26 research outputs found
Antimicrobial activity of Inga fendleriana extracts and isolated flavonoids.
The EtOAc and n-BuOH extracts of Inga fendleriana inhibited Gram-positive, but not Gram-negative bacteria; a narrow spectrum of activity against Staphylococcus epidermidis was detected. The MIC values of the extracts ranged from 125 to 850 ÎĽg/mL. Quercetin 3-methylether, myricetin 3-O-rhamnoside and tricetin showed antibacterial activity against the same bacterial strains with MICs in the range from 31 to 250 ÎĽg/mL. In time-kill kinetic studies, the flavonoids showed bactericidal effects at the concentrations corresponding to four times the MICs
Success in Graduate School and After: Survey Results from the Midwest Region, Part III
Mechanisms of site-specific dephosphorylation and kinase opposition imposed by PP2A regulatory subunits
Characterizing benthic macroinvertebrate and algal biological condition gradient models for California wadeable Streams, USA
The Biological Condition Gradient (BCG) is a conceptual model that describes changes in aquatic communities under increasing levels of anthropogenic stress. The BCG helps decision-makers connect narrative water quality goals (e.g., maintenance of natural structure and function) to quantitative measures of ecological condition by linking index thresholds based on statistical distributions (e.g., percentiles of reference distributions) to expert descriptions of changes in biological condition along disturbance gradients. As a result, the BCG may be more meaningful to managers and the public than indices alone. To develop a BCG model, biological response to stress is divided into 6 levels of condition, represented as changes in biological structure (abundance and diversity of pollution sensitive versus tolerant taxa) and function. We developed benthic macroinvertebrate (BMI) and algal BCG models for California perennial wadeable streams to support interpretation of percentiles of reference-based thresholds for bioassessment indices (i.e., the California Stream Condition Index [CSCI] for BMI and the Algal Stream Condition Index [ASCI] for diatoms and soft-bodied algae). Two panels (one of BMI ecologists and the other of algal ecologists) each calibrated a general BCG model to California wadeable streams by first assigning taxa to specific tolerance and sensitivity attributes, and then independently assigning test samples (264 BMI and 248 algae samples) to BCG Levels 1–6. Consensus on the assignments was developed within each assemblage panel using a modified Delphi method. Panels then developed detailed narratives of changes in BMI and algal taxa that correspond to the 6 BCG levels. Consensus among experts was high, with 81% and 82% expert agreement within 0.5 units of assigned BCG level for BMIs and algae, respectively. According to both BCG models, the 10th percentiles index scores at reference sites corresponded to a BCG Level 3, suggesting that this type of threshold would protect against moderate changes in structure and function while allowing loss of some sensitive taxa. The BCG provides a framework to interpret changes in aquatic biological condition along a gradient of stress. The resulting relationship between index scores and BCG levels and narratives can help decision-makers select thresholds and communicate how these values protect aquatic life use goals
Environmental, Dietary, Maternal, and Fetal Predictors of Bulky DNA Adducts in Cord Blood: A European Mother–Child Study (NewGeneris)
Background:Bulky DNA adducts reflect genotoxic exposures, have been associated with lower birth weight, and may predict cancer risk.Objective:We selected factors known or hypothesized to affect in utero adduct formation and repair and examined their associations with adduct levels in neonates.Methods:Pregnant women from Greece, Spain, England, Denmark, and Norway were recruited in 2006–2010. Cord blood bulky DNA adduct levels were measured by the 32P-postlabeling technique (n = 511). Diet and maternal characteristics were assessed via questionnaires. Modeled exposures to air pollutants and drinking-water disinfection by-products, mainly trihalomethanes (THMs), were available for a large proportion of the study population.Results:Greek and Spanish neonates had higher adduct levels than the northern European neonates [median, 12.1 (n = 179) vs. 6.8 (n = 332) adducts per 108 nucleotides, p < 0.001]. Residence in southern European countries, higher maternal body mass index, delivery by cesarean section, male infant sex, low maternal intake of fruits rich in vitamin C, high intake of dairy products, and low adherence to healthy diet score were statistically significantly associated with higher adduct levels in adjusted models. Exposure to fine particulate matter and nitrogen dioxide was associated with significantly higher adducts in the Danish subsample only. Overall, the pooled results for THMs in water show no evidence of association with adduct levels; however, there are country-specific differences in results with a suggestion of an association in England.Conclusion:These findings suggest that a combination of factors, including unknown country-specific factors, influence the bulky DNA adduct levels in neonates.Citation:Pedersen M, Mendez MA, Schoket B, Godschalk RW, Espinosa A, Landström A, Villanueva CM, Merlo DF, Fthenou E, Gracia-Lavedan E, van Schooten FJ, Hoek G, Brunborg G, Meltzer HM, Alexander J, Nielsen JK, Sunyer J, Wright J, Kovács K, de Hoogh K, Gutzkow KB, Hardie LJ, Chatzi L, Knudsen LE, Anna L, Ketzel M, Haugen M, Botsivali M, Nieuwenhuijsen MJ, Cirach M, Toledano MB, Smith RB, Fleming S, Agramunt S, Kyrtopoulos SA, Lukács V, Kleinjans JC, Segerbäck D, Kogevinas M. 2015. Environmental, dietary, maternal, and fetal predictors of bulky DNA adducts in cord blood: a European mother–child study (NewGeneris). Environ Health Perspect 123:374–380; http://dx.doi.org/10.1289/ehp.140861
What’S In A Name … Or A Face? Student Perceptions Of Faculty Race
Utilizing Critical Race Theory (CRT) as a conceptual framework, this study examines student perception of faculty of color in academia from student professor preference. Using an experimental design to test the effect of race on selection of faculty with whom to take a course, we showed student participants two types of pairings of faculty: first, pairs of photos of faculty of different races, and same age and attractiveness, then names of faculty, paired by different race were shown. The study provided evidence of racial bias with a strong preference for courses taught by White faculty by various subgroups of students, providing a snapshot of what faculty of color potentially stand to face in classroom environments
The Gender Effect In Student Selection Of Professors For Classes
The purpose of this study is to examine gender preferences that students may have in hypothetical professor selection by either profile picture or catalog listing. First, we showed picture profiles of male and female professors (while controlling for attractiveness and age) to student participants and asked them to select one or the other. Second, we provided students with faculty names indicating their gender in a simulated course catalog format and asked them to select one from the pair. We found that students preferred male faculty overall, both in the photo and name experiment. When we compared male students to female students, male faculty were consistently selected in the name experiment; however in the photo experiment, female students preferred female faculty while male students preferred male faculty. Further, we found evidence of indirect racial effects. Students more often selected male faculty when the photos were White and when the names were White, Black, and Asian. Hispanic faculty pairings were the only ethnic groups where female faculty were preferred over male faculty
The Effects of Item Saliency and Question Design on Measurement Error in a Self-Administered Survey
Recent survey design research has shown that small changes in the structure and visual layout of questions can affect respondents’ answers, but the results are not always consistent across studies. One possible reason for some of the inconsistency may be differences in the item saliency of the questions used in the experiments. In this article, the authors examine how item saliency might influence visual design effects. The authors report the results of three experimental alterations in question format and visual design using data from a 2005 random sample mail survey of 1,315 households. The results suggest that the saliency of the questions has effects both independent of and in concert with the layout of the questions. The implications for survey design are discussed
The Negative Effects of Populism on Gay and Lesbian Rights
The objective of this article is to examine the degree to which populist features of state governments affect minority interests, particularly gays, lesbians, and bisexuals (GLB) Copyright (c) 2009 by the Southwestern Social Science Association.