Search results for "Star"
showing 10 items of 4285 documents
La Europa de los Estados
2003
Density-dependent winter survival of immatures in an irruptive raptor with pulsed breeding
2021
Highly mobile predators can show strong numerical responses to pulsed resources, sometimes resulting in irruptions where large numbers of young invade landscapes at a continental scale. High production of young in irruption years may have a strong influence on the population dynamics unless immature survival is reduced compared to non-irruption years. This could occur if subordinate individuals (mainly immatures) are forced into suboptimal habitats due to density-dependent effects in irruption years. To test whether irruptive individuals had lower survival than non-irruptive ones, we combined necropsy results (N = 365) with telemetry (N = 185) from more than 20 years to record timing and ca…
Dual inhibition of cyclooxygenase-1 and 5-lipoxygenase by aerial part of Bupleurum fruticescens methanol extract
2003
The effect of the methanol extract from aerial parts of Bupleurum fruticescens on the release of eicosanoids and hydrolytic enzymes was determined on in vitro cell systems. The extract had a significant effect on 5-lipoxygenase (5-LOX) activity, inhibiting both LTB4 and 5(S)-HETE production with IC50 values of 112 microg/ml and 95 microg/ml, respectively. At concentrations of 200 microg/ml, the extract also inhibited cyclooxygenase-1 (90%) and elastase activities (54%). The 12-LOX activity in intact platelets was not affected; a fact, which suggests that phospholipase A2 (PLA2) activity, is not modified by the extract.
Search for Gravitational-wave Signals Associated with Gamma-Ray Bursts during the Second Observing Run of Advanced LIGO and Advanced Virgo
2019
We present the results of targeted searches for gravitational-wave transients associated with gamma-ray bursts during the second observing run of Advanced LIGO and Advanced Virgo, which took place from 2016 November to 2017 August. We have analyzed 98 gamma-ray bursts using an unmodeled search method that searches for generic transient gravitational waves and 42 with a modeled search method that targets compact-binary mergers as progenitors of short gamma-ray bursts. Both methods clearly detect the previously reported binary merger signal GW170817, with p-values of <9.38 10-6 (modeled) and 3.1 10-4 (unmodeled). We do not find any significant evidence for gravitational-wave signals associate…
Enterprise Start-Up in the Euro-Mediterranean Area. The case-study of Mazara Del Vallo’s Fishing District and Consortium
2016
Over the last twenty years, the European Union’s policies aiming to foster the entrepreneurship in the Euro-Mediterranean countries have failed. The theoretical model underlying these policies is inconsistent with the characteristics of the entrepreneurial ecosystems of these countries.Since no enterprise can survive in the long run if it has inconsistent characters with the ecosystem in which it operates, in Euro-Mediterranean countries it is necessary to adopt a specific theoretical model on start-up business, different from the one described by the international literature. The fundamental principles of this theoretical model therefore must be drawn from the common characteristics of suc…
New evidence on accelerator performance based on funding and location
2020
Seed accelerators (SAs) appear as a more advanced version of business incubators. These for-profit organizations in exchange of equity, help setting new start-ups by providing mentoring and funding during its first months. Due to their emergent nature, the impact and expectations of SAs remains largely unknown. Therefore, the purpose of this study is to throw new light on this field by empirically assessing for the first time the performance and prospects of these organizations through a survey of 116 SAs.,A model based on the Business Incubators literature is built with four categories covering size, location, age and profitability variables, leading to two hypotheses to be tested empirica…
Bēgļu izraidīšanas vai atgriešanas aizlieguma eksteritoriālais raksturs atklātajā jūrā kā starptautiskā paražu tiesību norma
2019
Darbā tiek aplūkota bēgļu izraidīšanas vai atgriešanas aizlieguma teritoriālā piemērojamība, izvērtējot tā darbību ārpus valstu robežām atklātajā jūrā. Saistībā ar bēgļu ierašanās pa jūru izpausmi mūdienās, īpaši nozīmīga ir bēgļu izraidīšanas vai atgriešanas aizlieguma attiecināmība uz masveida pieplūduma situācijām. Vienlaikus būtiski ir arī aplūkot vajāšanas satura paplašināšanos mūsdienās, izvērtējot gan tiesu praksi, gan tā mijiedarbību ar cilvēktiesībām. Tālāk tiek izvērtēta trešās drošās valsts koncepta nozīme bēgļu izraidīšanas vai atgriešanas piemērošanas robežu noteikšanā. Savukārt darba beigās autore analizē bēgļu izraidīšanas vai atgriešanas eksteritoriālo piemērojamību atklātaj…
Saskarsmes un sadarbības prasmju veicināšanas pedagoģiskās iespējas 5-6 gadu veciem bērniem pirmsskolā
2017
Bakalaura darba temats ir “Saskarsmes un sadarbības prasmju veicināšanas pedagoģiskās iespējas 5-6 gadu veciem bērniem pirmsskolā”. Pētījuma problēma: pētījumā tiek veikta pedagoģisko un psiholoģisko metožu un tehniku izpēte, kuras var pielietot bērnu savstarpējās sadarbības veicināšanai pedagoģiskajā procesā. Teorētiskais pamats: pētījums tiek balstīts uz pieņēmumu, ka bērnu saskarsmes problēmas var tikt atrisinātas ar skološanas un mācību, rotaļu palīdzību. Darba mērķis ir analizēt 5-6 gadu vecu bērnu saskarsmes un sadarbības prasmju pedagoģiskās iespējas latviešu valodas apguvē. Pētījuma objekts: pedagoģiskais process pirmsskolā Pētījuma priekšmets: Sadarbības prasmju veicināšanas iespēj…
Ogļskābes anhidrāzes XII izoformas strukturālie pētījumi
2017
Ogļskābes anhidrāzes katalizē dzīvajos organismos būtisko bikarbonāta un ogļskābās gāzes savstarpējo atgriezenisko reakciju. Cilvēka organismā ir vairākas ogļskābes anhidrāžu izoformas, un dažu izoformu katalītiskā darbība ir nevēlama. Viena no šīm izoformām, ogļskābes anhidrāzes XII izoforma, saistīta ar vairāku ļaundabīgu audzēju attīstību. Maģistra darba iztrādē tika vairākkārtīgi uzlabota ogļskābes anhidrāzes XII izoformas ekspresijas un attīrīšanas sistēma un iegūtas vairākas ar ligandu saistītas ogļskābes anhidrāzes XII izoformas struktūras. Ar proteīnu rentgenstaru kristalogrāfijas palīdzību tika identificētas dažādu inhibitoru konformācijas ogļskābes anhidrāzes XII izoformas aktīvaj…
MILES extended: Stellar population synthesis models from the optical to the infrared
2016
We present the first single-burst stellar population models which covers the optical and the infrared wavelength range between 3500 and 50000 Angstrom and which are exclusively based on empirical stellar spectra. To obtain these joint models, we combined the extended MILES models in the optical with our new infrared models that are based on the IRTF (Infrared Telescope Facility) library. The latter are available only for a limited range in terms of both age and metallicity. Our combined single-burst stellar population models were calculated for ages larger than 1 Gyr, for metallicities between [Fe/H] = -0.40 and 0.26, for initial mass functions of various types and slopes, and on the basis …