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474472. The impact of individual ladybirds (Coccinella septempunctata, Coleoptera: Coccinellidae) on aphid colonies
- Creator:
- Minoretti, Nicole and Weisser, W.
- Type:
- article, model:article, and TEXT
- Subject:
- Coccinella septempunctata, Acyrthosiphon pisum, aphid, predator-prey interaction, foraging, and survival
- Language:
- English
- Description:
- Pea aphids (Acyrthosiphon pisum) have been reported to produce winged offspring in the presence of predatory ladybirds. These offspring may leave host plants by flight after they have developed into winged adults. The inter-generational nature of this response raises the question about the chances of survival of aphids developing in attacked colonies. We studied the behaviour of predatory ladybirds on host plants by releasing adult 7-spot ladybirds (Coccinella septempunctata) on bean plants hosting either no prey individuals or colonies of 10 or 30 pea aphids. Interactions between predator and prey were recorded until the ladybird left the plant. Ladybird patch residence time increased with the number of aphids present on a plant but beetles generally left a plant before all aphids were eaten. The time budget of the ladybirds revealed a high proportion of time not spent in feeding activities. Predation rate was about one aphid killed per 10min residence time in both treatments with aphid-infested plants. Aphids that survived an attack by the predator or that were alarmed when a conspecific was attacked often emigrated from the host plant, and their number was of the same magnitude as the number of aphids killed by the predator. On average, pea aphid numbers at the end of an experiment were reduced to less than a third of the initial value. The results of the experiment show that attack by single ladybirds does on average not cause immediate extinction of small aphid colonies. The short patch residence times of on average less than two hours show that a predator individual that induces winged-offspring production in an aphid colony will not any longer be present in the colony when the induced offspring mature. To understand the adaptiveness of predator-induced wing development in pea aphids the probabilities of subsequent attacks on an aphid colony need to be investigated.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474473. The impact of male-killing bacteria on the evolution of aphidophagous coccinellids
- Creator:
- Majerus, Michael
- Type:
- article, model:article, and TEXT
- Subject:
- Coccinellids, biased sex ratios, male-killing, cytoplasmic bacteria, and reproductive manipulation
- Language:
- English
- Description:
- Many aphidophagous coccinellids harbour male-killing bacteria. These maternally inherited bacteria kill males early in embryogenesis, female offspring of infected mothers gaining a large resource advantage from the consumption of their dead brothers. In this paper, the diversity of male-killing bacteria and their coccinellid hosts will be briefly reviewed. Thereafter, the impact that invasion by male-killers has on coccinellid hosts will be addressed in two ways. First, the selective effects due to the loss of male progeny, and the intra-genomic conflict resulting from the cytoplasmic inheritance of the bacteria will be considered. Reductions in mitochondrial diversity, effects on clutch sizes and the evolution of male-killer suppresser systems will be discussed. Second, the impact of female biased population sex ratios on the evolution of reproductive strategies and the primary sex ratio will be investigated. Preliminary results suggesting changes in male investment per copulation, reductions in female testing behaviour of males, and male biases in the progenic sex ratios of some uninfected male lines will be presented. Avenues for future work will be outlined.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474474. The impact of selected dytokines in the follow-up of normal pressure hydrocephalus
- Creator:
- Sosvorova, L., Milan Mohapl, Josef Včelák, Hill, M., Vítků, J., and Richard Hampl
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, cytokiny, mozkomíšní mok, neurodegenerace, cytokines, cerebrospinal fluid, neurodegeneration, normal pressure hydrocephalus, ventriculoperitoneal shung, 14, and 612
- Language:
- English
- Description:
- Cytokines are widely known mediators of inflammation accompanying many neurodegenerative disorders including normal pressure hydrocephalus (NPH). NPH is caused by impaired cerebrospinal fluid (CSF) reabsorption and treated by surgical shunt insertion. The diagnostics is still complicated and the shunt effect is not durable; after several years, dementia may develop. In the clinical practice, biomarkers support the diagnostics as well as the further time course of many neurodegenerative diseases. Until recently, no reliable biomarker for NPH was evaluated. The attempt of this review was to make a survey concerning cytokines as possible NPH markers. Among all reviewed cytokines, the most promising are CSF IL-10 and IL-33, enabling to follow-up the disease progression and monitoring the effectiveness of the shunt insertion., L. Sosvorova, M. Mohapl, J. Vcelak, M. Hill, J. Vitku, R. Hampl., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474475. The impact of sound exposure on heart rate variability in adolescent students
- Creator:
- Veternik, M, Ingrid Tonhajzerová, Jiří Míšek, Jakusova, V, Henrieta Hudečková, and Ján Jakuš
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- autonomní nervový systém, zvuk, nos, autonomic nervous system, noise, heart rate variability, cardiac regulation, 14, and 612
- Language:
- English
- Description:
- Previous studies of physiological responses to music and noise showed the effect on the autonomic nervous system. The heart rate variability (HRV) has been used to assess the activation of the sympathetic and the parasympathetic nervous systems. The present study was aimed to examine HRV with exposure to four sine-wave pure tones (20 Hz, 50 Hz, 2 kHz and 15 kHz) in an environment where the sound intensity exceeded level 65 dB (A-weighted). The participants (20 adolescent girls) were lying in supine position during exposure protocol divided into 6 periods, the first time with generated sounds and the second time without sounds. In the protocol without sound exposure, the low frequency band of the HRV spectrum was increased compared to the basal state before examination (period_1: 6.05±0.29 ms2 compared to period_5: 6.56±0.20 ms2, p<0.05). The significant increase of root Mean Square of the Successive Differences (rMSSD, period_1: 4.09±0.16 s compared to period_6: 4.33±0.12 s, p<0.05) and prolongation of R to R peak (RR) interval (period_1: 889±30 ms compared to period_5: 973±30 ms, p<0.001) were observed in the protocol without sound exposure comparing to the protocol with sound exposure where only bradycardia was observed. Contrary to rather polemical data in literature our pilot study suggests that sounds (under given frequencies) have no impact on the heart rate variability and cardiac autonomic regulation., M. Veternik, I. Tonhajzerova, J. Misek, V. Jakusova, H. Hudeckova, J. Jakus., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474476. The impact of teaching physical education to Czech school children using progressive teaching approaches: findings of a four-year study
- Creator:
- Frömel, Karel
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474477. The impact of the Czech New Civil code on domain names – legal (de)trashing of not only domain names
- Creator:
- Pelikánová MacGregor, Radka
- Type:
- article, model:article, and TEXT
- Subject:
- czech new Civil Code, domain name, item, and property
- Language:
- English
- Description:
- The recent Czech re-codification of the Private law is amassive legislative move performed through a set of statutes and other instruments. The flagship of this flotilla, the Act No. 89/2012 Coll., the Czech New Civil Code has significantly re-shaped the Czech private legal framework and reached even the fundamental principles and concepts. For instance, the reinforced mandate of good morals and the reviewed delineation of in rem rights have the potential to change the meaning and regime of virtually all assets, including virtual domain names. The former discussion whether the domain name is an item, aright, something else or noth- ing and whether a domain name can be owned or held or neither is not expressly resolved by the New Civil Code. There are at least two opinion streams – one interpreting the new regulation as an endorsement of the in rem regime of domain names and another interpreting the new regulation as a clear rejection of the in rem regime of domain names. What exactly does the New Civil Code tell us and how should we interpret it? Aconsistent and open-minded approach leads to aset of (semi)conclusions bringing light in this extremely important and confusing arena and advocating for placing domain names, as well as the Roman law own- ership triad, from the shadow to the sunny side.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474478. The impact of tropospheric mapping function on PPP determination for one-month period
- Creator:
- Nistor, Sorin, Suba, Norbert-Szabolcs, and Buda, Aurelian-Stelian
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- geodynamika, geodynamics, PPP, mapping function, postfit residuals, standard deviation, GNSS, repeatability, 7, and 551
- Language:
- English
- Description:
- When using the PPP method, it is recommended to take into account the tropospheric influences for obtaining reliable estimates. Global Navigation Satellite System (GNSS) observations taken at low elevation suffer more strongly from atmospheric, antenna phase center variation and multipath effects, hence the observations are noisier than those at higher elevation angle, but they are essential to decorrelate the estimated station height and tropospheric zenith delay (ZTD). To relate the ZTD in the direction of an observation, the so-called mapping function (MF) are used. In this article the influence of different mapping function was studieds such as: Niell mapping function (NMF), Global Mapping Function (GMF) in conjunction with the Global Pressure and Temperature 2-GPT2, Vienna Mapping Function 1 and no mapping function. The MF were used at different elevation cutoff angles - 50 , 70, 100 and 150. The impact was analyzed: a) on the postfit residuals of the ionospheric free combination for phase (LC) and for pseudorange (PC), b) daily variability for North, East and Up component; c) evaluation of coordinates repeatability and how they are affected by the changes of the cutoff elevation angle and mapping function. The analyzed data was taken from 4 EUREF stations for a period of one month - October 2015. By using the VMF1 mapping function, the lowest value was obtained for the postfit residuals of the LC combination for all the stations. The difference in daily variation between each individual solution for the horizontal component is at the level of ~0.3 ÷ 0.5 mm, with smaller effect on the East component compared to North, whereas the Up component is at the level of ~1.0 ÷ 1.5 mm. The standard deviation (SD) is used as a measure of station position repeatability and the results suggested that for high precision determination a cutoff elevation angle of 100 should be used., Sorin Nistor, Norbert-Szabolcs Suba and Aurelian-Stelian Buda., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474479. The impact of unbounded swings of the forcing term on the asymptotic behavior of functional equations
- Creator:
- Singh, Bhagat
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- oscillatory, nonoscillatory, exterior domain, elliptic, and functional equation
- Language:
- English
- Description:
- Necessary and sufficient conditions have been found to force all solutions of the equation \[ (r(t)y^{\prime }(t))^{(n-1)} + a(t)h(y(g(t))) = f(t), \] to behave in peculiar ways. These results are then extended to the elliptic equation \[ |x|^{p-1} \Delta y(|x|) + a(|x|)h(y(g(|x|))) = f(|x|) \] where $ \Delta $ is the Laplace operator and $p \ge 3$ is an integer.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
474480. The impact of using multi-dimensional and combinatory vague terms on the possibility of formulating sorites paradoxes
- Creator:
- Štěpánek, Jan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- combinatory vagueness, linear vagueness, multi-dimensional vagueness, paradox, paradox of the heap, sorites, and vagueness
- Language:
- Slovak
- Description:
- We cannot definitely determine precise boundaries of application of vague terms like ''tall''. Since it is only a height of a person that determines whether that person is tall or not, we can count ''tall'' as an example of a linear vague term. That means that all objects in a range of significance of ''tall'' can be linearly ordered. Linear vague terms can be used to formulate three basic versions of the sorites paradox – the conditional sorites, the mathematical induction sorites, and the line-drawing sorites. In this paper I would like to explore a possibility of formulating sorites paradoxes with so called multi-dimensional and combinatory vague terms – terms for which it is impossible to create a linear ordering of all objects in their range of significance. Therefore, I will show which adjustments must be made and which simplifications we must accede to in order to formulate any version of the sorites paradox with multi-dimensional or combinatory vague terms. I will also show that only the conditional version of the sorites paradox can be construed with all three kinds of vague terms., Nemůžeme rozhodně určit přesné hranice aplikace neurčitých termínů jako ,,vysoký''. Jelikož je to pouze výška osoby, která určuje, zda je tato osoba vysoká nebo ne, můžeme jako příklad lineárního neurčitého termínu počítat ,,vysoký''. To znamená, že všechny objekty v rozsahu významu ,,vysokého'' mohou být lineárně uspořádány. Lineární neurčité termíny mohou být použity pro formulaci tří základních verzí paradoxů soritů - podmíněných soritů, matematických indukčních soritů a soritů pro kreslení čar. V této práci bych chtěl prozkoumat možnost formulování paradoxů soritů s takzvanými vícerozměrnými a kombinatorickými neurčitými termíny - termíny, pro které není možné vytvořit lineární uspořádání všech objektů v rozsahu jejich významu. Proto, Ukážu, jaké úpravy je třeba provést a jaká zjednodušení musíme přistoupit, abychom mohli formulovat jakoukoli verzi paradoxů soritů s vícerozměrnými nebo kombinatorickými neurčitými termíny. Ukážu také, že pouze podmíněnou verzi paradoxu soritů lze chápat se všemi třemi druhy neurčitých termínů., and Jan Štěpánek
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public