3,109 research outputs found
Alternative low-cost adsorbent for water and wastewater decontamination derived from eggshellwaste: an overview
As the current global trend towards more stringent environmental standards, technical applicability and cost-effectiveness became key factors in the selection of adsorbents for water and wastewater treatment. Recently, various low-cost adsorbents derived from agricultural waste, industrial by-products or natural materials, have been intensively investigated. In this respect, the eggshells from egg-breaking operations constitute significant waste disposal problems for the food industry, so the development of value-added by-products from this waste is to be welcomed. The egg processing industry is very competitive, with low profit margins due to global competition and cheap imports. Additionally, the costs associated with the egg shell disposal (mainly on landfill sites) are significant, and expected to continue increasing as landfill taxes increase. The aim of the present review is to provide an overview on the development of low-cost adsorbents derived from eggshell by-products
Removal of hexavalent chromium of contaminated soil by coupling electrokinetic remediation and permeable reactive biobarriers
PURPOSE:
In this study, a novel and ecological alternative have been developed to treat soils contaminated with hexavalent chromium coupling two well-known systems: electrokinetic remediation and permeable reactive biobarriers. The electric field promotes the electromigration of the hexavalent chromium oxyanions towards the anode. The biobarriers were placed before the anode electrode, in order to promote the reduction and retention of the chromium migrating in its direction. Thus, this technology provided a global treatment to soil removal without subsequent treatments of the contaminated effluents.
METHODS:
The electrokinetic system was coupled with two different permeable reactive biobarriers composed by Arthrobacter viscosus bacteria, supported either in activated carbon or zeolite. An electric field of 10 V was applied and two different treatment times of 9 and 18 days were tested.
RESULTS:
Removal values of 60% and 79% were obtained when electrokinetic treatment was coupled with zeolite and activated carbon biobarriers, respectively, for a test period of 18 day. The reduction of hexavalent chromium to trivalent chromium was around 45% for both systems.
CONCLUSIONS:
In this work, two types of biobarriers were efficiently coupled to electrokinetic treatment to decontaminate soil with Cr(VI). Furthermore, the viability of the new coupling technology developed (electrokinetic + biobarriers) to treat low-permeability polluted soils was demonstrated.This work was supported by the Spanish Ministry of Science and Innovation (CTQ2008-03059/PPQ), Xunta de Galicia (08MDS034314PR). The authors are grateful to the Spanish Ministry of Science and Innovation for providing financial support for Marta Pazos under the Ramon y Cajal program and the Fundacao para a Ciencia e Tecnologia, Ministerio da Ciencia e Tecnologia, Portugal through the PhD grant of Bruna Fonseca (SFRH/BD/27780/2006)
Grad’s Moment Equations for Binary Hard Sphere Gas-Mixtures
This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.The derivation of non-linear Grad’s 2×26-moment (2×G26) equations for a binary gasmixture
of monatomic-inert-ideal hard sphere gases is sketched, although—for conciseness—only the
linear 2×G26 equations are illustrated and analysed. The linear stability analysis is performed on
2×G26 equations by studying the dispersion relation and by considering the plane wave solution, it is
shown that the 2×G26 equations for binary hard sphere gas-mixture are linearly stable
Analysis of genetic variation in different banana (Musa species) variety using random amplified polymorphic DNAs (RAPDs)
The banana (Musa acuminata Colla) is considered as an important crop plant due to its high economic value as good dietary source. Here, we analyze the genetic relationship of four different banana varieties that are cultivated in south India. Random amplified polymorphic DNAs (RAPDs) fingerprinting of these banana varieties (Grand Naine, Red Banana, Nendran and Rasthali) carried out by three primers (OPA-19, OPB-18, OPD-16) led to DNA amplification. 43.47% of the amplification products weremonomorphic (common to all the genotypes), whereas 30.43% were unique, but only 26.08% revealed the relationship between these genotypes
Laparoscopic management of common bile duct stones: Our experience
INTRODUCTION: Common Bile Duct stones (CBD) are found in approximately
16% of the patients undergoing Laparoscopic cholecystectomy (LC). Till
recently, the gold standard for treating CBD stones was endoscopic
removal, if that failed, then open surgery. However, in the
laparoscopic era, the best treatment for CBD stones is a matter of
debate and it continues to evolve. The objective of the present study
is to determine that laparoscopic CBD exploration (LCBDE) is a safe,
feasible and single-stage option for the management of CBD stones.
MATERIALS AND METHODS: Out of the 2900 laparoscopic cholecystectomies
between 1998-2004 we did selective intraoperative cholangiogram in 262
patients who were suspected to have CBD stones based on deranged liver
function tests, dilated CBD with or without CBD stone on sonography or
having the history of recent jaundice / pancreatitis. If CBD stone was
found, either a transcystic or transcholedochal exploration was done
depending on the size, site, number of stones and CBD diameter.
Choledochotomy was closed over a t-tube in the majority of the
patients. Primary closure of CBD was done in few patients and in one
patient we placed an antegrade stent and in another we placed
endoscopic stent into the CBD laparoscpically which was removed after
four weeks. RESULTS: Till date we have performed LCBDE in 64 patients.
Transcystic exploration was done in 14 patients and transcholedochal
exploration was done in 46 cases out of which 2 patients had minor
biliary leak which settled on conservative treatment in 2-3 days. Four
patients required conversion to open surgery as there were multiple
stones. We did not have any major complication and on 6 months
follow-up in 76% patients, none was found to have residual stone.
CONCLUSION: The treatment of CBD stones depends on the resources
available, technical limitations and the surgeon's expertise.
Laparoscopic CBD exploration is a safe, feasible and single-stage
option for the management of CBD stones
Dynamic changes in biochemical markers of renal function with thyroid status- A study in Indian population
Thyroid dysfunction is known to cause significant changes in glomerular filtration rate. The present cross-sectional study was performed to evaluate the changes in biochemical markers of renal function in hypothyroid subjects before and after treatment. Thyroid function tests (T3, T4 and TSH levels) were assayed in 385 subjects. Based on TSH levels, subjects were classified as euthyroid (n=198), sub-clinical hypothyroid (n=98; TSH 6.1 to 19.9 μIU/ml) and overt hypothyroid (n=89; TSH ≥ 20 μIU/ml, abnormally low T4 levels). Forty-eight hypothyroid patients were re-evaluated after 3 months of thyroxine replacement therapy. Renal function tests were carried out in all subjects and statistically analyzed. Serum creatinine was significantly increased in subclinical and overt hypothyroid groups as compared to euthyroid subjects. Serum creatinine showed a significant negative correlation with T3 &T4 levels in overt group(r = -0.372 and r = - 0.371), whereas a positive correlation was observed with TSH (r=0.283). Uric acid levels were significantly increased in the overt group as compared to euthyroid subjects. Uric acid levels showed a significant negative correlation with T3 levels in the overt group (r= -0.298). After 3 months of thyroxine replacement therapy, creatinine and uric acids levels decreased significantly and were comparable to euthyroid levels. Hypothyroidism leads to reversible changes in renal function
Systemic antibody response to Chlamydia Trachomatis infection in patients either infected or reinfected with different Chlamydia serovars
© 2017 Indian Journal of Medical Microbiology | Published by Wolters Kluwer - Medknow. Introduction: Chlamydia trachomatis is the etiological agent for the most prevalent bacterial sexually transmitted infection in both developed and developing countries. The aim of present study was to characterize the antibody response between two groups of individuals, having either a single C. trachomatis infection and or repeated infections. Material and Methods: Current study consisted of two groups, one with an initial Chlamydia infection and a second with repeated infections. A titre based estimation of specific serum (IgG and IgA) levels using ELISA were performed, which further validated by western blot. In vitro neutralizing ability of each patient's serum against both homologous and heterologous strains was also determined. Results: Individuals infected with one of the C. trachomatis serovars D, E or K exhibited a strong systemic antibody response as characterized by ELISA and western blot. These individuals may have developed at least some level of protection as they only represented single infection. By comparison, individuals infected with serovar D, E or F that exhibited low systemic antibody response often presented repeated C. trachomatis infections, suggesting an association with poor immune response. An in vitro neutralizing level of 60-90% was observed in the human sera against homologous serovar D and two heterologous C. trachomatis serovars E and K, compared to <40% against heterologous serovars F. Conclusion: Individuals infected with serovars D and K showed a potential association between circulating antibody response and re-infection risk. While the patients infected with serovars E showed a disconnection between systemic antibody response and re-infection risk
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