Comparative study of the biological behaviour in hamster of two isolates of leishmania characterized respectively as L. major-like and L. donovani

Hamster inoculated intraperitoneally with 1 x 10(7) parasites of L. donovani and L. major-like of the New World were studied in groups of 15, 30, 60 and 90 days of infection. The parasite load and density showed progressive increase with the evolution of the infection and was higher in the L. donovani groups than in the L. major-like groups. The L. major-like groups showed parasite density higher in the spleen than in the liver and was similar in both organs in L. donovani groups. The histopathology showed a diffuse marked hyperplasia and hypertrophy of the reticuloendothelial system with high parasitism in the L. donovani groups while there was focal involvement of these organs in L. major-like groups, forming nodules of macrophages that were scantly parasitised. The biological behaviour could be useful in the preliminary studies of Leishmania strain in regional laboratories and understanding the histopathology of lesions caused by different leishmania species.

Estimation of rotational frequency response functions

As it is widely known, in structural dynamic applications, ranging from structural coupling to model updating, the incompatibility between measured and simulated data is inevitable, due to the problem of coordinate incompleteness. Usually, the experimental data from conventional vibration testing is collected at a few translational degrees of freedom (DOF) due to applied forces, using hammer or shaker exciters, over a limited frequency range. Hence, one can only measure a portion of the receptance matrix, few columns, related to the forced DOFs, and rows, related to the measured DOFs. In contrast, by finite element modeling, one can obtain a full data set, both in terms of DOFs and identified modes. Over the years, several model reduction techniques have been proposed, as well as data expansion ones. However, the latter are significantly fewer and the demand for efficient techniques is still an issue. In this work, one proposes a technique for expanding measured frequency response functions (FRF) over the entire set of DOFs. This technique is based upon a modified Kidder's method and the principle of reciprocity, and it avoids the need for modal identification, as it uses the measured FRFs directly. In order to illustrate the performance of the proposed technique, a set of simulated experimental translational FRFs is taken as reference to estimate rotational FRFs, including those that are due to applied moments.

Prospective study of enteropathogens in two communities of Misiones, Argentina

Children under five years of age, from two communities of different socio-economic strata (97 from Zaiman and 55 from Las Dolores) were examined epidemiologically during 2 years, by means of quarterly visits of the working team, who carried out the collection of faecal samples. During the study, one or more enteropathogens were identified in 73.9% of samples in children from Zaiman and in 58.3% of the samples from Las Dolores, being associated to diarrhoea in 70.5% and to asymptomatic infections in 65.7%. The number of diarrheic episodes was higher in Zaiman (15.45%) than in Las Dolores (12.35%), being more frequent in the spring-summer seasons. In Zaiman, the bacterial enteropathogen proportion was relevantly higher (p< 0.005) in children with diarrhoea, whereas the presence of parasites was more frequent in asymptomatic children (p< 0.01). Rotavirus had an even distribution within diarrheic and asymptomatic children. In Las Dolores, no relevant differences were found in the detection of enteroparasites between diarrheic and asymptomatic children. Mixed infections were detected; enterotoxigenic Escherichia coli (ETEC)-rotavirus and ETEC-parasites being the most frequent ones. ETEC was involved in 85% of these infections. These data, together with the high enteropathogen carriage, suggest an elevated level of environmental contamination. The latter plays an important role in diarrheic diseases, and added to the most extreme poverty, it affects children's lives.

The first two cases of Cyclospora in dogs, São Paulo, Brazil

Cyclospora cayetanensis is a coccidium which has been identified in diarrheal feces or immunocompetent individuals or in AIDS patients. The main aspects related to its epidemiology and pathogeny have not been solved so far, as well as the possibility of human infection by this protozoan being a zoonosis. We describe in this work the first case identifying the Cyclospora in dogs. Our findings, notwithstanding their preliminary characteristics, could suggest that besides untreated water, other transmission means, along with contact with dogs, there could be important factors in the human diarrhea associated with Cyclospora

Immune response and tissue cytoprotection: two sides of the same coin in immunopathology

Dissertation presented to obtain the Ph.D degree in Biochemistry

Discrete fractional order system vibrations

A theory of free vibrations of discrete fractional order (FO) systems with a finite number of degrees of freedom (dof) is developed. A FO system with a finite number of dof is defined by means of three matrices: mass inertia, system rigidity and FO elements. By adopting a matrix formulation, a mathematical description of FO discrete system free vibrations is determined in the form of coupled fractional order differential equations (FODE). The corresponding solutions in analytical form, for the special case of the matrix of FO properties elements, are determined and expressed as a polynomial series along time. For the eigen characteristic numbers, the system eigen main coordinates and the independent eigen FO modes are determined. A generalized function of visoelastic creep FO dissipation of energy and generalized forces of system with no ideal visoelastic creep FO dissipation of energy for generalized coordinates are formulated. Extended Lagrange FODE of second kind, for FO system dynamics, are also introduced. Two examples of FO chain systems are analyzed and the corresponding eigen characteristic numbers determined. It is shown that the oscillatory phenomena of a FO mechanical chain have analogies to electrical FO circuits. A FO electrical resistor is introduced and its constitutive voltage–current is formulated. Also a function of thermal energy FO dissipation of a FO electrical relation is discussed.

Simple Kinematic Design for Evading the Forced Oscillation of a Car-Wheel Suspension System

An adaptive control damping the forced vibration of a car while passing along a bumpy road is investigated. It is based on a simple kinematic description of the desired behavior of the damped system. A modified PID controller containing an approximation of Caputo’s fractional derivative suppresses the high-frequency components related to the bumps and dips, while the low frequency part of passing hills/valleys are strictly traced. Neither a complete dynamic model of the car nor ’a priori’ information on the surface of the road is needed. The adaptive control realizes this kinematic design in spite of the existence of dynamically coupled, excitable internal degrees of freedom. The method is investigated via Scicos-based simulation in the case of a paradigm. It was found that both adaptivity and fractional order derivatives are essential parts of the control that can keep the vibration of the load at bay without directly controlling its motion.

Seroprevalence of Chagas disease in schoolchildren from two municipalities of Jequitinhonha Valley, Minas Gerais, Brazil; six years following the onset of epidemiological surveillance

Six years after the beginning of the epidemiological surveillance of Chagas disease in Berilo and José Gonçalves de Minas, Jequitinhonha Valley, MG, Brazil, a serological inquiry was performed to observe whether the transmission of this endemy was occurring in this area. A randomized sample of 1,412 children seven to 14 years old, was screened. Six asymptomatic children were found to be positive, leading to 0.4% of prevalence. Hemoculture confirmed infection in five out of the six positive cases. Additional epidemiological investigation revealed important antecedents, such as disease reports in relatives and predisposing ecological and housing conditions. Our results demonstrated similar seroprevalence (0.4%) in schoolchildren, ranging from seven to 14 years old, and that were observed six years ago (0.2%) for children 0-9 year-old. Thus, considering the constant presence of Panstrogylus megistus in the peridomicile these findings emphasize the need of continuous improved epidemiological surveillance of Chagas disease in this region.

Occurrence of Proteus mirabilis associated with two species of venezuelan oysters

The fecal contamination of raw seafood by indicators and opportunistic pathogenic microorganisms represents a public health concern. The objective of this study was to investigate the presence of enteric bacteria colonizing oysters collected from a Venezuelan touristic area. Oyster samples were collected at the northwestern coast of Venezuela and local salinity, pH, temperature, and dissolved oxygen of seawater were recorded. Total and fecal coliforms were measured for the assessment of the microbiological quality of water and oysters, using the Multiple Tube Fermentation technique. Analyses were made using cultures and 16S rRNA gene sequencing. Diverse enrichment and selective culture methods were used to isolate enteric bacteria. We obtained pure cultures of Gram-negative straight rods with fimbriae from Isognomon alatus and Crassostrea rhizophorae. Our results show that P. mirabilis was predominant under our culture conditions. We confirmed the identity of the cultures by biochemical tests, 16S rRNA gene sequencing, and data analysis. Other enterobacteria such as Escherichia coli, Morganella morganii and Klebsiella pneumoniae were also isolated from seawater and oysters. The presence of pathogenic bacteria in oysters could have serious epidemiological implications and a potential human health risk associated with consumption of raw seafood.

In Situ Breakage of Implanon® - Two Cases of a Rare Occurrence

BACKGROUND: In situ breakage of Implanon® is a rare occurrence with unknown clinical significance. Authors report two different cases of broken Implanon® of women attended at our Family Planning Clinic. DISCUSSION: In situ implants may spontaneously and asymptomatically break, although some uncertainty relies on whether that situation has a real impact on the contraceptive effectiveness or on bleeding patterns. Even more, it can be argued if, as a result of an occurrence of that nature, the implant shall or shall not be removed before the envisaged 3-year period of effectiveness. CONCLUSION: Currently, the clinical significance of implant breakage remains unknown. The decision to remove a broken or bent implant should be based on clinical judgements considering patients' wishes.

Adjusting to external imbalances within the EMU, the case of Portugal

From 1995 to 2010 Portugal has accumulated a negative international asset position of 110 percent of GDP. In a developed and aging economy the number is astonishing and any argument to consider it sustainable must rely on extremely favorable forecasts on growth. Portuguese policy options are reduced in number: no autonomous monetary policy, no currency to devaluate, and limited discretion in changing fiscal deficits and government debt. To start the necessary deleveraging a remaining possible policy is a budget-neutral change of the tax structure that increases private saving and net exports. An increase in the VAT and a decrease in the employer’s social security contribution tax can achieve the desired outcome in the short run if they are complemented with wage moderation. To obtain a substantial improvement in competitiveness and a large decrease in consumption, the changes in the tax rates have to be large. While a precise quantitative assessment is difficult, the initial increase in the effective VAT rate needed to allow the social security tax to decrease by 16 percentage points (pp) is approximately 10 pp. Such a large increase in the effective VAT rate could be obtained by raising most of the reduced VAT rates to the new general VAT rate of 23 percent. The empirical analysis shows that over time the suggested tax swap could generate surpluses and improve the trade balance. A temporary version of the suggested tax-swap has the attractiveness to achieve a sharper increase in the private saving rate maintaining the short run gains in competitiveness. Finally, the temporary version of the fiscal devaluation could be the basis for an automatic stabilizer to external imbalances within a monetary union.Portugal has been running large current account deficits every year since 1995. These deficits have accumulated to an astonishing 110 percent of GDP negative external asset position. The sustainability of such a large external position is questionable and must rely on fantastic productivity growth expectations. The recent global financial crisis appears to have anticipated the international investors reality check on those future expectations with the result of a large increase in the cost of external financing. Today the rebalancing of the current account through an increase in national savings and an improvement in competitiveness must be at the top of the Portuguese authorities “to do” list as the cost of a pull out from international investors is of the order of 10% of GDP. The external rebalancing is difficult as the degrees of freedom of the Portuguese authorities are limited in number: they have no autonomous monetary policy, no currency to devaluate, and little discretion in fiscal policy as deficit limits and debt targets are set by the Stability Growth Pact and the postcrisis consensus on medium-term fiscal consolidation. One possibility that remains is to change the fiscal policy mix for a given budget deficit. The purpose of this paper is to explore the effects of a “fiscal devaluation”1 obtained through a tax swap between employers’ social security contributions and taxes on consumption2. The paper begins by illustrating Portugal’s current account evolution during the euro period. The second section section lays out a model to offer a qualitative assessment of the dynamic outcomes of the the tax swap. I show that the suggested tax swap can in theory achieve the desired outcomes in terms of competitiveness and consumption if complemented with moderation (stickiness) in wages. I also study the effects of a temporary version of the tax swap and show that it achieves a sharper improvement in the current account that accelerate the rebalancing. The third section moves to the empirical analysis and estimates the likely effects of the tax swap for the Portuguese economy. The fourth section concludes.

Electrodialytic remediation of two types of air pollution control residues and their applicability in construction materials

Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente Perfil de Engenharia de Sistemas Ambientais

Effect of feeding frequency on the reproductive efficiency of two species of Triatoma with different epidemiological importance

Introduction In Triatominae, reproductive efficiency is an important factor influencing population dynamics, and a useful parameter in measuring a species' epidemiological significance as a vector of Trypanosoma cruzi (Chagas, 1909). The reproductive efficiency of triatomines is affected by food availability; hence, we measured and compared the effects of feeding frequency on the reproductive parameters of Triatoma patagonica (Del Ponte, 1929) and Triatoma infestans (Klug, 1934), and the effects of starvation on T. patagonica. Methods Couples from both species were fed weekly, or every 3 weeks; in addition, females in couples of T. patagonica were not fed. Each couple was observed weekly and reproductive efficiency was assessed on the following parameters: fecundity (eggs/female), fertility (eggs hatched/eggs laid), initiation and end of oviposition, initiation of mating, number of matings/week, and number of reproductive weeks. Relative meal size index (RMS), blood consumption index (CI), and E values (eggs/mg blood) were also calculated. Results Changes in feeding frequency affected the reproductive parameters of T. patagonica only, with a decrease in fecundity and number of reproductive weeks for those fed every 3 weeks, or not fed. The reproductive period, RMS index, and CI were lower for T. patagonica than T. infestans. However, despite the lower fecundity of T. patagonica, this species required less blood to produce eggs, with an E values of 2 compared to 2.94 for T. infestans. Conclusions Our results suggest that the differences in fecundity observed between species reflect the availability of food in their natural ecotopes.

Two decades of tuberculosis in a city in Northeastern Brazil: advances and challenges in time and space

Abstract: INTRODUCTION This study presents two decades of epidemiological data on tuberculosis (TB), in order to understanding the disease profile and its spatiotemporal dynamics. METHODS This descriptive study was performed in the City of Olinda/Pernambuco, Brazil, from 1991-2010, and it analyzed new patients with TB living in the city. We used the χ²-test with a p-value <0.05 to identify differences in trends. Incidence and cluster distribution were identified using spatial scan statistics. RESULTS In total, 6202 new cases were recorded during the two decades. The highest incidence occurred in 1995 (110 cases/100,000 inhabitants), and the lowest occurred in 2009 (65 cases/100,000 inhabitants) (β=-1.44; R²=0.43; p=0.0018). The highest mortality occurred in 1998 (16 deaths/100,000 inhabitants), and the lowest occurred in 2008 (5 deaths/100,000 inhabitants) (β=-0.19; R²=0.17; p=0.07). There was a male predominance (65%), and ages ranged from 20-49 years (65%). There was a substantial increase in the number of patients that were cured after treatment (60% to 67%; p<0.001) as well as those tested for HIV (1.9% to 58.5%; p<0.001). During the first decade, clusters with p-values <0.05 included 29% of the total notified cases, and in the second decade, that percentage was 12%. CONCLUSIONS We observed a decreasing trend in incidence, which was significant, and mortality rates, which was not significant. The increased number of laboratory tests performed reflects advances in surveillance, and a reduction in the proportion of cases in primary clusters suggests, among other things, that the disease is spreading across the region.