Factors Affecting Capture Rates of Insect Taxa by Retail Electrocutors and Eliminators in Northern Lower Michigan

We compare the abundance and types of insects captured at several locations, with and without a chemical attractant and in varying weather conditions using two different devices advertised to kill biting insects. Using both an insect electrocutor that uses ultraviolet light as an attractant, with and without octenol as an added attractant, and an insect eliminator that uses carbon dioxide, heat and octenol as attractants, more non-biting than biting insects were captured. Numerous harmless and beneficial insects were killed with electrocutors. Although eliminators were more target-specific, they captured fewer insects overall compared to electrocutors. The numbers and types of insects captured also varied by location and temperature conditions. More insects were killed by electrocutors located next to a lake compared to those located in an inland forested area and more were killed at lower compared to higher heights above the ground. More insects were also killed by electrocutors on warmer than on cooler nights. More non-biting insects were killed with electrocutors baited with octenol than without octenol

Factors Affecting Capture Rates of Insect Taxa by Retail Electrocutors and Eliminators in Northern Lower Michigan

We compare the abundance and types of insects captured at several locations, with and without a chemical attractant and in varying weather conditions using two different devices advertised to kill biting insects. Using both an insect electrocutor that uses ultraviolet light as an attractant, with and without octenol as an added attractant, and an insect eliminator that uses carbon dioxide, heat and octenol as attractants, more non-biting than biting insects were captured. Numerous harmless and beneficial insects were killed with electrocutors. Although eliminators were more target-specific, they captured fewer insects overall compared to electrocutors. The numbers and types of insects captured also varied by location and temperature conditions. More insects were killed by electrocutors located next to a lake compared to those located in an inland forested area and more were killed at lower compared to higher heights above the ground. More insects were also killed by electrocutors on warmer than on cooler nights. More non-biting insects were killed with electrocutors baited with octenol than without octenol

A Microphysiological System for Studying Nonalcoholic Steatohepatitis

Nonalcoholic steatohepatitis (NASH) is the most severe form of nonalcoholic fatty liver disease (NAFLD), which to date has no approved drug treatments. There is an urgent need for better understanding of the genetic and molecular pathways that underlie NAFLD/NASH, and currently available preclinical models, be they in vivo or in vitro, do not fully represent key aspects of the human disease state. We have developed a human in vitro co‐culture NASH model using primary human hepatocytes, Kupffer cells and hepatic stellate cells, which are cultured together as microtissues in a perfused three‐dimensional microphysiological system (MPS). The microtissues were cultured in medium containing free fatty acids for at least 2 weeks, to induce a NASH‐like phenotype. The co‐culture microtissues within the MPS display a NASH‐like phenotype, showing key features of the disease including hepatic fat accumulation, the production of an inflammatory milieu, and the expression of profibrotic markers. Addition of lipopolysaccharide resulted in a more pro‐inflammatory milieu. In the model, obeticholic acid ameliorated the NASH phenotype. Microtissues were formed from both wild‐type and patatin‐like phospholipase domain containing 3 (PNPLA3) I148M mutant hepatic stellate cells. Stellate cells carrying the mutation enhanced the overall disease state of the model and in particular produced a more pro‐inflammatory milieu. Conclusion: The MPS model displays a phenotype akin to advanced NAFLD or NASH and has utility as a tool for exploring mechanisms underlying the disease. Furthermore, we demonstrate that in co‐culture the PNPLA3 I148M mutation alone can cause hepatic stellate cells to enhance the overall NASH disease phenotype

Towards More Predictive, Physiological and Animal-free In Vitro Models: Advances in Cell and Tissue Culture 2020 Conference Proceedings

Experimental systems that faithfully replicate human physiology at cellular, tissue and organ level are crucial to the development of efficacious and safe therapies with high success rates and low cost. The development of such systems is challenging and requires skills, expertise and inputs from a diverse range of experts, such as biologists, physicists, engineers, clinicians and regulatory bodies. Kirkstall Limited, a biotechnology company based in York, UK, organised the annual conference, Advances in Cell and Tissue Culture (ACTC), which brought together people having a variety of expertise and interests, to present and discuss the latest developments in the field of cell and tissue culture and in vitro modelling. The conference has also been influential in engaging animal welfare organisations in the promotion of research, collaborative projects and funding opportunities. This report describes the proceedings of the latest ACTC conference, which was held virtually on 30th September and 1st October 2020, and included sessions on in vitro models in the following areas: advanced skin and respiratory models, neurological disease, cancer research, advanced models including 3-D, fluid flow and co-cultures, diabetes and other age-related disorders, and animal-free research. The roundtable session on the second day was very interactive and drew huge interest, with intriguing discussion taking place among all participants on the theme of replacement of animal models of disease

Transmission patterns of smallpox: systematic review of natural outbreaks in Europe and North America since World War II

BACKGROUND: Because smallpox (variola major) may be used as a biological weapon, we reviewed outbreaks in post-World War II Europe and North America in order to understand smallpox transmission patterns. METHODS: A systematic review was used to identify papers from the National Library of Medicine, Embase, Biosis, Cochrane Library, Defense Technical Information Center, WorldCat, and reference lists of included publications. Two authors reviewed selected papers for smallpox outbreaks. RESULTS: 51 relevant outbreaks were identified from 1,389 publications. The median for the effective first generation reproduction rate (initial R) was 2 (range 0–38). The majority outbreaks were small (less than 5 cases) and contained within one generation. Outbreaks with few hospitalized patients had low initial R values (median of 1) and were prolonged if not initially recognized (median of 3 generations); outbreaks with mostly hospitalized patients had higher initial R values (median 12) and were shorter (median of 3 generations). Index cases with an atypical presentation of smallpox were less likely to have been diagnosed with smallpox; outbreaks in which the index case was not correctly diagnosed were larger (median of 27.5 cases) and longer (median of 3 generations) compared to outbreaks in which the index case was correctly diagnosed (median of 3 cases and 1 generation). CONCLUSION: Patterns of spread during Smallpox outbreaks varied with circumstances, but early detection and implementation of control measures is a most important influence on the magnitude of outbreaks. The majority of outbreaks studied in Europe and North America were controlled within a few generations if detected early

Vectors in school mathematics

Vectors have several meanings in the science. Mathematicians, physicists and other scientists make use of the notion of a vector. The notions they make use of are different in different subjects. Here we present different meanings of vectors and give some hints how to understand them in different subjects of science

A mistake in definition of a limit of a function and some consequences

Many times our students make some errors in definitions, especially when we must apply some quantifiers. The definition of a limit is one of the definition with many quantifiers, so one can observe many mistakes in it. We want to present one of possible mistakes and show how to improve the understanding of this difficult but one of most important notions

Quantitative Assessment of Population Variability in Hepatic Drug Metabolism Using a Perfused Three-Dimensional Human Liver Microphysiological System

In this work, we first describe the population variability in hepatic drug metabolism using cryopreserved hepatocytes from five different donors cultured in a perfused three-dimensional human liver microphysiological system, and then show how the resulting data can be integrated with a modeling and simulation framework to accomplish in vitro-in vivo translation. For each donor, metabolic depletion profiles of six compounds (phenacetin, diclofenac, lidocaine, ibuprofen, propranolol, and prednisolone) were measured, along with metabolite formation, mRNA levels of 90 metabolism-related genes, and markers of functional viability [lactate dehydrogenase (LDH) release, albumin, and urea production]. Drug depletion data were analyzed with mixed-effects modeling. Substantial interdonor variability was observed with respect to gene expression levels, drug metabolism, and other measured hepatocyte functions. Specifically, interdonor variability in intrinsic metabolic clearance ranged from 24.1% for phenacetin to 66.8% for propranolol (expressed as coefficient of variation). Albumin, urea, LDH, and cytochrome P450 mRNA levels were identified as significant predictors of in vitro metabolic clearance. Predicted clearance values from the liver microphysiological system were correlated with the observed in vivo values. A population physiologically based pharmacokinetic model was developed for lidocaine to illustrate the translation of the in vitro output to the observed pharmacokinetic variability in vivo. Stochastic simulations with this model successfully predicted the observed clinical concentration-time profiles and the associated population variability. This is the first study of population variability in drug metabolism in the context of a microphysiological system and has important implications for the use of these systems during the drug development process.United States. Defense Advanced Research Projects Agency. Microphysiological Systems Program (Grant W911NF-12-2-0039)National Institutes of Health (U.S.). Microphysiological Systems Program (Grant 4-UH3-TR000496-03