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Multispectral imaging – the acquisition of spatially contiguous imaging data in a modest number (~3–16) of spectral bandpasses – has proven to be a powerful technique for augmenting panchromatic imaging observations on Mars focused on geologic and/or atmospheric context. Specifically, multispectral imaging using modern digital CCD photodetectors and narrowband filters in the 400–1100 nm wavelength region on the Mars Pathfinder, Mars Exploration Rover, Phoenix, and Mars Science Laboratory missions has provided new information on the composition and mineralogy of fine-grained regolith components (dust, soils, sand, spherules, coatings), rocky surface regions (cobbles, pebbles, boulders, outcrops, and fracture-filling veins), meteorites, and airborne dust and other aerosols. Here we review recent scientific results from Mars surface-based multispectral imaging investigations, including the ways that these observations have been used in concert with other kinds of measurements to enhance the overall scientific return from Mars surface missions.
Animal disease events can lead to international trade restrictions which can vary in duration, products included, and geographical extent. Accounting for multilateral resistance between trading partners, a general gravity model of trade is estimated with a Hausman-Taylor and a Hausman-Taylor seemingly unrelated estimator to evaluate the trade quantity impact by commodity resulting from highly pathogenic poultry disease events in 24 exporting markets. Commodity specific results show that quantity traded and products demanded during a disease event differ by commodities. Understanding these impacts can better prepare exporters for potential changes in trade quantity given a disease event.
There is an established link between birth parameters and risk of adult-onset cancers. The Developmental Origins of Health and Disease concept provides potential underlying mechanisms for such associations, including intrauterine exposure to endogenous hormones (androgens and estrogens), insulin-like growth factors, etc. However, there is conflicting evidence on the association between birth parameters and the cancer mortality risk. Therefore, we aimed to review and analyse the available data on the association linking birth weight and birth length with cancer mortality. Eleven studies were identified, published until April 2019. A significant association between birth weight and the prognosis of cancer (overall) was found (relative risk, RR 1.06, 95% confidence interval, CI: 1.01, 1.11), with low heterogeneity (I2 = 27.7%). In addition, higher birth weight was associated with poorer prognosis of prostate cancer (RR 1.21, 95% CI: 1.02, 1.44). However, the association of birth weight with breast cancer mortality risk in women was not significant (RR 1.16, 95% CI: 0.93, 1.44), which might be due to high statistical heterogeneity (I2 = 67.9%). Birth length was not associated with cancer mortality risk (RR 1.0, 95% CI: 0.90–1.11). It might be inferred that birth parameters are not associated with cancer mortality as strongly as with the risk of developing cancer. Also, the association between birth parameters and cancer mortality risk is not uniform and varies according to its subtypes, and study characteristics/design. This highlights the need for further prospective studies.
We studied the association between chlorhexidine gluconate (CHG) concentration on skin and resistant bacterial bioburden. CHG was almost always detected on the skin, and detection of methicillin-resistant Staphylococcus aureus, carbapenem-resistant Enterobacteriaceae, and vancomycin-resistant Enterococcus on skin sites was infrequent. However, we found no correlation between CHG concentration and bacterial bioburden.
Human and animal research both operate within established standards. In the United States, criticism of the human research environment and recorded abuses of human research subjects served as the impetus for the establishment of the National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research, and the resulting Belmont Report. The Belmont Report established key ethical principles to which human research should adhere: respect for autonomy, obligations to beneficence and justice, and special protections for vulnerable individuals and populations. While current guidelines appropriately aim to protect the individual interests of human participants in research, no similar, comprehensive, and principled effort has addressed the use of (nonhuman) animals in research. Although published policies regarding animal research provide relevant regulatory guidance, the lack of a fundamental effort to explore the ethical issues and principles that should guide decisions about the potential use of animals in research has led to unclear and disparate policies. Here, we explore how the ethical principles outlined in the Belmont Report could be applied consistently to animals. We describe how concepts such as respect for autonomy and obligations to beneficence and justice could be applied to animals, as well as how animals are entitled to special protections as a result of their vulnerability.
Translocation and rehabilitation programmes are critical tools for wildlife conservation. These methods achieve greater impact when integrated in a combined strategy for enhancing population or ecosystem restoration. During 2002–2016 we reared 37 orphaned southern sea otter Enhydra lutris nereis pups, using captive sea otters as surrogate mothers, then released them into a degraded coastal estuary. As a keystone species, observed increases in the local sea otter population unsurprisingly brought many ecosystem benefits. The role that surrogate-reared otters played in this success story, however, remained uncertain. To resolve this, we developed an individual-based model of the local population using surveyed individual fates (survival and reproduction) of surrogate-reared and wild-captured otters, and modelled estimates of immigration. Estimates derived from a decade of population monitoring indicated that surrogate-reared and wild sea otters had similar reproductive and survival rates. This was true for males and females, across all ages (1–13 years) and locations evaluated. The model simulations indicated that reconstructed counts of the wild population are best explained by surrogate-reared otters combined with low levels of unassisted immigration. In addition, the model shows that 55% of observed population growth over this period is attributable to surrogate-reared otters and their wild progeny. Together, our results indicate that the integration of surrogacy methods and reintroduction of juvenile sea otters helped establish a biologically successful population and restore a once-impaired ecosystem.
Laboratory-identified bloodstream infections (LAB-ID BSIs) in recently discharged patients are likely to be classified as healthcare-associated community-onset (HCA-CO) infections, even though they may represent hospital-onset (HO) infections. A review of LAB-ID BSIs among patients discharged within 14 days revealed that 109 of 756 cases (14.4%) were HO infections. The BSI risk being misclassified as HCA CO may underestimate the hospital infection risk.
Moral reasoning and decision making help guide behavior and facilitate interpersonal relationships. Accounts of morality that position commonsense psychology as the foundation of moral development, (i.e., rationalist theories) have dominated research in morality in autism spectrum disorder (ASD). Given the well-documented differences in commonsense psychology among autistic individuals, researchers have investigated whether the development and execution of moral judgement and reasoning differs in this population compared with neurotypical individuals. In light of the diverse findings of investigations of moral development and reasoning in ASD, a summation and critical evaluation of the literature could help make sense of what is known about this important social-cognitive skill in ASD. To that end, we conducted a systematic review of the literature investigating moral decision making among autistic children and adults. Our search identified 29 studies. In this review, we synthesize the research in the area and provide suggestions for future research. Such research could include the application of an alternative theoretical framework to studying morality in autism spectrum disorder that does not assume a deficits-based perspective.
Sugar-sweetened beverage (SSB) consumption in early childhood is a public health concern. Adequate hydration in early childhood is also important. We developed a national research agenda to improve beverage consumption patterns among 0–5-year-olds. This article focuses on the process used to develop this research agenda.
A mixed methods, multi-step process was used to develop the research agenda, including: (i) a scientific advisory committee; (ii) systematic reviews on strategies to reduce SSB consumption and increase water access and consumption; (iii) two stakeholder surveys to first identify and then rank strategies to reduce SSB consumption and increase water access and consumption; (iv) key informant interviews to better understand determinants of beverage consumption and strategies to improve beverage consumption patterns among high-risk groups; (v) an in-person convening with experts; and (vi) developing the final research agenda.
This process included research and stakeholders from across the United States.
A total of 276 participants completed survey 1 and 182 participants completed survey 2. Key informant interviews were conducted with 12 stakeholders. Thirty experts attended the convening, representing academia, government, and non-profit sectors.
Thirteen key issue areas and 59 research questions were developed. Priority topics were beverage consumption recommendations, fruit-flavoured drink consumption, interventions tailored to high-risk groups, and family engagement in childcare.
This research agenda lays the groundwork for research efforts to improve beverage patterns of young children. The methods used can be a template to develop research agendas for other public health issues.
The spread of the Zika virus (ZIKV) in the Americas led to large outbreaks across the region and most of the Southern hemisphere. Of greatest concern were complications following acute infection during pregnancy. At the beginning of the outbreak, the risk to unborn babies and their clinical presentation was unclear. This report describes the methods and results of the UK surveillance response to assess the risk of ZIKV to children born to returning travellers. Established surveillance systems operating within the UK – the paediatric and obstetric surveillance units for rare diseases, and national laboratory monitoring – enabled rapid assessment of this emerging public health threat. A combined total of 11 women experiencing adverse pregnancy outcomes after possible ZIKV exposure were reported by the three surveillance systems; five miscarriages, two intrauterine deaths and four children with clinical presentations potentially associated with ZIKV infection. Sixteen women were diagnosed with ZIKV during pregnancy in the UK. Amongst the offspring of these women, there was unequivocal laboratory evidence of infection in only one child. In the UK, the number and risk of congenital ZIKV infection for travellers returning from ZIKV-affected countries is very small.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Dense granular flows can spontaneously self-channelise by forming a pair of parallel-sided static levees on either side of a central flowing channel. This process prevents lateral spreading and maintains the flow thickness, and hence mobility, enabling the grains to run out considerably further than a spreading flow on shallow slopes. Since levees commonly form in hazardous geophysical mass flows, such as snow avalanches, debris flows, lahars and pyroclastic flows, this has important implications for risk management in mountainous and volcanic regions. In this paper an avalanche model that incorporates frictional hysteresis, as well as depth-averaged viscous terms derived from the
-rheology, is used to quantitatively model self-channelisation and levee formation. The viscous terms are crucial for determining a smoothly varying steady-state velocity profile across the flowing channel, which has the important property that it does not exert any shear stresses at the levee–channel interfaces. For a fixed mass flux, the resulting boundary value problem for the velocity profile also uniquely determines the width and height of the channel, and the predictions are in very good agreement with existing experimental data for both spherical and angular particles. It is also shown that in the absence of viscous (second-order gradient) terms, the problem degenerates, to produce plug flow in the channel with two frictionless contact discontinuities at the levee–channel margins. Such solutions are not observed in experiments. Moreover, the steady-state inviscid problem lacks a thickness or width selection mechanism and consequently there is no unique solution. The viscous theory is therefore a significant step forward. Fully time-dependent numerical simulations to the viscous model are able to quantitatively capture the process in which the flow self-channelises and show how the levees are initially emplaced behind the flow head. Both experiments and numerical simulations show that the height and width of the channel are not necessarily fixed by these initial values, but respond to changes in the supplied mass flux, allowing narrowing and widening of the channel long after the initial front has passed by. In addition, below a critical mass flux the steady-state solutions become unstable and time-dependent numerical simulations are able to capture the transition to periodic erosion–deposition waves observed in experiments.
Shallow granular avalanches on slopes close to repose exhibit hysteretic behaviour. For instance, when a steady-uniform granular flow is brought to rest it leaves a deposit of thickness
on a rough slope inclined at an angle
to the horizontal. However, this layer will not spontaneously start to flow again until it is inclined to a higher angle
, or the thickness is increased to
. This simple phenomenology leads to a rich variety of flows with co-existing regions of solid-like and fluid-like granular behaviour that evolve in space and time. In particular, frictional hysteresis is directly responsible for the spontaneous formation of self-channelized flows with static levees, retrogressive failures as well as erosion–deposition waves that travel through the material. This paper is motivated by the experimental observation that a travelling-wave develops, when a steady uniform flow of carborundum particles on a bed of larger glass beads, runs out to leave a deposit that is approximately equal to
. Numerical simulations using the friction law originally proposed by Edwards et al. (J. Fluid Mech., vol. 823, 2017, pp. 278–315) and modified here, demonstrate that there are in fact two travelling waves. One that marks the trailing edge of the steady-uniform flow and another that rapidly deposits the particles, directly connecting the point of minimum dynamic friction (at thickness
) with the deposited layer. The first wave moves slightly faster than the second wave, and so there is a slowly expanding region between them in which the flow thins and the particles slow down. An exact inviscid solution for the second travelling wave is derived and it is shown that for a steady-uniform flow of thickness
it produces a deposit close to
for all inclination angles. Numerical simulations show that the two-wave structure deposits layers that are approximately equal to
for all initial thicknesses. This insensitivity to the initial conditions implies that
is a universal quantity, at least for carborundum particles on a bed of larger glass beads. Numerical simulations are therefore able to capture the complete experimental staircase procedure, which is commonly used to determine the
curves by progressively increasing the inclination of the chute. In general, however, the deposit thickness may depend on the depth of the flowing layer that generated it, so the most robust way to determine
is to measure the deposit thickness from a flow that was moving at the minimum steady-uniform velocity. Finally, some of the pathologies in earlier non-monotonic friction laws are discussed and it is explicitly shown that with these models either steadily travelling deposition waves do not form or they do not leave the correct deposit depth
In 2008, for the first time in the history of this country, a black woman became First Lady of the United States. During Barack Obama's presidency, Michelle Obama was ever present in the public eye for her advocacy on issues related to health, military families, education, and for promoting the interests of women and girls. This article contributes to ongoing scholarly discourse, as well as extensive media coverage and analysis, regarding Obama's role as wife and first lady by critically examining how the particular model of motherhood she embraced and exhibited, a model firmly rooted in the black American community, was designed to challenge negative stereotypes of black women, maternity, and families. We address the following questions in this work: How did Obama's identity as a black woman influence the policies she championed as first lady? Does Obama's mothering relate to stereotypes of black mothers and help (re)define black motherhood, and if so, how? What does it mean to be a black mater gentis or mother of the nation? Drawing on her speeches and policy initiatives, we reveal how Michelle Obama defied dominant and oppressive stereotypes of black women and mothers while simultaneously (re)defining black womanhood and motherhood for the nation.
Despite United States national learning objectives referencing research fundamentals and the critical appraisal of medical literature, many paramedic programs are not meeting these objectives with substantive content.
The objective was to develop and implement a journal club educational module for paramedic training programs, which is all-inclusive and could be distributed to Emergency Medical Services (EMS) educators and EMS medical directors to use as a framework to adapt to their program.
Four two-hour long journal club sessions were designed. First, the educator provided students with four types of articles on a student-chosen topic and discussed differences in methodology and structures. Next, after a lecture about peer-review, students used search engines to verify references of a trade magazine article. Third, the educator gave a statistics lecture and critiqued the results section of several articles found by students on a topic. Finally, students found an article on a topic of personal interest and presented it to their classmates, as if telling their paramedic partner about it at work. Before and after the series, students from two cohorts (2017, 2018) completed a survey with questions about demographics and perceptions of research. Students from one cohort (2017) received a follow-up survey one year later.
For the 2016 cohort, 13 students participated and provided qualitative feedback. For the 2017 and 2018 cohorts, 33 students participated. After the series, there was an increased self-reported ability to find, evaluate, and apply medical research articles, as well as overall positive trending opinions of participating in and the importance of prehospital research. This ability was demonstrated by every student during the final journal club session. McNemar’s and Related-Samples Cochran’s Q testing of questionnaire responses suggested a statistically significant improvement in student approval of exceptions from informed consent.
The framework for this paramedic journal club series could be adapted by EMS educators and medical directors to enable paramedics to search for, critically appraise, and discuss the findings of medical literature.