Search results for "Master"
showing 10 items of 340 documents
Augsnes granulometrija un to frakciju raksturošana
2020
Darbā ir veikta augsnes granulometriska pārbaude izmantojot sedimentācijas metodi un lāzerdifrakcijas metodi izmantojot daļiņu lieluma analizatoru Mastersizer 3000. Visi iegūtie dati tiek analizēti, salīdzinot izmantotas metodes savā starpā. Visiem zemes frakcijām iegūtiem ar lāzerdifrakcijas metodi tika izvērtēti to drošības intervāli un iespējami datu novirzes cēloni no sedimentācijas metodes.
Design, synthesis and stimuli responsive gelation of novel stigmasterol-amino acid conjugates.
2020
Abstract An efficient synthesis of three novel stigmasterol-amino acid (glycine, l -leucine and l -phenylalanine) conjugates as stimuli responsive gelators is reported. The gelation properties of the prepared compounds were investigated in a variety of organic as well as aqueous solvents. The most striking finding of our investigation was that the hydrochloride salts of the prepared conjugates acted as gelators, whereas the neutral conjugates were either non-gelators or formed only a weak gel in anisole. The hydrochloride salts of stigmasteryl glycinate and l -leucinate form gels in n-alcohols (n = 4–10) and in ethane-1,2-diol, and that of stigmasteryl l -phenylalaninate forms gels in aroma…
Two new sesquiterpene derivatives from the Tunisian endemic Ferula tunetana Pom.
2010
A new sesquiterpene ester, tunetanin A (1), a new sesquiterpene coumarin, tunetacoumarin A (2), together with eight known compounds, i.e., coladin (3), coladonin (4), isosmarcandin (5), 13-hydroxyfeselol (6), umbelliprenin (7) propiophenone (8), beta-sitosterol (9), and stigmasterol (10), were isolated from the roots of Ferula tunetana. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D- and 2D-NMR experiments and MS analysis, as well as by comparison with published data. The cytotoxicity of compounds 1-7 towards two human colon cancer cell lines, HT-29 and HCT 116, was evaluated. Compounds 3, 4, and 6 showed weak cytotoxic activities.
Unprecedented new nonadecylpara-hydroperoxycinnamate isolated fromErythrina excelsaand its cytotoxic activity
2014
A new unprecedented cinnamate derivative (1) was obtained from Erythrina excelsa (Leguminosae) and identified as nonadecyl para-hydroperoxycinnamate. This compound was isolated together with three known compounds, namely lupeol (2), mixture of sitosterol and stigmasterol (3), and isoneorautenol (4). Their structures were established on the basis of NMR and mass spectroscopic data in conjunction with those reported in the literature. Compound 1 was evaluated for its capability of inhibiting cancer cell lines and growth of a panel of microbial strains. It turned out that 1 is moderately to significantly cytotoxic against six cancer cell lines and shows weak to no antimicrobial activity.
Relationship between inflammatory biomarkers and testosterone levels in male master athletes and non-athletes.
2021
Background Aging is often associated with low-grade systemic inflammation and reduced anabolic hormone levels. To investigate whether lifelong exercise training can decrease the age-related low-grade inflammation and anabolic hormone levels, we examined hormonal and inflammatory parameters among highly-trained male masters athletes and age-matched non-athletes. Methods From 70 elite power and endurance master athletes – EMA (51.3 ± 8.0 yr), 32 young controls - YC (23.7 ± 3.9 yr) and 24 untrained age-matched controls - MAC (47.2 ± 8.0 yr) venous blood was drawn to measure inflammatory parameters (interleukin-6 [IL-6], tumor necrosis factor-α [TNF-α] and interleukin-10 [IL-10]) and circulatin…
''Limits in endurance performance of octogenarian athletes''
2013
TO THE EDITOR: A recent study of Trappe et al. (3) showed that the aerobic power of octogenarian lifelong endurance athletes was approximately double that of untrained octogenarians (38 vs. 21 ml·kg 1 ·min 1 ). These remarkable aerobic capacities are the highest ever recorded in this age group. However, the impact of the identified physiological capacities on actual endurance performances has not been addressed, as no running performance indicators of the octogenarian athletes were provided in this study. We hereby suggest that, although trained octogenarian athletes can achieve levels of aerobic fitness well above their untrained counterpart, as a group they actually have not yet reached t…
Research in China
2009
My stay in China began in November 1985 with a lecture at the opening of the Max Planck Guest Laboratory in the Institute of Cell Biology at the Chinese Academy of Sciences (CAS) in Shanghai (Hennig, 2000). It marked the beginning of 23 years of research and teaching at the Institute of Cell Biology and other universities throughout China. > Looking back after 23 years, the changes that have taken place in China could not have been predicted in 1985… In January 2001, I accepted a long‐term lectureship offered by the German Academic Exchange Service (DAAD; Bonn, Germany), which, with further support from CAS, allowed me to create my own research group within the Shanghai Institutes for Biolo…
The Mediating Role of Psychological Distress in Excessive Gambling among Young People: A Four-Country Study
2021
Background and aims: Loneliness and a low sense of mastery are associated with excessive gambling, but the underlying processes of these relationships remain unstudied. Because psychological distress can increase vulnerability to excessive gambling, we investigated its mediating role in these relationships among young people. To meet the need for cross-country research, we also observed how these relationships occur in four countries with different cultures. Design, setting, and participants: Demographically balanced cross-sectional survey data were collected from 15–25-year-olds in Finland (n = 1200
The choice of master international franchising – A modified transaction cost model
2022
Abstract This study develops and tests a novel transaction cost model of master international franchising. Based on data from international franchise firms headquartered in six countries, we show that master international franchising is the franchisor’s preferred governance mode under the following conditions: large bilateral franchisor’s and franchisees’ transaction-specific investments, high institutional uncertainty and high behavioral uncertainty. Our model extends the literature by presenting a modified transaction cost model of master international franchising that investigates the bonding effect of bilateral transaction-specific investments and environmental uncertainty as determinan…
Impact of age, performance and athletic event on injury rates in master athletics - First results from an ongoing prospective study
2014
Objectives: Recent studies have identified rates of injuries in young elite athletes during major athletic events. However, no such data exist on master athletes. The aim of this study was to assess incidence and types of injuries during the 2012 European Veteran Athletics Championships as a function of age, performance and athletic discipline. Methods: Report forms were used to identify injured athletes and injury types. Analysis included age (grouped in five-year bands beginning at age 35 years), athletic event, and age-graded performance. Results: Of the 3154 athletes (53.2 years (SD 12.3)) that participated in the championships (1004 (31.8%) women, 2150 (68.2%) men), 76 were registered …