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1232. Masai Mara. I. Jedna z legend africké přírody
- Creator:
- Miloš Anděra
- Format:
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, savci, národní parky, ekologie, mammals, national parks, ecology, Afrika, Africa, 2, and 59
- Language:
- Czech
- Description:
- Keňská národní rezervace Masai Mara (též Maasai Mara) o rozloze 1 510 km2 se nachází ve Velké příkopové propadlině a přímo navazuje na národní park Serengeti v severní Tanzanii. Většinu jejího území pokrývají mírně zvlněné travnaté savany živené četnými srážkami v několika obdobích dešťů od listopadu do dubna. Pouze území v blízkém okolí řeky Mary a jejích přítoků jsou zalesněná. Rezervace je celosvětově proslulá mimořádně početnými migrujícími stády velkých kopytníků a jejich predátorů. V posledních desetiletích však populace některých druhů výrazně ubývají, za hlavní rizikové faktory se považuje rozšiřující se pastva skotu a nekontrolovaný rozvoj cestovního ruchu., Kenya’s Masai Mara National Reserve, covering an area of 1,510 km2, is situated in the Rift Valley with Tanzania’s Serengeti Plains running along its southern end. Most of the reserve is made up of hilly grassland, fed by plentiful rain, especially during the wet months between November and April. Only the areas near the Mara river and its tributaries are forested. The reserve is famous for its exceptional migrating populations of larger ungulates and its predators. However, the last decades have seen a considerable decrease in abundance of some species - the main causes are expanding livestock grazing and uncontrolled development of tourism., and Miloš Anděra.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1233. Masai Mara. II. Dvojí velké stěhování
- Creator:
- Miloš Anděra
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, savci, národní parky, zoology, mammals, national parks, Keňa, Kenya, Národní park Serengeti (Tanzanie), Serengeti National Park (Tanzania), 2, and 59
- Language:
- Czech
- Description:
- Rezervaci Masai Mara proslavila především každoroční masová migrace pakoňů žíhaných (Connochaetes taurinus) a dalších kopytníků ze Serengeti (Tanzanie). Primární příčinou stěhování je střídání srážkového cyklu v rovníkové východní Africe a s tím související nabídka zelené potravy. Je ovšem obtížné určit přesný začátek či konec velkého stěhování – jde o neustále běžící cyklus, jehož jednotlivé fáze přecházejí plynule jedna v druhou. Navíc načasování migrací se rok od roku liší podle počasí i v řádu měsíců. Celá migrační trasa o délce zhruba 800 km má podobu nepravidelného oválu. Pohyb mnohatisícových až milionových stád přitahuje množství turistů z celého světa (druhé stěhování)., The Masai Mara reservation is famous for its annual mass migration of the Wildebeest (Connochaetes taurinus) and other hoofed animals from the Serengeti (Tanzania). Its primary cause is the changing precipitation cycle in equatorial east Africa, and the related supply of green food. It is difficult to determine exactly the beginning and the end of the Great Migration – it is a constantly running cycle, and its timing varies from year to year depending on weather conditions over a span of months. The entire route has a length of about 800 km. The movement of herds with hundreds of thousands to millions of animals attracts an ever-increasing number of tourists from around the world annually (the second migration)., and Miloš Anděra.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1234. Masožravá rostlina láčkovka Nepenthes ampullaria využívá listový odpad
- Creator:
- Lubomír Adamec
- Format:
- Type:
- article, zprávy, model:article, and TEXT
- Subject:
- Botanika, masožravé rostliny, 2, and 58
- Language:
- Czech
- Description:
- Lubomír Adamec.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1235. Mass spectrometry analyses of rat 2b myosin heavy chain isoform
- Creator:
- Jitka Žurmanová, Daniela Horníková, František Půta, Petr Novák, Jan Říčný, and Tomáš Soukup
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Obecná zoologie, fyziologie živočichů, mikrobiologie, spektrometrie, animal physiology, microbiology, spectrometry, rat muscle myosin, myosin heavy chain 2b isoform, MALDI TOF mass spectrometry, ESI LC/MS/MS mass spectrometry, 2, and 591
- Language:
- English
- Description:
- We have separated 2b myosin heavy chain (MyHC) isoform from the rat extensor digitorum longus muscle by SDS-PAGE and analyzed it by two subsequent mass spectrometry techniques. After tryptic digestion, the obtained peptides were identified by Matrix-Assisted Laser Desorption/Ionisation reflectron Time of Flight mass spectrometry (MALDI-TOF MS) and sequenced by Liquid chromatography tandem mass spectrometry (ESI LC/MS/MS). The analyzed peptides proportionally covered 30 % of the 2b MyHC isoform sequence. The results suggest that the primary structure is identical with the highest probability to a NCBI database record ref|NP_062198.1|, representing the last updated record of rat 2b isoform. Nonetheless, four peptides carrying amino acid substitution(s) in comparison with the NCBI database record were identified., J. Žurmanová, D. Maláčová, F. Půta, P. Novák, J. Říčný, T. Soukup., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1236. Mating advantage of short-winged over long-winged adult males in the cricket Velarifictorus ornatus (Orthoptera: Gryllidae)
- Creator:
- Zhao, Lv-Quan, Chai, Huai-Lin, Wu, Hong-Jun, and Zhu, Dao-Hong
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, rovnokřídlí, cvrčkovití, Orthoptera, Gryllidae, Velarifictorus ornatus, mating competition, sing song, trade-off, wing polymorphism, 2, and 59
- Language:
- English
- Description:
- The trade-off between flight capability and reproduction is well known in adult males of insects with wing dimorphism but the reproductive advantage of short-winged (SW) males over long-winged (LW) males appears to vary across insect taxa. In the present study, we determined the difference in the mating ability of SW and LW males of Velarifictorus ornatus (Orthoptera: Gryllidae) in order to evaluate whether the SW male morph has a reproductive advantage. We found that the choice of a mate depended on the female. Compared with LW males, SW males had an obvious mating advantage when both SW and LW males courted females simultaneously, and that dealation significantly enhanced the mating ability of LW males. Losing the ability to produce songs reduced the mating advantage of SW males, thereby indicating that the greater mating advantage of SW males was related to the attractiveness of the song. In addition, the difference in the mating ability of LW and SW males was not related to body size or age. These results indicate that SW males of V. ornatus have a mating advantage over their LW counterparts because their underdeveloped flight muscles allow them to devote more resources to reproduction., Lv-Quan Zhao, Huai-Lin Chai, Hong-Jun Wu, Dao-Hong ZhuU., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1237. Mating alters the rate of development of ovarioles in the ladybird, Propylea dissecta (Coleoptera: Coccinellidae)
- Creator:
- Shahid, Mhd, Siddiqui, Arshi, Omkar, and Mishra, Geetanjali
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, věk, beetles, Coccinellidae, age, Coleoptera, Propylea dissecta, mating status, ovariole development, egg maturation, egg load, 2, and 59
- Language:
- English
- Description:
- The influence of female mating status on ovarian development of the ladybird, Propylea dissecta (Mulsant) (Coleoptera: Coccinellidae), was investigated under laboratory conditions. We assessed the extent to which ovariole development was affected by mating and for that we initially created a base line by observing age specific ovariole development. Results show that the number of follicles in each ovariole increased with the age of both virgin and mated females up to the age of 3 days, thereafter, no increase in number of follicles was recorded. Ovariole width also increased with age in both virgin and mated females up to 4 days, thereafter, no increase in ovariole width was recorded. The ovariole width of mated females was significantly greater than that of virgin females. Egg maturation and the egg load started to increase at the age of 8 days in virgin females. Thereafter, it increased with increase in female age. While in mated females, immature eggs were recorded in their ovarioles from the age of 1 to 2 days. In mated females, however, the increase in the number of mature eggs per ovariole and egg load started when they were 3 days old. Egg load continuously increased with increasing female age., Mhd Shahid, Arshi Siddiqui, Omkar, Geetanjali Mishra., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1238. Measurements of reflectance and fluorescence spectra for nondestructive characterizing ripeness of grapevine berries
- Creator:
- Navrátil, M. and Buschmann, C.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, Cabernet Sauvignon, CIE 1931, plant pigments, Riesling, 2, and 581
- Language:
- Multiple languages
- Description:
- In vivo reflectance and fluorescence spectra from berry skins of a white (Riesling) and red (Cabernet Sauvignon) grapevine variety were measured during a ripening season with a new CMOS radiometer instrument. Classical reference measurements were also carried out for a sugar content of the berry juice [°Brix] and pigment contents (chlorophyll a and b, carotenoids, anthocyanins) from methanol extracts of the berry skin. We showed that the colours and the spectra analysed from them could be taken as an unambiguous indicator of grapevine ripening. Reflectance spectra, which were affected by the content of pigments (chlorophylls and anthocyanins), effects of surface (wax layers), and tissue structure (cell size) of the berries well correlated (R2 = 0.89) with the °Brix measurements of the berries. The fast data acquisition of both reflectance and fluorescence spectra in one sample with our radiometer instrument made it superior over the time-consuming, traditional, and mostly destructive chemical analysis used in vine-growing management., M. Navrátil, C. Buschmann., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1239. Mechanismy vývinu hypertenze závislé na soli
- Creator:
- Michal Pravenec
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biologické vědy, hypertenze, kuchyňská sůl, hemodynamika, fyziologie, hypertension, table salt, hemodynamics, physiology, vliv soli, mineralokortikoidy, aldosteron, mineralocorticoids, 2, and 57/59
- Language:
- Czech
- Description:
- Hypertenze závislá na soli patří mezi nejčastější rizikové faktory kardiovaskulárních onemocnění. U většiny případů je příčina tohoto onemocnění neznámá, avšak významný podíl hypertenzních jedinců citlivých k soli má zvýšené hladiny mineralokortikoidů. V tomto přehledném článku popisujeme hemodynamické abnormality a mechanismy odpovědné za vývin této formy hypertenze., Salt-dependent hypertension is a leading cause of cardiovascular diseases. In most cases, the etiology is unknown, but it has been estimated that a significant percentage of salt-sensitive hypertensive individuals have mineralocorticoid excess. In this review, we describe hemodynamic abnormalities and mechanisms responsible for initiation of this form of hypertension., and Michal Pravenec.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1240. Mechorosty České republiky
- Creator:
- Jan Kučera
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Botanika, flóra, mechy, mechorosty, Česko, 2, and 58
- Language:
- Czech
- Description:
- Bryophytes, with their more than 860 species, represent more than a quarter of higher plants native to the CR. They can reveal much more about the ecosystems they live in than we would expect, as their physiological contact with the surroundings is much closer than that of the vascular plants. and Jan Kučera.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public