Examinando 3.2 Pasantías y ponencias por Fecha de asunto

Publicación

Chronic hypoxia induces modification of the N-methyl-D-aspartate receptor in rat brain

(Elsevier, 1996)

Pichiule P.

;

Chávez J.C.

;

Boero J.

;

Arregui A.

This study examined [3H]MK-801 binding to the N-methyl-D-aspartate (NMDA) receptor in membranes prepared from cerebral cortex, hippocampus and corpus striatum of 3 week old rats exposed to 10 weeks of intermittent hypobaric hypoxia (4300 m; 450 Torr) and compared results wiLh those of normoxic controls. The cortex, hippocampus and striatum of hypoxic animals had a 36, 35 and 31% reduction in binding sites (Bmax) and a 29, 32 and 17% decrease (reflecting increased affinity) in the dissociation constant (Kd) when compared to controls. In the cerebral cortex, both glutamate (100 #M) and glycine (10 #M) enhanced [3H]MK-801 binding by two to 3- fold: Coagonist glutamate, however, had a higher ECs0 (0.44 #M) in the hypoxic cortical membranes when compared to controls (0.28 #M). No significant differences were found in the ECs0 of glycine. The results show that the NMDA receptor is altered in several brain regions of rats developing in a hypoxic environment.

Publicación

Zooplankton volume trends off Peru between 1964 and 2001

(Oxford University Press, 2004)

Ayón P.

;

Purca S.

;

Guevara-Carrasco R.

Zooplankton samples were collected by Hensen net (300 mm) vertical hauls from a depth of 50 m in 57 surveys along the Peruvian coast during winter and summer from 1961 to 2001. In general, the latitudinal distribution of total zooplankton volumes showed highest values within 60 nmi (111 km) of the coast. Predominantly during the 1960s, high zooplankton volumes were found between 4(Se6(S and 14(Se16(S, coinciding with narrow continental shelf areas. Strong declines of zooplankton volumes were observed in these regions in the 1990s. In the long term, zooplankton volumes off Peru were higher during ‘‘cold’’ decades, particularly in the 1960s, than during ‘‘warm’’ decades. This research supports the regime-shift previously observed in the Peruvian coastal upwelling, and is in agreement with global changes observed in lower and upper trophic levels elsewhere in the Pacific and North Atlantic basins.

Publicación

The use of natural product scaffolds as leads in the search for trypanothione reductase inhibitors

(Elsevier Ltd, 2008)

Galarreta B.C.

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Sifuentes R.

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Carrillo A.K.

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Sanchez L.

;

Amado M.d.R.I.

;

Maruenda H.

Twenty-three heterocyclic compounds were evaluated for their potential as trypanothione reductase inhibitors. As a result, the harmaline, 10-thiaisoalloxazine, and aspidospermine frameworks were identified as the basis of inhibitors of Trypanosoma cruzi trypanothione reductase. Two new compounds showed moderately strong, linear competitive inhibition, namely N,N-dimethyl-N-[3-(7-methoxy-1- methyl-3,4-dihydro-9H-b-carbolin-9-yl)propyl]amine (15) and 1,3-bis[3-(dimethylamino)propyl]-1,5- dihydro-2H-pyrimido[4,5-b][1,4]benzothiazine-2,4(3H)-dione (21), with Ki values of 35.1 ± 3.5 lM and 26.9 ±1.9 lM, respectively. Aspidospermine (25) inhibited T. cruzi TryR with a Ki of 64.6 ± 6.2 lM. None of the compounds inhibited glutathione reductase. Their toxicity toward promastigotes of Leishmania amazonensis was assessed.

Publicación

Antioxidant properties of mashua (Tropaeolum tuberosum) phenolic extracts against oxidative damage using biological in vitro assays

(Elsevier Ltd, 2008)

Chirinos R.

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Campos D.

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Warnier M.

;

Pedreschi R.

;

Rees J.-F.

;

Larondelle Y.

Purified mashua extracts (PME) from four different coloured mashua genotypes were assayed for oxidative damage prevention. Three in vitro assays for oxidative damage to biological structures rich in polyunsaturated fatty acids (PUFA), such as LDL and erythrocytes, were tested: AAPH-induced TBARS assay and Cu2+-induced conjugated dienes assay for LDL oxidation and AAPH-induced oxidative hemolysis of erythrocytes. Additionally, ORAC antioxidant capacity, total phenolics (TP), total flavanoids (TFA) and total anthocyanins (TA) were evaluated. In the presence of 5 lM of gallic acid equivalents (GAE), inhibitions of LDL oxidation for the PME ranged from 29.1% to 34.8% and from 51.8% to 58.1% when the TBARS and conjugated dienes assays were performed, respectively. PME inhibited the hemolysis of erythrocytes within the range 20.8–25.1%. Thus, mashua phenolic extracts are capable of scavenging peroxyl radicals, as well as chelating redox metal ions in vitro. ORAC and LDL protection (TBARS and conjugated dienes assays) showed good correlations with the TP and TFA, suggesting that these compounds have a good ability to protect LDL molecules under the employed conditions. In contrast, inhibition of hemolysis did not show any correlation with the evaluated phenolic assays (TP, TA, TFA) or with any of the evaluated oxidative LDL assays, suggesting a specific action of some non-evaluated compounds present in the PME. The results of this study indicate that the mashua polyphenol extracts displayed good antioxidant properties against oxidative damage in biological structures rich in PUFA. The displayed antioxidant properties could be applied in the field of food or cosmetic industry.

Publicación

Influence of water status on mineral composition of berries in 'Grenache Noir' (Vitis vinifera L.)

(Julius Kuhn-Institut Federal Research Center for Cultivated Plants, 2009)

Etchebarne, F

;

Ojeda, H

;

Deloire, A

The influence of vine water status on the seasonal changes of fresh weight, dry matter and the levels of potassium and calcium in grape-berries on field vines of 'Grenache Noir' (Vitis vinifera L.), was studied over a two-year period. Two levels of water status, irrigated and non-irrigated, were investigated using a single level of total leaf surface - each primary shoot was confined to ten leaves, one grape bunch, and the secondary shoots were removed as they appeared. The mineral element contents were determined separately in different fruit compartments, i.e. the skin, flesh and seeds. Potassium and calcium accumulate independently of one another, but their seasonal change in the fruit and their final quantities in the berry depend principally on plant water status. The accumulation of potassium parallels the change in fruit fresh weight; approximately 50 % of the final content was accumulated pre-veraison and loading continued during berry ripening. This report shows that a small quantity of calcium may accumulate throughout fruit ripening phases in situations where water supply is not a limiting factor. These results imply that fruit xylem is functioning partially during ripening. Moreover, in both water status situations, the quantity of calcium in the skin increases during ripening, which suggests apoplastic and/or symplastic migration in the berry.

Publicación

IFN-gamma production in response to Tax 161-233, and frequency of CD4(+) Foxp3(+) and Lin(-) HLA-DRhigh CD123(+) cells, discriminate HAM/TSP patients from asymptomatic HTLV-1-carriers in a Peruvian population

(Wiley-Blackwell Publishing Ltd, 2009)

Best, I

;

Lopez, G

;

Verdonck, K

;

Gonzalez, E

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Tipismana, M

;

Gotuzzo, E

;

Vanham, G

;

Clark, D

Human T-lymphotropic virus 1 (HTLV-1) can cause HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The objective of this study was to gain insight into the pathogenesis of HAM/TSP by focusing on the CD8(+) T-cell response. Twenty-three HTLV-1-seronegative controls (SC), 29 asymptomatic HTLV-1 carriers (AC) and 48 patients with HAM/TSP were enrolled in the study. We evaluated the production of interferon-gamma (IFN-gamma) in peripheral blood mononuclear cells stimulated with Tax overlapping peptides, the expression of genes related to the CD8(+) cytotoxic T-cell response, the frequency of CD4(+) Foxp3(+) cells and of dendritic cells, and the HTLV-1 provirus load (PVL). The frequency of cells producing IFN-gamma in response to Tax 161-233, but not to Tax 11-19, discriminated patients with HAM/TSP from AC. The increased pro-inflammatory response observed in patients with HAM/TSP was shared by AC with a high PVL, who also exhibited lower levels of granzyme H mRNA in unstimulated CD8(+) T cells than AC with a low PVL. Patients with HAM/TSP showed higher frequencies of CD4(+) Foxp3(+) cells and lower frequencies of plasmacytoid dendritic cells (pDC) than AC. Our findings are consistent with a model in which HTLV-1, along with the host genetic background, drives quantitative and qualitative changes in pDC and CD4(+) Foxp3(+) cells that lead to a predominance of inflammatory responses over lytic responses in the CD8(+) T-cell response of individuals predisposed to develop HAM/TSP.

Publicación

Notas sobre tres especies de Gigartinaceae (Rhodophyta) del litoral peruano [Notes on three species of Gigartinaceae (Rhodophyta) from Peruvian coast]

(Facultad de Ciencias Biologicas, Universidad Nacional Mayor de San Marcos, 2010)

Calderón M.

;

Ramírez M.E.

;

Bustamante D.

La gran variabilidad morfológica de la familia Gigartinaceae ha producido constantes cambios taxonómicos en sus especies miembros. Tradicionalmente su taxonomía ha estado basada en caracteres de la morfología externa; sin embargo, recientes estudios morfológicos, respaldados con trabajos moleculares, han delimitado los géneros en base a al desarrollo del cistocarpo y de los tetrasporangios. El presente trabajo revisa y comenta sobre las estructuras morfológicas vegetativas y reproductivas de tres especies presentes en Perú: Chondracanthus chamissoi, Mazzaella denticulata y Chondrus canaliculatus.

Publicación

Sexual Dysfunction Risk and Associated Factors in Young Peruvian University Women

(Blackwell Publishing Ltd, 2011)

Escajadillo-Vargas N.

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Mezones-Holguín E.

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Castro-Castro J.

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Córdova-Marcelo W.

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Blümel J.E.

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Pérez-López F.R.

;

Chedraui P.

Assess female sexual dysfunction (FSD) risk and associated factors in young Peruvian university women. The method used was a nested case-control study, using the Female Sexual Function Index (FSFI). Cases were defined as women with total FSFI scores at or below 26.55 (increased FSD risk). Demographic characteristics, gynecologic aspects, body mass index, mood disorders, substance abuse, and issues related to the couple, were also evaluated.

Publicación

A new Clathria (Demospongiae, Microcionidae) from Peru occurring on rocky substrates as well as epibiontic on Eucidaris thouarsii sea urchins

(Magnolia Press, 2011)

Aguirre, LK

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Hooker, Y

;

Willenz, P

;

Hajdu, E

Southeastern Pacific sponges (Phylum Porifera) range among the world’s least known faunas, with only 13 species reported to date from the entire Peruvian coast. This state of affairs motivated the onset of two large, cooperative, exploratory initiatives, with the aim of mapping sponge richness and distribution in the area: Proyectos ESPER and EsponjAS. Over 800 specimens have been collected in Peru since 2007, with identifications still in progress. Among these, a sponge species originally thought to be an exclusive epibiont on Eucidaris thouarsii sea urchins, relatively conspicuous on Peru’s Punta Sal region. This sponge, latter found to occur on additional substrates too, is described as a new species of Clathria (Microciona). Cidarid density ranged between 1.5 and 12/m2 , and largest diameter of the tests between 3.2 and 5.6 cm. Total number of spines on each sea urchin varied between 68 and 96, and percent sponge coverage of these, between 18.2 and 75.7. There appears to be only a slight tendency for increased sponge coverage on larger sea urchins, so there may be factors, other than sea urchin age, shaping this association. Clathria (Microciona) aculeofila sp. nov. can be markedly dominant as an epibiont on E. thouarsii, albeit the great sponge richness in the area. This is in contrast to the allegedly opportunistic, diverse epibiosis by sponges reported previously for Antarctic cidaroids

Publicación

Short Communication An Interferon-gamma ELISPOT Assay with Two Cytotoxic T Cell Epitopes Derived from HTLV-1 Tax Region 161-233 Discriminates HTLV-1-Associated Myelopathy/Tropical Spastic Paraparesis Patients from Asymptomatic HTLV-1 Carriers in a Peruvian Population

(Mary Ann Liebert, 2011)

Best, I

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Lopez, G

;

Talledo, M

;

MacNamara, A

;

Verdonck, K

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Gonzalez, E

;

Tipismana, M

;

Asquith, B

;

Gotuzzo, E

;

Vanham, G

;

Clark, D

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic and progressive disorder caused by the human T-lymphotropic virus type 1 (HTLV-1). In HTLV-1 infection, a strong cytotoxic T cell (CTL) response is mounted against the immunodominant protein Tax. Previous studies carried out by our group reported that increased IFN-γ enzyme-linked immunospot (ELISPOT) responses against the region spanning amino acids 161 to 233 of the Tax protein were associated with HAM/TSP and increased HTLV-1 proviral load (PVL). An exploratory study was conducted on 16 subjects with HAM/TSP, 13 asymptomatic carriers (AC), and 10 HTLV-1-seronegative controls (SC) to map the HAM/TSP-associated CTL epitopes within Tax region 161–233. The PVL of the infected subjects was determined and the specific CTL response was evaluated with a 6-h incubation IFN-γ ELISPOT assay using peripheral blood mononuclear cells (PBMCs) stimulated with 16 individual overlapping peptides covering the Tax region 161–233. Other proinflammatory and Th1/Th2 cytokines were also quantified in the supernatants by a flow cytometry multiplex assay. In addition, a set of human leukocyte antigen (HLA) class I alleles that bind with high affinity to the CTL epitopes of interest was determined using computational tools. Univariate analyses identified an association between ELISPOT responses to two new CTL epitopes, Tax 173–185 and Tax 181–193, and the presence of HAM/TSP as well as an increased PVL. The HLA-A*6801 allele, which is predicted to bind to the Tax 181–193 peptide, was overpresented in the HAM/TSP patients tested.

Publicación

Genome-Wide Identification and Mapping of NBS-Encoding Resistance Genes in Solanum tuberosum Group Phureja

(PLOS, 2012)

Lozano, R

;

Ponce, O

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Ramirez, M

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Mostajo, N

;

Orjeda, G

The majority of disease resistance (R) genes identified to date in plants encode a nucleotide-binding site (NBS) and leucine-rich repeat (LRR) domain containing protein. Additional domains such as coiled-coil (CC) and TOLL/interleukin-1 receptor (TIR) domains can also be present. In the recently sequenced Solanum tuberosum group phureja genome we used HMM models and manual curation to annotate 435 NBS-encoding R gene homologs and 142 NBS-derived genes that lack the NBS domain. Highly similar homologs for most previously documented Solanaceae R genes were identified. A surprising ∼41% (179) of the 435 NBS-encoding genes are pseudogenes primarily caused by premature stop codons or frameshift mutations. Alignment of 81.80% of the 577 homologs to S. tuberosum group phureja pseudomolecules revealed non-random distribution of the R-genes; 362 of 470 genes were found in high density clusters on 11 chromosomes.

Publicación

ROOT-KNOT NEMATODES FROM ASPARAGUS AND ASSOCIATED BIOLOGICAL ANTAGONISTS IN PERU

(Organization of Nematologists of Tropical America, 2012)

Murga-Gutierrez, SN

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Colagiero, M

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Rosso, LC

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Sialer, MMF

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Ciancio, A

Murga-Gutierrez S. N., M. Colagiero, L. C. Rosso, M. M. Finetti Sialer, and A. Ciancio. 2012. Root-knot nematodes from asparagus and associated biological antagonists in Peru. Nematropica 42:57-62. A research study on the parasitic nematodes of asparagus and several associated antagonists was carried out in Northern Peru. Nematodes were identified by means of light microscopy and sequencing of the ITS1-2 regions. Nematophagous fungi were isolated from nematode-infested roots or soil, cultured in vitro and maintained in a culture collection for further characterization. The species recovered were mainly root-knot nematodes including Meloidogyne incognita and M. ethiopica. Nematophagous fungi identified through standard morphological methods as well as by ITS sequencing included Drechslerella brochopaga, Lecanicillium psalliotae and Monacrosporium sp. Meloidogyne ethiopica and the antagonistic fungi are new records for the country.

Publicación

Determination of the Absolute Configuration of 19-OH-(-)-eburnamonine Using a Combination of Residual Dipolar Couplings, DFT Chemical Shift Predictions, and Chiroptics

(SAGE Publications Inc., 2012)

Trigo-Mourino, P

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Sifuentes, R

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Navarro-Vazquez, A

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Gayathri, C

;

Maruenda, H

;

Gil, RR

19-OH-(-)-eburnamonine 1 is a new indole alkaloid isolated from Bonafusia macrocalyx. A natural derivative from (-)-eburnamonine for which absolute configuration and conformation has been determined by making use of residual dipolar couplings enhanced NMR, circular dichroism spectra and high-level computations.

Publicación

Resistance of Fasciola hepatica against Triclabendazole in cattle in Cajamarca (Peru): A clinical trial and an in vivo efficacy test in sheep

(Elsevier B.V., 2013)

Ortiz, P

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Scarcella, S

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Cerna, C

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Rosales, C

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Cabrera, M

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Guzman, M

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Lamenza, P

;

Solana, H

Fasciolosis caused by Fasciola hepatica, is the most prevalent parasitic disease in dairy cattle from the northern region of Cajamarca, Peru. The control of this parasite is based on the use of Triclabendazole (TCBZ), a drug that has been used for more than fifteen years in this area. Recent studies, however, have reported a lack of clinical efficacy after treating dairy cattle. This research was aimed to determine the efficacy of TCBZ in a clinical trial.

Publicación

Construction of Reference Chromosome-Scale Pseudomolecules for Potato: Integrating the Potato Genome with Genetic and Physical Maps

(Genetics Society of America, 2013)

Sharma, SK

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Bolser, D

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de Boer, J

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Sonderkaer, M

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Amoros, W

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Carboni, MF

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D'Ambrosio, JM

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de la Cruz, G

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Di Genova, A

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Douches, DS

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Eguiluz, M

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Guo, X

;

Guzman, F

;

Hackett, CA

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Hamilton, JP

;

Li, GC

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Li, Y

;

Lozano, R

;

Maass, A

;

Marshall, D

;

Martinez, D

;

McLean, K

;

Mejia, N

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Milne, L

;

Munive, S

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Nagy, I

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Ponce, O

;

Ramirez, M

;

Simon, R

;

Thomson, SJ

;

Torres, Y

;

Waugh, R

;

Zhang, ZH

;

Huang, SW

;

Visser, RGF

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Bachem, CWB

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Sagredo, B

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Feingold, SE

;

Orjeda, G

;

Veilleux, RE

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Bonierbale, M

;

Jacobs, JME

;

Milbourne, D

;

Martin, DMA

;

Bryan, GJ

The genome of potato, a major global food crop, was recently sequenced. The work presented here details the integration of the potato reference genome (DM) with a new sequence-tagged site marker2based linkage map and other physical and genetic maps of potato and the closely related species tomato. Primary anchoring of the DM genome assembly was accomplished by the use of a diploid segregating population, which was genotyped with several types of molecular genetic markers to construct a new ~936 cM linkage map comprising 2469 marker loci. In silico anchoring approaches used genetic and physical maps from the diploid potato genotype RH89-039-16 (RH) and tomato. This combined approach has allowed 951 superscaffolds to be ordered into pseudomolecules corresponding to the 12 potato chromosomes. These pseudomolecules represent 674 Mb (~93%) of the 723 Mb genome assembly and 37,482 (~96%) of the 39,031 predicted genes. The superscaffold order and orientation within the pseudomolecules are closely collinear with independently constructed high density linkage maps. Comparisons between marker distribution and physical location reveal regions of greater and lesser recombination, as well as regions exhibiting significant segregation distortion. The work presented here has led to a greatly improved ordering of the potato reference genome superscaffolds into chromosomal “pseudomolecules”.

Publicación

Phylogeny and morphology of Hirsutella tunicata sp nov (Ophiocordycipitaceae), a novel mite parasite from Peru

(Elsevier, 2013)

Ciancio, A

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Colagiero, M

;

Rosso, LC

;

Gutierrez, SNM

;

Grasso, G

A new species of Hirsutella was isolated from unidentified mites on Petri plates inoculated with soil and root fragments collected from asparagus rhizosphere at Viru´ , Northern Peru. The fungus differs from other Hirsutella species by an envelope surrounding the conidium, conidia dimension and DNA sequences. In PDA cultures, the mycelium produced aerial hyphae with conidiogenous cells mainly at right angles, occasionally showing a secondary conidiophore. The solitary conidia are cymbiform, slightly apiculate, 5.0e6.0 3.0e4.0 mm. Phylogenetic analyses with partial rRNA and b-tubulin gene sequences confirmed the fungus as an Hirsutella (Ophiocordycipitaceae). Closest species shown by maximum likelihood and neighbor-joining trees were H. nodulosa and H. aphidis, from which the new species differs for conidium or conidiogenous cells dimensions, lack of synnemata and host type. A recombination event was also detected in the rRNA of the holotype strain, involving Ophiocordyceps sinensis as major parent and O. cochlidiicola as minor parent. A complement, inverted insertion was also found in its rRNA, involving part of the ITS2 and 5.8S regions, flanked by two short nucleotide arrays. Due to conidia dimension and phylogenetic position, the fungus is described as Hirsutella tunicata sp. nov. A review of mononematous Hirsutella species is provided.

Publicación

Multilayered artifacts in the pre-Columbian metallurgy from the North of Peru Multilayered artifacts in the pre-Columbian metallurgy from the North of Peru

(Springer Heidelberg, 2013)

Cesareo, R

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Bustamante, AD

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Fabian, JS

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Zambrano, SD

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Alva, W

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Chero, LZ

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Espinoza, MCD

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Rodriguez, RR

;

Seclen, MF

;

Gutierrez, FV

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Levano, EB

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Gonzales, JA

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Rizzutto, MA

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Poli, E

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Calza, C

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Dos Anjos, M

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De Freitas, RP

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Lopes, RT

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Elera, C

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Shimada, I

;

Curay, V

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Castillo, MG

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Gigante, GE

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Ingo, GM

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Lopes, F

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Holmquist, U

;

Diestra, D

Three types of alloys were recognized when analyzing pre-Columbian artifacts from the North of Peru: gold, silver, and copper alloys; gilded copper and silver; silvered copper; tumbaga, i.e., copper or silver enriched on gold at the surface by depletion gilding. In this paper, a method is described to differentiate gold alloys from gilded copper and from copper-gold tumbaga, and silver alloys from silvered copper and copper-silver tumbaga. This method is based on the use of energy-dispersive X-ray fluorescence, i.e., on a sophisticated analysis of XRF-spectra carrying out an accurate determination of Cu(K α /K β ), Ag(K α /K β ), Au(L α /L β ), and Au-L α /Cu-K α or Ag-K α /Cu-K α ratios. That implies a dedicated software for the quantitative determination of the area of X-ray peaks. This method was first checked by a relevant number of standard samples and then it was applied to pre-Columbian alloys from the North of Peru. © 2013 Springer-Verlag Berlin Heidelberg.

Publicación

Computer Aided Medical Diagnosis Tool to Detect Normal/Abnormal Studies in Digital MR Brain Images

(IEEE Xplore, 2014)

Gutierrez-Caceres, J

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Portugal-Zambrano, C

;

Beltran-Castanon, C

This work presents a model to support medical diagnosis through the classification of abnormality normality in medical brain images, in order to help to specialist as a previous step in the brain pathology diagnosis. Our proposal was incorporated into a content-based image retrieval system, thus we developed a useful tool for radiologists. The first step produces the features vector of MR image using Gabor Filter for the data train and test, then as second step features vector of training data are indexed into CBIR module. The third step makes the training of SVM and as four step the test dataset is classified with the SVM trained. Finally, the result of classification are presented with a set of similar images product of a KNN query. This model was implemented as a software tool with graphical interface. We obtained 94.12% of correct classification. Our medical image dataset is composed of 187 MRI images collected from a medical diagnosis company and selected by medical specialist. The result shows that the proposed model is robust and effective as a software tool to aid support to medical diagnostic.

Publicación

Influence of pyrolytic seeds on ZnO nanorod growth onto rigid substrates for photocatalytic abatement of Escherichia coli in water

(IWA Publishing, 2014)

Sanchez, L

;

Guz, L

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Garcia, P

;

Ponce, S

;

Goyanes, S

;

Marchi, MC

;

Candal, R

;

Estrada, W

;

Rodriguez, J

ZnO nanorods (ZnO NRs) were grown on ZnO seeded fluorine doped tin oxide (FTO) substrates at low temperatures (90 W C) from Zn2þ precursors in alkaline aqueous solution. The ZnO seeds were deposited on the FTO substrate heated at 350 W C by spray pyrolysis of a zinc acetate solution in a water ethanol mixture. The structure of seeds was tuned by the ethanol water ratio, Γ, which controls the solvent evaporation rate of drops impinging the substrate. The relationship between the microstructure and optical properties of the ZnO NR films and the photocatalytic antibacterial activity for Escherichia coli abatement, was determined through a detailed characterization of the material. The higher photocatalytic antibacterial activity was performed by ZnO NR films grown on seeds deposited from solutions with Γ in the 0.0–0.03 range. With these films, the population of viable E. coli dropped more than six orders, from 8 × 108 to 4 × 102 CFU. These results show the potential of these materials in water disinfection.

Publicación

The polar family of webs and foliations

(Springer New York, 2014)

Luza, MF

;

Bazan, RR

We define the polar curves and the polar family associated to a projective web and obtain some results about the geometry of the generic element of this family. We also deal with the particular case of foliations and prove the constancy of the topological embedded type of the generic polar.

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