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On the Entanglements of Heritage—Afterword to the Special Issue Sacred Heritage: Religions and Material Culture
No full textA sign of a productive sub-field is that it can develop ramifying links with other areas of research whilst retaining the distinctiveness that first brought it into being [...
Age structure of saplings in canopy openings of mature longleaf pine woodlands
Full text linkResearch on sapling recruitment and age structure in mature longleaf pine (Pinus palustris Mill.) woodlands is needed to inform silvicultural treatments that maintain or enhance stand structural diversity. To address this issue, we quantified sapling age structure within and across dense patches of longleaf pines that established from natural regeneration in canopy gaps of mature uneven-aged stands. We determined the age when trees emerged from the grass stage (i.e., effective age) of 475 saplings and then developed a diameter-age model to predict the ages of another 1,606 saplings. We found that the interquartile range of sapling effective ages within patches was relatively narrow, averaging 4.8 years. This provides support for the commonly held view that longleaf pine sapling patches are even-aged. We also found that there were significant differences in mean sapling effective age among patches. The means for sapling patches ranged from 20.8 to 25.9 years. Cone crop and prescribed fire records provided further support to there being multiple years in which different locations across our study area were regenerated to longleaf pine. Stands with sapling patches that have a range of mean ages could enhance stand structural diversity, which could have the co-benefit of meeting wildlife habitat objectives.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
An epidemiological framework for improving the accuracy of whole-genome sequence-based antimicrobial resistance surveillance in Salmonella
Full text linkWhole-genome sequence-based surveillance of bacteria for determinants of antimicrobial resistance promises many advantages over traditional, wet-lab approaches. However, adjustments to parameters used to identify genetic determinants from sequencing data can affect results and interpretation of the important determinants in circulation. Using a dataset of whole-genome sequences from 1633 isolates of Salmonella Heidelberg and S. Kentucky collected from surveillance of Canadian poultry production, we queried the genomic data using an in-silico AMR detection tool, StarAMR, applying a range of parameter values required for the detection pipeline to test for differences in detection accuracy. We compared the results from each iteration to phenotypic antimicrobial susceptibility results, and generated estimates of sensitivity and specificity using regression models that controlled for the effects of multiple sampling events and variables, and interactions between covariates. Results from our analyses revealed small, yet significant effects of the input parameters on the sensitivity and specificity of the AMR detection tool, and these effects differed based on the serovar and drug class in question. Findings from this study may have implications for the incorporation of whole-genome sequence-based approaches to the surveillance of antimicrobial resistance determinants in bacteria sampled from food products and animals related to food production.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Understanding the diet of an unmanaged population of coyotes (Canis latrans) in southern Texas.
Full text linkCoyotes (Canis latrans Say, 1823) have great dietary plasticity, which can variably impact population dynamics and food availability of other wildlife. Understanding coyote diet in a system with a lack of human intervention can provide insight into their natural ecological role, a perspective muddled in the context of extrinsic influences. Our study evaluated the diet of a coyote population in southern Texas where no native wildlife is managed by harvesting, trapping, or supplemental feeding, and compared our results with previous studies. We collected coyote scat from transects on the roads of the East Foundation's San Antonio Viejo Ranch every month of 2022. From morphological analysis of fecal remains, we identified 23 unique species with white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)) and invasive wild pig (Sus scrofa Linnaeus, 1758) being the most common prey items over the year, detected 38.4% and 14.4% among all prey items, respectively. The distinctly high proportion of ungulates consumed as opposed to small mammals is possibly due to high ungulate prey density as well as intraspecific niche differentiation by the unmanaged coyote population, where older, more experienced coyotes select for large mammals and younger coyotes select for small mammals. Future research exploring anthropogenic effects on predator and prey population demographics as well as predator behavior could provide more insight into how human presence may alter predator diet.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
The nuclear and mitochondrial genomes of the bellicose bumblebee (Bombus bellicosus, Hymenoptera: Apidae), a threatened pollinator in a changing South American landscape
Full text linkWe present the first genome of a Brazilian bumblebee species, the bellicose bumblebee (Bombus bellicosus). This is an endemic species in southern South America facing local extinction due to habitat loss and climate change. During the COVID-19 social distancing in Brazil, we launched a citizen science initiative via social media to locate remaining bellicose bumblebee populations, leading to the collection of a specimen for genome sequencing. Analysis of the novel genome revealed lower genetic diversity in the bellicose bumblebee compared to a widespread related species (B. pascuorum). However, the absence of extensive runs of homozygosity indicated a lack of recent inbreeding, offering a promising perspective for the conservation of this species. Furthermore, demographic history analysis indicates population expansion during past glacial periods, in contrast to Palearctic bumblebees which suffered a stark decline during glaciations. Our findings provide invaluable information for the conservation of this species and for further studies about its biology and evolution, particularly under a scenario of rapid environmental change.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
CPT-Informed Model for Rapid Penetration into Sand
Full text linkResults of rapid projectile impact experiments on sand are described, from which a phenomenological penetration model is developed. Projectiles are launched in a gravity-aligned configuration into dry and partially-saturated sand at an impact velocity of approximately 200 m/s. The velocity-time history of penetration is resolved using an optical measurement technique known as photon Doppler velocimetry (PDV). Soil resistance to penetration is found by single differentiation of the velocity-time data. Experiments suggest the existence of at least two penetration regimes separated by a stress of approximately 25 MPa. At high velocities, penetration involves intense particle crushing, whereas low velocity penetration is facilitated through particle rearrangement and localized shear failure. High velocity penetration is inefficient, and the majority of penetration occurs at lower velocities. Saturation reduces penetration resistance, particularly in denser soils. These observations are used to inform the development of the semi-analytical GeoPoncelet model, which, along with CPT tip stress, are used to directly predict the response and depth of burial or projectiles in sand with high accuracy.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
The Presence of Excitons in Short Single-Stranded DNA Revealed by Absorption and Circular Dichroism Spectroscopy
Full text linkThis paper presents a systematic absorption and circular dichroism spectroscopy study of short single strands of DNA, from 2 to 20 bases. They are composed of a sequence-specific nucleobase composition, either adenine (A), thymine (T), or AT repeats. The absorption spectra hypochromism and the circular dichroism one show butterfly-shaped spectra. Data analysis conducted on the spectra of these oligomers provides evidence for the formation of excitons and their delocalization length along the strand of DNA in relation to how many bases are involved in the excitonic coupling. In particular, the extent of this coupling is limited to adjacent nucleobases in the case of pure adenine strands but spans multiple nucleobases in the case of pure thymine strands. Predictably, AT repeats show a mixed behavior between the two
Physical and numerical investigation of deformation mechanisms of jointed pipelines due to passive face instability of EPB shield tunnelling
Full text linkThe serviceability and safety of existing pipelines may be adversely affected by differential ground movements resulting from inappropriate control of face pressure of EPB shield tunnelling. However, previous studies mainly concentrated on deformation mechanisms of continuous pipelines resulting from tunnel face active instability. In this study, sixteen three-dimensional physical model tests were conducted to explore the effects of tunnel cover-to-diameter ratio (C/D) and relative tunnel-pipeline position (H/D) on deformation mechanisms of jointed pipeline due to tunnel face passive instability. Moreover, a systematic numerical parametric study was performed to develop calculation charts for estimating joint rotation angle subjected to ground heaves. For tunnel C/D ratios of 1.0 and 1.5, the existing jointed pipeline at 0.7 D and 1.2 D ahead of tunnel face experiences the highest heave and joint ration angle, respectively. By increasing C/D ratios from 1.0 to 1.5, the maximum pipeline deformation decreases by up to 84.5%. A dimensionless group, namely relative pipe segment-soil stiffness, is proposed to distinguish relatively rigid and flexible jointed pipelines, and normalised pipe segment length and relative pipe-soil stiffness are also proposed to establish calculation charts for predicting joint rotation angles of relatively rigid and flexible jointed pipelines, respectively.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Soil fertility response to pruning, fungicide, and fertilization in lowbush blueberry
Full text linkManagement improves the growth and fruit yield of cultivated lowbush blueberries, but it remains to be seen how the pruning method, fertilizers, and fungicide applications affect soil fertility. This study investigates the impact of pruning, fungicide, and fertilization management practices on key soil parameters related to soil fertility, namely: soil organic matter (SOM) content, soil pH, nitrogen and phosphorus mineralization, nitrification, and phosphorus saturation index. A split-split-plot experiment was established, including two pruning methods (mechanical and thermal), two fungicide regimes (with or without), and three types of fertilizer applications (mineral, organic, or none). Mineral fertilizer applications significantly and strongly affected most soil fertility indicators, with increased nitrogen (+77 kg ha-1) and phosphorus (+117 kg ha-1) mineralization and SOM (+34 g kg-1), while reducing soil pH (-0.18) and nitrification (-46 kg ha-1). Thermal pruning decreased nitrification (-26 kg ha-1), soil pH (-0.12), and SOM concentration (-29 g kg-1). Fungicide applications showed no significant impact on soil fertility. While mineral fertilizer improves soil fertility, repeated application of organic fertilizer increases soil pH (+0.34), nitrification (+53 kg ha-1), phosphorus mineralization (+161 kg ha-1), and the soil phosphorus saturation index at undesirable levels (PSI>2.8 %) in lowbush blueberry production systems. The loss of SOM with thermal pruning is noteworthy and highlights the management impact and need for regular monitoring to maintain soil fertility in such fields.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Professional Development Preferences and Needs of Healthcare Providers Working with Older Adults on Exercise and Nutrition: Results of Key Informant Interviews
Full text linkMost older adults want to age in place, and evidence-based health behaviours that support aging in place include healthy diets and physical activity. Healthcare professionals need training in the science and practice of nutrition and physical activity to support their older adult clients to age in place. In this study we investigated knowledge gaps among healthcare professionals and the organizations that employ them regarding exercise and nutrition for older adults. We also aimed to identify their perceptions of effective and ineffective continuing education approaches, how they choose continuing education opportunities, and what formats they prefer when engaging in continuing education. Using key informant interviews and an interpretive description approach, we identified four themes: “Being pragmatic about professional development,” “Matching format to need,” “Negotiating the tension between the convenience of online and the effectiveness of in-person learning,” and “Focusing on practice is critical.” Participants also identified current gaps in professional development offerings and desires for additional continuing education opportunities on certain topics, such as nutrition and aging, and dealing with multimorbidity. Participants indicated that continuing education offerings should reflect common health conditions that providers encounter in practice and that there should be a balance between online and in-person offerings. Participants also indicated that continuing education should focus on changing or improving practice, to assist healthcare providers in supporting older adults aging in place in their communities.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author