bluuebunny/crossref_metadata_2025 huggingface dataset:
The relationship between self‐perception of physical attractiveness and sexual bullying in early adolescence
Authors: Cunningham Nancy J. , Taylor Matthew , Whitten Michael E. , Hardesty Patrick H. , Eder Katheryn , DeLaney Nancy
Published: July 2010

The relationship between self‐perception of physical attractiveness and four measures of sexual bullying behavior (victimization, perpetration, having friends who sexually bully, and observation of sexual bullying among peers at school) was examined in a sample of 396 middle school age students. Students who perceived themselves to be more physically attractive than their peers reported sexually bullying others more, being sexually bullied by others more, observing more sexual bullying, and having more friends who sexually bully others than did students who perceived themselves as average looking. In addition, males who perceived themselves to be less physically attractive than their peers reported being victimized more and reported observing more sexual bullying in the school environment. These findings highlight the importance of physical attractiveness in the early initiation of sexual harassment. Implications for future research and interventions with early adolescents are discussed. Aggr. Behav. 36:271–281, 2010. © 2010 Wiley‐Liss, Inc.
Narcissism and unprovoked aggression
Authors: Reidy Dennis E. , Foster Joshua D. , Zeichner Amos
Published: July 2010

It is widely accepted that narcissists become aggressive when they experience ego‐threat. However, there is surprisingly little empirical research on the relationship between narcissism and aggression. Equivocal findings suggest that aggression in narcissists either occurs only in response to provocation, or regardless of provocation. One‐hundred and thirty‐seven collegiate men completed the Narcissistic Personality Inventory followed by a sham aggression paradigm, which afforded them the opportunity shock, or refrain entirely from shocking an ostensible opponent confederate. Participants were identified as “unprovoked aggressors,” “retaliatory aggressors,” or “nonaggressors” contingent on when and if they chose to administer electrical shocks to the confederate. Results indicated that participants who were high on narcissistic traits were more likely to be unprovoked aggressors than their low narcissism counterparts. Results are discussed in relation to threatened egotism theory and call for more research on narcissism, aggression, and the moderating effect of provocation. Aggr. Behav. 36:414–422, 2010. © 2010 Wiley‐Liss, Inc.
High‐Resolution Scanning Near‐Field Optical Lithography of Conjugated Polymers
Authors: Credgington Daniel , Fenwick Oliver , Charas Ana , Morgado Jorge , Suhling Klaus , Cacialli Franco
Published: July 2010

The fabrication of high‐resolution nanostructures in both poly(p‐phenylene vinylene), PPV, and a crosslinkable derivative of poly(9,9′‐dioctylfluorene), F8, using scanning near‐field optical lithography, is reported. The ability to draw complex, reproducible structures with 65000 pixels and lateral resolution below 60 nm (< λ/5) is demonstrated over areas up to 20 μm × 20 μm. Patterning on length‐scales of this order is desirable for realizing applications both in organic nanoelectronics and nanophotonics. The technique is based on the site‐selective insolubilization of a precursor polymer under exposure to the confined optical field present at the tip of an apertured near‐field optical fiber probe. In the case of PPV, a leaving‐group reaction is utilized to achieve insolubilization, whereas the polyfluorene is insolubilized using a photoacid initiator to create a crosslinked network in situ. For PPV, resolubilization of the features is observed at high exposure energies. This is not seen for the crosslinked F8 derivative, r‐F8Ox, allowing us to pattern structures up to 200 nm in height.
Silver Surface Iodination for Enhancing the Conductivity of Conductive Composites
Authors: Yang Cheng , Xie Yu‐Tao , Yuen Matthew Ming‐Fai , Xu Bing , Gao Bo , Xiong Xiaomin , Wong C. P.
Published: July 2010

The electrical conductivity of a silver microflake‐filled conductive composites is dramatically improved after a filler surface treatment. By a simple iodine solution treatment, nonstoichiometric silver/silver iodide nanoislands form on the silver filler surface. Evidence of the decrease of surface silver oxide species is provided by TOF‐SIMS and the redox property of the nanoclusters is studied using cyclic voltammetry and TOF‐SIMS depth profile analyses. The redox property of the nanoclusters on silver flakes helps enhance the electrical conductivity of the conductive composites. The electrical resistivity of the improved conductive composites is measured by four‐point probe method; the reliability of the printed thin film resistors is evaluated by both the 85 °C/85% relative humidity moisture exposure and the −40 ∼ 125 °C thermal cycling exposure. The conductive composite printed radio frequency identification (RFID) antennas with 27.5 wt% of the modified silver flake content show comparable performance in the RFID tag read range versus copper foil antennas, and better than those commercial conductive adhesives that require much higher silver content (i.e., 80 wt%). This work suggests that a surface chemistry method can significantly reduce the percolation threshold of the loading level of the silver flakes and improve the electrical conductivity of an important printed electronic passive component.
Microstructural Characterization and Charge Transport in Thin Films of Conjugated Polymers
Authors: Salleo Alberto , Kline R. Joseph , DeLongchamp Dean M. , Chabinyc Michael L.
Published: July 2010

The performance of semiconducting polymers has been steadily increasing in the last 20 years. Improved control over the microstructure of these materials and a deeper understanding of how the microstructure affects charge transport are partially responsible for such trend. The development and widespread use of techniques that allow to characterize the microstructure of semiconducting polymers is therefore instrumental for the advance of these materials. This article is a review of the characterization techniques that provide information used to enhance the understanding of structure/property relationships in semiconducting polymers. In particular, the applications of optical and X‐ray spectroscopy, X‐ray diffraction, and scanning probe techniques in this context are described.
Ruthenium ONO‐Type Pincer Complex: Synthesis, Structural Characterization, and Catalysis
Authors: Zhang Yao , Li Xingwei , Hong Soon Hyeok
Published: July 2010

A novel nitrone‐based pincer ligand was developed by a single‐step synthesis from N‐(tert‐butyl)hydroxylamine acetate and 2,6‐pyridinedicarboxaldehyde. The developed ligand allowed us to synthesize a cationic ruthenium pincer complex. A distorted octahedral coordination environment around the ruthenium center was observed. The complex showed excellent catalytic activity in transfer hydrogenation reactions with turnover numbers up to 590,000.
Serum free light chain analysis
Authors: Davids Matthew S. , Murali Mandakolathur R. , Kuter David J.
Published: July 2010

In a variety of hematologic malignancies, immunoglobulin light chains (LC) are overproduced clonally and circulate without being linked by disulphide bonds to the immunoglobulin heavy chain. The recent development of a robust assay known as κ and λ “free” LC (FLC) to quantify the levels of these unbound LC in the serum, and thereby determine their ratio, has led to an explosion of studies that demonstrate its utility in a wide range of hematologic disorders. This article summarizes laboratory testing for serum FLC, with a particular focus on clinical applications for the test. Am. J. Hematol., 2010. © 2010 Wiley‐Liss, Inc.
Ape behavior in two alternating environments: comparing exhibit and short‐term holding areas
Authors: Ross S.R. , Wagner K.E. , Schapiro S.J. , Hau J.
Published: July 2010

In many facilities, primates are voluntarily transferred between different enclosures on a daily basis to facilitate animal husbandry and exhibit maintenance. This procedure is particularly relevant in the management of great apes living in zoos, where the requirements of functional management must be balanced with the desire to maintain enriching and naturalistic exhibit enclosures that benefit ape residents and attract the visiting public. In these settings, examinations of ape behavior and welfare typically focus exclusively on activity in the primary exhibit area. However, physical, social and sensory experiences unique to each area may shape different patterns of behavior. In the current study, zoo‐living chimpanzees and gorillas were moved each day from exhibit areas to off‐exhibit holding areas for a short duration as a part of regular management procedures. Behavioral data indicated species‐specific reactions to the holding area, including increased aggression and self‐directed behavior by chimpanzees and increased activity and prosocial behavior among gorilla subjects. Both species showed more feeding‐foraging behavior while in the exhibit enclosure. Results suggest that holding areas may not meet all behavior needs of captive great apes and demonstrate the importance of including all components of the captive enclosure in comprehensive analyses of great ape behavior and welfare. Am. J. Primatol. 72:951–959, 2010. © 2010 Wiley‐Liss, Inc.
Mated pairs of owl monkeys (Aotus nancymaae) exhibit sex differences in response to unfamiliar male and female conspecifics
Authors: Wolovich Christy K. , Evans Sian , Green Steven M.
Published: July 2010

In socially monogamous species, mate‐guarding could be a reproductive strategy that benefits both males and females, especially when males contribute to parental care. By actively guarding mates, males may reduce their chances of being cuckolded, whereas females that mate‐guard may reduce the likelihood that their mates will desert them or acquire additional mates, and hence limit or reduce paternal care of offspring. Owl monkeys (Aotus spp.) are socially monogamous with biparental care of young and, hence, potential beneficiaries of mate‐guarding. We presented mated pairs of captive owl monkeys (A. nancymaae) with unfamiliar male and female conspecifics, to determine if either member of the pair exhibits intraspecific aggression toward an intruder or stays close to its mate, behaviors indicative of mate‐guarding. Male mates were more responsible for the maintenance of close proximity between mates than females. Male mates also exhibited elevated levels of behavior that signify arousal when presented with a male conspecific. These responses by mated male owl monkeys are consistent with patterns that may help prevent cuckoldry. Am. J. Primatol. 72:942–950, 2010. © 2010 Wiley‐Liss, Inc.
A three‐year prospective longitudinal cohort study of medical students' attitudes toward anatomy teaching and their career aspirations
Authors: Bhangu Aneel , Boutefnouchet Tarek , Yong Xu , Abrahams Peter , Joplin Ruth
Published: July 2010

Today's medical students are faced with numerous learning needs. Continuously developing curricula have reduced time for basic science subjects such as anatomy. This study aimed to determine the students' views on the relevance of anatomy teaching, anatomical knowledge, and the effect these have on their career choices. A Likert scale questionnaire was distributed to second year medical students [response rate 91% (n = 292/320)]. The same questionnaire was subsequently distributed to the cohort three years later when they were final year students [response rate 37% (n = 146/392)]. Students in both the cohorts of study agreed strongly that clinically correlated anatomical teaching was relevant to clinical practice (92% and 86% of second and final year respondents, respectively) and helped them during their clinical placements (73% and 92%, respectively). Only 28% of the second year and 31% of the final year students agreed that their anatomy teaching prepared them to interpret clinical images (P = 0.269). Only 14% of the final year students felt confident in their knowledge of anatomy. Of the final year students, 30% felt that they had enough opportunity to scrub in the operating room. Nearly half of those students who would consider surgery as a career (19%) think that they will eventually become surgeons (11%). This data suggests that modern anatomy curriculum should focus on clinical correlations and clinical image interpretation. Students would value more opportunities to participate in surgeries. Vertical integration of anatomy teaching throughout the full medical course may be useful. Anat Sci Educ. © 2010 American Association of Anatomists.
An Evaluation of Index Medicus and MEDLARS in the Field of Ophthalmology
Authors: Virgo Julie A.
Published: July 2010

An evaluation of the performance of Index Medicus and MEDLARS in the field of ophthalmology is presented, using data generated by a separate study. MEDLARS performance figures gave a screened precision ratio of 54% and a recall ratio of 42%. Over the same set of questions Index Medicus had a screened precision ratio of 53 % and a recall ratio of 46%. Results for Index Medicus alone over a larger set of questions gave a 73 % screened precision ratio and a 47% recall ratio. A random sample of MEDLARS and Index Medicus precision and recall failures showed that most of the Index Medicus recall failures resulted from manual searcher omissions. The major causes of MEDLARS precision failures were inadequate indexing terminology to express concepts and attempts at providing too exhaustive a search.
Education in Information Science
Authors: Belzer Jack
Published: July 2010

Information science encompasses many notions, ideas, concepts, principles, and techniques. It relates symbols, words, and language to the world about us. It permits us to hypothesize about the structure of the universe, forecast about future events, and extend knowledge. Information is dynamic, and its rate of growth demands of us that scientific methods and technology be applied to deal with this problem or it will be virtually impossible to meet the demands it imposes on our society. To meet this challenge, trained professional personnel are needed. The universities have the responsibility of preparing such manpower. The career opportunities exist for information scientists, information systems analysts and designers, and professional staff in information transfer, and the demands for experts are increasing. The important question is, are our programs and our curricula in the universities accomplishing this mission? The probability is that many of these programs could be improved substantially. It is our responsibility to examine these programs and analyze this data, which should indicate to us the degree to which our mission is being accomplished. We should be able to provide guidelines that would be useful to individual institutions in reviewing their own programs.
Promising Developments in Computer‐Assisted Instruction
Authors: Jerman Max
Published: July 2010

The work in computer‐assisted instruction conducted at Stanford is reviewed in the context of developmental stages through which the CAI programs have passed, and the next step in the evolution of these programs is discussed.

Areas that might be well suited to computer‐assisted instruction also are mentioned, and systems now moving in these directions are described.

Our experiences in teacher training and coordinating computer‐assisted instruction with classroom instruction are reviewed.
Overlap Among the Journal Articles Selected for Coverage by BIOSIS, CAS, and Ei
Authors: Wood James L. , Flanagan Carolyn , Kennedy H. Edward
Published: July 2010

Of 14, 592 primary journals being collectively monitored by the BioSciences Information Service of Biological Abstracts (BIOSIS), the Chemical Abstracts Service (CAS), and Engineering Index, Inc. (Ei) on 1 May 1970, only 4081 were being monitored by two or more of the services.

The extent to which all three or any two of these services select the same journal article for coverage was determined by examining each service's selection records for the July 1969–June 1970 issues of these 4081 overlap journals. The maximum possible journal article overlap among BIOSIS, CAS and Ei was found to be 822 articles and between BIOSIS and Ei, 1428 articles. The journal article overlap between BIOSIS and CAS was found to be 48, 856 articles and between CAS and Ei, 21, 583 articles.
Development of an Integrated Energy Vocabulary and the Possibilities for On‐line Subject Switching
Authors: Niehoff R. T.
Published: July 2010

This paper describes the development of an integrated vocabulary of energy terminology and it explores the potential for a fully developed energy vocabulary conversion guide. Eleven vocabularies were analyzed and integrated: AIP, CA, API, GA, INIS, TEST, GEOR, El, PA, DDC, and NASA.

The following major concepts were considered within the scope: energy sources (fuels); derived products; exploration, production and processing; energy conversion; energy transportation, transmission and distribution; energy consumption, utilization, and conservation; power generation; energy storage; energy policy and legislation; environmental impacts; transportation modes (land, air, sea); propulsion systems; consuming sectors and economics; and international supply and consumption.

The methodology consisted of 1) establishing term selection criteria, 2) analyzing individual system vocabularies for energy‐related terms, 3) processing energy subsets and 4) reviewing the integrated product and generating a final vocabulary.

Three broad problem areas were identified during the study: 1) energy definition, 2) analyst viewpoint variances, 3) thesaurus format/convention variances. The conceptualization, identification, and selection of energy terms was especially difficult in several subject disciplines, including such areas as engineering materials, mathematics, electronics, explosives, psychology and other social sciences. Five types of synonym construction were encountered.

It was concluded that vocabulary conversion, which permits subject switching, offers some degree of inter‐system compatibility. Conversion is the ability to retrieve all documents on a given subject from all available (and appropriate) data bases with a single query. When coupled with development of a standard system protocol, full information‐resource utilization will be possible.

A prototype conversion guide (synonym table) was constructed for further study. One of the significant findings was that, without any additional intellectual efforts, conversion can be increased from 28 percent (exact match only) to 46 percent using exact match plus singular‐plural equivalencies, plus synonym expansion.
Knowledge Space: A Conceptual Basis for the Organization of Knowledge
Authors: Meincke Peter P. M. , Atherton Pauline
Published: July 2010

We propose a new conceptual basis for visualizing the organization of information, or knowledge, which differentiates between the concept “vectors” for a field of knowledge represented in a multidimensional space, and the state “vectors” for a person based on his understanding of these concepts, and the representational “vectors” for information items which might be in a retrieval system which covers a sub space of knowledge. This accommodates the notion of search volume in which the user of a retrieval system can expand or reduce the subspace he searches for relevant information items which have representational vectors with components on basic concept vectors similar to his state vector. The benefits of such a new conceptual framework are explored in this article.
Comparison of Printed Bibliographic Descriptions Distributed by BIOSIS, CAS, and Ei
Authors: Larson Julian R. , Bernhard Gail A. , Padin Mary Ellen
Published: July 2010

Printed bibliographic descriptions of journal articles cited by BioSciences Information Service of Biological Abstracts (SIOSIS), Chemical Abstracts Service (CAS), and Engineering Index (Ei) were compared to identify similarities and differences in form, format and data content.

Collectively, the three services use 15 different bibliographic data elements, five to provide a description of the journal issue and ten to describe the article. All three services used eight of the 15 data elements. Of the remaining seven data elements, four were used by two of the three services and three were used by only one of the services.

The differences in the content of the three services' printed bibliographic descriptions do not adversely affect the user's ability to identify the cited publications.
A Generalized Flowchart for the Use of ORBIT® and Other On‐line Interactive Bibliographic Search Systems
Authors: Morrow Deanna I.
Published: July 2010

A generalized flowchart, designed to aid the new or occasional user of an on‐line interactive bibliographic search system, is presented. It is intended to answer the question: “What do I do now?”
A Work Study of the Review Production Process
Authors: Swanson Rowena Weiss
Published: July 2010

This Communication presents experiential data on the work activities, performance times and costs involved in the preparation of an analytic review for the Annual Review of Information Science and Technology.
Collection Overlap as a Function of Library Size: A Comparison of American and Canadian Public Libraries
Authors: Davis Charles H. , Shaw Debora
Published: July 2010

Random samples of monographic materials from American and Canadian public libraries were matched with the collections of similar libraries of different sizes. Materials with a publication date earlier than 1970 were excluded in order to reduce the sample size, to minimize the effects of comparing older and newer libraries, and to increase the relevance of the findings for resource sharing through contemporary on‐line computer‐based networks. A strong positive correlation appears to exist between percentage find rate and target library size, with regression analysis suggesting linearity over a wide range of collection sizes.
A Reliability Theoretic Construct for Assessing Information Flow in Networks
Authors: Sullo Pasquale , Wallace William A. , Triscari Thomas , Chazen Cathy A. , Davis James F.
Published: July 2010

A reliability theoretic construct is proposed for conceptualizing the process of information flow. It focuses on information produced to satisfy specified purposes or to achieve preconceived objectives. Furthermore, the model incorporates explicitly the concept of an information producer contemplating a choice of action in an uncertain environment. The resulting models are therefore prescriptive in nature. The usefulness of this construct is illustrated by a case analysis of the effectiveness of natural resource data products in land‐use decision making. Measures of system reliability of the information flow network are determined and sensitivity analyses performed. Numerical examples are presented and discussed. The prescriptive nature of this approach permits use of its results to indicate how a data producer can increase the effectiveness of documents by identifying the information flow network, assessing the reliability of each component in the network, finding measures of system reliability, and performing sensitivity analyses to identify the critical components of the system. The result is a closer congruence between the objectives of the data producer and the requirements of users.
Two Models for Predicting Subject Circulation: A Contribution to the Allocation Problem
Authors: Mcgrath William E.
Published: July 2010

It is shown that different sets of variables can account for nearly equal amounts of variance when predicting book circulation by subject. Proportion of variance (R2) for two basic models containing various combinations of 21 variables were tested. The first, called the shelf list model, treated the number of library books, whose subjects match those of academic departments, as a control variable. As such, it accounted for 6Wo of the variance, thus entering the equation first. With this model, four separate significant sets emerged, each accounting for approximately thb same amount of variance (10%). They were (1) number of faculty, hardhoft, masters enrollments; (2) masters enrollments, upper‐level majors, hardhoft; (3) credit hours X total enrollments, hardhoft; (41 tipper‐level majors, total majors, enrollments lower. In the second, shelf list was constrained by defining the dependent variable as the proportion of shelf list circulated. With this model, three separate significant sets emerged. These were (5) masters enrollments and hardhoft (20% variance); (6) hard‐soft and Ph.D. program (16%); (7) upper‐level majors, and credit hours × total majors (15%). In each of the tests, no other variables were significant. Of the 21 variables, 10 did not appear in any of the 7 sets. Any of the seven sets could be used in an allocation formula. The deciding criterion for choosing a set may depend on the convenience of collecting data for each of the variables in the set.
Relevance
Authors: Bookstein Abraham
Published: July 2010

The concept of relevance is fundamental to information retrieval, yet the literature shows a diversity of meaning for this term. It is suggested that for this term to be of use in discussions of information retrieval systems, the term should be tied as directly as possible to the goals and operations of these systems, and one such definition is suggested. Other uses are examined in this light. Two models of information retrieval systems—one created by Maron and Kuhns, the other by Swets—in which the notion of relevance is central, are examined; the use of the concept in each is analyzed and the systems are related to each other.
National Network of Information in Poland
Authors: Nitecki Joseph Z.
Published: July 2010

This article attempts to reconstruct, from the material available to the author, the concept of the national system of scientific, technical, and organizational information in Poland. A new approach to the system was formally introduced in 1974 and is now a subject of extensive debate among Polish librarians and information specialists. The network might be of interest to some Western readers for its unique scope, and for its professional and political implications.
A Test of Buck's Prime Number Coding Scheme
Authors: Cleveland Ana Divino , Cleveland Donald B.
Published: July 2010

An experiment was carried out to study the effect of coding, as an independent variable, on the information retrieval process. A simple prime number coding scheme was utilized in conjunction with Goffman's indirect method file structuring and searching technique. The results demonstrated that a code, in itself, can affect retrieval. It introduces a noticeable variable into the process. Generally, coding has been considered a minor element, but clearly much more needs to be learned about how codes interact with the other functions in the retrieval system.
On the Value of Information
Authors: Ozog Stanley
Published: July 2010

Based on the definition of information acquisition as the reduction in uncertainty, the concept of ignorance is defined as the state of uncertainty. Two basic types of ignorance are then defined as substitutes for information: guessing and belief. Two types of frequency distribution are presented as the most general dichotomy that can be applied to all possible types of frequency distribution and from them two limits are deduced between which all types of frequency distribution can be placed. Using games of chance—roulette and horse racing—as representatives of two basic types of frequency distribution, the comparison is presented of different results that can be theoretically obtained by the informed, the guessing, and the belief approaches. The value of information is a function of the type of frequency distribution of data that form its contents. The limits established for the types of frequency distribution are also boundary conditions for information value from nil to some finite number that depends also on the number of alternatives involved in case of a discrete set, and on range size, accuracy of measurement, and its precision in case of continuous parameters.
Characteristics of a Literature as Predictors of Relatedness Between Cited and Citing Works
Authors: Bonzi Susan
Published: July 2010

A preliminary investigation was conducted to explore which characteristics of citing and cited works may aid in determining relatedness between documents. Thirteen variables were tested on 31 library/information science articles containing nearly 500 citations. Analysis indicates that source of cited work, source of citing work, number of times a work is cited in text, and type of citing article show promise of predicting relatedness between citing and cited works.
The Use of Discriminant Analysis to Select Content‐Bearing Words
Authors: Dillon Martin , Federhart Peggy
Published: July 2010

This article presents a method for identifying good indexing terms from frequently occurring stems. The method uses discriminant analysis to distinguish terms that refer to topics from general terms that do not refer to topics. The steps in the method are the selection of discriminating variables, the calibration of predefined groups and the derivation of discriminant functions from them, and the classification of a second, unknown set of terms and its evaluation. The method is tested by applying it to the Harris Survey Question database, which covers 121 different surveys and includes the text of over 12, 000 Individual questions. The evaluation demonstrates the success of the method.
Marketing Research in the Scientific and Technical Information Services Industry: Development and Future Directions
Authors: Thomas Robert J.
Published: July 2010

The general availability of government‐sponsored studies on scientific and technical information (STI) provides an opportunity to trace the development of “marketing research” in a specific industry. A review of this research tradition revealed two major orientations; a series of “user”‐oriented studies, followed by “systems”‐oriented studies. It is suggested that traditional STI user studies may have produced “myopic” research results, and systems studies may have produced “macropic” research results for STI policy decisions. An emerging “managerial” orientation is identified which espouses the definition of a more meaningful unit of analysis as the focus of future research efforts.
Matched Case‐Control Studies in Citation Analysis
Authors: Peritz Bluma C.
Published: July 2010

The need to control for the effect of confounding variables is central to empirical research in many disciplines. In small‐scale studies it is often useful to do this at the designing stage (rather than in the analysis) by means of “case”‐“control” matching. It is suggested that this applies to citation studies as well. As an illustration the citation counts of papers by Israeli economists are compared with those of matched controls by American authors. This illustration highlights methodological and technical issues. It also serves to point out how small‐scale studies can generate interesting hypotheses.
Photo‐Hydrogen‐Evolving Molecular Catalysts Consisting of Polypyridyl Ruthenium(II) Photosensitizers and Platinum(II) Catalysts: Insights into the Reaction Mechanism
Authors: Ozawa Hironobu , Kobayashi Masayuki , Balan Bijitha , Masaoka Shigeyuki , Sakai Ken
Published: July 2010

The mechanism of photoinduced hydrogen evolution from water driven by the first photo‐hydrogen‐evolving molecular catalyst (1), given by a coupling of [Ru(bpy)2(5‐amino‐phen)]2+ and [PtCl2(4,4′‐dicarboxy‐bpy)] (bpy=2,2′‐bipyridine, phen=1,10‐phenanthroline), was investigated in detail. The H2 evolution rate was found to obey Michaelis–Menten enzymatic kinetics with regard to the concentration of EDTA (ethylenediamine tetra‐acetic acid disodium salt, sacrificial electron donor), which indicates that an ion‐pair formation between the dicationic 1 and the dianionic form of EDTA (pH 5) is a key step leading to H2 formation. A 2:1 coupling product of 1 and ethylenediamine (i.e., a {RuII2PtII2} complex 2) was found to show significantly higher photo‐hydrogen‐evolving (PHE) activity than 1, which revealed the validity of the bimolecular activation proposed in our previous study. The PHE activity of 2 was also observed to be linear to the concentration of 2, which indicates that H2 formation through the intermolecular path competes with the intramolecular path. Molecular orbital diagrams, conformational features, and Pt⋅⋅⋅H(water or acetic acid) hydrogen bonds were characterized by DFT calculations.
Organocatalytic Stereoselective α‐Alkylation of Aldehydes with Stable Carbocations
Authors: Benfatti Fides , Benedetto Elena , Cozzi Pier Giorgio
Published: July 2010

The organocatalytic stereoselective alkylation of aldehydes is carried out with the four stable carbocations 1, 2, 3, 4 in the presence of a catalytic amount (20 mol%) of MacMillan imidazolidinones 5, 6. In all reactions, lutidine was used as a base. The alkylation reactions are investigated at different temperatures with linear and branched aldehydes. In the case of carbocation tropylium fluoroborate, an interesting reversal of alkylation product configuration was observed, which is driven by entropic effects in the reaction. The absolute configuration of the products obtained is determined by chemical correlation and found to be in general agreement with the model proposed by MacMillan to justify the stereoselectivity obtained in the reactions promoted by catalysts of type 5, 6.
Unit root testing in the presence of ARFIMA–GARCH errors
Authors: Wang Gaowen
Published: July 2010

We consider asymptotic behavior of self‐normalized sums of autoregressive fractionally integrated moving average (ARFIMA) processes whose innovations are GARCH errors. The asymptotic distribution of the sums is derived under very mild conditions. Applications to unit root tests with ARFIMA–GARCH errors are discussed. It is shown that even when the errors exhibit both long‐range dependence and heavy‐tailed conditional heteroscedasticity, the asymptotic distributions of the Dickey–Fuller ρ‐type tests are functionals of standard Brownian motion rather than those of fractional Brownian motions. Some Monte Carlo simulations are provided to illustrate the finite sample properties of two of the tests. Copyright © 2010 John Wiley & Sons, Ltd.
Die streifende Feuerkugel vom 14. Januar 1965
Authors: Oleak H.
Published: July 2010

Es wird über den seltenen Fall einer sehr hellen und streifend die Atmosphäre durchziehenden Feuerkugel berichtet. Aus rund tausend Augenzeugenberichten wurden folgende Bahndaten abgeleitet: Das Meteor überquerte den Ort Gr. in einer Höhe von 80 6 km aus dem Azimut 74 1 (ONO) kommend. Die Bahnneigung gegen die Horizontale betrug 3 1, in Bewegungsrichtung nach außen weisend. Die geozentrische Geschwindigkeit lag wahrscheinlich zwischen 15 und 20 km/s. Der Radiant liegt fast in der Ekliptik (‐2β6); der Körper überholte die Erde aus geringerer Sonnenentfernung kommend und gehört wahrscheinlich dem Asteroidengürtel an (a1.7 AE). Die Größe des Körpers wurde aus seiner Helligkeit auf ein bis fünf Meter abgeschätzt.
Suche nach sonnennahen roten Zwergsternen und räumliche Dichte der roten Riesen
Authors: Klare G. , Schaifers K.
Published: July 2010

Es wird eine kombinierte Spektral‐ und Eigenbewegungsdurchmusterung beschrieben, die das Auffinden sonnennaher roter Zwergsterne zum Ziel hatte. In dem untersuchten Feld (2h α) zeigten von 1571 als späte Spektraltypen klassifizierten Sternen 53 im Blinkkomparator eine Eigenbewegung, aus der mit Hilfe von Eigenbewegungskriterien zunächst eine obere Grenze der Leuchtkraft und schließlich Entfernungen angegeben werden. Diese Zahlen entsprechen den Erwartungen auf Grund von Abschätzungen. Wegen ihrer kleinen Eigenbewegungen darf angenommen werden, daß es sich bei den restlichen 1518 Objekten um Riesen handelt. Aus dieser Gruppe wurden 452 späte K‐ bis M‐Sterne abgetrennt. Aus der Verteilung ihrer scheinbaren Helligkeiten folgt für diese Sterne eine Schichtdicke 2 z = 37 pc senkrecht zur galaktischen Ebene und eine räumliche Dichte D0 = 46. 10‐6 Sterne pro pc3 in der galaktischen Ebene.
Die Bahnneigung spektroskopischer Doppelsterne mit Ap‐Komponenten und die axiale Rotationsgeschwindigkeit der Ap‐Sterne
Authors: Schöneich W.
Published: July 2010

Für 13 spektroskopische Doppelsternsysteme mit Ap‐Komponenten wurden die minimalen Bahnneigungswinkel abgeschätzt. Unter der Annahme, daß die Richtungen der Bahn‐ und Rotationsachsen zusammenfallen, erhält man Neigungswinkel, die für den größten Teil der Systeme viel zu groß sind, als daß die geringen beobachteten Rotationsgeschwindigkeiten allein durch die „pole‐on”︁‐Hypothese erklärt werden könnten. Daraus wird der Schluß gezogen, daß die Rotationsgeschwindigkeiten der Ap‐Sterne wirklich kleiner sind als die normaler A‐Sterne.
Die Intensitätsverteilung im Spektrum des Kometen AREND‐ROLAND (1957 III)
Authors: Pflug K.
Published: July 2010

Spektralphotometrische Messungen der Intensitätsverteilung im Spektrum des Kometen Arend‐R ergeben eine merkliche Variation der Farbe des gestreuten Sonnenlichtes mit dem Streuwinkel. Während für Streuwinkel um 70 keine Verfärbung feststellbar ist, zeigen Beobachtungen bis in Streuwinkel von 130 eine zunehmende Rötung (relativer spektralphotometrischer Gradient in bezug auf die Sonne bis auf 0.5 ansteigend). Die Übereinstimmung mit Beobachtungen anderer Autoren ist gut.
Bemerkungen zur räumlichen Häufigkeit der weißen Zwerge in der Sonnenumgebung
Authors: Gürtler J. , Schielicke R.
Published: July 2010

In drei Feldern werden am Palomar Observatory Sky Survey nach der Durchmessermethode die Helligkeiten und Farben aller Sterne bestimmt, die im blauen Farbbereich heller sind als im roten. Unter der Voraussetzung, daß es sich zum überwiegenden Teil um weiße Zwerge handelt, wird deren Häufigkeit in der Sonnenumgebung zu 3.38 · 10‐1 pc‐3 abgeschätzt.
Iterative Verbesserung der Positionen und Eigenbewegungen von Anhaltsternen in einem mehrfach überdeckten Sternfeld
Authors: Dieckvoss W. , De Vegt R.
Published: July 2010

Es wird ein iterativer Ansatz für die Verbesserung der Positionen und Eigenbewegungen von Anhaltsternen angegeben und mit Hilfe eines künstlichen Sternfeldes numerisch geprüft. Dabei ergibt sich eine wesentliche Genauigkeitssteigerung für die resultierenden Plattenkonstanten.
Ein allgemeines ALGOL‐Programm für lineare Ausgleichungen nach der Methode der kleinsten Quadrate
Authors: De Vegt ChR.
Published: July 2010

An ALGOL‐procedure for least squares solutions with N unknown parameters and M right hand sides is described, assuming a linearised set of equations of conditions.
Johnson‐Cousins magnitudes of comparison stars in the fields of ten Seyfert galaxies
Authors: Mihov B. M. , Slavcheva‐Mihova L. S.
Published: July 2010

We present UBVRCIC magnitudes of 49 comparison stars in the fields of the Seyfert galaxies Mrk 335, Mrk 79, Mrk 279, Mrk 506, 3C 382, 3C 390.3, NGC 6814, Mrk 304, Ark 564, and NGC 7469 in order to facilitate the photometric monitoring of these objects; 36 of the stars have not been calibrated before. The comparison stars are situated in 5 × 5 arcmin fields centred on the Seyfert galaxies, their V band flux ranges from 11.7 to 18.2 mag with a median value of 16.3 mag, and their B – V colour index ranges from 0.4 to 1.6 mag with a median value of 0.8 mag. The median errors of the calibrated UBVRCIC magnitudes are 0.08, 0.04, 0.03, 0.04, and 0.06 mag, respectively. Comparison stars were calibrated for the first time in three of the fields (Mrk 506, 3C 382, and Mrk 304). The comparison sequences in the other fields were improved in various aspects. Extra stars were calibrated in four fields (Mrk 335, Mrk 79, NGC 6814, and NGC 7469) – most of these stars are fainter and are situated closer to the Seyfert galaxies compared to the existing comparison stars. The passband coverage of the sequences in five fields (Mrk 335, Mrk 79, Mrk 279, NGC 6814, and Ark 564) was complemented with the U band. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Correlation between the Mayan calendar and ours: Astronomy helps to answer why the most popular correlation (GMT) is wrong
Authors: Klokočník J. , Kostelecký J. , Böhm V. , Böhm B. , Vondrák J. , Vítek F.
Published: July 2010

The Maya used their own very precise calendar. When transforming data from the Mayan calendar to ours, or vice versa, a surprisingly large uncertainty is found. The relationship between the two calendars has been investigated by many researchers during the last century and about 50 different values of the transformation coefficient, known as the correlation, have been deduced. They can differ by centuries, potentially yielding an incredibly large error in the relation of Mayan history to the history of other civilizations. The most frequently used correlation is the GMT one (of Goodman‐Martínez‐Thompson), based largely on historical evidence from colonial times. Astronomy (celestial mechanics) may resolve the problem of the correlation, provided that historians have correctly decoded the records of various astronomical phenomena discovered, namely, in one extremely important and rare Mayan book, the Dresden Codex (DC). This describes (among other matters) observations of various astronomical phenomena (eclipses, conjunctions, maximum elongations, heliacal aspects, etc), made by the Maya. Modern celestial mechanics enables us to compute exactly when the phenomena occurred in the sky for the given place on the Earth, even though far back in time. Here we check (by a completely independent method), confirming the value of the correlation obtained by Böhm & Böhm (1996, 1999). In view of these tests, we advocate rejecting the GMT correlation and replacing it by the Böhm's correlation. We also comment on the criticism of GMT by some investigators. The replacement of GMT by another correlation seems, however, unacceptable to many Mayanists, as they would need to rewrite the whole history of Mesoamerica. The history of the Maya would be – for example with Böhm's correlation – closer to our time by 104 years. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Integrated spectral properties of four previously unstudied small angular size galactic open clusters
Authors: Palma T. , Ahumada A.V. , Clariá J.J. , Bica E.
Published: July 2010

We have derived fundamental parameters for the previously unstudied concentrated Galactic open clusters Berkeley 77, NGC2587, BH58 and ESO324‐SC15 by means of integrated spectroscopy in the range 3800–6800 Å. The cluster integrated spectra are compared with those of solar metallicity template spectra of Galactic open clusters with known parameters. The spectra were obtained at CASLEO (San Juan, Argentina) with a resolution of 14 Å.We estimated simultaneously age and foreground interstellar reddening by comparing the continuum distribution and line strengths of the cluster spectra with those of template spectra. Berkeley 77 was found to be an old cluster of 3–4 Gyr, while the remaining three clusters are between 400 and 1000 Myr old. The derived foreground reddening values range from E (B – V) = 0.0 in NGC2587 and ESO324‐SC15 to approximately 0.30 in Berkeley 77. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preliminary orbital elements of six visual binary stars
Authors: Scardia M. , Prieur J.‐L. , Pansecchi L. , Argyle R.W.
Published: July 2010

Preliminary new orbital elements were computed for the visual binary stars A 1 ‐ ADS 1345, A 2629 ‐ ADS 3610, BU 560 ‐ ADS 4371, STF 3115 ‐ ADS 4376, STF 1426 AB ‐ ADS 7730 and STF 2437 ‐ ADS 11956. Using Straizys and Kuriliene's data, we derived new formulae for computing dynamical parallaxes for luminosity classes IV and V. The values found for those systems are in agreement with the Hipparcos parallaxes and the corresponding systemic masses are consistent with the spectral types. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modeling the dynamical profile of a BL Lacertae object
Authors: Papadopoulos N.J. , Caranicolas N.D.
Published: July 2010

A simple dynamical model for a BL Lacertae active galaxy is presented. The model consists of a logarithmic potential with an additional term representing internal perturbations. The time independent and the evolving model are investigated. In both cases we search for regular and chaotic motion and study the velocity distribution near the centre of the system. Numerical calculations suggest that responsible for the chaotic phenomena is the internal perturbation, the flattening parameter and the dense nucleus. The radius of the nucleus also affects the maximum velocity in the central regions of the galaxy. Our numerical outcomes are supported by theoretical arguments and analytical calculations. A linking of our numerical outcomes to observational data is also presented. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Diamagnetic pumping near the base of a stellar convection zone
Authors: Kitchatinov L.L. , Rüdiger G.
Published: July 2010

The property of inhomogeneous turbulence in conducting fluids to expel large‐scale magnetic fields in the direction of decreasing turbulence intensity is shown as important for the magnetic field dynamics near the base of a stellar convection zone. The downward diamagnetic pumping confines a fossil internal magnetic field in the radiative core so that the field geometry is appropriate for formation of the solar tachocline. For the stars of solar age, the diamagnetic confinement is efficient only if the ratio of turbulent magnetic diffusivityηTof the convection zone to the (microscopic or turbulent) diffusivityηinof the radiative interior isηT/ηin≥105. Confinement in younger stars requires largerηT/ηin. The observation of persistent magnetic structures on young solar‐type stars can thus provide evidence for the nonexistence of tachoclines in stellar interiors and on the level of turbulence in radiative cores. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Guiding trustful behavior: The role of accessible content and accessibility experiences
Authors: Greifeneder Rainer , Müller Patrick , Stahlberg Dagmar , van den Bos Kees , Bless Herbert
Published: July 2010

Trust has been identified as a key ingredient to the prosperity of close relationships, organizations, and societies. While research mainly focused on the antecedents and consequences of trust, much less is known about how individuals assess whether there are enough reasons to warrant trustful action. Two experiments explored the how and when of this assessment, suggesting that antecedents may not only be integrated as content information per se (as generally assumed), but in a feeling‐based summary form. Specifically, our results show that the ease or difficulty associated with the identification of antecedents to trust may guide trustful behavior. Furthermore, it is shown that such a feeling‐based influence is particularly likely to occur in conditions of personal certainty. Together these results extend prior research in the domains of trust and economic games, and further attest to the fundamental role cognitive feelings play in social life. Copyright © 2010 John Wiley & Sons, Ltd.