Generalized Mittag-Leffler functions in the theory of finite-size scaling for systems with strong anisotropy and/or long-range interaction

The difficulties arising in the investigation of finite-size scaling in $d$--dimensional O(n) systems with strong anisotropy and/or long-range interaction, decaying with the interparticle distance $r$ as $r^{-d-\sigma}$ ($0<\sigma\leq2$), are discussed. Some integral representations aiming at the simplification of the investigations are presented for the classical and quantum lattice sums that take place in the theory. Special attention is paid to a more general form allowing to treat both cases on an equal footing and in addition cases with strong anisotropic interactions and different geometries. The analysis is simplified further by expressing this general form in terms of a generalization of the Mittag-Leffler special functions. This turned out to be very useful for the extraction of asymptotic finite-size behaviours of the thermodynamic functions.Comment: Accepted for publication in J. Phys. A: Math. and Gen.; 14 pages. The manuscript has been improved to help reader

Efficiency of antenatal care and childbirth services in selected primary health care facilities in rural Tanzania : a cross-sectional study

Background: Cost studies are paramount for demonstrating how resources have been spent and identifying opportunities for more efficient use of resources. The main objective of this study was to assess the actual dimension and distribution of the costs of providing antenatal care (ANC) and childbirth services in selected rural primary health care facilities in Tanzania. In addition, the study analyzed determining factors of service provision efficiency in order to inform health policy and planning. Methods: This was a retrospective quantitative cross-sectional study conducted in 11 health centers and dispensaries in Lindi and Mtwara rural districts. Cost analysis was carried out using step down cost accounting technique. Unit costs reflected efficiency of service provision. Multivariate regression analysis on the drivers of observed relative efficiency in service provision between the study facilities was conducted. Reported personnel workload was also described. Results: The health facilities spent on average 7 USD per capita in 2009. As expected, fewer resources were spent for service provision at dispensaries than at health centers. Personnel costs contributed a high approximate 44% to total costs. ANC and childbirth consumed approximately 11% and 12% of total costs; and 8% and 10% of reported service provision time respectively. On average, unit costs were rather high, 16 USD per ANC visit and 79.4 USD per childbirth. The unit costs showed variation in relative efficiency in providing the services between the health facilities. The results showed that efficiency in ANC depended on the number of staff, structural quality of care, process quality of care and perceived quality of care. Population-staff ratio and structural quality of basic emergency obstetric care services highly influenced childbirth efficiency. Conclusions: Differences in the efficiency of service provision present an opportunity for efficiency improvement. Taking into consideration client heterogeneity, quality improvements are possible and necessary. This will stimulate utilization of ANC and childbirth services in resource-constrained health facilities. Efficiency analyses through simple techniques such as measurement of unit costs should be made standard in health care provision, health managers can then use the performance results to gauge progress and reward efficiency through performance based incentives

Leydig cell-immune cell interaction: an example of neuroendocrine-immune communication in testis

In her paper "Tilings will never be the same again" Dr Kathleen L. Wishner quoted Alvin Toffler's book Future Shock written in 1970. Toffler defined "future shock" as a time phenomenon, a product of the greatly accelerated change in society. The scientific research itself is a demonstration of this accelerated change. In particular, data systematized by Davidoff et al in this volume of Biomedical Reviews indicate the change in the understanding of the nature and origin of Leydig cells of the human testis.Biomedical Reviews 1996; 6: 1-4

Scaling properties of step bunches induced by sublimation and related mechanisms: A unified perspective

This work provides a ground for a quantitative interpretation of experiments on step bunching during sublimation of crystals with a pronounced Ehrlich-Schwoebel (ES) barrier in the regime of weak desorption. A strong step bunching instability takes place when the kinetic length is larger than the average distance between the steps on the vicinal surface. In the opposite limit the instability is weak and step bunching can occur only when the magnitude of step-step repulsion is small. The central result are power law relations of the between the width, the height, and the minimum interstep distance of a bunch. These relations are obtained from a continuum evolution equation for the surface profile, which is derived from the discrete step dynamical equations for. The analysis of the continuum equation reveals the existence of two types of stationary bunch profiles with different scaling properties. Through a mathematical equivalence on the level of the discrete step equations as well as on the continuum level, our results carry over to the problems of step bunching induced by growth with a strong inverse ES effect, and by electromigration in the attachment/detachment limited regime. Thus our work provides support for the existence of universality classes of step bunching instabilities [A. Pimpinelli et al., Phys. Rev. Lett. 88, 206103 (2002)], but some aspects of the universality scenario need to be revised.Comment: 21 pages, 8 figure

Isospin properties of electric dipole excitations in 48Ca

Two different experimental approaches were combined to study the electric dipole strength in the doubly-magic nucleus 48Ca below the neutron threshold. Real-photon scattering experiments using bremsstrahlung up to 9.9 MeV and nearly mono-energetic linearly polarized photons with energies between 6.6 and 9.51 MeV provided strength distribution and parities, and an (\alpha,\alpha'\gamma) experiment at E_{\alpha}=136 MeV gave cross sections for an isoscalar probe. The unexpected difference observed in the dipole response is compared to calculations using the first-order random-phase approximation and points to an energy-dependent isospin character. A strong isoscalar state at 7.6 MeV was identified for the first time supporting a recent theoretical prediction.Comment: 6 pages, 5 figures, as accepted in Phys. Lett.

Changes in the function of the anal sphincter complex and generated anal pressure at different anatomical levels after elastic ligature application in patients with anal fistula

Purpose: The purpose of the present study was to measure by means of especially developed apparatus the anal and intrarectal pressure before and after different operations for perianal fistulas as well as to correlate the degree of incontinence evaluated by Fecal Incontinence Severity Index (FISI) with changes in the measured pressures and type of operation used.Material and methods: The study covered 311 patients with perianal fistulas who were operated with several methods. Anal canal pressures at 5 different levels were measured by the especially developed apparatus at rest, squeezing and cough, before and after 6 months of operation. FISI form was used for incontinence detection.Results: Resting, squeezing and cough pressures were higher in men before and after operations. Average reduction of anal rest pressure by 10-15%, at contraction by 20-25% and at cough by 5-10% resulted in mild incontinence according to FISI score. Average reduction of anal rest pressure by 20-25%, at contraction by 30-40% and at cough by 20-25% correlated with postoperative moderate degree of incontinence according to FISI score. No severe incontinence was registered by FISI examination. Usage of the method of elastic ligation of perianal fistulas, i.e. the method of Hippocrates-Thoma Junescu caused the highest percentage of postoperative mild degree incontinence (15,9%) and moderate one (4,3%) by FISI. No patients presented with severe degree of incontinence.Conclusion: The method of anal sphincter tonometry demonstrated a significant reduction of anal pressure after surgery for anal fistulas. This objective decrease of anal sphincter tone correlated with the higher FISI score arguing of postoperative incontinence. The method of Hippocrates-Thoma-Junescu resulted in the highest rate of incontinence (around 20%) and anal pressure reduction

A suggestive neurotrophic potential of mast cells in heart and submandibular glands of the rat

According to the neurotrophic theory, the nerve growth factor (NGF) is widely distributed in the effector tissues of peripheral sympathetic and sensory neurons, suggesting that the density of innervation is controlled by effector derived NGF. Sympathetic neurons require access to NGF for survival throughout life, whereas sensory neurons are dependent on NGF only during restricted period of embryonic development. This development-related feature of sympathetic neurons suggests that they crucially depend on plasticity of NGF biology, including secretion, availability, and utilization, to maintain appropriate neuronal function in adult life, and even in old age. While most previous studies on the cellular source of NGF have focused on neuronal and nonneuronal effector cells, it was recently demonstrated that NGF secretion is not only restricted to cells receiving a direct innervation. Immune cells, including mast cells (MC), lymphocytes and macrophages, for example, produce and release NGF as well as NGF secretion-inducing cytokines. Likewise, since the first evidence that NGF treatment causes a significant increase in the number and size of MC has been published by Aloe and Levi-Montalcini in 1977, it has been repeatedly shown that these cells are also NGF-responsive cells, thus providing further evidence for a widely investigated MC-nerve interaction. Further on this trophobiological line, a positive correlation of the amount of NGF and expression of NGF mRNA with the density of sympathetic innervation was demonstrated in a variety of organs. In the rat heart, one such example, the atrium contains a higher amount of NGF corresponding to a denser sympathetic nerve supply compared to the ventricle. Such a correlation was also revealed in the submandibular glands (SMG) and iris. Likewise, the density of MC in the ankle joint capsule, which is heavily innervated, is greater than in the capsule of the knee, which is less densely innervated, and the MC number in the synovial joint of spontaneously hypertensive rats, which have increased sympathetic nerve supply, is significantly greater than in normotensive rats. A summing-up of the above mentioned data shows that (i) MC are NGF secreting/responsive cells and frequently colocalized with nerves, and (ii) a higher NGF amount correlates with a denser sympathetic innervation of a tissue . This, in our eyes, brings into question the sole contribution of the "classical" effector cells to neurotrophic support of sympathetic nerve-innervated tissues. Consequently, we suggest that MC, through their own and/or cytokine-induced NGF secretion, may also be implicated in the neurotrophic potential in these tissues.Biomedical Reviews 1998; 9: 143-145

Population of isomers in decay of the giant dipole resonance

The value of an isomeric ratio (IR) in N=81 isotones ($^{137}$Ba, $^{139}$Ce, $^{141}$Nd and $^{143}$Sm) is studied by means of the ($\gamma, n)$ reaction. This quantity measures a probability to populate the isomeric state in respect to the ground state population. In ($\gamma, n)$ reactions, the giant dipole resonance (GDR) is excited and after its decay by a neutron emission, the nucleus has an excitation energy of a few MeV. The forthcoming $\gamma$ decay by direct or cascade transitions deexcites the nucleus into an isomeric or ground state. It has been observed experimentally that the IR for $^{137}$Ba and $^{139}$Ce equals about 0.13 while in two heavier isotones it is even less than half the size. To explain this effect, the structure of the excited states in the energy region up to 6.5 MeV has been calculated within the Quasiparticle Phonon Model. Many states are found connected to the ground and isomeric states by $E1$, $E2$ and $M1$ transitions. The single-particle component of the wave function is responsible for the large values of the transitions. The calculated value of the isomeric ratio is in very good agreement with the experimental data for all isotones. A slightly different value of maximum energy with which the nuclei rest after neutron decay of the GDR is responsible for the reported effect of the A-dependence of the IR.Comment: 16 pages, 4 Fig