1,315 research outputs found

    Evaluating an analytical model to predict subsurface LNAPL distributions and transmissivity from current and historic fluid levels in groundwater wells: Comparing results to numerical simulations

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    A recent analytical model predicts free, entrapped, and residual LNAPL saturations and the LNAPL transmissivity in the subsurface from current and historic fluid levels in groundwater wells. As such, the model accounts for effects of fluid level fluctuations in a well. The model was developed to predict LNAPL specific volumes and transmissivities from current fluid level measurements in wells and either recorded historic fluid level fluctuations in wells or estimates. An assumption is made in the model that the predictions are not dependent on whether the historic highest or lowest fluid level elevations in a well occur first. To test the assumption, we conduct two simulations with a modified multiphase flow numerical code TMVOC that incorporates relative permeability-saturation-capillary head relations employed in the model. In one simulation, the initial condition is for fluid levels in a well at the historic highest elevations. In the other simulation, the initial condition is for fluid levels in a well at the historic lowest elevations. We change the boundary conditions so both historical conditions occur followed by generating the current condition. Results from the numerical simulations are compared to model predictions and show the assumption in the analytical model is reasonable. The analytical model can be used to develop/refine conceptual site models and for assessing potential LNAPL recovery endpoints, especially on sites with fluctuating fluid levels in wells

    Predictive modeling of plant messenger RNA polyadenylation sites

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    BACKGROUND: One of the essential processing events during pre-mRNA maturation is the post-transcriptional addition of a polyadenine [poly(A)] tail. The 3'-end poly(A) track protects mRNA from unregulated degradation, and indicates the integrity of mRNA through recognition by mRNA export and translation machinery. The position of a poly(A) site is predetermined by signals in the pre-mRNA sequence that are recognized by a complex of polyadenylation factors. These signals are generally tri-part sequence patterns around the cleavage site that serves as the future poly(A) site. In plants, there is little sequence conservation among these signal elements, which makes it difficult to develop an accurate algorithm to predict the poly(A) site of a given gene. We attempted to solve this problem. RESULTS: Based on our current working model and the profile of nucleotide sequence distribution of the poly(A) signals and around poly(A) sites in Arabidopsis, we have devised a Generalized Hidden Markov Model based algorithm to predict potential poly(A) sites. The high specificity and sensitivity of the algorithm were demonstrated by testing several datasets, and at the best combinations, both reach 97%. The accuracy of the program, called poly(A) site sleuth or PASS, has been demonstrated by the prediction of many validated poly(A) sites. PASS also predicted the changes of poly(A) site efficiency in poly(A) signal mutants that were constructed and characterized by traditional genetic experiments. The efficacy of PASS was demonstrated by predicting poly(A) sites within long genomic sequences. CONCLUSION: Based on the features of plant poly(A) signals, a computational model was built to effectively predict the poly(A) sites in Arabidopsis genes. The algorithm will be useful in gene annotation because a poly(A) site signifies the end of the transcript. This algorithm can also be used to predict alternative poly(A) sites in known genes, and will be useful in the design of transgenes for crop genetic engineering by predicting and eliminating undesirable poly(A) sites

    Integrating WASH and nutrition in market-based interventions: principles and results from the field

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    This paper outlines principles for integrating market-based approaches for improving WASH and nutrition. It draws on iDE’s experience implementing such programs, and specifically highlights learnings from iDE Bangladesh’s program Profitable Opportunities for Food Security (PROOFS), implemented in partnership with ICCO Cooperation, BoP Inc., and Edukans. PROOFS leverages market forces to increase food security, nutrition, and water and sanitation for smallholder farmers and base-ofpyramid consumers. The program recently concluded a pilot in which Nutrition Sales Agents added a set of WASH products to their existing “basket” of nutrition-related goods. The paper highlights principles for leveraging markets to achieve outcomes in WASH and nutrition. Specific insights involve aligning sales cycles, managing different sales and distribution channels, and ensuring that product margins provide profit opportunity for businesses and sales agents. These principles are underscored by observations from the WASH-Nutrition pilot, the final results of which will be available for the WEDC Conference

    Natural source zone depletion of LNAPL: A critical review supporting modelling approaches

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    Natural source zone depletion (NSZD) of light non-aqueous phase liquids (LNAPLs) includes partitioning, transport and degradation of LNAPL components. NSZD is being considered as a site closure option during later stages of active remediation of LNAPL contaminated sites, and where LNAPL mass removal is limiting. To ensure NSZD meets compliance criteria and to design enhanced NSZD actions if required, residual risks posed by LNAPL and its long term behaviour require estimation. Prediction of long-term NSZD trends requires linking physicochemical partitioning and transport processes with bioprocesses at multiple scales within a modelling framework. Here we expand and build on the knowledge base of a recent review of NSZD, to establish the key processes and understanding required to model NSZD long term. We describe key challenges to our understanding, inclusive of the dominance of methanogenic or aerobic biodegradation processes, the potentially changeability of rates due to the weathering profile of LNAPL product types and ages, and linkages to underlying bioprocesses. We critically discuss different scales in subsurface simulation and modelling of NSZD. Focusing on processes at Darcy scale, 36 models addressing processes of importance to NSZD are investigated. We investigate the capabilities of models to accommodate more than 20 subsurface transport and transformation phenomena and present comparisons in several tables. We discuss the applicability of each group of models for specific site conditions

    Classification of first branchial cleft anomalies: is it clinically relevant?

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    Background: There are three classification systems for first branchial cleft anomalies currently in use. The Arnot, Work and Olsen classifications describe these lesions on the basis of morphology, tissue of origin and clinical appearance. However, the clinical relevance of these classifications is debated, as they may not be readily applicable in all cases and may provide no additional information on how the lesion should be managed.Objective: We seek to investigate this issue by applying these classification systems to cases from our centre and evaluating the information gained.Patients and methods: A retrospective case note review of all first branchial cleft anomalies excised at our institution between 2004 and 2014 was carried out, recording patient demographics, information on the anomalies and how they were investigated and managed.Results: This search identified eight unilateral cases and one bilateral case of first branchial cleft anomalies. These were a heterogenous group of lesions, which were variably investigated and managed. Categorization of these cases into Arnot, Work and Olsen subtypes did not correlate with the lesion’s relation with the facial nerve or the outcome of excision.Conclusion: The current classification systems used for first branchial cleft anomalies have little clinical relevance apart from providing extensive descriptions to aid in diagnosis. We advise instead that clinicians use imaging techniques to gain as much information as possible about these lesions before excision and be aware of the risk to the facial nerve at the time of excision. A description of the lesion’s relation with the facial nerve at the time of excision may provide more information on the likely outcomes compared with the classifications currently in use.Keywords: branchial cleft, congenital anomaly, facial nerve injury, first branchial cleft anomal

    Correction to: Improved X-ray baggage screening sensitivity with 'targetless' search training.

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    Funder: Defence and Security Accelerator; doi: http://dx.doi.org/10.13039/100012339Abstract: When searching for a known target, mental representations of target features, or templates, guide attention towards matching objects and facilitate recognition. When only distractor features are known, distractor templates allow irrelevant objects to be recognised and attention to be shifted away. This is particularly true in X-ray baggage search, a challenging real-world visual search task with implications for public safety, where targets may be unknown, difficult to predict and concealed by an adversary, but distractors are typically benign and easier to identify. In the present study, we draw on basic principles of distractor suppression and rejection to investigate a counterintuitive ‘targetless’ approach to training baggage search. In a simulated X-ray baggage search task, we observed significant benefits to target detection sensitivity (dâ€Č) for targetless relative to target-based training, but no effects of performance-contingent rewards or the inclusion of superordinate semantic categories during training. The benefits of targetless search training were most apparent for stimuli involving less spatial overlap (occlusion), which likely represents the difficulty and greater individual variation involved in searching more visually complex images. Together, these results demonstrate the effectiveness of a counterintuitive targetless approach to training target detection in X-ray baggage search, based on basic principles of distractor suppression and rejection, with potential for use as a real-world training tool

    Prospectus, May 19, 1975

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    MCMULLEN WINS PRESIDENCY; PC News
.In Brief: Library Extends Hours, Registration By Mail Deadline May 27, New Officers For Chi Gamma; StuGo Budget Vetoed; VP Race Squeaker; Betty Furness To Address Grads; Dental Students Capped; Statutory Rape: Crime Without A Victim; StuGo Minutes; More StuGo Minutes; Fine Arts Week At Parkland; $9000...Where Does The Priority Lie?; The Kaleidoscope; The Short Circuit; letters; L.T.D.s Corner: OFF Without A Hitch...Almost; To The 1975 College Grads; Parkland: The Year In Review; Le Finis; Skylines; Chess Talk: Chess Notation; Congratulations to Mrs. Teresa Wells...; It\u27s Not Too Late For A Summer Job In Europe; Cimmeron Brings Insane Happiness; Suggestion Box; Wiechman Recieves ROTC Scholarship; What If...; Movie Revue: \u27Shampoo\u27; May 22nd: \u27Slink Rand\u27; Zappa Captivates Chicago; My Friendly Tree; Wanted: Reporters; Student Elections: Opinion Poll; S.I.U. Has New LibTech Program; Fine Arts Week; Classified Ads; Outside Life At PC; NROTC Scholarship Pgrogram; New Record For Bike Race; Sports Views; Trackmen Third In State; Cobras\u27 Win Streak Broken; Final Examination Schedule; Problems? Learning Lab Can Help; New Pharmacology Class; Awards Given At IOC Banquethttps://spark.parkland.edu/prospectus_1975/1009/thumbnail.jp

    Syncrip/hnRNP Q influences synaptic transmission and regulates BMP signaling at the Drosophila neuromuscular synapse

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    Synaptic plasticity involves the modulation of synaptic connections in response to neuronal activity via multiple pathways. One mechanism modulates synaptic transmission by retrograde signals from the post-synapse that influence the probability of vesicle release in the pre-synapse. Despite its importance, very few factors required for the expression of retrograde signals, and proper synaptic transmission, have been identified. Here, we identify the conserved RNA binding protein Syncrip as a new factor that modulates the efficiency of vesicle release from the motoneuron and is required for correct synapse structure. We show that syncrip is required genetically and its protein product is detected only in the muscle and not in the motoneuron itself. This unexpected non-autonomy is at least partly explained by the fact that Syncrip modulates retrograde BMP signals from the muscle back to the motoneuron. We show that Syncrip influences the levels of the Bone Morphogenic Protein ligand Glass Bottom Boat from the post-synapse and regulates the pre-synapse. Our results highlight the RNA-binding protein Syncrip as a novel regulator of synaptic output. Given its known role in regulating translation, we propose that Syncrip is important for maintaining a balance between the strength of presynaptic vesicle release and postsynaptic translation
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