bluuebunny/crossref_metadata_2025 huggingface dataset:
Ocean acidification indirectly alters trophic interaction of heterotrophic bacteria at low nutrient conditions
Authors: Hornick Thomas , Bach Lennart T. , Crawfurd Katharine J. , Spilling Kristian , Achterberg Eric P. , Brussaard Corina P. D. , Riebesell Ulf , Grossart Hans-Peter
Published: March 2016

Abstract. Annually, the oceans absorb about one fourth of the anthropogenically produced atmospheric carbon dioxide (CO2) resulting in a drop in surface water pH, a process termed ocean acidification (OA). Surprisingly little is known about how OA affects physiology as well as food web interactions of heterotrophic bacteria when essential nutrients are limited, since most previous experiments were carried out during productive phases or even after nutrient additions to stimulate algal blooms. Therefore, we conducted an in situ large-volume mesocosm (~55 m3) experiment in the Baltic Sea by simulating different fugacities of CO2 (fCO2) extending from present to future conditions. The study was carried out after the spring-bloom in July–August to maintain low-nutrient conditions throughout the experiment, which resulted in a small-sized phytoplankton community dominated by picophytoplankton. Several positive as well as negative effects on free-living (FL) and particle-associated (PA) bacterial protein production (BPP) and biovolume (BV) could be related to fCO2-induced differences in phytoplankton composition and subsequent the availability of phytoplankton-derived organic matter. However, dynamics of BV and cell-specific BPP (csBPP) of FL heterotrophic bacteria could not be explained exclusively by the availability of phytoplankton-derived organic carbon. The dynamics were also related to enhanced grazing on DNA rich (HDNA) bacterial cells at higher fCO2 as revealed by flow cytometry. Additionally, a decoupling of autotrophic production and heterotrophic consumption during the last third of the experiment resulted in low, but significantly higher accumulation of DOC at enhanced fCO2. Interestingly we could not detect any consistent and direct fCO2-induced effect on BPP, csBPP nor BV of either FL or PA heterotrophic bacteria. In contrast, our results reveal several indirect fCO2-induced effects on BPP and bacterial BV with potential consequences for oceanic carbon cycling, in particular in a low nutrient and high fCO2 future ocean.
Close range photogrammetric methods applied to the study of the fronts of Johnsons and Hurd Glaciers (Livingston Island, Antarctica) from 1957 to 2013
Authors: Rodríguez Ricardo , Aguirre Julián , Díez Andrés , Álvarez Marina , Rodríguez Pedro
Published: March 2016

Abstract. The study of glacier fronts combines different geomatics measurement techniques as the classic survey using total station or theodolite, technical GNSS (Global Navigation Satellite System), using laser-scanner or using photogrammetry (air or ground). The measure by direct methods (classical surveying and GNSS) is useful and fast when accessibility to the glaciers fronts is easy, while it is practically impossible to realize, in the case of glacier fronts that end up in the sea (tide water glaciers). In this paper, a methodology that combines photogrammetric methods and other techniques for lifting the front of the glacier Johnsons, inaccessible is studied. The images obtained from the front, come from a non-metric digital camera; its georeferencing to a global coordinate system is performed by measuring points GNSS support in accessible areas of the glacier front side and applying methods of direct intersection in inaccessible points of the front, taking measurements with theodolite. The result of observations obtained were applied to study the temporal evolution (1957–2014) of the position of the Johnsons glacier front and the position of the Argentina, Las Palmas and Sally Rocks lobes front (Hurd glacier). Link to the data repository: doi:10.1594/PANGAEA.845379
Modelling sediment clasts transport during landscape evolution
Authors: Carretier Sébastien , Martinod Pierre , Reich Martin , Godderis Yves
Published: March 2016

Abstract. Over thousands to millions of years, the landscape evolution is predicted by models based on fluxes of eroded, transported and deposited material. The laws describing these fluxes, corresponding to averages over many years, are difficult to prove with the available data. On the other hand, sediment dynamics are often tackled by studying the distribution of certain grain properties in the field (e.g. heavy metals, detrital zircons, 10Be in gravel, magnetic tracers). There is a gap between landscape evolution models based on fluxes and these field data on individual clasts, which prevent the latter from being used to calibrate the former. Here we propose an algorithm coupling the landscape evolution with mobile clasts. Our landscape evolution model predicts local erosion, deposition and transfer fluxes resulting from hillslope and river processes. Clasts of any size are initially spread in the basement and are detached, moved and deposited according to probabilities using these fluxes. Several river and hillslope laws are studied. Although the resulting mean transport rate of the clasts does not depend on the time step or the model cell size, our approach is limited by the fact that their scattering rate is cell-size-dependent. Nevertheless, both their mean transport rate and the shape of the scattering-time curves fit the predictions. Different erosion–transport laws generate different clast movements. These differences show that studying the tracers in the field may provide a way to establish these laws on the hillslopes and in the rivers. Possible applications include the interpretation of cosmogenic nuclides in individual gravel deposits, provenance analyses, placers, sediment coarsening or fining, the relationship between magnetic tracers in rivers and the river planform, and the tracing of weathered sediment.
MAHLI on Mars: lessons learned operating a geoscience camera on a landed payload robotic arm
Authors: Yingst R. Aileen , Edgett Kenneth S. , Kennedy Megan R. , Krezoski Gillian M. , McBride Marie J. , Minitti Michelle E. , Ravine Michael A. , Williams Rebecca M. E.
Published: March 2016

Abstract. The Mars Hand Lens Imager (MAHLI) is a 2-megapixel, color camera with resolution as high as 13.9 µm/pixel. MAHLI has operated successfully on the martian surface for over 1150 martian days (sols) aboard the Mars Science Laboratory (MSL) rover, Curiosity. During that time MAHLI acquired images to support science and science enabling activities, including rock and outcrop textural analysis; sand characterization to further the understanding of global sand properties and processes; support of other instrument observations; sample extraction site documentation; range-finding for arm and instrument placement; rover hardware and instrument monitoring and safety; terrain assessment; landscape geomorphology; and support of rover robotic arm commissioning. Operation of the instrument has demonstrated that imaging fully illuminated, dust-free targets yields the best results, with complementary information obtained from shadowed images. The LEDs allow satisfactory nighttime imaging but do not improve daytime shadowed imaging. MAHLI's combination of fine-scale, science-driven resolution, RGB color, ability to focus over a large range of distances, and relatively large FOV, have maximized the return of science and science-enabling observations given the MSL mission architecture and constraints.
Numerical framework and performance of the new multiple phase cloud microphysics scheme in RegCM4.5: precipitation, cloud microphysics and cloud radiative effects
Authors: Nogherotto Rita , Tompkins Adrian Mark , Giuliani Graziano , Coppola Erika , Giorgi Filippo
Published: March 2016

Abstract. We implement and evaluate a new parameterization scheme for stratiform cloud microphysics and precipitation within the regional climate model RegCM4. This new parameterization is based on a multiple phase one-moment cloud microphysics scheme built upon the implicit numerical framework recently developed and implemented into the ECMWF operational forecasting model. The parameterization solves 5 prognostic equations for water vapour, cloud liquid water, rain, cloud ice and snow mixing ratios. Compared to the pre-existing scheme, it allows a proper treatment of mixed-phase clouds and a more physically realistic representation of cloud miscrophysics and precipitation. Various fields from a 10-yr-long integration of RegCM4 run in tropical band mode with the new scheme are compared with their counterparts using the previous cloud scheme as well as with satellite observations through the use of the COSP simulator. The new microphysics parameterization yields an improved simulation of cloud fields and in particular it removes the overestimation of upper level clouds characteristics of the previous scheme, increasing the agreement with observations and leading to an amelioration of a long-standing problem in the RegCM system. The vertical cloud profile produced by the new scheme leads to a considerably improvement of the representation of the longwave and shortwave components of the cloud radiative forcing.
Evaluation of an operational ocean model configuration at 1/12° spatial resolution for the Indonesian seas (NEMO2.3/INDO12) – Part 1: Ocean physics
Authors: Tranchant Benoît , Reffray Guillaume , Greiner Eric , Nugroho Dwiyoga , Koch-Larrouy Ariane , Gaspar Philippe
Published: March 2016

Abstract. INDO12 is a 1/12° regional version of the NEMO physical ocean model covering the whole Indonesian EEZ (Exclusive Economic Zone). It has been developed and is now running every week in the framework of the INDESO (Infrastructure Development of Space Oceanography) project implemented by the Indonesian Ministry of Marine Affairs and Fisheries. The initial hydrographic conditions as well as open-boundary conditions are derived from the operational global ocean forecasting system at 1/4° operated by Mercator Océan. Atmospheric forcing fields (3-hourly ECMWF (European Centre for Medium-Range Weather Forecast) analyses) are used to force the regional model. INDO12 is also forced by tidal currents and elevations, and by the inverse barometer effect. The turbulent mixing induced by internal tides is taken into account through a specific parameterisation. In this study we evaluate the model skill through comparisons with various data sets including outputs of the parent model, climatologies, in situ temperature and salinity measurements, and satellite data. The biogeochemical model results assessment is presented in a companion paper (Gutknecht et al., 2015). The simulated and altimeter-derived Eddy Kinetic Energy fields display similar patterns and confirm that tides are a dominant forcing in the area. The volume transport of the Indonesian throughflow (ITF) is in good agreement with the INSTANT estimates while the transport through Luzon Strait is, on average, westward but probably too weak. Compared to satellite data, surface salinity and temperature fields display marked biases in the South China Sea. Significant water mass transformation occurs along the main routes of the ITF and compares well with observations. Vertical mixing is able to modify the South and North Pacific subtropical water-salinity maximum as seen in T–S diagrams. In spite of a few weaknesses, INDO12 proves to be able to provide a very realistic simulation of the ocean circulation and water mass transformation through the Indonesian Archipelago. Work is ongoing to reduce or eliminate the remaining problems in the second INDO12 version.
An improved global zenith tropospheric delay model GZTD2 considering diurnal variations
Authors: Yao YiBin , Hu YuFeng , Yu Chen , Zhang Bao , Guo JianJian
Published: March 2016

Abstract. The zenith tropospheric delay (ZTD) is an important atmospheric parameter in the wide application of GNSS technology in geoscience. Given that the temporal resolution of the current Global Zenith Tropospheric Delay model (GZTD) is only 24 h, an improved model GZTD2 has been developed by taking the diurnal variations into consideration and modifying the model expansion function. The data set used to establish this model is the global ZTD grid data provided by Global Geodetic Observing System (GGOS) Atmosphere spanning from 2002 to 2009. We validated the proposed model with respect to ZTD grid data from GGOS Atmosphere, which was not involved in modeling, as well as International GNSS Service (IGS) tropospheric product. The obtained results of ZTD grid data show that the global average Bias and RMS for GZTD2 model are 0.2 cm and 3.8 cm respectively. The global average Bias is comparable to that of GZTD model, but the global average RMS is improved by 3 mm. The Bias and RMS are far better than EGNOS model and the UNB series models. The testing results from global IGS tropospheric product show the Bias and RMS (−0.3 cm and 3.9 cm) of GZTD2 model are superior to that of GZTD (−0.3 cm and 4.2 cm), suggesting higher accuracy and reliability compared to the EGNOS model, as well as the UNB series models.
Wave extreme characterization using self-organizing maps
Authors: Barbariol Francesco , Falcieri Francesco Marcello , Scotton Carlotta , Benetazzo Alvise , Carniel Sandro , Sclavo Mauro
Published: March 2016

Abstract. The self-organizing map (SOM) technique is considered and extended to assess the extremes of a multivariate sea wave climate at a site. The main purpose is to obtain a more complete representation of the sea states, including the most severe states that otherwise would be missed by a SOM. Indeed, it is commonly recognized, and herein confirmed, that a SOM is a good regressor of a sample if the frequency of events is high (e.g., for low/moderate sea states), while a SOM fails if the frequency is low (e.g., for the most severe sea states). Therefore, we have considered a trivariate wave climate (composed by significant wave height, mean wave period and mean wave direction) collected continuously at the Acqua Alta oceanographic tower (northern Adriatic Sea, Italy) during the period 1979–2008. Three different strategies derived by SOM have been tested in order to capture the most extreme events. The first contemplates a pre-processing of the input data set aimed at reducing redundancies; the second, based on the post-processing of SOM outputs, consists in a two-step SOM where the first step is applied to the original data set, and the second step is applied on the events exceeding a given threshold. A complete graphical representation of the outcomes of a two-step SOM is proposed. Results suggest that the post-processing strategy is more effective than the pre-processing one in order to represent the wave climate extremes. An application of the proposed two-step approach is also provided, showing that a proper representation of the extreme wave climate leads to enhanced quantification of, for instance, the alongshore component of the wave energy flux in shallow water. Finally, the third strategy focuses on the peaks of the storms.
River bulge evolution and dynamics in a non-tidal sea – Daugava River plume in the Gulf of Riga, Baltic Sea
Authors: Soosaar Edith , Maljutenko Ilja , Uiboupin Rivo , Skudra Maris , Raudsepp Urmas
Published: March 2016

Abstract. Satellite remote sensing imagery and numerical modelling were used for the study of river bulge evolution and dynamics in a non-tidal sea, the Gulf of Riga (GoR) in the Baltic Sea. Total suspended matter (TSM) images showed a clearly formed anti-cyclonically rotating river bulge from Daugava River discharge during the studied low wind period. In about 7–8 days the bulge grew up to 20 km in diameter, before being diluted. A high-resolution (horizontal grid step of 125 m) General Estuarine Transport Model (GETM) was used for detailed description of the development of the river plume in the southern GoR over the period when satellite images were acquired. In the model simulation, the bulge growth rate was estimated as rb ∼ t0.5 ± 0.04 (R2 = 0.90). Both the model simulation and the satellite images showed that river water was mainly contained in the bulge and there were numerous intrusions at the outer perimeter of the bulge. We performed numerical sensitivity tests with actual bathymetry and measured river runoff without wind forcing (1) having an initial three-dimensional density distribution, and (2) using initially a homogeneous ambient density field. In the first case, the anti-cyclonic bulge did not develop within the course of the model simulation and the coastal current was kept offshore due to ambient density-driven circulation. In the second case, the river plume developed steadily into an anti-cyclonically recirculating bulge, with rb ∼ t0.28 ± 0.01 (R2 = 0.98), and a coastal current. Additional simulations with constant cross-shore and alongshore winds showed a significant effect of the wind in the evolution of the river bulge, even if the wind speed was moderate (3–4 m s−1). While previous studies conclude that the mid-field bulge region is governed by a balance between centrifugal, Coriolis and pressure gradient terms, our study showed that geostrophic balance is valid for the entire mid-field of the bulge, except during the 1–1.5 rotation period at the beginning of the bulge formation. In addition, while there is discharge into the homogenous GoR in the case of a high inflow Rossby number, the river inflow might split into two jets, with strong mixing zone in-between, in the plume near-field region.
Differences and influencing factors for underground water carbon uptake by karsts in Houzhai Basin, southwest China
Authors: Zhang Junyi , Bian Zihao , Dai Minghong , Wang Lachun , Su Weici
Published: March 2016

Abstract. Karst geological carbon sink is an important part of the global carbon sink, so how to get the accurate carbon sink of karst ecosystem has become the core issue of the research. We used flow and carbon ion concentration data from three stations with different environmental background conditions in the Houzhai basin to analyze the differences in carbon uptake between stations and their impact factors. Results show that carbon sink discharge was mainly controlled by the flow of each site. The rapid increase in flow only has a partial dilution effect on ion concentrations, preliminary analysis considered due to the high speed and stability of chemical carbonate weathering. LUCC type has important effects on the bicarbonate ions concentrations, if runoff is stable, the influence of flow variation on ion concentration will be less than the effects of chemical carbonate weathering in different environmental conditions (comparison of Laoheitan and Liugu station results is 150 %) on bicarbonate ion concentrations. However, if runoff increases significantly, the impact of runoff variation on bicarbonate ions will be greater than the effects of chemical carbonate weathering by different environmental conditions (comparison results of Laoheitan and Maoshuikeng station). This work provides a reference for the calculation of karst geological carbon sink.
Soil indicators to assess the effectiveness of restoration strategies in dryland ecosystems
Authors: Costantini Edoardo A. C. , Branquinho Cristina , Nunes Alice , Schwilch Gudrun , Stavi Ilan , Valdecantos Alejandro , Zucca Claudio
Published: March 2016

Abstract. Soil indicators may be used for assessing both land suitability for restoration and the effectiveness of restoration strategies in restoring ecosystem functioning and services. In this review paper, several soil indicators, which can be used to assess the effectiveness of ecological restoration strategies in dryland ecosystems at different spatial and temporal scales, are discussed. The selected indicators represent the different viewpoints of pedology, ecology, hydrology, and land management. Two overall outcomes stem from the review. (i) The success of restoration projects relies on a proper understanding of their ecology, namely the relationships between soil, plants, hydrology, climate, and land management at different scales, which are particularly complex due to the heterogeneous pattern of ecosystems functioning in drylands. (ii) The selection of the most suitable soil indicators follows a clear identification of the different and sometimes competing ecosystem services that the project is aimed at restoring.
Morphological dynamics of gully systems in the sub-humid Ethiopian Highlands: The Debre Mawi watershed
Authors: Zegeye Assefa , Langendoen Eddy J. , Stoof Cathelijne R. , Tilahun Seifu A. , Dagnew Dessalegn C. , Zimale Fasikaw A. , Guzman Christian D. , Yitaferu Birru , Steenhuis Tammo S.
Published: March 2016

Abstract. Gully expansion in the Ethiopian highlands dissects vital agricultural lands with the eroded materials adversely impacting downstream resources, for example as they accumulate in reservoirs. While gully expansion and rehabilitation have been more extensively researched in the semi-arid region of Ethiopia, few studies have been conducted in the (sub) humid region. For that reason, we assessed the severity of gully erosion and identified gully-forming processes in 13 selected permanent gullies in the sub-humid Debre Mawi watershed, 30 km south of Lake Tana, Ethiopia. In addition, the rate of expansion of the entire drainage network in the watershed was determined using 50 cm resolution aerial imagery flown in 2005 and 2013. More than 0.7 million tons (or 155 t ha−1 yr−1) of soil was lost during this period due to actively expanding gullies. The net gully area in the entire watershed increased more than 4-fold from 4.5 ha in 2005 to 20.4 ha in 2013 (> 3 % of the watershed area), indicating the growing severity of gully erosion and hence land degradation in the watershed. Soil losses were caused by upslope migrating gully heads through a combination of gully head collapse and removal of the failed material by runoff. Collapse of gully banks and retreat of headcuts was most severe in locations where elevated groundwater tables saturated gully head and bank soils, destabilizing the soils by decreasing their shear strength. Elevated groundwater tables were thereby the most important cause of gully expansion. Additional factors that strongly relate to bank collapse were the height of the gully head and the size of the drainage area. Soil physical properties (e.g., texture and bulk density) only had minor effects. Conservation practices that address the most important controlling factors are principally the most effective ways of protecting gully development and expansion. These consist of lowering water table elevation and regrading the gully head and sidewall to reduce the occurrence of gravity-induced mass failures. Planting suitable vegetation on the gully face and around the boundary can also decrease the risk of bank failure by reducing pore-water pressures and reinforcing the soil. Best management practices affecting the runoff contributing catchment may decrease the overland runoff-induced gully head erosion.
Aspectos epidemiológicos das crianças com queimaduras internadas no Pronto Socorro para Queimaduras de Goiânia – Goiás
Authors: Viana Fabiana Pavan , Resende Selma Mendes , Tolêdo Márcia Claudina , Silva Roberta Cordeiro
Published: March 2016

As crianças são as vítimas mais frequentes das queimaduras e estas a segunda causa de morte acidental na infância. O objetivo deste trabalho foi investigar as características epidemiológicas de crianças de 0 a 14 anos, vítimas de queimaduras, internadas no Pronto Socorro para Queimaduras de Goiânia - Goiás. Para isto, dados obtidos no Banco de Dados do hospital e prontuários das crianças internadas no período de 1º de junho de 2005 a 1º de junho de 2007 foram analisados. As crianças foram divididas em dois grupos: Grupo I (0-4 anos) e Grupo II (5-14 anos). Em ambos os grupos o sexo masculino foi predominante e a maioria dos atendimentos ocorreu via convênio do hospital com o Sistema Único de Saúde. O principal local dos acidentes foi na residência. O agente causal mais comum no Grupo I foram os líquidos superaquecidos e no Grupo II, as chamas (p<0,001). Quarenta e dois por cento das crianças tiveram de 10 a 19% da superfície corporal queimada. Sugere-se a inclusão de programas educativos na comunidade, nas Unidades Básicas de Saúde, nas escolas de educação infantil e creches, que auxiliem na conscientização dos cuidadores quanto às formas de prevenção das queimaduras.
Uso de dispositivo automático de medida de pressão arterial em crianças entre 4 e 13 anos
Authors: Reis Roberta Silveira dos , Lamas José Luiz Mendes
Published: March 2016

Estudo realizado para averiguar a confiabilidade de valores obtidos na aferição de pressão arterial em crianças com um aparelho automático de medida de pressão arterial. Tem como objetivos verificar os valores de pressão nas artérias braquial e radial de crianças pelo método auscultatório com o manguito de largura correta e compará-los aos valores obtidos nas mesmas artérias com instrumento automático. A pesquisa foi realizada com crianças atendidas em um hospital universitário do interior do estado de São Paulo. Utilizou-se o monitor digital de pressão arterial de pulso Tech Line WS-501. A amostra, de 100 crianças, compôs-se de crianças cuja circunferência do braço ou punho estava entre 14 e 17 cm, adequadas ao uso do manguito de 6 cm de largura. O aparelho foi utilizado seguindo suas especificações. Os valores da pressão arterial sistólica obtidos com o aparelho automático foram superiores à coluna de mercúrio em 1,38 mmHg, em média. Em relação à pressão arterial diastólica, os valores obtidos com o aparelho de mercúrio foram superiores ao aparelho digital em 1,22 mmHg, em média. Assim, o aparelho Tech Line WS-501 mostrou-se adequado para o uso clínico, desde que a circunferência destes membros esteja de acordo com as especificações do aparelho automático.
Homoenxerto em cirurgia de valvas cardíacas: evidências para a prática da enfermagem perioperatória
Authors: Pelegrino Flávia Martinelli , Torrati Fernanda Gaspar , Sawada Namie Okino , Galvão Cristina Maria
Published: March 2016

O uso clínico de homoenxertos de valvas cardíacas é amplamente utilizado como técnica cirúrgica para várias doenças cardiovasculares. Dentre as atividades realizadas pela enfermagem há o descongelamento de homoenxerto no período intra-operatório de cirurgia cardíaca. Para fundamentar tal prática desenvolvemos o presente estudo. Este estudo tem como objetivo buscar na literatura as evidências disponíveis sobre os cuidados no descongelamento de homoenxertos em cirurgias de valvas cardíacas no período intra-operatório. Trata-se de uma revisão integrativa da literatura. As bases de dados selecionadas foram Medline e Lilacs e os descritores de assunto utilizados foram: transplante homólogo, criopreservação e valvas cardíacas. Foram incluídos na revisão sete artigos, os quais foram abordavam principalmente aspectos da técnica para o descongelamento do enxerto, o tempo para a realização deste procedimento e a solução empregada. Concluímos que a prática do descongelamento do homoenxerto fundamenta-se em estudos de nível de evidências 6 e 7 e abordaram pouco sobre a atuação da enfermagem.
The Less Invasive Anterior Approach for Total HIP Arthroplasty: A Comparison to other Approaches and an Evaluation of the Learning Curve - A Systematic Review
Authors: den Hartog Yvon M. , Mathijssen Nina M.C. , Vehmeijer Stephan B.W.
Published: March 2016

There is still discussion about possible advantages and disadvantages of the less invasive anterior approach for total hip arthroplasty (THA). The purpose of our systematic review was to evaluate literature regarding the anterior approach in comparison to other approaches. Furthermore, we investigated if there is a description of a learning curve for the anterior approach.

Data were obtained from EMBASE, Cochrane, PsycINFO, CINAHL, Web-of-Science, Scopus, Google scholar, and PubMed since their inception up to June 2015. 2 reviewers independently selected the studies and independently conducted the quality assessment. Because studies were considered heterogeneous regarding outcome measures, determinants studied, and methodological quality, we decided to perform a “best evidence synthesis”. A total of 64 studies met the inclusion criteria.

Strong evidence for no difference in component placement between the anterior approach and other approaches was found. Also, strong evidence for faster postoperative recovery and less need for assistive devices after the anterior approach were found. All other studied parameters only demonstrated conflicting evidence. Although the learning curve for the anterior approach is not yet clear, this learning curve should not to be neglected.

In conclusion, the less invasive anterior approach provides benefits in the early postoperative period only, when compared to other approaches.
Design and Evaluation of a Novel Subatmospheric Pressure Bioreactor for the Preconditioning of Tissue-Engineered Vascular Constructs
Authors: Coakley Daniel N. , Shaikh Faisal M. , O'Sullivan Kathleen , Kavanagh Eamon G. , Grace Pierce A. , McGloughlin Tim M.
Published: March 2016

Purpose

The pre-conditioning of tissue-engineered vascular scaffolds with mechanical stimuli is being recognised as an essential step in producing a functional vascular construct. In this study we design and evaluate a novel bioreactor, which exerts a mechanical strain on developing vascular scaffolds via subatmospheric pressure.

Methods

We design and construct a bioreactor, which exerts subatmospheric pressure via a vacuum assisted closure unit. Vascular scaffolds seeded with human umbilical endothelial cells were evaluated for structural integrity, microbial contamination, cellular viability, von Willebrand factor (VWF) production, cell proliferation and morphology under a range of subatmospheric pressures (75-200mmHg).

Results

The bioreactor produced sustained subatmospheric pressures, which exerted a mechanical strain on the vascular scaffold. No microbial contamination was found during the study. The structural integrity of the vascular construct was maintained. There was no difference in cellular viability between control or subatmospheric pressure groups (p = 0.817). Cells continued to produce VWF under a range of subatmospheric pressures. Cells subjected to subatmospheric pressures of 125mmHg and 200mmHg exhibited higher levels of growth than cells in atmospheric pressure at 24 (p≤0.016) and 48 hour (p≤0.001). Negative pressure affected cellular morphology, which were more organised, elongated and expanded when exposed to subatmospheric pressure.

Conclusions

We have constructed and validated a novel subatmospheric bioreactor. The bioreactor maintained a continuous subatmospheric pressure to the vascular scaffolds in a stable, sterile and constant environment. The bioreactor exerted a strain on the vascular sheets, which was shown to alter cellular morphology and enhance cellular proliferation.
Cost Calculations during “Dire Straits”: A Cost-of-Illness Analysis of Regular Hemodialysis for End-Stage Renal Disease in Greece
Authors: Naoum Panagiota , Topkaroglou Ioannis , Kitsonis Dimitrios , Skroumpelos Anastasios , Athanasakis Kostas , Iatrou Christos , Boletis John , Kyriopoulos John
Published: March 2016

Purpose

More than 3 million people worldwide suffer from end-stage renal disease (ESRD). Even though regular hemodialysis is considered very costly, it is still the most commonly used method of treatment in Greece. The aim of this study is to provide a current estimate of the annual patient cost for ESRD-related regular hemodialysis, especially during a period of economic instability for Greece.

Methods

Data was collected from 113 anonymous patient files from 3 dialysis units. The cost analysis includes the following parameters: hospitalization, disposable supplies, medication, meals, contaminants, human resources and equipment depreciation/utilization.

Results

The cost of a regular hemodialysis session was estimated at €177.12. Human resources account for 43.53% of the hemodialysis cost, while expendable supplies and medication account for 24.79% and 21.16%, respectively. The total annual cost of ESRD per patient was calculated at €34,012.31, which breaks down into €27,630.72 (81.24%) for hemodialysis, €4,800.64 (14.11%) for hospitalization, €1,454.84 (4.28%) for laboratory tests and €126.11 (0.37%) for microsurgery.

Conclusions

ESRD entails a significant economic burden for the Greek health care system. In a current context of ongoing austerity measures, which severely pressure the health care budget, further research should be performed in order to identify possible ways to reduce costs and improve management of the disease.
Association between VEGF-A, C and D Expression and lymph Node Involvement in Breast Cancer: A Meta-Analysis
Authors: Su Fei , Liu Baoquan , Chen Mingwei , Xiao Jianbing , Li Xuemei , Lv Xiaohong , Ma Jing , You Kai , Zhang Jianguo , Zhang Yafang
Published: March 2016

Background

Metastasis is the primary cause of death in patients with breast cancer. Although VEGF-A, C and D are considered to be prime factors in lymph node metastasis in breast cancer, the published studies have conflicting conclusions.

Methods

To resolve this conflict, we conducted a meta-analysis of 37 studies (n = 5,001 patients) evaluating the correlation between VEGF-A, C and D immunohistochemical expression and lymph node metastasis (LNM). The meta-analysis included 22 studies of VEGF-A, 17 of VEGF-C, and 6 of VEGF-D. The relationships between VEGF-A, C and D and clinicopathological parameters were also examined.

Results

The results showed a significant association between VEGF-A or VEGF-C overexpression and LNM (risk ratio [RR] = 1.28 [95% CI 1.04-1.58], p = 0.02; and RR = 1.36 [95% CI 1.07-1.72], p = 0.01, respectively). Subgroup evaluation showed a significant association between VEGF-A, C and D overexpression and LNM when analyses were limited to Asian patients (RR = 1.78 [95% CI 1.28-2.46], p = 0.0005; RR = 1.38 [95% CI 1.04-1.84], p = 0.03, and RR = 2.62 [95% CI 1.35-5.09], p = 0.004, respectively). VEGF-A overexpression was significantly associated with lymph vessel invasion (RR = 1.86 [95% CI 1.33-2.60], p = 0.0003). Overexpression of VEGF-C or VEGF-D was significantly associated with HER-2 positivity (RR = 1.30 [95% CI 1.06-1.59], p = 0.01; and RR = 1.75 [95% CI 1.01-3.03], p = 0.05, respectively).

Conclusions

With some limitations, our meta-analysis indicated that VEGF-A and C could predict LNM in patients with breast cancer, particularly Asian patients.
Polymorphisms in Cancer Susceptibility Genes XRCC1, RAD51 and TP53 and the Risk of Breast Cancer in Serbian Women
Authors: Krivokuca Ana M. , Cavic Milena R. , Malisic Emina J. , Rakobradovic Jelena D. , Kolarevic-Ivankovic Daniela , Tomasevic Zorica I. , Brankovic-Magic Mirjana V.
Published: March 2016

Background

Thanks to immense improvements in technology over the past few decades, we have witnessed a major shift towards the idea that breast cancer results from a combined effect of multiple common alleles conferring low risk. This study investigates the role of 3 nonsynonymous SNPs in the DNA repair genes XRCC1 (R399Q), RAD51 (G135C) and TP53 (Arg72Pro) in breast cancer in Serbian women.

Patients and Methods

Cases of BRCA1/2-negative hereditary breast cancer (n = 52), sporadic breast cancer (n = 106) and age-matched cancer-free female controls (n = 104) were obtained from the Institute for Oncology and Radiology of Serbia's blood bank. Restriction fragment length polymorphism analysis was used for genotyping. Descriptive analyses included genotype and allelic frequencies; the odds ratio and 95% confidence interval were calculated as an estimate of the relative risk.

Results

A significant difference in QQ+RQ versus RR genotype distribution of XRCC1 was observed between hereditary breast cancer patients and cancer-free controls. The association was confirmed among young breast cancer patients from these high-risk families. The existence of 3 recessive alleles in the RAD51 and XRCC1 genotype combination showed an association with hereditary breast cancer. Odds ratio analysis indicated a strong protective role of the RAD51 GG + TP53 ArgArg + XRCC1 RR combined genotype against hereditary breast cancer negative for BRCA1/2 mutations.

Conclusions

The XRCC1 R399Q polymorphism showed an association with increased breast cancer risk in Serbia, especially in the hereditary form of the disease and in young breast cancer patients. Dominant alleles of RAD51, TP53 and XRCC1 combined genotypes indicated a strong protective role against hereditary breast cancer.
Pleomorphic Rhabdomyosarcoma with an Impressive Response to Chemotherapy: Case Report and Review of the Literature
Authors: Kollár Attila , Langer Rupert , Ionescu Codruta , Cullmann Jennifer L. , Klenke Frank M.
Published: March 2016

Purpose

Pleomorphic rhabdomyosarcoma (RMS) represents a rare sarcoma subtype of the adult population. Due to its clinical characteristics, treatment is currently based on the guidelines for adult soft tissue sarcoma therapy. Hence, in the metastatic setting, doxorubicin-containing regimens are used in the sarcoma community, with limited treatment benefit. Scanty published data are available on the efficacy of systemic treatment. Whether treatment response and outcome of these patients could be improved by using pediatric protocols used typically in other RMS subtypes, like embryonal and alveolar RMS, is unclear. We report on an impressive effect of multiagent pediatric chemotherapy in an adult patient with metastatic pleomorphic RMS.

Methods

We present the case of a 70-year-old man with metastatic pleomorphic RMS of his left thigh. Systemic chemotherapy according to the VAC regimen (vincristine, actinomycin, cyclophosphamide) was initiated. Follow-up clinical and radiologic assessment demonstrated an impressive treatment response.

Results

Sixteen months after primary diagnosis, computed tomography scan shows no signs of tumor progression.

Conclusions

Our case report emphasizes that multiagent systemic therapy according to pediatric protocols should be considered in adult patients with pleomorphic RMS.
A escola na visão dos estudantes da educação de jovens e adultos: narrativas e perspectivas
Authors: Pires João Davi Avelar , Alegro Regina Célia Célia
Published: March 2016

Tendo por base a valorização e a importância que se tem dado aos conhecimentos prévios, anteriores ao ensino formal, e às narrativas dos estudantes nas últimas décadas, este trabalho apresenta uma sucinta análise de narrativas colhidas entre frequentadores da Educação de Jovens e Adultos (EJA) em cidades do norte paranaense. Tentamos identificar as ideias, concepções e representações que estes possuem sobre a escola e o espaço escolar considerado como ideal, bem como sua finalidade, as relações sociais que se estabelecem e o público para o qual a instituição escolar se destina. Trabalhamos, portanto, com narrativas de estudantes enquanto um tipo de linguagem, escrita, construída através da memória e também de construções e reconstruções pessoais, que podem nos fornecer indícios do que eles pensam e de que tipos de interpretação possuem. Entendemos como característica principal da narrativa seu esforço construtivo, na medida em que pensamentos, interpretações e representações sociais que se encontram presentes na estrutura cognitiva do sujeito devem ser sistematizados e ordenados, numa escrita que faça sentido e que consiga apresentar determinada visão de mundo. Destas narrativas, foram criadas categorias, a partir de aspectos comuns, e divididas por representações sobre a escola, finalidades da escola e relações entre alunos e professores.
Greek National E-Prescribing System: Preliminary Results of a Tool for Rationalizing Pharmaceutical Use and Cost
Authors: Polyzos Nikolaos , Kastanioti Catherine , Zilidis Christos , Mavridoglou George , Karakolias Stefanos , Litsa Panagiota , Menegakis Valantis , Kani Chara
Published: March 2016

BACKGROUND: In Greece, due to the ongoing economic crisis a number of measures aiming at rationalising expenditure implemented. A new e-prescribing system, under a unified healthcare fund was the main pillar of these reforms focus on monitoring and auditing prescribing patterns.

OBJECTIVE: Main objective of this study was to document the Greek experience with the new national e-prescribing system.

METHODS: We analyse the dispensed prescriptions over the period 2013-2014, stratified into four levels: therapeutic subgroup, patent status, physician's specialty and geographical region.

RESULTS: Data analysis offered a comprehensive insight into pharmaceutical expenditure over the timeframe and revealed discrepancies regarding composition of spending, brand-generic substitution within certain therapeutic subgroups, physicians’ prescribing behaviour based on medical specialty, therapeutic subgroup as well as regional per capita measures.

CONCLUSIONS: E-prescribing system is a valuable tool providing sound information to health policymakers in order to monitor and rationalize pharmaceutical expenditure, in value and volume terms.
Relationship between General Health Indices and Sexual Dysfunction in Women Experiencing Spousal Abuse
Authors: Shayan Arezoo , Kaviani Masoumeh , Azima Sara , Masoumi Seyedeh Zahra , Panah Sezaneh Hagh , Gholamzadeh Saeed , Zarenezhad Mohamad
Published: March 2016

BACKGROUND: Sexual behavior is among the complex dimensions of humans. Various factors are effective in sexual function. Sexual dysfunction affects people's mental health.

OBJECTIVES: The present study aims to determine the relationship between general health indices and sexual dysfunction among the women referring to Shiraz Forensic Medicine Center, Iran.

METHODS: This cross-sectional, descriptive-analytical study was conducted on 197 women experiencing spousal abuse who had referred to Shiraz Forensic Medicine Center in 2014. The data were collected using demographic information questionnaire, a questionnaire assessing violence against women, general health questionnaire (GHQ-28), and female sexual function index (FSFI). The data were entered into SPSS statistical software and analyzed using t-test, Chi-square test, Pearson's correlation coefficient, and regression analysis.

RESULTS: Based on the results, 91.9% of the participants had sexual dysfunction and 85.3% had mental disorders. Besides, a significant relationship was found between sexual dysfunction and somatic symptoms (P=0.027), anxiety and insomnia (P=0.004), as well as overall general health (P=0.041). Also, the results of Pearson's correlation test revealed significant associations between various dimensions of sexual dysfunction and general health.

CONCLUSION: According to the results, physical and mental health seems to play a critical role in determining sexual dysfunction. Thus, the identification and treatment of physical and mental disorders are recommended for the patients suffering from sexual dysfunction.
Does Salivary Calcium and Phosphate Concentrations Adequately Reflect Bone Mineral Density in Patients with Chronic Periodontitis?
Authors: Moghadam Somaye Ansari , Zakeri Zahra , Fakour Sirous Risbaf , Moghaddam Alireza Ansari
Published: March 2016

BACKGROUND: Periodontitis is the inflammation of the periodontal supporting tissues. The response of periodontal tissues to local bacteria leads to bone resorption and destruction of periodontal junction. Given the possible association between periodontitis and low bone mineral density, the aim of present study was to find if measurement of salivary biomarkers as a less invasive method, can provide an appropriate screening method for assessment of bone mineral density in patients with chronic periodontitis?

METHODS: A case-control study was conducted on 53 people, including 28 patients with severe chronic periodontitis and 25 healthy people between April 2014 to March 2015 in Zahedan (southeast of Iran). Following Periodontal examination, salivary samples were collected, and the concentration of salivary calcium and phosphate were measured and reported as mg/dl. Bone mineral density of participants was measured using dual energy x-ray absorptiometry and reported as gr/cm2.

RESULTS: No significant association was found between concentrations of salivary calcium and phosphate levels with bone mineral density in either healthy people or in patients with severe chronic periodontitis, despite a significant bone density reduction (in the femur neck and lumbar spine L2-L4) in the periodontitis group compared to healthy people (P=0.006, and P=0.009 respectively).

CONCLUSION: Concentration of salivary calcium and phosphate do not appear to be good indicators of bone mineral density. Further prospective studies with larger sample size are recommended.
Patulin, Deoxynivalenol, Zearalenone and T-2 Toxin Affect Viability and Modulate Cytokine Secretion in J774A.1 Murine Macrophages
Authors: Loftus Jonathan H. , Kijanka Gregor S. , O’Kennedy Richard , Loscher Christine E.
Published: March 2016

Mycotoxins are secondary fungal metabolites, which occur in food and feed. They have detrimental effects on the health of humans and animals, and they are known to cause immunosuppression. In this study the effect of patulin, deoxynivalenol (DON), zearalenone (ZEN) and T-2 toxin exposure on the viability and the secretion of key pro- and anti-inflammatory cytokines from the murine macrophage cell line, J774A.1, was investigated.  Exposure of macrophages to high doses of ZEN (100,000 pg/mL) and T-2 toxin (10,000 and 100,000 pg/mL) resulted in a significant decrease (P < 0.05 and P < 0.01) in cell viability. Exposure of macrophages to these mycotoxins resulted in a dose-dependent modulation of cytokine secretion. Specifically, exposure to low doses of patulin (0.001, 0.1 and 1 pg/mL) resulted in a statistically significant decrease in the secretion of the pro-inflammatory cytokines interleukin (IL) 6 (IL-6) and tumor necrosis factor alpha (TNF-α), following stimulation with lipopolysaccharide (LPS), a component of Gram-negative bacterial cell walls. Treatment with low doses of DON (0.001 pg/mL) and ZEN (0.001 and 0.01 pg/mL) significantly decreased (P < 0.01) the secretion of the pro-inflammatory cytokine IL-12p40, while several doses of T-2 toxin (0.001, 0.01, 0.1, 1 and 100 pg/mL) caused a significant decrease the expression of IL-6. Each of the mycotoxins also significantly increased the production of the anti-inflammatory cytokine IL-10, both before and after LPS stimulation. This data provides further insight into the mechanisms by which mycotoxins modulate the host immune response to exert their immunosuppressive activity.
Evaluation and Management of the Physicochemical Variables of Asu River, Southeast, Nigeria
Authors: Joshua Nwinyimagu Amaechi , Nkwuda Nwonumara Godwin , Chijioke Ani , Ogeze Ukeje Ikechukwu
Published: March 2016

Asu River is one of the major tributaries of Cross River, a tropical reforest river in southeast Nigeria. The climate of the region is divided into the wet and dry seasons. Human activities such as fishing, bathing and washing go on in the river especially during the dry season. Farming also takes place at the fringes of the river. Some important physicochemical parameters of the river were investigated at two designated sites comprising the downstream and the upstream for nine (9) months, from October, 2013 to June, 2014. Temperature, carbon (iv) oxide, conductivity, total dissolved solids, nitrate and phosphate recorded maximum values during the dry season while dissolved oxygen and pH recorded maximum values in the wet season. The physicochemical variables evaluated showed that the river is not in a critical condition as most of the variables recorded are within the WHO permissible limit. However, the paper therefore recommends the need for public enlightenment on environmental management and control of household and industrial wastes in order to sustain the usefulness of Asu River.