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Purpose. In the paper there are described methods of two and three voltmeter readouts for insulation resistance periodic measurement in live DC and AC/DC IT networks. A new measuring method for AC/DC networks is proposed. Application of a novel algorithm for shortening of measurement cycle is explained. Methodology. All methods of two and three voltmeter readouts consist in connection of a resistor and measurement of mean value of network’s fixed point-to-ground voltages. Results. A new algorithm implemented in KDZ-3 device enables determination of steady-state voltage of a DC network’s pole much faster than in other exploited systems. Originality. In author’s modification of two voltmeter readouts method, line-to-ground voltage mean value is measured at AC side of AC/DC network. This innovation has not been applied for implementation of periodic insulation monitoring in AC/DC IT networks yet. Practical value. The use of author’s innovation will allow to execute measurements at AC side of AC/DC IT networks which might be necessary if rectifier’s output circuits are unavailable. Shortening of measurement cycle duration of two or three voltmeter readouts method’s is of great importance in networks with high capacitance.

Existing methods of indirect methods of electrical parameters of two-terminal elements determination exhibit a substantial limitation. Such parameters as resistance, inductance and capacitance are determined by means of current, voltage, power etc. measurement and calculation with relevant formulas. Accuracy of these procedures is lowered by internal impedance of applied meters. In the paper there are proposed few modifications of well-known indirect methods aimed at elimination of their errors.

Cystic fibrosis patients are characterised by disorders of fat-soluble vitamin absorption and bone metabolism. The aim of this study was to compare the effect of 3-month supplementation with calcitriol and cholecalciferol on calcium–phosphate balance in patients with cystic fibrosis. The study included 23 cystic fibrosis patients aged from 6 to 19 years. It was a crossover, placebo-controlled trial. There were 3 visits during which blood and urine were collected for analysis. The patients were treated with cholecalciferol (1,000 IU/day) or calcitriol (0.5 μg 1,25OHD) and placebo, and then received medications according to the cross-over regimen. The second visit took place after 3 months. The concentration of calcium, phosphate, parathyroid hormone and 25OHD were determined in blood serum; calcium/creatinine index was determined in urine. It was shown that after 3-month supplementation with calcitriol, the phosphate concentration decreased significantly, from 1.48 mmol/L (±SD 0.27 mmol/L) to 1.35 mmol/L (±SD 0.20 mmol/L) (p = 0.021). The calcium concentration increased significantly after 3 months of calcitriol treatment, from 3.50 mg/dL (±SD 2.60 mg/dL) to 4.35 mg/dL (±SD 3.35 mg/dL) (p = 0.001). The level of parathyroid hormone decreased significantly after 3 months of treatment with calcitriol, from 36.54 pg/mL (±SD 17.61 pg/mL) to 29.36 pg/mL (±SD 13.08 pg/mL) (p = 0.019). In the cholecalciferol supplementation group, there were no changes in phosphate, calcium or parathyroid hormone concentrations. Supplementation with either cholecalciferol or calcitriol did not affect serum 25OHD levels. In patients with cystic fibrosis, calcitriol supplementation at a dose of 0.5 μg is safe and has a more beneficial effect on the calcium–phosphate metabolism and bone metabolism than that of cholecalciferol at a daily dose of 1,000 IU.

Abstract Background Vitamin D plays an important role in inflammatory responses after antigen exposure. Interleukin-23 (Il-23) promotes Il-17-dependent inflammation during Pseudomonas aeruginosa (P. aeruginosa) pulmonary infection. We aimed to compare the ability of calcitriol and cholecalciferol to modulate the inflammatory response of the CF airways infected with P. aeruginosa. Methods This was a randomized, placebo-controlled, double-blind, cross-over trial. Twenty-three patients with CF (aged 6–19), chronically infected by P. aeruginosa were randomly assigned to: calcitriol group receiving 1,25(OH)2D 0,5 mcg daily or cholecalciferol group receiving cholecalciferol 1000 IU daily for three months. The levels of Il-23 and Il-17A in the exhaled breath concentrate (EBC) were measured. Calcium-phosphorus balance was also evaluated (serum concentration of calcium, phosphorus, 25OHD, parathormone (PTH) and calcium/creatinine ratio in urine). Data were analyzed using means of Stata/Special Edition, release 14.2. A level of P

The article presents the analysis of electrical signals and system reports of motor vehicles in which the mileage counter indication has been questioned under service conditions as compared to the vehicles mechanical wear and tear. The essence of the aforementioned deliberations is an attempt at determining the universal procedures allowing for obtaining data concerning the actual vehicle mileage. Search for the intended method results from many factors functioning on the used motor vehicle market. The major factor is the uncontrolled safety level on the roads among the road users and, equally important, financial frauds in the area of motor vehicle sales, as well as vehicle cost estimation by the insurance companies.

Operating parameters such as voltages, leakage, and ground fault currents are decisive for a correct and safe operation of low-voltage unearthed networks with diode rectifiers. The knowledge of the maximum possible values of these parameters is necessary for correct assessment of numerous hazards. So far, no simple methods for determining the highest levels of these parameters in AC/DC IT three-phase networks have been available. The paper presents a new approach to the evaluation of the variation ranges of diode rectifiers' voltages and currents with the help of Mathcad. [ABSTRACT FROM AUTHOR]

Operating parameters of electrical networks such as phase voltages, leakage and ground fault currents are decisive for safe operation of low-voltage unearthed networks with diode rectifiers. The knowledge of maximum possible values of network operating parameters is necessary for correct assessment of numerous hazards. So far no simple methods of determination of the highest levels of these parameters in AC/DC IT 3-phase networks have been available. The present paper reports a new approach to the evaluation of the variation ranges of the operating parameters of these systems using Mathcad. [ABSTRACT FROM AUTHOR]

Abstract Background Cystic Fibrosis newborn screening (CFNBS) is the optimal method to diagnose the disease during the asymptomatic period. The aim of the study was to determine how CFNBS affects long term clinical outcomes. Methods Data from infants who were born in Lodz Voivodship, referred to CF center as a part of CFNBS according to IRT/DNA protocol were compared to the data of children with established CF diagnosis before the start of NBS in Poland (Group CF, n = 52). Results In 37 children (during 151 referred infants) the diagnosis of CF was established due to CF NBS (CF NBS Group, n = 37). The average time of diagnosis was 1.59 month in Group CF NBS and 45.25 months in 52 children from Group CF. Pulmonary exacerbations occurred on average 4.2 times in Group CFNBS and they were hospitalized on average 0.5 times compared to Group CF – respectively 6.77 and 2.14 (p

The article presents an analysis of research on a series of passenger vehicles equipped with diesel and spark-ignition engines of modern generation. These studies show the attempt to determine the consistency of the measurement results presented by the electrical motor with respect to the external direct measurements determining the level ecological driving unit such as a gas analyzer. The premise of this material is to assess the suitability of the read actual parameters sent by the ECU as the data source the level of organic vehicle, for example. The test for diagnostic station with annual regular reviews. The inspiration for the material was the attempt to determine the sensitivity of the self-diagnosis system of the propulsion unit, which correctness of the diagnosis itself is one of the criteria of the positive periodic test guidelines.

Purpose. In the paper there are described few systems of insulation resistance continuous measurement using an imposed DC test signal delivered by diode rectifiers. Drawbacks of this technique are pointed out and ways of these shortcomings removal are proposed. Methodology. An improved version of measuring circuit based on a single-phase diode rectifier is presented. Application of logometric measuring devices is suggested. Results. A new insulation resistance continuous measuring system is insensitive to network voltages variation and asymmetry. Modified circuit enables also implementation of a simple device for alarming the monitored network’s insulation deterioration and/or earth-fault protection. Originality. Formulas describing performance of diode rectifiers under asymmetrical supply have not been available so far. Both innovations (i.e. single-phase diode rectifier and logometric meter) have not been applied widely for implementation of continuous insulation monitoring in live AC IT networks. Practical value. Use of both innovations will allow to eliminate unrequired dependence of measurement results on variable network voltages as well as their possible asymmetry. Exploitation of diode rectifier circuits for earth fault location is also possible.

Artykuł omawia rolę jednostek pomocniczych w największych polskich miastach jako ścieżki kariery polityków lokalnych. Badanie oparte jest na analizie danych z sześciu miast. Analiza składu społecznego grupy działaczy osiedlowych odwołuje się do prawa zwiększającej się dysproporcji sformułowanego przez Roberta D. Putnama. Na podstawie odwołania do kilku koncepcji teoretycznych w procesie selekcji uwzględnione są trzy etapy: autoselekcji, preselekcji (selekcji odgórnej) i selekcji oddolnej. Rola rad jednostek pomocniczych rozpatrywana jest w kontekście koncepcji inkubatora i respiratora kariery politycznej.