bluuebunny/crossref_metadata_2025 huggingface dataset:
Women's Mobilization and Gender Outcomes in Transitions to Democracy
Authors: Waylen Georgina
Published: May 2007

This article explores the conditions under which women's mobilizations during transitions to democracy can achieve some of their aims. It broadens the comparative analysis of gender and transitions undertaken to date by looking at a case in which gender outcomes, measured in terms of women's descriptive and substantive representation, have been relatively positive. Unusually women, organized as women, had some input into the negotiations during the South African transition. The article argues that a complex interaction of variables contributed to the achievement of certain positive gender outcomes. A broad women's coalition, the Women's National Coalition, did play an important role. However, two other sets of factors—a favorable political opportunity structure and the strategic actions and alliances of certain key women actors— made a crucial contribution to its effectiveness in influencing this transition, as women's mobilization on its own is no guarantee of success.
Challenges for Foreign-Owned Subsidiaries in FDI-Led Modernization Strategies: The Case of Hungary
Authors: Dörrenbächer Christoph
Published: May 2007

Many Central and Eastern European Countries are intensively pursuing a strategy of foreign-led modernization. This strategy puts foreign multinational corporations in a strategic role not only with regard to industrial upgrading but also with regard to wider social and macroeconomic issues. Using the case of Hungary, the paper first demonstrates that foreign-led modernization strategies are subject to medium- and sometimes even short-term changes. Thus, with privatization investments and labour-intensive greenfield investments losing ground in Hungary after the turn of the century, foreign subsidiaries already present in the country and their further upgrading became the focal point of Hungary's modernization strategy. Starting from here, the paper explores the question of what are the necessary pre-requisites for foreign subsidiaries in Hungary to successfully develop their role and hence support the overall modernization strategy. Three case studies reveal that access to headquarters, commitment to location and access to unique resources are the most important pre-requisites for subsidiaries to develop their role. In the concluding section, the paper addresses the paradoxical nature of this variant of foreign-led modernization strategy, that, on the one hand, is promoting industrial upgrading but, at on the other hand, is very likely to deepen the basis for social, regional and economic inequality.
Power and Influence: Russian Energy Behavior in Central Asia
Authors: Sabonis-Helf Theresa
Published: May 2007

Russian energy behavior is examined with regard to the oil, electricity and gas sectors in each of the Central Asian states, and each state's responses to that behavior. The contention is that the Central Asian states, in spite of disarray in the energy sectors, have attempted to develop strategies which treat energy as a strategically sensitive commodity, and account for Russia's interests while protecting their own. The adaptive capacity of the Central Asian states varies from state to state – but also from sector to sector, and the article examines why that has been the case. The analysis concludes with an exploration of how Russia's energy strategies in Central Asia may fit into the wider context of Russia's market and political strategies.
Activation of mitogen-activated protein kinase kinase (MEK)/extracellular signal–regulated kinase (ERK) signaling pathway is involved in myeloid lineage commitment
Authors: Hsu Chia-Lin , Kikuchi Kazu , Kondo Motonari
Published: May 2007

Common lymphoid progenitors (CLPs) are lymphoid-lineage-committed progenitor cells. However, they maintain a latent myeloid differentiation potential that can be initiated by stimulation with interleukin-2 (IL-2) via ectopically expressed IL-2 receptors. Although CLPs express IL-7 receptors, which share the common γ chain with IL-2 receptors, IL-7 cannot initiate lineage conversion in CLPs. In this study, we demonstrate that the critical signals for initiating lineage conversion in CLPs are delivered via IL-2 receptor β (IL-2Rβ) intracellular domains. Fusion of the A region of the IL-2Rβ cytoplasmic tail to IL-7Rα enables IL-7 to initiate myeloid differentiation in CLPs. We found that Shc, which associates with the A region, mediates lineage conversion signals through the mitogen activated protein kinase (MAPK) pathway. Because mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) inhibitors completely blocked IL-2-mediated lineage conversion, MAPK activation, specifically via the MEK/ERK pathway, is critically involved in the initiation of this event. Furthermore, formation of granulocyte/macrophage (GM) colonies by hematopoietic stem cells, but not by common myeloid progenitors (CMPs), was severely reduced in the presence of MEK/ERK inhibitors. These results demonstrate that activation of MEK/ERK plays an important role in GM lineage commitment.
MDM2 Polymorphism, Survival, and Histology in Early-Stage Non–Small-Cell Lung Cancer
Authors: Heist Rebecca Suk , Zhou Wei , Chirieac Lucian R. , Cogan-Drew Thea , Liu Geoffrey , Su Li , Neuberg Donna , Lynch Thomas J. , Wain John C. , Christiani David C.
Published: May 2007

Purpose

MDM2 is a negative regulator of p53. The MDM2 309T/G polymorphism has been associated with differential MDM2 expression levels and inhibition of the p53 pathway. We hypothesized that the MDM2 G/G genotype may be associated with worse survival outcomes in lung cancer, especially in squamous cell cancers where p53 abnormalities are more common.

Patients and Methods

We evaluated the relationship between MDM2 polymorphism status and overall survival (OS) among patients with early-stage non–small-cell lung cancer (NSCLC) treated with surgical resection at Massachusetts General Hospital from 1992 to 2000. Kaplan-Meier methods and the log-rank test were used to compare survival by polymorphism status. Cox proportional hazards models were used to adjust for possible confounding variables.

Results

There were 383 patients in the analysis. In the early-stage population as a whole, the G/G genotype seemed to be associated with worse OS on adjusted analysis (adjusted hazard ratio = 1.57; 95% CI, 1.03 to 2.40; P = .04). Among patients with squamous histology, OS was significantly worse among those with the G/G genotype (P = .0001 by log-rank test), with 5-year survival rates among the genotypes of 59% for T/T, 53% for T/G, and 7% for G/G.

Conclusion

Our findings suggest that the G/G genotype of the MDM2 polymorphism is associated with worse OS among early-stage NSCLC patients, particularly those with squamous cell histology.
The Index and the Algorithm
Authors: Soderman Braxton
Published: May 2007

braxton soderman is a third-year PhD candidate in the Modern Culture and Media program at Brown University. His most recent publication was entitled, “At the Crossroads of the Trivial,” published in The Electronic Journal of Communication. He is currently studying for his preliminary examinations.
TheDrosophilamuscle LIM protein, Mlp84B, cooperates with D-titin to maintain muscle structural integrity
Authors: Clark Kathleen A. , Bland Jennifer M. , Beckerle Mary C.
Published: May 2007

Muscle LIM protein (MLP) is a cytoskeletal LIM-only protein expressed in striated muscle. Mutations in human MLP are associated with cardiomyopathy; however, the molecular mechanism by which MLP functions is not established. A Drosophila MLP homolog, mlp84B, displays many of the same features as the vertebrate protein, illustrating the utility of the fly for the study of MLP function. Animals lacking Mlp84B develop into larvae with a morphologically intact musculature, but the mutants arrest during pupation with impaired muscle function. Mlp84B displays muscle-specific expression and is a component of the Z-disc and nucleus. Preventing nuclear retention of Mlp84B does not affect its function, indicating that Mlp84B site of action is likely to be at the Z-disc. Within the Z-disc, Mlp84B is colocalized with the N-terminus of D-titin, a protein crucial for sarcomere organization and stretch mechanics. The mlp84B mutants phenotypically resemble weak D-titin mutants. Furthermore, reducing D-titin activity in the mlp84B background leads to pronounced enhancement of the mlp84B muscle defects and loss of muscle structural integrity. The genetic interactions between mlp84B and D-titin reveal a role for Mlp84B in maintaining muscle structural integrity that was not obvious from analysis of the mlp84B mutants themselves, and suggest Mlp84B and D-titin cooperate to stabilize muscle sarcomeres.
Studies of the Selective Removal of Micro-Quantities of Platinum(IV) Ions from Macro-Quantities of Model Solutions of Aluminium, Copper, Iron, Nickel and Zinc Chloride on Anion-Exchangers of Various Types
Authors: Hubicki Z. , Wójcik G.
Published: May 2007

Platinum has been widely applied as an industrial catalyst and consequently the recovery of noble metals from industrial wastes has become an economic issue. In the present studies, laboratory tests were undertaken to examine the selective removal of micro-quantities of platinum(IV) from 1 M solutions of aluminium, copper, iron, nickel and zinc chloride in 0.1 M hydrochloric acid using anion-exchangers containing tertiary amine group functions (Amberlite IRA-67 and Amberlite IRA-93) and polyamine group functions (Diaion CR-20).

The values of the recovery factor [% R Pt(IV)] were determined for these anion-exchangers, as well as the sorption isotherms whose shape and type depended on the kind of aqueous phase employed and the phase contact time. In addition, the weight and volume distribution coefficients as well as the working and total ion-exchange capacities were calculated from the Pt(IV) breakthrough curves and various kinetic parameters were determined.

The anion-exchanger Amberlite IRA-93 exhibited a maximum working capacity for Pt(IV) ions.
A Suitable Load Control Method for Constant Tip Speed Ratio Operation of Stand-alone Wind Turbine-Generator Systems (Part 1: Evaluation of Power Generation Capability and Output Fluctuation)
Authors: Wakui Tetsuya , Yokoyama Ryohei
Published: May 2007

A suitable load control method for a constant tip speed ratio operation of stand-alone systems using vertical axis wind turbines with a self-starting capability is discussed from the viewpoint of its power generation capability and output fluctuations. This study takes up a stand-alone system with a straight-wing-type turbine, which is mainly operated at a constant tip speed ratio. Two types of load control methods are considered: Method-1 wherein the load torque is controlled in proportion to the square of the rotational speed and Method-2 that adopts a feedback control of the rotational speed in response to the inflow wind speed. The computational results using the dynamic simulation model show that the decrease in the output fluctuations from Method-1 to Method-2 is much larger than the increase in the power generation capability from Method-2 to Method-1. Therefore, it is concluded that Method-1 is the suitable load control method.
Recurrences in an Infection Model: A Medical Application of GI/M/s Loss Systems
Authors: Stadje Wolfgang
Published: May 2007

We consider a simple model for the evolution of a bacterial infection and its treatment for a population of s susceptible individuals. When an individual catches the disease, he or she is treated (e.g., by antibiotics) and is cured after a random amount of time. While being treated, an individual cannot be infected and will not transmit the disease to others. Every healthy individual is equally likely to be the next to catch the infection. The interarrival times of the occurrences of new bacteria are assumed to be i.i.d. random variables. We derive the distribution of the time S until some individual is infected for the second time and thus has to be treated again. The Laplace transform of S is given explicitly and in a more convenient recursive form. The model can be formulated as a GI/M/s loss system, and S can be viewed as the first time some service station starts working for its second customer. In the M/M/s case, the results simplify.
Existence of Approximate Exact Penalty in Constrained Optimization
Authors: Zaslavski Alexander J.
Published: May 2007

In this paper, we use the penalty approach in order to study constrained minimization problems in infinite dimensional spaces. A penalty function is said to have the exact penalty property if there is a penalty coefficient for which a solution of an unconstrained penalized problem is a solution of the corresponding constrained problem. In this paper, we establish the exact penalty property for a large class of inequality-constrained minimization problems.
When being a girl matters less: Accessibility of gender‐related self‐knowledge in single‐sex and coeducational classes and its impact on students' physics‐related self‐concept of ability
Authors: Kessels Ursula. , Hannover Bettina.
Published: May 2007

Background. Establishing or preserving single‐sex schooling has been widely discussed as a way of bringing more girls into the natural sciences.

Aims. We test the assumption that the beneficial effects of single‐sex education on girls' self‐concept of ability in masculine subjects such as physics are due to the lower accessibility of gender‐related self‐knowledge in single‐sex classes.

Sample. N = 401 eighth‐graders (mean age 14.0 years) from coeducational comprehensive schools.

Methods. Random assignment of students to single‐sex vs. coeducational physics classes throughout the eighth grade. At the end of the year, students' physics‐related self‐concept of ability was measured using a questionnaire. In a subsample of N = 134 students, the accessibility of gender‐related self‐knowledge during physics classes was assessed by measuring latencies and endorsement of sex‐typed trait adjectives.

Results. Girls from single‐sex physics classes reported a better physics‐related self‐concept of ability than girls from coeducational classes, while boys' self‐concept of ability did not vary according to class composition. For both boys and girls, gender‐related self‐knowledge was less accessible in single‐sex classes than in mixed‐sex classes. To the extent that girls' feminine self‐knowledge was relatively less accessible than their masculine self‐knowledge, their physics‐related self‐concept of ability improved at the end of the school year.

Conclusions. By revealing the importance of the differential accessibility of gender‐related self‐knowledge in single‐ and mixed‐sex settings, our study clarifies why single‐sex schooling helps adolescents to gain a better self‐concept of ability in school subjects that are considered inappropriate for their own sex.
Plant-Derived Flavanol (−)Epicatechin Enhances Angiogenesis and Retention of Spatial Memory in Mice
Authors: van Praag Henriette , Lucero Melanie J. , Yeo Gene W. , Stecker Kimberly , Heivand Neema , Zhao Chunmei , Yip Ed , Afanador Mia , Schroeter Hagen , Hammerstone John , Gage Fred H.
Published: May 2007

Diet and exercise have a profound impact on brain function. In particular, natural nutrients found in plants may influence neuronal survival and plasticity. Here, we tested whether consumption of a plant-derived flavanol, (−)epicatechin, enhances cognition in sedentary or wheel-running female C57BL/6 mice. Retention of spatial memory in the water maze was enhanced by ingestion of (−)epicatechin, especially in combination with exercise. Improved spatial memory was associated with increased angiogenesis and neuronal spine density, but not newborn cell survival, in the dentate gyrus of the hippocampus. Moreover, microarray analysis showed upregulation of genes associated with learning and downregulation of markers of neurodegeneration in the hippocampus. Together, our data show that ingestion of a single flavanol improves spatial memory retention in adult mammals.
Perspective: New New Religions: Revisiting a Concept
Authors: Melton J. Gordon
Published: May 2007

The concept of new new religions, which in Japan refers to a second generation of new religions formed after 1970, calls attention to a generation of new religions formed in the West since 1990 and largely neglected in new religions studies. The concept itself is less helpful in that it obscures the continuous year-by-year production of new religions in free societies. The fact that so many of the older new religions are being considered by the academy under their family groupings as Buddhist, Hindu, Jewish or Muslim sects, along with the demise of the brainwashing controversy, suggests that new religions studies needs a new direction. The many new new religions—those new groups with a high degree of both social and cultural alienation, many of a New Age Esoteric orientation—seem to be a logical innovative focus for new religions scholars.
Childhood Familial Experiences as Antecedents of Adult Membership in New Religious Movements: A Literature Review
Authors: Murken Sebastian , Namini Sussan
Published: May 2007

Is it possible to identify specific familial patterns as antecedents of adult membership in new religious movements? Can the choice of an NRM be predicted by the childhood experiences of individuals joining such movements? This international literature review seeks to answer these questions, investigating the assumption that early family experiences affect adults' decisions to join NRMs. It includes empirical studies that have been written in English, German and French since 1970, and gives an overview of findings on childhood family structures, including parents and siblings, as well as early family relationships and atmospheres. On the whole, the studies from different countries and decades support the hypothesis that early family experiences have an impact on adult membership in NRMs. However, it seems that individuals with different early experiences are attracted to different kinds of groups. Whereas many studies found problematic family backgrounds and absent fathers in converts' biographies, suggesting a compensatory function of membership, some point to a continuation or restoration of early experiences. More interdisciplinary comparative research on NRMs is needed to gain a better understanding of the psychodynamic processes and psychological offers of different groups.
Collective Identity and the Postcharismatic Fate of Shambhala International
Authors: Eldershaw Lynn P.
Published: May 2007

This study examines the postcharismatic fate of Vajradhatu/Shambhala International, one of the largest Buddhist communities in North America. Throughout its thirty-year history, the Shambhala movement has experienced a number of internal and external challenges. Following the untimely death of its founder, Chögyam Trungpa Rinpoche, in 1987, the movement experienced a crisis in succession that garnered international negative exposure and threatened its stability. This analysis draws on recent theorizing on collective identity to examine the manner in which this movement has survived the crisis and gone about reconstituting itself. It is proposed that recent transformations in Shambhala International are indicative of larger changes in the organization of religion within contemporary pluralist culture. This study provides much-needed ethnographic data on an empirically neglected new religious movement and adds to a growing body of literature tracing the growth of Buddhism in the West.
Intelligence Testing at Whittier School, 1890-1920
Authors: CHÁVEZ-GARCÍA MIROSLAVA
Published: May 2007

This article examines the intersections of youth, race, and science in early twentieth-century California. It explores how scientific researchers, reform school administrators, and social reformers at Whittier State School advocated the use of intelligence tests to determine the causes of delinquency. Through the process of testing, they identified a disproportionate number of delinquent boys of color-Mexicans, Mexican Americans, and African Americans-as mentally deficient or "feebleminded." As the evidence reveals, intelligence, race, heredity, and criminality became inextricably linked as the basis for segregating and removing youth of color from the reformatory. The records indicate that, despite officials' recommendations to send feebleminded boys to state hospitals that routinely sterilized their wards, as allowed by a 1909 state law, they sent the majority of youth to the Preston School of Industry, a reform school for older boys. In this instance, expediency in creating a premier institution at Whittier State School took precedence over larger eugenicists designs.
The Demon of Writing: Paperwork, Public Safety, and the Reign of Terror
Authors: Kafka Ben
Published: May 2007

This article investigates the case of a clerk in the Committee of Public Safety who claimed to have rescued more than a thousand men and women from the Terror of 1793–94 by delaying, diverting, and destroying files. It considers the historical and theoretical implications of his actions, arguing that the materiality of paperwork is critical to understanding the powers and failures of the modern state.
Hydration and hydration products of two-phase Portland cement clinker doped with Na2O
Authors: Wistuba S. , Stephan D. , Raudaschl-Sieber G. , Plank J.
Published: May 2007

Alkalis are important minor constituents of ordinary Portland cement clinker. Na2O, in particular, is incorporated into the aluminate phase and alters its crystal structure. For this study, well defined Portland cement clinkers consisting of alite and aluminate doped with different amounts of Na2O were used. Isothermal conduction calorimetry of cements made from this clinker revealed that doping with Na2O activates the initial heat evolution of the clinker during the initial hours. It also influences the main reaction. In situ X-ray diffraction for monitoring cement hydration demonstrates that the dissolution of C3A and gypsum is accelerated by the incorporation of Na2O. The formation of crystalline ettringite and monosulphate during the first few hours of hydration is delayed. After 90 days of hydration, most of the C3A has reacted to monosulphate, detectable by differential scanning calorimetry, scanning electron microscopy and 27Al nuclear magnetic resonance. An increase of the Na2O content brought about less ettringite in the hydrated samples and changed the morphology of monosulphate to thinner and smaller hexagonal plates.
Evaluation of high‐resolution and mobile display systems for digital radiology in dark and bright environments using human and computational observers
Authors: Vogel Rebecca , Saha Anindita , Chakrabarti Kish , Badano Aldo
Published: May 2007

Abstract— As digital display systems replace film traditionally used for reading radiographic images, resource‐intensive acceptance testing must be performed to ensure that quality meets and maintains desired specifications. If machine observers can replace human readers, whose performances are highly variable, the results will be more consistent and less costly. To be effective, however, the automated observers must track human performance. An approach for a model observer, validated with human readers, for the evaluation of the visibility of low‐contrast small targets in high‐resolution and mobile displays under different ambient illumination, will be described. The displays were tested using CDMAM‐like digital phantoms containing disks of varying diameters and contrasts on a flat background. For this task, we find the best indicator of display performance to be the display's ability to represent small luminance contrast, not resolution or pixel size. The results confirm that high‐resolution systems perform better under low illumination while illuminance has a minor impact on the mobile‐display performance. Finally, the results show that the machine observer tracks the performance of human readers. Machine observers with proper validation can replace humans in the acceptance testing procedures, saving the testers both time and money.
Clinical applications for stereoscopic 3‐D displays
Authors: Getty David J. , Green Patrick J.
Published: May 2007

Abstract— Stereoscopic 3‐D digital imaging holds the promise of improving the detection, diagnosis, and treatment of disease as well as enhancing the training and preparation of medical professionals through use of stereoscopic 3‐D displays in concert with the many volumetric visualization techniques/modalities developed in recent years. While so‐called 3‐D graphics have improved the state of computer visualization in general, 3‐D displays make full use of the human‐visual perception, and thus can provide critical insight in complex computer‐generated and video 3‐D data. The stereo 3‐D applications reviewed in this paper include screening of breast cancer and diabetic retinopathy, visualization for minimally invasive surgery, and the teaching of anatomy. Also included is a discussion of ground‐breaking results from a stereo digital mammography clinical trial under way at Emory University.
Process development and accurate low‐cost characterization for OLED sealants by using a calcium test
Authors: Hergert Steffen , Linkor Max , Korny Markus , Fruehauf Norbert
Published: May 2007

Abstract— A calcium measurement setup was built for testing encapsulation especially for OLED applications. This setup is able to measure both reflective and transmissive cells. For the characterization of sealants, a method to compare them with other sealing products will be described. This includes the use of spacers, a homogeneous surface energy, and the geometry of the sealant line. The effects of different geometries will be discussed. The setup was designed to achieve good accuracy at a very reasonable component cost, which will allow other facilities to replicate this setup. Therefore, the construction plan as well as the list of components can be downloaded from our website (Ref. 3).
Die fehlenden Fallstudien | The missing case study
Authors: Hostettler Martin , Pauli Bernhard , Pudack Torsten , Thees Oliver
Published: May 2007

The focus of the 2nd forest economics seminar that took place of 6th/7th June 2005 in Münchenwiler BE was the discussion pertaining to the efficient organisation of forestry management. The theoretical basis for the discussions was the numerous building blocks of new institutional economics. The discussion of four essays and seven co-referents reveal that there is a lack of socially oriented scientific case studies in Switzerland.
Measuring Covalent Binding in Hepatotoxicity
Authors: Devi Sachin S. , Palkar Prajakta S. , Mehendale Harihara M.
Published: May 2007

Many hepatotoxicants like acetaminophen, chloroform, carbon tetrachloride, halothane, and thioacetamide cause hepatotoxicity through covalent binding of their reactive metabolites to proteins. The covalent binding to proteins may lead to dysfunction of critical proteins such as enzymes, transporters, receptors, and regulatory molecules. Because most reactive metabolites covalently bind to tissue macromolecules and tend to be unstable, they can not be isolated, and direct quantitation of the formation of reactive metabolites is not possible. Measuring their covalent binding to proteins offers a convenient way to estimate the amount of reactive metabolite formation. Such estimates have been used to quantify the bioactivation‐based injury due to such hepatotoxicants. There are various methods by which covalent binding may be measured. This unit describes a protocol in which a radiolabeled compound can be utilized to measure covalent binding. Alternate protocols involve immunoblotting and immunohistochemistry. The time and method of measuring covalent binding play an important role in the evaluation.
Managing Immunocompromised Animals
Authors: Donovan John , Brown Patricia
Published: May 2007

This unit describes some commonly used methods for maintaining immunocompromised rodents, specifically mice, to prevent infections from adventitious pathogens. The basic protocol describes the microisolation housing unit, while alternate procedures cover individually ventilated isolator housing, laminar‐flow rack housing, flexible‐film isolator housing, and barrier facility housing.
A New Route to Large‐Scale Synthesis of Silicon Nanowires in Ultrahigh Vacuum
Authors: Xu X. , Wang Y. , Liu Z. , Zhao R.
Published: May 2007

An approach for the large‐scale synthesis of high‐purity silicon nanowires (SiNWs) in ultrahigh vacuum is presented. A mixture of Si and SiO2 is evaporated by an electron beam, and the growth temperature is 700 °C, which is much lower than those used for other oxide‐assisted growths. A new type of single‐crystal SiNWs, with [221] orientation, is thus synthesized. Moreover, it is experimentally demonstrated that SiO intermediates are formed in the process, and the nanowires are obtained via a disproportionation reaction of 2SiO → Si + SiO2. A growth mechanism is proposed and the critical factors for the formation of 1D nanowires are also determined. The approach is particularly compatible with the mature Si‐based technology, and is favorable for device integration and practical applications.
Smart polymeric coatings—recent advances
Authors: Feng W. , Patel S. H. , Young M‐Y. , Zunino J. L. , Xanthos M.
Published: May 2007

There is an ever‐growing number of developments that aim to bring novel functionalities to polymer‐coating systems with nanotechnology being one of them. This article will cover recent advances in the field of smart polymeric structures that are used in protective coatings in terms of stimulus and response, sensing mechanisms, and current or potential applications. Such structures are commonly based on polymers modified through organic or inorganic additives. Emphasis is placed on smart sensors used for detecting the onset of corrosion on polymer coated ferrous and nonferrous substrates. Examples of self‐healing and repair through the action of microcapsules are also presented. © 2007 Wiley Periodicals, Inc. Adv Polym Techn 26:1–13, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20083
Synthesis and properties of transparent thermoplastic segmented polyurethanes
Authors: Chen Po Hung , Yang Yu Fen , Lee Da‐Kong , Lin Ya‐Fen , Wang Hsine‐Hsyan , Tsai Hong‐Bing , Tsai Ruey‐Shi
Published: May 2007

Various segmented polyurethanes with a hard segment content of about 50 wt% were prepared from 4,4′‐diphenylmethane diisocyanate (MDI), a poly(tetramethylene adipate) glycol with an Mn of 2000, and various combinations of aliphatic diols as chain extenders by a one‐shot, hand‐cast bulk polymerization method. The segmented polyurethanes were characterized by gel permeation chromatography (GPC), ultraviolet‐visible spectrometry, differential scanning calorimetry (DSC), and X‐ray diffraction, and their tensile properties and Shore A hardness were determined. The DSC data indicate rather good miscibility between the soft segments and the hard segments that accounts for the good transparency. The incorporation of a small amount of a second chain extender into MDI and 1‐4‐butanediol‐based segmented polyurethanes decreases the crystallinity of the hard segment, thus enhancing the transparency. A segmented polyurethane derived from MDI and 1,6‐hexanediol exhibits better transparency due to its relatively lower crystallinity of the hard segment. © 2007 Wiley Periodicals, Inc. Adv Polym Techn 26:33–40, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20086
Untersuchungen über Gasentladungen in Wasserstoff. II
Authors: Lau Ernst , Reichenheim Otto
Published: May 2007

Die blauen Schichten in einer H2‐Entladung werden dadurch erzeugt, daß in ihnen im wesentlichen nur Elektronengeschwindigkeiten bis zur Ionisation von beigemengten Gasen auftreten. Diese Geschwindigkeiten reichen zur Anregung des Kontinuums des H2, aber nicht für das Viellinienspektrum des H2 aus.

Es wird die Abhängigkeit des Auftretens der blauen Schicht am Anfang der positiven Säule von Beimengungskonzentration, Druck, Stromstärke und Rohrform untersucht.

Die Beobachtungen führten zu einer auch für andere Gase geeigneten Methode zur Messung von Anregungsspannungen. Die Anregungsspannung des Kontinuums und der Einfluß von Fremdgasen auf die spektrale Intensitätsverteilung wird diskutiert.
Über den Wirkungsquerschnitt freier Atomkerne
Authors: Wessel W.
Published: May 2007

Die Wahrscheinlichkeit der Ionen‐ bzw. Atombildung beim Zusammentreffen von Elektronen und Atomkernen, charakterisiert durch einen Wirkungsquerschnitt der Kerne, wird allgemein berechnet und für den Übergang in den Grundzustand, einige angeregte Zustände und ‐ im Sinne der Bohrschen Theorie ‐ sehr exzentrische Bahnen auch explizit angegeben. Die allgemeinen Formeln erlauben, den Wirkungsquerschnitt für sehr große Geschwindigkeiten (> etwa 50 Volt) exakt zu bestimmen; die expliziten genügen, um für kleine Geschwindigkeiten (bis herunter zu etwa 2 Volt) die Wirksamkeit der verschiedenen Bahntypen zu diskutieren und den Gesamtwert auf etwa 10‐20 Proz. festzulegen. Ein Hauptanlaß für die Untersuchung ist, aufzuklären, ob sich dabei Anzeichen für einen von Davis und Barnes neuerdings beobachteten Effekt ergeben. Das ist aber, außer für die Relativgeschwindigkeit Null, nicht der Fall; dieser Effekt würde vielmehr, wenn er sich bewahrheitet, die Quantentheorie nichtstationärer Prozesse vor große Umwandlungen stellen.
Über die Bestimmung der Massenveränderlichkeit des Elektrons an schnellen Kathodenstrahlen
Authors: Starke H. , Nacken M.
Published: May 2007

Es werden die relativen Verfahren zur Bestimmung der Massenveränderung des Elektrons besprochen, bei welchen ohne Ausmessung der Ablenkfelder Strahlen verschiedener Geschwindigkeiten verglichen werden. Tabellarische Übersichten über die gegenseitige Abhängigkeit der Meßgrößen nach der Lorentzschen und Abrahamschen Theorie zeigen, daß in allen Fällen die Genauigkeit der Entscheidung zwischen diesen Theorien mit wachsender Strahlgeschwindigkeit nicht unbegrenzt zunimmt, sondern jeweils einen Höchstwert erreicht. Dieser liegt bei rund 500 kV Strahlspannung.
Die Gleichgewichtsisothermen und ‐isobaren der Kohlenoxyd–Stickstoff–Wasserstoff–Gemische
Authors: Fischer V.
Published: May 2007

Unter Benutzung der Verschoyleschen Versuchswerte werden für das Dreistoffgemisch Kohlenoxyd–Stickstoff–Wasserstoff die Gleichgewichtsisothermen bei −185 und −205° C sowie die Gleichgewichtsisobaren bei 150 und 30 at in einem ebenen orthogonalen Koordinatensystem entwickelt. Aus der allgemeinen Differentialgleichung für den Gleichgewichtszustand zwischen Flüssigkeit und Dampf eines Dreistoffgemisches wird eine Beziehung für die bei den Zustandskurven auftretenden Höchstwerte der Temperatur und des Druckes abgeleitet.
Elektronenterme und Strahlung von Atomen in Kristallen. I. Termaufspaltung und elektrische Dipolstrahlung
Authors: Hellwege H. K.
Published: May 2007

Für alle 27 nicht kubischen Symmetrieklassen werden bestimmt: a) die Elektronenfunktionen nullter Näherung und die zugehörigen Kristallquantenzahlen, b) Zahl und Entartung der Komponenten, in die ein Term vorgegebener Drehimpulsquantenzahl eines freien Atoms beim Einbau in den Kristall aufspaltet, c) Auswahlregeln für Kristallquantenzahlen und Polarisation der Strahlung bei elektrischer Dipolstrahlung.
Die Fluoreszenzanregung von festem und flüssigem Naphthalin, Diphenyl und Phenanthren durch Alphateilchen, schnelle Elektronen und Gammastrahlen. (Mit 11 Abbildungen)
Authors: Herforth Lieselott , Kallmann Hartmut
Published: May 2007

Im folgenden werden Versuche über die Anregung und die Lichtausbeute von festem, kristallinem Naphthalin, Diphenyl und Phenanthren durch Alphateilchen, schnelle Elektronen und Gammastrahlen beschrieben. Ihre physikalische und technische Lichtausbeute relativ zu ZnSAg werden angegeben. Die Absolutausbeuten betragen größenordnungsmäßig: für α‐Teilchen 0,3%, 1,0% und 0,6%; für γ‐Strahlen 5%, 7,5% und 11%. Die Abhängigkeit der Lichtausbeute von der Temperatur wird bis zum Schmelzpunkt herauf bestimmt. Beim Schmelzen geht die Fluoreszenzausbeute auf einen verschwindend kleinen Bruchteil zurück; beim Erstarren der Schmelze geht sie bei allen drei Substanzen wieder in die Höhe, erreicht aber nur etwa den halben ursprünglichen Wert. Pulverisieren der erstarrten Substanz bringt die physikalische Ausbeute wieder auf den alten Wert zurück. Die Gesamtausbeute sowie das Verhalten im flüssigen wie im wieder erstarrten Zustand werden theoretisch diskutiert.
Anwendung der Vierpoltheorie auf die Probleme der optischen Reflexionsminderung, Reflexionsverstärkung und der Interferenzfilter. (Mit 2 Abbildungen)
Authors: Schuster Kurt
Published: May 2007

Die bei der Behandlung von Leitungsvorgängen der Hochfrequenztechnik und Akustik seit langem bewährte Vierpoltheorie kann auch auf die Lichtausbreitung durch eine Folge planparalleler Schichten Anwendung finden. Für senkrechten Lichteinfall werden die Grundgleichungen angegeben. Als Beispiel wird das Problem der Entspiegelung durch eine Doppelschicht dargestellt.
Zur Reflexion von Kugelwellen
Authors: Ott H.
Published: May 2007

Die früheren Berechnungen des Verfassers über die Schmidtsche Kopfwelle beim vertikalen Dipol werden für beliebige Dipolrichtungen erweitert.
Behandlung des Raumrotators im Unterbereich der Laplace‐Transformation
Authors: Päsler Max
Published: May 2007

Als weiterer Beitrag zur Behandlung wellenmechanischer Probleme mittels der Laplace‐Transformation wird in vorliegender Arbeit die Integration der Schrödinger‐Gleichung des Raumrotators im Unterbereich durchgeführt. Man erhält in diesem, wenn man von der Rotator‐Gleichung in der Form (2, 9) ausgeht, eine Differentialgleichung, die sich in zweifacher Weise reduzieren läßt. Beide Fälle werden diskutiert. Dabei kommt im Unterbereich die Tatsache, daß der eine Faktor der Lösung (die zugeordneten Kugelfunktionen) sich als Differentialquotient der Legendreschen Polynome darstellen läßt, unmittelbar zum Ausdruck, wozu es im Oberbereich wohl kein Gegenstück gibt. Die Eigenwerte und Eigenfunktionen des Rotators werden ebenfalls im Unterbereich ermittelt. Es ist auch möglich, die Rotatorgleichung in der Form (2, 6), in welcher die Winkelkoordinate ϑ unabhängige Variable ist, direkt in den Unterbereich zu übertragen, was zu einer Funktionalgleichung führt.
Zur Theorie der unvollständigen Supraleitung
Authors: Koppe Heinz
Published: May 2007

Es wird das Verhalten eines Materials untersucht, welches in einer normalleitenden Grundsubstanz kleine Inseln einer supraleitenden Phase enthält. Man bekommt auf diese Weise einen Ohmschen Leiter mit einer extremen Abhängigkeit der Leitfähigkeit vom Magnetfeld.
Magnetische Pulvermuster auf Kobalt bei höheren Temperaturen Vorläufige Mitteilung
Authors: Andrä Wilfried
Published: May 2007

Mit einer temperaturbeständigen Suspension wird die Veränderung der magnetischen Bereichsstruktur von Kobalt zwischen Zimmertemperatur und 380°C beobachtet.
Über die elektrische Leitfähigkeit fester organischer Isolatoren
Authors: Riehl N.
Published: May 2007

In vorliegender Arbeit wird über Versuche und Überlegungen berichtet, die bereits vor mehr als fünf Jahren angestellt worden sind, aber aus äußeren Gründen bisher nur unvollständig veröffentlicht werden konnten1). Obschon inzwischen einige Arbeiten anderer Autoren zu demselben Thema erschienen sind2), scheint es lohnend, eine eingehende Darstellung unserer damaligen Versuche und der sich daraus ergebenden Konzeption zu bringen.

Die Versuche über elektrische Eigenschaften organischer Isolatoren waren im Rahmen unserer Untersuchungen ursprünglich nicht als Selbstzweck gedacht, sondern nur als Modellversuche zur Frage nach dem Mechanismus der Energie‐ und Ladungswanderung in organischen Systemen (insbesondere den Proteinen)3). Diese Fragestellung brachte es mit sich, daß wir – wie aus dem Folgenden ersichtlich – uns insbesondere für das Verhalten der organischen Isolatoren in Feldern hoher Feldstärke interessiert haben.
Einige Bemerkungen zum Bloch‐Siegert‐Effekt und über Auswirkung desselben auf Doppelfrequenzexperimente
Authors: Lösche A.
Published: May 2007

Es wird der Einfluß eines linearen Störfeldes auf die Resonanzfrequenz eines Kernspin‐Systems berechnet. Daraus ergibt sich eine Möglichkeit, H1 zu messen. Es zeigt sich, daß die Frequenzverschiebung bei der Beurteilung von Doppelfrequenzexperimenten berücksichtigt werden muß.
Wirkungsquerschnitte für die Penning‐Ionisation von H2, N2, Ar, Kr, Xe und Hg durch metastabile Neonatome
Authors: Pfau S. , Rutscher A.
Published: May 2007

Ausgehend von einer verbesserten Diffusionstheorie, die eine quantitativ zufriedenstellende Beschreibung des Säulenplasmas der stromschwachen Neonentladung gestattet, wird diese Theorie für ein Zweikomponenten‐Gasgemisch erweitert. Der Einfluß einer Zumischung auf die Säulencharakteristik einer Entladung ist besonders stark ausgeprägt, wenn der Zusatz mit dem Grundgas den Penning‐Effekt zeigt. Es werden systematische Messungen des Säulengradienten in der Neonentladung bei Zumischung von H2, N2, Ar, Kr, Xe oder Hg durchgeführt und daraus über die Diffusionstheorie die Wirkungsquerschnitte für die Penning‐Ionisation der Zusätze durch die metastabilen Neonatome berechnet.
Die Berechnung von Erwartungswerten im Rahmen der Streutheorie
Authors: Knöll L.
Published: May 2007

Wir entwickeln einen Formalismus, der es gestattet, die zeitliche Änderung der Erwartungswerte von Operatoren im Rahmen der Streutheorie zu berechnen.

Für den Spezialfall der Berechnung von Übergangswahrscheinlichkeiten ergeben sich Zusatzterme gegenüber dem bekannten Ausdruck falls die Zustände |i〉 und |f 〉 nicht orthogonal zueinander sind.

Eine Anwendung auf die Untersuchung nichtlinearer optischer Effekte wird kurz diskutiert.
Die Eindeutigkeit der Ortsobservablen in einer irreduziblen unitären Darstellung bis auf einen Faktor der Galilei‐Gruppe
Authors: Neumann Holger
Published: May 2007

Uniqueness of the Position Observable in an Irreducible Unitary Representation up to a Factor of the Galilei Group.

An elementarary quantum mechanical system with non vanishing mass is characterized by a continuous irreducible unitary representation up to a factor of the Galilei group in Hilbert space. An argument is given concerning the continuous iurreducible unitary representations of the universal covering group of the Euclidean group such that the position observable is uniquely determined by the transformation properties under the representation of the Galilei group.
Quantum Mechanics as a Theory of Relativistic Brownian Motion
Authors: Rylov Yu. A.
Published: May 2007

It is shown that non‐relativistic quantum mechanics can be treated as a kind of relativistic statistical theory which describes a random motion of a classical particle. The theory is relativistic in the sense that for the description of the particle behaviour the relativistic notion of the state is used. This is very important because a statistics is a state calculus and the result depends on the definition of the notion of state.
Der Interferenzeffekt in der magnetischen Kernrelaxation für Vierspin‐Systeme. V
Authors: Blicharski J. S. , Nosel W. , Schneider H.
Published: May 2007

The interference of intramolecular dipole‐dipole interaction and anisotropy of electronic screening in nuclear magnetic relaxation is taken into account for systems containing four identical nuclei of spin 1/2 located at the corners of a tetrahedral, a square and a rectangle. The influence of spinrotational interaction is also considered. The results, presented in the paper show that, due to the interference effect, a significant deviation of a pure exponential time dependence of nuclear magnetization in some special cases may appear.
On the Role of the Results Obtained by the Analytical Theory of Elementary Particles
Authors: Phát Trân HŨU
Published: May 2007

To prove that it is possible to obtain many results (such as the asymptotic relations of Pameranchuk type, Froissart inequality, Martin theorem, etc.) of the analytical theory of elementary particles in any theory where the ordinary analyticity of dispersion amplitude is replaced by a certain generalized analyticity (such as the p‐analyticity of Poloji, the generalized analyticity of Vekua). Hence we cannot consider these results as criteria for the validity of the analyticity at high energies. Therefore, in order to check the analyticity we ought to establish the relations which can not be deduced from any generalized analyticity, except ordinary analyticity.
Zur Konstanz der Teilchenzahlen in der allgemeinen Relativitätstheorie
Authors: Treder H.‐J.
Published: May 2007

This paper suggests that the “spontaneous creation of matter in strong gravitation fields” – which is asserted in some papers – may be a result of an inconsistent approximation for the simultaneous systems of Einstein field equations and of matter field equations.

Firstly we shall remark that Einstein's dynamical equation is not only the consequence of the Einstein field equations (via Bianchi identity) but also the consequence of the relativistic matter field equations and of the weak principle of equivalence. Therefore, for all discussions we must start from the dynamical equation and from the conservation laws of charges.

Secondly, we find a formal inhomogeneous dynamical equation for the matter tensor by working in a background‐field approximation. But, this inhomogenity vanishes according to the matter field equations.

Thirdly, we discuss the properties in an evolution‐cosmos. In such cosmos a law of conformal conservation of energy is fulfilled. From this conservation law results that the energy is a continuous function of the gauge of time. Such continuous dependence involves the constance of discrete numbers according to the well known argument of Planck.
Fluktuationen beim optischen parametrischen Oszillator
Authors: Brunner W. , Paul H. , Bandilla A.
Published: May 2007

In a heuristic manner – analogous to the procedure known from laser theory – the correlation functions for the fluctuation operators (Langevin forces) connected with the spontaneous decay of pump photons into both signal and idler photons as well as the loss mechanism for the radiation are calculated.
Optische Übergänge in hochdotierten und gemischten Halbleitern: Die verallgemeinerte Bloch‐Matrix
Authors: Unger K.
Published: May 2007

To treat fluctuating perturbation potentials in semiconductors, it is necessary to take quantum corrections to the Thomas‐Fermi approximation into account. A generalization of the Bloch matrix, valid for arbitrary degrees of degeneracy, is used to handle these quantum corrections. The generalized Bloch equation and the results of a treatment of optical transitions in high‐doped semiconductors with this method are given. The concept of effective band edges is shown to be useful for the problem on hand.
Townsend‐Koeffizient α für Alkoholdämpfe, Luft und Argon
Authors: Fiedler O. , Kunze P. , Trommer S.
Published: May 2007

Measurements of the first Townsend coefficient for the vapours of CH3OH, C2H5OH, C3H7OH(n), C3H7OH(iso) are described. The experimental arrangement is tested by measuring the known values of air and argon.
A Rather General Variational Principle for Purely Dissipative Non‐Stationary Processes
Authors: Lambermont J. , Lebon G.
Published: May 2007

A general variational principle concerning non‐stationary purely dissipative phenomena, obeying ONSAGER's reciprocal relations, is presented. The principle expresses that the variation of the sum of the total entropy production and the time derivative of the MASSIEU function is equal to zero. It is shown that the EULER‐LAGRANGE equations corresponding to arbitrary variations of the state variables yield the conservation laws. Other general criteria for non‐stationary processes have been given by GLANSDORFF‐PRIGOGINE and GYARMATI. They are compared with our principle.

Two illustrative examples are considered: coupled heat and electrical conduction in an isotropic medium and chemical reactions coupled with diffusion of matter and heat conduction in a multi‐component fluid.