Techno-economic analysis of the scale-up process of electrochemically-assisted soil remediation.

This work presents a techno-economic study of the scaling-up of the electrochemically-assisted soil remediation (EASR) process of polluted soil. Four scales have been selected for the study: laboratory, bench, pilot and prototype, with a capacity of treating a volume of soil of 1 × 10-4, 2 × 10-3, 0.11 and 21.76 m3, respectively. This study analyses the technical information produced by studies carried out at each scale, and informs about the fixed costs (construction of the electrokinetic remediation reactor, installation of auxiliary services and purchase of analytical equipment) and variable costs (start-up, operation and dismantling of the test) derived from running a test at each of the evaluated scales. The information discussed in based on the experience gained with many evaluations carried out over the last decade at these scales. This information can provide useful guidance for developing a scaling-up of the EASR for many researchers starting on the evaluation of this important environmental remediation technology.

Ileocolic intussusception: Ultrasound-guided hydrostatic reduction with sedation and analgesia.

INTRODUCTION: The first-choice treatment for ileocolic intussusception is imaging-guided reduction with water, air, or barium. The objectives of the current study were to evaluate the efficacy and safety of ultrasound-guided reduction of intussusception using water in patients under sedation and analgesia. We compare this approach with our previous experience in reduction using barium under fluoroscopic guidance without sedation and analgesia and investigate what factors predispose to surgical correction. MATERIAL AND METHODS: We retrospectively reviewed cases of children with ileocolic intussusception treated in a third-level pediatric hospital during a 52-month period: during the first 24 months, reduction was done using barium and fluoroscopy without sedoanalgesia, and during the following 28 months, reduction was done using water and ultrasound with sedoanalgesia. A pediatric radiologist and a pediatrician reviewed the clinical history, surgical records, and imaging studies. RESULTS: In the 52-month period, 59 children (41 boys and 18 girls; mean age, 16.0 months) were diagnosed with ileocolic intussusception at our hospital. A total of 33 reductions (28 patients and 5 recurrences) were done using barium under fluoroscopic guidance, achieving a 61% success rate. A total of 38 reductions (31 patients and 7 recurrences) were done using water under ultrasound guidance with patients sedated, achieving a success rate of 76%. No significant adverse effects were observed in patients undergoing ultrasound-guided hydrostatic reduction under sedation, and the success rate in this group was higher (p = 0.20). The factors that predisposed to surgical reduction were greater length of the intussusception (p = 0.03), location in areas other than the right colon (p = 0.002), and a greater length of time between symptom onset and imaging tests (p = 0.08). CONCLUSION: Ultrasound-guided hydrostatic reduction of ileocolic intussusception under sedoanalgesia is efficacious and safe.

Scale-up of electrokinetic permeable reactive barriers for the removal of organochlorine herbicide from spiked soils.

This work aims to shed light on the scale-up a combined electrokinetic soil flushing process (EKSF) with permeable reactive barriers (PRB) for the treatment of soil spiked with clopyralid. To do this, remediation tests at lab (3.45 L), bench (175 L) and pilot (1400 L) scales have been carried out. The PRB selected was made of soil merged with particles of zero valent iron (ZVI) and granular activated carbon (GAC). Results show that PRB-EKSF involved electrokinetic transport and dehalogenation as the main mechanisms, while adsorption on GAC was not as relevant as initially expected. Clopyralid was not detected in the electrolyte wells and only in the pilot scale, significant amounts of clopyralid remained in the soil after 600 h of operation. Picolinic acid was the main dehalogenated product detected in the soil after treatment and mobilized by electro-osmosis, mostly to the cathodic well. The transport of volatile compounds into the atmosphere was promoted at pilot scale because of the larger soil surface exposed to the atmosphere and the electrical heating caused by ohmic losses and the larger interelectrode gap.

Electrokinetic-Fenton for the remediation low hydraulic conductivity soil contaminated with petroleum.

The use of electrokinetic Fenton (EK Fenton) process, as promising soil remediation approach, was investigated by using an iron electrode with different supporting electrolytes (tap water, H2O2, and citric acid) to depollute soil spiked with petroleum where kaolin was selected as low hydraulic conductivity. The results clearly confirm that, the combination of electrokinetic remediation (EK) and Fenton technologies, is an efficient oxidizing approach for removing hydrocarbons from this kind of soil. In fact, the electrokinetic Fenton reactions and the control of the soil pH conditions by adding citric acid enhanced the oxidation process because the addition of the H2O2 with iron electrode resulted in higher removal efficiencies (89%) for total petroleum hydrocarbons (TPHs). These figures allowed to confirm that EK Fenton process with pH control contributed for the transport of H2O2 and Fe2+ ions in the soil by electromigration and eletro-osmotic phenomena. Conversely, no control of pH conditions when only EK was applied, achieved lower hydrocarbons removal (27%) after 15 d of treatment due to the precipitation of iron ions. Finally, the efficiency of the EK Fenton remediation prevented the generation of secondary effluent with higher organic content, avoiding its treatment by other advanced oxidation process.

The wild ostrich (Struthio camelus): a review.

The aim of the current report was to study the literature pertinent to wild populations of ostriches and their ecological and behavioural adaptations in the wild. Selected areas included palaeontology; ostrich distribution; conservation status and relationships with humans and habitat. There is an immediate and urgent need to conserve and protect the apparently rapidly declining populations of wild ostriches with the committed involvement of governments and funding bodies. Wildlife management is an important complement to the farming of livestock. Scientists need to understand the elements of ostrich behaviour in the wild in order to make informed decisions on their management and contact with other animals. Information of the like should be included in readily-accessible and annually updated wildlife manuals. We deemed that such information was an essential part in the conservation of this dwindling ratite.

Enhanced electrokinetic remediation of polluted soils by anolyte pH conditioning.

In the treatment of a polluted soil, the pH has a strong impact on the development of different physicochemical processes as precipitation/dissolution, adsorption/desorption or ionic exchange. In addition, the pH determines the chemical speciation of the compounds present in the system and, consequently, it conditions the transport processes by which those compounds will move. This question has aroused great interest in the development of pH control technologies coupled to soil remediation processes. In electrokinetic remediation processes, pH has usually been controlled by catholyte pH conditioning with acid solutions, applied to cases of heavy metals pollution. However, this method is not effective with pollutants that can be dissociated in anionic species. In this context, this paper presents a study of the electrokinetic remediation of soils polluted with 2,4-Dichlorophenoxyacetic acid, a common polar pesticide, enhanced with an anolyte pH conditioning strategy. A numerical study is proposed to evaluate the effectiveness of the strategy. Several numerical tests have been carried out for NaOH solutions with different concentrations as pH conditioning fluid. The results show that the anolyte pH conditioning strategy makes it possible to control the pH of the soil and, consequently, the chemical speciation of pollutant species. Thus, it is possible to achieve an important flux of pesticide into the anolyte compartment (electro-migration of anionic species and diffusive transport of acid species). This way, it possible to maximise the pesticide accumulation in this compartment, allowing a much more effective removal of pollutants from the soil than without the anolyte pH conditioning strategy.

Scale-up of the electrokinetic fence technology for the removal of pesticides. Part II: Does size matter for removal of herbicides?

This work reports results of the application of electrokinetic fence technology in a 32 m3 -prototype which contains soil polluted with 2,4-D and oxyfluorfen, focusing on the evaluation of the mechanisms that describe the removal of these two herbicides and comparing results to those obtained in smaller plants: a pilot-scale mockup (175 L) and a lab-scale soil column (1 L). Results show that electric heating of soil (coupled with the increase in the volatility) is the key to explain the removal of pollutants in the largest scale facility while electrokinetic transport processes are the primary mechanisms that explain the removal of herbicides in the lab-scale plant. 2-D and 3-D maps of the temperature and pollutant concentrations are used in the discussion of results trying to give light about the mechanisms and about how the size of the setup can lead to different conclusions, despite the same processes are occurring in the soil.

Scale-up of the electrokinetic fence technology for the removal of pesticides. Part I: Some notes about the transport of inorganic species.

This work describes the application electrokinetic fence technology to a soil polluted with herbicides in a large prototype containing 32 m3 of soil. It compares performance in this large facility with results previously obtained in a pilot-scale mockup (175 L) and with results obtained in a lab-scale soil column (1 L), all of them operated under the same driving force: an electric field of 1.0 V cm-1. Within this wide context, this work focuses on the effect on inorganic species contained in soil and describes the main processes occurring in the prototype facility, as well as the differences observed respect to the lower scale plants. Thus, despite the same processes can be described in the three plants, important differences are observed in the evolution of the current intensity, moisture and conductivity. They can be related to the less important electroosmotic fluxes in the larger facilities and to the very different distances between electrodes, which lead to very different distribution of species and even to a very different evolution of the resulting current intensity. 2-D maps of the main species at different relevant moments of the test are discussed and important information is drawn from them. Ions depletion from soil appears as a very important problem which should be prevented if the effect of natural bioremediation and/or phytoremediation on the removal or organics aims to be accounted.

Histology Utility in Liver Graft Surveillance: What About Normal Liver Tests?

INTRODUCTION: In liver transplantation, late graft dysfunction can have several causes, particularly rejection, infection, vascular, biliary complications, and others, usually suspected by abnormal liver tests. However, normal liver tests do not confirm a normal graft and liver biopsy could identify unexpected features with repercussions in immunosuppressive therapy. The aim of this study was to determinate the histological abnormalities in patients 10 years after liver allograft transplantation with sustainably normal liver tests and evaluate the changes in immunosuppressive therapy triggered by histological data. MATERIAL AND METHODS: A retrospective analysis of liver allograft recipients was performed in an adult liver transplantation center with graft histological characterization 10 years after transplantation. Patients with abnormal liver tests and retransplantation were excluded. RESULTS: We evaluated 39 patients with repeatedly normal liver tests. Familial amyloid polyneuropathy (n = 27) was the mainly indication for liver transplantation. Allograft histological dysfunction was observed in 13 (21.7%) patients. In 3 patients we observed chronic hepatitis, signs of cellular rejection in another 3 patients, and histological features suggesting autoimmune hepatitis in 7 patients. The diagnosis of de novo autoimmune hepatitis was proposed according to contemporaneous positive autoantibodies. Changes in immunosuppressive treatment were proposed in 7 patients. CONCLUSION: Allograft histological dysfunctions 10 years after liver transplantation were observed in 21.7% of patients despite normal liver tests. Although the histological features led to alterations of immunosuppressive therapy in half of the cases, the absence of enzymatic tests changes makes monitoring a challenging process.

Electrokinetic flushing with surrounding electrode arrangements for the remediation of soils that are polluted with 2,4-D: A case study in a pilot plant.

This work aimed to evaluate electrokinetic soil flushing (EKSF) technologies for the removal of 2,4-dichlorophenoxyacetic acid (2,4-D) from spiked soils using an electrode configuration consisting of one cathode surrounded by six anodes (1c6a) and one anode surrounded by 6 cathodes (1a6c). Experiments were conducted for over one month in a bench-scale set-up (175 dm(3) of capacity) that was completely automated and operated at a constant electric field (1.0V cm(-1)). The electrical current, temperature, pH, moisture and pollutant concentration in electrolyte wells were monitored daily, and at the end of the experiments, an in-depth sectioned analysis of the complete soil section (post-mortem analysis) was conducted. Despite the geometric similarity, the two strategies led to very different results mainly in terms of water and herbicide mobilization, whereas pH and conductivity do not depend strongly on the electrode configuration. The volume of water extracted from cathodes with 1a6c is seven times higher than that of the 1c6a strategy. Herbicide was transported to the anode wells by electromigration and then dragged toward the cathode wells by electro-osmotic fluxes, with the first process being much more important. The configuration 1c6a was the most efficient and attained a transfer of 70% of the herbicide contained in the soil to flushing water in 35 days. These results outperform those obtained by the configuration 1a6c, for which less than 8% of the herbicide was transferred to flushing fluids in a much longer time (58 days).

Removal of oxyfluorfen from spiked soils using electrokinetic soil flushing with the surrounding arrangements of electrodes.

This work reports the results of a study in which the remediation of soil that undergoes an accidental discharge of oxyfluorfen is carried out by using electrokinetic soil flushing (EKSF). Two different electrode configurations were tested, consisting of several electrodes surrounding an electrode of different polarity (so-called 1A6C, one anode surrounded by six cathodes, and 1C6A, one cathode surrounded by six cathodes). A pilot plant scale was used (with a soil volume of 175dm(3)) to perform the studies. During the tests, different parameters were measured daily (flowrates, pH, electrical conductivity and herbicide concentration in different sampling positions). Furthermore, at the end of the test, a complete post-mortem analysis was carried out to obtain a 3-D map of the pollution, pH and electrical conductivity in the soil. The results demonstrate that electrode arrangement is a key factor for effective pollutant removal. In fact, the 1A6C configuration improves the removal rate by 41.3% versus the 27.0% obtained by the 1C6A configuration after a period of 35days. Finally, a bench mark comparison of this study of soil remediation polluted with 2,4-D allows for significant conclusions about the scale-up and full-scale application of this technology.

Seventh-day syndrome: a catastrophic event after liver transplantation: case report.

Seventh-day syndrome (7DS) is an early serious complication of liver transplantation, characterized by sudden failure of a previously normally functioning liver graft ∼1 week after the surgery. Although it is an uncommon event, it has major associated mortality. As its etiology is yet to be recognized, the only currently available treatment is retransplantation. We present 3 cases of orthotopic liver transplantation recipients who had an initial uneventful recovery after surgery followed by a dramatic rise of serum liver enzyme levels ∼7 days later and hepatic failure with subsequent graft loss and death despite high-dose immunosuppressive therapy. Histologic findings showed massive centrolobular hemorrhage and hepatocellular necrosis with reduced inflammation. It is essential to review and accumulate more clinical and laboratory information to better understand this syndrome and to better prevent and treat it.

Electroremediation of a natural soil polluted with phenanthrene in a pilot plant.

In this work, a pilot plant with two rows of three electrodes in semipermeable electrolyte wells was used to study the electrokinetic treatment of a natural soil polluted with phenanthrene (PHE). The electrokinetic pilot plant was an open system, i.e., there was direct contact between the soil and air. To increase the solubility of phenanthrene, thereby enhancing its transport through the soil, an aqueous solution of the anionic surfactant dodecyl sulfate was used as a flushing fluid. The results show that at the pilot scale considered, gravity and evaporation fluxes are more relevant than electrokinetic fluxes. Contrary to observations at the laboratory scale, desorption of PHE promoted by electric heating appears to be a significant removal mechanism at the pilot scale. In addition, PHE is dragged by the electroosmotic flow in the cathodic wells and by electrophoresis after interaction of the surfactant with phenanthrene in the anodic wells. In spite of the long treatment time (corresponding to an energy consumption over 500kWhm(-3)), the average removal attained was only 25%.

A case series of de novo inflammatory bowel disease after kidney transplantation.

Diarrhea, which is common after transplantation, may be due to infections and immunosuppressive therapy. Inflammatory bowel disease (IBD) de novo or as an exacerbation of pre-existent disease is a rare complication after kidney transplantation with pre-existing disease having a less aggressive clinical course than the de novo disease. Cytomegalovirus mismatch, prescription of tacrolimus instead of cyclosporine or mycophenolate mofetil rather than azathioprine as well as low-dose corticosteroid treatments have been linked to an increased incidence of IBD. This series of renal transplant recipients with de novo IBD showed a higher incidence and more aggressive course than that previously described, possibly related to increased use of tacrolimus with minimization of steroids.

New-onset lupus nephritis in a kidney transplant recipient with cystinosis-differential diagnosis with cysteamine-induced lupus: case report.

A case of lupus nephritis in an adult female kidney transplant recipient with cystinosis under cysteamine therapy is reported. Previous reports of new-onset lupus in cystinotic patients have focused in a possible relationship of lupus with cysteamine therapy, but no obvious pathophysiological association has been disclosed. The authors present a case of a 19-year-old female kidney transplant recipient with cystinosis admitted for acute allograft dysfunction, with clinical and immunologic manifestations of lupus nephritis. Cysteamine was considered as a potential cause of drug-induced lupus, and we temporarily interrupted this drug. The clinical picture, the negativity of antihistone antibodies, the nondisappearance of antinuclear antibodies after discontinuation of the drug, and the clinical stability after resuming cysteamine therapy suggested that the underlying mechanism of lupus was unrelated to the drug. This may be the first report of new-onset lupus in a kidney transplant recipient with cystinosis. Clinicians should be aware of the association of autoimmune abnormalities in patients with cystinosis.

Albúmina sérica como indicador negativo de estrés metabólico en pacientes pediátricos con sepsis: estado Anzoátegui / Serum albumin as a negative indicator of metabolic stress in pediatric patients with sepsis: Anzoategui state

Evaluar la disminución de la albúmina sérica como indicador negativo de estrés metabólico. Se estudiaron todos los pacientes pediátricos con sepsis, que ingresaron al Hospital Universitario Dr. Luis Razetti de Barcelona, Estado Anzoátegui, Venezuela, durante el período agosto a octubre 2003. Se realizaron dos determinaciones de albúmina sérica, en las primeras 48 horas (período de mayor estrés metabólico) y a los 7 a 10 días constatada la evolución satisfactoria. La muestra quedó constituida por 31 pacientes con sus controles respectivos. Disminución de las proteínas totales y la albúmina en una proporción de 2,25gr/dl y 1,75grs/dl respectivamente, P < 0,001 y P < 0,001, al compararla con los controles en las primeras 48 horas, demostrando que la albúmina es útil como indicador negativo de estrés metabólico. En el período de resolución del estrés metabólico, la albuminemia aumentó 0,85grs/dl, considerándose además a efectos de este estudio como indicador de evolución clínica favorable. Los resultados obtenidos plantean la necesidad de realizar estudios con mayor población, durante un período más prolongado, con el fin de demostrar que la albúmina puede realizarse como factor pronóstico en pacientes con estrés metabólico y que no debe dejarse sólo como simple parámetro nutricional