SOUTHERN JOURNAL OF SCIENCES

Background: In line with the current global energy crisis, there is an urgent need to seek cheap energy sources. This study has utilized waste materials for synthesizing biodiesel, an environmentally friendly alternative energy. Aim: This study aimed to prepare low-cost carbon-based zirconium impregnated heterogeneous catalysts using wood dust to produce biodiesel from waste vegetable oil (WVO). Methods: Response Surface Methodology via Central Composite Design (RSM-CCD) optimized the biodiesel production process. The physico-chemical properties of waste vegetable methyl ester were determined following the American Standard Testing of Materials (ASTM). In addition, the catalyst morphology and elemental composition were determined using Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray (EDX), respectively. Results and Discussion: The optimum conditions were observed to be 8:1 methanol/oil ratio, 5 wt% catalyst loading, 55 °C temperature, and 3 hours of reaction time. The corresponding response was observed to be 98.39%. Conclusions: The experimental analysis confirmed that the synthesized catalyst from wood dust under optimized conditions transesterified the waste vegetable oil into biodiesel with properties that comply with American Standard Testing of Materials.

The pre-sowing treatment of scarlet sage (Salvia splendens Ker Gawl.) seeds with 4-methyl-2-piperidin1-yl-pyrimidine-5-carboxylic acid at concentrations of 0.01, 0.05, and 0.1% proved to have an obvious inhibiting effect. Prior to sowing, the seeds of Salvia splendens were soaked in a water suspension of 4-methyl-2-piperidin-1-yl-pyrimidine-5-carboxylic acid and 4-methyl-2-morpholin-4-pyrimidine-5-carboxylic acid with concentrations of 0.01%, 0.05%, and 0.1% for 18 hours. On the 42nd day of the experiment, the seedlings, having been preliminarily hardened for 12 days, were removed from the greenhouse and planted on the field. The pre-sowing treatment of Salvia splendens seeds with 4-methyl-2-morpholin-4-pyrimidine-5-carboxylic acid proved to have the inhibiting effect at concentrations of 0.01 and 0.05%. The height of the seedlings decreased by 13.3-43.7%. It was revealed that 4-methyl-2-piperidin-1-yl-pyrimidine-5-carboxylic acid at concentrations of 0.01, 0.05, and 0.1% decreased the growth of the seedlings by 30.4-43.7%, and 4-methyl-2-morpholin-4-pyrimidine-5-carboxylic acid at concentrations of 0.01 and 0.05% decreased the growth of the seedlings by13.3-22.2%. By contrast, the effect of pyrimidinecarboxylic acids on seed germination and plant height of another annual flower – spreading marigold (Tagetes patula L.) was stimulating. It was investigated some different concentrations from 0.01 to 0.05 %. The same concentrations of identical compounds were tested, but effects from them were opposite for Tagetes patula, and Salvia splendens seedlings. Сonsequently, the species-specific effect of pyrimidinecarboxylic acids on seed germination and plant height for ornamental grasses takes place. Therefore,4-methyl-2-piperidin-1-yl-pyrimidine-5-carboxylic acid and 4-methyl-2-morpholin4-pyrimidine-5-carboxylic acid are recommended as growth retardants for Salvia splendens. 

Background: Despite innovations in orthopedic dentistry, the manufacture of removable dentures belongs to the most popular orthopedic care category. Removable dentures are combined stimuli that affect the mucous membrane and neuro-receptor apparatus. Acrylic plastic prostheses, widely used in prosthetic dentistry, have a negative side mechanical, chemical-toxic, sensitizing, and thermal insulating effect on oral tissue and prosthetic impression area. This is often complicated by a violation of the biocenosis of the oral cavity, the growth of pathogenic microflora that releases toxins, especially an increase in the number of yeast colonies that irritate the oral mucosa and prosthetic stomatitis. According to the WHO, one-fifth of the world s population suffers or has suffered various candidiasis forms at least once. The worldwide increase in the incidence of the disease is primarily related to the fact that this infection is opportunistic, more than half of the world s population is a carrier of fungi of this kind, i.e., in most cases, it is an endogenous infection, which makes candidiasis different from other opportunistic mycoses. Aims: The purpose of this study was to study the prevalence of candidiasis in patients using removable dentures and to evaluate the effectiveness and prevention of candidiasis treatment. Methods: 100 patients with oral candidiasis of various age groups from 45 to 65 years were observed. Of these, 60 patients with removable plate prostheses; 40 patients with partially removable prostheses. Results and Discussion: Chronic forms of candidiasis were diagnosed in 40 patients and with exacerbation of chronic forms of candidiasis-60 people. The number of untreated carious cavities and poor hygienic condition of the oral cavity directly affects the severity of candidiasis. Acute forms of candidiasis were observed mainly in patients with high DMF and PMA indices. The severity of candidiasis depends on the degree and duration of wearing dentures and hygienic conditions - the most severe forms of invasive candidiasis were observed in the presence of removable plate prostheses, the complete absence of teeth, and the use of a prosthesis for more than 10-15 years. A combined lesion of the oral mucosa and the red border of the lips was observed mainly in patients older than 60 years. Conclusions: The presence of candidiasis in the oral cavity in patients with removable plate prostheses leads to a statistically significant change in the indicators of local immunity of the oral cavity: an increase in the concentration of serum IgG and IgA and the values of the coefficient of the balance of local immunity factors.