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Synergistic effect of above- and belowground short-term recovery in alpine meadows driven by grass debris mulching
No full textAlpine grassland ecosystems are facing severe degradation due to climate change and anthropogenic activities, necessitating effective recovery strategies. Conventional approaches often improved productivity, but fail to achieve soil functions and ecosystem multifunctionality. This study examined the efficacy of grass debris mulching (cultivated grassland recovery with mulching, CGRM) compared to traditional cultivated grassland recovery (cultivated grassland recovery, CGR) in rehabilitating the severely degraded alpine meadows located in the Tibetan Plateau, China. A three-year field experiment was conducted with 21 closed plots, including the extremely degraded alpine meadow as control (EDAM), the normal alpine meadow (NAM), and the two recovery treatments CGRM and CGR. Grassland ecosystem short-term recovery effectiveness was assessed through microhabitat, above- and belowground ecosystem components. Results demonstrated that CGRM significantly enhanced microhabitat by increasing soil moisture (+16.17 %) and stabilizing temperature (+34.04 %) at 0–10 cm soil layer. It enhanced aboveground recovery with greater plant coverage (+34.82 %), density (+71.12 %), aboveground biomass (+54.87 %), and belowground biomass (+31.94 %) of 0–30 cm soil layer surpassing CGR. Despite a short-term decrease in soil organic carbon (–16.2 %),CGRM improved soil pore structure (+8.45 %), water-holding capacity (+20.66 %), water transport capacity (+258.47 %) and erosion resistance capacity (+109.15 %). Overall, CGRM achieved 26.30 % higher overall ecosystem recovery than CGR by balancing trade-offs among microhabitat, above- and belowground ecosystem components. Our study challenges the conventional paradigm that prioritizes rapid greening over functional recovery. These results demonstrate that grass debris mulching enhances both structural and functional recovery, providing a scalable approach for restoring degraded alpine ecosystems under climate warming
Oferta y ocupación de plazas. Curso 2025-2026. Universidad de Zaragoza
No full textEl campo plazas ofertadas recoge la oferta de plazas de estudiantes de nuevo ingreso para cada curso.
Plazas matriculadas indica el número de plazas ocupadas por matriculados de nuevo ingreso.
No se consideran matriculados de nuevo ingreso los que acceden a un estudio por cambio de estudios, traslado de expediente o adaptación al grado.
Plazas solicitadas es el número de peticiones de acceso a un plan de estudios. Cada solicitante se cuenta tantas veces como cupos de adjudicación haga constar en su solicitud de admisión.
Índice de ocupación es la relación porcentual que se obtiene de dividir las medidas "plazas matriculadas" y "plazas ofertadas".
Plazas ofertadas, matriculadas y solicitadas e índice de ocupación de plazas por titulación y localidad
Borell's inequality and mean width of random polytopes via discrete inequalities
No full textBorell's inequality states the existence of a positive absolute constant C>0 such that for every 1≤p≤q(E|〈X,en〉|p)1p≤(E|〈X,en〉|q)1q≤Cqp(E|〈X,en〉|p)1p, whenever X is a random vector uniformly distributed on any convex body K⊆Rn and (ei)i=1n is the standard canonical basis in Rn. In this paper, we will prove a discrete version of this inequality, which will hold whenever X is a random vector uniformly distributed on K∩Zn for any convex body K⊆Rn containing the origin in its interior. We will also make use of such discrete version to obtain discrete inequalities from which we can recover the estimate Ew(KN)∼w(ZlogN(K)) for any convex body K containing the origin in its interior, where KN is the centrally symmetric random polytope KN=conv{±X1,…,±XN} generated by independent random vectors uniformly distributed on K, Zp(K) is the Lp-centroid body of K for any p≥1, and w(⋅) denotes the mean width
Multivariate integration of time series with ML for corn price forecasting in Colombia
Full text linkThe volatility of corn prices poses a significant challenge for both producers and policymakers. This study proposes a hybrid model that combines Extreme Gradient Boosting (XGBoost) and Light Gradient Boosting Machine (LightGBM), optimized through Particle Swarm Optimization with Cuckoo Search (PSO-CS), for accurate corn price forecasting. The approach integrates multivariate time series data, including local prices from the Atlántico market and international futures prices from the Chicago Board of Trade (CBOT). Empirical Mode Decomposition (EMD) is applied to enhance signal clarity and improve model performance. Model performance is assessed through sensitivity analysis and statistical comparison using the Diebold-Mariano (DM) test. The results demonstrate that the proposed ensemble outperforms both individual models and neural network combinations, achieving a Mean Absolute Percentage Error (MAPE) of 2.06
Alumnos matriculados. Sexo, dedicación y procedencia. Curso 2025-2026. Universidad de Zaragoza
No full textEl campo localidad identifica la comunidad autónoma de residencia familiar indicada por el alumno en el curso académico en que se matricula.
El campo programa de movilidad de salida indica si los estudiantes participan en un programa de intercambio nacional o internacional de salida (S) o no (N) en el curso académico seleccionado.
El campo dedicación tiene como valores posibles: tiempo completo, tiempo parcial, otra dedicación (finalizando estudios, con menos del 15% de los créditos del plan de estudios por superar). Existe un número mínimo de créditos en que deberán matricularse los estudiantes, en función de cada modalidad.
Número de alumnos matriculados por localidad, centro y titulación según la Comunidad Autónoma de procedencia, sexo, tipo de acceso y dedicación
Standardizing CASA analysis to accurately assess sea urchin Paracentrotus lividus sperm motility
No full textAlthough computer-assisted sperm analysis (CASA) system is widely applied for evaluating sperm motility in numerous vertebrate species, its application to sea urchin sperm remains comparatively underexplored, with limited data available on this invertebrate model. This study aimed to standardize the frame rate, type of counting chambers, extender, and dilution rate to use CASA system to evaluate sea urchin sperm motility. Semen samples were collected and diluted in artificial sea water alone (ASW) or supplemented with 0.3 % serum bovine albumin (ASW-BSA). The diluted semen was filled in 4 chamber types: drop displacement, Spermtrack® (SK) and R2D10 (R2); and capillary, Kubus® (KU); and SpermLide® (SL). Three dilutions ranging from low to high were studied. Sperm motility was evaluated using a commercial CASA system (AI Station v1.2; Sperm Analysis Technologies S.L., Buñol, Spain) that employs artificial intelligence for sperm recognition. Spermatozoa were immotile in drop displacement chambers when diluted in ASW; however total motility (TMOT) and progressivity (PMOT) did not differ significantly across chamber types when semen was diluted in ASW-BSA, independently of filling chamber type. KU chamber showed significantly higher velocity parameters compared to SL chamber when semen was diluted in ASW. However, these differences disappeared when in ASW-BSA medium, and straight line velocity (VSL) was even significantly higher in SL chamber. As dilution increased (i.e., lower cell concentration), sperm velocity increased, and linearity decreased. The optimal frame rate for accurate measurement of curvilinear velocity (VCL) was 510 fps, whereas lower frame rates (< 360 fps) were sufficient for evaluating VSL and average path velocity (VAP). In conclusion, to optimally assess sea urchin sperm motility using CASA requires a frame rate of 510 fps, dilution in ASW-BSA to concentrations below 75 × 106 sperm/mL and using capillary-filling chambers
A Computational Fluid Dynamics model for predicting food browning through melanoidin kinetics during baking
No full textFood browning during cooking often results from Maillard reaction, though other processes, such as caramelisation and enzymatic browning, also contribute depending on the type of food and cooking conditions. This paper presents a browning model based on Maillard reaction kinetics that integrates into comprehensive CFD baking models, predicting melanoidin concentration and food browning during baking. Initial validation uses data from established studies on the Maillard reaction and melanoidin formation in simplified model systems (sugar–amino acid mixtures heated under controlled conditions). Further experimental validation involves baking muffins in a domestic oven, comparing observed surface browning and melanoidin absorption with the model’s simulated browning index and melanoidins over time. A method for calculating the browning index from experiments and CFD simulations is presented. Validation shows differences in melanoidin concentration and browning index between measurements and simulations below 8% and 7%, respectively, across all baking times. This research provides insight into the mechanisms of browning reactions in baked goods, enabling the integration of Maillard reaction kinetics into CFD models. These findings offer practical tools for predicting browning, allowing the food industry to optimise baking processes, improve product consistency, and enhance safety and quality
Implementación de la vía RICA en cirugía urgente: adherencia, barreras y facilitadores
No full textAntecedentes y objetivo
La vía clínica de recuperación intensificada en cirugía del adulto (RICA) ha demostrado mejorar los resultados posoperatorios en cirugía electiva pero su implementación en entornos urgentes sigue siendo limitada y poco estudiada. El objetivo del estudio es evaluar el grado de adherencia a determinadas medidas RICA perioperatorias en cirugías urgentes frecuentes (apendicectomía, colecistectomía y úlcera péptica perforada no neoplásica), así como identificar barreras y facilitadores para su aplicación.
Materiales y métodos
Estudio observacional descriptivo, prospectivo y exploratorio que incluye 206 pacientes consecutivos sometidos a alguna de las cirugías urgentes seleccionadas entre noviembre de 2021 y julio de 2022. Se evaluó la adherencia a medidas RICA en las fases preoperatoria, intraoperatoria y posoperatoria inmediata. También se analizaron barreras y facilitadores mediante revisión bibliográfica, elaboración de una matriz estandarizada, entrevistas no estructuradas y observación directa.
Resultados
La adherencia global fue superior al 70% en la mayoría de los ítems, identificando mayor variabilidad, como era previsible, en aquellas medidas dependientes de la complejidad del caso, como el uso de drenajes o sondas. La principal barrera fue organizativa y la experiencia previa de RICA en cirugía electiva actuó como facilitador.
Conclusiones
La aplicación de determinadas medidas RICA perioperatorias en cirugía urgente es factible, presentando una alta adherencia en entornos con experiencia previa en cirugía electiva. La principal barrera detectada fue organizativa, mientras que la cultura institucional consolidada fue un facilitador clave. Son necesarios estudios con diseños metodológicamente robustos, que incluyan evaluación de resultados clínicos y puedan respaldar su implementación como estándar asistencial.
Background and objective
The Enhanced Recovery After Surgery (ERAS) clinical pathway has been shown to improve postoperative outcomes in elective surgery but its implementation in emergency settings remains limited and understudied. The aim of the study is to assess the degree of adherence to selected perioperative ERAS items in frequent emergency surgeries (appendectomy, cholecystectomy and non-neoplastic perforated peptic ulcer), as well as to identify barriers and facilitators for its implementation.
Materials and methods
Descriptive, prospective and exploratory observational study including 206 consecutive patients undergoing one of the selected emergency surgeries between November 2021 and July 2022. Adherence to ERAS items was assessed in the preoperative, intraoperative and immediate postoperative phases. Barriers and facilitators were also analysed through literature review, standardised matrix development, unstructured interviews and direct observation.
Results
Overall adherence was over 70% for most items, with greater variability, as expected, in those measures dependent on the complexity of the case, such as the use of drains or tubes. The main barrier was organisational and the previous experience of ERAS in elective surgery acted as a facilitator.
Conclusions
The implementation of certain perioperative ERAS items in emergency surgery is feasible, presenting high adherence in settings with previous experience in elective surgery. The main barrier detected was organisational, while the consolidated institutional culture was a key facilitator. Studies with methodologically robust designs, including evaluation of clinical outcomes, are needed to support its implementation as a standard of care
Collective Intrahousehold Labor Supply in Europe: Distribution Factors and Policy Implications
Full text linkThis paper analyzes how variables that shape intrahousehold bargaining relate to spouses’ labor supply. We estimate a collective model using data from the EU-SILC over 2004–2019 for 17 countries. Results provide evidence of the relevance of the following distribution factors: sex ratio, non-labor income, age difference, education difference, and fertility rates. The sex ratio seems to be a distribution factor in Czech Republic, Denmark, Hungary, Ireland, Italy, Poland, Spain, and Switzerland. In addition, the wife’s share of non-labor income is a distribution factor in Belgium, Czech Republic, Estonia, Ireland, Italy, Luxembourg, Poland, Portugal, Spain, and the UK. In Austria, Belgium, Czech Republic, Denmark, Estonia, France, Ireland, Italy, Luxembourg, Switzerland, and the UK the spouses’ age gap displays opposite signs on spouses’ labor supply, whereas in Austria, Belgium, Czech Republic, Denmark, France, Hungary, Ireland, Luxembourg, Portugal, and the UK the spouses’ education level differences display intrahousehold bargaining signs. Finally, the fertility rate is a distribution factor in Austria, Czech Republic, Denmark, Estonia, France, Ireland, Latvia, Portugal, Switzerland, and the UK. These results indicate that spousal- and country-specific characteristics are assessed differently across Europe and may help planners to implement household policies on cash transfers, schooling, and fertility