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2.
Chemosphere ; 306: 135649, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35817183

ABSTRACT

In recent years groundwater modelling has become a major part of many projects dealing with groundwater exploitation, protection and remediation. Coimbatore city is located along the Noyyal River which is grown in size and population on either side of the river and the dumping of wastes very close to the river banks, leads to pollution of both surface and groundwater. Study on the quality of groundwater along the Noyyal River in Coimbatore city of Tamilnadu, is necessary to safeguard the interest of the people with respect to quality and quantity of water. The objective of the research is to develop Groundwater quality models to suggest ways and means to contain and remediate the polluted groundwater under various conditions. Data related to the groundwater quality, rainfall and well log were collected from the reputed government departments and fifteen sample well locations are identified near the noyyal river basin. The quality parameters such as pH, TDS, EC, TH, chlorides, alkalinity, sodium, calcium, magnesium, sulphates and nitrates are considered for the study. Groundwater quality modelling is attempted by using MODFLOW/MT3DMS with different scenarios. This study revealed that in all the scenarios the center portion of study area is more affected i.e. from P·N.Palayam to Kalangal. The groundwater flow is moving towards and along the river flow. Hence the pollutants are moving easily from upstream to the downstream side. necessary measures has to be taken to control the groundwater contamination.


Subject(s)
Groundwater , Water Pollutants, Chemical , Environmental Monitoring , Humans , Nitrates/analysis , Rivers , Water Pollutants, Chemical/analysis , Water Quality
3.
Anal Bioanal Chem ; 414(14): 4089-4102, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35426493

ABSTRACT

This work proposes a novel detection method for the ultra-sensitive colorimetric determination of lead and copper in complex water matrix. The method integrates signal amplification with analytical sensing, achieved by adsorptive preconcentration and a colorimetric assay. We report for the first time a strategic application of batch adsorption as a preconcentration method and colorimetry performed directly on the adsorbent surface enriched with metal. Commercially available kaolin was used as the adsorbent to preconcentrate the metals. The colorimetric detection of Pb and Cu was achieved using sodium rhodizonate and bathocuproine salt as chromogenic indicators, respectively. This method eliminates the involvement of complex instrumentation and the need for new sensing material preparation. The proposed method possesses high sensitivity for both Pb and Cu under optimized conditions. A linear calibration curve is obtained in two concentration ranges, spanning 1 to 100 µg L-1 with a low detection limit of 0.6 and 1.2 µg L-1 for Pb and Cu, respectively. Further, the method enables visual detection of Pb at concentrations as low as 2.5 µg L-1 by the naked eye. We demonstrate the practical applicability of the method by simultaneous detection of Pb and Cu in six different real-water samples with good apparent recovery % [90-120%]. Detection using hand-held devices indicates the feasibility for on-site analysis. Overall, this platform method offers a high scope for de-centralized monitoring of pollutants at concentrations which are prevailing in the environment. Integrating adsorptive preconcentration with colorimetric assay enables quantitative metal detection in environmental water sample matrix.


Subject(s)
Colorimetry , Water Pollutants, Chemical , Adsorption , Colorimetry/methods , Copper/analysis , Lead , Water , Water Pollutants, Chemical/analysis
4.
Water Sci Technol ; 84(10-11): 2635-2651, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34850682

ABSTRACT

In this research, the thermodynamic (energy and exergy) analysis of a single slope solar still using graphite plates and block magnets (GPBMSS) was investigated during summer and winter climatic conditions of Coimbatore city (latitude: 11°01'68''N and longitude: 76°95'58''E), in India, 2019. The results observed in GPBMSS were compared with a conventional solar still (CSS) under the same climatic conditions. The outcomes observed that the hourly productivity in GPBMSS was 19.6% and 22.8% higher in summer and winter days, respectively, when compared to CSS. The cumulative productivity in GPBMSS was found to be about 3.93 kg/m2 and 3.56 kg/m2 respectively, for 12 h observations during summer and winter days. Furthermore, the energy and exergy efficiencies of GPBMSS were substantially improved by 20.6% and 18.1% when compared to CSS during summer days. Similarly, the energy and exergy efficiencies of GPBMSS were increased by 18 and 19% compared to CSS in winter days. In addition, the maximum basin exergy destruction was observed in CSS compared to other solar still components. The results observed that the heat storage ability of the graphite plates and water magnetization in GPBMSS greatly decreased the exergy destructions. Finally, the water quality analysis proved that the distillate collected from both GPBMSS and CSS satisfied the requirements recommended by the Bureau of Indian Standards.


Subject(s)
Graphite , Hot Temperature , Magnets , Seasons , Sunlight
5.
Clin Exp Dermatol ; 34(2): 136-9, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18828847

ABSTRACT

BACKGROUND: High rates of fusidic acid (FA)-resistant Staphylococcus aureus (FRSA) in patients with skin disease have been previously attributed to high usage of topical FA. AIMS: To assess whether local community guidelines to restrict topical FA has affected its prescription and use and the level of FRSA in patients with skin disease. METHODS: Stapylococcus aureus isolates from microbiology samples received over a 4-month period in 2004 were tested for antibiotic sensitivities. Comparison was then made with the results of a previous study carried out in 2001. RESULTS: A significant fall was seen in the use of topical FA in dermatology patients. In 2001, 62% of patients had used FA-containing preparations within the previous 6 months, compared with just 15% of patients in 2004 (P < 0.001). The number of topical FA prescriptions in primary and secondary care dropped between 2001 and 2004. The proportion of S. aureus isolates resistant to FA in dermatology patients had not significantly fallen between 2001 (50%) and 2004 (41%) (P = 0.4). However, there was a significant increase in FA resistance within hospital inpatients, nondermatology outpatients and primary-care patients (P < 0.05). The FRSA level had doubled in hospital inpatients (20%) and almost tripled in nondermatology outpatients (28%) and primary care patients (25%). CONCLUSION: Persistent high levels of FA resistance may represent the development of an FRSA reservoir in the community. Continued restriction of FA is still recommended.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Dermatitis, Atopic/drug therapy , Fusidic Acid/therapeutic use , Staphylococcal Skin Infections/drug therapy , Staphylococcus aureus/drug effects , Administration, Topical , Dermatitis, Atopic/microbiology , Drug Resistance, Bacterial , Female , Humans , Male , Practice Guidelines as Topic , Prevalence , Retrospective Studies , Staphylococcal Skin Infections/microbiology , Staphylococcus aureus/isolation & purification
7.
Br J Dermatol ; 148(5): 1018-20, 2003 May.
Article in English | MEDLINE | ID: mdl-12786835

ABSTRACT

BACKGROUND: Antibiotic resistance is a significant problem both in hospitals and the community. Topical antibiotics are widely used for dermatological problems and this may be leading to the emergence of resistant bacteria. OBJECTIVE: To assess the level of fusidic acid-resistant Staphylococcus aureus inpatients with dermatological problems. METHODS: All microbiology samples over a 4-month period were tested for antibiotic sensitivities. Patients with cultures positive for S. aureus were studied. RESULTS: The study shows 50% of S. aureus isolates from dermatology patients were resistant to fusidic acid. This figure rose to 78% inpatients with atopic eczema. Of patients with fusidic acid-resistant S. aureus isolates, 96% had used a fusidic acid-containing preparation within the previous 6 months. The level of fusidic acid resistance in S. aureus samples cultured from nondermatology patients was only 9.6%, a level significantly below that for dermatology patients (P < 0.001). CONCLUSIONS: High levels of fusidic acid-resistant S. aureus are found in dermatology patients. Inappropriate use of topical antibiotics in dermatology patients leading to fusidic acid resistance may threaten the efficacy of systemic fusidic acid for the treatment of serious S. aureus infections. Education of health professionals and restriction of the use of fusidic acid is needed.


Subject(s)
Anti-Bacterial Agents , Dermatology , Drug Resistance, Bacterial , Fusidic Acid , Hospital Departments , Staphylococcus aureus/isolation & purification , Administration, Topical , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Prevalence , Skin Diseases/drug therapy , Skin Diseases/microbiology
8.
J Rheumatol ; 28(1): 102-8, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11196509

ABSTRACT

OBJECTIVE: To study risk factors for low bone mineral density (BMD, g/cm) in patients with systemic lupus erythematosus (SLE). METHODS: Ninety-two consecutive patients with SLE followed by rheumatology faculty between 1997 and 1999 completed a questionnaire regarding lifestyle during the clinic visit, a chart review was performed, and data were collected for the time of the first dual energy x-ray absorptiometry (DXA) examination. Univariate and multivariate statistical analyses were used to assess relationships between various risk factors and BMD. RESULTS: Ninety-eight percent of patients had received prednisone, 51% were postmenopausal (9 of whom received hormone replacement therapy), 68% had received hydroxychloroquine, and 15% were osteoporotic. The following factors were found to be significantly related to lower BMD by univariate analysis: Caucasian race, older age at diagnosis, higher age at the time of the first DXA, longer disease duration, higher cumulative corticosteroid dose, higher SLE Damage Index score, and postmenopausal status. In the multivariate analysis only the following factors were significant: Caucasian race, increased number of pregnancies, postmenopausal status, higher SLE Damage Index, and higher cumulative corticosteroid dose. An unexpected finding was that taking hydroxychloroquine was the only factor associated with higher BMD of the hip and spine in the univariate analysis, and it remained predictive of higher BMD of the hip and spine in the multivariate analysis. CONCLUSION: Hydroxychloroquine appears to protect against low BMD in corticosteroid treated patients with SLE.


Subject(s)
Bone Density/physiology , Lupus Erythematosus, Systemic/epidemiology , Osteoporosis, Postmenopausal/epidemiology , Absorptiometry, Photon , Activities of Daily Living , Adolescent , Adult , Aged , Child , Connecticut/epidemiology , Estrogen Replacement Therapy/adverse effects , Female , Femur Neck/diagnostic imaging , Humans , Hydroxychloroquine/therapeutic use , Lumbar Vertebrae/diagnostic imaging , Lupus Erythematosus, Systemic/complications , Lupus Erythematosus, Systemic/drug therapy , Lupus Erythematosus, Systemic/metabolism , Middle Aged , Osteoporosis, Postmenopausal/drug therapy , Osteoporosis, Postmenopausal/etiology , Osteoporosis, Postmenopausal/metabolism , Postmenopause , Prednisone/therapeutic use , Risk Factors , Severity of Illness Index , Surveys and Questionnaires
9.
J Hosp Infect ; 33(1): 55-61, 1996 May.
Article in English | MEDLINE | ID: mdl-8738202

ABSTRACT

A three month prospective audit of wound infection following emergency and elective caesarean section was carried out in five West Yorkshire hospitals. Among 4076 women undergoing delivery in the five obstetric departments, the caesarean rate was 15.4%. The overall infection rate was 45/628 (7.2%) with a range of 2.5-17.2% between the five centres. The infection rate was 14/226 (6.2%) when antibiotics were used compared with 31/402 (7.7%) without antibiotics. The use of prophylactic antibiotics made no significant difference to the infection rate, which did not correlate with duration of labour or of ruptured membranes. The number of vaginal examinations correlated with the infection rate. In conclusion, the caesarean section rate observed was higher than that estimated for the UK as a whole, but was distorted by one centre with a high rate. For the other four hospitals the caesarean rate was unexceptional. The ratio of emergency to elective operations was comparable with recently reported values in the UK and the wound infection rate was within the widely varying limits found in previous studies. In view of the relatively low infection rate recorded without antibiotics, in the interests of cost effectiveness, prophylaxis may be limited in future to selected women at high risk. Because this was an audit rather than a randomized study we cannot exclude that this is already happening on an empirical basis.


Subject(s)
Cesarean Section/adverse effects , Medical Audit , Surgical Wound Infection/prevention & control , Antibiotic Prophylaxis , Chi-Square Distribution , England , Female , Humans , Linear Models , Pregnancy , Prospective Studies
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