University of Massachusetts Boston

About: University of Massachusetts Boston is a education organization based out in Boston, Massachusetts, United States. It is known for research contribution in the topics: Population & Health care. The organization has 6541 authors who have published 12918 publications receiving 411731 citations. The organization is also known as: UMass Boston.

Pollen dispersal by hummingbirds and butterflies: a comparative study of two lowland tropical plants.

Abstract: Because of the difficulties in measuring the distances to which pollen or seed is dispersed, information on gene flow in plant populations is quite limited (Levin and Kerster, 1974). This is particularly true of plants in complex species-rich tropical communities for which such information is of much value in models of speciation for tropical forest trees (Fedorov, 1966; Ashton, 1969; Bawa, 1974, 1979). To the best of our knowledge there are only four reports of pollen dispersal in tropical plants (Linhart, 1973; Frankie et al., 1976; Linhart and Mendenhall, 1977; see also Linhart and Feinsinger, 1980). Here we report the results of a comparative study of pollen flow for two early successional species in Costa Rica: Malvaviscus arboreus is a hummingbird-pollinated shrub or small tree, with hermaphrodite flowers and Cnidoscolus urens is a monoecious, butterfly-pollinated annual herb. The subject populations of the two species occupied adjacent habitats; M. arboreus was confined to margins and light gaps in the river forest and C. urens was found in a fallow rice field adjoining the river forest. Apart from differences in sexual and pollination systems, habit, and habitat, the two species also differed in population density: C. urens occurred in relatively dense patches, 3.0 x 10-2/m2, whereas the population of M. arboreus was more scattered, 3.11 x 10-3/m2 in our sample. Although our principal objective was to determine the effect of differences in pollinator foraging behavior and plant density on pollen flow, our studies also differ

The Variable Effects of Stress on Alcohol Use from Adolescence to Early Adulthood

Abstract: Despite evidence of a strong association between stress and level of drinking in adolescent populations, the role of stress in accounting for changes in drinking behavior throughout the adolescent ...

Stress and the dynamic genome: Steroids, epigenetics, and the transposome.

Abstract: Stress plays a substantial role in shaping behavior and brain function, often with lasting effects. How these lasting effects occur in the context of a fixed postmitotic neuronal genome has been an enduring question for the field. Synaptic plasticity and neurogenesis have provided some of the answers to this question, and more recently epigenetic mechanisms have come to the fore. The exploration of epigenetic mechanisms recently led us to discover that a single acute stress can regulate the expression of retrotransposons in the rat hippocampus via an epigenetic mechanism. We propose that this response may represent a genomic stress response aimed at maintaining genomic and transcriptional stability in vulnerable brain regions such as the hippocampus. This finding and those of other researchers have made clear that retrotransposons and the genomic plasticity they permit play a significant role in brain function during stress and disease. These observations also raise the possibility that the transposome might have adaptive functions at the level of both evolution and the individual organism.

Early sensory over‐responsivity in toddlers with autism spectrum disorders as a predictor of family impairment and parenting stress

Abstract: Higher rates of sensory over-responsivity (SOR) are observed in individuals across autism spectrum disorders (ASD), and SOR symptoms appear to persist from early childhood throughout the lifespan (see Ben-Sasson et al., 2009). SOR is a form of sensory modulation disorder manifested in intense and prolonged negative responses towards commonplace sounds, sights, tastes, smells, movements and touch leading to negative emotionality, distractibility, heightened stress, and avoidance of such input (e.g., avoiding eating soft textured foods, distress from sound of home appliances) as well as aggressive and defiant behavior (Reynolds & Lane, 2008). Rates of SOR in children with ASD vary from 56% – 79% (e.g., Baranek et al., 2006; Tomchek & Dunn, 2007), with a previously documented rate of 56% (>1 standard deviation (SD) below norms) in the current full sample at the first assessment point when children were 18–33 months of age (Ben-Sasson et al., 2007). SOR in children with ASD has been associated with compromised participation in activities of daily living (Kay, 2001) and social interactions (Hilton, Graver, & LaVesser, 2007) as well as internalizing problems (Pfeiffer, Kinnealey, Reed, & Herzberg, 2005). Consequently caregivers of children with comorbid ASD and SOR are dealing with children who have elevated irritability and who often respond with emotional and behavioral dysregulation. In a previous paper on the present sample, maternal stress was concurrently associated with the child's dysregulation problems, which included the following scales: sensory sensitivities, sleeping problems, eating problems and negative emotionality (Davis & Carter, 2008). In this study we sought to examine whether SOR in toddlers with ASD predicts the course of parenting stress and family life impairment above and beyond diagnostic severity and maternal affective symptoms using a standardized detailed measure of sensory behaviors. At time 1 the majority of children in this sample showed extreme under-responsivity and very few showed sensation seeking/craving symptoms (Ben-Sasson et al., 2007), which also can cause strain in family life. We focused on SOR rather than other types of sensory modulation symptoms (i.e., sensation seeking and sensory under-responsivity) as it (1) involves the most challenging behaviors such as tantrums and resistance during routine and non-routine family activities; and (2) has the least measurement overlap with ASD diagnostic symptoms in the current DSM criteria (American Psychiatric Association, 2000), particularly in regards to sensory under-responsivity. Previous research from this sample indicated stability in SOR over time based on the Infant Toddler Social Emotional Assessment's (ITSEA: Carter & Briggs-Gowan, 2006) 6-item Sensory Sensitivity scale (Green, Ben-Sasson, Soto, & Carter, 2011). Studying the course of family impairment and parenting stress in relation to SOR can elucidate factors that challenge families early on and over time, and may require early intervention. Investigating the impairing nature of SOR in children with ASD is timely given the proposal to include unusual sensory behaviors as a subdomain of stereotyped behaviors in the DSM-V. Prior to examining the role of early SOR symptoms on parenting stress and family impairment we first examined the course of both family impairment and parenting stress among parents raising young children with ASD. Several studies have addressed parenting stress but there has been limited attention to family impairment, or the extent to which a child’s symptoms disrupt routine family activities. Parents of children with ASD experience greater levels of parenting stress, depression, and anxiety than parents raising children with other developmental disabilities (Olson & Hwang, 2001; Seltzer, Kraus, Orsmond, & Vestal, 2001; Weiss, 2002), suggesting that these stress levels are not merely associated with the challenges of raising a child with a disability. Evidence from one-(Herring, Taffe, Tonge, Sweeney, & Einfled, 2006; Lecavalier, Leone, & Wiltz, 2006) and two-year (Peters-Scheffer, Didden, & Korzilius, 2012) follow-ups indicate relative stability in parenting stress in families of individuals with ASD. Several attempts have been made to identify child factors that predict stress in parents of individuals with ASD. Among these identified factors in cross-sectional studies are: the severity of ASD symptoms (Benson & Dewey, 2008; Osborne & Reed, 2009) and in particular, social-communication abnormalities (Hastings & Johnson, 2001; Konstantareas, & Homatidis, 1989; Werner DeGrace, 2004); an uneven intellectual profile (Konstantareas, & Homatidis, 1989); and executive dysfunction (Epstein et al., 2008). Concurrent evidence from this sample at the initial assessment indicated that maternal parenting stress was associated with the child’s dysregulation and social relatedness but not with child cognitive and communication skills (Davis & Carter, 2008). Thus, when predicting changes in parenting stress and family impairment variables, we controlled for child diagnostic and behavioral features. Behavior problems in children with ASD have been consistently linked to lower parental well-being (Bromley et al., 2004; Hastings & Brown, 2002; Konstantareas, & Homatidis, 1989; Lecavalier et al., 2006). Specifically, parenting stress in families raising a child with ASD has been positively correlated with hyperactivity, stereotyped behaviors, self-injurious behaviors, and sensory over-sensitivity (Lecavalier et al., 2006), as well as hyper-irritability (Konstantareas, & Homatidis, 1989). In a comparison of toddlers with ASD and those with developmental delays, initial and follow-up child emotional and behavioral problems contributed significantly more to maternal stress, parental mental health problems, and perceived family dysfunction than type of diagnosis (Herring, Taffe, Tonge, Sweeney, & Einfled, 2006). In a longitudinal study of individuals with ASD and intellectual disability, emotional and behavioral problems accounted for 34% and behavioral inflexibility towards objects added an additional 13.6%, of the variance in maternal stress whereas developmental age and ASD severity were not associated with maternal stress (Peters-Scheffer et al., 2012). Some behavior problems in individuals with ASD are likely associated with sensory symptoms and reflect efforts to avoid or control sensory input. For example, engaging in maladaptive forms of repetitive behaviors such as head banging and biting can function as ways for controlling vestibular or tactile input. It is important to note that not all sensory symptoms result in problem behaviors, and that repetitive behaviors can occur in the absence of SOR. In an epidemiological study of children without ASD, SOR was associated with concurrent family impairment independent of the contribution of DSM psychopathologies and socio-demographic risk (Carter, Ben-Sasson, & Briggs-Gowan, 2012). Among families raising a child with Asperger syndrome (5–12 years old), Epstein et al (2008) found that children's sensory symptoms were strongly associated with maternal parenting stress (r = .56). We were interested in examining the relation between early child SOR symptoms and the course of parenting stress and family impairment as a window into the impact of early emerging sensory symptoms on family climate. In this study, SOR, parenting stress, and family life impairment were measured using parent-report tools. Decreased maternal well-being could influence the parent’s perceptions of her child’s behavior. Maternal depression and anxiety have been associated with greater discrepancies in reporting child psychopathology symptoms compared to other informants (Briggs-Gowan, Carter, & Schwab-Stone, 1996). Including indicators of maternal anxiety and depression symptoms in these trajectory models was important to account for this response bias, which could also impact ratings of family impairment and parenting stress. In addition, evidence from the current sample at time 1 for relations between SOR, child anxiety and externalizing symptoms, cognitive level, social-communication symptoms, and maternal anxiety (Green et al., 2012) supported the inclusion of these parameters as covariates in the current research. This study sought to examine whether early SOR in children with ASD is associated with initial and later rates of change in family life impairment and maternal parenting stress. To better interpret these associations, families of children with and without clinically significant levels of SOR were compared on family impairment, parenting stress and child and parent factors.