bluuebunny/crossref_metadata_2025 huggingface dataset:
Operator Organization for Managing and Integrating New Projects within an Existing Organization
Authors: Durand de Bousingen Jean A.
Published: February 2012

Total Oil Marine, in its role of operator for developments in the North Sea, has handled so far what is described as "Initial Projects", which means large projects where none of the installations existed before and where everything had to be organized and built from scratch.

A typical example is the Frigg transportation system, consisting of a shore terminal, two 32″ pipelines, a manifold compression platform and all the connections with the field production installations. The historical sequence of operations was design, procurement, construction, commissioning and start-up followed by permanent production operations.

In this case, the entire organization required to deal with the problems was built around and with the project. Specific teams were set up, in a sequential mode, to follow the operations pattern until the end when construction teams were completely disbanded to be replaced by production teams.

From then on, the operator organizes himself for permanent production problems, which become the key factor to select people and define the lines of authority.

But new problems arise when additional installations have to be added to the existing ones, whilst production must continue without interruption. Design and construction teams begin to interfere with permanent operations people and have clearly different ideas about their respective roles. Experience indicates that the initial pattern of project organization can no longer be applied without running into a permanent conflict situation.

Total Oil Marine has recognised this difficulty and has tried to introduce within its new projects organization a specific co-ordination and conflict solving role. The aim is to enforce compatibility between design, construction and production operations when they co-exist together with tight schedules. This paper describes how it is being achieved.

It is divided into three parts:-

The specific type of organization that did apply to initial projects. The short-comings of this type of organization and the new roles which are introduced. A New Projects typical organization set up to accommodate simultaneous design, construction and production operations under the operator's control.
The East Midlands Additional Oil Project
Authors: Gair David John , Grist Dennis M. , Mitchell Robert W.
Published: February 2012

The UK East Midlands oil reservoirs are thin estuarine sands of lov; porosity and permeability (1-3 mD) which are normally pressured and produced by pumping. Faulting and the presence of impermeable areas and sand discontinuity has reduced the water-flood recovery efficiency and limits the scope for enhanced recovery although a considerable quantity of oil remains in place.

The paper describes the approach taken to identify potential areas for additional oil recovery and describes tracing work initiated to prove continuity and examine channelling. A critical examination of enhanced recovery techniques in terms of East Midlands conditions is presented and schemes for pilot operations based on viable techniques are presented. These schemes include both multiwell pilots and single well operations.
The potential impacts of climate change on hydropower generation in Mid Wales
Authors: Carless D. , Whitehead P. G.
Published: February 2012

Hydropower is a potential large source of electricity supply in Wales. The Upper River Severn in Mid Wales is a typical stream where a high head hydropower scheme could be developed and the river system at Plynlimon has some of the longest records for weather and flow in Wales. A micro-hydropower potential of 99 kW is demonstrated at Plynlimon and the potential impacts of climate change are simulated to assess the effects on flows and power outputs of such schemes under climate uncertainty. Based on UK Climate Projections 2009 (UKCP09) projections, the impacts of climate change are to significantly decrease both the stream flows and energy production during summer months but to increase flows and power production in the winter, with a net tendency to cancel out over the course of a full year. A methodology for assessing impacts of climate change on hydropower is established, which could be applied more widely to other potential hydropower sites such as lowland rivers or high base flow rivers in other parts of the UK. This will be useful for developers, water companies and environmental agencies to assess hydropower potential, economic viability and environmental impacts of micro-hydropower, under future climate change.
Regional Taiwan rainfall frequency analysis using principal component analysis, self-organizing maps and L-moments
Authors: Chen Lu-Hsien , Hong Yu-Ting
Published: February 2012

The objective of this paper is to propose an approach, which consists of principal component analysis (PCA), self-organizing maps (SOM) and the L-moment method, for improving estimation of desired rainfall quantiles of ungauged sites. Firstly, PCA is applied to obtain the principal components. Then SOM is applied to group the rain gauges into specific clusters and the number of clusters can be objectively decided by visual inspection. Moreover, the L-moment based discordancy and heterogeneity are used to test whether clusters may be acceptable as being homogeneous. After the gauges are grouped into specific clusters, the homogeneous regions are then delineated. Finally, goodness-of-fit measure is used to select the regional probability distributions and the design rainfall quantiles with various return periods for each region can be estimated. The proposed approach is applied to analyze and quantify regional rainfalls in Taiwan. The proposed approach is a robust and efficient way for regional rainfall frequency analysis. Moreover, one can easily assign an ungauged site to a previously defined cluster according to a map of homogeneous regions. Therefore, the proposed approach is expected to be useful for providing the design rainfall quantiles with various return periods at ungauged sites.
Joint climate–hydrology modeling: an impact study for the data-sparse environment of the Volta Basin in West Africa
Authors: Jung Gerlinde , Wagner Sven , Kunstmann Harald
Published: February 2012

The Volta Basin in West Africa is a region sensitive to water shortage. Future climate conditions therefore may put additional stress on the competition for the scarce water resources between industry, agriculture, and households. For an investigation of the sensitivity of the hydrological regime to global climate change in the data-sparse and poorly gauged region of the Volta Basin, joint regional climate–hydrology simulations were performed. MM5 was used as a regional climate model to downscale two time slices of a global ECHAM4 simulation to a resolution of 9 km. These regional climate simulations were used to drive a physically based, distributed hydrological model at 1 km resolution. The performance of the model components and the joint model system was evaluated for different historical periods. Results show that discharge in the Volta Basin reacts highly sensitively to precipitation differences. The pronounced rainfall decrease at the beginning of the rainy season is not transferred to discharge changes. During the rainy season most of the surplus rainfall evaporates due to a strong increase in evaporation as a consequence of higher near-surface air temperatures. The average change signal in precipitation, as well as surface and subsurface hydrology variables, lies in most variables within the range of inter-annual variability, but regionally stronger signals are also observed.
Soil water reserve estimation and vegetation relationships in a Mediterranean sub-humid forested catchment
Authors: Martínez-Fernández J. , Hernández-Santana V.
Published: February 2012

A simple water balance model was used to calculate soil water reserve in a Mediterranean forested catchment. The relationship between soil water reserve and leaf water potential and stem water content was analysed. The usefulness of these variables as plant water status indicators was tested. The analyses were developed with a seven-year-long database (2001–2007) in the case of soil water content and with a four-year long one (2004–2007) for the tree variables. The soil water reserve showed similar types of behaviour for every year, with minimum values at the end of summer (75.2 mm in September 2003) and maxima in winter (204.7 mm in January 2001). The balance model built with precipitation, runoff and ETo simulated the soil moisture content well (r2 = 0.85, p < 0.001). Seasonal variations in the tree variables followed a typical trend, maximum values (−0.18 MPa in June 2007 and 0.654 cm3 cm−3 in May 2004, respectively) being observed at the end of spring, and minimums due to summer drought (−1.5 MPa and 0.520 cm3 cm−3 in August 2005). The relationship was stronger between soil water reserve and stem water content (r2 = 0.85) than with leaf water potential (r2 = 0.67), suggesting stem water content is a more sensitive indicator of water limitation.
System dynamics simulation of soil water resources with data support from the Yucheng Comprehensive Experimental Station, North China
Authors: Zhou Changchun , Luo Yi , Zeppel Melanie
Published: February 2012

System dynamics (SD) is one of the most suitable methods available to simulate and quantify the behaviour of complex systems due to it non-linear, multivariable, information feedback and temporally changing characteristics. This paper has improved on Khan et al.'s established model (see Khan et al. (2009) ‘Analyzing complex behavior of hydrological systems through a system dynamics approach’, Environmental Modeling & Software24, 1363–1372) by adding water production functions for three main crops (winter wheat, summer maize and cotton) based on soil water balance at the field level. Conclusions based on the simulation were as follows. (1) The model could simulate the dynamics of water balance components of winter wheat and summer maize relatively accurately through testing and validation. (2) Two to four irrigations were needed for the water-use requirement for winter wheat and summer maize when irrigation level was 75 mm each time. Cotton did not need to be irrigated except for the addition of 60 mm pre-sowing water. (3) Exploiting groundwater as far as possible and taking measures to reduce soil evaporation and at the same keeping irrigation unchanged was one of the best ways for sustainable utilization of water resources in the upper reaches of the Panzhuang District. (4) Water-use efficiencies were consistent with the regions' measured results showing that the model could simulate the water cycle in the field comparatively accurately.
Simulating streamflow and the effects of projected climate change on the Savage River, Maryland, USA
Authors: Hawkins Timothy W. , Austin Bradley J.
Published: February 2012

The Savage River in western Maryland and its associated reservoir and watershed serves many purposes including recreation, drinking water supply, and auxiliary water supply for Washington DC. Streamflow on the Savage River was modeled using a simple hydrologic model and validated with historical streamflow observations. Future projected climate data were used to drive the model to assess the impact of temperature and precipitation changes on future streamflow. Winter streamflow is projected to increase, while spring, summer, and fall streamflow are projected to decrease. Annual streamflow totals show a slight negative trend over the coming century. Future changes in precipitation are more influential on future streamflow during the winter while temperature may be more important during the summer and fall. On an annual basis, by the year 2098, the impacts of temperature and precipitation will essentially cancel each other out resulting in only a small negative trend in annual streamflow. Increased streamflow during the winter months may not be able to compensate for decreased flow during the remainder of the year which raises concerns about the ability of the reservoir to supply water during future droughts.
Centralized water and wastewater treatment as a greenhouse gas producer in Finland
Authors: Laakso Tuija , Toivikko Saijariina , Vahala Riku
Published: February 2012

Centralized water and wastewater treatment are key components of modern society but, at the same time, sources of greenhouse gas emissions. In this study, we carried out an assessment of the role of centralized water and wastewater treatment as a greenhouse gas producer in Finland, based on the existing literature and a questionnaire study. The aim of the study was to outline the significance of the emissions, as well as to discover what the main sources of the emissions are. The possibility of improving energy efficiency and lowering the emissions were also assessed. Indirect emissions from, for example, the use of chemicals or the manufacture of assets could not be considered when making this preliminary survey. The results of the research indicate that water and wastewater utilities do not produce as much greenhouse gas in Finland as, for instance, the heating of water in private households. We estimated the annual emissions from the centralized water and wastewater sector to be approximately 320,000 t carbon dioxide equivalents. Emissions could be reduced through, for example, shifting to energy-efficient sludge treatment, such as anaerobic methods. We estimated that gaseous emissions resulting from wastewater treatment, wastewater sludge treatment, the discharge of treated effluent and sludge disposal in landfills form approximately 50% of total emissions.
Will climate change affect the electricity production sector? A European study
Authors: Flörke M. , Bärlund I. , Kynast E.
Published: February 2012

Climate change and increasing electricity production affect future freshwater requirements for thermoelectric power plants in Europe. This paper explores the reasons and shows ‘hot spots’ for further analysis. A scenario and simulation approach was selected to estimate water availability and water uses in Europe up to 2050. Depending on the scenario, water withdrawals in thermal electricity production would increase by 64% or decrease by 92% between 2005 and 2050. At the same time, average summer water availability is expected to decrease because of climate change in southern and south-eastern parts of Europe. In these regions in particular, hot spots were identified where water is scarce and where growing water demand is likely to exacerbate water stress which may cause economic losses. Hot spots identified in the Economy First scenario indicate increasing competition for freshwater resources for the thermal electricity production sector. Increasing efficiency and improved awareness as assumed in the Sustainability Eventually scenario can reduce these hot spots by 90%.
Energy efficiency in the European water industry: learning from best practices
Authors: Frijns J. , Middleton R. , Uijterlinde C. , Wheale G.
Published: February 2012

Energy costs and climate change challenges the water industry to improve their energy efficiency. The number of examples of energy measures in water production and treatment is growing rapidly. In this paper, best practices of energy efficiency from the European water industry are presented with the objective of learning from each other. The best practices are collected within the framework of the Global Water Research Coalition's attempt to devise a global compendium ‘Best practices in the energy efficient design and operation of water industry assets’. The case studies in the compendium show significant energy savings in all parts of the water cycle. Examples with potential include the improved operational set up of pumping design, on line aeration control, and energy-efficient bubble aerators and sludge belt thickeners. Next to optimising energy efficiency across the water cycle, there are also opportunities for energy generation. Promising practices include biogas production from sludge (co)digestion and hydraulic energy generation from micro-turbines.
Experiences and lessons learned from practical implementation of a software-supported Water Safety Plan (WSP) approach
Authors: Mayr Ernest , Lukas Aditya , Aichlseder Wolfgang , Perfler Reinhard
Published: February 2012

The Water Safety Plan (WSP) is considered the preferred approach to ensure drinking water safety by the World Health Organization (WHO). This approach ideally requires extensive scientific and technical input from a multidisciplinary team of experts. However, in small- and medium-sized municipalities in Austria, financial and personnel resources are usually of very limited availability. Therefore, a spreadsheet based WSP tool was designed to facilitate the implementation of the WSP approach at these small supply units. The WSP tool comprises the relevant national Austrian guidelines, which include the key components of the WSP by the WHO. The tool provides an overview of the required steps, explains how to carry out each step and guides the user through the three key components: system and hazards assessment, control measures and operational monitoring, and management. The practical application of the WSP tool was tested at 12 water utilities over a period of three months. After this period, the tool was improved based on collected feedback from the water utilities.
Success or failure: demonstrating the effectiveness of a Water Safety Plan
Authors: Mudaliar M. M.
Published: February 2012

The Water Safety Plan (WSP) concept has become a globally recognised and accepted approach to drinking water supply management and operation. Many countries around the world are adopting this proactive, risk-based model for ensuring consistent confidence in drinking water safety, accessibility and affordability. While it is widely accepted that the WSP concept is an appropriate tool for ensuring drinking-water supply efficiency, the process for gathering the required evidence to demonstrate this continues to be rather vague. The problem may lie fundamentally in the way WSPs are developed and implemented. This paper discusses the need for establishing performance targets, identifying key performance indicators and monitoring these to build a body of evidence that would be instrumental in demonstrating whether WSPs are effective or not.
Jordan water demand management study: on behalf of the Jordanian Ministry of Water and Irrigation in cooperation with the French Development Agency (AFD)
Authors: Wolff Heinz Peter , Al-Karablieh Emad , Al-Assa'd Tamer , Subah Ali , Salman Amer Z.
Published: February 2012

The Jordanian National Water Master Plan (2004) stipulates water demand management (WDM) as one of the central strategies in achieving a more efficient and cost-effective water use. A new study under the funding mechanism of a regional program, led by the French Development Agency, reviewed and analyzed the situation in different sectors of water consumption, updated information on water values and applied economic assessment approaches to selected cases of ongoing WDM activities. The findings provide the basis for analysis and consistency checks of scenarios, which were developed in workshops with experts from the Ministry of Water and Irrigation, the Water Authority of Jordan, the Jordan Valley Water Authority and the Water and Environmental Research and Study Center of the University of Jordan. A core outcome of this study will be a policy brief for wider dissemination to stakeholders and decision makers in Jordan and other Mediterranean countries.
Effect of low power ultrasound on aerobic/anoxic digestion of activated sludge
Authors: Li Zheng , Shuiyu Sun , Yanbin Xu , Weiting Yao , Wenjin Tong
Published: February 2012

The effect of low power ultrasound on aerobic/anoxic digestion of activated sludge was investigated. First, dehydrogenate activity (DHA) and special oxygen uptake rate (SOUR) were detected to indicate the change of biological activity of sludge induced by ultrasound. Single-factor experiments showed that when the ultrasonic frequency was 28 kHz, the optimal ultrasonic density and exposure time were 0.15 W/mL and 10 min, respectively. Through orthogonal tests, the optimal ultrasonic parameters for aerobic/anoxic digestion were found to be a ultrasonic density of 0.15 W/mL, ultrasonic exposure time of 10 min and interval time of 12 h. The aerobic/anoxic digestion was improved by ultrasonic pretreatment, the VSS reduction at the optimal conditions was increased by 35.73%, compared with the control. It can be concluded that low power ultrasonic pretreatment is a valid method for improving aerobic/anoxic biodegradability of activated sludge.
The denitration pathway of p-nitrophenol in the hydrogen peroxide catalytic oxidation with an FeIII-resin catalyst
Authors: Liou Rey-May
Published: February 2012

The liquid-phase hydrogen peroxide catalytic oxidation of p-nitrophenol was performed with an FeIII-resin catalyst. The conversion and mineralization of p-nitrophenol was effectively achieved at mild reaction conditions with the FeIII-resin catalyst. It was found that the oxidant concentration, pH, and temperature dominated the degradation rate of p-nitrophenol. The denitration pathway of p-nitrophenol was proposed, in which the concentration of H2O2 and temperature showed strong influence on the conversion of nitrite to nitrate. To study the factors influencing the denitration of p-nitrophenol, a comparable kinetic study was attempted to know the possible denitration pathway of p-nitrophenol. The results of this investigation indicated that denitration was the possible step occurring with the decomposition of p-nitrophenol.
Plant algae method for arsenic removal from arsenic contaminated groundwater
Authors: de la Paix Mupenzi Jean , Lanhai Li , de Dieu Habumugisha Jean , John Maina Nyongesah
Published: February 2012

Field studies were carried out in Urumqi River Basin in Northwest China. The study focused on experimentation on a plant algae method that was tested by taking various water chemistries into consideration. The results from a greenhouse experiment evaluated for four doses of P (0, 100, 200, and 300 μmol/L) using two ferns (30 and 60 day old) on 15 L of contaminated groundwater per plant revealed that the biomass of 30-day old ferns gained was higher than 60-day fern. As solution-P increased from 0 to 450 μmol/L, Phosphorus concentration in the fronds increased from 1.9 to 3.9 mg/kg and 1.95 to 4.0 mg/kg for 30-d and 60-d ferns respectively. This study showed that the plant algae method may be a good solution to maximize arsenic uptake in the short term under normal climatic conditions.
Analysis of the contributions of pollution to industrial discharge categories in Korea using the Modified Toxic Weighting Factor
Authors: Kim Kyeong-Jin , Yeom Ick-Tae
Published: February 2012

In 2007, 45,163 domestic industrial direct/indirect discharge sources were registered in Korea, which have been categorized into 82 divisions based on the characteristics of their products, raw materials and wastewaters. The purpose of this study was to set priorities using a risk assessment of pollutants toxic weighting for each industrial category with respect to pollution prevention and control. This study developed the upgraded Modified Toxic Weighting Factors (MTWFs) rather than the Toxic Weighting Factors (TWFs) suggested by the United States Environmental Protection Agency (USEPA) with respect to domestic environmental regulations, and the assessment of existing databases of domestic industrial wastewater characteristics for the 82 categorized industries in Korea. Finally, priority of industrial categories and pollutants were established to determine the target industries and pollutants requiring controls. High contributing categories in order of their pollution loads were pulp, paper and paper products manufacturing, dyeing and processing facilities, etc. The top 10 industrial category loads accounted for 76.0% of the total effluent equivalent kilograms of pollution. High contributing categories, in order of their toxic level were synthetic resins and other plastics manufacturing, leather and fur processing and manufacturing.
The effect of intermittent operation on a wind-powered membrane system for brackish water desalination
Authors: Park G. L. , Schäfer A. I. , Richards B. S.
Published: February 2012

Renewable energy powered membrane systems that are directly-connected must take account of both the inherent fluctuations and the intermittency of the energy resource. In order to determine the effect of intermittent operation, a membrane system was tested with variables of (i) amplitude from 60 to 300 W and (ii) length of time with no power from 0.5 to 3 min. This was performed over one hour periods with six on/off cycles to simulate the system operating under intermittent operation for short periods of time when directly-connected to a small wind turbine. The setup used a Filmtec BW30-4040 brackish water reverse osmosis membrane with feed waters of 2,750 mg/L and 5,500 mg/L NaCl. The results showed that the membrane system produced potable water under the majority of intermittency experiments performed. There was a relatively large increase in the average salt concentration of the permeate, especially when the system was off for shorter periods of time (0.5–1 min). Longer periods of no power (1–3 min) did not have as significant an effect on the average water quality. This is important when the need for energy buffering or short term storage is considered for these systems as it shows the potential for improving the overall flux and water quality using temporary energy storage.
Determining potential indicators of Cryptosporidium oocysts throughout the wastewater treatment process
Authors: Cheng H.-W. A. , Broaders M. A. , Lucy F. E. , Mastitsky S. E. , Graczyk T. K.
Published: February 2012

Most research on wastewater treatment efficiency compliance focuses on physicochemical and microbial indicators; however, very little emphasis has been placed so far on determining suitable indicator organisms to predict the discharge level of pathogens from treatment plants. In this study, raw wastewater, activated sludge, and the resulting final effluents and biosolids in four municipal wastewater treatment plants (WWTPs A, B, C and D) were seasonally investigated for human-virulent water-borne pathogens Cryptosporidium parvum/hominis and Giardia duodenalis, and microsporidia (e.g. Encephalitozoon hellem, E. intestinalis, and Enterocytozoon bieneusi) between 2008 and 2009. A suite of potential microbial indicators for human-virulent protozoa and microsporidia was also determined. A combination of multiple fluorescent in situ hybridization and immunofluorescent antibody assays were applied to detect Cryptosporidium oocysts, Giardia cysts, and microsporidian spores. Escherichia coli, enterococci and Clostridium perfringens spores were cultivated in selective media. Positive correlations were found between the abundance of enterococci and E. coli and abundance of Cryptosporidium oocysts (rs > 0.47, p < 0.01) and Giardia cysts (rs > 0.44, p < 0.01) at WWTPs A–D. Cryptosporidium perfringens spores were positively correlated to Cryptosporidium oocysts (rs = 0.40, p < 0.01) and Giardia cysts (rs = 0.46, p < 0.01). There was a strong positive correlation between abundance of Giardia cysts and that of Cryptosporidium oocysts (rs > 0.89, p < 0.01). To sum up, a suite of faecal indicator bacteria can be used as indicators for the presence of Cryptosporidium oocysts and Giardia cysts in these activated-sludge systems (WWTPs A, B and C). Overall, Giardia duodenalis was noted to be the best Cryptosporidium indicator for human health in the community-based influent wastewater and throughout the treatment process.
Economic feasibility study for new technological alternatives in wastewater treatment processes: a review
Authors: Molinos-Senante María , Hernández-Sancho Francesc , Sala-Garrido Ramón
Published: February 2012

The concept of sustainability involves the integration of economic, environmental, and social aspects and this also applies in the field of wastewater treatment. Economic feasibility studies are a key tool for selecting the most appropriate option from a set of technological proposals. Moreover, these studies are needed to assess the viability of transferring new technologies from pilot-scale to full-scale. In traditional economic feasibility studies, the benefits that have no market price, such as environmental benefits, are not considered and are therefore underestimated. To overcome this limitation, we propose a new methodology to assess the economic viability of wastewater treatment technologies that considers internal and external impacts. The estimation of the costs is based on the use of cost functions. To quantify the environmental benefits from wastewater treatment, the distance function methodology is proposed to estimate the shadow price of each pollutant removed in the wastewater treatment. The application of this methodological approach by decision makers enables the calculation of the true costs and benefits associated with each alternative technology. The proposed methodology is presented as a useful tool to support decision making.
Characterizing natural dissolved organic matter in a freshly submerged catchment (Three Gorges Dam, China) using UV absorption, fluorescence spectroscopy and PARAFAC
Authors: Chen Hao , Zheng Binghui
Published: February 2012

This study applied parallel factor analysis (PARAFAC) to fluorescence excitation–emission matrices (EEMs) of natural water samples in a freshly submerged catchment in the upper reach of Three Gorges Dam (China). Two fluorescent natural dissolved organic matter (NDOM) components (humic/fulvic-like) were uncovered and were positively correlated with selected water quality parameters, i.e. dissolved oxygen concentration, dissolved organic carbon concentration, dissolved Kjeldahl nitrogen concentration and total (dissolved plus particulate) phosphorus concentration, respectively. To other water quality parameters (i.e. total nitrogen, particulate nitrogen, particulate phosphorus, dissolved phosphorus, dissolved nitrate, pH, and chemical oxygen demand), either the two components did not show any correlation or only one component showed correlation. In particular, particulate N correlated significantly to the fulvic acid, but not to the humic acid. Meanwhile, two conventional spectroscopic indices i.e. specific UV absorbance at 254 nm (SUVA254) and fluorescence index (FI) indicated that the whole NDOM in the waters were low in aromaticity and predominantly derived from aquatic microbial processes. Given together, it concludes that N and P did not function equally in the NDOM production, and the two components were not derived from the same microbial processes. The EEMs-PARAFAC has proven to be of potential as an effective tool in investigation of the interlink between NDOM and nutrients which may be utilized as an indicator of water environment.
Isolation of a phenol-utilizing marine bacterium from Durban Harbour (South Africa) and its preliminary characterization as Marinobacter sp. KM2
Authors: Moxley Karis , Schmidt Stefan
Published: February 2012

Many aromatic hydrocarbons assigned to the so-called high production volume chemicals (HPVCs) are frequently encountered constituents of wastewaters that end up in the sea. Although the pollutant-degrading capabilities of freshwater bacteria are well known, the catabolism of pollutants by marine bacteria has received limited attention. A marine bacterium with the ability to aerobically utilize phenol – an HPVC and common aromatic pollutant – as its sole source of carbon and energy, was isolated from water samples from Durban Harbour, South Africa. The isolate, designated strain KM2, was assigned to the genus Marinobacter based on a variety of phenotypic properties and by analysis of the 16S rRNA gene sequence. The isolate displays an absolute growth requirement for NaCl which cannot be offset by replacement of NaCl with other salts. In addition to 4-methylphenol and 3,4-dimethylphenol, it utilizes a range of aliphatic hydrocarbons such as butan-1-ol and hexadecane under aerobic conditions. The transient formation of an intermediate exhibiting the UV–Vis spectral characteristics for 2-hydroxymuconic semialdehyde in cultures growing on phenol suggests that the isolate catabolizes this compound via the meta cleavage pathway. These results indicate that members of the genus Marinobacter might participate in the elimination of aromatic pollutants in South African marine environments.
Effect of low dosages of powdered activated carbon on membrane bioreactor performance
Authors: Remy Maxime , Temmink Hardy , Rulkens Wim
Published: February 2012

Previous research has demonstrated that powdered activated carbon (PAC), when applied at very low dosages and long SRTs, reduces membrane fouling in membrane bioreactors (MBRs). This effect was related to the formation of stronger sludge flocs, which are less sensitive to shear. In this contribution the long-term effect of PAC addition was studied by running two parallel MBRs on sewage. To one of these, PAC was dosed and a lower fouling tendency of the sludge was verified, with a 70% longer sustainable filtration time. Low PAC dosages showed additional advantages with regard to oxygen transfer and dewaterability, which may provide savings on operational costs.
A Controlled Study of Depression among Attendees of an Oncology Clinic in West Africa
Authors: Olagunju Andrew T. , Aina Olatunji F.
Published: February 2012

Objective:

Depression is commonly encountered among cancer patients and has been linked with grave consequences if not promptly treated. This study was set to determine the prevalence of depression in cancer patients.

Method:

The samples were recruited using systematic random sampling and made up of 200 cancer patients and 200 age and sex matched controls that consented and met the inclusion criteria. The instruments used included: Socio-demographic and clinical profile questionnaire, Centre for Epidemiological Studies Depression Scale Revised (CES-DR), and the Schedule for Clinical Assessment in Neuropsychiatry (SCAN). The instruments were administered by the researchers on the subjects and controls, and data obtained were analyzed using SPSS-15.

Results:

A larger proportion of cancer patients compared to controls had depressive symptomatology (CES-DR score of 16 and above) made up of 98 (49.0%) cancer patients compared to 40 (20.0%) controls, and the difference was statistically significant, p = < 0.001. Seventy-four (18.5%) subjects from the two groups had depressive disorder using SCAN. The prevalence of depression in cancer subjects was 27.5% with 9.5% in controls and the difference was statistically significant with p = < 0.001. A substantial proportion of cancer patients with depression, 36 (65.5%, n = 55), had moderate depression, 15 (27.3%, n = 55) were mildly depressed, and 7.2% ( n = 55) had severe depression.

Conclusion:

A significant proportion of cancer patients had depression compared with the controls with acute medical conditions. Prompt identification and treatment of cancer, mental disorders like depression should be integrated into cancer care in this part of the world.
Why John Wasn't Healed by Prayer: Perspectives across Disciplines
Authors: Blazer Dan G. , Cohen Harvey Jay , George Linda K. , Koenig Harold G. , Verhey Allen
Published: February 2012

Patients and family members often turn to prayer in response to serious, life-threatening illness. Prayer for a miraculous cure is often the request. While prayer can keep hope alive, it may also promote unrealistic expectations that fuel demands for life-preserving technology in medically futile situations. Furthermore, if prayer does not achieve the desired results, then disappointment and disillusionment may follow and make the coping process even more difficult. We present here a case of a seriously ill man whose family and faith community prayed for his healing. John, however, was not healed. A medical internist, two psychiatrists, a sociologist, and a theologian discuss their perspectives on the apparent failure of prayer to heal John. This cross-disciplinary discussion reveals insights that we believe physicians can use when confronting such issues with patients.
Posttraumatic Stress Disorder following Myocardial Infarction: Personality, Coping, and Trauma Exposure Characteristics
Authors: Chung Man Cheung , Dennis Ian , Berger Zoë , Jones Rupert , Rudd Hannah
Published: February 2012

Objective:

This study aimed to investigate the interrelationship between trauma exposure characteristics of myocardial infarction (MI), MI patients' personality traits, coping strategies, post-MI PTSD, and general psychological distress.

Method:

One hundred and twenty MI patients were recruited from two general practices. The MI patients were interviewed using a MI experience questionnaire and completed the Posttraumatic Stress Diagnostic Scale (PDS), the General Health Questionnaire-28 (GHQ-28), the NEO-Five Factor Inventory (NEO-FFI), and the COPE Scale.

Results:

Neuroticism was directly associated with post-MI PTSD and general psychological distress, while agreeableness did not link to the outcomes directly. Neuroticism influenced MI exposure characteristics which in turn influenced PTSD. Agreeableness affected PTSD and general psychological distress through MI exposure characteristics. Neuroticism influenced problem-focused coping which in turn affected general psychological distress. Agreeableness influenced problem-focused coping which in turn affected PTSD and general psychological distress.

Conclusions:

Patients developed PTSD and general psychological distress following MI. Neurotic and antagonistic personality traits combined with patients' subjective experiences of MI and usage of problem-focused coping influenced the severity of outcomes.
Does Having a Chronic Physical Condition Affect the Likelihood of Treatment Seeking for a Mental Health Problem and Does This Vary by Ethnicity?
Authors: Scott K. M. , Kokaua J. , Baxter J.
Published: February 2012

Objective:

The comorbidity of mental disorders with chronic physical conditions is known to have important clinical consequences, but it is not known whether mental-physical comorbidity influences mental health treatment seeking. This study investigates whether the presence of a chronic physical condition influences the likelihood of seeking treatment for a mental health problem, and whether that varies among ethnic subgroups in New Zealand.

Methods:

Analyses were based on a subsample ( n = 7,435) of The New Zealand Mental Health Survey, a nationally representative household survey of adults (response rate 73.3%). Ethnic subgroups (Maori and Pacific peoples) were oversampled. DSM-IV mental disorders were measured face-to-face with the Composite International Diagnostic Interview (CIDI 3.0). Ascertainment of chronic physical conditions was via self-report.

Results:

In the general population, having a chronic medical condition increased the likelihood of seeking mental health treatment from a general practitioner (OR: 1.58), as did having a chronic pain condition (OR: 2.03). Comorbid chronic medical conditions increased the likelihood of seeking mental health treatment most strongly among Pacific peoples (ORs: 2.86–4.23), despite their being less likely (relative to other ethnic groups) to seek mental health treatment in the absence of physical condition comorbidity.

Conclusion:

In this first investigation of this topic, this study finds that chronic physical condition comorbidity increases the likelihood of seeking treatment for mental health problems. This provides reassurance to clinicians and health service planners that the difficult clinical problem of mental-physical comorbidity is not further compounded by the comorbidity itself constituting a barrier to mental health treatment seeking.
Kidney Volume and Functional Outcomes in Autosomal Dominant Polycystic Kidney Disease
Authors: Chapman Arlene B. , Bost James E. , Torres Vicente E. , Guay-Woodford Lisa , Bae Kyongtae Ty , Landsittel Douglas , Li Jie , King Bernard F. , Martin Diego , Wetzel Louis H. , Lockhart Mark E. , Harris Peter C. , Moxey-Mims Marva , Flessner Mike , Bennett William M. , Grantham Jared J.
Published: February 2012

Background and objectives

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by increased total kidney volume (TKV) and renal failure. This study aimed to determine if height-adjusted TKV (htTKV) predicts the onset of renal insufficiency.

Design, setting, participants, & measurements

This prospective, observational, longitudinal, multicenter study included 241 adults with ADPKD and preserved renal function. Magnetic resonance imaging and iothalamate clearance were used to measure htTKV and GFR, respectively. The association between baseline htTKV and the attainment of stage 3 CKD (GFR <60 ml/min per 1.73 m2) during follow-up was determined.

Results

After a mean follow-up of 7.9 years, stage 3 CKD was attained in 30.7% of the enrollees. Using baseline htTKV, negative correlations with GFR increased from −0.22 at baseline to −0.65 at year 8. In multivariable analysis, a baseline htTKV increase of 100 cc/m significantly predicted the development of CKD within 8 years with an odds ratio of 1.48 (95% confidence interval: 1.29, 1.70). In receiver operator characteristic curve analysis, baseline htTKV of 600 cc/m most accurately defined the risk of developing stage 3 CKD within 8 years with an area under the curve of 0.84 (95% confidence interval: 0.79, 0.90). htTKV was a better predictor than baseline age, serum creatinine, BUN, urinary albumin, or monocyte chemotactic protein-1 excretion (P<0.05).

Conclusions

Baseline htTKV ≥600 cc/m predicted the risk of developing renal insufficiency in ADPKD patients at high risk for renal disease progression within 8 years of follow-up, qualifying htTKV as a prognostic biomarker in ADPKD.
MicroRNAs in Patients on Chronic Hemodialysis (MINOS Study)
Authors: Emilian Cristina , Goretti Emeline , Prospert Fernand , Pouthier Dominique , Duhoux Pierre , Gilson Georges , Devaux Yvan , Wagner Daniel R.
Published: February 2012

Background and objectives

Diagnosis of acute myocardial injury with biomarkers is difficult in patients with advanced renal failure. Circulating microRNAs are promising new biomarkers of myocardial injury. It is unknown whether levels of microRNAs are affected in patients undergoing hemodialysis.

Design, setting, participants, & measurements

High-sensitivity cardiac troponin T (hsTnT) and cardiac-enriched miR-499 were measured in 41 patients with ESRD undergoing hemodialysis and 41 controls.

Results

Levels of hsTnT and miR-499 were highly elevated in patients with ESRD compared with controls (>80-fold increase;P<0.001). Among patients with ESRD, 98% had positive hsTnT levels and 46% had positive miR-499 levels. Levels of troponins were not affected by hemodialysis. However, miR-499 levels were decreased after hemodialysis (6.5-fold decrease;P=0.002).

Conclusions

Both miR-499 and troponins are elevated in patients with advanced renal failure. However, whereas levels of troponins are unaffected by hemodialysis, this is not the case for miR-499. Therefore, these observations mitigate the potential of miR-499 as a marker of myocardial injury in patients with ESRD.
Use of Secondary Prevention Medications among Adults with Reduced Kidney Function
Authors: Chang Tara I. , Gao Liyan , Brown Todd M. , Safford Monika M. , Judd Suzanne E. , McClellan William M. , Limdi Nita A. , Muntner Paul , Winkelmayer Wolfgang C.
Published: February 2012

Background and objectives

Persons with kidney disease often have cardiovascular disease, but they are less likely to use recommended medications for secondary prevention. The hypothesis was that participants with reduced estimated GFR have lower use of medications recommended for secondary prevention of cardiovascular events (antiplatelet agents, angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, β-blockers, and statins) and lower medication adherence than participants with preserved estimated GFR.

Design, setting, participants, & measurements

In this cross-sectional analysis, we analyzed data from 6913 participants in the Reasons for Geographic and Racial Differences in Stroke study with a history of cardiovascular disease. Medication use was ascertained by an in-home pill bottle review. Medication adherence was assessed using a validated four-item scale.

Results

Among participants with a history of cardiovascular disease, 59.8% used antiplatelet agents, 49.9% used angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, 41.6% used β-blockers, and 53.0% used statins. Compared with the referent group (estimated GFR ≥60 ml/min per 1.73 m2), participants with estimated GFR <45 ml/min per 1.73 m2 were more likely to use angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers (adjusted prevalence ratio=1.14, 95% confidence interval=1.06–1.23), β-blockers (adjusted prevalence ratio=1.20, 95% confidence interval=1.09–1.32), and statins (adjusted prevalence ratio=1.10, 95% confidence interval=1.01–1.19). Antiplatelet agent use did not differ by estimated GFR category; 30% of participants reported medication nonadherence across all categories of estimated GFR.

Conclusions

Among participants with a history of cardiovascular disease, mild to moderate reductions in estimated GFR were associated with similar and even more frequent use of medications for secondary prevention compared with participants with preserved estimated GFR. Overall medication use and adherence were suboptimal.
Use of an Automated Decision Support Tool Optimizes Clinicians’ Ability to Interpret and Appropriately Respond to Structured Self-Monitoring of Blood Glucose Data
Authors: Rodbard Helena W. , Schnell Oliver , Unger Jeffrey , Rees Christen , Amstutz Linda , Parkin Christopher G. , Jelsovsky Zhihong , Wegmann Nathan , Axel-Schweitzer Matthias , Wagner Robin S.
Published: February 2012

OBJECTIVE

We evaluated the impact of an automated decision support tool (DST) on clinicians’ ability to identify glycemic abnormalities in structured self-monitoring of blood glucose (SMBG) data and then make appropriate therapeutic changes based on the glycemic patterns observed.

RESEARCH DESIGN AND METHODS

In this prospective, randomized, controlled, multicenter study, 288 clinicians (39.6% family practice physicians, 37.9% general internal medicine physicians, and 22.6% nurse practitioners) were randomized to structured SMBG alone (STG; n = 72); structured SMBG with DST (DST; n = 72); structured SMBG with an educational DVD (DVD; n = 72); and structured SMBG with DST and the educational DVD (DST+DVD; n = 72). Clinicians analyzed 30 patient cases (type 2 diabetes), identified the primary abnormality, and selected the most appropriate therapy.

RESULTS

A total of 222 clinicians completed all 30 patient cases with no major protocol deviations. Significantly more DST, DVD, and DST+DVD clinicians correctly identified the glycemic abnormality and selected the most appropriate therapeutic option compared with STG clinicians: 49, 51, and 55%, respectively, vs. 33% (all P < 0.0001) with no significant differences among DST, DVD, and DST+DVD clinicians.

CONCLUSIONS

Use of structured SMBG, combined with the DST, the educational DVD, or both, enhances clinicians’ ability to correctly identify significant glycemic patterns and make appropriate therapeutic decisions to address those patterns. Structured testing interventions using either the educational DVD or the DST are equally effective in improving data interpretation and utilization. The DST provides a viable alternative when comprehensive education is not feasible, and it may be integrated into medical practices with minimal training.