Effects of a single intraperitoneal administration of cadmium on femoral bone structure in male rats

<p>Abstract</p> <p>Background</p> <p>Exposure to cadmium (Cd) is considered a risk factor for various bone diseases in humans and experimental animals. This study investigated the acute effects of Cd on femoral bone structure of adult male rats after a single intraperitoneal administration.</p> <p>Methods</p> <p>Ten 4-month-old male Wistar rats were injected intraperitoneally with a single dose of 2 mg CdCl₂/kg body weight and killed 36 h after the Cd had been injected. Ten 4-month-old males served as a control group. Differences in body weight, femoral weight, femoral length and histological structure of the femur were evaluated between the two groups of rats. The unpaired Student's t-test was used for establishment of statistical significance.</p> <p>Results</p> <p>A single intraperitoneal administration of Cd had no significant effect on the body weight, femoral weight or femoral length. On the other hand, histological changes were significant. Rats exposed to Cd had significantly higher values of area, perimeter, maximum and minimum diameters of the primary osteons' vascular canals and Haversian canals. In contrast, a significant decrease in all variables of the secondary osteons was observed in these rats.</p> <p>Conclusions</p> <p>The results indicate that, as expected, a single intraperitoneal administration of 2 mg CdCl₂/kg body weight had no impact on macroscopic structure of rat's femora; however, it affected the size of vascular canals of primary osteons, Haversian canals, and secondary osteons.</p

Effects of dietary supplementation of nickel and nickel-zinc on femoral bone structure in rabbits

<p>Abstract</p> <p>Background</p> <p>Nickel (Ni) and zinc (Zn) are trace elements present at low concentrations in agroecosystems. Nickel, however, may have toxic effects on living organisms and is often considered as a contaminant. This study reports the effect of peroral administrated Ni or a combination of Ni and Zn on femoral bone structure in rabbits.</p> <p>Methods</p> <p>One month-old female rabbits were divided into three groups of five animals each. Group 1 rabbits were fed a granular feed mixture with addition of 35 g NiCl₂per 100 kg of mixture for 90 days. In group 2, animals were fed a mixture containing 35 g NiCl₂and 30 g ZnCl₂per 100 kg of mixture. Group 3 without administration of additional Ni or Zn served as control. After the 90-day experimental period, femoral length, femoral weight and histological structure of the femur were analyzed and compared.</p> <p>Results</p> <p>The results did not indicate a statistically significant difference in either femoral length or weight between the two experimental groups and the control group. Also, differences in qualitative histological characteristics of the femora among rabbits from the three groups were absent, except for a fewer number of secondary osteons found in the animals of groups 1 and 2. However, values for vascular canal parameters of primary osteons were significantly lower in group 1 than in the control one. Peroral administration of a combination of Ni and Zn (group 2) led to a significant decreased size of the secondary osteons.</p> <p>Conclusions</p> <p>The study indicates that dietary supplementation of Ni (35 g NiCl₂per 100 kg of feed mixture) and Ni-Zn combination (35 g NiCl₂and 30 g ZnCl₂per 100 kg of the mixture) affects the microstructure of compact bone tissue in young rabbits.</p

Testing of IDS model using several intrusion detection tools

The aim of this work is to provide set of selected tests on IDS model that would enlarge the functionality of intrusion detection systems. Designed model is using several IDS, which allows it to investigate larger bandwidth and capture more attacks. This system consists of central master node and devices on which the intrusion detection systems are. The tests were designed with the attribute of repeatability and universality. They are divided into five categories which explore specific attributes of intrusion detection system

Lifetime prediction of propellants according to NATO standards

This work presents the process of lifetime prediction of propellants according to new NATO standards. It shows the examples of lifetime prediction of selected nitrocellulose based propellants that are used in the ammunition of Armed Forces of Slovak republic

Sex differences in radioulnar contrasts of the finger ridge counts across 21 human population samples

Aim: The aim of the present study was to demonstrate the existence of uniform sexual dimorphism in some radioulnar contrasts between different finger ridge counts within the same hand in a large set of populations, thus confirming the universal nature of this dimorphism in humans.Subjects and methods: We analysed individual finger ridge counts (10 values on each hand) of both hands from archival sources (mainly the Brehme-Jantz database). In total, these included 4412 adults from 21 population samples covering all permanently inhabited continents and encompassing very different and geographically distant human populations. We calculated the contrasts (differences) of all pairs of ridge counts (45 per hand) and used diverse methods to assess the direction and degree of dimorphism of them across all population samples.Results: The highest sexual dimorphism was observed for nine contrasts involving the ridge count of the dermatoglyphic pattern on the radial side of the second finger of the right hand (R2r). Among these contrasts, we then found four that had the same direction of dimorphism in all 21 populations. The most dimorphic was the contrast R1rR2r – the difference between the ridge count of the radial side of the thumb and the radial side of the index finger.Discussion: Thus, these dermatoglyphic traits can be further investigated as potential markers of prenatal sex differentiation from ca. 10th week of intrauterine development. However, it will be useful to address the detailed factors and mechanisms for differences in the degree of dimorphism of these traits in different populations

A characteristic of selected properties of vulcanised rubber elements used on the “Izabel” inland vessel

Vulcanised rubber as a complex system is made from the basic component being virgin rubber and various components amounting to 10-15 per cent or even more. The material gains its most valuable properties in the final phase of processing i.e. vulcanisation. In mechanical as well as automotive engineering it is important for vulcanised rubber to be resistant to grease, oil and fuel in high operating temperatures. Being one of the very valuable isolation materials, vulcanised rubber is also characterized by dielectric and elastic properties as well as distinguished resistance to operating conditions (high/low temperature, weather conditions). All the above mentioned applications of vulcanised rubbers are also found in the shipyard industry. Their use is also very much predicated on the properties such as: ability to attenuate mechanical vibrations, high elasticity, considerable elastic deformability under static and dynamic loads, low permeability of water and gas, resistance to various chemicals, and other. The purpose of this article was to determine the hardness of vulcanised rubber samples obtained from various places on the “Izabel” inland barge. The scope of the study covered sampling and preparing the samples for testing (i.e. cleaning and degreasing the samples). Then, the hardness of the samples was measured using the Shore hardness test. The first part of the article presents the general concept of vulcanised rubber, its main components, properties, applications, and ageing. The second part focuses on the research scope and measuring the hardness of vulcanised rubber samples obtained from the “Izabel” inland barge. vulcanised rubber, hardness, ageing, wear and tear wulkanizowanej gumy, twardość, starzenie się, zużyci

Research of individual factors affecting the engine power while a passenger car operation

Power of any kind of a car engine is considered to be one of the basic factors in order to choose or assess vehicles equipment or its appropriateness. It influences several operation properties including car maximum velocity, car acceleration, etc. A car producer shall issue the data about an engine power of a car in a form of its technical attributes, nevertheless an engine power specification is also stated in a car registration certificate. Engine power may be defined as the maximum engine output at given revolutions of an engine, i.e. maximum engine power. In most of cases of cars operation, various situations may occur in order to specify the maximum engine power value. This study addresses the issue of determining individual factors affecting the engine power while a passenger car in operation, i.e. testing the engine power on the single roller bench and related particular analysis