A method for estimation of elastic wave velocity anisotropy based on ultrasonic sounding data during rock-sample loading was developed. The subject matter of the method is approximation of ultrasonic sounding data by triaxial velocity ellipsoid. The applicability of proposed method was verified on investigation of anisot ropic rock samples. Laboratory loading of migmatite samples was realized under various mutual orientations between acting force direction and rock foliation - perpendicular, parallel and under 45°. P-ve velocity of ultrasound waves was monitored by 8 sensors network. The velocity ellipsoid was computed and changes of sizes and waorientation its main axes during loading were analyzed for separate experiments with regard to loading level. It was found, that independently to mutual orientation between rock foliation and loading direction, the minimum velocity vector turns to perpendicular direction to final rupture plane and maximum velocity vector turns to the plane of final rupture., Matěj Petružálek, Jan Vilhelm, Tomáš Lokajíček and Vladimír Rudajev., and Obsahuje bibliografické odkazy
Photosynthetic parameters including net photosynthetic rate (P N), transpiration rate (E), water-use efficiency (WUE), and stomatal conductance (g s) were studied in indoor C3 plants Philodendron domesticum (Pd), Dracaena fragans (Df), Peperomia obtussifolia (Po), Chlorophytum comosum (Cc), and in a CAM plant, Sansevieria trifasciata (St), exposed to various low temperatures (0, 5, 10, 15, 20, and 25°C). All studied plants survived up to 0°C, but only St and Cc endured, while other plants wilted, when the temperature increased back to room temperature (25°C). The P N declined rapidly with the decrease of temperature in all studied plants. St showed the maximum P N of 11.9 μmol m-2 s-1 at 25°C followed by Cc, Po, Pd, and Df. E also followed a trend almost similar to that of P N. St showed minimum E (0.1 mmol m-2 s-1) as compared to other studied C3 plants at 25°C. The E decreased up to ≈4-fold at 5 and 0°C. Furthermore, a considerable decline in WUE was observed under cold stress in all C3 plants, while St showed maximum WUE. Similarly, the g s also declined gradually with the decrease in the temperature in all plants. Among C3 plants, Pd and Po showed the maximum g s of 0.07 mol m-2 s-1 at 25°C followed by Df and Cc. However, St showed the minimum gs that further decreased up to -4-fold at 0°C. In addition, the content of photosynthetic pigments [chlorophyll a, b, (a+b), and carotenoids] was varying in all studied plants at 0°C. Our findings clearly indicated the best photosynthetic potential of St compared to other studied plants. This species might be recommended for improving air quality in high-altitude closed environments., S. M. Gupta, A. Agarwal, B. Dev, K. Kumar, O. Prakash, M. C. Arya, M. Nasim., and Obsahuje seznam literatury
The majority of the conservation strategies for threatened dragonflies are designed to protect only their aquatic habitats. Sympetrum depressiusculum is a species threatened not only by the destruction of its aquatic habitats but also by its association with a specific terrestrial environment. In this study, we aimed to identify the key elements of the terrestrial environment of adult S. depressiusculum. We used generalized linear mixed models to determine habitat preferences of adults and the particular features of habitat patches, such as vegetation cover, vegetation structure and the availability of potential prey. Our results indicate that S. depressiusculum adults preferred mainly riparian vegetation but beyond ponds they utilized only certain terrestrial habitats (abandoned fields, meadows, forest clearings). Adults responded positively to habitat patches with a high cover of vegetation and suitable vegetation structure. Adult abundance was affected also by the distance of patches from the natal site. In an agricultural landscape, the availability of such habitat patches may be limited and could influence the abundance and distribution of this species. We suggest that conservation efforts for this species should not only focus on the larval environment but also include suitable surrounding terrestrial habitats. Effective management around natal sites should concentrate on maintaining a heterogeneous landscape, which is extensively managed (e.g. leaving several fields fallow, maintaining managed hay meadows)., Michal Hykel, Filip Harabiš, Aleš Dolný., and Obsahuje bibliografii
Waterlogging is one of the critical factors controlling the distribution, regeneration, and survival of vegetation in wetlands. Here, we tested the hypothesis that Mitragyna parvifolia (Roxb.) Korth. and Syzygium cumini Keels, inhabiting the Keoladeo National Park, a Ramsar wetland (Bharatpur, India), are tolerant to waterlogging. The morphological and photosynthetic variables of four-month-old seedlings subjected to waterlogging, along with the concentrations of macroand micronutrients, were examined. After 35 days, treatment was halted due to high mortality of S. cumini seedlings in contrast to that of M. parvifolia seedlings. Significant declines in most of the studied variables were observed in both species when compared with their respective controls. In addition, M. parvifolia seedlings developed adventitious roots and lenticels and showed an increased root biomass. Based on the results, we concluded that adaptive traits displayed by M. parvifolia seedlings facilitate its tolerance to waterlogging in contrast to S. cumini seedlings., A. Bidalia, Z. Okram, M. Hanief, K. S. Rao., and Obsahuje bibliografii
The effect of water stress on the gas exchange (CO2, H2O), distribution, water potential (T*), membrane permeability and chlorophyll content was studied in two maize hybrids, of the high and low drought tolerance, in the vegetative phase of growth. Diťferences in the responses to drought between both hybrids were clearly marked. After 5 d of drought the decrease in the net photosynthetic rate uptake and losses, transpiration rate (E) and increase of stomata resistance (r^ were greater in the drought-resistant hybrid than in the drought-susceptible one. On the contrary, after 10 or 15 d of drought, the decrease of and 'P in whole seedlings was greater in the susceptible hybrid than in the resistant one. Significant differences between hybrids were also observed in the accumulation of *'^C, the membrane permeability and the chlorophyll content. For all treatments the amount of carbon accumulation in roots of the resistant hybrid increased, while that of the susceptible one decreased. In the drought-resistant hybrid we observed a greater chlorophyll stability and a smaller damage of cell membranes than in the sensitive one.
Dyslipidemia is the risk fact or of cardiovascular disease, but the relationship between the plasma triglyceride (TG) levels and total/cardiovascular mortality has not yet been analy zed in Slavs. The aim of our study was to analy ze the association between the fasting TG levels and all- cause/cardiovascular mortality. We have examined 3,143 males and 3,650 females, aged 58.3±7.1 years. 729 deaths (274 cardiovascular deaths) have been registered during up to 11.8 years of follow -up. Age -sex adjusted all -cause mortality was higher in individuals with TG values 3.01 -4.00 mmol /l (HR 1.37, 95 % CI 1.02- 1.83, P=0.035) and over 4.00 mmol /l (HR 1.66, 95 % CI 1.21 -2.27, P=0.002) when compared with a reference group (TG 1.41 -1.80 mmol /l). Elevated risk remains significant when adjusted for education, marital status and unemployment. When further adjusted for smoking, BMI and dyslipidemia interventions, HR for those in above 4.00 mmol/l group decreas ed (1.42, P=0.04). The results have been similar when cardiovascular mortality has been examined, however, results reached statistical significance only for the TG over 4.0 mmol /l (P=0.028). Our results confirmed that enhanced plasma levels of plasma triglycerides are dose dependently associated with increased risk of all- cause mortality, however, it s eems that individuals with TG values 1.8 -3.0 mmol /l are not in higher risk of death., H. Pikhart, J. A. Hubáček, A. Peasey, R. Kubínová, M. Bobák., and Obsahuje bibliografii
The aim of this study was to evaluate the association of A1166C polymorphism in angiotensin II type 1 receptor (AT1R) gene with baroreflex sensitivity (BRS in ms/mm Hg; BRSf in mHz/mm Hg) in man. BRS and BRSf were determined by a spectral method in 135 subjects (19-26 years) at a frequency of 0.1 Hz. Genotypes were detected by means of polymerase chain reaction and restriction analysis using enzyme DdeI. We compared BRS and BRSf among genotypes of this polymorphism. The frequency of genotypes of AT1R A1166C polymorphism was: 45.9 % (AA, n=62), 45.9 % (AC, n=62), 8.2 % (CC, n=11). Differences in BRS (p<0.05) and BRSf (p<0.01) among genotypes of this single nucleotide polymorphism were found (Kruskal-Wallis: BRS - AA: 7.9±3.3, AC: 8.6±3.6, CC: 5.9±2.3 ms/mm Hg; BRSf - AA: 12.0±4.0, AC: 12.0±5.0, CC: 8.0±3.0 mHz/mm Hg). Compared to carriers of other genotypes (AA+AC) the homozygotes with the less frequent allele (CC) showed significantly lower BRSf (Mann-Whitney: BRSf - AA+AC: 12.0±4.0, CC: 8.0±3.0 mHz/mm Hg; p<0.01) and borderline lower BRS (BRS - AA+AC: 8.2±3.5, CC: 5.9±2.5 ms/mm Hg; p=0.07). We found a significant association of A1166C polymorphism in AT1 receptor gene with baroreflex sensitivity. Homozygosity for the less frequent allele was associated with decreased baroreflex sensitivity., M. Jíra ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Both, common gene variants and human adenovirus 36 (Adv36) are involved in the pathogenesis of obesity. The potential relationship between these two pathogenic factors has not yet been investigated. The aim of our study was to examine the association of obesity susceptibility loci with Adv36 status. Genotyping of ten gene variants (in/near TMEM18, SH2B1, KCTD15, PCSK1, BDNF, SEC16B, MC4R, FTO) and analysis of Adv36 antibodies was performed in 1,027 Czech adolescents aged 13.0-17.9 years. Variants of two genes (PCSK1 and BDNF) were associated with Adv36 seropositivity. A higher prevalence of Adv36 antibody positivity was observed in obesity risk allele carriers of PCSK1 rs6232, rs6235 and BDNF rs4923461 vs. noncarriers (χ2=6.59, p=0.010; χ2=7.56, p=0.023 and χ2=6.84, p=0.033, respectively). The increased risk of Adv36 positivity was also found in PCSK1 variants: rs6232 (OR=1.67, 95 % CI 1.11-2.49, p=0.016) and rs6235 (OR=1.34, 95 % CI 1.08-1.67, p=0.010). PCSK1 rs6232 and BDNF rs925946 variants were closely associated with Adv36 status in boys and girls, respectively (χ2=5.09, p=0.024; χ2=7.29, p=0.026). Furthermore, PCSK1 rs6235 risk allele was related to Adv36 seropositivity (χ2=6.85, p=0.033) in overweight/obese subgroup. In conclusion, our results suggest that obesity risk variants of PCSK1 and BDNF genes may be related to Adv36 infection., L. Dušátková, H. Zamrazilová, I. Aldhoon Hainerová, R. L. Atkinson, B. Sedláčková, Z. P. Lee, J. Včelák, B. Bendlová, M. Kunešová, V. Hainer., and Obsahuje bibliografii
Present study aimed to explore the levels and correlation of oxidative stress biomarkers with anthropometry in a population of young Saudi females. One hundred six normotensives, non-diabetic Saudi females, with minimally active lifestyle, based on their body mass index (BMI) were divided as; normal-weight (NW; n=52), overweight (OW; n=24) and obese (OB; n=30). Anthropometric measurements [BMI, Waist Circumference (WC), Waist-Hip Ratio (WHR), Body Density (BD), Body Adiposity Index (BAI), % Body fat] and oxidative stress biomarkers; Thiobarbituric acid reactive substances (TBARS), 8-hydroxy-2- deoxyguanosine (8-OH-2dG: indicative of DNA/RNA damage), Superoxide dismutase, Serum total antioxidant capacity) were recorded. There was statistically significant higher 8-OH-2dG (pg/ml) in OB compared to NW (800.63±6.19 vs. 780.22±3.34; p=0.007), as determined by one-way ANOVA and Tukey post hoc test. 8-OH-2dG was significantly and positively associated with BMI (r=0.286, p=0.004), WC (r=0.280, p=0.005), BAI (r=0.26, p=0.008), and % body fat (r=0.27, p=0.006). There may be significantly increased DNA damage in normoglycemic, normotensive obese adolescent females. This can be linked to the amount of adipose tissue in the body as depicted by strong positive association between DNA damage and BMI, WC, BAI, and % body fat., R. Latif, N. Rafique., and Obsahuje bibliografii
The LRP5 gene is believed to be primarily associated with bone metabolism via Wnt signaling. The latter pathway, however, appears to control various other systems outside the skeleton. To find the relationships of the LRP5 gene to serum follicle stimulating hormone (FSH ) and luteinizing hormone (LH) in the cohort of normal postmenopausal women, we identified the C/T (c.4037:A1330V) polymorphism in the LRP5 gene using a restriction analysis of the PCR product in a cohort of 165 untreated pre- and post-menopausal women. In a subset of 111 post-menopausal women we analyzed the association between the LRP5 genotype and serum levels of sex-hormones including FSH and LH. The distribution of CC, TC and TT genotypes of the C/T polymorphism in the whole group was 73.9 %, 23.6 % and 2.4 %, respectively, which is comparable with other Caucasian populations. As no TT homozygote was found in the group of post-menopausal women, serum sex-hormones were compared between CC and TC genotypes. Women with the CT allele combination had markedly higher serum FSH levels as compared to carriers of the CC genotype (p<0.004). No differences between these genotypes were found in serum LH levels as well as the circulating sex-steroids such as estradiol, testosterone, dehydroepiandrosterone and/or its sulphate, androstenedione and SHBG. To conclude, the LRP5 gene is associated with circulating FSH in normal post-menopausal women in the present study. The mediating role of subtle undetectable variations in estrogen levels is discussed. We did not find any relationship between the LRP-5 genotype and serum LH levels., I. Žofková, M. Hill, K. Zajíčková., and Obsahuje bibliografii a bibliografické odkazy