509 research outputs found
Control de malas hierbas: Densidades de siembra y rotaciones de cultivo
11 páginas, tablas estadísticas, y figuras.La rotación de cultivos ha sido uno de los métodos tradicionales para el control
de las malas hierbas, que se ha visto desplazada por factores económicos,
monocultivo de cereal y uso de herbicidas. Por otra parte no siempre son evidentes las
ventajas de una aplicación de herbicidas, particularmente en densidades bajas de
infestación de malas hierbas (Pardo et al., 2002 y Chao et al., 2002).
Aumentar las densidades de siembra en los cereales también han sido
empleadas como forma de aumentar la competencia del cultivo frente a las hierbas
acompañantes y disminuir de esa forma el daño que estas causan en los rendimientos
de los cereales. Actualmente sigue empleándose la expresión de “sembrar con mucho
pan” para justificar está practica tradicional. Determinar la densidad optima de siembra
ha sido objeto de varios trabajos con desigual resultado (Moreno et al., 2002 y Lacasta
et al., 2004), las causas son las diferentes condiciones experimentales.
En este trabajo se pretende evaluar la interacción de estas dos formas
tradicionales de control de malas hierbas (rotación de cultivos y densidades de
siembra) y su efecto sobre la productividad del cereal en las condiciones de
semiáridez de los secanos y en un experimento de larga duración (14 años).Peer reviewe
Post-traumatic overload or acute syndrome of the os trigonum: a possible cause of posterior ankle impingement
The purpose of this paper is to discuss the post-traumatic overload syndrome of the os trigonum as a possible cause of posterior ankle impingement and hindfoot pain. We have reviewed 19 athletes who were referred to our foot unit between 1995 and 2001 because of posterior ankle pain, and in whom a post-traumatic overload syndrome of os trigonum was diagnosed. All these patients were followed up over a period of 2 years. In 11 cases a chronic repetitive movements in forced plantar flexion was found. In the other eight cases the pain appeared to persist after a standard treatment of an ankle sprain in inversion plantar flexion. The diagnosis was based on clinical history, physical examination and X-rays that revealed a non-fused os trigonum. The confirmation of diagnosis was carried-out injecting local anaesthetic under fluoroscopic control. In all cases a corticosteroid injection as first line treatment was performed. In 6 cases a second injection was necessary to alleviate pain because incomplete recovery with the first injection. Three cases (16%) were recalcitrant to this treatment and in these three cases a surgical excision of the os trigonum was carried out. Our conclusion is that after some chronic athletic activity or an acute ankle sprain the os trigonum, if present, may undergo mechanical overload, remain undisrupted and become painful. Treatment by corticosteroid injection often resolves the proble
Ancient mitochondrial genomes unveil the origins and evolutionary history of New Zealand's enigmatic takahē and moho.
Many avian species endemic to Aotearoa New Zealand were driven to extinction or reduced to relict populations following successive waves of human arrival, due to hunting, habitat destruction and the introduction of mammalian predators. Among the affected species were the large flightless South Island takahē (Porphyrio hochstetteri) and the moho (North Island takahē; P. mantelli), with the latter rendered extinct and the former reduced to a single relictual population. Little is known about the evolutionary history of these species prior to their decline and/or extinction. Here we sequenced mitochondrial genomes from takahē and moho subfossils (12 takahē and 4 moho) and retrieved comparable sequence data from takahē museum skins (n = 5) and contemporary individuals (n = 17) to examine the phylogeny and recent evolutionary history of these species. Our analyses suggest that prehistoric takahē populations lacked deep phylogeographic structure, in contrast to moho, which exhibited significant spatial genetic structure, albeit based on limited sample sizes (n = 4). Temporal genetic comparisons show that takahē have lost much of their mitochondrial genetic diversity, likely due to a sudden demographic decline soon after human arrival (~750 years ago). Time-calibrated phylogenetic analyses strongly support a sister species relationship between takahē and moho, suggesting these flightless taxa diverged around 1.5 million years ago, following a single colonisation of New Zealand by a flighted Porphyrio ancestor approximately 4 million years ago. This study highlights the utility of palaeogenetic approaches for informing the conservation and systematic understanding of endangered species whose ranges have been severely restricted by anthropogenic impacts
MRI in multiple myeloma : a pictorial review of diagnostic and post-treatment findings
Magnetic resonance imaging (MRI) is increasingly being used in the diagnostic work-up of patients with multiple myeloma. Since 2014, MRI findings are included in the new diagnostic criteria proposed by the International Myeloma Working Group. Patients with smouldering myeloma presenting with more than one unequivocal focal lesion in the bone marrow on MRI are considered having symptomatic myeloma requiring treatment, regardless of the presence of lytic bone lesions. However, bone marrow evaluation with MRI offers more than only morphological information regarding the detection of focal lesions in patients with MM. The overall performance of MRI is enhanced by applying dynamic contrast-enhanced MRI and diffusion weighted imaging sequences, providing additional functional information on bone marrow vascularization and cellularity. This pictorial review provides an overview of the most important imaging findings in patients with monoclonal gammopathy of undetermined significance, smouldering myeloma and multiple myeloma, by performing a 'total' MRI investigation with implications for the diagnosis, staging and response assessment. Main message aEuro cent Conventional MRI diagnoses multiple myeloma by assessing the infiltration pattern. aEuro cent Dynamic contrast-enhanced MRI diagnoses multiple myeloma by assessing vascularization and perfusion. aEuro cent Diffusion weighted imaging evaluates bone marrow composition and cellularity in multiple myeloma. aEuro cent Combined morphological and functional MRI provides optimal bone marrow assessment for staging. aEuro cent Combined morphological and functional MRI is of considerable value in treatment follow-up
Development and Optimization of a GMP-Compliant Manufacturing Process for a Personalized Tumor Lysate Dendritic Cell Vaccine.
With the emergence of immune checkpoint inhibitors and adoptive T-cell therapies, there is a considerable interest in using personalized autologous dendritic cell (DC) vaccines in combination with T cell-targeting immunotherapies to potentially maximize the therapeutic impact of DC vaccines. Here, we describe the development and optimization of a Good Manufacturing Practice (GMP)-compliant manufacturing process based on tumor lysate as a tumor antigen source for the production of an oxidized tumor cell lysate loaded DC (OC-DC) vaccine. The manufacturing process required one day for lysate preparation and six days for OC-DC vaccine production. Tumor lysate production was standardized based on an optimal tumor digestion protocol and the immunogenicity was improved through oxidation using hypochloric acid prior to freeze-thaw cycles resulting in the oxidized tumor cell lysate (OC-L). Next, monocytes were selected using the CliniMACS prodigy closed system and were placed in culture in cell factories in the presence of IL-4 and GM-CSF. Immature DCs were loaded with OC-L and matured using MPLA-IFNγ. After assessing the functionality of the OC-DC cells (IL12p70 secretion and COSTIM assay), the OC-DC vaccine was cryopreserved in multiple doses for single use. Finally, the stability of the formulated doses was tested and validated. We believe this GMP-compliant DC vaccine manufacturing process will facilitate access of patients to personalized DC vaccines, and allow for multi-center clinical trials
Patients' satisfaction with community treatment: a pilot cross-sectional survey adopting multiple perspectives.
ACCESSIBLE SUMMARY: Patients' satisfaction is scarcely studied within the context of community treatment for adolescents. Thus, this study adopts a multiple perspective on patients' satisfaction (including service users as well as staff members). The results highlighted that all informants (patients, foster carers in foster homes and professional caregivers from community treatment teams) perceived the patients to be satisfied, with foster carers reporting the highest patient satisfaction rate. Considering the patient satisfaction rate from multiple perspectives provides complementary understandings. Clinical outcomes and, specifically, a reduction in emotional difficulties were related to patient's satisfaction, but only from the patients' perspective.
ABSTRACT: Community treatment (CT) teams in Switzerland provide care to patients who are unable to use regular child and adolescent mental health services (i.e. inpatient and outpatients facilities). No study has considered patients' self-rated satisfaction alongside with staff members' perspectives on patient satisfaction. Thus, adopting a cross-sectional survey design, we collected patients' satisfaction using the Client Satisfaction Questionnaire (CSQ-8), rated by multiple informants (patients, foster carers in foster homes and professional caregivers from CT teams). Professional caregivers assessed clinical outcomes using the Health of the Nation Outcome Scale for Children and Adolescents. The results indicated that all informants were satisfied with the community treatment teams. The satisfaction scores were not correlated across informants; however, the alleviation of emotional symptoms was correlated with patients' satisfaction. This study indicated that the use of a combined approach including the views of service users and professionals gives important complementary information. Finally, in our sample, lower emotional symptoms were linked to enhanced patient satisfaction. This study demonstrated the importance of considering multiple perspectives to obtain the most accurate picture of patients' satisfaction. Second, focusing on the reduction of emotional symptoms might lead to a higher degree of patients' satisfaction
Constant regulation for stable CD8 T-cell functional avidity and its possible implications for cancer immunotherapy.
The functional avidity (FA) of cytotoxic CD8 T cells impacts strongly on their functional capabilities and correlates with protection from infection and cancer. FA depends on TCR affinity, downstream signaling strength, and TCR affinity-independent parameters of the immune synapse, such as costimulatory and inhibitory receptors. The functional impact of coreceptors on FA remains to be fully elucidated. Despite its importance, FA is infrequently assessed and incompletely understood. There is currently no consensus as to whether FA can be enhanced by optimized vaccine dose or boosting schedule. Recent findings suggest that FA is remarkably stable in vivo, possibly due to continued signaling modulation of critical receptors in the immune synapse. In this review, we provide an overview of the current knowledge and hypothesize that in vivo, codominant T cells constantly "equalize" their FA for similar function. We present a new model of constant FA regulation, and discuss practical implications for T-cell-based cancer immunotherapy
Charge-ordering induces magnetic axes rotation in organic materials (TMTTF)₂X (with X = SbF₆, AsF₆, and PF₆)
We have performed a comprehensive EPR investigation of the quasi-one-dimensional organic systems
(TMTTF)₂X with centrosymmetrical anions X (X = SbF₆, AsF₆, and PF₆). We observe a strong rotation of g-factor
principal axes when the temperature decreases below charge-ordering temperature TCO. The possible origin of
this rotation is analyzed on the basis of quantum chemical calculations performed using density functional theory
method. A good agreement between theory and experiment is found
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