A study describes the development and validation of multiple-item self-report scales to measure opinion leadership and opinion seeking for specific product or service domains. The concepts of opinion ...leadership and opinion seeking are defined, previous attempts to measure them are critiqued, and the scale development process is described. Five separate studies using data from 1,128 student and adult respondents provide ample evidence for the unidimensionality, the reliability, and the construct and criterion-related validity of the resulting scales. Overall, these scales enable marketers to determine the effects of opinion leadership on the adoption of their products. When opinion leaders are important, they can be accurately and easily identified by the scales so that mangers can develop marketing efforts to persuade these influentials to lead other consumers to target brands. Similarly, the opinion seeking scale will allow the assessment of the effects of this variable on the success of marketing strategies.
Deoxyribozymes with 2‘−5‘ RNA Ligase Activity Flynn-Charlebois, Amber; Wang, Yangming; Prior, Tracey K ...
Journal of the American Chemical Society,
03/2003, Letnik:
125, Številka:
9
Journal Article
Recenzirano
In vitro selection was used to identify deoxyribozymes that ligate two RNA substrates. In the ligation reaction, a 2‘−5‘ RNA phosphodiester linkage is created from a 2‘,3‘-cyclic phosphate and a ...5‘-hydroxyl group. The new Mg2+-dependent deoxyribozymes provide 50−60% yield of ligated RNA in overnight incubations at pH 7.5 and 37 °C, and they afford 40−50% yield in 1 h at pH 9.0 and 37 °C. Various RNA substrate sequences may be joined by simple Watson−Crick covaration of the DNA binding arms that interact with the two RNA substrates. The current deoxyribozymes have some RNA substrate sequence requirements at the nucleotides immediately surrounding the ligation junction (either UAUA↓GGAA or UAUN↓GGAA, where the arrow denotes the ligation site and N equals any nucleotide). One of the new deoxyribozymes was used to prepare by ligation the Tetrahymena group I intron RNA P4−P6 domain, a representative structured RNA. Nondenaturing gel electrophoresis revealed that a 2‘−5‘ linkage between nucleotides A233 and G234 of P4−P6 does not disrupt its Mg2+-dependent folding (ΔΔG°‘ < 0.2 kcal/mol). This demonstrates that a 2‘−5‘ linkage does not necessarily interfere with structure in a folded RNA. Therefore, these non-native linkages may be acceptable in modified RNAs when structure/function relationships are investigated. Deoxyribozymes that ligate RNA should be particularly useful for preparing site-specifically modified RNAs for studies of RNA structure, folding, and catalysis.
Air pollution in urban environments has been shown to have a negative impact on air quality and human health, particularly in megacities. Over recent decades, Delhi, India, has suffered high ...atmospheric pollution, with significant particulate matter (PM) concentrations as a result of anthropogenic activities. Organic aerosols (OAs) are composed of thousands of different chemical species and are one of the main constituents of submicron particles. However, quantitative knowledge of OA composition, their sources and their processes in urban environments is still limited. This is important particularly in India, as Delhi is a massive, inhomogeneous conurbation, where we would expect the apportionment and concentrations to vary depending on where in Delhi the measurements/source apportionment is performed, indicating the need for multisite measurements. This study presents the first multisite analysis carried out in India over different seasons, with a focus on identifying OA sources. The measurements were taken during 2018 at two sites in Delhi, India. One site was located at the India Meteorological Department, New Delhi (ND). The other site was located at the Indira Gandhi Delhi Technical University for Women, Old Delhi (OD). Non-refractory submicron aerosol (NR-PM1) concentrations (ammonium, nitrate, sulfate, chloride and organic aerosols) of four aerosol mass spectrometers were analysed. Collocated measurements of volatile organic compounds, black carbon, NOx and CO were performed. Positive matrix factorisation (PMF) analysis was performed to separate the organic fraction, identifying a number of conventional factors: hydrocarbon-like OAs (HOAs) related to traffic emissions, biomass burning OAs (BBOAs), cooking OAs (COAs) and secondary OAs (SOAs).A composition-based estimate of PM1 is defined by combining black carbon (BC) and NR-PM1 (C-PM1= BC + NR-PM1). No significant difference was observed in C-PM1 concentrations between sites, OD (142 ± 117 µg m-3) compared to ND (123 ± 71 µg m3), from post-monsoon measurements. A wider variability was observed between seasons, where pre-monsoon and monsoon showed C-PM1 concentrations lower than 60 µg m-3. A seasonal variation in C-PM1 composition was observed; SO42- showed a high contribution over pre-monsoon and monsoon seasons, while NO3- and Cl- had a higher contribution in winter and post-monsoon. The main primary aerosol source was from traffic, which is consistent with the PMF analysis and Aethalometer model analysis. Thus, in order to reduce PM1 concentrations in Delhi through local emission controls, traffic emission control offers the greatest opportunity. PMF–aerosol mass spectrometer (AMS) mass spectra will help to improve future aerosol source apportionment studies. The information generated in this study increases our understanding of PM1 composition and OA sources in Delhi, India. Furthermore, the scientific findings provide significant information to strengthen legislation that aims to improve air quality in India.
Recent years have seen advances in our understanding of the neural circuits associated with trauma-related disorders, and the development of relevant assays for these behaviors in rodents. Although ...inherited factors are known to influence individual differences in risk for these disorders, it has been difficult to identify specific genes that moderate circuit functions to affect trauma-related behaviors. Here, we exploited robust inbred mouse strain differences in Pavlovian fear extinction to uncover quantitative trait loci (QTL) associated with this trait. We found these strain differences to be resistant to developmental cross-fostering and associated with anatomical variation in basolateral amygdala (BLA) perineuronal nets, which are developmentally implicated in extinction. Next, by profiling extinction-driven BLA expression of QTL-linked genes, we nominated Ppid (peptidylprolyl isomerase D, a member of the tetratricopeptide repeat (TPR) protein family) as an extinction-related candidate gene. We then showed that Ppid was enriched in excitatory and inhibitory BLA neuronal populations, but at lower levels in the extinction-impaired mouse strain. Using a virus-based approach to directly regulate Ppid function, we demonstrated that downregulating BLA-Ppid impaired extinction, while upregulating BLA-Ppid facilitated extinction and altered in vivo neuronal extinction encoding. Next, we showed that Ppid colocalized with the glucocorticoid receptor (GR) in BLA neurons and found that the extinction-facilitating effects of Ppid upregulation were blocked by a GR antagonist. Collectively, our results identify Ppid as a novel gene involved in regulating extinction via functional actions in the BLA, with possible implications for understanding genetic and pathophysiological mechanisms underlying risk for trauma-related disorders.
Background. The study goal was to determine the effect of vitamin D (VITD) supplementation on tubular reabsorption of phosphate (TRP), parathyroid hormone (PTH), bone alkaline phosphatase (BAP), and ...C-telopeptide (CTX) in youth infected with human immunodeficiency virus (HIV) receiving and not receiving combination antiretroviral therapy (cART) containing tenofovir disoproxil fumarate (TDF). Methods. This randomized, double-blind, placebo-controlled multicenter trial enrolled HIV-infected youth 18—25 years based on stable treatment with cART containing TDF (n = 118) or no TDF (noTDF; n = 85), and randomized within those groups to vitamin D3, 50 000 IU (n = 102) or placebo (n = 101), administered at 0, 4, and 8 weeks. Outcomes included change in TRP, PTH, BAP, and CTX from baseline to week 12 by TDF/noTDF; and VITD/placebo. Results. At baseline, VITD and placebo groups were similar except those on TDF had lower TRP and higher PTH and CTX. At week 12, 95% in the VITD group had sufficient serum 25-hydroxy vitamin D (25-OHD; ≥20 ng/mL), increased from 48% at baseline, without change in placebo (P < .001). PTH decreased in the TDF group receiving VITD (P = .031) but not in the noTDF group receiving VITD, or either placebo group. The decrease in PTH with VITD in those on TDF occurred with insufficient and sufficient baseline 25-OHD (mean PTH change, -7.9 and -6.2 pg/mL; P = .031 and .053, respectively). Conclusions. In youth on TDF, vitamin D3 supplementation decreased PTH, regardless of baseline 25-OHD concentration. Clinical Trials Registration. NCT00490412.
Abstract
Introduction
Waking from sleep, especially slow wave sleep (SWS), is associated with reduced alertness known as sleep inertia. Light improves alertness during sleep deprivation and circadian ...misalignment. In this study, we assessed the efficacy of light to improve alertness and mood immediately after waking from SWS.
Methods
Twelve participants kept a sleep schedule of 8.5 h for 5 nights and 5 h for one night prior to the overnight laboratory visit (confirmed by actigraphy). Participants went to bed at their scheduled habitual bedtime in the laboratory and were monitored by standard polysomnography. After at least 5 min of SWS, participants were awoken and exposed to either red ambient light (control) or blue-enriched bright light (light) for 1 h. During this time, participants completed a subjective scale of alertness (Karolinska Sleepiness Scale, KSS) and visual analogue scales (VAS) of mood at 2 min, 17 min, 32 min, and 47 min after waking. Following this sleep inertia measurement period, all lights were turned off and participants were allowed to return to sleep. They were then awoken again from their subsequent SWS period and exposed to the opposite condition (control or light). A linear mixed-effects model with fixed effects of condition, time, and condition*time and a random effect of participant was used to determine the impact of light across the testing period. An average of baseline responses (pre-sleep) was included as a covariate.
Results
Compared to the control condition, participants exposed to blue-enriched bright light reported feeling more alert (KSS: F1,77=4.955, p=.029; VASalert: F1,77=8.226, p=.005), more cheerful (VAScheerful: F1,77=8.615, p=.004), less depressed (VASdepressed: F1,77=4.649, p=.034), and less lethargic (VASlethargic: F1,77=5.652, p=.020).
Conclusion
Exposure to blue-enriched bright light immediately after waking from SWS may help to improve subjective alertness and mood. Future analyses will explore whether these findings extend to effects on cognitive performance.
Support
Naval Postgraduate School Grant. NASA Airspace Operations and Safety Program, System-Wide Safety Project.
There is an emerging interest in on-the-go mapping of apparent soil electrical conductivity (ECa) as a surrogate spatial map for soil properties. The quality (or precision and accuracy) of ECa maps ...as affected by the swath width of the commercial ECa sensing platforms has not been fully explored. For a centre pivot field in Colorado, very dense ECa measurements were collected using a mobile ECa sensor. This fine data layer, representing a base (control) ECa data layer with 2·5
m between the centres of adjacent swaths, was then scaled up to produce coarser ECa data layers with swath widths from 5 to 200
m. The patterns of low, medium and high ECa were produced for all data layers and used to compare different maps. All ECa maps were compared to the base ECa map, and statistical measures of map quality were quantified. Results show a 0·4% and 0·2% reduction in map prediction efficiency and map pattern agreement (as compared to the base map), respectively, per metre increased in swath width. Map quality deteriorated slightly as swath width increased to about 50
m, but at swath widths of 80
m and higher, the quality deteriorated severely and map delineations in the form of location-specific low, medium and high ECa zones became highly distorted and wrongly classified. Increasing the manufacturer's recommended swath width range of 12–18
m to a range of 30–50
m caused only a 10% reduction in map quality while reducing the mapping time by 65%.
Objective:
To investigate and compare babbling, early consonant production and proficiency from 10 to 36 months of age and its relationship with hearing in children with otitis media with effusion ...(OME) with or without cleft palate.
Design:
Prospective, longitudinal group comparison study.
Setting:
University hospital.
Participants:
Fifteen children born with nonsyndromic cleft palate with or without cleft lip (CP±L) and 15 age-matched children with hearing loss (HL) associated with OME but without cleft palate (noncleft group).
Main Outcome Measures:
Canonical babbling (CB) and early consonant variables (presence of oral stops, anterior stops, dental/alveolar stops, number of different true consonants) at 10 and 18 months, and percentage of consonants correct proficiency (PCC) at 36 months.
Results:
A total of 54% of the CP±L group and 77% of the noncleft group had CB. The noncleft group had a significantly higher prevalence of all consonant variables. Percentage of consonants correct was 61.9% in the CP±L group and 81.6% in the noncleft group. All early consonant variables except CB were significantly related to PCC. Hearing sensitivity at 18 and 30 months correlated with PCC and explained 40% of the variation.
Conclusions:
Mild HL impacted presence of CB at 10 months and was related to consonant proficiency at 36 months in children with HL associated with OME and children with cleft palate. The noncleft group showed results at 36 months similar to children with normal hearing; however, the CP±L group did not. Although the cleft palate may have a bigger impact on the speech development, management of hearing sensitivity would also be beneficial.
Intravitreous (i.v.t.) injection is increasingly being incorporated into the management of ocular diseases. While only fomivirsen sodium (Vitravene) is currently approved by the Food and Drug ...Administration as an i.v.t. injection, the number of approved i.v.t. injections indications is anticipated to grow on the basis of promising results from ongoing clinical studies. Despite the potential benefits that may be derived from intraocular injections of different agents, no guidelines have been published previously for i.v.t. injection. The purpose of this document is to identify specific strategies for the delivery of i.v.t. injection that may reduce risks and improve outcomes. Consensus was sought among a panel of investigators, surgeons experienced with this technique, and industry representatives. Objective evidence was sought for all guidelines, but consensus was accepted where evidence remains incomplete. In the absence of either evidence or consensus, the current manuscript identifies outstanding issues in need of further investigation. It is anticipated that more complete guidelines will evolve over time, potentially altering some of the guidelines included here, based on new applications of i.v.t. injection, additional clinical experience, and results of clinical trials.
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