2,889 research outputs found
Polyamide/Polyimide Aerogels
An aerogel and method of making the aerogel is disclosed. The aerogel is a polyimide/polyamide hybrid with a cross-linking agent that induces gelation
Comparing Vegetation Monitoring Methods in Shrublands: How Valuable is Grant’s Method in Shrub Communities?
Faced with managing extensive rangelands, land managers need reliable monitoring methods. Grant and others (2004) proposed a monitoring method that uses a floristic classification of dominant vegetation and assesses species frequency. The method was developed in native grass prairies with limited woody vegetation and is designed to provide more efficient repetitive monitoring. Our objective for this study was to determine if Grant’s method is useful in shrubland systems for a newly implemented baseline inventory and monitoring program. We conducted a study to compare Grant’s method and its efficacy to more commonly used line-point intercept in grass and shrub alliances at Brown’s Park National Wildlife Refuge, Colorado. In the summer of 2007 we conducted baseline inventory of vegetation characteristics on 39 permanent bottomland plots in six pre-determined grass and shrub vegetation alliances on the refuge. Within each plot, we monitored vegetation with line-point intercept and Grant’s method on three 50 m line transects. We compare data collected using these methods from a grassland (smooth brome dominated) and a shrubland (greasewood dominated) alliance. Results of this study indicate that data collected using Grant’s method is more variable than line-point intercept data in shrub systems. Bare ground was detected less using Grant’s than line-point intercept; however, Grant’s detected more herbaceous and invasive species overall than did the line-point intercept method. A complementary use of the methods for long-term monitoring is recommended that accommodates tradeoffs between incorporating detail versus efficiency of data collection efforts
Isolation of Plasmodium berghei ookinetes in culture using Nycodenz density gradient columns and magnetic isolation
BACKGROUND: Large scale in vitro production of the mosquito stages of malaria parasites remains elusive, with only limited success for complete sporogonic development and only one report of development through to infective sporozoites. The initial step in this process is the production, in vitro, of ookinetes from gametocytaemic blood. Methods for isolation of these ookinetes from blood cells have been described; however, in addition to yield often being low, processing time and potential for contamination by erythrocytes remain high. METHODS: This study compares two procedures for retaining mature ookinetes from blood stage cultures, whilst removing red blood cells and other contaminants prior to further culture of the parasite. The well established method of isolation on Nycodenz cushions is compared with a novel method utilizing the innate magnetic properties of the haem pigment crystals found in the cytoplasm of ookinetes. RESULTS: Yield and viability of ookinetes were similar with both isolation methods. However, in our hands magnetic isolation produced a cleaner ookinete preparation much more quickly. Moreover, decreasing the flow rate through the magnetic column could further enhance the yield. CONCLUSION: We recommend the enrichment of an ookinete preparation prior to further culture being performed using the magnetic properties of Plasmodium berghei ookinetes as an alternative to their density. The former technique is faster, removes more erythrocytes, but day-to-day costs are greater
Marshall University Music Department Presents a Woodwind Ensemble Recital
https://mds.marshall.edu/music_perf/1369/thumbnail.jp
Marshall University Music Department Presents a Woodwind Ensembles Recital
https://mds.marshall.edu/music_perf/1330/thumbnail.jp
Marshall University Music Department Presents the Woodwind Ensembles Recital
https://mds.marshall.edu/music_perf/1731/thumbnail.jp
Exacerbated inflammatory arthritis in response to hyperactive gp130 signalling is independent of IL-17A
Objective Interleukin (IL)-17A producing CD4 T-cells
(TH-17 cells) are implicated in rheumatoid arthritis (RA).
IL-6/STAT3 signalling drives TH-17 cell differentiation,
and hyperactive gp130/STAT3 signalling in the gp130F/F
mouse promotes exacerbated pathology. Conversely,
STAT1-activating cytokines (eg, IL-27, IFN-γ) inhibit
TH-17 commitment. Here, we evaluate the impact of
STAT1 ablation on TH-17 cells during experimental
arthritis and relate this to IL-17A-associated pathology.
Methods Antigen-induced arthritis (AIA) was
established in wild type (WT), gp130F/F mice displaying
hyperactive gp130-mediated STAT signalling and the
compound mutants gp130F/F:Stat1−/− and gp130F/F:
Il17a−/− mice. Joint pathology and associated peripheral
TH-17 responses were compared.
Results Augmented gp130/STAT3 signalling enhanced
TH-17 commitment in vitro and exacerbated joint
pathology. Ablation of STAT1 in gp130F/F mice (gp130F/F:
Stat1−/−
) promoted the hyperexpansion of TH-17 cells in
vitro and in vivo during AIA. Despite this heightened
peripheral TH-17 cell response, disease severity and the
number of joint-infiltrating T-cells were comparable with
that of WT mice. Thus, gp130-mediated STAT1 activity
within the inflamed synovium controls T-cell trafficking
and retention. To determine the contribution of IL-17A,
we generated gp130F/F:IL-17a−/− mice. Here, loss of
IL-17A had no impact on arthritis severity.
Conclusions Exacerbated gp130/STAT-driven disease in
AIA is associated with an increase in joint infiltrating
T-cells but synovial pathology is IL-17A independent
Cervical Cancer Survival by Socioeconomic Status, Race/Ethnicity, and Place of Residence in Texas, 1995–2001
Objective: The current study explored whether socioeconomic status (SES), race/ethnicity, and rural residence may be linked to poorer cervical cancer survival by stage at diagnosis.
Methods: Data from 7,237 cervical cancer cases reported to the Texas Cancer Registry from 1995–2001 were used to address the association by stage at diagnosis and cause of death. Zip code-level census data were used to classify residence and to develop a composite variable for SES. Multilevel Cox proportional hazards modeling was used to estimate hazard ratios
(HR) and 95% confidence intervals (CI).
Results: Late stage at diagnosis was a strong predictor of cervical cancer mortality (HR _6.2, 95% CI 5.5-7.2). SES and race/ethnicity were independently associated with stage at diagnosis. Women residing in areas with lower SES had significantly shorter survival times when diagnosed at an early stage (HR _ 3.0, 95% CI 2.1-4.3). Hispanic women had a lower probability of dying from cervical cancer during the follow-up period (HR _ 0.7, 95% CI 0.6- 0.8) after adjusting for confounders. The association between lower SES and poorer survival was consistent across all racial/ethnic groups, suggesting the effect of SES may be more important than race.
Conclusions: SES and race/ethnicity were independently associated with poorer cervical cancer survival in this large Texas sample. Further research is needed to investigate the role of optimal treatment and comorbid conditions in the association between SES and cervical cancer survival
Dispensary level pilot implementation of rapid diagnostic tests: an evaluation of RDT acceptance and usage by providers and patients – Tanzania, 2005
BACKGROUND\ud
\ud
Malaria rapid diagnostic tests (RDTs) may assist in diagnosis, improve prescribing practices and reduce potential drug resistance development. Without understanding operational issues or acceptance and usage by providers and patients, the costs of these tests may not be justified.\ud
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OBJECTIVES\ud
\ud
To evaluate the impact of RDTs on prescribing behaviours, assess prescribers' and patients' perceptions, and identify operational issues during implementation.\ud
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METHODS\ud
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Baseline data were collected at six Tanzanian public dispensaries. RDTs were implemented for eight weeks and data collected on frequency of RDT use, results, malaria diagnoses and the prescription of antimalarials. Patients referred for RDTs completed a standardised exit interview. Qualitative methods assessed attitudes toward and satisfaction with RDTs, perceptions about the test and operational issues related to implementation.\ud
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RESULTS\ud
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Of 595 patients at baseline, 200 (33%) were diagnosed clinically with malaria but had a negative RDT. Among the 2519 RDTs performed during implementation, 289 (11.5%) had a negative result and antimalarials prescribed. The proportion of "over-prescriptions" at baseline was 54.8% (198/365). At weeks four and eight this decreased to 16.1% (27/168) and 16.4% (42/256) respectively.A total of 355 patient or parent/caregiver and 21 prescriber individual interviews and 12 focus group discussions (FGDs) were conducted. Patients, caregivers and providers trusted RDT results, agreed that use of RDTs was feasible at dispensary level, and perceived that RDTs improved clinical diagnosis. Negative concerns included community suspicion and fear that RDTs were HIV tests, the need for additional supervision in interpreting the results, and increased work loads without added compensation.\ud
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CONCLUSION\ud
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Overprescriptions decreased over the study period. There was a high degree of patient/caregiver and provider acceptance of and satisfaction with RDTs. Implementation should include community education, sufficient levels of training and supervision and consideration of the need for additional staff
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Putting Fisheries and Aquaculture on Nepad Agenda
Capture fisheries is a primary employment for inhabitants of coastal and inland aquatic ecosystems globally. However, historically, aquaculture has been well documented as an economic activity in Southeast Asia. Coastal marine fisheries and freshwater inland waters provided employment for inhabitants of these ecosystems in Sub-Saharan Africa (SSA). Aquaculture was started in Africa over four decades ago. Yet, the activities have not substantially contributed to domestic fish production, hence, the need for the hosting of the NEPAD Fish for All Summit by President Olusegun Obasanjo of Nigeria in Abuja, August 2005. The Summit ended with a unanimously adopted Abuja Declaration. This is a positive strategy for putting fisheries and aquaculture on NEPAD's Future Actions in the process of developing Agriculture in all 53 SSA countries. This paper examined the issues that will enhance the objectives of putting fisheries and aquaculture on the future agenda of NEPAD. Nigeria's fisheries and aquaculture was used as an example for the implementation of the Abuja Declaration as a follow-up action. The Private and Public Sector contributions to a successful action plan are extensively discussed. Recommendations hinge on the issues inhibiting farming Nigeria’s waters for economic growth as a nation and as a unique market for fisheries and aquaculture in West and Central Africa
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