45 research outputs found
Proceedings of the 3rd Biennial Conference of the Society for Implementation Research Collaboration (SIRC) 2015: advancing efficient methodologies through community partnerships and team science
It is well documented that the majority of adults, children and families in need of evidence-based behavioral health interventionsi do not receive them [1, 2] and that few robust empirically supported methods for implementing evidence-based practices (EBPs) exist. The Society for Implementation Research Collaboration (SIRC) represents a burgeoning effort to advance the innovation and rigor of implementation research and is uniquely focused on bringing together researchers and stakeholders committed to evaluating the implementation of complex evidence-based behavioral health interventions. Through its diverse activities and membership, SIRC aims to foster the promise of implementation research to better serve the behavioral health needs of the population by identifying rigorous, relevant, and efficient strategies that successfully transfer scientific evidence to clinical knowledge for use in real world settings [3]. SIRC began as a National Institute of Mental Health (NIMH)-funded conference series in 2010 (previously titled the âSeattle Implementation Research Conferenceâ; $150,000 USD for 3 conferences in 2011, 2013, and 2015) with the recognition that there were multiple researchers and stakeholdersi working in parallel on innovative implementation science projects in behavioral health, but that formal channels for communicating and collaborating with one another were relatively unavailable. There was a significant need for a forum within which implementation researchers and stakeholders could learn from one another, refine approaches to science and practice, and develop an implementation research agenda using common measures, methods, and research principles to improve both the frequency and quality with which behavioral health treatment implementation is evaluated. SIRCâs membership growth is a testament to this identified need with more than 1000 members from 2011 to the present.ii SIRCâs primary objectives are to: (1) foster communication and collaboration across diverse groups, including implementation researchers, intermediariesi, as well as community stakeholders (SIRC uses the term âEBP championsâ for these groups) â and to do so across multiple career levels (e.g., students, early career faculty, established investigators); and (2) enhance and disseminate rigorous measures and methodologies for implementing EBPs and evaluating EBP implementation efforts. These objectives are well aligned with Glasgow and colleaguesâ [4] five core tenets deemed critical for advancing implementation science: collaboration, efficiency and speed, rigor and relevance, improved capacity, and cumulative knowledge. SIRC advances these objectives and tenets through in-person conferences, which bring together multidisciplinary implementation researchers and those implementing evidence-based behavioral health interventions in the community to share their work and create professional connections and collaborations
Stimulated echo double diffusion encoded imaging of closed pores: Influence and removal of unbalanced terms
Distributing insecticide-treated bednets during measles vaccination: a low-cost means of achieving high and equitable coverage.
OBJECTIVE: To achieve high and equitable coverage of insecticide-treated bednets by integrating their distribution into a measles vaccination campaign. METHODS: In December 2002 in the Lawra district in Ghana, a measles vaccination campaign lasting 1 week targeted all children aged 9 months-15 years. Families with one or more children less than five years old were targeted to receive a free insecticide-treated bednet. The Ghana Health Service, with support from the Ghana Red Cross and UNICEF, provided logistical support, volunteer workers and social mobilization during the campaign. Volunteers visited homes to inform caregivers about the campaign and encourage them to participate. We assessed pre-campaign coverage of bednets by interviewing caregivers leaving vaccination and distribution sites. Five months after distribution, a two-stage cluster survey using population-proportional sampling assessed bednet coverage, retention and use. Both the pre-campaign and post-campaign survey assessed household wealth using an asset inventory. FINDINGS: At the campaign exit interview 636/776 (82.0%) caregivers reported that they had received a home visit by a Red Cross volunteer before the campaign and that 32/776 (4.1%) of the youngest children in each household who were less than 5 years of age slept under an insecticide-treated bednet. Five months after distribution caregivers reported that 204/219 (93.2%) of children aged 9 months to 5 years had been vaccinated during the campaign; 234/248 (94.4%) of households were observed to have an insecticide-treated bednet; and 170/249 (68.3%) were observed to have a net hung over a bed. Altogether 222/248 (89.5%) caregivers reported receiving at least one insecticide-treated bednet during the campaign, and 153/254 (60.2%) said that on the previous night their youngest child had slept under a bednet received during the campaign. For households in the poorest quintile, post-campaign coverage of insecticide-treated bednets was 10 times higher than pre-campaign coverage of households in the wealthiest quintile (46/51 (90.2%) versus 14/156 (9.0%)). The marginal operational cost was 0.32 US dollars per insecticide-treated bednet delivered. CONCLUSION: These findings suggest that linking bednet distribution to measles vaccination campaigns may provide an important opportunity for achieving high and equitable coverage of bednets
Managing Mortgage Interest-Rate Risks in Forward, Futures, and Options Markets
This article reviews the Housing Commission's perspective and recommendations on management of interest-rate risks in housing finance, and considers the relative advantages of various techniques by which institutions on the supply side of mortgage markets can absorb or shift such risks. It is argued that exchange-based options can provide a more reliable way than cash forward contracting for originators or purchasers of mortgages to manage commitment-period risk, but that commitment fees charged household borrowers should not fully correspond to premiums for put options "traded" on the exchanges. It also is argued that exchange-based futures can provide a more effective and economical way than asset-liability maturity matching in cash markets for thrift institutions to manage portfolio interest-rate risks; in particular, futures trading can permit these institution to meet the maturity preferences of liquidity-conscious creditors and risk-averse borrowers, to reduce the risk associated with unexpected shifts of the yield curve, and to maintain a higher degree of asset quality. The capacity of futures markets to handle large-scale hedging by mortgage market participants will depend upon heavy participation by highly leveraged speculators who are willing to take long positions without the receipt of substantial risk premiums from hedgers. Copyright American Real Estate and Urban Economics Association.
Nuclear Overhauser Enhancement imaging of glioblastoma at 7 Tesla: region specific correlation with apparent diffusion coefficient and histology.
To explore the correlation between Nuclear Overhauser Enhancement (NOE)-mediated signals and tumor cellularity in glioblastoma utilizing the apparent diffusion coefficient (ADC) and cell density from histologic specimens. NOE is one type of chemical exchange saturation transfer (CEST) that originates from mobile macromolecules such as proteins and might be associated with tumor cellularity via altered protein synthesis in proliferating cells.For 15 patients with newly diagnosed glioblastoma, NOE-mediated CEST-contrast was acquired at 7 Tesla (asymmetric magnetization transfer ratio (MTRasym) at 3.3ppm, B1 = 0.7 ÎŒT). Contrast enhanced T1 (CE-T1), T2 and diffusion-weighted MRI (DWI) were acquired at 3 Tesla and coregistered. The T2 edema and the CE-T1 tumor were segmented. ADC and MTRasym values within both regions of interest were correlated voxelwise yielding the correlation coefficient rSpearman (rSp). In three patients who underwent stereotactic biopsy, cell density of 12 specimens per patient was correlated with corresponding MTRasym and ADC values of the biopsy site.Eight of 15 patients showed a weak or moderate positive correlation of MTRasym and ADC within the T2 edema (0.16â€rSpâ€0.53, p<0.05). Seven correlations were statistically insignificant (p>0.05, n = 4) or yielded rSpâ0 (p<0.05, n = 3). No trend towards a correlation between MTRasym and ADC was found in CE-T1 tumor (-0.31<rSp<0.28, p<0.05, n = 9; p>0.05, n = 6). The biopsy-analysis within CE-T1 tumor revealed a strong positive correlation between tumor cellularity and MTRasym values in two of the three patients (rSppatient3 = 0.69 and rSppatient15 = 0.87, p<0.05), while the correlation of ADC and cellularity was heterogeneous (rSppatient3 = 0.545 (p = 0.067), rSppatient4 = -0.021 (p = 0.948), rSppatient15 = -0.755 (p = 0.005)).NOE-imaging is a new contrast promising insight into pathophysiologic processes in glioblastoma regarding cell density and protein content, setting itself apart from DWI. Future studies might be based on the assumption that NOE-mediated CEST visualizes cellularity more accurately than ADC, especially in the CE-T1 tumor region
Regions of interest (ROI) selection for spectral analysis and MTR<sub>asym</sub> quantification.
<p>Left occipital glioblastoma of a 79 year old patient, CE-T1 (A) and T2-weighted images (B) with color coded ROIs: CE-T1 tumor, isolated CEST HIR within CE-T1 margins, tumor necrosis, PTCH within T2 edema margins, CSF and CLNAWM. CEST contrast based on MTR<sub>asym</sub> (C): Same ROIs illustrated in green for improved visualization. Z-spectrum (D) and asymmetry analysis (E) shown. Analyses of Z-spectra reveals that a decrease of NOE upfield effects at â3.3 ppm causes the hyperintense MTR<sub>asym</sub> contrast in the tumor regions, while no clear APT peak around +3.3 ppm could be identified in any of the analyzed tissues. Even though MTR<sub>asym</sub> shows high intensities both in CSF and isolated CEST HIR within CE-T1 tumor, Z-spectrum analysis reveals that the underlying asymmetry has a different origin: no saturation transfer is apparent in CSF at ±3.3 ppm (D black line) while in tumor regions (D dark green, dark blue and light blue lines) MTR<sub>asym</sub>â=â0 reflects that NOE signals (â3.3 ppm) and saturation transfer effects at the opposite side of the Z-spectrum (+3.3 ppm) are of equal size. Furthermore the width of the Z-spectrum of CSF is decreased due to the longer T2 relaxation time.</p
Boxplots of MTR<sub>Asym</sub> quantification from regions of interest (ROI) analysis over all glioblastoma patients.
<p>Boxplots of mean MTR<sub>Asym</sub> values on CEST contrast over all patients (Nâ=â12). Overall mean MTR<sub>asym</sub> (red stars) and outliers (red crosses) are additionally illustrated. MTR<sub>asym</sub> values in all tumor areas (CE-T1 tumor, isolated CEST HIR in CE-T1 tumor, tumor necrosis) and CSF are significantly higher than in CLNAWM (p<0.001). Average signal intensity in PTCH within T2 edema margins is significantly higher (p<0.001) than in CLNAWM and significantly lower (pâ=â0.015) than in CE-T1 tumor and tumor necrosis (p<0.001). The whiskers of the boxplot for isolated CEST HIR indicate a high variance within this group, which is due to smaller ROI size and the fact that the isolated CEST HIR were visually selected relative to surrounding signal intensity in CE-T1 tumor.</p
Tumor satellite lesion displays hyperintense on NOE mediated CEST.
<p>Tumor satellite of a glioblastoma subcortical temporal right in a 67 year old woman. The satellite presents a clear enhancement on CE-T1 (arrow in A) and barely displays on the T2-weighted image (arrow in B). In contrast, the satellite displays clearly hyperintense on CEST based on MTR<sub>asym</sub> (C) and matches with the area of contrast enhancement on the CE-T1 image (A). Furthermore also CSF in lateral ventricles and cerebral sulci displays hyperintense on MTR<sub>asym</sub>.</p
Qualitative analyses of NOE-mediated CEST contrast on 3D co-registered data.
<p>Peritumoral hyperintensity: Comparison of the extent of the peritumoral hyperintensity on CEST and T2-weighted images (smaller*â=âtotal extent smaller on CEST contrast but exceeding the margins of the T2 edema in one direction). <b>Appearance of isolated high intensity regions (HIR) on MTR<sub>asym</sub></b>: Evaluation if isolated CEST HIR on MTR<sub>asym</sub> displayed in the area of CE-T1 tumor or T2 peritumoral edema (Yâ=âYes, Nâ=âNo). <b>Satellite lesions</b>: Fraction of contrast enhanced satellite lesions identified on CE-T1 images that were also clearly hyperintense on CEST (â
â=âno satellite lesion detected).</p