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        Application of modified cloud point extraction method for the chromium speciation in artificial saliva extracts of different snuff products

        Asma Akhtar,Tasneem Gul Kazi,Hassan Imran Afridi,Mustafa Khan,Muhammad Bilal,Noman Khan 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.59 No.-

        A modified cloud point extraction method (m-CPE) was developed for the speciation of chromium species (Cr3+ and Cr6+) in artificial saliva extracts (ASE) of snuff products. In this method, Cr3+ was complexed with 8-hydroxyquinoline, which was trapped in nonionic surfactant (Triton X-114), prior to analyzed by electrothermal atomic absorption spectrometer (ETAAS). Whereas, the total extractable Cr was determined by reducing Cr6+ to Cr3+ using Na2SO3 as a reducing reagent. Several parameters were optimized for the developed m-CPE. Under the most favorable conditions, enrichment factor, enhancement factor and limit of detection for the proposed method were 60, 134 and 0.04 μg L−1, respectively having relative standard deviation <5%. Health risks associated with the intake of total Cr in snuff products was also assessed. Estimated daily intake of Cr via sniffing 10 g/day of dry and moist snuff products was found below the maximum tolerable daily intake whereas the calculated risk for cancer due to Cr was observed in the acceptable range of 10 E−6–E−4.

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        Dielectric and impedance studies of DBSA doped polyaniline/PVC composites

        Asma B. Afzal,M. Javed Akhtar,Muhammad Nadeem,M.M. Hassan 한국물리학회 2010 Current Applied Physics Vol.10 No.2

        Polyaniline (PANI) was doped with dodecylbenzene sulfonic acid (DBSA) and then mixed with PVC by solution blending method to prepare DBSA doped PANI (PAND)/PVC composites. FTIR spectroscopy indicates the strong dipole–dipole interaction between the individual components of the composites. The ac electrical properties of the synthesized composites were investigated by complex impedance spectroscopy in the frequency range of 0.5–106 Hz at room temperature. Both dielectric loss factor and permittivity increase with the decrease of frequency exhibiting strong interfacial polarization at low frequency. Addition of PAND in PVC reduces the charge trapping centers by increasing the number of conducting channels participating in the relaxation process; hence an increase in conductivity is observed.

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        Morphological characterization and biological control of Alitropus typus (Isopoda: Aegidae)

        Syed Aizaz Ali SHAH,Asma ASHRAF,Naveeda-Akhtar Qureshi 한국곤충학회 2017 Entomological Research Vol.47 No.6

        The Alitropus typus infestation has a serious influence on fish farming in Pakistan. The present study focuses on the external morphology and control of highly infested ectoparasitic isopod Alitropus typus. Sixteen morphological parameters of the whole body were measured and statistically analyzed for mean, standard error and coefficient of variation by using the student t test. Non‐significant variations were observed in the size of pereopods which depict the significance of swimming and attached to its host. For biological control, different concentrations (1000, 5000 and 10 000 ppm) of a leaf extract of four plants (i.e. Euphorbia helioscopia, Ajuga bracteosa, Cannabis sativa and Callistemon citrinus) were tested against A. typus, and the mortality rates were recorded after 12, 24 and 36 h. One way Anova and Tukey tests were used to analyze the results. The recorded percentage mortality was in the order of E. helioscopia > A. bracteosa > C. sativa, whereas C. citrinus did not showed any toxicity. Concentrations of biochemical components like carbohydrates (mg/g), proteins (mg/g), and lipids (mg/dL) of treated isopods were estimated by the phenol‐sulfuric acid process, Lowry's method and biochemistry analyzer, respectively. The protein contents of the insects tested had decreased markedly as compared to control rates, and this might be due to insecticidal stress caused by the extracts. In another biocontrol experiment, crabs were introduced along with isopods into an aquarium. It was then noted that one crab consumes an average of seven isopods/week and can act as a scavenger for dead organisms.

      • Threshold Primary Tumour Sizes for Nodal and Distant Metastases in Papillary and Follicular Thyroid Cancers

        Zaman, Maseeh Uz,Fatima, Nosheen,Sajjad, Zafar,Akhtar, Jaweed,Islam, Najmul,Masood, Qamar,Ahmed, Asma Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.6

        Background: In papillary and follicular thyroid cancers (PTC, FTC), nodal and distant metastasis are generally considered important determinants of recurrence and survival, respectively. However, there is no consensus about the threshold primary tumour size (PTS) for these determinants. The aim of this study was to assess size relationships for developing nodal, pulmonary, bone and overall distant metastases. Methods: This prospective study covered 139 (93 females and 46 males) consecutive biopsy proven patients with PTC (114/139, mean age $41.0{\pm}15.7$ years, M: F, 35%:65%) and FTC (25/139, mean age $39.2{\pm}14.3$ years, M: F: 24%:76%). Results: Average primary tumor size was $23.4{\pm}11.1$ mm and $26.5{\pm}13.1$ mm for PTC and FTC respectively (p value=0.223). Nodal metastasis was found more common in PTC than FTC (49% vs 28%, p value <0.05), whereas overall distant metastasis was approximately the same (13% and 24%, p value=0.277); however, bone metastasis was significantly higher in FTC than PTC (24% vs 5%, p value <0.05). Cumulative risk for nodal and distant metastases for FTC and PTC starts at PTS <20 mm and may indicate an unusual aggressive tumor behavior in the studied population. Highest cumulative risk for nodal and pulmonary metastases in PTC and for bone metastasis in FTC was found to be ${\geq}50$ mm PTS. Conclusion: We conclude that a PTS of <20 mm may indicate an unusual aggressive tumor behavior with highest cumulative risk for nodal and pulmonary metastases in PTC and for bone metastasis in FTC with a cutoff of ${\geq}50$ mm.

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