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Estudios sobre Rubiáceas Mexicanas XLIV : Una nueva especie del género Guettarda (Rubiaceae, Guettardeae) en el Estado Guerrero
No full textA new species of Guettarda is described from a collection made by José C. Soto Nuñez in Guerrero. It is similar to G. guerrerensis Borhidi of Guerrero and G. quadrifida Borhidi et Reyes-García of Chiapas, and grows in tropical deciduous forests on igneous rocks
Vegetation analysis of six riverian islands in hyper-arid environments at Qena Governorate (Upper Egypt)
No full textThe present study aims at analysing the vegetation of six riverian islands at Qena Governorate, Upper Egypt. 160 taxa of angiosperms and one pteridophyte species were recorded in six sedimentary islands located throughout the Nile stream at Qena Governorate, Upper Egypt. Of these, Hibiscus diversifolius (Malvaceae) recorded as a new record to the flora of Egypt. Therophytes represent 51.6% of the life form spectrum. Pantropical, Palaeotropical and Cosmopolitan elements (31.1%, 18.6% and 21.7%, respectively) were the dominant floristical categories among the total number of species. Vegetation analysis using TWINSPAN technique classified the 103 stands surveyed in the studied islands into ten vegetation clusters were obtained and categorised into 4 distinct groups according to soil moisture and chemical characteristics (TDS, EC, sodium and phosphate concentrations) appeared to be important attributes in characterising the vegetation clusters
A new Aceria species (Acari: Prostigmata: Eriophyoidea) on Xeranthemum annuum from Hungary
No full textFemale, male and nymph of Aceria bajani n. sp., associated with Xeranthemum annuum, are described from Hungary. Taxonomically relevant morphological details are illustrated and the species is diagnosed from other asteraceous inhabiting congeners
Investigation of delta-aminolevulinic acid dehydratase polymorphism affecting hematopoietic, hepatic and renal toxicity from lead in Han subjects of southwestern China
No full textThis study is to explore the effect of ALAD polymorphism on hematopoietic, hepatic and renal toxicity from lead in occupational exposure worker
Physiological response is similar in overweight and normoweight boys during cycling: A longitudinal study
No full textThe purpose of this study was to determine whether metabolic cost is similar in overweight and normoweight children when workload during exercise on a cycle-ergometer is adjusted relative to an objectively determined second ventilatory threshold (VT2) or the maximal workload (Pmax). The tests were conducted every 2 years: first at the age of 10 years and the third test at around the age of 14 years. The levels of maximal oxygen consumption (VO2max), Pmax, and the VT2 were determined by means of graded tests on a cycle ergometer. The main test consisted of two 6-minute exercises of submaximal constant intensity (below and above VT2) performed on a cycle ergometer, with a 4-minute recovery between efforts. The workload during cycling was adjusted individually for each participant and adjusted to the values determined in the graded test: workload at VT2 and Pmax. Physiological response (absolute and relative to free-fat mass oxygen uptake, heart rate, pulmonary ventilation, tidal volume, and breathing frequency) is similar in overweight and normoweight boys when workload on a cycle ergometer is adjusted to VT2. The only significant intergroup difference was seen in relative to body mass oxygen intake
Effects of hypoxia and hypercapnia on human HRV and respiratory sinus arrhythmia
No full textPurpose:
Hypercapnia increases minute ventilation (V’E) with little effect on heart rate (HR), whereas hypoxia may
increase HR without affecting V’E. However, the effects of hypercapnia and hypoxia on both heart rate variability
(HRV) and the clustering of heart beats during spontaneous breathing (respiratory sinus arrhythmia – RSA), are not
clear.
Methods:
In this study, 10 human volunteers breathed room air (RA), hypercapnic (5% CO
2
) or hypoxic (10%
O
2
) gas mixtures, each for 6 min, while resting supine. ECG, mean arterial pressure (MAP), ventilatory flow, inhaled
and exhaled fractions of CO
2
and O
2
, were recorded throughout.
Results:
Both V’E and MAP increased with 5%
CO
2
, with no change in HR. Hypoxia did not change ventilation but increased HR. High frequency components of
HRV, and the relative proportion of heart beats occurring during inhalation increased with 5% CO
2
, but neither
changed with 10% O
2
.
Conclusion:
Increased RSA concomitant with increased MAP suggests RSA – vagal
dissociation with hypercapnia. Elevated heart rate with acute hypoxia with no change in either frequency components
of HRV or the distribution of heart beats during ventilation, suggested that clustering of heart beats may not be a
mechanism to improve ventilation-perfusion matching during hypoxia.
Keywords:
autonomic nervous system, spectral analysis, cardiovascular control, heart rate variability, hypoxia,
hypercapni
Ten-year cardiovascular risk assessment in university students
No full textCardiovascular disease (CVD) is responsible for more than half of all deaths in the European region. The aim of the study was to compare body composition, blood pressure, total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C), family history, activity behaviors, and the 10-year risk of having a heart attack between 166 university students (21.62 ± 2.59 yrs) from Utah (USA) and 198 students (22.11 ± 2.51 yrs) from Hungary. Ninety-two percent of the Hungarian students and 100% of the Utah students had an estimated 10-year Framingham risk score of 1% or less. The high prevalence of low risk was primarily due to the young age of study participants, healthy body composition and non-smoking behavior. Hungarians who had higher 10-year risk of heart attack had significantly higher waist hip ratio (WHR), TC, diastolic blood pressure (DBP) and were smokers compared to those Hungarians with lower risk. The self-reported physical activity levels between the two groups of students were not different. In conclusion the young men and women who participated in this study were, for the most part healthy; however the smoking habits and the lower physical activity of the Hungarian students likely elevated their risk of CVD
Effect of some Physiological Properties on the Quality Parameters of Different Winter Wheat Varieties in a Long-term Experiment
No full textWe have investigated the relationship between the quality parameters, the chlorophyll content and the leaf area index of three different winter wheat genotypes in two different crop years on chernozem soil. The correlations between the qualitative traits and physiological parameters were medium or tight in several cases. The obtained data suggest that the chlorophyll content, the size of the leaf area and the decrease of the assimilation capacity during the generative phase influence the qualitative parameters. Among the qualitative values the valorigraphic value performed lesser correlation between the studied physiological traits. The wet gluten content and the protein content of the flour showed very tight correlation with the chlorophyll content and the leaf area index. The correlations between the studied parameters were the strongest during flowering in the majority of the cases, thus their analysis during these phenophases results in better predictability. These results show that the extent of the assimilation capacity — which significantly influences the nutritional value of the grain during maturation — can be determined by analyzing all the data measured during the different phenophases
TaWRKY71, a WRKY Transcription Factor from Wheat, Enhances Tolerance to Abiotic Stress in Transgenic Arabidopsis thaliana
No full textMembers of WRKY gene family encode transcription factors involved in plant developmental processes and response to biotic and abiotic stresses. In order to understand the function of the TaWRKY71 gene, a homologue gene was isolated and characterised in wheat (Triticum aestivum L.) genotype TAM107. Tissue-specific gene expression profiles indicated that TaWRKY71 was constitutively expressed in roots, stems, leaves, stamen and pistil. The relative expression of TaWRKY71 was elucidated under ABA treatment and other abiotic stresses. In agreement with this, several putative cis-acting elements involved in ABA-response, drought-inducibility, low-temperature and heat response were detected in the promoter region of TaWRKY71. The function of TaWRKY71 was further determined by transforming Arabidopsis thaliana. Transgenic plants over-expressing TaWRKY71 displayed enhanced seed germination under ABA treatment and were tolerant to salt and drought stresses. These results indicate that TaWRKY71 gene might play important roles in seed germination and abiotic stress response
Hybrid performance and inbred-hybrid relationship of early maturing tropical maize under drought and well-watered conditions
No full textDrought tolerant maize (Zea mays L.) hybrids are crucial to sustainability of maize production in West and Central Africa (WCA). Two studies were conducted at three locations in Nigeria for 2 yr to (i) assess performance of 156 early-maturing maize inbreds and three hybrid types and (ii) determine heterosis among the lines and relationship between lines per se and hybrid performance. The inbreds and their hybrids were evaluated separately under drought and well-watered conditions. Genotype, environment and genotype × environment interactions were significant for grain yield under the research conditions. Grain yield of inbreds ranged from 0.06 t ha−1 for TZEI 123 to 1.92 t ha−1 for TZEI 17 under drought. While differences in grain yield among hybrid types (single, three-way and double-cross hybrids) were not significant under drought, significant differences were detected among hybrid types under optimal conditions. GGE biplot analysis identified three inbreds, TZEI 18, TZEI 56, and TZEI 1 and hybrids TZEI 129 × TZEI 16, (TZEI 17 × TZEI 16) × TZEI 157 and (TZEI 16 × TZEI 157) × TZEI 129 as ideal across research conditions. Midparent heterosis (MPH) and high-parent heterosis (HPH) for grain yield were higher in the well-watered conditions than under drought. Positive and significant correlations existed between MPH, HPH and yield under both research conditions. Drought tolerant hybrids with stable and high yield are available for promotion for adoption by farmers in WCA