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1.
Artif Intell Med ; 129: 102299, 2022 07.
Article in English | MEDLINE | ID: mdl-35659386

ABSTRACT

Skin cancer is one of the dangerous types of cancer and the rate of death is increasing due to the lack of knowledge in prevention and the symptoms. It is a common cancer type around the world and it occurs when the skin cells are damaged. Hence, the detection of skin cancer near the beginning is important to prevent the spread of cancer and to increase the survival rate. Recently, image processing and machine learning techniques gained more interest in medical applications. However, early analysis of skin cancer images is very challenging due to factors, like variations in the color illumination, light reflections from the skin surface, and different sizes and shapes of lesions. To detect skin cancer at an early stage and to increase the survival rate, an effective skin cancer detection method is introduced in this study using the proposed Fractional Student Psychology Based Optimization-based Deep Q Network (FSPBO-based DQN) in the wireless network scenario. At first, the nodes simulated in the network area are allowed to capture the healthcare information to make the detection strategy using the proposed method. Then, the routing is performed by the proposed Fractional Student Psychology Based Optimization (FSPBO) algorithm by considering the fitness parameters, like distance, energy, trust, and delay. After the images (healthcare information) are reached the Base Station (BS), the pre-processing, segmentation, and cancer detection processes are carried out to detect the skin lesions. Initially, the image is fed to pre-processing phase, where a Type II Fuzzy System and cuckoo search optimization algorithm (T2FCS) filter is employed to remove the noise of images. Then, the pre-processed images are fed to the segmentation phase, where speech enhancement Generative Adversarial Network (SeGAN) is used to generate the segmented results. Afterward, the Deep Q Network (DQN) detects the skin cancer based on the segmented results, and the training of DQN is made using the proposed FSPBO algorithm, which is designed by integrating the Student Psychology Based Optimization (SPBO) and Fractional Calculus (FC). The proposed method is more robust and reduces computation time and complexity. Moreover, the proposed method achieved higher performance by considering the measures, namely accuracy, sensitivity, and specificity with the values of 92.364%, 93.20%, and 92.63%.


Subject(s)
Skin Neoplasms , Speech , Algorithms , Humans , Image Processing, Computer-Assisted/methods , Skin Neoplasms/diagnostic imaging , Students
2.
Mar Pollut Bull ; 171: 112728, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34303058

ABSTRACT

The presence of microplastics in all ecological and environmental conditions has been identified as a global problem. This article aimed to study edible salt-associated microplastics from the major salt-producing states of India. The crystal and powder salt from Tamil Nadu and Gujarat (five samples of powder salt and three samples of crystal salt from each state) were collected and analyzed for their microplastic content. The total microplastic content in the salts ranged from 46 to 115 particles per 200 g in Gujarat salt and 23 to 101 particles per 200 g in Tamil Nadu salt. The microplastics are dominated by red and blue color fibrous-shaped materials. The most common microplastics identified in the edible salts were polyethylene, polyester, and polyvinyl chloride derived from marine and salt-processing units.


Subject(s)
Microplastics , Water Pollutants, Chemical , Environmental Monitoring , India , Plastics , Water Pollutants, Chemical/analysis
3.
Foods ; 10(3)2021 Mar 18.
Article in English | MEDLINE | ID: mdl-33803809

ABSTRACT

The increasing global consumption of seafood has led to increased trade among nations, accompanied by mislabeling and fraudulent practices that have rendered authentication crucial. The multi-isotope ratio analysis is considered as applicable tool for evaluating geographical authentications but requires information and experience to select target elements such as isotopes, through a distinction method based on differences in habitat and physiology due to origin. The present study examined recombination conditions of multi-elements that facilitated geographically distinct classifications of the clams to sort out appropriate elements. Briefly, linear discriminant analysis (LDA) analysis was performed according to several combinations of five stable isotopes (carbon (δ13C), nitrogen (δ15N), oxygen (δ18O), hydrogen (δD), and sulfur (δ34S)) and two radiogenic elements (strontium (87Sr/86Sr) and neodymium (143Nd/144Nd)), and the geographical classification results of the Manila clam Ruditapes philippinarum from Democratic People's Republic of Korea (DPR Korea), Korea and China were compared. In conclusion, linear discriminant analysis (LDA) with at least four elements (C, N, O, and S) including S revealed a remarkable cluster distribution of the clams. These findings expanded the application of systematic multi-elements analyses, including stable and radiogenic isotopes, to trace the origins of R. philippinarum collected from the Korea, China, and DPR Korea.

4.
Mar Pollut Bull ; 158: 111410, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32753194

ABSTRACT

Element concentration (Fe, Mn, Pb, Zn, Cu, Cr, Ni and Co) in the surface sediments of Ashtamudi estuary, Southwest coast of India, has been analyzed to understand the spatial variation and potential ecological risk status. The sediment pollution index and Potential Ecological Risk index suggest that the northeastern part of the estuary exhibits low to moderate polluted sediments with moderate ecological risk. The results of correlation analysis indicate that the natural weathering process and river input play an important role in the distribution of the elements in the surface sediments of the estuary. The extracted factor results indicate that the fine sediment fractions supporting for accumulation of the trace elements, whereas the enriched level of Fe and Mn is chiefly controlled by the riverine process, and other elements are contributed by anthropogenic influences.


Subject(s)
Metals, Heavy/analysis , Water Pollutants, Chemical/analysis , Environmental Monitoring , Geologic Sediments , India , Lakes , Risk Assessment
5.
Cochrane Database Syst Rev ; 6: CD007935, 2017 06 20.
Article in English | MEDLINE | ID: mdl-28631816

ABSTRACT

BACKGROUND: Cognitive impairment in people with traumatic brain injury (TBI) could affect multiple facets of their daily functioning. Cognitive rehabilitation brings about clinically significant improvement in certain cognitive skills. However, it is uncertain if these improved cognitive skills lead to betterments in other key aspects of daily living. We evaluated whether cognitive rehabilitation for people with TBI improves return to work, independence in daily activities, community integration and quality of life. OBJECTIVES: To evaluate the effects of cognitive rehabilitation on return to work, independence in daily activities, community integration (occupational outcomes) and quality of life in people with traumatic brain injury, and to determine which cognitive rehabilitation strategy better achieves these outcomes. SEARCH METHODS: We searched CENTRAL (the Cochrane Library; 2017, Issue 3), MEDLINE (OvidSP), Embase (OvidSP), PsycINFO (OvidSP), and clinical trials registries up to 30 March 2017. SELECTION CRITERIA: We identified all available randomized controlled trials of cognitive rehabilitation compared with any other non-pharmacological intervention for people with TBI. We included studies that reported at least one outcome related to : return to work, independence in activities of daily living (ADL), community integration and quality of life. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials. We used standard methodological procedures expected by Cochrane. We evaluated heterogeneity among the included studies and performed meta-analysis only when we could include more than one study in a comparison. We used the online computer programme GRADEpro to assess the quality of evidence, and generate 'Summary of findings' tables. MAIN RESULTS: We included nine studies with 790 participants. Three trials (160 participants) compared cognitive rehabilitation versus no treatment, four trials (144 participants) compared cognitive rehabilitation versus conventional treatment, one trial (120 participants) compared hospital-based cognitive rehabilitation versus home programme and one trial (366 participants) compared one cognitive strategy versus another. Among the included studies, we judged three to be of low risk of bias.There was no difference between cognitive rehabilitation and no intervention in return to work (risk ratio (RR) 1.80, 95% confidence interval (CI) 0.74 to 4.39, 1 study; very low-quality evidence). There was no difference between biweekly cognitive rehabilitation for eight weeks and no treatment in community integration (Sydney Psychosocial Reintegration Scale): mean difference (MD) -2.90, 95% CI -12.57 to 6.77, 1 study; low-quality evidence). There was no difference in quality of life between cognitive rehabilitation and no intervention immediately following the 12-week intervention(MD 0.30, 95% CI -0.18 to 0.78, 1 study; low-quality evidence). No study reported effects on independence in ADL.There was no difference between cognitive rehabilitation and conventional treatment in return to work status at six months' follow-up in one study (RR 1.43, 95% CI 0.87 to 2.33; low-quality evidence); independence in ADL at three to four weeks' follow-up in two studies (standardized mean difference (SMD) -0.01, 95% CI -0.62 to 0.61; very low-quality evidence); community integration at three weeks' to six months' follow-up in three studies (Community Integration Questionnaire: MD 0.05, 95% CI -1.51 to 1.62; low-quality evidence) and quality of life at six months' follow-up in one study (Perceived Quality of Life scale: MD 6.50, 95% CI -2.57 to 15.57; moderate-quality evidence).For active duty military personnel with moderate-to-severe closed head injury, there was no difference between eight weeks of cognitive rehabilitation administered as a home programme and hospital-based cognitive rehabilitation in achieving return to work at one year' follow-up in one study (RR 0.95, 95% CI 0.85 to 1.05; moderate-quality evidence). The study did not report effects on independence in ADL, community integration or quality of life.There was no difference between one cognitive rehabilitation strategy (cognitive didactic) and another (functional experiential) for adult veterans or active duty military service personnel with moderate-to-severe TBI (one study with 366 participants and one year' follow-up) on return to work (RR 1.10, 95% CI 0.83 to 1.46; moderate-quality evidence), or on independence in ADL (RR 0.90, 95% CI 0.75 to 1.08; low-quality evidence). The study did not report effects on community integration or quality of life.None of the studies reported adverse effects of cognitive rehabilitation. AUTHORS' CONCLUSIONS: There is insufficient good-quality evidence to support the role of cognitive rehabilitation when compared to no intervention or conventional rehabilitation in improving return to work, independence in ADL, community integration or quality of life in adults with TBI. There is moderate-quality evidence that cognitive rehabilitation provided as a home programme is similar to hospital-based cognitive rehabilitation in improving return to work status among active duty military personnel with moderate-to-severe TBI. Moderate-quality evidence suggests that one cognitive rehabilitation strategy (cognitive didactic) is no better than another (functional experiential) in achieving return to work in veterans or military personnel with TBI.

6.
Ecol Evol ; 7(10): 3362-3371, 2017 05.
Article in English | MEDLINE | ID: mdl-28515872

ABSTRACT

The elemental composition (surface adsorbed and internalized fraction of Cu, Mo and P) in marine phytoplankton was first examined in cultures of the diatom Phaeodactylum tricornutum which were exposed to various levels of Cu concentrations ranging from 0.25 to 16 µmol/L with equivalent free [Cu2+] concentrations of 0.4-26 nmol/L. We observed an acceleration of algal growth rates (20-40%) with increasing ambient Cu levels, as well as slightly increased levels of internalized Cu in cells (2-13 × 10-18 mol/cell) although cellular Cu mostly accumulated onto the cell surface (>50% of the total: intracellular + surface adsorbed). In particular, we documented for the first time that the elemental composition (Mo and P) in algal cells varies dynamically in response to increased Cu levels: (1) Cellular P, predominantly in the intracellular compartment (>95%), shows with a net consumption as indicated by a gradual decrease with increasing [Cu2+] (120→50 × 10-15 mol P/cell) probably due to the fact that P, a backbone bioelement, is largely required in forming biological compartments such as cell membranes; and (2) cellular Mo, predominantly encountered in the intracellular compartment, showed up to tenfold increase in concentration in the cultures exposed to Cu, with a peak accumulation of 1.1 × 10-18 mol Mo/cell occurring in the culture exposed to [Cu2+] at 3.7 nmol/L. Such a net cellular Mo accumulation suggests that Mo might be specifically required in biological processes, probably playing a counteracting role against Cu.

7.
Mar Drugs ; 13(11): 6740-58, 2015 Nov 06.
Article in English | MEDLINE | ID: mdl-26561820

ABSTRACT

After in situ incubation at the site for a year, phytoplanktons in surface water were exposed to natural light in temperate lakes (every month); thereafter, the net production rate of photoprotective compounds (mycosporine-like amino acids, MAAs) was calculated using (13)C labeled tracer. This is the first report describing seasonal variation in the net production rate of individual MAAs in temperate lakes using a compound-specific stable isotope method. In the mid-latitude region of the Korean Peninsula, UV radiation (UVR) usually peaks from July to August. In Lake Paldang and Lake Cheongpyeong, diatoms dominated among the phytoplankton throughout the year. The relative abundance of Cyanophyceae (Anabaena spiroides) reached over 80% during July in Lake Cheongpyeong. Changes in phytoplankton abundance indicate that the phytoplankton community structure is influenced by seasonal changes in the net production rate and concentration of MAAs. Notably, particulate organic matter (POM) showed a remarkable change based on the UV intensity occurring during that period; this was because of the fact that cyanobacteria that are highly sensitive to UV irradiance dominated the community. POM cultured in Lake Paldang had the greatest shinorine (SH) production rate during October, i.e., 83.83 ± 10.47 fgC·L(-1)·h(-1). The dominance of diatoms indicated that they had a long-term response to UVR. Evaluation of POM cultured in Lake Cheongpyeong revealed that there was an increase in the net MAA production in July (when UVR reached the maximum); a substantial amount of SH, i.e., 17.62 ± 18.34 fgC·L(-1)·h(-1), was recorded during this period. Our results demonstrate that both the net production rate as well as the concentration of MAAs related to photoinduction depended on the phytoplankton community structure. In addition, seasonal changes in UVR also influenced the quantity and production of MAAs in phytoplanktons (especially Cyanophyceae).


Subject(s)
Amino Acids/metabolism , Cyanobacteria/metabolism , Diatoms/metabolism , Phytoplankton/metabolism , Carbon Isotopes , Cyanobacteria/radiation effects , Cyclohexylamines/metabolism , Diatoms/radiation effects , Glycine/analogs & derivatives , Glycine/metabolism , Lakes , Phytoplankton/radiation effects , Republic of Korea , Seasons , Time Factors , Ultraviolet Rays
8.
J Agric Food Chem ; 63(22): 5548-56, 2015 Jun 10.
Article in English | MEDLINE | ID: mdl-25980806

ABSTRACT

Mislabeling of fishery products continues to be a serious threat to the global market. Consequently, there is an urgent necessity to develop tools for authenticating and establishing their true origin. This investigation evaluates the suitability of stable isotopes and cytochrome oxidase I (COI) sequencing in identifying and tracing the origin of hairtail fish and shrimp. By use of COI sequencing, the hairtail fish samples were identified as Trichiurus japonicus and Trichiurus lepturus, while the shrimp samples were identified as Pandalus borealis, Marsupenaeus japonicus, Fenneropenaeus chinensis, Litopenaeus vannamei, Penaeus monodon, and Solenocera crassicornis. Linear discriminant analysis (LDA) of stable isotopes further categorized the individuals of the same species based on the country of origin. Natural and farmed shrimp (from the same country) were distinctly differentiated on the basis of stable isotope values. Therefore, these two methods could be cooperatively utilized to identify and authenticate fishery products, the utilization of which would enhance transparency and fair trade.


Subject(s)
Carbon Isotopes/analysis , Crustacea/genetics , Electron Transport Complex IV/genetics , Fish Proteins/genetics , Food Analysis/methods , Nitrogen Isotopes/analysis , Seafood/analysis , Sequence Analysis, DNA/methods , Animals , Crustacea/chemistry , Discriminant Analysis , Electron Transport Complex IV/analysis , Fish Products/analysis , Fish Proteins/analysis , Fishes , Geography
9.
Aquat Toxicol ; 165: 1-8, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26001085

ABSTRACT

To evaluate the effects of ultraviolet (UV) radiation on energy acquisition and consumption, the copepod Paracyclopina nana was irradiated with several doses (0-3kJ/m(2)) of UV. After UV radiation, we measured the re-brooding success, growth pattern of newly hatched nauplii, ingestion rate, and assimilation of diet. In addition, we checked the modulated patterns of DNA repair and heat shock protein (hsp) chaperoning genes of P. nana. UV-B radiation induced a significant reduction (7-87%) of the re-brooding rate of ovigerous females, indicating that UV-induced egg sac damage is closely correlated with a reduction in the hatching rate of UV-irradiated ovigerous female offspring. Using chlorophyll a and stable carbon isotope incubation experiments, we found a dose-dependent decrease (P<0.05) in food ingestion and the rate of assimilation to the body in response to UV radiation, implying that P. nana has an underlying ability to shift its balanced-energy status from growth and reproduction to DNA repair and adaptation. Also, expression of P. nana base excision repair (BER)-associated genes and hsp chaperoning genes was significantly increased in response to UV radiation in P. nana. These findings indicate that even 1kJ/m(2) of UV radiation induces a reduction in reproduction and growth patterns, alters the physiological balance and inhibits the ability to cope with UV-induced damage in P. nana.


Subject(s)
Copepoda/radiation effects , DNA Repair/genetics , Gene Expression Regulation/radiation effects , Heat-Shock Proteins/genetics , Ultraviolet Rays , Water Pollutants, Radioactive/toxicity , Animals , Copepoda/genetics , Female , Reproduction/radiation effects
10.
Environ Sci Pollut Res Int ; 22(22): 17443-52, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25382502

ABSTRACT

Accidental release of nuclides into the ocean is causing health risks to marine organisms and humans. All life forms are susceptible to gamma radiation with a high variation, depending on various physical factors such as dose, mode, and time of exposure and various biological factors such as species, vitality, age, and gender. Differences in sensitivity of gamma radiation are also associated with different efficiencies of mechanisms related to protection and repair systems. Gamma radiation may also affect various other integration levels: from gene, protein, cells and organs, population, and communities, disturbing the energy flow of food webs that will ultimately affect the structure and functioning of ecosystems. Depending on exposure levels, gamma radiation induces damages on growth and reproduction in various organisms such as zooplankton, benthos, and fish in aquatic ecosystems. In this paper, harmful effects of gamma-irradiated aquatic organisms are described and the potential of marine copepods in assessing the risk of gamma radiation is discussed with respect to physiological adverse effects that even affect the ecosystem level.


Subject(s)
Aquatic Organisms , Environmental Monitoring , Gamma Rays/adverse effects , Animals , Aquatic Organisms/physiology , Aquatic Organisms/radiation effects , Copepoda/physiology , Copepoda/radiation effects , Ecosystem
11.
Ecotoxicol Environ Saf ; 104: 51-71, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24632123

ABSTRACT

Chlorophyll a fluorescence is established as a rapid, non-intrusive technique to monitor photosynthetic performance of plants and algae, as well as to analyze their protective responses. Apart from its utility in determining the physiological status of photosynthesizers in the natural environment, chlorophyll a fluorescence-based methods are applied in ecophysiological and toxicological studies to examine the effect of environmental changes and pollutants on plants and algae (microalgae and seaweeds). Pollutants or environmental changes cause alteration of the photosynthetic capacity which could be evaluated by fluorescence kinetics. Hence, evaluating key fluorescence parameters and assessing photosynthetic performances would provide an insight regarding the probable causes of changes in photosynthetic performances. This technique quintessentially provides non-invasive determination of changes in the photosynthetic apparatus prior to the appearance of visible damage. It is reliable, economically feasible, time-saving, highly sensitive, versatile, accurate, non-invasive and portable; thereby comprising an excellent alternative for detecting pollution. The present review demonstrates the applicability of chlorophyll a fluorescence in determining photochemical responses of algae exposed to environmental toxicants (such as toxic metals and herbicides).


Subject(s)
Chlorophyll/physiology , Chlorophyta/drug effects , Environmental Pollutants/toxicity , Herbicides/toxicity , Metals/toxicity , Photosynthesis/drug effects , Chlorophyll A , Fluorescence
12.
J Indian Soc Periodontol ; 17(5): 617-23, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24174756

ABSTRACT

BACKGROUND: The ultimate goal of periodontal therapy is predictable regeneration of a functional attachment apparatus destroyed as a result of periodontitis. Reconstructive procedures have been used with varying success during the past decades to accomplish this goal. AIM: To evaluate whether the use of porous hydroxyapatite alone or a bioresorbable membrane alone would enhance the clinical results in the treatment of class II furcation defects in human lower molars. MATERIALS AND METHODS: Fifteen patients with chronic periodontitis, aged between 39 and 49 years, with a pair of similar bilateral class II furcation defects (classification of Hamp et al.) in mandibular first molars were selected. A split-mouth design was incorporated and the selected 30 furcation defects were assigned to one of the two treatment groups, i.e., Group I treated with a bioresorbable membrane from bovine-derived collagen guided tissue regeneration membrane and Group II treated using porous hydroxyapatite bone graft material on the contralateral sides. Evaluation of clinical parameters, probing depths and attachment levels, and radiographs was done preoperatively and 6 months postoperatively. RESULTS: Both the groups showed statistically significant mean reduction in probing depths and gain in clinical attachment levels and linear bone fill. Comparison between Group I and Group II showed insignificant difference. CONCLUSION: Within the limits of this study, both the treatment modalities are beneficial for the treatment of human mandibular class II furcation defects.

13.
Eur J Med Chem ; 47(1): 553-9, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22136905

ABSTRACT

One pot three-component PEG-SO(3)H catalyzed reaction of 4-(Pyridin-4-yl)benzaldehyde and triethyl phosphite with various primary amines afforded α-aminophosphonates with high yields by the Kabachnik-Field's reaction. These new structurally diversified set of α-aminophosphonates (4a-j) were evaluated for their anti-tumor activity on human chronic myeloid leukemia cells (K 562), human colon carcinoma cells (Colo 205) along with non-cancerous human embryonic kidney cells (HEK 293). They showed moderate activity on both cancerous cells and non-cancerous cells.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Chemistry Techniques, Synthetic/methods , Organophosphonates/chemical synthesis , Organophosphonates/pharmacology , Polyethylene Glycols/chemistry , Sulfonic Acids/chemistry , Antineoplastic Agents/chemistry , Catalysis , Cell Line, Tumor , Humans , Organophosphonates/chemistry
14.
Indian J Pediatr ; 77(6): 665-8, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20358315

ABSTRACT

OBJECTIVE: To ascertain the effectiveness of WHO analgesic ladder in pain management in children with leukemia. METHODS: Children with leukemia who were referred to a pain and palliative care clinic attached to the Department of Pediatrics of a medical teaching hospital during a period of 6 months were included in the study. RESULTS: Thirty nine (39) children, who constituted 64% of children on treatment for leukemia, required referral to pain and palliative care services during the study period. Of these 92% had Acute Lymphocytic Leukemia (ALL) and 8% had Acute Non Lymphocytic Leukemia (ANLL). 95% of children had nociceptive pain and 5% had neuropathic pain. Step - 1 analgesia was effective in 12 (31%) children and 21 (54%) could be managed with Step - 2 analgesia. Step - 3 analgesia was required in only 6 (15%) children. Step 3 analgesia was required in children with neuropathic pain and bone pain. CONCLUSION: WHO analgesic ladder is effective in managing pain in children with leukemia. Majority of cases of cancer pain in children could be managed by the treating physician using non-opioids, weak opioids and adjuvants as per the WHO guidelines. Children with bone pain and neuropathic pain may require referral to specialist services and use of strong opioids like morphine. The study emphasizes the need for establishing specialist pain management services in all centres where children with cancer are treated.


Subject(s)
Analgesia/methods , Analgesics/therapeutic use , Leukemia, Myeloid, Acute/complications , Pain/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/complications , Adolescent , Analgesics, Opioid/therapeutic use , Cancer Care Facilities , Child , Child, Preschool , Disease Management , Female , Guideline Adherence , Humans , Infant , Male , Pain/etiology , Pain, Intractable/drug therapy , Palliative Care/methods , Practice Guidelines as Topic , Retrospective Studies , Time Factors , Treatment Outcome , World Health Organization
15.
J Hazard Mater ; 150(3): 582-6, 2008 Feb 11.
Article in English | MEDLINE | ID: mdl-17583423

ABSTRACT

bis-[2-Hydroxy-1-naphthaldehyde] thiourea was synthesized and preconcentration cloud point extraction (CPE) for speciation determination of chromium(III) and (VI) in various environmental samples with flame atomic absorption spectrometry (FAAS) has been developed. Chromium(III) complexes with bis-[2-hydroxynaphthaldehyde] thiourea is subsequently entrapped in the surfactant micelles. After complexation of chromium(III) with reagent, the analyte was quantitatively extracted to the surfactant-rich phase in the non-ionic surfactant Triton X-100 after centrifugation. The effect of pH, concentration of chelating agent, surfactant, equilibration temperature and time on CPE was studied. The relative standard deviation was 2.13% and the limits of detection were around 0.18 microg L(-1).


Subject(s)
Chromium/analysis , Water Pollutants, Chemical/analysis , Chromium/chemistry , Environmental Monitoring , Hydrogen-Ion Concentration , Industrial Waste , Naphthalenes/chemistry , Octoxynol/chemistry , Rivers/chemistry , Spectrophotometry, Atomic/methods , Surface-Active Agents/chemistry , Temperature , Thiourea/chemistry , Viscosity , Waste Disposal, Fluid , Water Pollutants, Chemical/chemistry , Water Supply/analysis
16.
Talanta ; 71(2): 588-95, 2007 Feb 15.
Article in English | MEDLINE | ID: mdl-19071345

ABSTRACT

This article has been retracted at the request of the Editors-in-Chief. Please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). Reason: Considerable concern was raised about the research purportedly conducted at Sri Venkateswara University, India with the alleged involvement of Professor P. Chiranjeevi. Questions were raised as to the volume of publications, the actual capacity (equipment, orientation and chemicals) of the laboratory in which Professor Chiranjeevi worked, the validity of certain of the research data identified in the articles, the fact that a number of papers appear to have been plagiarized from other previously published papers, and some aspects of authorship. Professor Chiranjeevi was given the opportunity to respond to these allegations. Thereafter, a committee was constituted by the University to look into these allegations. Based on the enquiry committee report, we have been informed by the head of the Department of Chemistry at Sri Venkateswara University that the university authorities have taken disciplinary action against ProfessorChiranjeevi, as the university considers that there are grounds for such action. Therefore, based on the results of this investigation, the Editors-in-Chief are retracting this article.

17.
J Hazard Mater ; 140(1-2): 180-6, 2007 Feb 09.
Article in English | MEDLINE | ID: mdl-16872742

ABSTRACT

A Novel, rapid, sensitive and selective reactions are developed for spectrophotometric determination of trace amounts of vanadium (V) in environmental, biological, pharmaceutical and alloy samples was studied. The methods were based on interactions of 4-bromophenyl hydrazine (4-BPH) with N-(1-naphthyl ethylenediamine dihydrochloride (NEDA) in the presence of vanadium in acidic medium (acetate buffer of pH 3.0) to give violet colored derivative or on the oxidation of 4-bromophenyl hydrazine by vanadium in basic medium and coupling with chromotropic acid (CA) to yield red color derivative. The violet color derivative having an absorbance maximum at 570nm which is stable for 7 days and the red derivative with lambda(max) 495nm for 5 days. Beer's law was obeyed for vanadium in the concentration range of 0.5-6.0microgml(-1) (violet derivative) and 0.6-7.0microgml(-1) (red derivative), respectively. The optimum reaction conditions and other important analytical parameters were established to enhance the sensitivity of the proposed methods. Interference due to various non-target ions was also investigated. The proposed methods were applied to the analysis of vanadium (V) in environmental, biological, pharmaceutical and steel samples. The performance of proposed methods were evaluated in terms of Student's t-test and Variance ratio F-test that indicates the significance of proposed methods over reported method.


Subject(s)
Vanadium/analysis , Color , Environmental Pollutants/analysis , Oxidation-Reduction , Pharmaceutical Preparations/analysis , Spectrum Analysis , Steel/analysis
18.
Environ Monit Assess ; 127(1-3): 67-72, 2007 Apr.
Article in English | MEDLINE | ID: mdl-16897507

ABSTRACT

Facile, selective and sensitive spectrophotometric method has been developed for the determination of bendiocarb in its insecticidal formulations, fortified water, food grains, agriculture wastewater and agriculture soil samples with prepared reagents. The method was based on alkaline hydrolysis of the bendiocarb pesticide, and the resultant hydrolysis product of bendiocarb was coupled with 2,6-dibromo-4-methylaniline to give a yellow color product with lambda max of 457 nm or coupling with 2, 6-dibromo-4-nitroaniline to produce a red colored product with lambda max of 474 nm or coupling with 2, 4, 6-tribromoaniline to form orange red colored product has a lambda max of 465 nm. Under optimal conditions, Beer's law range for 2, 6-dibromo-4-methylaniline (DBMA) was found to be 0.6-14.0 microg mL (-1), 0.8-10.0 microg mL (-1) for 2, 6-dibromo-4-nitroaniline (DBNA) and 0.4-10.0 microg mL (-1) for 2, 4, 6-tribromoaniline (TBA). The molar absorptivity of the color systems were found to be 4.126 x 10(4) l mol (-1) cm (-1) for DBMA, 3.254 x 10(4) l mol (-1) cm (-1) for DBNA and 2.812 x 10(4) l mol (-1) cm (-1) for TBA. Sandell's of the color reactions are 0.018 microg cm (-2)(DBMA), 0.052 microg cm (-2)(DBNA) and 0.065 microg cm (-2) (TBA) respectively. The effect of the non-target species on the determination of bendiocarb was studied. The formation of colored derivatives with the coupling agents is instantaneous and stable for 18 h, 30 h, and 12 h. Performance of the proposed methods were compared statistically in terms Student's F and t-tests with the reported methods.


Subject(s)
Environmental Monitoring , Phenylcarbamates/chemistry , Spectrophotometry/methods , India , Phenylcarbamates/analysis
19.
Environ Monit Assess ; 129(1-3): 271-6, 2007 Jun.
Article in English | MEDLINE | ID: mdl-16957837

ABSTRACT

Facile, selective and sensitive spectrophotometric method has been developed for the determination of carbosulfan in insecticidal formulations, fortified water, food grains, agriculture wastewater and soil samples with newly synthesized reagents. The method was based on acid and alkaline hydrolysis of the carbosulfan pesticide, and the resultant hydrolysis product of carbosulfan was coupled with 2,6-dibromo-4-methylaniline to give a yellow color product with lambda(max) of 464 nm or interaction with 2,6-dibromo-4-nitroaniline to produce yellow colored product with lambda(max) of 408 nm or coupling with 2,4,6-tribromoaniline to form red colored product has a lambda(max) of 471 nm. Under optimal conditions, Beer's law range for 2,6-dibromo-4-methylaniline (DBMA) was found to be 0.2-12.0 microg ml(-1), 0.6-16.0 microg ml(-1) for 2,6-dibromo-4-nitroaniline (DBNA) and 0.4-15.0 microg ml(-1) for 2,4,6-tribromoaniline (TBA). The molar absorptivity of the color systems were found to be 3.112 x 10(4) l mol(-1) cm(-1) for DBMA, 3.214 x 10(4) l mol(-1) cm(-1) for DBNA and 3.881 x 10(4) l mol(-1) cm(-1) for TBA. Sandell's of the color reactions are 0.013 microg cm(-2) (DBMA), 0.012 microg cm(-2) (DBNA) and 0.011 microg cm(-2) (TBA) respectively. The effect of the non-target species on the determination of carbosulfan was studied to enhance the selectivity of the proposed methods. The formation of colored derivatives with the coupling agents is instantaneous and stable for 28, 30, and 26 h. Performance of the proposed methods were compared statistically in terms Student's F and t-tests with the reported methods.


Subject(s)
Carbamates/chemistry , Environmental Monitoring , Furans/chemistry , Insecticides , Carbamates/analysis , India , Insecticides/chemistry , Spectrophotometry
20.
Environ Monit Assess ; 128(1-3): 241-9, 2007 May.
Article in English | MEDLINE | ID: mdl-16957850

ABSTRACT

A procedure was developed for the determination of Cd, Cu, Zn, Co, Ni, Mn, Pb and Mo in water samples by inductively coupled plasma atomic emission spectrometry (ICP-AES) after preconcentration on a morpholine dithiocarbamate (mor-DTC) supported by bagasse (Saccharam aphisinaram). The sorbed elements were subsequently eluted with 4,M HNO3 and the acid eluates were analysed by ICP-AES. The influence of various parameters such as pH, flow rate of sample, eluent concentration, volume of the sample and volume of eluent were investigated to enhance the sensitivity of the present method. A 20,mL disposable syringe served as preconcentration column. Under the optimal conditions Cd, Cu, Zn, Co, Ni, Mn, Pb and Mo in aqueous sample was concentrated about 100-fold. The sorption recoveries of elements were higher than 99.6%. The method is also applied for the analysis of natural and spiked water samples.


Subject(s)
Spectrophotometry, Atomic/methods , Trace Elements/analysis , Water Pollutants, Chemical/analysis , Hydrogen-Ion Concentration , Reproducibility of Results , Sensitivity and Specificity
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