Leaf Anatomy and Ultrastructure of Poa Ligularis After Defoliation and Water Stress

The objective of this study was to determine the effect of defoliation and water stress on leaf anatomy and the mesophyll cell ultrastructure of Poa ligularis. Anatomical differences were detected mainly at epidermal level. Under water stress, leaf roughness was enhanced since the epidermal-cell surface contours became conspicuous. Under defoliation the microscopic roughness decreased as a result of fewer epicuticular wax crystals being formed. Defoliation produced an enhancement of the interlamellar spaces in the irrigated plantís chloroplast. Under no defoliation conditions, chloroplast structure was not affected by water stress. When subjected to water stress, lightly defoliated plants presented chloroplasts with a bellowed outer membrane, irregular thylacoid distribution and the disorganization of peripheral grana. Severely defoliated plants showed disorganized internal chloroplast membranes and even the disappearance of the grana. No breakdown or disappearance of chloroplast external membranes was detected under the imposed growing conditions, suggesting that no irreversible changes were induced

Long-term residue removal under tillage decreases amoA-nitrifiers and stimulates nirS-denitrifier groups in the soil

No-till in continuous corn (Zea mays L.) production helps to keep an important volume of residues on the soil surface, creating management challenges that could be alleviated by residue removal for bioenergy or animal use. Crop residues, however, are essential to stimulate microbial nutrient cycling in agroecosystems. Thus, both residue removal and tillage options need to be fully evaluated for their impacts on ecosystem services related to soil health, including microbial N cycling. We explored the main steps of the microbial N cycle in relation to soil properties by using targeted gene abundance as a proxy following over a decade of residue removal in continuous corn systems either under no-till or chisel tillage. We used real-time quantitative polymerase chain reaction (qPCR) for the quantification of phylogenetic groups and functional gene screening of the soil microbial communities, including genes encoding critical enzymes of the microbial N cycle: nifH (N2 fixation), amoA (nitrification – ammonia oxidation), nirK and nirS (denitrification – nitrite reduction), and nosZ (denitrification – nitrous oxide reduction). Our results showed that long-term residue removal and tillage decreased soil organic matter (SOM), water aggregate stability (WAS), and the relative abundance (RA) of ammonia-oxidizing bacteria (AOB) carrying nitrifying amoA genes. Denitrifiers carrying nirS genes decreased under no-till as crop residue was removed. In addition, our results evidenced strong correlations among soil properties and phylogenetic groups of bacteria, archaea, and fungi. Overall, this study demonstrated limited but definite impacts of residue management and tillage on the soil environment, which could be exacerbated under less resilient conditions.Fil: Kim, N.. University of Illinois; Estados UnidosFil: Riggins, C. W.. University of Illinois; Estados UnidosFil: Rodríguez Zas, S.. University of Illinois; Estados UnidosFil: Zabaloy, Maria Celina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Villamil, Maria Bonita. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. University of Illinois; Estados Unido

Acidification in corn monocultures favor fungi, ammonia oxidizing bacteria, and nirK-denitrifier groups

Agricultural practices of no-till and crop rotations are critical to counteract the detrimental effects of monocultures and tillage operations on ecosystem services related to soil health such as microbial N cycling. The present study explored the main steps of the microbial N cycle, using targeted gene abundance as a proxy, and concerning soil properties, following 19 and 20 years of crop monocultures and rotations of corn (Zea mays L.), and soybean [Glycine max (L.) Merr.], either under no-till or chisel tillage. Real-time quantitative polymerase chain reaction (qPCR) was implemented to estimate phylogenetic groups and functional genes related to the microbial N cycle: nifH (N2 fixation), amoA (nitrification) and nirK, nirS, and nosZ (denitrification). Our results indicate that long-term crop rotation and tillage decisions affect soil health as it relates to soil properties and microbial parameters. No-till management increased soil organic matter (SOM), decreased soil pH, and increased copy numbers of AOB (ammonia oxidizing bacteria). Crop rotations with more corn increased SOM, reduced soil pH, reduced AOA (ammonia oxidizing archaea) copy numbers, and increased AOB and fungal ITS copy numbers. NirK denitrifier groups were also enhanced under continuous corn. Altogether, the more corn years included in a crop rotation multiplies the amount of N needed to sustain yield levels, thereby intensifying the N cycle in these systems, potentially leading to acidification, enhanced bacterial nitrification, and creating an environment primed for N losses and increased N2O emissions.Fil: Behnke, G. D.. University of Illinois; Estados UnidosFil: Zabaloy, Maria Celina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Riggins, C. W.. University of Illinois; Estados UnidosFil: Rodríguez-Zas, S.. University of Illinois; Estados UnidosFil: Huang, L.. University of Illinois; Estados UnidosFil: Villamil, Maria Bonita. University of Illinois; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Records for the Glossy Ibis, Plegadis falcinellus (Linnaeus 1776), (Pelecaniformes: Threskiornithidae) in Colombia

In Colombia the Glossy Ibis (Plegadis falcinellus) has few records above 2000 m.a.s.l. We present a record of Glossy Ibis in the Fúquene Lagoon, Cundinamarca, Colombia, at 2600 m.a.s.l. which represents the first sighting of this bird in this wetland.En Colombia el ibis pico de hoz (Plegadis falcinellus) cuenta con pocos registros por encima de los 2000 m s.n.m. Se presenta un registro del ibis pico de hoz en la laguna de Fúquene, Cundinamarca, Colombia, a 2600 m s.n.m., el cual representa el primer avistamiento de esta ave en ese humedal

A Mobile ECG System for the Evaluation of Cardiovascular Risk

Problem: Cardiovascular diseases (CVD) are the number one cause of death globally. The World Health Organization estimated that 80% of the deaths caused by CVD take place in low and middle-income countries (LMIC). Objective: This paper describes the development of a mobile Electrocardiogram (ECG) system designed to support the evaluation of cardiovascular risk. Methods: The system was developed using low-cost technology, implemented under the open-source platform SANA and adding an ECG signal to the process of cardiovascular risk evaluation. Results: Main functionalities of the system include a visualization and analysis of the ECG signal in the Android mobile device, calculation of four cardiovascular risk scales, standard ECG transmission using the European Data Format (EDF), and integration into an Electronic Health Record system. Ten experts recommended 28 different application scenarios for the system, and evaluated its performance (100%) and relevance of the functionalities (89%). Conclusions: The paper demonstrates the feasibility to develop a low-cost, open source, mobile ECG System able to support the evaluation of cardiovascular risk and potentially useful for other health promotion and prevention programs and scenarios, especially in LMI

Poly(ADP-ribosylation) is present in murine sciatic nerve fibers and is altered in a Charcot-Marie-Tooth-1E neurodegenerative model

Background. Poly-ADP-ribose (PAR) is a polymer synthesized by poly-ADP-ribose polymerases (PARPs) as a postranslational protein modification and catabolized mainly by poly-ADP-ribose glycohydrolase (PARG). In spite of the existence of cytoplasmic PARPs and PARG, research has been focused on nuclear PARPs and PAR, demonstrating roles in the maintenance of chromatin architecture and the participation in DNA damage responses and transcriptional regulation. We have recently detected non-nuclear PAR structurally and functionally associated to the E-cadherin rich zonula adherens and the actin cytoskeleton of VERO epithelial cells. Myelinating Schwann cells (SC) are stabilized by E-cadherin rich autotypic adherens junctions (AJ). We wondered whether PAR would map to these regions. Besides, we have demonstrated an altered microfilament pattern in peripheral nerves of Trembler-J (Tr-J) model of CMT1-E. We hypothesized that cytoplasmic PAR would accompany such modified F-actin pattern. Methods. Wild-type (WT) and Tr-J mice sciatic nerves cryosections were subjected to immunohistofluorescence with anti-PAR antibodies (including antibody validation), F-actin detection with a phalloidin probe and DAPI/DNA counterstaining. Confocal image stacks were subjected to a colocalization highlighter and to semi-quantitative image analysis. Results. We have shown for the first time the presence of PAR in sciatic nerves. Cytoplasmic PAR colocalized with F-actin at non-compact myelin regions in WT nerves. Moreover, in Tr-J, cytoplasmic PAR was augmented in close correlation with actin. In addition, nuclear PAR was detected in WT SC and was moderately increased in Tr-J SC. Discussion. The presence of PAR associated to non-compact myelin regions (which constitute E-cadherin rich autotypic AJ /actin anchorage regions) and the co-alterations experienced by PAR and the actin cytoskeleton in epithelium and nerves, suggest that PAR may be a constitutive component of AJ /actin anchorage regions. Is PAR stabilizing the AJ -actin complexes? This question has strong implications in structural cell biology and cell signaling networks. Moreover, if PAR played a stabilizing role, such stabilization could participate in the physiological control of axonal branching. PARP and PAR alterations exist in several neurodegenerative pathologies including Alzheimer's, Parkinson's and Hungtington's diseases. Conversely, PARP inhibition decreases PAR and promotes neurite outgrowth in cortical neurons in vitro. Coherently, the PARP inhibitor XAV939 improves myelination in vitro, ex vivo and in vivo. Until now such results have been interpreted in terms of nuclear PARP activity. Our results indicate for the first time the presence of PARylation in peripheral nerve fibers, in a healthy environment. Besides, we have evidenced a PARylation increase in Tr-J, suggesting that the involvement of cytoplasmic PARPs and PARylation in normal and neurodegenerative conditions should be re-evaluated

The Effect of Conditional Cash Transfers on the Prepaid and Postpaid Expenditures of Internet and Cellular Services: The Case of Filipino Households

Technology has been playing a large role in the lives of households regardless of income. How, then, do poor families value the importance of internet and cellular services due to the existence of outcome-improving or outcome-worsening effects associated with these services? At the same time, since the Pantawid Pamilyang Pilipino Program (4Ps) substantially affects its beneficiaries’ household expenditures, assessing its effectiveness concerning its objectives is important. Most literature on how poor households spend their cash transfers is centered on directly linked goods such as health and education. However, the relationship between CCTs and expenditures on goods that play a more indirect yet increasing role in the lives of poor households (e.g., internet and cellular services) has yet to be explored. Using the 2018 Family Income and Expenditure Survey (FIES) with the 4Ps program serving as the treatment, a propensity score matching methodology is applied to compare beneficiaries’ expenditures on prepaid and postpaid internet and cellular services with non-beneficiaries via Average Treatment Effects on the Treated (ATT)

How Trade Liberalization and Labor Development Could Coincide in the Philippines

As the world adapts to the rapid pace of globalization in the 21st century, countries ease trade restrictions by gradually removing tariffs and non-tariff barriers to incentivize the free flow of goods across nations. This prevalence of trade liberalization policies propelled policymakers and economists to investigate the relationship between trade reforms and economic outcomes including wage inequality around the world. They found that trade liberalization, on average, has had a positive impact on economic growth, but prior studies that examine the effects of trade liberalization on wage inequality in developing countries have found mixed results. Recently, Murakami (2021) examined the impact of trade liberalization on wage inequality in Chile through the reduction in effective tariffs brought about by the regional trade agreements of the country. Following his empirical strategy, we examine the impact of trade liberalization on wage inequality in the Philippines. In this policy brief, we provide insights on our findings and policy recommendations that the Philippines can undertak