700 research outputs found
Swift, the Book, and the Irish Financial Revolution
Winner, 2010 Donald Murphy Prize for a Distinguished First Book, American Conference on Irish StudiesRenowned as one of the most brilliant satirists ever, Jonathan Swift has long fascinated Hibernophiles beyond the shores of the Emerald Isle. Sean Moore's examination of Swift's writings and the economics behind the distribution of his work elucidates the humorist's crucial role in developing a renewed sense of nationalism among the Irish during the eighteenth century.Taking Swift's Irish satires, such as A Modest Proposal and the Drapier's Letters, as examples of anticolonial discourse, Moore unpacks the author's carefully considered published words and his deliberate drive to liberate the Dublin publishing industry from England's shadow to argue that the writer was doing nothing less than creating a national print media. He points to the actions of Anglo-Irish colonial subjects at the outset of Britain's financial revolution; inspired by Swift's dream of a sovereign Ireland, these men and women harnessed the printing press to disseminate ideas of cultural autonomy and defend the country's economic rights. Doing so, Moore contends, imbued the island with a sense of Irishness that led to a feeling of independence from England and ultimately gave the Irish a surprising degree of financial autonomy. Applying postcolonial, new economic, and book history approaches to eighteenth-century studies, Swift, the Book, and the Irish Financial Revolution effectively links the era's critiques of empire to the financial and legal motives for decolonization. Scholars of colonialism, postcolonialism, Irish studies, Atlantic studies, Swift, and the history of the book will find Moore's eye-opening arguments original and compelling
DNA Packaging: A New Class of Molecular Motors
DNA is packaged into preformed bacteriophage capsids to liquid crystalline density by the action of a portal protein complex. Single molecule packaging studies indicate that this is a new and extremely powerful class of molecular motors
Robust Quantification of Polymerase Chain Reactions Using Global Fitting
BACKGROUND: Quantitative polymerase chain reactions (qPCR) are used to monitor relative changes in very small amounts of DNA. One drawback to qPCR is reproducibility: measuring the same sample multiple times can yield data that is so noisy that important differences can be dismissed. Numerous analytical methods have been employed that can extract the relative template abundance between samples. However, each method is sensitive to baseline assignment and to the unique shape profiles of individual reactions, which gives rise to increased variance stemming from the analytical procedure itself. PRINCIPAL FINDINGS: We developed a simple mathematical model that accurately describes the entire PCR reaction profile using only two reaction variables that depict the maximum capacity of the reaction and feedback inhibition. This model allows quantification that is more accurate than existing methods and takes advantage of the brighter fluorescence signals from later cycles. Because the model describes the entire reaction, the influences of baseline adjustment errors, reaction efficiencies, template abundance, and signal loss per cycle could be formalized. We determined that the common cycle-threshold method of data analysis introduces unnecessary variance because of inappropriate baseline adjustments, a dynamic reaction efficiency, and also a reliance on data with a low signal-to-noise ratio. SIGNIFICANCE: Using our model, fits to raw data can be used to determine template abundance with high precision, even when the data contains baseline and signal loss defects. This improvement reduces the time and cost associated with qPCR and should be applicable in a variety of academic, clinical, and biotechnological settings
FFTs for the 2-Sphere-Improvements and Variations
Earlier work by Driscoll and Healy has produced an efficient algorithm for computing the Fourier transform of band-limited functions on the 2-sphere. In this paper we present a reformulation and variation of the original algorithm which results in a greatly improved inverse transform, and consequent improved convolution algorithm for such functions. All require at most 0(N log2 N) operations where N is the number of sample points. We also address implementation considerations and give heuristics for allowing reliable floating point implementations of a slightly modified algorithm at little cost in either theoretical or actual performance. These claims are supported by extensive numerical experiments from our implementation in C on DEC and Sun workstations. These results give strong indications that the algorithm is both reliable and efficient for a large range of useful problem sizes. The paper concludes with a brief discussion of a few potential appications
Crippling the Essential GTPase Der Causes Dependence on Ribosomal Protein L9
Ribosomal protein L9 is a component of all eubacterial ribosomes, yet deletion strains display only subtle growth defects. Although L9 has been implicated in helping ribosomes maintain translation reading frame and in regulating translation bypass, no portion of the ribosome-bound protein seems capable of contacting either the peptidyltransferase center or the decoding center, so it is a mystery how L9 can influence these important processes. To reveal the physiological roles of L9 that have maintained it in evolution, we identified mutants of Escherichia coli that depend on L9 for fitness. In this report, we describe a class of L9-dependent mutants in the ribosome biogenesis GTPase Der (EngA/YphC). Purified mutant proteins were severely compromised in their GTPase activities, despite the fact that the mutations are not present in GTP hydrolysis sites. Moreover, although L9 and YihI complemented the slow-growth der phenotypes, neither factor could rescue the GTPase activities in vitro. Complementation studies revealed that the N-terminal domain of L9 is necessary and sufficient to improve the fitness of these Der mutants, suggesting that this domain may help stabilize compromised ribosomes that accumulate when Der is defective. Finally, we employed a targeted degradation system to rapidly deplete L9 from a highly compromised der mutant strain and show that the L9-dependent phenotype coincides with a cell division defect
An analysis of the fruit-sucking and fruit-piercing moth complex in citrus orchards in South Africa
Fruit-piercing moths are a sporadic pest of citrus, especially in the Eastern Cape Province of South Africa, where the adults can cause significant damage in outbreak years. However, growers confuse fruit-piercing moths with fruit-sucking moths that do not cause primary damage. In this study we trapped these moths during the 2013–2015 growing seasons. A large number of diverse fruit-feeding moths were collected through weekly sampling in citrus orchards in the Eastern Cape and northern Limpopo provinces. Twenty-three species of fruit-feeding moth were trapped. However, only two were fruit-piercing species, capable of causing primary damage, namely Serrodes partita (Fabricius) (Erebidae) and Eudocima divitiosa (Walker) (Erebidae). Surprisingly S. partita, which has been reported as the main fruit-piercing moth pest of citrus in South Africa, comprised only 6.9 % of trap catches. The categorisation of moths as fruit-piercing or fruit-sucking (causing secondary damage) was confirmed by examining the morphological structures (tearing hooks and erectile barbs) of these moths’ proboscides. This study has shown that in non-outbreak seasons, S. partita comprised only a small percentage of fruit-feeding moths in citrus orchards. However, growers may misidentify the harmless fruit-sucking species as fruit-piercing species, and thus overestimate the density of fruit-piercing moths
Integrating chemical control with sterile insect releases in an integrated pest management programme for Thaumatotibia leucotreta
False codling moth Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) is an important indigenous pest of citrus in southern Africa. Successful control is dependent upon integration of area-wide sterile insect releases and other suppression methods. The aim of this work was to test pyrethroid and organophosphate-based insecticides (tau-fluvalinate and chlorpyrifos) for their residual effect on mortality of released irradiated T. leucotreta male moths. Both of these insecticides were effective in killing irradiated T. leucotreta for 7 days after application on leaves, after which degradation of the active ingredient resulted in a marked reduction in efficacy after 14 days and rendering them harmless. Mortality was found to be similar for irradiated and non-irradiated male T. leucotreta after treatment. Consequently, even though these insecticides might have an effect on moths in the field, ratios of sterile:wild moths should not be altered. Supporting field data from six sites in the Sundays River Valley over a season of sterile insect releases showed the conventional chemical crop protection programme to be as effective as an integrated pest management programme in facilitating effective control of T. leucotreta through sterile insect releases. The study also confirmed that the ratios of sterile:wild male moths in the commercial citrus orchards were not affected by the application of insecticides. These findings confirm the high potential of sterile insect releases for control of T. leucotreta in citrus
Titanium Nitride Films for Ultrasensitive Microresonator Detectors
Titanium nitride (TiNx) films are ideal for use in superconducting
microresonator detectors because: a) the critical temperature varies with
composition (0 < Tc < 5 K); b) the normal-state resistivity is large, \rho_n ~
100 Ohm cm, facilitating efficient photon absorption and providing a large
kinetic inductance and detector responsivity; and c) TiN films are very hard
and mechanically robust. Resonators using reactively sputtered TiN films show
remarkably low loss (Q_i > 10^7) and have noise properties similar to
resonators made using other materials, while the quasiparticle lifetimes are
reasonably long, 10-200 s. TiN microresonators should therefore reach
sensitivities well below 10^-19 WHz^(-1/2).Comment: to be published in AP
A case of recurrent epilepsy-associated rosette-forming glioneuronal tumor with anaplastic transformation in the absence of therapy.
Rosette-forming glioneuronal tumor (RGNT) most commonly occurs adjacent to the fourth ventricle and therefore rarely presents with epilepsy. Recent reports describe RGNT occurrence in other anatomical locations with considerable morphologic and genetic overlap with the epilepsy-associated dysembryoplastic neuroepithelial tumor (DNET). Examples of RGNT or DNET with anaplastic change are rare, and typically occur in the setting of radiation treatment. We present the case of a 5-year-old girl with seizures, who underwent near total resection of a cystic temporal lobe lesion. Pathology showed morphologic and immunohistochemical features of RGNT, albeit with focally overlapping DNET-like patterns. Resections of residual or recurrent tumor were performed 1 year and 5 years after the initial resection, but no adjuvant radiation or chemotherapy was given. Ten years after the initial resection, surveillance imaging identified new and enhancing nodules, leading to another gross total resection. This specimen showed areas similar to the original tumor, but also high-grade foci with oligodendroglial morphology, increased cellularity, palisading necrosis, microvascular proliferation, and up to 13 mitotic figures per 10 high power fields. Ancillary studies the status by sequencing showed wild-type of the isocitrate dehydrogenase 1 (IDH1), IDH2, and human histone 3.3 (H3F3A) genes, and BRAF studies were negative for mutation or rearrangement. Fluorescence in situ hybridization (FISH) showed codeletion of 1p and 19q limited to the high-grade regions. By immunohistochemistry there was loss of nuclear alpha-thalassemia mental retardation syndrome, X-linked (ATRX) expression only in the high-grade region. Next-generation sequencing showed an fibroblast growth factor receptor receptor 1 (FGFR1) kinase domain internal tandem duplication in three resection specimens. ATRX mutation in the high-grade tumor was confirmed by sequencing which showed a frameshift mutation (p.R1427fs), while the apparent 1p/19q-codeletion by FISH was due to loss of chromosome arm 1p and only partial loss of 19q. Exceptional features of this case include the temporal lobe location, 1p/19q loss by FISH without true whole-arm codeletion, and anaplastic transformation associated with ATRX mutation without radiation or chemotherapy
Rapid Depletion of Target Proteins Allows Identification of Coincident Physiological Responses
Targeted protein degradation is a powerful tool that can be used to create unique physiologies depleted of important factors. Current strategies involve modifying a gene of interest such that a degradation peptide is added to an expressed target protein and then conditionally activating proteolysis, either by expressing adapters, unmasking cryptic recognition determinants, or regulating protease affinities using small molecules. For each target, substantial optimization may be required to achieve a practical depletion, in that the target remains present at a normal level prior to induction and is then rapidly depleted to levels low enough to manifest a physiological response. Here, we describe a simplified targeted degradation system that rapidly depletes targets and that can be applied to a wide variety of proteins without optimizing target protease affinities. The depletion of the target is rapid enough that a primary physiological response manifests that is related to the function of the target. Using ribosomal protein Si as an example, we show that the rapid depletion of this essential translation factor invokes concomitant changes to the levels of several mRNAs, even before appreciable cell division has occurred
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