Analysis and design of a leek-celery intercropping system using mechanistic and descriptive models

Intercropping leek (Allium porrum L.) and celery (Apium graveolens L.) was recognized as an option to reduce growth and reproductive potential of weeds while maintaining yield and product quality of both crops on a high level. To optimise the intercropping system for yield, quality and weed suppression a combined use of mechanistic and descriptive models, together with experimental work, was applied. An eco-physiological model was used to improve understanding of interplant competition based on physiological, morphological and phenological processes. The model was parameterised based on characteristics of the plants in monocultures and its performance was evaluated for the crop mixtures using experimental data from different growing seasons. After validation the model was used to simulate biomass production and quality of leek, celery and seed production of Common Groundsel (Senecio vulgaris L.) for a wide range of crop densities and times of weed emergence. In a second step, the results of the simulations where summarized using a descriptive hyperbolic yield-density model, which then allowed evaluation of the intercropping system in terms of productivity, product quality, and the ability to suppress weeds. The paper will explain this combined modelling approach and how it was used to design and optimise the leek-celery intercropping system. Moreover, this study shows that functional biodiversity, as represented by the intercropping system, can contribute to the improvement of the economical potential while increasing the sustainability of highly developed agricultural production systems

Territorialities in struggle surrounding a wind farm in Argentina

Este artículo analiza las tensiones en torno a la dimensión territorial de la implementación de un emprendimiento de energía eólica en un paraje rural de la provincia de Río Negro (Argentina). El proyecto, impulsado por una empresa de capitales chinos, logró su aprobación a partir de un Estudio de Impacto Ambiental que omitió mencionar que había una comunidad mapuche donde se planificaba ubicar el parque eólico. Durante el proceso de consulta desarrollado por solicitud de la comunidad, se pusieron en evidencia lógicas territoriales diferentes que se encuentran en relación asimétrica. El artículo da cuenta de ellas a partir de datos producidos en una investigación basada en el trabajo de campo etnográfico y en archivos. El foco está puesto en el análisis de la territorialidad expresada en el Estudio de Impacto Ambiental en contraste con la que propone la comunidad con énfasis en la dimensión ontológica del problema de la tierra.This essay addresses territorial tensions that emerged within negotiations related to a wind farm project aimed to be located in a rural setting in Río Negro province (Argentina). The project is promoted by a Chinese company and was accepted due to an Environmental Impact Assessment that missed to mention that there was a Mapuche community where the wind farm was intended to be located. Therefore, the community requested the development of a consultation process. In this process, different territorial logics were put into play, however within asymmetrical relations. The essay approaches these logics based on empirical evidence that was gathered through ethnographic fieldwork and archive research. The argument focuses on the territorial assumptions expressed in the Environmental Impact Assessment in comparison with those sustained by the community emphasizing on the different ways of understanding what land is.Fil: Kropff Causa, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Diversidad Cultural y Procesos de Cambio. Universidad Nacional de Río Negro. Instituto de Investigaciones en Diversidad Cultural y Procesos de Cambio; ArgentinaFil: Spivak L´hoste, Ana Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Sociales. Instituto de Desarrollo Económico y Social. Centro de Investigaciones Sociales; Argentin

Relative humidity predicts day-to-day variations in COVID-19 cases in the city of Buenos Aires

Possible links between the transmission of COVID-19 and meteorology have been investigated by comparing positive cases across geographical regions or seasons. Little is known, however, about the degree to which environmental conditions modulate the daily dynamics of COVID-19 spread at a given location. One reason for this is that individual waves of the disease typically rise and decay too sharply, making it hard to isolate the contribution of meteorological cycles. To overcome this shortage, we here present a case study of the first wave of the outbreak in the city of Buenos Aires, which had a slow evolution of the caseload extending along most of 2020. We found that humidity plays a prominent role in modulating the variation of COVID-19 positive cases through a negative-slope linear relationship, with an optimal lag of 9 days between the meteorological observation and the positive case report. This relationship is specific to winter months, when relative humidity predicts up to half of the variance in positive case count. Our results provide a tool to anticipate possible local surges in COVID-19 cases after events of low humidity. More generally, they add to accumulating evidence pointing to dry air as a facilitator of COVID-19 transmission.Fil: Pineda Rojas, Andrea Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; ArgentinaFil: Cordo, Sandra Myriam. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Saurral, Ramiro Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmósfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmósfera; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Jimenez, Jose L.. State University of Colorado at Boulder; Estados UnidosFil: Marr, Linsey C.. Virginia Tech University; Estados UnidosFil: Kropff, Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentin

Competition between a sugar beet crop and populations of Chenopodium album L. and Stellaria media L.

Analyse van de inlvoed van de morfologie van de onkruiden melganzevoet en vogelmuur op het concurrentievermoge

DSMM XI study: dose definition for intravenous cyclophosphamide in combination with bortezomib/dexamethasone for remission induction in patients with newly diagnosed myeloma

A clinical trial was initiated to evaluate the recommended dose of cyclophosphamide in combination with bortezomib and dexamethasone as induction treatment before stem cell transplantation for younger patients with newly diagnosed multiple myeloma (MM). Thirty patients were treated with three 21-day cycles of bortezomib 1.3 mg/m2 on days 1, 4, 8, and 11 plus dexamethasone 40 mg on the day of bortezomib injection and the day after plus cyclophosphamide at 900, 1,200, or 1,500 mg/m2 on day 1. The maximum tolerated dose of cyclophosphamide was defined as 900 mg/m2. At this dose level, 92% of patients achieved at least a partial response. The overall response rate [complete response (CR) plus partial response (PR)] across all dose levels was 77%, with a 10% CR rate. No patient experienced progressive disease. The most frequent adverse events were hematological and gastrointestinal toxicities as well as neuropathy. The results suggest that bortezomib in combination with cyclophosphamide at 900 mg/m2 and dexamethasone is an effective induction treatment for patients with newly diagnosed MM that warrants further investigation