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Modeling the growth, yield and N dynamics of wheat for decoding the tillage and nitrogen nexus in 8-years long-term conservation agriculture based maize-wheat system

C.M. Parihar Dipaka Ranjan Sena Prakash Chand Ghasal Shankar Lal Jat Yashpal Singh Saharawat Mahesh Gathala Upendra Singh Hari Sankar Nayak (2024, [Artículo])

Context: Agricultural field experiments are costly and time-consuming, and their site-specific nature limits their ability to capture spatial and temporal variability. This hinders the transfer of crop management information across different locations, impeding effective agricultural decision-making. Further, accurate estimates of the benefits and risks of alternative crop and nutrient management options are crucial for effective decision-making in agriculture. Objective: The objective of this study was to utilize the Crop Environment Resource Synthesis CERES-Wheat model to simulate crop growth, yield, and nitrogen dynamics in a long-term conservation agriculture (CA) based wheat system. The study aimed to calibrate the model using data from a field experiment conducted during the 2019-20-2020-21 growing seasons and evaluation it with independent data from the year 2021–22. Method: Crop simulation models, such as the Crop Environment Resource Synthesis CERES-Wheat (DSSAT v 4.8), may provide valuable insights into crop growth and nitrogen dynamics, enabling decision makers to understand and manage production risk more effectively. Therefore, the present study employed the CERES-Wheat (DSSAT v 4.8) model and calibrated it using field data, including plant phenological phases, leaf area index, aboveground biomass, and grain yield from the 2019-20-2020-21 growing seasons. An independent dataset from the year 2021–22 was used for model evaluation. The model was used to investigate the relationship between growing degree days (GDD), temperature, nitrate and ammonical concentration in soil, and nitrogen uptake by the crop. Additionally, the study explored the impact of contrasting tillage practices and fertilizer nitrogen management options on wheat yields. The experimental site is situated at ICAR-Indian Agricultural Research Institute (IARI), New Delhi, representing Indian Trans-Gangetic Plains Zone (28o 40’N latitude, 77o 11’E longitude and an altitude of 228 m above sea level). The treatments consist of four nitrogen management options, viz., N0 (zero nitrogen), N150 (150 kg N ha−1 through urea), GS (Green seeker based urea application) and USG (urea super granules @150 kg N ha−1) in two contrasting tillage systems, i.e., CA-based zero tillage (ZT) and conventional tillage (CT). Result: The outcomes exhibited favorable agreement between the model’s simulations and the observed data for crop phenology (With less than 2 days variation in 50% onset of flowering), grain and biomass yield (Root mean square error; RMSE 336 kg ha−1 and 649 kg ha−1, respectively), and leaf area index (LAI) (RMSE 0.28 & normalized RMSE; nRMSE 6.69%). The model effectively captured the nitrate-N (NO3−-N) dynamics in the soil profile, exhibiting a remarkable concordance with observed data, as evident from its low RMSE = 12.39 kg ha−1 and nRMSE = 13.69%. Moreover, as it successfully simulated the N balance in the production system, the nitrate leaching and ammonia volatilization pattern as described by the model are highly useful to understand these critical phenomena under both conventional tillage (CT) and CA-based Zero Tillage (ZT) treatments. Conclusion: The study concludes that the DSSAT-CERES-Wheat model has significant potential to assess the impacts of tillage and nitrogen management practices on crop growth, yield, and soil nitrogen dynamics in the western Indo-Gangetic Plains (IGP) region. By providing reliable forecasts within the growing season, this modeling approach can facilitate better planning and more efficient resource management. Future implications: The successful implementation of the DSSAT-CERES-Wheat model in this study highlights its applicability in assessing crop performance and soil dynamics. Future research should focus on expanding the model’s capabilities by reducing its sensitivity to initial soil nitrogen levels to refine its predictions further. Moreover, the model’s integration with decision support systems and real-time data can enhance its usefulness in aiding agricultural decision-making and supporting sustainable crop management practices.

Nitrogen Dynamics Mechanistic Crop Growth Models Crop Simulation CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA NITROGEN CONSERVATION AGRICULTURE WHEAT MAIZE CROP GROWTH RATE SIMULATION MODELS

Estrés académico en estudiantes de enfermería

KARLA VERONICA CASTILLO RÁBAGO (2023, [Tesis de maestría])

El estrés en los estudiantes de educación superior repercute a nivel físico,

emocional y psicológico de cada uno de estos, afectando su salud y rendimiento

académico. Objetivo: Analizar el nivel de estrés académico en los estudiantes de la

facultad de enfermería. Metodología: estudio cuantitativo, transversal,

observacional, analítico. Se utilizó el inventario SISCO, ya que permite identificar el estrés

en estudiantes de educación superior y posgrado. Se aplicó el inventario SISCO a 124

alumnos de primero al séptimo semestre del programa de licenciatura en

enfermería. Resultados: El nivel de estrés en el total de la población fue moderado

en un 58% y profundo en un 40%. El 95.16% manifestó momentos de preocupación

durante el semestre. El sexo femenino muestra mayores niveles de estrés. Los

estresores más frecuentes son los relacionados con las tareas y el tiempo (24%). El

uso de estrategias de afrontamiento es bajo (13.71%). Conclusiones: Los niveles

de estrés son elevados, pero podrían disminuir si los estudiantes utilizaran con

mayor frecuencia estrategias de afrontamiento del estrés de manera consciente.

Stress in higher education students affects the physical, emotional and psychological

level of each one of them, affecting their health and academic performance.

Objective: To analyze the level of academic stress in nursing students.

Methodology: quantitative, cross-sectional, observational, analytical study. The

SISCO inventory was applied to 124 students from the first to the seventh semester

of the nursing degree program. Results: The level of stress in the total population

was moderate in 58% and deep in 40%. 95.16% expressed moments of concern

during the semester. The female sex shows higher levels of stress. The most

frequent stressors are those related to tasks and time (24%). The use of coping

strategies is low (13.71%). Conclusions: Stress levels are high, but could decrease

if students consciously use stress coping strategies more frequently.

MEDICINA Y CIENCIAS DE LA SALUD CIENCIAS MÉDICAS nivel de estrés académico; estudiantes universitarios; estresores; síntomas; afrontamiento. academic stress level; University students; stressors; symptoms; coping.

Procesamiento emocional ante estímulos música-color y su respuesta electrofisiológica en personas con depresión

PABLO VALDÉS ALEMÁN (2024, [Tesis de maestría])

Dado el fenómeno del vínculo emocional que existe entre música y color, este

proyecto exploró los posibles efectos terapéuticos en personas con depresión, al

presentarles estímulos combinados de música con color que, en conjunto, evocan

emociones positivas y placenteras. El proyecto se dividió en tres partes, con el fin

de subsanar los vacíos en la literatura. Primero se evaluaron los 37 colores del

Berkeley Color Project como estímulos capaces de evocar emociones y placer,

distinguibles mediante los modelos de asimetría frontal de alfa (FAA) y de theta con

electroencefalografía (EEG). El segundo estudio exploró los posibles efectos

sinérgicos al combinar música y color de emoción congruente –i.e., misma

emoción–, mediante respuestas subjetivas y EEG. Por último, se probó el impacto

de estímulos música-color positivos y placenteros sobre el estado de ánimo de

personas con depresión, a partir de sus respuestas subjetivas y EEG. Se encontró

que los colores brillantes, alegres y placenteros se asocian con una mayor

activación –supresión de alfa– frontal izquierda, de acuerdo con el modelo de FAA.

En lugar de un efecto sinérgico, los hallazgos mostraron un predominio emocional

hacia la música, reafirmando su poder emocional por encima del color. Por último,

los resultados del tercer estudio demostraron una mejora en el estado de ánimo en

las personas con sintomatología depresiva tras la estimulación. Estos resultados

podrían informar a profesionales de la salud mental sobre nuevos métodos

terapéuticos para ayudar a pacientes con depresión, al conjuntar la musicoterapia

con la cromoterapia.

Given the phenomenon of the emotional link between music and color, this project

explored the possible therapeutic effects on people with depression by presenting

them with combined music-color stimuli that collectively evoke positive and pleasant

emotions. The project was divided into three parts to address gaps in the literature.

Firstly, the 37 colors from the Berkeley Color Project were evaluated as stimuli

capable of evoking emotions and pleasure, distinguishable through the frontal alpha

(FAA) and theta asymmetry models using electroencephalography (EEG). The

second study explored the potential synergic effects by combining music and color

of congruent emotion –i.e., the same emotion– using subjective responses and EEG.

Lastly, the impact of positive and pleasant music-color stimuli on the mood of

individuals with depression was tested based on their subjective responses and

EEG. It was found that bright, joyful, and pleasant colors are associated with

increased activation –alpha suppression– in the left frontal region of the scalp,

according to the FAA model. Instead of a synergic effect, the results showed an

emotional predominance towards music, reaffirming its emotional power over color.

Finally, the results of the third study demonstrated an improvement in the mood of

individuals with depressive symptoms following the stimulation. These findings could

inform mental health professionals about new therapeutic methods to assist patients

with depression by combining music therapy with chromotherapy.

MEDICINA Y CIENCIAS DE LA SALUD CIENCIAS MÉDICAS música, color y emoción; patrones de actividad EEG; Berkeley Color Project; musico-cromoterapia; depresión. music, color, and emotion; EEG activity patterns; Berkeley Color Project; music-chromotherapy; depression.

INFLUENCIA DE CONDICIONES AMBIENTALES SOBRE LA DISTRIBUCIÓN, ABUNDANCIA Y DESARROLLO DE LARVAS DE Totoaba macdonaldi (Gilbert, 1890), EN EL ALTO GOLFO DE CALIFORNIA

Marcelo Vidal Curiel Bernal (2023, [Tesis de doctorado])

"La presente tesis aborda una investigación sobre la biología, ecología y crecimiento de la Totoaba macdonaldi en el alto golfo de California. La totoaba, una especie endémica a esta región se encuentra actualmente en peligro de extinción debido a una serie de amenazas como: cambios en su ecosistema reproductivo y de crianza, pesca, incidental de juveniles e ilegal de adultos. Aunque en los últimos 30 años la población dio signos de recuperación, existen indicios de que tanto la población adulta como las abundancias de larvas presentan una tendencia decreciente. Lo que resalta la importancia de estudiar cómo la variabilidad ambiental incide en la distribución y abundancia de larvas de totoaba y subsecuentemente en el stock recluta de la especie. El estudio comienza con un análisis de la variabilidad del crecimiento individual en etapas juveniles y adultas de la totoaba. Para este propósito, se utiliza la varianza observada como elemento clave para parametrizar modelos de crecimiento individual. Los resultados indican que este enfoque proporciona estimaciones sólidas de los parámetros de crecimiento. A continuación, se investiga el crecimiento de las larvas de totoaba en condiciones de cultivo. Los datos revelan que un modelo sigmoideo describe mejor el crecimiento y se identifican dos puntos de inflexión en el crecimiento de las larvas. Estos hallazgos tienen importantes implicaciones para la cría y el cultivo de la totoaba para efectos de repoblación. Por último, se analiza la ecología y el transporte de las larvas de totoaba en el alto golfo de California. Se identifica una ventana óptima para el desove de la totoaba en términos de temperatura y concentración de clorofila, y se sugiere que las condiciones ambientales y la distribución de los adultos pueden influir en las abundancias de larvas en diferentes años. Además, se destaca la importancia del frente permanente al sur del alto golfo de California como una posible zona de acumulación de larvas como factor que contribuye al endemismo en la región. En conjunto, esta tesis representa un enfoque multidisciplinario para comprender los aspectos clave de la biología, ecología y crecimiento de la totoaba en el alto golfo de California. Los resultados proporcionan información valiosa para la conservación de esta especie amenazada y destacan la importancia de un enfoque integral en la gestión de los recursos marinos en esta región única."

"The following thesis addresses a research on the biology, ecology, and growth of Totoaba macdonaldi in the upper gulf of California. The totoaba, a fish species endemic to this region, is currently endangered due to a series of threats such as: changes in its reproductive and breeding ecosystem, juvenile bycatch, and illegal fishing. Although over the last 30 years, the population has shown signs of recovery, there are indications that both the adult population and larval abundances are on a declining trend. This underscores the importance of studying how environmental variability affects the distribution and abundance of totoaba larvae and subsequently the recruitment stock of the species. The study begins with an analysis of growth in juvenile and adult stages of the totoaba. For this purpose, observed variance is used to parameterize individual growth models. Results indicate that this approach provides robust estimates of growth parameters. Next, the growth of cultivated totoaba larvae is investigated. The data reveal that a sigmoid model better describes the growth in the early life stages of the totoaba, and two inflection points in larval growth are identified. These findings have important implications for the breeding and cultivation of the totoaba for restocking purposes. Finally, the ecology and transport of totoaba larvae in the upper gulf of California are analyzed. An optimal window for totoaba spawning in terms of temperature and chlorophyll concentration is identified, and it is suggested that environmental conditions and the distribution of adults may influence larval abundances in different years. Additionally, the importance of the permanent front to the south of the upper gulf of California is highlighted as a possible larval accumulation zone and a contributing factor to endemism in the region. Overall, this thesis represents a multidisciplinary approach to understanding key aspects of the biology, ecology, and growth of the totoaba in the upper gulf of California. The results provide valuable information for the conservation of this threatened species and underscore the importance of a comprehensive approach in the management of marine resources in this unique region."

Variabilidad ambiental, crecimiento, dispersión, rutas larvarias Environmental variability, growth, dispersion, larval routes CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE PROPAGACIÓN Y ORDENACIÓN PROPAGACIÓN Y ORDENACIÓN

Using Observed Residual Error Structure Yields the Best Estimates of Individual Growth Parameters

Marcelo Vidal Curiel Bernal EUGENIO ALBERTO ARAGON NORIEGA MIGUEL ANGEL CISNEROS MATA LAURA SANCHEZ VELASCO SYLVIA PATRICIA ADELHEID JIMENEZ ROSENBERG ALEJANDRO FRANCISCO PARES SIERRA (2021, [Artículo])

"Obtaining the best possible estimates of individual growth parameters is essential in studies of physiology, fisheries management, and conservation of natural resources since growth is a key component of population dynamics. In the present work, we use data of an endangered fish species to demonstrate the importance of selecting the right data error structure when fitting growth models in multimodel inference. The totoaba (Totoaba macdonaldi) is a fish species endemic to the Gulf of California increasingly studied in recent times due to a perceived threat of extinction. Previous works estimated individual growth using the von Bertalanffy model assuming a constant variance of length-at-age. Here, we reanalyze the same data under five different variance assumptions to fit the von Bertalanffy and Gompertz models. We found consistent significant differences between the constant and nonconstant error structure scenarios and provide an example of the consequences using the growth performance index _0 to show how using the wrong error structure can produce growth parameter values that can lead to biased conclusions. Based on these results, for totoaba and other related species, we recommend using the observed error structure to obtain the individual growth parameters."

multimodel inference, error structure, totoaba, growth performance BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) FISIOLOGÍA ANIMAL FISIOLOGÍA ANIMAL

Recent advances on research of native prawn Macrobrachium americanum (Decapoda: Palaemonidae) with aquaculture and conservation purposes

Yuneisy Milagro Agüero Fernández MIRIAM VICTORIA MARTIN MANZO MARITZA LOURDES SOBERANES YEPIZ Marcelo Ulises García Guerrero Yuniel Méndez Martínez Luis Hector Hernandez Hernandez Laura S López Greco Edilmar Cortés Jacinto (2022, [Artículo])

"Where good management practices on aquaculture are mandatory. The economic and ecological importance of prawns of the Genus Macrobrachium cause an impact at a global level involving economic, academic and social aspects. Macrobrachium americanum appears as one of the genus species with high nutritional value and an economic demand in the national and international markets, as well as a vital income for fisherman and producers of this species. For researchers, it is a challenge to find solutions to culture and propose conservation measures for M. americanum with emphasis on development, nutrition and reproduction. Although there are scientific studies supporting the economic importance of this species, our knowledge about its cultivation, reproduction and conservation is limited. This paper summarizes the latest studies made in cooperation with M. americanum in research lead by the Centro de Investigaciones Biológicas del Noroeste, Mexico. After several years of continuous research, it is considered that those efforts have produced useful information for the sustainable exploitation, conservation and basic management practices of this species."

Freshwater ecosystem, growth rate, native prawn species, conservation, sustainable fishing BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) ECOLOGÍA ANIMAL ECOLOGÍA ANIMAL

PROPUESTA DE MANEJO DE LA PESQUERÍA EMERGENTE DE MERLUZA DEL PACÍFICO NORTE Merluccius productus EN EL GOLFO DE ULLOA, BAJA CALIFORNIA SUR

PABLO MORA ZAMACONA (2023, [Tesis de doctorado])

"La merluza del Pacífico Merluccius productus se distribuye desde Alaska hasta el sur de México, con una población particular descrita al sur de la península de Baja California conocida como merluza enana, de la que poco se sabe. Dicha población actualmente no es pescada comercialmente, por lo que representa un recurso con potencial de explotación. Las pesquerías potenciales y emergentes crean desafíos y oportunidades para los administradores pesqueros que necesitan tomar decisiones sobre cómo gestionar de forma sostenible una pesquería previa a su inicio. Este trabajo propone y analiza posibles medidas alternativas de gestión pesquera para esta potencial pesquería, bajo incertidumbre biológica y de mercado. Debido al desconocimiento de diversos aspectos de la biología del recurso primeramente se analizó el crecimiento individual del stock y posteriormente se realizó un análisis bioeconómico de la potencial pesquería.

Para el análisis del crecimiento individual se utilizó un total de 240 otolitos y datos de longitud patrón de 932 especímenes muestreados de mayo a diciembre de 2015. La formación anual de incrementos en los otolitos se verificó mediante la relación de incremento marginal y el análisis de borde. La edad se estimó a partir de recuentos de anillos en secciones sagitales de otolitos y el crecimiento se analizó mediante un enfoque de inferencia multimodelo. Se consideraron los modelos de crecimiento de von Bertalanffy (VBGM), VBGM generalizado, Gompertz, Logístico y Johnson, los cuales se ajustaron a conjuntos de datos de talla a la edad observados y retrocalculados agrupados por sexo. Según el criterio de información de Akaike, el VBGM generalizado fue el más apropiado para las hembras (L∞= 31.36 cm, k= 0.15 cm año-1), mientras que el VBGM proporcionó el mejor ajuste para los machos (L∞= 25.35 cm, k= 0.28 cm año-1).

El análisis bioeconómico de alternativas de manejo para una potencial pesquería de merluza enana indicó que una nueva pesquería de dicho stock podría ser biológicamente sostenible y económicamente rentable, bajo un conjunto de estrategias de gestión y reglas de control. Se recomienda un acceso limitado con bajo esfuerzo pesquero ya que resulta más redituable por barco y biológicamente precautorio, considerando la alta incertidumbre asociada con la explotación de una población virgen..."

"The Pacific hake Merluccius productus is distributed from Alaska to southern Mexico, with a particular population described south of the Baja California peninsula known as dwarf hake, about which little is known. This population is not currently commercially fished; hence it represents a resource with potential for exploitation. Potential and emerging fisheries create challenges and opportunities for fishery managers who need to make decisions about how to sustainably manage a fishery prior to its initiation. This work proposes and analyzes possible alternative fishery management measures for this potential fishery, under biological and market uncertainty. Due to the lack of knowledge of various aspects of the biology of the resource, the individual growth of the stock was first analyzed and subsequently a bioeconomic analysis of the potential fishery was carried out.

A total of 240 otoliths and standard-length data from 932 specimens sampled from May to December 2015 were used for the analysis of individual growth. The annual formation of otolith increments was verified using the marginal increment analysis and the edge analysis. Age was estimated from annuli counts in sagittal sections of otoliths and growth was analyzed using a multi-model inference approach. The von Bertalanffy growth models (VBGM), generalized VBGM, Gompertz, Logistic and Johnson growth models were considered, which were fitted to observed and back calculated length-at-age data sets grouped by sex. According to Akaike's information criterion, the generalized VBGM was the most appropriate for females (L∞= 31.36 cm, k= 0.15 cm year-1), while the VBGM provided the best fit for males (L∞= 25.35 cm, k= 0.28 cm year-1).

The bioeconomic analysis of management alternatives for a potential dwarf hake fishery indicated that a new fishery for said stock could be biologically sustainable and economically profitable, under a set of management strategies and control rules. Limited access with low fishing effort is recommended as it is more profitable by boat and biologically precautionary, considering the high uncertainty associated with the exploitation of an unfished stock. Despite the combination of high fishing costs and low prices, the fishery could still be profitable in the long term, although there is risk of overexploitation if high fishing effort is allowed..."

Merluza enana, stock no explotado, crecimiento individual, análisis bioeconómico, pesquería potencial Dwarf hake, unexploited stock, individual growth, bioeconomic analysis, potential fishery CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PECES Y FAUNA SILVESTRE REGLAMENTACIÓN Y CONTROL REGLAMENTACIÓN Y CONTROL