Validating models of one-way land change: an example case of forest insect disturbance     

Harati  Saeed  Perez  Liliana  Molowny-Horas  Roberto  Pontius  Robert Gilmore 《Landscape Ecology》2021,36(10):2919-2935

Landscape Ecology - Validation of models of Land Use and Cover Change often involves comparing maps of simulated and reference change. The interpretation of differences between simulated and...  相似文献   

Genetic variation of Rutilus rutilus caspicus (Jakowlew 1870) populations in Iran based on random amplified polymorphic DNA markers: a preliminary study     

Saeed Keyvanshokooh  & Mohammad Reza Kalbassi 《Aquaculture Research》2006,37(14):1437-1440

Rutilus rutilus caspicus is regarded as a valuable fish species both for angling and commercial food in Iran. This fish is also considered as a significant food source for beluga sturgeon. The genetic diversity of this fish species collected from two geographical areas (Gorgan Bay and Anzali Wetland) along the Iranian coastline of the Caspian Sea was examined using the analysis of randomly amplified polymorphic DNA (RAPD). Using 10 decamer primers, the total number of RAPD bands produced in both Gorgan Bay and Anzali Wetland populations were 94 bands. The percentages of polymorphic bands were comparable in Anzali Wetland (41.48%) and Gorgan Bay (43.61%), suggesting similar levels of polymorphism of the two populations to be used for establishing selective breeding programmes. The value of Nei's genetic distance (d=0.04) among populations was small, despite the large geographic separation. The data serve as a baseline analysis of current genetic diversity found among R. rutilus caspicus populations in Iran.  相似文献   

Genetic diversity of Pakistan wheat germplasm as revealed by RAPD markers     

Iftikhar?Ahmad Khan  Faisal?Saeed AwanEmail author  Aftab?Ahmad  Yong-Bi?Fu  Ahsan?Iqbal 《Genetic Resources and Crop Evolution》2005,52(3):239-244

Wheat breeding in Pakistan started in 1930s before partition in the United India and so far has released more than 68 cultivars, but no systematic analyses of the genetic diversity of Pakistan wheat have been made. Twenty Pakistan wheat cultivars released from 1933 to 2002 were examined for genetic diversity and relationships using random amplified polymorphic DNA (RAPD) markers. Forty-two RAPD primers were applied and 184 polymorphic bands were generated for each cultivar. Most of the cultivars were genetically interrelated, although six of them displayed some genetic distinctness. The RAPD variation observed among these cultivars was low. Only 40.7% of the total scorable bands were polymorphic, and 26.1% of the polymorphic bands were observed most frequently (f = 0.95) among the 20 cultivars. The proportions of polymorphic bands for each cultivar ranged from 0.67 in ‘Yecora’ to 0.84 in ‘C-250’ with an average of 0.76. About 1.4% of the RAPD variation might have been fixed over the 69 years of wheat breeding, but such fixation was not statistically significant. These results are significant for future improvement and conservation of Pakistan wheat.  相似文献   

Prevalence of subclinical ketosis in dairy cattle in the Southwestern Iran and detection of cutoff point for NEFA and glucose concentrations for diagnosis of subclinical ketosis   总被引：1，自引：0，他引：1  

Asl AN  Nazifi S  Ghasrodashti AR  Olyaee A 《Preventive veterinary medicine》2011,100(1):38-43

Subclinical ketosis (SCK) is simply a condition marked by increased levels of circulating ketone bodies without the presence of the clinical signs of ketosis. Subclinical ketosis can cause economic losses through decreased milk production and association with preparturient diseases. Limited information is available regarding the prevalence of SCK in dairy herds in Southwestern Iran. The objectives of this study were (i) determination of the cutoff point of nonesterified fatty acids (NEFAs) and glucose concentrations for diagnosis of SCK using receiver operating characteristic (ROC) analysis, and (ii) determination of prevalence of subclinical ketosis in apparently healthy dairy cattle in Southwestern Iran. From October to December 2009, a total of 100 clinically healthy multiparous Holstein cows (3-8 years old) were randomly selected from 16 dairy herds around Kazerun, Fars Province, Iran. The cows had two-six lactations, with body weight ranging from 500 to 650 kg. Blood samples for each cow were taken at 2, 4 and 6 weeks post parturition and 3-4h after the morning feeding. The optimal cutoff point was set, by the ROC method, to >0.26 mmol/L for NEFA, and < 2.26 mmol/L for glucose with corresponding 82.54% sensitivity and 91.89% specificity for NEFA and 44.44% sensitivity and 78.38% specificity for glucose. Cows with BHB concentrations higher than 1200 μmol/L were classified as having SCK. In 2, 4 and 6 weeks post parturition 63%, 68% and 59% of the tested cows were subclinically ketotic. Overall, 97% of tested cows (97/100) were considered subclinically ketotic in at least one sample period. Thirty percent of tested cows (30/100) suffered from subclinical ketosis in all of the 2, 4 and 6 weeks postpartum. The results suggest that, a cut-off point of 0.26 mmol/L for NEFA concentrations can be used during early lactation for diagnosis of subclinical ketosis and making management decisions for prevention and treatment. Glucose cannot be a good criterion for diagnosis of SCK and it does not appear to be useful for monitoring subclinical ketosis.  相似文献   

Monitoring Nitrogen Dioxide Levels in Urban Areas in Rawalpindi, Pakistan     

Sheikh Saeed Ahmad  Patrick Biiker  Lisa Emberson  Rabia Shabbir 《Water, air, and soil pollution》2011,220(1-4):141-150

Nitrogen dioxide is an important gaseous air pollutant. It plays a major role in atmospheric chemistry, particularly in the formation of secondary air pollutants, and contributes to environmental acidification. A comprehensive assessment of NO₂ levels in the atmosphere is required for developing effective strategies for control of air pollution and air quality improvement. Air pollution is a serious problem in all major cities of Pakistan and needs to be addressed to minimize detrimental effects on human health and urban vegetation. In this research, we focused on the monitoring of NO₂ levels in the urban environment of Rawalpindi city. Because of the lack of expensive continuous sampling devices and to get a good spatial coverage of the NO₂ concentrations in the study area, NO₂ passive samplers were exposed at 42 different sites within the city limits of Rawalpindi from January to December, 2008. Samplers were exchanged every 10 days and the associated meteorological conditions like temperature, wind speed, rainfall and relative humidity were also monitored. The average NO₂ concentration was found to be 27.46?±?0.32 ppb. The highest values of NO₂ were measured near to main roads and educational institutions due to intense flow of road vehicles. Moreover, the study showed that the values obtained for NO₂ for all sampling points exceeded the annual limit value set by World Health Organization. So, this is very important to take different steps to control this before it becomes a serious hazard for people living in those areas.  相似文献   

Bluetongue virus seropositivity in sheep flocks in North West Frontier Province, Pakistan     

Saeed Akhtar  Nakiri Djallem  Gul Shad  Olaf Thieme 《Preventive veterinary medicine》1997,29(4):293-298

The objectives of this study were to describe the prevalence and distribution of serum antibodies to Bluetongue virus (BTV) in a sample of 38 sheep flocks in northern areas of the North West Frontier Province of Pakistan and to identify demographic and productivity variables that are associated with BTV seropositivity. Blood samples were taken from a random sample of ewes in each flock in April 1995. The owners of the flocks were interviewed regarding some demographic, husbandry and productivity variables of the flocks on the day of blood sampling. A competitive enzyme-linked immunosorbent assay was conducted to test the serum samples for BTV group-specific antibodies. BTV seropositive reactions were obtained in 184 (48.4%) out of 380 tested sera, and in 89.5% (34/38) of the flocks. In the 34 seropositive flocks, the prevalences ranged from 12.5 to 100% (median = 47). A multivariable logistic analysis was carried out to study the influence of demographic and productivity variables on the BTV serological status of the sheep flocks. Abortion risk in the previous lambing season was mildly associated with the serological status of the flock (adjusted odds ratio = 1.16, P = 0.07). For the seropositive flocks, a linear multiple regression showed that distance travelled by the flock during transhumant movement was significantly associated with percent seropositivity (partial regression coefficient (± SE) = − 0.091 ± 0.045).  相似文献   

Antibacterial activity of Caesalpinia bonducella seeds.     

M A Saeed  A W Sabir 《Fitoterapia》2001,72(7):807-809

The methanol extract and four triterpenoids isolated from the seeds of Caesalpinia bonducella showed a wide range of inhibiting activity against both gram-positive and gram-negative bacteria.  相似文献   

Mutualistic fungus Piriformospora indica modulates cadmium phytoremediation properties of host plant via concerted action of enzymatic and non-enzymatic biochemicals     

Muhammad KHALID  Saeed UR-RAHMAN  Haoxin TAN  Lantian SU  Pei ZHOU  Nan HUI 《土壤圈》2022,32(2):256-267

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Study on Fruitset and Pollen-Compatibility Status in Sweet Cherry (Prunus avuim L.) Cultivars     

Piri  Saeed  Kiani  Esmaiel  Sedaghathoor  Shahram 《Erwerbs-Obstbau》2022,64(2):165-170

Prunus avium L. is one of the most important temperate zone fruits in the world. Most of the cherry cultivars always have difficulties of fertilization and fruit set due to self-incompatibility, so they need suitable and compatible pollinizers for commercial fruit production. In this experiment, pollination compatibility of cherry cultivars of ‘Napoleon’, ‘Burlat’, ‘Zhan’, and ‘Lambert’ was studied as both pollen recipients and donors. To determine the compatibility or incompatibility of pollinizers, percent of fruit set was calculated. This research was carried out as a factorial experiment in a randomized complete block design. The final average fruit set in studied cultivars was different under self or cross-pollination. The results showed that ‘Napoleon’, ‘Zhan’ and ‘Lambert’ cultivars are the suitable pollinizers for ‘Burlat’. Also, ‘Burlat’ is a cultivar which produced many fruits under self-pollination. Therefore, ‘Burlat’ can be used as monoculture for orchard establishment. Results showed that cultivar ‘Napoleon’ was cross-incompatible with ‘Lambert’. ‘Zhan’, ‘Napoleon’ and ‘Lambert’ cultivars are founded self-incompatible and require cross-pollinations to obtain fruits.

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Shift work as an oxidative stressor     

Akbar?SharifianEmail author  Saeed?Farahani  Parvin?Pasalar  Marjan?Gharavi  Omid?Aminian 《Journal of circadian rhythms》2005,3(1):15

Background  

Some medical disorders have higher prevalence in shift workers than others. This study was designed to evaluate the effect of night-shift-working on total plasma antioxidant capacity, with respect to the causative role of oxidative stress in induction of some of these disorders.  相似文献