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- Author or Editor: I. Ahmad x
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Abstract
Extensive use of chewing gums, by children in particular, entails the evaluation of trace element contents in them. Radiochemical neutron activation analysis (RNAA) was successfully employed to determine the concentration of 35 trace elements (essential, toxic and nonessential) in eight different brands of chewing gum generally consumed in Rawalpindi/Islamabad area. Comparison of trace element data of our work with literature has been presented. None of the elements detected in the brands of chewing gum examined was found to be present at a level representing a substantial contribution to the total dietary intake of the element.
Abstract
Chicken and fish have been investigated for the detection of radiation treatment using thermoluminescence (TL) technique. The samples were irradiated by 60Co gamma-source at the absorbed doses of 1, 2, 3, 4 and 5 kGy. TL response of treated and untreated samples in the temperature range of 50–300 °C was measured using TL reader with a temperature profile of 10 °C/s. The results revealed that TL values increased with temperature and maximum signal were obtained at 195 °C, in each case. It was also observed that the TL intensities enhanced with the absorbed doses (1–5 kGy) and the increase was dependent on the absorbed dose. From this study it is concluded that the TL technique is a rapid, simple and promising method for identifying chicken and fish treated with gamma-irradiation.
Abstract
Synergic solvent extraction of Pr(III), Ho(III) and Er(III) was carried out at pH
3.5 with a mixture of 2-thenoyltrifluoroacetone (HTTA) and tribenzylamine (TBA) from perchlorate media, having ionic strength 0.1M(H+, ClO
4
–
). The stoichiometmric composition of all three synergic adducts was established to be Pr(TTA)3·3TBA, Ho(TTA)3·3TBA and Er(TTA)3·3TBA. The formation constants KTTA and Ksyn and stability constant ±syn were also computed and found to be in the order Er
Ho>Pr. The effect of various anions on the extraction has also been studied.
The dynamical fluctuations of biological signals provide a unique window to construe the underlying mechanism of the biological systems in health and disease. Recent research evidences suggest that a wide class of diseases appear to degrade the biological complexity and adaptive capacity of the system. Heart rate signals are one of the most important biological signals that have widely been investigated during the last two and half decades. Recent studies suggested that heart rate signals fluctuate in a complex manner. Various entropy based complexity analysis measures have been developed for quantifying the valuable information that may be helpful for clinical monitoring and for early intervention. This study is focused on determining HRV dynamics to distinguish healthy subjects from patients with certain cardiac problems using symbolic time series analysis technique. For that purpose, we have employed recently developed threshold based symbolic entropy to cardiac inter-beat interval time series of healthy, congestive heart failure and atrial fibrillation subjects. Normalized Corrected Shannon Entropy (NCSE) was used to quantify the dynamics of heart rate signals by continuously varying threshold values. A rule based classifier was implemented for classification of different groups by selecting threshold values for the optimal separation. The findings indicated that there is reduction in the complexity of pathological subjects as compared to healthy ones at wide range of threshold values. The results also demonstrated that complexity decreased with disease severity.
Use of plant hormones as seed priming agents is known to improve the field performance especially under stressful conditions like salinity. A pot experiment was conducted to study the effects of seed priming of two wheat (Triticum aestivum L.) cultivars Auqab-2000 (salt tolerant) and MH-97 (salt sensitive) under saline (15 dS m−1) and non-saline (2.75 dS m−1) conditions. For priming seeds were soaked in aerated water (hydropriming), and solutions of kinetin (Kin; 25 mg L−1), or salicylic acid (SA; 50 mg L−1) for 12 h. All the priming treatments significantly reduced the adverse effects of salinity in terms of improving final emergence, growth and grain yield of both cultivars. Seed priming with SA and Kin improved salt tolerance in both wheat cultivars by the activation of antioxidants, i.e. superoxide dismutase (SOD) and catalase (CAT) to counterbalance the oxidative damage. Albeit, Na+ and Cl− contents increased due to salinity, all priming strategies lowered the accumulation of Na+ and enhanced the accumulation of K+ in leaves of both cultivars. The results suggest that priming with SA followed by kinetin successfully improved fitness of wheat plants exposed to salt stress.
Abstract
We report here a search for the “live” 244Pu in 1 kg deep-sea dry sediment collected in 1992 in the North Pacific. After a 546 day alpha-counting of a Pu fraction chemically separated from the alkaline-fused sediment sample at Kanazawa University, AMS analysis was performed at Hebrew University and Weizmann Institute. Only one count of 244Pu with no background ions was detected, indicating no excess over the expected stratospheric man-made fallout. A limit of 0.2 atoms of 244Pu cm−2·y−1 for extra terrestrial deposition was set under reasonable assumptions and it was then concluded from this result and the available data on interstellar medium (ISM) that the abundance of 244Pu in the ISM is less than 2·10−11 g 244Pu (g·ISM)−1. Implications of the present result are discussed.
A panel of 94 diverse hexaploid wheat accessions was used to map quantitative trait loci (QTL) underlying the yield related traits on chromosome 3A. Population structure and kinships were estimated using unlinked SSR markers from all 21 chromosomes. Analysis of variance revealed significant difference among accessions; however, genotype × year interaction was non-significant for majority of yield related traits. A mixed linear model (MLM) approach identified six QTLs for four traits that individually accounted for 10.7 to 17.3% phenotypic variability. All QTLs were consistently observed for both study years. New putative QTLs for the maximum fertile florets per spike and spike length were identified. This report on QTLs for yield related traits on chromosome 3A will extend the existing knowledge and may prove useful in marker-assisted selection (MAS) for development of high yielding cultivars.
Abstract
A new High Performance Liquid Chromatography–Photodiode Array Detector (HPLC–PDA) method has been developed for the chromatographic separation and simultaneous quantitative determination of nine bioactive compounds, i.e. four phenolic (gallic acid, ellagic acid, chebulinic acid, and tannic acid), two flavanoids (rutin and quercetin), two anthraquinones (sennoside A and B) and one oxygenated hydrocarbon (vitamin C) in a well-known Unani polyherbal formulation namely Itrifal's. Separation was accomplished on a C18 LiChrospher 100 column (5 µm, 250 × 4.6 mm) with a gradient elution and recorded at 254 nm. The results demonstrated that the proposed method is reproducible, accurate, economic, and suitable for the quality control of traditional polyherbal Unani formulations containing complex compounds with different structures such as Itrifals.
