bluuebunny/crossref_metadata_2025 huggingface dataset:
High‐resolution melting analysis, a simple and effective method for reliable mutation scanning and frequency studies in the ACADVL gene
Authors: Olsen Rikke Katrine Jentoft , Dobrowolski Steven F. , Kjeldsen Margrethe , Hougaard David , Simonsen Henrik , Gregersen Niels , Andresen Brage Storstein
Published: May 2010

Expanded newborn screening uses tandem mass spectrometry (MS/MS) to identify patients affected with fatty acid oxidation defects by the presence of pathological acylcarnitine esters. A caveat to MS/MS assessment is that cut‐off values for disease‐specific acylcarnitines does not always clearly discriminate affected patients from carriers and healthy individuals. Diagnostic evaluation of screening‐positive samples is required to confirm a metabolic deficiency. With MS/MS newborn screening becoming established in a growing number of countries, streamlined means for time‐ and ‐effective follow‐on diagnostic evaluation is essential. Moreover, studies to evaluate the diagnostic accuracy of MS/MS newborn screening are needed for determination and adjustment of precise cut‐off values for the disease‐specific acylcarnitines. In the current study, we use the fatty acid oxidation disorder very‐long‐chain acyl‐CoA dehydrogenase deficiency (VLCADD), the second most common fatty acid oxidation disorder detected by expanded newborn screening, to demonstrate accurate and fast diagnostic evaluation of the ACADVL gene utilizing DNA extracted from the newborn screening dried bloodspot and high resolution melt (HRM) profiling. We also demonstrate that HRM is a very effective means to determine carrier frequency of prevalent ACADVL mutations in the general population. Based on estimates of the expected disease incidence, we discuss the diagnostic accuracy of MS/MS‐based newborn screening to identify VLCADD in Denmark.
APOA1/A5Variants and Haplotypes as a Risk Factor for Obesity and Better Lipid Profiles in a Brazilian Elderly Cohort
Authors: Chen Elizabeth Suchi , Furuya Tatiane Katsue , Mazzotti Diego Robles , Ota Vanessa Kiyomi , Cendoroglo Maysa Seabra , Ramos Luiz Roberto , Araujo Lara Quirino , Burbano Rommel Rodriguez , de Arruda Cardoso Smith Marília
Published: May 2010

Genetic variations in theAPOA1/C3/A4/A5gene cluster have been studied and proposed to be the leading key for susceptibility to cardiovascular diseases and age‐associated disorders. We aimed to investigate the associations of rs12721026 (APOA1) and rs1729408 (APOA5) polymorphisms and their haplotypes with some age‐related diseases, as well as with lipids and proteins serum levels in a cohort from a Brazilian Elderly Longitudinal Study (EPIDOSO). Genotyping was performed by polymerase chain reaction restriction fragment length polymorphism (PCR‐RFLP). Statistical analyses were carried out using logistic regression analysis, Student'st‐test, and linkage disequilibrium (LD) analysis. Polymorphic allele frequencies were 0.095 and 0.449 for rs12721026 and rs1729408, respectively. The C‐allele of rs1729408 was associated with higher high‐density lipoprotein (HDL) (P= 0.022) and glycated hemoglobin levels (P= 0.020). We also showed that rs12721026 and rs1729408 were in LD. The GC haplotype, which is composed of the G‐allele of rs12721026 and the C‐allele of rs1729408, was significantly associated with obesity (P= 0.028), with higher glycated hemoglobin (P= 0.006), and fasting glucose (P= 0.0003) compared to the TT haplotype, which includes the wild‐type alleles of both polymorphisms. Moreover, we found an association between the TC haplotype and higher HDL levels (P= 0.0039). This is the first time that haplotypes involving these polymorphisms were evaluated. Our results showed that these polymorphisms were involved in the development of obesity and in alterations of lipids and proteins serum levels in a Brazilian population. The present findings might also clarify the role of these polymorphisms and their haplotypes in lipids and proteins metabolism.
Seed Composition and Seed Oil Antioxidant Activity of Maize Under Water Stress
Authors: Ali Qasim , Ashraf Muhammad , Anwar Farooq
Published: May 2010

The changes in seed composition and seed oil quality and antioxidant capacity in two maize cultivars Agaiti‐2002 (drought tolerant) and EV‐1098 (drought sensitive) grown under field drought conditions were assessed. Both maize varieties used in the present study are widely cultivated in Pakistan and are an important source for developing different maize hybrids. At the early vegetative stage, plants of both maize cultivars were subjected to normal irrigation and water stress conditions. Overall, seed oil, α‐, γ‐, δ‐ and total tocopherols, and flavonoids increased considerably due to water stress in both cultivars. However, oil phenolics carotenoid and DPPH scavenging activity were decreased due to water stress. By drawing on the relationship between different components of seed oil such as oil lipophilic antioxidant compounds, seed oil phenolics carotenoid and DPPH scavenging activity; it is clear that oil antioxidant activity was positively associated with oil phenolic and carotenoid contents.
A Method for Serial Tissue Processing and Parallel Analysis of Aberrant Crypt Morphology, Mucin Depletion, and Beta-Catenin Staining in an Experimental Model of Colon Carcinogenesis
Authors: McGinley John N , Thompson Matthew D , Thompson Henry J
Published: May 2010

The use of architectural and morphological characteristics of cells for establishing prognostic indicators by which individual pathologies are assigned grade and stage is a well-accepted practice. Advances in automated micro- and macroscopic image acquisition and digital image analysis have created new opportunities in the field of prognostic assessment; but, one area in experimental pathology, animal models for colon cancer, has not taken advantage of these opportunities. This situation is primarily due to the methods available to evaluate the colon of the rodent for the presence of premalignant and malignant pathologies. We report a new method for the excision and processing of the entire colon of the rat and illustrate how this procedure permitted the quantitative assessment of aberrant crypt foci (ACF), a premalignant colon pathology, for characteristics consistent with progression to malignancy. ACF were detected by methylene blue staining and subjected to quantitative morphometric analysis. Colons were then restained with high iron diamine–alcian blue for assessment of mucin depletion using an image overlay to associate morphometric data with mucin depletion. The subsequent evaluation of ACF for beta-catenin staining is also demonstrated. The methods described are particularly relevant to the screening of compounds for cancer chemopreventive activity.
Focused examination of cerebral blood flow in peri-resuscitation: a new advanced life support compliant concept—an extension of the focused echocardiography evaluation in life support examination
Authors: Haas Marco , Allendörfer Jens , Walcher Felix , Neumann-Haefelin Tobias , Blaivas Michael , Seeger Florian H. , Schreiber Stephan J. , Breitkreutz Raoul
Published: May 2010

Aim

To introduce a new concept of the extension of focused echocardiography evaluation in life support (FEEL) with advanced life support (ALS)-compliant duplex sonography of the extracranial internal carotid artery (ICA) blood flow velocity for monitoring of cerebral blood circulation during peri-resuscitation.

Concept and results

With respect to pulseless electrical activity states, the question of adequate cerebral blood flow (CBF) cannot be answered by echocardiography alone. Pulse checks are unreliable. To build up a concept for assessing CBF, we analyzed duplex sonography workflow in three adults on the intensive care unit (postoperative, cardiogenic shock, cardiac standstill), and in simulated procedures. We decided to use duplex flow velocity of the ICA, for it is an accepted measurement for estimating CBF and it seems to be easy to obtain a window and interpretation during peri-resuscitation. The presence of an arterial blood flow pattern and an end-diastolic flow velocity of more than 20 cm/s, arbitrarily set, is considered to indicate sufficient CBF. The method of ICA flow velocity analysis during peri-resuscitation was tentatively added to the FEEL concept and is described with algorithm, workflow and three cases. This method may give an assist to answer the question, if CBF is sufficient, when myocardial wall motion is detectable in peri-resuscitation care.

Conclusion

This new concept of an ALS-conformed analysis of ICA blood flow velocity by duplex sonography may provide a simple, fast applicable and inexpensive method to qualitatively assess CBF in the peri-resuscitation setting.
Nation-Building in Post-Soviet Russia: What Kind of Nationalism is Produced by the Kremlin?
Authors: Panov Petr
Published: May 2010

After collapse and subsequent dissolution of the Soviet Union, post-Soviet Russia faced typical problems of state-building and nation-building. Nations are assumed as political communities of Modernity. They are constructed in the process of nation-building and are based on nationalism, defined as worldview which perceives social reality through the prism of dividing the world into nations-states. Nation-building is a discursive process where state's activities predefine the type of nationalism being rooted. Using as a starting point ‘civic versus ethnic nationalism’ dichotomy, the article develops a transformed version of this typology, which is based on two dimensions: model of national membership (openness/closeness) and model of interaction among members (universalism/hierarchical particularism). The analysis of Annual Addresses of the Russian Presidents demonstrates that the Kremlin certainly produces open model of national membership. The key feature of ‘Russianness’ in the Kremlin discourse is commitment to the Russian culture where anyone can be recognized as ‘Russian’ as long as he/she shares the Russian cultural values. At the same time, the openness is combined with neglect of ‘civicism’. In contrast to ‘civicism’, which is based on rational notions of equal rights and responsibilities and universalistic patterns of behavior, the Kremlin image of Russian nation focuses on rather sacral idea of ‘the Russian way’, great historical mission as the destination of Russia. Openness of nationalism entails permanent expansion of the nation ‘outside itself’ in order to ‘absorb’ those groups who are able to accept Russian culture. Since the acceptance requires definite period of time, at any point of time Russian nation includes both ‘core of the nation’ and ‘aspirants’ that are in hierarchical order. Consequently, from the point of the second dimension, Russian nationalism falls into the category of hierarchical particularism.
Internal and External Dynamics of Regional Cooperation in Central Asia
Authors: Rakhimov Mirzokhid
Published: May 2010

Contemporary Central Asia in the process of transformation and facing common security challenges. The stability and security in Central Asia affected the direction of integration, patterns of regional cooperation, and building of institutions. Central Asian republics have been co-founders of regional organizations including Central Asian Cooperation Organizations (CACO), Eurasian Economic Community (EurAsEC), Commonwealth of Independent States (CIS) and Shanghai Cooperation Organization (SCO), but their effectiveness is different. Central Asian and Caucasus republics, as well as China, Iran. Pakistan, India are involved in the process of organization and harmonization of the transport arteries and communications connecting Europe and Asia, the West and the East.

There are many problems among different actors in Central Asia and Afghanistan, including Russia, US, China, the EU, NATO, OSCE and other international organizations, because they different approaches and understanding of the situation.

Challenges of the 21-century require a broader partnership and cooperation. Future prospects of multilateral regional and international cooperation in Central Asia will depend on correlations of national, regional and global interests. It is necessary first of all strong dialogs between Central Asian republics itself. Central Asian geopolitical, economic and security challenges are connected and solution could come jointly. Future regional cooperation, strong international partnership would promote more stability, economic reforms and democratization to region and beyond.
Eurasia between Cultural Studies and Marketing
Authors: Hoffmann Edgar
Published: May 2010

In marketing, Eurasia is currently still an area of terra incognita between the CEE and the Asia-pacific region. This paper deals from a linguistic cultural studies viewpoint with the question of how far Eurasia can be a relevant region for MNE marketing. To this end, the enrichment of the conception of Eurasia in Russia will be researched in its philosophical, political and economic dimensions using the original geographic dimension as a baseline. The individual conceptual components will be scrutinized in detail for their potential significance for regional marketing in post-soviet economic discourse, whereby neo-Eurasianism in contemporary Russian thinking deserves particular significance.
Molecular classification of human endometrial cancer based on gene expression profiles from specialized microarrays
Authors: Yao YuanYang , Chen YongHua , Wang Yue , Li XiaoPing , Wang JianLiu , Shen DanHua , Wei LiHui
Published: May 2010

Objective

To investigate whether the molecular classification of endometrial cancer based on gene expression profiles can predict the biological behavior of the tumors and inform prognosis.

Methods

An array containing 492 genes was used to generate gene expression profiles from 35 tumor samples. A hierarchical cluster algorithm was used to compare gene expression patterns among the tumor samples.

Results

A cluster analysis revealed 3 distinct tumor clusters. A comparative analysis of tumor type, grade, FIGO stage, and depth of myometrial invasion revealed significant differences in grade and stage among the clusters, which appear to group tumors with specific clinical behaviors. Moreover, the cluster analysis initially revealed 2 clusters of differentially expressed genes. One contained 38 genes that were upregulated in most samples of the cluster representing the most advanced disease, and the other contained 27 genes that were upregulated in most samples of the cluster representing the least advanced disease.

Conclusion

Molecular classification of endometrial cancer based on gene expression profiles obtained by designing specialized microarrays indicated a marked correspondence with the histologic features and clinical behavior of endometrial cancer tumors.
High‐grade histologic lesions in women with low‐grade squamous intraepithelial lesion cytology from a region of Thailand with a high incidence of cervical cancer
Authors: Kiatiyosnusorn Rattapon , Suprasert Prapaporn , Srisomboon Jatupol , Siriaree Sitthicha , Khunamornpong Surapan , Kietpeerakool Chumnan
Published: May 2010

Objective

To evaluate the prevalence of and predictors for underlying significant lesions in women with low‐grade squamous intraepithelial lesion (LSIL) smears.

Methods

Records were retrospectively reviewed for 208 women with LSIL who underwent colposcopy and histological evaluation from October 2004 through April 2009.

Results

Mean age of the patients was 38.5 years. Forty‐four (21.2%) women were nulliparous; 20 (9.6%) women were postmenopausal; 29 (13.9%) women tested positive for HIV. Thirty‐three (15.9%) women were current users of combined oral contraceptive pills. The pathological results of initial colposcopic evaluations were: 63 (30.3%) with cervical intraepithelial neoplasia (CIN) 2–3; 62 (29.8%) with CIN 1; 4 (1.9%) with cervical cancer; and 79 (38.0%) with no epithelial lesion. Current use of combined oral contraceptive pills, a positive HIV test, and multiparity were significant independent predictors for high‐grade disease.

Conclusion

Approximately one‐third of women with LSIL in our population have underlying significant lesions. Current use of combined oral contraceptive pills, a positive HIV test, and multiparity are significant predictors for high‐grade lesions.
On-Column Solvent Exchange for Purified Preparative Fractions
Authors: Goetz Gilles H. , Beck Emily , Tidswell Peter W.
Published: May 2010

On-column solvent exchange, using many of the principles of solid-phase extraction, has been implemented to significantly reduce evaporation cycle time following reverse-phase preparative HPLC. Additional benefits, such as a reduced potential for salt formation, thermal decomposition, and residual solvent, are also described.

Fractions obtained from preparative separations, typically in a large volume of acetonitrile:water, are injected into the preparative HPLC and then eluted in acetonitrile, creating a new fraction in a volatile organic solvent. Minimal modification to the instrument was required, and unattended operation is possible. Acetonitrile evaporation is achieved within 3 h, compared with 17 h for aqueous-based fractions; lower temperatures can be used during the evaporation step; mobile-phase additives, likely to form salts with the target compound if concentrated in the fraction, are removed before evaporation; sample recovery and purity are unaffected.
Prevalence of selected infectious agents in cats in Ireland
Authors: Juvet Florence , Lappin Michael R. , Brennan Sheila , Mooney Carmel T.
Published: May 2010

Vector-borne bacterial and rickettsial agents and Toxoplasma gondii, are common organisms in cats. Some are potentially zoonotic or may be transmitted via blood transfusion. The current study investigated the prevalence of these agents in cats from Dublin, Ireland, for which no published data exists. Whole blood ( n=116) and sera ( n=83) samples were obtained from 121 cats. DNA was extracted from blood and assayed using polymerase chain reaction techniques for Anaplasma species, Bartonella species, Ehrlichia species, Mycoplasma haemofelis, ‘ Candidatus Mycoplasma haemominutum’, ‘ Candidatus Mycoplasma turicensis’ and Rickettsia species. IgG and T gondii IgG and IgM serum antibodies were detected by enzyme-linked immunosorbent assay. DNA consistent with B henselae (3.4%), B clarridgeiae (0.8%), both Bartonella species (0.8%), C M haemominutum (12.9%), or M haemofelis (2.5%) was amplified from 24/116 blood samples (20.6%). Antibodies to T gondii and Bartonella species were detected in 28 (33.7%) and 22 (26.5%) of 83 sera, respectively.
Holocene climate variations from Zhuyeze terminal lake records in East Asian monsoon margin in arid northern China
Authors: Long Hao , Lai ZhongPing , Wang NaiAng , Li Yu
Published: May 2010

Zhuyeze palaeolake is a terminal lake situated in the arid northern China in the East Asian monsoon margin. In order to examine the Holocene palaeoclimatic change in the East Asian monsoon margin, Qingtu Lake section (QTL) from Zhuyeze palaeolake is sampled in high resolution. Palaeoclimatic proxies such as grain size, carbonate, TOC, C/N andδ13C of organic matter, were analyzed; eleven14C samples and six optically stimulated luminescence (OSL) samples were dated to provide chronological control. We also investigated the geomorphic features of lake shorelines in this area. The results show that the climate was warm and dry in early-Holocene (9.5–7.0 cal ka BP), cool and humid in mid-Holocene (7.0–4.8 cal ka BP), and increasingly drier in late-Holocene (since 4.8 cal ka BP). Comparisons of our records with other records in adjacent areas, as well as with the records in the Asian monsoon areas, suggested that changes in effective moisture was synchronous in East Asian monsoon marginal zone (i.e. the pattern of dry early-Holocene, humid mid-Holocene, and aridity-increasing late-Holocene), and that the moisture optimum during the Holocene was out-of-phase between Asian monsoon margin and Asian monsoonal dominated region, possibly due to the high temperature at that time.
Participation cues: Coordinating activity and collaboration in complex online gaming worlds
Authors: Keating Elizabeth , Sunakawa Chiho
Published: May 2010

The development of digital communication technologies not only has an influence on human communicative practices, but also creates new spaces for human collaborative activity. In this article we discuss a technologically mediated context for interaction, computer games. Closely looking at interactions among a group of gamers, we examine how players are managing complex, shifting frameworks of participation, the virtual game world and the embodied world of talk and plans for action. Introducing the notion ofparticipation cues, we explain how interactants are able to orient to, plan, and execute collaborative actions that span quite different environments with quite different types of agency, possible acts, and consequences. Novel abilities to interact across diverse spaces have consequences for understanding how humans build coordinated action through efficient, multimodal communication mechanisms. (Computer-mediated communication, language and technology, gaming, gesture, participation, multimodality)*
AN INTERVIEW WITH ROGER GUESNERIE
Authors: Chiappori Pierre-André
Published: May 2010

Roger Guesnerie is a prominent economic theorist. Among his many honors and distinctions, he is a Foreign Member of the American Academy of Arts and Science and an Honorary Foreign Member of the American Economic Association; he has been a President of the European Economic Association and of the Econometric Society. Currently a Professor at the College de France, he has made fundamental contributions to second-best theory and public economics, information economics, and rational expectation theory.

Guesnerie was one of the founding fathers of second-best theory. His contributions to public economics, addressing issues such as nonconvex economies and especially taxation in a second-best context, remain absolute references on these topics; more recently, he has provided an in-depth analysis of issues related to climate change and global warming from a public economics perspective. Regarding contract theory, his work with Jean Jacques Laffont has considerably extended our understanding of the properties of the basic models, as well as the set of tools that economists can use to address these problems. Finally, Guesnerie's work has been influential in the critical reassessment of rational expectation theory that took place over the last decades. On one hand, he has been a prominent figure in the development of so-called “sunspot” models, which reconcile the Keynesian notion of “animal spirits” with the formal requirements of rational expectations. On the other hand, he has provided path-breaking discussions of thetheoreticalrelevance of rational expectation theory, based on a detailed assessment of thecoordinationbetween individual expectations that is implicit in the concept. In some classes of models, Guesnerie argues, rational expectation equilibria constitute a natural outcome, because coordination can be achieved either through “eductive” reasoning (for which common knowledge of individual rationality is sufficient) or as the product of simple evolutionary or learning dynamics (and in general in both ways). In other cases, however, such arguments do not appear to support the rational expectations solution, and its relevance is therefore much less obvious. On a more institutional side, Guesnerie has created the doctoral program “Analyse et Politique Economique” at the Ecole des Hautes Etudes en Sciences Sociales; besides this program, in 1989, several related research centers in Paris merged into Delta, which Guesnerie chaired between 1992 and 2000, and then into the Paris School of Economics (PSE), at which Guesnerie is Chairman of the Board.

This interview with Roger Guesnerie gives an opportunity to discuss further the current situation of economic theory and economics in general, as well as to compare the European and American traditions in economics.
The role of semantics in mining frequent patterns from knowledge bases in description logics with rules
Authors: JÓZEFOWSKA JOANNA , ŁAWRYNOWICZ AGNIESZKA , ŁUKASZEWSKI TOMASZ
Published: May 2010

We propose a new method for mining frequent patterns in a language that combines both Semantic Web ontologies and rules. In particular, we consider the setting of using a language that combines description logics (DLs) with DL-safe rules. This setting is important for the practical application of data mining to the Semantic Web. We focus on the relation of the semantics of the representation formalism to the task of frequent pattern discovery, and for the core of our method, we propose an algorithm that exploits the semantics of the combined knowledge base. We have developed a proof-of-concept data mining implementation of this. Using this we have empirically shown that using the combined knowledge base to perform semantic tests can make data mining faster by pruning useless candidate patterns before their evaluation. We have also shown that the quality of the set of patterns produced may be improved: the patterns are more compact, and there are fewer patterns. We conclude that exploiting the semantics of a chosen representation formalism is key to the design and application of (onto-)relational frequent pattern discovery methods.
Risk factors for sedentary behavior in young adults: similarities in the inequalities
Authors: Fernandes F. S. , Portella A. K. , Barbieri M. A. , Bettiol H. , Silva A. A. M. , Agranonik M. , Silveira P. P. , Goldani M. Z.
Published: May 2010

Physical activity is a known protective factor, with benefits for both metabolic and psychological aspects of health. Our objective was to verify early and late determinants of physical activity in young adults. A total of 2063 individuals from a birth cohort in Ribeirão Preto, Brazil, were studied at the age of 23–25 years. Poisson regression was performed using three models: (1) early model considering birth weight, gestational age, maternal income, schooling and smoking; (2) late model considering individual’s gender, schooling, smoking and body mass index; and (3) combined (early + late) model. Physical activity was evaluated using the International Physical Activity Questionnaire, stratifying the individuals into active or sedentary. The general rate of sedentary behavior in the sample was 49.6%. In the early model, low birth weight (relative risk (RR) = 1.186, confidence interval (95%CI) 1.005–1.399) was a risk factor for sedentary activity. Female gender (RR = 1.379, 95%CI = 1.259–1.511) and poor schooling (RR = 1.126, 95%CI = 1.007–1.259) were associated with sedentary behavior in the late model. In the combined model, only female gender and participant’s schooling remained significant. An interaction between birth weight and individual’s schooling was found, in which sedentary behavior was more prevalent in individuals born with low birth weight only if they had higher educational levels. Variables of early development and social insertion in later life interact to determine an individual’s disposition to practice physical activities. This study may support the theoretical model ‘Similarities in the inequalities’, in which opposed perinatal backgrounds have the same impact over a health outcome in adulthood when facing unequal social achievement during the life-course.
Elastic isotropy of ɛ‐Fe under Earth's core conditions
Authors: Sha Xianwei , Cohen R. E.
Published: May 2010

Our first‐principles calculations show that both the compressional and shear waves of ɛ‐Fe become elastically isotropic under the Earth's inner core conditions, with the variation in sound velocities along different angles from the c axis within 1%. We computed the thermoelasticity at high pressures and temperatures from quasiharmonic linear response linear‐muffin‐tin‐orbital calculations in the generalized‐gradient approximation. The calculated anisotropic shape and magnitude at ambient temperature agree well with previous first‐principles predictions, and the anisotropic effects show strong temperature dependences. This implies that other mechanisms, rather than the preferential alignment of the ɛ‐Fe crystal along the Earth's rotation axis, account for the seismic P‐wave travel time anomalies. Either the inner core is not ɛ‐Fe, and/or the seismologically observed anisotropy is caused by inhomogeneity, i.e., multiple phases.
Full‐wave reflection of lightning long‐wave radio pulses from the ionospheric D region: Comparison with midday observations of broadband lightning signals
Authors: Jacobson Abram R. , Shao Xuan‐Min , Holzworth Robert
Published: May 2010

We are developing and testing a steep‐incidence D region sounding method for inferring profile information, principally regarding electron density. The method uses lightning emissions (in the band 5–500 kHz) as the probe signal. The data are interpreted by comparison against a newly developed single‐reflection model of the radio wave's encounter with the lower ionosphere. The ultimate application of the method will be to study transient, localized disturbances of the nocturnal D region, including those instigated by lightning itself. Prior to applying the method to study lightning‐induced perturbations of the nighttime D region, we have performed a validation test against more stable and predictable daytime observations, where the profile of electron density is largely determined by direct solar X‐ray illumination. This article reports on the validation test. Predictions from our recently developed full‐wave ionospheric‐reflection model are compared to statistical summaries of daytime lightning radiated waveforms, recorded by the Los Alamos Sferic Array. The comparison is used to retrieve best fit parameters for an exponential profile of electron density in the ionospheric D region. The optimum parameter values are compared to those found elsewhere using a narrowband beacon technique, which used totally different measurements, ranges, and modeling approaches from those of the work reported here.
Cloud properties and radiative forcing over the maritime storm tracks of the Southern Ocean and North Atlantic derived from A‐Train
Authors: Mace Gerald G.
Published: May 2010

Annually averaged cloud properties, cloud radiative effects, and cloud radiative heating from 20° × 20° latitude‐longitude regions in the Southern Ocean (50°S, 135°W) and the North Atlantic (55°N, 25°W) are compared using quantities derived from measurements collected by active and passive remote sensors in the NASA A‐Train. The algorithm suite used to infer cloud properties along the nadir track of the CloudSat and CALIPSO satellites takes input from the cloud boundaries from the merged active remote sensors, radar reflectivity from CloudSat, liquid water path derived from the Advanced Microwave Scanning Radiometer on Aqua, optical depth derived from the Moderate Resolution Imaging Spectroradiometer on Aqua, and top‐of‐atmosphere (TOA) fluxes measured by the Clouds and the Earth's Radiant Energy System. Errors in annually averaged cloud radiative effect are estimated to range from approximately 5 to 10 W m−2 and heating rate uncertainties range from 0.5 to 2 K day−1. The study regions demonstrate a high degree of similarity in cloud occurrence statistics, in cloud properties, and in the radiative effects of the clouds. Both regions are dominated by a background state of boundary layer clouds (mean liquid water path ∼150 g m−2). Boundary layer clouds and cirrus (mean ice water path ∼100 g m−2) occurring either alone or together amount to approximately 75% of all clouds. Deeper frontal clouds amount to 10%–12% of the coverage. A strong net TOA cooling effect is partitioned between solar cooling of the surface and IR cooling of the atmosphere that is dominated by the ubiquitous boundary layer clouds. It is shown that regimes inferred according to their cloud top pressure and optical depth are often dominated by multiple hydrometeor layers and therefore defy simple classification. Because of this vertical distribution, hydrometeor‐induced heating is distributed within the atmosphere in a different way than would be inferred from passive remote‐sensing data considered alone.
Assessment of ISCCP cloudiness over the Tibetan Plateau using CloudSat‐CALIPSO
Authors: Naud Catherine M. , Chen Yong‐Hua
Published: May 2010

Cloudiness over the Tibetan Plateau is difficult to estimate because ground‐based measurements are sparse. Satellite observations are thus the best tool and one of the longest climatologies available, the International Satellite Cloud Climatology Project (ISCCP), relies on passive remote sensing to characterize cloud cover and altitude. Active remote sensing from space is used to assess the accuracy of the ISCCP observations over the Tibetan Plateau. August 2006 is chosen to conduct the assessment and compared to February 2007. Cloud cover from ISCCP is underestimated by about 18%, in part because of misdetection of low‐level clouds at night. ISCCP cloud top pressures are overestimated by about 150–200 mb in August and 60–130 mb in February. However, the most accurate ISCCP cloud top pressures, with a maximum bias of about 50 mb, are obtained when there are thick single‐layer clouds. Within the region, there is no evidence that the differences are directly dependent on elevation. Problems identified in other regions, such as multilayer clouds and optically thin clouds, explain most of the discrepancies in our study region. These results indicate that ISCCP cloud retrievals can be used to compile a realistic climatology at the highest altitudes where single‐layer clouds dominate and that the retrievals are most accurate in winter.
Black carbon aerosols over an urban region: Radiative forcing and climate impact
Authors: Ramachandran S. , Kedia Sumita
Published: May 2010

Black carbon (BC) mass concentration in Ahmedabad, an urban location, varies from 2 μg m−3 during summer to 11 μg m−3 during winter and postmonsoon seasons. Aerosol optical depth (AOD) is higher (0.63) in summer when compared to winter (0.31). BC mass concentrations in Ahmedabad are governed by local sources and meteorology (boundary layer, winds, rainfall, and long‐range transport). Single‐scattering albedo (SSA) deduced using measured BC mass concentration as input in an aerosol optical properties model varies from ∼0.7 during winter and postmonsoon to 0.93 in monsoon over Ahmedabad. Surface (SFC) and atmosphere (ATM) aerosol radiative forcing (ARF) in premonsoon and monsoon are ∼50% lower than those obtained during winter and postmonsoon despite higher AODs. ATM forcing is more positive for lower SSA and AOD, while it is less positive for higher AOD and SSA. It is shown that when the amounts of BC and water vapor are high over continental regions, the net (shortwave + longwave) ATM warming will be higher. BC aerosols alone contribute on average 60% and 25% of shortwave and longwave ATM forcing. Seasonal mean heating rates are higher than 1.5 K/d in winter and postmonsoon. Heating rates including BC aerosols are at least a factor of 3 higher than when BC aerosols are absent, thus highlighting the crucial role BC aerosols play in modifying the radiation budget and climate. Thus, it is possible that BC aerosols because of their radiative and climate impacts could be contributing to the decreasing trend in rainfall over India.
Contribution of competition for light to within‐species variability in stomatal conductance
Authors: Loranty Michael M. , Mackay D. Scott , Ewers Brent E. , Traver Elizabeth , Kruger Eric L.
Published: May 2010

Sap flux (JS) measurements were collected across two stands dominated by either trembling aspen or sugar maple in northern Wisconsin. Observed canopy transpiration (EC‐obs) values derived from JS were used to parameterize the Terrestrial Regional Ecosystem Exchange Simulator ecosystem model. Modeled values of stomatal conductance (GS) were used to determine reference stomatal conductance (GSref), a proxy for GS that removes the effects of temporal responses to vapor pressure deficit (D) on spatial patterns of GS. Values of GSref were compared to observations of soil moisture, several physiological variables, and a competition index (CI) derived from a stand inventory, to determine the underlying cause of observed variability. Considerable variability in GSref between individual trees was found, with values ranging from 20 to 200 mmol m−2 s−1 and 20 to 100 mmol m−2 s−1 at the aspen and maple stands, respectively. Model‐derived values of GSref and a sensitivity to D parameter (m) showed good agreement with a known empirical relationship for both stands. At both sites, GSref did not vary with topographic position, as indicated by surface soil moisture. No relationships were observed between GSref and tree height (HT), and a weak correlation with sapwood area (AS) was only significant for aspen. Significant nonlinear inverse relationships between GSref and CI were observed at both stands. Simulations with uniform reductions in incident photosynthetically active radiation (Q0) resulted in better agreement between observed and simulated EC. Our results suggest a link between photosynthesis and plant hydraulics whereby individual trees subject to photosynthetic limitation as a result of competitive shading exhibit a dynamic stomatal response resulting in a more conservative strategy for managing hydrologic resources.
Three‐dimensional electrical resistivity image of magma beneath an active continental rift, Taupo Volcanic Zone, New Zealand
Authors: Heise Wiebke , Caldwell T. Grant , Bibby Hugh M. , Bennie Stewart L.
Published: May 2010

Magmatic activity in regions of continental extension may result in huge (>400 km3) explosive eruptions of viscous, gas‐rich silicic‐magma. Geochemical and geological data suggest that the large volumes of magma erupted are produced by extracting interstitial liquid from a long‐lived ‘mush zone’ (a mixture of solid crystals and liquid melt) that accumulates in liquid‐dominated lenses at the top of a much thicker region of lower melt‐fraction mush. Such lenses will be highly electrically conductive compared with normal mid‐crustal rocks. Here we use results of 220 magnetotelluric (MT) soundings to construct a 3‐D electrical resistivity image of the northern (silicic) part of New Zealand's Taupo Volcanic Zone, a young continental rift associated with very high heat flow and intense silicic volcanism. The electrical resistivity image shows a plume‐like structure of high conductivity, interpreted to be a zone of interconnected melt, rising from depths >35 km beneath the axis of extension.
Unexpected connections between the stratosphere and ionosphere
Authors: Goncharenko L. P. , Chau J. L. , Liu H.‐L. , Coster A. J.
Published: May 2010

The coupling of the ionosphere to processes from below remains an elusive and difficult problem, as rapidly changing external drivers from above mask variations related to lower atmospheric sources. Here we use superposition of unique circumstances, current deep solar minimum and a record‐breaking stratospheric warming event, to gain new insights into causes of ionospheric perturbations. We show large (50–150%) persistent variations in the low‐latitude ionosphere (200–1000 km) that occur several days after a sudden warming event in the high‐latitude winter stratosphere (∼30 km). We rule out solar irradiance and geomagnetic activity as explanations of the observed variation. Using a general circulation model, we interpret these observations in terms of large changes in atmospheric tides from their nonlinear interaction with planetary waves that are strengthened during sudden warmings. We anticipate that further understanding of the coupling processes with planetary waves, accentuated during the stratospheric sudden warming events, has the potential of enabling the forecast of low‐latitude ionospheric weather up to several days in advance.
Variables Associated With Communicative Participation in People With Multiple Sclerosis: A Regression Analysis
Authors: Baylor Carolyn , Yorkston Kathryn , Bamer Alyssa , Britton Deanna , Amtmann Dagmar
Published: May 2010

Purpose

To explore variables associated with self-reported communicative participation in a sample (
n
= 498) of community-dwelling adults with multiple sclerosis (MS).

Method

A battery of questionnaires was administered online or on paper per participant preference. Data were analyzed using multiple linear backward stepwise regression. The dependent variable was an item response theory score of communicative participation measured by a subset of items from the Communicative Participation Item Bank asking respondents to rate how much their health condition interfered with participation in real-life speech communication situations. Thirteen independent variables were included in the model as self-reported symptoms: problems thinking, slurred speech, vision loss, pain, mobility, depression, fatigue, perceived social support, age, education level, employment status, gender, and MS duration.

Results

Fatigue, slurred speech, depression, problems thinking, employment status, and social support were significantly associated with communicative participation, accounting for 48.7% of the variance.

Conclusions

Communicative participation is significantly associated with multiple variables, only some of which reflect communication disorders. If the goal of intervention is to improve communicative participation, intervention may need to extend beyond traditional speech-language pathology boundaries to include other health symptoms as well as personal, social, and physical environments.
Nonwords and Generalization in Children With Phonological Disorders
Authors: Gierut Judith A. , Morrisette Michele L. , Ziemer Suzanne M.
Published: May 2010

Purpose

To evaluate the effects of using nonword (NW) stimuli in treatment of children with phonological disorders relative to real words (RWs).

Methods

Production data from 60 children were examined retrospectively. Thirty of the participants were previously treated on sounds in error using NWs, and the other 30 had been treated using RWs. Generalization was the dependent variable, with measurement of accurate production of treated and untreated sounds immediately posttreatment and longitudinally following the withdrawal of treatment.

Results

Under both stimulus conditions, and at both sampling points in time, there was greater generalization to treated sounds compared with untreated. NWs, as opposed to RWs, induced greater, more rapid systemwide generalization as a function of treatment. Children exposed to NWs sustained those levels of performance even after treatment was withdrawn. Children exposed to RWs eventually reached comparable levels of phonological generalization, but not until 55 days after the cessation of treatment.

Conclusion

The findings support the ecological validity of NWs in phonological treatment. The differential results hint that NWs may benefit treatment efficacy and efficiency, but this remains to be determined through prospective study. Consideration is given to a potential theoretical account of the NW effects, with appeal to the literature on novel word learning.
Metastable phase formation during the reaction of Ni films with Si(001): The role of texture inheritance
Authors: Gaudet S. , Coia C. , Desjardins P. , Lavoie C.
Published: May 2010

The thermally induced solid-state reaction between a 10-nm-thick Ni film and a Si(001) substrate was investigated using in situ x-ray diffraction and ex situ pole figure analyses. The reaction begins with the appearance of orthorhombic Ni2Si grains characterized by a strong fiber texture. The formation of the metastable hexagonal θ phase—which inherits the fiber texture of Ni2Si—is then observed. This phase has been observed in every sample studied regardless of dopant, film thickness, deposition method, and anneal profile (>2000 conditions). Texture inheritance allows a reaction pathway with a lower activation energy than the expected formation through thermodynamically stable Ni silicide phases.
Two sources of cross-field error in racetrack fluxgate
Authors: Janosek M. , Butta M. , Ripka P.
Published: May 2010

This contribution covers cross-field response of fluxgate sensors with a flat, single-sheet race-track core, which to our knowledge has not been studied yet. In the case of race-track shape, it was commonly believed that the error is automatically lower than for the ringcore due to the shape anisotropy. Instead we observed that the exact geometry of the race track (i.e., ratio between the longitudinal and upright section) and the position of the coils start to play a significant role, not only the core homogeneity—there is no more symmetry as in the case of a ring core. We found the cross-field response dependent on defining the perpendicular angle, either to the sensor’s core axis or to the axis of the feedback coil; these two axes were misaligned by up to 1°. When arranging the cross field to be perpendicular to the feedback coil axis, we were able to verify results previously published in literature: we obtained 60 nT response for 50 μT cross-field.
Prediction method of flux loss in anisotropic NdFeB/SmFeN hybrid magnets
Authors: Fukunaga Hirotoshi , Murata Hiroki , Yanai Takeshi , Nakano Masaki , Yamashita Fumitoshi
Published: May 2010

We systematically evaluated the initial flux loss of anisotropic HDDR-NdFeB/RD-SmFeN hybrid bonded magnets. The measured flux loss values were compared with those obtained by two prediction methods based on our previous proposal. Consequently, it was clarified that the initial flux loss of anisotropic bonded magnets can be predicted from demagnetization curves at room and exposure temperatures of the corresponding hybrid magnets, which suggests that the method proposed previously for isotropic magnets can be also applicable to anisotropic ones.
Size selected synthesis of CoFe2O4 nanoparticles prepared in a chitosan matrix
Authors: Gurgel A. L. , Soares J. M. , Chaves D. S. , Chaves D. S. , Xavier M. M. , Morales M. A. , Baggio-Saitovitch E. M.
Published: May 2010

In this paper we report the synthesis and magnetic properties of CoFe2O4 nanoparticles. The nanoparticles with sizes ranging from 6 to 20 nm were prepared in a chitosan matrix. Size selection was achieved by introducing a nonionic surfactant Tween-X, where X={20, 60, 80, and 85}. Aqueous dispersions of Tween-X show micelles with increasing hydrodynamic sizes as X increases. Mössbauer spectroscopy measurements at 300 K show superparamagnetic behavior for the small particles, changing gradually to a blocked magnetic regime as the particle size increases. Magnetization measurements at 300 K show increasing values for the ratio Mr/MHmax and coercive fields (Hc).
Synthesis and tuning the exchange bias in Ni–NiO nanoparticulate systems
Authors: Sharma S. K. , Vargas J. M. , Knobel M. , Pirota K. R. , Meneses C. T. , Kumar Shalendra , Lee C. G. , Pagliuso P. G. , Rettori Carlos
Published: May 2010

We report studies on exchange bias effects in Ni–NiO nanoparticles with different particle diameters/distributions and concentration of metallic nickel, which vary from 0% to 32%. The exchange bias field, Hex, depends strongly upon both particle size and the concentration of metallic Ni, being maximum (∼2.2 kOe) at 5 K for the sample with almost negligible concentration of metallic Ni, whereas the corresponding value for the sample with highest concentration of metallic Ni (∼32±5.0%) is about 0.07 kOe. The structural features of the samples have been investigated thoroughly by using the Reitveld refinement of x-ray diffraction data and high resolution transmission electron microscopy, where as the magnetic properties using superconducting quantum interference device magnetometer.