Bridging Physics and Biology Teaching through Modeling

As the frontiers of biology become increasingly interdisciplinary, the physics education community has engaged in ongoing efforts to make physics classes more relevant to life sciences majors. These efforts are complicated by the many apparent differences between these fields, including the types of systems that each studies, the behavior of those systems, the kinds of measurements that each makes, and the role of mathematics in each field. Nonetheless, physics and biology are both sciences that rely on observations and measurements to construct models of the natural world. In the present theoretical article, we propose that efforts to bridge the teaching of these two disciplines must emphasize shared scientific practices, particularly scientific modeling. We define modeling using language common to both disciplines and highlight how an understanding of the modeling process can help reconcile apparent differences between the teaching of physics and biology. We elaborate how models can be used for explanatory, predictive, and functional purposes and present common models from each discipline demonstrating key modeling principles. By framing interdisciplinary teaching in the context of modeling, we aim to bridge physics and biology teaching and to equip students with modeling competencies applicable across any scientific discipline.Comment: 10 pages, 2 figures, 3 table

Clinical practice guidelines for depression in young people

The document attached has been archived with permission from the editor of the Medical Journal of Australia. An external link to the publisher’s copy is included. See page 4 of PDF for this item.Jon N Jureidini and Anne L Tonki

Operationalising a model framework for consumer and community participation in health and medical research

The Consumers' Health Forum of Australia and the National Health and Medical Research Council has recently developed a Model Framework for Consumer and Community Participation in Health and Medical Research in order to better align health and medical research with community need, and improve the impact of research. Model frameworks may have little impact on what goes on in practice unless relevant organisations actively make use of them. Philanthropic and government bodies have reported involving consumers in more meaningful or collaborative ways of late. This paper describes how a large charity organisation, which funds a significant proportion of Australian cancer research, operationalised the model framework using a unique approach demonstrating that it is both possible and reasonable for research to be considerate of public values

Future beam experiments in the magnetosphere with plasma contactors: How do we get the charge off the spacecraft?

The idea of using a high‐voltage electron beam with substantial current to actively probe magnetic field line connectivity in space has been discussed since the 1970s. However, its experimental realization onboard a magnetospheric spacecraft has never been accomplished because the tenuous magnetospheric plasma cannot provide the return current necessary to keep spacecraft charging under control. In this work, we perform Particle‐In‐Cell simulations to investigate the conditions under which a high‐voltage electron beam can be emitted from a spacecraft and explore solutions that can mitigate spacecraft charging. The electron beam cannot simply be compensated for by an ion beam of equal current, because the Child‐Langmuir space charge limit is violated under conditions of interest. On the other hand, releasing a high‐density neutral contactor plasma prior and during beam emission is critical in aiding beam emission. We show that after an initial transient controlled by the size of the contactor cloud where the spacecraft potential rises, the spacecraft potential can settle into conditions that allow for electron beam emission. A physical explanation of this result in terms of ion emission into spherical geometry from the surface of the plasma cloud is presented, together with scaling laws of the peak spacecraft potential varying the ion mass and beam current. These results suggest that a strategy where the contactor plasma and the electron beam operate simultaneously might offer a pathway to perform beam experiments in the magnetosphere.Key PointsThe contactor plasma mitigates spacecraft charging from electron beam emissionThe contactor allows ion emission over a larger, quasi‐spherical areaThe peak of the spacecraft potential is lower for larger contactor cloudsPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/112002/1/jgra51731.pd

The Effect of a Mycotoxin Deactivation Product on Growth of Juvenile Rainbow Trout Fed Distillers Dried Grains

Distillers dried grains (DDG) with solubles (DDGS) is a product that has shown potential as a protein source for some fish species, but high inclusion rates of DDGS have not always been successfully achieved for Rainbow Trout Oncorhynchus mykiss. Our objective was to determine whether inclusion of a mycotoxin deactivation product (Biofix Plus) could improve the ability of high-protein DDG (HPDDG) to replace a portion of the fish meal in diets for Rainbow Trout. The 2 × 2 factorial feeding trial examined protein source (menhaden fish meal [MFM] or HPDDG) with or without Biofix Plus. A control diet (42% digestible protein, 20% crude lipid, 25% MFM) was compared to a test diet in which HPDDG replaced 12% of the total MFM on a digestible-protein basis (24% HPDDG inclusion). Diets were fed to juvenile Rainbow Trout (initial weight: mean ± SE = 30.5 ± 1.6 g) in four replicate tanks per treatment for 9 weeks in a 15°C recirculating system. At the conclusion of the feeding trial, we observed no negative effects of fish meal replacement on growth or feed conversion ratio; no benefit of Biofix Plus supplementation was observed. These data indicate that when Rainbow Trout diets containing a high-quality DDGS product are balanced for digestible protein, lysine, methionine, and threonine, dietary fish meal levels can be successfully reduced to 13% without compromising growth and without the need for mycotoxin deactivator inclusion

A western gray whale mitigation and monitoring program for a 3-D seismic survey, Sakhalin Island, Russia

The introduction of anthropogenic sounds into the marine environment can impact some marine mammals. Impacts can be greatly reduced if appropriate mitigation measures and monitoring are implemented. This paper concerns such measures undertaken by Exxon Neftegas Limited, as operator of the Sakhalin-1 Consortium, during the Odoptu 3-D seismic survey conducted during 17 August’ September 2001. The key environmental issue was protection of the critically endangered western gray whale (Eschrichtius robustus), which feeds in summer and fall primarily in the Piltun feeding area off northeast Sakhalin Island. Existing mitigation and monitoring practices for seismic surveys in other jurisdictions were evaluated to identify best practices for reducing impacts on feeding activity by western gray whales. Two buffer zones were established to protect whales from physical injury or undue disturbance during feeding. A 1 km buffer protected all whales from exposure to levels of sound energy potentially capable of producing physical injury. A 4’ km buffer was established to avoid displacing western gray whales from feeding areas. Trained Marine Mammal Observers (MMOs) on the seismic ship Nordic Explorer had the authority to shut down the air guns if whales were sighted within these buffers

Geographic distribution and environmental risk factors of lymphoma in dogs under primary-care in the UK

OBJECTIVES: To integrate external data sources with VetCompass postcode data to explore the spatial distribution and examine potential associations with environmental risk factors in dogs diagnosed with lymphoma at primary care veterinary practices. MATERIALS AND METHODS: Cases of lymphoma were identified from electronic patient records of 455,553 dogs under primary veterinary care during 2013 in the UK. Cases were defined as either laboratory-confirmed or non-laboratory-confirmed. Disease maps at the postcode-district level were used to define the geographic distribution of lymphoma incidence and spatial clustering was explored. Environmental risk factors from external data sources were transferred to a compatible format and logistic regression modelling was used to examine associations between environmental herbicide, fungicide and radon concentrations with lymphoma. RESULTS: From the denominator population of 455,553 dogs, 279 lymphoma cases (187 with laboratory confirmation and 93 without) were identified. Heterogeneous geographic variation was observed with weak evidence of clustering around London and the south-west of England. Herbicide and fungicide exposures were weakly associated with a diagnosis of lymphoma in the univariable analysis. After accounting for the age at diagnosis and breed in the multivariable analysis, herbicide exposure was associated with a diagnosis of lymphoma. CLINICAL SIGNIFICANCE: The heterogeneous distribution of lymphoma in UK dogs provides further evidence for geographic variation of lymphoma, perhaps in part associated with underlying environmental risk factors. The results suggest an association between environmental herbicide and canine lymphoma

Low-dose arsenic compromises the immune response to influenza A infection in vivo

This paper is not subject to U.S. copyright. The definitive version was published in Environmental Health Perspectives 117 (2009): 1441–1447, doi:10.1289/ehp.0900911.Arsenic exposure is a significant worldwide environmental health concern. We recently reported that 5-week exposure to environmentally relevant levels (10 and 100 ppb) of As in drinking water significantly altered components of the innate immune response in mouse lung, which we hypothesize is an important contributor to the increased risk of lung disease in exposed human populations. We investigated the effects of As exposure on respiratory influenza A (H1N1) virus infection, a common and potentially fatal disease. In this study, we exposed C57BL/6J mice to 100 ppb As in drinking water for 5 weeks, followed by intranasal inoculation with a sublethal dose of influenza A/PuertoRico/8/34 (H1N1) virus. Multiple end points were assessed postinfection. Arsenic was associated with a number of significant changes in response to influenza, including an increase in morbidity and higher pulmonary influenza virus titers on day 7 postinfection. We also found many alterations in the immune response relative to As-unexposed controls, including a decrease in the number of dendritic cells in the mediastinal lymph nodes early in the course of infection. Our data indicate that chronic As exposure significantly compromises the immune response to infection. Alterations in response to repeated lung infection may also contribute to other chronic illnesses, such as bronchiectasis, which is elevated by As exposure in epidemiology studies.This work was supported by grant P42 ES007373 from the National Institute of Environmental Health Sciences [J.W.H.; Superfund Basic Research Program (SBRP) Project 2]. C.D.K. was supported by a graduate fellowship from P42 ES007373 (SBRP, Training Core) and by National Institutes of Health predoctoral fellowship T32-DF007301

A Revised Forensic Process for Aligning the Investigation Process with the Design of Forensic-Enabled Cloud Services

© Springer Nature Switzerland AG 2020. The design and implementation of cloud services, without taking under consideration the forensic requirements and the investigation process, makes the acquisition and examination of data, complex and demanding. The evidence gathered from the cloud may not become acceptable and admissible in the court. A literature gap in supporting software engineers so as to elicit and model forensic-related requirements exists. In order to fill the gap, software engineers should develop cloud services in a forensically sound manner. In this paper, a brief description of the cloud forensic-enabled framework is presented (adding some new elements) so as to understand the role of the design of forensic-enabled cloud services in a cloud forensic investigation. A validation of the forensic requirements is also produced by aligning the stages of cloud forensic investigation process with the framework’s forensic requirements. In this way, on one hand, a strong relationship is built between these two elements and emphasis is given to the role of the forensic requirements and their necessity in supporting the investigation process. On the other hand, the alignment assists towards the identification of the degree of the forensic readiness of a cloud service against a forensic investigation