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1722. Algebraic integrability for minimum energy curves
- Creator:
- Yudin, Ivan and Silva Leite, Fátima
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Darboux polynomials, drag power, Euler-Lagrange equations, grading, integrability, and vector fields
- Language:
- English
- Description:
- This paper deals with integrability issues of the Euler-Lagrange equations associated to a variational problem, where the energy function depends on acceleration and drag. Although the motivation came from applications to path planning of underwater robot manipulators, the approach is rather theoretical and the main difficulties result from the fact that the power needed to push an object through a fluid increases as the cube of its speed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1723. Algebraic solution to box-constrained bi-criteria problem of rating alternatives through pairwise comparisons
- Creator:
- Krivulin, Nikolai
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- idempotent semifield, tropical optimization, constrained bi-criteria decision problem, Pareto-optimal solution, box constraints, and pairwise comparisons
- Language:
- English
- Description:
- We consider a decision-making problem to evaluate absolute ratings of alternatives that are compared in pairs according to two criteria, subject to box constraints on the ratings. The problem is formulated as the log-Chebyshev approximation of two pairwise comparison matrices by a common consistent matrix (a symmetrically reciprocal matrix of unit rank), to minimize the approximation errors for both matrices simultaneously. We rearrange the approximation problem as a constrained bi-objective optimization problem of finding a vector that determines the approximating consistent matrix, and then represent the problem in terms of tropical algebra. We apply methods and results of tropical optimization to derive an analytical solution of the constrained problem. The solution consists in introducing two new variables that describe the values of the objective functions and allow reducing the problem to the solution of a system of parameterized inequalities constructed for the unknown vector, where the new variables play the role of parameters. We exploit the existence condition for solutions of the system to derive those values of the parameters that belong to the Pareto front inherent to the problem. Then, we solve the system for the unknown vector and take all solutions that correspond to the Pareto front, as a complete solution of the bi-objective problem. We apply the result obtained to the bi-criteria decision problem under consideration and present illustrative examples.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1724. Algebras and spaces of dense constancies
- Creator:
- Bella, Angelo, Martinez, Jorge, and Woodward, Scott D.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- space and algebra of dense constancy and $c$-spectrum
- Language:
- English
- Description:
- A DC-space (or space of dense constancies) is a Tychonoff space $X$ such that for each $f\in C(X)$ there is a family of open sets $\lbrace U_i\: i\in I\rbrace $, the union of which is dense in $X$, such that $f$, restricted to each $U_i$, is constant. A number of characterizations of DC-spaces are given, which lead to an algebraic generalization of the concept, which, in turn, permits analysis of DC-spaces in the language of archimedean $f$-algebras. One is led naturally to the notion of an almost DC-space (in which the densely constant functions are dense), and it is shown that all metrizable spaces have this property.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1725. Algesthesia after epileptic seizure
- Creator:
- Jan Mareš and Richard Rokyta
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Patologie. Klinická medicína, patologie, epileptické záchvaty, analgezie, krysa obecná, pathology, epileptic seizures, analgesia, Rattus rattus, nociception, flurothyl, postictal analgesia, 14, and 616
- Language:
- English
- Description:
- The consequences of epileptic seizures related to postictal inhibition in early postictal period include postictal analgesia. We studied this phenomenon over 96 h following flurothyl-induced seizures in adult male Wistar rats. Nociception of control (no seizure) and seizured groups were tested using the plantar and von Frey hair tests. We determined latency of forepaw and hind paw reactions using plantar tests and the number of von Frey hairs reactions. Shortly after seizures, longer plantar test latencies were seen relative to the control group. Before the seizures the plantar test reaction times were significantly shorter in forepaws than in hind paws. The effect disappeared post-seizure and surprisingly, it also disappeared at the corresponding time in controls; it reappeared after 48 h in the seizure group and after 24 h in controls. Differences in the von Frey hairs test occurred at 5 and 60 min post-seizure, however, these differences could not be explained by limb anatomy; although, different thermal and mechanical nociception mechanisms could be significant. The unexpected reactions in controls could be related to brief social and physical interactions between the two groups. and J. Mareš, R. Rokyta.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1726. Alginate matrices for protein delivery: a short review
- Creator:
- Wawrzyńska, E and Dana Kubies
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- algináty, růstové faktory, alginates, growth factors, biomaterials, protein release, growth factor release, 14, and 612
- Language:
- English
- Description:
- Growth factors are powerful molecules that regulate cellular growth, proliferation, healing, and cellular differentiation. A delivery matrix that incorporates growth factors with high loading efficiencies, controls their release, and maintains bioactivity would be a powerful tool for regenerative medicine. Alginate has several unique properties that make it an excellent platform for the delivery of proteins. Mild gelling conditions can minimize the risk of protein denaturation; moreover, alginate can serve as protection from degradation until protein release. Various modifications have been proposed to tune alginate binding and release proteins, simultaneously adjusting alginate degradability, mechanical stiffness, swelling, gelation properties and cell affinity. The primary objective of this article is to review the literature related to recent advances in the application of alginate matrices in protein delivery in regenerative medicine. A special emphasis is put on the relevance of delivery of growth factors and chemokine., E. Wawrzyńska, D. Kubies., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1727. Algoritmus operací mnohočetného myelomu a solitárního plazmocytomu páteře
- Creator:
- Hrabálek, Lumír, Wanek, Tomáš, Minařík, Jiří, Bačovský, Jaroslav, Ščudla, Vlastimil, and Vaverka, Miroslav
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, práce podpořená grantem, and TEXT
- Subject:
- algoritmy, mnohočetný myelom--diagnóza--chirurgie--patologie, plazmocytom--diagnóza--chirurgie--patologie, výsledky a postupy - zhodnocení (zdravotní péče), páteř--chirurgie--patologie, měření bolesti, neuralgie--chirurgie, přežití, dospělí, staří, ženské pohlaví, lidé, mužské pohlaví, and lidé středního věku
- Language:
- Czech and English
- Description:
- Mnohočetný myelom (MM) a solitární plazmocytom (SP) jsou nejčastější primární nádory páteře. Léčba MM a SP páteře je komplexní proces, který zahrnuje léčbu kauzální s cílem potlačit nádorový klon a dále léčbu podpůrnou, jejíž součástí je i chirurgická terapie. Operace přispívají k lepší kvalitě života a nabývají na významu a smysluplnosti zejm. díky zlepšené prognóze onemocnění. Navrhli jsme algoritmus operační léčby MM a SP a ten jsme dále prospektivně ověřovali a jeho vyhodnocení bylo cílem této studie. Pacienti byli operováni v průběhu 10 let, minimální doba sledování byl jeden rok. Soubor tvořilo 32 pacientů (20 mužů a 12 žen) s průměrným věkem 61 let. Operováno bylo celkem 61 obratlů. Důvodem k operaci byly projevy útlaku míchy a progredující neurologický deficit (hodnoceno Frankelovou škálou) nebo na konzervativní léčbu nereagující axiální bolest (hodnoceno VAS; Visual Analogue Scale) páteře. Provedena byla některá z těchto operací: vertebroplastika (VP), laminektomie, transpedikulární fixace, somatektomie a jejich kombinace, nebo okcipito‑cervikální fixace. Pooperační VAS a Frankelova škála byly vyhodnoceny za jeden rok, skiagramy a MR jsme provedli a zhodnotili každý jeden rok. U žádného pacienta nenastala lokální recidiva tumoru ani selhání stabilizace na operovaném úseku v celém sledovaném období. Průměrný předoperační VAS byl 6,8 a jeden rok po operaci se průměrný VAS snížil na 1,1. Všechny operační výkony vedly nejen ke kontrole bolesti, ale také k prevenci nebo zlepšení neurologického postižení po celou dobu sledování. Hodnotili jsme náš postup – algoritmus operací, míru radikality a jejich načasování jako optimální pro MM i SP., Multiple myeloma (MM) and solitary plasmacytoma (SP) are the most frequent primary tumors of the spine. Management of the spinal MM and SP is a complex process involving causal treatment to suppress the tumor clone, as well as supportive therapy, including surgery and radiotherapy. Surgery should be considered because of its favourable effect on disease prognosis. We proposed a surgical treatment algorithm in patients with spinal MM and SP and the aim of this article is to present prospective evaluation of this algorithm. Patients undergoing surgical treatment during the past 10 years were included in this study, with the minimum follow-up of one year. A total of 32 patients (20 males and 12 females) with the mean age of 61 years were included. Surgery of 61 vertebrae was performed. The procedures were indicated for progressing neurological deficit (Frankel score) and for axial spinal pain (VAS classification). We performed the following procedures: vertebroplasty, laminectomy, transpedicular fixation, somatectomy, and their combination, or occipito-cervical fixation. Frankel score and VAS was assessed one year after the surgery and X-ray and spinal MRI was performed every year. No local relapses of the tumor or stabilization failure were detected. The mean preoperative VAS was 6.8 and improved to 1.1 one year after the surgery. During the follow up period, we observed positive effect of surgery on pain control and on prevention or improvement of neurological dysfunction. The authors concluded that all surgical procedures, the extent of resection and timing were adequate in all subjects. Key words: multiple myeloma – solitary plasmacytoma –vertebroplasty – transpedicular fixation – somatectomy 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 L. Hrabálek, T. Wanek, J. Minařík, J. Bačovský, V. Ščudla, M. Vaverka
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1728. Alien vascular plants recorded from the Barentsburg and Pyramiden settlements, Svalbard
- Creator:
- Liška , Jiří and Soldán , Zdeněk
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- adventive, allochtonous, Arctic, flora, introduced, non-indigenous, plant invasions, Spitsbergen, and Svalbard
- Language:
- English
- Description:
- A list of alien plant species recorded from Svalbard in the summer of 1988 is presented. Two localities, the Russian settlements of Barentsburg and Pyramiden on the Isfjorden, Spitsbergen, were studied. Prior to this study, almost 60 alien species were recorded from Svalbard by other investigators. During the research reported here, 44 taxa were found, 14 of which are new records for the Svalbard archipelago. Six species are considered to be possibly naturalized; however, it is difficult to assess their naturalization status because of the severity of the climate in the study area. A complete list of species is presented, with information on height and phenological stage of particular specimens. Most of the alien plants recorded at the two settlements belong to the family Brassicaceae.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1729. Alkaline phosphatase activity of duodenal enterocytes after neonatal administration of monosodium glutamate to rats
- Creator:
- Mozeš, Š., Ľudovít Lenhardt, and Martinková, A.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, obezita, obesity, alkaline phosphatase activity, duodenal enterocytes, monosodium glutamate, rat, 14, and 612
- Language:
- English
- Description:
- In the present work neonatal male and female Wistar rats were treated intraperitoneally with monosodium glutamate (MSG 2 mg/kg b.w.) or saline (controls) daily for 4 day after birth. At the age of 30 and 80 days, the alkaline phosphatase activity (AP) in the brush border of individual enterocytes, the body fat content and Lee´s index of obesity were analyzed. Microdensitometrical quantification of AP was significantly increased on day 30 in males (P<0.01) and on day 80 in MSG-treated male and female rats (P<0.001) as compared to the controls. MSG administration also increased the body fat weight and the obesity index significantly (P<0.001) in 80-day-old animals, but was without any significant effect on their food intake. Our results showed that a) neonatal MSG-treatment may significantly change the intestinal function and b) the investigation of the intestinal enzyme activities may be important in further studies on MSG-induced and other forms of obesity., Š. Mozeš, Ľ. Lenhardt, A. Martinková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1730. Alkaline phosphatase as marker of Schistosoma monsoni egg viability
- Creator:
- Giboda, M. and Žďárská, Z.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Schistosoma mansoni, eggs, viability, and alkaline phosphalase
- Language:
- English
- Description:
- A reliable assessment of the viability of schistosome eggs trapped in host tissues is difficult. The use of a coupling azo dye method for the detection of alkaline phosphatase (A1P) in Schistosoma mansoni ova was found to be a specific and sensitive method for differentiating between viable and dead eggs, and can be used in both immature and mature eggs. In fully developed miracidia within an egg, A1P activity was demonstrated in germ cells and in the sensory endings of the neural cells. The embryonating miracidia displayed A1P activity on the body surface and in von Lichienberg’s envelope. The alkaline phosphatase test for egg viability shows increased sensitivity when compared with the more conventional Oogram and Hatching tests.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public