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Khan S.,University of Peshawar | Asif Khan M.,Karakorum International University
Journal of Earth System Science | Year: 2016

Soft sediments make an important component of the subsurface lithology, especially in areas underlain by river/stream basins. Occupying a position directly above the bedrock up to the land surface, these soft sediments can range in thickness from few centimeters to hundreds of meters. They carry a special nuisance in seismic hazards, as they serve as a source of seismic amplification that may enhance the seismic shaking of many folds. Determination of the thickness of the soft sediments is therefore crucial in seismic hazard analysis. A number of studies in recent years have demonstrated that frequency and amplitude spectrum obtained from the noise measurements during the recording of natural seismicity can be used to obtain thickness of soft sediments covering the bedrock. Nakamura (1989) presented a technique to determine such spectrum using ratio of horizontal to vertical components of the Rayleigh waves. The present study is based on an extensive set of microtremor measurements carried out in the Islamabad city, Pakistan. Fundamental frequencies were obtained from weak motion sensors and Tromino Engy Plus instruments to show that the correlation is clearly valid for a wide range of sediment thickness. A simple formula was derived for the investigated area to determine directly the thickness of sediments from the main peaks in the H/V spectrum for seismometer and Tromino data separately. A comparison is made between sediment thicknesses derived from empirical relations developed in this study with those given in literature to demonstrate a positive correlation. The correlation of instrumental resonant frequencies with calculated resonant frequencies (theoretical) suggests that the relation derived from the noise measurements mostly depends on the velocity depth function of the shear wave. The fundamental frequency of the main peak of spectral ratio of H/V using the both instruments correlates well with the thickness of sediments at the site obtained from the borehole data. It is found out that there is a wide variation in soft-sediment thickness in the Islamabad area, but as a general rule, soft sediments are thicker adjacent to stream courses compared to the areas intervening the streams. The distribution of sediments in the studied area is illustrated by means of cross sections constructed from results of the microtremor analyses and available borehole data, which provides a visual distribution of the soft sediments underlying the Islamabad city. © Indian Academy of Sciences.

Khan T.,Karakorum International University | Khan I.A.,Karakoram International University | Rehman A.,Karakoram International University | Ali S.,Karakoram International University | Ali H.,Karakoram International University
Life Science Journal | Year: 2014

Berberis, a member of family Berberidaceae serves as 'wildlife-clinic' in nature. Berberis pseudumbellata subsp. gilgitica is endemic to the area and has become critically endangered. For the first time research documented unique epigenetic behaviour of different mountain wildlife and zoopharmacological practices of traditional communities from CKNP. When wildlife gets physical hurts, it rushes towards Berberis plants and eat berries, chew leaves or bark, which is found significant (p<0.001). Such behaviour is untaught, not learned, and automatic but seems pre-programmed instinctively triggered reflexed. This is observed in avifauna (House Sparrow, Chakor, Ram Chakor) and angulates (Flare horned Markhor, Himalayan Ibex) only. 79.03%, 36.51% hunters (SD±30.02), 83.24%, 58.23% shepherds (SD±17.68) and 41.92%, 17.11% local population (SD±17.54) believe and have personal observations respectively for Berberis-wildpharma interaction. Traditionally it is used zoopharmacologically for bone healing of limbs (93.67%), other bone fracture and injury (90.91%), other internal injuries (85.53%), external injuries (73.33%), delivery of sheep (38.12%), goat (17.36%) and cow (19.87%). No such observation was recorded with respect to herpetofauna and carnivores.

Wasim M.,Pakistan Institute of Nuclear Science and Technology | Ali M.,Karakorum International University | Iqbal S.,Pakistan Institute of Nuclear Science and Technology
Journal of Radioanalytical and Nuclear Chemistry | Year: 2015

The Northern Areas of Pakistan is known for its relatively higher radioactivity level. No study has been conducted for Nagar, which is located at 2,590 m above sea level (ASL) and Shigar at 2,300 m ASL. Soil samples were collected from the two cities and gamma-emitting radionuclides were assayed using gamma-ray spectrometry. The average activity concentrations, average air absorbed dose rate, average annual effective dose and three hazard indices namely the radium equivalent activity, external hazard index and internal hazard index were calculated. The risk to human was estimated using the excess life-time cancer risk for people living in the two cities. © 2014, Akadémiai Kiadó, Budapest, Hungary.

Shah S.,Dalian University of Technology | Shah S.,Karakorum International University | Hao C.,Dalian University of Technology
Environmental Science and Pollution Research | Year: 2016

Sulfonamide antibiotics (SAs) have been observed to undergo direct and indirect photodegradation in natural water environments. In this study, the density functional theory (DFT) method was employed for the study of direct and indirect photodegradation mechanisms of sulfameter (SME) with excited triplet states of dissolved organic matter (3DOM*) and metal ions. SME was adopted as a representative of SAs, and SO2 extrusion product was obtained with different energy paths in the triplet-sensitized photodegradation of the neutral (SME0) and the anionic (SME−) form of SME. The selected divalent metal ions (Ca2+, Mg2+, and Zn2+) promoted the triplet-sensitized photodegradation of SME0 but showed an inhibitory effect in triplet-sensitized photodegradation of SME−. The triplet-sensitized indirect photodegradation mechanism of SME was investigated with the three DOM analogues, i.e., 2-acetonaphthone (2-AN), fluorenone (FN), and thioxanthone (TN). Results indicated that the selected DOM analogues are highly responsible for the photodegradation via attacking on amine moiety of SME. According to the natural bond orbital (NBO) analysis, the triplet-sensitized photodegradation mechanism of SME0 with 2-AN, FN, and TN was H-transfer, and the SME− was proton plus electron transfer with these DOM analogues. © 2016 Springer-Verlag Berlin Heidelberg

Noor A.,University of Karachi | Khatoon S.,University of Karachi | Ahmed M.,University of Karachi | Razaq A.,Karakorum International University
Bangladesh Journal of Botany | Year: 2014

In Astore valley, 26 species of plants under 17 genera and 13 families were found to be used as folkmedicine. The study reveals that the villagers from remote area use medicinal plants for the treatment of joint pain, bone fracture, urine problem, asthma, diabetes, blood pressure and for the treatment of other common ailments. The aborigines also use traditional herbal therapy for their live stocks. Because of high destruction pressure of anthropogenic origin, Ephedra gerardiana Wallich ex C.A.Meyer, Berberis spp., Rosa foetida Herrm. and Rhododendron hypenanthum Balf. f. were found threatened.

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