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Landscape and micronutrient fertilizer effect on agro-fortified wheat and teff grain nutrient concentration in western Amhara

Tilahun Amede Elizabeth Bailey Abdul Wahab Mossa Dereje Tirfessa MESFIN KEBEDE DESTA Getachew Agegnehu Tesfaye Shiferaw Sida Stephan Haefele R. Murray Lark Martin Broadley Samuel Gameda (2023, [Artículo])

Agronomic biofortification, encompassing the use of mineral and organic nutrient resources which improve micronutrient concentrations in staple crops is a potential strategy to promote the production of and access to micronutrient-dense foods at the farm level. However, the heterogeneity of smallholder farming landscapes presents challenges on implementing agronomic biofortification. Here, we test the effects of zinc (Zn)- and selenium (Se)-containing fertilizer on micronutrient concentrations of wheat (Triticum aestivum L.) and teff (Eragrostis tef (Zucc.) Trotter) grown under different landscape positions and with different micronutrient fertilizer application methods in the western Amhara region of Ethiopia. Field experiments were established in three landscape positions at three sites, with five treatments falling into three broad categories: (1) nitrogen (N) fertilizer rate; (2) micronutrient fertilizer application method; (3) sole or co-application of Zn and Se fertilizer. Treatments were replicated across five farms per landscape position and over two cropping seasons (2018 and 2019). Grain Zn concentration ranged from 26.6 to 36.4 mg kg−1 in wheat and 28.5–31.2 mg kg−1 in teff. Grain Se concentration ranged from 0.02 to 0.59 mg kg−1 in wheat while larger concentrations of between 1.01 and 1.55 mg kg−1 were attained in teff. Larger concentrations of Zn and Se were consistently attained when a foliar fertilizer was applied. Application of ⅓ nitrogen (N) yielded significantly larger grain Se concentration in wheat compared to a recommended N application rate. A moderate landscape effect on grain Zn concentration was observed in wheat but not in teff. In contrast, strong evidence of a landscape effect was observed for wheat and teff grain Se concentration. There was no evidence for any interaction of the treatment contrasts with landscape position except in teff, where an interaction effect between landscape position and Se application was observed. Our findings indicate an effect of Zn, Se, N, landscape position, and its interaction effect with Se on grain micronutrient concentrations. Agronomic biofortification of wheat and teff with micronutrient fertilizers is influenced by landscape position, the micronutrient fertilizer application method and N fertilizer management. The complexity of smallholder environmental settings and different farmer socio-economic opportunities calls for the optimization of nutritional agronomy landscape trials. Targeted application of micronutrient fertilizers across a landscape gradient is therefore required in ongoing agronomic biofortification interventions, in addition to the micronutrient fertilizer application method and the N fertilizer management strategy.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA BIOFORTIFICATION LANDSCAPE SELENIUM ZINC WHEAT

Corrección de defectos óseos en el área de Ingeniería tisular

Correction of bone defects by tissue Engineering

ROSA ALICIA SAUCEDO ACUÑA MONICA GALICIA GARCIA JUDITH VIRGINIA RIOS ARANA SIMON YOBANNY REYES LOPEZ (2012, [Artículo])

Hoy en día, los defectos óseos representan uno de los casos de mayor impacto en la salud debido a la frecuencia con que éstos ocurren a causa de traumatismos, fracturas, enfermedades congénitas o degenerativas. En la actualidad, los implantes de tejido óseo de gran volumen se encuentran severamente restringidos a causa de las limitaciones de difusión en la interacción con el ambiente del huésped para los nutrientes, intercambio gaseoso y eliminación de desechos. Es por ello que la corrección de los defectos óseos ha cobrado gran importancia en el área de Ingeniería tisular buscando mejorar las estrategias clínicas para su tratamiento. El propósito de esta revisión es proporcionar un panorama general del desarrollo de andamios para la regeneración de tejido óseo, mostrando los avances logrados en los ensayos in vitro e in vivo en la última década

Currently, bone defects cases represent a major impact on health due to how often they occur because of trauma, fractures, congenital or degenerative diseases. Now, bone implants to large volume are severely restricted because of the diffusion limitations in the interaction

with the environment of the host for nutrients, gas exchange and waste disposal. That is why the correction of bone defects has become very important in the field of tissue engineering looking to improve clinical strategies for treatment. The purpose of this review is to provide an overview of the development of scaffolds for bone tissue regeneration, showing the progress made in the in vitro and in vivo in recent decades.

MEDICINA Y CIENCIAS DE LA SALUD Ingeniería tisular regeneración ósea Andamio Tissue engineering Bone regeneration Scaffolds

Do provisioning ecosystem services change along gradients of increasing agricultural production?

Ronju Ahammad Stephanie Tomscha Sarah Gergel Frédéric Baudron Jean-Yves Duriaux Chavarría Samson Foli Dominic Rowland Josh Van Vianen Terence Sunderland (2024, [Artículo])

Context: Increasing agricultural production shapes the flow of ecosystem services (ES), including provisioning services that support the livelihoods and nutrition of people in tropical developing countries. Although our broad understanding of the social-ecological consequences of agricultural intensification is growing, how it impacts provisioning ES is still unknown. Objectives: We examined the household use of provisioning ES across a gradient of increasing agricultural production in seven tropical countries (Bangladesh, Burkina Faso, Cameroon, Ethiopia, Indonesia, Nicaragua and Zambia). We answered two overarching questions: (1) does the use of provisioning ES differ along gradients of agriculture production ranging from zones of subsistence to moderate and to high agriculture production? and (2) are there synergies and/or trade-offs within and among groups of ES within these zones? Methods: Using structured surveys, we asked 1900 households about their assets, livestock, crops, and collection of forest products. These questions allowed us to assess the number of provisioning ES households used, and whether the ES used are functionally substitutable (i.e., used similarly for nutrition, material, and energy). Finally, we explored synergies and trade-offs among household use of provisioning ES. Results: As agricultural production increased, provisioning ES declined both in total number and in different functional groups used. We found more severe decreases in ES for relatively poorer households. Within the functional groups of ES, synergistic relationships were more often found than trade-offs in all zones, including significant synergies among livestock products (dairy, eggs, meat) and fruits. Conclusions: Considering landscape context provides opportunities to enhance synergies among provisioning services for households, supporting resilient food systems and human well-being.

Agricultural Production Zones Agricultural Intensifcation Synergies and Trade-Offs Landscape Multifunctionality Social-Ecological Systems CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGRICULTURE INTENSIFICATION ECOSYSTEM SERVICES LANDSCAPE SOCIAL-ECOLOGICAL RESILIENCE ECOSYSTEM SERVICES

A pre-pandemic study about recreational uses in the Mexico Park located at Mexico City (year 2017)

Ramiro Flores-Xolocotzi Sergio Ceballos (2022, [Artículo, Artículo])

A recreational study was carried out through surveys in the Parque México in Mexico City. For this, the relationship between visit patterns with socioeconomic information, uses and perceptions of visitors with 18 years old or older was analyzed. This research uses descriptive statistics and a non-linear canonical correlation analysis to analyze relationships between variables. An ordered probit regression was also performed to determine the variables that explain the frequency of recreational use. It was obtained that the Park mainly receives visitors with at least bachelor's degree (78.6%) and high incomes (more than 50% have a monthly family income higher than $10,000.00 pesos and 27.6% receive more than $30,000.00 per month). Considering the results, the conclusions are that although the highest percentage of the studied population comes from neighborhoods outside the Roma-Condesa Corridor: then the visitors who live in the Corridor and who have higher incomes, have weight in the description of the model. The results allow to conclude too, that higher income increases the frequency of use. It is also observed that the park is used during the Monday to Friday by more than 50% of the population of visitors and with a high percentage of use in the mornings.

urban forestry urban planning leisure green areas correlación canónica no lineal parque urbano probit recreación CIENCIAS SOCIALES CIENCIAS SOCIALES

Diluted density. Urban planning in the Monterrey Metropolitan Area

Sheila Ferniza Quiroz Jesús Manuel Fitch Osuna (2021, [Artículo, Artículo])

The Monterrey Metropolitan Area (mma) in Northern Mexico has had an expansive and dispersed growth in recent decades. In 35 years, the city doubled its population and grew 8 times in territory (Secretariat for Sustainable Development, 2020). As a mitigation measure and with the objective of repopulating the areas within the city, urban regulations have been promoted that allow higher density and building potentials in some municipalities; however, the efforts are isolated and without metropolitan coordination. What are the urban regulation guidelines in the municipalities of the mma? How dense are its municipalities? Where are located the densest areas of the city? The objective of this research is to establish the current state of local regulation regarding urban development and to map the housing density to identify the locations with the lowest and highest density at the mma. The gross density at the Ageb scale is mapped for the 18 municipalities of the mma through the QGis software; data from the Inegi 2020 National Population and Housing Census is used. It is found that the peripheral municipalities of recent incorporation to the mma, unlike those of greater urbanization, lack urban development plans, and that most of the municipalities do not have updated regulations based on the current laws. The areas with the highest density are located in the peripheral municipalities, associated with the construction of low-income mass housing, and those with the lowest density in interior municipalities in areas of higher socioeconomic status, diluting the small efforts of densification in the city.

density urban sprawl urban planning densidad expansión urbana planeación urbana HUMANIDADES Y CIENCIAS DE LA CONDUCTA HUMANIDADES Y CIENCIAS DE LA CONDUCTA

Un Fantasma recorre el mundo: El fantasma de las privatizaciones. Balance del cambio y continuidad en las asociaciones publico-privadas bajo el gobierno de izquierda de México(2018-2021)

MARIELA DIAZ SANDOVAL ALBERTO ESPEJEL ESPINOZA (2021, [Capítulo de libro])

The purpose of this article is to analyze the politics around privatizations in the left-wing government of Andrés Manuel López Obrador (Amlo). The aim is to identify the ideational mark and the possible breaks or continuities of the infrastructure policy in a global context characterized by the promotion of the Public-Private Parnerships (ppps) -as a modality of the privatization of public goods and services-. It is argued that the ideas around the State in the current administration do not approve the participation of the private sector in the prison, and hospital sectors, freezing, to some extent, the privatization inertia promoted since the 1980s. We concluded that despite its open opposition, the Amlo government has had to use ppps in sectors such as road, energy infraestructure, and transport, due to budget restrictions that will be aggravated by the Covid-19 pandemic.

Andrés Manuel López Obrador (Amlo) public-private parnerships ideas partisian potilitics privatizations CIENCIAS SOCIALES CIENCIA POLÍTICA ADMINISTRACIÓN PÚBLICA OTRAS

Del urbanismo normativo al urbanismo dibujado. El plano de ensanche de Bogotá Futuro, 1925

Luis Carlos Colon Llamas Anthony Picón Rodríguez (2023, [Capítulo de libro])

Universidad Autónoma Metropolitana (México). Unidad Azcapotzalco. División de Ciencias y Artes para el Diseño. Departamento de Evaluación del Diseño en el Tiempo. Área de Estudios Urbanos.

En lo que sigue nos proponemos ver cuáles fueron las consecuencias del paso del urbanismo normativo al urbanismo dibujado. Para ello, en una primera parte, describiremos cuáles fueron las condiciones de producción del plano basados en dos fuentes: una de las dos copias conocidas de éste y la memoria que lo explica. En la segunda parte haremos un análisis de los principales elementos de la propuesta con el propósito de explicar la codificación de la ciudad futura que se proponía. En la parte final discutiremos cuáles fueron las principales consecuencias para la planeación, de la introducción de este nuevo instrumento en el contexto histórico de la Bogotá del momento.

Cartography--Colombia--History. City planning--Colombia--Bogotá--History. Cartografía -- Historia. Urbanismo. G1731.S1 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS ARQUITECTURA URBANISMO