21649 research outputs found
Sort by
Influence of maternal hierarchical position on offspring rank acquisition: The case of captive collared peccaries (Dicotyles tajacu)
No full textNumerous factors, such as sex, age, access to food resources, and kinship, influence the social dynamics of animals. Social position affects behavior, physiology, and reproductive outcomes in highly social mammalian species like collared peccaries (Dicotyles tajacu). Maternal position is an important determinant of social status, which is often heritable. This study aimed to assess the influence of maternal rank on the hierarchical rank of captive collared peccary offspring using social network analysis. By examining aggressive and affiliative interaction data, we generated hierarchies using David's Score and calculated social network indices (centrality, strength, and affinity) to identify individuals' roles in social stability. These analyses were performed with the SOCPROG program. Findings indicated that maternal rank did not significantly affect offspring rank. However, mothers demonstrated higher association index values compared to their offspring. We concluded that the peccary hierarchy is predominantly established through maternal associations rather than offspring interactions, suggesting that offspring rank positions may result from adults' high tolerance towards young individuals
Testing Oil-Brine and Polymer-Silica IFT with Pendant Drop (Rising Bubble) Method
Get PDFThis paper examines how polymer-coated nanoparticles (PNPs) affect interfacial tension (IFT) and their possible use in oil recovery (EOR). In particular, the paper investigates how the IFT between brine and dead oil can be lowered with the help of PNPs prepared with Arabic gum and silica nanoparticles at different temperatures and salinity. IFT was measured at pressures of 25 to 1900 psi and temperatures varying between 25˚C and 55˚C using the pendant drop technique. They demonstrate a continuous decline of IFT with temperature (the highest observed one is at 55˚C). Furthermore, elevated salinity (NaCl) resulted in reduced IFT, but it resulted more at high concentrations. High IFT further was reduced by the presence of silica nanoparticles and Arabic gum with the largest IFT reduction of about 46% potentially occurring in the brine-oil system with nanoparticles. These results indicate that PNPs may provide an attractive solution to enhancing EOR due to their ability to lower IFT, improve the efficiency of oil displacement transport in more difficult reservoirs. The research prepares the ground of additional studies regarding the use of nanotechnology in EOR processes
Build it and they will come? - A case study of a 'softer landings' approach in creating a low-carbon community
Get PDFThis paper explores an emerging low-carbon construction business model through a case study of a low-carbon community supported by a private Small to Medium Enterprise (SME) in Lincolnshire. The study highlights the developer's extended aftercare and on-site support that has a focus on engaging residents in behaviour change and low-carbon community building (termed the ‘softer landings' approach1). The research employs a mixed method approach, with multiple sources of data from in-depth interviews, a focus group discussion, and questionnaire surveys, as well as energy consumption data from Post Occupancy Evaluation (POE) on four projects over two development sites completed between 2016 and 2019. The findings suggest that extended aftercare and on-site support from the developer could cultivate a self-supporting low-carbon community that promotes peer learning and support, behaviour change, decreases energy consumption and leads to user satisfaction. The research proposes a model where the positive outcomes of the ‘softer landings approach’ could in turn drive the demand-side market for low-carbon dwellings, create further business opportunities for the developer, mitigate capital cost and resources invested in the extended aftercare, and generate business growth. Recommendations for this model to be replicated and upscaled through professional networks, and supported through policy and regulatory frameworks in the UK are presented as a constructive way forward in order to achieve the government's decarbonisation goals
Carbon Nanomaterials Applied in Cementitious Composites- A focus on mechanical properties and dispersion techniques
No full textCementitious composites are integral to civil engineering applications, yet they are subject to limitations such as nanoscale cracking. To address these challenges, this doctoral research investigates the use of Graphene Nanoplatelets (GNPs), a cost-effective nanomaterial with a large surface area that has shown promise in improving hydration, reducing porosity, and mitigating cracking in cementitious systems. The effective dispersion of GNPs, often hindered by strong internal forces, was achieved through a unique dual-method approach involving both mechanical (sonication) and chemical (Superplasticizer, SP) means.To rigorously evaluate the optimal conditions for GNP dispersion and subsequent impact on mechanical properties, an exhaustive testing regimen was implemented. GNPs were initially dispersed in water through sonication and the use of Superplasticizer (SP), with the quality of dispersion subsequently assessed via UV-Visible spectrometry. Various concentrations of GNPs and SP were then incorporated into cementitious composites. Mechanical tests were conducted to assess the composite's performance, followed by advanced characterization techniques, such as Scanning Electron Microscopy (SEM) and Dynamic Light Scattering (DLS), to examine the dispersion quality within the cementitious matrix.This research has identified an optimal GNP concentration of 0.046 wt%, rigorously verified through a suite of experimental tests to significantly enhance the mechanical properties of cementitious composites. Concurrently, an optimal SP concentration of 0.5 wt% was found to synergistically improve these properties. Uniquely, this study also delves into the often-overlooked aspect of the shelf life of GNPs in cementitious composites, providing a novel industry-relevant metric to evaluate the quality of dispersion over time. Poor dispersion quality has been shown to negate the beneficial effects of GNPs, underlining the importance of this component of the study.In summary, this doctoral research makes substantive contributions to the fields of materials science and civil engineering by offering rigorously-tested, practical solutions to age-old challenges in cementitious composites. Its findings have far-reaching implications for both academic research and industrial applications, serving as a cornerstone for future work in nano-enhanced construction materials
Carl's Story: a veteran's experience of the benefits system
Get PDFSince 2017, the University of Salford has been leading a project funded by the Forces in Mind Trust (FiMT) called Sanctions, Support & Service Leavers. The project represents the first, and only, substantive research to provide an understanding of veterans' experiences of navigating the UK social security benefits system. Prior to our study, very little was known, beyond anecdotal evidence suggesting that veterans were not always aware of, or able to access their entitlements to welfare support. Our research examined veterans' experiences across a spectrum of benefits processes and interactions, including understanding eligibility, application processes, benefits assessments, conditionality, interactions with the DWP, and intersections between benefits and Armed Forces compensation payments and pensions. Our study concluded in the summer of 2024. over the lifetime of the project, we have given voice to 108 veterans, and carried out 298 interviews. As part of our project, we commissioned professional digital illustrator, Andrea Motta, (a University of Salford graduate), to produce a graphic novel. drawing on experiences from across the sample, the research team prepared a storyboard and script, which Andrea then used to produce the images you see here. In its finished form, the graphic novel is the result of a dialogue between the research team and Andrea, who guided us on how the story might work effectively as a visual narrative. This graphic novel tells the story of a veteran of the British Armed Forces called Carl after he leaves Service and navigates his way through civilian life. It explores his experiences of transition and employment, but the main focus is his contact with different parts of the UK benefits system. Although 'Carl' is not a real person, the issues raised in this graphic novel are rooted in the real life experiences of veterans across our research. The aim of Carl's story is not to re-inforce negative stereotypes that are sometimes associated with past military experience around PTSD, substance abuse or homelessness, for example. But neither should we shy away from the challenges that some service leavers can experience, and how this can bring them into contact with the benefits system. Our sample, therefore, reflected those who had faced (often multiple) challenges in civilian life, before and after Service. In this graphic novel, we position Carl as someone who left service somewhere in the period 2000-10, so his experiences of transition support are very different from those who left in the 1980s - or, indeed, someone who left in the last five years. His story is not, therefore, meant to be a picture of contemporary resettlement and transition support, although some of the same challenges may still occur. Most of the veterans we spoke to found employment quite quickly after leaving the Armed Forces and did not come into contact with the benefits system until many years later, often at times of crisis in their life. Carl's story reflects this. As most of our interviewees were male, we chose to make the central character a man, but we are aware the specific experiences of female veterans also need recognition
Quantifying the benefits of incorporating biochar in green roof substrates: field study on the highrise rooftop in temperate climate setting
Get PDFBiochar is a promising material with a wide range of applications. One area of application is as an additive in substrates for green roofs. Green roofs are a way of mitigating climate change, with biochar offering an opportunity to further enhance this benefit and upscale practice. In this field study, the effect of a 5-vol.% addition of wood-based biochar to a green roof substrate is evaluated with respect to a water balance (reduced runoff, increased evapotranspiration, increased plant available water) and hydrophysical properties. Substrate, with and without biochar amendment, was used in different green roof sections. Laboratory hydrophysical analysis, in-situ Volumetric Water Content and meteorological measurements, alongside vegetation monitoring, enabled the development of a 1D Hydrus water balance model and revealed differences between both of the surveyed green roofs. The study demonstrated that the addition of biochar to the substrate improved its hydrophysical properties, leading to increased water retention (7.7% increase in maximum water capacity) and enhanced vegetation growth The biochar amendment resulted in the minor changes in grain size distribution (increase in the 0.01 to 0.1 mm fraction) and increased substrate moisture, which is related to an increase in the plant-available water content (14.2%). This was observable in the retention curves and resulted in an increased moisture availability for plants, leading to an increase in vegetation cover in areas with biochar. The numerical analysis using Hydrus-1D soil hydraulic model showed that the inclusion of biochar in the substrate resulted in a 23.5% increase in evapotranspiration and a 54.7% decrease in runoff. These findings suggest that the addition of biochar to the green roof substrate could enhance the system's capacity to retain water, reduce runoff and bulk density, and increase the amount of water available for plant growth. The study provides evidence for the potential of wood-based biochar as a sustainable and effective addition to green roof substrates, contributing to the development of more resilient and sustainable urban environments. Graphical Abstract
An efficientnet-based model for classification of oil palm, coconut and banana trees in drone images
Get PDFOil palm tree detection and classification from coconut and banana trees is vital for increasing the production of oil palm businesses globally, particularly in Malaysia. Since oil palm, coconut, and banana trees share common characteristics such as tree shape and structure, classification is challenging. Further, this work considers images captured by drones, which adds complexity to the classification problem. Unlike most existing methods that primarily detect oil palm trees, the proposed work aims to detect and classify multiple tree types. Inspired by the success of the Segment Anything Model (SAM), a generalized model for object segmentation, we adapted SAM for detecting and localizing oil palm, coconut, and banana trees in drone images. Similarly, motivated by the efficiency and effective feature extraction of EfficientNetB3, we integrated it for the classification task. The proposed model combines SAM for detection and EfficientNetB3 for classification in an end-to-end architecture. To evaluate its performance, we conducted experiments on a dataset collected from a Malaysian drone services company, featuring frames captured across diverse locations. Results demonstrate that the proposed method significantly outperforms state-of-the-art approaches. For detection, the proposed SAM achieves F1-scores of 97 %, 89 %, and 91 % for oil palm, coconut, and banana trees, respectively. For classification, the proposed model achieves F1 scores of 92 %, 88 %, and 91 % for oil palm, coconut, and banana trees, respectively. The results show that the proposed method is superior to the existing methods
Citizen Scientists: Motivation to Participate in Environmental DNA (eDNA) Surveys: A Case Study on Monitoring Mammals in the UK
Get PDFCitizen scientists have become integral participants in biodiversity monitoring, and the demand for effective surveying efforts has sparked interest in utilizing environmental DNA (eDNA) for species monitoring, drawing volunteers into survey planning and sample collection. However, there remains a gap in understanding the motivations behind volunteer engagement in surveys that don’t involve direct observations of species, including the need to validate collected data and recognize volunteer contributions to ensure their satisfaction. To address this gap, we used questionnaires to assess volunteer science capital, motivation to participate, and their experiences during eDNA sampling. We trained ten conservation volunteers, all of whom were members of the Essex Wildlife Trust, to collect eDNA samples from two rivers and a beaver enclosure to detect terrestrial and semi-aquatic mammals. Citizen scientists were highly motivated and demonstrated high science capital, enabling them to develop innovative eDNA sampling methods and take enjoyment in contributing to meaningful scientific knowledge and helping their local wildlife. Additionally, citizen scientists detected more species compared with eDNA researchers, underscoring the value of local knowledge, and the longer sampling periods associated with typical citizen scientist projects. This case study highlights the benefits of involving citizen scientists in eDNA surveys, as sharing results led to meaningful discussions about the species detected and further enriched knowledge exchange. The case study’s limitations include small sample size and limited participant diversity in terms of age, gender, and ethnicity. However, the findings can inform future research with larger and more diverse participants
Characterization of a trypanosome from large yellow croaker (Larimichthys crocea), cage-cultured in seawater, in China
Get PDFA significant outbreak of trypanosomosis occurred in farmed large yellow croaker (Larimichthys crocea) in Southeast China resulting in daily mortality rates, over 70 days, of up to 1 % with cumulative losses nearing 60 %. Despite the severity of the outbreak, details of the specific trypanosomes infecting large yellow croaker remain unclear. In this study, samples of fish were collected from the fish farmer during the outbreak. A high prevalence of trypanosomes, confirmed by microscopy and PCR analysis, was associated with pathology. Sequence identification and phylogenetic analysis indicated that the isolated trypanosome had 99.27 % sequence identity with Trypanosoma carassii MARV, a typical freshwater fish trypanosome, and clustered within the T. carassii complex C group. Morphological characterization, using Giemsa staining, further supported the similarity between the trypanosomes infecting large yellow croaker and the T. carassii complex C group. Additionally, a broader host range was established as it also infected Nile tilapia (Oreochromis niloticus), koi (Cyprinus carpio) and largemouth bass (Micropterus salmoides), leading to its designation as a subspecies within the T. carassii complex, named T. carassii spectrum. This represents the first documented instance of T. carassii, a typical freshwater fish trypanosome, infecting a marine fish whilst highlighting its severe pathogenicity and the urgent need for effective control measures. Furthermore, in vitro cultivation was successfully established, providing a foundation for future research on prevention and management strategies
Data sources:
Access Repository Dashboard
Do you manage University of Salford Institutional Repository? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!