2,923 research outputs found
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No full textHere is a curious book. Its title-page declares "The Artist's Book of Fables" but its pre-title-page has "Fables, Original and Selected, with a Memoir of the Author." After that title-page, it is identical with "Fables, Original and Selected" as in our copy printed by John Murray in 1833. There is again an AI at the front and an index of engravings and engravers at the back. I found that copy twenty years ago. I had found an inferior copy twenty-two years before that. At that time, I noted Aesopic fables here including "Stone Broth" and "The Mouse and the Oyster."This is a hardbound book (hard cover)James Northcote, R.A
Lymphocyte DNA damage in rats challenged with a single bout of strenuous exercise
No full textExercise induces extensive generation of reactive oxygen species, which are responsible for tissue damage: enzymes inactivation, lipid peroxidation and single strand breaks in DNA. Defense system against free radicals is consisting of enzymes such as superoxide dismutase, catalase, glutathione peroxidase, and numerous non-enzymatic antioxidants. The study was performed to evaluate the effect of a single bout of submaximal running exercise, on the lymphocyte DNA strand breaks and also to test how supplementation with tempol - a membrane-permeable SOD-mimetic (0.2 mmol/kg/day) influences the eventually evoked damage. Male, Wistar rats were challenged with graded 50 min. running on treadmill at intensity up to 75-85% of predicted VO(2)max. The DNA strand breaks in individual lymphocytes were determined by using a gel electrophoretic technique - "comet" assay. We found substantial lymphocyte DNA damage 60 min. after the exercise. Tempol failed to prevent from oxidative damage in rats challenged with exercise. Moreover tempol by itself induced higher DNA damage than the exercise bout
Turbulent entrainment in a shearless mixing layer at the edge of a cloud
No full textThree-dimensional direct numerical simulations which combine the Eulerian description of temperature, vapor content and velocity with a Lagrangian ensemble of cloud water droplets are used to study the turbulent entrainment and subsequent mixing of clear air with a cloudy air filament. The study is conducted in a shearless mixing layer setup which is adjusted to realistic conditions at a cumulus cloud boundary. The magnitude of turbulent velocity fluctuations in- and outside the cloud can be varied independently. We find that the evolution of the cloud water droplet ensemble depends slightly only on the contrast of turbulent velocity fluctuations in- and outside the cloud filament. The buoyancy feedback on the flow via the evaporating droplets causes a transient amplification of all fluctuations before the turbulence eventually decays. We study the evolution of the probability density functions of droplet size as well as of supersaturation, temperature and vorticity at the droplet positions
Pyruvate but not lactate prevents NADH-induced myoglobin oxidation
No full textIn this work, we investigated the influence of NADH on the redox state of myoglobin and the roles of pyruvate and lactate in this process. NADH increased the autoxidation rate of myoglobin. Both a drop in pH and partial deoxygenation markedly stimulated the autoxidation process and the influence of NADH. A correlation between met-Mb formation rate and NADH oxidation rate was always observed. The increased rate of Mb autoxidation caused by NADH was inhibited by catalase and pyruvate but not by l-lactate. The antioxidant activity versus H2O2 of both pyruvate and lactate was evidenced by chemiluminescence experiments. The antioxidant activity of lactate disappeared completely in the presence of myoglobin or apo-myoglobin, whereas it was only reduced for pyruvate. These results could be of interest in preventing autoxidation of myoglobin that can contribute to ischemia-reperfusion injury during infarction or high-intensity exercis
Flyleaf of The Village Politicians, signed by author and publisher R.A. Parsons, and printed by Guardian Ltd.
No full textNewIntroduction. Flyleaf of the The Village Politicans by R.A. Parsons and printed by Guardian Ltd.DA vol. 15 no.
Non-Linear Time Series Analysis of Deep Groundwater Levels: An application to the Veluwe
No full textThe objective of this study is to improve the simulation of deep groundwater levels by time se- ries models with pre-defined impulse response functions. This is attempted by adding a conceptual non-linear root zone model to simulate the recharge series to the model and by testing the use of a separate response function for the percolation zone. Three root zone models are developed based on two different recharge mechanisms: preferential flow, percolation, and a combination of the two. The performance of these models is compared to a linear model that is commonly used in time se- ries models to simulate the recharge. The approach is applied to groundwater level measurements in the Veluwe, a largely forested area in the Netherlands characterized by thick unsaturated zones. The effect of groundwater extractions and land reclamations is added to the model to further im- prove the simulation of the groundwater levels. The models are tested on three observations wells with increasing thickness of the unsaturated zone, varying from 7 m to 29 m to 49 m. The results show that model performance is improved by the implementation of a non-linear root zone model, particularly in simulating the peaks and lows in the groundwater levels. The recharge fluxes simulated by the non-linear models show different patterns that are physically more realistic than those simulated by the linear model. It is shown that different recharge series result in simulated groundwater levels that are very similar. This is a clear example of equifinality and it is recommended to introduce new sources of information to validate the modelled processes (e.g., water content measurements of the percolation zone or actual evaporation data). For the shallow well, the models with a single response function are selected as the best. The largest improvements for the deeper groundwater levels are obtained by the addition of a separate response for the percolation zone. For example, the average deviation from the observed ground- water levels decreased 0.18 m to 0.08 m for the deepest observation well by applying the separate response function. The models with an additional response function were better at simulating the estimated time to peak, the time it takes a recharge pulse to cause a peak in the groundwater levels. The time to peak is introduced in this research as a qualitative indicator to validate the modelled processes. The simulated responses indicate that the groundwater levels respond very quickly to water that leaves the root zone, even though the percolation zone is tens of metres thick. For each of the observations wells it is investigated if adding the effect of groundwater extrac- tions or land reclamations of Flevoland to the models improves the simulation of the groundwater levels. For the shallow well it is concluded that either the effect of land reclamations or groundwater extractions needs to be taken into account. Since these two stresses are correlated, it is concluded that only one of these should be taken into account when no further information is available to con- strain the models. For the medium deep well, the additional stresses did not significantly improve model performance and it is concluded that they do not have to be taken into account for this well. For the deep well, model performance is improved by both stresses. The largest improvements are observed when the effect of groundwater extractions is considered in the model. For implemen- tation of these stresses, the entire simulation period should be used for calibration, or constraints have to be implemented to obtain realistic results.Water ResourcesWater ManagementCivil Engineering and Geoscience
PCC Properties to Support W/C Determination for Durability
No full textThe fresh concrete water-cement ratio (w/c) determination tool is urgently needed for use in the QC/QA process at the job site. Various techniques have been used in the past to determine this parameter. However, many of these techniques can be complicated and time consuming. Furthermore, extensive calibration is often needed to correlate the properties measured by these techniques with w/c. During the course of the present study, the method for the use of the unit weight for the determination of w/c of fresh concrete has been developed and evaluated on both laboratory and field concretes. Additionally, the accuracy of using microwave oven technique for w/c determination reported by previous research was confirmed. Finally, the accuracies of unit weight and microwave oven techniques for the determination of w/c were compared.
The unit weights required for this method have been determined either by using a “zero-air” procedure (ZAP) developed as a part of this study or by using conventional (following AASHTO specifications) methods. The ZAP technique was used to verify the w/c of 58 different laboratory concrete mixes. These verification efforts revealed that the minimum, maximum, standard error, and 95th percentile of the differences (∆w/c) between batched and determined w/c were, respectively, 0.000, 0.042, 0.017, and 0.030. The AASHTO determined unit weight (which also required measurements of the actual air content of concrete) was used to verify the w/c values of an additional set of 57 laboratory mixes. When using the AASHTO unit weights (and air contents) the minimum, maximum, standard error, and 95th percentile of ∆w/c were, respectively, 0.000, 0.075, 0.030, and 0.054. In addition, the AASHTO unit weight method was also used to verify the w/c values of 22 different field mixtures. For this case, the differences (∆w/c) between the design and unit weight-calculated values of w/c were in the range ±0.030 for all but one mixture. Finally, direct comparison of the results from the proposed method with the results obtained from the microwave oven method revealed that the former is faster but slightly less accurate. Specifically, when used on five separate concrete samples, the accuracy of the microwave oven method was 0.010, much smaller than the previously mentioned values of 0.030 (for the ZAP) and 0.054 (for the AASHTO) unit weight methods
Chemicals from renewable biomass: A renaissance in carbohydrate chemistry
No full textThe conversion of sugars, derived from waste polysaccharide biomass, to commodity chemicals by fermentation or catalytic hydrogenation, oxidation or dehydration or combinations thereof are reviewed.Accepted Author ManuscriptBT/Biocatalysi
KONSEP HARKAT DAN MARTABAT PEREMPUAN DALAM BUKU HABIS GELAP TERBITLAH TERANG KARYA R.A KARTINI DAN RELEVANSINYA TERHADAP PENDIDIKAN ISLAM
No full textThe background of this research originated from the admiration of the author of the book Habis Gelap Terbitlah Terang by R.A. Kartini who has an extraordinary spirit in fighting for the dignity of women. Women who are not valued, are not recognized, and do no have the opportunity to develop themselves during the R.A. Kartini, now has freedom. His dignity and recognition are recognized by the community. But along with the development of the era that was so extraordinary. Book Habis Gelap Terbitlah Terang began to be forgotten by the people. This research included qualitative research and the type of research that the authors do is library research. The research approach used is the historical approach. The method of data collection in this study is adjusted to the type of research conducted, namely the research library, then the right data collection method is the collection and documentation method. Data analysis in this study uses content analysis method. Based on the results of research conducted by the author about the concept of the dignity of women in view of R.A. Kartini can be concluded that the concept of the dignity of women in the view of R.A. Kartini has seven concepts: educated women, virtuous women, skilled women, free women who are civilized and educated, men collaborate with women, women who are knowledgeable about religion, and delete the caste system in society. The seven concepts have a close relationship to Islamic education which is focused on the goal of Islamic education, namely facilitates women to develop themselves, both in the realm of individuals, families, social and in work so that we create human being.Latar belakang penelitian ini berawal dari kekaguman penulis pada buku Habis Gelap Terbitlah Terang karya R.A. Kartini yang memiliki semangat luar biasa dalam memperjuangkan harkat dan martabat perempuan. Perempuan yang tidak dihargai, tidak diakui, dan tidak memiliki kesempatan untuk mengembangkan diri pada masa R.A. Kartini, kini telah memiliki kebebasan. Harkat dan martabatnya terakui oleh masyarakat. Namun seiring perkembangan zaman yang begitu luar biasa. Buku Habis Gelap Terbitlah Terang ini mulai terlupakan oleh masyarakat. Penelitian ini termasuk penelitian kualitatif dan jenis penelitian yang penulis lakukan merupakan penelitian kepustakaan (library research). Pendekatan penelitian yang digunakan yaitu pendekatan sejarah (histori). Metode pengumpulan data dalam penelitian ini disesuaikan dengen jenis penelitian yang dilakukan, yaitu library research maka metode pengumpulan data yang tepat adalah metode pengumpulan dan dokumentasi. Analisis data pada penelitian ini menggunakan metode content analysis. Berdasarkan hasil penelitian yang dilakukan oleh penulis tentang konsep harkat dan martabat perempuan dalam pandangan R.A. Kartini dapat disimpulkan bahwa konsep harkat dan martabat perempuan dalam pandangan R.A. Kartini ada tujuh konsep yaitu: perempuan berpendidikan, perempuan berbudi luhur, perempuan berketerampilan, perempuan bebas yang beradab dan terpelajar, laki-laki bekerjasama dengan perempuan, perempuan yang berpengetahuan ilmu agama, serta menghapus sistem kasta di masyarakat. Ketujuh konsep tersebut memiliki hubungan yang erat terhadap pendidikan Islam yang difokuskan pada tujuan pendidikan Islam yaitu memfasilitasi perempuan untuk mengembangkan diri, baik dalam ranah individu, keluarga, sosial dan dalam berkarya sehingga terciptalah insan kamil
A Review of Some Updates in the 13th Edition of “Sears and Zemansky’s University Physics with Modern Physics” (Authors: Hugh D. Young and Roger A. Freedman; contributing author, A. Lewis Ford; 2012)
No full textYoung, H.D.; and Freedman, R.A.; Ford, A.L. (contributing author). 2012. Sears and Zemansky’s University Physics with Modern Physics. 13th ed.Pearson Education, Inc., Addison-Wesley, San Francisco, CA, USA
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