Molecular identification of viral pathogens in SPF (Specific pathogen free) shrimp

After the outbreak of various viral diseases, specifically white spot syndrome (WSS) in farmed Litopenaeus vannamei in the past few years, this non-native shrimp species in Iran requires a generator-builder with specific a pathogen-free approach. This Research was done by the Iran Shrimp Research Center (ISRC) to access accurate information regarding specific pathogen-free shrimp production and avoid using shrimp broodstock production through foreign investors. This research was part of the molecular viral study. For this trial, selected shrimps in farms were sampled and screened for main viruses (OIE list). Shrimps without infection were brought to the quarantine system for one month and at the end of the quarantine they were screened again. In addition, in winter spending, before and after spawning, it’s offspring in F1 and F2 were also screened for viral pathogens by IQ2000 kit at the Iran Shrimp Research Center lab and Iranian veterinary organization lab. All shrimp products such as fresh and consumed food were tested for OIE list at all stages during project performance and the result of tests were negative. Sequenced and molecular tests with specific primers were used to determine the presence of infected samples carrying the virus in any of the products, such as shrimp and consumed food, the infected samples. The result of all the tests during last three years, shows that all the shrimp and their food products were pathogen-free and safe to use

A Typology of Digital Sharing Business Models: A Design Science Research Approach

The digitally enabled sharing economy, also called the “digital sharing economy” (DSE), has changed patterns of consumption by introducing new choices and channels for provision and receipt of services. The DSE encompasses sharing systems whose business models may vary distinctly from platform to platform. Although business models in the context of the sharing economy have been studied so far, we have observed that the current literature does not provide an approach that covers all the possible business models (in the broadest sense of the term) that (potentially) exist within the scope of the DSE. The present paper, therefore, aims to propose a typology of business models in the DSE that covers a wide space of models – even those which may not involve “business” in the commercial sense. This is achieved through an iterative inductive process based on a design science research approach. The typology can assist in positioning the current and future sharing systems in the DSE by systematically classifying their business models. It is intended to serve as a guiding tool for the sustainability assessment of platforms from both resource and socio-economic perspectives. The present study can also enable researchers and practitioners to capture and systematically analyse digital sharing business models based on a structured, actionable approach

Potentiometric pH Nanosensor for Intracellular Measurements: Real-Time and Continuous Assessment of Local Gradients

We present a pH nanosensor conceived for single intracellular measurements. The sensing architecture consisted of a two-electrode system evaluated in the potentiometric mode. We used solid-contact carbon nanopipette electrodes tailored to produce both the indicator (pH nanosensor) and reference electrodes. The indicator electrode was a membrane-based ion-selective electrode containing a receptor for hydrogen ions that provided a favorable selectivity for intracellular measurements. The analytical features of the pH nanosensor revealed a Nernstian response (slope of −59.5 mV/pH unit) with appropriate repeatability and reproducibility (variation coefficients of <2% for the calibration parameters), a fast response time (<5 s), adequate medium-term drift (0.7 mV h–1), and a linear range of response including physiological and abnormal cell pH levels (6.0–8.5). In addition, the position and configuration of the reference electrode were investigated in cell-based experiments to provide unbiased pH measurements, in which both the indicator and reference electrodes were located inside the same cell, each of them inside two neighboring cells, or the indicator electrode inside the cell and the reference electrode outside of (but nearby) the studied cell. Finally, the pH nanosensor was applied to two cases: (i) the tracing of the pH gradient from extra-to intracellular media over insertion into a single PC12 cell and (ii) the monitoring of variations in intracellular pH in response to exogenous administration of pharmaceuticals. It is anticipated that the developed pH nanosensor, which is a label-free analytical tool, has high potential to aid in the investigation of pathological states that manifest in cell pH misregulation, with no restriction in the type of targeted cells.Farmaci