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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

Habitability conditions for floods: the case of Tuxtla Gutiérrez, Chiapas, Mexico

MARCELINO GARCIA BENITEZ Saul Nucamendi Hernandez Omar Ávila Flores (2022, [Artículo, Artículo])

At present, there are changes in the environment that favor the presence of extreme climatic phenomena such as floods, this exposure implies that the populations of urban areas suffer effects on their material assets, which limits their capacity for individual and / or family development. Given the lack of local territorial planning, the establishment of colonies was allowed on the banks of the Sabinal river and its tributaries that present episodes of flooding during the rainy season (Sistema Municipal de Protección Civil, 2015).

 

The study evaluates the habitability conditions of the urban population exposed to flooding, the city of Tuxtla Gutiérrez, Chiapas is taken as a reference, since historically it is a recurring problem during the summer. The methodology interrelates geostatistical, spatial and cartographic databases with hemerographic information sources based on the review of the literature for the construction of the general index, determined in dimensions that group social, economic, educational aspects, availability of basic services, goods with those that count the dwellings and their accessibility, etc., on a geographical scale of Urban Geostatistical Areas (AGEB).

 

The results obtained generated an index on the distribution of habitability conditions by urban Ageb, they are interrelated with spatial data on floods and their relationship with Sustainable Development Goal 11 (ODS), which proposes to improve infrastructure conditions in cities and towns. sustainable communities so that the inequality originated among the population exposed to future extreme flood events that occur in the different areas that make up the city is reduced.

Habitability conditions floods Sustainable Development Goals urban Ageb city of Tuxtla Gutiérrez, Chiapas AGEB urbana ciudad de Tuxtla Gutiérrez, Chiapas condiciones de habitabilidad inundaciones CIENCIAS SOCIALES CIENCIAS SOCIALES

Supervivencia de Artemia franciscana en cocultivo con Vibrio campbellii y Nitzschia thermalis f. kurta

Survival of Artemia franciscana in coculture with Vibrio campbellii and Nitzschia thermalis f. kurta

Dalia Azucena Verde Inzunza (2023, [Tesis de maestría])

La acuicultura es uno de los sectores más importantes y de mayor producción alimentaria. Sin embargo, se ve afectada por enfermedades bacterianas como la vibriosis, la cual puede ocasionar pérdidas totales en los cultivos. El método más utilizado para controlar la vibriosis es el uso de antibióticos, lo cual ha contribuido al desarrollo de cepas bacterianas resistentes. Por ello, se buscan medios de control naturales para inhibir el crecimiento de Vibrio, como el uso de aguas verdes. El objetivo de este trabajo fue evaluar el efecto inhibitorio de Nitzschia thermalis f. kurta en la concentración de V. campbellii y en la supervivencia de nauplios de Artemia franciscana al estar en cocultivo. Se realizó un bioensayo de inhibición de V. campbellii en cocultivo con N. thermalis y nauplios de A. franciscana. Se mantuvieron cultivos monoespecíficos, no axénicos y por triplicado en medio “f” con una densidad celular de 250,000 cél. mL-1 de N. thermalis. Los cultivos fueron inoculados con una concentración inicial de 1 x105 V. campbellii mL-1 y una densidad de 1 nauplio de A. franciscana mL-1. Para cada tratamiento se evaluó la densidad celular de N. thermalis, conteo de bacterias heterotróficas, cuantificación de la concentración de V. campbellii y la supervivencia de nauplios de A. franciscana durante 5 días. Se obtuvo una supervivencia promedio de 55% de nauplios de A. franciscana al estar en cocultivo con N. thermalis. Mientras que el tratamiento control sin la presencia de N. thermalis obtuvo una supervivencia de nauplios de A. franciscana del 0%. El contenido de bacterias heterotróficas se presentó en todos los tratamientos en un orden de magnitud de 106 UFC mL-1, lo cual nos indica que el efecto inhibitorio de N. thermalis es específico para V. campbellii. La concentración de V. campbellii disminuyó a 53 V. campbellii mL-1 al día 5 en el cocultivo de V. campbellii con N. thermalis y nauplios de A. franciscana. Se concluye que N. thermalis tiene un efecto inhibitorio contra V. campbellii y brinda protección a los nauplios de A. franciscana en cocultivo con V. campbellii.

Aquaculture is one of the most important sectors with the highest food production. However, it is affected by bacterial diseases such as vibriosis, which can cause total crop losses. The most used method to control vibriosis is antibiotics, which have contributed to the developing of resistant bacterial strains. For this reason, natural control means are sought to inhibit Vibrio growth, such as using green water. This work aimed to evaluate the inhibitory effect of Nitzschia thermalis f. kurta in the concentration of V. campbellii and the survival of Artemia franciscana nauplii when in coculture. An inhibition bioassay of V. campbellii was carried out in coculture with N. thermalis and nauplii of A. franciscana. Monospecific, non-axenic cultures were maintained in triplicate in “f” medium with a cell density of 250,000 cells mL-1 of N. thermalis. The cultures were inoculated with an initial concentration of 1 x105 V. campbellii mL-1 and a density of 1 nauplius of A. franciscana mL-1. For each treatment, the cell density of N. thermalis, count of heterotrophic bacteria, quantification of the concentration of V. campbellii, and the survival of A. franciscana nauplii were evaluated for 5 days. Was obtained an average survival of 55% of A. franciscana nauplii when cocultured with N. thermalis. In contrast, the control treatment without the presence of N. thermalis obtained a survival of A. franciscana nauplii of 0%. The content of heterotrophic bacteria was present in all treatments in order of magnitude of 106 CFU mL-1, which indicates that the inhibitory effect of N. thermalis is specific to V. campbellii. The concentration of V. campbellii decreased to 53 V. campbellii mL-1 on day 5 in the co-culture of V. campbellii with N. thermalis and A. franciscana nauplii. It is concluded that N. thermalis has an inhibitory effect against V. campbellii and provides protection to A. franciscana nauplii in coculture with V. campbellii.

Artemia franciscana, Vibrio campbellii, inhibición, Nitzschia thermalis Artemia franciscana, Vibrio campbellii, inhibition, Nitzschia thermalis CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE PISCICULTURA PISCICULTURA

Desarrollo de nanocompositos de cápside viral P22 para la terapia con profármacos enzimáticos en cáncer de mama

Development of P22 viral capsid nanocomposites for enzymatic prodrug therapy in breast cancer

Astrid Rebeca Luna Rios (2024, [Tesis de maestría])

Las estrategias actuales contra el cáncer de mama presentan limitaciones debido a la falta de selectividad, disminuyendo su efectividad. La mayoría de los fármacos, como el tamoxifeno, requieren la activación metabólica por parte de las enzimas de la familia citocromo P450 (CYP) para ejercer mayores efectos anticancerígenos. Sin embargo, la concentración del CYP es variable y baja en las células tumorales, especialmente en el cáncer de mama, lo que provoca efectos secundarios. En la terapia de activación enzimática de profármacos (EPT), las enzimas se dirigen al tumor para transformar el profármaco, lo que normalmente implica la administración de la enzima seguida del profármaco. Sin embargo, las diferencias entre la farmacocinética y farmacodinamia son un obstáculo para mejorar el tratamiento. Por lo tanto, la administración conjunta de profármaco y enzima es esencial para garantizar su interacción favorable en el tumor. Este trabajo reporta una nueva clase de nanocompositos terapéuticos basados en partículas tipo virus P22 confinando CYP, funcionalizadas superficialmente con glucosa oxidasa (GOx) que transforma la glucosa en D-glucono-δ-lactona produciendo H2O2, el aceptor final de electrones en la transformación de tamoxifeno mediado por CYP, y conjugadas con un derivado de tamoxifeno como profármaco y ligando dirigido utilizando polietilenglicol como conector. En un microambiente tumoral rico en glucosa, estos nanocompuestos pueden producir fármaco activo in situ. Se caracterizaron las propiedades fisicoquímicas y la catálisis secuencial mediada por glucosa de los nanocompositos. Los estudios in vitro demostraron una disminución en la viabilidad celular en líneas celulares de cáncer de mama ER+ y ER-. Sin embargo, la internalización celular en ausencia de glucosa mostró ser preferencial con las VLPs dirigidas en ambas líneas celulares. La administración conjunta de enzimas y profármacos con una localización mejorada de las VLPs desarrolladas después de la funcionalización del tamoxifeno, lo que sugiere el potencial de los nanocompositos desarrollados para superar los desafíos existentes de la EPT y mejorar los resultados terapéuticos con efectos secundarios reducidos.

Current treatment strategies against breast cancer have limitations due to lack in selectivity. Most drugs, such as tamoxifen, require metabolic activation by cytochrome P450 (CYP) enzymes to perform greater anticancer effects. However, the concentration of CYP varies and is low in tumor cells, especially in breast cancer, resulting in side-effects. In enzyme prodrug therapy (EPT), enzymes are targeted to the tumor cells for prodrug transformation, typically involving the sequential delivery of the enzyme followed by the prodrug. However, differences in pharmacokinetics and pharmacodynamics are a major hindrance for improving treatment. Therefore, co-delivery of prodrug and enzyme is essential to ensure their favorable interaction in tumor. This work reports a new class of therapeutic nanocomposites based on P22 virus like particles (VLPs) confining the CYP activity, surface functionalized with glucose oxidase (GOx) that transforms glucose into D-glucono-δ-lactone producing hydrogen peroxide, the final electron acceptor in the CYP-mediated transformation of tamoxifen, and together conjugated with a tamoxifen derivative as prodrug and targeting ligand using polyethylene glycol as a linker. In glucose-rich tumor microenvironment, these nanocomposites can produce active drug in situ. The physicochemical properties and sequential glucose-mediated catalysis of the nanocomposites were characterized. In vitro studies demonstrated a decrease in cell viability in both ER+ and ER- breast cancer cell lines. However, cellular internalization in the absence of glucose showed improved uptake of targeted VLPs in both cell lines. The co-delivery of enzymes and prodrug with improved localization of developed VLPs after tamoxifen functionalization, suggests the potential of developed nanocomposites to overcome the existing challenges of EPT and improve the therapeutic outcomes with reduced side effects.

VLP-P22, Citocromo P45O, Glucosa oxidasa, Tamoxifeno, Terapia de activación enzimática de profármacos VLP-P22, Cytochrome P45O, Glucose oxidase, Tamoxifen, Enzyme prodrug therapy BIOLOGÍA Y QUÍMICA QUÍMICA QUÍMICA FARMACÉUTICA DISEÑO.SÍNTESIS Y ESTUDIO NUEVOS FÁRMACOS DISEÑO.SÍNTESIS Y ESTUDIO NUEVOS FÁRMACOS

Propuesta para estandarizar la técnica de aspiración de secreciones en pacientes con intubación orotraqueal

LIZBETH FITZ BELTRÁN (2023, [Otro, Trabajo terminal, especialidad])

La aspiración de secreciones es una técnica que realiza el personal de enfermería que consiste en

la extracción de secreciones traqueobronquiales con ayuda de un sistema de presión en pacientes

intubados Este procedimiento en este tipo de pacientes debe ser totalmente estéril y adecuado

antes, durante y después de la aspiración, ya que nuestro objetivo es proporcionar al paciente un

estado de bienestar y confort, mantener la permeabilidad de la vía aérea y un adecuado intercambio

gaseoso, estimular el reflejo tusígeno y evitar el desarrollo de una infección respiratoria debido al

acúmulo de secreciones.

El siguiente trabajo es un estudio de tipo cuantitativo con método observacional y de corte

transversal, se espera que el personal de enfermería de las áreas donde se encuentran pacientes con

intubación orotraqueal unifiquen conocimientos sobre la técnica de aspiración de secreciones con

una propuesta de capacitación sobre la técnica de aspiración de secreciones , se tomara una muestra

de conveniencia de 47 enfermeros de los servicios de UCIA A, sala de hombres, sala de mujeres

2 y urgencias . Se realizará la capacitación al personal de enfermería sobre la técnica de aspiración

de secreciones tanto sistema abierto como cerrado, esto ayudará al personal de enfermería a realizar

correctamente la técnica de aspiración de secreciones, ayudando tanto al paciente como a la

institución ya que se evitarán complicaciones hacia el paciente, así como, disminución en estancia

hospitalaria.

Secretion aspiration is a technique that nurses doing to extract tracheal secretion with the help of

pressure system in mecanical ventilation patientes. With this kind of patient, the secretion

aspiration procedure must be sterile technique before during and after, because our goal is get to

the patient a well-being state and confort, holding permeability on the airway and gas exchange

suitable, increased sputum expectoration and avoid respiratory tract infections.

This Study is an observational research with cross-sectional transverse design, with this protocole

hope that nurses that care these kind of patients, would homogen their knowledge abote secretion

aspiration technique, with a training program, about the correct secretion aspiration technique.

It will take a convenience sampling for 47 nurses in the adult intensive care unit, man united,

women unit 2 and emergency. It will be carried out, capacitation for nurses about secretion

aspiration technique, open system and close system, with the purpose to help nurses doing correctly

that technique. This action will benefit patients and decreasing their hospital stay.

MEDICINA Y CIENCIAS DE LA SALUD CIENCIAS MÉDICAS técnica, aspiración de secreciones, enfermería technique , aspiration of secretions, nurses.

Revitalización y renovación en las formas dramáticas. Algunos casos particulares

ALEJANDRO ORTIZ BULLÉ GOYRI (2019, [Artículo])

Artículo número 2 de la Sección Variaciones. 18 páginas. tyvlliii

En este artículo se establecen algunas consideraciones relacionadas con las transformaciones que en las últimas décadas ha tenido la literatura dramática en Hispanoamérica y particularmente en México. Se reflexiona acerca de los procesos de hibridación y de diversificación en los modelos de creación teatral, como es el caso de las interacciones entre narrativa y drama; así como las variables del llamado microteatro, y sus posibles vínculos con la tradición del poema breve y el haikú.

This article establishes some considerations related to the transformations that the dramatic literature in Hispanic America and particularly in Mexico has had in recent decades. It reflects on the processes of hybridization and diversification in models of theatrical creation, as is the case of the interactions between narrative and drama; as well as the variables of the so-called microtheatre, and its possible links with the tradition of the short poem and the haiku.

Teoría dramática, microteatro, hibridez, dramaturgia. Dramatic theorie, hibridity, microtheatre, dramaturgy. HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS TEORÍA, ANÁLISIS Y CRÍTICA LITERARIAS

Low thermal conductivity solar domestic water heater

MIGUEL ANGEL PORTA GANDARA JOSE LUIS FERNANDEZ ZAYAS JUAN FRANCISCO VILLA MEDINA NORBERTO CHARGOY DEL VALLE (2022, [Artículo])

"Solar domestic water heaters (SWH) with thermosyphon circulation are the most common commercial applications of solar energy in Mexico. They are also becoming popular in the rest of the world, given their simplicity, good economic returns, and sustainability. Traditionally the solar collector, the piping, and the storage tank are built of copper and steel. However, wáter quality in many parts of the Mexican Northwest has high mineral contents and, when heated, results in early metal pitting corrosion of SWH parts. Short-lived water heaters are bad promoters of the technology. In this work, a SWH thermoplastic Chlorinated Polyvinyl Chloride (CPVC) is built and tested under real operating conditions in La Paz, BCS, Mexico. The optimal design is detected with the aid of a suitable numerical model. Results reveal that a full SWH-CPVC can be technically and economically convenient for the weather conditions of the Northwestern states of Mexico."

Low thermal conductivity solar water heater CPVC solar water heater Solar water heater cooper pitting corrosion Thermosiphon circulation INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA ELECTRÓNICA DISPOSITIVOS TERMOELÉCTRICOS DISPOSITIVOS TERMOELÉCTRICOS