1,456 research outputs found
Distribution and biogeography of the Alaskan hare (Lepus othus)
Thesis (M.S.) University of Alaska Fairbanks, 2016The Alaskan Hare (Lepus othus Merriam 1900) is the largest lagomorph in North America but remains one of the most poorly studied terrestrial mammals on the continent. Its current distribution is restricted to western Alaska south of the Brooks Range, but historical anecdotal accounts of occurrences north of the Brooks Range (the North Slope) have led to confusion over its past, present, and predicted distribution. To clarify the historical range of L. othus, we surveyed North American museum collections and georeferenced voucher specimens (Supplemental File Appendix 1.1). We also located a specimen from the North Slope of Alaska long presumed lost and whose identity had come to be questioned. The rediscovery of this missing specimen suggests the occurrence of at least one Alaskan Hare on the North Slope as recently as the late 1800s. Because unforested ecosystems such as tundra and Arctic grasslands have decreased in Alaska since the last glacial maximum, and L. othus occurs in unforested habitat, we expected to observe low genetic diversity in the mitochondrial control region of L. othus. However, with recently collected specimens from regions in Alaska that were poorly represented in the past (i.e. Alaska Peninsula, Little Diomede, and Kotzebue Sound), we discovered more genetic diversity and population structure than was found in previous studies, including similar haplotypes from the Alaska Peninsula and from eastern Russia. This suggests there may have been 2 distinct colonization events of northern hares in Alaska, or introgression from L. timidus and a mitochondrial sweep that has been restricted to the Alaska Peninsula and Bristol Bay area. Our morphological analyses of the difference between the two subspecies, L. o. othus and L. o. poadromus, were ambiguous, with principal components analysis and simple linear regression indicating the presence of a latitudinal size cline and discriminant function analysis revealing successful group assignment that is not solely based on latitude. Our research clarifies the current and recent distribution of the Alaskan Hare and reveals more genetic diversity than previously suspected in the mitochondrial control region. We also observed a new biogeographic pattern and closer mtDNA association with L. timidus, which, combined with new island specimens and observations, suggests gene flow across the Bering Strait. It also highlights the importance of maximizing sample sizes and sampling widely across a taxon’s geographic distribution
Cooperation Spillovers in Coordination Games
Motivated by problems of coordination failure observed in weak-link games, we experimentally investigate behavioral spillovers for order-statistic coordination games. Subjects play the minimum- and median-effort coordination games simultaneously and sequentially. The results show the precedent for cooperative behavior spills over from the median game to the minimum game when the games are played sequentially. Moreover, spillover occurs even when group composition changes, although the effect is not as strong. We also find that the precedent for uncooperative behavior does not spill over from the minimum game to the median game. These findings suggest guidelines for increasing cooperative behavior within organizations.coordination, order-statistic games, experiments, cooperation, minimum game, behavioral spillover
Reducing Efficiency through Communication in Competitive Coordination Games
Costless pre-play communication has been found to effectively facilitate coordination and enhance efficiency by increasing individual payoffs in games with Pareto-ranked equilibria. We report an experiment in which two groups compete in a weakest-link contest by expending costly efforts. Allowing group members to communicate before choosing efforts leads to more aggressive competition and greater coordination, but also results in substantially lower payoffs than a control treatment without communication. Our experiment thus provides evidence that communication can reduce efficiency in competitive coordination games. This contrasts sharply with experimental findings from public goods and other coordination games, where communication enhances efficiency and often leads to socially optimal outcomes.Contest; Between-group Competition; Within-group Competition; Cooperation; Coordination; Free-riding; Experiments
Entry into Winner-Take-All and Proportional-Prize Contests: An Experimental Study
This experiment compares the performance of two contest designs: a standard winnertake- all tournament with a single fixed prize, and a novel proportional-payment design in which that same prize is divided among contestants by their share of total achievement. We find that proportional prizes elicit more entry and more total achievement than the winner-take-all tournament. The proportional-prize contest performs better by limiting the degree to which heterogeneity among contestants discourages weaker entrants, without altering the performance of stronger entrants. These findings could inform the design of contests for technological and other improvements, which are widely used by governments and philanthropic donors to elicit more effort on targeted economic and technological development activities.performance pay, tournament, piece rate, tournament design, contest, experiments, risk aversion, feedback, gender
Differential regulation of different human papilloma virus variants by the POU family transcription factor Brn-3a
The Brn-3a POU family transcription factor is over-expressed in human cervical carcinoma biopsies and is able to activate expression of the human papilloma virus type 16 (HPV-16) upstream regulatory region (URR), which drives the expression of the E6 and E7 oncoproteins. Inhibition of Brn-3a expression in human cervical cancer cells inhibits HPV gene expression and reduces cellular growth and anchorage independence in vitro as well as the ability to form tumours in vivo. Here we show that Brn-3a differentially regulates different HPV-16 variants that have previously been shown to be associated with different risks of progression to cervical carcinoma. In human cervical material Brn-3a levels correlate directly with HPV E6 levels in individuals infected with a high risk variant of HPV-16 whereas this is not the case for a low risk variant. Moreover, the URRs of high and intermediate risk variants are activated by Brn-3a in transfection assays whereas the URR of a low risk variant is not. The change of one or two bases in a low risk variant URR to their equivalent in a higher risk URR can render the URR responsive to Brn-3a and vice versa. These results help explain why the specific interplay between viral and cellular factors necessary for the progression to cervical carcinoma, only occurs in a minority of those infected with HPV-16
Keeping PACE With 21st Century Healthcare: A Framework for Telehealth Research, Practice, and Program Evaluation in Occupational Therapy
The use of telehealth to deliver occupational therapy services rapidly expanded during the COVID-19 pandemic. There are frameworks to evaluate services delivered through telehealth; however, none are specific to occupational therapy. Therefore, occupational therapy would benefit from a framework to systematically evaluate components of telehealth service delivery and build evidence to demonstrate the distinct value of occupational therapy. The PACE Framework outlines four priority domains to address areas of need: (1) Population and Health Outcomes; (2) Access for All Clients; (3) Costs and Cost Effectiveness; and (4) Experiences of Clients and Occupational Therapy Practitioners. This article describes the development and expert reviewer evaluation of the PACE Framework. In addition, the PACE Framework’s domains, subdomains, and outcome measure examples are described along with future directions for implementation in occupational therapy research, practice, and program evaluation. 
Social distancing measures for COVID-19 are changing winter season
Health authorities worldwide have
adopted measures of social distancing
and movement restrictions, in addition
to other public health measures to reduce
exposure and to suppress interhuman
SARS-CoV-
2 transmission. In Italy, a
national lockdown with school closure
was introduced from March to May 2020.
From November 2020, Italy has been
divided into zones according to regional
epidemiological data, with primary
schools reopened, associated with the
mandatory use of face masks and different
levels of social distance measures. For
children with symptoms suggestive of
COVID-19, the surveillance mechanism
for the control of SARS-CoV-
2 infection
is based on the performance of a real-time
PCR on a nasopharyngeal swab. A
diagnostic test has been introduced at the
tertiary-level
university hospital, Institute
for Maternal and Child Health, IRCCS
\u201cBurlo Garofolo\u201d of Trieste, consisting of
a multiple nucleic acid amplification assay
for 13 common viral respiratory pathogens
on nasopharyngeal swab (Respiratory
Flow Chip assay (Vitro, Sevilla,
Spain), including SARS-CoV-
2, influenza
A and B, adenovirus, other coronaviruses,
parainfluenza virus 1\u20134, enteroviruses,
bocavirus, metapneumovirus, respiratory
syncytial virus (RSV), rhinoviruses, Bordetella
pertussis, Bordetella parapertussis
and Mycoplasma pneumoniae. Before
routine utilisation, international standard
quality control samples for each pathogen
were used for test validation, and no
cross-detection
was found between the
different pathogens. Criteria for testing
referral did not change during the study
period. Weekly variability of the number
of total tests performed was due to the
normal variations of acute illness. During
the last winter season, from September
2020 (week 39) to February 2021 (week
7), 1138 nasopharyngeal swabs were
tested for patients younger than 17 years
old (figure 1). No influenza A or B nor
RSV was detected during this period.
The most common pathogen was rhinovirus
(n=505), followed by adenoviruses
(n=131), other coronaviruses (n=101)
and SARS-CoV-
2 (n=57). Our data show
that common winter pathogens circulation
changed, and influenza virus and RSV
did not produce a seasonal epidemic in
the 2020\u20132021 winter season. These data
suggest that social distancing measures
and mask wearing profoundly changed
the seasonality of winter paediatric respiratory
infections that are mainly spread
by respiratory droplets. The reasons why
rhinovirus remains the main pathogen
despite social distancing and face mask
use are still a matter of debate. Similar
data showing a decrease of common viral
respiratory infections during the winter
season have recently been reported in the
southern hemisphere.1\u20134 Our data refer
to a single institute, covering paediatric
population of the Trieste Province (about
230 000 inhabitants), limiting the generalisation
of our findings. However, our
results highlight the need for continuing
surveillance for the delayed spread of such
viruses during spring and summer
Analyses of variant human papillomavirus type-16 E5 proteins for their ability to induce mitogenesis of murine fibroblasts
BACKGROUND: Human papillomavirus type 16 (HPV-16) E5 protein co-operates with epidermal growth factor to stimulate mitogenesis of murine fibroblasts. Currently, little is known about which viral amino acids are involved in this process. Using sequence variants of HPV-16 E5 we have investigated their effects upon E5 transcription, cell-cycling and cell-growth of murine fibroblasts. RESULTS: We demonstrate that: (i) introduction of Thr(64 )into the reference E5 sequence of HPV-16 abrogates mitogenic activity: both were poorly transcribed in NIH-3T3 cells; (ii) substitution of Leu(44)Val(65 )or, Thr(37)Leu(44)Val(65 )into the HPV-16 E5 reference backbone resulted in high transcription in NIH-3T3 cells, enhanced cell-cycle progression and high cell-growth; and, (iii) inclusion of Tyr(8 )into the Leu(44)Val(65 )backbone inhibited E5 induced cell-growth and repression of p21 expression, despite high transcription levels. CONCLUSION: The effects of HPV-16 E5 variants upon mitosis help to explain why Leu(44)Val(65 )HPV-16 E5 variants are most prevalent in 'wild' pathogenic viral populations in the UK
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