309 research outputs found
Sensor-Based Soil Water Monitoring to More Effectively Manage Agricultural Water Resources in Coastal Plain Soils
Cotton (Gossypium hirsutum L.) is widely grown in the United States with 5.7 million ha grown nationally and 1.2 million ha grown in the humid southeastern states in 2005. From 1969 to 2003, agricultural irrigated farmland acreage and total water applied increased by over 40% and 11% respectively to include a total of 55.3 million acres in 2002. Combined with recent and more frequent drought periods and legal water conflicts between states, there has been an increased interest in more effective southeastern water management, thus making the need to develop improved irrigation scheduling methods and enhanced water use efficiency of cotton cultivars. Several irrigation scheduling methods (soil moisture monitoring, pan evaporation, and climate based) tested at Clemson and elsewhere have shown that sensor-based irrigation significantly increased cotton yields and provided a monetary savings compared to other methods. There is however limited information on capacitance based soil moisture analysis techniques in the southeastern coastal plain soils and also limited locally developed crop coefficients used in scheduling the ET based treatments. The first objective of this study was to determine and improve the feasibility of utilizing sensor-based soil water monitoring techniques in Southeastern Coastal Plain soils to more effectively manage irrigation and increase water use efficiency of several cotton cultivars. The second objective was to develop two weighing lysimeters equipped with wireless data acquisition system to determine a crop coefficient for cotton under southeastern humid conditions. Two multi-sensor capacitance probes, AquaSpyTM and Sentek EnviroSCAN Ā® , were calibrated in this study. It was found that positive linear calibrations can be used to describe the relationship between the soil volumetric moisture content (VMC) and sensor readings found for both probes and that multi-sensor capacitance probes can be used to accurately measure volumetric soil moisture contents, if installed and calibrated properly. It was determined that a direct installation method should be used rather than a slurry mix method. The slurry method was found to overestimate the VMC in sandy soils. There were good correlations between In Season Estimated Yield (INSEY) as measured by the plant Normalized Difference Vegetation Index (NDVI) and the VMC of the soil. Results showed that when separated by irrigation regime, the relationship between INSEY and VMC follows good linear correlations. This was due to the health of the plant and its dependency on soil moisture. There were strong correlations between irrigation depths applied and seed cotton yields. Highest water use efficiency values were 0.55kg seed cotton/m3 water applied in 2008 (0.55kg seed cotton/m3 ET) and 0.788kg/m3 water applied (0.66kg/m3 ET) in 2009. Two weighing lysimeters were constructed to provide cotton and reference ET measurements. Evaporation pan and weather data from a local station were also used to provide a basis for calculating ET. Because the Penman ā Monteith (P ā M) method is widely known and trusted, a set of crop coefficients were developed based on P ā M and cotton lysimeter data and determined to be 0.91, 1.24, and 0.72 for the initial, mid, and end stages for a Delta Pine 0949 BSRF cultivar
Categorical Cell Decomposition of Quantized Symplectic Algebraic Varieties
We prove a new symplectic analogue of Kashiwara's Equivalence from D-module
theory. As a consequence, we establish a structure theory for module categories
over deformation quantizations that mirrors, at a higher categorical level, the
Bialynicki-Birula stratification of a variety with an action of the
multiplicative group. The resulting categorical cell decomposition provides an
algebro-geometric parallel to the structure of Fukaya categories of Weinstein
manifolds. From it, we derive concrete consequences for invariants such as
K-theory and Hochschild homology of module categories of interest in geometric
representation theory.Comment: Version 2. A number of minor edits and corrections. Comments welcom
Independent regulation of P53 stabilisation and activation after Rb deletion in primary epithelial cells
We have previously reported that deletion of the retinoblastoma gene Rb leads to rapid but transient p53 stabilisation. We investigated here the pathways involved. We show that upon Rb-deletion dysregulated E2F activates p19(ARF) expression that localises in the nucleoli. There it interacts with MDM2, leading to P53 stabilisation. At the same time, ATR is activated, activating CHK1 that may phosphorylate P53 but also contribute to inhibition of MnSOD expression leading to accumulation of ROS (reactive oxygen species) and subsequent DNA injury, which in turn maintains ATR/CHK1 activated. However, from 72 h after Rb deletion, NPM interacts with P19ARF and concomitantly the interaction between p19(ARF) and MDM2 decreases leading to a return to P53 degradation. This occurs despite the persistence of the DNA damage response pathways. We therefore observe in primary cells not subjected to exogenous gene expression or exogenous DNA damaging treatment, activation of 2 concomitant pathways of activation of P53 that are dealt with in independent manner: an oncogenic pathway with rapid activation of ARF which is 'switched off' downstream of p19(ARF) activation after 72 h of induction and a DNA damage response pathway keeping a low level of transcriptionally active P53 sufficient to deal with a physiological elevation of oxidative DNA injury. A possible connection between the two pathways is discussed.Publisher PDFPeer reviewe
Deficiency of G1 regulators P53, P21Cip1 and/or pRb decreases hepatocyte sensitivity to TGFbeta cell cycle arrest
TGFbeta is critical to control hepatocyte proliferation by inducing G1-growth arrest through multiple pathways leading to inhibition of E2F transcription activity. The retinoblastoma protein pRb is a key controller of E2F activity and G1/S transition which can be inhibited in viral hepatitis. It is not known whether the impairment of pRb would alter the growth inhibitory potential of TGFbeta in disease. We asked how Rb-deficiency would affect responses to TGFbeta-induced cell cycle arrest.Publisher PDFPeer reviewe
Niches for Species, a multi-species model to guide woodland management: An example based on Scotland's native woodlands
Designating and managing areas with the aim of protecting biodiversity requires information on species distributions and habitat associations, but a lack of reliable occurrence records for rare and threatened species precludes robust empirical modelling. Managers of Scotlandās native woodlands are obliged to consider 208 protected species, which each have their own, narrow niche requirements. To support decision-making, we developed Niches for Species (N4S), a model that uses expert knowledge to predict the potential occurrence of 179 woodland protected species representing a range of taxa: mammals, birds, invertebrates, fungi, bryophytes, lichens and vascular plants. Few existing knowledge-based models have attempted to include so many species. We collated knowledge to define each speciesā suitable habitat according to a hierarchical habitat classification: woodland type, stand structure and microhabitat. Various spatial environmental datasets were used singly or in combination to classify and map Scotlandās native woodlands accordingly, thus allowing predictive mapping of each speciesā potential niche. We illustrate how the outputs can inform individual species management, or can be summarised across species and regions to provide an indicator of woodland biodiversity potential for landscape scale decisions. We tested the model for ten species using available occurrence records. Although concordance between predicted and observed distributions was indicated for nine of these species, this relationship was statistically significant in only five cases. We discuss the difficulties in reliably testing predictions when the records available for rare species are typically low in number, patchy and biased, and suggest future model improvements. Finally, we demonstrate how using N4S to synthesise complex, multi-species information into an easily digestible format can help policy makers and practitioners consider large numbers of species and their conservation needs
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UK landscape ecology: trends and perspectives from the first 25 years of ialeUK
Context
The 25th anniversary of the founding of the UK chapter of the International Association for Landscape Ecology (ialeUK) was marked in 2017.
Objectives
To assess trends in UK landscape ecology research over ialeUKās first 25 years, to compare these trends to changes elsewhere in the world, and to consider how ialeUK can continue to support landscape ecology research and practice.
Methods
A database of conference abstracts was compiled and examined in combination with a questionnaire that surveyed existing and former active members of ialeUK.
Results
Across 1992ā2017 we observe noticeable trends including the declining roles of statutory bodies, the development of the ecosystem services concept, and a decrease in use of empirical methods. Analysis of questionnaire results highlighted four key areas: Developing new researchers; Facilitating conferences for networking, learning and discussion; Linking policy with practice; and Driving the continued growth of landscape ecology as a discipline. Challenges were also noted, especially regarding the adoption of a wider understanding of landscape ecological principles in management.
Conclusions
Increases in qualitative research, decreases in studies explicitly examining connectivity/fragmentation and an absence of landscape genetics studies in the UK are seemingly distinct from US landscape ecology and elsewhere around the world, based on published accounts. ialeUK has had success in increasing the role of landscape ecology in policy and practice, but needs to continue to aim for improved collaboration with other landscape-related professional bodies and contributions to wider sustainability agendas
"Utopian in the right sense": The Responsibility to Protect and the Logical Necessity of Reform
In this article I argue that the claims made about the efficacy of the Responsibility to Protect (RtoP) echo the pejorative conceptions of āutopianismā advanced by E. H. Carr and Ken Booth, in two ways: by virtue of RtoPās supporterās determination to claim āprogressā in spite of countervailing empirical evidence, and the exaggerated importance supporters ascribe to institutionalization, which mistakenly conflates state support with a change in state behavior and interests. I argue that RtoPās impact on the behavior of states has been, and will continue to be, limited and that while RtoP has garnered widespread support amongst states, this is due to it having been rendered largely impotent through a process of norm co-optation. While both Carr and Booth criticized a particular form of utopianism, I demonstrate that both also defended the articulation of normative prescriptions that are not immediately feasible; to this end, I conclude by suggesting a potential reform of the existing international legal order that meets Carrās preference for normative thinking that is āutopian in the right senseā
Hemorrhagic stroke outcomes of KApSR patients with co-morbid diabetes and Alzheimerās disease
Background: Vascular risk factors, such as diabetes mellitus (DM), are associated with poorer outcomes following many neurodegenerative diseases, including hemorrhagic stroke and Alzheimerās disease (AD). Combined AD and DM co-morbidities are associated with an increased risk of hemorrhagic stroke and increased Medicare costs. Therefore, we hypothesized that patients with DM in combination with AD, termed DM/AD, would have increased hemorrhagic stroke severity.
Methods: Kentucky Appalachian Stroke Registry (KApSR) is a database of demographic and clinical data from patients that live in Appalachia, a distinct region with increased health disparities and stroke severity. Inpatients with a primary indication of hemorrhagic stroke were selected from KApSR for retrospective analysis and were separated into four groups: DM only, AD only, neither, or both.
Results: Hemorrhagic stroke patients (2,071 total) presented with either intracerebral hemorrhage (ICH), n=1,448, or subarachnoid hemorrhage (SAH), n=623. When examining all four groups, subjects with AD were significantly older (AD+, 80.9Ā±6.6 yrs) (DM+/AD+, 77.4Ā±10.0 yrs) than non AD subjects (DM-/AD-, 61.3Ā±16.5 yrs) and (DM+, 66.0Ā±12.5 yrs). A higher percentage of females were among the AD+ group and a higher percentage of males among the DM+/AD+ group. Interestingly, after adjusting for multiple comparison, DM+/AD+ subjects were ten times as likely to suffer a moderate to severe stroke based on a National Institute of Health Stroke (NIHSS) upon admission [odds ratio (95% CI)] compared to DM-/AD- [0.1 (0.02ā0.55)], DM+ [0.11 (0.02ā0.59)], and AD+ [0.09(0.01ā0.63)]. The odds of DM+/AD+ subjects having an unfavorable discharge destination (death, hospice, long-term care) was significant (P
Conclusions: In our retrospective analysis utilizing KApSR, regardless of adjusting for age, sex, and comorbidities, DM+/AD+ patients were significantly more likely to have had a moderate or severe stroke leading to an unfavorable outcome following hemorrhagic stroke
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