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1832. Aging effects in an evolving phonological network
- Creator:
- Luef, Eva Maria
- Publisher:
- Charles University
- Type:
- text and corpus
- Subject:
- network aging, English as a second language, network evolution, phonological network, and preferential attachment
- Language:
- English
- Description:
- Phonological networks are representations of word forms and their phonological relationships with other words in a given language lexicon. A principle underlying the growth (or evolution) of those networks is preferential attachment, or the ‘rich-gets-richer’ mechanisms, according to which words with many phonological neighbors (or links) are the main beneficiaries of future growth opportunities. Due to their limited number of words, language lexica constitute node-constrained networks where growth cannot keep increasing in a linear way; hence, preferential attachment is likely mitigated by certain factors. The present study investigated aging effects (i.e., a word’s finite time span of being active in terms of growth) in an evolving phonological network of English as a second language. It was found that phonological neighborhoods are constructed by one large initial lexical spurt, followed by sublinear growth spurts that eventually lead to very limited growth in later lexical spurts during network evolution, all the while obeying the law of preferential attachment. An analysis of the strength of phonological relationships between phonological word forms revealed a tendency to attach more distant phonological neighbors in the lower proficiency levels, while phonologically more similar neighbors enter phonological neighborhoods at more advanced levels of English as a second language. Overall, the findings suggest an aging effect in growth that favors younger words. In addition, beginning learners seem to prefer the acquisition of phonological neighbors that are easier to discriminate. Implications for the second language lexicon include leveraged learning mechanisms, learning bouts focussed on a smaller range of phonological segments, and involve questions concerning lexical processing in aging networks.
- Rights:
- Creative Commons - Attribution-NoDerivatives 4.0 International (CC BY-ND 4.0), http://creativecommons.org/licenses/by-nd/4.0/, and PUB
1833. Aging, hormones and receptors
- Creator:
- Hill, Martin, Třískala, Zdeněk, Honců, Pavla, Krejčí, Milada, Kajzar, Jiří, Bičíková, Marie, Ondřejíková, Leona, Jandová, Dobroslava, and Sterzl, Ivan
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- stárnutí, aging, small molecules, hypothalamic-pituitary-adrenal axis, life-management, hormonal receptors, 14, and 612
- Language:
- English
- Description:
- Ageing is accompanied by deterioration in physical condition and a number of physiological processes and thus a higher risk of a range of diseases and disorders. In particular, we focused on the changes associated with aging, especially the role of small molecules, their role in physiological and pathophysiological processes and potential treatment options. Our previously published results and data from other authors lead to the conclusion that these unwanted changes are mainly linked to the hypothalamic-pituitary-adrenal axis can be slowed down, stopped, or in some cases even reversed by an appropriate treatment, but especially by a life-management adjustment., Martin Hill, Zdeněk Třískala, Pavla Honců, Milada Krejčí, Jiří Kajzar, Marie Bičíková, Leona Ondřejíková, Dobroslava Jandová, Ivan Sterzl., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1834. Aging-induced down-regulation of PKA/BKCa pathway in rat cerebral arteries
- Creator:
- Li, Na, Shi, Ruixiu, Ye, Yang, Zhang, Yingying, Zhang, Yumeng, Wang, Zhizhi, Gu, Ying, Yin, Yongxiang, Chen, Daozhen, and Tang, Jiaqi
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- cerebral artery, large-conductance Ca2+-activated-K+ channel, aging, vessel dilatation, and protein kinase A
- Language:
- English
- Description:
- The incidence of cerebrovascular diseases increases significantly with aging. This study aimed to test the hypothesis that aging may influence the protein kinase A (PKA)-dependent vasodilation via RyR/BKCa pathway in the middle cerebral arteries (MCA). Male Sprague-Dawley rats were randomly divided into control (4-6 month-old) and aged (24-month-old) groups. The functions of MCA and ion channel activities in smooth muscle cells were examined using myograph system and patch-clamp. Aging decreased the isoproterenol/forskolin-induced relaxation in the MCA. Large-conductance Ca2+-activated-K+ (BKCa) channel inhibitor, iberiotoxin, significantly attenuated the forskolininduced vasodilatation and hyperpolarization in the young group, but not in the aged group. The amplitude and frequency of spontaneous transient outward currents (STOCs) were significantly decreased in the aged group. Single channel recording revealed that the mean open time of BKCa channels were decreased, while an increased mean closed time of BKCa channels were found in the aged group. The Ca2+/voltage sensitivity of the channels was decreased accompanied by reduced BKCa α and β1-subunit, the expression of RyR2, PKA-Cα and PKA-Cβ subunits were also declined in the aged group. Aging induced down-regulation of PKA/BKCa pathway in cerebral artery in rats. The results provides new information on further understanding in cerebrovascular diseases resulted from agerelated cerebral vascular dysfunction.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1835. Agreement of molecular biology and morphology methods in sex determination of human bones from Žatec cemetery (11th - 13th century AD) /
- Type:
- text and studie
- Subject:
- Archeologie, Fyzická antropologie, antropologie, pohřebiště, and archeologie, výzkumy
- Language:
- English
- Description:
- Shoda v určení pohlaví při aplikaci molekulárně biologických a morfologických metod na lidské kosterní pozůstatky ze Žatce 11.-13. století.
- Rights:
- unknown
1836. Agresivní hemangiom obratle
- Creator:
- Kostyšyn, Roman, Pleskačová, Z., and Málek, Václav
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, přehledy, and TEXT
- Subject:
- hemangiom--patologie--radiografie--terapie, diferenciální diagnóza, nádory páteře--patologie--radiografie--terapie, popis nemoci, těhotenství - komplikace nádorové, kombinovaná terapie, páteř--chirurgie, embolizace terapeutická, skleroterapie, vertebroplastika, inhibitory angiogeneze, propranolol--farmakologie, výsledek terapie, dospělí, staří, ženské pohlaví, lidé, mužské pohlaví, lidé středního věku, and tomografie rentgenová počítačová
- Language:
- Czech and English
- Description:
- Hemangiom je nejčastější primární benigní nádor páteře typu hamartomu, který nikdy nemalignizuje. V drtivé většině případů se jedná o asymptomatické solitární léze hrudní páteře jakožto náhodné nálezy radiografických vyšetření. Pouze v 1 % případů se hemangiom obratle projeví klinicky a agresivita této benigní léze pak spočívá v expanzivním chování nádorové tkáně či v důsledku patologické fraktury obratle. Klinickými příznaky potom jsou především dorzalgie, v pokročilých případech pak známky kořenové nebo míšní komprese. Radiodiagnostika je poměrně snadná, protože hemangiom obratle vykazuje zcela typické grafické příznaky, pro potvrzení diagnózy agresivního hemangiomu obratle jsou stanovena grafická kritéria. Spektrum léčebných modalit je velmi široké od konzervativní léčby přes hodně využívanou vertebroplastiku po radikální chirurgickou léčbu. Komplementárně jsou často využívány embolizační výkony, alkoholová sklerotizace a lokální radioterapie. Agresivní hemangiom obratle je poměrně velmi vzácná diagnóza. Proto zatím neexistují velké soubory či klinické studie, podle kterých by bylo možné stanovit optimální terapeutický postup., Hemangioma is the most common primary benign hamartoma type spine tumor. Malignant degeneration has never been reported. In the majority of cases, this is an asymptomatic solitary lesion of the thoracic spine found incidentally during a radiographic examination. Only 1% of cases manifests clinically and this benign lesion is considered aggressive because of the expansive nature of the tumor and because it may cause pathological fracture of the vertebrae. Clinical symptoms then include dorsalgia and either root or spinal neurological symptoms. Radiological diagnosis is relatively easy because vertebral hemangioma is associated with quite typical graphic signs; graphic criteria to confirm the diagnosis of aggressive vertebral hemangioma have been clearly defined. The range of treatment options is very wide, from conservative treatment through frequently used vertebroplasty to radical surgical treatment. Embolization procedures, alcohol sclerotherapy and local radiotherapy are often used as complementary procedures. Aggressive vertebral hemangioma is a relatively rare diagnosis, so far there are no large cohorts or clinical studies from which it would be possible to determine an optimal therapeutic approach. Key words: hemangioma – vertebroplasty – angiogenesis inhibitors – angiomatosis – propranolol The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers., and R. Kostyšyn, Z. Pleskačová, V. Málek
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1837. Agricultural policy-induced landscape changes: effects on carabid abundance and their biocontrol potential
- Creator:
- Ameixa, Olga and Kindlmann, Pavel
- Type:
- article, model:article, and TEXT
- Subject:
- Agricultural intensification, biocontrol, density, diversity, species richness, food webs, and predatory pressure
- Language:
- English
- Description:
- One of the most important services provided by biodiversity is thought to be the biological control of pests in agricultural landscapes, including aphids on cereals. The food webs potentially contributing to biological control of aphids primarily consist of polyphagous predators, parasitoids and pathogens. The problems of aphid pests have increased greatly since the 1970-ies, possibly as an effect of agricultural intensification, which is thought to have reduced diversity and abundance of these predators and parasites and consequently their biocontrol potential. The main objective of this study was to test this by measuring this potential for biological control of aphids, and relate it to agricultural intensification and predator abundance. We selected 30 farms distributed along agricultural intensification gradients, based on the amount of fertilizers applied per hectare. Estimates of ground-living predator density were obtained using pitfall trapping over a one-week period. Traps were placed inside the cereal fields, 10 m from the margin, in 2 replicates per field. Predation risk due to ground-living predators (biocontrol potential) was estimated by monitoring removal of aphids glued to labels. This was done in the same fields, in the immediate vicinity of the traps, over a period of 2 days. The proportion of aphids eaten per unit time was the response variable. We present the correlations between intensity of agricultural exploitation, predator abundance and biocontrol potential. The outcomes are not straightforward in that intensification begets a reduction in predator density and biocontrol potential. We discuss the potential confounding issues that might have affected our results.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1838. Ahmad Abdel-Hamid Youssef, From Pharaoh´s Lips. Ancient Egyptian Language in the Arabic of Today
- Creator:
- Vymazalová, Hana
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1839. Ailinella mirabilis gen. n., sp. n. (Eucestoda: Pseudophyllidea) from Galaxias maculatus (Pisces: Galaxiidae) in the Andean-Patagonian region of Argentina
- Creator:
- Pertierra, Alicia A. Gil de and Semenas, Liliana G.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Pseudophyllidea, Triaenophoridae, Ailinella mirabilis, microtriches, tumuli, Galaxias maculatus, and Patagonia
- Language:
- English
- Description:
- Ailinella gen. n. (Pseudophyllidea: Triaenophoridae) is proposed to accommodate Ailinella mirabilis sp. n. from Galaxias maculatus (Jenyns, 1842), a freshwater fish inhabiting the Andean lakes in Argentinean Patagonia. Ailinella belongs to the Triaenophoridae because it has a marginal genital pore, a follicular vitelline gland, and a ventral uterine pore. The new genus can be distinguished from other triaenophorids by the following combination of characters: a small body size, a low number of proglottides, which are longer than wide, a truncated pyramidal to globular scolex, a rectangular apical disc, presence of the neck, lack of internal longitudinal musculature separating the cortex from the medulla, testes distributed in one central field surrounding the ovary laterally and posteriorly, the vagina predominantly anterior to the cirrus sac, vitelline follicles circum-medullary, the genital pores post-equatorial, a saccate uterus, and operculate eggs. Blade-like spiniform microtriches were present on all tegument surfaces, and tumuli on all surfaces of the scolex and the anterior surface of the neck. Microtriches were characterized according to their size and density, and tumuli according to their size, inter-tumulus distance and density. Ailinella mirabilis is the first cestode described from G. maculatus and the second triaenophorid species recorded from a South American freshwater fish.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1840. Air ejector with a diffuser that includes boundary layer suction
- Creator:
- Dvořák, Václav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- air ejector, diffuser, and boundary layer suction
- Language:
- English
- Description:
- The article deals with axial-symmetric subsonic air-to air ejector with a diffuser adapted for boundary layer suction. The diffuser, which is placed after the mixing chamber of the ejector, has a high divergence angle and is therefore inefficient. To increase efficiency, the diffuser is equipped with a slot enabling boundary layer suction. The effect of boundary layer suction on the airflow in the ejector was measured, as were the static pressure distribution on the mixing chamber wall and ejector characteristics. Both diffuser and ejector efficiency were calculated. Although the efficiency of the diffuser was increased, the efficiency of the ejector itself remained low. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public