bluuebunny/crossref_metadata_2025 huggingface dataset:
Can Ising model and/or QKPZ equation properly describe reactive-wetting interface dynamics?
Authors: Efraim Yael , Taitelbaum Haim
Published: April 2009

The reactive-wetting process, e.g. spreading of a liquid droplet on a reactive substrate is known as a complex, non-linear process with high sensitivity to minor fluctuations. The dynamics and geometry of the interface (triple line) between the materials is supposed to shed light on the main mechanisms of the process. We recently studied a room temperature reactive-wetting system of a small (∼ 150 μm) Hg droplet that spreads on a thin (∼ 4000 Å) Ag substrate. We calculated the kinetic roughening exponents (growth and roughness), as well as the persistence exponent of points on the advancing interface.

In this paper we address the question whether there exists a well-defined model to describe the interface dynamics of this system, by performing two sets of numerical simulations. The first one is a simulation of an interface propagating according to the QKPZ equation, and the second one is a landscape of an Ising chain with ferromagnetic interactions in zero temperature.

We show that none of these models gives a full description of the dynamics of the experimental reactivewetting system, but each one of them has certain common growth properties with it. We conjecture that this results from a microscopic behavior different from the macroscopic one. The microscopic mechanism, reflected by the persistence exponent, resembles the Ising behavior, while in the macroscopic scale, exemplified by the growth exponent, the dynamics looks more like the QKPZ dynamics.
Noise analysis of coaxial Schottky barrier carbon nanotube fets using non equilibrium Green’s function formalism
Authors: Hassaninia Iman , Ghayour Rahim , Abiri Habib , Sheikhi Mohammad
Published: April 2009

The effect of noise on the performance of Schottky Barrier Carbon Nanotube Field Effect Transistors (SB-CNTFETs) has been investigated under various bias conditions. In order to calculate the noise power spectral density, the Non-Equilibrium Green’s Function formalism (NEGF) is used to obtain the transmission coefficient and the number of carriers inside the channel. Results are presented in two sections: In the first section the Hooge’s empirical rule is used to investigate the flicker noise properties of SB-CNTFETs with defects in the gate oxide region, while in the second section the thermal and shot noise properties of SB-CNTFETs are studied. Finally, the best bias points in the ON and OFF states have been suggested according to the total noise power spectral density and the device signal to noise ratio.
The Role of Ecological and Economic Factors in the Management of a Spatially Structured Moose Alces alces Population
Authors: Nilsen Erlend B. , Skonhoft Anders , Mysterud Atle , Milner Jos M. , Solberg Erling J. , Andreassen Harry P. , Stenseth Nils Chr.
Published: April 2009

We present a bioeconomic model for moose Alces alces management in Norway, where two sub‐populations of moose are subject to different site‐specific mortality rates caused by the spatial distribution of territorial wolf Canis lupus packs, and are coupled by the seasonal migration of moose. The costs and benefits of moose are asymmetrically distributed in space, since they congregate in the wolf territory during winter where most browsing damage occurs. Using a class‐structured matrix population model as the basis for bioeconomic analysis, we investigated how the optimal moose management differed between a unified (i.e. maximising overall profit) and a non‐unified (i.e. profit maximised at the level of individual landowners) management scheme. Within the unified management scheme, the combined marginal costs and benefits decide the optimal off‐take rate, and the relative hunting value and damage costs decide the relative allocation of the harvest between the two sub‐populations. In the non‐unified management scheme, harvesting takes place up to the point where the private marginal hunting value equals the private marginal browsing cost, while the relative hunting value and damage costs do not influence the optimal management. As the browsing damage that occurs inside the wolf territory is not taken into account in the costs of the area outside the territory within the non‐unified solution, optimal moose population size will be higher for the outer area than under the unified solution. This results in an overall economic loss, which increases with increasing migration rates. Whenever the boundaries of political or management units do not follow those of ecological processes, ignoring the spatial resolution of the ecological process will result in sub‐optimal management of a renewable resource.
What is the Future for Wild, Large Herbivores in Human‐Modified Agricultural Landscapes?
Authors: Gordon Iain J.
Published: April 2009

Since the dawn of agriculture, people and wild animals have been in conflict because agricultural crops generally offer a rich food source for wild animals as well as for people. Large, wild herbivores compete for pasture resources with livestock and can act as reservoirs of livestock diseases. Furthermore, livestock form a concentrated and vulnerable food source for predators. As a result, humans have extirpated many native animal species from agricultural areas, either directly, or indirectly through modifications in habitat availability or structure resulting from land use changes. As human populations have expanded in developing countries they have caused loss in biodiversity and species extinctions, and will continue to do so. I review attempts to change the interaction between people and large herbivores from one that is primarily negative to one that is positive by increasing the benefits which individuals, communities and society derive from wild, large herbivores. My proposition is that, in developing countries, it is only by using this approach that wild, large herbivores have a chance of surviving outside areas specifically set aside for their protection. In the developed world the opposite trend will occur as people move into the cities causing human populations to decline in rural regions. As a consequence, wildlife habitat will increase and wild, large herbivores will come into conflict with humans, particularly in peri‐urban areas rather than in rural areas as happens at present. This will lead to a change in public attitude from one that supports wildlife conservation to one that sees wild, large herbivores as a threat; again, with potential negative consequences for wildlife conservation.
Evaluating the Sustainability of Harvest Among Northern Common Eiders Somateria Mollissima Borealis in Greenland and Canada
Authors: Gilliland Scott G. , Grant Gilchrist H. , Rockwell Robert F. , Robertson Gregory J. , Savard Jean‐Pierre L. , Merkel Flemming , Mosbech Anders
Published: April 2009

Sustainable harvest, the extraction of game without affecting population viability, is a desirable approach to the use of wildlife. However, overharvest has been responsible for the decline of many wildlife populations globally, so there is an urgent need to balance human requirements while avoiding the severe depletion of wild populations. Northern common eiders Somateria mollissima borealis are heavily hunted in Canada and Greenland, but the effect of this intensive harvest has not been examined. We developed a population model to investigate the sustainability of the reported harvest, which consisted of two wintering areas in Greenland and Atlantic Canada and three breeding populations. The model indicated that harvest in Atlantic Canada was sustainable, but a number of conditions could lead to slow declines. In contrast, the annual winter harvest of 55,000–70,000 eiders reported during 1993–2000 in Greenland was not sustainable, and this conclusion held under a wide range of alternate conditions. The model indicated that harvest during late winter may have a greater effect on populations than harvest in early winter. We further refined the model to assume that at some low population level the success of hunters would decline and that harvest became a function of population size (a rate). This scenario had the expected and undesirable result of stabilizing populations at very low levels. Overall, our model suggests that the high harvest reported in Greenland during 1993–2000 endangers the sustainable use of the northern common eider population and that management actions are required. Common eider harvest levels in Greenland should be reduced by at least 40% of the 1993–2000 levels to stop projected declines, and allow for recovery of the decimated Greenland breeding population. Encouragingly, new hunting regulations were introduced in Greenland in 2002–2004, and harvest levels appear to be decreasing. If these harvest reductions continue, our population model could be used to re‐evaluate the status of populations in the two countries.
Improving Management Plans by Downscaling Hunting Yield Models: A Case Study with the Red‐Legged PartridgeAlectoris rufain Southern Spain
Authors: Farfán Miguel Á. , Vargas Juan M. , Duarte Jesús , Real Raimundo
Published: April 2009

The aim of our work is to predict potentially optimal areas for red‐legged partridgeAlectoris rufahunting success in Andalusia (southern Spain) according to topographic, climatic and vegetation factors and their interaction. We analysed 32,134 annual hunting reports from the period 1993–2001 reported by 6,049 game estates to estimate the average hunting yields of red‐legged partridge in each Andalusian municipality (N= 771). We modelled the favourability for obtaining good hunting yields using generalised linear models (GLM) on a set of climatic, topographic, land use and vegetation variables. The variables that affected hunting yields of red‐legged partridge were dry herbaceous and wood crops, annual number of frost days, altitude and mean annual temperature. Vegetation was the most important factor of those considered in our study explaining the distribution of good hunting yields of the red‐legged partridge in Andalusia. The favourability equation was used to create a downscaled image representing the favourability of obtaining good hunting yields for the red‐legged partridge in 1 × 1‐km squares in Andalusia, using the Idrisi Image Calculator. Downscaling the model from municipalities to 1 × 1‐km squares provided a much higher spatial resolution when predicting the optimal areas for good hunting yields for the red‐legged partridge.
Survival and Reproduction of Pen‐Reared vs Translocated Wild Pheasants Phasianus colchicus
Authors: Musil David D. , Connelly John W.
Published: April 2009

We compared vital rates of two different ring‐necked pheasant Phasianus colchicus stocks (pen‐reared and wild) and assessed effects of predator control on these pheasants released into current range. Wild (31 males and 112 females) and pen‐reared (230 males and 1,059 females) ring‐necked pheasants were released in spring into two areas in southern Idaho during 2000–2001 to augment low resident populations. Wild female survival (value ± 95% CI) from 1 March‐1 October was significantly greater than that of pen‐reared females in both 2000 (0.40 ± 0.14, N = 62 vs 0.04 ± 0.07, N = 49) and 2001 (0.43 ± 0.16, N = 40 vs 0.08 ± 0.10, N = 40). Of 134 documented deaths of radio‐marked female pheasants, 54% were due to unknown predation, 26% to mammalian predators, 12% to avian predators, 4% to natural causes, and 4% were human caused. Wild females had a 0.23 ± 0.09 (N=88) nesting rate and pen‐reared females 0.28 ± 0.18 (N = 25). During 2001, predators were removed within our study areas. Survival of wild male pheasants increased after predator removal (0.20 ± 0.35, N = 6 vs 0.70 ± 0.28, N = 10), but survival did not increase for either stock of female pheasants after predator removal. Predator control did not increase the number of hens surviving to reach the nesting season (1 May), nesting rate or nest success. Wild female pheasants were seven times more likely to survive translocation to 1 October, 10 times more likely to survive to the nesting season, eight times more productive, and one‐third as expensive per egg hatched than pen‐reared females. Low survival, poor productivity and higher costs of spring‐released pen‐reared female pheasants strongly suggest that this is an inappropriate management tool for increasing pheasant numbers.
Hereditary and Sporadic Forms of Aβ-Cerebrovascular Amyloidosis and Relevant Transgenic Mouse Models
Authors: Kumar-Singh Samir
Published: April 2009

Cerebral amyloid angiopathy (CAA) refers to the specific deposition of amyloid fibrils in the leptomeningeal and cerebral blood vessel walls, often causing secondary vascular degenerative changes. Although many kinds of peptides are known to be deposited as vascular amyloid, amyloid-β (Aβ)-CAA is the most common type associated with normal aging, sporadic CAA, Alzheimer’s disease (AD) and Down’s syndrome. Moreover, Aβ-CAA is also associated with rare hereditary cerebrovascular amyloidosis due to mutations within the Aβ domain of the amyloid precursor protein (APP) such as Dutch and Flemish APP mutations. Genetics and clinicopathological studies on these familial diseases as well as sporadic conditions have already shown that CAA not only causes haemorrhagic and ischemic strokes, but also leads to progressive dementia. Transgenic mouse models based on familial AD mutations have also successfully reproduced many of the features found in human disease, providing us with important insights into the pathogenesis of CAA. Importantly, such studies have pointed out that specific vastopic Aβ variants or an unaltered Aβ42/Aβ40 ratio favor vascular Aβ deposition over parenchymal plaques, but higher than critical levels of Aβ40 are also observed to be anti-amyloidogenic. These data would be important in the development of therapies targeting amyloid in vessels.
Marine Antimalarials
Authors: Fattorusso Ernesto , Taglialatela-Scafati Orazio
Published: April 2009

Malaria is an infectious disease causing at least 1 million deaths per year, and, unfortunately, the chemical entities available to treat malaria are still too limited. In this review we highlight the contribution of marine chemistry in the field of antimalarial research by reporting the most important results obtained until the beginning of 2009, with particular emphasis on recent discoveries. About 60 secondary metabolites produced by marine organisms have been grouped into three structural types and discussed in terms of their reported antimalarial activities. The major groups of metabolites include isonitrile derivatives, alkaloids and endoperoxide derivatives. The following discussion evidences that antimalarial marine molecules can efficiently integrate the panel of lead compounds isolated from terrestrial sources with new chemical backbones and, sometimes, with unique functional groups.
Use of Vegetation Health Data for Estimation of Aus Rice Yield in Bangladesh
Authors: Rahman Atiqur , Roytman Leonid , Krakauer Nir  Y. , Nizamuddin Mohammad , Goldberg Mitch
Published: April 2009

Rice is a vital staple crop for Bangladesh and surrounding countries, with interannual variation in yields depending on climatic conditions. We compared Bangladesh yield of aus rice, one of the main varieties grown, from official agricultural statistics with Vegetation Health (VH) Indices [Vegetation Condition Index (VCI), Temperature Condition Index (TCI) and Vegetation Health Index (VHI)] computed from Advanced Very High Resolution Radiometer (AVHRR) data covering a period of 15 years (1991–2005). A strong correlation was found between aus rice yield and VCI and VHI during the critical period of aus rice development that occurs during March-April (weeks 8–13 of the year), several months in advance of the rice harvest. Stepwise principal component regression (PCR) was used to construct a model to predict yield as a function of critical-period VHI. The model reduced the yield prediction error variance by 62% compared with a prediction of average yield for each year. Remote sensing is a valuable tool for estimating rice yields well in advance of harvest and at a low cost.
Silica-bound benzoyl chloride mediated the solid-phase synthesis of 4H-3,1-benzoxazin-4-ones
Authors: Rad-Moghadam Kurosh , Rouhi Somayeh
Published: April 2009

The solid-phase synthesis of 4H-3,1-benzoxazin-4-ones was achieved using silica-bound benzoyl chloride (SBBC) as dehydrating agent in reaction with 2-acylaminobenzoic acids. The silica-grafted reagent (SBBC) was simply recovered after reaction and reused several times.
Del pergamino al bit. La influencia del soporte en el contenido
Authors: Nistal Ana
Published: April 2009

El libro moderno de papel ha sido, sin duda, uno de los instrumentos más revolucionarios en la historia europea; su aparición fue posible gracias a las nuevas tecnologías de impresión y edición en papel. El cambio que supuso el desarrollo industrial de los libros cambió totalmente la concepción de los creadores, distribuidores y lectores. Los nuevos y modernos soportes propiciaron nuevas formas para crear contenidos antes imposibles. La tecnología digital está propiciando otra gran revolución que amenaza con cambiar el mundo del libro, no sólo en cuanto al soporte físico, sino a su concepto como libro aislado, delimitado por unas tapas de cartón, con un principio y un fin concretos. El gran cambio no es el paso de letras impresas a bits, sino el paso de libros aislados a libros “conectados”, a los que se puede acceder mediante infinitas fórmulas (o “conexiones”) en oposición a los libros cerrados de la era Gutenberg.
La era de las máquinas lectoras
Authors: Millán José Antonio
Published: April 2009

Las máquinas llevan años leyendo nuestros textos, tanto digitales como impresos. Su lectura de lo que escribimos forma parte ya del modo en que accedemos a la información y la creamos.
Cultura digital y memoria en red
Authors: Echeverría Javier
Published: April 2009

El sistema tecnológico TIC (tecnologías de la información y la comunicación) genera el espacio electrónico, los objetos digitales y una memoria distribuida. El desarrollo en la sociedad de la información implica el problema estructural de preservar esa memoria digital, en particular los objetos “de origen digital”, que sólo existen en red. Se analizan los principios promovidos por la UNESCO en su carta para la preservación de la memoria digital (2003) y se afirma que el patrimonio público debería ser conservado en software libre, garantizando el acceso abierto y universal a esos nuevos bienes culturales. Asimismo se analiza el problema de la sostenibilidad del patrimonio digital, que corre el riesgo de desaparecer a causa del veloz ritmo de cambio tecnológico del sistema TIC. Ello da lugar a una nueva modalidad de brecha digital, la brecha mnemónica.
Es un repositorio, es un depósito, es un archivo...: Open Access, colecciones digitales y valor
Authors: Guédon Jean-Claude
Published: April 2009

En el contexto del Acceso Abierto a la literatura científica y académica, los repositorios, tanto los institucionales como los disciplinares o temáticos, van a jugar un papel importante. No obstante, resulta difícil caracterizar la naturaleza de los repositorios debido a que cada categoría de personas relacionadas con ellos parecen tener diferente perspectiva. La cambiante interpretación que han teniendo los repositorios ha constituido una fuente de debilidad para la promoción de este instrumento. Aquí se sugiere que esta situación no se da sólo en el caso de los repositorios; al contrario, como muestran algunos importantes estudios provenientes de la escuela de pensamiento que aboga por la “Construcción social de la tecnología”, todos los objetos sociotécnicos pasan por la misma fase. Esta escuela sugiere que los objetos técnicos tienen éxito cuando los grupos sociales relevantes interpretan el significado y la función de una tecnología particular. Examinando un conjunto de eventos acerca de los repositorios, en particular las luchas alrededor de la posibilidad de obligar a autoarchivar los artículos, es posible identificar un buen número de grupos sociales, así como examinar el modo en que pueden aliarse entre sí o manifestar la conflictiva falla que los separa. Este tipo de análisis debería ayudar a desarrollar estrategias que permitan desarrollar los repositorios.
La «cultura convergente» y la filosofía Web 2.0 en la reformulación de la comunicación científica en la era del ciberperiodismo
Authors: Elías Carlos
Published: April 2009

Internet ha modificado profundamente la relación que siempre ha existido entre el periodista y su fuente, la comunicación entre los propios científicos y entre la fuente científica y la sociedad. Ahora cualquier periodista, científico, blogger o curioso puede acceder sin problema a la web de la fuente científica. La propia fuente (por ejemplo, la NASA) se considera entonces un medio de comunicación de masas a todos los efectos. Debido a ello, muchos científicos comienzan a producir ciencia para alimentar a “su medio de comunicación”. La ciencia acepta la dictadura de la audiencia. En una disciplina tan internacional como la ciencia, el nuevo entorno cibernético lo ha cambiado todo. En este artículo se analizan estos cambios bajo la perspectiva del nuevo paradigma de la “cultura convergente” y del desarrollo creciente de la filosofía Web 2.0.
Key to Nature: Herramientas digitales para la enseñanza de biodiversidad
Authors: Ferrer Canal Marina , Castroviejo Bolíbar Santiago
Published: April 2009

Key to Nature es un proyecto europeo que tiene como objetivo la implementación de herramientas digitales para la enseñanza de la biodiversidad. Participan en él 14 instituciones públicas y privadas de 11 países europeos, representando diferentes roles, como proveer datos (Real Jardín Botánico de Madrid, Museo de Historia Natural de Londres entre otros), y ofrecer las últimas innovaciones en aprendizaje digital (Centro de Investigación de “Usabilidad” de la Universidad de Lovaina, Bélgica, Giunti Labs, Italia...). El proyecto, de 4,8 millones de presupuesto de los cuales la mitad los financia la Comunidad Europea, tiene una duración de tres años y se encuentra ahora concluyendo el primero.
Using stories to assist storytelling in a pastoral setting: Four female pastors in dialogue with Mary Magdalene
Authors: De Beer Sanrie , Müller Julian
Published: April 2009

Sometimes we need a source of encouragement for restoring our own lives, to help us re-create ourselves. Using text as narrative texts opens up a multitude of possibilities in the work with clients in therapy. The story of Mary Magdalene told in John 20:11–18 is considered to be a healing story. This article aims to retell the story of her encounter with the resurrected Jesus, using the Gospel of Mary as an enlightening intertext. Because the story of Mary Magdalene’s encounter with Jesus is used as a healing story, the basic principles of transformative narrative theory are considered to be useful in the analysis of this text. Mary Magdalene’s story is then discussed with three female pastors of the Netherdutch Reformed Church of Africa. The research opened up a discussion about spirituality. This article would be incomplete without reflecting on the spirituality stories of the group of co-researchers.
Cardiovascular Agents
Authors: Joshi Gajanan S. , Burnett James C.
Published: April 2009

Cardiovascular disease still remains the nation's number one killer of men and women of all races, in spite of tremendous advances in basic and clinical research greatly helping to improve the prevention, treatment, and mortality of heart disease. It is estimated that ∼40% of Americans (∼60 million between the ages of 40–70) suffer from some degree of this disease. The problem of treating heart diseases has been at the forefront of the international medical community, and the cardiovascular drug market has been leading the drug discovery efforts in sales for the past two decades. A constant flow of new and effective drugs has kept this sector in its number one position and will continue to do so in the future.

The development of unique, novel, and tissue specific cardiac drugs to replace or supplement existing therapies for various cardiac disorders continues to generate significant and growing attention. This has evolved hand‐in‐hand with research that has facilitated a better understanding of the underlying causes of cardiac disease states. The first draft of the human genome map is a turning point in the research for new medicines that will address the cause, versus the symptoms, of many human ailments including cardiovascular diseases.

This article focuses on the review of past treatments, significant new developments, and future therapies for the treatment of various cardiovascular diseases. The article is divided into six sections: antiarrhythmic agents, antianginal agents, antihypertensive agents, antilipemic agents, antithrombolytic agents, and other therapeutics. Each section is further discussed in depth as per the classification of agents based upon their mechanism of action and clinical application. This article is designed primarily to serve the needs of a wide audience.
Chlorine
Authors: Bommaraju Tilak V. , Lüke Benno , O'Brien Thomas F. , Blackburn Mary C.
Published: April 2009

Chlorine, produced by the electrolysis of aqueous solutions of sodium chloride, is one of the top 10 commodity chemicals, in terms of capacity, in the United States. Chlorine is used for manufacturing a wide variety of organic and inorganic chemicals, in addition to being used in paper and pulp production and for water treatment. This article reviews the fundamental aspects related to the production of chlorine, electrolytic cell technologies to manufacture chlorine, with focus on the modern ion‐exchange cells, brine purification schemes, and chlorine processing steps. Furthermore, the physical and chemical properties of chlorine are listed along with the storage, transportation and environmental aspects related to chlorine.

The current market profile of chlorine and its future growth opportunities are presented here, with a listing of the present operating chlorine plants in the United States.
Keep the Change: using Reflection to Frame the Transformative Qualities of Learning
Authors: Peck Adam
Published: April 2009

A Week of Reflection brings learning outcomes to the center stage of teaching and learning at Saint Louis University.
Funktionale molekulare Reaktionskolben: neuartige Eigenschaften und Reaktionen in diskreten, selbstorganisierten Wirtmolekülen
Authors: Yoshizawa Michito , Klosterman Jeremy K. , Fujita Makoto
Published: April 2009

Auf kleinstem Raum: Selbstorganisierte Wirtmoleküle können als „molekulare Reaktionskolben“ die Reaktivitäten und Eigenschaften von Gastmolekülen verändern, die den räumlichen Einschränkungen ihrer wohldefinierten Hohlräume ausgesetzt sind. Vielfältige funktionale Wirte mit unterschiedlichen Größen, Formen und Anwendungsmöglichkeiten wurden mithilfe der einfachen, modularen Konzepte der supramolekularen Chemie hergestellt.

magnified image

Der Einsatz von selbstorganisierten Wirtmolekülen als “molekularen Reaktionskolben” hat das Interesse an der Reaktivität und den Eigenschaften von Molekülen in definierten Hohlräumen unter räumlicher Einschränkung enorm gesteigert. Die modulare Synthese selbstorganisierter Wirte ist einfach, und es wurden Systeme mit verschiedenen Größen, Formen und Eigenschaften hergestellt. In diesem Aufsatz gehen wir zunächst kurz auf die unterschiedlichen molekularen Reaktionskolben ein und konzentrieren uns anschließend auf ihren Einsatz als funktionale molekulare Behälter, besonders für den Einschluss von Gastmolekülen zur Verwirklichung ungewöhnlicher Reaktionen und zur Beobachtung einzigartiger chemischer Phänomene. Diese selbstorganisierten Hohlräume können als neuartige Phase angesehen werden, in der Reaktionen ablaufen, die in fester, flüssiger oder gasförmiger Phase nicht möglich sind.
Schulinspektion in Schweden
Authors: Schmidt Hans‐Jürgen
Published: April 2009

Seit Jahrzehnten und auch heute noch arbeiten die Schweden daran, ihr Bildungswesen so zu organisieren, dass möglichst Viele eine gute Ausbildung bekommen. Besonders die Schwachen sollen gefördert werden und diejenigen, die „vom Wege abgekommen”︁ sind. So können Schülerinnen und Schüler, deren Schulnoten in den Hauptfächern Schwedisch, Mathematik oder Englisch nicht ausreichen, an einem Förderunterricht teilnehmen [1]. Eine weitere Chance bekommen diejenigen, deren Noten auf dem Abgangszeugnis des Gymnasiums nicht ausreichen, um zu studieren. Ihnen werden einjährige Kurse an einem Komvux, der kommunalen Erwachsenenbildung, oder/und einjährige Vorkurse an einer Universität angeboten. Für Studierwillige, die bereits im Beruf stehen, aber keine HochschulZugangsberechtigung haben, wurde 1977 die Hochschulprüfung eingerichtet, die inzwischen allen offensteht [2]. Wie wird dieses komplexe System gesteuert?
Local existence for the free boundary problem for nonrelativistic and Relativistic compressible Euler equations with a vacuum boundary condition
Authors: Trakhinin Yuri
Published: April 2009

We study the free boundary problem for the equations of compressible Euler equations with a vacuum boundary condition. Our main goal is to recover in Eulerian coordinates the earlier well‐posedness result obtained by Lindblad [11] for the isentropic Euler equations and extend it to the case of full gas dynamics. For technical simplicity we consider the case of an unbounded domain whose boundary has the form of a graph and make short comments about the case of a bounded domain. We prove the local‐in‐time existence in Sobolev spaces by the technique applied earlier to weakly stable shock waves and characteristic discontinuities [5, 12]. It contains, in particular, the reduction to a fixed domain, using the “good unknown” of Alinhac [1], and a suitable Nash‐Moser‐type iteration scheme. A certain modification of such an approach is caused by the fact that the symbol associated to the free surface is not elliptic. This approach is still directly applicable to the relativistic version of our problem in the setting of special relativity, and we briefly discuss its extension to general relativity. © 2009 Wiley Periodicals, Inc.
Improving TCP performance for vertical handover in heterogeneous wireless networks
Authors: Kim Hojin , Lee SuKyoung
Published: April 2009

The incorporation of wireless local area networks (WLANs) into existing cellular networks as supplementary access technologies has become an issue of great interest. However, vertical handover (VHO), which allows users to roam between a WLAN and a cellular network, causes an abrupt change in certain link characteristics such as the round trip time and data rate. Owing to such changes, reordering problem and premature timeout occur and trigger unnecessarily fast retransmission during VHO, causing throughput degradation. Thus, we propose a new transmission control protocol (TCP) mechanism, which resolves the reordering problem by suppressing unnecessary retransmission caused by spurious duplicate acknowledgments (dupacks) incurred because of the reordering problem, and prevents premature timeout by employing an adaptive retransmission timer. We analytically investigate the throughput of our proposed TCP scheme. The numerical and simulation results show that our proposed TCP performs better in terms of throughput than other schemes appearing in the literature. Copyright © 2009 John Wiley & Sons, Ltd.
Chromosomal mobilization and reintegration of Sleeping Beauty and PiggyBac transposons
Authors: Liang Qi , Kong Jun , Stalker James , Bradley Allan
Published: April 2009

The Sleeping Beauty and PiggyBac DNA transposon systems have recently been developed as tools for insertional mutagenesis. We have compared the chromosomal mobilization efficiency and insertion site preference of the two transposons mobilized from the same donor site in mouse embryonic stem (ES) cells under conditions in which there were no selective constraints on the transposons' insertion sites. Compared with Sleeping Beauty, PiggyBac exhibits higher transposition efficiencies, no evidence for local hopping and a significant bias toward reintegration in intragenic regions, which demonstrate its utility for insertional mutagenesis. Although Sleeping Beauty had no detectable genomic bias with respect to insertions in genes or intergenic regions, both Sleeping Beauty and PiggyBac transposons displayed preferential integration into actively transcribed loci. genesis 47:404–408, 2009. © 2009 Wiley‐Liss, Inc.
Does contact dermatitis to fragrances influence the quality of life? A descriptive study measuring and comparing the quality of life and skin involvement in patients with contact dermatitis to fragrances
Authors: Sanchez‐Politta S. , Pashe F. , Naldi L. , Piletta P.
Published: April 2009

The study of the impact of diseases on individuals' quality of life is an important and useful tool for clinicians, particularly for an efficient follow‐up and for the good management of patients suffering from chronic diseases. Contact dermatitis is a common condition in dermatological patients. However, despite efficient screening, the understanding and acceptance of contact allergy remain difficult and avoidance of these allergens is not always possible. The aim of this study was to determine whether contact dermatitis to fragrances affects quality of life and to define whether there is a relationship between the severity of skin involvement and quality of life. To measure the quality of life, we chose the VQ‐Dermato (VQ‐d) questionnaire, the only valid and reliable questionnaire in French, to which we added 10 non‐validated specific questions regarding fragrances. We included patients with pertinent positive patch test reactions to fragrances attending the contact clinic between 1 January 1998 and 30 September 2004. During this time, 2814 patients were patch tested and 310 had positive reactions to the fragrance mix 8% (FM) of the standard series. We recruited non‐atopic individuals, exclusively allergic to fragrance mix, with patch test reactions scored ++ and +++; the only additional positive reactions accepted were to balsam of Peru and the patient's own perfumes; 52 patients met these criteria, but only 33 participated. To evaluate the severity of skin involvement, we used the severity scoring of atopic dermatitis (SCORAD index). The quality of life of individuals allergic to fragrances was mostly moderately affected. Patients were more affected psychologically during the first year after the diagnosis of fragrance allergy. Skin reaction during the acute stage of contact allergy to fragrances can be severe. No correlation between VQ‐d and SCORAD could be established. It was concluded that there was no severe impact on quality of life because of fragrance contact allergy, but that psychological issues and depression may play an important role in determining the way skin disease affects people. Patch testing improves the quality of life. Lack of correlation between VQ‐d and SCORAD demonstrates that an objective measure such as SCORAD may not fully capture the impact of the disease. These results cannot be generalized because of the low response rate and limited sample size. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of some 6‐methoxyimidazo[1,2‐b]pyridazines
Authors: Lombardino Joseph G.
Published: April 2009

The synthesis of 6‐methoxyimidazo[1,2‐b]pyridazine and its 2‐methyl analog is reported. Carboxylic acids, esters and quaternary salts derived from this ring system are described and the heterocyclic system is shown to undergo the Mannich reaction. A condensation reaction of the 2‐methyl group is reported and nuclear magnetic resonance (nmr) spectra and acidity constants of some imidazo[1,2‐b]pyridazines are recorded.
1‐(2‐Mercaptoethyl)phthalazines and related compounds
Authors: Castle Raymond N. , Takano Seiichi
Published: April 2009

1‐(2‐Mercaptoethyl)phthalazine (VII) and its analogs such as S‐2‐(1‐phthalazyl)ethyliso‐thiuronium bromide (VI), sodium S‐2‐(1‐phthalazyl)ethylthiosulfate (VIII), 1,3‐bis‐acetylthio‐2‐(1‐phthalazyl)propane (XII), 2‐(1‐phthalazyl)‐1,3‐propanedithiol (XIII), disodium 2‐(1‐phthalazyl)‐1,3‐propanedithiosulfate (XIV), 3‐dimethylamino‐2‐(1‐phthalazyl)‐1‐propanethiol (XVII) and 3‐(4‐methyl‐1‐piperazinyl)‐2‐(1‐phthalazyl)‐1‐propanethiol (XIX) have been prepared as potential radiation protection agents.
The chemistry of cyclic enaminoketones. III. Synthesis of bi‐ and tricyclic enaminoketones from enamine esters and nitriles
Authors: Meyers A. I. , Reine A. H. , Sircar J. C. , Rao K. B. , Singh S. , Weidmann H. , Fitzpatrick M.
Published: April 2009

The cyclization of enamines derived from β‐aminoesters and β‐aminonitriles into bi‐ and tricyclic enaminoketones (6,9,13 and 24) has been investigated. The enamines derived from aminonitriles cyclize smoothly with magnesium perchlorate in benzene or toluene, whereas the enamines derived from aminoesters cyclize spontaneously during their formation. The scope and limitation of this process is discussed.
Synthesis and spectral properties of some 1,2‐dithienylethenes and 1‐thieny1‐4‐phenylbutadienes
Authors: Campaigne E. , Fleming William L. , Dinner Alan
Published: April 2009

A total of seven thiophene derivatives not previously reported have been prepared via the Knoevenagel condensation of an activated methylthiophene and a heterocyclic or aromatic aldehyde. The principal peaks in the ultraviolet and visible absorption spectra as well as some nuclear magnetic resonance data are reported for these compounds.
Antimalaria agents II. Synthesis and reactions of 3‐([p‐(4‐nitrophenyl)sulfonyl] phenyl)sydnone
Authors: Singhal Gopal H. , Popoff Ivan C.
Published: April 2009

The synthesis and several reactions of a sydnone substituted with strongly electron‐withdrawing substituents are described. Infrared evidence for labile open chain iminoanhydride is presented.
Cu(I) substitutions. furo[3,2‐b] pyridines, furo[3,2‐c] pyridines and 1h‐thieno[3,4‐b] 2‐pyran‐l‐ones from cuprous acetylides
Authors: Mladenović S. A. , Castro C. E.
Published: April 2009

The reaction of cuprous acetylides with aryl halides bearing a nucleophilic ortho substituent provides a versatile route to heterocyclic substances. The present work portrays the ease with which polyheterosystems can be constructed with this reaction. The synthesis of 2‐substituted 7‐iodofuro[3,2‐c]pyridines, 2‐substituted furo[3,2‐b]pyridines, and 3‐substituted lH‐thieno‐[3,4‐b]‐2‐pyran‐l‐ones (thiaisocoumarins) is described. The latter two ring systems have not been previously reported.
An investigation of the abnormal products from the reaction of 2‐thenyl and benzyl grignard reagents by gas chromatography.
Authors: Campaigne E. , Johnson Roger E.
Published: April 2009

The products of the reaction of 2‐thenylmagnesium chloride (I) with a variety of reagents has been studied by gas chromatography. Carbon dioxide and ethylene oxide produced significant amounts of 5‐substituted (“para”) products as well as 3‐substituted (“ortho”) and normal addition products. Several other reagents, including acetyl chloride and formaldehyde, produced mainly “ortho” products along with small amounts of normal products. The dependence of product distribution on temperature, added salts and solvent character was found to correlate with the reported rates of inversion about the carbon‐magnesium bond in primary Grignard reagents. Blocking the “ortho” position, in 3‐methyl‐2‐thenylmagnesium chloride, increased the proportion of “para” product from 3 to 33%. In addition, the reactions of benzylmagnesium chloride with certain reagents were re‐examined.
Electrophilic substitution of dibenz[b,f]oxepin
Authors: Bavin P. M. G. , Bartle K. D. , Jones D. W.
Published: April 2009

Dibenz[b,f]oxepin undergoes nitration and acid‐catalyzed deuteration at the 10‐position and adds bromine across the 10,11 bond. These reactions contradict predictions made by the SCFMO method. Chemical reactions and NMR spectroscopy suggest that dibenz[b,f]oxepin is only weakly aromatic.
Synthesis of 5,6‐dihydro‐8‐methoxy‐4H‐imidazo[4,5,1‐ij]quinolines and some related ring systems
Authors: Werbel Leslie M. , Battaglia Josephine , Zamora Maria L.
Published: April 2009

Reduction of amides of 8‐amino‐6‐methoxyquinoline over platinum oxide in glacial acetic acid at room temperature affords 2‐substituted‐5,6‐dihydro‐8‐methoxy‐4H‐imidazo [4,5,1‐ij]‐quinolines (I). The method could not be utilized for urea or carbamate derivatives of 8‐amino‐6‐methoxyquinoline. 2‐Amino derivatives of I were prepared through the chloro compound obtained from 5,6‐dihydro‐8‐methoxy‐4H‐imidazo[4,5,1‐ij]quinolin‐2(1H)‐one, (IV). Several related ring systems have also been prepared.
Pyrimidine N‐oxides. Oxidation of 5‐nitroso‐2,4,6‐triaminopyrimidine
Authors: Delia T. J. , Portlock D. E. , Venton D. L.
Published: April 2009

The peroxytrifluoroacetic acid oxidation of 5‐nitroso‐2,4,6‐triaminopyrimidine (1b) led to the formation of two products: 5‐nitro‐2,4,6‐triaminopyrimidine 1‐N‐oxide (2) and 5‐nitro‐2,4,6‐triaminopyrimidine 1‐3‐di‐N‐oxide (3). On the basis of previous experience 2 was the sole expected oxidation product. However, 3 represents a rather unexpected development in that di‐N‐oxides in the pyrimidine series are uncommon. The yields are good for both products and structures are assigned on the basis of elemental analysis, mass spectral data, and chemical reactions. The reaction sequence is also discussed.
The preparation of 2H‐1,2,3‐benzothiadiazine‐1,1‐dioxides, 11H‐11a‐dihydrobenzimidazo[1,2‐b] [1,2] benzisothiazole‐5,5‐dioxides, 6H‐dibenzo[c,g] [1,2,5] thiadiazocine‐5,5‐dioxides and 5H‐Dibenzo[c,g] [1,2,6] thiadiazocine‐6,6‐dioxides
Authors: Wright John B.
Published: April 2009

o‐Benzoylbenzenesulfonyl chlorides (I) were prepared conveniently from aminobenzophenones by diazotization followed by reaction with sulphur dioxide in the presence of Cu+, according to the general method of Meerwein.

Reaction of the sulfonyl chlorides with hydrazine led to 4‐phenyl‐2H‐1,2,3‐benzothiadiazine‐1,1‐dioxides (II). The latter compounds could be methylated and acetylated readily in the 2‐position. The 2‐methyl derivative (III) could be prepared also by reaction of the sulfonyl chloride (Ia) with methylhydrazine. Catalytic hydrogenation of 6‐chloro‐4‐phenyl‐2H‐1,2,3‐benzothiadiazine‐1,1‐dioxide (IIa) gave the 3,4‐dihydro derivative (V). Reaction of the sulfonyl chlorides (I) with o‐phenylenediamine followed by cyclodehydration led to 11H‐11,11a‐dihydrobenzimidazo[1,2‐b] [1,2]benzisothiazole‐5,5‐dioxides (VII). One of the latter compounds (VIIa) in sodium hydroxide solution in the presence of methyl iodide or benzyl chloride was transformed into 6‐methyl‐ and 6‐benzyl‐5H‐dibenzo[c,g] [1,2,6]thiadiazocine‐5,5‐dioxides (VIII), respectively.

5H‐Dibenzo[c,g] [1,2,6] thiadiazocine‐6,6‐dioxides (XIV) were prepared also by cyclodehydration of 2‐amino‐2′‐benzoylbenzenesulfonanilides (XIII).
Reissert compound studies. XVII. Phosphorus‐containing reissert compound analogues
Authors: Spatz David M. , Popp Frank D.
Published: April 2009

The reaction of isoquinoline, potassium cyamide, and chlorophosphates or chlorothiophosphates leads to the formation of phosphorus containing analogues of Reisert compounds. These analogues can be converted by base to an anion which undergoes elimination to isoquinaldonitrile or which can be alkylated. Acid‐catalysed hydrolysis of the analogues leads to isoquinoline.
Synthesis of pyridazine derivatives XXII. s‐triazolo[4, 3‐b]pyridazine 5‐oxides
Authors: Pollak A. , Stanovnik B. , Tisler M.
Published: April 2009

The synthesis of s‐triazolo[4,3‐b] pyridazine 5‐oxides is reported. To our knowledge, they are the first example of N‐oxides of heteroaromatic azoloazines with a bridgehead nitrogen. They are easily rearranged, in particular when irradiated with ultraviolet light, into 6‐hydroxy‐s‐triazolo[4,3‐b]pyridazines.
2‐Amino‐2‐thiazoline. V. phenylthioureido and phenylureido derivatives of 2‐thiazoline
Authors: Klayman Daniel L. , Maul James J. , Milne George W. A.
Published: April 2009

The reaction of 2‐amino‐2‐thiazoline (I) with phenylisothiocyanate has been reported to give 2‐imino‐3‐phenylthiocarbamoylthiazolidine (II) at low temperatures and l‐phenyl‐3‐(2‐thiazolin‐2‐yl)‐2‐thiourea (III) at ca. 100°. When performed by us, however, this reaction gave only a single mono‐adduct regardless of the temperature. Nmr and chemical evidence indicates that structure III is the correct one. Treatment of I with phenylisocyanate also gave a mono‐adduct which was established to be l‐phenyl‐3‐(2‐thiazolin‐2‐yl)urea (V). Compound I does not form a simple di‐adduct with excess phenylisothiocyanate but does so with phenylisocyanate to give 2‐phenylcarbamoylimino‐3‐phenylcarbamoylthiazolidine (VI). The reaction of III with phenylisocyanate gives 2‐phenylthiocarbamoylimino‐3‐phenylcarbamoylthiazolidine (VII), however, the corresponding reaction of V with phenylisothiocyanate does not give the anticipated product but a mixture of compounds which includes VI and VII.
Synthetic Amebicides. VIII. 7,7′‐[Iminobis(alkyleneimino) [bis[benz[c] acridines] and Congeneric 9‐Aminoacridines, 12‐Aminobenz[a] acridines, [2‐Aminobenz[b] acridines, and 4‐Aminoquinolines
Authors: Elslager Edward F. , Short Franklin W. , Tendick Frank H.
Published: April 2009

Thirty‐five 7,7′‐(iminodialkylenediimino))bis[benz[c]acridines] (VII), 7,7′‐(alkylene‐ and phenylenediimino)bis[benz[c]acridines] (VIII and IXa‐c), [iminobis(alkyleneimino)]bis[acridines, benz[a]acridines, benz[b]acridines, and quinolines] (X, Xla‐c, XII, XIII, and XIVa‐c), and [alkylenebis(iminoalkyleneimino)]bis[acridines, benz[c]acridines, and quinolincs] (XVI, XVII, XVIIIa and b, and XIXa‐c) were synthesized by the condensation of one equivalent of the appropriate alkylenediamine with two equivalents of the requisite chloroheterocycle in phenol. Many of the bis(aminoheterocyclic) compounds are highly active against Entamoeba histolytica in vitro and in experimental animals.
Acylation of nitrogen heterocycles. II . Carbobenzoxylation of substituted adenines under the conditions of the schotten‐baumann reaction
Authors: Altman J. , Ben‐Ishai D.
Published: April 2009

9‐Benzyladenine, 6‐benzylamino‐9‐benzyladenine, 6‐piperidino‐9‐benzyladenine and 2′,3′‐O‐isopropylidene‐5′‐trityladenosine underwent a Bamberger fission of the imidazole ring when treated with carbobenzoxy chloride in aqueous base. Under similar experimental conditions adenine itself afforded two monoacyl derivatives.
Organosilicon compounds VI. The preparation of silylaziridines and silyldiaziridines by silicon‐carbon cleavage
Authors: Thames Shelby E. , McClesky Josef F. , Kelly Phillip L.
Published: April 2009

The preparation of several 2‐furyl‐, 2‐thienyl‐, benzyl‐, and allylsubstituted silanes is reported. Such derivatives, when treated with aziridine in the presence of a metal catalyst, afford good yields of silylaziridines and silyldiaziridines. A qualitative study of electronic and steric requirements of the displacement reaction is reported.
Sterically‐crowded pyrroles
Authors: Broadbent H. Smith , Burnham Weldon S. , Olsen Richard K. , Sheeley Richard M.
Published: April 2009

The syntheses in good yields of a considerable number of moderately to severely sterically‐crowded 1,2,5‐trisubstituted pyrroles by means of modifications of the Knorr‐Paal condensation are described. Notwithstanding reports to the contrary, the classical procedure; succeeded in moderately sterically‐crowded cases, e.g., R2 = R5 = Me, R1 = i‐Pr, Me2CHMeCH‐, Me2N‐, Ph2N‐, 9‐carbazolo, subst. 4‐morpholino, 1‐piperazino, 1‐piperidino, etc. A product‐water azeotroping procedure succeeded in more severely sterically‐crowded cases e.g., R2 = R5 = Et, R1 = i‐Pr; R2 = R5 = Me, R1 = Me3CCH2‐, R2 = R5 = i‐Pr, R1 = PhCH2‐. Highly sterically‐crowded pyrroles, e.g., R2 = R5 = Me, R1 = t‐Bu, adamantyl, PhCH2CMe2; R2 = R5 = Et, R1 = t‐Bu; R1 = R2 = R5 = i‐Pr; R2 = R5 = t‐Ru, R1 = Me, Et, PhCH2‐, were obtained using titanium tetrachloride as a Lewis acid catalyst and as a water scavenger. Infrared spectra of the reacting mixtures provided evidence pertinent to the mechanism of the reaction, which is discussed.