Focusing on the idea that multivalent cations affect SOM matrix and surface, we treated peat and soil samples by solutions of NaCl, CaCl2 or AlCl3. Water binding was characterized with low field 1 H-NMR-relaxometry (20 MHz) and 1 H wideline NMR spectroscopy (400 MHz) and compared to contact angles. From 1 H wideline, we distinguished mobile water and water involved in water molecule bridges (WaMB). Large part of cation bridges (CaB) between SOM functional groups are associated with WaMB. Unexpectedly, 1 H NMRrelaxometry relaxation rates suggest that cross-linking in the Al-containing peat is not stronger than that by Ca. The relation between percentage of mobile water and WaMB water in the context of wettability and 1 H NMR relaxation times confirms that wettability controls the water film surrounding soil particles. Wettability is controlled by WaMB-CaB associations fixing hydrophilic functional groups in the SOM interior. This can lead to severe water repellency. Wettability decreases with increasing involvement of functional groups in CaB-WaMB associations. The results demonstrate the relevance of CaB and WaMB for the dynamics of biogeochemical and hydrological processes under field conditions, as only a few percent of organic matter can affect the physical, chemical, and biological functioning of the entire 3-phase ecosystem.
The chilling and light stresses were experimentally created to explore photosynthesis of Fraxinus mandshurica seedlings in northeast China. Net photosynthetic rate, stomatal conductance, and transpiration rate decreased significantly with the decline of temperature and light. Significant interaction effects of light and chilling were observed on gas exchange of photosynthesis. The minimal fluorescence yield of the dark-adapted state (F0) increased with increasing light and decreasing temperature. Both high and low light stresses induced the decreases of the maximal quantum yield of PSII photochemistry (Fv/Fm), photochemical quenching coefficient (qP), nonphotochemical quenching (NPQ), and electron transport rate. Decline of Fv/Fm and increased F0 were observed under decreasing temperatures. Decreased NPQ and qP at frost temperature suggest that F. mandschurica failed to dissipate excess light energy. No interactive effects of chilling and light on chlorophyll fluorescence parameters suggests that F. mandschurica seedlings might be adapted to combined stresses of light and chilling., X. F. Li, L. Jin, C. Y. Zhu, Y. J. Wen, Y. Wang., and Obsahuje bibliografii
The aim of the present study was to test the hypothesis that chronic hypoxia would aggrav ate hypertension in Ren-2 transgenic rats (TGR), a well-defined monogenetic model of hypertension with increased ac tivity of endogenous renin- angiotensin system (RAS). Systolic blood pressure (SBP) in conscious rats and mean arterial pressure (MAP) in anesthetized TGR and normotensive Hannover Sprague-Dawley (HanSD) rats were determined under normoxia that was either continuous or interrupted by two weeks' hypoxi a. Expression, activities and concentrations of individual components of RAS were studied in plasma and kidney of TGR and HanSD rats under normoxic conditions and after exposure to chronic hypoxia. In HanSD rats two weeks' exposure to chroni c hypoxia did not alter SBP and MAP. Surprisingly, in TGR it de creased markedly SBP and MAP; this was associated with substantial reduction in plasma and kidney renin activities and also of angiotensin II (ANG II) levels, without altering angiotensin-converting enzyme (ACE) activities. Simultaneously, in TGR the exposu re to hypoxia increased kidney ACE type 2 (ACE2) activity and angiotensin 1-7 (ANG 1-7) concentrations as compared with TGR under continuous normoxia. Based on these results, we propose that suppression of the hypertensiogenic ACE-ANG II axis in the circulation and kidney tissue, combined with augmentation of the intrarenal vasodilator ACE2-ANG 1-7 axis, is the main mechanism responsible for the blood pressure-lowering effects of chronic hypoxia in TGR., L. Červenka, J. Bíbová, Z. Husková, Z. Vańourková, H. J. Kramer, J. Herget, Š. Jíchová, J. Sadowski, V. Hampl., and Obsahuje bibliografii
Combining pattern recognition is a promising direction in designing effective classifiers. There are several approaches to collective decision-making, including quite popular voting methods where the decision is a combination of individual classifiers' outputs. The article focuses on the problem of fuser design which uses discriminants of individual classifiers to make a decision. We present taxonomy of proposed fusers and discuss some of their properties. We focus on the fuser which uses weights dependent on classifier and class number, because of a pretty low computational cost of its training. We formulate the problem of fuser learning as an optimization task and propose a solver which has its origin in neural computations. The quality of proposed learning algorithm was evaluated on the basis of several computer experiments, which were carried out on five benchmark datasets and their results confirm the quality of proposed concept.
The comet assay, or single-cell gel electrophoresis (SCGE), is
a sensitive, rapid, relatively simple and inexpensive method for
detecting DNA strand breaks in individual cells. It is used in
a broad variety of applications and as a tool to investigate DNA
damage and repair. The sensitivity and specificity of the assay
are greatly enhanced if the DNA incubated with an enzyme,
which recognizes a specific kind of DNA damage. This damage
induced by oxidative stress plays a pivotal role in many diseases
and in aging. This article is a critical review of the possible
application of the comet assay in some pathological states in
clinical practice. Most of the studies relate to evaluating the
response of an organism to chemotherapy or radiotherapy with
statistically significant evidence of DNA damage in patients. Other
useful applications have been demonstrated for patients with
heart or neurodegenerative diseases. Only a few studies have
been published on the use of this method in critically ill patients,
although its use would be appropriate. There are also other
scenarios where the comet assay could prove to be very useful in
the future, such as in predicting the likelihood of certain
pathological conditions.
The article ‘Comments on the approach to human dignity in case law’ deals with some approaches to the interpretation of human dignity by international and constitutional courts including Czech Constitutional Court. It is the wide-ranging and extensive use of human dignity that certainly is a success of the post-war concept of human dignity as a basis for the protection of rights. On the other hand, the universal applicability of human dignity and it being ambivalently used is criticised for leading to vagueness and relativisation of the basic concept of dignity. However, given that the post-war conception is based on human dignity being the grounds for the human rights granted to all people, the universality of human dignity and its extensive use are the typical attributes thereof. The article describes fields of judicial interpretation of human dignity expressing diverse worlds of constitutional values., Helena Hofmannová., and Obsahuje bibliografické odkazy
People partaking in a conversation can add to the common ground of said conversation by performing different speech acts. That is, they can influence which propositions are presumed to be shared among them. In this paper, I am going to apply the common ground framework to the phenomenon of epistemic injustice. In doing so, I am going to focus on two kinds of speech acts: making assertions and asking certain kinds of questions. And I am going to look at three varieties of epistemic injustice: testimonial injustice, inquiring injus- tice and interpretative injustice. I am going to argue that what all these varieties of epistemic injustice have in common is that they unfairly inhibit the speaker’s ability to add to the common ground in the way intended by her. This in turn negatively affects which conversational roles a speaker can play in a given conversation. Based on these results, I am going to end by looking at some of the harms that epistemic injustice inflicts upon its victims.
The paper deals with the paradoxes of inference and analysis. It attempts to show what is specific about these paradoxes. They have got a lot in common. Often, they are not considered paradoxes in the strict sense at all. Moreover, they both raise the same problem: How can the requirements of correctness and informativeness be both met for inference and for conceptual analysis? The strategies developed to address the problem are similar for both cases. In the paper, I claim that the paradoxes have common origins. This claim is supported by comparing different strategies adopted to resolve the problem. Regarding their origins, both paradoxes share the epistemological framework that is grounded in Aristotle’s theory of science. This is related to the problem of implicit knowledge, which is a variation on a dilemma formulated by Plato in his Meno. Aristotle’s solution to the dilemma of Meno is discussed and considered as another plausible strategy for dealing with the paradoxes of inference and analysis., Příspěvek se zabývá paradoxy odvození a analýzy. Snaží se ukázat, co je na těchto paradoxech specifické. Mají spoustu společného. Často nejsou vůbec považovány za paradoxy. Oba tyto otázky navíc vyvolávají stejný problém: Jak mohou být splněny požadavky na správnost a informativnost pro závěry a pro koncepční analýzu? Strategie vyvinuté pro řešení tohoto problému jsou podobné v obou případech. V příspěvku tvrdím, že paradoxy mají společný původ. Toto tvrzení je podpořeno porovnáním různých strategií přijatých k vyřešení problému. Pokud jde o jejich původ, oba paradoxy sdílejí epistemologický rámec, který je založen na Aristotelově teorii vědy. To souvisí s problémem implicitní znalosti, což je variace na dilema formulované Platónem v jehoMeno . Aristotelovo řešení dilematu Meno je diskutováno a považováno za další přijatelnou strategii pro řešení paradoxů odvození a analýzy., and Karel Šebela