Search results for "LOD"
showing 10 items of 4833 documents
The Odonatoptera of the Late Permian Lodève Basin (Insecta).
2008
8 pages; International audience; The discovery of numerous and very diverse Odonatoptera in the Red Late Permian Lodève Basin questions its current reconstructions of a dry to very dry palaeoclimate and palaeoenvironment. It rather suggests the presence of more or less permanent water bodies, surrounded by a diversity of terrestrial biotas. The discovery of large to very large Meganeuridae contradicts the alleged relations between the decrease of body and wing sizes of the insects during the late Permian as a direct consequence of the decrease of the oxygen atmospheric concentrations at that time.
Utopiju un antiutopiju iezīmes Luisas Lorijas Romānā “Devējs”
2016
Pašreizējais darbs ir veltīts Luisas Lorijas romāna Devējs analīzei. Pētījuma mērķis ir uzzināt kāda ir literāro utopiju un antiutopiju izcelsme un to attīstība, kādas raksturīgās iezīmes ir atrodamas ievērojamu utopiju un antiutopiju autoru darbos, un, lai atklātu kuras iezīmes Lorijas darbam ir kopīgas ar Tomasa Mora, Tommazo Kampanellas un citu utopiju un antiutopiju autoru darbiem. Pētījumā tiek izmantotas satura analīzes, uzmanīga lasījuma, un interpretācijas metodes. Galvenie rezultāti parāda, ka ideja par utopisku vietu pastāv jau vairākus gadsimtus, un, ka antiutopiskā literatūra parādījās kā atbilde uz cilvēces neveiksmīgajiem mēģinājumiem radīt reālas utopiskas kopienas. Tika izda…
Transmembrane form agrin-induced process formation requires lipid rafts and the activation of Fyn and MAPK.
2009
Overexpression or clustering of the transmembrane form of the extracellular matrix heparan sulfate proteoglycan agrin (TM-agrin) induces the formation of highly dynamic filopodia-like processes on axons and dendrites from central and peripheral nervous system-derived neurons. Here we show that the formation of these processes is paralleled by a partitioning of TM-agrin into lipid rafts, that lipid rafts and transmembrane-agrin colocalize on the processes, that extraction of lipid rafts with methyl-β-cyclodextrin leads to a dose-dependent reduction of process formation, that inhibition of lipid raft synthesis prevents process formation, and that the continuous presence of lipid rafts is requ…
Bias and humidity effects on the ammonia sensing of perylene derivative/lutetium bisphthalocyanine MSDI heterojunctions
2016
International audience; In this paper, we prepared and studied sensors based on Molecular Semiconductor-Doped Insulator (MSDI) heterojunctions. These original devices are built with two stacked layers of molecular materials and exhibit very specific electrical and sensing properties. We studied the properties of a MSDI composed of the perylenetetracarboxylic dianhydride, PTCDA, or the fluorinated perylenebisimine derivative, C4F7-PTCDI, as n-type molecular material sublayers, and LuPc2 as a p-type semiconductor top layer. Their response to ammonia was compared to that of a resistor formed of only the top layer of the MSDI (LuPc2). Ammonia increases the current in the MSDIs whereas it causes…
Muskuļu noslodze transportēšanas cauruļvadu apkalpošanas un remonta dienesta darbiniekiem. Preventīvie pasākumi.
2016
Maģistra darba nosaukums ir „Muskuļu noslodze transportēšanas cauruļvadu apkalpošanas un remonta dienesta darbiniekiem. Preventīvie pasākumi”. Darba autore ir Kristīne Kluša. Darba zinātniskais vadītājs: profesors, Dr.chem. Arturs Vīksna. Darbs ir izklāstīts uz 111 lpp., ietver 93 attēlus, 1 tabulu, 9 pielikumus, izmantoti 62 literatūras avoti. Maģistra darba pētījums sastāv no četrām galvenajām daļām. Pirmajā daļā ir veikts gan latviešu, gan ārzemju literatūras detalizēts apskats un tās kritisks izvertējums atbilstoši iepriekšminētajai maģistra darba tēmai. Otrajā daļā ir aprakstītas pētījumā izmantotās metodes (elektromiogrāfija, kustību analizators un RULA metodika kustību analīzei). Tre…
Mācību vārdnīcas kā skolotāja darba resursi
2016
Bakalaura darbā ar tēmu „Mācību vārdnīca kā skolotāja darba resursi’’, tiek pētītas divas mācību vārdnīcas - Longman Learner’ Dictionary of Contemporary English un Macmillan English Dictionary for Advanced Students. Šī darba mērķis ir pētīt izvēlētās mācību vārdnīcas, kā skolotāja resursus uzdevumu izstrādē četrām valodas prasmēm. Darba procesā izveidojas trīs galvenās nodaļas, un pirmā nodaļa atbild par teorētisko fonu, kurā tiek apkopota informācija par mācīšanas materiāliem, precīzāk, par vārdu krājuma mācīšanas materiāliem un metodēm, tāpat arī tiek analizētas četras valodas prasmes lasīšana, rakstīšana, runāšana un klausīšanās. Šī informācija tiek arī tālāk pielietota praktiskajā daļā.…
Total synthesis of two potent anti-inflammatory macrolactones of the oxacyclododecindione type
2015
An esterification/Friedel-Crafts-cyclization approach permitted the first successful synthetic entry into the oxacyclododecindione subclass of the dihydroxyphenylacetic acid lactone-type natural products. This route allowed the preparation of two highly active anti-inflammatory fungal secondary metabolites 14-deoxyoxacyclododecindione and 14-deoxy-4-dechlorooxacyclododecindione as well as their 14-desmethyl analogues.
On Complex Formation between 5-Fluorouracil and β-Cyclodextrin in Solution and in the Solid State: IR Markers and Detection of Short-Lived Complexes …
2020
In this work, the nuclear magnetic resonance (NMR) and IR spectroscopic markers of the complexation between 5-fluorouracil (5-FU) and &beta
A new depsidone derivative from mangrove sediment derived fungus
2018
A new depsidone derivative botryorhodine I (1), along with eight known compounds (2-9) were obtained from solid rice cultures of the fungal strain, Lasiodiplodia theobromae M4.2-2 isolated from a mangrove sediment sample. The structures of the isolated compounds were elucidated on the basis of 1 D and 2 D NMR analysis as well as by HRESIMS. All compounds were evaluated for their cytotoxic potential against the mouse lymphoma cell line L5178Y as well as for their antibacterial activities against a panel of Gram-positive and Gram-negative bacterial strains. Compound 3 revealed potent cytotoxic activity with an IC50 of 7.3 µM whereas compound 7 showed selective anti-bacterial activity against …
Daphnia females adjust sex allocation in response to current sex ratio and density
2018
Cyclical parthenogenesis presents an interesting challenge for the study of sex allocation, as individuals’ allocation decisions involve both the choice between sexual and asexual reproduction, and the choice between sons and daughters. Male production is therefore expected to depend on ecological and evolutionary drivers of overall investment in sex, and those influencing male reproductive value during sexual periods. We manipulated experimental populations, and made repeated observations of natural populations over their growing season, to disentangle effects of population density and the timing of sex from effects of adult sex ratio on sex allocation in cyclically parthenogenetic Daphnia…