Diabetes mellitus and periodontal disease in Malta

Diabetes mellitus is of some importance in dentistry. Its possible role in the etiology of periodontal disease is still under investigation. Lowered tissue resistance to trauma or infection make this type of patient a possible hazard when undertaking oral surgery under local anesthesia. In view of the high incidence of diabetes in Malta, a study of patients attending the Diabetic Clinic, St. Luke's Hospital Malta has been in progress since 1964. The objects of this study had been to ascertain the role of the disease in conditions of the mouth and in the incidence of complications following oral surgical procedures and their prevention. This particular report is restricted to diabetes and periodontal disease. No relationship was shown to exist between duration of diabetes and obesity, as compared with periodontal disease. The periodontal disease in patients under insulin therapy was more severe than in those receiving oral hypoglycemic drugs and least severe in those under dietary control only. Patients with higher levels of fasting or two-hour blood sugar showed a more severe periodontal condition. Patients with a higher incidence of general diabetic complications also manifested higher periodontal disease incidence levels. No relationship between the incidence of "dry socket" following tooth extraction and fasting blood sugar levels could be demonstrated.peer-reviewe

Renormalization-group at criticality and complete analyticity of constrained models: a numerical study

We study the majority rule transformation applied to the Gibbs measure for the 2--D Ising model at the critical point. The aim is to show that the renormalized hamiltonian is well defined in the sense that the renormalized measure is Gibbsian. We analyze the validity of Dobrushin-Shlosman Uniqueness (DSU) finite-size condition for the "constrained models" corresponding to different configurations of the "image" system. It is known that DSU implies, in our 2--D case, complete analyticity from which, as it has been recently shown by Haller and Kennedy, Gibbsianness follows. We introduce a Monte Carlo algorithm to compute an upper bound to Vasserstein distance (appearing in DSU) between finite volume Gibbs measures with different boundary conditions. We get strong numerical evidence that indeed DSU condition is verified for a large enough volume $V$ for all constrained models.Comment: 39 pages, teX file, 4 Postscript figures, 1 TeX figur

The Change of Job Opportunities: the Role of Computerization and Institutions

This paper studies the pattern of job opportunities over the last two decades in European countries. We find that the share of high-skilled jobs have been expanding over time, while the share of medium- skilled jobs have been declining. These changes are in line with the US patterns and, according to the previous literature, they come from recent technological changes. However, our data show an interesting difference between the US and Europe: in Europe there is not any increase in the share of low-skilled employment. Moreover, we find that the difference between the proportion of employment hired in low-skilled and medium-skilled jobs is negatively correlated with both the unemployment rate and the degree of employment protection in the labour market. We propose a theoretical model to study the effects of a technological shock on the employment structure in a unionized economy. By accounting for the collective bargaining process, our model may fit Continental Europe better than the previous ones. We conclude that the definition of the union policy is crucial in order to explain observed cross-country heterogeneity in low-skilled employment.

Magnetic Schr\"odinger Operators as the Quasi-Classical Limit of Pauli-Fierz-type Models

We study the quasi-classical limit of the Pauli-Fierz model: the system is composed of finitely many non-relativistic charged particles interacting with a bosonic radiation field. We trace out the degrees of freedom of the field, and consider the classical limit of the latter. We prove that the partial trace of the full Hamiltonian converges, in resolvent sense, to an effective Schr\"odinger operator with magnetic field and a corrective electric potential that depends on the field configuration. Furthermore, we prove the convergence of the ground state energy of the microscopic system to the infimum over all possible classical field configurations of the ground state energy of the effective Schr\"odinger operator.Comment: 26 pages, pdfLatex. Final version to appear in J. Spectr. Theor

Yield-driven power-delay-optimal CMOS full-adder design complying with automotive product specifications of PVT variations and NBTI degradations

We present the detailed results of the application of mathematical optimization algorithms to transistor sizing in a full-adder cell design, to obtain the maximum expected fabrication yield. The approach takes into account all the fabrication process parameter variations specified in an industrial PDK, in addition to operating condition range and NBTI aging. The final design solutions present transistor sizing, which depart from intuitive transistor sizing criteria and show dramatic yield improvements, which have been verified by Monte Carlo SPICE analysis

Narrowband delay tolerant protocols for WSN applications. Characterization and selection guide

This article focuses on delay tolerant protocols for Wireless Sensor Network (WSN) applications, considering both established and new protocols. We obtained a comparison of their characteristics by implementing all of them on an original platform for network simulation, and by testing their behavior on a common test-bench. Thereafter, matching the requirements linked to each application with the performances achieved in the test-bench, allowed us to define an application oriented protocol selection guide

Computing Strong and Weak Permissions in Defeasible Logic

In this paper we propose an extension of Defeasible Logic to represent and compute three concepts of defeasible permission. In particular, we discuss different types of explicit permissive norms that work as exceptions to opposite obligations. Moreover, we show how strong permissions can be represented both with, and without introducing a new consequence relation for inferring conclusions from explicit permissive norms. Finally, we illustrate how a preference operator applicable to contrary-to-duty obligations can be combined with a new operator representing ordered sequences of strong permissions which derogate from prohibitions. The logical system is studied from a computational standpoint and is shown to have liner computational complexity

Passive control of a falling sphere by elliptic-shaped appendages

The majority of investigations characterizing the motion of single or multiple particles in fluid flows consider canonical body shapes, such as spheres, cylinders, discs, etc. However, protrusions on bodies -- being either as surface imperfections or appendages that serve a function -- are ubiquitous in both nature and applications. In this work, we characterize how the dynamics of a sphere with an axis-symmetric wake is modified in the presence of thin three-dimensional elliptic-shaped protrusions. By investigating a wide range of three-dimensional appendages with different aspect ratios and lengths, we clearly show that the sphere with an appendage may robustly undergo an inverted-pendulum-like (IPL) instability. This means that the position of the appendage placed behind the sphere and aligned with the free-stream direction is unstable, in a similar way that an inverted pendulum is unstable under gravity. Due to this instability, non-trivial forces are generated on the body, leading to turn and drift, if the body is free to fall under gravity. Moreover, we identify the aspect ratio and length of the appendage that induces the largest side force on the sphere, and therefore also the largest drift for a freely falling body. Finally, we explain the physical mechanisms behind these observations in the context of the IPL instability, i.e., the balance between surface area of the appendage exposed to reversed flow in the wake and the surface area of the appendage exposed to fast free-stream flow.Comment: 16 pages, 13 figures, 2 tables, under consideration for publication in Phys. Rev. Fluids; revisio