1,222 research outputs found

    Dynamic Compaction in Assalouyeh, Iran

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    Dynamic compaction used as a soil improvement method for treatment of filled material in sea in Assalouyeh, Iran. Land reclamation by filling soil performed up to depth 14m and dynamic compaction used for reduction of liquefaction potential and the settlements due to static loadings. The compaction pattern and the other parameters like applied energy, compaction phases and rest periods designed in term of the characteristics of the soil to be treated and filling material deep. Final compaction pattern revised according to the results of the compaction on trial areas. Extensive trial compactions performed to optimize the compaction process with respect to the required energy for achieving specified densification criterion. Dynamic compaction carried out in two and three passes. Using 16 patterns (combination of weight of pounder, falling height and the arrangement of the impact points) the 90 hectares area improved in 12 months. For testing of efficiency of dynamic compaction geotechnical site investigation tests performed before and after compaction. The desired tests were measurement of induced settlement, boring and Standard Penetration test, Plate load test and Field density test. The results of tests showed that the dynamic compaction was useful to increase bearing capacity up to 3 kg/cm2 for shallow foundations and reduced mostly liquefaction potential

    Toxicity of various silver nanoparticles compared to silver ions in the Ponto-Caspian amphipod Pontogammarus maeoticus (Sowinsky, 1894)

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    According to the increased probability of the presence of nanomaterials in the aquatic ecosystems, the present study examined the toxicity of three engineered silver nanoparticles (AgNPs) as well as silver ions in the Pontogammarus maeoticus, a brackish water benthic organism living in the littoral zone of the Caspian Sea. The animals were acutely exposed to different concentrations of two commercially prepared colloidal forms and a freshly prepared suspension of silver nanoparticles, plus AgNO3 during 48 hr. The number of mortalities was assessed and lethal concentration values were calculated using the EPA Probit Analysis Program. According to median lethal concentrations (LC50), the order of sensitivity of this amphipod to tested silver compounds was as: previously prepared AgNPs colloids > freshly prepared AgNPs suspension > AgNO3. Also the signs of nanoparticle accumulation were evident between the pereopods and pleopods of this gammarid; this accumulation could be one of the reasons for the higher toxicity of silver nanoparticles in comparison with silver ions in P. maeoticus. More acute and chronic studies are needed to understand the various aspects of nano-silver toxicity on amphipods in different salinities

    Toxicity comparison of silver nanoparticles synthesized by physical and chemical methods to tadpole (Rana ridibunda)

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    One of the possible threats in increasing use of nanomaterials is the emergence of toxicity in humans and other animals which is discussed in nanotoxicology. In addition to toxic effects of nanomaterials themselves, different chemical precursors which are usually used in bottom-up approaches for production of nanomaterials may have secondary toxic effects in living organisms. In contrast, less use of chemicals in top-down approaches may reduce these secondary effects. To test this hypothesis, toxic effects of two types of silver nanoparticles (AgNPs) produced by physical (top-down) and chemical (bottom-up) methods were investigated and compared on the tadpole, Rana ridibunda survival. The estimated 48 h LC50 values of AgNPs produced by chemical and physical methods for tadpoles were 0.055 ± 0.004 and 0.296 ± 0.085 mg.L-1, respectively. No observed effect concentration, lowest observed effect concentration, maximum acceptable toxicant concentration and median lethal concentration of AgNPs produced by chemical method were respectively 3.42, 4.50, 4.84 and 5.38 times less than those produced by physical method. Therefore, approving the mentioned hypothesis, it was revealed that AgNPs produced by chemical method are more toxic than those generated by physical method. However, it seems totally that AgNPs regardless of the method used for their production, have toxic effects on aquatic organisms and so, inhibiting their accidental or intentional entrance into the aquatic ecosystems should be more considered

    Karyological study of the medicinal plant Papaver rhoeas from northwest of Iran

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    Karyotype and morphology of mitotic chromosomes in six populations of the medicinal plant Papaver rhoeas collected from various geographical locations of the northwest of Iran were studied. Chromosome characteristics were measured from 10 complete metaphase cells using micromeasure software. The results showed that P. rhoeas is a diploid species with 2n=2x=14 chromosomes. The karyotype consisted of seven pairs of submetacentric chromosomes with one pairs of SAT chromosome (chromosome 2) having a secondary constriction at the end of its short arm. Karyological characteristics of all the materials studied were similar to each other; however, there were some variations on chromosome arm ratios and relative lengths among the different populations. All of the populations are placed on 4A class of Stebbin’s asymmetry categories.Key words: Biodiversity, chromosome analysis, medicinal plants, Papaveraceae

    A comparative assessment of the effects of fresh and saltwater on soluble proteins and surimi made from Hypophthalmichthys molitrix

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    Due to the special taste of the Silver carp, the fish is not used for production of Surimi. Researchers have shown that water soluble proteins in water and brine have significant effects on the taste, flavor and odor of the Surimi produced from the fish. In this study, the effects of washing minced meat of Silver carp with fresh water and brine with 1.5 and 2.5 percent salt for 5, 10 and 15 minutes on the taste of Surimi and its shelf life cold stored for 120 days were investigated. We prepared three lots of minced meat from silver carp and each lot was washed with fresh water and brine with 1.5 and 2.5 percent salt, for 5, 10 and 15 minutes. The extracted water soluble proteins from fresh water washing were 1.3, 2.7, and 4.01 and for brine were 2, 4.2, 6.3 and 2.96 5.92 and 9 percent of the total protein of the fish for 1.5% and 2.5% salt respectively. A taste panel ranked the Surimi made from minced meat after washing with 1.5% brine for 10 minutes as the best in terms of taste, flavor and odor. We recorded a change in protein content of the Surimi made from minced meat washed with fresh water and be and stored for 120 days at -18°C, from 17.02 to 16.46, 14.73 to 13.5 and 12.03 to 11.5%, respectively. TVN for the same samples were increased from 9.76 to 13.2, 8.43 to 12.10 and 7.03 to 1 Img/100g. Changes in peroxide value were zero to 1.9, zero to 1, and zero to 0.8 Milli-equivalents/1000g. The total count of the bacteria for these Surimi samples were between 15 to zero colonies after 120 days storage at 48 C. Data from the different chemical, microbial, and sensory quality measurement were subjected to one way Anova and Ducan's multiple range test and the results showed a significant difference between the treatments at P<0.05. For production of Surimi from washing minced meat of silver carp is better to wash minced meat with 1.5% brine for 10 minutes. The Surimi's nutrition rate including: Protein 16.83%; fat 2.2%; moisture 82.65% and ash 1.5%

    Efficient design and evaluation of countermeasures against fault attacks using formal verification

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    This paper presents a formal verification framework and tool that evaluates the robustness of software countermeasures against fault-injection attacks. By modeling reference assembly code and its protected variant as automata, the framework can generate a set of equations for an SMT solver, the solutions of which represent possible attack paths. Using the tool we developed, we evaluated the robustness of state-of-the-art countermeasures against fault injection attacks. Based on insights gathered from this evaluation, we analyze any remaining weaknesses and propose applications of these countermeasures that are more robust

    Final Report: Water-Based Neutron Detector Technology for Material Characterization Well Counters

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    Low density lipoprotein cholesterol control status among Canadians at risk for cardiovascular disease: findings from the Canadian Primary Care Sentinel Surveillance Network Database

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    Background To determine the prevalence of uncontrolled LDL-C in patients with high cardiovascular disease (CVD) risks across Canada and to examine its related factors. Methods Non-pregnant adults >20 years-old, who had a lipid test completed between January 1, 2009 and December 31, 2011 and were included in the Canadian Primary Care Surveillance Network (CPCSSN) database were studied. The Framingham-Risk-Score was calculated to determine the risk levels. A serum LDL-C level of >2.0 mmol/L was considered as being poorly controlled. Patients with a previous record of a cerebrovascular accident, peripheral artery disease, or an ischemic heart disease were regarded as those under secondary prevention. Logistic regression modeling was performed to examine the factors associated with the LDL-C control. Results A total of 6,405 high-risk patients were included in the study and, of this population, 68 % had a suboptimal LDL-C, which was significantly associated with the female gender (OR: 3.26; 95 % CI: 2.63–4.05, p < 0.0001) and no medication therapy (OR: 6.31, 95 % CI: 5.21–7.65, p < 0.0001). Those with comorbidities of diabetes, hypertension, obesity, and smokers had a better LDL-C control. Rural residents (OR: 0.64, 95 % CI: 0.52–0.78, p < 0.0001), and those under secondary prevention (OR: 0.42; 95 % CI: 0.35–0.51, p < 0.0001), were also more likely to have a better LDL-C control. Conclusion A high proportion of high-cardiac risk patients in Canadian primary care settings have suboptimal LDL-C control. A lack of medication therapy appears to be the major contributing factor to this situation

    Domestic violence and suicide attempt among married women: A case‐control study

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    The aim of this study was to investigate the impact of domestic violence‐related factors on suicide attempt in married women. Suicide is a global public health concern that poses significant burden on individuals, families and communities. There is limited research on factors predicting suicide attempt in women. A retrospective case‐control design was adopted. Using a convenience sampling method, 610 participants, admitted to a teaching referral hospital in Northwest of XXX, were recruited to the study and assigned to case or control groups based on whether or not they had attempted suicide. The participants in two groups were matched in the terms of important demographic characteristics. Domestic violence‐related factors were considered as independent variables and suicide attempt as dependent variable. Descriptive statistics, simple and multivariate logistic regression analysis were used to analyze the data. Odd ratios (OR) of domestic violence related factors were compared between the groups. We used STROBE checklist as an EQUATOR in this study. The mean age of participants in the case and control groups was 28.4 years and 29.45 years, respectively. The infidelity was the strongest predictor of suicide attempt in women (OR 44.57, 95%CI 6.08‐326. 63, p<0.001), followed by being threatened to physical assault by husband (OR 37.01, 95%CI 11.54‐118.67, p<0.001), jealousy of husband (OR 23.46, 95%CI 11.63‐47.30, p<0.001), and previous attempts to divorce (OR 16.55, 95%CI 5.91‐46.31, p<0.001). Suicide attempt was significantly lower in women who reported a sense of peace in life or lived with their mother or father‐in‐law (p<0.001). To reduce the risk of suicide in women, violence against women should be condemned and appropriate prevention measures be taken by health professionals. Recognizing risk, assessment and referral of victims of domestic violence should be an integral part of health care systems.N/
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