Hand arthropathy of professional origin: milkingman hand

OBJECTIVE: The aim of this case-control study was to know possible correlates between distinctive pattern of hand arthrosis and length manual milking. PATIENTS AND METHODS: Between January 1990 and January 1996, we retrospectively reviewed the patients with symptomatic arthrosis in whose hands was identified this pattern: degenerative disease of distal interphalangeal joints with radial deviation and flexion of distal phalanges in association to arthrosis involving metacarpophalangeal and interphalangeal joints of the thumb. The first 88 cases of hand arthrosis without this clinical and radiographic pattern make the control group. Patients suffering inflammatory rheumatic diseases were excluded. RESULTS: 35 patients with this special pattern of hand arthrosis were recruited. The majority of patients were women (94.3%) and coming from rural environment (94.3%). 32 patients had performed daily manual milking over a period of 20 years, but in three patients the pattern was not related to this activity (odds ratio = 928: p < 0.001). Symptoms were more frequent in the control-group (57% versus 26%; p < 0.04), in which no characteristic pattern of alignment abnormality was found. CONCLUSION: A typical pattern of hand arthrosis was associated with prolonged manual milking: degenerative disease of metacarpophalangeal and interphalangeal joints of thumb, radial deviation associated with flexion of distal phalanges of second at fourth fingers and arthrosis involving their distal interphalangeal joints, often linked to sight ulnar deviation of middle phalanges.     

Aspects of 2-acetyl-1,3-cyclopentanedione as a chromium(iii) chelating agent: nutritional implications

The chemistry of 2‐acetyl‐1,3‐cycloalkanediones has acquired increased applied importance because of the great number of applications in the agroalimentary industry. The keto‐enol ratios and equilibrium constants for proton reactions of 2‐acetyl‐1,3‐cyclopentanedione have been determined in solution using nuclear magnetic resonance and spectrophotometric methods. Chromium(iii ) is an essential nutrient and it seems that high chromium supplementation improves glucose tolerance. Chromium chelates have been shown to have a significant beneficial effect on metal status by increasing metal bioavailability in human diets. The composition and log β‐value of the complex formed in aqueous solution by chromium(iii ) with the ligand mentioned above have been determined. A detailed reaction scheme is proposed for the 1 : 1 chelation process. The kinetic data are consistent with a mechanism in which the mono‐enol tautomer of the ligand reacts with both metallic species, the fully hydrated metal ion and the Cr(OH)²⁺. The results are discussed in the light of previous work.     

Ecological parameters of arbovirus circulation on the north coast of Havana. I. Collection of culicids in the Guajaibon region

We show the culicids collected in the Guajaibón zone, in Havana Province, in order to characterize the present population according to ecological parameters and the possible risk for man. We show that Aedes scapularis is numerically and ecologically dominant over the rest of the species that attack men, as well as the possible indirect influence of culicid populations in crab caves upon human beings.     

Component behavior-based adaptation in embedded software

Several models of computation have been used in software development approaches. The specialization of the existing models makes them suitable to specific application domains. Nevertheless, when there is no solution for applications at hand, heterogeneous models have been used. Within this context, this paper discusses a heterogeneous model called extended dataflow with a focus on component-based design. The emphasis lies on the dynamics of the components, including the way they interact with each other, their behavioral modeling, and flow of control. The main objective is to provide mechanisms for supporting both the ability of the run-time environment to safely dispatch tasks and the ability of components to adapt their interfaces. This paper focuses on embedded software. The purpose of the mechanisms we have been working on is to improve robustness while promoting component-based design. An adaptive application involving digital filters is used to illustrate our approach.     

Particle deposition in random fibrous porous materials: effect of acoustic fields,fibres distribution and porosity

Porous filters are widely used to control air pollution and have different industrial applications since they constitute a reliable and low cost solution to separate particulate matter from an air stream.In this study, the particle deposition within 3D porous filters subjected to low-frequency acoustic fields is studied following a numerical approach. Findings demonstrate that the application of acoustic waves enhançes the deposition of particles, which in turn improves filter performance. It is shown that frequencies ranging from 200 to 1000 Hz (intensity 120 dB) increase particle deposition up to 2.5 times. Besides, the manner in which fibres are distributed in the porous material and the filter porosity affect considerably the number of particles deposited, for filters subjected to the same filtration velocity.     

Cure kinetics of a diglycidyl ether of bisphenol a epoxy network (n = 0) with isophorone diamine

The study of the cure reaction of a diglycidyl ether of bisphenol A epoxy network with isophorone diamine is interesting for evaluating the industrial behavior of this material. The total enthalpy of reaction, the glass‐transition temperature, and the partial enthalpies at different curing temperatures have been determined with differential scanning calorimetry in dynamic and isothermal modes. With these experimental data, the degree of conversion and the reaction rate have been obtained. A kinetic model introduces the mechanisms occurring during an epoxy chemical cure reaction. A modification of the kinetic model accounting for the influence of the diffusion of the reactive groups at high conversions is used. A thermodynamic study has allowed the calculation of the enthalpy, entropy, and Gibbs free energy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Dynamic simulation of a kinematically redundant manipulator system

A number of methods have been proposed for the control of kinematically redundant manipulators, that is, those with more than the minimum number of degrees of freedom. This article uses a dynamic simulation to test whether proposed schemes should, in fact, work well when the dynamics of the actual system are considered. In order to perform a realistic simulation, a nine-degree-of-freedom arm has been designed using commercially available motors. The simulation shows the effects that specifying a secondary goal has on the satisfaction of the primary goal. Also shown is the dependence of servo performance on modeling the load.     

Stress urinary incontinence. Our experience with its treatment using the transvaginal colposuspension technique (Raz I and II)

Presentation of our experience in the surgical treatment of urinary stress incontinence, with transvaginal colposuspension techniques, specifically those described by S. Raz and known as Raz I and Raz II. Over a 24-month period, 25 transvaginal colposuspensions (22 Raz I and 3 Raz II) were performed. The results achieved were 21 patients (84%) have recovered, while 4 (16%) remain incontinent, 3 of them referring improvement and 1 without improvement, after a follow-up of 12 to 36 months. With regard to complications, there has been 5 cases (20%) of postoperative retention, one vesical perforation while passing the needles, and a vesicle perforation during vaginal dissection of the retropubic space.     

Frustration, connectivity, and the glass transition

The concepts of connectivity, localization, and frustration are explored in relation to glass formation in amorphous materials. First, the concept of eigenclusters to geometrically characterize correlations in amorphous materials is introduced, and discussed in detail for both the Ising ferromagnet and Ising spin glass models. Second, a new, glass-forming percolation model that contains frustration as the essential ingredient, and exhibits two percolation transitions, is discussed. This new model gives new insights into frustrated systems, and applications to the Ising spin glass model and other glass-forming systems are discussed. In particular, we propose the possibility that the occurrence of a percolation-type transition at temperatures above the glass transition temperature may be a general feature of glass-forming systems. The important role of computer simulations in probing the mechanism of glass formation is emphasized.