bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of Open Boundary Conditions in a 3D Internal Tidal Model with the Adjoint Method around Hawaii
Authors: Cao Anzhou , Chen Haibo , Zhang Jicai , Lv Xianqing
Published: March 2013

Based on the theory of inverse problem, the optimization of open boundary conditions (OBCs) in a 3D internal tidal model is investigated with the adjoint method. Fourier coefficients ofM2internal tide on four open boundaries, which are regarded as OBCs, are inverted simultaneously. During the optimization, the steepest descent method is used to minimize cost function. The reasonability and feasibility of the model are tested by twin experiments (TEs). In TE1, OBCs on four open boundaries are successfully inverted by using independent point (IP) strategy, suggesting that IP strategy is useful in parameter estimation. Results of TE2 indicate that the model is effective even by assimilating inaccurate “observations.” Based on conclusions of TEs, theM2internal tide around Hawaii is simulated by assimilating T/P data in practical experiment. The simulated cochart shows good agreement with that obtained from the Oregon State University tidal model and T/P observations. Careful inspection shows that the major difference between simulated results and OSU model results is short-scale fluctuations superposed on coamplitude lines, which can be treated as the surface manifestation modulated by the internal tide. The computed surface manifestation along T/P tracks is comparable to the estimation in previous work.
Quality and Timing of Stressors Differentially Impact on Brain Plasticity and Neuroendocrine-Immune Function in Mice
Authors: Capoccia Sara , Berry Alessandra , Bellisario Veronica , Vacirca Davide , Ortona Elena , Alleva Enrico , Cirulli Francesca
Published: March 2013

A growing body of evidence suggests that psychological stress is a major risk factor for psychiatric disorders. The basic mechanisms are still under investigation but involve changes in neuroendocrine-immune interactions, ultimately affecting brain plasticity. In this study we characterized central and peripheral effects of different stressors, applied for different time lengths, in adult male C57BL/6J mice. We compared the effects of repeated (7 versus 21 days) restraint stress (RS) and chronic disruption of social hierarchy (SS) on neuroendocrine (corticosterone) and immune function (cytokines and splenic apoptosis) and on a marker of brain plasticity (brain-derived neurotrophic factor, BDNF ). Neuroendocrine activation did not differ between SS and control subjects; by contrast, the RS group showed a strong neuroendocrine response characterized by a specific time-dependent profile. Immune function and hippocampal BDNF levels were inversely related to hypothalamic-pituitary-adrenal axis activation. These data show a fine modulation of the crosstalk between central and peripheral pathways of adaptation and plasticity and suggest that the length of stress exposure is crucial to determine its final outcome on health or disease.
Investigation of Fe2O3/SiO2 Nanocomposite by FESEM and TEM
Authors: Ang B. C. , Yaacob I. I. , Nurdin Irwan
Published: March 2013

Superparamagnetic maghemite nanoparticles were synthesized using Massart’s procedure. Nanocomposites that consist of the synthesized maghemite nanoparticles and silica were produced by dispersing the as‐synthesized maghemite nanoparticles into the silica xerogel prepared by sol‐gel technique. The system was then heated for 3 days at 140°C. The structure, morphology, and texture of the system were analysed by FESEM and TEM. The result from FESEM showed that the silica gel forms a network structure, which contained numerous pores, with an average pore size of 15 nm. EDX line profile analysis was carried out, and the result indicated that the embedded particles were iron oxide. EELS showed the presence of Fe‐L2 signal, which confirmed the presence of iron oxide particles within the silica matrix. The average diameters were 5.0 nm for as‐synthesized maghemite nanoparticles and 4.4 nm for the embedded maghemite nanoparticles in silica xerogel matrix. The embedded maghemite nanoparticles in nanocomposite also showed a narrower distribution compared to as‐synthesized particles. The magnetization values at 10 kOe applied field, Ms10 kOe, were 9.53 emu/g and 1.79 emu/g for as‐synthesized and embedded nanoparticles, respectively. A reduction in average crystallite size was observed for the dispersed maghemite particles after formation of the nanocomposite indicating a slight dissolution of maghemite nanoparticles in silica gel.
Parameter Optimization via Cuckoo Optimization Algorithm of Fuzzy Controller for Liquid Level Control
Authors: Balochian Saeed , Ebrahimi Eshagh
Published: March 2013

Cuckoo optimization algorithm (COA) is one of the latest evolutionary algorithms. Finding the best optimal point, rapid convergence, and simplicity in determining algorithm parameters are some merits of COA. In this paper, COA is applied to tuning optimal fuzzy parameters for Sugeno-type fuzzy logic controllers (S-FLCs) which are used for liquid level control. A programmable logic controller (PLC) is used with fuzzy controller. For this purpose, a liquid level control set and PLC have been assembled together. MATLAB/Simulink program has been used to achieve the optimal parameters of the membership functions. The results show clearly that the optimized FLC using COA has better performance compared to manually adjustments of the system parameters for different datasets.
Invasive and Noninvasive Multimodal Bedside Monitoring in Subarachnoid Hemorrhage: A Review of Techniques and Available Data
Authors: Arshi Baback , Mack William J. , Emanuel Benjamin
Published: March 2013

Delayed-cerebral ischemia is a major cause of morbidity and mortality in the setting of aneurysmal subarachnoid hemorrhage. Despite extensive research efforts and a breadth of collective clinical experience, accurate diagnosis of vasospasm remains difficult, and effective treatment options are limited. Classically, diagnosis has focused on imaging assessment of the cerebral vasculature. Recently, invasive and noninvasive bedside techniques designed to characterize relevant hemodynamic and metabolic alterations have gained substantial attention. Such modalities include microdialysis, brain tissue oxygenation, jugular bulb oximetry, thermal diffusion cerebral blood flow, and near-infrared spectroscopy. This paper reviews these modalities and examines data pertinent to the diagnosis and management of cerebral vasospasm.
Trends and Impacts of Real and Financial Globalization in the People's Republic of China and India since the 1980s
Authors: Srinivasan TN
Published: April 2013

The dynamic process of integration of national economies has a long history, with two distinct waves: one, from the middle of the 19th century until its interruption with outbreak of the First World War in 1913 till the end of the Second World War in 1945. The second wave is ongoing dating from 1950. Two sub-processes of integration are usually distinguished. The first, called real integration related to flows of goods, services and factors across borders; the second called financial integration related to financial flows of claims on the nominal returns on financial assets. Financial integration has had a checkered history. Private financial flows, particularly debt flows, were evident in the first wave. During the second wave, debt flows, both intergovernmental and private banking lending were dominant during 1950–1980. Only after 1980, private non-debt flows particularly equity flows accelerated.

This paper's primary focus is on the real and financial integration and their impact on trade, growth and poverty in the world's two dominant developing countries in emerging markets, namely the People's Republic of China (PRC) and India. The paper also discusses the reforms of institutional (domestic and multinational) foundations of real and financial integration, particularly the World Trade Organization, the World Bank, the International Monetary Fund, and the Group of 20. The impacts of the 2008–2009 financial crisis on the PRC and India are noted and the need for domestic financial sector reforms in both for them to cope with and respond to future financial crises is pointed out. Attention is drawn to the inadequacy of available analytical tools, in particular the absence of an appropriately integrated model of real and financial sectors to enable a meaningful assessment of the impact of financial shocks on the real sector.
Modes of Collective Action in Village Economies: Evidence from Natural and Artefactual Field Experiments in a Developing Country
Authors: Sawada Yasuyuki , Kasahara Ryuji , Aoyagi Keitaro , Shoji Masahiro , Ueyama Mika
Published: April 2013

In a canonical model of collective action, individual contribution to collective action is negatively correlated with group size. Yet, empirical evidence on the group size effect has been mixed, partly due to heterogeneities in group activities. In this paper, we first construct a simple model of collective action with the free rider problem, altruism, public goods, and positive externalities of social networks. We then empirically test the theoretical implications of the group size effect on individual contribution to four different types of collective action, i.e., monetary or nonmonetary contribution to directly or indirectly productive activities. To achieve this, we collect and employ artefactual field experimental data such as public goods and dictator games conducted in southern Sri Lanka under a natural experimental situation where the majority of farmers were relocated to randomly selected communities based on the government lottery. This unique situation enables us to identify the causal effects of community size on collective action. We find that the levels of collective action can be explained by the social preferences of farmers. We also show evidence of free riding by self-interested households with no landholdings. The pattern of collective action, however, differs significantly by mode of activity—collective action that is directly rather than indirectly related to production is less likely to suffer from the free rider problem. Also, monetary contribution is less likely to cause free riding than nonmonetary labor contribution. Unlike labor contributions, monetary contributions involve collection of fees which can be easily tracked and verified, possibly leading to better enforcement of collective action.
Leading Dragon Phenomenon: New Opportunities for Catch-up in Low-Income Countries
Authors: Chandra Vandana , Lin Justin Yifu , Wang Yan
Published: April 2013

Modern economic development is accompanied by the structural transformation from an agrarian to an industrial economy. Since the 18th century, all countries that industrialized successfully have followed their comparative advantages and leveraged the latecomer advantage, including emerging market economies such as the People's Republic of China (PRC), India, and Indonesia. The current view is that Chinese dominance in manufacturing hinders poor countries from developing similar industries. We argue that rising labor cost is causing the PRC to graduate from labor-intensive to more capital-intensive and technology-intensive industries. This will result in the relocation of low-skill manufacturing jobs to other low-wage countries. This process, which we call the “leading dragon phenomenon,” offers an unprecedented opportunity to low-income countries. Such economies can seize this opportunity by attracting the rising outward foreign direct investment flowing from Brazil, the PRC, India, and Indonesia into the manufacturing sectors. All low-income countries can compete for the jobs spillover from the PRC and other emerging economies, but the winner must implement credible economic development strategies that are consistent with its comparative advantage.
The Political Economy of Policy Reform: Insights from Southeast Asia
Authors: Hill Hal
Published: April 2013

Economists broadly agree on many key economic policy issues, but economics as a discipline has provided much less guidance on why and how economic policy reform occurs and how to develop institutional mechanisms that enable governments to adopt “good” economic policy. Political scientists are adept at identifying coalitions, constituencies, institutions, and interest groups, but they less commonly examine the implications for economic policy. Thus, work at the intersection between economics and politics—of why and how policy reform takes place—remains relatively unexplored territory. This is especially so in developing countries where political processes are more personalistic, institutions often less well established, outcomes more fluid, and the detailed case study literature on economic policy making still in its infancy. This paper provides an analytical survey of economic policy reform in Southeast Asia. It ranges across the major policy U-turns and the incremental reforms, with special reference to macroeconomic management and trade policy. On the basis of several case studies and set against the broader international literature, we advance nine conclusions on the political economy of reform.
A Scalable Memetic Algorithm for Simultaneous Instance and Feature Selection
Authors: García-Pedrajas Nicolás , de Haro-García Aida , Pérez-Rodríguez Javier
Published: April 2013

Instance selection is becoming increasingly relevant due to the huge amount of data that is constantly produced in many fields of research. At the same time, most of the recent pattern recognition problems involve highly complex datasets with a large number of possible explanatory variables. For many reasons, this abundance of variables significantly harms classification or recognition tasks. There are efficiency issues, too, because the speed of many classification algorithms is largely improved when the complexity of the data is reduced. One of the approaches to address problems that have too many features or instances is feature or instance selection, respectively. Although most methods address instance and feature selection separately, both problems are interwoven, and benefits are expected from facing these two tasks jointly. This paper proposes a new memetic algorithm for dealing with many instances and many features simultaneously by performing joint instance and feature selection. The proposed method performs four different local search procedures with the aim of obtaining the most relevant subsets of instances and features to perform an accurate classification. A new fitness function is also proposed that enforces instance selection but avoids putting too much pressure on removing features. We prove experimentally that this fitness function improves the results in terms of testing error. Regarding the scalability of the method, an extension of the stratification approach is developed for simultaneous instance and feature selection. This extension allows the application of the proposed algorithm to large datasets. An extensive comparison using 55 medium to large datasets from the UCI Machine Learning Repository shows the usefulness of our method. Additionally, the method is applied to 30 large problems, with very good results. The accuracy of the method for class-imbalanced problems in a set of 40 datasets is shown. The usefulness of the method is also tested using decision trees and support vector machines as classification methods.
Designation of a lectotype for Deuterodon pedri Eigenmann, 1908 (Characiformes: Characidae)
Authors: DE LUCENA CARLOS ALBERTO SANTOS , DE LUCENA ZILDA MARGARETE SEIXAS
Published: April 2013

Deuterodon pedri was briefly described in 1908 by Carl Eigenmann on the basis of seven specimens of 73–100 mm standard length (SL), all "in very poor condition" according to the author. In the original description, Eigenmann did not mention the location where the specimens were captured, even though the publication presented results of the Thayer expedition to Brazil (Eigenmann 1908: 93).
Nomenclatural changes in the genus Bambusananus Li & Xing, 2011 (Hemiptera: Cicadellidae: Deltocephalinae: Athysanini)
Authors: XING JI-CHUN , CHEN XIANG-SHENG
Published: April 2013

Li & Xing (in Li et al., 2011) established the leafhopper genus Bambusananus with the type species Bambusananus furcatus Li & Xing, 2011 from China. At the same time, three new combinations: Bambusananus binotatus (Li & Dai, 2003), Bambusananus bipunctatus (Li, 1999) and Bambusananus maculipennis (Li & Wang, 1993) were proposed (all species previously placed in the genus Sorhoanus). Subsequently, Yang & Chen (2012) reviewed the genus and described a new species, Bambusananus lii Yang & Chen, 2012. Presently, Bambusananus contains five species.
The millipede order Chordeumatida (Diplopoda) in Kazakhstan, with descriptions of three new species
Authors: MIKHALJOVA ELENA V. , BURKITBAEVA ULZHAN D. , TUF IVAN H. , ULYKPAN KAMAN
Published: April 2013

The order Chordeumatida is represented in Kazakhstan by five species in three genera and three families. All species are recorded in the Altai and Dzhungarskii Alatau Mountains. Three species are described here as new to science: Altajosoma arshaty sp. nov., Altajosoma bukhtarma sp. nov. and Tarbagataya zaisanica sp. nov. The family Diplomaragnidae and the genus Altajosoma Gulička, 1972 are formally new to the fauna of Kazakhstan. Diagnosis of the genus Tarbagataya has been supplemented. All currently known Chordeumatida from Kazakhstan are keyed, including the new species. The distributions of all Kazakhstan chordeumatidan species are mapped.
Two new species of ricinuleids of the genus Pseudocellus (Arachnida: Ricinulei: Ricinoididae) from southern Mexico
Authors: VALDEZ-MONDRAGÓN ALEJANDRO , FRANCKE OSCAR F.
Published: April 2013

Two new species of ricinuleids of the genus Pseudocellus are described from Mexico: Pseudocellus cruzlopezi sp. nov. from Oaxaca, and Pseudocellus monjarazi sp. nov. from Chiapas. Both species are described from adult males and fe-males. The first species is epigean and edaphomorphic, whereas the second is cavernicolous and troglomorphic. The num-ber of known species of the genus Pseudocellus increases to 25, and Mexican species to 16, indicating that Mexico has the highest diversity of ricinuleids in the world. An updated identification key to adult males of the 16 described species found in Mexico and southern USA is provided.
A survey of the internal oral morphology in larvae of the genus Hylodes Fitzinger, 1826 (Amphibia, Anura, Hylodidae)
Authors: WEBER LUIZ NORBERTO , CARAMASCHI ULISSES
Published: April 2013

From the 24 species allocated in the genus Hylodes, 16 have their tadpoles described, which five have information on the oral anatomy. Herein, the internal oral morphology of the tadpoles of H. dactylocinus, H. heyeri, H. aff. lateristrigatus, H. magalhaesi, H. meridionalis, H. phyllodes, H. sazimai, and H. uai is described, along with comparisons among all species in the genus with previously known oral morphology.
The nymph of Anacroneuria payagua Froehlich (Plecoptera: Perlidae) from Brazil
Authors: RIGHI-CAVALLARO KARINA O. , FROEHLICH CLAUDIO G.
Published: April 2013

The unknown nymph of Anacroneuria payagua Froehlich is described based on the association with reared adult females from streams located in Mato Grosso do Sul State, Brazil. Anacroneuria guaikuru Froehlich also occurred in these streams.
The release call as a diagnostic character between cryptic related species Odontophrynus cordobae and O. americanus (Anura: Cycloramphidae)
Authors: GRENAT P. R. , MARTINO L.
Published: April 2013

Diploid Odontophrynus cordobae and tetraploid O. americanus are morphologically cryptic species (Martino and Sinsch 2002). These species occurs in sympatry and syntopy in the SW of the Córdoba province, Argentina (Grenat et al. 2009). At present, individuals of O. cordobae and O. americanus can be only differentiated by mean cytogenetics (Salas 2006; Rosset et al. 2006), which involves the sacrifice of the animal, and erythrometry (Grenat et al. 2009). We propose the release call as a novel character to differentiate these species. Release vocalizations are produced by male anurans as a negative response to male mating attempts. Some studies demonstrated that the release calls of several anuran species differed specifically and that temporal structure of calls could be phylogenetically informative (Brown and Littlejohn 1972; Sullivan and Lamb 1988; Sullivan and Malmos 1994; di Tada et al. 2001). In the genus Odontophrynus, only the release call of O. cordobae has been described (Grenat et al. 2012). The sonograms of O. americanus and O. occidentalis release calls were showed by Barrio (1964), but call measurements were not reported. The aims of present study are: 1) to describe the release call of Odontophrynus americanus; 2) to compare release calls of cryptic species O. cordobae and O. americanus; 3) to evaluate release calls as diagnostic character to distinguish between these species.
Characterization of El-Tih kaolin quality using mineralogical, geochemical and geostatistical analyses
Authors: Masoud A. A. , Christidis G. , Koike K.
Published: March 2013

Detailed multi-scale characterization of the kaolin quality and the controlling depositional environment is crucial for optimal quality upgrading and for prioritizing potential exploitation areas. In the present work, the quality of El-Tih kaolin, Egypt, was investigated using the chemical/mineralogical characteristics as well as the field observations of the clay. Chemical analysis of major oxides was carried out using energy dispersive X-ray fluorescence (EDS-XRF) spectrometry. Mineralogical analyses were carried out using X-ray diffraction (XRD) and scanning electron microscopy coupled with wavelength-dispersive X-ray spectroscopy (SEM-WDS). Spatial heterogeneity of the quality was evaluated applying kriging geostatistical techniques and potential zones were identified.

Results clarified an upward gradual deterioration of the quality via a decrease in the Al2O3content and thickness of the clay layers, and an increase in the TiO2content. According to the kriging maps, areas of high potentiality indices (PI) characterized by high Al2O3and low SiO2content and maximum thickness of the kaolin are located to the west and east, and decrease toward the central part of the study area. The high PI zones are dominated by pseudo-hexagonal platy kaolinite, often forming accordion- and book-like aggregates with subordinate quartz and traces of Fe and Ti oxides, yielding minimal TiO2and Fe2O3contents. These zones of high PI are considered optimal for exploitation. Kaolinite was formed as a result of intensive weathering of rhyolite/granite and basalt in the source area, and subsequent erosion, transportation and deposition of the weathering mantles in a flood environment with marked depositional energy variations. Results allowed comparison with worldwide kaolin occurrences, and suggested the suitability of the studied kaolins for use in paper coating and filling and in higher-grade ceramics, after removal of free Fe- and Ti-oxide impurities.
Structural interpretation of anion exchange in divalent copper hydroxysalt minerals
Authors: Stanimirova TS. , Dencheva S. , Kirov G.
Published: March 2013

Minerals with the general formula Cu4(OH)6A2/nn ± pH2O (A = Cl–, NO3–, SO42–) were synthesized and their behaviour following treatment with chloride, nitrate and sulfate solutions was studied by powder XRD and SEM. Two types of transformation were found: (1) an ion-exchange reaction manifested by preservation of both the precursor's morphology and structural type; (2) a dissolution-crystallization mechanism characterized by changes in the structural type and the morphology.

The results were considered by simultaneous application of the binary presentation of the structures, a bond valence approach and the ion-exchange ability. It was found that the structures of minerals with ion-exchange properties are built from similar layered structural unit of edge-shared and corner-shared Jahn-Teller square frameworks and different interstitial complexes of exchangeable ions, water molecules and cation-water groups. On the basis of their structural features the position of the investigated minerals in mineralogical classifications is also discussed.
Alteration of clay minerals in a sedimentary caprock and its use in geothermal prospecting: an example from Mt. Amiata
Authors: Battaglia S. , Gherardi F. , Gianelli G. , Leoni L. , Lezzerini M.
Published: March 2013

This research work deals with chlorite-vermiculite mixed-layer stability under hydrothermal and metamorphic conditions. We used as a case study a clayey flysch unit cropping out in an active geothermal area near to a Recent volcano (Mt. Amiata) in central Italy. The geothermal gradient is higher than the world average and temperatures over 100°C can occur at less than 1 km depth. The mineralogical data, obtained from X-Ray Power Diffraction (XRPD) analysis of clay samples from the same geologic unit, show that the primary anchimetamorphic mineral assemblage (illite, chlorite, illite-smectite mixed layers) is accompanied by secondary phases, such as chlorite-vermiculite mixed-layers and calcite. Reactive flow modelling was used to outline a realistic water-rock (W/R) interaction process able to generate the new minerals. In the numerical simulation, the pristine shale was made to react with a local thermal spring, at an estimated but realistic carbonate reservoir temperature. The simulation predicts that, at a temperature of 120°C, clinochlore dissolves and vermiculite crystallizes, a good proxy of the chlorite-vermiculite crystallization process. Under low water/rock conditions the proportions of the clay minerals (illite, chlorite, smectite and vermiculite) are comparable with the analytical results. The simulation also shows that temperatures higher than 120°C enhance the vermiculite formation. We conclude that the chlorite-vermiculite mixed-layers formed in the recent past due to the upflow of thermal water which permeated the flysch unit. This result indicates that the alteration of the clayey cap-rocks of geothermal reservoirs is enhanced by the interaction with geothermal fluids, and can be used as a prospecting tool.
Insights into cationic methyl violet 6B dye–kaolinite interactions: kinetic, equilibrium and thermodynamic studies
Authors: Sargin İ. , Ünlü N.
Published: March 2013

In this study, adsorption and adsorption kinetics of methyl violet dye from aqueous solutions onto kaolinite were investigated. The effects of adsorbent dosage, pH, ionic strength, contact time, temperature and initial dye concentration were studied. Kinetic and thermodynamic parameters were determined using experimental data. Adsorption capacity decreased with increasing ionic strength. Changes in the initial pH of the dye solution in a range close to the dye's natural pH (i.e. ∼ pH 5.0) values affected adsorption capacity slightly, indicating that adsorption studies could be carried out at the dye's natural pH. The adsorption process followed the Freundlich-type adsorption isotherms and pseudo-second order type adsorption kinetics. However, an intraparticle diffusion process was found to have effects in adsorption processes. Thermodynamic parameters were calculated from the experimental data and enthalpy of the adsorption, ΔH0, was found to be –6.82 kJ mol–1, indicating physisorption nature of the adsorption. Other thermodynamic parameters, ΔS0 and DG0, were also calculated. Negative values of ΔG0 indicated that the adsorption process for methyl violet on kaolinite is spontaneous.
Iron-bearing smectites: a revised relationship between structural Fe, b cell edge lengths and refractive indices
Authors: Heuser M. , Andrieux P. , Petit S. , Stanjek H.
Published: March 2013

Structural iron in smectites correlates with the cell edge length b and increases the refractive index. The cell edge length b is usually obtained from the position of the (060) reflection, but in this work we show that such b values differ from the values obtained from Rietveld fits because contributions from (hkl) reflections shift the position of the (060) reflection. The correlation between Fe and cell edge length b was significant (r2 > 0.99); the relationship is b [Å] = 8.9977(0.0035) + 0.1117(0.0032) × Fetot. Furthermore, we present for the first time measurements of the refractive index n of Fe-bearing smectites, applying a recently published turbidity method (Weidler & Friedrich, 2007). The refractive index correlates both with structural iron (r2 = 0.64) and with b (r2 = 0.94).
Synthesis, characterization and electrorheological properties of biodegradable chitosan/bentonite composites
Authors: Cabuk M. , Yavuz M. , Unal H. I. , Erol O.
Published: March 2013

Biodegradable chitosan/bentonite composites with three different compositions were synthesized by the intercalation method using cetyltrimethylammonium bromide as the cationic surfactant. The composites were characterized using conductivity, density, particle size measurements, FTIR, TGA, XRD and SEM methods. Colloidal stabilities of the suspensions prepared in silicone oil (SO) were observed to increase with decreasing density. The effects of dispersed particle concentration, shear rate, electric field strength, electric field frequency and temperature on the electrorheological (ER) activities of the suspensions were investigated. The electric field viscosities of the suspensions showed typical shear thinning non-Newtonian viscoelastic behaviour. Yield stresses of the suspensions were observed to change in proportion to the square of applied electric field (E). Further, according to creep and creep-recovery analysis, reversible viscoelastic deformations were observed in the suspensions under E ≠ 0 kV mm–1.
Evidence for the requirement of 14-3-3eta (YWHAH) in meiotic spindle assembly during mouse oocyte maturation
Authors: De Santanu , Kline Douglas
Published: April 2013

Background

The 14-3-3 (YWHA) proteins are central mediators in various cellular signaling pathways regulating development and growth, including cell cycle regulation. We previously reported that all seven mammalian 14-3-3 isoforms are expressed in mouse oocytes and eggs and that, 14-3-3η (YWHAH) accumulates and co-localizes in the region of meiotic spindle in mouse eggs matured in vivo. Therefore, we investigated the role of 14-3-3η in spindle formation during mouse oocyte maturation.

Results

Examination of oocytes matured in vitro demonstrated that 14-3-3η accumulates in both meiosis I and II spindles. To explore if 14-3-3η interacts directly with α-tubulin in meiotic spindles, we performed an in situ proximity ligation assay that can detect intracellular protein-protein interactions at the single molecule level and which allows visualization of the actual interaction sites. This assay revealed a marked interaction between 14-3-3η and α-tubulin at the metaphase II spindle. To demonstrate a functional role for 14-3-3η in oocyte maturation, mouse oocytes were microinjected with a translation-blocking morpholino oligonucleotide against 14-3-3η mRNA to reduce 14-3-3η protein synthesis during oocyte maturation. Meiotic spindles in those cells were examined by immunofluorescence staining of 14-3-3η and α-tubulin along with observation of DNA. In 76% of cells injected with the morpholino, meiotic spindles were found to be deformed or absent and there was reduced or no accumulation of 14-3-3η in the spindle region. Those cells contained clumped chromosomes, with no polar body formation. Immunofluorescence staining of 14-3-3η and α-tubulin in control eggs matured in vitro from uninjected oocytes and oocytes microinjected with the ineffective, inverted form of a morpholino against 14-3-3η, a morpholino against 14-3-3γ, or deionized water showed normal, bipolar spindles.

Conclusions

The results indicate that 14-3-3η is essential for normal meiotic spindle formation during in vitro maturation of mouse oocytes, in part by interacting with α-tubulin, to regulate the assembly of microtubules. These data add to our understanding of the roles of 14-3-3 proteins in mouse oocyte maturation and mammalian reproduction.
Pathophysiology and treatment of focal segmental glomerulosclerosis: the role of animal models
Authors: de Mik Sylvana ML , Hoogduijn Martin J , de Bruin Ron W , Dor Frank JMF
Published: April 2013

Focal segmental glomerulosclerosis (FSGS) is a kidney disease with progressive glomerular scarring and a clinical presentation of nephrotic syndrome. FSGS is a common primary glomerular disorder that causes renal dysfunction which progresses slowly over time to end-stage renal disease. Most cases of FSGS are idiopathic Although kidney transplantation is a potentially curative treatment, 40% of patients have recurrence of FSGS after transplantation. In this review a brief summary of the pathogenesis causing FSGS in humans is given, and a variety of animal models used to study FSGS is discussed. These animal models include the reduction of renal mass by resecting 5/6 of the kidney, reduction of renal mass due to systemic diseases such as hypertension, hyperlipidemia or SLE, drug-induced FSGS using adriamycin, puromycin or streptozotocin, virus-induced FSGS, genetically-induced FSGS such as via Mpv-17 inactivation and α-actinin 4 and podocin knockouts, and a model for circulating permeability factors. In addition, an animal model that spontaneously develops FSGS is discussed. To date, there is no exact understanding of the pathogenesis of idiopathic FSGS, and there is no definite curative treatment. One requirement facilitating FSGS research is an animal model that resembles human FSGS. Most animal models induce secondary forms of FSGS in an acute manner. The ideal animal model for primary FSGS, however, should mimic the human primary form in that it develops spontaneously and has a slow chronic progression. Such models are currently not available. We conclude that there is a need for a better animal model to investigate the pathogenesis and potential treatment options of FSGS.
Neonatal mortality in Sudan: analysis of the Sudan household survey, 2010
Authors: Bashir Amal O , Ibrahim Ghada H , Bashier Igbal A , Adam Ishag
Published: April 2013

Background

Sudan is classified as having insufficient progress in achieving the Millennium Development Goal (MDG-4), where the levels of child and infant mortality are among the highest in the region and the world. This study investigated factors associated with neonatal mortality in Sudan. Neonatal death is defined as death within the first 28 days of life.

Methods

This study analysed data from the Sudan Household Health Survey 2nd round, which was carried out in 2010. Total of 6,198 live-born infants delivered within the two years preceding the survey were included as the study population. Multivariate logistic regression was used to model neonatal mortality as a function of maternal health parameters, socioeconomic indicators and the sex of the child.

Results

There were 189 neonatal deaths out of 6,198 live births (3.0%). In the multiple logistic regression, the factors associated with neonatal mortality were advanced maternal age (≥ 40 years; OR = 2.4; 95% CI: 1.21, 4.78, p = 0.012), poor household wealth index (OR = 1.6; 95% CI: 1.18, 2.47, p = 0.005), male child (OR = 1.8; 95% CI: 1.31, 2.42, p < 0.001), delivery of baby by Caesarean section (OR = 1.6; 95% CI: 1.78, 2.42, p = 0.013) and delivery complications (OR = 1.4; 95% CI: 1.18, 2.15, p = 0.002).

Conclusion

Public health interventions which target neonatal mortality reduction should adopt a risk-factor-based approach to detect pregnancy complications early and once identified, the health system should be strengthened so that these complications can be dealt with adequately.
Benign proliferative breast diseases among female patients at a sub Saharan Africa tertiary hospital: a cross sectional study
Authors: Okoth Christopher , Galukande Moses , Jombwe Josephat , Wamala Dan
Published: April 2013

Background

Non-cancerous diseases of the breast have assumed increasing importance because of the public awareness of breast cancer. These benign diseases are a recognized important risk factor for later breast cancer which can develop in either breast. The risk estimate of these benign breast diseases has not been well established in sub Saharan Africa. Women with benign proliferative or atypical breast lesions have a two- fold risk of developing breast cancer in western populations. The purpose of this study therefore was to determine the prevalence of proliferative disease ( BPBD) with and without atypia among Ugandan Black women.

Methods

A cross-sectional descriptive study conducted at Mulago Hospital Breast Clinic between January 2012 and June 2012; 208 women aged 12 years and above with palpable breast lumps were screened. Fine needle aspiration biopsies were taken for cytological examination.

Results

Of the 208 women with benign breast lumps screened, 195 were recruited in the study. The prevalence of BPBD was 18% (35/195). BPBD with atypia was 5.6% (11/195). The mean age and body mass index (BMI) were 28.4 years and 23.26 kg/m2 respectively. The commonest lesions were fibroadenomas for 57%, (111/195), and fibrocystic change were 21% (40/195). Most BPBD with atypia lesions were in the fibrocystic category.

Conclusions

Benign proliferative breast diseases are common, found mostly among premenopausal women. A significant proportion of BPBD had atypical proliferation. An accurate breast cancer risk estimate study for BPBD is recommended.
Comparative measurement of CNP and NT-proCNP in human blood samples: a methodological evaluation
Authors: Kuehnl Andreas , Pelisek Jaroslav , Bruckmeier Martin , Safi Wajima , Eckstein Hans-Henning
Published: April 2013

Background

C-type natriuretic peptide (CNP) has anti-inflammatory, anti-proliferative, and anti-migratory properties. During the past years, CNP has attained an increasing interest by many research groups, especially in the cardiovascular field. Nevertheless, still no reliable data exist on the difference of CNP concentration between serum and plasma samples. Also, the influence of delayed blood sample proceeding is unknown. The aim of this study was to investigate the difference of CNP and NT-proCNP concentrations between serum and plasma samples. In order to identify potential methodological bias, this study should also validate the stability of CNP and NT-proCNP in full blood samples stored at room temperature.

Findings

Triplets (serum, plasma, full blood) of fasting blood samples from 12 healthy male individuals were collected. Analysis of CNP and NT-proCNP concentration was performed immediately following sampling, and after 30 minutes or 2 hours of storage at room temperature. Mean serum concentrations at baseline were 0.997 ± 0.379 ng/ml for CNP and 58.5 ± 28.3 pg/ml for NT-proCNP. Furthermore, NT-proCNP concentration did not change significantly during the allotted time and did not differ between serum, plasma, and full blood samples. At baseline, concentrations of CNP were significantly different between samples containing either sodium-citrate or EDTA as a clotting inhibitor (1.933 ± 0.699 ng/ml vs. 0.991 ± 0.489 ng/ml, p = 0.001).

Conclusions

CNP and NT-proCNP are stable for at least two hours, even when sample processing is delayed or blood probes are stored at room temperature. NT-proCNP assay demonstrated more consistent and reliable data and should therefore be preferred for usage in clinical applications. Nevertheless, as recommended for ANP and BNP, immunoassays for CNP should also be standardized or harmonized in the future.
Cytogenetic analysis in three Bryconamericus species (Characiformes, Characidae): first description of the 5S rDNA-bearing chromosome pairs in the genus
Authors: Piscor Diovani , Ribacinko-Piscor Daniela Bocagini , Fernandes Carlos Alexandre , Parise-Maltempi Patricia Pasquali
Published: April 2013

Background

Nowadays, the genusBryconamericusis placed in subfamily Stevardiinae within of Characidae, but not shows consistent evidence of monophyletism. The purpose of this work was to study the chromosomes of three species ofBryconamericus, aiming to add cytogenetic knowledge and contribute to the understanding of the chromosomal evolution of this genus.

Results

The chromosomes of three species ofBryconamericuswere analyzed using cytogenetic techniques. The karyotype ofBryconamericus stramineuscontained 6 metacentric (m) + 10 submetacentric (sm) + 16 subtelocentric (st) + 20 acrocentric (a), the fundamental number (FN) of 84, one silver impregnated (Ag-NOR) pair, one pair bearing the 18S ribosomal DNA sites, another pair bearing the 5S rDNA sites, and a few positive C-bands.Bryconamericus turiubahad a karyotype containing 8 m + 10sm + 14st + 20a (FN = 84), one chromosome pair Ag-NOR, two pairs bearing the 18S rDNA sites, two pairs bearing the 5S rDNA sites, and a few C-band regions.Bryconamericuscf.iheringiihad a karyotype containing 10 m + 14sm + 18st + 10a (FN = 94), including one pair with a secondary constriction Ag-NOR positive. In this karyotype the fluorescent in situ hybridization (FISH) showed the 18S and 5S rDNA probe in adjacent position.

Conclusions

The results obtained in this work showed different characteristics in the organization of two multigene families, indicating that distinct evolutionary forces acting on the diversity of rDNA sequences in the genome of threeBryconamericusspecies.
Germ-line DICER1 mutations do not make a major contribution to the etiology of familial testicular germ cell tumours
Authors: Sabbaghian Nelly , Bahubeshi Amin , Shuen Andrew Y , Kanetsky Peter A , Tischkowitz Marc D , Nathanson Katherine L , Foulkes William D
Published: April 2013

Background

The RNase III enzyme DICER1 plays a central role in maturation of microRNAs. Identification of neoplasia-associated germ-line and somatic mutations in DICER1 indicates that mis-expression of miRNAs in cancer may result from defects in their processing. As part of a recent study of DICER1 RNase III domains in 96 testicular germ cell tumors, a single RNase IIIb domain mutation was identified in a seminoma. To further explore the importance of DICER1 mutations in the etiology of testicular germ cell tumors (TGCT), we studied germ-line DNA samples from 43 probands diagnosed with familial TGCT.

Findings

We carried out High Resolution Melting Curve Analysis of DICER1 exons 2–12, 14–19, 21 and 24–27. All questionable melt curves were subjected to confirmatory Sanger sequencing.

Sanger sequencing was used for exons 13, 20, 22 and 23. Intron-exon boundaries were included in all analyses. We identified 12 previously reported single nucleotide polymorphisms and two novel single nucleotide variants. No likely deleterious variants were identified; notably no mutations that were predicted to truncate the protein were identified.

Conclusions

Taken together with previous studies, the findings reported here suggest a very limited role for either germ-line or somatic DICER1 mutations in the etiology of TGCT.
Thyroid hormone-induced cell-cell interactions are required for the development of adult intestinal stem cells
Authors: Hasebe Takashi , Fu Liezhen , Miller Thomas C , Zhang Yu , Shi Yun-Bo , Ishizuya-Oka Atsuko
Published: April 2013

The mammalian intestine has long been used as a model to study organ-specific adult stem cells, which are essential for organ repair and tissue regeneration throughout adult life. The establishment of the intestinal epithelial cell self-renewing system takes place during perinatal development when the villus-crypt axis is established with the adult stem cells localized in the crypt. This developmental period is characterized by high levels of plasma thyroid hormone (T3) and T3 deficiency is known to impair intestinal development. Determining how T3 regulates adult stem cell development in the mammalian intestine can be difficult due to maternal influences. Intestinal remodeling during amphibian metamorphosis resembles perinatal intestinal maturation in mammals and its dependence on T3 is well established. A major advantage of the amphibian model is that it can easily be controlled by altering the availability of T3. The ability to manipulate and examine this relatively rapid and localized formation of adult stem cells has greatly assisted in the elucidation of molecular mechanisms regulating their formation and further revealed evidence that supports conservation in the underlying mechanisms of adult stem cell development in vertebrates. Furthermore, genetic studies inXenopus laevisindicate that T3 actions in both the epithelium and the rest of the intestine, most likely the underlying connective tissue, are required for the formation of adult stem cells. Molecular analyses suggest that cell-cell interactions involving hedgehog and BMP pathways are critical for the establishment of the stem cell niche that is essential for the formation of the adult intestinal stem cells.
Influence of water replacement on Diflubenzuron duration effect in the control of Aedes aegypti in simulated field conditions, in Northeastern Brazil
Authors: Garcia Neto Levindo Jose , De Goes Cavalcanti Luciano Pamplona , Pontes Ricardo Jose Soares , Lima José Wellington Oliveira
Published: April 2013

Introduction: Theoretically, it is possible to control dengue by reducing breeding sites. However in most countries, it has not been possible to obtain sustainable dengue control using only the reduction of potential breeding sites thus use of larvicides continues to be necessary. This paper presents an estimate of the rate of water replacement in residential water containers in the city of Fortaleza, northeast Brazil, and the respective duration of the effect of Diflubenzuron on Aedes aegypti immatures. Methods: Several trials were performed to estimate the duration of the effect of Diflubenzuron in simulated field conditions with replacement daily with 20% by volume of water. Eighteen containers with 20 litres of water treated with Diflubenzuron, and 6 containers with well water were used. The initial concentration of Diflubenzuron in the treated containers was 2.875 x 10-4 grams/litre. Third stages larvae were added to the containers, the first day of experiment. All the containers were inspected daily and dead larvae and pupae were removed and counted. Each trial was terminated when all larvae added to one of the groups (treated or control) had died or pupated. Results: From the 1st to the 19th day, the Diflubenzuron achieved 100% control, adjusting for the emergence of pupae in untreated containers not allowing any larvae to develop into pupae. From the 20th to the 70th day, the control ranged from 97.9% to 36.6%. Conclusions: This study reports a good larvicide effect of Diflubenzuron in the doses used by the Brazilian Programme of Dengue Control.
Can the Ottawa and Pittsburgh rules reduce requests for radiography in patients referred to acute knee clinics?
Authors: Konan S , Zang TT , Tamimi N , Haddad FS
Published: March 2013

Our aim was to study the role of the Ottawa and Pittsburgh rules to reduce the unnecessary use of radiographs following knee injury. We prospectively reviewed 106 patients who were referred to our clinic over a 3-month period. The Ottawa and Pittsburgh rules were applied to individual patients to evaluate the need for radiography. One hundred and one patients (95%) had radiography of their knee. Five patients (5%) had a fracture of their knee and in all cases, the Ottawa and Pittsburgh knee rules were fulfilled. Using the Ottawa rules, 27 radiographs (25%) could have been avoided without missing a fracture. Using the Pittsburgh rules, 32 radiographs (30%) could have been avoided. The Ottawa and Pittsburgh rules have a high sensitivity for the detection of knee fractures. Their use can aid efficient clinical evaluation without adverse clinical outcome and may reduce healthcare costs.