OBJECTIVE: More parameters have been used for more detailed description of mechanical properties of human hair as a fibre than in analogous studies. All measured samples were taken from five different locations on the heads of 60 women of varied age. METHODS: For each hair, the diameter was determined optically and then the test in the Deform Type 2 testing machine was carried out. Deformation curves were obtained by testing 10 mm long samples up to the rupture point at constant temperature, humidity and constant crossbar speed of 2 mm/min. The curves were processed with software for the calculation of mechanical parameters of the hairs. This specialized software has been designed by us for that purpose. Resulting values were arranged into tables and figures. RESULTS: As far as hair cross-section is concerned, it has been found that for the European population it appears to be rather higher - 86 μm - than indicated in formerly published texts. The 56 μm mentioned in the work of other authors has been observed only utterly exceptionally, in 0.3 % of the population. All quantities studied (except extensibility) display moderate to strong positive skewness in comparison to Gauss distribution. The most marked skewness is seen in the resilience. At the same time, this quantity displays the highest value of non-Gaussian distribution. The elasticity module of 2.3±0.6 GPa is three times lower than the one reported by other authors, yet according to the fact published in our work - which shows unambiguously that the thinner the hair, the higher elasticity module it displays - the value of 7.2 GPa for the 56 µm thick hairs is comparable and it confirms the hypothesis that the cortex, which is responsible for the mechanical strength of the hair, is contained in a higher ratio in thinner hairs. This similarly applies to the ultimate strength; the linearity limit is hard to compare with literature, as it almost does not appear there. CONCLUSION: By measuring 886 samples from the heads of 60 adult women of European type, it was possible to ascertain the current norm for a larger number of mechanical parameters of the hairs. Further merit of this work is the fact that the hairs were taken systematically from five well-defined places of the studied heads in equal count, which is an aspect formerly published works do not respect and they do not present the location of sampling.
- MeSH
- běloši MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mechanický stres * MeSH
- mladiství MeSH
- mladý dospělý MeSH
- pevnost v tahu fyziologie MeSH
- senioři MeSH
- vlasy, chlupy fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Tento článek představuje fenomén opakovaně volajících klientů v kontextu linek důvěry v ČR. Kromě principů a specifik práce na linkách důvěry, které vyplývají z povahy služby, se článek zabývá i nároky na pracovníky. Vše popisuje se zaměřením na zkoumaný fenomén opakovaně volajících klientů. Ten je nahlížen ve spojitosti stématem přístupu ke klientům, a to tak, jak je přístup formován kulturou organizace. Tento koncept reflektuje i dilemata, jež jsou s tématem opakovaně volajících klientů spojena. V článku jsou představeny výsledky kvalitativního výzkumu, který hledal odpověď na hlavní výzkumnou otázku: Jaký je přístup pracovníků k opakovaně volajícím klientům na pracovištích linek důvěry? Použitými metodami byly focus group, narativní rozhovory a analýza dokumentů. Výzkum vedl ke zjištění, že pracovníci využívají dva hraniční typy praxe, které jsme nazvaly lidský přístup a přístup profesionální. Pracovníci často oba přístupy kombinují na základě svých preferencí a kontextu konkrétní práce s klientem. Tyto vlivy shrnujeme a označujeme jako faktory: znalost klienta, možnosti pracoviště a možnosti pracovníka.
This article introduces the phenomenon of repeat callers in the context of the crisis lines in the Czech Republic. It refers either to principles and the specifity of crisis line work itself or requirements that are placed on worker. All is focused on phenomenon of repeat callers. It is seen according to approach to clients, with special regard to how it is shaped by the organization culture. This concept reflects the dilemmas that are associated with this topic. The article also include the results of qualitative research that has been doing into approach of crisis line workers to repeat callers by such research methods as focus group, narrative interviews and document analysis all of which led to answer the main research question: What is the approach of crisis line workers to repeat callers? The research led us to findings that workers use two border types of practice, which we call a human approach and a professional approach. Workers combine those approaches due to their preferences and particular context of casework. We summarise and call those influences as factors: acquitance of the client, possibilities of crisis line and possibilities of worker.
- MeSH
- horké linky * MeSH
- krizová intervence * MeSH
- lidé MeSH
- poradenství MeSH
- Check Tag
- lidé MeSH
OBJECTIVE: Hair quality and scalp characteristics are considered to be a significant marker of health. This marker is reflected in mechanical properties of hair. To investigate these properties, hair samples have been collected among women of different age and then analyzed. The thickness, Young's modulus of elasticity and ultimate strength limit were the main observed parameters. METHODS: The diameter of each hair has been measured using an optical microscope equipped with a digital camera. The hair was then clipped into the uniaxial tensile testing device. Each sample has been stretched to failure at a speed of 2 mm/min and force vs. elongation was recorded. The mechanical results were converted with respect to the diameter and Stress-Strain curve was obtained for each sample. In addition, all the analyzed samples were divided into two groups in dependence on the age, namely samples from women younger than 35 and over 35 years of age. All the measured parameters were statistically evaluated. RESULTS: Young's modulus, yield and elongation parameters showed no significant difference among samples. On the other hand there was a significant difference among the samples in ultimate strength values. Findings from group analysis showed that women under 35 years show about 5 times greater variability in hair strength than that of women above that age. CONCLUSION: The results of our study indicate that hair tendency to grow persists up to 30 years of age, then slowly decreases and then achieves a steady state around 60 years of age.
- MeSH
- biologické modely * MeSH
- dospělí MeSH
- elastografie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mechanický stres MeSH
- pevnost v tahu fyziologie MeSH
- pružnost * MeSH
- stárnutí fyziologie MeSH
- vlasy, chlupy anatomie a histologie růst a vývoj fyziologie MeSH
- zdravotní stav * MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Obyvatelé České republiky jsou každý den vystavováni různým situacím, ve kterých může být ohrožena jejich bezpečnost, zdraví, život nebo jejich majetek. Tyto situace musí být odpovídajícím způsobem řešeny nejen na úrovni obce nebo kraje, ale i na úrovni státu. Tato práce se zabývá bezpečnostním výzkumem v České republice, jeho definicí a zaměřením vycházejícím z dokumentů vydávaných vládou České republiky a odborníky, kteří se zajímají o toto téma. Přibližuje způsob analýzy a predikce bezpečnostních hrozeb na našem území a uvádí samotné hrozby, včetně jejich vysvětlení. Dále pak připomíná pojmy jako např. sekuritologie a obranná politika České republiky po roce 1989. Závěrem pak přibližuje několik konkrétních případů bezpečnostních hrozeb pro utvoření představy, a to zejména obchod s lidmi, korupční situace a hrozbu nedostatku vody. Finalizace článku se odehrává v době, kdy Českou republiku zasáhly téměř na celém území státu rozsáhlé povodně. Zkušenosti získané analýzou dat ukážou, jak realisticky byl zaměřen Bezpečnostní výzkum pro potřeby státu na období let 2010 až 2015 (BV II/1-VZ). Při jeho tvorbě se vycházelo z potřeb nových poznatků, postupů a metod jejich šíření a zejména jejich využití v bezpečnostní praxi při zajišťování významných úkolů spojených s vnitřní bezpečností státu a jeho obyvatel. Cíl programu byl stanoven na základě výzkumných potřeb jednotlivých rezortů a ostatních státních institucí, které v rámci svěřené působnosti plní úkoly v oblasti vnitřní bezpečnosti a ochrany obyvatelstva České republiky. Program také reflektuje návrh novely zákona o podpoře výzkumu a vývoje a byl zpracován jako program výzkumu a vývoje realizovaný veřejnou zakázkou.
Citizens of the Czech Republic are daily exposed to various situations in which their safety, health, life or property may be jeopardized. These situations must be adequately addressed not only at the level of municipalities and regions, but also at the state level. This work deals with the security research in the Czech Republic, its definition and focus, based on documents issued by the Government of the Czech Republic and professionals with an interest in the subject. It presents the way of analyzing and predicting security threats to our country and mentions the threats themselves, including their explanation. Furthermore, it mentions concepts such as securitology and defence policy of the Czech Republic after 1989. At the end, it clarifies several specific cases of security threats in order to get the picture, especially human trafficking, corruption situation and the threat of water shortage. Finalization of the article is happening at a time when almost the entire expanse of the Czech Republic was affected by extensive flooding. The experience gained by analyzing data show how realistic was the focus of security research for the State for the period 2010–2015 (BV II/1-VZ). Its elaboration was based on the needs of the new knowledge, practices and methods of distribution and in particular their use in practice in ensuring the security of important tasks related to the internal security of the state and its people. The objective of the program was determined on the basis of the research needs of individual ministries and other state institutions that fulfill the tasks in the area of internal security and protection of the population in the Czech Republic within the scope of their entrusted authority. The program also reflects an amendment to the promotion of research and development and has worked as a research and development program implemented by public tender.
- MeSH
- bezpečnost * normy zákonodárství a právo MeSH
- civilní obrana MeSH
- hodnocení rizik MeSH
- hromadné neštěstí prevence a kontrola MeSH
- katastrofy prevence a kontrola MeSH
- lidé MeSH
- obchod s lidmi prevence a kontrola MeSH
- podvod prevence a kontrola MeSH
- terorismus prevence a kontrola MeSH
- vládní programy * MeSH
- vytváření politiky * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
The article encompasses a possible concept of description of the structure of hair thickness distribution over women's heads. It is based on real data realized in Caucasian population and results in the necessity of introduction of several type groups of women's heads coverage. With an example included, it eliminates the possibility of the distribution to be random and that there are all of the possibilities of the distribution realized in the population, as well as that it could be reasonable to average these distinct type groups and look for the mean distribution in the population. The distribution structure is most likely contingent on genetics and is entrenched in some part of the DNA; it is not yet clear however, what intra-species advantages particular structure types could yield, while the correlation of the particular distributions with types of humans is subject to current research.
- MeSH
- antropometrie * metody MeSH
- běloši genetika MeSH
- experimenty na lidech MeSH
- genetické jevy MeSH
- hlava MeSH
- lidé MeSH
- mikroskopie metody využití MeSH
- skalp * anatomie a histologie růst a vývoj MeSH
- statistika jako téma MeSH
- vlasy, chlupy * anatomie a histologie růst a vývoj MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- práce podpořená grantem MeSH
The article deals with search for the material parameters that would be suitable for specification of human hair viscoelactic properties. These parameters have simultaneously satisfied an unambiguous differentiation between gravid and non-gravid women. Microscope was used to determine the hair thickness, a pull-test deformation device then to establish both the tearing resistance and relaxation curves, taken as a basis to determine values of Young’s modulus, relaxation time, shear yield point, breaking point, maximum elongation. Taken from the region around occipital condyla, ninety samples of uncolored female hair were placed under measurement. This study has shown that at least the parameters of yield point, diameter, and the second relaxation time are significantly affected by gravidity.
- Klíčová slova
- relaxační čas, Youngův modul, viskoclastický model vlasů, lidské vlasy,
- MeSH
- biologické modely MeSH
- elastografie metody využití MeSH
- lidé MeSH
- mikroskopie metody využití MeSH
- statistika jako téma MeSH
- těhotenství fyziologie metabolismus MeSH
- vlasy, chlupy fyziologie metabolismus růst a vývoj MeSH
- Check Tag
- lidé MeSH
- těhotenství fyziologie metabolismus MeSH
- ženské pohlaví MeSH
