Osmotically volumetric urine index in early recognition and evaluation of the central diabetes insipidus correction efficiency

Purpose of the work: to develop an information criterion for early recognition and evaluation of the homeostasis correction efficiency in central diabetes insipidus. Materials and methods. 48 neurosurgical patients who underwent traumatic brain injury (21), surgery for a brain tumor (14) and stroke (13), whose course of the disease was complicated by central diabetes insipidus, have been examined. The diuresis rate and urine density (refractometrically) were studied in each of its portions excreted out of the body within an hour. According to the indicator of osmotic density and the range of urine output, an information criterion for the diagnosis of diabetes insipidus and the dynamics of its course was developed – the osmotically volumetric urine index (OVUI). Results and discussion. With physiological water input, 0.8-1.0 ml∙kg-1of urine is usually excreted from the human body within an hour. Concurrently, its specific gravity (urine density, UD) is 1012-1025. In 12 patients of the comparison group without diabetes insipidus, the OVUI index was 8.0-12.0. Central diabetes insipidus is characterized by significant homeostasis disorders: blood hypohydration and hyperosmolarity due to violation of hypothalamic-pituitary regulation of antidiuretic hormone secretion. In these conditions the osmotically volumetric urine index decreases to indicators ˂ 1.0. The criterion for the intensive therapy efficiency for homeostasis disorders in diabetes insipidus is OVUI increase above 1.0. The article presents a clinical case of timely recognition and successful correction of homeostasis in a patient with traumatic brain injury complicated by central diabetes insipidus.  Conclusions. The osmotically volumetric urine index – is an indicator that allows diagnosing diabetes insipidus in its early manifestations and timely preventing a violation of homeostasis. With the norm of OVUI at 8.0-12.0, its decrease to ˂ 1.0 indicates the presence of diabetes insipidus in the patient. Timely and adequate correction of disorders of hydration, blood osmolarity and the use of desmopressin lead to the OVUI normalization, which is a dynamic marker of the efficiency of intensive therapy of diabetes insipidus. The simplicity of the study (the possibility of carrying it out directly at the patient’s bedside), as well as the informativeness of the OVUI diagnostic and prognostic values deserve to be used in clinical practice

Stress state of loaded with intrinsic pressure cylindrical shell of piecewise-permanent thickness

Запропоновано методику визначення напруженого стану навантаженої внутрішнім тиском циліндричної оболонки кусково-сталої товщини, залежної від осьової координати. Методика базується на використанні сплайн-перетворення аргументу. Вихідне рівняння зводиться до диференціального рівняння зі сталими коефіцієнтами та сингулярною правою частиною. Для побудови його розв’язку використовується інтегральне перетворення Фур’є. Досліджується залежність напружень від геометричних характеристик оболонки.The method of determination of the stress state of loaded with intrinsic pressure cylindrical shell of piecewise-permanent thickness, dependency upon an axial coordinate, have been designed. The method is based on the use of argument spline-transformation. The initial equation is reduced to a differential equation with constant coefficients and singular right part. For the construction of its solution the integral Fourier transformation is used. Dependence of stresses on geometrical descriptions of shell is investigated

The stress state of the ground array during realization of horizontal making by method of compression

Запропоновано математичну модель руху ґрунтових частинок при проведенні горизонтальної виробки шляхом ущільнення ґрунтового масиву. Приймається, що ґрунт – невагоме ізотропне середовище, яке володіє тертям і зчепленням та задовольняє умови плоского напруженого стану. Припускається, що деформації та напруження розподілені по контуру виробки рівномірно. Досліджено напружено-деформований стан ґрунтового масиву в околі виробки.The mathematical model of motion of the ground particles during realization of the horizontal making by the compression of the ground array is offered. It is accepted that soil is a weightless izotropic environment which owns a friction and coupling and satisfies the terms of the flat stress state. It is assumed that deformations and stresses are up-diffused for contour of making evenly. The strain-stress state of the ground array in the zone making is investigated

Temperature field and stressed state of composite bridge span investigation

Наведено результати експериментальних вимірювань температури сталезалізобетонної балки прогонової будови моста. Запропоновано математичні моделі теплопровідності та напружено-деформованого стану фрагмента балки, лицеві поверхні якого вільні від навантажень і нагріті до різних температур, а бокові поверхні жорстко закріплені. Для дослідження напружено-деформованого стану фрагмента використовуються рівняння термопружності. Припускається, що температура залежить лише від координати, напрямленої вздовж осі аплікат. Приймається, що на межі між різнорідними складовими фрагмента балки виконуються умови ідеального теплового та механічного контакту.Railway and road bridges are the significant part of the national achievement, one of the most important components of Ukraine’s infrastructure. At the same time their maintenance becomes worse results in the traffic black out because of the poor technical condition or accidents of the bridge, and it causes significant social and economic losses. Neither society, nor the authorities of Ukraine treat this situation as the social and economic risk to the country. However, the problems of the area are urgent. The technical condition of railway and road bridges in Ukraine is as follows: 10% of railway bridges and 54% of bridges in public roads use do not meet the requirements of DBN V.2.3. 14:2006 “Bridges and pipes. The design rules”, 11% of bridges on public roads require immediate overhaul or reconstruction. Adoption of the science-based decisions concerning the need for renewal of one or another bridge element is possible on the basis of the objective estimation of its technical condition and residual resource. One of the most effective ways to evaluate the technical condition of structures and buildings, operating with external force loads and variable seasonal and diurnal temperatures are monitoring of their stress-strain state, which makes it possible to obtain objective information on the history of the load element design for its life cycle, development of its damages and to identify its serviceability term. The results of this monitoring will make possible to detect abrupt and gradual reduction of carrying capacity of individual structural elements;to calculate using appropriate mathematical models residual resource of the individual structural elements and structures in general. A complex design or construction monitoring, consisting of various structural elements, can be realized by the continuous measurement of the local deformations of the most critical elements with the subsequent calculation of the stress-strain state of the whole structure using appropriate mathematical models. Thus, for the monitoring system of such structures it is necessary to develop the methods of determining the stress-strain state individual structural elements composite beams spans bridge structures in particular, which are under the influence of climatic variable temperatures. These studies along with the studying of the effects of constant and variable loads, are the basis for estimation of the strength and reliability of the spans bridge structures. The results of experimental measurements of composite beam bridge spans temperature are presented in the paper. The mathematical models of the heat conductivity and the stress-strain state of the fragment beams, the facial surfaces of which are free from stress and heated to different temperatures, and the lateral surfaces are rigidly fixed, are proposed. To study the stress-strain state of the fragments the equations of thermo-elasticity are used. The temperature is expected to depend only on the coordinate directed along the applicate axis. At the border between heterogeneous components inside the beam the ideal thermal and mechanical contact conditions are assumed to be provided

Optimization of nitrogen fertilizer of the dark-gray soldized soil of the western forest steppe for using nitrification inhibitor

Nitrogen is a key element for the growth and yield of all crops. Increased doses of nitrogen do not give the expected return, create a danger of leaching of nitrates, activate the emission of nitrous oxide. These problems make it necessary to solve the urgent issue of optimizing nitrogen nutrition using the nitrogen stabilizer nitrapyrin. The purpose of our research under conditions of sufficient moisture in the Western Forest Steppe was to find out the effect of the urease inhibitor on the agrochemical parameters of the dark gray forest podzolized light loam soil, as well as the effect on the yield of winter barley. We conducted field experiments at the Lviv National University of Nature Management. We used traditional methods of field research and standardized methods of laboratory analysis. A positive effect of the use of the nitrogen stabilizer nitrapyrin on the funds of nitrogen, phosphorus and potassium available for nutrition, as well as on the reduction of soil acidity, was established. The highest content of easily hydrolyzable nitrogen was achieved when applying N23P60K60 in autumn + N97 in the phase of vegetation recovery with nitrapyrin – 132 mg/kg of soil. This was 28 mg/kg more than the traditional fertilization system without nitrapyrin (N60P60K60). Application of 120 kg/ha of nitrogen in the form of urea created a reserve 3.3 times higher, and ammonium nitrate created a reserve 3.6 times higher than the unfertilized version. Nitrapyrin, a stabilizer of nitrates, made it possible to limit their formation with the introduction of urea by 3 5%, ammonium nitrate by 10 %. The nitrogen application rate of N120 kg/ha per year led to the annual emission of nitrous oxide in the amount of 121.5 kg/ha. Nitrapyrin limited the amount of nitrous oxide emission by 3.3–7.2 kg/ha, depending on the amount of nitrogen application rate. The use of ammonium nitrate at the rate of N120 when applied in the spring caused the highest level of nitrogen oxide emissions (29.5 kg/ha of soil). However, the application of this fertilizer and inhibitor reduced gaseous nitrogen losses to 25.9 kg/ha when applied to restore vegetation. The introduction of N97 (ammonium nitrate) + N-Lok Max under winter barley during the restoration of vegetation on the background of N23P60K60 under plowing gave the highest average yield in the experiment for 2020–2022 – 7.65 t/ha, for 2022 – 7.90 t/ha. The 3D regression model of winter barley grain yield under the influence of the synergistic effect of both forms of nitrogen illustrates the importance of balancing the funds of forms of this nutrient element in the soil