Abstract: Microbial contamination, most of which are fecal born in drinking water and food industry is a serious threat to humans. Escherichia coli is one of the most common and prevalent among them. We have developed a sensor for rapid and an early detection of contaminants, taking E.coli as a threat indicator organism. The sensor is based on co-polymerizations of aniline and formaldehyde in form of thin film over glass surface using the vacuum deposition technique. The particular doping combination of thin film with Fe-Al and Fe-Cu in different concentrations changes its non conducting properties to p- type semi conductor. This property is exploited to detect the different contaminants, believed to have the different surface charge. It was found through experiments that different microbes at same OD (0.600 at 600 nm) have different conductivity in solution. Also the doping concentration is found to be specific for attracting microbes on the basis of surface charge. This is a simple, cost effective and quick detection method which not only decreases the measurement time but also gives early warnings for highly contaminated samples.
Abstract: Due to the growth of the urban area towards lands
contaminated with ancient tails, in this work we evaluated if the
leaching with calcium thiosulfate (CaS2O3) for the recovery of silver,
gold and mercury from this soil, also dissolves arsenic, cadmium and
lead; for this, we determined their quantity per each fraction of size
of particle of the soil before and after the dissolution. Half of the soil
samples were leached in the plant Beneficiadora de Jales del Centro,
S. A. de C.V. and the rest of them remained in the laboratory. The
ICP-OES technique was used to determine the amounts of arsenic,
cadmium and lead, in the samples of both lots. The soil samples were
collected in a neighboring area at El Lampotal, Vetagrande,
Zacatecas, México, with an extension of 600 m2 at 22º52' 37.69'' N,
102º25' 11.73'' W. The amount of arsenic, cadmium and lead found
in nonleached soil and for a particle size of 47 μm was 203.72±3.73,
33.63±1.31 and 3480.99±20.4 mg/kg respectively.
Abstract: The present study attempted to improve the Mercury
(Hg) sorption capacity of kanuma volcanic ash soil (KVAS) by
impregnating the cupper (Cu). Impregnation was executed by 1 and
5% Cu powder and sorption characterization of optimum Hg
removing Cu impregnated KVAS was performed under different
operational conditions, contact time, solution pH, sorbent dosage and
Hg concentration using the batch operation studies. The 1% Cu
impregnated KVAS pronounced optimum improvement (79%) in
removing Hg from water compare to control. The present
investigation determined the equilibrium state of maximum Hg
adsorption at 6 h contact period. The adsorption revealed a pH
dependent response and pH 3.5 showed maximum sorption capacity
of Hg. Freundlich isotherm model is well fitted with the experimental
data than that of Langmuir isotherm. It can be concluded that the Cu
impregnation improves the Hg sorption capacity of KVAS and 1%
Cu impregnated KVAS could be employed as cost-effective
adsorbent media for treating Hg contaminated water.
Abstract: Organochlorine pesticides (OCPs) are known to be
persistent and bioaccumulative toxicants that may cause reproductive
impairments in wildlife as well as human. The current study uses the
snail-eating turtle Malayemys macrocephala, a long-lived animal
commonly distribute in rice field habitat in central part of Thailand,
as a sentinel to monitor OCP contamination in environment. The
nest soil, complete clutch of eggs, and blood of the turtle were
collected from agricultural areas in the Chao Phraya River Basin,
Thailand during the nesting season of 2007-2008. The novel
methods for tissue extraction by an accelerated solvent extractor
(ASE, for egg) and liquid-liquid extraction (for blood) have been
developed. The nineteen OCP residues were analyzed by gas
chromatography with micro-electron captured detector (GC-μECD).
The validated methods have met requirements of the AOAC
standard. The results indicated that significant amounts of OCPs are
still contaminated in nest soil and eggs of the turtle even though the
OCPs had been banned in this area for many years. This suggested
the potential risk to health of wildlife as well as human in the area.
Abstract: The effects of commercial or bovine yeasts on the
performance and blood variables of broiler chickens intoxicated with
aflatoxin were investigated in broilers. Four hundred eighty broilers
(Arbor Acres; 3-wk-old) were randomly assigned to 4 groups. Each
group (120 broiler chickens) was further randomly divided into 6
replicates of 20 chickens. The treatments were control diet without
additives (treatment 1), 250 ppb AFB1 (treatment 2), commercial
yeast, Saccharomyces cerevisiae, (CY 2.5 x 107 CFU/g) + 250 ppb
AFB1 (treatment 3) and bovine yeast, Saccharomyces cerevisiae,
(BY 2.5 x 107 CFU/g + 250 ppb AFB1 (treatment 4). Complete
randomized design (CRD) was used in the experiment. Feed
consumption and body weight were recorded at every five-day
period. On day 42, carcass compositions were determined from 30
birds per treatment. While chicks were sacrificed, 3-4 ml blood
sample was taken and stored frozen at (-20°C) for serum chemical
analysis to determine effects of consumption of diets on blood
chemistry (total protein, albumin, glucose, urea, cholesterol and
triglycerides). There were no significant differences in ADFI among
the treatments(P>0.05). However, BWG, FCR and mortality were
highly significantly different (P
Abstract: This study investigated the removal efficiency of electrokinetic remediation of copper-contaminated soil at different combinations of enhancement reagents used as anolyte and catholyte. Sodium hydroxide (at 0.1, 0.5, and 1.0 M concentrations) and distilled water were used as anolyte, while lactic acid (at 0.01, 0.1, and 0.5 M concentrations), ammonium citrate (also at 0.01, 0.1, and 0.5 M concentrations) and distilled water were used as catholyte. A continuous voltage application (1.0 VDC/cm) was employed for 240 hours for each experiment. The copper content of the catholyte was determined at the end of the 240-hour period. Optimization was carried out with a Response Surface Methodology - Optimal Design, including F test, and multiple comparison method, to determine which pair of anolyte-catholyte was the most significant for the removal efficiency. "1.0 M NaOH" was found to be the most significant anolyte while it was established that lactic acid was the most significant type of catholyte to be used for the most successful electrokinetic experiments. Concentrations of lactic acid should be at the range of 0.1 M to 0.5 M to achieve maximum percent removal values.
Abstract: A cross sectional study design and standard
microbiological procedures were used to determine the prevalence
and antimicrobial susceptibility patterns of Escherichia coli,
Salmonella enterica serovar typhimurium and Vibrio cholerae O1
isolated from water and two fish species Rastrineobola argentea and
Oreochromis niloticus collected from fish landing beaches and
markets in the Lake Victoria Basin of western Kenya. Out of 162
samples analyzed, 133 (82.1%) were contaminated, with S.
typhimurium as the most prevalent (49.6%), followed by E. coli
(46.6%), and lastly V. cholerae (2.8%). All the bacteria isolates were
sensitive to ciprofloxacin. E. coli isolates were resistant to ampicillin,
tetracycline, cotrimoxazole, chloramphenical and gentamicin while
S. typhimurium isolates exhibited resistance to ampicillin,
tetracycline, and cotrimoxazole. The V. cholerae O1 isolates were
resistant to tetracycline and ampicillin. The high prevalence of drug
resistant enteric bacteria in water and fish from the study region
needs public health intervention from the local government.
Abstract: Electroencephalogram (EEG) recordings are often
contaminated with ocular and muscle artifacts. In this paper, the
canonical correlation analysis (CCA) is used as blind source
separation (BSS) technique (BSS-CCA) to decompose the artifact
contaminated EEG into component signals. We combine the BSSCCA
technique with wavelet filtering approach for minimizing both
ocular and muscle artifacts simultaneously, and refer the proposed
method as wavelet enhanced BSS-CCA. In this approach, after
careful visual inspection, the muscle artifact components are
discarded and ocular artifact components are subjected to wavelet
filtering to retain high frequency cerebral information, and then clean
EEG is reconstructed. The performance of the proposed wavelet
enhanced BSS-CCA method is tested on real EEG recordings
contaminated with ocular and muscle artifacts, for which power
spectral density is used as a quantitative measure. Our results suggest
that the proposed hybrid approach minimizes ocular and muscle
artifacts effectively, minimally affecting underlying cerebral activity
in EEG recordings.
Abstract: The agriculture lignocellulosic by-products are receiving increased attention, namely in the search for filter materials that retain contaminants from water. These by-products, specifically almond and hazelnut shells are abundant in Portugal once almond and hazelnuts production is a local important activity. Hazelnut and almond shells have as main constituents lignin, cellulose and hemicelluloses, water soluble extractives and tannins. Along the adsorption of heavy metals from contaminated waters, water soluble compounds can leach from shells and have a negative impact in the environment. Usually, the chemical characterization of treated water by itself may not show environmental impact caused by the discharges when parameters obey to legal quality standards for water. Only biological systems can detect the toxic effects of the water constituents. Therefore, the evaluation of toxicity by biological tests is very important when deciding the suitability for safe water discharge or for irrigation applications.
The main purpose of the present work was to assess the potential impacts of waters after been treated for heavy metal removal by hazelnut and almond shells adsorption systems, with short term acute toxicity tests.
To conduct the study, water at pH 6 with 25 mg.L-1 of lead, was treated with 10 g of shell per litre of wastewater, for 24 hours. This procedure was followed for each bark. Afterwards the water was collected for toxicological assays; namely bacterial resistance, seed germination, Lemna minor L. test and plant grow. The effect in isolated bacteria strains was determined by disc diffusion method and the germination index of seed was evaluated using lettuce, with temperature and humidity germination control for 7 days. For aquatic higher organism, Lemnas were used with 4 days contact time with shell solutions, in controlled light and temperature. For terrestrial higher plants, biomass production was evaluated after 14 days of tomato germination had occurred in soil, with controlled humidity, light and temperature.
Toxicity tests of water treated with shells revealed in some extent effects in the tested organisms, with the test assays showing a close behaviour as the control, leading to the conclusion that its further utilization may not be considered to create a serious risk to the environment.
Abstract: There are many sources trough which the soil get
enriched and contaminated with REEs. The determination of REEs in
environmental samples has been limited because of the lack of
sensitive analytical techniques. Soil samples were collected from
four sites including open cast coal mine, natural coal burning, coal
washery and control in the coal field located in Dhanbad, India.
Total concentrations of rare earth elements (REEs) were determined
using the inductively coupled plasma atomic absorption spectrometry
in order to assess enrichment status in the coal field. Results showed
that the mean concentrations of La, Pr, Eu, Tb, Ho, and Tm in open
cast mine and natural coal burning sites were elevated compared to
the reference concentrations, while Ce, Nd, Sm, and Gd were
elevated in coal washery site. When compared to reference soil,
heavy REEs (HREEs) were enriched in open cast mines and natural
coal burning affected soils, however, the HREEs were depleted in the
coal washery sites. But, the Chondrite-normalization diagram showed
significant enrichment for light REEs (LREEs) in all the soils. High
concentration of Pr, Eu, Tb, Ho, Tm, and Lu in coal mining and coal
burning sites may pose human health risks. Factor analysis showed
that distribution and relative abundance of REEs of the coal washery
site is comparable with the control. Eventually washing or cleaning
of coal could significantly decrease the emission of REEs from coal
into the environment.
Abstract: This work involved the use of phytoremediation to
remediate an aged soil contaminated with polychlorinated biphenyls
(PCBs). At microcosm scale, tests were prepared using soil samples
that have been collected in an industrial area with a total PCBs
concentration of about 250 μg kg-1. Medicago sativa and Lolium
italicum were the species selected in this study that is used as
“feasibility test" for full scale remediation. The experiment was
carried out with the addition of a mixture of randomly methylatedbeta-
cyclodextrins (RAMEB). At the end of the experiment analysis
of soil samples showed that in general the presence of plants has led
to a higher degradation of most congeners with respect to not
vegetated soil. The two plant species efficiencies were comparable
and improved by RAMEB addition with a final reduction of total
PCBs near to 50%. With increasing the chlorination of the congeners
the removal percentage of PCBs progressively decreased.
Abstract: There has been a growing interest in utilizing surfactants in remediation processes to separate the hydrophobic volatile organic compounds (HVOCs) from aqueous solution. One attractive process is cloud point extraction (CPE), which utilizes nonionic surfactants as a separating agent. Since the surfactant cost is a key determination of the economic viability of the process, it is important that the surfactants are recycled and reused. This work aims to study the performance of the co-current vacuum stripping using a packed column for HVOCs removal from contaminated surfactant solution. Six types HVOCs are selected as contaminants. The studied surfactant is the branched secondary alcohol ethoxylates (AEs), Tergitol TMN-6 (C14H30O2). The volatility and the solubility of HVOCs in surfactant system are determined in terms of an apparent Henry’s law constant and a solubilization constant, respectively. Moreover, the HVOCs removal efficiency of vacuum stripping column is assessed in terms of percentage of HVOCs removal and the overall liquid phase volumetric mass transfer coefficient. The apparent Henry’s law constant of benzenz , toluene, and ethyl benzene were 7.00×10-5, 5.38×10-5, 3.35× 10-5 respectively. The solubilization constant of benzene, toluene, and ethyl benzene were 1.71, 2.68, 7.54 respectively. The HVOCs removal for all solute were around 90 percent.
Abstract: This work focuses on the remediation of polycyclic
aromatic hydrocarbons (PAHs)-contaminated soil via Fenton
treatment coupled with novel chelating agent (CA). The feasibility of
chelated modified Fenton (MF) treatment to promote PAH oxidation
in artificially contaminated soils was investigated in laboratory scale
batch experiments at natural pH. The effects of adding inorganic and
organic CA are discussed. Experiments using different iron catalyst
to CA ratios were conducted, resulting in hydrogen peroxide: soil:
iron: CA weight ratios that varied from 0.049: 1: 0.072: 0.008 to
0.049: 1: 0.072: 0.067. The results revealed that (1) inorganic CA
could provide much higher PAH removal efficiency and (2) most of
the proposed CAs were more efficient than commonly utilised CAs
even at mild ratio. This work highlights the potential of novel
chelating agents in maintaining a suitable environment throughout
the Fenton treatment, particularly in soils with high buffer capacity.
Abstract: In studying the possibility of using plants as
rhizoremediators, barley and grass mixture which showed resistance
to various concentrations of oil were selected. The minimum
inhibitory effect of oil on these plants by morphological parameters
such as survival of plants, length and biomass of shoot and root
compared with the control was showed. In determining physiological
parameters, a slight decrease in the number of chlorophyll a and b in
the leaves of plants was noted. The differences in the ratio of the total
surface of the roots to the work surface with the growth of plants in
soil with oil in the study of adsorption of the root surface were
showed.
Abstract: The heavy metal contamination of the technogenous
sediments and soils at the investigated dump-field show irregular
planar distribution. Also the heavy metal content in the surface water,
drainage water and in the groundwater was studied both in the dry as
well as during the rainy periods. The cementation process causes
substitution of iron by copper. Natural installation and development
of plant species was observed at the old mine waste dumps, specific
to the local chemical conditions such as low content of essential
nutrients and high content of heavy metals. The individual parts of
the plant tissues (roots, branches/stems, leaves/needles, flowers/
fruits) are contaminated by heavy metals and tissues are damaged
differently, respectively.
Abstract: Legionella pneumophila is involved in more than 95%
cases of severe atypical pneumonia. Infection is mainly by
inhalation the indoor aerosols through the water-coolant systems.
Because some Legionella strains may be viable but not culturable,
therefore, Taq polymerase, DNA amplification and semi-nested-PCR
were carried out to detect Legionella-specific 16S-rDNA sequence.
For this purpose, 1.5 litter of water samples from 77 water-coolant
system were collected from four different hospitals, two nursing
homes and one student hostel in Kerman city of Iran, each in a brand
new plastic bottle during summer season of 2006 (from April to
August). The samples were filtered in the sterile condition through
the Millipore Membrane Filter. DNA was extracted from membrane
and used for PCR to detect Legionella spp. The PCR product was
then subjected to semi-nested PCR for detection of L. pneumophila.
Out of 77 water samples that were tested by PCR, 30 (39%) were
positive for most species of Legionella. However, L. pneumophila
was detected from 14 (18.2%) water samples by semi-nested PCR.
From the above results it can be concluded that water coolant
systems of different hospitals and nursing homes in Kerman city of
Iran are highly contaminated with L. pneumophila spp. and pose
serious concern. So, we recommend avoiding such type of coolant
system in the hospitals and nursing homes.
Abstract: The performance of modified Fenton (MF) treatment
to promote PAH oxidation in artificially contaminated soil was
investigated in packed soil column with a hydrogen peroxide (H2O2)
delivery system simulating in situ injection. Soil samples were spiked
with phenanthrene (low molecular weight PAH) and fluoranthene
(high molecular weight PAH) to an initial concentration of 500
mg/kg dried soil each. The effectiveness of process parameters
H2O2/soil, iron/soil, chelating agent/soil weight ratios and reaction
time were studied using a 24 three level factorial design experiments.
Statistically significant quadratic models were developed using
Response Surface Methodology (RSM) for degrading PAHs from the
soil samples. Optimum operating condition was achieved at mild
range of H2O2/soil, iron/soil and chelating agent/soil weight ratios,
indicating cost efficient method for treating highly contaminated
lands.
Abstract: Region covariance (RC) descriptor is an effective
and efficient feature for visual tracking. Current RC-based tracking
algorithms use the whole RC matrix to track the target in video
directly. However, there exist some issues for these whole RCbased
algorithms. If some features are contaminated, the whole RC
will become unreliable, which results in lost object-tracking. In
addition, if some features are very discriminative to the
background, other features are still processed and thus reduce the
efficiency. In this paper a new robust tracking method is proposed,
in which the whole RC matrix is decomposed into several low rank
matrices. Those matrices are dynamically chosen and processed so
as to achieve a good tradeoff between discriminability and
complexity. Experimental results have shown that our method is
more robust to complex environment changes, especially either
when occlusion happens or when the background is similar to the
target compared to other RC-based methods.
Abstract: Different agricultural waste peels were assessed for
their suitability to be used as primary substrates for the
bioremediation of free cyanide (CN-) by a cyanide-degrading fungus
Aspergillus awamori isolated from cyanide containing wastewater.
The bioremediated CN- concentration were in the range of 36 to 110
mg CN-/L, with Orange (C. sinensis) > Carrot (D. carota) > Onion
(A. cepa) > Apple (M. pumila), being chosen as suitable substrates
for large scale CN- degradation processes due to: 1) the high
concentration of bioremediated CN-, 2) total reduced sugars released
into solution to sustain the biocatalyst, and 3) minimal residual NH4-
N concentration after fermentation. The bioremediation rate constants
(k) were 0.017h-1 (0h < t < 24h), with improved bioremediation rates
(0.02189h-1) observed after 24h. The averaged nitrilase activity was
~10 U/L.
Abstract: The submitted paper deals with the problems of
trapping and enriching the gases and aerosols of the substances to be
determined in the ambient atmosphere. Further, the paper is focused
on the working principle of the miniaturized portable continuous
concentrator we have designed and the possibilities of its
application in air sampling and accumulation of organic and
inorganic substances with which the air is contaminated. The stress is
laid on trapping vapours and aerosols of solid substances with the
comparatively low vapour tension such as explosive compounds.