bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diversity of ammonium‐oxidizing bacteria in a granular sludge anaerobic ammonium‐oxidizing (anammox) reactor
Authors: Quan Zhe‐Xue , Rhee Sung‐Keun , Zuo Jian‐E , Yang Yang , Bae Jin‐Woo , Park Ja Ryeong , Lee Sung‐Taik , Park Yong‐Ha 
Published: May 2008

SummaryThe ammonium‐oxidizing microbial community was investigated in a granular sludge anaerobic ammonium‐oxidizing (anammox) reactor that was operated for about 1 year with high anaerobic ammonium oxidation activity (up to 0.8 kg NH4+‐N m−3 day−1). A Planctomycetales‐specific 16S rRNA gene library was constructed to analyse the diversity of the anaerobic ammonium‐oxidizing bacteria (AnAOB). Most of the specifically amplified sequences (15/16) were similar to each other (> 99%) but were distantly related to all of the previously recognized sequences (< 94%), with the exception of an unclassified anammox‐related clone, KSU‐1 (98%). An ammonia monooxygenase (amoA) gene library was also analysed to investigate the diversity of ‘aerobic’ ammonium‐oxidizing bacteria (AAOB) from the β‐Proteobacteria. Most of the amoA gene fragments (53/55) clustered in the Nitrosomonas europaea–Nitrosococcus mobilis group which has been reported to prevail under oxygen‐limiting conditions. The quantitative results from real‐time polymerase chain reaction (PCR) amplification showed that the dominant AnAOB comprised approximately 50% of the total bacterial 16S rRNA genes in the reactor, whereas the AAOB of β‐Proteobacteria represented only about 3%. A large fragment (4008 bp) of the rRNA gene cluster of the dominant AnAOB (AS‐1) in this reactor sludge was sequenced and compared with sequences of other Planctomycetales including four anammox‐related candidate genera. The partial sequence of hydrazine‐oxidizing enzyme (hzo) of dominant AnAOB was also identified using new designed primers. Based on this analysis, we propose to tentatively name this new AnAOB Candidatus‘Jettenia asiatica’.
Responses of Antarctic soil microbial communities and associated functions to temperature and freeze–thaw cycle frequency
Authors: Yergeau Etienne , Kowalchuk George A. 
Published: May 2008

SummaryClimatic changes will not only result in higher overall temperature, but also in greater variability in weather conditions. Antarctic soils are subjected to extremely variable conditions in the form of frequent freeze–thaw cycles (FTCs), but the importance of alteration in FTC frequency, compared with increases in average temperature and indirect vegetation‐mediated effects on soil microorganisms, is still unknown. We therefore designed two complementary microcosm experiments using undisturbed soil cores from Signy Island (60°43′S, 45°38′W) in the maritime Antarctic. The experiments consisted of soil core incubations with or without the overlying vegetation at four different temperatures and six different FTC regimes. We assessed bacterial and fungal density and community structure, as well as the density of several key genes in microbial nutrient cycles using a combination of RNA‐ and DNA‐based molecular fingerprinting and quantitative PCR approaches in addition to enzymatic activity assays. Results showed that bacteria were more affected by warming than by changes in FTC frequency. In contrast, fungal community structure and abundance were mostly influenced by FTC frequency, as well as the presence of vegetation cover. The relative densities of several bacterial gene families involved in key steps of the N‐cycle were affected by FTCs, while warming had little or no effect. The FTCs and incubation temperature also strongly influenced laccase enzymatic activity in soil. In total, our results suggest that, in addition to climatic warming, increased climatic variability may also have a profound impact on Antarctic microbial communities. Although these effects are difficult to detect with assays of total bacterial community structure, they do become manifest in the analysis of key functional gene densities.
Viral communities associated with healthy and bleaching corals
Authors: Marhaver Kristen L. , Edwards Robert A. , Rohwer Forest 
Published: May 2008

SummaryThe coral holobiont is the integrated assemblage of the coral animal, its symbiotic algae, protists, fungi and a diverse consortium of Bacteria and Archaea. Corals are a model system for the study of symbiosis, the breakdown of which can result in disease and mortality. Little is known, however, about viruses that infect corals and their symbionts. Here we present metagenomic analyses of the viral communities associated with healthy and partially bleached specimens of the Caribbean reef‐building coral Diploria strigosa. Surprisingly, herpes‐like sequences accounted for 4–8% of the total sequences in each metagenome; this abundance of herpes‐like sequences is unprecedented in other marine viral metagenomes. Viruses similar to those that infect algae and plants were also present in the coral viral assemblage. Among the phage identified, cyanophages were abundant in both healthy and bleaching corals and vibriophages were also present. Therefore, coral‐associated viruses could potentially infect all components of the holobiont – coral, algal and microbial. Thus, we expect viruses to figure prominently in the preservation and breakdown of coral health.
Elective (planned) colectomy in patients with colorectal obstruction after placement of a self‐expanding metallic stent as a bridge to surgery: the results of a prospective study
Authors: Brehant O. , Fuks D. , Bartoli E. , Yzet T. , Verhaeghe P. , Regimbeau J. M. 
Published: May 2008

AbstractIntroduction  Acute malignant colorectal obstruction (CRO) can be satisfactorily dealt by the placement of a self‐expanding metallic stent (SEMS). The aim of this prospective study was to evaluate the rate of elective (planned) colectomy (EPC) in patients with CRO after SEMS placement as a bridge to surgery on an intention‐to‐treat (ITT) basis.Method  From 2002 to 2007, 30 SEMS were placed as a bridge to surgery in 30 CRO patients (median age 73 ± 12 years). The obstructing lesions were located in the right (n = 1), transverse (n = 1) or left colon (n = 24) or the upper third of the rectum (n = 4).Results  The SEMS was placed successfully in 25 (83%) patients. Five patients underwent Hartmann’s procedure (n = 2) or a diverting colostomy (n = 3). The SEMS was functionally operational in 23 (92%) of the 25 patients. A diverting colostomy was avoided in 23 (77%) of the 30 patients (placement failure n = 5, clinical failure n = 2). There were no complications in 17 (80%) patients. On an ITT basis, 70% of the patients (21 out of 30) underwent an EPC.Conclusion  On an ITT basis, SEMS placement in CRO patients enabled EPC in 70% of patients.
Comparative performance of UK mutual building societies and stock retail banks: further evidence
Authors: Shiwakoti Radha K. , Keasey Kevin , Hudson Robert 
Published: May 2008

AbstractThe purpose of this paper is to extend the literature on the comparative performance of mutual and stock retail banks by examining a unique episode in the history of financial services; namely, when four of the largest UK building societies (accounting for approximately 60 per cent of the industry's assets) demutualized to public limited company status in 1997. The episode allows us to consider the relative performance of the same businesses under different organizational forms. The results contrast starkly with previous findings and cast doubt on the hypothesis that mutuals generally outperform stock retail banks and indeed the idea that mutuals can be regarded as a homogeneous group of institutions.
Students as designers and creators of educational computer games: Who else?
Authors: Prensky Marc 
Published: May 2008

AbstractIn the companion article, Spirit of the Game: Empowering Students as Designers in Schools?, author Cher Ping Lim puts forth strong arguments supporting the creation and use of curricular, educational games in our schools and education. His essay ends with the question ‘Can students build such games?’ This paper responses to this question and provides examples of how students can design and build games within the school curriculum to enhance engagement in the classrooms. Two approaches are suggested: Mini‐game‐based curriculum and complex game for entire course.
The impact of mobile learning on students' learning behaviours and performance: Report from a large blended classroom
Authors: Wang Minjuan , Shen Ruimin , Novak Daniel , Pan Xiaoyan 
Published: May 2008

AbstractChinese classrooms, whether on school grounds or online, have long suffered from a lack of interactivity. Many online classes simply provide recorded instructor lectures, which only reinforces the negative effects of passive nonparticipatory learning. At Shanghai Jiaotong University, researchers and developers actively seek technologic interventions that can greatly increase interactivity in large blended classes. They developed a cutting‐edge mobile learning system that can deliver live broadcasts of real‐time classroom teaching to students with mobile devices. Their system allows students to customise means of content‐reception based on when and where they tune into the broadcast. The system also supports short text messaging and instant polls. Through these venues, students can ask questions and make suggestions in real time, and the instructor can address them immediately. This article describes this system in detail, and also reports results from a formal implementation of the system in a blended English classroom of 1000 students (with about 800 being online). As the data reveal, m‐learning activities can much better engage students in the learning process. Students in this class changed from passive learners to truly engaged learners who are behaviourally, intellectually and emotionally involved in their learning tasks.
Multimedia learning and individual differences: Mediating the effects of working memory capacity with segmentation
Authors: Lusk Danielle L. , Evans Amber D. , Jeffrey Thomas R. , Palmer Keith R. , Wikstrom Chris S. , Doolittle Peter E. 
Published: May 2008

AbstractResearch in multimedia learning lacks an emphasis on individual difference variables, such as working memory capacity (WMC). The effects of WMC and the segmentation of multimedia instruction were examined by assessing the recall and application of low (n=66) and high (n=67) working memory capacity students randomly assigned to either a segmented instruction (SI) or non‐segmented instruction (NSI) version of a multimedia tutorial on historical inquiry. WMC was found to have a significant, positive effect on participants' recall and application scores; however, the use of segmentation mediated the effects of WMC to allow learners with lower WMC to recall and apply equal to those with higher WMC.
The youngest blueschist belt in SW Japan: implication for the exhumation of the Cretaceous Sanbagawa high‐P/T metamorphic belt
Authors: AOKI K. , ITAYA T. , SHIBUYA T. , MASAGO H. , KON Y. , TERABAYASHI M. , KANEKO Y. , KAWAI T. , MARUYAMA S. 
Published: May 2008

AbstractThe tectonic evolution of the Northern Shimanto belt, central Shikoku, Japan, was examined based on petrological and geochronological studies in the Oboke area, where mafic schists of the Kawaguchi Formation contain sodic amphibole (magnesioriebeckite). The peak P–T conditions of metamorphism are estimated as 4–4.5 kbar (15–17 km depth), and 240–270 °C based on available phase equilibria and sodic amphibole compositions. These metamorphic conditions are transitional between blueschist, greenschist and pumpellyite–actinolite facies. Phengite K–Ar ages of 64.8 ± 1.4 and 64.4 ± 1.4 Ma were determined for the mafic schists, and 65.0 ± 1.4, 61.4 ± 1.3 and 63.6 ± 1.4 Ma for the pelitic schists. The metamorphic temperatures in the Oboke area are below the closure temperature of the K–Ar phengite system, so the K–Ar ages date the metamorphic peak in the Northern Shimanto belt. In the broad sense of the definition of blueschist facies, the highest‐grade part of the Northern Shimanto belt belongs to the blueschist facies. Our study and those of others identify the following constraints on the possible mechanism that led to the exhumation of the overlying Sanbagawa belt: (i) the Sanbagawa belt is a thin tectonic slice with a structural thickness of 3–4 km; (ii) within the belt, metamorphic conditions varied from 5 to 25 kbar, and 300 to 800 °C, with the grade of metamorphism decreasing symmetrically upward and downward from a structurally intermediate position; and (iii) the Sanbagawa metamorphic rocks were exhumed from ∼60 km depth and emplaced onto the Northern Shimanto metamorphic rocks at 15–17 km depth and 240–270 °C. Integration of these results with those of previous geological studies for the Sanbagawa belt suggests that the most probable exhumation mechanism is wedge extrusion.
The Cost of Screening Adolescents for Overweight and Hypertension Using a Community Partnership Model
Authors: Brosnan Christine A. , Swint J. Michael , Upchurch Sandra L. , Meininger Janet C. , Johnson Gwen , Lee Yu F. , Nguyen Thong Q. , Eissa Mona A. 
Published: May 2008

ABSTRACT Objectives:(1) Determine the prevalence of overweight and high blood pressure (BP) among middle and high school students over a 2‐year period and, (2) measure the cost and initial outcomes of screening.Design:Cost and outcome description using a cross‐sectional design sample. The target population was 12‐ to 19‐year‐old healthy students attending grades 7 through 12 at 3 proximal schools located in a large urban school district in Texas.Results:Of 2,338 students screened, 925 (39.6%) had a body mass index (BMI)≥85th percentile and 504 (21.6%) had BMIs≥95th percentile for age and gender. There were 346 students (14.8%) with BMIs≥85th percentile and systolic blood pressure (SBP)≥95th percentile for age, gender, and height. The cost of the 2‐year screening program was $66,442, and the cost per student was $28. The cost to identify a student with increased BMI or high SBP was $72 and $107, respectively.Conclusions:This study offered an objective framework to examine the cost and outcomes of screening children for overweight and increased BP. The study has implications for discussion and informed decision making about school‐based screening for these conditions.
Differences in Psychosocial Factors Among Novice, Experienced, and Veteran Health Promotion Volunteers in Japan
Authors: Murayama Hiroshi , Taguchi Atsuko , Murashima Sachiyo 
Published: May 2008

ABSTRACT
Objective: To examine differences in psychosocial factors among health promotion volunteers (HPVs) according to years of experience.Design: Cross‐sectional survey.Sample: A total of 604 HPVs in Koka and Konan cities in Japan in 2005.Measurements: Demographic data, extent of HPV activity (such as years of HPV experience), and psychosocial factors such as overall activity satisfaction, burden of HPV activities, and social support.Results: Compared with HPVs with 1–3 years of experience, those with 4–8 years of experience indicated that the head of the neighborhood association failed to recognize their role and lacked knowledge of HPV activity content, but that they felt greater support from community members. Those with 9 or more years of experience had more managerial experience, were more highly motivated at the end of the HPV training course, and indicated greater support from community members than those with 1–3 years of experience.Conclusions: When considering the constellation of HPV activities; the ways in which these activities are performed; and the strategies to recruit, train, support, and retain HPVs; it may be important to take into account the differences among HPVs by years of experience.
Attack Frequency and Disease Duration as Indicators for Brain Damage in Migraine
Authors: Schmitz Nicole , Admiraal‐Behloul Faiza , Arkink Enrico B. , Kruit Mark C. , Schoonman Guus G. , Ferrari Michel D. , Van Buchem Mark A. 
Published: May 2008

Objective.— The aim of this study was to pinpoint predilection sites of brain damage in migraine by quantitatively identifying morphometric and diffusion differences in migraineurs, compared with control subjects, and to assess whether migraine attack frequency and attack history are indicators for brain abnormalities in migraineurs.Background.— Previous clinical neuroimaging investigations introduced the concept of migraine as a progressive brain disease. They reported an increased risk of white matter hyperintensities (WMH) with increasing attack frequency in migraineurs.Methods.— We investigated 28 patients with migraine, using high‐resolution T1‐ and diffusion‐weighted magnetic resonance imaging and optimized voxel‐based morphometry to localize gray and WM density, and fractional anisotropy and apparent diffusion coefficient differences.Results.— We identified predilection sites of brain abnormalities in migraineurs in the frontal lobes, brainstem, and the cerebellum, and we show that both attack frequency and disease duration are indicators for brain damage in migraine.Conclusion.— Our findings report an unbiased quantitative whole brain assessment of morphological abnormalities in migraine. This might help to identify indicators for migraine as a possibly progressive brain disease. In order to reveal the causes and consequences of brain damage in migraine, further neuroimaging studies have to investigate quantitative brain changes in a longitudinal design.
Interictal high‐frequency oscillations (80–500 Hz) are an indicator of seizure onset areas independent of spikes in the human epileptic brain
Authors: Jacobs Julia , LeVan Pierre , Chander Rahul , Hall Jeffery , Dubeau François , Gotman Jean 
Published: May 2008

SummaryPurpose:  High‐frequency oscillations (HFOs) known as ripples (80–250 Hz) and fast ripples (250–500 Hz) can be recorded from macroelectrodes inserted in patients with intractable focal epilepsy. They are most likely linked to epileptogenesis and have been found in the seizure onset zone (SOZ) of human ictal and interictal recordings. HFOs occur frequently at the time of interictal spikes, but were also found independently. This study analyses the relationship between spikes and HFOs and the occurrence of HFOs in nonspiking channels.Methods:  Intracerebral EEGs of 10 patients with intractable focal epilepsy were studied using macroelectrodes. Rates of HFOs within and outside spikes, the overlap between events, event durations, and the percentage of spikes carrying HFOs were calculated and compared according to anatomical localization, spiking activity, and relationship to the SOZ.Results:  HFOs were found in all patients, significantly more within mesial temporal lobe structures than in neocortex. HFOs could be seen in spiking as well as nonspiking channels in all structures. Rates and durations of HFOs were significantly higher in the SOZ than outside. It was possible to establish a rate of HFOs to identify the SOZ with better sensitivity and specificity than with the rate of spikes.Discussion:  HFOs occurred to a large extent independently of spikes. They are most frequent in mesial temporal structures. They are prominent in the SOZ and provide additional information on epileptogenicity independently of spikes. It was possible to identify the SOZ with a high specificity by looking at only 10 min of HFO activity.
The Market for Mergers and the Boundaries of the Firm
Authors: RHODES‐KROPF MATTHEW , ROBINSON DAVID T. 
Published: May 2008

ABSTRACTWe relate the property rights theory of the firm to empirical regularities in the market for mergers and acquisitions. We first show that high market‐to‐book acquirers typically do not purchase low market‐to‐book targets. Instead, mergers pair together firms with similar ratios. We then build a continuous‐time model of investment and merger activity combining search, scarcity, and asset complementarity to explain this like buys like result. We test the model by relating like‐buys‐like to search frictions. Search frictions and assortative matching vary inversely, supporting the model over standard explanations.
The Price of Immediacy
Authors: CHACKO GEORGE C. , JUREK JAKUB W. , STAFFORD ERIK 
Published: May 2008

ABSTRACTThis paper models transaction costs as the rents that a monopolistic market maker extracts from impatient investors who trade via limit orders. We show that limit orders are American options. The limit prices inducing immediate execution of the order are functionally equivalent to bid and ask prices and can be solved for various transaction sizes to characterize the market maker's entire supply curve. We find considerable empirical support for the model's predictions in the cross‐section of NYSE firms. The model produces unbiased, out‐of‐sample forecasts of abnormal returns for firms added to the S&P 500 index.
Loan Sales and Relationship Banking
Authors: PARLOUR CHRISTINE A. , PLANTIN GUILLAUME 
Published: May 2008

ABSTRACTFirms raise money from banks and the bond market. Banks sell loans in a secondary market to recycle their funds or to trade on private information. Liquidity in the loan market depends on the relative likelihood of each motive for trade and affects firms' optimal financial structure. The endogenous degree of liquidity is not always socially optimal: There is excessive trade in highly rated names, and insufficient liquidity in riskier bonds. We provide testable implications for prices and quantities in primary and secondary loan markets, and bond markets. Further, we posit that risk‐based capital requirements may be socially desirable.
Hypertrophic Cardiomyopathy with Preexcitation: Insights from Noninvasive Electrocardiographic Imaging (ECGI) and Catheter Mapping
Authors: GHOSH SUBHAM , AVARI JENNIFER N. , RHEE EDWARD K. , WOODARD PAMELA K. , RUDY YORAM 
Published: May 2008

Introduction: Fasciculoventricular pathway has been described as an unusual variant of preexcitation. Electrocardiographic imaging (ECGI) is a novel imaging modality for noninvasive electroanatomic mapping of epicardial activation and repolarization.
Case: We present a case of an 18‐year‐old male with hypertrophic cardiomyopathy (HCM) and an electrocardiogram (ECG)‐based diagnosis of Wolff‐Parkinson‐White (WPW) syndrome, who underwent a noninvasive ECGI study to image ventricular activation, followed by an electrophysiology study (EPS). The ECGI electroanatomic isochrone map showed early activation of the epicardial aspect of the atrioventricular (A‐V) groove and an aberrant posterior‐base‐to‐apex progression of activation in the left ventricular (LV) epicardium. The EPS showed a likely fasciculoventricular pathway (FVP) without any inducible tachycardia.
Conclusion: While FVP has been described before, this is the first report of detailed quantitative three‐dimensional characterization of electrical activation sequence of a heart with this type of preexcitation, using a novel noninvasive imaging modality (ECGI). In spite of abnormal ventricular activation, the EPS demonstrated that the FVP is not capable of supporting reentrant supraventricular tachycardia or rapidly conducted atrial fibrillation.