bluuebunny/crossref_metadata_2025 huggingface dataset:
Vancomycin-Related Eosinophilic Peritonitis
Authors: Rosner Mitchell H. , Chhatkuli Bed
Published: December 2010

Eosinophilic peritonitis (EP) is a well-described complication of peritoneal dialysis and is often associated with either a reaction to a constituent of the dialysis system (tubing, sterilant, or solution) or an underlying bacterial or fungal reaction. EP has also been described in the setting of icodextrin use. We report a case of EP associated with intraperitoneal vancomycin used in the treatment of peritonitis secondary to methicillin-resistant Staphylococcus epidermidis. Causation was based upon temporal association, negative cultures, concomitant peripheral eosinophilia, and resolution with cessation of vancomycin. Vancomycin allergy should be considered in the differential diagnosis of EP in the right clinical context. Negative bacterial and fungal cultures are essential to exclude other etiologies.
Tandem catalysis of ring-closing metathesis/atom transfer radical reactions with homobimetallic ruthenium–arene complexes
Authors: Borguet Yannick , Sauvage Xavier , Zaragoza Guillermo , Demonceau Albert , Delaude Lionel
Published: December 2010

The tandem catalysis of ring-closing metathesis/atom transfer radical reactions was investigated with the homobimetallic ruthenium–indenylidene complex [(p-cymene)Ru(μ-Cl)3RuCl(3-phenyl-1-indenylidene)(PCy3)] (1) to generate active species in situ. The two catalytic processes were first carried out independently in a case study before the whole sequence was optimized and applied to the synthesis of several polyhalogenated bicyclic γ-lactams and lactones from α,ω-diene substrates bearing trihaloacetamide or trichloroacetate functionalities. The individual steps were carefully monitored by 1H and 31P NMR spectroscopies in order to understand the intimate details of the catalytic cycles. Polyhalogenated substrates and the ethylene released upon metathesis induced the clean transformation of catalyst precursor 1 into the Ru(II)–Ru(III) mixed-valence compound [(p-cymene)Ru(μ-Cl)3RuCl2(PCy3)], which was found to be an efficient promoter for atom transfer radical reactions under the adopted experimental conditions.
L'idée d'une science sociale et sa relation à la science politique
Authors: Dupret Baudouin , Ferrié Jean-Noël
Published: December 2010

Résumé À partir de la publication de la traduction française d’un ouvrage de Peter Winch, l’article revient sur la tendance de la science politique et, plus largement, des sciences sociales à adopter le point de vue naturaliste selon lequel les phénomènes dont elles traitent existeraient indépendamment du point de vue des membres de la société engagés dans leur production. En ce sens, les positions opposées de Bruno Latour et de Pierre Favre, publiées dans les numéros 58 (4) et (5) de la RFSP , s’avèrent semblables : elles postulent que l’on peut déterminer ce qui est et n’est pas politique de manière externe à des pratiques précises.
Joueuse de rugby de première division : une activité dangereuse ?
Authors: Joncheray Hélène , Tlili Haïfa
Published: December 2010

Résumé Cette étude se base sur 197 questionnaires de joueuses de rugby de première division. Le sujet est celui du rugby féminin et de la dangerosité. Ces deux thématiques sont souvent associées. À la simple évocation de la pratique du rugby par des femmes, de nombreux individus pensent au danger. Si certains résultats n’incitent pas à la pratique de ce sport (75 % des joueuses disent avoir été blessées), des explications sont à rechercher sur le plan social. Luc Collard nous met sur la piste en avançant que la violence est perçue comme d’autant plus importante que « la perception du risque dans un sport donné est inversement proportionnelle à la maîtrise que l’on en a. Plus on est expert, moins le sport où l’on excelle paraît périlleux. Plus on est incompétent, moins le sport que l’on découvre paraît sécurisant » (Collard, 1998). De plus, il semblerait que la violence, qui reste une composante centrale de la pratique masculine (Elias & Dunning, 1986), ne s’exprime pas, dans le cas d’une pratique féminine, d’une manière qui soit socialement acceptable, comme si la tension autorisée chez les femmes était moindre.
Comment devient-on dirigeante d'une association sportive locale ? Des processus de transmission à l'œuvre en lien avec les rapports sociaux de sexe
Authors: Tatu-Colasseau Anne , Vieille Marchiset Gilles
Published: December 2010

Résumé L’article a pour but l’élaboration d’une typologie de dirigeantes dans l’administration du sport local afin de rendre intelligible la diversité rencontrée et de produire un outil de comparaison synchronique et diachronique pour des recherches sur la même thématique. En nous appuyant sur une enquête régionale qualitative – entretiens collectifs et seize récits de vie –, nous restituons et interprétons les traits de quatre profils types de dirigeante en nous arrêtant particulièrement sur les rapports sociaux de sexe et les processus de transmission qui les façonnent : la dirigeante de circonstance, l’élue, la militante associative et la passionnée d’une discipline sportive. Chacune révèle un positionnement différencié dans la division sexuelle du travail opérante au sein de la direction sportive. Les différents profils suggèrent que la position des dirigeantes dépend des valeurs, des normes et des savoirs transmis dans différents contextes familiaux, professionnels et sportifs. Si les deux premiers profils confirment une forme de reproduction de l’ordre social masculin, les deux autres témoignent de transformation des effets de genre et de leur traduction en matière d’investissement féminin. Ils suggèrent des changements minoritaires mais en devenir dans la direction sportive.
Study to Investigate Learning Motivation Factors within Formal and Informal Learning Environments and their influence upon Web-Based Learning
Authors: Riaz Sadia , Rambli Dayang Rohaya , Salleh Rohani , Mushtaq Arif
Published: December 2010

Learning is a cognitive process that occurs either

in a formal or informal learning environment, by way of

adopting either formal or informal learning process. While

the significance of former has been widely accepted, later is

still researched and lacks relevant studies on its implications

for web-based learning, especially by way of instigating

learning motivation. This paper presents descriptive analysis

of learning motivation factors within (i) formal and informal

learning environments, and (ii) formal and informal

learning processes, and then examines their influence on

web-based learning by computing Pearson correlations. To

achieve study objectives, the paper discusses relevant literature

and then conceptualizes a research model to be tested

through a survey based questionnaire. Formal learning

process is discussed with reference to learning activities as

promoted by formal learning institutes, while informal

learning process is examined by way of investigating learning

motivation factors associated with (i) video-games, (ii)

social networking websites and (iii) motion-pictures. Results

illustrate interesting revelation of learning motivational

factors, particularly motivational factors associated with

informal learning environment and processes have been

found to have a statistically significant relationship with

web-based learning. The paper concludes implications of the

statistical findings for designing of cognitively engaging

web-based learning environments.
myCourse: An Educational Content Management Platform with Social Networking Characteristics
Authors: Giouvanakis Thanasis , Fragidis Garyfallos , Ignatiadis Ioannis , Koumpis Adamantios
Published: December 2010

We adopt the direction towards new educational and pedagogic paradigms, where learning is a process of emergence and co-evolution of the individual, the social group and the wider society. In this direction, Service-Oriented Architectures are becoming a popular system paradigm for e-learning. In this article, we present our research and development efforts to provide a social networking learning platform for developing services which address the personal learning needs of the users and enable them to create value. We also present the specific characteristics of our community driven service framework and discuss our approach in comparison to other similar approaches and frameworks.
Emerging Communication Technology and Examination Malpractices in Nigerian Educational Sector
Authors: Adeoye Olufemi Sunday
Published: December 2010

The breakthrough in communication technology, especially that of GSM phones, in Nigeria is one of the best things that has happened to the nation in terms of its technological advancement. In Nigeria, GSM means Telecom Explosion. The GSM revolution began in August 2001 and changed the face of Information and Communications Technology in Nigeria. It is much easier to reach anybody that you have his / her number, whether they are in the village or in their closet unless in a place where there is no network of the service provider. As revolutionary as GSM may seem to be, its negative effect on our educational sector is of great concern. The ongoing war against examination malpractice is yet to take its toll on perpetrators as they have devised a new method to continue their game through the cell phone technology. Described as e-cheating, the cell phone technology is providing students a smart way to beat the best effort of stakeholders to stamp out the menace. This paper examines GSM technology, the various ways in which cell phones are employed to cheat and suggestions on how to stop e-cheating through cell phones.
Targeting the OB‐Folds of Replication Protein A with Small Molecules
Authors: Anciano Granadillo Victor J. , Earley Jennifer N. , Shuck Sarah C. , Georgiadis Millie M. , Fitch Richard W. , Turchi John J.
Published: December 2010

Replication protein A (RPA) is the main eukaryotic single‐strand (ss) DNA‐binding protein involved in DNA replication and repair. We have identified and developed two classes of small molecule inhibitors (SMIs) that show in vitro inhibition of the RPA‐DNA interaction. We present further characterization of these SMIs with respect to their target binding, mechanism of action, and specificity. Both reversible and irreversible modes of inhibition are observed for the different classes of SMIs with one class found to specifically interact with DNA‐binding domains A and B (DBD‐A/B) of RPA. In comparison with other oligonucleotide/oligosaccharide binding‐fold (OB‐fold) containing ssDNA‐binding proteins, one class of SMIs displayed specificity for the RPA protein. Together these data demonstrate that the specific targeting of a protein‐DNA interaction can be exploited towards interrogating the cellular activity of RPA as well as increasing the efficacy of DNA‐damaging chemotherapeutics used in cancer treatment.
Recent Development of Bifunctional Small Molecules to Study Metal‐Amyloid‐β Species in Alzheimer′s Disease
Authors: Braymer Joseph J. , DeToma Alaina S. , Choi Jung-Suk , Ko Kristin S. , Lim Mi Hee
Published: December 2010

Alzheimer′s disease (AD) is a multifactorial neurodegenerative disease related to the deposition of aggregated amyloid‐β (Aβ) peptides in the brain. It has been proposed that metal ion dyshomeostasis and miscompartmentalization contribute to AD progression, especially as metal ions (e.g., Cu(II) and Zn(II)) found in Aβ plaques of the diseased brain can bind to Aβ and be linked to aggregation and neurotoxicity. The role of metal ions in AD pathogenesis, however, is uncertain. To accelerate understanding in this area and contribute to therapeutic development, recent efforts to devise suitable chemical reagents that can target metal ions associated with Aβ have been made using rational structure‐based design that combines two functions (metal chelation and Aβ interaction) in the same molecule. This paper presents bifunctional compounds developed by two different design strategies (linkage or incorporation) and discusses progress in their applications as chemical tools and/or potential therapeutics.
Ultrastructure of Sheep Primordial Follicles Cultured in the Presence of Indol Acetic Acid, EGF, and FSH
Authors: Andrade Evelyn Rabelo , Maddox-Hyttel Poul , Landim-Alvarenga Fernanda Da Cruz , Viana Silva José Roberto , Alfieri Amauri Alcindo , Seneda Marcelo Marcondes , Figueiredo José Ricardo , Toniolli Ricardo
Published: December 2010

The aim of this study was to investigate the ultrastructural characteristics of primordial follicles after culturing of sheep ovarian cortical slices in the presence of indol acetic acid (IAA), Epidermal Growth Factor (EGF), and FSH. To evaluate ultrastructure of primordial follicles cultured in MEM (control) or in MEM containing IAA, EGF, and FSH, fragments of cultured tissue were processes for transmission electron microscopy. Except in the control, primordial follicles cultured in supplemented media for 6 d were ultrastructurally normal. They had oocyte with intact nucleus and the cytoplasm contained heterogeneous-sized lipid droplets and numerous round or elongated mitochondria with intact parallel cristae were observed. Rough endoplasmic reticulum (RER) was rarely found. The granulosa cells cytoplasm contained a great number of mitochondria and abundant RER. In conclusion, the presence of IAA, EGF, and FSH helped to maintain ultrastructural integrity of sheep primordial follicles cultured in vitro.
Rapid Isocratic Liquid Chromatographic Separation and Quantification of Tryptophan and Six kynurenine Metabolites in Biological Samples with Ultraviolet and Fluorimetric Detection
Authors: Badawy Abdulla A-B , Morgan Christopher J
Published: December 2010

A simple, rapid isocratic liquid chromatographic procedure with ultraviolet and fluorimetric detection is described for the separation and quantification of L-tryptophan (Trp) and six of its kynurenine metabolites (kynurenine, 3-hydroxykynurenine, and 3-hydroxyanthranilic, kynurenic, xanthurenic and anthranilic acids). Using the Perkin Elmer LC 200 system, a reverse phase Synergi 4 μ fusion-RP80 A column (250 × 4.6 mm) (Phenomenex), and a mobile phase of 10 mM sodium dihydrogen phosphate: methanol (73:27, by vol) at pH 2.8 and a flow rate of 1.0–1.2 ml/min at 37 °C, a run took ~13 min. The run took <7 min at 40 °C and a 1.4 ml/min flow rate. Limits of detection of all 7 analytes were 5–72 nM and their recoveries from human plasma and rat serum and liver varied between 62% and 111%. This simple method is suitable for high throughput work and can be further developed to include quinolinic acid and other Trp metabolites.
Concomitant Chemoradiation in Locally Advanced Laryngeal Cancer
Authors: Jamshed Arif , Hussain Raza , Jamshed Sarah , Syed Aamir Ali , Loya Asif , Shah Mazhar Ali , Majeed Uzma , Hameed Shahid
Published: December 2010

Introduction

Despite the acceptance of concomitant chemoradiation (CRT) as an alternative to total laryngectomy (TL) in locally advanced laryngeal cancer (LALC), laryngeal preservation is sparingly recommended in developing countries. We report on prognostic factors and survival in T3/T4 laryngeal cancer treated with concomitant CRT at Shaukat Khanum Memorial Cancer Hospital and Research Center (SKMCH and RC) to provide comparison with other geographic locations.

Material and Methods

During the period November 2003-April 2009, 101 patients with biopsy proven untreated LALC underwent concurrent CRT treatment at SKMCH and RC. According to AJCC staging system (6th edition) 41 had T3 and 60 patients had T4 disease. Radiation dose to the larynx was 70 Gy in 35 fractions with concomitant cisplatin. Induction chemotherapy was given to 42 patients. Thirty-one patients required tracheotomy either before or during concomitant CRT.

Results

Actuarial overall survival and laryngectomy free survival (LFS) for the whole group at 5 years were 54% (95% CI; 48-60) and 47% (95% CI; 42-52) respectively. Median LFS was 4.17 years. On univariate analysis patients with T4 tumors (p = 0.04), positive neck nodal disease (p = 0.02), supraglottic site (p = 0.02) and tracheotomy (0.009) had a significantly inferior LFS. Multivariate analysis showed tracheotomy to be the only factor significantly (p = 0.03) related to a higher risk of failure for LFS.

Conclusion

Survival rates for LALC treated with concomitant CRT in our institution are acceptable. Our study supports the use of TL in patients with compromised airways that require tracheotomy as outcome with concomitant CRT is poor.
Cancrum Oris-associated with Acute Myeloid Leukemia: A Forgotten Disease
Authors: Krishnamurthy Arvind , Sundersingh Shirley , Srinivas Satish , Vaidhyanathan Anita , LNU Krishnarathinam
Published: December 2010

Cancrum oris is an orofacial gangrene, which during its fulminating course causes, progressive and mutilating destruction of the infected tissues with a consortium of microorganisms. This condition is considered to represent the “face of poverty” because factors connected with poverty, such as chronic malnutrition, poor oral hygiene and sanitation, faecal contamination, and exposure to viral and bacterial infections in an immunosupressed host contribute to disease progression. This condition is seen almost exclusively among the young children and carries a high mortality rate.

We present a case of cancrum oris in a 45 years old lady being treated for acute myeloid leukemia with chemotherapy, who in addition to a polymicrobial bacterial infection had superinfection with Mucormycosis.
EFFECTS OF INVESTIGATIVE LABORATORY INSTRUCTION ON CONTENT KNOWLEDGE AND SCIENCE PROCESS SKILL ACHIEVEMENT ACROSS LEARNING STYLES
Authors: Myers Brian E. , Dyer James E.
Published: December 2010

The purpose of this study was to determine the effect of investigative laboratory integration on student content knowledge and science process skill achievement across learning styles. Treatment groups utilized one of three levels of treatment: subject matter approach without laboratory experimentation, subject matter approach with prescriptive laboratory experimentation, and subject matter approach with investigative laboratory experimentation. A nonequivalent control group quasi-experimental design was used. A purposively selected sample based upon the ability of the teacher to effectively deliver the treatments was selected from the population of students enrolled in an introductory agriscience course. Using regression analyses it was determined that learning style, teaching method, ethnicity, content knowledge pretest scores, and science process skill pretest scores accounted for 33% of the variance in content knowledge gain score. Learning style, gender, teaching method, science process skill pretest scores, and content knowledge pretest scores accounted for 36% of the variance in science process skill gain score. Students taught using the subject matter approach or the investigative laboratory approach were reported as having higher content knowledge and science process skill gain scores than students taught using the prescriptive laboratory approach.
BEGINNING AND MENTOR AGRICULTURE TEACHERS’ PERCEPTIONS OF PSYCHOSOCIAL ASSISTANCE, SIMILARITIES, AND SATISFACTION
Authors: Burris Scott , Kitchel Tracy , Greiman Bradley C. , Torres Robert M.
Published: December 2010

The purpose of the study was to describe the extent to which a formal mentoring relationship met psychosocial needs of beginning agriculture teachers and to describe the extent of satisfaction with the dyad relationship. The accepting sample consisted of Missouri agriculture teachers (n = 40) in their first year of teaching during the 2003-2004 school year, and their formal mentors (n = 40) provided by school districts. Data were collected using the Mentoring Relationship Questionnaire (MRQ) developed by Greiman (2002). This instrument consisted of both a beginning teacher version and mentor version. From the findings of the study it was concluded that formal mentors provide psychosocial assistance to beginning agriculture teachers. Psychosocial assistance was intended to enhance a sense of competence, identity, and effectiveness in beginning teachers and consisted of support encompassing the functions of acceptance, counseling, friendship, role modeling, and social. It was found that beginning agriculture teachers and formal mentors who perceive they are similar to their dyad partner are more likely to have a satisfying mentoring experience. Dyad partners who recognize that they have similar values, attitudes, working styles, and teaching philosophies are more likely to have a positive mentoring experience, successful relationship, and satisfactory interaction.
IMPACT OF AN URBAN SERVICE LEARNING EXPERIENCE ON AGRICULTURAL EDUCATION STUDENTS
Authors: Webster Nicole , Hoover Tracy
Published: December 2010

As society becomes more diverse, it is critical that educators provide multiple levels and types of experiences for our students to engage and interact in a multicultural environment. Due to institutional, geographic, and/or departmental demographics, many collegiate students can complete their baccalaureate degree program with limited interaction with individuals from different cultures or ethnic groups. This study utilized a service learning activity as a bridge between a minority-based collegiate organization and an adolescent leadership development class. Participants provided input and reflection on their participation in this event. Four themes: fear of the unknown, moving out of your comfort zone, group activity, and personal impact, emerged from this study that will be used to shape and direct future multicultural service learning activities. Findings support the use of service learning as a positive vehicle to expose students to individuals from different cultures and as a model for future multicultural learning activities with youth based organizations.
On the freshening of the northwestern Weddell Sea continental shelf
Authors: Hellmer H. H. , Huhn O. , Gomis D. , Timmermann R.
Published: December 2010

Abstract. We analysed hydrographic data from the northwestern Weddell Sea continental shelf of three austral winters (1989, 1997 and 2006) and two summers following the last winter cruise. During summer a thermal front exists at ~64° S separating cold southern waters from warm northern waters that have similar characteristics as the deep waters of the central basin of the Bransfield Strait. In winter, the whole continental shelf exhibits southern characteristics with high Neon (Ne) concentrations, indicating a significant input of glacial melt water. The comparison of the winter data at the tip of the Antarctic Peninsula, spanning a period of 17 years, shows a salinity decrease of 0.09 for the whole water column. We interpret this freshening as a reduction in salt input to the water masses being advected northward on the western Weddell Sea continental shelf. Possible causes for the reduced winter salinification are a southward retreat of the summer sea ice edge together with more precipitation in this sector. However, the latter might have happened in conjunction with an increase in ice shelf mass loss, counteracting an enhanced salt input due to sea ice formation in coastal areas formerly occupied by Larsen A and B ice shelves.
Ice-stream response to ocean tides and the form of the basal sliding law
Authors: Gudmundsson G. H.
Published: December 2010

Abstract. The response of ice streams to ocean tides is investigated. Numerical modelling experiments are conduced using a two-dimensional flow-line model of coupled ice-stream and ice-shelf flow. The model includes all components of the equilibrium equations, and uses a non-linear viscoelastic constitutive equation for ice. Basal sliding is simulated with a Weertman type sliding law where basal sliding is proportional to some power of the basal shear stress. The response of ice-streams to tidal forcing is found to be profoundly affected by mechanical conditions at the bed. For a non-linear sliding law, a non-linear interaction between the two main semi-diurnal tidal constituents (M2 and S2) can give rise to a significant perturbation in ice-stream flow at the lunisolar synodic fortnightly (MSf) tidal period of 14.76 days. For a linear sliding law, in contrast, no such modulation in flow at the MSf frequency is found. For vertical ocean tides of the type observed on Filchner-Ronne Ice Shelf (FRIS), the amplitude of the horizontal modulation in ice-stream flow at the MSf frequency resulting from a non-linear interaction between the S2 and M2 tidal constitutes can be larger than the direct response at the S2 and the M2 frequencies. In comparison the non-linear interaction between K1 and O1 tidal components is weak. As a consequence, modelled ice-stream response to mixed oceanic tides of the type found on FRIS is stronger at the MSf period of 14.76 days than at both the semi-diurnal and diurnal frequencies, while at the same time almost absent at the similar Mf period of 13.66 days. The model results compare favourably with measurements of tidally induced flow variations on Rutford Ice Stream (RIS), West Antarctica. On RIS a strong tidal response is found at the MSf frequency with a smaller response at the semi-diurnal and diurnal frequencies, and almost no response at the Mf frequency. A non-linear viscous sliding law with a moderately large exponent (m ≈ 3) appears to have the potential to fully explain these observations.
Contratos con los dawanka y procesos productivos entre los miskitos de las comunidades costeras de la RAAS
Authors: Jamieson Mark
Published: December 2010

Este artículo examina el rol de los 'espíritus dueños' o dawanka quienes para los miskitos controlan la disponibilidad de peces y animales de caza, al igual que el acceso a otros recursos. Mientras que la literatura existente sobre las relaciones entre seres similares y otros pueblos amerindios tiende a demostrar una reciprocidad balanceada o generalizada que enfatiza la reproducción social, las relaciones entre los dawanka y los miskitos de Kakabila son con frecuencia destructivas y de explotación mutua. Este artículo examina la historia socio-económica de la región, las concepciones cambiantes de la noción de persona y materiales recogidos por medio de trabajo de campo, concluyendo que las percepciones actuales de los dawanka y otros seres ‘míticos’ frecuentemente representan un miedo de las formas de cambio motivadas por razones egoístas e individuales que muchos consideran han venido a reemplazar las formas de cambio que son socialmente reproductivas. DOI: 10.5377/wani.v56i0.222Wani No.56 2007 pp.15-24Daniwan atwa kidi karak kantrak yamnin dawak pan minik dahwi yaknin warkni yamnin yulni wayah balna alas lani kat yalahnin sauni atlantik kus wadahni kau tawan balna bang kidi karak. Adika ulna yakat laihwi tatalwi "Pirit palni kidika" awaskat daniwan atwa kidika, wayah balna kukulwi adika dini balna yaklauwi waspa dini balna dawak asangpas dini balna bitik yakat basmumunwi atwi, kaput bik diminit rits dini balna uk kau bik kapat, kaunah uhulna balna as as yakat yuyulwi adika dini balna yulni dawak amerika indianni pah ni balna karak yulni, witingna yuyulwi di bitik kdika pitni kat bangki dawak muih mayangna balna mahni palni sahwi kaiwa sak kidika bik kapat ki atwi, dawak dawanka atwa kidika kakabila wayahni balna karak ampat yalalahwi bang kidika kuduh puyuni bani kau di dutni yayamwi dawak biri biri dau kakalwi uiwi. Uhulna adika laihwi tatalwi ma sauki sahwi yakna nuhni pas yakat ais pitni baraknin lani warkni balna bang kidika, muih pani kat saktada talwa sak kat ampat di balna sat uk kalwi kiwa kidika, dawak pah balna kau uiwi wark yayamna muihni balna ais atwa kidika. Yamni tadi mumunwi tatalna usnit yakat aput atwi, daniwan atwa kidi yulni dawak diauh balna sat uk yulni bik. Puyuni bani yakat yamadangni kapat bik mayawi, mayang alas di balna kidika sins yamdi mawa kidika yulni, ma kulnik dutni yulni bik awaspa awaskat diminit uba anda yulni bik awaspa, muih balna as as kat kukulwi di wisamni kalahwi kaihwa kidika di umani balna panina kau kawi atwi, dawak ma tawanki balna kalalawak barakwi atwi.
Los acuerdos de Esquipulas y los derechos del pueblo costeño
Authors: Campbell Francisco
Published: December 2010

En este artículo, su autor afirma que, a pesar de que los acuerdos de paz y democracia de Esquipulas I y II impulsaron la autonomía de la Costa, sin embargo, esa voluntad política no se hizo extensiva a otros aspectos contemplados, entre éstos, la efectiva reintegración de los municipios de El Rama, Nueva Guinea, Muelle de los Bueyes y el Ayote a la Región Autónoma del Atlántico Sur, y Mulukukú y Waslala a la RAAN. Así como también la lucha contra la pobreza, la desigualdad, la exclusión de pueblos indígenas y pueblos afrodescendientes, y otros graves problemas sociales y económicos que fueron las verdaderas causas y trasfondo de los conflictos armados que por tantos años habían enlutado a los pueblos centroamericanos, entre ellos, los pueblos indígenas de la Costa. DOI: 10.5377/wani.v56i0.225Wani No.56 2007 pp.61-67Kus tawanni ramhni balna dawak Esquipulas kau la balna ahana kidika. Adika uhulna akat, ulna daniwan yaklauwi yulwi, Esquipulas I dawak II kau, la balna uhulwi yayakna pas yakat uhulna dai war dis pri lani kat bang atnin yulni dawak pri lani kat ma ramhki balna yulna atnin kaput bik kus kau alas lani kat yalahnin lani balna yulni bik uhulna dai, kaunah adika dini balna bitik kidika kapat laihwi yayamwas dadana, as as yuldi yakdarang kat laih, sauni sahwi yakna balna El Rama, Nueva Guinea, Muelle de los Bueyes, dawak Ayote atwa balna kidika, ma sauki sahwi yakna nuhni Atlantik Kus Wadah saitni yakat duwi uiwi pakna atnin dai, dawak Mulukuku, Waslala karak laih, ma sauki sahwi yakna nuhni Atlantik Kus tingpal saitni yakat duwi uiwi pakna atnin dai. Kaput bik muih miniknakunni palni bang kidi yakat bik kalpararaswaski, bu as as kat uba yamni bangki dawak baisa mahni kau kidika laih dutni palni bangki, muih sasani balna dawak indian balna kidika witingna pasnina yakat awi duduwaski alas dadawakat bangki, kaput bik, witingna ampat bang kidi tranibil dawak lalah walwi yaknin tranibil balna bitik yulni kuduh biri biri arakbus karak kal ihiwi uina dai kurih mahni kau dawak Centroamerica bitik pas yakat muih mahni palni dadauna dai, kaput adika pas yakan bangki kus indianni tawanni balna bik.
Poemas inéditos de Alí Aláh
Authors: Jo Carlos Castro
Published: December 2010

Alí Aláh era el seudónimo de Santiago Navas, quien nació en Bluefields en 1955 y murió en Costa Rica en 1978. Junto con Carlos Rigby conforma el dúo con el cual arranca la poesía contemporánea del Caribe nicaragüense. En este número de Wani presentamos poemas perdidos y encontrado del Poeta, con la carta de remisión de dichos poemas que gentilmente nos enviara desde Norteamérica el poeta costeño Gustavo Castro Jo. DOI: 10.5377/wani.v57i0.220Wani No.57 2008 pp.79-81Alí Aláh lukanka nani (Poemas) ulbanba sakuna kau uplara mahrikras ba. Alí Aláh wi bangwi kan sakuna witing nina paliba lika Santiago Navas kan, witing Blupil tasbaia ra aisuban mani 1955 ra, witing pruan Costa Rica ra mani 1978 ra. Witing Carlos Rigby wal aikuki prawi lukanka nani(poemas) ulbi bangwan Nikarawa Karibi kuska ba dukiara. Naha wani numbika nara yawan ulbi sakisa lukanka nani(poemas) tiwan kanba pliki saki muni, naha na kus wina poeta kum tetsra iwisa nina ba lika Gustavo Castro Jo wisa, witing bui yawanra wan blikan ulbi sakbia wisi.
Aligning Short Sequencing Reads with Bowtie
Authors: Langmead Ben
Published: December 2010

This unit shows how to use the Bowtie package to align short sequencing reads, such as those output by second‐generation sequencing instruments. It also includes protocols for building a genome index and calling consensus sequences from Bowtie alignments using SAMtools. Curr. Protoc. Bioinform. 32:11.7.1‐11.7.14. © 2010 by John Wiley & Sons, Inc.
The components of an electrochemical cell
Authors: Hamnett A.
Published: December 2010

Electrochemical cells are formed when two electronically conductingelectrodesare placed in an ionically conducting medium, theelectrolyte. When current is passed through the cell, electrochemicalreactionstake place at each electrode, leading to nett chemical conversion of one or more constituents of the cell into new materials. This chapter reviews the nature of the chemical reactions in simple cells, distinguishes between electrolysis and galvanic cell operation, describes the structure and dynamical behavior of the electrolyte, and reviews the properties of some special electrolytes of relevance to fuel cells: ionically conducting membranes, solid ionic conductors and molten salts.
History of high temperature fuel cell development
Authors: Yokokawa H. , Sakai N.
Published: December 2010

The historical overview of high temperature fuel cells, namely, the molten carbonate fuel cell (MCFC) and the solid oxide fuel cell (SOFC), is attempted from the viewpoint of materials development and conversion efficiency. The similarity in materials issues between MCFCs and SOFCs is described with emphasis on the importance of stability properties and mass transfer driven from the gradients of thermodynamic quantities, such as oxygen potential, electrical potential and temperature. The development of MCFCs is described to see how the disadvantages of using molten carbonates can be overcome without losing the advantages of using a liquid electrolyte. Corrosion and shorting due to cathode dissolution limit the life and cell performance. To improve these disadvantages, optimization will be required by full understanding of the interactions of materials with molten carbonates. The development of SOFCs is discussed from the viewpoint of overcoming the mechanical weaknesses caused by the volume changes associated with thermal cycles or atmospheric changes. This weak point makes it necessary to develop cell materials, a processing technique and stack design, simultaneously. The sealless tubular stacks and the planar ones with oxide interconnects are examples of success in establishing these technologies. Against the earlier expectation that SOFCs would suffer from poor material selection and lower efficiency, these SOFC systems have demonstrated that excellent long‐term stability has been achieved at high conversion efficiency without degradation. The second generation SOFC stacks with metal interconnects exhibit similar features to the MCFC stacks development, although the corrosion rate is less severe.
Solid oxide fuel cells (
SOFC
)
Authors: Holtappels P. , Stimming U.
Published: December 2010

Solid oxide fuel cells are fuel cells that operate in a temperature region between 650 °C and 1000 °C by using an oxygen ion conductor as the electrolyte. The ionic transported species are oxygen ions that allow the use of both hydrogen and carbon monoxide as well as directly applied methane as fuels while the oxidant is oxygen provided by air. The state‐of‐the art SOFC consists of an yttria‐stabilized zirconia (YSZ) as the electrolyte, a ceramic metallic composite, a Ni‐YSZ cermet as the fuel electrode and a ceramic composite of strontium doped lanthanum manganite and YSZ as the air electrode. The SOFC is, therefore, an all‐solid state system for which different designs may apply.

Both tubular and planar concepts of SOFC cells and stacks have been developed since the 1960s. The best developed SOFC system is the tubular cell design from Westinghouse (now Siemens Westinghouse Power Corporation), operating at temperatures around 1000 °C. Planar cell designs which allow operating temperatures between 650 °C and 850 °C by using an anode supported electrolyte are under development. The two different concepts, the tubular and the planar design are described in detail and the impact of the supporting component upon important aspects as operating conditions, power density, sealing and contacting are addressed.

SOFC systems have mainly been considered for stationary generation of electricity in combined cycles and co‐generation plants operating on natural gas or oil. New applications are opened in the area of remote power supply in residential but also automotive applications. Principles of systems considered for each application are described in the last section.
Energy storage via electrolysis/fuel cells
Authors: Divisek J. , Emonts B.
Published: December 2010

The application of renewable energy sources requires buffer technology between energy generation and consumption. Energy must be converted into a storable energy carrier such as hydrogen to ensure long‐term supply to the energy consumer. The components under consideration for the conversion processes and for storage are water electrolyzers, fuel cells and gas storage systems.

There are currently two competing methods in water electrolysis: alkaline and polymer membrane electrolysis. Alkaline electrolysis is an established technique operated on an industrial scale. Polymer membrane electrolysis makes use of a solid electrolyte with good conductivity for hydrogen ions and sufficient resistance to oxygen as the separator between the anode and cathode compartment. An interesting alternative from the systems engineering aspect is the bifunctional cell. Equipped with a polymer electrolyte membrane (PEM), the cell can be operated in either mode: as an electrolyzer or a fuel cell.

In fuel cells, the stored hydrogen can be directly converted into electrical energy with oxygen or atmospheric oxygen. Due to the process engineering requirements such as frequent startup and shutdown, as well as the use of hydrogen as the fuel gas, fuel cell types with low operating temperatures are especially suitable for this application, e.g., the alkaline fuel cell (AFC) and the polymer electrolyte fuel cell (PEFC).

The most economical form of gas storage is in tanks at high pressure. Suitable process components are mechanical, electrochemical and thermal compressors. The energetically most favorable process is the compression of liquid water with subsequent decomposition in a high‐pressure electrolyzer. The only hydrogen compression technique that does not need electrical energy is thermal hydrogen compression with metal hydrides.
Outer sphere reactions
Authors: Sánchez C. , Leiva E.
Published: December 2010

A brief introduction to the theory of outer sphere reactions is given.
Noramlization of porous active surfaces
Authors: Nart F. C. , Vielstich W.
Published: December 2010

Surface area normalization of different electrocatalytic materials for fuel cell applications is of fundamental importance for the comparison of different electrode materials. In this chapter we discuss the methodology for surface area normalization using adsorbed probe molecules. Specifically the methodology using adsorption–desorption of hydrogen and carbon monoxide for normalization of active surface areas is discussed. The method entails the determination of the amount of the probe molecule adsorbed on the surface using different methods. Cyclic voltammetry can be used for both hydrogen and CO. In situ infrared spectroscopy and on line mass spectrometry can be used in addition for CO. The surface coverage of hydrogen and CO is discussed for different single crystal electrode surfaces in order to support the use of these methods.
NewCO‐tolerant catalyst concepts
Authors: Watanabe M.
Published: December 2010

Electrocatalytic activity for H2oxidation in the presence of 100 ppm CO has been investigated on a series of binary Pt alloy electrocatalysts with nonprecious metals of various compositions, prepared easily by the sputtering method. Regardless of the composition, Pt/Fe, Pt/Ni, Pt/Co and Pt/Mo alloys have been found to exhibit excellent CO tolerance at H2oxidation similar to Pt/Ru alloy. At these CO tolerant electrodes, the equilibrium coverage of CO was suppressed to values of less than ca. 0.6. Based on X‐ray photoelectron spectroscopy, electrochemical quartz crystal microbalance and scanning tunneling microscopy data, it was found that the surfaces of all nonprecious metal alloys are composed of a thin Pt layer with an electronic structure different from that of pure Pt, indicating a modification of the electronic structure by the underlying alloys. It was found that all such CO tolerant alloys exhibit a positive chemical shift in the core‐level 4f or 4 d orbitals of Pt and vice versa. Such a modification, indicating 5 d vacancy, can be maintained until the thickness grows up to ca 2 nm, then decreases linearly with the increase of thickness and finally coincides with that of bulky Pt beyond ca. 4 nm. The lowered CO coverage, particularly of multi‐bonding, was explained as the result of a lowered 5 d‐electron donation from the Pt band to 2π orbital of CO. A weakening of bond strength between the Pt skin layer and CO was also indicated by in situ Fourier transform infrared spectroscopy, suggesting that H2oxidation sites are not blocked by CO due to its enhanced mobility. Thus, the mechanism of CO tolerance described above at the Pt skin on alloy surfaces is proposed as “detoxification mechanism”. The importance of the examination on the stability as well as the activity of the alloy combinations in the form highly‐dispersed on carbon‐black supports is pronounced from the viewpoint of the practical application to polymer electrolyte fuel cells.
Reaction mechanisms of the
O
2
reduction/evolution reaction
Authors: Gattrell M. , MacDougall B.
Published: December 2010

This chapter attempts to provide an overview of the understanding that has been developed on the mechanisms of reduction and evolution of oxygen. This is discussed mostly in light of oxygen reduction at platinum under close to ambient conditions, though oxygen evolution and various other electrode materials are also mentioned. A general description of this progress in understanding is provided; using results from basic electrochemical polarization and reaction order measurements, rotating ring disk electrode studies, isotopic and adsorption measurements, and insights from volcano plots. The reactions of oxygen are true electrocatalytic reactions (i.e., involving surface adsorbed intermediates) and so are sensitive to the local environment at the electrode surface reaction site. The electrode material, the crystal face, oxide species, and adsorbed electrolyte species therefore affect the reaction. Research to optimize the reaction conditions using alloys of platinum is also briefly discussed.
Oxygen reduction reaction on smooth single crystal electrodes
Authors: Ross P. N.
Published: December 2010

New in‐situ techniques for structure determination at the electrochemical interface have made it possible to use single crystal electrodes in kinetic studies in a definitive way. Use of techniques like surface X‐ray scattering (SXS) and/or scanning tunneling microscopy (STM) under reaction conditions assures that the single crystal surface being studied has a stable and known atomic arrangement. Specifically, this capability has made it possible to determine definitively the structure sensitivity of the oxygen reduction reaction on Pt and Au surfaces. For Pt in sulfuric and phosphoric acid electrolytes, the structure sensitivity is dominated by the inhibiting effects of anion adsorption, which is strongly structure sensitive. In nonadsorbing acids like perchlorate or triflate, the structure sensitivity is weak, probably due to the single‐site nature of the rate‐determining step, i.e., electron transfer to form adsorbed superoxide radical anion. Thus, a particle size effect is not expected for supported Pt catalyst in a PEM fuel cell cathode if the geometric change in particle shape with size is the only factor contributing, i.e., absent electronic effects like quantum confinement. For Au in alkaline electrolyte, oxygen reduction is strongly structure sensitive, with the (100) surface the only Au surface with direct 4e
−
oxidation at potentials near 0.9 V. There is no explanation available for the unique catalytic activity of Au(100) for the ORR in alkaline electrolyte. In acid electrolyte, the ORR polarization curves on Au surfaces are shifted negatively (on a RHE scale) by hundreds of mV, and the reaction becomes structure insensitive. The large effect of pH on the overpotential for ORR on Au is due to the absence of chemisorption of either O
2
or O
2
−
. The rate‐determining step on Au is inner sphere electron transfer to O
2
from O
2
−
, and this reaction step is independent of pH, i.e., the reaction occurs at a fixed potential on a SCE scale, so the overpotential (on an RHE scale) changes with pH.
Fundamental kinetics/transport processes in
MEAs
Authors: Ticianelli E. A. , Gonzalez E. R.
Published: December 2010

The results of fundamental and applied research on the development of dispersed catalysts, gas‐diffusion electrodes and membrane and electrode assemblies (MEAs) for polymer electrolyte fuel cells (PEFCs) are discussed. In the first part, the electrocatalysis of the oxygen reduction reaction on dispersed platinum catalysts used for the preparation of fuel cell electrodes is briefly considered. The issue is analyzed mainly in terms of the size and structure of the catalyst particles. Next, efforts on the development and single cell testing of low catalyst loading gas‐diffusion electrodes for PEFCs are reported in conjunction with the main parameters relating to the properties of the MEAs. The fuel cell polarization behavior is analyzed considering the effects of the structure and composition of the diffusion and catalytic layers of the gas‐diffusion electrode, the cell temperature and gas pressure and the thickness and the water transport through the membrane.
Methanol andCOelectrooxidation
Authors: Iwasita T.
Published: December 2010

Present knowledge of methanol and CO electrooxidation reactions is given in the light of electrochemical, spectroscopic and microscopic data. Strong catalytic effects on CO electrooxidation by nonmetallic adatoms (S, Se, Te) are presented and discussed. For methanol oxidation, several authors have shown, besides CO2, nonnegligible yields of formaldehyde and formic acid, depending among other factors on concentration, potential, electrode roughness and temperature. Infrared spectra assist mechanistic interpretations. Promotion of methanol oxidation by ruthenium presents a maximum effect on alloy materials at room temperature for a surface concentration of Ru between 15% and 45%.
Technical characteristics of
PEM
electrochemical capacitors
Authors: Kosek J. A. , Dweik B. M. , LaConti A. B.
Published: December 2010

Electrochemical capacitors, also known as supercapacitors and ultracapacitors, are capable of very high charge storage. Operating on both pseudocapacitance and double‐layer capacitance, they have demonstrated high capacitance compared to electrolytic and electrostatic capacitors. Electrochemical capacitors have been fabricated from a wide variety of materials, including precious metal oxides and transition metal nitrides as the positive and negative electrode materials, and organic, aqueous, and solid polymer electrolytes. These capacitors have been demonstrated to provide as high as 4 F cm
−2
of active electrode area. Individual cell voltages range from 1 V cell
−1
for aqueous‐based electrolytes, up to 2.5–4 V cell
−1
for organic electrolytes. This publication describes the various types of capacitors, and also compares electrochemical capacitors to batteries. Recent work in the area of electrochemical capacitors is reviewed. The fabrication and operation of all‐solid ionomer or proton‐exchange membrane electrochemical capacitor stacks is targeted for special attention. These devices have been fabricated in a wide range of sizes, ranging from 350‐cell stacks with active areas of 2 cm
2
, to 60‐cell stacks with active areas of 450 cm
2
 cell
−1
. The discharge characteristics and energy storage properties of these devices are described. Specific applications of various capacitor stacks are discussed.