An analytical model of prominence dynamics

Solar prominences are magnetic structures incarcerating cool and dense gas in an otherwise hot solar corona. Prominences can be categorized as quiescent and active. Their origin and the presence of cool gas (~$10^4$K) within the hot (~$10^6$K) solar corona remains poorly understood. The structure and dynamics of solar prominences was investigated in a large number of observational and theoretical (both analytical and numerical) studies. In this paper, an analytic model of quiescent solar prominence is developed and used to demonstrate that the prominence velocity increases exponentially, which means that some gas falls downward towards the solar surface, and that Alfven waves are naturally present in the solar prominences. These theoretical predictions are consistent with the current observational data of solar quiescent prominences.Comment: Update Final Journal Print Version along with other Metadat

Computational fluid dynamics of coupled free/porous regimes: a specialised case of pleated cartridge filter

The multidisciplinary project AEROFIL has been defined and coordinated with the idea of developing novel filter designs to be employed in aeronautic hydraulic systems. The cartridge filters would be constructed using eco-friendly filtration media supported by unconventional disposable or reusable solid components. My main contribution to this project is the development of a robust and cost-effective design and analysis tool for simulating the hydrodynamics in these pleated cartridge filters. The coupled free and porous flow regimes are generally observed in filtration processes. These processes have been the subject of intense investigation for researchers over the decades who are striving hard to resolve some of the critical issues related to the free/porous interfacial constraints and their mathematical representations concerning its industrial applications. [Continues.

Osmotic Gradients Induce Bio-Reminiscent Morphological Transformations in Giant Unilamellar Vesicles

We report observations of large-scale, in-plane and out-of-plane membrane deformations in giant uni- and multilamellar vesicles composed of binary and ternary lipid mixtures in the presence of net transvesicular osmotic gradients. The lipid mixtures we examined consisted of binary mixtures of DOPC and DPPC lipids and ternary mixtures comprising POPC, sphingomyelin and cholesterol over a range of compositions – both of which produce co-existing phases for selected ranges of compositions at room temperature under thermodynamic equilibrium. In the presence of net osmotic gradients, we find that the in-plane phase separation potential of these mixtures is non-trivially altered and a variety of out-of-plane morphological remodeling events occur. The repertoire of membrane deformations we observe display striking resemblance to their biological counterparts in live cells encompassing vesiculation, membrane fission and fusion, tubulation and pearling, as well as expulsion of entrapped vesicles from multicompartmental giant unilamellar vesicles through large, self-healing transient pores. These observations suggest that the forces introduced by simple osmotic gradients across membrane boundaries could act as a trigger for shape-dependent membrane and vesicle trafficking activities. We speculate that such coupling of osmotic gradients with membrane properties might have provided lipid-mediated mechanisms to compensate for osmotic stress during the early evolution of membrane compartmentalization in the absence of osmoregulatory protein machinery

The Conceptual Foundations of Relationship Marketing: Review and Synthesis

The present review is devoted to a rapidly developing area of marketing — relationship marketing. The authors suggest that the conceptual foundations of it are not currently well developed but forecast that it will transform into a discipline in the near future. They outline two approaches to the definition of relationship marketing and provide their own definition, emphasizing such aspects as collaboration, creation and enhancement of value for those who are involved in relationships. The authors trace the origins of relationship marketing, describing the importance of a range of factors that contribute to the increasing importance of relationship marketing today, such as the development of services, communication with the end consumer, etc. A section of this work examines the development of theoretical approaches: the authors argue that marketing originated in economics, which tended to ignore issues related to distribution systems. They also show that questions concerning relationship marketing were considered even before the term itself was introduced. In the final section, the authors touch upon the models that describe processes in relational marketing and analyze its components step-by-step. The authors highlight three core aspects of relational marketing: setting a purpose, choosing parties and program formation. In the conclusion the authors describe three possible levels of future studies in this area — the concept level, model level and process level — and specifics of each level are characterized

A report of new mammalian tapeworm Moniezia osmanabadensis from Capra hircus at Osmanabad district (M.S.) India

The present communication deals with the occurrence of a new mammalian tapeworm Moniezia (B) osmanabadensis n.sp. from Capra hircus (L) in Osmanabad district (M.S.) India. It comes closer to all the known species of the genus Moniezia but differs from all the known species of the genus in having the scolex globular, elongated, mature proglottids Craspedote, testes medium in size, rounded scattered posterior to segment, 170-200 in numbers, cirrus pouch oval, ovary compact, bean shaped, vitelline gland post ovarian

Modular relations involving generalized digamma functions

Generalized digamma functions $\psi_k(x)$, studied by Ramanujan, Deninger, Dilcher, Kanemitsu, Ishibashi etc., appear as the Laurent series coefficients of the zeta function associated to an indefinite quadratic form. In this paper, a modular relation of the form $F_k(\alpha)=F_k(1/\alpha)$ containing infinite series of $\psi_k(x)$, or, equivalently, between the generalized Stieltjes constants $\gamma_k(x)$, is obtained for any $k\in\mathbb{N}$. When $k=0$, it reduces to a famous transformation given on page $220$ of Ramanujan's Lost Notebook. For $k=1$, an integral containing Riemann's $\Xi$-function, and corresponding to the aforementioned modular relation, is also obtained along with its asymptotic expansions as $\alpha\to0$ and $\alpha\to\infty$. Carlitz-type and Guinand-type finite modular relations involving $\psi_j^{(m)}(x), 0\leq j\leq k, m\in\mathbb{N}\cup\{0\},$ are also derived, thereby extending previous results on the digamma function $\psi(x)$. The extension of Guinand's result for $\psi_j^{(m)}(x), m\geq2,$ involves an interesting combinatorial sum $h(r)$ over integer partitions of $2r$ into exactly $r$ parts. This sum plays a crucial role in an inversion formula needed for this extension. This formula has connection with the inversion formula for the inverse of a triangular Toeplitz matrix. The modular relation for $\psi_j'(x)$ is subtle and requires delicate analysis.Comment: 32 pages, submitted for publication; comments are welcome. Corrected the funding information in the first versio