67,237 research outputs found

    Impacts of hunter-gatherers on the vegetation history of the eastern vale of pickering, Yorkshire

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    Research is undertaken into the vegetation and human impact at three previously un-researched archaeological sites from the eastern Vale of Pickering. The vegetation history is reconstructed from the end of the Windermere Interstadial c. 13,000 (^14)C yr BP until the final Mesolithic c. 5100 (^14)C yr BP. The early Mesolithic human impact on the vegetation is assessed using a three stage statistical test to establish the internal variability in the data as well as background variations in pollen output. The results reveal that humans had a small but significant impact on the vegetation around two of the sites. Pollen preservation at the third site precluded analyses of the impacts of humans on the vegetation. The three-stage test used to test for human impact was quite successful but requires revision before any further use. On the whole the tests confirmed the findings of conventional human impact analyses. During the pre-Holocene fires occurred on a regular basis. These fires varied in location and intensity, suggesting that some of the fires were regional or large-scale, whilst others were small and very localized. A multi-causal explanation has been given for the fires. Later, during the early Mesolithic, human groups are thought to have burnt the reedswamp at the lake edges as part of an economic strategy. Star Carr is the only site that demonstrates clearance of significant areas of woodland. During the later Mesolithic the hunter-gatherers have a greater impact on the vegetation within the Vale. This is attributed to the need for more resources as a result of vegetation change and increased population levels. Unlike their counter-parts from the North York Moors, the occupants of the lowland Vale of Pickering cause no long-term change to their environment

    Polypyrimidine tract binding protein and poly r(C) binding protein 1 interact with the BAG-1 IRES and stimulate its activity in vitro and in vivo

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    The 5'-untranslated region of Bag-1 mRNA contains an internal ribosome entry segment (IRES) and the translation of Bag-1 protein can be initiated by both cap-dependent and cap-independent mechanisms. In general, cellular IRESs require non-canonical trans-acting factors for their activity, however, very few of the proteins that act on cellular IRESs have been identified. Proteins that interact with viral IRESs have also been shown to stimulate the activity of cellular IRESs and therefore the ability of a range of known viral trans-acting factors to stimulate the Bag-1 IRES was tested. Two proteins, poly r(C) binding protein 1 (PCBP1) and polypyrimidine tract binding protein (PTB), were found to increase the activity of the Bag-1 IRES in vitro and in vivo. The regions of the Bag-1 IRES RNA to which they bind have been determined, and it was shown that PCBP1 binds to a short 66 nt section of RNA, whilst PTB interacts with a number of sites over a larger area. The minimum section of the RNA that still retained activity was determined and both PCBP1 and PTB interacted with this region suggesting that these proteins are essential for Bag-1 IRES function.<br/

    Describing the participants in a study

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    This paper reviews the use of descriptive statistics to describe the participants included in a study. It discusses the practicalities of incorporating statistics in papers for publication in Age and Aging, concisely and in ways that are easy for readers to understand and interpret

    Gender struggle and the Social Manipulation and Ideological Use of Gender Identity in the Interwar Years

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    The essay analyzes the gender struggle in Italy after WW

    Questions asked and answered in pilot and feasibility randomized controlled trials

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    Abstract Background In the last decade several authors have reviewed the features of pilot and feasibility studies and advised on the issues that should be addressed within them. We extend this literature by examining published pilot/feasibility trials that incorporate random allocation, examining their stated objectives, results presented and conclusions drawn, and comparing drug and non-drug trials. Methods A search of EMBASE and MEDLINE databases for 2000 to 2009 revealed 3652 papers that met our search criteria. A random sample of 50 was selected for detailed review. Results Most of the papers focused on efficacy: those reporting drug trials additionally addressed safety/toxicity; while those reporting non-drug trials additionally addressed methodological issues. In only 56% (95% confidence intervals 41% to 70%) were methodological issues discussed in substantial depth, 18% (95% confidence interval 9% to 30%) discussed future trials and only 12% (95% confidence interval 5% to 24%) of authors were actually conducting one. Conclusions Despite recent advice on topics that can appropriately be described as pilot or feasibility studies the large majority of recently published papers where authors have described their trial as a pilot or addressing feasibility do not primarily address methodological issues preparatory to planning a subsequent study, and this is particularly so for papers reporting drug trials. Many journals remain willing to accept the pilot/feasibility designation for a trial, possibly as an indication of inconclusive results or lack of adequate sample size.</p

    An investigation into the feasibility of comparing three management options (augmentation, conservative and water) for nulliparae with dystocia in the first stage of labour

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    Objective: to evaluate the feasibility of a randomised controlled trial (RCT) examining the effect of three options (augmentation, conservative and water) for the management of dystocia in nulliparae. The main objectives were to explore the feasibility of trial procedures in the clinical environment, consent rates and acceptability of the management options to women, local incidence of dystocia in nulliparae and the size of the subsequent study.Design: a two part study: a pilot, RCT with follow-up through to delivery with postnatal maternal surveys, and a case review of nulliparae with dystocia.Setting: a large maternity unit in the South of England in May–July 1997 inclusive.Participants: nulliparae with dystocia in the first stage of labour who had an otherwise uncomplicated obstetric background.Interventions: women in the pilot RCT received one of three management options: labouring in a waterbirth pool, conservative management or augmentation of labour, which is the standard management of women with dystocia condition in the Unit.Findings: it is feasible to conduct an RCT of management of dystocia in the Unit. Seventy per cent (95% confidence interval 47% to 87%) of women approached agreed to participate. Conservative management was the least acceptable option to women and has been dropped from the subsequent trial. The audit provided some idea of possible differences in operative delivery and epidural rates depending on augmentation or not. A sample of 220 women should be large enough to detect moderate changes and will require a 2-year recruitment period.Conclusions: a subsequent trial is feasible and is now underway. It has the potential to provide information enabling women and practitioners to have a greater choice of care options in the presence of dystocia, or provide a good basis for an even larger trial

    Pickering emulgels reinforced with host-guest supramolecular inclusion complexes for high fidelity direct ink writing

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    | openaire: EC/H2020/788489/EU//BioELCell B. P., S. F. and M. A. gratefully acknowledge the Max Planck Society for financial support. B. P. would like to thank Branislav Jeriga for preparing some of the CNC samples. A. R. and O. R. acknowledge funding support by the Academy of Finland’s Biofuture 2025 program under project 2228357-4 (3D Manufacturing of Novel Biomaterials). O. J. R. is grateful for the support received from the ERC Advanced Grant Agreement No. 788489 (‘‘BioElCell’’), the Canada Excellence Research Chair initiative (CERC-2018-00006), and Canada Foundation for Innovation (Project number 38623). R. A. acknowledges funding from the FinnCERES GoGlobal mobility fund. This work made use of the facilities of Aalto University’s Nanomicroscopy Center. Open Access funding provided by the Max Planck SocietyDirect ink writing (DIW) of Pickering emulsions offers great potential for constructing on-demand objects. However, the rheological properties of fluid emulsions greatly undermines the shape fidelity and structural integrity of 3D-printed structures. We solve here these challenges and realize a new route towards complex constructs for actual deployment. A dynamic, supramolecular host-guest hydrogel based on poly(ethylene glycol) and α-cyclodextrin was synthesized in the continuous phase of cellulose nanocrystal-stabilized Pickering emulsions. The storage modulus of the obtained emulgels could reach up to ∼113 kPa, while being shear thinning and yielding precise printability. Diverse complex architectures were possible with high shape fidelity and structural integrity. The printed objects, for example a double-wall cylinder with 75 layers, demonstrated excellent dimensional stability (shrinkage of 7 ± 2% after freeze-drying). With the merits of a simple fabrication process and the high biocompatibility of all the components, the concept of dynamic supramolecular hydrogel-reinforced emulgels represent a potentially versatile route to construct new materials and structures VIA DIW for use in bioproducts and biomedical devices.Peer reviewe

    Thermal expansion anomalies of R(Fe, M)(12) (R=Y, Nd; M=Mo and Si)

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    Structural and thermal-expansion anomaly studies on R(Fe,M)(12) (R=Nd and and Y, M=Mo and Si) compounds were performed by x-ray diffraction. Mo atoms occupy the 8i site. While Si atoms occupy the 8f and 8j sites but not the 8i site. Thermal-expansion anomaly shows only in ab plane in the Mo compounds, while becomes very weak and along with only the c axis in the Si compounds. The anomaly was attributed to the contribution of the interactions of short Fe-Fe distances similar to the previous explanation on other R-Fe intermetallics and that of other strongly positive interactions such as 8j-8j. (c) 2005 American Institute of Physics.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000230168300025&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Physics, AppliedSCI(E)EICPCI-S(ISTP)

    Sampling power-law distributions

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    Power-law distributions describe many phenomena related to rock fracture. Data collected to measure the parameters of such distributions only represent samples from some underlying population. Without proper consideration of the scale and size limitations of such data, estimates of the population parameters, particularly the exponent D, are likely to be biased. A Monte Carlo simulation of the sampling and analysis process has been made, to test the accuracy of the most common methods of analysis and to quantify the confidence interval for D. The cumulative graph is almost always biased by the scale limitations of the data and can appear non-linear, even when the sample is ideally power law. An iterative correction procedure is outlined which is generally successful in giving unbiased estimates of D. A standard discrete frequency graph has been found to be highly inaccurate, and its use is not recommended. The methods normally used for earthquake magnitudes, such as a discrete frequency graph of logs of values and various maximum likelihood formulations can be used for other types of data, and with care accurate results are possible. Empirical equations are given for the confidence limits on estimates of D, as a function of sample size, the scale range of the data and the method of analysis used. The predictions of the simulations are found to match the results from real sample D-value distributions. The application of the analysis techniques is illustrated with data examples from earthquake and fault population studies
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