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SAT-Web: a web-based educational SAT visualisation tool
Get PDFProvision of tools for explaining SAT solvers and visualising SAT instances helps to facilitate easier entry to
the field for newcomers, yet this remains an under-explored area. In this tool paper we present SAT-Web, a
web-based educational tool for explaining SAT solving, and the first tool of its kind which can be used entirely
from a web-browser. Our tool provides visualisations with search trees and variable interaction graphs, and
includes a DPLL solver with tracing. We explain the design, techniques and implementation details behind the
tool. We also review approaches and tools for instance visualisation and existing pedagogical tools designed to
explain solvers. Finally, we discuss potential future improvements and opportunities for SAT visualisation and
pedagogical tools
Differing impacts of livestock farming and ranching on aquatic insect biodiversity: a global meta-analysis
No full textRecent studies examining global insect biodiversity trends have shown declines for many terrestrial species but increases in some aquatic species, albeit with limited spatial coverage. However, the impact of a wide range of threats on insect biodiversity remains uncertain at a global scale. Livestock farming and ranching constitute approximately 30% of global land use and represent a major and growing threat to biodiversity. Although we know livestock farming and ranching affect aquatic macroinvertebrates via degradation of water quality and habitat, there are no global syntheses of the impacts of livestock on the biodiversity of aquatic insects. Here, we investigate the impact of livestock farming and ranching on the abundance and richness of five major aquatic insect orders: Ephemeroptera (mayflies), Plecoptera (stoneflies), Trichoptera (caddisflies), Megaloptera (dobsonflies and alderflies), and Odonata (dragonflies and damselflies). Our meta-analysis shows that livestock farming significantly reduces species richness of Ephemeroptera, Trichoptera, and Plecoptera compared to areas with no livestock present. In contrast, we found no overall impact of livestock farming on the abundance of aquatic insects or individual orders, even after accounting for moderators such as livestock type, riparian vegetation presence, and stocking density. The apparent stability in insect abundance, combined with declines in richness, suggests there may be shifts in community composition that cannot be captured with a broad-scale analysis. Further research is needed at finer taxonomic resolution, coupled with increased reporting of quantitative stocking density and livestock water access, to better understand the apparently heterogeneous effects of livestock on aquatic insects and predict the impacts of further spread and intensification of livestock farming
Private equity diversity and talent: do they matter for acquisitive growth?
No full textBuilding on the strategic entrepreneurship perspective and upper echelon theory, we examine the importance of private equity (PE) functional human capital and socio-demographic diversity for the success of the acquisitive growth strategy. Our focus is on the buyout lead partner team (LPT) rather than on human capital at the collective PE firm (or fund) level. The results of our panel data survival models suggest that gender and age diversity, as well as the financial background, significantly accelerate both first and subsequent add-on acquisitions. The results are robust to alternative proxies, model specifications and endogeneity checks
Beyond breakdown: enacting infrastructural life with Augustin Daly’s Under the Gaslight
Get PDFAlternation between mundane invisibility and spectacular foregrounding is a critical touchstone of infrastructural aesthetics. Moments of infrastructure failure, which mediate between these states, therefore attract disproportionate attention despite causing scholars to focus on things that no longer function as infrastructure. This article seeks to escape this impasse through analysing cultural artefacts for evidence of processes which are inconspicuous but nevertheless constitute the happenings of infrastructure. Through four short essays which engage with Under the Gaslight (1867), a sensation drama which interweaves melodramatic narratives with infrastructural spaces and temporalities, we introduce three techniques for navigating the representational slipperiness of infrastructural processes and relations. We suggest that following fictional characters’ engagements with infrastructures can disclose the experiential textures of mundane infrastructural functioning, that engaging with fiction across historical distance can defamiliarise formerly mundane infrastructural processes and render them spectacular, and that examining the infrastructural promises embedded in melodrama can foreground infrastructure’s temporalities
Nutritional status reshapes gut microbiota composition in adolescent Afghan refugees in Peshawar, Pakistan
Get PDFAlthough the human gut microbiome, and its role in health and disease, have been extensively studied in different populations, a comprehensive assessment of gut microbiome composition has not been performed in vulnerable refugee populations. In this study, we hypothesized that overall nutritional status, as indicated by serum micronutrients concentrations, is an important driver of variations in gut microbiome composition. Therefore, gut-microbiome diversity and associated demographic, health and nutritional factors were assessed in adolescent Afghan refugees (n=206). Blood
and faecal samples were collected and analysed for nutrition status markers and 16S rRNA gene amplicon-based community profiling, respectively. Bioinformatics and statistical analysis were performed using SPSS, QIIME and R. Overall, 56 distinct phyla, 117 families and 252 genera were identified in the faecal samples. Bacterial diversity (alpha and beta diversity) and the Firmicutes:Bacteroidetes (F/B) ratio were
significantly higher in the 15–19 year old age group (cf. the 10-14 age group) but were lower in the underweight and vitamin D deficient groups. Furthermore, LEfSe analysis
identified significant differences in the relative abundance of bacterial genera based on age, BMI and micronutrient (vitamins and minerals) status. These results were further
scrutinised by correlation analysis which confirmed that age, BMI and micronutrient status show significant correlations with F/B ratio and the relative abundance of
specific bacterial taxa. Collectively, our study provides the first indication of how the gut-microbiota profile of adolescent Afghan refugees is associated with a range of
nutrition-status factors. These findings can thus provide a basis for translational microbiota research aimed at improving the health of such understudied and vulnerable populations
Dimensions of corvid consciousness
Get PDFCorvids have long been a target of public fascination and of scientific attention, particularly in the study of animal minds. Using Birch et al.’s (2020) 5-dimensional framework for animal consciousness we ask what it is like to be a corvid and propose a speculative but empirically informed answer. We go on to suggest future directions for research on corvid consciousness and how it can inform ethical treatment and animal welfare legislation
Improved time constant of a newly released air temperature sensor and its implications
Get PDFThe World Meteorological Organization (WMO), National Oceanic and Atmospheric Administration, and other organizations provide guidance on expected response time for sensors used to measure air temperatures intended for meteorological applications. Quantified as the sensor time constant (the time it takes for a sensor to reflect some percentage of a step change), recommendations differ somewhat depending on the organization. For instance, the WMO specifies the 63% time constant should be ≤20 s, although, crucially, the organization does not state the air flow velocity at which this time constant should be achieved. Recent independent tests at two laboratory facilities (initially the University of Reading, United Kingdom, and subsequently at Campbell Scientific, Logan, Utah, United States) were undertaken to determine time constants of a range of commercially available platinum resistance thermometer sensors. Results showed that many sensors fell far short of the WMO specification at airflow rates typical of naturally ventilated thermometer screens or radiation shields (1 m·s−1 or lower). In contrast, a recently released platinum resistance thermometer sensor from Campbell Scientific was shown to meet both specifications, even at airflow rates within a laboratory wind tunnel as low as 0.2 m·s−1, which is more typical of naturally ventilated thermometer screens or radiation shields. Across multiple sensors and repeated test runs, the new sensor's 63% response time averaged 10.7 s (standard deviation 0.5 s) at an airflow of 1 m·s−1 and 17.1 s (standard deviation 0.9 s) at 0.2 m·s−1. To our knowledge, this is the first commercially available sensor to attain this WMO specification. However, using or switching to faster-response sensors has important implications for long-term data records, the measurement of extreme temperatures (specifically daily maximum and minimum data), and intersite comparisons. This is compounded by seemingly conflicting recommendations from the WMO regarding sensor time constant versus data processing methods
JWST/NIRSpec detection of complex structures in Saturn's sub‐auroral ionosphere and stratosphere
Get PDFPast observations of Saturn's sub‐auroral ionosphere have provided no detailed longitudinal
information, and variations in underlying stratospheric emission from methane fluorescence have never been
resolved spatially. Here, we present the first near‐infrared observations of Saturn using JWST's NIRSpec‐IFU,
revealing the 2.8–5.2 micron wavelength region in unprecedented detail. We observe the rotating auroral
enhancement associated with planetary‐period currents, the phase of which is re‐discovered for the first time
since Cassini. We discover a series of ionospheric dark beads located between 55 and 65°N, that appear to be
formed by local thermospheric dynamics. In the fluorescing methane, we reveal strange dark arms extending
equatorward from a dark polar cap at 60°N; four arms from a six‐pointed star, each extend below 45°N with the
final two arms missing. Neither set of features has any known analog at other planets
Dynamic talent management and retention strategies at growth-oriented entrepreneurial firms
No full textThis research aims to shed light on the scattered and incomplete story on how
entrepreneurially relevant contingencies influence the decision-making around talent, its
retention, and strategies for its management during periods of growth. A multiple case study
methodology and an abductive strategy has been used to study the phenomena from the
perspective of three distinct organisational actors at five firms selected based on a pre-set
array of growth-indicating characteristics. Most extant research on talent and its management
is in the context of larger organisations, and the study uncovers notable implications for how
talent is identified, retained and thus managed in this unique context of growth-stage
entrepreneurial firms. This study also responds to calls for future research directions in the
extant talent management literature to move the discourse from debates on conceptualisation
and boundaries to actual implementation. The study adds to the limited understanding in
extant literature of the distinct characteristics of entrepreneurial firms, such as prevalence of
informality and significant influence of founders, to uncover the nuances of talent
management design and implementation challenges. The study finds the preferred position
for talent in these organisations to be exclusive; however, the trajectory that their talent
management programs take dynamically evolve from ‘informally-exclusive’ to ‘formally-exclusive’, forming the two ends of a continuum. Thus, the identification, retention and
management of talent is ‘espoused in an exclusive’ manner but ‘enacted in an inclusive’
style. This finding contrasts with the inclusive versus exclusive debate that dominates the
extant literature, and points to a potential misalignment in expectations of the organisational
decision-makers and the talented employees. Another major finding is the
interconnectedness of talent identification and retention in the broader context of talent
management, pointing to a dynamic relationship that involves ongoing interactions and
feedback loops between these constructs. This led to a comprehensive framework for
dynamically evolving effective talent management practices where talent identification and
talent retention evolve in response to the shifting needs of firms at different growth stages. By
uncovering the reactions and expectations of founder/s and talented employees, a
contribution to practice and theory is a framework for firms to devise bespoke retention
strategies using distinct organisational levers. This analysis also contributed to
conceptualisation of weak and strong turnover signals, which when combined with retention
strategies, led to the development of an evidence-based framework for enhancing retention.
Further, by analysing not just the broader context of growth-oriented firms, but the sub-context of each individual firm, a roadmap for anticipating transitions in talent management
trajectories has been proposed that not only delineates the growth stages, but also identifies
the growth triggers indicating transition. The framework identifies factors causing gaps in
perspectives between founders and talented employees during firm growth, and recommends
actionable strategies to reduce these gaps, thereby improving the effectiveness of talent
retention efforts. It is hoped that this study prompts further research that advances
understanding of the interplay of actors, contexts, and growth stages in furthering talent
management agendas in practice
Techno‐economic and lifecycle analysis of green colloidal silver: moving toward scale‐up
Get PDFSilver particles (AgPs) are increasingly used across a range of industries, including personal care, household, and food packaging, but conventional synthesis methods involve high production costs and negative environmental impacts. Green synthesis using plant extracts offers a sustainable alternative, though limited comparative data on economic and environmental performance exist. This study evaluates three green methods—BX3 (a patented extract), lemon juice (LJ), and green tea (GT)—against a conventional method using sodium borohydride (NaBH₄). Equal‐volume reactions are analyzed via ICP‐MS, UV–vis spectroscopy, and dynamic light scattering. Techno‐economic analysis and life cycle assessment (LCA) assessed costs and environmental impact. BX3 emerged as the most cost‐effective and environmentally friendly option, producing AgPs at 195,000/kg, 15x more expensive than the BX3 method, and a global warming potential of 74,000 kg CO₂‐Eq/kg. GT, while a green method, has the highest cost $690,000/kg, the lowest yield (1.13%), and the worst environmental impact, including a human toxicity value of 92,000 kg 1,4‐DCB‐Eq/kg‐even surpassing the toxic NaBH₄ process. These findings highlight BX3's promise for scalable, low‐impact AgP production and broader industrial use