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Search Results: 1 - 10 of 13738 matches for " Anna Brakoniecka-Sikorska "
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Effect of Freezing Conditions on the Ripening Process and the Quality of Cheese
Arnold Reps,Krystyna Wisniewska,Irmina Jarmul,Anna Brakoniecka-Sikorska
Pakistan Journal of Nutrition , 2005,
Abstract: Kortowski cheese (M nster type) was salted for 100, 75, 50 and 25% of their standard salting time, which is 48 hours. Cheese after 3 weeks of ripening and cheese immediately after salting were stored for 6 and 12 months at -27°C. Cheese of lower salting level ripened faster, both after salting and after frozen storage. The process of protein degradation occurred during frozen storage of ripe cheeses. The content of N-amino acid in ripe cheese after frozen storage and in cheese ripening after storage was almost twice as high as in the cheese that ripened after salting. Separations on Sephadex gel confirm the process of protein degradation during frozen storage of cheese. The conducted research indicated that frozen storage is recommended for Kortowski cheese of reduced salt content and the most favourable solution is to conduct the process of cheese ripening after thawing.
Stability for Functional Differential Equations with Delay in Banach Spaces  [PDF]
Anna Kisiolek, Ireneusz Kubiaczyk, Aneta Sikorska-Nowak
Advances in Pure Mathematics (APM) , 2019, DOI: 10.4236/apm.2019.94016
Abstract: In this paper, using Sadovskii’s fixed point theorem and properties of the measure of noncompactness, we obtain asymptotic stability results for solutions of nonlinear differential equation with variable delay. Results presented in this paper extend some previous results due to Burton[1], Becker and Burton[2], Ardjouni and Djoudi [3], and Jin and Luo[4].
Hyperstability of the Fréchet Equation and a Characterization of Inner Product Spaces
Anna Bahyrycz,Janusz Brzd?k,Magdalena Piszczek,Justyna Sikorska
Journal of Function Spaces , 2013, DOI: 10.1155/2013/496361
Abstract: We prove some stability and hyperstability results for the well-known Fréchet equation stemming from one of the characterizations of the inner product spaces. As the main tool, we use a fixed point theorem for the function spaces. We finish the paper with some new inequalities characterizing the inner product spaces. 1. Introduction In the literature there are many characterizations of inner product spaces. The first norm characterization of inner product space was given by Fréchet [1] in 1935. He proved that a normed space is an inner product space if and only if, for all , In the same year Jordan and von Neumann [2] gave the celebrated parallelogram law characterization of an inner product space. Since then numerous further conditions, characterizing the inner product spaces among the normed spaces, have been shown. More than 300 such conditions have been collected in the book of Amir [3]. Many geometrical characterizations are presented in the book by Alsina et al. [4]; for some other see, for example, [5–8]. The results that we obtain are motivated by the notion of hyperstability of functional equations (see, e.g., [9–14]), which has been introduced in connection with the issue of stability of functional equations (for more details see, e.g., [15, 16]). The main tool in the proof of the main theorem is a fixed point result for function spaces from [17] (for related outcomes see [18, 19]). Similar method of the proof has been already applied in [11, 20]. To present the fixed point theorem we introduce the following necessary hypotheses ( stands for the set of nonnegative reals and denotes the family of all functions mapping a set into a set ).(H1) is a nonempty set, is a Banach space, and functions and are given.(H2) is an operator satisfying the inequality (H3) is defined by Now we are in a position to present the above mentioned fixed point theorem for function spaces (see [17]). Theorem 1. Let hypotheses (H1)–(H3) be valid and functions and fulfil the following two conditions: Then there exists a unique fixed point of with Moreover, We start our considerations from the functional equation that is patterned on (1) and therefore quite often named after Fréchet (see, e.g., [21]). Note that (7) can be written in the form where denotes the Fréchet difference operator defined (for functions mapping a commutative semigroup into a group) by It is easy to check that Such operators were first considered by Fréchet in [22, 23] (we refer to [24] for more information and further references concerning this subject); so, it is still another motivation for (7) to
Human Amniotic Fluid Cells Form Functional Gap Junctions with Cortical Cells
Anna Jezierski,Kerry Rennie,Roger Tremblay,Bogdan Zurakowski,Andreé Gruslin,Marianna Sikorska,Mahmud Bani-Yaghoub
Stem Cells International , 2012, DOI: 10.1155/2012/607161
Abstract: The usage of stem cells is a promising strategy for the repair of damaged tissue in the injured brain. Recently, amniotic fluid (AF) cells have received a lot of attention as an alternative source of stem cells for cell-based therapies. However, the success of this approach relies significantly on proper interactions between graft and host tissue. In particular, the reestablishment of functional brain networks requires formation of gap junctions, as a key step to provide sufficient intercellular communication. In this study, we show that AF cells express high levels of CX43 (GJA1) and are able to establish functional gap junctions with cortical cultures. Furthermore, we report an induction of Cx43 expression in astrocytes following injury to the mouse motor cortex and demonstrate for the first time CX43 expression at the interface between implanted AF cells and host brain cells. These findings suggest that CX43-mediated intercellular communication between AF cells and cortical astrocytes may contribute to the reconstruction of damaged tissue by mediating modulatory, homeostatic, and protective factors in the injured brain and hence warrants further investigation. 1. Introduction Recent advances in regenerative medicine have boosted efforts to explore the therapeutic potentials of stem cells to repair damaged tissue in the injured brain (reviewed in [1–4]). In particular, the transplantation of embryonic stem cells [5], fetal neural stem or progenitor cells [6–8], or bone-marrow-derived stem cells [9, 10] into the injured brain has been explored extensively. However, human embryonic stem (ES) cells and fetal neural stem cells are subject to ethical considerations and the risk of tumor development, whereas adult neural stem cells have limited proliferation capabilities and lineage restriction. Therefore, other stem cell sources, such as human amniotic fluid (AF) [11–13], are being considered for therapeutic applications. There is evidence that AF contains stem cell subpopulation(s) [14] isolated based on c-Kit (CD117–the receptor for stem cell factor [15]) expression, which share some of the characteristics of embryonic and adult stem cells [14]. For instance, several reports have shown that AF cells can differentiate along the adipogenic and osteogenic [16–18], myogenic [19, 20], and endothelial [21] pathways. Furthermore, AF cells have also been shown to harbour the potential for neurogenic differentiation, using different induction protocols [14, 18, 22–25]; however, the proof that these cells can differentiate into functional neurons remains elusive
Oligomerization of ZFYVE27 (Protrudin) Is Necessary to Promote Neurite Extension
D. V. Krishna Pantakani, Marta M. Czyzewska, Anna Sikorska, Chiranjeevi Bodda, Ashraf U. Mannan
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0029584
Abstract: ZFYVE27 (Protrudin) was originally identified as an interacting partner of spastin, which is most frequently mutated in hereditary spastic paraplegia. ZFYVE27 is a novel member of FYVE family, which is implicated in the formation of neurite extensions by promoting directional membrane trafficking in neurons. Now, through a yeast two-hybrid screen, we have identified that ZFYVE27 interacts with itself and the core interaction region resides within the third hydrophobic region (HR3) of the protein. We confirmed the ZFYVE27's self-interaction in the mammalian cells by co-immunoprecipitation and co-localization studies. To decipher the oligomeric nature of ZFYVE27, we performed sucrose gradient centrifugation and showed that ZFYVE27 oligomerizes into dimer/tetramer forms. Sub-cellular fractionation and Triton X-114 membrane phase separation analysis indicated that ZFYVE27 is a peripheral membrane protein. Furthermore, ZFYVE27 also binds to phosphatidylinositol 3-phosphate lipid moiety. Interestingly, cells expressing ZFYVE27ΔHR3 failed to produce protrusions instead caused swelling of cell soma. When ZFYVE27ΔHR3 was co-expressed with wild-type ZFYVE27 (ZFYVE27WT), it exerted a dominant negative effect on ZFYVE27WT as the cells co-expressing both proteins were also unable to induce protrusions and showed cytoplasmic swelling. Altogether, it is evident that a functionally active form of oligomer is crucial for ZFYVE27 ability to promote neurite extensions.
Bilateral Facial Palsy in Rapidly Progressive Course of Wegener’s Granulomatosis: A Case Report
Anna Roszkowska,Monika Morawska-Kochman,Hanna Temporale,Ma?gorzata Sikorska-?uk,Tomasz Kr?cicki
Case Reports in Otolaryngology , 2013, DOI: 10.1155/2013/875108
Abstract: Introduction. Wegener’s granulomatosis belongs to a group of systemic vasculitis diseases, which is characterized by necrotizing vasculitis and presence of granulomas. In a lot of cases, the first symptoms of the disease are observed in the head and neck region, but the bilateral facial nerve palsy occurs very rarely. Objective. The objective of our report was to describe the unusual course of Wegener’s granulomatosis with the bilateral facial nerve paralysis, which subsided after application of steroids and immunosuppressive therapy in combination with surgical treatment. Results and Conclusions. Hearing loss may precede other symptoms in Wegener’s granulomatosis. Ear pain and otorrhea may suggest the diagnosis of bacterial purulent otitis media and delay the proper diagnosis. In the presented case, considering the clinical course, it was necessary to apply both pharmacological and surgical treatments. 1. Introduction Wegenr’s granulomatosis (WG) is a rare systemic autoimmune disease. It is estimated that in Europe there are 25–150 individuals per million suffering from WG and 5–10 new cases per million annually [1]. The increased incidence is recorded in the Scandinavian countries, compared to the countries of southern Europe. Using the “Northsouth” factor, in Norway an average of 12 new cases per million inhabitants per year was recorded and in Spain four times less 3 per million [2]. The new nomenclature defines this disease as granulomatosis with polyangiitis—GPA [3]. This name better reflects the nature of this pathology. granulomatosis refers to necrotizing granulomatous vasculitis, and polyangiitis concerns mainly small-diameter vessels belonging to the group of diseases called microscopic polyangiitis MPA [4]. The disease occurs in both young and adults, with no gender predilection. The average age at diagnosis is 40 [5, 6]. Changes are located typically in both upper and lower respiratory tract and in kidneys (rapidly progressive glomerulonephritis). Depending on the number of affected organs, there are two forms of the disease, isolated form and generalized form. Any organ can be affected. Occasionally, it can be the nervous system, gastrointestinal tract, heart, eyeball, osteoarticular system, and mammary gland [1, 7]. Current treatment regimens based on combination therapy with steroids and immunosuppressive drugs (cyclophosphamide, methotrexate) allow for remission in 70–80% of cases [2, 8, 9]. Lack of treatment might be fatal in 80–82% patients in the first year after diagnosis [9, 10]. Patients with WG have an average survival of 5
Association of HFE Gene Mutations With Liver Cirrhosis Depends on Induction of Iron Homeostasis Disturbances
Katarzyna Sikorska
Hepatitis Monthly , 2012,
Generalized orthogonal stability of some functional equations
Sikorska Justyna
Journal of Inequalities and Applications , 2006,
Abstract: We deal with a conditional functional inequality , where is a given orthogonality relation, is a given nonnegative number, and is a given real number. Under suitable assumptions, we prove that any solution of the above inequality has to be uniformly close to an orthogonally additive mapping , that is, satisfying the condition . In the sequel, we deal with some other functional inequalities and we also present some applications and generalizations of the first result.
Existence theory for nonlinear volterra integral and differential equations
Sikorska Aneta
Journal of Inequalities and Applications , 2001,
Abstract: In this paper we prove the existence theorems for the integrodifferential equation where in first part are functions with values in a Banach space and the integral is taken in the sense of Bochner. In second part are weakly–weakly sequentially continuous functions and the integral is the Pettis integral. Additionaly, the functions and satisfy some boundary conditions and conditions expressed in terms of measure of noncompactness or measure of weak noncompactness.
On Some Fixed Point Theorems for 1-Set Weakly Contractive Multi-Valued Mappings with Weakly Sequentially Closed Graph  [PDF]
Afif Ben Amar, Aneta Sikorska-Nowak
Advances in Pure Mathematics (APM) , 2011, DOI: 10.4236/apm.2011.14030
Abstract: In this paper we prove Leray-Schauder and Furi-Pera types fixed point theorems for a class of multi-valued mappings with weakly sequentially closed graph. Our results improve and extend previous results for weakly sequentially closed maps and are very important in applications, mainly for the investigating of boundary value problems on noncompact intervals.
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