287 research outputs found
The relationship between successional vascular plant assemblages and associated microbial communities on coal mine spoil heaps
The aim of the study was to investigate the relationships between the vascular plant species and the associated soil microbial properties at various stages of vegetation development on unclaimed hard coal mine spoil heaps in Upper Silesia (south Poland). The spontaneous vegetation, soil chemistry as well as the activity and structure of microbial communities were recorded on this specific habitat. The colliery heaps were divided into four age classes and the plant species composition and cover abundance were recorded on established plots (2 m × 2 m). The soil microbial activity under the vegetation patches was assessed using fluorescein diacetate hydrolytic activity (FDHA) and the soil microbial biomass and community composition were determined by phospholipid fatty acid (PLFA) biomarkers. Total microbial biomass in soils from the older vegetation plots was significantly higher than those in soils from the younger plots. In all studied samples, microbial communities consisted primarily of bacteria with the dominance of Gram negative bacteria over Gram positive and aerobic microorganisms were more dominant than anaerobic ones. Statistical analysis revealed a correlation between the type of vegetation and microbial community structure
Vegetation diversity on coal mine spoil heaps-how important is the texture of the soil substrate?
© 2019, The Author(s). The relationship between the size of the particle fractions of the soil substrate and the diversity of the spontaneously developing vegetation was investigated on coal mine spoil heaps in Upper Silesia (Southern Poland). The analyses were based on 2567 research plots of developed spontaneous vegetation and their associated soil substrate samples collected from 112 coal mine spoil heaps. For each research plot the prevailing particle size fraction was determined (stones, gravel, sand, silt), the species composition and abundance was recorded and the species richness (S), Shannon-Wiener diversity index (H′), Simpson (C) and Evenness (E) indices were used to determine species diversity. From a total of 119 research plots (in all particle size fraction categories), the values of 15 physicochemical properties (pH, electrical conductivity, water holding capacity, moisture, carbon content, total N, available P, Mg and exchange cations Ca, Mg, K, Na, fine particles (%), gravel (%), stone (%)) were obtained to asses their impact on the floristic composition of vegetation patches using Canonical Correspondence Analysis (CCA). Additionally, functional traits of the dominant species of each vegetation patch (life forms, life strategies and socio-ecological groups), were selected to analyse their relation to substrate texture. It was shown that the highest species richness and the highest values for Shannon-Wiener diversity index, as well as Simpson and Evenness indices, were obtained in plots formed on stones. Moreover, the greatest variation in the participation of species representing different habitats, life forms, and life strategies was found on gravelly substrates. Contrary to our expectations, the vegetation diversity (in terms of both species and their functional traits) was not highest in habitats with a high composition of fine size particles.Published versio
A Geochemical Record of Late- Holocene Hurricane Events From the Florida Everglades
A 5.25- m sediment core SRM- 1 and 45 surface samples from mangrove forests at the Shark River Estuary in the Everglades National Park, Florida, were examined by using X- ray fluorescence and carbon isotopic analyses to study the history of intense hurricane landfall during the Late- Holocene. Significance testing of the surface samples in relation to storm deposits from Hurricane Wilma suggests that elemental concentration of Sr and Cl and the ratio of Cl/Br are the most sensitive indicators for major hurricane events in our study area. The geochemical data sets of core SRM- 1 identified five active periods of intense hurricane activities during the last 3,500 years at ~3,400- 3,000, ~2,200- 1,500, ~1,000- 800, ~600- 300, and ~150 calibrated years before present to present. This is the longest paleohurricane record to date from South Florida. Our results are consistent with the view that intense hurricane activities in South Florida were modulated by Intertropical Convergence Zone (ITCZ) movements, El Niño/Southern Oscillation (ENSO) activities, and North Atlantic Oscillation (NAO) strength. This study contributes to the methodological advancement in paleotempestological studies by demonstrating that geochemical signals, particularly signals of saltwater intrusions, can be preserved in the sediment profiles on millennial time- scale and measured by X- ray fluorescence techniques, thereby enabling more storm records to be produced from otherwise suboptimal sand- limited coastal systems such as the Florida Everglades. More work needs to be done to explore the use of geochemical and stable isotopic analyses in detecting storm signals from sand- limited coastal environments.Plain Language SummaryThis study uses geochemical analyses to detect intense hurricanes that made landfall near the southwest coast of the Florida Everglades from sediment profiles. The geochemical data sets identified five active periods of intense hurricane activities during the last 3,500 years at ~3,400- 3,000, ~2,200- 1,500, ~1,000- 800, ~600- 300, and ~150 years ago. Results from this study agree with previous studies that intense hurricane activities in the western Atlantic Basin were controlled by the position of ITCZ, ENSO activities, and NAO strength.Key PointsThis study demonstrates the use of XRF analysis in detecting major hurricane events in sand- limited coastal systemsFive active hurricane periods were identified at ~3,400- 3,000, ~2,200- 1,500, ~1,000- 800, ~600- 300, and ~150 cal yr BP to presentThis study suggests that intense hurricane activities in the western Atlantic Basin were modulated by ITCZ, ENSO, and NAO activitiesPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156482/2/wrcr24787_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156482/1/wrcr24787.pd
Moderators, Mediators, and Other Predictors of Risperidone Response in Children with Autistic Disorder and Irritability
Objective/Background:
The National Institute of Mental Health (NIMH) Research Units on Pediatric Psychopharmacology
(RUPP) Autism Network found an effect size of d = 1.2 in favor of risperidone on the main outcome measure
in an 8-week double-blind, placebo-controlled trial for irritabilityin autistic disorder. This paper explores
moderators and mediators of this effect.
Method:
Intention-to-treat (ITT) analyses were conducted with suspected moderators and mediators entered
into the regression equations. MacArthur Foundation Network subgroup guidelines were followed in the
evaluation of the results.
Results:
Only baseline severity moderated treatment response: Higher severity showed greater improvement
for risperidone but not for placebo. Weight gain mediated treatment response negatively: Those who gained
more weight improved less with risperidone and more with placebo. Compliance correlated with outcome for
risperidone but not placebo. Higher dose correlated with worse outcome for placebo, but not risperidone. Of
nonspecific predictors, parent education, family income, and low baseline prolactin positively predicted
outcome; anxiety, bipolar symptoms, oppositional-defiant symptoms, stereotypy, and hyperactivity
negatively predicted outcome. Risperidone moderated the effect of change in 5'-nucleotidase, a marker of
zinc status, for which decrease was associated with improvement only with risperidone, not with placebo.
Conclusion:
The benefit–risk ratio of risperidone is better with greater symptom severity. Risperidone can be
individually titrated to optimal dosage for excellent response in the majority of children. Weight gain is not
necessary for risperidone benefit and may even detract from it. Socioeconomic advantage, low prolactin, and
absence of co-morbid problems non-specifically predict better outcome. Mineral interactions with
risperidone deserve further study
Global-change effects on early-stage decomposition processes in tidal wetlands – implications from a global survey using standardized litter
Tidal wetlands, such as tidal marshes and mangroves, are hotspots for carbon sequestration. The preservation of organic matter (OM) is a critical process by which tidal wetlands exert influence over the global carbon cycle and at the same time gain elevation to keep pace with sea-level rise (SLR). The present study assessed the effects of temperature and relative sea level on the decomposition rate and stabilization of OM in tidal wetlands worldwide, utilizing commercially available standardized litter. While effects on decomposition rate per se were minor, we show strong negative effects of temperature and relative sea level on stabilization, as based on the fraction of labile, rapidly hydrolyzable OM that becomes stabilized during deployment. Across study sites, OM stabilization was 29 % lower in low, more frequently flooded vs. high, less frequently flooded zones. Stabilization declined by ∼ 75 % over the studied temperature gradient from 10.9 to 28.5 ∘C. Additionally, data from the Plum Island long-term ecological research site in Massachusetts, USA, show a pronounced reduction in OM stabilization by > 70 % in response to simulated coastal eutrophication, confirming the potentially high sensitivity of OM stabilization to global change. We therefore provide evidence that rising temperature, accelerated SLR, and coastal eutrophication may decrease the future capacity of tidal wetlands to sequester carbon by affecting the initial transformations of recent OM inputs to soil OM
Author correction : a global database for metacommunity ecology, integrating species, traits, environment and space
Correction to: Scientific Data https://doi.org/10.1038/s41597-019-0344-7, published online 08 January 202
Author correction : a global database for metacommunity ecology, integrating species, traits, environment and space
Correction to: Scientific Data https://doi.org/10.1038/s41597-019-0344-7, published online 08 January 202
DanMAC5:a browser of aggregated sequence variants from 8,671 whole genome sequenced Danish individuals
Registered Replication Report: Rand, Greene, and Nowak (2012)
In an anonymous 4-person economic game, participants contributed more money to a common project (i.e., cooperated) when required to decide quickly than when forced to delay their decision (Rand, Greene & Nowak, 2012), a pattern consistent with the social heuristics hypothesis proposed by Rand and colleagues. The results of studies using time pressure have been mixed, with some replication attempts observing similar patterns (e.g., Rand et al., 2014) and others observing null effects (e.g., Tinghög et al., 2013; Verkoeijen & Bouwmeester, 2014). This Registered Replication Report (RRR) assessed the size and variability of the effect of time pressure on cooperative decisions by combining 21 separate, preregistered replications of the critical conditions from Study 7 of the original article (Rand et al., 2012). The primary planned analysis used data from all participants who were randomly assigned to conditions and who met the protocol inclusion criteria (an intent-to-treat approach that included the 65.9% of participants in the time-pressure condition and 7.5% in the forced-delay condition who did not adhere to the time constraints), and we observed a difference in contributions of −0.37 percentage points compared with an 8.6 percentage point difference calculated from the original data. Analyzing the data as the original article did, including data only for participants who complied with the time constraints, the RRR observed a 10.37 percentage point difference in contributions compared with a 15.31 percentage point difference in the original study. In combination, the results of the intent-to-treat analysis and the compliant-only analysis are consistent with the presence of selection biases and the absence of a causal effect of time pressure on cooperation
Tools and data services registry: a community effort to document bioinformatics resources.
Life sciences are yielding huge data sets that underpin scientific discoveries fundamental to improvement in human health, agriculture and the environment. In support of these discoveries, a plethora of databases and tools are deployed, in technically complex and diverse implementations, across a spectrum of scientific disciplines. The corpus of documentation of these resources is fragmented across the Web, with much redundancy, and has lacked a common standard of information. The outcome is that scientists must often struggle to find, understand, compare and use the best resources for the task at hand.Here we present a community-driven curation effort, supported by ELIXIR-the European infrastructure for biological information-that aspires to a comprehensive and consistent registry of information about bioinformatics resources. The sustainable upkeep of this Tools and Data Services Registry is assured by a curation effort driven by and tailored to local needs, and shared amongst a network of engaged partners.As of November 2015, the registry includes 1785 resources, with depositions from 126 individual registrations including 52 institutional providers and 74 individuals. With community support, the registry can become a standard for dissemination of information about bioinformatics resources: we welcome everyone to join us in this common endeavour. The registry is freely available at https://bio.tools
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