Recent acceleration in coastal cliff retreat rates on the south coast of Great Britain.

Rising sea levels and increased storminess are expected to accelerate the erosion of soft-cliff coastlines, threatening coastal infrastructure and livelihoods. To develop predictive models of future coastal change we need fundamentally to know how rapidly coasts have been eroding in the past, and to understand the driving mechanisms of coastal change. Direct observations of cliff retreat rarely extend beyond 150 y, during which humans have significantly modified the coastal system. Cliff retreat rates are unknown in prior centuries and millennia. In this study, we derived retreat rates of chalk cliffs on the south coast of Great Britain over millennial time scales by coupling high-precision cosmogenic radionuclide geochronology and rigorous numerical modeling. Measured 10Be concentrations on rocky coastal platforms were compared with simulations of coastal evolution using a Monte Carlo approach to determine the most likely history of cliff retreat. The 10Be concentrations are consistent with retreat rates of chalk cliffs that were relatively slow (2-6 cm⋅y-1) until a few hundred years ago. Historical observations reveal that retreat rates have subsequently accelerated by an order of magnitude (22-32 cm⋅y-1). We suggest that acceleration is the result of thinning of cliff-front beaches, exacerbated by regional storminess and anthropogenic modification of the coast.

The effectiveness of beach mega-nourishment, assessed over three management epochs.

Resilient coastal protection requires adaptive management strategies that build with nature to maintain long-term sustainability. With increasing pressures on shorelines from urbanisation, industrial growth, sea-level rise and changing storm climates soft approaches to coastal management are implemented to support natural habitats and maintain healthy coastal ecosystems. The impact of a beach mega-nourishment along a frontage of interactive natural and engineered systems that incorporate soft and hard defences is explored. A coastal evolution model is applied to simulate the impact of different hypothetical mega-nourishment interventions to assess their impacts' over 3 shoreline management planning epochs: present-day (0-20 years), medium-term (20-50 years) and long-term (50-100 years). The impacts of the smaller interventions when appropriately positioned are found to be as effective as larger schemes, thus making them more cost-effective for present-day management. Over time the benefit from larger interventions becomes more noticeable, with multi-location schemes requiring a smaller initial nourishment to achieve at least the same benefit as that of a single-location scheme. While the longer-term impact of larger schemes reduces erosion across a frontage the short-term impact down drift of the scheme can lead to an increase in erosion as the natural sediment drift becomes interrupted. This research presents a transferable modelling tool to assess the impact of nourishment schemes for a variety of sedimentary shorelines and highlights both the positive and negative impact of beach mega-nourishment.

Argonaute of the archaeon Pyrococcus furiosus is a DNA-guided nuclease that targets cognate DNA.

Functions of prokaryotic Argonautes (pAgo) have long remained elusive. Recently, Argonautes of the bacteria Rhodobacter sphaeroides and Thermus thermophilus were demonstrated to be involved in host defense. The Argonaute of the archaeon Pyrococcus furiosus (PfAgo) belongs to a different branch in the phylogenetic tree, which is most closely related to that of RNA interference-mediating eukaryotic Argonautes. Here we describe a functional and mechanistic characterization of PfAgo. Like the bacterial counterparts, archaeal PfAgo contributes to host defense by interfering with the uptake of plasmid DNA. PfAgo utilizes small 5'-phosphorylated DNA guides to cleave both single stranded and double stranded DNA targets, and does not utilize RNA as guide or target. Thus, with respect to function and specificity, the archaeal PfAgo resembles bacterial Argonautes much more than eukaryotic Argonautes. These findings demonstrate that the role of Argonautes is conserved through the bacterial and archaeal domains of life and suggests that eukaryotic Argonautes are derived from DNA-guided DNA-interfering host defense systems.

Geographic distribution of cryptic species of Plasmopara viticola causing downy mildew on wild and cultivated grape in eastern North America.

The putative center of origin of Plasmopara viticola, the causal agent of grape downy mildew, is eastern North America, where it has been described on several members of the family Vitaceae (e.g., Vitis spp., Parthenocissus spp., and Ampelopsis spp.). We have completed the first large-scale sampling of P. viticola isolates across a range of wild and cultivated host species distributed throughout the above region. Sequencing results of four partial genes indicated the presence of a new P. viticola species on Vitis vulpina in Virginia, adding to the four cryptic species of P. viticola recently recorded. The phylogenetic analysis also indicated that the P. viticola species found on Parthenocissus quinquefolia in North America is identical to Plasmopara muralis in Europe. The geographic distribution and host range of five pathogen species was determined through analysis of the internal transcribed spacer polymorphism of 896 isolates of P. viticola. Among three P. viticola species found on cultivated grape, one was restricted to Vitis interspecific hybrids within the northern part of eastern North America. A second species was recovered from V. vinifera and V. labrusca, and was distributed across most of the sampled region. A third species, although less abundant, was distributed across a larger geographical range, including the southern part of eastern North America. P. viticola clade aestivalis predominated (83% of isolates) in vineyards of the European winegrape V. vinifera within the sampled area, indicating that a single pathogen species may represent the primary threat to the European host species within eastern North America.

Fossil proxies of near-shore sea surface temperatures and seasonality from the late Neogene Antarctic shelf.

We evaluate the available palaeontological and geochemical proxy data from bivalves, bryozoans, silicoflagellates, diatoms and cetaceans for sea surface temperature (SST) regimes around the nearshore Antarctic coast during the late Neogene. These fossils can be found in a number of shallow marine sedimentary settings from three regions of the Antarctic continent, the northern Antarctic Peninsula, the Prydz Bay region and the western Ross Sea. Many of the proxies suggest maximum spring-summer SSTs that are warmer than present by up to 5 °C, which would result in reduced seasonal sea ice. The evidence suggests that the summers on the Antarctic shelf during the late Neogene experienced most of the warming, while winter SSTs were little changed from present. Feedbacks from changes in summer sea ice cover may have driven much of the late Neogene ocean warming seen in stratigraphic records. Synthesized late Neogene and earliest Quaternary Antarctic shelf proxy data are compared to the multi-model SST estimates of the Pliocene Model Intercomparison Project (PlioMIP) Experiment 2. Despite the fragmentary geographical and temporal context for the SST data, comparisons between the SST warming in each of the three regions represented in the marine palaeontological record of the Antarctic shelf and the PlioMIP climate simulations show a good concordance.

Super-resolution image reconstruction using diffuse source models.

Image reconstruction is central to many scientific fields, from medical ultrasound and sonar to computed tomography and computer vision. Although lenses play a critical reconstruction role in these fields, digital sensors enable more sophisticated computational approaches. A variety of computational methods have thus been developed, with the common goal of increasing contrast and resolution to extract the greatest possible information from raw data. This paper describes a new image reconstruction method named the Diffuse Time-domain Optimized Near-field Estimator (dTONE). dTONE represents each hypothetical target in the system model as a diffuse region of targets rather than a single discrete target, which more accurately represents the experimental data that arise from signal sources in continuous space, with no additional computational requirements at the time of image reconstruction. Simulation and experimental ultrasound images of animal tissues show that dTONE achieves image resolution and contrast far superior to those of conventional image reconstruction methods. We also demonstrate the increased robustness of the diffuse target model to major sources of image degradation through the addition of electronic noise, phase aberration and magnitude aberration to ultrasound simulations. Using experimental ultrasound data from a tissue-mimicking phantom containing a 3-mm-diameter anechoic cyst, the conventionally reconstructed image has a cystic contrast of -6.3 dB, whereas the dTONE image has a cystic contrast of -14.4 dB.

Diversity and biogeography of sooty blotch and flyspeck fungi on apple in the eastern and midwestern United States.

Sooty blotch and flyspeck (SBFS) fungi on apple fruit were sampled from nine orchards in four midwestern U.S. states during 2000 and 30 orchards in 10 eastern U.S. states during 2005 in order to estimate taxonomic diversity and discern patterns of geographic distribution. Forty apple fruit per orchard were arbitrarily sampled and colonies of each mycelial phenotype were counted on each apple. Representative colonies were isolated, cultures were purified, and DNA was extracted. For representative isolates, the internal transcribed spacer (ITS) and large subunit (LSU) regions of ribosomal DNA were amplified and sequenced. In total, 60 SBFS putative species were identified based on ITS sequences and morphological characteristics; 30 of these were discovered in the 2005 survey. Modified Koch's postulates were fulfilled for all 60 species in an Iowa orchard; colonies resulting from inoculation of apple fruit were matched to the original isolates on the basis of mycelial type and ITS sequence. Parsimony analysis for LSU sequences from both surveys revealed that 58 putative SBFS species were members of the Dothideomycetes, 52 were members of the Capnodiales, and 36 were members of the Mycosphaerellaceae. The number of SBFS species per orchard varied from 2 to 15. Number of SBFS species and values of the Margalef and Shannon indexes were significantly (P < 0.05) lower in 21 orchards that had received conventional fungicide sprays during the fruit maturation period than in 14 unsprayed orchards. Several SBFS species, including Schizothyrium pomi, Peltaster fructicola, and Pseudocercosporella sp. RH1, were nearly ubiquitous, whereas other species, such as Stomiopeltis sp. RS5.2, Phialophora sessilis, and Geastrumia polystigmatis, were found only within restricted geographic regions. The results document that the SBFS complex is far more taxonomically diverse than previously recognized and provide strong evidence that SBFS species differ in geographic distribution. To achieve more efficient management of SBFS, it may be necessary to understand the environmental biology of key SBFS species in each geographic region.

Transformation of Phomopsis viticola with the green fluorescent protein.

Phomopsis viticola is the causal agent of Phomopsis cane and leaf spot on Vitis spp., a persistent and economically important disease in temperate regions. Here we describe the transformation of this fungus with two different constructs (pBHt2_sGFP and pIGPAPA) containing the green fluorescent protein (GFP) and the hygromycin B resistance gene (hph). Protoplast-mediated transformation yielded mitotically stable transformants with no change in virulence on grape internodes and leaves in comparison to the wild type. These transformants will be critical tools for elucidating fungal penetration of host plants, invasive growth and the nature of its host association.

Coping with stressful events: influence of parental alcoholism and race in a community sample of women.

The study explores the role of race and differences in coping among 290 white women and black women with and without alcoholic parents, addressing two questions: (1) Does coping vary by parental alcoholism or race? and (2) How is coping in adulthood affected by childhood stressors and resources and by adulthood resources? Standardized self-administered questionnaires (Coping Responses Inventory and the Children of Alcoholics Screening Test) measuring approach and avoidant coping methods were used. Collateral information was obtained from siblings who completed questionnaires focused on parental drinking, parental psychiatric history, and key childhood events. Women with alcoholic parents and black women more often reported avoidant coping. Women with negative childhood family environments and a lack of adolescent social support more often reported avoidant coping responses. Self-esteem was associated with a higher score on active cognitive coping and a lower score on avoidant coping. Findings of greater use of avoidant coping by women with alcoholic parents contrast with other studies showing no differences in coping, or very small group differences. The fact that all women in this sample lived with two parents in childhood may be one explanation.

Black women and white women: do perceptions of childhood family environment differ?

INTRODUCTION: Few studies have examined racial differences in perceptions of childhood. Little is known about how Blacks perceive their own families, particularly the family environment that they experienced in childhood. METHODS: A community sample of 290 women (55% White, 45% Black) from two-parent families, heterogeneous in age and social class, was examined using a self-administered questionnaire, including the Family Environment Scale (FES), followed by a focused interview. Siblings were used as collateral informants. RESULTS: The psychometric properties of the FES showed remarkably little variation by race: The internal scale reliability, correlations between scales, and factor structures were quite similar. Although both White and Black women reported good childhood family environments, Black women when compared with White women rated their families of origin as more cohesive, organized, and expressive, and lower in conflict. Sibling responses corroborated these findings. DISCUSSION: This study addresses a gap in the research literature and provides important evidence of strengths in Black family relationships as reported by a community sample of women. The psychometric properties of the FES, found to be strong for families of both races, lends support to our findings and those of other researchers who have used this measure.

A spline-based approach for computing spatial impulse responses.

Computer simulations are an essential tool for the design of phased-array ultrasonic imaging systems. FIELD II, which determines the two-way temporal response of a transducer at a point in space, is the current de facto standard for ultrasound simulation tools. However, the need often arises to obtain two-way spatial responses at a single point in time, a set of dimensions for which FIELD II is not well optimized. This paper describes an analytical approach for computing the two-way, far-field, spatial impulse response from rectangular transducer elements under arbitrary excitation. The described approach determines the response as the sum of polynomial functions, making computational implementation quite straightforward. The proposed algorithm, named DELFI, was implemented as a C routine under Matlab and results were compared to those obtained under similar conditions from the well-established FIELD II program. Under the specific conditions tested here, the proposed algorithm was approximately 142 times faster than FIELD II for computing spatial sensitivity functions with similar amounts of error. For temporal sensitivity functions with similar amounts of error, the proposed algorithm was about 1.7 times slower than FIELD II using rectangular elements and 19.2 times faster than FIELD II using triangular elements. DELFI is shown to be an attractive complement to FIELD II, especially when spatial responses are needed at a specific point in time.

Introducing evidence-based practices into substance abuse treatment using organization development methods.

BACKGROUND: Dissemination of evidence-based practices (EBPs) in addiction settings is a national priority. We tested Organization Development (OD) methods for dissemination. METHODS: Using OD in two addiction treatment programs we developed an organization-specific treatment plan using employee work teams with the goals of changes in organizational policies and procedures and improvement in practitioner skills. RESULTS: OD was effectively applied, but EBPs were premature for these addiction programs because they first needed to address more fundamental aspects of client-clinician interaction and agency treatment philosophy. CONCLUSION: The OD approach in addiction treatment is complementary to other technology transfer efforts by being: (a) "organization-centered," engaging practitioners at all levels; (b) "needs-focused," addressing concerns of the particular organization; (c) flexible in its responsiveness to readiness for change; and (d) relatively affordable. However, before absorbing EBPs, substance abuse treatment organizations must develop strengths in delivering fundamental aspects of care.

Racial differences in social support: kin versus friends.

Social support was examined among 290 Black and White women recruited from the community. We hypothesized that (1) social support, adjusted for social class, would not vary by race and (2) social support would be related to well-being. Standardized measures were administered, examining support provided by friends versus kin separately. Multivariate models showed that Black women reported similar numbers of kin and fewer friends than Whites, while satisfaction with support did not vary by race. Measures of social support were generally associated with well-being. These findings question earlier reports that Black women have stronger kin support than White women, suggesting that clinicians should not assume that Blacks can rely on kin for social support.

Childhood sexual abuse among Black women and White women from two-parent families.

Differences in childhood sexual abuse (CSA) between Black women and White women are explored in a community sample of 290 women raised in two-parent families.A self-administered questionnaire and a face-to-face interview assessed CSA characteristics, aftermath, and prevalence as well as family structure and other childhood variables. Siblings served as collateral informants for the occurrence of CSA. Overall, comparisons of the nature, severity, and aftermath of CSA showed similarities by race; some differences, for example, in age of onset, are potentially relevant for the planning of prevention programs. Logistic regression models examined effects of childhood variables on CSA prevalence. Initial analyses showed a higher CSA prevalence among Black women (34.1% [45] of Black women vs. 22.8% [36] of White women) that was attenuated when family structure (e.g., living with two biological parents throughout childhood or not) and social class were considered. Of interest, differences in family structure remained important even among these two-parent families. Understanding the dynamics of abuse by race and family structure will facilitate the design of more targeted CSA prevention programs.

Mediating factors for the long-term effects of parental alcoholism in women: the contribution of other childhood stresses and resources.

The primary aim of this study was to identify the stresses and resources in childhood that mediate the relationship between parental alcoholism and adult outcomes in women. Adult outcomes included alcohol problems and measures of psychosocial adjustment. Standardized measures and a face-to-face interview were used to collect data on 290 community-dwelling women, with siblings as collateral informants. Mediation analysis showed that the effect of parental alcoholism on several adult outcomes was indirect, mediated by the other stresses and resources examined. Contextual models such as those presented here are helpful in understanding the long-term effects of childhood environment on women.

Predicting long-term outcomes for women sexually abused in childhood: contribution of abuse severity versus family environment.

OBJECTIVE: Child sexual abuse (CSA) has been associated with adverse adult psychosocial outcomes, although some reports describe minimal long-term effects. The search for explanations for the heterogeneous outcomes in women with CSA has led to an examination of a range of CSA-related factors, from the severity of individual CSA incidents to the childhood family environment. This study compares three factors for predicting adult outcomes: a multidimensional CSA Severity Scale, the presence or absence of CSA, and family environment. METHODS: The effect of CSA on adult outcomes was examined among 290 community-dwelling women raised in intact families. Standardized measures and a focused interview were used to collect data, with siblings as collateral informants. RESULTS: Comparison of a multidimensional CSA Severity Scale to a dichotomous measure of the presence or absence of CSA showed that the Severity Scale did not have greater predictive value for adult outcomes than the dichotomous measure, nor was it as parsimonious. Childhood family environment scales added significantly to the predictive ability of the dichotomous measure. CONCLUSION: The specific characteristics of a CSA experience may be less important than the occurrence of CSA and the family environment of women for predicting long-term outcomes.