bluuebunny/crossref_metadata_2025 huggingface dataset:
CAPM Indexed Hybrid E-Negotiation for Resource Allocation in Grid Computing
Authors: Rahman Ashiqur Md. , Rahman Rashedur M
Published: August 2013

Computational Grids are a promising platform for executing large-scale resource intensive applications. This paper identifies challenges in managing resources in a Grid computing environment and proposes computational economy as a metaphor for effective management of resources and application scheduling. It identifies distributed resource management challenges and requirements of economy-based Grid systems, and proposes an economy based negotiation system protocol for cooperative and competitive trading of resources. Dynamic pricing for services and good level of Pareto optimality make auctions more attractive for resource allocation over other economic models. In a complex Grid environment, the communication demand can become a bottleneck; that is, a number of messages need to be exchanged for matching suitable service providers and consumers. The Fuzzy Trust integrated hybrid Capital Asset Pricing Model (CAPM) shows the higher user centric satisfaction and provides the equilibrium relationship between the expected return and risk on investments. This paper also presents an analysis on the communication requirements and the necessity of the CAPMAuction in Grid environment.
Decision Making Process Approach for Choosing the Adequate ICT Tool in Virtual Teams
Authors: Draghici Anca , Aldea Cosmina Carmen , Draghici George
Published: August 2013

Actual business process activities are done in virtual space by teams that are building, exploiting an adequate collaborative environment. This is defined mainly by the specific information and communication technology (ICT) enabled by Internet/Extranet/Intranet. The ICT tools functionalities have been developed to better satisfy virtual teams requirements related to knowledge management activities. In this context, this article presents a brief state-of-the-art of virtual teams’ definitions and characteristics that reinforce them with efficiency-effectiveness. Foreword, because of the large variety of ICT tools available to support virtual collaboration, the authors proposed an approach for the decision making process of choosing the adequate software solution based on the particular needs and requirement determined by the collaborative environment specificity. Assisting this, there will be analyzed the specific software tool’s main functionalities that are correlated with the virtual teams requirements. This is the main step for the decision making process approach definition in order to choose the adequate software solution, using ELECTRE method (decision under conditions of certainty).
A Novel Graphical-Oriented Framework for Capturing Data within Clinical Information Systems
Authors: Jahedi Farzad , Maghsoudloo Mehran , Amirchakhmaghi Medhi
Published: August 2013

One of the main challenges in the development and implementation of computerized health care systems is the physicians and nurses’ resistance, stemming in particular from the use of text based environments for the capture of their medical examination data. The purpose of the present study was to propose the basis for a graphical oriented framework which can be used to capture data for a medical examination therefore easing the data-entry using the keyboard. Following analysis of a classical general medical examination, an XML schema was designed to describe physical examinations. Based on the physical examination XML schema, XML data structures are transformed to HTML using XML transformation style sheets to create dynamic graphical user interface (GUI) widgets; user interactions with the widgets leads to the generation of sentences. The key advantages of the proposed system are: a) a reduction in the keyboard usage, b) the ability to codify the generation sentence accurately and c) an operating system platform independence. A prototype of usage of the above framework is also presented.
Implication of E-Health and IT Governance on Healthcare Expenditure
Authors: Sadr Seyed Shahabeddin , Sadr Seyed Mohammad Hossein , Farahani Yazdan Gudarzi
Published: August 2013

This paper analyzes the public healthcare expenditure of Middle Eastern countries in relation to different exogenous explanatory variables, through a panel study involving twelve (12) Middle East countries. More specifically, the study methodology uses panel cointegration, and panel-based error correction models derived from annual data covering the period of 2000 to 2010. The empirical results support a short-run co-integration relationship after allowing for the heterogeneous country effect. The long-run relationship is estimated using a full-modified OLS. The results of a ten-year panel study have been interpreted and commented. The public healthcare expenditure of our countries is explicated to a great extent by the single country GDP. Other strong correlation variables were found also to be statistically significant. The research reveals that e-health programming and e-health governance could lead to a decrease in unnecessary health care expenditure.
The Business Values of Patient Knowledge Management (PKM) in the Healthcare Industry
Authors: Delgosha Mohammad Soltani , Ojaki Ali Amoei , Farhadi Hamidreza
Published: August 2013

Today, healthcare has become a progressive industry with novel techniques, approaches and findings in this field quickly being evaluated and improved. One of these approaches is patient-centered care (PCC), which is defined essentially as an approach that respects and responds to individual patient’s preferences, needs and values. As such, PCC concept focuses not only on the disease, but also on leveraging specific information of a patient. PCC approach is therefore going to enlarge the role of patients and families in the process of clinical decision making. Still, the authors are observing the lack of innovation in this particular domain. In this paper, the authors develop the concept of patient knowledge management (PKM) based on customer knowledge management and PCC approaches. PKM creates many values such as decreasing opportunity costs and treatment costs, aiding patient decision making to be efficient and effective, as well as creating new knowledge and developing new treatment methods.
Audio Classification and Retrieval Using Wavelets and Gaussian Mixture Models
Authors: Chuan Ching-Hua
Published: August 2013

This paper presents an audio classification and retrieval system using wavelets for extracting low-level acoustic features. The author performed multiple-level decomposition using discrete wavelet transform to extract acoustic features from audio recordings at different scales and times. The extracted features are then translated into a compact vector representation. Gaussian mixture models with expectation maximization algorithm are used to build models for audio classes and individual audio examples. The system is evaluated using three audio classification tasks: speech/music, male/female speech, and music genre. They also show how wavelets and Gaussian mixture models are used for class-based audio retrieval in two approaches: indexing using only wavelets versus indexing by Gaussian components. By evaluating the system through 10-fold cross-validation, the author shows the promising capability of wavelets and Gaussian mixture models for audio classification and retrieval. They also compare how parameters including frame size, wavelet level, Gaussian components, and sampling size affect performance in Gaussian models.
Rule-Based Semantic Concept Classification from Large-Scale Video Collections
Authors: Lin Lin , Shyu Mei-Ling , Chen Shu-Ching
Published: August 2013

The explosive growth and increasing complexity of the multimedia data have created a high demand of multimedia services and applications in various areas so that people can access and distribute the data easily. Unfortunately, traditional keyword-based information retrieval is no longer suitable. Instead, multimedia data mining and content-based multimedia information retrieval have become the key technologies in modern societies. Among many data mining techniques, association rule mining (ARM) is considered one of the most popular approaches to extract useful information from multimedia data in terms of relationships between variables. In this paper, a novel rule-based semantic concept classification framework using weighted association rule mining (WARM), capturing the significance degrees of the feature-value pairs to improve the applicability of ARM, is proposed to deal with major issues and challenges in large-scale video semantic concept classification. Unlike traditional ARM that the rules are generated by frequency count and the items existing in one rule are equally important, our proposed WARM algorithm utilizes multiple correspondence analysis (MCA) to explore the relationships among features and concepts and to signify different contributions of the features in rule generation. To the authors best knowledge, this is one of the first WARM-based classifiers in the field of multimedia concept retrieval. The experimental results on the benchmark TRECVID data demonstrate that the proposed framework is able to handle large-scale and imbalanced video data with promising classification and retrieval performance.
A Rare Case of Multiple Jejunal Diverticulosis Presenting as Intestinal Obstruction
Authors: Tiwari Alok Kumar , Gupta Vijay , Hazrah Priya , Lal Romesh
Published: August 2013

Diverticulosis is rare in jejunum and its unusual presentation of mechanical obstruction is difficult to diagnose pre-operatively. We report a case of a 54-year old male patient who had symptoms of general abdominal pain and vomiting off and on for three years. He had been assessed elsewhere and had received a course of anti-tubercular treatment empirically based on features of recurrent intestinal obstruction due to prevalence of tuberculosis in this region. The patient had presented himself with signs and symptoms of dynamic intestinal obstruction. On examination, the abdomen was found to be swollen with a central abdominal distension and hyperactive bowel sounds. The erect abdominal radiograph showed multiple air-fluid levels and dilated jejunal loops. Following this, the patient underwent an emergency exploratory laparotomy. This revealed multiple jejunal diverticulae, multiple bands and adhesions involving jejunum and proximal ileum. The bands and adhesions were removed and the jejunum was resected along with the inflamed diverticulae.
Intrauterine Growth Restriction Associated with Excessively Long Umbilical Cord
Authors: Schmid Ann , Jacquemyn Yves , De Loor Jeannette
Published: August 2013

We present a 37-week female baby, known with intrauterine growth restriction since 25 weeks of pregnancy, born with a placenta with an excessive long umbilical cord (ELUC), without any other abnormalities. ELUC is mostly an incidental finding after delivery, but represents a potentially detectable intrauterine cause of growth restriction. A system that allows ultrasound measurement of the length of the umbilical cord could highly increase antenatal diagnosis of ELUC.
The convergence of systemic threads shaping a future South African healthcare dispensation: A technology management perspective
Authors: Weeks Richard
Published: August 2013

Orientation: Underpinning healthcare service delivery are a number of support systems. This paper focuses on the development of a healthcare services framework that reflects the systems that need to be integrated, from a technology healthcare support perspective.Research purpose: The purpose of this paper is gain an understanding of some of the intricacies associated with the management of the transition to a future South African healthcare dispensation, with reference to the convergence of technology, financial healthcare and socio-political systems.Motivation for the study: South Africa is in the process of implementing the National Health Insurance initiative and the approach adopted will have a significant impact on the business model design.Research design, approach and method: A multidisciplinary literature study was undertaken. In addition, a limited narrative enquiry was also conducted. Practitioners interviewed were from the healthcare, informatics and management and technology sectors respectively. The research study constituted an insight study – analytically descriptive and not statistical in nature.Main findings: The literature reflects two very contrasting and different business models of healthcare service provision, namely a primarily curative and preventative stance. Each assumes a very different convergence of technology, healthcare, financial and social systems and consequently gives rise to contrasting business models. The dominant model appears to be based on primary healthcare, with a different technology support infrastructure to the previously-adopted curative approach. It is a model that would also appear to necessitate a complex adaptive management approach, necessitating a bottom-up as opposed to a top-down hierarchal management orientation.Contribution/Value-add: The National Healthcare Insurance initiative entails a very fundamental restructuring of the healthcare infrastructure. The insights gained from this research study could serve as a source of information and reference for South African institutions that will need to implement such systems in the future.
YHWH, the God of new beginnings: Micah’s testimony
Authors: Wessels Wilhelm
Published: August 2013

The book of Micah is known for its judgement oracles against the leadership structures in the Southern Kingdom, Judah. Besides the judgement oracles, however, the book also contains oracles of salvation. Scholars have noted and commented on this interruption of predominant judgement oracles by oracles of salvation. The composition of the book has been scrutinised, with many scholars suggesting that the salvation oracles were inserted later to soften the harsh, condemning nature of the book. For the purposes of this article I would like to propose a theological reading of the juxtaposition of Micah 3:12 and 4:1, two passages containing judgement and salvation oracles respectively. The solutions offered to explain the drastic contrast between these two passages have to a great extent reached an impasse. However, from a theological perspective, I argue that these two radically contradictory messages are a reflection of the very nature of YHWH’s interaction with his people. Micah 3:12 reflects a point in history where YHWH has had enough of morally corrupt leaders and people, and announces that he is bringing matters to a painful end. However, YHWH is also the God of new beginnings. He states in Micah 4:1ff. that there will come a day when things will change for the better for the people of Judah and that a time of restoration will come for his people. His desire remains to be their God and to restore them to be his people. The article seeks to show that this example, which reflects YHWH as the God of new beginnings, is not an isolated example in the prophetic literature, but consistent with YHWH’s nature.
Will woody plant encroachment impact the visitor experience and economy of conservation areas?
Authors: Gray Emma F. , Bond William J.
Published: August 2013

Woody plant encroachment into savannas is a globally prevalent phenomenon and impacts ecosystem goods and services such as biodiversity, carbon storage, nutrient cycling, grazing and hydrology. The direct ecological and economic consequences for rangelands have been fairly well studied, but, to our knowledge, the economic impact on conservation efforts has not been investigated. African savannas are important as conservation areas because they support large numbers of the world’s remaining megafauna. This study used visitor surveys and long-term mammal distribution data to investigate how an increase in tree density might affect the visibility of animals in a conservation area, which could reduce the satisfaction of visitors to the area. We found that apparent herd sizes and density of animals were much reduced in woody areas, suggesting that visibility is negatively impacted. Visitor surveys determined that a large fraction (almost half) of potential future visitors to the park may be lost if animals became more difficult to see and that the majority of these would be the higher-spending visitors. Responses differed depending on the origin of visitors, with international visitors being more interested in seeing animals, whilst local visitors were more content with just being away from the city. The results suggest that woody plant encroachment may have significant impacts on visitor numbers to savanna conservation areas, whilst animal numbers and densities may also be significantly impacted.Conservation implications: The results pointed to potentially significant economic consequences for conservation efforts as visitors become less satisfied with their experience. Perceptions of visitors are important for management decisions as park fees contribute significantly to conservation efforts. This could ultimately result in a reduced capacity for African conservation areas to conserve their biodiversity effectively. The results suggest that management may need to re-evaluate their approach to controlling woody plant encroachment.
Kinematics and Mechanical Properties Analyses on Vibration Converter of Intelligent Damper for Drill Strings
Authors: Zhu Xiaohua , Lai Chunlin
Published: August 2013

Taking vibration converter of intelligent damper for drill strings as the study object, this paper analyzes the influential factors of motion state of the ball and conducts an explicit dynamics simulation by establishing a mechanics model of vibration converter. The study basis is Newton’s laws of motion, d’alembert’s principle and hertz contact theory. and we use world coordinate system, rotating coordinate system and Frenet coordinate system to deduce kinematics equations of vibration converter. The ultimate result demonstrates that the axial velocity and maximum contact stress change with the increment of ball diameter and helix angle.It also proves the validity of our derived kinematics and mechanical models and provides a good consultant value for the design and theoretical arithmetic of vibration converter for intelligent damper of drill strings.
Cell Conservative Flux Recovery and A Posteriori Error Estimate of Vertex-Centered Finite Volume Methods
Authors: Chen Long , Wang Ming
Published: August 2013

A cell conservative flux recovery technique is developed here for vertex-centered finite volume methods of second order elliptic equations. It is based on solving a local Neumann problem on each control volume using mixed finite element methods. The recovered flux is used to construct a constant freea posteriorierror estimator which is proven to be reliable and efficient. Some numerical tests are presented to confirm the theoretical results. Our method works for general order finite volume methods and the recovery-based and residual-baseda posteriorierror estimators is the first result ona posteriorierror estimators for high order finite volume methods.
A Priori Error Estimates of Crank-Nicolson Finite Volume Element Method for Parabolic Optimal Control Problems
Authors: Luo Xianbing , Chen Yanping , Huang Yunqing
Published: August 2013

In this paper, the Crank-Nicolson linear finite volume element method is applied to solve the distributed optimal control problems governed by a parabolic equation. The optimal convergent orderO(h2+k2) is obtained for the numerical solution in a discreteL2-norm. A numerical experiment is presented to test the theoretical result.
Projections of atmospheric mercury levels and their effect on air quality in the United States
Authors: Lei H. , Wuebbles D. J. , Liang X.-Z. , Tao Z. , Olsen S. , Artz R. , Ren X. , Cohen M.
Published: August 2013

Abstract. The individual and combined effects of global climate change and emissions changes from 2000 to 2050 on atmospheric mercury levels in the US are investigated by using the global climate-chemistry model, CAM-chem, coupled with a mercury chemistry-physics mechanism (CAM-Chem/Hg). Three future pathways from the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) are considered, with the A1FI, A1B and B1 scenarios representing the upper, middle and lower bounds of potential climate warming, respectively. The anthropogenic and biomass burning emissions of mercury are projected from the energy use assumptions in the IPCC SRES report. Natural emissions from both land and ocean sources are projected using dynamic schemes. The zonal mean surface total gaseous mercury (TGM) concentrations in the tropics and mid-latitudes of the Southern Hemisphere are projected to increase by 0.5–1.2 ng m-3 in 2050. TGM concentration increases are greater in the low latitudes than they are in the high latitudes, indicative of a larger meridional gradient than in the present day. In the A1FI scenario, TGM concentrations in 2050 are projected to increase by 2.1–4.0 ng m-3 for the eastern US and 1.4–3.0 ng m-3 for the western US. This pattern corresponds to potential increases in wet deposition of 10–14 μg m-2 for the eastern US and 2–4 μg m-2 for the western US. The increase in Hg(II) emissions tends to enhance wet deposition and hence increase the risk of higher mercury entering the hydrological cycle and ecosystems. In the B1 scenario, mercury concentrations in 2050 are similar to present level concentrations; this indicates that the domestic reduction in mercury emissions is essentially counteracted by the effects of climate warming and emissions increases in other regions. The sensitivity analyses presented show that anthropogenic emissions changes contribute 32–53% of projected mercury air concentration changes, while the independent contribution by climate change accounts for 47–68%. In summary, global climate change could have a comparable effect on mercury pollution in the US to that caused by global emissions changes.
Coupled regional climate–ice-sheet simulation shows limited Greenland ice loss during the Eemian
Authors: Helsen M. M. , van de Berg W. J. , van de Wal R. S. W. , van den Broeke M. R. , Oerlemans J.
Published: August 2013

Abstract. During the last interglacial period (Eemian, 130–115 kyr BP) eustatic global sea level likely peaked at > 6 m above the present-day level, but estimates of the contribution of the Greenland Ice Sheet vary widely. Here we use an asynchronously two-way-coupled regional climate–ice-sheet model, which includes physically realistic feedbacks between the changing ice sheet topography and climate forcing. Our simulation results in a contribution from the Greenland Ice Sheet to the Eemian sea level highstand between 1.2 and 3.5 m, with a most likely value of 2.1 m. Simulated Eemian ice loss in Greenland is dominated by the rapid retreat of the southwestern margin; two-thirds of the ice loss occurred south of 70° N. The southern dome survived the Eemian and remained connected to the central dome. Large-scale ice sheet retreat is prevented in areas with high accumulation. Our results broadly agree with ice-core-inferred elevation changes and marine records, but it does not match with the ice-core-derived temperature record from northern Greenland. During maximum Eemian summertime insolation, Greenland mass loss contributed ~ 0.5 m kyr−1 to sea level rise, 24% of the reconstructed total rate of sea level rise. Next to that, a difference of > 3 m remains between our maximum estimate of the Greenland contribution and the reconstructed minimum value of the global eustatic Eemian highstand. Hence, the Antarctic Ice Sheet must also have contributed significantly to this sea level highstand.
Winter measurements of biogeochemical parameters in the Rockall Trough (2009–2012)
Authors: McGrath T. , Kivimäe C. , McGovern E. , Cave R. R. , Joyce E.
Published: August 2013

Abstract. This paper describes the sampling and analysis of biogeochemical parameters collected in the Rockall Trough in January/February of 2009, 2010, 2011 and 2012. Sampling was carried out across two transects, one southern and one northern transect each year. Samples for dissolved inorganic carbon (DIC) and total alkalinity (TA) were taken alongside salinity, dissolved oxygen and dissolved inorganic nutrients (total-oxidised nitrogen, nitrite, phosphate and silicate) to describe the chemical signatures of the various water masses in the region. These were taken at regular intervals through the water column. The 2009 and 2010 data are available on the CDIAC database.
High resolution air quality simulation over Europe with the chemistry transport model CHIMERE
Authors: Terrenoire E. , Bessagnet B. , Rouïl L. , Tognet F. , Pirovano G. , Létinois L. , Colette A. , Thunis P. , Amann M. , Menut L.
Published: August 2013

Abstract. A high resolution air quality simulation (0.125° × 0.0625° horizontal resolution) performed over Europe for the year 2009 has been evaluated using both rural and urban background stations available over most of the domain. Using seasonal and yearly mean statistical indicators such as the correlation index, the fractional bias and the root mean squared error; we interpret objectively the performance of the simulation. Positive outcomes are: a very good reproduction of the daily variability at UB sites for O3 (R =0.73) as well as for NO2 (R =0.61); a very low bias calculated at UB stations for PM2.5 (FB = −6.4%) and PM10 concentrations (FB = −20.1%). Conversely, main weaknesses in model performance include: the underestimation of the NO2 daily maxima at UB site (FB = −53.6%); an overall underestimation of PM10 and PM2.5 concentrations observed over Eastern European countries (e.g. Poland); the overestimation of sulphates concentrations at spring time (FB = 53.7%); finally, over the year, total nitrate and ammonia concentrations are better reproduced than nitrate and ammonium aerosol phase compounds. Obtained results suggest that, in order to improve the model performances, efforts should focus on the improvement of the emission inventory quality for Eastern Europeans countries and the improvement of a specific parameterisation in the model to better account for the urban effect on meteorology and air pollutants concentrations.
Frontiers in air quality modelling
Authors: Colette A. , Bessagnet B. , Meleux F. , Rouïl L.
Published: August 2013

Abstract. The first pan-European kilometre-scale atmospheric chemistry simulation is introduced. The continental-scale air pollution episode of January 2009 is modelled with the CHIMERE offline chemistry-transport model with a massive grid of 2 million horizontal points, performed on 2000 CPU of a high performance computing system hosted by the Research and Technology Computing Center at the French Alternative Energies and Atomic Energy Commission (CCRT/CEA). Besides the technical challenge, we find that model biases are significantly reduced, especially over urban areas. The high resolution grid also allows revisiting the contribution of individual city plumes to the European burden of pollution, providing new insights for designing air pollution control strategies.
A study on WRF radar data assimilation for hydrological rainfall prediction
Authors: Liu J. , Bray M. , Han D.
Published: August 2013

Abstract. Mesoscale numerical weather prediction (NWP) models are gaining more attention in providing high-resolution rainfall forecasts at the catchment scale for real-time flood forecasting. The model accuracy is however negatively affected by the "spin-up" effect and errors in the initial and lateral boundary conditions. Synoptic studies in the meteorological area have shown that the assimilation of operational observations, especially the weather radar data, can improve the reliability of the rainfall forecasts from the NWP models. This study aims at investigating the potential of radar data assimilation in improving the NWP rainfall forecasts that have direct benefits for hydrological applications. The Weather Research and Forecasting (WRF) model is adopted to generate 10 km rainfall forecasts for a 24 h storm event in the Brue catchment (135.2 km2) located in southwest England. Radar reflectivity from the lowest scan elevation of a C-band weather radar is assimilated by using the three-dimensional variational (3D-Var) data-assimilation technique. Considering the unsatisfactory quality of radar data compared to the rain gauge observations, the radar data are assimilated in both the original form and an improved form based on a real-time correction ratio developed according to the rain gauge observations. Traditional meteorological observations including the surface and upper-air measurements of pressure, temperature, humidity and wind speed are also assimilated as a bench mark to better evaluate and test the potential of radar data assimilation. Four modes of data assimilation are thus carried out on different types/combinations of observations: (1) traditional meteorological data; (2) radar reflectivity; (3) corrected radar reflectivity; (4) a combination of the original reflectivity and meteorological data; and (5) a combination of the corrected reflectivity and meteorological data. The WRF rainfall forecasts before and after different modes of data assimilation are evaluated by examining the rainfall temporal variations and total amounts which have direct impacts on rainfall–runoff transformation in hydrological applications. It is found that by solely assimilating radar data, the improvement of rainfall forecasts are not as obvious as assimilating meteorological data; whereas the positive effect of radar data can be seen when combined with the traditional meteorological data, which leads to the best rainfall forecasts among the five modes. To further improve the effect of radar data assimilation, limitations of the radar correction ratio developed in this study are discussed and suggestions are made on more efficient utilisation of radar data in NWP data assimilation.
Assessing accuracy of gas-driven permeability measurements: a comparative study of diverse Hassler-cell and probe permeameter devices
Authors: Filomena C. M. , Hornung J. , Stollhofen H.
Published: August 2013

Abstract. Permeability is one of the most important petrophysical parameters to describe the reservoir potential of sedimentary rocks, contributing to problems in hydrology, geothermics, or hydrocarbon reservoir analysis. Outcrop analog studies, well core measurements, or individual sample analysis take advantage of a variety of commercially available devices for permeability measurements. Very often, permeability data derived from different devices need to be merged within one study, e.g. outcrop mini-permeametry and lab-based core plug measurements. To enhance accuracy of different gas-driven permeability measurements, device-specific aberrations need to be taken into account. The application of simple one-to-one correlations may draw a wrong picture of permeability trends. For this purpose, transform equations need to be established. This study presents a detailed comparison of permeability data derived from a selection of commonly used Hassler cells and probe permeameters. As a result of individual cross-plots, typical aberrations and transform equations are elaborated which enable corrections for the specific permeameters. Permeability measurements of the commercially available ErgoTech Gas Permeameter and the TinyPerm II probe-permeameter are well-comparable over the entire range of permeability, with R2 = 0.967. Major aberrations are identified among the TinyPerm II and the mini-permeameter/Hassler-cell combination at Darmstadt University, which need to be corrected and standardized within one study. However, transforms are critical to their use, as aberrations are frequently limited to certain permeability intervals. In the presented examples, deviations typically tend to occur in the lower permeability range < 10 mD. Applying standardizations which consider these aberration intervals strongly improve the comparability of permeability datasets and facilitate the combination of measurement principles. Therefore, the utilization of such correlation tests is highly recommended for all kinds of reservoir studies using integrated permeability databases.
Efficacy of Timolol 0.1% Gel and a Prostaglandin Analog in an Unfixed Combination Compared to the Corresponding Fixed Combinations
Authors: Nucci Carlo , Varesi Chiara , Martucci Alessio , Cesareo Massimo , Cedrone Claudio , Mancino Raffaele , Cerulli Luciano
Published: August 2013

Purpose

To investigate the intraocular pressure (IOP) reduction with prostaglandin analogs (PGAs)–timolol fixed combinations versus the unfixed combination of the same PGAs and timolol 0.1% in gel-forming carbomer.

Methods

Patients with primary open-angle glaucoma (POAG) receiving for at least 4 weeks the fixed combinations of PGA-timolol, administered once a day in the evening (0.005% latanoprost with 0.5% timolol, 0.004% travoprost with 0.5% timolol, 0.03% bimatoprost with 0.5% timolol) were switched to an unfixed combination of the same PGA (once a day in the evening) with timolol 0.1% in gel-forming carbomer (once a day in the morning) for at least 4 weeks. The primary endpoint was to compare efficacy of fixed vs unfixed combinations in lowering IOP. The effects of both regimens on short-term IOP fluctuations were also assessed.

Results

A total of 32 patients (64 eyes) fulfilled inclusion criteria: 17 patients received latanoprost-timolol fixed combination, 9 travoprost-timolol fixed combination, 6 bimatoprost-timolol fixed combination. For all considered time periods each unfixed combination induced an IOP reduction significantly higher than the corresponding fixed combination (paired t test: p<0.05 in all measurements). The diurnal IOP reduction was significantly higher during the unfixed combinations (p<0.001). Unfixed combinations significantly decreased IOP diurnal fluctuations and increased the percentage of patients with daily IOP fluctuation ≤ 2 mm Hg.

Conclusions

In this pilot study, PGA and timolol seems to be more effective in POAG treatment when administered as unfixed combinations, reducing both IOP and daily fluctuations. The once a day timolol 0.1% gel-forming carbomer may be a valuable option in PGA-timolol unfixed combination regimen.
Persistent plus Disease after Laser in Retinopathy of Prematurity with Tetralogy of Fallot
Authors: Paulus Yannis M. , Moshfeghi Darius M.
Published: August 2013

Purpose

We present a patient with retinopathy of prematurity (ROP) who received panretinal photocoagulation (PRP), but in whom plus disease developed, likely secondary to a complicated cardiovascular history, including DiGeorge syndrome and tetralogy of Fallot.

Methods

Interventional case report with clinical and angiographic correlation.

Results

Our patient had been born at 29 weeks and 2 days gestational age with a birthweight of 940 grams, tetralogy of Fallot, DiGeorge syndrome, and major aortopulmonary collaterals. Type 1 Early Treatment for Retinopathy of Prematurity ROP (zone 2, stage 2 with plus) developed, requiring PRP. Worsening plus disease developed and mild further PRP was performed. Despite this, plus disease persisted.

Conclusions

We report plus disease even after appropriate PRP therapy for ROP. In this case, it is likely the patient's cardiovascular diseases that caused the persistent plus disease. Vascular tortuosity can be due to a number of different systemic disorders, so it is important to consider an infant's systemic conditions in the evaluation of ROP.
Dexamethasone Intravitreal Implant for Idiopathic Retinal Vasculitis, Aneurysms, and Neuroretinitis
Authors: Empeslidis Theodoros , Banerjee Somnath , Vardarinos Athanasios , Konstas Anastasios G.P.
Published: August 2013

Purpose

To present the short-term favorable clinical results with the dexamethasone intravitreal implant in a patient with florid idiopathic retinal vasculitis, aneurysms, and neuroretinitis syndrome (IRVAN).

Methods

A 26-year-old man presented with significant bilateral deterioration of vision due to vitreous hemorrhage and neuroretinitis with a background of vasculitis and neovascularization. The patient was initially treated with high doses of oral steroids (80 mg prednisolone), which were gradually tapered, and also received extensive argon laser photocoagulation in ischemic areas in both eyes. Despite vigorous treatment and an initial positive response to treatment, pars plana vitrectomy was eventually needed to address the recurrent vitreous hemorrhages in the left eye. Consequently, visual acuity improved from 0.1 to 0.2 (Snellen) and there was no relapse of vitreous hemorrhage. Persistent macular edema was noted, however, and it was decided to treat with a dexamethasone 0.7 mg intravitreal implant.

Results

Following the dexamethasone implant OS, visual acuity improved significantly from 0.2 to 0.5 (Snellen), the patient reported much less distortion, and there was marked reduction in central retinal thickness from 467 to 234 microns. The patient remains in remission without any exudation in the macula at 4 months follow-up.

Conclusions

Dexamethasone 0.7 mg intravitreal implant appears to be a safe and effective solution in the treatment of macular edema in patients with IRVAN syndrome and could possibly be a treatment option for other cases of inflammatory induced macular edema.
Red-Free Light for Measurement of Intraocular Pressure Using Goldmann Applanation Tonometer without Fluorescein
Authors: Ghoneim Ehab M.
Published: August 2013

Purpose

To evaluate the use of red-free light for the measurement of intraocular pressure (IOP) using a Goldmann applanation tonometer without fluorescein.

Methods

This cross-sectional study was carried out on 500 eyes in 250 patients attending the Ophthalmology Outpatient Clinic at Suez Canal University Hospital. The IOP was measured using a Goldmann applanation tonometer mounted on a Haag-Streit slit-lamp. The measurements were performed first using red-free light without fluorescein. Then the measurements were repeated with cobalt blue light and topical fluorescein on the same eyes.

Results

The mean IOP was 15.23 ± 3.3 (SD) mm Hg using the red-free light without fluorescein, whereas it was 15.78 ± 3.7 (SD) mm Hg when measured using cobalt blue light after the application of fluorescein to the conjunctival sac. This difference was not statistically significant.

Conclusions

Measurement of IOP with a Goldmann applanationtonometer with red-free light and without the use of fluorescein is simple, saves time, and gives an accurate IOP measurement relative to the traditional measurement technique with cobalt blue light and topical fluorescein.
Riboflavin/UVA Photochemical Therapy for Severe Infectious Keratitis
Authors: Skaat Alon , Zadok David , Goldich Yakov , Varssano David , Berger Yoav , Ezra-Nimni Orit , Avni Isaac , Barequet Irina S.
Published: August 2013

Purpose

To describe the antibacterial activity of treatment with riboflavin and ultraviolet A light (UVA) in cases of severe infectious keratitis.

Methods

A retrospective analysis was performed of an interventional case series in which 6 eyes of 6 patients with severe infectious keratitis, all of whom were refractive to multidrug conventional therapy, were treated with riboflavin/UVA. The procedure was conducted according to the standardized protocol of corneal collagen crosslinking (CXL) for keratoconus. Best spectacle-corrected visual acuity and clinical outcomes were evaluated before and during the follow-up period.

Results

Five of the 6 patients showed rapid reduction in symptoms and decreased infiltrate size after riboflavin/UVA photochemical therapy. Signs of infection and inflammation mostly resolved within 1 to 2 weeks after the treatment. Despite this therapy, one patient continued to deteriorate, and penetrating keratoplasty was performed.

Conclusions

The adjunctive use of riboflavin/UVA photochemical therapy has a positive effect on refractory infectious keratitis. The treatment seems to be safe and effective and should be considered as part of the first-line therapy in severe cases of infectious keratitis.
Ocular Demodicidosis as a Risk Factor of Adult Recurrent Chalazion
Authors: Yam Jason C.S. , Tang Bone S.F. , Chan Tsz-Ming , Cheng Arthur C.K.
Published: August 2013

Purpose:

To report Demodex infestation in adult recurrent chalazion and its clinical response to weekly lid scrub with 50% tea tree oil (TTO) and daily lid scrub with tea tree shampoo.

Methods:

This is a retrospective review of 30 adult patients (48 eyes) who presented with recurrent chalazion within 6 months after conventional treatment. Demodex was detected by random lash sampling and microscopic examination. Patients with confirmed ocular Demodex infestation were treated with weekly lid scrub with 50% TTO and daily lid scrub with tea tree shampoo. The study is limited by the lack of a control group.

Results:

The mean age of patients was 39.1 ± 10.2 years (range 18-69). The mean follow-up of patients is 10.0 ± 3.0 months (range 6-24 months). Among 48 eyes with recurrent chalazion, Demodex mites were found in 35 (72.9%). Recurrent chalazion was found to be associated with ocular demodicidosis (Fisher exact test, p = 0.017). Tea tree oil treatment was given to 31 eyes with recurrent chalazion associated with Demodex infestation. Among the treatment group, all cases except one had no recurrence after the TTO treatment. The success rate of preventing recurrence is 96.8%. Treatment of TTO was found to be associated with preventing recurrence of chalazion associated with Demodex infestation (Fisher exact test, p = 0.002).

Conclusions:

The possibility of demodicidosis should be considered in adults presenting with recurrent chalazia. Tea tree oil eyelid scrubs is an effective treatment in preventing recurrence.
Effect of Axial Length on Retinal Nerve Fiber Layer Thickness in Children
Authors: Öner Veysi , Özgür Gökhan , Türkyilmaz Kemal , Şekeryapan Berrak , Durmuş Mustafa
Published: August 2013

Purpose:

To investigate the effect of axial length on peripapillary retinal nerve fiber layer (RNFL) thickness in myopic, hyperopic, and emmetropic eyes in children by Cirrus HD spectral-domain optical coherence tomography (OCT).

Methods:

Subjects were divided into 3 groups according to their refractive status: myopic (n = 36), emmetropic (n = 30), and hyperopic (n = 28) eyes. The RNFL thickness measurements were taken from the superior, inferior, nasal, and temporal quadrants in the peripapillary region by Cirrus HD OCT. Axial length was also determined for each patient.

Results:

The myopic eyes had thinner average RNFL and RNFLs of temporal, superior, nasal, and inferior quadrants than the hyperopic eyes (p1<0.001, p2 = 0.004, p3 = 0.011, p4 = 0.006, p5 = 0.033, respectively). In addition, average peripapillary RNFL thickness and RNFL thicknesses of all quadrants had significant negative correlations with axial length. On the other hand, after applying modified Littmann formula for correction of magnification effect, the differences among the 3 groups disappeared (all p>0.05).

Conclusions:

We have shown that axial length and accordingly refractive status influenced peripapillary RNFL thickness measurements by Cirrus HD OCT in children. Therefore, to make a correct diagnosis of glaucoma or other optic neuropathies in children, either axial length—induced magnification effect should be corrected by ophthalmologists or the current Cirrus HD OCT database should be revised taking axial length into consideration.
Ophthalmologic Findings in a Pediatric Cochlear Implant Population
Authors: Nikolaos Ziakas , Georgios Psillas , Angeliki Chranioti , Theodoros Lalias , Mattheos Antoniadis , Iosif Vital
Published: August 2013

Purpose:

To report ocular findings in a cohort of children requiring pediatric cochlear implant and to evaluate the usefulness of routine ophthalmologic examination in such children.

Methods:

This was a prospective study of ophthalmologic assessment of 47 consecutive children aged 10 months to 12 years from the cochlear implant program of our hospital.

Results:

All children underwent complete ocular assessment consisting of orthoptic and ophthalmologic examination, including cycloplegic refraction. A total of 18 children (38.3%) had some form of ocular abnormality, with the majority (14 patients, 29.8%) having refractive errors. Hypermetropia was the most common refractive error (21.3%), followed by astigmatism (8.5%). Strabismus was found in 6 patients, with esotropia being the most common type. Other ocular findings included ptosis (1 patient) and epicanthal folds (3 patients). During the follow-up period, 9 children were fitted with glasses, 3 underwent occlusion therapy, 2 underwent strabismus surgery, and 1 underwent ptosis surgery.

Conclusions:

Thorough orthoptic and ophthalmologic examination is useful for ensuring optimal visual function in children undergoing cochlear implantation.
The Removal of Serum Hepcidin by Different Dialysis Membranes
Authors: Kuragano Takahiro , Furuta Minoru , Shimonaka Yasushi , Kida Aritoshi , Yahiro Mana , Otaki Yoshinaga , Hasuike Yukiko , Matsumoto Akihide , Nakanishi Takeshi
Published: August 2013

Purpose

Hepcidin has been suspected to be associated with anemia of chronic disease, which is commonly observed in patients with maintenance hemodialysis (MHD). As almost of hepcidin is bounded to protein, it is essential to clarify which kind of dialysis membrane can remove it efficiently.

Methods

Ex vivo study: 50 mL of whole blood from healthy volunteers were circulated for 2 h in a microcircuit with mini-dialyzers (acrylonitrile-co-methallyl sulfonate (AN69) or polysulfone (PS)) without ultrafiltration. We measured hepcidin-25 levels at 0, 60, and 120 min in the blood samples. In vivo study: Blood samples were taken from 28 MHD patients at the start and end of HD sessions with PS or AN69. We measured serum levels of hepcidin 20, 22, and 25 by liquid chro-matography tandem mass spectrometry, and also measured serum levels of urea nitrogen (UN), P2microglobulin (MG).

Results

Ex vivo study: Although serum hepcidin 25 levels increased after the ex vivo session with PS, they significantly decreased with AN69. In vivo study: The reduction ratio of β2MG by PS was significantly higher than that of AN69. On the other hand, there was no significant difference in the reduction ratio of hepcidin 20, 22, and 25 between PS and AN69.

Conclusions

Both super-flux PS and AN69 similarly removed hepcidin 20 22, and 25. HD with PS might achieve a high removal ratio of hepcidin by enhanced diffusion performance and an increased clearance of small molecule solutes. On the other hand, AN69 might remove hepcidin by adsorption.