Oxidation and degradation of polyethylene in hip implants

The infrared absorption spectra of polyethylene samples from 13 used acetabular cups of hip prostheses retrieved from patients after different periods of use were studied. The presence of carbonyl compounds was observed in exploited polyethylene samples, confirming progressive oxidative degradation of polyethylene in biological environment

Vibration Control of Mechanical Systems - introduction to the problem

Príèiny vibrácií strojov sú rôznorodé a je ich ako analyzova. Ich analýza je ve¾mi dôleitá, nako¾ko vibrácie majú negatívne úèinky nielen na ivotnos, prevádzkyschopnos strojov, ale i na obsluhu strojov a ivotné prostredie. V èlánku sú charakterizované základné postuláty pasívnych a aktívnych metód pre analýzu, syntézu a návrhu útlmu vibrácií s vyuitím princípu riadených vibrácií. Vyuitie matematického modelovania mechanického systému a riadenia je predmetom súèasného simulaèného výskumu vo svete. Uvedená teória je úspene aplikovaná pre útlm, redukciu vibrácií strojov, rotorov zariadení, budov, komunikaèných prostriedkov

Reliability of retrospective assessment of the age of first menstruation

The age of the first menstruation is one of the indicators for assessing the course of puberty. It is also a sensitive indicator of the economic situation of individual professional groups or societies, and the low average age of menarche is widely recognized as a marker of society’s well-being. The aim of the study was to analyse the reliability of the retrospective method of assessing the age at menarche by comparing the results to the age obtained from continuous research. Data regarding the age at menarche came from longitudinal somatic development and physical fitness studies conducted between 1976 and 2022. In 2022, 47 women were examined. In continuous studies, the prospective method was used in the assessment of the age of first menstruation while in the 2004 and 2022 studies a retrospective method was applied. Only in 4 out of 47 women the age of the first menstruation declared in 2004 and 2022 (the women were 32–34 and 50–52 years old, respectively) was consistent with the one found in continuous studies. In other cases, there was a discrepancy between the age found in continuous studies and self-reported in 2004 or 2022 or between the age stated in 2004 and 2022. Of those women who were present for the 2022 study, 36 had information about the age of first menstruation from continuous studies and the age of menarche in 2004 was given. For this sample the arithmetic mean and the standard deviation of the age at menarche were calculated. It was found that the retrospective method often used in the assessment of the age of the first menstruation is not fully reliable, as the average discrepancy in the assessment ranged from nearly 1 month (0.05 years) to over 2 months (0.19 years) compared to the prospective method. Women surveyed in 2004 determined the age of the first menstruation more accurately compared to statements obtained 18 years later from the same women. This study suggests that long-term memory (LTM) of a significant life event of every woman is unreliable, as indicated by the difference in the declared age of the first menstruation of women examined in 2004 and 2022, which, in individual cases, was up to 3, 4 or 5 years

Erlang-based Software Update Platform for Mobile Devices

Growing computational power of mobile devices modifies existing approachesto data processing in large-scale sensor networks. Since sensors are no lon-ger limited to simple data acquisition tasks, such networks can be consideredcomplex geo-distributed data processing systems. Features and requirements ofsuch systems justify use of Erlang language and technology for programmingmobile devices. The technology provides several crucial features, including fault-tolerance, message-passing concurrency or hot-code loading. In this paper theproblem of software management in Erlang-based distributed systems is di-scussed. A mechanism for installing and upgrading Erlang applications usingoperating system package manager is described. A platform for updating so-ftware in large scale systems is presented

Polska, Ukraina, świat

Od Wydawcy: "Krakowska Szkoła Wyższa im. Andrzeja Frycza Modrzewskiego, największa niepubliczna szkoła wyższa w Małopolsce od początku swego powstania przywiązuje wagę do kontaktów z uczelniami zagranicznymi. Współpraca nawiązana z wieloma partnerami zagranicznymi nie tylko pozwoliła kadrze dydaktycznej i studentom Frycza nawiązać interesujące kontakty naukowe i biznesowe, wzbogacić księgozbiór o specjalistyczne publikacje, ale zaowocowała także wieloma cennymi programami. Współpraca Szkoły z Międzynarodowym Uniwersytetem REG I im. Akademika Stepana Demianczuka w Równem na Ukrainie - pierwszym partnerem zagranicznym, z którym umowę podpisano w grudniu roku 2001 - przebiega na wielu płaszczyznach (wymiana studentów i pracowników, udział w konferencjach, wspólne publikacje). Owocem jej je st też poniższa książka Polska, Ukraina, Świat pod redakcją Klemensa Budzowskiego i Anatolija Stiepanowicza Demianczuka, zawierająca dorobek naukowy pracowników obu uczelni."(...