A comparative study of the characteristics and physical behaviour of different packing materials commonly used in biofiltration

[Abstract] In this study, the characteristics and physical behaviour of 8 different packing materials were compared. The materials were selected according to previous works in the field of biofiltration including organic and inorganic or synthetic materials. Results pre-selected those more acceptable support materials for the main function they have to perform in the biological system: high surface contact, rugosity to immobilize the biomass, low pressure drop, nutrients supply, water retentivity or a commitment among them. Otherwise, pressure drop have been described by means of the respective mathematic expressions in order to include phenomena in the classical biofiltration models.Ministerio de Educación y Ciencia; CTQ2006 – 14997-C02-0

Compaction caused by soil tillage and seedbed preparation: effects on weed emergence in a barley crop

El objetivo principal de este trabajo fue evaluar los efectos de la compactación producida por la frecuencia de pases y el tipo de apero utilizado en la siembra del cereal, sobre la emergencia de las malas hierbas. Se utilizó un diseño en parcelas subdivididas con 4 repeticiones, con la labor primaria (fresa vs. cultivador) en parcelas principales y el pase de rulo (liso vs. pratenses) en subparcelas. Se tomaron datos de malas hierbas (densidad, biomasa) y de propiedades físicas del suelo (compactación, densidad aparente). Los resultados no han mostrado diferencias debidas a la labor primaria en ninguna de las variables analizadas, pero sí en función del tipo y frecuencia de pases de rulo, observándose menor densidad y biomasa de malas hierbas cuanto mayor era el número de pases de rulo, especialmente el liso, coincidiendo con los suelos más compactados. Sin embargo, parece existir un límite en el cual dejan de producirse efectos significativos debido a una sobrecompactación (e.g. doble pase de rulo y zona de rodada).The main objective of this work was to evaluate the effects of the compaction produced by the frequency of passes and the type of implement used in seedbed preparation, on weed emergence. A split-plot design with 4 replications was used, with the primary tillage (cultivator vs. rotary tiller) in main plots and rolling (flat roller vs. Cambridge roller) in subplots. Weeds data (density, biomass) and soil physical properties (compaction, bulk density) were assessed. The results showed no differences due to the primary tillage in any of the analyzed variables. However, the type and frequency of roller passes resulted in significant differences in weed abundance, with lower weed density and biomass when the number of roller passes was greater (especially flat roller), which coincided with the higher compaction. However, it seems to be a limit at which significant effects no longer occur due to an overcompaction (e.g. double roller pass and tractor wheel traffic)

Effect of wheel track on the density and composition of weeds in a maize crop

El objetivo de este estudio fue analizar si la compactación producida por la rodada del tractor durante las operaciones de siembra influye en la composición y densidad de malas hierbas en cultivo de maíz. Para ello se llevó a cabo el conteo e identificación de las especies presentes en 160 unidades muestrales localizadas en la interlínea de cultivo, de las cuales la mitad estaba afectada por la rodada del tractor y la otra mitad no. El contraste de medias entre los datos con rodada y sin rodada para la riqueza de especies, densidad total y densidad por especies se realizó mediante el test de Mann-Whitney. Los resultados han puesto de manifiesto que las especies principales, a excepción de “Cyperus rotundus”, fueron significativamente más abundantes en las interlíneas con rodada. En relación a la comunidad arvense, ésta fue igualmente más diversa y abundante en las interlíneas con rodada.The aim of this study was to analyze whether the compaction caused by the tractor during sowing operations affects the composition and density of the weed flora in maize crops. For that, 160 sample units were taken in the crop interline, where half of them were affected by the tractor tread and the other half not. In each sampling unit we carried out the count and identification of weed species. The Mann-Whitney test was performed to contrast differences in species richness, total and individual species densities between tractor-tread and not tractor-tread data. The results revealed that the main species, except for “Cyperus rotundus” were significantly more abundant in the interline with tractor tread. In relation to the weed community, it was also more diverse and abundant in the interline with tractor tread

Accompanying weeds of a poplar energy crop under different management strategies

Se han evaluado los efectos de distintas estrategias de manejo sobre las poblaciones de malas hierbas y la productividad (i.e. biomasa) de un cultivo energético de chopo en la zona centro de España. Para ello, se han realizado dos estudios: 1) análisis durante el primer año de cultivo, el más sensible a la competencia con arvenses, repetido tres veces; y 2) valoración al cabo de los tres años de duración del turno de corte. Los resultados han puesto de manifiesto una evolución de la flora arvense con el tiempo, encontrando cambios significativos según la estrategia de manejo. Al finalizar el turno de tres años, las estrategias más productivas fueron la cubierta vegetal sembrada con “Lolium multiflorum” y la basada en herbicidas, coincidiendo con una menor competencia de malas hierbas respecto a la estrategia estándar basada en labores.We have evaluated the effects of different management strategies on weed populations and productivity (i.e. biomass) of a poplar energy crop in central Spain. To do this, two studies have been performed: 1) analysis performed during the first year of production, the most sensitive to competition with weeds, repeated three times; and 2) an assessment after the three-year harvest cycle. The results have revealed a weed flora evolution over time, finding significant changes as a function of management strategies. At the end of the three-year harvest cycle, the most productive strategies were cover crop sown with “Lolium multiflorum” and that based on herbicides, coinciding with less competition with weeds compared to the standard strategy based on tillage

A multi-method approach towards understanding the pathophysiology of aortic dissections – the complementary role of in-silico, in-vitro and in-vivo information

Management and follow-up of chronic aortic dissections continues to be a clinical challenge due to progressive aortic dilatation. To predict dilatation, guidelines suggest follow-up of the aortic diameter. However, dilatation is triggered by haemodynamic parameters (pressure and wall shear stresses (WSS)), and geometry of false (FL) and true lumen (TL). We aimed at a better understanding of TL and FL haemodynamics by performing in-silico (CFD) and in-vitro studies on an idealized dissected aorta and compared this to a typical patient. We observed an increase in diastolic pressure and wall stress in the FL and the presence of diastolic retrograde flow. The inflow jet increased WSS at the proximal FL while a large variability in WSS was induced distally, all being risk factors for wall weakening. In-silico, in-vitro and in-vivo findings were very similar and complementary, showing that their combination can help in a more integrated and extensive assessment of aortic dissections, improving understanding of the haemodynamic conditions and related clinical evolution

Ischemic postconditioning reduces reperfusion arrhythmias by adenosine receptors and protein kinase C activation but is independent of KATP channels or connexin 43

Funding: This study was supported by Secretaría de Investigación, Internacionales y Posgrado, Universidad Nacional de Cuyo (06/J505) and by the Spanish, Ministerio de Ciencia, Innovación y Universidades, Instituto de Salud Carlos III (CIBERCV), cofinanced by the European Regional Development Fund (ERDF-FEDER, a way to build Europe), and by Fundació La Marató de TV3 (n◦. 201536-10). Antonio Rodríguez-Sinovas has a consolidated Miguel Servet contract. Jose A. Sánchez was supported by the International Research Training Group 1566 on Protecting the Heart from Ischemia (PROMISE).Ischemic postconditioning (IPoC) reduces reperfusion arrhythmias but the antiarrhythmic mechanisms remain unknown. The aim of this study was to analyze IPoC electrophysiological effects and the role played by adenosine A, A and A receptors, protein kinase C, ATP-dependent potassium (K) channels, and connexin 43. IPoC reduced reperfusion arrhythmias (mainly sustained ventricular fibrillation) in isolated rat hearts, an effect associated with a transient delay in epicardial electrical activation, and with action potential shortening. Electrical impedance measurements and Lucifer-Yellow diffusion assays agreed with such activation delay. However, this delay persisted during IPoC in isolated mouse hearts in which connexin 43 was replaced by connexin 32 and in mice with conditional deletion of connexin 43. Adenosine A, A and A receptor blockade antagonized the antiarrhythmic effect of IPoC and the associated action potential shortening, whereas exogenous adenosine reduced reperfusion arrhythmias and shortened action potential duration. Protein kinase C inhibition by chelerythrine abolished the protective effect of IPoC but did not modify the effects on action potential duration. On the other hand, glibenclamide, a K inhibitor, antagonized the action potential shortening but did not interfere with the antiarrhythmic effect. The antiarrhythmic mechanisms of IPoC involve adenosine receptor activation and are associated with action potential shortening. However, this action potential shortening is not essential for protection, as it persisted during protein kinase C inhibition, a maneuver that abolished IPoC protection. Furthermore, glibenclamide induced the opposite effects. In addition, IPoC delays electrical activation and electrical impedance recovery during reperfusion, but these effects are independent of connexin 43

Utilization of Sago Flour in Gluten-free Food Products

A gluten-free (GF) diet is currently the only treatment for celiac disease. This disease is triggered by genetic factors, and ingestion of gluten found primarily in products containing wheat may result in lesions in the intestinal lining and lead to nutrient malabsorption. Sago is GF; hence, its potential as part of a GF flour blend was evaluated in selected food products, namely, cookies, pretzels, and tortilla. Flour blend tests showed that the preferred ratios were the following: for cookies, 50% sago: 50% cassava flour; for pretzels, 50% sago: 50% rice flour; and for tortilla, 40% sago: 60% nixtamalized corn flour. Consumers’ rating of overall acceptability of the products ranged from “like moderately” to “like very much.” Proximate composition differed from wheat-based counterparts; notably, protein content was lower since sago flour is mostly carbohydrates. However, an advantage of sago flour is its antioxidant content. Total phenolic content determination showed 2.81 mg gallic acid equivalent (GAE) per gram of cookies and 4.07 mg GAE/g of pretzels. Like other GF products, the texture of the dough and the final products was problematic. The dough was difficult to form, and products were denser and crumbled easily after one to two days of storage. Further studies need to be done on the use of dough conditioners or other additives that may improve the products’ texture

Vascular Dysfunction in a Transgenic Model of Alzheimer's Disease: Effects of CB1R and CB2R Cannabinoid Agonists

There is evidence of altered vascular function, including cerebrovascular, in Alzheimer's disease (AD) and transgenic models of the disease. Indeed vasoconstrictor responses are increased, while vasodilation is reduced in both conditions. β-Amyloid (Aβ) appears to be responsible, at least in part, of alterations in vascular function. Cannabinoids, neuroprotective and anti-inflammatory agents, induce vasodilation both in vivo and in vitro. We have demonstrated a beneficial effect of cannabinoids in models of AD by preventing glial activation. In this work we have studied the effects of these compounds on vessel density in amyloid precursor protein (APP) transgenic mice, line 2576, and on altered vascular responses in aortae isolated ring. First we showed increased collagen IV positive vessels in AD brain compared to control subjects, with a similar increase in TgAPP mice, which was normalized by prolonged oral treatment with the CB1/CB2 mixed agonist WIN 55,212-2 (WIN) and the CB2 selective agonist JWH-133 (JWH). In Tg APP mice the vasoconstriction induced by phenylephrine and the thromboxane agonist U46619 was significantly increased, and no change in the vasodilation to acetylcholine (ACh) was observed. Tg APP displayed decreased vasodilation to both cannabinoid agonists, which were able to prevent decreased ACh relaxation in the presence of Aβ. In summary, we have confirmed and extended the existence of altered vascular responses in Tg APP mice. Moreover, our results suggest that treatment with cannabinoids may ameliorate the vascular responses in AD-type pathology.This work was supported by the Council of Madrid (S- BIO/0170/2006 and P2010/BMD-2349 to MLC) and by Instituto de Salud Carlos III/FISS (PI12/00590 to TT). AM received a fellowship from the Spanish Ministry of Education and Science and JN-D from FISS. Dr. R. Martínez-Murillo is acknowledged for preliminary EM experiments.Peer reviewedPeer Reviewe

Ageing, sex and cardioprotection

Translation of cardioprotective interventions aimed at reducing myocardial injury during ischaemia-reperfusion from experimental studies to clinical practice is an important yet unmet need in cardiovascular medicine. One particular challenge facing translation is the existence of demographic and clinical factors that influence the pathophysiology of ischaemia-reperfusion injury of the heart and the effects of treatments aimed at preventing it. Among these factors, age and sex are prominent and have a recognised role in the susceptibility and outcome of ischaemic heart disease. Remarkably, some of the most powerful cardioprotective strategies proven to be effective in young animals become ineffective during ageing. This article reviews the mechanisms and implications of the modulatory effects of ageing and sex on myocardial ischaemia-reperfusion injury and their potential effects on cardioprotective interventions