

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Genotoxic and teratogenic effect of freshwater sediment samples from the Rhine and Elbe River (Germany) in zebrafish embryo using a multi-endpoint testing strategy

Environmental Science and Pollution Research ◽

10.1007/s11356-014-3894-4 ◽

2014 ◽

Vol 22 (21) ◽

pp. 16341-16357 ◽

Cited By ~ 9

Author(s):

M. Garcia-Käufer ◽

S. Gartiser ◽

C. Hafner ◽

S. Schiwy ◽

S. Keiter ◽

...

Keyword(s):

Zebrafish Embryo ◽

Teratogenic Effect ◽

Freshwater Sediment ◽

Testing Strategy ◽

Elbe River ◽

Sediment Samples

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INSIGHT: A population-scale COVID-19 testing strategy combining point-of-care diagnosis with centralized high-throughput sequencing

Science Advances ◽

10.1126/sciadv.abe5054 ◽

2021 ◽

Vol 7 (7) ◽

pp. eabe5054

Author(s):

Qianxin Wu ◽

Chenqu Suo ◽

Tom Brown ◽

Tengyao Wang ◽

Sarah A. Teichmann ◽

...

Keyword(s):

High Throughput ◽

High Throughput Sequencing ◽

Limit Of Detection ◽

Point Of Care ◽

Population Level ◽

Reaction Products ◽

Testing Strategy ◽

Asymptomatic Patients ◽

Testing Stage ◽

Population Scale

We present INSIGHT [isothermal NASBA (nucleic acid sequence–based amplification) sequencing–based high-throughput test], a two-stage coronavirus disease 2019 testing strategy, using a barcoded isothermal NASBA reaction. It combines point-of-care diagnosis with next-generation sequencing, aiming to achieve population-scale testing. Stage 1 allows a quick decentralized readout for early isolation of presymptomatic or asymptomatic patients. It gives results within 1 to 2 hours, using either fluorescence detection or a lateral flow readout, while simultaneously incorporating sample-specific barcodes. The same reaction products from potentially hundreds of thousands of samples can then be pooled and used in a highly multiplexed sequencing–based assay in stage 2. This second stage confirms the near-patient testing results and facilitates centralized data collection. The 95% limit of detection is <50 copies of viral RNA per reaction. INSIGHT is suitable for further development into a rapid home-based, point-of-care assay and is potentially scalable to the population level.

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Effect of Poly(L-lysine) and Heparin Coatings on the Surface of Polyester-Based Particles on Prednisolone Release and Biocompatibility

Pharmaceutics ◽

10.3390/pharmaceutics13060801 ◽

2021 ◽

Vol 13 (6) ◽

pp. 801

Author(s):

Abdelrahman Mohamed ◽

Viktor Korzhikov-Vlakh ◽

Nan Zhang ◽

André Said ◽

Iuliia Pilipenko ◽

...

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Molecular Diffusion ◽

Corneal Opacity ◽

Testing Strategy ◽

Release Process ◽

Irritation Test ◽

Model Drug ◽

Novel Drug ◽

Permeability Assay

A plethora of micro- and nanoparticle types are currently investigated for advanced ocular treatment due to improved drug retention times, higher bioavailability and better biocompatibility. Yet, comparative studies of both physicochemical and toxicological performance of these novel drug delivery systems are still rare. Herein, poly(L-lactic acid)- and poly(ε-caprolactone)-based micro- and nanoparticles were loaded with prednisolone as a model drug. The physicochemical properties of the particles were varied with respect to their hydrophilicity and size as well as their charge and the effect on prednisolone release was evaluated. The particle biocompatibility was assessed by a two-tier testing strategy, combining the EpiOcularTM eye irritation test and bovine corneal opacity and permeability assay. The biodegradable polyelectrolyte corona on the particles’ surface determined the surface charge and the release rate, enabling prednisolone release for at least 30 days. Thereby, the prednisolone release process was mainly governed by molecular diffusion. Finally, the developed particle formulations were found to be nontoxic in the tested range of concentrations.

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