Drought-stress-induced up-regulation of CAM in seedlings of a tropical cactus, Opuntia elatior, operating predominantly in the C3 mode

Immediately after unfolding, cotyledons of the tropical platyopuntoid cactus, Opuntia elatior Mill., exhibited a C3-type diel CO2 exchange pattern characterized by net CO2 uptake in the light. Significant nocturnal increases in titratable acidity typical of crassulacean acid metabolism (CAM) were not detected at this early developmental stage. As cotyledons matured and the first cladode (flattened stem) developed, features of CAM were observed and the magnitude of CAM increased. Nonetheless, in well-watered seedlings up to 10 cm tall, C3 photosynthetic CO2 fixation in the light remained the major pathway of carbon fixation. Reduced soil water availability led to an up-regulation of net dark CO2 fixation and greater nocturnal increases in tissue acidity, consistent with facultative CAM. These observations demonstrate that C3 photosynthesis, drought-stress-related facultative CAM, and developmentally controlled constitutive CAM can all contribute to the early growth of O. elatior. The strong C3 component and facultative CAM features expressed in young O. elatior contrast with mature plants in which obligate CAM is the major pathway of carbon acquisition

Sistema de produção de leite à base de pastagens cultivada e nativa melhorada na região de Bagé.

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Nuevos datos sobre algunas especies de Hemeróbidos de la península Ibérica e islas Canarias, incluyendo una nueva especie invasora de origen neotropical en Portugal (Insecta, Neuroptera, Hemerobiidae)

New data on the distribution, biology and phenology of 25 brown lacewings species (Insecta, Neuroptera: Hemerobiidae) of Iberian and Canaries fauna are given. The species Hemerobius bolivari Banks, 1910, widely distributed in the Neotropical Region, is recorded for the first time in Europe as a new invasive species, from specimens collected on Thaumastocoris peregrinus Carpintero & Dellapé, 2006 (Hemiptera: Thaumastocoridae) colonies on Eucalyptus in Lisbon (Portugal). This brown lacewing species, along with Sympherobius gayi Navás, 1910, also known from South America, is the second invasive species of neotropical origin, belonging to this family, that is recorded in the Iberian Peninsula, both from Portugal. We also mention several species that have been seldom recorded in the Iberian Peninsula, and among them Wesmaelius ravus (Withycombe, 1923) is recorded for the second time in the Iberian Peninsula, now from Sierra Nevada (Granada). From samplings made in southern Spain (Malaga, Granada) Micromus angulatus (Stephens, 1836) shows activity as imagoes during winter time (the entire year in the Iberian Peninsula, including this area), and these data seem also to confirm its link to grass vegetation.Se anotan nuevos datos sobre la distribución, biología y fenología de 25 especies de hemeróbidos (Insecta, Neuroptera: Hemerobiidae) de las Faunas Ibérica y Canaria. La especie Hemerobius bolivari Banks, 1910, ampliamente distribuida por la Región Neotropical, se cita por primera vez de Europa como una nueva especie invasora, a partir de ejemplares recolectados en colonias de Thaumastocoris peregrinus Carpintero y Dellapé, 2006 (Hemiptera: Thaumastocoridae:) sobre Eucalyptus en Lisboa (Portugal). Esta especie, junto a Sympherobius gayi Navás, 1910, también originaria de Sudamérica, es la segunda especie invasora de origen neotropical que de esta familia se cita en la Península Ibérica, en este caso también de Portugal. Se mencionan varias especies que han sido muy escasamente citadas en la Península Ibérica, y entre ellas destaca Wesmaelius ravus (Withycombe, 1923), que se cita por segunda vez en la Península Ibérica, en este caso de Sierra Nevada (Granada). A partir de muestreos realizados en el sur de España (Málaga, Granada), se desprende actividad en los imagos de Micromus angulatus (Stephens, 1836) en los meses de invierno (a lo largo de todo el año en la Península Ibérica, incluyendo esta zona ibérica), y estos datos también parecen corroborar su vinculación con la vegetación arvense

Information and Networks (I&N) Program Review Panel : external review final report

The 2011-2016 period marks the implementation term of the IDRC’s Information and Networks (I&N) Program, which seeks to enable greater understanding of how information networks affect citizens in developing countries, especially those belonging to marginalized communities. This evaluation reports on coherence, effectiveness and appropriateness of the implementation of the I&N Program Prospectus. Focusing on the evolution of the program’s strategy and implementation, findings show that the I&N Program has been managed in line with what was envisaged. Priorities were established and changes made in a thoughtful manner, with convincing rationales provided where divergences occurred away from original intentions

Multi-level modeling of social factors and preterm delivery in Santiago de Chile

<p>Abstract</p> <p>Background</p> <p>Birth before the 37th week of gestation (preterm birth) is an important cause of infant and neonatal mortality, but has been little studied outside of wealthy nations. Chile is an urbanized Latin American nation classified as "middle-income" based on its annual income per capita of about $6000.</p> <p>Methods</p> <p>We studied the relations between maternal social status and neighborhood social status on risk of preterm delivery in this setting using multilevel regression analyses of vital statistics data linked to geocoded decennial census data. The analytic data set included 56,970 births from 2004 in the metropolitan region of Santiago, which constitutes about 70% of all births in the study area and about 25% of all births in Chile that year. Dimensionality of census data was reduced using principal components analysis, with regression scoring to create a single index of community socioeconomic advantage. This was modeled along with years of maternal education in order to predict preterm birth and preterm low birthweight.</p> <p>Results</p> <p>Births in Santiago displayed an advantaged pattern of preterm risk, with only 6.4% of births delivering before 37 weeks. Associations were observed between risk of outcomes and individual and neighborhood factors, but the magnitudes of these associations were much more modest than reported in North America.</p> <p>Conclusion</p> <p>While several potential explanations for this relatively flat social gradient might be considered, one possibility is that Chile's egalitarian approach to universal prenatal care may have reduced social inequalities in these reproductive outcomes.</p

Barley Ror1 encodes a class XI myosin required for mlo-based broad-spectrum resistance to the fungal powdery mildew pathogen

Loss-of-function alleles of plant MLO genes confer broad-spectrum resistance to powdery mildews in many eudicot and monocot species. Although barley (Hordeum vulgare) mlo mutants have been used in agriculture for more than 40 years, understanding of the molecular principles underlying this type of disease resistance remains fragmentary. Forward genetic screens in barley have revealed mutations in two Required for mlo resistance (Ror) genes that partially impair immunity conferred by mlo mutants. While Ror2 encodes a soluble N-ethylmaleimide-sensitive factor-attached protein receptor (SNARE), the identity of Ror1, located at the pericentromeric region of barley chromosome 1H, remained elusive. We report the identification of Ror1 based on combined barley genomic sequence information and transcriptomic data from ror1 mutant plants. Ror1 encodes the barley class XI myosin Myo11A (HORVU.MOREX.r3.1HG0046420). Single amino acid substitutions of this myosin, deduced from non-functional ror1 mutant alleles, map to the nucleotide-binding region and the interface between the relay-helix and the converter domain of the motor protein. Ror1 myosin accumulates transiently in the course of powdery mildew infection. Functional fluorophore-labeled Ror1 variants associate with mobile intracellular compartments that partially colocalize with peroxisomes. Single-cell expression of the Ror1 tail region causes a dominant-negative effect that phenocopies ror1 loss-of-function mutants. We define a myosin motor for the establishment of mlo-mediated resistance, suggesting that motor protein-driven intracellular transport processes are critical for extracellular immunity, possibly through the targeted transfer of antifungal and/or cell wall cargoes to pathogen contact sites

Bodyweight Perceptions among Texas Women: The Effects of Religion, Race/Ethnicity, and Citizenship Status

Despite previous work exploring linkages between religious participation and health, little research has looked at the role of religion in affecting bodyweight perceptions. Using the theoretical model developed by Levin et al. (Sociol Q 36(1):157–173, 1995) on the multidimensionality of religious participation, we develop several hypotheses and test them by using data from the 2004 Survey of Texas Adults. We estimate multinomial logistic regression models to determine the relative risk of women perceiving themselves as overweight. Results indicate that religious attendance lowers risk of women perceiving themselves as very overweight. Citizenship status was an important factor for Latinas, with noncitizens being less likely to see themselves as overweight. We also test interaction effects between religion and race. Religious attendance and prayer have a moderating effect among Latina non-citizens so that among these women, attendance and prayer intensify perceptions of feeling less overweight when compared to their white counterparts. Among African American women, the effect of increased church attendance leads to perceptions of being overweight. Prayer is also a correlate of overweight perceptions but only among African American women. We close with a discussion that highlights key implications from our findings, note study limitations, and several promising avenues for future research