794 resultados para Magic tricks
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Cryoultramicrotomy allows the sectioning of vitrified biological samples. These biological samples are preserved at the atomic level and represent the real structure at the moment of freezing. Cryoultramicrotomy produces ultra-thin cryosections that are investigated in a cryoelectron microscope. The necessity of working during the whole preparation at temperatures less than −140°C results in some difficulties, including the cryosection transfer from the knife-edge to the electron microscropy grid; the grid handling in the cryochamber and the grid transfer into the cryoholder of the electron microscope. Furthermore, ice crystal contamination (from air humidity) can obscure the structures of interest in the sections. It is mainly know-how and experience that will prevent the contamination of ice crystals and the recrystallization of the sections during the manipulations. Here, we describe the tips, tricks, the tools, and methods that help to overcome these burdens and pave the path for successful cryoultramicrotomy.
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PURPOSE: To perform baseline T(2) mapping of the hips of healthy volunteers, focusing on topographic variation, because no detailed study has involved hips. T(2) mapping is a quantitative magnetic resonance imaging (MRI) technique that evaluates cartilage matrix components. MATERIALS AND METHODS: Hips of 12 healthy adults (six men and six women; mean age = 29.5 +/- 4.9 years) were studied with a 3.0-Tesla MRI system. T(2) measurement in the oblique-coronal plane used a multi-spin-echo (MSE) sequence. Femoral cartilage was divided into 12 radial sections; acetabular cartilage was divided into six radial sections, and each section was divided into two layers representing the superficial and deep halves of the cartilage. T(2) of these sections and layers were measured. RESULTS: Femoral cartilage T(2) was the shortest (-20 degrees to 20 degrees and -10 degrees to 10 degrees , superficial and deep layers), with an increase near the magic angle (54.7 degrees ). Acetabular cartilage T(2) in both layers was shorter in the periphery than the other parts, especially at 20 degrees to 30 degrees . There were no significant differences in T(2) between right and left hips or between men and women. CONCLUSION: Topographic variation exists in hip cartilage T(2) in young, healthy adults. These findings should be taken into account when T(2) mapping is applied to patients with degenerative cartilage. J. Magn. Reson. Imaging 2007;26:165-171. (c) 2007 Wiley-Liss, Inc.
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A reproducible, standardized and simple sample preparation methodology is the key to successful two-dimensional gel electrophoresis (2-DE). This chapter describes step-by-step the sample preparation of culture medium from Madin-Darby canine kidney (MDCK) cells. Tips and tricks are given to circumvent possible pitfalls.
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ContentsIs the magic back?Dancing and dragonsMinor focuses on eco educationStudent clubs debate sex edWin streak leads into A&M game SundayLanguages connect culturesHow to find eco-friendly fabrics
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The cultivation of dessert apples has to meet the consumer's increasing demand for high fruit quality and a sustainable mostly residue-free production while ensuring a competitive agricultural productivity. It is therefore of great interest to know the impact of different cultivation methods on the fruit quality and the chemical composition, respectively. Previous studies have demonstrated the feasibility of High Resolution Magic Angle Spinning (HR-MAS) NMR spectroscopy directly performed on apple tissue as analytical tool for metabonomic studies. In this study, HR-MAS NMR spectroscopy is applied to apple tissue to analyze the metabolic profiles of apples grown under 3 different cultivation methods. Golden Delicious apples were grown applying organic (Bio), integrated (IP) and low-input (LI) plant protection strategies. A total of 70 1H HR-MAS NMR spectra were analyzed by means of principle component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). Apples derived from Bio-production could be well separated from the two other cultivation methods applying both, PCA and PLS-DA. Apples obtained from integrated (IP) and low-input (LI) production discriminated when taking the third PLS-component into account. The identified chemical composition and the compounds responsible for the separation, i.e. the PLS-loadings, are discussed. The results are compared with fruit quality parameters assessed by conventional methods. The present study demonstrates the potential of HR-MAS NMR spectroscopy of fruit tissue as analytical tool for finding markers for specific fruit production conditions like the cultivation method.
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This book presents six essays by researchers associated with the Technological University of Dresden’s collaborative research centre, Transzendenz und Gemeinsinn, on the interesting theme of religious deviance in early modern cities. As Gerd Schwerhoff and Alexander Kästner make clear in the introduction, early modern religious deviance is a broad concept, and one difficult to delimit, particularly because most early modern secular crimes—theft, adultery, witchcraft and magic, blasphemy—were also sins. Should such offences fall under the rubric of secular or religious deviance? Historians have traditionally approached these offences as secular (and indeed, they were commonly prosecuted in ‘secular’ courts), but one cannot help but see their religious roots. Moreover, religious deviance also encompassed divergence over confessional practices and doctrinal beliefs among Catholics, Protestants, Anabaptists, Calvinists, and so on. To try and demarcate this broad field, Schwerhoff and Kästner advocate using the ‘labelling approach’, drawn from sociology and previously used in Schwerhoff’s work: that is, behaviour only becomes deviant when contemporaries classified (or labelled) it as such (p. 27).
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As atmospheric emissions of S have declined in the Northern Hemisphere, there has been an expectation of increased pH and alkalinity in streams believed to have been acidified by excess S and N. Many streams and lakes have not recovered. Evidence from East Bear Brook in Maine, USA and modelling with the groundwater acid-base model MAGIC (Cosby et al. 1985a,b) indicate that seasonal and yearly variations in soil PCO2 are adequate to enhance or even reverse acid-base (alkalinity) changes anticipated from modest decreases of SO4 in surface waters. Alkalinity is generated in the soil by exchange of H+ from dissociation of H2CO3, which in turn is derived from the dissolving of soil CO2. The variation in soil PCO2 produces an alkalinity variation of up to 15 mu eq L-1 in stream water. Detecting and relating increases in alkalinity to decreases in stream SO4 are significantly more difficult in the short term because of this effect. For example, modelled alkalinity recovery at Bear Brook due to a decline of 20 mu eq SO4 L-1 in soil solution is compensated by a decline from 0.4 to 0.2% for soil air PCO2. This compensation ability decays over time as base saturation declines. Variable PCO2 has less effect in more acidic soils. Short-term decreases of PCO2 below the long-term average value produce short-term decreases in alkalinity, whereas short-term increases in PCO2 produce shortterm alkalization. Trend analysis for detecting recovery of streams and lakes from acidification after reduced atmospheric emissions will require a longer monitoring period for statistical significance than previously appreciated.
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Once more, agriculture threatened to prevent all progress in multilateral trade rule-making at the Ninth WTO Ministerial Conference in December 2013. But this time, the “magic of Bali” worked. After the clock had been stopped mainly because of the food security file, the ministers adopted a comprehensive package of decisions and declarations mainly in respect of development issues. Five are about agriculture. Decision 38 on Public Stockholding for Food Security Purposes contains a “peace clause” which will now be shielding certain stockpile programmes from subsidy complaints in formal litigation. This article provides contextual background and analyses this decision from a legal perspective. It finds that, at best, Decision 38 provides a starting point for a WTO Work Programme for food security, for review at the Eleventh Ministerial Conference which will probably take place in 2017. At worst, it may unduly widen the limited window for government-financed competition existing under present rules in the WTO Agreement on Agriculture – yet without increasing global food security or even guaranteeing that no subsidy claims will be launched, or entertained, under the WTO dispute settlement mechanism. Hence, the Work Programme should find more coherence between farm support and socio-economic and trade objectives when it comes to stockpiles. This also encompasses a review of the present WTO rules applying to other forms of food reserves and to regional or “virtual” stockpiles. Another “low hanging fruit” would be a decision to exempt food aid purchases from export restrictions.
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High Resolution Magic Angle Spinning (HR-MAS) NMR allows metabolic characterization of biopsies. HR-MAS spectra from tissues of most organs show strong lipid contributions that are overlapping metabolite regions, which hamper metabolite estimation. Metabolite quantification and analysis would benefit from a separation of lipids and small metabolites. Generally, a relaxation filter is used to reduce lipid contributions. However, the strong relaxation filter required to eliminate most of the lipids also reduces the signals for small metabolites. The aim of our study was therefore to investigate different diffusion editing techniques in order to employ diffusion differences for separating lipid and small metabolite contributions in the spectra from different organs for unbiased metabonomic analysis. Thus, 1D and 2D diffusion measurements were performed, and pure lipid spectra that were obtained at strong diffusion weighting (DW) were subtracted from those obtained at low DW, which include both small metabolites and lipids. This subtraction yielded almost lipid free small metabolite spectra from muscle tissue. Further improved separation was obtained by combining a 1D diffusion sequence with a T2-filter, with the subtraction method eliminating residual lipids from the spectra. Similar results obtained for biopsies of different organs suggest that this method is applicable in various tissue types. The elimination of lipids from HR-MAS spectra and the resulting less biased assessment of small metabolites have potential to remove ambiguities in the interpretation of metabonomic results. This is demonstrated in a reproducibility study on biopsies from human muscle.
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The different aspects of magic became an essential ingredient of bucolic universe since the origin of pastoral genre. Within an idealized and utopic frame, magic built a bridge towards transcendence, and balanced the disharmony created by human love emotions within Arcadian microcosm. This concept of magic became infused to Sixteenth century pastoral novel through Neoplatonism and Hermetic tradition. From a narratological point of view, magic episodes became indispensable to complete the philosophical meaning of the works. Lope de Vega, in La Arcadia, published in 1598, fully participated from this tradition, though he will approach the convention from a particular dramatic-like perspective. And it was precisely in pastoral comedias where the Fénix ends up deconstructing bucolic code to remodel it as a mere vestige of the tradition and treat magic as a humorous ingredient.
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1H high resolution magic angle spinning (HR-MAS) NMR spectroscopy was applied in combination with multivariate statistical analyses to study the metabolic response of whole cells to the treatment with a hexacationic ruthenium metallaprism [1]6+ as potential anticancer drug. Human ovarian cancer cells (A2780), the corresponding cisplatin resistant cells (A2780cisR), and human embryonic kidney cells (HEK-293) were each incubated for 24 h and 72 h with [1]6+ and compared to untreated cells. Different responses were obtained depending on the cell type and incubation time. Most pronounced changes were found for lipids, choline containing compounds, glutamate and glutathione, nucleotide sugars, lactate, and some amino acids. Possible contributions of these metabolites to physiologic processes are discussed. The time-dependent metabolic response patterns suggest that A2780 cells on one hand and HEK-293 cells and A2780cisR cells on the other hand may follow different cell death pathways and exist in different temporal stages thereof.
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PURPOSE To gain a deeper understanding of the influence of skeletal muscle fiber orientation on metabolite visibility, magnetization transfer from water, and water proton relaxation rates in (1) H MR spectra. METHODS Non-water-suppressed MR spectroscopy was performed in tibialis anterior muscle (TA) of 10 healthy adults, with the TA oriented either parallel or at the magic angle to the 3T field. Spectra were acquired with metabolite-cycled PRESS, and water inversion from 50 to 2510 ms before excitation. Water proton T2 relaxation was sampled with STEAM with echo times from 12 to 272 ms. RESULTS Apparent concentrations of total creatine (tCr), taurine, and trimethylammonium compounds were reduced by 29% to 67% when TA was parallel to B0 . Both tCr peak areas were strongly correlated to the methylene peak splitting. Magnetization transfer rates from water to tCr CH3 were not significantly different between orientations. Water T1 s were similar between orientations, but T2 s were statistically significantly shorter by 1 ms in the parallel orientation (P = 0.002). CONCLUSION Muscle metabolite visibilities in MR spectroscopy and water T2 times depend substantially on muscle fiber orientation relative to B0 . In contrast, magnetization transfer rates appear to depend on muscle composition, rather than fiber orientation. Magn Reson Med, 2015. © 2015 Wiley Periodicals, Inc.
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This paper deals with the difference between risk and insecurity from an anthropological perspective using a critical New Institutionalist approach. Risk refers to the ability to reduce undesirable outcomes, based on a range of information actors have on possible outcomes; insecurity refers to the lack of this information. With regard to the neo-liberal setting of a resource rich area in Zambia, Central Africa, local actors – men and women – face risk and insecurity in market constellations between rural and urban areas. They attempt to cope with risk using technical means and diversification of livelihood strategies. But as common-pool resources have been transformed from common property institutions to open access, also leading to unpredictability of competitors and partners in “free” markets, actors rely on magic options to reduce insecurity and transform it into risk-assessing strategies as an adaptation to modern times. Keywords: Risk, insecurity, institutional change, neo-liberal market, common pool resources, livelihood strategies, magic, Zambia.
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Chemical investigations of superheavy elements in the gas-phase, i.e. elements with Z≥104Z≥104, allow assessing the influence of relativistic effects on their chemical properties. Furthermore, for some superheavy elements and their compounds quite unique gas-phase chemical properties were predicted. The experimental verification of these properties yields supporting evidence for a firm assignment of the atomic number. Prominent examples are the high volatility observed for HsO4 or the very weak interaction of Cn with gold surfaces. The unique properties of HsO4 were exploited to discover the doubly-magic even–even nucleus 270Hs and the new isotope 271Hs. The combination of kinematic pre-separation and gas-phase chemistry allowed gaining access to a new class of relatively fragile compounds, the carbonyl complexes of elements Sg through Mt. A not yet resolved issue concerns the interaction of Fl with gold surfaces. While competing experiments agree on the fact that Fl is a volatile element, there are discrepancies concerning its adsorption on gold surfaces with respect to its daughter Cn. The elucidation of these and other questions amounts to the fascination that gas-phase chemical investigations exert on current research at the extreme limits of chemistry today.
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Not only are dialysis access creation and maintenance prone to complications, but patients suffering from end-stage renal disease and its comorbidities generally have a high risk of adverse events during their continuous treatment. Preventive strategies are key to avoid harm and to improve the outcome of the treatment of the growing number of patients with chronic kidney failure, especially as doctors and nurses are not always aware of the consequences of unsafe behavior. This publication is intended for health care professionals – nurses as well as doctors – and aims to raise the awareness of patient safety aspects, combining medical education with evidence-based medicine. After a general overview of the topic, an international panel of authors provides a diversified insight into important concepts and technical tricks essential to create and maintain a functional dialysis access. Contributions to Nephrology, Vol. 184