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951.
The lunar meteorite Sayh al Uhaymir 169 consists of an impact melt breccia extremely enriched with potassium, rare earth elements, and phosphorus [thorium, 32.7 parts per million (ppm); uranium, 8.6 ppm; potassium oxide, 0.54 weight percent], and adherent regolith. The isotope systematics of the meteorite record four lunar impact events at 3909 +/- 13 million years ago (Ma), approximately 2800 Ma, approximately 200 Ma, and <0.34 Ma, and collision with Earth sometime after 9.7 +/- 1.3 thousand years ago. With these data, we can link the impact-melt breccia to Imbrium and pinpoint the source region of the meteorite to the Lalande impact crater.  相似文献   
952.
To achieve higher titer of rabies virus higher density of host cells will need. In this study, capability of FibraCel disks packed in 500 mL spinner basket versus Cytodex-1 in 500 mL spinner flask was investigated for propagation of Vero cells and PV rabies virus proliferation. Minimal Essential Medium (MEM) + 10% Foetal Calf Serum (FCS) and Virus Production- Serum Free Medium (VP-SFM) +4 mM L-glutamine were used in growth phase and MEM+ 0.2% Bovine Serum Albumin (BSA) and VP-SFM were used in virus production phase. Adapted Vero cells grown in VP-SFM were used in all SFM experiments while batch and stepwise perfusion modes were applied and compared in growth stage. The highest Vero cell density were achieved in the trials with 10 g FibraCel disk in stepwise perfusion mode equal to 6.12 x 10(6) and 5.87 x 10(6) cells mL(-1) in MEM and VP-SFM, respectively while with 2.73 g Cytodex-1 lower density equal to 4.2 x 10(6) and 4.0 x 10(6) cells mL(-1) were achieved. The highest titer of rabies virus and overall virus production rate were resulted in VP-SFM and on 10 g disks equal to 2.9 x 10(7) Fluorescent Focus Unit (FFU) mL(-1) and 0.14 FFU/Cell/h, respectively versus 1.7 x 10(7) FFU mL(-1) and 0.08 FFU/cell/h on cytodex-1 in similar conditions. The second harvest of virus was also satisfactory in experiment with 10 g disks (1.7 x 10(7) FFU mL(-1)) in compare to Cytodex-1 (0.51 x 10(7) FFU mL(-1)). An equal surface area at 6600 and 12000 cm(-2) were provided in all comparable trials with seeding density of 12.5 x 10(3) cells cm(-2). Adapted Vero cells grown in VP-SFM were used in all SFM experiments while batch and stepwise perfusion modes were applied and compared in growth stage.  相似文献   
953.
Emiliania huxleyi is a single celled, marine phytoplankton with global distribution. As a key species for global biogeochemical cycling, a variety of strains have been amassed in various culture collections. Using a library consisting of 52 strains of E. huxleyi and an 'in house' enzyme screening program, we have assessed the functional biodiversity within this species of fundamental importance to global biogeochemical cycling, whilst at the same time determining their potential for exploitation in biocatalytic applications. Here, we describe the screening of E. huxleyi strains, as well as a coccolithovirus infected strain, for commercially relevant biocatalytic enzymes such as acid/alkali phosphodiesterase, acid/alkali phosphomonoesterase, EC1.1.1-type dehydrogenase, EC1.3.1-type dehydrogenase and carboxylesterase.  相似文献   
954.

Background:

Coronary artery disease (CAD) is a multifactorial and heterogenic disease. Recently, genome-wide association studies have reported that rs1333040 (C/T) and rs1004638 (A/T) single nucleotide polymorphisms (SNPs) in the 9p21 locus have very strong association with CAD. This study aimed to examine these associations in Southwest of Iran.

Methods:

Blood samples were collected from 200 CAD patients and 110 healthy individuals with no CAD. The association of two SNPs with CAD was evaluated by PCR and restriction fragment length polymorphism.

Results:

Chi-square test showed no association between rs1333040 SNP and CAD (X2: 4.66, df: 2, P=0.09). Also, there was no association between rs1004638 SNP and CAD (X2: 0.27, df: 2, P=0.88).

Conclusion:

No association was observed between rs1333040 and rs1004638 SNPs in the 9P21 region and CAD in Southwest of Iran. Key Words: Coronary artery disease, Single nucleotide polymorphisms, Genetic association study, Iran  相似文献   
955.
956.
An investigation on the dimensional properties of plain knitted fabric produced from cotton yarn and subjected to different relaxation treatments is presented in this paper. The main aim of this research is to characterize the internal energy of fabric by using yarn-pullout test method in ultrasonic relaxation state and compare it with other common mechanical relaxation treatments. A comprehensive experimental analysis showed that, by using ultrasonic waves, the area geometry constant value (k s) achieved was higher than the conventional relaxation methods. Then, we introduced residual-energy forming and loss-energy uniforming. The former appeared due to fabric shrinkage and the later one appeared due to release of fabric loops from extra forces which imposed during knitting process. The results also indicated that ultrasonic waves energy causes more uniformity on loop and consequently, the fabric reaches to a less internal energy than washing treatment.  相似文献   
957.
Fifty six genotypes of grain-type soybean and 17 genotypes of vegetable-type soybean collections were analyzed for protein and oil content, trypsin inhibitor, and lipoxygenase activities. The protein and oil content ranged from 36.9 to 47.9% and from 13.3 to 23.0% for different accessions in grain- and vegetable-type soybeans, respectively. Trypsin inhibitor and lipoxygenase activities ranged from 22.0 to 47.0 trypsin inhibitor units/mg meal and from 482 to 6265 lipoxygenase units/min/mg meal for grain- and vegetable-type soybeans, respectively. Significant correlations (r=–0.62 and –0.52,P<0.05) were found between protein and oil, and between protein and trypsin inhibitor. A significant positive correlation (r=0.42,P<0.05) was also calculated for oil and lipoxygenase activity. Several genotypes of soybean and vegetable soybean (plant introductions 423905, 417330, 417223, 171451, 200506, 200523, 417124, 227687, 203402, 445842, 203399, 423852, 416771, FC31927, Avoyelles, and Sooty) showed good nutritional potential and may be useful in a breeding program to improve the nutritional quality of soybean. Screening for essential amino acids, fatty acids, and trace minerals for selected genotypes is underway.  相似文献   
958.
Asthma is a common chronic disease of childhood which causes considerable morbidity. Asthma affects 1 in 13 school-age children and is a leading cause of office and emergency department visits, hospitalizations, and school absenteeism. Estimating the prevalence of asthma in the community is important in assessing the impact of asthma at the level of population. Since the pooled prevalence of asthma in Iranian elementary school age children (6-12 years old) was not identified, we decide to conduct a meta-analysis study to estimate the prevalence of asthma in elementary school age children in Iran. In order to gather the data, we searched a number of international electronic sources such as Pub Med, Embase, science direct, and ISI for English articles, and Iranian National Knowledge Infrastructure (scientific information) sources such as Iranmedx, Iran-doc, and SID for Persian articles from February 1995 to January 2010 to access the data. We used the words childhood, asthma, prevalence, and Iranian for searching relevant papers and used a data extraction form for the extracted data. The outcome in this Meta analysis study was response to the question, "Ever had asthma", based on the ISSAC program questionnaire. Eleven relevant articles were included for the Meta analysis. The pooled prevalence for girls, boys, and the two genders was obtained as 3.2% (CI; 2.5 to 3.9%), 4.3% (CI; 3.5 to 5.1%) and 3.9% (CI; 3.2 to 4.7%), respectively. The pooled prevalence of asthma in Iranian elementary school age children is low in comparison to the other reports.  相似文献   
959.
960.
Constructed wetlands have been recognized as offering a removal treatment option for high concentrations removal of chemical and biological contaminants in domestic wastewater. The enteric protozoan parasite Cryptosporidium is considered one of the highly resistant to treatment and highly infectious organisms to humans and animals. Moreover, some species of Cryptosporidium are known to have a zoonotic nature. In this investigation a pilot scale for domestic wastewater treatment system was used, consisting of the following steps in series: (1) up-flow anaerobic sludge blanket (UASB) reactor, (2) free water surface (FWS) wetland unit, and (3) sub-surface flow (SSF) wetland unit. This treatment system was fed with domestic wastewater to assess its efficiency in removing Cryptosporidium oocysts. The obtained Cryptosporidium oocysts were detected and enumerated by two different staining techniques ‘acid fast trichrome (AFT) and modified Ziehl Neelsen (MZN) stains’. Polymerase chain reaction (PCR) technique was also used to detect Cryptosporidium DNA in wastewater samples. Results revealed that anaerobic treatment (using UASB reactor) could remove about 53.1% of Cryptosporidium oocysts present in raw wastewater. The in-series connection between the two wetland units allowed complete elimination of Cryptosporidium oocysts as the first (FWS) wetland unit removed 95.9% of the oocysts present in anaerobically treated wastewater and the remaining portion of oocysts was completely removed by the second (SSF) wetland unit. Cryptosporidium oocysts were detected in 95.8% of raw wastewater samples with a mean count of 43.8 oocysts/l when AFT stain was used while they were detected in only 87.5% of raw wastewater samples with a mean count of 35.6 oocysts/l when MZN stain was used. Polymerase chain reaction (PCR) technique was able to detect Cryptosporidium DNA in only 45.8% of raw wastewater samples. Positive PCR results were only achieved in wastewater samples containing 52 oocysts or more per liter.  相似文献   
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