bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of effects of different parameters on supercritical fluid extraction of uranium from acidic solutions employing TBP as co-solvent
Authors: Rao Ankita , Kumar Pradeep , Ramakumar K. L.
Published: November 2008

In the supercritical fluid extraction of uranium from acidic medium employing TBP as co-solvent, effects of various parameters on extraction efficiency were studied. Variation in pressure (80–300 atm), temperature (308–353 K), CO2 flow rate (0.5–3 mL/min), co-solvent percentage (1–10%), molarity of nitric acid (0.5–10 M) were found to influence uranium extraction efficiency. The uranium extraction efficiency depends on distribution ratio and kinetics of transport of U-TBP complex into supercritical CO2. In the 150–300 atm pressure range, variation in extraction efficiency was similar to that of uranium distribution ratio under equilibrium conditions. Whereas below 150 atm, it closely followed supercritical CO2 density variation which could be attributed to non-equilibrium behavior that eventually attained equilibrium. In the non-equilibrium region, increased supercritical CO2 density with pressure favored enhancement in solubility as well as extraction kinetics of the U-TBP complex. Increase in temperature generally resulted in enhanced volatility of U-TBP complex and a decrease in supercritical CO2 density which in turn affected the extraction efficiency. Up to 333 K temperature, extraction efficiency gradually increased due to enhancement in volatility of U-TBP complex which more than compensates for decrease in the supercritical CO2 density. Beyond this temperature, the steep fall in the extraction efficiency is attributed to combined effect of saturation in volatility of the U-TBP complex and significant decrease in the density of supercritical CO2 approaching the critical value at which supercritical CO2 tends to form large clusters thereby resulting in steep decrease in its solvating power. Extraction efficiency was found to increase with nitric acid molarity up to 7 M and afterwards showed small decrease possibly due to competitive co-extraction of HNO3. Up to CO2 flow rate of 1 mL/min increase in extraction efficiency was observed which attained saturation afterwards. Linear increase in extraction efficiency was observed with the amount of TBP. Extraction efficiency was found to increase linearly with logarithm of extraction time. Under optimised conditions (150 atm, 333 K, 1 mL/min CO2 flowrate, 10% co-solvent, 7 M nitric acid and 30 min dynamic extraction time) extraction efficiency was found to be (98±2) was observed. 30 min dynamic extraction mode was found equivalent to 40 min static mode. Online complexation mode was more efficient than in situ mode.
Electrophilic synthesis of 6-[18F]fluoro-L-DOPA using post-target produced [18F]F2
Authors: Forsback Sarita , Eskola Olli , Haaparanta Merja , Bergmann Jörgen , Solin Olof
Published: November 2008

New diagnostic uses of 6-[ 18F]fluoro-L-DOPA ([ 18F]FDOPA) for endocrine cancers and for focal hyperinsulism of infancy have renewed interest in simple and reproducible methods to synthesize it in high quantity. Fluorodestannylation is a simple and regioselective means to produce [ 18F]FDOPA. We have successfully used post-target produced [ 18F]F2 as a labeling agent in fluorodestannylation. We are able to produce in one synthesis enough [ 18F]FDOPA for several human PET studies at Turku PET Centre. The average radiochemical yield in 50 syntheses was 6.4±1.7% (calculated from [ 18F]F−), with radiochemical purity >98% and mean specific radioactivity at the end of synthesis 3.7±0.9 GBq/μmol. With this method the amounts of the reagents used in the synthesis are considerably reduced in comparison to other electrophilic labeling approaches. Thus the manipulations during the synthesis and the purification of the product are simplified.
An Evidence of Various Rotamers of (E) 2-Hydroxyimino-2-cyanoacetic Acid Ethyl Ester by FTIR Spectroscopy
Authors: Rachwalska Malgorzata , Urbanek Zbigniew H.
Published: November 2008

FTIR spectra (50–4000 cm–1) were obtained in the temperature region 16–295 K for (E)2-hydroxyimino-2-cyanoacetic acid ethyl ester. A broadening of some peaks was observed while increasing the temperature. Broadening of the peak at 1187 cm–1 and its analysis vs. temperature enabled us to determine the barrier for CH2 twisting-rocking of 1.89±0.08 kJ/mole. The strong intensity dependence of the C=N stretching peak on temperature within the IR spectra is a sign of some nonlinear properties of the investigated substance. The splitting of several peaks connected with the C=N (azomethine), C=O and N-O vibrations provides evidence of two rotamers theoretically identified previously. The two rotamers existing distinctly (from the experimental point of view) at low temperatures differ one from the other only by 1 J/mol.
Preparation, Characterization and Application of Silver Chloride-Eosin Y Inclusion Material
Authors: Gao Hong-Wen , Bai Jing , Pei Xiao-Mei , Wang Hong-Yan , Wang Shi-Long
Published: November 2008

From the adsorptive precipitation of Cl–, eosin Y (EY) and Ag+, we developed in-situ inclusion of EY into growing silver chloride particles to form ternary electronegative micro-conductors. The composition of the particles was determined by inductively coupled plasma atomic emission spectrometry (ICP-OES), ion chromatography (IC) and spectrophotometry and the size and pattern of the particles characterized by the particle size analysis, X-ray diffractometer (XRD), scanning electron microscopy (SEM), and thermogravimetry. The results showed that the in-situ inclusion of EY into AgCl crystal particles in layer-by-layer and the supermolecular complex {[(AgCl)50EY]n}2n– was formed in cubic and globe-like shape. The ternary inclusion particles adsorbed cationic dyes selectively, rapidly and with high efficiency. A representative cationic dye, victoria blue B (VBB), was used to investigate the performance of the ternary particles as adsorbents and the mechanism involved. The equilibrium adsorption capacity of the ternary particles is 353 mg/g VBB, over 10 times higher than absorption to the silver chloride–only particles and over 3 times to activated carbon. Moreover, the adsorption approached the equilibrium in 10 min, which is much less than that with activated carbon in about 2 h. This work advanced a sample method for preparation of the supramolecular inclusion materials as dye adsorbent and it provided a simple, efficient and practical approach for the recovery or removal of organic substances from aqueous.
Heat Induced Charge Transfer in the Solid Solution Co3–xTx[Fe(CN)6]2 yH2O with T = Mn, Ni, Cu, Zn and Cd
Authors: Romero S. , Jimenez-Gallegos J. , Yee-Madeira H. , Reguera E.
Published: November 2008

Cobalt hexacyanoferrates have a relatively low energy barrier for the charge transfer between cobalt and iron atoms. That energy barrier can be overcome by irradiation with light in the ultraviolet-blue region or through the sample heating. Such feature for that charge transfer process is determined by structural and compositional factors. In this contribution the role of a second metal partially substituting to Co in the material composition on the heat induced charge transfer is studied. Samples of the solid solution Co3–xTx[Fe(CN)6]2yH2O with T = Mn, Ni, Cu, Zn and Cd, were prepared by a simple synthetic route and their behavior on moderate heating, from 80 to 160 °C, was evaluated. The behavior of the solid solution on heating was followed by infrared, X-ray diffraction and Mössbauer data. The heat induced charge transfer appears to be favored once the crystal water is removed, when the metal-metal interaction, through the CN bridges, reaches its maximum strength. From this fact, when a metal like Cu, Zn and Cd, with a relatively weak interaction with the coordinated water molecules and, as a consequence, with a low dehydration temperature, is present in the material structure, a lower activation energy is required to be able the heat induced charge transfer. Even in the presence of a second divalent transition metal occupying a fraction of the structural sites for Co, the charge transfer was observed, which is particularly pronounced in the 120–140 °C temperature range. The heat-induced charge transfer was also evaluated from the photo-induced inverse process in the heated samples using photo-acoustic spectroscopy.
Genetic Changes Accompanying the Evolution of Host Specialization in Drosophila sechellia
Authors: Dworkin Ian , Jones Corbin D
Published: November 2008

Changes in host specialization contribute to the diversification of phytophagous insects. When shifting to a new host, insects evolve new physiological, morphological, and behavioral adaptations. Our understanding of the genetic changes responsible for these adaptations is limited. For instance, we do not know how often host shifts involve gain-of-function vs. loss-of-function alleles. Recent work suggests that some genes involved in odor recognition are lost in specialists. Here we show that genes involved in detoxification and metabolism, as well as those affecting olfaction, have reduced gene expression in Drosophila sechellia—a specialist on the fruit of Morinda citrifolia. We screened for genes that differ in expression between D. sechellia and its generalist sister species, D. simulans. We also screened for genes that are differentially expressed in D. sechellia when these flies chose their preferred host vs. when they were forced onto other food. D. sechellia increases expression of genes involved with oogenesis and fatty acid metabolism when on its host. The majority of differentially expressed genes, however, appear downregulated in D. sechellia. For several functionally related genes, this decrease in expression is associated with apparent loss-of-function alleles. For example, the D. sechellia allele of Odorant binding protein 56e (Obp56e) harbors a premature stop codon. We show that knockdown of Obp56e activity significantly reduces the avoidance response of D. melanogaster toward M. citrifolia. We argue that apparent loss-of-function alleles like Obp56e potentially contributed to the initial adaptation of D. sechellia to its host. Our results suggest that a subset of genes reduce or lose function as a consequence of host specialization, which may explain why, in general, specialist insects tend to shift to chemically similar hosts.
A Novel Method of Distal End-Tidal CO2 Capnography in Intubated Infants: Comparison With Arterial CO2 and With Proximal Mainstream End-Tidal CO2
Authors: Kugelman Amir , Zeiger-Aginsky Dana , Bader David , Shoris Irit , Riskin Arieh
Published: November 2008

OBJECTIVE. The objective of this study was to evaluate a novel method of distal end-tidal CO2 capnography by comparison with Paco2 and with the more standard method that measures mainstream proximal end-tidal CO2 in intubated infants.

METHODS. Included in the study were all infants who were ventilated with conventional mechanical ventilation and intubated with a double-lumen endotracheal tube in our NICU during the study period. Data were collected prospectively from 2 capnographs simultaneously and compared with Paco2. Sidestream distal end-tidal CO2 was measured by a Microstream capnograph via the extra port of a double-lumen endotracheal tube. Mainstream proximal end-tidal CO2 was measured via capnograph connected to the endotracheal tube.

RESULTS. Twenty-seven infants (median [range] birth-weight: 1835 [490–4790] g; gestational age: 32.5 [24.8–40.8] weeks) participated in the study. We used for analysis 222 and 212 measurements of distal end-tidal CO2 and proximal end-tidal CO2, respectively. Distal compared with proximal end-tidal CO2 had a better correlation with Paco2 and a better agreement with Paco2. The accuracy of distal end-tidal CO2 decreased, but it remained a useful measure of Paco2 in the high range of Paco2 (≥60 mmHg) or in conditions of severe lung disease. A subanalysis for infants who weighed <1500 g (13 infants, 84 observations) revealed a good correlation and agreement between distal end-tidal CO2 and Paco2 and poor correlation and agreement for proximal end-tidal CO2.

CONCLUSIONS. Distal end-tidal CO2 measured via a double-lumen endotracheal tube was found to have good correlation and agreement with Paco2, remained reliable in conditions of severe lung disease, and was more accurate than the standard mainstream proximal end-tidal CO2.
Islet adaptive changes to fructose-induced insulin resistance: β-cell mass, glucokinase, glucose metabolism, and insulin secretion
Authors: Maiztegui B , Borelli M I , Raschia M A , Del Zotto H , Gagliardino J J
Published: November 2008

β-Cell mass, hexokinase/glucokinase (HK/GK) activity, glucose metabolism and insulin secretion were studied in the islets of rats with fructose-induced insulin resistance (IR). Normal male Wistar rats were fed a standard commercial diet and water without (control, C) or with 10% fructose-rich diet (FRD) for 3 weeks. Blood glucose (strips), triglyceride (commercial kit), and insulin (RIA) levels were measured at the time of death. Glucose-induced insulin release, glucose metabolism (14CO2 and 3H2O production from d-[U-14C]- and d-[5-3H]-glucose) and HK/GK activity (G-6-P production), transcription (RT-PCR), protein expression (Western blot), and cellular compartmentalization were measured in isolated islets (collagenase digestion). FRD rats presented normoglycemia but impaired glucose tolerance, hypertriglyceridemia, hyperinsulinemia, and increased HOMA-IR index. In these rats, β-cell mass decreased significantly by 33%, with a 44% increase in the percentage of apoptotic cells. Glucose-induced insulin release and islet glucose metabolism were higher in FRD rats. While GK activity (total and cytosolic fraction) and protein expression were significantly higher in FRD islets, HK showed no change in any of these parameters. Our results demonstrate that the changes induced by dietary-induced IR upon β-cell function and mass are strongly conditional on the nutrient model used. In our model (intact animals with impaired glucose tolerance), GK activity increases through mechanisms previously shown only in vitro or under highly hyperglycemic conditions. Such an increase plays a pivotal role in the adaptive increased release of insulin in response to IR, even in the presence of marked β-cell mass reduction.
Interaction characteristics of geosynthetics with fine tailings in pullout test
Authors: Yin G. , Wei Z. , Wang J. G. , Wan L. , Shen L.
Published: November 2008

New mining technologies not only exploit lower-grade ores but also produce a much higher volume of tailings as mining waste. The disposal of these tailings is a challenge for mine operators. A tailings dam is usually constructed to store these wastes safely. The dam continuously increases its height and changes geometry with the disposal of tailings, which is different from conventional dams. Therefore the stability of tailings dams is a challenge. Geosynthetics have been widely used as reinforcement in retaining walls and embankments, but their applicability to the construction of tailings dams has not previously been studied. Their applicability depends largely on the interaction between geosynthetics and fine tailings. In this paper, the interaction of geosynthetics (geobelt and geogrid) with fine copper ore tailings is studied through laboratory pullout tests. The test results reveal that the interaction characteristics are influenced by tailings particle size, density, moisture content, and vertical load. It is found that the maximum friction coefficient between geosynthetics and the fine tailings is less than 0.22, which is lower than the published data for natural soils.
Puncture resistance of PVC geomembranes using the truncated cone test
Authors: Stark T. D. , Boerman T. R. , Connor C. J.
Published: November 2008

This paper presents an experimental study to develop a design procedure for the puncture behavior of polyvinyl chloride (PVC) geomembranes. The puncture resistance was measured using the truncated cone test, in which truncated cones are used as puncture points. The heights of the truncated cones are varied to determine the critical cone height, which is the height at which geomembrane puncture occurs for a given pressure. A cushion geotextile is not used in any test to enhance puncture resistance because of the large cone heights required to puncture PVC geomembranes. Critical cone heights are presented for 0.5 mm, 0.75 mm and 1.0 mm thick PVC geomembranes. The results of these tests show that as the thickness of the PVC geomembrane increases, the critical cone height increases. This indicates an increased puncture resistance with increasing geomembrane thickness. The results of the puncture tests on PVC geomembranes are compared with other types of geomembrane, e.g. smooth and textured 1.5 mm thick high-density polyethylene and 1.0 mm thick linear low-density polyethylene. This comparison shows that the puncture resistance of PVC geomembranes used in this investigation exceeds that of polyethylene geomembranes, even though the PVC geomembranes are thinner.
Characteristics of ACPDP test panels with aluminum fence electrode formed via anodic bonding with soda‐lime glass
Authors: Lee Seog‐Young , Lee Mi‐Yeon , Choi Won‐Yeol , Lee Dong‐Heon , Kim Yong‐Seog
Published: November 2008

Abstract— In an attempt to reduce materials and processing costs of ACPDPs, aluminum fence electrodes were prepared on soda‐lime glass substrates by chemically etching aluminum foil bonded directly onto the substrate via an anodic‐bonding process. Several different fence‐electrode patterns were designed and coated either with a glass dielectric layer or with an anodic aluminum oxide layer. Firing voltages, operation margin, luminance, and luminous efficiency of such test panels were evaluated. The results indicated that the performance of test panels with aluminum fence electrodes is comparable with conventional test panels with ITO/Ag electrodes, demonstrating the possibility of a dramatic reduction in the costs of ACPDPs.
Contrast gain and power savings using local dimming backlights
Authors: Langendijk Erno H. A. , Muijs Remco , van Beek William
Published: November 2008

Abstract— The contrast and power consumption of today's liquid‐crystal displays (LCDs) can be improved substantially by introducing (local) dimming backlights. In fact, infinite dynamic contrast and power savings of well over 50% have been claimed for such displays. Because these claims are generally made for very specific backlight designs and image content, the contrast gain and power savings are quantified as a function of the number of backlight segments for a large variety of image content.
A 5‐in. flexible ferroelectric liquid‐crystal display driven by organic thin‐film transistors
Authors: Fujisaki Yoshihide , Sato Hiroto , Takei Tatsuya , Yamamoto Toshihiro , Fujikake Hideo , Tokito Shizuo , Kurita Taiichiro
Published: November 2008

Abstract— An organic thin‐film‐transistor (OTFT) driven color flexible ferroelectric‐liquid‐crystal (FLC) display with 160 × 120 pixels and a resolution of 50 ppi has been developed. The flexible FLC was fabricated on a pentacene‐OTFT array using printing and lamination techniques. To drive the display at a fast driving speed, an OTFT was developed with a short channel length having a large current output. The fabricated OTFT array with a channel length of 5 μm exhibits a carrier mobility of 0.3 cm2/V‐sec and an ON/OFF ratio of over 107 at a low drain voltage of −6 V. A field‐sequential‐color system with a flexible backlight unit was also developed and used to drive the display. Color moving images were successively shown on the 5‐in. display using an active‐matrix driving technique of the OTFT.
Impact of Phakopsora pachyrhizi Infection on Soybean Leaf Photosynthesis and Radiation Absorption
Authors: Kumudini S. , Prior E. , Omielan J. , Tollenaar M.
Published: November 2008

Yield loss in soybean [Glycine max (L.) Merr.] due to soybean rust (SBR) (caused by Phakospora pachyrhizi Syd. & P. Syd.) has been associated with reduced radiation interception and reduced radiation use efficiency by green leaf area. The objective of this study was to determine the mechanisms involved in the SBR‐induced reductions in radiation use efficiency by quantifying the effect of SBR on (i) absorption of photosynthetic photon flux density (PPFD) and (ii) carbon exchange rate (CER) per unit absorbed PPFD of soybean leaves. A controlled‐environment study was conducted using a split‐plot design with three replications over time, with two disease levels as main plots and two soybean cultivars as subplots. The two disease levels were a disease‐free control and inoculation with P. pachyrhizi. Measurements included leaf CER, PPFD absorptance, and chlorophyll fluorescence. As disease severity increased, there was a small linear decline in leaf absorptance and a negative exponential decline in leaf CER. At 50% disease severity, absorptance was reduced by 10% and CER was reduced by 68% compared with the disease‐free control. The relative decline in CER was similar at low and saturating PPFD levels. Soybean rust–induced reductions in CER were mainly associated with lower efficiency of photosystem II (PSII) photochemistry and damage to PSII reaction centers. Therefore, visual indicators such as light absorptance and disease severity do not reflect the degree of impact of SBR on leaf photosynthesis.
Phosphorus recovery in aerated systems by MAP precipitation: optimizing operational conditions
Authors: Stumpf D. , Zhu H. , Heinzmann B. , Kraume M.
Published: November 2008

An attractive way of recovering essential phosphorus from digested sludge of a WWTP is the precipitation in the sludge directly, as part of the continuous treatment process. For optimizing the precipitation, 1 litre-batch tests were performed in a model system to examine the MAP-crystallization kinetics. Different parameters such as e.g. the aeration flow rate were investigated. The aim was to find an optimized setting for a pilot reactor for the continuous production of MAP. This reactor performed as an airlift reactor for an improved mixing and stripping the dissolved CO2 and separating the MAP-crystals. The optimal condition for the airlift pilot reactor is given when the air flow rate for mixing the system and for stripping CO2 for a maximum MAP precipitation is aligned with the particle size distribution.
Coupled removal of organic compounds and heavy metals by titanate/carbon nanotube composites
Authors: Doong Ruey-An , Chiang Li-Fen
Published: November 2008

The objective of this study was to fabricate 1-dimensional (1-D) nanocomposite materials with high aspect ratios and specific surface areas for the coupled degradation of refractory organic compounds and heavy metals. The 1-D nanomaterials were composed of various ratios of carbon nanotubes (CNT) and titanate nanotubes (TNT) (CNT/TNT). Alkaline hydrothermal method was used to fabricate TNT under various hydrothermal conditions. The morphology changed from nanoparticles/nanosheets, nanotubes, nanowires and then to nanoribbon as the hydrothermal temperatures increased from 60 to 230°C. In addition, the CNT/TNT nanomaterials have a good capability toward heavy metal adsorption. The Langmuirian maximum adsorption capacities of nanomaterials were in the range 83–124 mg/g for Cu2 +  and 192–588 mg/g for Pb2 + , which is superior to that of CNT. The removal efficiency of Cu2 +  by CNT/TNT decreased when 40 mg/L MX5B was due to the complexation of MX5B with Cu2 + . Results obtained in this study clearly show the 1-D CNT/TNT nanomaterials are a promising nano-adsorbent for coupled removal of organic as well as heavy metal ions in solution.
The combined approach—a challenge for border crossing water quality issues in Austria
Authors: Zessner M.
Published: November 2008

Is it sufficient to meet threshold values downstream of a discharge, even if this leaves no more space for future development? Is it simply bad luck for a downstream country, if threshold values are filled up at the border and there is no more space for additional emissions? If not: what are the criteria to distribute acceptable emissions between countries and regions? Who pays according to the “polluter pays” principle in a case, if several polluters contribute to the pollution, but the most cost-effective measures to reach the good status concern only some of the emitters/enterprises? There are little experiences with those and other related questions in Austria and many other EU-member states. This contribution intends to discuss these issues based on actual problems and would like to raise awareness for several of these unsolved questions.
Ecological stabilization of thickened wastewater sludge from CAST process
Authors: Cui Y. B. , Wu X. H. , Liu Zh. Sh. , Liu J. Zh. , Lin Y. Z.
Published: November 2008

Wastewater sludge ecological stabilization (WWSES) pilot scale experiments were conducted for thickening treatment and disposal of sludge which came from Cyclic Activated Sludge Technology (CAST) process. The study was performed over the periods from June to November 2005 and from May to November 2006, on a bed of 80 m2. The sludge loadings were stopped for the winter from December 2005 and resumed in May 2006. The results shows that dried sludge layer has higher permeation coefficients of 0.15–1.3 m/h. It is suggested that the percolate did not filtrate downwards evenly, part of percolate filtrates downwards along stems, roots and cracks existing in dried sludge which have lower flow resistance. The relationship of dried sludge thickness and operation time is in accord with quadratic equation under fluctuating sludge loadings. Linear regression equation can indicate dried sludge thickness variation under fixed sludge loading. In comparison with natural ones, coarse protein content of Phragmites australis roots in the system is twice as high, coarse fiber content of roots, coarse fat content of stems and leaf are obviously higher; and coarse protein content of Typha augustifolia in the system are obviously higher, while coarse fat and coarse fiber contents have no significant difference.
Institutional and legal arrangements in the Nile river basin: suggestions to improve the current situation toward adaptive integrated water resources management
Authors: Abdalla Khalid Mohamed El Hassan
Published: November 2008

A comparative study was conducted in this work in order to investigate the current situation in the Nile river basin (NRB) regarding the institutional and legal arrangements needed to support the adaptive integrated water resources management (AIWRM) strategy. Two similar river basins were selected to achieve this comparison and to introduce suggestions to reform the current situation in the basin. Before that, the ideal situation is investigated to be as a yardstick for the desired situation. The study indicated that the necessary AIWRM criteria may include regulatory as well as implementation organizations that support shared-vision reaching with its all necessary features (cooperation, stakeholders' participation, subsidiarity, and information and knowledge exchange). Thus the main features of the desired situations regarding AIWRM in river basins are stakeholders' participation, learning-driven ability, quick response to risks and uncertainties, and finally a legal framework that could support these criteria. Although the AIWRM criteria seem to be satisfied in NRB, the basin lacks the necessary regulatory institutions as well as the legal framework. According to this, this study recommends to reform the current situation in NRB by creating regulator institutions (policy and decision making level) as well a legal framework to legitimate them.
New process for alleviation of membrane fouling of modified hybrid MBR system for advanced domestic wastewater treatment
Authors: Shuo Liu , Baozhen Wang , Hongjun Han , Yanping Liu
Published: November 2008

A pilot-scale hybrid membrane bioreactor using a submerged flat panel membrane was designed and applied for advanced treatment of domestic wastewater. The new process adapted to the hybrid membrane bioreactor exhibits substantial decrease in membrane fouling and much easier cleaning. In this study, the new process configurations including the addition of anoxic/anaerobic zones, the package of synthetic fibrous fabric carrier for biofilm attached growth, activated sludge recycling and modified dosage of polished diatomite with high activity and multi-functions were investigated to select the optimal operational parameters for the hybrid membrane bioreactor system. The carrier package in the aerobic zone contributed 3.65 g/L (maximum) of fixed biomass to the system, thus reducing the suspended biomass, and has decreased the membrane cleaning cycle remarkably. The operation performance at the sludge recycle rate 0, 100%, 200% and 300% showed that, the trans-membrane pressure of flat panel membrane declined sharply with the increase of sludge recycling rate within a certain range, and 200% was decided to be optimal for in the membrane bioreactor system. EPS concentration in each sludge recycling rate was 135 mg/L, 92 mg/L, 68 mg/L and 55 mg/L respectively. The addition of anoxic and anaerobic zones degraded some large molecular organic compounds, which facilitated the biodegradation and removal of organic substances in aerobic zone. The modified dosage of polished diatomite has played a major important role for both preventing of membrane from fouling and its much easier cleaning when it formed.
Elements for setting up discharge standards in developing countries based on actual wastewater treatment plant performance
Authors: Oliveira Sílvia C. , von Sperling Marcos
Published: November 2008

The paper analyses the capability of 166 full-scale wastewater treatment plants operating in Brazil, in order to achieve different quality targets for wastewater discharge. These targets cover a wide range of possible situations, reflecting usual practices adopted worldwide. Six different treatment processes have been investigated: septic tank + anaerobic filter, facultative pond, anaerobic pond + facultative pond, activated sludge, UASB reactors alone, UASB reactors followed by post-treatment. The parameters investigated were: BOD, COD, suspended solids, total nitrogen, total phosphorus and thermotolerant coliforms. Most technologies showed a poor performance, and some of them were not capable to achieve even relaxed standards. The paper presents elements for setting up discharge standards in developing countries, based either on values that may be achieved by treatment processes commonly applied or on best available technologies.
Electrostatic repulsion as a mechanism in fouling of ultrafiltration membranes
Authors: Arkhangelsky Elizabeth , Levitsky Inna , Gitis Vitaly
Published: November 2008

Studies of electrostatic repulsion in ultrafiltration membranes are limited to applications of different organic compounds carrying a set of unique characteristics, or to changes of general water parameters such as ionic strength and pH. The proposed method of deliberate alteration of surface charge of organic molecule by succinylation or by guanidination provides an opportunity to selectively investigate the electrostatic mechanism without changing size or hydrophobic properties of investigated molecule. The approach was successfully implemented on BSA protein, and new inside into the mechanism of electrostatic mechanism was obtained. The electrostatic repulsion becomes important when zeta potential of the protein exceeded 20 mV, when before the threshold the interactions were mainly governed by size exclusion.
Intrathoracic goiter: Analysis of 21 cases
Authors: Ignjatovic Mile , Stanic Vojkan , Cuk Vladimir , Kostic Zoran
Published: November 2008

Goiters are classified into: the cervical, retrosternal, substernal and intrathoracic. The aim of research is to analysis of intrathoracic goiters (ITG) which include goiters with more than 80% of tissue in the thoracic cavity and intrathoracic thyroid choristomas. Methods: In prospective non-randomized study were analyzed 21 consecutive patients operated on for intrathoracic non-toxic benign goiters from 1987-98. Fourteen patients with intrathoracic goiters (more than 80% of tissue in the thoracic cavity) and seven patients with intratoracic choristomas were operated. Two groups of ITG were observed according to the expressed symptomatology and surgical approach and complications of operative treatment were compared to the complications of operative treatment of 986 non-ITG non-toxic benign goiters. Results: ITG represented 1,1% of the whole number of operatively treated thyroid diseases. One third of patients were asymptomatic. Commonly observed symptoms were dispnea, stridor and dysphagia and there was no significant difference in appearance of these symptoms between the two groups of ITG. In 19% of patients correct preoperative diagnosis wasn't assessed. Cervical approach with sternothomy was used in 11 patients, cervical approach with right thoracotomy in seven, right thoracotomy only in two, and cervical approach only in one patient. Thoracic approach was used in 95% of cases and there was no significant difference between the two groups of ITG. Concerning the operative complications, in two patients transient vocal cord paresis and in one patient postoperative bleeding were verified. There was no statistically significant deference in frequency of operative complications between ITG and non-ITG. Conclusions: ITG are rare, but might present a difficult diagnostic and complex surgical problem. Common clinical presentation and identical surgical approach in operative treatment justify the common review of the two groups of intrathoracic goiters. With adequate and timely performed surgical approach, in specialized institutions, frequency of complications in operative treatment of ITG is not higher if compared to operative treatment of non-ITG.
Acute hemolytic transfusion reaction
Authors: Vucelic Dragica , Savic N. , Djordjevic R. , Djokic Milan , Vavic Natasa , Velimirovic I.
Published: November 2008

Alloogenous blood and/or corresponding haemoproduct transfusion is an efficient and relatively safe supportive treatment. Despite the fact that pre transfusion investigation of both patients and donors ensure high degree of safety of this type of treatment, occurrence of adverse haemotherapy effects is possible and often unpredictable. Acute haemolytic transfusion reaction occur as a consequence of immune conflict between red blood cell membrane agents and specific antibodies present in plasma. Since it is impossible to completely avoid the occurrence of transfusion reactions, wherein acute transfusion haemolytic reaction present a serious, possibly life threatening complication, it is an imperative to continue to improve the knowledge on pathogenesis mechanisms leading to complications associated with these reaction and to define the most efficient therapeutical modalities.
TRALI syndrome: Noncardial lung oedema after blood transfusion
Authors: Masirevic Vesna , Colovic Radoje , Basic Marica , Rankovic Vitomir , Palibrk I. , Ivic Ljiljana
Published: November 2008

Definition - signs and symptoms which include dispnea, hypertension, high temperature and high productive tracheobronchial secretion. Physical findings are lung oedema in first four hours. Such patients usually require respiratory help. After adequate therapy, symptoms disappeared in 96 hours. In the beginning, TRALI used to be a part of ARDS and it were treated that way. Today, TRALI is understand like substantive group of symptoms.
Management of severe anemia in Jehovah's witness patient with gastrointestinal hemorrhage: Case report
Authors: Stamenkovic Dusica , Randjelovic Tomislav , Zoric Sava , Bilanovic Dragoljub , Basara S.
Published: November 2008

This case report describes the treatment of 67-year-old Jehovah's Witness with severe anemia and gastrointestinal haemorrhage from gastric leiomyoma and peptic ulcer. Minimal invasive surgery with meticulous hemostasis, controlled hypotension, hyperoxic normovolemia and normotermia were main principles. Minimal blood samples for necessary laboratory parametars and noninvasive monitoring were ways to decrease iatrogenic blood loss. The operative and postoperative period were uneventful and well tolerated. The patient was discharged home after eighteen days and well in follow up period.
Modern concepts for the treatment of fecal incontinence
Authors: Rosen H.R.
Published: November 2008

Anal incontinence is estimated to be present in approximately 2% of the total population. However, the incidence of this disorder increases with age, affecting up to 11% of men and 26% of women after the age of 50 years. In general, the causes of long-standing fecal incontinence may be divided into anorectal or congenital malformations, perineal trauma (due to surgery or accident), pudendal nerve lesions with or without muscular injury, and low-motor neuron lesions. Classical surgical treatment includes direct repair of the circumscribed gap in the anal sphincter, the so-called overlapping sphincteroplasty or anal repair. In the short term, this method was shown to be very effective in improving continence. Surgical repair of a diffuse weakness of the pelvic floor by application of the postanal repair method has led to more controversial results. While the short-term results are frequently beneficial, full continence is rarely achieved in the long run, especially in patients with impaired pudendal nerve function. All currently used surgical methods focus on the direct mechanical approach to the pelvic floor muscles and/or the anal sphincter. Therefore, the response to this kind of therapy is limited by the presence of a simultaneously existing neurogenic lesion (pudendal nerve damage), as "ell as by the magnitude and intensity of muscular injury. These problems have been addressed by the development of new methods that focus on the replacement of large muscular defects (Dynamic Graciloplasty) and the treatment of neurogenic causes of fecal incontinence (Sacral Nerve Stimulation - SNS).
Preserving the superior rectal artery in laparoscopic anterior resection for complete rectal prolapse
Authors: Ignjatovic D. , Bergamaschi R.
Published: November 2008

Anterior resection for the treatment of full thickness rectal prolapse has been around for over four decades. 1 However, its use has been limited due to fear of anastomotic leakage and related morbidity. It has been shown that high anterior resection is preferable to its low counterpart as the latter increases complication rates. 2 Although sparing the inferior mesenteric artery in sigmoid resection for diverticular disease has been shown to decrease leak rates in a randomized setting, 3 vascular division is current practice. We shall callenged this current practice of dividing the mesorectum in anterior resection for complete rectal prolapse developing a technique that allows the preservation of the superior rectal artery.
Sacral magnetic stimulation in puborectalis paradoxical syndrome
Authors: Shafik A.
Published: November 2008

Background and Purpose: Our earlier studies have demonstrated that sacral magnetic stimulation (IMS) in the canine model, in healthy volunteers and in constipated subjects effected rectal pressure rise, decline of the rectal neck (anal canal) pressure as well as rectal evacuation. Based on these results, we studied the effect of sacral MS on defecation in patients with puborectalis paradoxical syndrome (PPS). Methods: Eleven subjects (8 women, 3 men; age 36-53 years) with PPS were enrolled in the study. The magnetic coil was placed on the back with its center located between L4 and L5. Stimulation parameters were set at 70% of maximum intensity, 40 Hz frequency and 2-second burst length with 2 seconds off. During MS, the rectal neck and gastric (intra-abdominal) pressures were measured. The procedure was performed in the empty and in the full rectum using the balloon expulsion test in the latter. Results: MS of the empty and balloon-filled rectum effected rise of the rectal pressure (p<0.001), decline of the rectal neck pressure (p>0.001) and no significant change of the intragastric pressure (p>0.05). The balloon was expelled to the exterior in all the patients. Conclusions: Sacral MS succeeded in dispelling to the exterior the water-filled rectal balloon. The method is simple, easy, non-invasive, non-radiologic and can be performed on an outpatient basis for the treatment of PPS.
Perspectives and controversies in the treatment of advanced colorectal cancer: From paliation to cure
Authors: Popov Ivan
Published: November 2008

Advanced colorectal cancer (ACRC) has been traditionally considered resistant to chemotherapy, with no clear benefit in relation to time to progression and overall survival. Nevertheless, nowadays first and second line therapeutic approaches have dramatically changed the natural history of ACRC, and that means that at present the most important decision in a patient is not to treat or no to treat with chemotherapy, but to choose the best chemotherapy schedule at any time. Following this purpose it has been necessary, not only the emergence of new drugs and schedules, but also the understanding of the clinical efficacy. Actually, to the classic parameters such as, objective response, time to progression, and overall survival, new parameters studying clinical benefit have been added. Among these new parameters we can find the weight loss, symptom-free period, quality of life, pain-free interval, etc. Therefore, the really important aim in these situations is the patient clinical status, being less important the survival or the tumor burden reduction.
New approaches in ambulatory proctology
Authors: Skricka T. , Vedra P.
Published: November 2008

Ambulatory proctology is till now very underestimated discipline, which is out of interest of big surgeons. But is a very important field due to incidence of proctological affections and severe social consequences of their inappropriate diagnosis and treatment. We stress the conservative and semiinvasive treatment of hemorrhoids, anal thrombosis and anal fissures. We also mention the other anal pathologies.
New approaches to the treatment of anal fissure
Authors: Dziki A. , Trzcinski R. , Langner E. , Wronski W.
Published: November 2008

According to Antropoli, pathologies of the anal canal are extremely common. About 30 to 40 percent of the population suffers from proctologic pathologies at least once in their lives. In most cases they are more annoying than dangerous. Anal fissure (AF) was recognized as a clinical entity in 1934 . It is a longitudinal defect of the anal canal mucosa and anoderm extending usually from the dentate line to the external verge of the anal canal. This defect exposes the lower half or even most of the fibres of internal anal sphincter. AF is almost always accompanied by extensive tension of this muscle. Anal fissures affect all age groups but predominantly occur in the 3rd and 4th decades of life (2,8,23). Gathright states that fissure disease causes from 6 to 15% of office visits and 10% of operative procedures in a colorectal practice. The etiology of anal fissure has only been partially explained and remains controversial although spasm of the internal anal sphincter has been recognized to play a main role in the pathogenesis of this disease. Recent studies have cast new light on the pathogenesis of anal fissures.
Znacaj splenektomije u lecenju bolesnika sa "hairy cell" leukemijom
Authors: Gotic Mirjana , Popovic M. , Petrovic M. , Cemerikic-Martinovic Vesna , Elezovic Ivo , Tomin Dragica , Bila J. , Boskovic Darinka
Published: November 2008

"Hairy cell" leukemija (HCL) je retka i neuobicajena forma hronicne limfoidne leukemije sa ne-predvidljivim tokom. Splenomegalija je najucestaliji klinicki nalaz a vecina drugih manifestacija je direktna posledica citopenije i splenomegalye. Splenektomija kao terapijski tretman, eliminise ne samo efekat "pooliranja" krvnih celija u slezini, vec dovodi i do uklanjanja glavnog mesta leukemijske celijske proliferacije. U nasem radu retrospektivno smo analizirali 38 bolesnika sa dijagnozom HCL kod kojih je splenektomija primenjena kao prva linija terapije. Rezultati lecenja bolesnika sa HCL-om primenom splenektomije su pokazali da je 22/38 bolesnika (58%) i dalje u hematoloskoj remisiji (u periodu pracenja od 7 godina) primenom samo ovog terapijskog modaliteta, a da je 16/38 bolesnika (42%) progrediralo krace ili duze vreme nakon splenektomije i nastavilo lecenje alfa interferonom kao drugom linijom terapije. Medijana duzine remisije nakon splenektomije je bila 36 meseci. Medjutim, analiza veceg broja klinickih i hematoloskih parametara definisala je prognosticki povoljnu grupu bolesnika sa HCL-om kod koje je splenektomija kao inicijalno lecenje dovela do dugotrajne hematoloske remisije (medijana: 72 meseca). S druge strane, kod prognosticki nepovoljne grupe bolesnika sa HCL-om splenektomija je kao inicijalno lecenje dovela do kratkotrajne hematoloske remisije (medijana: 6-7 meseci) i bolesnici su ubrzo nastavili lecenje alfa interferonom. Na osnovu nasih rezultata a uzimajuci u obzir i literaturne podatke, inicijalna splenektomija imala bi najveci uspeh kod grupe bolesnika sa HCL-om sa povoljnom prognozom i vrednostima hematoloskih parametara: hemoglobin > 110 g/l, broj trombocita > 130xl0^9/l i stepen infiltracije kostne srzi < 70%. Kod bolesnika sa nepovoljnom prognozom i vrednostima hemoglobina < 90 g/l, broja trombocita < 60xl0^9/l i stepena infiltracije kostne srzi 90%, efekat splenektomije je kratkotrajan, tako da je svrsishodnije inicijalno primeniti sistemsku terapiju alfa interferonom ili purinskim analozima.
Parcijalna resekcija slezine u lecenju benignih i traumatskih lezija
Authors: Radevic Bozina , Dugalic V. , Jesic Rada , Sagic Dragan , Perisic V. , Nenezic D. , Popov P. , Ilijevski Nenad , Gajin P. , Vucurevic G. , Radak Djordje , Trebjesanin Z. , Babic D. , Matic P.
Published: November 2008

It has been thought that the spleen is an organ without important functions, until recently. That is, why splenectomy has been the procedure of choice in a treatment of splenic diseases. Even now, when we know the functional importance of the spleen, splenectomy is performed frequently, regardless of its complications.The need of spleen functions salvage, favours partial resection of the spleen as competitive in a treatment of its traumatic and benign lesions. Improvement in diagnostic procedures, surgical techniques, transfusiology and postoperative treatment, will promote it as a treatment of choice. The authors of this study have experience with 17 partial resections of the spleen for traumatic, 11 for benign lesions of the spleen, and one ectopic spleen with hypersplenism, without mortality and with insignificant complications.
Surgical therapy of hematological disorders of spleen
Authors: Milovanovic Aleksandar , Popovic Milos , Petrovic M. , Colovic Radoje , Boskovic D. , Colovic Milica , Elezovic Ivo , Matic Slavko , Zuvela M. , Knezevic S. , Dugalic V. , Antic A.
Published: November 2008

Splenectomy - the surgical removal of spleen is being performed in cases of: traumatic spleen rupture, as part of other surgical procedures, number of hematological, infectious and metabolic disorders. During the years 1988-2001, there were 396 splenectomies performed at the First surgical clinic, for the cause of: autoimmune disorders 187 (47,34%), lymphoproliferative diseases 89 (22,59%), Hodgkin disease 35(8,94%), myeloproliferative disease 39 (9,95%), as part a of "staging" laparotomy 37 (9,34%), other hematological disorders 7 (2,20%). The spleen of 244 patients weighted 500-1500 g (61,62%), in 56 patients (14,14%) weighted less than 500g, and in 96 patients (24,24%) spleen weighted more than 1500 g . Patients with thrombocytes less than 40000/l 16 (4,04%) were perioperativly treated with fresh thrombocytes. Postoperative morbidity and mortality were registered in 54 (13,64%), i.e. 8 (2.02%) patients. Delayed results depended on primary disorder, comorbidities and supportive therapy. In this article, the particularities of the operative procedure were discussed, as well as importance of cooperation of surgeon and hematologist in perioperative treatment.