196 research outputs found
Larval Performance in Relation to Labile Oviposition Preference of Crocidolomia pavonana [F.] (Lepidoptera: Pyralidae) Among Phenological Stages of Cabbage
Crocidolomia pavonana (=binotalis) [F.] demonstrates oviposition peaks in the field that we believe to be correlated with host plant phenology. In previous two-choice laboratory experiments, we found the highest relative proportion of oviposition on cabbage to correspond either to plant growth stages ≈7–8 wk or ≈9–11 wk old, depending on the alternate host plant with which it was presented. In cabbage-only trials, leaves from 7- to 8-wk-old plants were preferred. Inconsistency in preference led to the question of whether oviposition on either cabbage growth stage would confer adaptive advantages in offspring performance. We simulated oviposition on four phenological stages of cabbage in two ways. In a study of complete immature development, growth rate, pupal weight, and survivorship were measured. We also compared food utilization efficiency during the fourth larval instar by analyzing growth rate, efficiency of biomass accumulation, and frass production by analysis of covariance (ANCOVA). For both experiments, cabbage plants of defined phenological stages were designated at the time of oviposition, and larvae were fed from these as plants continued to grow throughout larval development. Our data indicate adaptive advantages in larval growth rate and food conversion efficiency to oviposition on cabbage at ≈7–8 wk from planting. Oviposition on later cabbage growth stages resulted in comparatively poor larval performance. Possible explanations for C. pavonana oviposition behavior in light of these results are discusse
Effects of Host Plant Phenology on Oviposition Preference of Crocidolomia pavonana (Lepidoptera: Pyralidae)
Field studies have demonstrated mixed success in trap cropping to manage Crocidolomia pavonana (=binotalis) [F.], a major pest of cruciferous crops in Asia. A possible explanation for this is an influence of host plant phenology on oviposition preference. We tested this in simultaneous two-choice oviposition bioassays under laboratory conditions. In cylindrical cardboard experimental arenas, with 5-cm2 leaf windows, individual C. pavonana females were offered eight sequential phenological stages of cabbage (Brassica oleracea L., Capitata group, cultivar Gloria) with a constant stage of preflowering Indian mustard (Brassica juncea, variety rugosa, cultivar Green Wave). Results showed a significant effect of cabbage developmental stage on oviposition preference. We continued with two-choice bioassays, using whole leaves, in screen cage experimental arenas. Females were offered the three most preferred phenological stages of cabbage and differing stages of four potential trap crop alternatives: preflowering Indian mustard; preflowering Chinese cabbage (B. rapa L., variety pekinensis [Lour.] Olsson); preflowering, flowering, and "with silique” sawi manis (B. rapa, variety parachinensis [Bailey] Tsen and Lee); and preflowering and flowering sayur pahit (B. rapa, variety parachinensis [Bailey] Tsen and Lee). Results indicated that the phenological stages of both plants had a significant effect on relative oviposition preference. However, patterns of preference changed in the context of the different plant species combinations. In addition, implicit hierarchical preference order was frequently contradicted. These results have implications for the improvement of trap cropping strategies to manage C. pavonana and for the potential success of biological control of Plutella xylostella [L.], where these pests occur in comple
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Site Investigation and Evaluation of Remedial Alternatives for the Wharton County Site, East Bernard, Texas
The permitting process for salt-water injection wells mandates that oil companies or operators conduct an Area of Review (AOR) study within a 0.25-mile radius of a proposed well. The objective of such a study is to identify unplugged wells that could potentially allow injected fluids to migrate upward from the production zone, posing a threat to the overlying underground sources of drinking water (USDW).
The Bureau of Economic Geology (BEG) at the University of Texas at Austin, working in collaboration with the Railroad Commission of Texas (RRC), assessed oil fields across Texas to determine if any variations to the AOR permitting process were feasible based on the separation between production-zone fluid levels and the base of USDW. This evaluation aimed to provide the RRC and the industry with valuable data and methodology to facilitate AOR variance applications and the review of oil fields in Texas.Bureau of Economic Geolog
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Potential Sinks for Geologic Storage of CO2 Generated in the Carolinas
This document summarizes a scoping study of the current state of knowledge of carbon storage options for our geographic area.
The focus is on one aspect of carbon capture and storage—identification of deep saline aquifers in which carbon dioxide (CO2
) generated in the Carolinas might be stored. The study does not address other aspects of CO2 storage projects, such as capture and compression of the gas, well construction and development, or injection. Transport of CO2 is touched upon in this study but has not been fully addressed.
The information contained in this document is primarily from review of published geologic literature and unpublished data. No field data collection has been completed as part of this study. Further work will be necessary to increase confidence in the suitability of the potential CO2 storage sites identified in this report. This study does not address the regulatory, environmental, or public policy issues associated with carbon storage, which are under development at this time.Duke Energy, Progress Energy, Santee Cooper Power, South Carolina Electric and Gas, Electric Power Research Institute (EPRI), Southern States Energy Board (SSEB)Bureau of Economic Geolog
Telehealth after the pandemic: Will the inverse care law apply? (Commentary)
The COVID-19 pandemic has accelerated the use of telehealth within the cystic fibrosis (CF) community to deliver CF care. The article by Solomon and colleagues exploring the patient and family experiences of telehealth care delivery, as part of the CF chronic care model in the US, is therefore timely. In this commentary, we discuss how the US experience of telehealth care compares with reports from CF centres in other parts of the world. We highlight the potential challenges, including whether the inverse care law will apply in this new era of CF telehealth
Vibroacoustic stimulation for fetal assessment in labour in the presence of a nonreassuring fetal heart rate trace (Review)
Background: Fetal vibroacoustic stimulation (VAS) is a simple, non-invasive technique where a device is placed on the maternal abdomen over the region of the fetal head and sound is emitted at a predetermined level for several seconds. It is hypothesised that the resultant startle reflex in the fetus and subsequent fetal heart rate (FHR) acceleration or transient tachycardia following VAS provide reassurance of fetal well-being. This technique has been proposed as a tool to assess fetal well-being in the presence of a nonreassuring cardiotocographic (CTG) trace during the first and second stages of labour. Objectives: To evaluate the clinical effectiveness and safety of VAS in the assessment of fetal well-being during labour, compared with mock or no stimulation for women with a singleton pregnancy exhibiting a nonreassuring FHR pattern. Search methods: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (6 September 2012) and reference lists of all retrieved articles. We sought unpublished trials and abstracts submitted to major international congresses and contacted expert informants. Selection criteria: All published and unpublished randomised trials that compared maternal and fetal/neonatal/infant outcomes when VAS was used to evaluate fetal status in the presence of a nonreassuring CTG trace during labour, compared with mock or no stimulation. Data collection and analysis: Two review authors independently sought to assess for inclusion all the potential studies we identified as a result of the search strategy. We planned to resolve any disagreement through discussion or, if required, to consult a third person. Where there was uncertainty about a particular study, we attempted to contact study authors for additional information. However, these attempts were unsuccessful. Main results: The search strategies yielded six studies for consideration of inclusion. However, none of these studies fulfilled the requirements for inclusion in this review. Authors' conclusions: There are currently no randomised controlled trials that address the safety and efficacy of VAS used to assess fetal well-being in labour in the presence of a nonreassuring CTG trace. Although VAS has been proposed as a simple, non-invasive tool for assessment of fetal well-being, there is insufficient evidence from randomised trials on which to base recommendations for use of VAS in the evaluation of fetal well-being in labour in the presence of a nonreassuring CTG trace
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Understanding and Managing Environmental Roadblocks to Shale Gas Development: An Analysis of Shallow Gas, NORM, and Trace Metals
The main objective of the project was to document occurrences of shallow gas in fresh-water aquifers in Texas either dissolved or free phase and identify controlling processes. A secondary somewhat independent objective was to contribute to the understanding of the nature and variability of flowback and produced water associated with hydraulic fracturing in the context of rock-water interactions.
We undertook a large sampling campaign of aquifers in the footprint of major Texas plays (900+ water samples): Barnett in north-central Texas (555 unique locations), Eagle Ford in South Texas (118 unique locations), Haynesville in East Texas (70 unique locations), and in the Delaware Basin of West Texas (40 unique locations). Most of the wells (2/3) are relatively shallow residential wells sampled at or as close as possible to the wellhead but many wells are irrigation, municipal, or rig-supply wells. All samples were analyzed for major ions, dissolved gases, and, when CH4 > 0.1 mg/L, for methane and light alkanes carbon isotopes and trace elements. The vast majority of wells show some measurable methane and ~100 wells show methane > 0.1 mg/L. A total of ~20 wells have methane concentrations > 10 mg/L, these high concentrations were observed in all plays and present at least a thermogenic component. Some wells, generally with a < 10 mg/L concentration, show a clear microbial origin for methane. A number of samples show mixing between the two origins but also more complex behavior such as methane degradation. Samples with thermogenic methane are generally spatially organized in clusters. Overall the source of the dissolved methane is likely natural sourced from shallow natural gas accumulations in the Barnett Shale, lignite beds associated with a fault in the Haynesville shale, and lignite and degradation of oil and deep organic matter associated with a fractured zone in the Eagle Ford Shale. The Delaware Basin samples show no dissolved methane other than associated to a recent blowout.
We also performed autoclave experiments in controlled conditions exposing shale core fragments to various fluids, examining reacted and unreacted rocks and documenting chemical composition of the evolving fluid through time. The experiments demonstrated that shales undergo typical geochemical processes during hydraulic fracturing such as carbonate and feldspar dissolution as well as ion exchange resulting in an increase in dissolved solids. Observations suggest that rock permeability is increased two to three-fold and that porosity is increased by 50%.
Baseline sampling as it is currently practiced is not sufficient to resolve ambiguity of the source of the dissolved methane even if of thermogenic origin because it still could be natural. Additional analyses such as noble gases and isotopes are needed to better constrain origin of the methane.Bureau of Economic Geolog
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The candidate genes TAF5L, TCF7, PDCD1, IL6 and ICAM1 cannot be excluded from having effects in type 1 diabetes.
BACKGROUND: As genes associated with immune-mediated diseases have an increased prior probability of being associated with other immune-mediated diseases, we tested three such genes, IL23R, IRF5 and CD40, for an association with type 1 diabetes. In addition, we tested seven genes, TAF5L, PDCD1, TCF7, IL12B, IL6, ICAM1 and TBX21, with published marginal or inconsistent evidence of an association with type 1 diabetes. METHODS: We genotyped reported polymorphisms of the ten genes, nonsynonymous SNPs (nsSNPs) and, for the IL12B and IL6 regions, tag SNPs in up to 7,888 case, 8,858 control and 3,142 parent-child trio samples. In addition, we analysed data from the Wellcome Trust Case Control Consortium genome-wide association study to determine whether there was any further evidence of an association in each gene region. RESULTS: We found some evidence of associations between type 1 diabetes and TAF5L, PDCD1, TCF7 and IL6 (ORs = 1.05 - 1.13; P = 0.0291 - 4.16 x 10-4). No evidence of an association was obtained for IL12B, IRF5, IL23R, ICAM1, TBX21 and CD40, although there was some evidence of an association (OR = 1.10; P = 0.0257) from the genome-wide association study for the ICAM1 region. CONCLUSION: We failed to exclude the possibility of some effect in type 1 diabetes for TAF5L, PDCD1, TCF7, IL6 and ICAM1. Additional studies, of these and other candidate genes, employing much larger sample sizes and analysis of additional polymorphisms in each gene and its flanking region will be required to ascertain their contributions to type 1 diabetes susceptibility.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
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Assessment of Geological Storage Capacity of the Southeastern U.S. for CO2 in Brines and Economic Use for EOR
Bureau of Economic Geolog
Complex roles of TGF-beta signaling pathways in lung development and bronchopulmonary dysplasia
As survival of extremely preterm infants continues to improve, there is also an associated increase in bronchopulmonary dysplasia (BPD), one of the most significant complications of preterm birth. BPD development is multifactorial resulting from exposure to multiple antenatal and postnatal stressors. BPD has both short-term health implications and long-term sequelae including increased respiratory, cardiovascular and neurological morbidity. Transforming growth factor beta (TGF-b) is an important signaling pathway in lung development, organ injury and fibrosis and is implicated in the development of BPD. This review provides a detailed account on the role of TGF-b in antenatal and postnatal lung development, the effect of known risk factors for BPD on the TGF-b signaling pathway, and how medications currently in use or under development, for the prevention or treatment of BPD, affect TGF-b signaling
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