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Spatial distribution, risk index, and correlation of heavy metals in the Chuhe River (Yangtze Tributary): preliminary research analysis of surface water and sediment contamination
This comprehensive study aimed to evaluate the water quality and sediment contamination in the Chuhe River in Nanjing. The spatial assessment of 10 samples collected in September highlighted that, in surface water, Copper (Cu) > Nickel (Ni) > Zinc (Zn) > Chromium (Cr) > Lead (Pb) > Arsenic (As) > Cadmium (Cd) > Mercury (Hg), whereas in sediments, Zn > Cr > Cu > Pb > Ni > As > Cd > Hg. The coefficient of variation (CV) for Ni and Zn in surface water was >15, whereas As, Cu, Pb, and Ni had a CV that was higher than 15 in sediments, indicating variability in contamination sources. The Pollution Load Index values ranged between 2.16 and 3.05, reflecting varying contamination levels across samples. The Geoaccumulation Index data also showed moderate-to-considerable contamination, especially for elements such as Cd and Cu. Correlation analyses in water and sediments unearthed significant relationships, with notable links between Cu and Pb in the water and strong correlations between As and Cu and between Cr and Ni in sediments. In sediments, Total Nitrogen and Phosphorus were significantly correlated with As, Cu, Pb, and Ni. The Potential Ecological Response Index for sediments indicated that they are at medium to high risk (307.47 ± 33.17) and could be potentially detrimental to aquatic life in the tributary. The tributary, influenced by agricultural runoff, residential areas, and other anthropogenic activities, showed that despite Nemerow pollution index values for water samples being below 1, sediment analysis indicated areas of concern. Principal Component Analysis (PCA) was conducted to identify the potential sources of heavy metal contamination. In surface water, shared negative loadings on PC 1 (60.11%) indicated a unified influence, likely from agricultural runoff, while PC 2 (14.26%) revealed additional complexities. Sediments exhibited a unique signature on PC 1 (67.05%), associated with cumulative agricultural impacts, with PC 2 (18.08%) providing insights into nuanced factors, such as sediment composition and dynamic interactions. These findings offer a complete insight into the Chuhe River tributary’s condition, underlining the urgency for ongoing monitoring and potential remediation measures
Size dependent effectiveness of engineering and administrative control strategies for both short- and long-range airborne transmission control
Ventilation is recognized as an effective mitigation strategy for long-range airborne transmission. However, a recent study by Li et al. revealed its potential impact on short-range airborne transmission as well. Our study extends their work by developing size-dependent transmission models for both short- and long-range airborne transmission and evaluates the impact of various control strategies, including ventilation. By adopting a recently determined mode-dependent viral load, we first analyzed the role of different sizes of droplets in airborne transmission. In contrast to models with a constant viral load where large droplets contain more viruses, our findings demonstrated that droplets ranging from ∼2–4 μm are more critical for short-range airborne transmission. Meanwhile, droplets in the ∼1–2 μm range play a significant role in long-range airborne transmission. Furthermore, our study indicates that implementing a size-dependent filtration/mask strategy considerably affects the rate of change (ROC) of virus concentration in relation to both distancing and ventilation. This underscores the importance of factoring in droplet size during risk assessment. Engineering controls, like ventilation and filtration, as well as administrative controls, such as distancing and masks, have different effectiveness in reducing virus concentration. Our findings indicate that high-efficiency masks can drastically reduce virus concentrations, potentially diminishing the impacts of other strategies. Given the size-dependent efficiency of filtration, ventilation has a more important role in reducing virus concentration than filtration, especially for long-range airborne transmission. For short-range airborne transmission, maintaining distance is far more effective than ventilation, and its effectiveness is largely unaffected by ventilation. However, the influence of ventilation on virus concentration and its variation with the distance mainly depend on the specific transmission model utilized. In sum, this research delineates the differential roles of droplet sizes and control strategies in both short- and long-range airborne transmission, offering valuable insights for future size-dependent airborne transmission control measures
Global change in agricultural flash drought over the 21st century
Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop cultivation. Increases in the frequency of these rare events in a future warmer climate would have significant societal impact. This study uses an ensemble of 10 Coupled Model Intercomparison Project (CMIP) models to investigate the projected change in agricultural flash drought during the 21st century. Comparison across geographical regions and climatic zones indicates that individual events are preceded by anomalously low relative humidity and precipitation, with long-term trends governed by changes in temperature, relative humidity, and soil moisture. As a result of these processes, the frequency of both upper-level and root-zone flash drought is projected to more than double in the mid-and-high latitudes over the 21st century, with hot spots developing in the temperate regions of Europe, and humid regions of South America, Europe, and southern Africa
Scoring goals: The impact of English Premier League football teams on local university admissions
Anecdotal evidence suggests that co-location with an English Premier League (EPL) football team can boost university recruitment. But when a town or city loses its EPL team, it also loses some of the world’s attention. We test whether the EPL limelight does in fact affect university recruitment in England and Wales. We exploit the sharp annual cutoff between survival and relegation from the EPL, comparing the admissions outcomes of universities that have clear name association either side of that discontinuity. On average, losing association with an EPL team, for just one year after its relegation, significantly reduces a university’s undergraduate year-to-year admissions growth by 4-8 percent. These findings suggest not only that the EPL generates local externalities but also that university executives should support their local teams
Mapping taste and flavour traits to genetic markers in lettuce Lactuca sativa
Lettuce is the most highly consumed raw leafy vegetable crop eaten worldwide, making it nutritionally important in spite of its comparatively low nutrient density in relation to other vegetables. However, the perception of bitterness caused by high levels of sesquiterpenoid lactones and comparatively low levels of sweet tasting sugars limits palatability. To assess variation in nutritional and taste-related metabolites we assessed 104 members of a Lactuca sativa cv. Salinas x L. serriola (accession UC96US23) mapping population. Plants were grown in three distinct environments, and untargeted NMR and HPLC were used as a rapid chemotyping method, from which 63 unique Quantitative Trait Loci (QTL) were identified. We were able to identify putative regulatory candidate genes underlying the QTL for fructose on linkage group 9, which accounted for up to 36 % of our population
variation, and which was stable across all three growing environments; and for 15-p-hydroxyyphenylacetyllactucin-8-sulfate on linkage group 5 which has previously been identified for its low bitterness, while retaining anti-herbivory field effects. We also identified a candidate gene for flavonoid 3′,5′- hydroxylase underlying a
polyphenol QTL on linkage group 5, and two further candidate genes in sugar biosynthesis on linkage groups 2 and 5. Collectively these candidate genes and their associated markers can inform a route for plant breeders to improve the palatability and nutritional value of lettuce in their breeding programmes
Investigating the effects of Podoplanin signalling on VEGF-C-mediated signalling in human dermal lymphatic endothelial cells
Background
Interaction of podoplanin-lymphatic endothelial cells (LECs) with platelet-CLEC-2 plays
several physiological roles including lymphatic vessel development and solid organ
development. It is also involved in many pathological conditions including atherosclerosis,
deep venous thrombosis, and metastasis. Podoplanin ligation by platelets or antibody-mediated crosslinking has been demonstrated to modulate VEGF-C-mediated LEC
functions, however, the signalling mechanisms involved in this process are poorly
understood.
Aim
Investigate LEC podoplanin signalling mechanisms and to determine how podoplanin
ligation modulates VEGF-C-mediated LEC behaviour and signalling.
Methods
Trans-well migration and proliferation assays investigated the effect of platelets on LEC
behaviour. The effect of podoplanin crosslinking by recombinant CLEC-2 or antibodies, in
the presence and absence of VEGF-C, on ERM, ERK1/2 and AKT phosphorylation was
assessed using Western blotting. Colocalisation of podoplanin with other membrane
partner proteins was imaged using Total Internal Reflection Fluorescence microscopy
(TIRF) combined with Direct Stochastic optical reconstruction microscopy (dSTORM).
Results
Co-culture of platelets with LECs induces clustering of podoplanin and inhibits VEGF-C-mediated cell migration. Mimicking the crosslinking of podoplanin using recombinant
CLEC-2 or antibodies inhibits LEC migration and proliferation. Crosslinking of
podoplanin does not change basal ERM phosphorylation or alter VEGF-C-mediated
ERK1/2 or AKT phosphorylation. Podoplanin resides in CD9-containing domains which is
altered following VEGF-C stimulation. Super-resolution dSTORM microscopy
demonstrates that the association between podoplanin and CD9 is reduced following
VEGF-C stimulation whereas the association between podoplanin and integrin β1
increases. Podoplanin and VEGF-3 weakly colocalise and this does not change following
VEGF-C stimulation. CD9 and integrin β1 colocalise and VEGF-C increases their degree
of colocalisation.
Conclusion
Crosstalk between podoplanin and VEGF-C mediated signalling is modulated by
podoplanin ligation. Changes in CD9 and integrin β1 interactions with podoplanin may
modulate podoplanin and VEGF-C-mediated signalling. This highlights a potential
molecular mechanism through which podoplanin-dependent signalling may regulate
VEGF-C-mediated signalling and cellular functions
The case for early, time-sensitive speech, language, and communication interventions for young children with Down syndrome or other intellectual and developmental disabilities
The aim of this chapter is to stress the importance for speech, language, and communication interventions to begin in the first year of life for children with intellectual and developmental disabilities (IDD). In the chapter, we review the early foundations and development of neurotypical children’s speech, language, and communication skills. While patterns of development vary for children with IDD, all children tend to build their communication skills in much the same developmental order. Therefore, we argue that a sound knowledge of neurotypical development is the basis for understanding the challenges of those with IDD and designing tailored interventions. We identify that learning to communicate is not just influenced by the child’s abilities or challenges, but by the learning environment that they are in, including their daily communication interactions with caregivers. Thus, it is imperative to involve caregivers in the delivery of early interventions.
We illustrate our viewpoint by considering the example of children with Down syndrome whose speech, language, and communication difficulties are extensively documented. We provide a review of their challenges and of the evidence for early interventions to date. We then present two examples of interventions, both starting in the first year of life, that have been piloted to improve outcomes for this group of children. Both projects focus on supporting parents to implement the interventions and make use of digital technologies.
We present these as models, which illustrate the possibilities for starting interventions early and suggest they could be used with many other children with IDD known to be at risk for speech, language, and communication difficulties. We identify how they fit with expert recommendations for early and intensive interventions, how they can be upscaled with limited resources, and how they illustrate a ‘precision and individualized medicine’ approach
Validity of a wrist-worn consumer-grade wearable for estimating energy expenditure, sedentary behaviour, and physical activity in manual wheelchair users with spinal cord injury
Purpose
To evaluate the validity of a consumer-grade wearable for estimating energy expenditure, sedentary behaviour, and physical activity in manual wheelchair users with spinal cord injury (SCI).
Materials and methods
Fifteen manual wheelchair users with SCI (C5-L1, four female) completed activities of daily living and wheelchair propulsion (2–8 km·h−1). Wrist-worn accelerometry data were collected using consumer-grade (z-Track) and research-grade (ActiGraph GT9X) devices. Energy expenditure was measured via indirect calorimetry. Linear regression was used to evaluate the prediction of criterion metabolic equivalent of task (MET) by each accelerometer’s vector magnitude (VM). Area under the receiver operating characteristic curve (ROC-AUC) evaluated the accuracy of VM for discriminating between physical activity intensities and for identifying accelerometer cut-points.
Results
Standardised β-coefficients for the association between z-Track and ActiGraph VM for criterion MET were 0.791 (p < 0.001) and 0.774 (p < 0.001), respectively. The z-Track had excellent accuracy for classifying time in sedentary behaviour (ROC-AUC = 0.95) and moderate-to-vigorous physical activity (ROC-AUC = 0.93); similar values to the ActiGraph (ROC-AUC = 0.96 and 0.88, respectively). Cut-points for the z-Track were ≤37 g·min−1 for sedentary behaviour and ≥222 g·min−1 for moderate-to-vigorous physical activity.
Conclusions
This study supports the validity of a consumer-grade wearable to measure sedentary time and physical activity in manual wheelchair users with SCI
Why study in English? Teachers’ and students’ perceptions of EMI policy and motivations at Turkish universities
Increasingly, English is used as a medium of instruction (EMI) at universities in non-Anglophone countries to teach academic subjects other than English itself (Macaro, 2018). Driven by trends toward the internationalization of higher education, EMI programs are often assumed to improve both students’ understanding of content knowledge and their English language skills. However, the degree to which EMI programs achieve these alleged dual aims remains unknown and highly debated (see Macaro et al., 2018a, for an overview). Moreover, there remains a lack of understanding in terms of how teachers and students perceive these dual aims with respect to EMI policy and the degree to which these dual aims affect their rationale or motivation for participating in EMI programs. An in-depth understanding of teachers’ and students’ perceptions of EMI policies and motivations for EMI is needed, given the role these stakeholders play in classroom-level implementation.
The study reported in this chapter addresses that research gap by exploring EMI teachers’ and students’ perceptions of EMI policies and their motivations (or reasons) for joining EMI programs, to better understand how they understand the complexities of language and content learning in EMI university settings. The chapter draws from qualitative data gathered for a larger project which investigated EMI implementation in Turkish higher education. The study reported here relates specifically to teachers’ and students’ perceptions of EMI policy and perceptions of EMI motivations using data collected from interviews with teachers (n = 21) and focus group discussions with students (n = 150) in Engineering Faculties at seven universities in Turkey