Bowser's Mathematical Text-Books

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Exchange coupling between two ferromagnetic electrodes separated by a graphene nanoribbon

In this study, based on the self-energy method and the total energy calculation, the indirect exchange coupling between two semi-infinite ferromagnetic strips (FM electrodes) separated by metallic graphene nanoribbons (GNRs) is investigated. In order to form a FM/GNR/FM junction, a graphitic region of finite length is coupled to the FM electrodes along graphitic zigzag or armchair interfaces of width $N$. The numerical results show that, the exchange coupling strength which can be obtained from the difference between the total energies of electrons in the ferromagnetic and antiferromagnetic couplings, has an oscillatory behavior, and depends on the Fermi energy and the length of the central region.Comment: 4 pages, 6 figures, International Conference on Theoretical Physics 'Dubna-Nano2008

Sporopollenin, a natural copolymer, is robust under high hydrostatic pressure

Lycopodium sporopollenin, a natural copolymer, shows exceptional stability under high hydrostatic pressures (10 GPa) as determined by in situ high pressure synchrotron source FTIR spectroscopy. This stability is evaluated in terms of the component compounds of the sporopollenin: p-coumaric acid, phloretic acid, ferulic acid, and palmitic and sebacic acids, which represent the additional n-acid and ndiacid components. This high stability is attributed to interactions between these components, rather than the exceptional stability of any one molecular component. We propose a biomimetic solution for the creation of polymer materials that can withstand high pressures for a multitude of uses in aeronautics, vascular autografts, ballistics and light-weight protective materials

Measurement of Synchrotron x-ray energies and line shapes using diffraction markers

Standard reference markers for accurate, reproducible synchrotron x-ray energies are obtained using a three Si crystal spectrometer. The first two crystals are in the monochromator and the third is used to obtain diffraction markers which monitor the energy. Then for any value of the glancing angle on the reference Si crystal the energy for the (333) diffraction must occur at 3/4 that of the (444) and 3/5 of that for the (555). This establishes for the first time an absolute synchrotron energy scale. Higher-order diffractions are used to determine excitation line profiles. We conclude that the use of reference diffractions is necessary to measure reproducible x-ray energies and to analyze the incident photons\u27 line profile. The detection of diffractions near the edge of measurement and near the Cu edge will provide a fast secondary standard which will allow comparison of edge data between different laboratories. The diffraction profiles will allow the proper analysis of spectral line widths

Life`s certainties: Death, taxes and DC&RM

This is a case history of how one records management and document control team met challenging DOE milestones and successfully addressed a changing culture with respect to document control and records management at a DOE national laboratory (INEL). This account will be of value to persons looking for basic and intermediate level records management information. This paper presents insights into the challenge of document control that will enlighten the inexperienced document control officer to effect real change

War Manifestos

This Article is the first to examine war manifestos, documents that set out the legal reasons sovereigns provided for going to war from the late fifteenth through the mid-twentieth centuries. We have assembled the world\u27s largest collection of war manifestos-over 350-in languages as diverse as Classical Chinese, German, French, Latin, Serbo-Croatian, and Dutch. Prior Anglophone scholarship has almost entirely missed war manifestos. This gap in the literature has produced a correspondingly large gap in our understanding of the role of war during the period in which manifestos were commonly used. Examining these previously ignored manifestos reveals that states exercised the right to wage war in ways that would be inconceivable today. In short, the right to intervene militarily could be asserted in any situation in which a legal right had been violated and all peaceful channels had been explored and exhausted. This Article begins by describing war manifestos. It then explores their history and evolution over the course of five centuries, explains the purposes they served for sovereigns, shows the many \u27just causes they cited for war, and, finally, considers the lessons they hold for modern legal dilemmas. The discovery of war manifestos as a set of legal documents not only offers lawyers and legal scholars a new window into the international legal universe of the past, but it also casts new light on several long-standing legal debates

War Manifestos

This Article is the first to examine “war manifestos,” documents that set out the legal reasons sovereigns provided for going to war from the late fifteenth through the mid-twentieth centuries. We have assembled the world’s largest collection of war manifestos—over 350—in languages as diverse as Classical Chinese, German, French, Latin, Serbo-Croatian, and Dutch. Prior Anglophone scholarship has almost entirely missed war manifestos. This gap in the literature has produced a correspondingly large gap in our understanding of the role of war during the period in which manifestos were commonly used. Examining these previously ignored manifestos reveals that states exercised the right to wage war in ways that would be inconceivable today. In short, the right to intervene militarily could be asserted in any situation in which a legal right had been violated and all peaceful channels had been explored and exhausted. This Article begins by describing war manifestos. It then explores their history and evolution over the course of five centuries, explains the purposes they served for sovereigns, shows the many “just causes” they cited for war, and, finally, considers the lessons they hold for modern legal dilemmas. The discovery of war manifestos as a set of legal documents not only offers lawyers and legal scholars a new window into the international legal universe of the past, but it also casts new light on several long-standing legal debates

Are short-term variations in solar oscillation frequencies the signature of a second solar dynamo?

In addition to the well-known 11-year solar cycle, the Sun's magnetic activity also shows significant variation on shorter time scales, e.g. between one and two years. We observe a quasi-biennial (2-year) signal in the solar p-mode oscillation frequencies, which are sensitive probes of the solar interior. The signal is visible in Sun-as-a-star data observed by different instruments and here we describe the results obtained using BiSON, GOLF, and VIRGO data. Our results imply that the 2-year signal is susceptible to the influence of the main 11-year solar cycle. However, the source of the signal appears to be separate from that of the 11-year cycle. We speculate as to whether it might be the signature of a second dynamo, located in the region of near-surface rotational shear.Comment: 6 pages, 2 figures, proceedings for SOHO-24/GONG 2010 conference, to be published in JPC

Impact of Variant Donor Hepatic Arterial Anatomy on Clinical Graft Outcomes in Liver Transplantation

Standard hepatic arterial anatomy is composed of the common hepatic artery proceeding from the celiac trunk and giving rise to the gastroduodenal artery (GDA) and proper hepatic arteries. Reconstruction of the hepatic arterial supply during liver transplantation, often complex in nature, can be required in cases of accessory or replaced vessels. A recent review summarized the hepatic arterial anatomy reported in over 19,000 cases from 20 individual studies. (1) It has been suggested that the presence of nonstandard donor arterial anatomy may be related to an increased incidence of hepatic artery thrombosis (HAT).(2) Although the overall incidence of HAT is low, it can have devastating effects, including the need for retransplantation, long-term biliary complications, and increased patient mortality. This article describes the arterial anatomy in a large number of liver transplants, with routine anastomosis of a very short hepatic artery and routine reconstruction of the accessory right hepatic artery to the GDA. Study outcomes include incidence of HAT within 30 days of transplant, early graft loss up to 1 year after transplant, and 10-year graft survival

Population, sexual and reproductive health, rights and sustainable development: forging a common agenda.

This article suggests that sexual and reproductive health and rights activists seeking to influence the post-2015 international development paradigm must work with sustainable development advocates concerned with a range of issues, including climate change, environmental issues, and food and water security, and that a way of building bridges with these communities is to demonstrate how sexual and reproductive health and rights are relevant for these issues. An understanding of population dynamics, including urbanization and migration, as well as population growth, can help to clarify these links. This article therefore suggests that whether or not sexual and reproductive health and rights activists can overcome resistance to discussing "population", become more knowledgeable about other sustainable development issues, and work with others in those fields to advance the global sustainable development agenda are crucial questions for the coming months. The article also contends that it is possible to care about population dynamics (including ageing and problems faced by countries with a high proportion of young people) and care about human rights at the same time. It expresses concern that, if sexual and reproductive health and rights advocates do not participate in the population dynamics discourse, the field will be left free for those for whom respecting and protecting rights may be less of a priority