18 research outputs found
'Most women have no character at all': female playwrights and the London Theatre, 1760-1800
The eighteenth century saw a remarkable increase in the number of works written by women, and also the number of women who made a living by writing. For the first time, being a writer was a viable career choice for a woman, and it was possible to support a family by writing, despite the backlash some individual writers, such as Mary Wollstonecraft, faced for their work.
This thesis focuses on the work women did in the eighteenth-century theatre, and how they reconciled the demands of being a professional writer with their society's gender expectations. By analysing a variety of play texts written by different women, I show that they engaged critically with ideas about female virtue, the marriage market, and women's participation in the literary scene, the working world, and national politics. The plays of this period are relatively under-researched, and often do not appear at all in critical studies of eighteenth-century literature. My aim, therefore, is to rectify this situation, and to join other critics in rediscovering this interesting and vital era of female playwriting
Direct Imaging of Plant Metabolites in the Rhizosphere Using Laser Desorption Ionization Ultra-High Resolution Mass Spectrometry
The interplay of rhizosphere components such as root exudates, microbes, and minerals
results in small-scale gradients of organic molecules in the soil around roots. The current
methods for the direct chemical imaging of plant metabolites in the rhizosphere often
lack molecular information or require labeling with fluorescent tags or isotopes. Here,
we present a novel workflow using laser desorption ionization (LDI) combined with
mass spectrometric imaging (MSI) to directly analyze plant metabolites in a complex soil
matrix. Undisturbed samples of the roots and the surrounding soil of Zea mays L. plants
from either field- or laboratory-scale experiments were embedded and cryosectioned to
100 mm thin sections. The target metabolites were detected with a spatial resolution of
25 mm in the root and the surrounding soil based on accurate masses using ultra-high
mass resolution laser desorption ionization Fourier-transform ion cyclotron resonance
mass spectrometry (LDI-FT-ICR-MS). Using this workflow, we could determine the
rhizosphere gradients of a dihexose (e.g., sucrose) and other plant metabolites (e.g.,
coumaric acid, vanillic acid). The molecular gradients for the dihexose showed a
high abundance of this metabolite in the root and a strong depletion of the signal
intensity within 150 mm from the root surface. Analyzing several sections from the same
undisturbed soil sample allowed us to follow molecular gradients along the root axis.
Benefiting from the ultra-high mass resolution, isotopologues of the dihexose could be
readily resolved to enable the detection of stable isotope labels on the compound level.
Overall, the direct molecular imaging via LDI-FT-ICR-MS allows for the first time a nontargeted
or targeted analysis of plant metabolites in undisturbed soil samples, paving
the way to study the turnover of root-derived organic carbon in the rhizosphere with
high chemical and spatial resolution
Comparative treatment outcomes after bilateral extractions of maxillary second molars or first premolars in patients with class II malocclusion: a retrospective study
Background
This retrospective cohort study aimed to compare treatment results between bilateral extraction of upper second molars (M2) and first premolars (P1) in terms of treatment timing, cephalometry, upper third molar alignment and relapse in the long-term.
Methods
Fifty-three consecutively treated Caucasian patients with a brachyfacial pattern, skeletal class I and dental class II requiring extraction in the maxilla due to crowding were retrospectively divided into group I (M2 extracted; Nâ=â31) and II (P1 extracted; Nâ=â22). Fixed appliances were inserted after extraction and after distalisation of the first molars in group I. Post-treatment lateral cephalograms were digitally analysed and compared between groups. Six to sevenâyears later relapse and success of upper third molar alignment were clinically evaluated as well as orthodontic treatment duration, pre-treatment age and gender recorded.
Results
After debonding patients with second molar extraction showed significantly smaller values for the Wits-appraisal, but higher values for index and facial axis. Extracting first premolars caused significantly more retroinclination/âposition of anterior teeth and an increased profile concavity, more relapse and less successful alignment of upper third molars. Orthodontic treatment duration, pre-treatment age and gender were not significantly different between groups.
Conclusions
Bilateral extraction of upper first premolars or second molars may solve dental crowding in skeletal class I dental class II patients with a brachyfacial growth pattern. Upper second molar extraction seems to affect maxillary third molar alignment, long-term stability and dental and soft-tissue cephalometric parameters positively, but no intervention proved to be clearly superior
Differences in labile soil organic matter explain potential denitrification and denitrifying communities in a long-term fertilization experiment
Content and quality of organic matter (OM) may strongly affect the denitrification potential of soils. In particular, the impact of soil OM fractions of differing bioavailability (soluble, particulate, and mineral-associated OM) on denitrification remains unresolved. We determined the potential N2O and N2 as well as CO2 production for samples of a Haplic Chernozem from six treatment plots (control, mineral N and NP, farmyard manure - FYM, and FYM + mineral N or NP) of the Static Fertilization Experiment Bad LauchstĂ€dt (Germany) as related to OM properties and denitrifier gene abundances. Soil OM was analyzed for bulk chemical composition (13C-CPMAS NMR spectroscopy) as well as water-extractable, particulate, and mineral-associated fractions. Soils receiving FYM had more total OM and larger portions of labile fractions such as particulate and water-extractable OM. Incubations were run under anoxic conditions without nitrate limitation for seven days at 25 °C in the dark to determine the denitrification potential (N2O and N2) using the acetylene inhibition technique. Abundances of nirS, nirK, and nosZ (I + II) genes were analyzed before and after incubation. The denitrification potential, defined as the combined amount of N released as N2O + N2 over the experimental period, was larger for plots receiving FYM (25.9â27.2 mg N kgâ1) than pure mineral fertilization (17.1â19.2 mg N kgâ1) or no fertilization (12.6 mg N kgâ1). The CO2 and N2O production were well related and up to three-fold larger for FYM-receiving soils than under pure mineral fertilization. The N2 production differed significantly only between all manured and non-manured soils. Nitrogenous gas emissions related most closely to water-extractable organic carbon (WEOC), which again related well to free particulate OM. The larger contribution of N2 production in soils without FYM application, and thus, with less readily decomposable OM, coincided with decreasing abundances of nirS genes (NO2â reductase) and increasing abundances of genes indicating complete denitrifying organisms (nosZ I) during anoxic conditions. Limited OM sources, thus, favored a microbial community more efficient in resource use. This study suggests that WEOC, representing readily bioavailable OM, is a straightforward indicator of the denitrification potential of soils
Global Ocean Sediment Composition and Burial Flux in the Deep Sea
Quantitative knowledge about the burial of sedimentary components at the seafloor has wide-ranging implications in ocean science, from global climate to continental weathering. The use of 230Th-normalized fluxes reduces uncertainties that many prior studies faced by accounting for the effects of sediment redistribution by bottom currents and minimizing the impact of age model uncertainty. Here we employ a recently compiled global data set of 230Th-normalized fluxes with an updated database of seafloor surface sediment composition to derive atlases of the deep-sea burial flux of calcium carbonate, biogenic opal, total organic carbon (TOC), nonbiogenic material, iron, mercury, and excess barium (Baxs). The spatial patterns of major component burial are mainly consistent with prior work, but the new quantitative estimates allow evaluations of deep-sea budgets. Our integrated deep-sea burial fluxes are 136 Tg C/yr CaCO3, 153 Tg Si/yr opal, 20Tg C/yr TOC, 220 Mg Hg/yr, and 2.6 Tg Baxs/yr. This opal flux is roughly a factor of 2 increase over previous estimates, with important implications for the global Si cycle. Sedimentary Fe fluxes reflect a mixture of sources including lithogenic material, hydrothermal inputs and authigenic phases. The fluxes of some commonly used paleo-productivity proxies (TOC, biogenic opal, and Baxs) are not well-correlated geographically with satellite-based productivity estimates. Our new compilation of sedimentary fluxes provides detailed regional and global information, which will help refine the understanding of sediment preservation
"Liberty joined with Peace and Charity": Elizabeth Inchbald and a womanâs place in the revolution
While the French Revolution was one of the defining events of the eighteenth century, it is conspicuously absent from female-authored plays of the time. By the 1790s, women had been using the drama genre to write insightful commentary on other political issues for some time, but writing about the Revolution was accompanied by particular challenges in the form of censorship and increased concerns about sedition.Elizabeth Inchbaldâs 1792 drama The Massacre represents an exception to the stageâs general reticence on the topic. While the play was not staged and the Revolution never named as explicit inspiration for the plot, Inchbald provides a detailed and moving account of the Revolution. This article analyses her perspective on the role and potential of female morality as a means for political change, focussing on the significance of Inchbaldâs inclusion of Madame Tricastin as a tragic martyr figure who condemns the Revolutionâs descent into violence. It also contextualises the unique place that both the Revolution and this particular play occupy in Inchbaldâs writing career
A Novel Deep Learning Approach for Complete Segmentation of Roots, Soil and Pores in X-ray Tomography Data of Acrylic Resin Embedded Rhizosphere
Direct Imaging of Plant Metabolites in the Rhizosphere Using Laser Desorption Ionization Ultra-High Resolution Mass Spectrometry
The interplay of rhizosphere components such as root exudates, microbes, and minerals
results in small-scale gradients of organic molecules in the soil around roots. The current
methods for the direct chemical imaging of plant metabolites in the rhizosphere often
lack molecular information or require labeling with fluorescent tags or isotopes. Here,
we present a novel workflow using laser desorption ionization (LDI) combined with
mass spectrometric imaging (MSI) to directly analyze plant metabolites in a complex soil
matrix. Undisturbed samples of the roots and the surrounding soil of Zea mays L. plants
from either field- or laboratory-scale experiments were embedded and cryosectioned to
100 mm thin sections. The target metabolites were detected with a spatial resolution of
25 mm in the root and the surrounding soil based on accurate masses using ultra-high
mass resolution laser desorption ionization Fourier-transform ion cyclotron resonance
mass spectrometry (LDI-FT-ICR-MS). Using this workflow, we could determine the
rhizosphere gradients of a dihexose (e.g., sucrose) and other plant metabolites (e.g.,
coumaric acid, vanillic acid). The molecular gradients for the dihexose showed a
high abundance of this metabolite in the root and a strong depletion of the signal
intensity within 150 mm from the root surface. Analyzing several sections from the same
undisturbed soil sample allowed us to follow molecular gradients along the root axis.
Benefiting from the ultra-high mass resolution, isotopologues of the dihexose could be
readily resolved to enable the detection of stable isotope labels on the compound level.
Overall, the direct molecular imaging via LDI-FT-ICR-MS allows for the first time a nontargeted
or targeted analysis of plant metabolites in undisturbed soil samples, paving
the way to study the turnover of root-derived organic carbon in the rhizosphere with
high chemical and spatial resolution
Direct Imaging of Plant Metabolites in the Rhizosphere Using Laser Desorption Ionization Ultra-High Resolution Mass Spectrometry
The interplay of rhizosphere components such as root exudates, microbes, and minerals
results in small-scale gradients of organic molecules in the soil around roots. The current
methods for the direct chemical imaging of plant metabolites in the rhizosphere often
lack molecular information or require labeling with fluorescent tags or isotopes. Here,
we present a novel workflow using laser desorption ionization (LDI) combined with
mass spectrometric imaging (MSI) to directly analyze plant metabolites in a complex soil
matrix. Undisturbed samples of the roots and the surrounding soil of Zea mays L. plants
from either field- or laboratory-scale experiments were embedded and cryosectioned to
100 mm thin sections. The target metabolites were detected with a spatial resolution of
25 mm in the root and the surrounding soil based on accurate masses using ultra-high
mass resolution laser desorption ionization Fourier-transform ion cyclotron resonance
mass spectrometry (LDI-FT-ICR-MS). Using this workflow, we could determine the
rhizosphere gradients of a dihexose (e.g., sucrose) and other plant metabolites (e.g.,
coumaric acid, vanillic acid). The molecular gradients for the dihexose showed a
high abundance of this metabolite in the root and a strong depletion of the signal
intensity within 150 mm from the root surface. Analyzing several sections from the same
undisturbed soil sample allowed us to follow molecular gradients along the root axis.
Benefiting from the ultra-high mass resolution, isotopologues of the dihexose could be
readily resolved to enable the detection of stable isotope labels on the compound level.
Overall, the direct molecular imaging via LDI-FT-ICR-MS allows for the first time a nontargeted
or targeted analysis of plant metabolites in undisturbed soil samples, paving
the way to study the turnover of root-derived organic carbon in the rhizosphere with
high chemical and spatial resolution
Experimental platforms for the investigation of spatiotemporal patterns in the rhizosphere-laboratory and field scale
The numerous feedback loops between roots, microorganisms, soil chemical and physical properties, and environmental variables result in spatial parameter patterns which are highly dynamic in time. In order to improve our understanding of the related rhizosphere processes and their relevance at the soilâplant system scale, experimental platforms are required. Those platforms should enable (1) to relate small scale observations (nm to dm) to system behaviour, (2) the integration of physical, chemical and biological sampling approaches within the same experiment, and (3) sampling at different time points during the life cycle of the system in question. Here we describe what requirements have to be met and to what extent this has been achieved in practice by the experimental platforms which were set up within the framework of DFG priority programme 2089 ââRhizosphere Spatiotemporal Organisationâa key to rhizosphere functionsââ. It is discussed to what extent theoretical considerations could be accommodated, in particular for the comparison across scales, i.e., from laboratory to field scale. The latter scale is of utmost importance to overcome the trade-off between fraction of life cycle covered and the avoidance of unrealistic root length densities