Dual-polarization reflectarray in Ku-band based on two layers of dipole arrays for a transmit–receive satellite antenna with South American coverage

A 1.1-m reflectarray antenna has been designed, manufactured and tested to fulfil the requirements of a satellite antenna in Ku-band that provides South American coverage in Tx and Rx. The reflectarray cells consist of four dipoles for each polarization in two dielectric layers, selected because of their simplicity and high performance. The dipole dimensions are optimized in all the reflectarray cells to accomplish the prescribed radiation patterns, by iteratively calling an analysis routine based on method of moments in spectral domain and local periodicity. The measured radiation patterns of the manufactured antenna have been satisfactorily compared with simulations and with a 3-layer reflectarray previously designed, manufactured and tested for the same mission

MEXICAN WILD LUPINES AS A SOURCE OF QUINOLIZIDINE ALKALOIDS OF ECONOMIC POTENTIAL

Quinolizidine alkaloids such as lupanine,13-hydroxylupanine, multiflorine, angustifoline and sparteine, which are present inthe species of the genus Lupinus, have beenreported to have biopesticide and pharmacological activities. The aim of this studywas to quantify the content and variationof the individual alkaloids in seeds of L.mexicanus, L. exaltatus, L. montanus andL. stipulatus collected in different states ofMexico. Lupanine was the major (5.05 ±0.37 mg/g) alkaloid found in L. mexicanus,whereas sparteine was the main alkaloidpresent in L. montanus (3.97 ± 0.49 mg/g).Conversely, L. stipulatus contained onlysmall quantities of lupanine and sparteine(0.1 ± 0.002 and 0.04 ± 0.01 mg/g, respectively). Angustifoline was detected only in L.montanus, but in a very low amount (0.048± 0.03). The results of this study indicatethat L. mexicanus and L. montanus can beconsidered as important sources of lupanine and sparteine for their use as natural pesticide or pharmacological agents.Los alcaloides quinolizidinicos lupanina,13-hidroxilupanina, multiflorina, angustifolina y esparteina, presentes en el géneroLupinus poseen actividades bioplagiciday farmacológica. El objetivo del presenteestudio fue cuantificar el contenido y variación de los alcaloides mencionados ensemillas de L. mexicanus, L. exaltatus, L.montanus y L. stipulatus, colectados endiferentes estados de México. La lupaninafue el principal (5.05 ± 0.37mg /g) alcaloideencontrado en L. mexicanus, mientras que laesparteína fue el mayor alcaloide presente en L. montanus (3.97 ± 0.49 mg/g). Sinembargo, en L. stipulatus se encontraron pequeñas cantidades de lupanina y esparteína(0.1 ± 0.002 y 0.04 ± 0.01 mg/g, respectivamente). La angustifolina sólo se detectóen bajos niveles en L. montanus (0.048 ±0.03). Los resultados de este estudio indicanque L. mexicanus y L. montanus pueden serconsiderados como una fuente importantede lupanina y esparteína, los cuales puedenser utilizados como pesticidas o hipoglucé-micos naturales

Aplicación de dos métodos de clasificación nomenclatural del complemento cromosómico de dos especies de Gossypium

Aplicación de dos métodos de clasificación nomenclatural del complemento cromosómico de dos especies de GossypiumHERNÁN E.FERRER-PEREIRA, JESÚS R. MÉNDEZ-NATERA & NILDA C.Application of two methods of nomenclature classification of chromosomal complement of two Gossypium species</htm

Karyotypic Assymmetries observed in two species of Gossypium L.

Karyotypic Assymmetries observed in two species  of  Asimetrías cariotípicas observadas en dos especies de Gossypium L. </htm

The use of activity diaries for understanding the daily lives of farmers and their livelihood choices

This paper reviews the use of activity diaries in two Australian Centre for International Agricultural Research (ACIAR) projects in PNG: a smallholder cocoa project in the East New Britain province (ASEM/2006/127) and a smallholder coffee project in Eastern Highlands province (ASEM/2008/036). Both projects were similarly concerned with identifying the production constraints on cocoa- and coffee-farming households and to better understand the range of socioeconomic and cultural factors influencing farmer decision-making and the allocation of household labour among various livelihood activities. In PNG, the household is the principal production unit underpinning livelihood activities such as commodity production. It is at the household level that decisions and negotiations are made regarding the organisation, mobilisation and management of family and extended family labour. Thus, examining in detail the daily economic and social livelihood activities of household members, through time-allocation studies, helps researchers to understand more comprehensively the factors influencing smallholder decision-making regarding livelihood choices, agricultural practices and the adoption of agricultural innovations. This paper outlines two different techniques using activity diaries employed in the projects, and discusses the methodological advantages and challenges of these techniques in smallholder studies in PNG

Tamoxifen Is Effective in the Treatment of Leishmania amazonensis Infections in Mice

Leishmaniasis is an antropozoonotic disease with a wide range of clinical manifestations. In humans, signs of disease vary from skin and mucosal ulcers to enlargement of internal organs such as the liver and spleen. The unicellular parasite Leishmania amazonensis is able to infect humans and cause localized or diffuse skin lesions. The treatment for this disease is difficult, as it requires prolonged and painful applications of toxic drugs that are poorly tolerated. Therefore, a key area in leishmaniasis research is the study of new therapeutic schemes and less toxic drugs. The present report is based on the investigation of tamoxifen's activity (a compound that has been in clinical use since the 1970s for the treatment of breast cancer) in the treatment of mice experimentally infected with L. amazonensis. We observed that infected mice treated with 20 mg/kg/day of tamoxifen for 15 days showed a significant clinical and parasitological response, with reduction in the size of lesions and ulcers and decreased numbers of parasites. These promising results pave the way for further testing of this drug as a new alternative in the chemotherapy of leishmaniasis

Pathological Features in Paediatric Patients with TK2 Deficiency

Thymidine kinase (TK2) deficiency causes mitochondrial DNA depletion syndrome. We aimed to report the clinical, biochemical, genetic, histopathological, and ultrastructural features of a cohort of paediatric patients with TK2 deficiency. Mitochondrial DNA was isolated from muscle biopsies to assess depletions and deletions. The TK2 genes were sequenced using Sanger sequencing from genomic DNA. All muscle biopsies presented ragged red fibres (RRFs), and the prevalence was greater in younger ages, along with an increase in succinate dehydrogenase (SDH) activity and cytochrome c oxidase (COX)-negative fibres. An endomysial inflammatory infiltrate was observed in younger patients and was accompanied by an overexpression of major histocompatibility complex type I (MHC I). The immunofluorescence study for complex I and IV showed a greater number of fibres than those that were visualized by COX staining. In the ultrastructural analysis, we found three major types of mitochondrial alterations, consisting of concentrically arranged lamellar cristae, electrodense granules, and intramitochondrial vacuoles. The pathological features in the muscle showed substantial differences in the youngest patients when compared with those that had a later onset of the disease. Additional ultrastructural features are described in the muscle biopsy, such as sarcomeric de-structuration in the youngest patients with a more severe phenotype