We propose an enhanced method to accurately retrieve time-activity curves (TACs) of blood and tissue from dynamic 2-deoxy-2-18Ffluoro-D-glucose (18FFDG) positron emission tomography (PET) cardiac ...images of mice. The method is noninvasive and consists of using a constrained nonnegative matrix factorization algorithm (CNMF) applied to the matrix (A) containing the intensity values of the voxels of the left ventricle (LV) PET image. CNMF factorizes A into nonnegative matrices H and W, respectively, representing the physiological factors (blood and tissue) and their associated weights, by minimizing an extended cost function. We verified our method on 32 C57BL/6 mice, 14 of them with acute myocardial infarction (AMI). With CNMF, we could break down the mouse LV into myocardial and blood pool images. Their corresponding TACs were used in kinetic modeling to readily determine the 18FFDG influx constant (Ki) required to compute the myocardial metabolic rate of glucose. The calculated Ki values using CNMF for the heart of control mice were in good agreement with those published in the literature. Significant differences in Ki values for the heart of control and AMI mice were found using CNMF. The values of the elements of W agreed well with the LV structural changes induced by ligation of the left coronary artery. CNMF was compared with the recently published method based on robust unmixing of dynamic sequences using regions of interest (RUDUR). A clear improvement of signal separation was observed with CNMF compared to the RUDUR method.
In intestinal epithelial cells (IEC), it was reported that the activation of the P2X7 receptor leads to the internalization of the glucose transporter GLUT2, which is accompanied by a reduction of ...IEC capacity to transport glucose. In this study, we used P2rx7
mice to decipher P2X7 functions in intestinal glucose transport and to evaluate the impacts on metabolism. Immunohistochemistry analyses revealed the presence of GLUT2 at the apical domain of P2rx7
jejunum enterocytes. Positron emission tomography and biodistribution studies demonstrated that glucose was more efficiently delivered to the circulation of knockout animals. These findings correlated with increase blood glucose, insulin, triglycerides and cholesterol levels. In fact, P2rx7
mice had increased serum triglyceride and cholesterol levels and displayed glucose intolerance and resistance to insulin. Finally, P2rx7
mice developed a hepatic steatosis characterized by a reduction of Acaca, Acacb, Fasn and Acox1 mRNA expression, as well as for ACC and FAS protein expression. Our study suggests that P2X7 could play a central role in metabolic diseases.
The operating temperature of integrated magnetic components can be critical. Excessively high temperature can significantly modify the properties of components, especially those of magnetic material, ...such as saturation magnetization and magnetic permeability. This article introduces an experimental characterization method using two different sensors. We compare the results obtained from these sensors. Initially, the method is validated using a "meander component, and subsequently, it is applied to planar spiral inductors, both with and without magnetic material.
A fascinating examination of the relationship between civilization and inequality from one of history's greatest minds The first man to erect a fence around a piece of land and declare it his own ...founded civil society—and doomed mankind to millennia of war and famine. The dawn of modern civilization, argues Jean-Jacques Rousseau in this essential treatise on human nature, was also the beginning of inequality. One of the great thinkers of the Enlightenment, Rousseau based his work in compassion for his fellow man. The great crime of despotism, he believed, was the raising of the cruel above the weak. In this landmark text, he spells out the antidote for man's ills: a compassionate revolution to pull up the fences and restore the balance of mankind. This ebook has been professionally proofread to ensure accuracy and readability on all devices.
The paper details the characterization of thin magnetic materials layers, particularly soft materials, with respect to their behaviour in frequency (from 10MHz to 1GHz). The proposed method is ...suitable for any soft but insulating magnetic material; Yttrium Iron Garnet (YIG) is used as an example. The principle is based on a comparison between simulations for different values of the permeability and measurement values versus frequency of planar inductor structures; an experimental validation is proposed as well. Thin magnetic material is first deposited on an alumina substrate using RF sputtering technique; a planar spiral winding of copper is then deposited on the magnetic material by the same technique. The effective permeability versus frequency is obtained by comparing two samples of spiral windings with and without magnetic material. Network analyser measurements on samples of various geometrical dimensions and of different thicknesses are necessary to determine the effective magnetic permeability; we have obtained a relative effective permeability of about 30 for seven turns spiral inductor of a 17μm YIG film.
► A simple and original method is presented for the characterization of soft magnetic layer. ► This is a non-destructive method based on standard equipment. ► The principle is based on a comparison between simulations and measurement. ► An experimental validation is proposed as well.
<!CDATANewcomers to Rousseau's works and those who are familiar with his writings will find something to surprise them both in this wide variety of short pieces from every period of his life.
Among ...the important theoretical writings found here are the Fiction or Allegorical Fragment on Revelation and the Moral Letters, which are among Rousseau's clearest statements about the nature and limits of philosophic reasoning. In the early Idea of a Method for the Composition of a Book, Rousseau lays out in advance his understanding of how to present his ideas to the public. He ponders the possibilities for and consequences of air travel in The New Daedalus. This volume also contains both his first and last autobiographical statements.
Some of these writings show Rousseau's lesser-known playful side. A comic fairy tale, Queen Whimsical, explores the consequences--both serious and ridiculous--for a kingdom when the male heir to the throne, endowed with the frivolous characteristics of his mother, has a sister with all the characteristics of a good monarch. When Rousseau was asked whether a fifty-year old man could write love letters to a young woman without appearing ridiculous, he responded with Letters to Sophie, which attempt to demonstrate that such a man could write as many as four--but not as many as six--letters before he became a laughingstock. In The Banterer, he challenges readers to guess whether the work they are reading was written by an author who is wisely mad or by one who is madly wise. When Rousseau was challenged to write a merry tale, without intrigue, without love, without marriage, and without lewdness, he produced a work considered too daring to be published in France.>
This book is intended as an equivalent to or substitute for that "more reflective reading" which Rousseau considered essential to an understanding of his ideas. It is designed to complement perusal ...of the texts themselves, and the arrangement is such that chapters on each of Rousseau's major writings can be consulted separately or the commentary may be read through in sequence. The author's purpose is not to present a "key" to Rousseau's political philosophy, but rather to explore the works themselves in an effort to reveal Rousseau's "system," from which the reader may then draw his own conclusions.
Originally published in 1976.
ThePrinceton Legacy Libraryuses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These paperback editions preserve the original texts of these important books while presenting them in durable paperback editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.