Acrylamide (AA) is a highly reactive organic compound capable of polymerization to form polyacrylamide, which is commonly used throughout a variety of industries. Given its toxic effect on humans and animals, the last 20 years have seen an increased interest in research devoted to the AA. One of the main sources of AA is food. AA appears in heated food following the reaction between amino acids and reduced sugars. Large concentrations of AA can be found in popular staples such as coffee, bread or potato products. An average daily consumption of AA is between 0.3-2.0 μg/kg b.w. Inhalation of acrylamide is related with occupational exposure. AA delivered with food is metabolized in the liver by cytochrome P450. AA biotransformation and elimination result in formation of toxic glycidamide (GA). Both, AA and GA can be involved in the coupling reaction with the reduced glutathione (GSH) forming glutathione conjugates which are excreted with urine. Biotransformation of AA leads to the disturbance in the redox balance. Numerous research proved that AA and GA have significant influence on physiological functions including signal propagation in peripheral nerves, enzymatic and hormonal regulation, functions of muscles, reproduction etc. In addition AA and GA show neurotoxic, genotoxic and cancerogenic properties. In 1994, International Agency for Research on Cancer (IARC) classified acrylamide as a potentially carcinogenic substance to human., M. Semla, Z. Goc, M. Martiniaková, R. Omelka, G. Formicki., and Obsahuje bibliografii
Obesity is a serious health problem worldwide and many genes have been implicated in determination of obesity, but our knowledge of the genes responsible for individual differences in weight loss after physical intervention are poor. One of the candidate genes is a gene for angiotensin-converting enzyme (ACE) ant its insertion/deletion (I/D) polymorphism. We have analyzed the association between the ACE gene variant in intervened obese females. Twenty four unrelated healthy obese (BMI > 29.9 kg/m2, with abdominal type of obesity) premenopausal (age between 25 and 45 years) Czech Caucasian sedentary and non-diabetic females, pre-selected according the ACE I/D polymorphism (twelve II and twelve DD homozygotes) were studied in a medical research centre. They underwent 9 weeks intervention program (combination of the lowering of dietary intake to optimal level for the age and 3 times a week physical activity at fitness centre). The participants were supervised to sustain a heart rate of 65 % of maximum. Anthropometrical, biochemical parameters and body composition (Bodystat 1500) were analyzed before and after the intervention. Our study suggest, that in Czech Caucasian females I/D polymorphism within the ACE gene will have no major effect on weight loss. Interestingly, we have detected, that in obese females II genotype was associated with higher increase in basal metabolic rate (202 kcal per day) then in DD homozygotes (p<0.05), thus at least under some circumstances, this genetic variant may have an slight effect on BMI development., P. Suchánek ... [et al.]., and Obsahuje seznam literatury
Abstract: By action model, we understand any logic-based representation of effects and executability preconditions of individual actions within a certain domain. In the context of artificial intelligence, such models are necessary for planning and goal-oriented automated behaviour. Currently, action models are commonly hand-written by domain experts in advance. However, since this process is often difficult, time-consuming, and error-prone, it makes sense to let agents learn the effects and conditions of actions from their own observations. Even though the research in the area of action learning, as a certain kind of inductive reasoning, is relatively young, there already exist several distinctive action learning methods. We will try to identify the collection of the most important properties of these methods, or challenges that they are trying to overcome, and briefly outline their impact on practical applications., Abstrakt: Podle akčního modelu chápeme logickou reprezentaci efektů a předpokladů vykonatelnosti jednotlivých akcí v rámci určité domény. V kontextu umělé inteligence jsou tyto modely nezbytné pro plánování a cílené automatizované chování. V současné době jsou akční modely běžně ručně psány odborníky domény předem. Vzhledem k tomu, že tento proces je často obtížný, časově náročný a náchylný k chybám, má smysl nechat agenty seznámit se s účinky a podmínkami akcí z vlastních pozorování. I když je výzkum v oblasti akčního učení, jako určitý druh indukčního uvažování, relativně mladý, existuje již několik výrazných metod učení. Pokusíme se identifikovat sbírku nejdůležitějších vlastností těchto metod., and Michal Čertický
Fenoxycarb is an insecticide with a juvenile hormone mimicking effect, which disturbs metamorphosis in several insect species, including the neuropteran Chrysoperla carnea. Administration of different doses of fenoxycarb to third instar larvae causes a dose dependent inhibition of metamorphosis and cocoon spinning. When treated within 48 h of the last larval ecdysis, this insect shows a temporary inhibition of metamorphosis and cocoon spinning, which leads to a prolongation of the third larval instar. When treated after 60 h into the last instar, most of larvae were unable to metamorphose and spin a cocoon. Thus, C. carnea is most sensitive to this juvenoid in the period after 60 h into the last larval instar.