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The effect of wetting history, botanical composition and depth on the specific yield of two common types of bog peat
Get PDFSpecific yield affects how much the water table rises and falls in response to rainfall, to evaporation and to seepage gains and losses. It also affects the aeration of the soil above the water table. Although widely measured in peat soils, the effect of wetting history on its value has not been investigated. Specific yield has been estimated in many studies by cutting peat cores into layers, and measuring how much water drains from the individual layers after they have been wetted. Specific yield, however, is a phenomenon of the soil profile and not subsections, so this method may not provide a reliable estimate of its value. Few studies have reported on the effect of botanical composition on specific yield, or at least have not controlled for the effect by keeping other peat properties like degree of humification constant. We addressed these questions by measuring specific yield in intact cores of peat in a series of laboratory experiments. Two common but contrasting types of Sphagnum peat were investigated that had similar degrees of humification: Sphagnum medium peat and Sphagnum pulchrum peat. We found that specific yield was highly variable, ranging between 0.16 and 0.62. Specific yield was not affected by wetting history, but was significantly different between the peat types, being on average 0.21 higher in the S. pulchrum cores. Specific yield did not vary with depth in the S. medium cores but declined linearly with depth at a rate of 0.018 per cm in the Sphagnum pulchrum cores. Finally, we found that drainage from the peat profile above the zone through which the water table falls is an important component of specific yield, contributing more than 66%–91% of its value in the S. pulchrum peat. Our results show that wetting history probably does not need to be accounted for when estimating specific yield, although further work on this potential effect is recommended. Our work highlights the importance of measuring specific yield using intact cores (field methods may also be appropriate) and suggests that many previous peatland studies may have underestimated its value
Creation and validation of the Online Self-Disclosure via Educational Platforms Scale
Get PDFGlobally, higher education (HE) institutions now implement some element of hybrid learning, heightened since the COVID-19 pandemic and temporary shift to online learning. To communicate, online self-disclosure (revealing information about the self) is required. The majority of HE students are aged between 18-24 years, which is considered the developmentally sensitive period of ‘emerging adulthood’. Having only ever known a digitally-connected world, emerging adults self-disclose differently to other generations when communicating via an online environment. Whilst communicating online with HE staff, students may self-disclose in a way that misaligns with the expectations of staff; this may result in miscommunication or over-disclosure (revealing inappropriate information to a misjudged audience). Over-disclosing via online educational platforms (e.g., Moodle, MS Teams, and e-mail) may result in negative feedback from staff and this may impact student experience, engagement and attainment. Problematically, no standardized measure exists that captures student self-disclosure via online educational platforms and so research on this topic is currently limited and theoretically unstable. Via a three-phase study, comprising four studies and 283 participants, we have created and conducted an initial evaluation of the online self-disclosure via educational platforms (OSDEP) scale. The OSDEP scale is the first psychometric tool to specifically measure HE students’ online self-disclosure behaviors specifically within an online educational context. The OSDEP scale can be used for future educational and pedagogical research to further understand HE students’ online self-disclosure behaviors and to what extent these may be associated with topics such as mental health, engagement, attainment, and student experience
Thirty Years of Progress in Our Understanding of the Nature and Influence of Fire in Carboniferous Ecosystems
Get PDFUntil the late 20th century, the idea of identifying wildfires in deep time was not generally accepted. One of the basic problems was the fact that charcoal-like wood fragments, so often found in sedimentary rocks and in coals, were termed fusain and, in addition, many researchers could not envision wildfires in peat-forming systems. The advent of Scanning Electron Microscopy and studies on modern charcoals and fossil fusains demonstrated beyond doubt that wildfire residues may be recognized in rocks dating back to at least 350 million years. Increasing numbers of studies on modern and fossil charcoal assemblages from the 1970s through the 1990s established the potential importance of wildfires in the fossil record, using Carboniferous examples in particular. Since the 1990s, extensive progress has been made in understanding modern wildfires and their byproducts. New techniques to study ancient charcoals have allowed considerable progress to be made to integrate modern and ancient fire studies, both before and after the evolution of mankind. Four important developments have made a reassessment of Carboniferous wildfires necessary: the recognition of the role of atmospheric oxygen in controlling the occurrence of wildfire; the development of new microscopical techniques allowing more detailed anatomical data to be obtained from charcoal; the integration of molecular studies with the evolution of fire traits; and new developments in or understanding of post-fire erosion/deposition systems
Researching race, accounting, and accountability:past, present, and future
Get PDFAbstractPurpose: This paper introduces the special issue on Race and accounting and accountability. In so doing, it explores racism in its historical and contemporary forms and, the role of accounting and accountability in enabling racism and racial discrimination, and also efforts of redress and resistance. Design/methodology/approach: We reflect on several critical themes to demonstrate the pervasive and insidious nature of racism and, review the literature on race and racism in accounting, focusing on studies that followed the seminal work by Annisette and Prasad (2017) who called for more research. We also review the six papers included in this special issue. Findings: While many overt systems of racial domination experienced throughout history have subsided, racism is engrained in our everyday lives and in broader societal structures in more covert and nuanced forms. Yet, in accounting, as Annisette and Prasad noted, focus has continued to be on the historical. This special issue shifts this imbalance - five of the six papers focus on contemporary racism. Moreover, it demonstrates that although accounting technologies can and do facilitate racism and racist practices, accountability and counter accounts offer avenues for calling out and disrupting the powers and privileges that underlie racial discrimination and, resistance by un-silencing minority groups subjected to discrimination and injustice. Originality: This introduction and the papers in the special issue offer rich empirical and theoretical contributions to accounting and accountability research on race and racial discrimination. We hope they inspire future race research to nurture progress towards a true post-racial society. Keywords: accounting; accountability; contemporary discrimination; exploitation; race; racism. <br/
Foraging distance distributions reveal how honeybee waggle dance recruitment varies with landscape
Get PDFHoneybee (Apis mellifera) colonies use a unique collective foraging system, the waggle dance, to communicate and process the location of resources. Here, we present a means to quantify the effect of recruitment on colony forager allocation across the landscape by simply observing the waggle dance on the dancefloor. We show first, through a theoretical model, that recruitment leaves a characteristic imprint on the distance distribution of foraging sites that a colony visits, which varies according to the proportion of trips driven by individual search. When we fit this model to the real-world empirical distance distribution of forage sites visited by 20 honeybee colonies in urban and rural landscapes across South East England, obtained via dance decoding, we find considerable variation in the use of dancing in colony foraging, particularly in agri-rural landscapes. In our dataset, reliance on dancing increases as arable land gives way to built-up areas, suggesting that dancing may have the greatest impact on colony foraging in the complex and heterogeneous landscapes of forage-rich urban areas. Our model provides a tool to assess the relevance of this extraordinary behaviour across modern anthropogenic landscape type
Caregivers' Perceptions of COVID-19 Educational Disruptions on Children With Developmental Language Disorder and Typically Developing Peers
Get PDFHyperbolic Translation-Based Sequential Recommendation
Get PDFThe goal of sequential recommendation algorithms is to predict personalized sequential behaviors of users (i.e., next-item recommendation). Learning representations of entities (i.e., users and items) from sparse interaction behaviors and capturing the relationships between entities are the main challenges for sequential recommendation. However, most sequential recommendation algorithms model relationships among entities in Euclidean space, where it is difficult to capture hierarchical relationships among entities. Moreover, most of them utilize independent components to model the user preferences and the sequential behaviors, ignoring the correlation between them. To simultaneously capture the hierarchical structure relationships and model the user preferences and the sequential behaviors in a unified framework, we propose a general hyperbolic translation-based sequential recommendation framework, namely HTSR. Specifically, we first measure the distance between entities in hyperbolic space. Then, we utilize personalized hyperbolic translation operations to model the third-order relationships among a user, his/her latest visited item, and the next item to consume. In addition, we instantiate two hyperbolic translation-based sequential recommendation models, namely Poincaré translation-based sequential recommendation (PoTSR) and Lorentzian translation-based sequential recommendation (LoTSR). PoTSR and LoTSR utilize the Poincaré distance and Lorentzian distance to measure similarities between entities, respectively. Moreover, we utilize the tangent space optimization method to determine optimal model parameters. Experimental results on five real-world datasets show that our proposed hyperbolic translation-based sequential recommendation methods outperform the state-of-the-art sequential recommendation algorithms
Scalable Event-by-Event Processing of Neuromorphic Sensory Signals With Deep State-Space Models
Get PDFNeural correlates of pain acceptance and the role of the cerebellum:Functional connectivity and anatomical differences in individuals with headaches versus matched controls
Get PDFBackground: Despite functional connectivity network dysfunction among indi-viduals with headaches, no studies have examined functional connectivity neuralcorrelates and anatomical differences in coping with headaches.Methods: This study investigated inter-individual variability in whole-brainfunctional connectivity and anatomical differences among 37 individuals withprimary headaches and 24 age- and gender-matched controls, and neural cor-relates of psychological flexibility (PF) that was previously found to contributeto headache adjustment. Participants (84% women; M headache severity = 4/10;M age = 43 years) underwent functional magnetic resonance imaging scans andcompleted questionnaires to examine global and subnetwork brain areas, andtheir relations with PF components, controlling for age, gender, education, andhead- motion.Results: Seed and voxel-based contrast analyses between groups showed atypicalfunctional connectivity of regions involved in pain matrix and core resting-statenetworks. Pain acceptance was the sole PF component that correlated with thecerebellum (x, y, z: 28, −72, −34, p-false discovery rate <0.001), where individualswith headaches showed higher grey matter density compared to controls.Conclusions: The cerebellum, recently implicated in modulating emotional andcognitive processes, was indicated to process information resembling what indi-viduals do when practicing pain acceptance. Our findings establish for the firsttime this connection of the cerebellum and its role in pain acceptance. We pro-pose that pain acceptance might be a behavioural biomarker target that couldmodulate problematic headache perceptions and brain networks abnormalities
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