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Zn/Al/Cl anionic clay has been synthesized by co-precipitation method and applied for adsorption of fluoride in aqueous medium. Equilibrium adsorption data were fitted to Langmuir, Freundlich, Temkin, and Generalized isotherm equations. Thermodynamic parameters like DeltaG and DeltaH values show the feasibility and exothermic nature of the adsorption process. Influence of solution pH and presence of other anions on fluoride adsorption by the clay has also been studied. Presence of carbonate in water was found to have an adverse effect on fluoride adsorption by the clay. pH(pzc) of the clay has been found to be 8.97. A two-step 1st order kinetic model was used to explain the fluoride adsorption kinetics of the as-synthesized clay. It was possible to regenerate the adsorbent with an aqueous solution of 0.01 M NaOH and the effect of regeneration on fluoride adsorption was reported up to five regeneration cycles.

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Cellulose supported layered double hydroxides (CSLDHs) were synthesized and tested for adsorption of fluoride in aqueous medium. Three samples of cellulose supported LDHs were synthesized by varying the LDH loading on cellulose. The raw cellulose, unsupported LDH and cellulose supported LDHs were characterized by XRD, SEM and BET surface area. Batch adsorption as well as fixed-bed column experiments were performed for determining the fluoride adsorption characteristics of CSLDHs. The fluoride adsorption properties of CSLDHs were found to be superior to that of reported adsorbents, including activated alumina and carbon nanotubes. Defluoridation capacity of the CSLDHs was 2-4 times higher than that of unsupported LDH. The cellulose supported LDH, CSLDH-50, having an LDH loading of 27% showed maximum fluoride uptake capacity (5.29 mg g(-1) of CSLDH, 25.18 mg g(-1) of LDH) in fixed-bed column study.

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OBJECTIVE: To determine outcomes of women with small-volume stage IB1 disease managed by conservative surgical treatment. DESIGN: A retrospective review. SETTING: The Northern Gynaecological Oncology Center, Queen Elizabeth Hospital, Gateshead, UK. POPULATION: Women with stage IB1 cervical cancer who were managed by conservative surgery over a 6-year period between 1 January 2000 and 31 December 2005. MAIN OUTCOME MEASURES: Pelvic lymph node metastases, recurrence rates and outcome survival. RESULTS: A total of 17 women with conservatively managed stage IB1 cervical cancer were identified. Their ages were 25-67 years, median 37 years, 4 women were nulliparous. All women presented with an abnormal screening smear showing at least severe dyskaryosis. Estimated tumour volumes ranged from 16 to 640 mm3, median 72 mm3. Four women showed multifocal invasion. All four nulliparous women and one parous woman underwent fertility-sparing treatment, i.e. loop cone +/- laparoscopic pelvic node dissection. The other 12 women underwent laparoscopic assisted vaginal hysterectomy/total abdominal hysterectomy +/- pelvic lymph node dissection. There were no cases of residual disease in any of the definitive treatment specimens. There were no cases of metastatic spread to pelvic lymph nodes. To date, no women have developed recurrent disease, and all women are alive and well (median follow up, 29 months). CONCLUSIONS: The conservative surgical management of small-volume stage IB1 cases in this series showed an excellent outcome with no cases showing pelvic lymph node involvement and no cases developing recurrent disease. A more formal assessment of tumour volume with a more active approach to determining the third dimension will allow more women the option of conservative treatment, thereby minimising the adverse effects of radical surgery.

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There have been no reports concerning the independent predictors of response and disease-free survival (DFS) in oral cancer in India, where the highest incidence is reported. The authors analyzed the outcome of radical radiation therapy of 378 patients with oral cancer and found that the complete response rate within 6 months of completion of treatment was 45% and the 5-year DFS was 34% (95% confidence interval 29% to 39%). Regional lymph node involvement (P less than 0.001), histologic type (P less than 0.01), and the intraoral site of lesion (P less than 0.025) were identified as independent predictors of response when adjusted in a forward stepwise logistic regression analysis. The Cox proportional hazards regression analysis revealed that regional lymph node involvement (P less than 0.001) and histologic type (P less than 0.05) were independent prognostic factors for DFS. Patients with fixed regional lymph node involvement demonstrated a relative risk (RR) of 2.4 compared with those with N0 disease. Patients with well-differentiated squamous carcinoma had an RR of 2, and those with other histologic types (other than verrucous carcinoma) had an RR of 1.5.

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Cancer is now being appreciated in India as an emerging public health problem. Approximately 600,000 new cancer cases occur in India every year, and the absolute number of new cancer patients will increase considerably, due to growth in the size of the population and an increase in the proportion of elderly persons due to improved life expectancy following control of communicable diseases. This emerging problem has received the attention of the Government of India, and some state governments within the Indian Federation have formulated National and State Cancer Control Programmes to deal with the situation. In the event of these programmes being implemented, consideration should be given now to measures of evaluation of the activities, as many of the indices, used to monitor programmes in developed countries, such as 15% reduction from peak cancer mortality, or in peak mortality from specific cancers, are not applicable in developing countries like India. Factors such as the pattern of tobacco habits in the community, knowledge, attitude and practice (KAP) patterns regarding cancer in the general population, referral practices, and the national pattern of extent of disease at presentation, gain considerable importance from the evaluation point of view. Our article mainly deals with the sources and the quality of baseline data for such factors and the realistic quantitative goals which could be set for the above factors.

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