An evaluation into the potential of biological processing for the removal of metals from sewage sludges

The use of sewage sludge in agricultural land as a means of sludge disposal and recycling has been shown to be economical and suitable because of the presence of nutrients such as nitrogen and phosphorus. However, municipal sludges often contain high quantities of toxic metals and other compounds that must be removed for its safe use in agricultural soils. The biological leaching of metals from sewage sludges has been shown to be a promising technique for metal detoxifying in such complex matrix. The process efficiency is dependent on several physico-chemical parameters, such as total solids concentration, metal forms, pH-ORP, and temperature. Scale-up of the process has not yet been defined and is still pursuing the correct operational design. Current research involving the bioleaching of metals from sewage sludge and its application to land, which affects soil physical properties, are presented and discussed.

Dog culling and replacement in an area endemic for visceral leishmaniasis in Brazil

Measures employed to control visceral leishmaniasis in Brazil have focused on vector control by residual insecticide spraying and diagnosis of infection with elimination of positive dogs. We describe dog culling and replacement in a Brazilian endemic area (the Alvorada District, Aracatuba, SP) in order to better understand dog population dynamics when elimination of the dog reservoir is adopted as the main control measure. From August 2002 to July 2004, 60.9% of the estimated dog population for the area was culled with a mean age of 34 months old. The presence of anti-Leishmania sp. antibodies was recorded for only 26.7% of the euthanized canines. Replacement was observed in 38.8% of the cases, some of them by 2 or more dogs and in a mean time of 4 months. Dogs were replaced mostly by puppies of both sexes with a mean age of 6.8 months. From August 2002 to April 2005 we were able to follow-up 116 of these dogs, during a mean time of 8.7 months. Canine visceral leishmaniasis seropositivity by ELISA was observed in 42.2% of the followed dogs, 30.6% of which were already positive at the first evaluation. By the end of the follow-up period 37% of the dogs were submitted to euthanasia, with a mean age of 18.3 months. In the studied CVL endemic area of Brazil, euthanasia and the subsequent replacement ratio were high, increasing the dog population turnover and leading to a younger population that might be more susceptible to a variety of other infectious diseases in addition to CVL. Dog culling as a control strategy for VL should be reassessed. (C) 2008 Elsevier B.V. All rights reserved.

The use of shallow seismic reflection technique in near surface exploration of urban sites: An evaluation in the city of SãO Paulo, Brazil

In order to evaluate the use of shallow seismic technique to delineate geological and geotechnical features up to 40 meters depth in noisy urban areas covered with asphalt pavement, five survey lines were conducted in the metropolitan area of São Paulo City. The data were acquired using a 24-bit, 24-channel seismograph, 30 and 100 Hz geophones and a sledgehammer-plate system as seismic source. Seismic reflection data were recorded using a CMP (common mid point) acquisition method. The processing routine consisted of: prestack band-pass filtering (90-250 Hz); automatic gain control (AGC); muting (digital zeroin) of dead/noisy traces, ground roll, air-wave and refracted-wave; CMP sorting; velocity analyses; normal move-out corrections; residual static corrections; f-k filtering; CMP stacking. The near surface is geologically characterized by unconsolidated fill materials and Quaternary sediments with organic material overlying Tertiary sediments with the water table 2 to 5 m below the surface. The basement is composed of granite and gneiss. Reflections were observed from 40 milliseconds to 65 ms two-way traveltime and were related to the silt clay layer and fine sand layer contact of the Tertiary sediments and to the weathered basement. The CMP seismic-reflection technique has been shown to be useful for mapping the sedimentary layers and the bedrock of the São Paulo sedimentary basin for the purposes of shallow investigations related to engineering problems. In spite of the strong cultural noise observed in these urban areas and problems with planting geophones we verified that, with the proper equipment, field parameters and particularly great care in data collection and processing, we can overcome the adverse field conditions and to image reflections from layers as shallow as 20 meters.

An evaluation of the productivity of mischocyttarus drewseni in a semi-urban environment (Hymenoptera: Polistinae)

The biology and productivity of Myschocytarus drewseni were studied in semi urban conditions at Rio Claro, S P - Brazil. We observed 51 nest foundations, of which 24 (47%) were destroyed or predated, 13 (25.5 %) were abandoned and 14 (27.5%) completed the cycle. The life-span of colonies ranged from 44-427 days with a mean of 216.7 ± 140.6 days, producing 8-390 cells with a mean of 125.7 ± 137.9 cells, and 2-303 adults with a mean of 89.4 ± 110.36 adults. We observed a maximum of 3 utilizations/cell. This showed that the species presents asynchronous foundation and abandoningoccurs throughout the year. Also, the chance of a colony utilizing the same cells two or three times for adult production is highly dependent on the colony size/age, and the relation between them is positive, meaning that there is a greater chance of cell re-utilization in larger/older colonies.

The impact of structural reforms on growth in Latin America and the Caribbean: an empirical estimation

Includes bibliography

Free trade agreements in Latin America since 1990: an evaluation of export diversification

Includes bibliography

Highway Concessions: An Evaluation Methodology

The Transport Unit has developed a project evaluation methodology whereby benefits may be broken down by target groups. To date, this approach has been used in three highway concession projects in Argentina, Chile and Colombia. It is also applicable to other projects where it is important to know how benefits are to be distributed as well as what the overall benefits will be. For general inquiries and information on this methodology, please contact ithomson@eclac.cl.

Construction and validation of an instrument to assess the reading comprehension of students from the third to the fifth grades of elementary school

Objetivo:Este estudo teve como objetivo construir e validar um instrumento de avaliação da compreensão de leitura a fim de caracterizar o perfil de leitura e detectar dificuldades de compreensão em escolares do terceiro ao quinto ano do Ensino Fundamental.Métodos:Participaram 378 escolares divididos em trés grupos para avaliação da compreensão de proposições literais e inferenciais de micro e macroestruturas de dois textos expositivos e dois textos narrativos por meio de questões de múltipla escolha.Resultados:Os dados analisados estatisticamente indicaram valores do teste alfa de Cronbach apresentando consisténcia interna nos quatros textos aplicados para os trés grupos.Conclusão:Foi possível constatar que os escolares apresentaram menor número de erros com o aumento da escolarização e que cada tipo de texto apresentou uma dificuldade específica para os escolares.

Effect of cleansing methods on saliva-contaminated zirconia: an evaluation of resin bond durability

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

An Evaluation of Diazacon as a Potential Contraceptive in Non-Native Rose-Ringed Parakeets

Rose-ringed parakeets (Psittacula krameri) have become widely established outside their native range through accidental or deliberate release. Potential economic impacts on agriculture, conservation concerns, and mixed public opinion regarding the species have highlighted the need to develop effective but humane management options. Fertility control might provide such a solution if a safe and environmentally benign contraceptive was available. The chemical 20,25-diazacholesterol dihydrochloride (diazacon) has previously been used to reduce reproductive output in avian species through reduction of blood cholesterol and cholesterol-dependent reproductive hormones. We orally dosed captive rose-ringed parakeets with a solution of either 9 mg/kg or 18 mg/kg of diazacon for up to 10 days and found that a dose of 18 mg/kg for 10 days temporarily reduced blood cholesterol levels with no adverse side effects. We evaluated this dose level in a captive population in semi-natural conditions during the 2008 breeding season and found a significant decrease in fertility. We concluded that diazacon has potential for fertility control in this species if a suitable formulation and delivery system is developed for free-living populations.

Hypotheses, rationale, design, and methods for prognostic evaluation of cardiac biomarker elevation after percutaneous and surgical revascularization in the absence of manifest myocardial infarction. A comparative analysis of biomarkers and cardiac magnetic resonance. The MASS-V Trial

Background: Although the release of cardiac biomarkers after percutaneous (PCI) or surgical revascularization (CABG) is common, its prognostic significance is not known. Questions remain about the mechanisms and degree of correlation between the release, the volume of myocardial tissue loss, and the long-term significance. Delayed-enhancement of cardiac magnetic resonance (CMR) consistently quantifies areas of irreversible myocardial injury. To investigate the quantitative relationship between irreversible injury and cardiac biomarkers, we will evaluate the extent of irreversible injury in patients undergoing PCI and CABG and relate it to postprocedural modifications in cardiac biomarkers and long-term prognosis. Methods/Design: The study will include 150 patients with multivessel coronary artery disease (CAD) with left ventricle ejection fraction (LVEF) and a formal indication for CABG; 50 patients will undergo CABG with cardiopulmonary bypass (CPB); 50 patients with the same arterial and ventricular condition indicated for myocardial revascularization will undergo CABG without CPB; and another 50 patients with CAD and preserved ventricular function will undergo PCI using stents. All patients will undergo CMR before and after surgery or PCI. We will also evaluate the release of cardiac markers of necrosis immediately before and after each procedure. Primary outcome considered is overall death in a 5-year follow-up. Secondary outcomes are levels of CK-MB isoenzyme and I-Troponin in association with presence of myocardial fibrosis and systolic left ventricle dysfunction assessed by CMR. Discussion: The MASS-V Trial aims to establish reliable values for parameters of enzyme markers of myocardial necrosis in the absence of manifest myocardial infarction after mechanical interventions. The establishments of these indices have diagnostic value and clinical prognosis and therefore require relevant and different therapeutic measures. In daily practice, the inappropriate use of these necrosis markers has led to misdiagnosis and therefore wrong treatment. The appearance of a more sensitive tool such as CMR provides an unprecedented diagnostic accuracy of myocardial damage when correlated with necrosis enzyme markers. We aim to correlate laboratory data with imaging, thereby establishing more refined data on the presence or absence of irreversible myocardial injury after the procedure, either percutaneous or surgical, and this, with or without the use of cardiopulmonary bypass.

An evaluation of dosimetric characteristics of MAGIC gel modified by adding formaldehyde (MAGIC-f)

Purpose: To evaluate the dosimetric characteristics of a new formulation of MAGIC gel, called MAGIC-f, which contains the addition of 3.3% formaldehyde, resulting in a gel with increased thermal stability. Methods: MAGIC-f gel was prepared and stored in hermetically sealed plastic containers. After irradiation, magnetic resonance images (MRI) were acquired to evaluate dose and dose distribution. Dosimetric characterization was performed by means of depth dose measurements, dose response sensitivity and linearity, temporal stability, energy and dose rate dependence, dose integration using sequential beams, temperature influence during MRI acquisition and dose distribution integrity. Results: MAGIC-f depth dose measurements are compatible with the dosimetric table data within +/- 4% uncertainty. The dosimeter's R-2 response varies linearly with dose at least from 0 to 6 Gy. The time-course of the sensitivity of the dosimeter following irradiation, indicated stabilization after 2 weeks. The dosimeter's response to irradiation was altered by 6% when increasing the energy from cobalt beams to 10 MV beams. The dose rate dependence of this new formulation of gel dosimeter is small: less than 2.5% for a variation from 200 to 500 cGy/min, and the dependence with the fractionation scheme is about 50% smaller than for standard MAGIC gel, The dependence on scanning temperature was also verified, and the integrity of the dose distribution was confirmed for a period of 90 days. Conclusions: The results demonstrate the applicability of this new dosimeter in tridimensional dose distribution measurements. (C) 2012 Elsevier Ltd. All rights reserved.

Secondary production of sandy beach macrofauna: An evaluation of predictive models

During the last three decades, several predictive models have been developed to estimate the somatic production of macroinvertebrates. Although the models have been evaluated for their ability to assess the production of macrobenthos in different marine ecosystems, these approaches have not been applied specifically to sandy beach macrofauna and may not be directly applicable to this transitional environment. Hence, in this study, a broad literature review of sandy beach macrofauna production was conducted and estimates obtained with cohort-based and size-based methods were collected. The performance of nine models in estimating the production of individual populations from the sandy beach environment, evaluated for all taxonomic groups combined and for individual groups separately, was assessed, comparing the production predicted by the models to the estimates obtained from the literature (observed production). Most of the models overestimated population production compared to observed production estimates, whether for all populations combined or more specific taxonomic groups. However, estimates by two models developed by Cusson and Bourget provided best fits to measured production, and thus represent the best alternatives to the cohort-based and size-based methods in this habitat. The consistent performance of one of these Cusson and Bourget models, which was developed for the macrobenthos of sandy substrate habitats (C&B-SS), shows that the performance of a model does not depend on whether it was developed for a specific taxonomic group. Moreover, since some widely used models (e.g., the Robertson model) show very different responses when applied to the macrofauna of different marine environments (e.g., sandy beaches and estuaries), prior evaluation of these models is essential.

Comparative study of beta-carotene and microencapsulated beta-carotene: Evaluation of their genotoxic and antigenotoxic effects

beta-Carotene (BC) is one of the natural pigments that is most commonly added to food; however, the utilization of BC is limited due to its instability. Microencapsulation techniques are commonly used because they can protect the microencapsulated material from oxidization. Nevertheless, the properties of the encapsulated compounds must be studied. We compared the antigenotoxic potential of pure and microencapsulated beta-carotene (mBC) in Wistar rats. Two doses of BC or mBC (2.5 or 5.0 mg/kg) were administered by gavage over a period of 14 days. The final gavage was followed by an injection of doxorubicin (DXR). After 24 h the animals were euthanized. The micronucleus test results showed that when both mBC and DXR were given, only the higher dose was antigenotoxic. The results of the comet assay show that when given in association with DXR, mBC had protective effects in the liver. The differences between the results obtained with BC and mBC suggest that possibly the carotenoid biodisponibility was modified by the process of microencapsulation. In conclusion, mBC does not lose its protective properties, but higher doses must be used to observe antigenotoxic effects. This is the first time that the genotoxicity and antigenotoxicity of a microencapsulated compound was evaluated in vivo. (C) 2012 Elsevier Ltd. All rights reserved.

Congenital Nystagmus eye movements analysis and oculomotor system models evaluation

The term Congenital Nystagmus (Early Onset Nystagmus or Infantile Nystagmus Syndrome) refers to a pathology characterised by an involuntary movement of the eyes, which often seriously reduces a subject’s vision. Congenital Nystagmus (CN) is a specific kind of nystagmus within the wider classification of infantile nystagmus, which can be best recognized and classified by means of a combination of clinical investigations and motility analysis; in some cases, eye movement recording and analysis are indispensable for diagnosis. However, interpretation of eye movement recordings still lacks of complete reliability; hence new analysis techniques and precise identification of concise parameters directly related to visual acuity are necessary to further support physicians’ decisions. To this aim, an index computed from eye movement recordings and related to the visual acuity of a subject is proposed in this thesis. This estimator is based on two parameters: the time spent by a subject effectively viewing a target (foveation time - Tf) and the standard deviation of eye position (SDp). Moreover, since previous studies have shown that visual acuity largely depends on SDp, a data collection pilot study was also conducted with the purpose of specifically identifying eventual slow rhythmic component in the eye position and to characterise in more detail the SDp. The results are presented in this thesis. In addition, some oculomotor system models are reviewed and a new approach to those models, i.e. the recovery of periodic orbits of the oculomotor system in patients with CN, is tested on real patients data. In conclusion, the results obtained within this research consent to completely and reliably characterise the slow rhythmic component sometimes present in eye position recordings of CN subjects and to better classify the different kinds of CN waveforms. Those findings can successfully support the clinicians in therapy planning and treatment outcome evaluation.