Costs and Effects of Abdominal versus Laparoscopic Hysterectomy: Systematic Review of Controlled Trials

Objective: Comparative evaluation of costs and effects of laparoscopic hysterectomy (LH) and abdominal hysterectomy (AH). Data sources: Controlled trials from Cochrane Central register of controlled trials, Medline, Embase and prospective trial registers. Selection of studies: Twelve (randomized) controlled studies including the search terms costs, laparoscopy, laparotomy and hysterectomy were identified. Methods: The type of cost analysis, perspective of cost analyses and separate cost components were assessed. The direct and indirect costs were extracted from the original studies. For the cost estimation, hospital stay and procedure costs were selected as most important cost drivers. As main outcome the major complication rate was taken. Findings: Analysis was performed on 2226 patients, of which 1013 (45.5%) in the LH group and 1213 (54.5%) in the AH group. Five studies scored >= 10 points (out of 19) for methodological quality. The reported total direct costs in the LH group ($63,997) were 6.1$60,114). The reported total indirect costs of the LH group ($1,609) were half of the total indirect in the AH group ($3,139). The estimated mean major complication rate in the LH group (14.3%) was lower than in the AH group (15.9%). The estimated total costs in the LH group were $3,884 versus$3,312 in the AH group. The incremental costs for reducing one patient with major complication(s) in the LH group compared to the AH group was $35,750. Conclusions: The shorter hospital stay in the LH group compensates for the increased procedure costs, with less morbidity. LH points in the direction of cost effectiveness, however further research is warranted with a broader costs perspective including long term effects as societal benefit, quality of life and survival

Evaluation of Zeolite Adsorption Properties for Cu(II) Removal from Acidic Aqueous Solutions in Fixed-Bed Column System

The development of human society after 18th century is associated with metals. Technology of extraction and processing of heavy metals is essential for many areas of industry. Naturally, the extraction, processing and cleaning of impurities give the metals not only a new form, but also cause their intensive distribution in the environment, which represents a huge threat. Countries of the middle Europe, where extraction of mineral resources takes place a long period, have to solve the problems of mine wastewater. Finding of the new and cheap ways of these wastewater treatment can increase the quality of the environment in the affected areas. Sorption techniques belong to an effective and cost acceptable methods for remove of heavy metals from aqueous environment. The presented paper describes the adsorption behavior of Slovak natural zeolite in fixed-bed column system. In order to determine its applicability for mine drainage treatment, copper removal from model sulfuric acid solutions (pH 4) was studied

Using of zeolite for copper and zinc removal under acidic conditions

The adsorption properties of natural zeolite (clinoptilolite) has been studied in order to determine its applicability for copper and zinc removal in acid mine drainage treatment process. For purpose of these experiments the determination of the sorption equilibrium and removal efficiencies were performed under batch conditions using single and dual-component solutions. The experiments were carried out under acidic conditions (pH approx. 4). In general, the obtained results from kinetic experiments showed rapid decrease of the metal concentration during the first 10 min, corresponding to ~80% total removal of ions from both single and dualcomponent solutions. This initial rapid period was followed by a further slow drop in metals concentration caused by ion-exchange in deeper structure of zeolite.Preliminary tests on the real samples of acid mine drainage from Smolnik mine, Slovakia, showed that natural zeolite has a potential as an alternative low cost adsorptive material for acid mine drainage treatment

Testing of various sorbents for copper sorption from acidic solutions

Heavy metals, including copper, are a serious environmental problem today. As an essential part of acid mine drainage they cause degradation of surface and subsurface water quality, including drinking water. Significant character of acid mine drainage is low value of pH, as a result of hydrogen cations releasing into aqueous environment during the process of pyrite oxidation and high concentration of heavy metals. Sorption techniques are widely used to remove heavy metal ions from large volumes of aqueous solutions. The fact of low pH must be taken in consideration because it has a relevant impact on the behavior of the sorbent during the sorption process.In order to study the optimal parameters of the sorption process of Cu(II) from acid mine drainage (pH=3–4), two sorbents under model conditions in solutions with pH of 4 were studied. For this purpose low cost natural sorbents turf brush PEATSORB and natural zeolite were selected. Different contact time and various initial concentrations of ions were tested as variables. The properties of the tested sorbents were compared from the point of view of their efficiency and sorption capacity. The impact of sorption on the pH change in solution was also studied

Study of sulphate ions removal from acidic waters using ion exchange resin

Acid Mine Drainage (AMD) is the most common pollution related to mining. It consists of an aqueous solution containing high metals and sulphate concentration, which impact surface and groundwater and lead to serious environmental problems. Low pH and high concentrations of heavy metals and sulphates are limiting for many various treatment technologies in these acidic waters. Ion - exchange is a very powerful technology where one or more undesirable contaminants are removed from water by exchange with another non-objectionable or less objectionable substance. Many of materials for the ion - exchange treatment is available in a variety forms and have widely differing chemical and physical properties. The paper deals with study of ion - exchange process under static and dynamic conditions for sulphate removal from acidic waters using ion - exchange resin with the aim to apply the results for treatment of acid mine drainage. Two types of experiments were performed under static and dynamic conditions. The efficiency of AMBERLITE MB20 resin for SO4 2- removal from model solution H2SO4 under static conditions decreases from 86.6 % for concentration 100 mg/L to efficiency 66.9 % for concertation 1000 mg/L. The efficiency for sulphate removal from AMD was only 41%. The study also presents three experiments under dynamic conditions, one with new ion - exchange resin a two experiments with its regenerated form. It was find that ion-exchange capacity decreases numbers of regeneration steps

Evaluation of Zeolite Adsorption Properties for Cu(II) Removal from Acidic Aqueous Solutions in Fixed-Bed Column System

The development of human society after 18th century is associated with metals. Technology of extraction and processing of heavy metals is essential for many areas of industry. Naturally, the extraction, processing and cleaning of impurities give the metals not only a new form, but also cause their intensive distribution in the environment, which represents a huge threat. Countries of the middle Europe, where extraction of mineral resources takes place a long period, have to solve the problems of mine wastewater. Finding of the new and cheap ways of these wastewater treatment can increase the quality of the environment in the affected areas. Sorption techniques belong to an effective and cost acceptable methods for remove of heavy metals from aqueous environment. The presented paper describes the adsorption behavior of Slovak natural zeolite in fixed-bed column system. In order to determine its applicability for mine drainage treatment, copper removal from model sulfuric acid solutions (pH 4) was studied

The removal of sulphate ions from model solutions and their influence on ion exchange resins

There is a growing tendency for industries around the globe to diminish the contents of pollutants in industrial wastewaters to an acceptable level. Conventional methods are unfavourable and economically unacceptable, especially for large volumes of wastewaters with a high content of undesirable compounds. In contrast, ion–exchange is a very powerful technology capable of removing contamination from water. This paper analyses a study of ion exchange in Amberlite MB20 and Purolite MB400 resins after sulphate removal from a model solution. For the characterisation of ion exchange in resins, infrared spectroscopy was used. The IR spectra of both ion exchange resins show a similar composition after adsorption. Experiments that are due to this same used matrix in producing. The efficiency of sulphate ion removal and pH changes were also measured. Amberlite MB20 has proven to be a suitable ion exchange resin due to its high effi ciency (about 86%) for the removal of sulphates from solutions with initial concentrations of 100 and 500 mg.L-1, respectively

Precipitation of heavy metals from acid mine drainage and their geochemical modeling

Geochemical modeling plays an increasingly vital role in a number of areas of geoscience, ranging from groundwater and surface water hydrology to environmental preservation and remediation. Geochemical modeling is also used to model the interaction processes at the water - sediment interface in acid mine drainage (AMD). AMD contains high concentrations of sulfate and dissolved metals and it is a serious environmental problem in eastern Slovakia. The paper is focused on comparing the results of laboratory precipitation of metal ions from AMD (the Smolnik creek, Slovakia) with the results obtained by geochemical modeling software Visual Minteq 3.0

Determination of The Basic Characteristics of Sludge for Utilization in Building Cement Composites

This paper presents the results of basic research using sludge as a secondary material produced during the process of wet aggregates grading. The basic objective of this study was to identify important properties of sludge for the further use as substitute filler in the cement composites. Results of tests executed, like determination of particle size, bulk density, chemical composition (XRF method), mineralogical composition (XRD method) and both clay lumps and humus content were compared with those of natural aggregate (reference sample), as well as with standard criteria. For all tested properties, sludge shows satisfactory parameters, except the granularity. Here samples demonstrate high portions of fine particles in the 0/4 range. Thus can be concluded, sludge has a potential to be used as filler in cement composites requiring bigger amounts of fine particles, like self-compacting concretes

Quality of the bottom sediments in the area affected by mining activities

The remains of human activities may be seen in several places of the landscape in positive or negative form. Probably the most common phenomenon that fundamentally impacts the country is mining activity. The environmental problems caused by mining have attracted a great deal of research attention and led to development of numerous sediment heavy metal contamination assessment methods, including the index method, the dynamic method, the synthesis methods in chemistry, ecology and toxicology, etc. This research was undertaken in order to determine and analyze selected heavy metals present in sediment samples collected from different sampling localities inside and around water reservoir Ruzin, Slovakia. Reservoir and its inflows are located in the vicinity of region with historical Cu, Fe, Ag, Au-deposit, which was exploited from the 14th century to 1990 and currently causing environmental burden. For the determination of sediments quality different methods (XRD and XRF analysis) have been used. Based on the obtained data of analysis, potential ecological risk indices were used to study the pollution status of heavy metals in sediments and assess their potential ecological risk to environment. The calculated potential ecological risk indicates the level of water environment pollution by heavy metals in the sampling localities in the studied area