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121.

Objective

Scandix pecten-veneris L. is a less studied wild edible herb and is considered an extinct plant species in many parts of the world. This study was designed to evaluate its phytochemical composition and biological potential of S. pecten-veneris L.

Methods

Phytochemicals including alkaloids, flavonoids, polyphenols, and tannins were determined in extracts of S. pecten-veneris. Antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), while reducing power was tested by ferric reducing/antioxidant power (FRAP) assay. Antimicrobial activity against seven bacterial and four fungal strains was evaluated using agar well diffusion assay. Enzymes inhibition study was performed for urease, phosphodiesterase-I, and catalase-II.

Results

S. pecten-veneris showed moderate antiradical activity and reducing potential of hydroxyl radicals to about 20% of the initial value. The antioxidant activity of various extracts of S. pecten-veneris showed a linear correlation with total phenolic contents in the order of water>n-butanol>chloroform>ethyl acetate>methanol extracts. S. pecten-veneris leaves showed the highest inhibitory activity against Staphylococcus aureus while the highest antifungal activity was observed against Candida albicans. The plant extract was most potent against urease enzymes but showed moderate activity against phosphodiestrase-I and carbonic anhydrase-II.

Conclusions

Our data demonstrate that in addition to its culinary uses, S. pecten-veneris has good medicinal potential and hence could be used for treating some specific health ailments.
  相似文献   
122.
Of 6634 registered industries in Pakistan, 1228 are considered to be highly polluting. The major industries include textile, pharmaceutical, chemicals (organic and inorganic), food industries, ceramics, steel, oil mills and leather tanning which spread all over four provinces, with the larger number located in Sindh and Punjab, with smaller number in North Western Frontier Province (NWFP) and Baluchistan. Hattar Industrial Estate extending over 700 acres located in Haripur district of NWFP is a new industrial estate, which has been developed with proper planning for management of industrial effluents. The major industries located in Hattar are ghee industry, chemical (sulfuric acid, synthetic fiber) industry, textile industry and pharmaceuticals industry. These industries, although developed with proper planning are discharging their effluents in the nearby natural drains and ulti- mately collected in a big drain near Wah. The farmers in the vicinity are using these effluents for growing vegetables and cereal crops due to shortage of water. In view of this discussion, there is a dire need to determine if these effluents are hazardous for soil and plant growth. So, effluents from different industries, sewage and normal tap water samples were collected and analysed for pH electrical conductivity (EC), total soluble salts (TSS), biological oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen, cations and anions and heavy metals. The effluents ofghee and textile industries are highly alkaline. EC and TSS loads of ghee and textile industries are also above the National Environmental Quality Standards (NEQS), Pakistan. All the effluents had residual sodium carbonates (RSCs), carbonates and bicarbonates in amounts that cannot be used for irrigation. Total toxic metals load in all the effluents is also above the limit i.e. 2,0 mg/L. Copper in effluents of textile and sewage, manganese in ghee industry effluents and iron contents in all the effluents were higher than NEQS. BOD and COD values of all the industries are also above the NEQS. On the whole, these effluents cannot be used for irrigation without proper treatment otherwise that may cause toxicity to soil, plants and animals as well add to the problems of salinity and sododicity. Similarly, these effluents cannot be used for fish farming.  相似文献   
123.
The study sought to determine if teachers who are taught specific communication skills designed to challenge students’ cognitive and metacognitive thinking during cooperative learning use more challenging and scaffolding behaviours to mediate students’ learning than teachers who implement cooperative learning or small-group work who have not been taught these skills. The study involved 51 teachers in three conditions (cooperative + communication conditions; cooperative condition, group-work condition) and two groups of students from each of the above teachers’ classes. The results show that the teachers in the cooperative + communication condition used significantly more challenging and scaffolding behaviours than teachers in the group-work condition but not more than the teachers in the cooperative condition. The study also showed that the children in the cooperative + communication condition provided significantly more elaborative and help-giving behaviours to group members than peers in the other two conditions and they obtained higher scores on the follow-up reasoning and problem-solving activities than their peers in the group-work condition.  相似文献   
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125.
The resonant column (RC) and cyclic triaxial (CT) devices are commonly used for the measurement of soils’ dynamic properties. The results of these tests do not agree when extrapolated to similar strain levels. The main objectives of this paper are to evaluate the effect of excitation frequency on the dynamic properties of soils, and to provide a methodology to reconcile shear modulus values obtained from RC and CT tests. The effect of frequency on the dynamic properties is evaluated using the new non-resonance (NR) method in the RC device and CT tests. Sand specimens with varying percentages of bentonite-water mixture and a clay specimen are tested. The results obtained from RC tests utilizing the NR method indicate significant change in shear modulus with frequency. The extrapolation of shear modulus from the conventional RC results to shear strains used in CT is significantly overestimated. The extrapolations improved when the results were corrected for frequency effect inferred from the NR method.  相似文献   
126.
Fibromyalgia syndrome (FMS) patients have disturbed sleep patterns which may lead to altered circadian rhythm in serum cortisol secretion. The aim of this study was to assess circadian changes, if any, in serum cortisol levels in female patients with FMS. Cortisol levels were estimated every 6 h during 24 h period; in 40 female patients satisfying ACR criteria for FMS (Age 36.4 ± 9.9), and 40 healthy females without FMS (Age 33.8 ± 11.1). A significant difference in the night time serum cortisol level was observed among the patients and control groups (patients, 12.9 ± 9.7 controls 5.8 ± 3.0; p < 0.01). However, no significant difference was found in serum cortisol levels in patients and control groups in the morning (patients, 28.4 ± 13.2 controls, 27.6 ± 14.5; p > 0.05), afternoon (patients, 14.4 ± 5.6 controls, 14.0 ± 6.6; p > 0.05) and evening hours (patients, 10.9 ± 5.8 controls, 8.9 ± 3.6; p > 0.05). It could be concluded that there is an abnormality in circadian secretion of cortisol in female FMS patients.  相似文献   
127.
Education is a human right and Fiji’s tertiary education board recently declared that all tertiary institutions in Fiji must abide by the framework in order to meet student–customers’ needs. The Fiji National University’s (FNU’s) destiny to be Fiji’s leading higher education provider could be a reality if students and staff’s expectations are considered in all decision-making processes and at all levels of management. Preliminary research was conducted on a newly proclaimed government university: the FNU. The results revealed negative quality gaps whereupon there is a high intensity of student dissatisfaction with the services provided by the FNU. FNU as a community of social and education providers needs an atmosphere to provide social and educational development at all levels to meet the social and education needs of every staff and student in order to protect the basic human rights of its staff and students, and to qualify as an education provider that is internationally acceptable.  相似文献   
128.
129.
A summary of results on synchrotron radiation is presented along with notes on its properties and applications. Quantum aspects are briefly mentioned. Synchrotron radiation facilities are described briefly with a detailed coverage of the accelerator programmes in India. Sameen Ahmed Khan did his doctoral work on the quantum theory of charged-particle beam optics at Institute of Mathematical Sciences, Chennai. He was an INFN Post-Doctoral Fellow at the University of Padova. He will be soon joining the Centro de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico.  相似文献   
130.
Recent sustainability and training and development reports have shown that banks are increasingly investing in training and development. While most banks are already utilising different forms of e-learning for certain types of training interventions and employee assessments, the focus going forward is to reinvent training within the organisation by making it more efficient, convenient, accessible and fun with educational technology. The aim of the study reported on in this article was to investigate the impact that educational technology has on training and development downtime, accessibility with regard to different learning platforms, return on investment (ROI), organisational culture and learning within the banking environment. A targeted sample of 110 respondents from 30 branches of one of the leading banks in South Africa were surveyed using a stratified random sampling approach. The study revealed that the bank has a strong organisational culture; and educational technology at the bank showed positive results with regard to decreasing downtime and seeing increased ROI.  相似文献   
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