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51.
The paper presents a variant of first order logic for specifying nondeterministic software. Models of the logics are multialgebras,
i.e. multi-sorted algebras with set-valued operations, together with multi-sorted valuations of variables. We allow empty
carrier sets but the valuations are kept total. Terms are interpreted as sets and the usual set of algebraic terms is extended
by an additional construct used for limiting nondeterminism. Atomic formulae are of the form where is a rewrite operator, corresponding semantically to inclusion. For the above logic, we develop two complete deduction systems
in the natural deduction style: a Rasiowa-Sikorski system for sequences of formulae, and a cut-free Gentzen-style sequent
calculus. We also consider the issues of determinism and partiality, proposing alternate solutions to defining the respective
predicates in our logic.
Received: 4 March 1997 / 25 May 1999 相似文献
52.
Anna Maria Białostocka Urszula Klekotka Beata Kalska-Szostko 《Chemical Engineering Communications》2019,206(6):804-814
In this article, characterization of FeNi layers deposited on a Cu plate for variable magnetic field arrangement is shown. Layers were prepared using a simple electrodeposition process, from an aqueous solution of Fe2+ and Ni2+ sulfate salts containing boric acid, an iron activator. By application of variation of current values, times, and external magnetic field orientations, the resultant film quality was examined and the efficiency of the embedded elements was investigated. The studies show differences in the coating morphology and relative composition of ferromagnetic metals (Ni, Fe) electrodeposited on a not ferromagnetic (paramagnetic) metal (Cu). The obtained layers were investigated by Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy. 相似文献
53.
Vadzim I. Nikitsin Beata Backiel-Brzozowska 《International Journal of Heat and Mass Transfer》2012,55(15-16):4318-4322
At present there is no unified, widely recognized method of estimation of the dependency between the liquid transfer coefficient and the moisture content in material. It is possible to determine such relation by several methods requiring long-term and laborious experimental research, expensive apparatus and complex calculating procedures. The original method of determination of the liquid transfer coefficient in building materials is presented in this work. This method is limited to obtaining experimental data of the kinetics of one-way capillary water uptake by specimens and calculations based on the suggested model. Accuracy of the given method was confirmed using experimental results of capillary absorption process of lightweight concrete and ceramic material. Since the suggested method is theoretically grounded and its accuracy is comparable with other known methods and at the same time it is less laborious and cost-consuming, it can be recommended for practical application. 相似文献
54.
55.
The Asteraceae family is one of the largest flowering plant families, with over 1600 genera and 2500 species worldwide. Some of its most well-known taxa are lettuce, chicory, artichoke, daisy and dandelion. The members of the Asteraceae have been used in the diet and for medicine for centuries. Despite their wide diversity, most family members share a similar chemical composition: for example, all species are good sources of inulin, a natural polysaccharide with strong prebiotic properties. They also demonstrate strong antioxidant, anti-inflammatory and antimicrobial activity, as well as diuretic and wound healing properties. Their pharmacological effects can be attributed to their range of phytochemical compounds, including polyphenols, phenolic acids, flavonoids, acetylenes and triterpenes. One such example is arctiin: a ligand with numerous antioxidant, antiproliferative and desmutagenic activities. The family is also a source of sesquiterpene lactones: the secondary metabolites responsible for the bitter taste of many plants. This mini review examines the current state of literature regarding the positive effect of the Asteraceae family on human health. 相似文献
56.
Katarzyna Smolarczyk Beata Mlynarczyk-Bonikowska Ewa Rudnicka Dariusz Szukiewicz Blazej Meczekalski Roman Smolarczyk Wojciech Pieta 《International journal of molecular sciences》2021,22(4)
Sexually transmitted infections (STIs) caused by Neisseria gonorrhoeae, Chlamydia trachomatis and Mycoplasma genitalium are a common cause of pelvic inflammatory disease (PID) which can lead to tubal factor infertility (TFI). TFI is one of the most common causes of infertility, accounting for 30% of female fertility problems. STIs can also have an impact on pregnancy, leading to adverse pregnancy outcomes. Escalating antibiotic resistance in Neisseria gonorrhoeae and Mycoplasma genitalium represents a significant problem and can be therapeutically challenging. We present a comprehensive review of the current treatment options, as well as the molecular approach to this subject. We have given special attention to molecular epidemiology, molecular diagnostics, current and new treatments, and drug resistance. 相似文献
57.
Aneta Stachowicz Anna Winiewska Katarzyna Ku Magdalena Biaas Magdalena omnicka Justyna Toto-uraska Anna Kiepura Kamila Stachyra Maciej Suski Beata Bujak-Giycka Jacek Jawie Rafa Olszanecki 《International journal of molecular sciences》2021,22(11)
Atherosclerosis and nonalcoholic fatty liver disease are leading causes of morbidity and mortality in the Western countries. The renin–angiotensin system (RAS) with its two main opposing effectors, i.e., angiotensin II (Ang II) and Ang-(1–7), is widely recognized as a major regulator of cardiovascular function and body metabolic processes. Angiotensin-converting enzyme 2 (ACE2) by breaking-down Ang II forms Ang-(1–7) and thus favors Ang-(1–7) actions. Therefore, the aim of our study was to comprehensively evaluate the influence of prolonged treatment with ACE2 activator, diminazene aceturate (DIZE) on the development of atherosclerotic lesions and hepatic steatosis in apoE−/− mice fed a high-fat diet (HFD). We have shown that DIZE stabilized atherosclerotic lesions and attenuated hepatic steatosis in apoE−/− mice fed an HFD. Such effects were associated with decreased total macrophages content and increased α-smooth muscle actin levels in atherosclerotic plaques. Moreover, DIZE changed polarization of macrophages towards increased amount of anti-inflammatory M2 macrophages in the atherosclerotic lesions. Interestingly, the anti-steatotic action of DIZE in the liver was related to the elevated levels of HDL in the plasma, decreased levels of triglycerides, and increased biosynthesis and concentration of taurine in the liver of apoE−/− mice. However, exact molecular mechanisms of both anti-atherosclerotic and anti-steatotic actions of DIZE require further investigations. 相似文献
58.
Karina Polak Beata Bergler-Czop Micha Szczepanek Kamila Wojciechowska Aleksandra Frtczak Norbert Kiss 《International journal of molecular sciences》2021,22(9)
Psoriasis is a chronic, immune-mediated inflammatory disease that affects around 125 million people worldwide. Several studies concerning the gut microbiota composition and its role in disease pathogenesis recently demonstrated significant alterations among psoriatic patients. Certain parameters such as Firmicutes/Bacteroidetes ratio or Psoriasis Microbiome Index were developed in order to distinguish between psoriatic and healthy individuals. The “leaky gut syndrome” and bacterial translocation is considered by some authors as a triggering factor for the onset of the disease, as it promotes chronic systemic inflammation. The alterations were also found to resemble those in inflammatory bowel diseases, obesity and certain cardiovascular diseases. Microbiota dysbiosis, depletion in SCFAs production, increased amount of produced TMAO, dysregulation of the pathways affecting the balance between lymphocytes populations seem to be the most significant findings concerning gut physiology in psoriatic patients. The gut microbiota may serve as a potential response-to-treatment biomarker in certain cases of biological treatment. Oral probiotics administration as well as fecal microbial transplantation were most reported in bringing health benefits to psoriatic patients. However, the issue of psoriatic bacterial gut composition, its role and healing potential needs further investigation. Here we reviewed the literature on the current state of the relationship between psoriasis and gut microbiome. 相似文献
59.
60.
Malgorzata Wojtoniszak Beata Zielinska Xuecheng Chen Ryszard J. Kalenczuk Ewa Borowiak-Palen 《Journal of Materials Science》2012,47(7):3185-3190
In this article, we present a fast and simple method to produce TiO2 nanospheres–graphene nanocomposite with high photocatalytic activity under visible and UV light irradiation. TiO2 nanospheres were adsorbed on graphene in sol–gel process. First, titanium (IV) butoxide underwent hydrolysis in graphene
oxide (GO) ethanol solution resulting in TiO2 nanospheres deposition on GO. Next, the material was calcinated to generate the phase transition of TiO2 into anatase and reduce GO to graphene. The detailed characterization of the material was performed via transmission electron
microscopy, energy dispersive X-rays spectrometer, Fourier-transformed infrared spectroscopy, X-ray diffraction, and Raman
spectroscopy. Interestingly, the band-gap energy of the prepared photocatalyst was drastically decreased in comparison with
the commercial photocatalyst P25 from 3.05 to 2.36 eV. This influenced in the activation of the material under visible light
and resulted in high photocatalytic activity in the process of phenol decomposition in visible and UV irradiation. 相似文献