Monitoring of the main indicators of milk quality of Ukrainian dairy produc-ers

The composition and properties of milk are significantly influenced by various factors, such as the breed of cows, stages of lactation, the environment, as well as its temperature treatment. In the research carried out in 2017–2022, ultrasonic analysis of 56 samples of different types of dairy products was carried out: pasteurized and ultra-pasteurized milk of the largest Ukrainian producers of dairy products and milk produced at small enterprises, as well as a dairy product made in laboratory conditions from milk powder (reconstituted milk). The following indicators of milk composition were determined by the method of ultrasonic analysis, such as the content of fat, protein, lactose, solids non fat (SNF), and freezing temperature. The fat content in the samples was in the range of 2.5–3.2 %, the protein content was on average 3.3%, and a clear pattern of increasing the protein content with increasing fat content was observed. The content of SNF was on average 8.4 %, and lactose in the range of 4.5–5.5 g/100 g of milk; in the produced reconstituted milk, the lactose content was somewhat lower and averaged 3.5 %. The freezing temperature of the studied samples ranged from -0.50 ºC (reconstituted milk) to -0.60 ºC (pasteurized and ultra-pasteurized). The method of principal components analysis was used to process the obtained data array. Application of the method of principal components analysis (PCA) made it possible to divide all the studied samples into two groups. The first compact group consists mainly of samples of pasteurized and ultra-pasteurized milk from well-known producers of dairy products. The second diffuse group consists of samples of reconstituted milk, and this group includes several samples of pasteurized milk of a low price category from small producers. The analysis of the eigenvectors and eigenvalues of the PCA indicates that the main factors affecting the grouping of the samples are the content of lactose, protein and the value of the freezing temperature. At the same time, the application of PCA modeling did not reveal any grouping of samples by seasons and years. In the future, based on this method, a discriminatory model can be made, which will allow to quickly detect falsified samples or samples manufactured in violation of technical conditions

Microprocessor's system of orientation solar panel towards to the sun

В роботі розглянуто будову мікропроцесорної слідкувальної двокоординатної системи панелі сонячних батарей в напрямку сонця підвищеної точності управління.There was reviewed design of the microprocessor trailing two-coordinating system of solar panel towards to the sun with the high accuracy control in this article

Визначення триптофану в молоці

Tryptophan or L-tryptophan is one of the essential amino acids for the human body. An important component of the human diet, L-tryptophan is not only involved in protein synthesis in the body, but is also crucial for a number of metabolic functions. One of the important sources of tryptophan for the human body are dairy products, and their feature is the fact that milk itself contains the best ratio of tryptophan/competing amino acids, which is necessary for the synthesis of serotonin. Since tryptophan is thermolabile, one of the factors that can affect its content is heat treatment of milk. The standard and certified method for determining tryptophan in milk is high-performance liquid chromatography with fluorescence detection. Tryptophan belongs to fluorophores and fluoresces most strongly among all amino acids. It absorbs electromagnetic radiation with a wavelength of 290 nm and emits in the range of 300–350 nm. In the presented study, tryptophan was determined by the method of fluorescence spectroscopy without chromatographic separation of 18 samples of drinking milk from well-known Ukrainian producers of dairy products, which differed in the method of heat treatment and manufacturing technology. Fluorescence spectra were recorded on a Perkin-Elmer LS-55 fluorescence spectrometer; the content of dry skimmed milk residue and lactose in milk samples was determined on an ultrasonic milk analyzer “Ekomilk-Bond” (Bulgaria). Sample preparation of milk samples for the determination of tryptophan was carried out according to DSTU ISO 13904:2008. Research has shown that the content of tryptophan in milk samples from Ukrainian dairy producers ranges from 189.5 to 515.1 mg/l, which is basically consistent with literature data. Dependence of the method of heat treatment of milk on tryptophan content was not found. Obviously, first of all, the tryptophan content in milk will be influenced by the total protein content in the product.Триптофан, або L-триптофан – одна з незамінних амінокислот для людського організму. Важливий компонент раціону людини, L-триптофан не тільки бере участь у синтезі білка в організмі, а й також має вирішальне значення для низки метаболічних функцій. Одним із важливих джерел триптофану для людського організму є молочні продукти, а їхньою особливістю є те, що саме молоко містить найкраще співвідношення триптофан / конкуруючі амінокислоти, яке необхідне для синтезу серотоніну. Оскільки триптофан є термолабільним, одним із факторів, що може впливти на його вміст, є термообробка молока. Стандартним і сертифікованим методом визначення триптофану у молоці є високоефективна рідинна хроматографія з флуоресцентним детектуванням. Триптофан належить до флуорофорів і найсильніше флуоресціює серед всіх амінокислот. Він поглинає електромагнітне випромінювання з довжиною хвилі 290 нм і випромінює в діапазоні 300–350 нм. У дослідженні проведено визначення триптофану методом флуоресцентної спектроскопії без хроматографічного розділення 18 зразків питного молока відомих українських виробників молочної продукції, які відрізнялися способом термообробки та технологією виготовлення. Спектри флуоресценції записувались на флуоресцентному спектрометрі Perkin-Elmer LS-55; вміст сухого знежиреного молочного залишку та лактози у зразках молока визначали на ультразвуковому аналізаторі молока “Екомілк-Бонд” (Болгарія). Пробопідготовка зразків молока для визначення триптофану здійснювалася згідно з ДСТУ ISO 13904:2008. Як показали дослідження, вміст триптофану у зразках молока українських виробників молочної продукції  коливається в межах 189,5–515,1 мг/л, що здебільшого узгоджується з літературними даними. Встановлено, що такі макрокомпоненти молока, як лактоза та сухий знежирений молочний залишок, не впливають на люмінесценцію триптофану. Залежності способу термообробки молока на вміст триптофану не виявлено. Очевидно, насамперед на вміст триптофану в молоці буде впливати загальний вміст білка у продукті

Kinetic study of carbon dioxide catalytic methanation over cobalt–nickel catalysts

Based on the data of the thermoprogrammed desorption and using mass-spectroscopic analysis of desorbed products and on the kinetic patterns of the methanation process for cobalt–nickel catalysts, we suggested a mechanism for the reaction which passes through forming intermediate formyl compounds: CHO*, HCOH*, and HCOOH*. Because of the high stability of the carbon dioxide molecule, the step of adding the first hydrogen atom is the limiting step. Such a mechanism is in good agreement with the proposed kinetic equations

Compensation Effect on Cu-Co-Fe Oxide Catalysts of CO Oxidation

The occurrence of compensation effect on massive and supported oxide catalysts of CO oxidation is shown. The explanation of compensation effect is offered based on the data on the surface state of the catalysts that are obtained by means of thermally programmed desorption method with mass spectrometric registration of the desorbed particles (TPD MS).Показано наявність компенсаційного ефекту на нанесених та масивних Cu-Co-Fe оксидних каталізаторах реакції окиснення СО. На основі даних про стан поверхні, одержаних методом термопрограмованої десорбції з мас-спектрометричним аналізом (ТПД МС), запропоновано пояснення компенсаційного ефекту.Показано наличие компенсационного эффекта на нанесенных и массивных Cu-Co-Fe оксидных катализаторах реакции окисления СО. На основании данных о состоянии поверхности, полученных методом термопрограммированной десорбции с масс-спектрометрическим анализом (ТПД МС), предложено объяснение компенсационного эффекта

Показники захворюваності на злоякісні новоутворення порожнини рота в Полтавській області (2001 - 2005)

Протягом останніх десяти років захворюваність на злоякісні новоутворення в Полтавському регіоні залишається стабільно високою і поділяє друге, третє, четверте місця в Україні. Відповідно до загальної захворюваності, вагомого значення набувають пухлини ротової порожнини, з якими часто зустрічаються лікарі-стоматологи. На жаль, незважаючи на профілактичні огляди лікарів-стоматологів, сімейних лікарів ця група хворих виявляється в занедбаному стані. Занедбаність досягає 60 - 70%; В течение последних десяти лет заболеваемость злокачественными новообразованиями в Полтавском регионе остается стабильно высокой и разделяет второе, третье, четвертое места в Украине. Согласно общей заболеваемости, большое значение приобретают опухоли ротовой полости, с которыми часто встречаются врачи-стоматологи. К сожалению, несмотря на профилактические осмотры врачей-стоматологов, семейных врачей эта группа больных оказывается в запущенном состоянии. Заброс достигает 60 - 70%; During the last ten years, the incidence of malignancies in the Poltava region remains consistently high and shares second, third, and fourth places in Ukraine. According to the general morbidity, oral tumors, which are often encountered by dentists, are of great importance. Unfortunately, despite the preventive examinations of dentists, family physicians this group of patients is in a state of disrepair. Neglect reaches 60 - 70%

AGE-DEPENDENT PATTERNS OF THE BASELINE CYTOKINE LEVELS IN UNSTIMULATED PERIPHERAL BLOOD SAMPLES

The cytokine levels in unstimulated peripheral blood samples differ in relation to age, living conditions (environmental situation, state of medical care, quality of life, etc). Thus, the essential task is to determine normal levels of peripheral blood cytokines for different age groups with respect to regional characteristics. This study aimed to investigate age-associated patterns of the baseline levels for some cytokines in unstimulated peripheral blood samples in healthy children and adults. The studies were carried out at the Laboratory of Clinical Immunology (Clinical and Diagnostic Centre, Yekaterinburg). Peripheral blood samples were taken in 149 healthy children aged from 7 months to 18 years. Group 1 was 7 to 12 months old (29 infants); group 2 was 1 to 3 years old (33 children); group 3 was 4 to 7 years old (29 children); 4th group was 8 to 14 years old (26 children); 5th group, 15 to 18 years old (32 children); and 6th group included 42 adults (19 to 45 years old). The concentrations of TNFα, IFNγ, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-17, and IL-18 in blood serum were determined by common ELISA technique using Vector-Best kits (Novosibirsk, Russia). Analysis of the data made it possible to identify various patterns of age-dependent changes of baseline levels for the determined cytokines: IL-2 showed an increase in concentration by the age of 1-3 years, stable contents up to 18 years, and decreased concentrations in adulthood. IFNγ was at zero levels in children and adolescents, followed by increased levels in adults. IL-4 and IL-6 showed consistently low levels in children and adolescents, with a decrease to zero levels in adult subjects. IL-18, TNFα were at maximal levels at the age of below 7 years followed by a decrease in concentration; IL-1β, IL-17 exhibited bimodal changes, with maximal contents at the age of 1-3 years, and repeated increase in adult age. Nearly stable baseline concentration was noted for IL-10, with a slight increase at 1-3 years, like as for IL-8, with a moderate increase at 15-18 years. For majority of analyzed cytokines, the maximal baseline contents in unstimulated peripheral blood samples were found in children aged 1-3 years. © 2021, RSI

Surgical Strategy in Patients with Complete Transposition of Internal Organs in Cancer of the Biliopancreatoduodenal Zone

Аim: to present two clinical cases of successful surgical treatment of patients with a combination of complete transposition of internal organs and cancer of the biliopancreatoduodenal zone.Key points. A 65-year-old man underwent gastropancreatoduodenal resection for cancer of the large duodenal papilla. In addition to the situs vicserum inversus, this patient revealed a special variant of vascular anatomy, namely: separate separation of the left and right hepatic arteries from the ventral trunk. A 70-year-old man, in addition to complete transposition of internal organs, had a combination of cancer of the terminal part of the common bile duct and heterotaxy syndrome in the form of polysplenia, aplasia of the hepatic segment of the inferior vena cava, agenesis of the dorsal pancreatic rudiment (“short” pancreas), intrapancreatic course of the right hepatic artery extending from the superior mesenteric arteries, rotational abnormalities of intestinal development. This patient underwent a total pancreatectomy. In both cases, the main difficulties in mobilizing the pancreatoduodenal complex arose due to anatomical disorientation and the absence of standard (familiar) topographic and anatomical landmarks for the surgeon.Conclusion. In all patients with tumors of the biliopancreatoduodenal zone, a detailed assessment of the vascular anatomy of this area is required before surgery, with the study of the course of the main visceral vessels and their large branches using multispiral computed tomography in vascular mode. If heterotaxy syndrome is suspected, additional examination is necessary to identify hidden developmental anomalies, which allows surgeons to be prepared for an unusual situation. Gastropancreatoduodenal resection or total pancreatectomy in situs viscerum inversus is a technically complex intervention and should be performed in large multidisciplinary medical institutions, and the operating team should have extensive experience in operations on the organs of the biliopancreatoduodenal zone