Simultaneous Determination of Nitrite and Nitrate in Milk Samples by Ion Chromatography Method and Estimation of Dietary Intake

The presence of nitrate and nitrite in foods may be considered hazardous after ingestion in the gastrointestinal tract due to their reaction with naturally occurred secondary amines to form potentially carcinogenic nitrosamines. Due to this fact, a new method was developed in this study for the simultaneous determination of nitrite and nitrate in milk samples using by ion chromatography. Proposed mobile phase composed of sodium hydrogen carbonate and sodium carbonate (1.0 and 3.2 mmol/L) with a flow rate of 0.7 ml/min. The average recoveries for nitrate and nitrite were higher than 86 and 88, respectively. The limit of detection for nitrate and nitrite were 0.24 and 0.09 mg/L, respectively. The results of 102 real milk samples showed nitrate was found in all of the samples (100) with a mean of 34 ± 11 mg/L, while nitrite was found in none of the samples. The mean intake of nitrate in all age groups was lower than World Health Organization guideline. The present assessment concludes that the maximum contaminant level was equal to 82.8 mg/L nitrate. This method was fast, sensitive and accurate and is capable of being an alternative method in food control laboratories for investigation of nitrite and nitrate content. This is the first study of the determination and survey of nitrite and nitrate and exposure assessment of the Iranian population to nitrite and nitrate level in milk, which was widely used in infants and adolescents as one of the basic food components. Copyright © Taylor & Francis Group, LLC

Associations between Western and Mediterranean-type dietary patterns and anxiety and stress

In this study we investigated the relationship between dietary patterns and anxiety and stress in adults living in Shiraz, Iran. In a cross-sectional design, 416 subjects (180 men and 236 women) aged 20 to 50 years were selected by stratified multistage random sampling. Dietary intakes were assessed using a semi-quantitative food frequency questionnaire (FFQ). Mental health information was collected by depression, anxiety and stress scale (DASS) questionnaire. Three major dietary patterns were extracted by factor analysis: vegetable, Western, and Mediterraneantype dietary patterns. Regression analysis showed a strong positive association between Western dietary pattern and anxiety (β=0.66; 95% CI: 0.03, 1.28), and stress (β=0.84; 95% CI: 0.1, 1.57). Also, there was an inverse association between Mediterranean-type dietary pattern and anxiety (β= ‒0.81; 95% CI: ‒1.43, ‒0.19). These associations remained statistically significant even after adjustments for demographic characteristics, physical activity, smoking, body mass index, and energy intake. No association was found between vegetable dietary pattern and any of the assessed psychiatric disorders

Effect of the timing of initial feeding on growth and survival of Persian sturgeon (Acipenser persicus) larvae

Effect of the timing of first feeding (9, 10, 11, 12 and 13 days post hatch) with a live food (Artemia naupli) on Persian sturgeon was examined at 17.7±0.8 and 18.1±0.4°C. The results showed that the timing of first feeding affected on weight, length, length-weight ratio and specific growth rate, but one day delay in the timing of initial feeding doesn't affect on the survival and two days delay in the timing of initial feeding doesn't affect on the condition factor. Results of this research showed that some factors such as weight, length, length-weight ratio and specific growth rate, are more suitable than survival and condition factor for exhibiting of effects of delay in the starting time of initial feeding in Persian sturgeon fish larvae. Thus it is better that the initial feeding of Persian sturgeon at 17.7±0.8 and 18.1 ±0.4°C started on 12 and 9 days after hatching, respectively, as well as more delay in initiating exogenous feeding has negative effects on growth of larvae

Adaptive mesh optimization for simulation of immiscible viscous fingering

Viscous fingering can be a major concern when waterflooding heavy-oil reservoirs. Most commercial reservoir simulators use low-order finite-volume/-difference methods on structured grids to resolve this phenomenon. However, this approach suffers from a significant numerical-dispersion error because of insufficient mesh resolution, which smears out some important features of the flow. We simulate immiscible incompressible two-phase displacements and propose the use of unstructured control-volume finite-element (CVFE) methods for capturing viscous fingering in porous media. Our approach uses anisotropic mesh adaptation where the mesh resolution is optimized on the basis of the evolving features of flow. The adaptive algorithm uses a metric tensor field dependent on solution-interpolation-error estimates to locally control the size and shape of elements in the metric. The mesh optimization generates an unstructured finer mesh in areas of the domain where flow properties change more quickly and a coarser mesh in other regions where properties do not vary so rapidly. We analyze the computational cost of mesh adaptivity on unstructured mesh and compare its results with those obtained by a commercial reservoir simulator on the basis of the finite-volume methods

The determination of LC50 of diazinon and it's sub-lettal effect on haematological indices of beluga (Huso huso)

The acute toxicity and effects of diazinon on some hematological indices of Beluga (Huso huso) juveniles weighting 4.1±0.12 grams was assessed following the 0.E.C.D. direction in a static temperature in the range 20.27±2.05°C. The 96h LC50 value of diazinon for beluga juveniles was 5.821. Also, the maximum allowable concentration of diazinon in natural waters for beluga was determined to be 0.5821mg/L. Based on the toxicity table of insecticides, diazinon was listed as toxic for beluga .The clinical symptoms that were observed in this study consisted of lordosis and neural paralytic syndrome in fish exposed to the pesticide. Some abnormal reactions such as losing the balance when swimming and swimming in a half circle; expressive pigmentation mainly on the dorsal part were seen in the juveniles. Examination of hematological indices was performed on control and experimental specimens of beluga weighting 16.08 grams on average that were treated with 96h exposure to diazinon in a concentration lower than LC50 96h. The experimental group of beluga showed significantly lower value (P<0.05) of ,erythrocyte (RBC) and leukocyte count, hemoglobin content (Hb), and haematocrite (PCV), MCV, MCH and relative lymphocyte and eosinophil counts compared to the control group In comparison, the relative heterophil count in the juveniles of the experimental group was significantly higher than the control group. By observing a decrease in the amount of leukocyte profile specially lymphocytes which are important in non-specific immunity of the fish, it can be said that diazinon may cause a decrease in the non-specific immunity of beluga

Numerical Investigation of the Plasma-Assisted MILD Combustion of a CH4/H2 Fuel Blend under Various Working Conditions

The effects of plasma injection upon MILD combustion of a mixture of methane and hydrogen are investigated numerically. The injected plasma includes the flow of a highly air-diluted methane including C2H2, C2H4, C2H6, CH, CH2, CH3, CO, and CO2. The results show that among all the constitutes of plasma, CH3 is the most effective in improving the characteristics of MILD combustion. Injection of this radical leads to the occurrence of reactions at a closer distance to the burner inlet and thus provides longer time for completion of combustion. Further, mass fractions of OH, CH2O, and HCO are considerably affected by the injections of CH3, indicating structural modifications of the reacting flow. Importantly, as Reynolds number of the plasma flow increases, the volume and width of the flame decrease, while the formations of prompt and thermal NOx are intensified. However, injection of CH3, as plasma, reduces the emission of thermal NOx

Экологические преимущества солнечной энергии для предотвращения потерь энергии и укрепления окружающей среды Йемена

In this study, we shed light on the extent of the difficulties faced by Yemenis as a result of the lack of government power and the search for alternatives due to the high cost of fuel, and how they eventually transitioned to solar.Определены масштабы трудностей, с которыми сталкиваются йеменцы в результате отсутствия государственной власти и поиска альтернатив из-за высокой стоимости топлива, и рассмотрено то, как они в конечном итоге перешли к солнечной энергии

Effect of different levels of Azolla meal on growth performance and digestibility of common carp (Cyprinus carpio)

In this study, the effects of different dietary levels of Azolla meal were investigated on growth performance and digestibility of common carp (Cyprinus carpio) fingerlings during 60 days. Five experimental diets approximately iso-protein (30%) and isolipidic (10%), were formulated with different levels of Azolla meal consisting of 0, 15, 25, 35 and 45%, respectively. In each experimental treatment, triplicate groups of common Carp fingerlings (16.5± 0.2 g) were used in a completely randomized design. Twenty fish were assigned to each experimental unit and stocked in 300 L tank. The results showed that the use of Azolla meal up to 15% had no negative effect on growth performance. The growth of fish was reduced significantly with increasing Azolla meal level of more than 15% of diet. Based on results, the apparent digestibility coefficients (ADC) of dry matter decreased with increasing Azolla meal in diets. The highest ADC of protein was observed in control treatment. However, no significant difference was observed between the treatment 2 (diet with 15% Azolla meal) and control (without Azolla meal) for ADC of protein. In general, results of the present study showed that Azolla meal can be used up to 15% in Cyprinus carpio diet