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The photoelectric properties of multilayer organic photovoltaic cells (OPV cells) were studied. The active organic layers consisted of a planar heterojunction between a layer of Meso-Tetrakis(4-BromoPhenyl) Zinc(II) Porphyrin (BrPhPZn) as electron donor (ED) and a layer fullerene molecules. The devices were fabricated in a high vacuum by thermal sublimation, a technique that allows multilayer devices realization easily by successive depositions, and it does not require solvents, achieving purer films with reproducible characteristics. Taking into account that the anodic contact, a key factor for cell efficiency, is favored by the inclusion of a thin anodic buffer layer (ABL), the effect on the yield after including one or two (ABL): MoO3 or MoO3-CuI layers was studied. The cell which has the best photovoltaic characteristics has a BrPhPZn (ED) thickness of only 12.5 nm. This small thickness is related with the low conductivity of this organic molecule. On the other hand, including a thin MoO3-CuI bilayer increased, such device’s efficiency in a 200%, with regard to a cell without ABL, getting for one cell ITO/MoO3-CuI/BrPhPZn/C60/Alq3/Al, with a 1.03% yield.

In this work it was carried out the bioremediation of water containing chlorides with native microalgae (MCA) provided by the Centre for study and research in biotechnology (CIBIOT) at Universidad Pontificia Bolivariana. Microalgae presented an adaptation to the water and so the conditions evaluated reaching a production of CO2 in mg L-1 of 53.0, 26.6, 56.0, 16.0 and 30.0 and chloride removal efficiencies of 16.37, 26.03, 40.04, 25.96 and 20.25% for microalgae1, microalgae2, microalgae3, microalgae4 and microalgae5 respectively. Water bioremediation process was carried out with content of chlorides in fed batch system with an initial concentration of chlorides of 20585 mg L-1 every 2 days. The Manipulated variables were: the flow of MCA3 (10% inoculum) for test one; NPK flow for test two, and flow of flow of MCA3+0.5 g L-1 NPK. Chloride removal efficiencies were 66.88%, 63.41% and 66.98% for test one, two and three respectively, for a total bioprocess time of 55 days. Resumo Neste trabalho avaliou-se a biorremediação da água com conteúdos de cloretos utilizando microalgas nativas (MCA) fornecidas pelo Centro de Estudos e Pesquisas em Biotecnologia (CIBIOT) da Universidad Pontifícia Bolivariana. As microalgas empregadas apresentaram uma adaptação ao meio de cultura e as condições operacionais avaliadas atingindo uma produção de CO2 em mg L-1 de 53,0, 26,6, 56,0, 16,0 e 30,0 e eficiências de remoção de cloretos de 16,37, 26,03, 40,04, 25,96 e 20,25% para MCA1, MCA2, MCA3, MCA4 e MCA5 respectivamente. A biorremediação da água com conteúdos de cloretos foi realizada em modo batelada alimentada (Feed Batch) com uma concentração inicial de cloretos de 20585 mg L-1. A alimentação foi realizada a cada 2 dias. A variável manipulada foi: ensaio um, uma vazão de MCA3 (10% de inoculo); ensaio dois, uma vazão de NPK e ensaio três, uma vazão de MCA3+0,5 g L-1 NPK. As eficiências de remoção foram 66,88%, 63,41% e 66,98% para os ensaios um, dois e três, respectivamente num tempo do bioprocesso total de 55 dias.

3Beta,11beta-dihydroxy-9alpha-fluor-5alpha-androstane-17-one (2), 3beta-acetoxy-9alpha-fluor-11beta-hydroxy-5alpha-androstane-17-one (3), 3beta-acetoxy-9alpha-fluor-11beta,17beta-dihydroxy-5alpha-androstane (4), 3beta,17beta-diacetoxy-9alpha-fluor-11beta-hydroxy-5alpha-androstane (5), 3beta-acetoxy-9alpha-fluor-11beta-hydroxy-5alpha-androstane 17beta-propionate (6), 3beta-acetoxy-9alpha-fluor-11beta-hydroxy-5alpha-androstane 17beta-enanthate (7), 3beta-acetoxy-9alpha-fluor-11beta-hydroxy-5alpha-androstane 17beta-isobutyrate (8) were synthesized in the present study. Compounds 2 and 8 exhibited higher anabolic activity than the rest of the synthesized compounds. The structure of all these newly synthesized compounds was confirmed by analytic spectral data (mass, (1)H NMR and (13)C NMR).

Poly(3,5‐dichloroaniline) was prepared by chemical oxidation in the presence of various sulfonic acids as doping agent, using potassium permanganate as oxidant. 1‐Naphtalene sulfonic acid, 2‐naphatalene sulphonic acid, 1,5‐naphtalene disulfonic acid, and p‐toluenesulfonic acid were the acids of choice. Infrared and UV‐Vis spectroscopy, utilized to characterize the polymers, revealed that the compounds exist in the emeraldine (conductive) oxidation state. The level of doping, conductivity, and morphology were determined as well. The presence of a sulfonic acid produces a morphological change, from granular to microtubule structures, which is responsible for the strong increase in the conductivity of the polymer.

Thiophene structures anchored in position 3 of the ring were synthesized using spacers of different lengths (6,8,10, and 12 carbon atoms linked to a 2-((4-octylphenylimino)methyl)phenol) group. The thermal studies of the units demonstrated that they possess liquid-crystal properties and their optical study indicated that all the compounds present a nematic phase. Further chemical polymerization of these units was performed by oxidation of the respective monomers using iron(III) chloride. The resulting polymers proved to be insoluble and therefore their characterization was only possible by XPS and FT-IR techniques. In addition, as the polymers have no melting point because they decompose at temperatures over 200 °C, it was not possible to determine if they were effectively liquid-crystals. Finally, the iodine-doped polymers displayed conductivities of about 10-7 S cm-1, i.e., semiconductor-like conductivity.

A list of species and a photographic catalog of moths of the family Sphingidae reported for Colombia is presented. Following examination of 1463 specimens deposited in major entomological collections of Colombia, and a review of the literature, 188 species are reported for the country, of which 19 species and Phryxus genus are reported for the first time for Colombia. The genus Xylophanes has the most species recorded and also the most geographical records. The Andean region has the highest number of records. A diagnosis of each subfamily and genus, comments on the biology of many of the reported species and dichotomous keys are also presented.

Young red tilapias were exposed for 96 h to each one of 6 concentrations of the pesticide Diazinon in order to determine the pesticide's acute toxicity level. After the ascertaining the lethal concentration (LC50) at 96 h, a level 10 times lower was selected for the bioaccumulation study of the pesticide in male and female specimens exposed for 9 days. The elimination process was carried out for 10 days beginning right after the conclusion of the accumulation process. Analytical procedures were developed and used for the studies of acute toxicity and bioaccumulation of Diazinon in red tilapia. A lethal concentration [LC50 (96 h)] of 3.85 mg/L was found, and steady-state accumulation, at a concentration of 28.45 mg/kg, was reached at 7.72 days. In the elimination process a concentration of 0.29 mg/kg was found in tilapia tissue by the sixth day after the fish were moved to clean water, and it continued to decrease quickly toward nondetectable levels.

Like all the major upwelling regions, the Canary Current is characterised by intense mesoscale structure in the transition zone between the cool, nutrient-rich waters of the coastal upwelling regime and the warmer, oligotrophic waters of the open ocean. The Canary Island archipelago, which straddles the transition, introduces a second source of variability by perturbing the general southwestward flow of both ocean currents and Trade winds. The combined effects of the flow disturbance and the eddying and meandering of the boundary between upwelled and oceanic waters produce a complex pattern of regional variability. On the basis of historical data and a series of interdisciplinary field studies, the principal features of the region are described. These include a prominent upwelling filament originating near 28°N off the African coast, cyclonic and anti-cyclonic eddies downstream of the archipelago, and warm wake regions protected from the Trade winds by the high volcanic peaks of the islands. The filament is shown to be a recurrent feature, apparently arising from the interaction of a topographically trapped cyclonic eddy with the outer edge of the coastal upwelling zone. Its role in the transport and exchange of biogenic material, including fish larvae, is considered. Strong cyclonic eddies, observed throughout the year, drift slowly southwestward from Gran Canaria. One sampled in late summer was characterised by large vertical isopycnal displacements, apparent surface divergence and strong upwelling, producing a fourfold increase in chlorophyll concentrations over background values. Such intense eddies can be responsible for a major contribution to the vertical flux of nitrogen. The lee region of Gran Canaria is shown to be a location of strong pycnocline deformation resulting from Ekman pumping on the wind shear boundaries, which may contribute to the eddy formation process.

In this paper, we studied of photoelectric properties of multilayer organic photovoltaic cells (OPV cells). The active organic layers consisted of a planar heterojunction between a layer of (meso-tetrakis(5-bromo-2-thienyl)porphyrin), (TBrTP) as electron donor (ED) and a layer fullerene molecules. For the manufacture of photovoltaic devices we use a the technique of high vacuum by thermal sublimation that allows multilayer devices realization easily by successive depositions, and it does not require solvents, achieving purer films with reproducible characteristics. The TBrTP allows achieving OPVCs exhibiting promising efficiencies when the ABL is the MoO 3/ CuI DABL. The CuI improves the current in the organic layer by one order of magnitude, which allows decreasing the series resistance of the OPVCs and therefore improving the OPVCs.

In the present work a series of β-substituted thiophenes have been synthesized and their electrochemical behavior studied. The products obtained by electro-oxidation are highly dependent on the substituent, affording sometimes conducting polymers, insulating layers or soluble species. This behavior has been ascribed to specific electronic and/or steric factors. Theoretical calculations at the density functional theory level confirm the experimental findings and assess the use of reactivity descriptors for modeling complex chemical systems with specific polymerization patterns. In particular, the analysis of the polymerization sites of terthiophene derivatives using the dual descriptor for chemical reactivity and selectivity allows one to predict the specific sites able for reaction and explains correctly the observed polymerization pattern.

The synthesis of 6-ami no-5-nitro-4-thioxo-pyrimidines starting from the C-adducts of nitro-keteneaminals and acyl isothiocyanates is described.

In the present work the electrochemical study of compounds based on 3-((ω-bromoalkyloxy) methyl) thiophene, varying the length of the alkyl chain between 6 and 12 carbon atoms, is reported. Electropolymerization of the monomers was achieved by potentiodynamic (cyclic voltammetry, CV) and potentiostatic (constant potential) techniques. Voltammograms obtained by CV show that all monomers can be electrochemically oxidized at potentials about 1800 mV to synthesize the respective polymer. Besides, the potential shifts to more anodic potentials on successive scans, increasing thus the resistivity of the material. Nucleation and growth mechanism (NGM) of electropolymerization was investigated by a potentiostatic technique ( j – t ). Deconvolution of the current–time transient data fitted with a theoretical model suggests that at short times the instantaneous nucleation with two-dimensional growth (IN2D) contribution prevails, followed by an instantaneous nucleation with three-dimensional growth controlled by the charge transfer (IN3Dct) contribution and, finally at longer times, the instantaneous nucleation with three-dimensional growth controlled by diffusion (IN3Ddif) contribution becomes important. The predominance of each contribution to the NGM depends on the monomer being electropolymerized, and the electrolysis time. The morphology predicted from these NGMs fully correlates with that determined by SEM.

Recent studies on conducting polymers have demonstrated that polymers of 3-substituted thiophene produce very stable compounds. Although this kind of substitution improves the regularity, structural defects still exist. To overcome this drawback, the polymerization of 3,4-disubstituted thiophene is proposed as a convenient way of synthesizing regular, highly conjugated conductive polymers. Our interest is thus focused on the synthesis of tetra-substituted thiophene derivatives, their polymerization, electrochemical properties, spectral characteristics, oxidizing potential, and the feasibility of photocells development. In this article, we report the synthesis and characterization of 3′,4′-dibromo-2,2′:5′,2″-terthiophene which, as such or modified, may be a good starting product for obtaining new monomers of 3′,4′-disubstituted terthiophenes, that would allow the effect of the substituents on the properties of the respective polymers to be studied. In addition, the monomer was electropolymerized and the resulting deposit was electrochemically and morphologically characterized. Two conclusions were drawn: first, more uniform and homogeneous layers than those of polythiophene are obtained; second, the thin layers of the polymer, electron acceptors, absorb in the visible. Finally, photocells were assembled to investigate their photovoltaic effect. Although the so prepared solar cells showed some photovoltaic effect, the yield was low.© 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5314–5321, 2006

Young red tilapias were exposed for 96 h to each one of 6 concentrations of the pesticide Diazinon in order to determine the pesticide's acute toxicity level. After the ascertaining the lethal concentration (LC50) at 96 h, a level 10 times lower was selected for the bioaccumulation study of the pesticide in male and female specimens exposed for 9 days. The elimination process was carried out for 10 days beginning right after the conclusion of the accumulation process. Analytical procedures were developed and used for the studies of acute toxicity and bioaccumulation of Diazinon in red tilapia. A lethal concentration [LC50 (96 h)] of 3.85 mg/L was found, and steady-state accumulation, at a concentration of 28.45 mg/kg, was reached at 7.72 days. In the elimination process a concentration of 0.29 mg/kg was found in tilapia tissue by the sixth day after the fish were moved to clean water, and it continued to decrease quickly toward nondetectable levels.

This is the first national study of breast-cancer knowledge, beliefs, and early detection practices among elderly women (65+) in Puerto Rico. Cancer breast examination (CBE) was the most common early detection practice, followed by the mammogram, with breast self exam (BSE) a distant third. The primary reasons most often cited for never having a mammogram related to both personal and external factors: not having symptoms, negligence or forgetfulness, and not having a physician's referral. No statistically significant difference (p0.05) was found between knowledge and early detection practices. Conversely, beliefs had an impact on preventive behavior. Those who had less misconceptions were most likely to have had a CBE or a mammogram. Bivariate analysis demonstrated that age was associated with performing a BSE once or twice monthly, ever having a mammogram, and having a mammogram in the past two years. A higher socioeconomic status was associated to performing BSE and ever having had a mammogram. Education correlated positively to ever having a mammogram or having a mammogram in the two years prior to the interview. Factors that explained compliance with a mammogram in the last two years included referral from a physician, owning a car, and receiving information after menopause on breast cancer from a health care provider. A gynecological visit increased the probability of having had a mammogram during the last two years. Logistic regression determined that a referral from a physician was the most important factor for mammogram compliance when a combination of variables were considered.

In order to plan the health services for the elderly population, it is necessary to quantify their health status and their functional capacity. In Puerto Rico, few epidemiological studies have been conducted regarding functional capacity and chronic diseases in the elderly population. One of the difficulties to undertake these studies is the high cost and risks to move this population for clinical exams, in addition to the methodology limitation of self-report in the elderly population. This study shows the use of logistic regression to estimate the prevalence of chronic diseases and functional capacity, when the observed data are not consisted with the planed sampling scheme. Four hundred and eighty-seven elderly persons (65 yr. and over) were interviewed in the municipalities of Canóvanas, Carolina, Loíza and Trujillo Alto in Puerto Rico, using a cross-sectional design. More than half of the elderly had visual problems (IC 95%: 54.8%, 63.8%), arthritis (IC 95%: 52.7%, 61.5%) and hypertension (IC 95%: 47.3%, 56.3%). In the case of hypertension, significant differences (p0.05) by sex were observed, where women reported a higher prevalence than men. One of the higher prevalences in the functional capacity status was with urine accidents. More than one-third of the population is estimated to have this problem (IC 95%: 34.7%, 43.4%). One-fourth of the population had limitations with going out for shopping (IC 95%: 23.9%, 31.9%) and using public and private transportation (IC 95%: 19.5%, 26.9%). We conclude that the applied methodology was consistent with the estimation presented in the literature and statistics from the Puerto Rico Health Department. However, it is necessary to continue assessing the design and analytical methodology, in order to undertake consistent and periodic evaluations of the elderly population.

This paper presents the results of the validation process to determine the concepts for knowledge and beliefs about breast cancer early detection practices among Puerto Rican elderly women. An initial questionnaire was designed based on the scientific literature review and focus group experiences. To determine its reliability and validity, 50 elderly women, stratified by type of profession and place of residence, were interviewed twice. Consistency of the questionnaire was analyzed using binomial test, matched t-test, Pearson correlation coefficient, and Cronbach's coefficient effect. Factor analysis (FA) was the statistical technique used to analyze the grouping of the knowledge and beliefs statements. FA indicated that three scales for knowledge and one for beliefs can be constructed. The purpose of the scales was to identify differences among groups, according to breast cancer early detection practices. Construct validity was performed to determine the number of statistical associations between the scales and these practices. The results showed that beliefs scales was associated with practice of mammogram (p0.05), and visit to the gynecologist (p0.05) while the knowledge scale for early-detection was associated with the clinical breast examination (p0.05). The beliefs scale had better consistency than the knowledge scale. The Cronbach's alpha was 0.75 for the beliefs' scale and 0.30, 0.41 and 0.43 for each defined knowledge scale, respectively.

Pedazos de 115 g de ñame Habanero (Dioscorea rotundata Poir) de alta calidad se trataron par una hora con fungicidas, 48 horas antes de sembrarlos para determinar el efecto sobre el brote y el rendimiento. Se escogió un predio experimental que no había estado sembrado de ñames previamente y estaba libre de nematodos parásitos del ñame. Se registró, 91 , 95 y 96% de brote en los pedazos tratados con captan + benomyl, captan, y captan + thiabendazole, respectivamente, comparado con 52% en los que no se trataron con fungicida (testigo). El brote temprano (5 semanas después de la siembra) fue mayor en los pedazos tratados con captan + thiabendazole (24%) que en los tratados con captan + benomyl (1%), con captan (2%) o el testigo (1%). A las 9 semanas, los tratamientos con fungicidas no fueron diferentes significativamente en el porcentaje de pedazos que brotaron (91-96%). Se determinaron correlaciones positivas entre el porcentaje de pedazos que brotaron y el rendimiento (r = 0.77**); el número total de tubérculos cosechados (r = 0.84**) y el peso medio de los tubérculos (r = 0.74**). El testigo produjo más tubérculos por planta (1.64) que los tratados con fungicidas (1.16-1.20). Las pérdidas en el rendimiento del testigo (48%) estuvieron asociadas con las pérdidas en el peso por tubérculo (37%) y con el total producido por área (20%). Se registró un mayor rendimiento tanto por planta como por área y por tubérculo en los que se trataron con captan + thiabendazole que con captan o captan + benomyl. Los factores que determinan la producción total y el tamaño de los tubérculos son el brote más temprano y el brote de un número mayor de pedazos. En este estudio aún cuando se seleccionaron tubérculos de alta calidad y se sembraron en condiciones óptimas, el brote y el rendimiento se redujo casi a la mitad cuando los pedazos no se trataron con un fungicida antes de sembrarlos.

Twenty five cases of onychomycosis due to filamentous saprophytic agents were diagnosed within the period 1981-1982 in two mycology laboratories in Medellín, Colombia. These cases represented 4.5% and 9.5% respectively of the total fungal nail lesions (FNL) seen at those institutions. No explanation was found for the high frequencies, which sharply contrast with the previous local experience with the disease (0.4% of FNL). The responsible agents belonged to the following genera in decreasing order of frequency: Fusarium, Aspergillus, Scopulariopsis, Penicillium and Lasiodiplodia; two patients were infected with unidentified dematiaceous fungi and two more had the association of a saprophyte and a dermatophyte. In every case direct KOH preparations revealed septate hyphae, associated in 14 patients (56%) with chlamydoconidia. The only predisposing factors that were common to all these patients were age above 20 years and the use of footwear.

The electrical resistivity of liquid alloys in the system In-Sb has been determined using a.d.c. four probe method. The resistivities range from 40 to 120μΩ cm and show a positive temperature dependence. A maximum in electrical resistivity is observed at compositions close to that of the inter-metallic compound InSb. Such a compound behaves as a semiconductor in the solid state and as a metal in the liquid state. Maxima are found in the reduced resistivity and in the excess thermodynamic stability at about 50 at % Sb.

A collaborative study of nutritional anemia in third trimester pregnancy was performed in seven Latin American countries. Laboratory measurements included hemoglobin level, mean corpuscular hemoglobin concentration (MCHC), serum iron and iron-binding capacity, serum folate, vitamin B12 and albumin. Iron deficiency (transferrin saturation below 15%) was found in 48% of pregnant women, as compared with 21% of nonpregnant females and 3% of male controls of comparable age. The prevalence of folate deficiency (serum folate below 3 ng/ml.) was 10%, 10% and 9% in these three groups, respectively. Vitamin B12 deficiency (serum level below 80 pg/ml.) was found in 15% of pregnant women, but in less than 1% of both control groups. Anemia, as defined by current WHO criteria, was found in 38.5% of pregnant women, 17.3% of nonpregnant women and 3.9% of men. Analysis of the frequency distribution for hemoglobin levels, based on a Gaussian distribution in normal subjects, suggested that a large portion of subjects considered anemic by WHO criteria were normal and that the true incidence of anemia in pregnant and nonpregnant females was 22 and 12% respectively. Correlation analysis indicated that iron deficiency was of major importance as a cause of anemia, while folate lack was contributory only in pregnancy; no relationship could be demonstrated between vitamin B12 deficiency and anemia.

Serum electrophoresis patterns and various measures of specific and non-specific immune competence were determined in 16 patients with paracoccidioidomycosis, at time of diagnosis and 6 months after therapy. The results were compared with those furnished by the study of 16 control subjects, matched by age and sex. Once treated, the patients approached normality in some parameters. Untreated patients had significantly diminished albumin levels with increased alpha 1, alpha 2 and gamma fractions. Immune gamma globulin G (IgG) was elevated and remained so during therapy. Both before and after treatment patients had diminished total numbers and decreased percentages of E rosettes; they also had depressed lymphocyte transformation with phytohemagglutinin (PHA) and paracoccidioidin (P). Also, untreated patients exhibited the lowest skin test responses to PHA, purified protein derivative (PPD), P and candidin (C); significant differences, however, were limited to the former 2 antigens. All untreated patients had detectable antibody titers against P. brasiliensis; these titers had a tendency to drop during treatment. No direct correlation was found between elevated serum fractions, presence of antibodies and depressed cellular immunity.