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Biological and ecological studies of water resources play an important role in both researches and scientific studies. The most important step for this study is identifying the characteristics of the ecosystem, living organisms and environmental factors. In recent years, Water quality evaluation, especially drinkable water, became both important and essential for reduction in quality and quantity of them. Lakes and ponds always being under attention as the most important resources for drinking and agricultural purposes. To improve efficiency of uses of the water resources, we need appropriate methods to determine quality of them. Investigate the quality of the Zayandeh roud lake water as an important resource to supplying drinking and agricultural water, in its basin and other province is necessary. In this study after determining 5 stations in different parts of the lake, sampling was done one time per every 45 days. WQI index calculated with use of 6 parameters: No2, No3, DO, EC, Hardness and, pH. However, despite of decreasing of the water quality of zayandeh roud lake, but according to WQI index, water of the lake was in the good category (50-100). This study was also showed that the water quality of zayandeh roud lake need a comprehensive management.

The Choghakhor International Wetland plays an important role in preserving and protection of part of the plant and animal species in the Iranian plateau. Since the water of this wetland is utilized for different human purposes, complete periodic chemical and physical quality assessment of its water seems necessary. Water quality index (WQI) was calculated using the following eleven parameters: Nitrate, Nitrite, Ammonium, Alkalinity, Hardness, Turbidity, Conductivity, Dissolved Oxygen, Total Dissolved Solid, pH and Biochemical Oxygen Demand (BOD5). For this purpose, the relative weight assigned to each parameter ranged from 1 to 4 based on the importance of the parameter for aquatic environment and human health. The analyses of variance (ANOVA) of data revealed significant differences between different periods of sampling (p

Este artigo compara as características dos problemas de aritmética utilizados nos exames de admissão ao ginásio, entre 1930 e 1960, e as características de um Bom Problema defendidas, em especial, por Edward Lee Thorndike. Apresenta resultados obtidos a partir da pesquisa de mestrado intitulada “A resolução de problemas de aritmética no Ensino Primário: um estudo das mudanças no ideário pedagógico (1920-1940)”. Em relação à metodologia, utilizou-se do ferramental produzido por historiadores da História Cultural, em especial os conceitos de Apropriação, Prática e Representação, propostos por Roger Chartier. As fontes utilizadas foram exames de admissão ao ginásio aplicados pelo Ginásio do Estado, em São Paulo, entre as décadas de 1930 até 1960, bem como manuais para o ensino de aritmética que estiveram em circulação no estado no mesmo período. A análise indica uma mudança significativa na representação do que seria um Problema, passando a distinguir questões de aplicação imediata de cálculo aritmético de Problemas. Percebe-se, ainda, uma apropriação e incorporação gradativa das características de um Bom Problema, tal como defendiam intelectuais ligados ao movimento Escola Nova: Realidade, Utilidade e Interesse.

The effects of using n-3 LC-PUFA -enriched Artemia nauplii and newly hatched Artemia on survival and resistance to pH stress in larvae of angel fish (Peterophylum scalar) were examined In tow 20 days period. In the first step of the experiment the larvae with an average weight of 0.86 ±0.03mg were fed with tow diets (enriched Artemia nauplii and newly hatched Artemia) for 20 days. At the end of the first step of the experiment, the significantly (p

The effect of five different diets consisting of green algae Scenedesmus quadricauda, cereal plant meal (wheat+white+canola+barley), fish food meal, mixed manure powder (chicken manure+cattle manure), and baker's yeast (Saccharomyces cerevisiae) were investigated on fecundity rate, larval development time and body length in freshwater copepod Eucyclops serrulatus. A complete randomized design was employed using an individual gravid female in 50ml vials at 26ºC water temperature. The maximum fecundity was obtained in copepods fed on fish diet (18.6±1.08, eggs /female; mean±SD) followed in order by baker's yeast (17.3±3.19), cereal plant meal (13±2.45), Scenedesmus (9.3±0.41), and mixed manure powder (8.6±0.82). The larval developmental time of copepod E. serrulatus was significantly different in copepods fed on examined diets. The mean shortest naupliar time (8.3±0.81 days) and copepodit time (1.0±0.70 days) were observed in copepods fed on fish food meal with a significant difference compared to other examined treatments. In addition, length and width of naupliar, copepodit, and adult of copepod E. serrulatus increased when copepods fed on fish diet and baker's yeast.

The effect of garlic essential oil (garlic essence) as an growth promoter, on growth, feeding indices and chemical body composition were investigated in juveniles of reared beluga (Huso huso). Six diets (one diet without garlic essential oil and antibiotic as in control diet, one diet with 30 mg/kg Oxytetracycline antibiotic and four diets with 50, 100, 150 and 200 mg/kg garlic essence) were prepared. Juveniles of reared beluga with averaged weight 24±1.50 g were fed with these diets for 8 weeks. The Final Weight (FW) and percentage increase in Body Weight (BWI), Protein Efficiency Ratio (PER), Protein Production Ratio (PPR) and Protein level of Chemical body composition wear significantly higher in diet with 150 mg/kg garlic essences while, the Food Conversion Ratio (FCR) was significantly lower. This treatment was significantly (P

In this study, effects of five different diets including green algae, Scenedesmus quadricauda, mixture of S. quadricauda and baker's yeast, cattle manure, poultry manure, mixture manure (cattle + poultry, 1:1 ratio in weight) were examined on density, specific growth rate and doubling time of freshwater Cladoceran, Ceriodaphnia quadrangula population, at two high and low levels of food density with three replications. The results showed that the maximum population density (184 individuals/50ml), maximum specific growth rate (SGR) (0.18/day) and minimum doubling time (Dt) (3.85 days) were obtained when C. quadrangula fed with S. quadricauda at high density (50×104 cell/ml). In addition, the minimum population density (7.3 ind/50 ml), minimum SGR (0.019 /day), and maximum Dt (36.2 days) resulted from C. quadrangula fed on cattle manure at low diet density (5mg). In this research, maximum (800±34.6µm) (Mean ±SE) and minimum (521±31.6µm) body length of C. quadrangula measured when fed with cattle manure at low diet density and S. quadricauda at high diet density, respectively. In conclusion, the results of current study illustrated that S. quadricauda as diet gave better performance for rearing of C. quadrangula compared to other diet treatments.

This study evaluated the suitability of canola oil as a source of supplemental dietary lipid for rainbow trout. Triplicate groups of the 30 fingerlings held under identical culture conditions were fed twice daily by iso-nitrogenous, iso-calorific and iso-lipidic diets for eight weeks. Experimental diets consisted of 30.3% protein, 18.7 kJg^-1 energy and 16.7% lipid from fish oil (FO), canola oil (CO) and 1:1 blend of the two oils (FCO). Moisture, ash, protein, lipid, final body weight, condition factor, feed conversion ratio, survival and hepatosomatic indices were not affected by treatments. Specific growth rate and weight gain of fish reared on fish oil diet (FOD) and canola oil diet (COD) were significantly higher than those fed with the fish and canola oils diet (FCOD). Protein efficiency ratio was highest in fish fed with the COD. Whole body fatty acid compositions mirrored those of diet treatments. The highest amounts of HUFAs were detected in fish fed with FOD, which was significantly different from other treatments. In all treatments PUFAs/SFAs and n-6/n-3 ratios were higher than 0.45 and lower than 4, respectively. Our results indicate the fingerlings can be reared on diets in which FO has been replaced with CO, with no significant effects on fish growth performance.

Background: The International Agency for Research on Cancer (IARC) recently classified opium use as a Group 1 carcinogen. However, much remains to be studied on the relation between opium and cancer. We designed the Iranian Opium and Cancer (IROPICAN) study to further investigate the association of opium use and cancers of the head and neck, bladder, lung, and colon and rectum. In this paper, we describe the rationale, design, and some initial results of the IROPICAN Study. Methods: The IROPICAN is a multi-center case-control study conducted in 10 provinces of Iran. The cases were all histologically confirmed and the controls were selected from hospital visitors who were free of cancer, were not family members or friends of the cancer patients, and were visiting the hospital for reasons other than their own ailment. The questionnaires included detailed questions on opium use (including age at initiation, duration, frequency, typical amount, and route), and potential confounders, such as tobacco use (e.g., cigarettes, nass and water-pipe), and dietary factors. Biological samples, including blood and saliva, were also collected. Results: The validation and pilot phases showed reasonably good validity, with sensitivities of 70% and 69% for the cases and controls, respectively, in reporting opium use. The results also showed excellent reliability, with intra-class correlation coefficients of 0.96 for ever opium use and 0.88 (95% CI: 0.80, 0.92) for regular opium use. In the main phase, we recruited 3299 cancer cases (99% response rate) and 3477 hospital visitor controls (89% response rate). The proportion of ever-use of opium was 40% among cases and 18% among controls. Conclusion: The IROPICAN study will serve as a major resource in studies addressing the effect of opium on risk of cancers of the head and neck, bladder, lung, and colon and rectum. publishedVersion