bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence of asthma‐like symptoms in young children
Authors: Bisgaard Hans , Szefler Stanley
Published: June 2007

Objective

To determine the prevalence, impact, and treatment of asthma‐like symptoms in preschool children in USA and Europe.

Study Design

7251 households in USA and Europe with at least one child aged 1–5 years were interviewed by telephone for recurrent days troubled by cough, wheeze or breathlessness during the recent 6 winter months.

Results

9490 young children were identified, 32% of whom were reported to suffer from recurrent days with troublesome cough, wheeze or breathlessness. Detailed interview with the 2700 mothers of the symptomatic children showed that 24% of this interview population suffered weekly symptoms despite current treatment with considerable impact on lifestyle and healthcare resource use. Antibiotics, cough‐ and herbal‐medications were the most commonly used treatments. Anti‐asthmatic and anti‐allergy agents were prescribed in the order: inhaled β2‐agonists > inhaled corticosteroid > oral anti‐histamines > oral corticosteroids. The reported symptom burden was higher in Southern Europe and there were pronounced regional differences in treatment and diagnostic terms.

Conclusions

Recurrent days with cough, wheeze or breathlessness in preschool children represents a major cause of morbidity in preschool children despite current treatment. There is a striking lack of international consensus on diagnosis and treatment. This uncontrolled morbidity highlights a significant unmet clinical need in preschool children. Pediatr Pulmonol. 2007, 42:723–728. © 2007 Wiley‐Liss, Inc.
Prostatic stromal cells derived from benign prostatic hyperplasia specimens possess stem cell like property
Authors: Lin Victor K. , Wang Shih‐Ya , Vazquez Dolores V. , C. Xu Chet , Zhang Sheng , Tang Liping
Published: June 2007

INTRODUCTION

The hyper‐proliferative activity of stromal smooth muscle (SM) cells is believed to be responsible for the pathogenesis of benign prostatic hyperplasia (BPH). We have observed that those stromal cells can differentiate into unrelated specialized cells. We thus hypothesize that stromal cells derived from adults prostate specimens may contain adult stem cells. To test this hypothesis, human prostate stromal primary cultures were established and used for characterization of their stem cell properties.

METHODS

Immunoblotting, immunohistochemistry, RT‐PCR, and tissue culture techniques were used to characterize the primary cultured human prostate‐derived stromal cells for their stem cell and differentiation properties. The plasticity of these stromal cells was analyzed using cell culture and histology techniques.

RESULTS

Primary cultured prostate stromal cells from BPH patient possess polygonal and elongated fibroblast/myofibroblast cellular morphology. They are positive in CD30, CD34, CD44, NSE, CD133, Flt‐1, stem cell factor (SCF), and neuron‐specific enolase (NSE), but negative in C‐Kit, stem cell antigen (SCA), SH2, CD11b. Expression of SM myogenic markers in these cells may be induced by sodium butyrate (NaBu) treatment. Induction to osteogenic and adipogenic differentiation in these cells is also evident.

CONCLUSIONS

Our study on primary stromal cells from BPH patients have yielded many interesting findings that these prostate stroma cells possess: (1) mesenchymal stem cell (MSC) markers; (2) strong proliferative potential; and (3) ability to differentiate or transdifferentiate to myogenic, adipogenic, and osteogenic lineages. These cell preparations may serve as a potential tool for studies in prostate adult stem cell research and the regulation of benign prostatic hyperplasia. Prostate 67: 1265–1276, 2007. © 2007 Wiley‐Liss, Inc.
Definition of an electrostatic relay switch critical for the cAMP‐dependent activation of protein kinase A as revealed by the D170A mutant of RIα
Authors: Abu‐Abed Mona , Das Rahul , Wang Lijun , Melacini Giuseppe
Published: June 2007

The Regulatory (R) subunit of Protein Kinase A (PKA) inhibits its kinase activity by shielding the Catalytic (C) subunit from physiological substrates. This inhibition is reversed in response to extra‐cellular signals that increase cAMP levels in the cytoplasm. Upon cAMP binding to R, C is allosterically released from R, activating a spectrum of downstream signaling cascades. Crystallographic data indicated that a series of distinct conformational changes within CBD‐A must occur to relay the cAMP signal from the cAMP binding site to the R:C interaction interface. One critical cAMP relay site within the CBD‐A of R has been identified as Asp170 because the D170A mutation selectively reduces the negative cooperativity between the cAMP‐ and C‐recognition sites (i.e. the KD for the R:C complex in the presence of cAMP is reduced by more than 12‐fold), without significantly compromising the high affinity of R for both binding partners. Here, utilizing an integrated set of comparative NMR analyses we have elucidated how this critical electrostatic switch is able to control the interaction network which transmits the cAMP signal within CBD‐A. The D170A‐induced variations in backbone chemical shifts as well as in hydrogen‐deuterium and hydrogen‐hydrogen exchange profiles show that Asp170 not only plays a pivotal role in controlling the local conformation of the phosphate binding cassette (PBC), where cAMP docks, but also significantly affects the long‐range cAMP‐dependent interaction network that extends from the PBC to the three major sites of C‐recognition. We also found that the D170A mutation promotes partial unfolding, thus assisting the uncoupling of the α‐ and β‐subdomains of CBD‐A as required for the major α‐helical conformational re‐arrangement necessary for C‐binding. Overall, the emerging map of allosteric networks features Asp170 as an essential component of an electrostatic switch mechanism that stabilizes the conformation of the PBC region for optimal interaction with cAMP and that is also crucial for relaying allosteric effects leading to C subunit activation. Taken together, our results consolidate the interdependence between the Asp170 relay site and the R:C interaction interface. Furthermore, they provide insight into the driving forces for the in vivo formation of intermediate PKA ternary complexes. Finally, our current study is relevant for elucidating the antagonistic properties of Rp‐cAMPS on PKA by providing a detailed picture of the long‐range effects of the altered interaction between this analog and the PBC. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Population change due to geographic mobility in Albania, 1989–2001, and the repercussions of internal migration for the enlargement of Tirana
Authors: Agorastakis Michalis , Sidiropoulos Giorgos
Published: June 2007

Being a country in transition, Albania has sustained vast political and socio‐economic changes over the past 15 years, mostly due to its engagement in democratisation and transformation to an open market economy. The pathway to transition has involved economic hardship and political unrest and has been accompanied by intense, large‐scale, geographical mobility. This paper describes population change due to internal and international migration, 1989–2001, using Census data at district level. Its contribution is a technical one in applying a method that allows new estimates to be made of the scale of internal migration in Albania.

Descriptive analysis of population changes in 36 Albanian districts, based on the last two censuses, lead to the identification of poles of attraction of internal migrants. Limited data concerning the 1989 Census and the 12 years between the censuses resulted in the creation of various indices that characterise internal migration, such as the Attraction and Expulsion Index stemming from the Origin–Destination Matrix of the districts. In addition an Index of Conservation of the population and an Index of External Migration were also derived at the district level. By considering internal and international migration as two separate phenomena, we emphasise their uniqueness in affecting population change in Albania. The District of Tirana, capital of Albania, absorbed the majority of the inflow of internal migrants. The latter part of the paper focuses on the population of Tirana as the county's major migration destination. Copyright © 2007 John Wiley & Sons, Ltd.
Force tracking neural block control for an electro‐hydraulic actuatorviasecond‐order sliding mode
Authors: Loukianov Alexander G. , Sanchez Edgar , Lizalde Carlos
Published: June 2007

This paper presents a novel scheme for identification and control of an electro‐hydraulic system using recurrent neural networks. The proposed neural network has the nonlinear block control form structure. A sliding‐mode control technique is applied then to design a discontinuous controller, which is able to track a force reference trajectory. Due to the presence of an unmodelled dynamics, the standard sliding‐mode controller produces oscillations (or ‘chattering’) in the closed‐loop system. The second‐order sliding mode is used to eliminate the undesired chattering effect. Simulations are presented to illustrate the results. Copyright © 2007 John Wiley & Sons, Ltd.
Comparison of information and variance maximization strategies for characterizing neural feature selectivity
Authors: Sharpee Tatyana O.
Published: June 2007

This paper compares several statistical methods for analyzing neural feature selectivity with natural stimuli. Despite the non‐Gaussian character of correlations in natural stimuli, several relevant stimulus dimensions can be found by maximizing either information or, as is demonstrated here, variance. In the case of information, the relevance of each dimension is quantified by a Kullback–Leibler divergence between the full input probability distribution and that across inputs associated with positive neural responses, both projected onto that dimension. We demonstrate that least‐square matching of the nonlinear prediction based on several dimensions relevant to the recorded spike trains yields an optimization scheme similar to information maximization. The relevant dimensions are found as those that capture the most variance in neural response. The variance along a stimulus dimension is given by a Rényi divergence of order 2 instead of the Kullback–Leibler divergence used for maximizing information. Statistical errors expected for the two schemes are shown to be similar through both analytical and numerical calculations. However, in the asymptotic limit of large spike numbers, maximizing information results in smaller errors than variance optimization. Numerical simulations for model cells with different noise levels show that this trend persists, and possibly increases, when the number of spikes decreases. This makes the problem of finding relevant dimensions one of the examples where information‐theoretic approaches are no more data limited than the variance‐based measures. Variance and information optimization also outperform methods based on the spike‐triggered average for all numbers of spikes and neural noise levels. Copyright © 2007 John Wiley & Sons, Ltd.
Successful Use of Peer Educators for Sharing Genetic Information
Authors: Venne Vickie L. , Hamann Heidi A.
Published: June 2007

This study examined the impact of a genetics education module provided by Reach to Recovery peer volunteers. Participants included 113 women with confirmed breast cancer diagnoses. Eighty‐eight of these women (78%) completed a baseline survey, participated in a peer‐led intervention, and completed a follow‐up survey. Approximately half of the women received an education module that included a genetic component, while the other half did not. Results indicated that women who received the genetics module had greater increases in genetics knowledge than the group that did not receive the module. However, follow‐up interest in genetic testing was not significantly different between the two groups. Results indicate that a peer‐led genetics module can increase knowledge about genetics. However, it does not appear to have a differential effect on genetic testing interest.
Determination of Glycerol in Wines Using 31P‐NMR Spectroscopy
Authors: Hatzakis Emanuel , Archavlis Eleftherios , Dais Photis
Published: June 2007

31P‐NMR spectroscopy was employed to detect and quantify glycerol in red wines from various regions of Greece. This novel analytical method was based on the derivatization of the hydroxyl groups of glycerol with 2‐chloro‐4,4,5,5‐tetramethyl dioxaphospholane, and identification of the phosphitylated compound on the basis of 31P chemical shifts. Quantification of glycerol in wines was accomplished by integration of appropriate signals in the 31P‐NMR spectrum and the use of the phosphitylated cyclohexanol as the internal standard. The method was reproducible (CV (%) = 2.35) and accurate (CV (%) = 1.34). Its applicability to glycerol quantification in wines was tested against a weighted amount of a glycerol‐model compound by linear regression analysis (R = 0.999; intercept = 0.074 ± 0.078; slope = 0.998 ± 0.003; p = 0.000). Furthermore, the NMR method was compared to the AOAC official method (HPLC) using the Bland and Altman statistical analysis. The distribution of the data points in the bias plot showed that 100% of the measurements of glycerol in 16 wine samples from various regions of Greece were within the limits of agreement of the two methods.
Staff Views and Behaviour Regarding Patient Involvement in Myocardial Infarction Care: Development and Evaluation of a Questionnaire
Authors: Arnetz Judith E. , Höglund Anna T. , Arnetz Bengt B. , Winblad Ulrika
Published: June 2007

Background: Healthcare legislation in several nations now dictates the responsibility of health care professionals to involve patients in decisions concerning care and treatment. However, few studies have examined the impact of patient involvement on the work of health care professionals. A better understanding of staff views and behaviour might enhance patient involvement.

Aim: The aim of this study was to develop and validate a questionnaire for measuring views and behaviour regarding patient involvement among physicians and nursing staff caring for patients with myocardial infarction.

Methods: Focus groups among cardiology staff provided the basis for the construction of the questionnaire. Questionnaire validity and reliability were evaluated in a small pilot study and a larger cross-sectional study among cardiology staff at twelve Swedish hospitals.

Results: The questionnaire demonstrated good validity and reliability, with two factors measuring staff views and four measuring behaviour.

Conclusion: The questionnaire appears to be a useful tool for evaluating the perceptions and behaviour of physicians and nursing staff regarding patient involvement in myocardial infarction care. Use of this questionnaire may provide insight regarding areas of staff–patient interaction that need improvement, as well as implications of patient involvement for the work of each professional group on cardiology wards.
Comparison of self-reports and biological measures for alcohol, tobacco, and illicit drugs consumption in psychiatric inpatients
Authors: de Beaurepaire Renaud , Lukasiewicz Michael , Beauverie Patrick , Castéra Sophie , Dagorne Odile , Espaze Renaud , Falissard Bruno , Giroult Patrick , Houery Michèle , Mahuzier Georges , Matheron Isabelle , Niel Philippe , Padovani Pierre , Poisson Nicole , Richier Jean-Paul , Rocher Jérôme , Ruetsh Odile , Touzeau Didier , Visinoni André , Molimard Robert
Published: June 2007

Background

Asking psychiatric in-patients about their drug consumption is unlikely to yield reliable results, particularly where alcohol and illicit drug use is involved. The main aim of this study was to compare spontaneous self-reports of drug use in hospitalized psychiatric patients to biological measures of same. A secondary aim was to determine which personal factors were associated with the use of tobacco, alcohol, and illicit drugs as indicated by these biological measures.

Methods

The consumption of substances was investigated using biological measures (urine cotinine, cannabis, opiates, cocaine, amphetamines and barbiturates; blood carbohydrate-deficient transferrin [CDT] and gamma-glutamyl transferase [GGT]) in 486 consecutively admitted psychiatric patients, one day following their hospitalization. Patients’ self-reports of alcohol, tobacco and illicit drugs consumption were recorded. Socio-professional and familial data were also recorded.

Results

The results show a low correlation between biological measures and self-reported consumption of alcohol and illicit drugs. Fifty-two percent of the patients under-reported their consumption of illicit drugs (kappa = .47). Patients with schizophrenia and personality disorders were more likely to disclose their illicit drug consumption relative to patients suffering from mood disorders and alcohol dependence. Fifty-six percent of patients underreported alcohol use, as evaluated by CDT (kappa = .2), and 37% underreported when using the CDT + GGT measure as an indicator. Smoking appeared to be reported adequately. In the study we observed a strong negative correlation between cannabis use and age, a strong correlation between tobacco and cannabis use, and correlations between tobacco, cannabis and alcohol consumption.

Conclusion

This study is the first to compare self-reports and biological measures of alcohol, tobacco and illicit drug uses in a large sample of inpatients suffering from various categories of psychiatric illnesses, allowing for cross-diagnosis comparisons.
Identification of an in vitro transcription‐based artifact affecting oligonucleotide microarrays
Authors: Nelson David C. , Wohlbach Dana J. , Rodesch Matthew J. , Stolc Viktor , Sussman Michael R. , Samanta Manoj P.
Published: June 2007

This study identified the widely used T7 in vitro transcription system as a major source of artifact in the tiling array data from nine eukaryotic genomes. The most affected probes contained a sequence motif complementary to the +1 to +9 initial transcribed sequence (ITS) of the T7‐(dT)24 primer. The abundance of 5′ ITS cRNA fragments produced during target preparation was sufficient to drive undesirable hybridization. A new T7‐(dT)24 primer with a modified ITS was designed that shifts the artifactual motifs as predicted and reduces the effect of the artifact. A computational algorithm was generated to filter out the likely artifactual probes from existing whole‐genome tiling array data and improve probe selection. Further studies of Arabidopsis thaliana were conducted using both T7‐(dT)24 primers. While the artifact affected transcript discovery with tiling arrays, it showed only a minor impact on measurements of gene expression using commercially available ‘gene‐only’ expression arrays.
Urea denaturation of α‐hemolysin pore inserted in planar lipid bilayer detected by single nanopore recording: Loss of structural asymmetry
Authors: Pastoriza-Gallego Manuela , Oukhaled Ghani , Mathé Jérôme , Thiebot Bénédicte , Betton Jean-Michel , Auvray Loïc , Pelta Juan
Published: June 2007

The aim of this work is to study pore protein denaturation inside a lipid bilayer and to probe current asymmetry as a function of the channel conformation. We describe the urea denaturation of α‐hemolysin channel and the channel formation of α‐hemolysin monomer incubated with urea prior to insertion into a lipid bilayer. Analysis of single‐channel recordings of current traces reveals a sigmoid curve of current intensity as a function of urea concentration. The normalized current asymmetry at 29 ± 4% is observed between 0 and 3.56 M concentrations and vanishes abruptly down to 0 concentration exceeds 4 M. The loss of current asymmetry through α‐hemolysin is due to the denaturation of the channel's cap. We also show that the α‐hemolysin pore inserted into a lipid bilayer is much more resistant to urea denaturation than the α‐hemolysin monomer in solution: The pore remains in the lipid bilayer up to 7.2 M urea. The pore formation is possible up to 4.66 M urea when protein monomers were previously incubated in urea.
Osmoadaptation‐dependent activity of microsomal HMG‐CoA reductase in the extremely halotolerant black yeast Hortaea werneckii is regulated by ubiquitination
Authors: Vaupotic Tomaz , Plemenitas Ana
Published: June 2007

We have investigated regulation of HMG‐CoA reductase (HMGR) in one of the most salt‐tolerant fungi, Hortaea werneckii, under different salinities and at the level of protein degradation. Two different HwHMGR isoenzymes were identified, specific to mitochondria and endoplasmic reticulum: HwHmg1 and HwHmg2, respectively. The activity of microsomal HwHmg2 is highest under hypo‐saline and extremely hyper‐saline conditions, and down‐regulated under optimal growth conditions. We show that this is due to intense ubiquitination and proteasomal degradation of HwHmg2. The activity of the truncated mitochondrial HwHmg1 is constant under different growth conditions, suggesting an osmoadaptation‐directed fate for mevalonate utilization in H. werneckii.
The temperature activated HtrA protease from pathogen Chlamydia trachomatis acts as both a chaperone and protease at 37 °C
Authors: Huston Wilhelmina M. , Swedberg Joaquim E. , Harris Jonathan M. , Walsh Terence P. , Mathews Sarah A. , Timms Peter
Published: June 2007

Characterization of the protease, HtrA, from pathogen Chlamydia trachomatis is presented. The purified recombinant protein was a serine endoprotease, specific for unfolded proteins, and temperature activated above 34 °C. Chaperone activity was observed, although this appeared target‐dependent. Inactive protease (S247A) was able to chaperone insulin B‐chain, irrespective of temperature, but at 30 °C only HtrA and not S247A displayed significant chaperone activity for α‐lactalbumin. These data demonstrate that chaperone activity may involve functional protease domain and that C. trachomatis HtrA functions as both a chaperone and protease at 37 °C. These properties are consistent with the developmental cycle of this obligate intracellular bacterium.
Access to sexual and reproductive health care: Adolescents and young people
Authors: Braeken D. , Otoo‐Oyortey N. , Serour G.
Published: June 2007

Obstetricians and gynecologists at the FIGO pre‐congress workshop on adolescents deliberated on their role as clinicians, educators and advocates in upholding young peoples’ sexual and reproductive health rights. Comprehensive services to adolescents should include emergency contraception, safe abortion and also provide care for survivors of sexual violence. Key to successful access to youth friendly services consist of providers’ attitudes and addressing consent, confidentiality, evolving capacities of young people and youth participation.
Strategic supply management, quality initiatives, and organizational performance
Authors: Yeung Andy C.L.
Published: June 2007

Researchers in supply chain management have found over the past two decades that supply management should be not merely a purchasing function but a strategic tool for supply chain integration. Supply management, the cornerstone of the integration of industrial supply chains, has evolved as a key research area. Based on quantitative and qualitative investigations of 225 electronics manufacturing firms, we examine the organizational impacts of strategic supply management (SSM) and the contexts of company size, process type, ISO 9000 certification, and quality management (QM) implementation that facilitate such an endeavor. We reveal that SSM is essentially a quality management initiative that requires bilateral efforts for continuous improvement and thus is not associated with the basic requirements of ISO 9000. We find that SSM improves on‐time shipments, reduces operational costs, and leads to customer satisfaction and improved business performance. Developed based on contemporary premises in supply chain and QM, this research refines our understanding of the relationships among quality initiatives, SSM, and organizational performance.
Abomasal nematodes of the red deerCervus elaphusin north-eastern Italy
Authors: Manfredi M.T. , Di Cerbo A.R. , Tranquillo V. , Nassuato C. , Pedrotti L. , Piccolo G.
Published: June 2007

The composition of the abomasal helminth fauna and parasite diversity were studied in 298 red deer collected during 1997–2000 from three different sectors (Bolzano, Trento and Sondrio provinces) of the Stelvio National Park, one of the main protected areas of north-eastern Italy. The association between parasite burdens and geographical areas of the hosts was assessed using the negative binomial regression. A variety of abomasal helminths, both host specific and generalist, was found in all sectors. The most commonly observed parasites were theSpiculopteragia spiculopteramorphspiculopteraandOstertagia leptospicularismorphleptospicularis, with prevalences of 79.5% and 40.9%, respectively. The minor morphsS. spiculopteramorphmathevossiani(prevalence 31.9%) andO. leptospicularismorphkolchida(18.8%) occurred at lower prevalences.Teladorsagia circumcinctamorphcircumcincta, Marshallagia marshallimorphmarshalliandHaemonchus contortuswere rarer, at prevalences of 1, 1.3 and 1.3%, respectively. Deviance analysis of the negative binomial regression model shows that the geographical area is significantly related to parasite burdens (P = 0.001). Prevalences of hosts with parasites were greater in the Sondrio (odds ratio = 1.31; 95% confidence interval: 0.16–10.85) and smaller in the Trento (odds ratio = 0.62; 95% confidence interval: 0.20–1.96) sectors with respect to Bolzano, but these differences were not statistically significant. Possible cross-infections by more generalist parasites between wild and domestic animals were also suggested, as deer and domestic ruminants (Bovinae, Caprinae and Ovinae) used the same feeding areas of the park sectors.
Nitazoxanide in the treatment of Ascaris lumbricoides in a rural zone of Colima, Mexico
Authors: Galvan-Ramirez M.L. , Rivera N. , Loeza M.E. , Avila X. , Acero J. , Troyo R. , Bernal R.
Published: June 2007

Intestinal parasites in Mexico are an endemic problem. A study was conducted in children, teenagers and adults in a rural community in Colima, Mexico to examine the prevalence and intensity of Ascaris lumbricoides infection and to evaluate the parasitological and clinical efficacy of nitazoxanide (NTZ). Two hundred and eighty children, teenagers and adults participated in this study. Parasitological diagnosis from faeces was confirmed by three consecutive stool samples using the floatation concentration Faust method. Egg counts were performed as described by the Kato–Katz technique before and after treatment. A questionnaire was systematically applied to obtain information about socio-economic status and hygienic habits. One hundred and six participants (38%) were diagnosed as harbouring intestinal parasites, and 86 of them (81%) were infected with A. lumbricoides. All patients with ascariasis infections underwent a complete physical examination before and after NTZ treatment. NTZ resolved 88% of the ascariasis cases, with a 89% clinical efficacy, and there was a 97.5% reduction in the levels of morbidity. The most intense infections for A. lumbricoides were found in housewives, and statistically significant associations were found between ascariasis and the absence of drainage and living in houses with dirt floors.
Public entrepreneurship and the economics of reform
Authors: SCHNELLENBACH JAN
Published: June 2007

Public entrepreneurship is commonly understood as the outcome of the activities of a Schumpeterian political innovator. However, empirical research suggests that changes to a more efficient economic policy, even if it is known and technically easy to implement, are usually delayed. This is difficult to reconcile with Schumpeterian notions of public entrepreneurship. In this paper, it is argued that the attempt to transfer a Schumpeterian approach to the public sector is fundamentally flawed. Institutional checks and balances that characterize most modern liberal democracies make the strategy of bold leadership an unlikely choice for an incumbent. If change occurs, it occurs normally as a response to the fact that the status quo has become untenable. From a normative point of view, it is argued that if public entrepreneurship nevertheless occurs, it will often be associated with unwanted consequences. A dismantling of formal institutional checks and balances is therefore not reasonable.
On the optimal specificity of legal rules
Authors: FON VINCY , PARISI FRANCESCO
Published: June 2007

Lawmakers can choose to craft laws with different levels of detail to guide judges in their decision-making process, incorporating rules or standards into the laws they write. The optimal degree of specificity of legal rules under different environmental conditions and the functionality of these rules or standards are the subjects of the present study. A basic model of optimal specificity of laws is presented, clarifying the relevance of legal obsolescence and volume of litigation in the optimal choice. We then consider the important influence of codification style, judges’ specialization, and complexity of reality on the optimal choice of legislative instrument. The implications of our results are then reexamined in light of the more complex institutional reality that characterizes contemporary legislative processes in various areas of the law.
EEG-Veränderungen unter Methylphenidat - eine Pilotstudie
Authors: Kerdar Madjid S. , Scheuerpflug Peter , Srdinko Petra , Wewetzer Christoph , Warnke Andreas , Romanos Marcel
Published: June 2007

Zusammenfassung: Fragestellung: Es existieren widersprüchliche Aussagen hinsichtlich der Senkung der sogenannten «Krampfschwelle» als mögliche unerwünschte Nebenwirkung von Methylphenidat. Die vorliegende Pilotstudie galt der empirischen Überprüfung dieser Behauptung sowie der quantitativen Erfassung von Änderungen elektrophysiologischer Parameter unter Methylphenidattherapie. Methodik: 15 Patienten mit ADHS im Alter von 6 bis 14 Jahren wurden elektrophysiologisch untersucht. Die Diagnosestellung des hyperkinetischen Syndroms erfolgte unter Einhaltung aller Kriterien der ICD-10-Klassifikation durch eine multiaxiale Diagnostik. Die EEG-Ableitungen wurden zur Beurteilung der elektrophysiologischen Auswirkungen von Methylphenidat hinsichtlich der spektralen Frequenzzusammensetzung sowie dem Vorhandensein pathologischer Korrelate ausgewertet. Ergebnisse: Die FFT-Analyse der EEG-Daten vor und nach der Behandlung mit Methylphenidat zeigte eine Zunahme der okzipitalen Alpha-Aktivität gegenüber der Delta-Theta-Aktivität. Weiterhin konnte eine Zunahme der Beta-Aktivität in der Zentral-Region und ein Trend zur Zunahme der Beta-Aktivität in der Frontal-Region registriert werden. Es wurden in diesem Patientenkollektiv weder vor noch nach der Behandlung mit Methylphenidat pathologische EEG-Veränderungen registriert. Schlussfolgerung: Die Ergebnisse unterstützen die mehrheitliche Auffassung in der Literatur, dass Methylphenidat nicht zu einer Senkung der Krampfschwelle führt. Vielmehr kann eine EEG-Normalisierung im Sinne einer Beschleunigung der Grundaktivität nachvollzogen werden.
Kurz-, mittel- und längerfristige Effekte eines Trainings in phonologischer Bewusstheit und in Buchstaben-Laut-Korrespondenz auf die phonologische Bewusstheit und die Lese- und Rechtschreibleistung
Authors: Blaser Regula , Preuss Ulrich , Groner Marina , Groner Rudolf , Felder Wilhelm
Published: June 2007

Zusammenfassung: Fragestellung: Die vorliegende Studie hatte zum Ziel, die kurz, mittel- und längerfristige Wirksamkeit eines vorschulischen Trainings in phonologischer Bewusstheit und in Buchstaben-Laut-Korrespondenz, durchgeführt in Schweizer Mundart an einer Schweizer Stichprobe, an Hand der Outcomevariablen phonologische Bewusstheit und Lese- und Rechtschreibleistungen zu überprüfen. Methodik: Aus insgesamt 109 Kindern mit vollständigen Datensätzen über den Erhebungszeitraum wurde für die statistischen Analysen eine gepaarte Stichprobe aus je 26 Kindern aus Experimental- und Kontrollgruppe extrahiert. Es wurden einerseits Effekte des Trainings auf die kurz, mittel- und längerfristige Entwicklung der phonologischen Bewusstheit untersucht, andererseits die mittleren Lese- und Rechtschreibleistungen von Trainings- und Kontrollgruppe sowie der Anteil an lese- und rechtschreibschwachen Kindern in den jeweiligen Gruppen am Ende des 1. und 2. Schuljahres verglichen. Ergebnisse: Effekte des Trainings auf die phonologische Bewusstheit ließen sich bis zum Beginn des 1. Schuljahres nachweisen. Auf die mittleren Lese- und Rechtschreibleistungen am Ende beider Schuljahre zeigte das Training keinen Effekt, hingegen konnte der Anteil an rechtschreibschwachen Kindern durch das Training deutlich reduziert werden. Schlussfolgerungen: Insgesamt werden die Befunde als Bestätigung der Wirksamkeit des Trainings in der primären Prävention von Lese- und Rechtschreibschwierigkeiten gewertet.
Die Behandlung von Jugendlichen mit Leistungsstörungen mit dem Therapieprogramm SELBST - Konzept und Stabilität der Veränderungen während der Therapie
Authors: Walter Daniel , Döpfner Manfred
Published: June 2007

Zusammenfassung: Fragestellung: Leistungsstörungen bei Jugendlichen sind häufig und bedeuten eine erhebliche Gefahr für die weitere Entwicklung. Die bislang vorliegenden Therapieprogramme und Ratgeber sind nur unzureichend evaluiert. SELBST - ein Therapieprogramm für Jugendliche mit Selbstwert-, Leistungs- und Beziehungsstörungen ist ein klinisches, kognitiv-behaviorales Behandlungsprogramm, das häufige Probleme bei Jugendlichen aufgreift. Das Modul SELBST-Leistungsprobleme versucht, schulische Leistungen zu verbessern, indem die Leistungsmotivation gestärkt, Lernstrategien verbessert, eine angemessene Mitarbeit im Unterricht erarbeitet und fachbezogene Wissenslücken verringert werden. Methodik: Im Rahmen einer Studie an einer klinischen Inanspruchnahmepopulation wurden zehn Jugendliche im Alter zwischen 13 und 18 Jahren in die Untersuchung eingeschlossen. Ziel dieser Studie war es, erste Hinweise auf die Stabilität der erreichten Behandlungseffekte bei Jugendlichen mit Leistungsstörungen zu erhalten. Hierzu wurden 3-, 6-, 9-, und 12-Monatskatamnesen im Jugendlichen-, Eltern- und Lehrerurteil erhoben. Ergebnisse: Die deutliche Verminderung von Leistungsstörungen und von komorbiden Problemen während der Behandlung erwies sich über den Zeitraum von einem Jahr als stabil. Die Aussagekraft der vorliegenden Studie ist durch die fehlende experimentelle Kontrolle und die geringe Stichprobengröße begrenzt. Schlussfolgerung: In dieser Pilotstudie konnten an einer kleinen Stichprobe erste Hinweise auf die Effektivität und Stabilität des Therapieprogramms SELBST bei der Behandlung von Jugendlichen mit Leistungsstörungen gesammelt werden.
Nonvolcanic seafloor spreading and corner‐flow rotation accommodated by extensional faulting at 15°N on the Mid‐Atlantic Ridge: A structural synthesis of ODP Leg 209
Authors: Schroeder Timothy , Cheadle Michael J. , Dick Henry J. B. , Faul Ulrich , Casey John F. , Kelemen Peter B.
Published: June 2007

Drilling during ODP Leg 209, dredging, and submersible dives have delineated an anomalous stretch of the Mid‐Atlantic Ridge north and south of the 15°20′N Fracture Zone. The seafloor here consists dominantly of mantle peridotite with gabbroic intrusions that in places is covered by a thin, discontinuous extrusive volcanic layer. Thick lithosphere (10–20 km) in this region inhibits magma from reaching shallow levels beneath the ridge axis, thereby causing plate accretion to be accommodated by extensional faulting rather than magmatism. The bathymetry and complex fault relations in the drill‐core suggest that mantle denudation and spreading are accommodated by a combination of high‐displacement, rolling‐hinge normal faults and secondary lower‐displacement normal faults. These extensional faults must also accommodate corner flow rotation (up to 90°) of the upwelling mantle within the shallow lithosphere, consistent with remnant magnetic inclinations in denuded peridotite and gabbro from Leg 209 core that indicate up to 90° of sub‐Curie‐temperature rotation.
Preferential dissolution of benthic foraminiferal calcite during laboratory reductive cleaning
Authors: Yu Jimin , Elderfield Henry , Greaves Mervyn , Day Jason
Published: June 2007

We have investigated the effect of cleaning procedures on eight element/Ca ratios in three widely used benthic foraminifera species from core top and down core sediments. Two cleaning techniques were employed: (1) comparison between “Mg‐cleaning” and “Cd‐cleaning” methods and (2) comparison between the various constituent reagents. Li/Ca, B/Ca, and Sr/Ca ratios remained unchanged for samples subjected to different treatments, but Mg/Ca, Mn/Ca, Zn/Ca, Cd/Ca, and U/Ca were substantially decreased when foraminifera shells were cleaned with reagents containing citrate. In contrast, no significant decreases in element/Ca ratios were observed for samples cleaned in N2H4 without citrate, indicating that the role of N2H4 was insignificant during reductive cleaning and that citrate is responsible for decreases of Mg/Ca, Mn/Ca, Zn/Ca, Cd/Ca, and U/Ca. Decreases in these ratios are most likely due to (1) removal of contaminant particles enriched in Mg, Mn, Zn, Cd and U and/or (2) preferential leaching of CaCO3 by the formation of stable metal complexes through chelation between citrate and metals heterogeneously distributed in foraminiferal shells. Due to the negligible effect of N2H4 and preferential dissolution of CaCO3 during reductive cleaning, it is suggested that the reductive cleaning step should be omitted and the “Mg‐cleaning” method [Barker et al., 2003] could be employed to clean foraminiferal shells for trace element measurements.
A global index earthquake approach to probabilistic assessment of extremes
Authors: Thompson Eric M. , Baise Laurie G. , Vogel Richard M.
Published: June 2007

This paper applies recent innovations in flood frequency analysis to regional series of earthquake magnitudes in the global Centroid Moment Tensor (CMT) catalog from 1976 to 2005. Probability plot correlation coefficient hypothesis tests andL‐moment goodness‐of‐fit evaluations reveal that the Gumbel (GUM) distribution provides a good approximation to the probability distribution function (pdf) of series of annual maximum (AM) earthquake magnitudes. Homogeneity tests based on the theory ofL‐moments further reveal that broad regions of the globe are homogeneous in the sense that the AM observations of earthquake magnitudes are well approximated by a GUM pdf with fixed upper moments. The homogeneity of global earthquake data across broad tectonic environments enables us to pool data into a regional pdf of earthquake magnitudes, termed an index earthquake distribution. Research in hydrology has shown that frequency analysis based on pooling of data using an analogous index‐flood method are much more accurate than frequency analysis based on site or region specific data. The index earthquake distribution is a dimensionless GUM distribution with fixed scale parameter so only the mean earthquake magnitude must be estimated for a region to define the frequency distribution of large earthquakes. We show how the degree of spatial homogeneity of earthquake magnitudes across broad tectonic environments can be exploited to yield improved estimates of the risk posed by extreme earthquake magnitudes.
Structure of the California Coast Ranges and San Andreas Fault at SAFOD from seismic waveform inversion and reflection imaging
Authors: Bleibinhaus Florian , Hole John A. , Ryberg Trond , Fuis Gary S.
Published: June 2007

A seismic reflection and refraction survey across the San Andreas Fault (SAF) near Parkfield provides a detailed characterization of crustal structure across the location of the San Andreas Fault Observatory at Depth (SAFOD). Steep‐dip prestack migration and frequency domain acoustic waveform tomography were applied to obtain highly resolved images of the upper 5 km of the crust for 15 km on either side of the SAF. The resulting velocity model constrains the top of the Salinian granite with great detail. Steep‐dip reflection seismic images show several strong‐amplitude vertical reflectors in the uppermost crust near SAFOD that define an ∼2‐km‐wide zone comprising the main SAF and two or more local faults. Another prominent subvertical reflector at 2–4 km depth ∼9 km to the northeast of the SAF marks the boundary between the Franciscan terrane and the Great Valley Sequence. A deep seismic section of low resolution shows several reflectors in the Salinian crust west of the SAF. Two horizontal reflectors around 10 km depth correlate with strains of seismicity observed along‐strike of the SAF. They represent midcrustal shear zones partially decoupling the ductile lower crust from the brittle upper crust. The deepest reflections from ∼25 km depth are interpreted as crust‐mantle boundary.
Enhanced turbulence due to the superposition of internal gravity waves and a coastal upwelling jet
Authors: Avicola G. S. , Moum J. N. , Perlin A. , Levine M. D.
Published: June 2007

The upwelling‐driven coastal jet off Oregon is in geostrophic balance to first order. The accompanying thermal wind shear is stable to shear instability. Yet enhanced turbulence is observed in the upwelling jet, typically as long, thin patches with horizontal to vertical aspect ratios of 102 to 103 (median value ∼300). These patches are clearly defined by regions of low Richardson number and occur where and when the linear superposition of the three dominant shear constituents (near‐inertial, M2, and thermal wind) interferes constructively. This is most pronounced at the base of the coastal jet, where the thermal wind shear is largest. While the effect of the turbulence stress divergence on the jet is small compared to geostrophy (∼1%), it is significant in the second‐order force balance governing secondary circulation. The timescale associated with the decay of the thermal wind shear via turbulence stress is O(10) days. We confirm that the vertical salt flux due to mixing is comparable to the net Ekman transport of salt onto the shelf within the bottom boundary layer. Because numerical models of coastal circulation lack turbulence in midwater column, any vertical transport of scalars, including salt and heat, must be achieved inshore of the 40‐m isobath. This is inconsistent with the observations presented in this study, in which significant vertical turbulent salt transport is found to exist across the entire shelf.
Physical and chemical properties of the aerosol within the southeastern Pacific marine boundary layer
Authors: Tomlinson Jason M. , Li Runjun , Collins Don R.
Published: June 2007

During the Stratus 2003 and 2004 cruises, a Differential Mobility Analyzer/Tandem Differential Mobility Analyzer (DMA/TDMA) was used to measure the size‐resolved concentration, hygroscopicity, and volatility of the submicron aerosol below the stratocumulus deck of the southeastern Pacific. The number size distributions were typically bimodal, although a nucleation event in 2003 skewed the relative importance of the two modes, while in 2004, influence from anthropogenic sources near the coast of Chile reduced the separation between the two modes. The average total aerosol number concentration was 398 ± 145 cm−3 and 301 ± 100 cm−3 for the 2003 and 2004 cruises, respectively. Measured size‐ and temperature‐dependent volatility suggested Aitken and accumulation mode particles were composed of refractory cores and acidic sulfate solutions having NH4/SO4 molar ratios of roughly 0.56 and 0.23, respectively. Cloud condensation nuclei (CCN) concentrations at the peak in‐cloud supersaturation and over a range in supersaturation were calculated using the collected data. The data were also used to quantify the number to volume concentration ratio of the accumulation mode aerosol.
Autoregressive models of background errors for chemical data assimilation
Authors: Constantinescu Emil M. , Chai Tianfeng , Sandu Adrian , Carmichael Gregory R.
Published: June 2007

The task of providing an optimal analysis of the three state of the atmosphere requires to efficiently integrate the observational data and the models, a process called data assimilation. The background, or initial state of an atmospheric model, is not known exactly, and can be correctly represented only in a probabilistic framework that accounts for the uncertainty. It is widely accepted that a key ingredient of successful data assimilation is a realistic estimation of the background error distribution. This paper introduces a new method for modeling the background errors as autoregressive processes. The method is motivated by a theoretical analysis of error propagation through the linearized transport and chemical equations. The proposed approach is computationally inexpensive, captures the error correlations along the flow lines, and results in nonsingular background covariance matrices. We illustrate the benefits of the autoregressive background covariance matrix in a four‐dimensional Var experiment that uses real data.
Recent formation and evolution of northern Martian polar layered deposits as inferred from a Global Climate Model
Authors: Levrard B. , Forget F. , Montmessin F. , Laskar J.
Published: June 2007

We present a time‐marching model which simulates the exchange of water ice between the Martian northern cap, the tropics, and a high‐latitude surface reservoir. Net annual exchange rates of water and their sensitivity to variations in orbital/rotational parameters are examined using the Martian water cycle modeled by the LMD three‐dimensional Global Climate Model. These rates are propagated over the last 10 Myr to follow the thickness of the reservoirs. The effect of a sublimation dust lag is taken account to test simple models of layer formation. Periods of high mean polar summer insolation (∼5–10 Ma ago) lead to a rapid exhaustion of a northern polar cap and a prolonged formation of tropical glaciers. The formation of a northern cap and of a high‐latitude icy mantle may have started 4 Ma ago with the average decrease of polar insolation. Tropical ice may have disappeared around 2.7 Ma ago, but small glaciers could have formed during the last peaks of polar summer insolation. Over the last 4 Myr, most of the present cap may have formed at the expense of tropical and high‐latitude reservoirs forming distinct layers at almost each ∼51‐kyr/120‐kyr insolation cycle. Layers thickness ranges from 10 to 80 m, variations being produced by the modulation of the obliquity with ∼2.4 and 1.3 Myr periods. Because only ∼30 insolation cycles have occurred since 4 Ma ago, we found an inconsistency between the recent astronomical forcing, the observed number of layers, and simple astronomically based scenarios of layers formation.
Permafrost monitoring in the Hovsgol mountain region, Mongolia
Authors: Sharkhuu Anarmaa , Sharkhuu N. , Etzelmüller Bernd , Heggem Eva S. Flo , Nelson F. E. , Shiklomanov N. I. , Goulden Clyde E. , Brown Jerry
Published: June 2007

The Hovsgol mountain region (49°–52°N, 98°–102°E) of northern Mongolia contains widespread mountain permafrost and comprises the southern fringe of the Siberian continuous permafrost zone. In this paper, we report our initial monitoring of permafrost by means of measuring ground temperatures and active layer thickness in boreholes and some cryogenic processes under the influence of climate warming and human activities in the region. The average rate of increase in mean annual permafrost temperatures is from 0.2°C to 0.4°C per decade. Permafrost has been degrading more intensively during the last 15 years (since 1990s) than during the previous 15–20 years (1970s and 1980s). Recent degradation of permafrost under climate warming in the Hovsgol mountain region is generally more intensive than in the Hentei and Hangai Mountain regions. Moreover, livestock grazing in some local areas accelerates degradation of permafrost due to loss of vegetation cover. Year‐round temperature recordings by data loggers placed beneath different vegetation covers showed marked differences in active layer thickness and ground temperature.