scholarly journals Rational Possibility of Generating Power Laws in the Synthesis of Cam Mechanisms

2021 ◽  
Vol 21 (2) ◽  
pp. 184-190
Author(s):  
B. I. Paleva-Kadiyska ◽  
R. А. Roussev ◽  
V. В. Galabov
Keyword(s):  
Power Laws ◽  
Mathematical Induction ◽  
Power Functions ◽  
Study Objective ◽  
Laws Of Motion

Introduction.The generation of polynomial power laws of motion for the synthesis of cam mechanisms is complicated by the need to determine the coefficients of power polynomials. The study objective is to discover a rational capability of generating рower law swith arbitrary terms number under s with an rbitrary number of terms under the synthesis of cam mechanisms.Materials and Methods.A unified formula for determining the values of coefficients of power polynomials with any number of integers and/or non-integer exponents is derived through the so-called transfinite mathematical induction.  Results.A unified formula for determining the values of coefficients, which gives correct results for any number of even and/or odd exponents, is presented. The correctness of the derived formula is validated by the results on the multiple checks for different numbers, even and odd values of the exponents of quinquinomial and hexanomial power functions.  Discussion and Conclusions. A unified formula for determining the values of coefficients of power polynomials makes it possible to rationally define the laws of motion without finite and infinite spikes in the synthesis of elastic cam-lever systems. This provides a rational determination of the laws of motion without finite and infinite spikes in the synthesis of elastic cam-lever systems, and simple verification of the accuracy of the results obtained. The functions are particularly suitable for the synthesis of polydyne cams, as well as cams, since one polynomial can be used throughout the entire geometric mechanism cycle.

Determination of As, Cd, Ni and Pb in PM10 – comparison of different sample work-up and analysis methods/Bestimmung von As, Cd, Ni und Pb in PM10 – Vergleich verschiedener Probenaufbereitungs- und Analysenverfahren

Gefahrstoffe ◽  
2020 ◽  
Vol 80 (06) ◽  
pp. 227-233 ◽  
Author(s):  
I. Beslic ◽  
J. Burger ◽  
F. Cadoni ◽  
D. Centioli ◽  
I. Kranjc ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Metal Concentration ◽  
Inductively Coupled Plasma ◽  
Ambient Air ◽  
Power Functions ◽  
Joint Research ◽  
Inductively Coupled ◽  
Target Values ◽  
Work Up

In 2015 the European Joint Research Center (JRC) for air quality in Ispra, Italy, carried out an intercomparison for the determination of PM10 and PM2.5 in ambient air. Five laboratories also analyzed the content of heavy metals (arsenic, cadmium, lead and nickel) in PM10 from filter samples collected during the intercomparison. Thus, all steps from sampling in the field to instrumental quantification of heavy metals in the laboratory could be statistically analyzed. The different techniques of sampling and sample work-up had no significant influence on the analysis results. However, the method of instrumental analysis strongly influenced them: The results of laboratories using the Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) coincided well in most cases. For laboratories using the Energy Dispersed X-Ray Fluorescence (ED-XRF) technique the uncertainty of the results strongly depended on the metal concentration. For cadmium the concentrations generally were too low for analysis by ED-XRF, for arsenic, lead and nickel the relative uncertainties decreased exponentially with increasing concentrations. The relation between metal concentration and the relative uncertainty of analysis results could be described as power functions. Analysis of lead and nickel by ED-XRF is well possible in the range of the EU limit and target values for these metals.

Surgical treatment of the tumors of the fourth ventricle through telovelar approach

2018 ◽  
Vol 20 (2) ◽  
pp. 8-16 ◽  
Author(s):  
A. V. Kalinovskiy ◽  
S. V. Chernov ◽  
A. V. Zotov ◽  
A. R. Kasymov ◽  
E. V. Gormolysova ◽  
...  
Keyword(s):  
Surgical Treatment ◽  
Brain Stem ◽  
Fourth Ventricle ◽  
Radical Resection ◽  
Adult Patients ◽  
Study Objective ◽  
Results Of Treatment ◽  
Telovelar Approach ◽  
Ventricular Tumors

The study objectiveis analysis of surgical treatment results of adult patients with tumors of the fourth ventricle and determination of predictors of unsuccessful outcomes.Materials and methods.In the present study we review results of treatment of 33 adult patients with tumors of the fourth ventricle, which were operated via telovelar approach in Federal Neurosurgical Center (Novosibirsk). The most common symptoms included hydrocephalus (54.5 %), cerebellar dysfunction (33.3 %), cranial nerve deficits (30.3 %). The tumor size was more than 40 mm in 22 cases (66.7 %). The brain stem invasion was occurred in 21 cases (63.6 %).Results.23 tumors were removed totally (69.7 %). Hydrocephalus was regressed in 17 cases (94.5 %). Cerebellar mutism did not occur in any patient. Conclusion.Predictors of poor result may be brain stem invasion, non-radical resection of tumor and preoperative hydrocephalus. We suggest, that the preoperative hydrocephalus should not been operated in the most cases of the fourth ventricular tumors.

scholarly journals Pharmacokinetics of Pantoprazole and Pantoprazole Sulfone in Goats After Intravenous Administration: A Preliminary Report

2021 ◽  
Vol 8 ◽  
Author(s):  
Joe S. Smith ◽  
Jonathan P. Mochel ◽  
Windy M. Soto-Gonzalez ◽  
Rebecca R. Rahn ◽  
Bryanna N. Fayne ◽  
...  
Keyword(s):  
Intravenous Administration ◽  
Half Life ◽  
Plasma Clearance ◽  
Primary Study ◽  
Pharmacokinetic Parameters ◽  
Pharmacokinetic Data ◽  
Study Objective ◽  
Elimination Half Life ◽  
Elimination Half

Background: Ruminant species are at risk of developing abomasal ulceration, but there is a lack of pharmacokinetic data for anti-ulcer therapies, such as the proton pump inhibitor pantoprazole, in goats.Objective: The primary study objective was to estimate the plasma pharmacokinetic parameters for pantoprazole in adult goats after intravenous administration. A secondary objective was to describe the pharmacokinetic parameters for the metabolite, pantoprazole sulfone, in goats.Methods: Pantoprazole was administered intravenously to six adult goats at a dose of 1 mg/kg. Plasma samples were collected over 36h and analyzed via reverse phase high performance liquid chromatography for determination of pantoprazole and pantoprazole sulfone concentrations. Pharmacokinetic parameters were determined by non-compartmental analysis.Results: Plasma clearance, elimination half-life, and volume of distribution of pantoprazole were estimated at 0.345 mL/kg/min, 0.7 h, and 0.9 L/kg, respectively following IV administration. The maximum concentration, elimination half-life and area under the curve of pantoprazole sulfone were estimated at 0.1 μg/mL, 0.8 h, and 0.2 hr*μg/mL, respectively. The global extraction ratio was estimated 0.00795 ± 0.00138. All animals had normal physical examinations after conclusion of the study.Conclusion: The reported plasma clearance for pantoprazole is lower than reported for foals, calves, and alpacas. The elimination half-life appears to be < that reported for foals and calves. Future pharmacodynamic studies are necessary for determination of the efficacy of pantoprazole on acid suppression in goats.

scholarly journals THE DETERMINATION OF CHRISTIAN HOLIDAYS IN INDONESIA BY USING MEEUS ASTRONOMICAL

Dialog ◽  
2016 ◽  
Vol 39 (2) ◽  
pp. 131-138
Author(s):  
Admiral Musa Julius ◽  
Rukman Nugraha ◽  
I Putu Pudja
Keyword(s):  
Full Moon ◽  
Gregorian Calendar ◽  
Accurate Calculation ◽  
Study Objective ◽  
Vernal Equinox ◽  
Time Marker ◽  
The Future

Astronomically, Easter falls on the first Sunday following the first full moon after the vernal equinox. In Indonesia, Christian holidays including Easter are regulated by the Ministry of Religious Affairs based on the recommendation of Indonesian Church Union (PGI) and Bishops Conference of Indonesia (KWI). This study objective is to formulate a simple time marker by using Meeus Astronomical Algorithm to determine Christian holidays in Indonesian Gregorian calendar. Another objective is to evaluate the Christian holidays on Indonesian calendar between 1960 and 2015. Finally, this study would also provide prediction for future Christian holidays. This study finds out that the Christian holidays on Indonesian calendar are proven as methodologically accurate. It indicates that Meeus Astronomical Algorithm can produce accurate calculation for determining Christian holidays in Indonesia in the future. KEY WORDS:Meeus astronomical algorithm, christian holidays, Indonesian calendar

scholarly journals Changing the Contact Wetting Angles when Adding Surface-Active Substances to Washing Solutions

2019 ◽  
pp. 295-305
Author(s):  
Nikolay V. Byshov ◽  
Ivan A. Uspensky ◽  
Victor V. Alekseev ◽  
Ivan V. Fadeev
Keyword(s):  
Functional Dependence ◽  
Statistical Processing ◽  
Wetting Angle ◽  
Power Functions ◽  
Limit Value ◽  
Physico Chemical ◽  
Washing Process ◽  
Contact Wetting Angle ◽  
Surface Active

Introduction. The technological processes of the washing contaminations are largely determined by the nature of the surface being cleaned, the contamination type and the environment, in which the cleaning is carried out. The efficiency of the process depends on the contact of the detergent with the surface being washed. The wetting characteristic is a contact angle, which is a measure of the relative attraction of a liquid to a solid and to liquid itself. The physico-chemical activity of the washing medium determines the costs and, consequently, the optimal parameters of the washing process. In addition, it affects the increase in corrosion resistance. Therefore, it is relevant to determine the functional dependence of the contact wetting angle on the concentration of various combinations of surfactants. Materials and Methods.The determination of the contact wetting angle is based on the statistical processing of a photograph of a detergent drop on a horizontal surface by a specially created program that allows obtaining an array of data to describe the shape of a drop from which the contact wetting angle is calculated. The values of the contact wetting angle were measured when varying concentrations of such synthetic detergents as Labomid-203, MS-8, ML-51, etc. Multiplicative power functions connecting the magnitude of the contact wetting angle with surfactant concentrations were obtained. Results. The studies has shown that an increase in the concentration of potassium monoborate with Labomid-203 by 1 % leads to a decrease in the contact wetting angle by 0.54 %; potassium monoborate with MS-8 by 0.78 %; and potassium monoborate with ML-51 by 0.48 %, the function shows a decreasing return to an increase in concentration. Discussion and Conclusion. In all the considered cases, a decreasing return of the magnitude of the contact wetting angle to an increase in the concentration of surfactants was established, regardless of which combination of substances was used. That is, the investigated concentrations of surfactants exceeded the limit value when they gave an increasing return to the increase in their content in the washing solution. Thus, it can be concluded that for the considered combinations the percentage of surfactant is redundant.

scholarly journals Obesity as a factor in spermatogenesis disorders (experimental study)

2020 ◽  
Vol 21 (2) ◽  
pp. 36-43
Author(s):  
A. A. Artamonov ◽  
S. V. Bogolyubov ◽  
T. I. Eliseeva ◽  
O. B. Pozdnyakov ◽  
A. V. Astakhova
Keyword(s):  
Total Cholesterol ◽  
Dna Fragmentation ◽  
Control Group ◽  
Sperm Dna Fragmentation ◽  
Study Objective ◽  
Diet Induced Obesity ◽  
White Rats ◽  
Sperm Dna ◽  
Significant Difference

Introduction. In recent years, the effects of obesity on male fertility have been extensively investigated. The results of existing studies are extremely contradictory.The study objective was to determine the effect of obesity on the male reproductive system using the biological model of laboratory rats as an example.Materials and methods. In vivo modeling of diet-induced obesity. The study was conducted on 22 laboratory sexually mature white rats weighing 140–160 g. The animals were divided into two groups: 1 control (10 animals) and 2 rats with diet-induced obesity (12 animals). After 12 weeks, the animals were removed from the experiment. All rats underwent: calculation of the Lee index (body mass index in rats), determination of the concentration and viability of spermatozoa in a suspension of sperm from the epididymis, determination of glucose level of total cholesterol and triglycerides in the blood, study of sperm DNA fragmentation, histological examination testis: calculating the crosssectional area of the seminiferous tubule; determination of the number of non-functioning tubules and tubules with desquamated spermiogenic epithelium; determination of the average spermatogenesis index.Results. In the study groups there were no differences in glucose and total cholesterol levels. However, a statistically significant, significant difference in the level of triglycerides in the blood was revealed. The concentration of sperm and their viability in the studied groups did not differ. The level of sperm DNA fragmentation in the experimental group is significantly higher than in the control group (31.5 ± 10.1 and ± 1.4 %, respectively, p <0.05). Morphometric evaluation of histological preparations did not establish differences in the cross-sectional area of the seminiferous tubules and the average spermatogenesis index in the studied groups. In rats with obesity, compared with the control group, significantly more non-functioning tubules (2.9 ± 0.3 and 8.4 ± 0.3; p <0.05) and tubules with desquamated spermatogenic epithelium (1.8 ± 0.3 and 8.8 ± 0.5; p <0.05).Conclusion. Diet-induced obesity causes impaired spermatogenesis, and damage to the sperm genetic material in male white rats.

ETHANOL RECOVERY FROM PROPOLIS PRODUCTION WASTE USING ADSORPTION DISTILLATION METHOD

2021 ◽  
pp. 13-17
Author(s):  
MUHAMAD SAHLAN ◽  
LINDATIANA YULISTIONO ◽  
ASHADI SASONGKO ◽  
APRILIANA CAHYA KHAYRANI ◽  
KENNY LISCHER ◽  
...  
Keyword(s):  
Silica Gel ◽  
Synthetic Zeolite ◽  
Distillation Method ◽  
Adsorption Method ◽  
Study Objective ◽  
Ethanol Content ◽  
Initial Identification ◽  
Ethanol Recovery ◽  
By Products

Objective: This study objective to compare two adsorbents in the ability to recover ethanol in the propolis production by-product. Methods: Research methods include initial identification of the compound content in ethanol by-products of propolis production with GC/MS and determination of ethanol levels by GC-FID. The process of increasing ethanol content is carried out by the adsorption distillation method; the adsorbent used are synthetic zeolite 3A and white silica gel which has activated with the furnace. Results: The result obtained from the study is the initial ethanol content 27.5%. After the ethanol recycle process using synthetic zeolite 3A 30, 60, and 90 grams, it was obtained content 82.3%, 87.1%, and 90.9%. By using 30, 60, and 90 grams silica gel, it was obtained content 72.0%, 79.2%, and 82.2%. Conclusion: Based on these results it can be concluded that the ethanol content of the by-products of propolis production has been successfully increased by the distillation adsorption method with synthetic zeolite 3A 90 grams as the best result. The ethanol which recycling with this formulation has the characteristic odor of ethanol, which is very strong and does not has the characteristic odor of propolis.

Morphological studies of pollen grains of the Polish endemic species of the genus Rubus (Rosaceae)

Biologia ◽  
2012 ◽  
Vol 67 (1) ◽  
Author(s):  
Dorota Wrońska-Pilarek ◽  
Andrzej Jagodziński ◽  
Tomasz Maliński
Keyword(s):  
Pollen Morphology ◽  
Pollen Grains ◽  
Grain Morphology ◽  
Pollen Grain ◽  
Study Objective ◽  
Mean Values ◽  
Morphological Studies ◽  
Exine Sculpture ◽  
Pollen Grain Morphology

AbstractThe pollen of six taxa of the genus Rubus endemic to Poland (R. capitulatus, R. chaerophylloides, R. ostroviensis, R. posnaniensis, R. seebergensis and R. spribillei)was studied using light and scanning electron microscopy. The study objective was to extend the knowledge of the species pollen morphology and to investigate whether pollen morphology may help to taxonomically distinguish a very rare bramble species. Study material was derived from six natural localities where the species occur in the Wielkopolska region (Poland). Ten quantitative pollen grain features were analysed as well as the following qualitative ones: outline, shape, type of bridge and exine sculpture. Only mature, correctly formed pollen grains (30 per specimen) were measured and 180 pollen grains were examined in total. It was found that R. capitulatus and R. seebergensis had the highest mean values of P, E and Le features. In addition, pollen grains of R. capitulatus were most flattened (mean P/E ratio equals 1.14), while those of R. seebergensis were most elongated (mean P/E ratio equals 1.27). R. spribillei was the only species with striae of similar width as muri, whereas striae in the remaining species were wider. R. chaerophylloides and R. posnaniensis were characterised by specific, similar exine sculpture. Nevertheless, it should be stated that differences between pollen features of the species studied are so small and the variability of these features are so large that it is difficult to clearly identify the species studied. Therefore, pollen grain morphology can serve only as an auxiliary feature for the determination of these species.

scholarly journals PREGNANCY PLANNING. VITAMIN D DEFICIT – INFERTILITY, CORRECTION OF VITAMIN D DEFICIT

2017 ◽  
pp. 46-47
Author(s):  
O. I. Yazykova ◽  
E. G. Khilkevich
Keyword(s):  
Vitamin D ◽  
Menstrual Cycle ◽  
Reproductive Health ◽  
Vitamin D Deficiency ◽  
Study Objective ◽  
Pregnancy Planning ◽  
Adequate Level ◽  
Foreign Literature ◽  
Study Results

Study objective. To study the efficacy of the drugs vitamin D at the stage of planning of pregnancy in women with infertility of various etiologies, according to domestic and foreign literature.Materials and methods. We conducted a search of the literature sources by the keywords “vitamin D”, “infertility”, “pregravid preparation” in domestic and foreign databases: elibrary, Medline/PubMed, Embase, CINAHL. 23 sources were selected.Study results. Vitamin D plays an important role in the regulation of the menstrual cycle and the reproductive health of women. The prevalence of vitamin D deficiency among women with infertility of various etiologies reaches 69%. It is vital to achieve an adequate level of vitamin D in a woman’s body and to prevent its deficiency.Conclusion. For all women with infertility at the stage of preparation it is recommended to conduct assessment of adequacy of vitamin D by determination of 25(OH)D in serum and correction of its deficit to achieve levels of 25(OH)D more than 30 ng/ml. 

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