Studiul histerezisului capilar în soluri cu textura medie folosind modelul Preisach

The purpose of this paperis to studythe physical properties of the soil using a phenomenological model which should be able to describe the capillary hysteresis of water from pores of the medium-textured soil.The proposed model is Preisach typeand has been used successfully to describe the hysteresis of nonlinear phenomena in physics, biology or economics. This model has the advantage ofbeingeasily adapted. We had expanded this model to study the pressure exerted by water in the processes of drying and wetting of the soil. The developed and implemented model, unlike other models, takesintoconsideration the way in which interconnected pores are filled and emptied.Our study presents a new method of assessing the water circulation in soil pores with medium texture from greenhouses. The results are useful to make the irrigation systems used in gardening more efficient, from economicalpoint of view

Analiza conţinutului de proteine din plasma sanguină a animalelor erbivore şi carnivore

This paper focuses on determining the concentration of blood plasma proteins for different domestic animals to highlight the link between diet and proteins content. Blood plasma from two categories of animals, herbivores and carnivores (horse, cow, goat, sheep and dog) was used for this study, the protein content being compared to that found in human and turkey blood (omnivorous). Our results showed that the samples of blood taken from dogs have the lowest proteins content, although they consume food rich in proteins. The highest value of proteinemia is found in horse blood, even if it is an herbivorous animal that consumes food rich in fibbers and vitamins. The hypothesis that herbivores have a higher content of proteins in blood than carnivores is supported by the results obtained for samples of cow, goat and sheep blood

Studiu spectrofotometric al efectelor metalelor grele în sângele animal

n order to obtain information on the alteration of blood structure in the presence of heavy metals, mercury and lead, the modification of the absorption maxima of oxyhemoglobin was analyzed. Blood samples were collected from three healthy animal species: cows, horses and dogs.For the samples, 20 ml of 5% HgCl2and Pb(NO3)2solution and 0.5 ml of blood from each species have been prepared.The obtained experimental results have shown that heavy metals affect certain biophysical characteristics of hemoglobin in the blood of the studied animals. The strongest effect has been obtained in the case of mercury, which is the most toxic heavy metal; for the horse blood sample at the wavelength of 410 nm, the absorption measurement gave an error, indicating that the sample was severely degraded

Creşterea riscului de apariţie a tornadelor în România datorită schimbărilor climatice

The aim of this paper is to analyze the causes that lead to the emergence of tornadoes in very low risk areas (Romanian territory) in the conditions of the climatic changes of the last 100 years.Thisextremely violent meteorological phenomenonisgeneratedby very specific metrology conditions which make the likelihood of their occurrence to be low. The relationship between the occurrence of tornadoes in tornado-free areas and global warming is still unclear. In the present paper we have made a comparative study to estabilished if the whether condition which generated the Facaeni tornado, in2002, was random occurrence or was generated by the warming of the atmospherein terms of climate change. The study is based on the analysis of the factors that generated the tornado, the geographic position, the climate of the region and the warming athmosphere over the last 55 years.Our analysis established that Facaeni tornado was EF3 intensity and representsa turningpoint in the study of tornadoes in Romania

Evaluation of the nutrients uptake by tomato plants in different phenological stages using an electrical conductivity technique

Nutrient consumption by plants depends on the growth stage and environmental conditions. In general, plants take up species of elements at different speeds. We monitored and recorded the electrical charge flow through xylem sap of tomato plants (Brillante F1) using femto/picoammeter equipment (Keysight B2981A). This technique evaluates the nutrient uptake of tomato treated with the most common macronutrients (KNO3; KH2PO4; Ca(NO3)2; KCl) by monitoring the electrical conductivity for 24 h. The electrical conductivity of each treatment correlated with the plant growth and development stages. The results showed that the tomato plants had a high consumption of nutrients in the vegetative stage, while in other stages, they had a specific consumption, like phosphorus for bulb formation, potassium for increasing the number of flowers and water for the ripening of fruits. The quantitative evaluation of the ions absorbed by the plant was based on the magnitude and shape of the electrical conductivity curves. Our technique is an efficient method to determine nutrient consumption and is useful in predicting the deficiency of a certain element in tomato plants

Rezultate privind producţia şi parametri fiziologici ai cultivarului de tomate Siriana F1 sub influenţa stimulatorilor convenţionali şi neconvenţionali

Tomato (Lycopersicon esculentum Mill.) is a leading vegetable crop, in terms of global cultivation (open field and protected area) and consumption. The chemical nutrients of plants serve as critical factors that determine the plant growth and vigour, also the crop yield. In addition, these nutrients play aparticular role in contributing to the survival of crop plants under environmental stress conditions. Under climatic or nutritional stress, the productivity is affected in a percentage that range between 45-70%. In this study, the influence of unconventional and conventional stimulants was evaluated for Siriana F1 in term of physiological parameters and yield. In order to achieve this, at UASVM Iasi was carried out an experiment on a tomato crop from the Siriana F1 hybrid, where six treatments were tested compared to a control version.The highest values of the analyzed physiological parameters were recorded under treatment of Au -citrate C; for the total pigments this variant had the lowest value, respectively 14.9 CCI

Epidemiology and clinical presentation of dogs infected with sarcoptic mange

Sarcoptic mange in dog is a common parasitic dermatitis, especially in non-controlled, stray dogs that develop evocative clinical signs. The present study includes 48 dogs, with different backgrounds, both privately owned and dogs from shelters. We searched for predisposing factors for contacting sarcoptic mange, such as: age, sex, breed, source of contamination. Their age ranged from 1.15 months to 12 years (with more than a half being under 1 year old), they were mostly common or cross-breed dogs, and the sex ratio was almost equal, with 25 females and 23 males. All dogs were naturally infected with Sarcoptes scabiei, as confirmed by identification on the microscope of skin scrapings from different body areas. Furthermore, we aimed to have a general idea concerning the severity of infection with Sarcoptes scabiei in the dogs we studied. The dogs received a clinical score based on the evaluation of typical signs that appear in sarcoptic mange such as alopecia, erythema, scales/crusts and the extent of mange on the cutaneous surface on different body parts (head, trunk, legs, tail). The most affected body part was the head, followed by the trunk and the most scored sign was the extent of affected skin and alopecia. The treatment consisted in the administration of either afoxolaner (Nexgard®), twice at a monthly interval (2.7-6.9 mg/kg), either sarolaner (Simparica®), twice at a monthly interval (2-4 mg/kg), or doramectin (Dectomax®) 0.2 mg/kg, twice at 14 days interval

Chaos Synchronization of Two Györgyi–Field Systems for the Belousov–Zhabotinsky Chemical Reaction

Chemical reactions with oscillating behavior can present a chaos state in specific conditions. In this study, we analyzed the dynamic of the chaotic Belousov–Zhabotinsky (BZ) reaction using the Györgyi–Field model in order to identify the conditions of the chaos behavior. We studied the behavior of the reaction under different parameters that included both a low and high flux of chemical species. We performed our analysis of the flow regime in the conditions of an open reaction system, as this provides information about the behavior of the reaction over time. The proposed method for determining the favorable conditions for obtaining the state of chaos is based on the time evolution of the intermediate species and phase portraits. The synchronization of two Györgyi–Field systems based on the adaptive feedback method of control is presented in this work. The transient time until synchronization depends on the initial conditions of the two systems and on the strength of the controllers. Among the areas of interest for possible applications of the control method described in this paper, we can include identification of the reaction parameters and the extension to the other chaotic systems

Valorificarea potentialului economic al masivului Rarău pe baza condiţiilor climatice

The Rarau Massif is a mountain area exploited for tourism purposes since 1928, but recent climate change requires a reanalysis of the new weather conditions to propose a new economical capitalizing plan.In this paper we analyzed the main meteorological elements (temperature, precipitation, speed and frequency of wind) recorded by the Rarau meteorological station to highlight the economic potential of the area.In the Rarau massif, the air temperature during the summer months has increased, which is favourable for mountain tourism. This hypothesis is also supported by the decrease of the amount of rainfall during the summer. Our analysis shows that the heating of the air is due to the warm wind, predominantly in the east -west direction with relatively slow speeds (2 m/s). Instead, the temperatures have decreased in January -February which supports the construction of one of the longest winter sports slope in Romania

Chaos Synchronization of Two Györgyi–Field Systems for the Belousov–Zhabotinsky Chemical Reaction

Chemical reactions with oscillating behavior can present a chaos state in specific conditions. In this study, we analyzed the dynamic of the chaotic Belousov–Zhabotinsky (BZ) reaction using the Györgyi–Field model in order to identify the conditions of the chaos behavior. We studied the behavior of the reaction under different parameters that included both a low and high flux of chemical species. We performed our analysis of the flow regime in the conditions of an open reaction system, as this provides information about the behavior of the reaction over time. The proposed method for determining the favorable conditions for obtaining the state of chaos is based on the time evolution of the intermediate species and phase portraits. The synchronization of two Györgyi–Field systems based on the adaptive feedback method of control is presented in this work. The transient time until synchronization depends on the initial conditions of the two systems and on the strength of the controllers. Among the areas of interest for possible applications of the control method described in this paper, we can include identification of the reaction parameters and the extension to the other chaotic systems