440 research outputs found
Exploring scientists’ perceptions of citizen science for public engagement with science
It is often assumed that citizen science is inherently participatory in nature. However, citizen science projects exist along a continuum from data contribution to full co-creation. We invited 19 biologists to explore their conceptions of citizen science. Almost all participants defined citizen science as involving non-scientists in data collection. This definition acted as a barrier for scientists who did not see how citizen science could suit their research objectives. While interviewees perceived many societal and experiential benefits of contributory citizen science, deliberate design is needed to realise the full potential of citizen science for public engagemen
The difficult, divisive and disruptive heritage of the Queensland Native Mounted Police
The colonial history of nineteenth-century Queensland was arguably dominated by the actions of the Native Mounted Police, Australia’s most punitive native policing force. The centrality of the Native Mounted Police to the sustained economic success of Queensland for over half a century, and their widespread, devastating effects on Aboriginal societies across the colony, have left a complex legacy. For non-Indigenous Queenslanders, a process of obscuring the Native Mounted Police began perhaps as soon as a detachment was removed from an area, reflected today in the minimisation of the Native Mounted Police in official histories and their omission from non-Indigenous heritage lists. In contrast, the Aboriginal Cultural Heritage Database preserves several elements of frontier conflict and Native Mounted Police presence, giving rise to parallel state-level narratives, neither of which map directly onto local and regional memory. This highlights potential issues for formal processes of truth-telling relating to frontier conflict that have recently been initiated by the Queensland and Federal Governments. Of particular concern is the form that such a process might adopt. Drawing on a 4-year project to document the workings of the Queensland Native Mounted Police through archival, archaeological and oral historical sources, we suggest that this conflicted and conflictual heritage can best be bridged through empathetic truth-telling, using Rothberg’s notion of the implicated subject to consider contemporary contexts of responsibility and connect present-day Queenslanders with this difficult, divisive and disruptive past
Low viral doses are sufficient to infect cottontail rabbits with avian influenza A virus
Influenza A viruses (IAVs) have been reported in wild lagomorphs in environments where they share resources with waterfowl. Recent studies have conclusively shown that a North American lagomorph, cottontail rabbits (Sylvilagus sp.), become infected following exposure to IAVs and can shed significant quantities of virus. However, the minimum infectious dose and the efficiency of various routes of infection have not been evaluated. Thirty-six cottontail rabbits were used in a dose response study assessing both the oral and nasal routes of infection. The nasal route of infection proved to be the most efficient, as all cottontail rabbits shed viral RNA following inoculation with doses as low as 102 EID50. The oral route of infection was less efficient, but still produced infection rates of ≥ 50% at relatively low doses (i.e., 103 and 104 EID50). These results suggest that cottontail rabbits are highly susceptible to IAVs at low exposure doses that have been routinely observed in environments contaminated by waterfowl. Furthermore, this study supports earlier observations that cottontail rabbits may pose a biosecurity risk to poultry operations, as a virus-contaminated water source or contaminated environment, even at low viral titers, could be sufficient to initiate viral replication in cottontail rabbits
Shedding Light on Avian Influenza H4N6 Infection in Mallards: Modes of Transmission and Implications for Surveillance
Background: Wild mallards (Anas platyrhychos) are considered one of the primary reservoir species for avian influenza viruses (AIV). Because AIV circulating in wild birds pose an indirect threat to agriculture and human health, understanding the ecology of AIV and developing risk assessments and surveillance systems for prevention of disease is critical.
Methodology/Principal Findings: In this study, mallards were experimentally infected with an H4N6 subtype of AIV by oral inoculation or contact with an H4N6 contaminated water source. Cloacal swabs, oropharyngeal swabs, fecal samples, and water samples were collected daily and tested by real-time RT-PCR (RRT-PCR) for estimation of viral shedding. Fecal samples had significantly higher virus concentrations than oropharyngeal or cloacal swabs and 6 month old ducks shed significantly more viral RNA than 3 month old ducks regardless of sample type. Use of a water source contaminated by AIV infected mallards, was sufficient to transmit virus to naïve mallards, which shed AIV at higher or similar levels as orally-inoculated ducks.
Conclusions: Bodies of water could serve as a transmission pathway for AIV in waterfowl. For AIV surveillance purposes, water samples and fecal samples appear to be excellent alternatives or additions to cloacal and oropharyngeal swabbing. Furthermore, duck age (even within hatch-year birds) may be important when interpreting viral shedding results from experimental infections or surveillance. Differential shedding among hatch-year mallards could affect prevalence estimates, modeling of AIV spread, and subsequent risk assessments
Phosphorylation of Eukaryotic Initiation Factor 2-α in Response to Endoplasmic Reticulum and Nitrosative Stress in the human protozoan parasite, Entamoeba histolytica
Entamoeba histolytica is an intestinal parasite infecting over 50 million people worldwide and is the causative agent of amebic dysentery and amoebic liver abscess. In the human host, E. histolytica experiences stress brought on by nutrient deprivation and the host immune response. To be a successful parasite, E. histolytica must counter the stress; therefore, understanding the stress response may uncover new drug targets. In many systems, the stress response includes down-regulation of protein translation, which is regulated by phosphorylation of eukaryotic initiation factor (eIF-2α). Previous work has demonstrated that phosphorylation of the E. histolytica eIF-2α (EheIF-2α) increases significantly when exposed to long-term serum starvation, oxidative stress, and long-term heat shock. However, the effects of reagents that are known to induce nitrosative or endoplasmic reticulum (ER) stresses, on EheIF-2α have yet to be evaluated. Nitrosative stress is part of the host's immune response and ER stress can be caused by several physiological or pathological factors. We treated E. histolytica cells with various reagents known to induce nitrosative stress (DPTA-NONOate and SNP) or ER stress (BFA and DTT). We examined the morphology of the ER, tracked phosphorylation of EheIF-2α, and assessed protein translation in control and stressed cells. While all four stress-inducing reagents caused a global reduction in protein translation, only DTT was capable of also inducing changes in the morphology of the ER (consistent with ER stress) and phosphorylation of EheIF-2α. This suggests that DTT authentically induces ER stress in E. histolytica and that this stress is managed by the eIF-2α-based system. This was supported by the observation that cells expressing a non-phosphorylatable version of eIF-2α were also highly sensitive to DTT-stress. Since protein translation decreased in the absence of phosphorylation of eIF-2α (after treatment with DPTA-NONOate, SNP or BFA), the data also indicate that there are alternative protein-translational control pathways in E. histolytica. Overall, our study further illuminates the stress response to nitrosative stress and ER stress in E. histolytica
Persistence of maternal antibodies to influenza A virus among captive mallards (\u3ci\u3eAnas platyrhynchos\u3c/i\u3e)
Wild waterfowl are maintenance hosts of most influenza A virus (IAV) subtypes and are often the subjects of IAV surveillance and transmission models. While maternal antibodies have been detected in yolks and in nestlings for a variety of wild bird species and pathogens, the persistence of maternal antibodies to IAVs in mallard ducklings (Anas platyrhynchos) has not been previously investigated. Nonetheless, this information is important for a full understanding of IAV transmission dynamics because ducklings protected by maternal antibodies may not be susceptible to infection. In this study, we examined the transfer of IAV-specific maternal antibodies to ducklings. Blood samples were collected approximately every five days from ducklings hatched from hens previously infected with an H6 strain of IAV. Serum samples were tested for antibodies to IAV by an enzyme-linked immunosorbent assay. The median persistence of maternal antibodies in ducklings was 12.5 days (range: 4-33 days) post-hatch. The majority of ducklings (71%) had detectable maternal antibodies from 4 to 17 days post-hatch, while a small subset of individuals (29%) had detectable maternal antibodies for up to 21-33 days post-hatch. Antibody concentrations in hens near the time of egg laying were correlated with maternal antibody concentrations in the initial blood sample collected from ducklings (0-4 days post-hatch). Knowledge of the duration of maternal antibodies in ducklings will aid in the interpretation of IAV serological surveillance results and in the modeling of IAV transmission dynamics in waterfowl
Experimental infections of Norway rats with avian‑derived low‑pathogenic influenza A viruses
Influenza A viruses (IAVs) are a public-health, veterinary, and agricultural concern. Although wild birds are considered the primary reservoir hosts for most IAVs, wild-bird IAV strains are known to spill over into poultry, domestic or wild mammals, and humans. Occasionally, spillover events may result in adaptation or reassortment with other strains. Moreover, some IAV strains found in wild waterfowl mutate into highly pathogenic forms in poultry, causing tremendous economic losses. When domestic animals, wildlife, and humans dwell in close proximity to each other, such as may be the case with agricultural operations, wildlife may represent a potential risk for interspecies pathogen transmission. Understanding the pathways through which IAV strains could spillover from waterfowl reservoirs into humans and domestic animals is important for limiting the spread of IAVs, as well as developing biosecurity and containment procedures in livestock and poultry production. Experimental studies of common wild mammals in the U.S., bank voles (Myodes glareolus) in Europe and Asia, and black rats (Rattus rattus) in Japan have shown varying degrees of IAV susceptibility and/or transmission in these synanthropic species. While Norway rats (Rattus norvegicus) are ubiquitous throughout rural and urban areas of the world and have the ability to range between these areas, only limited investigations of this species have been conducted, and their role in IAV transmission has not been clearly established. The main objective of this study was to further characterize IAV infection in Norway rats using IAV strains derived from poultry and wild water birds
Experiences of Women of Color with a Nurse Patient Navigation Program for Linkage and Engagement in HIV Care
Patient navigation, a patient-centered model of care coordination focused on reducing barriers to care, is an emerging strategy for linking patients to and retaining them in HIV care. The Guide to Healing Program (G2H), implemented at the Infectious Diseases Clinic at UNC Chapel Hill, provided patient navigation to women of color (WOC) new to or re-engaging in HIV care through a ‘nurse guide’ with mental health training and experience. The purpose of this study was to qualitatively explore patients' experiences working with the nurse guide. Twenty-one semi-structured telephone interviews with G2H participants were conducted. Interviews were transcribed and thematic analysis was utilized to identify patterns and themes in the data. Women's experiences with the nurse guide were overwhelmingly positive. They described the nurse guide teaching them critical information and skills, facilitating access to resources, and conveying authentic kindness and concern. The findings suggest that a properly trained nurse in this role can provide critical medical and psychosocial support in order to eliminate barriers to engagement in HIV care, and successfully facilitate patient HIV self-management. The nurse guide model represents a promising approach to patient navigation for WOC living with HIV
Extended Viral Shedding of a Low Pathogenic Avian Influenza Virus by Striped Skunks (Mephitis mephitis)
Background: Striped skunks (Mephitis mephitis) are susceptible to infection with some influenza A viruses. However, the viral shedding capability of this peri-domestic mammal and its potential role in influenza A virus ecology are largely undetermined.
Methodology/Principal Findings: Striped skunks were experimentally infected with a low pathogenic (LP) H4N6 avian influenza virus (AIV) and monitored for 20 days post infection (DPI). All of the skunks exposed to H4N6 AIV shed large quantities of viral RNA, as detected by real-time RT-PCR and confirmed for live virus with virus isolation, from nasal washes and oral swabs (maximum #106.02 PCR EID50 equivalent/mL and #105.19 PCR EID50 equivalent/mL, respectively). Some evidence of potential fecal shedding was also noted. Following necropsy on 20 DPI, viral RNA was detected in the nasal turbinates of one individual. All treatment animals yielded evidence of a serological response by 20 DPI.
Conclusions/Significance: These results indicate that striped skunks have the potential to shed large quantities of viral RNA through the oral and nasal routes following exposure to a LP AIV. Considering the peri-domestic nature of these animals, along with the duration of shedding observed in this species, their presence on poultry and waterfowl operations could influence influenza A virus epidemiology. For example, this species could introduce a virus to a naive poultry flock or act as a trafficking mechanism of AIV to and from an infected poultry flock to naive flocks or wild bird populations
High-definition colonoscopy versus Endocuff versus EndoRings versus Full-Spectrum Endoscopy for adenoma detection at colonoscopy: a multicenter randomized trial
Background
Devices used to improve polyp detection during colonoscopy have seldom been compared with each other.
Methods
We performed a 3-center prospective randomized trial comparing high-definition (HD) forward-viewing colonoscopy alone to HD with Endocuff to HD with EndoRings to the Full Spectrum Endoscopy (FUSE) system. Patients were age ≥50 years and had routine indications and intact colons. The study colonoscopists were all proven high-level detectors. The primary endpoint was adenomas per colonoscopy (APC)
Results
Among 1,188 patients who completed the study, APC with Endocuff (APC Mean ± SD 1.82 ± 2.58), EndoRings (1.55 ± 2.42), and standard HD colonoscopy (1.53 ± 2.33) were all higher than FUSE (1.30 ± 1.96,) (p<0.001 for APC). Endocuff was higher than standard HD colonoscopy for APC (p=0.014) . Mean cecal insertion times with FUSE (468 ± 311 seconds) and EndoRings (403 ± 263 seconds) were both longer than with Endocuff (354 ± 216 seconds) (p=0.006 and 0.018, respectively).
Conclusions
For high-level detectors at colonoscopy, forward-viewing HD instruments dominate the FUSE system, indicating that for these examiners image resolution trumps angle of view. Further, Endocuff is a dominant strategy over EndoRings and no mucosal exposure device on a forward-viewing HD colonoscope
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