EFFECTS OF COVER CROP MANAGEMENT AND COMPOST APPLICATION ON SOIL FERTILITY OF ORGANIC MELON

A field experiment was carried out in Central Italy on growing melon (Cucumis melo L.) after barley (Hordeum vulgare L.). Three different systems of cover crop termination (green manure, roller crimper and fallow, as control) were combined with three doses of compost (0, 15 and 30 t ha-1 d.m.) in a strip plot design. The main objective of the research was to evaluate their effects on organic melon production and on short and long term soil nitrogen (N) fertility. Marketable yield and quality and soil N availability along the melon cycle were determined and a simplified N budget calculated. Green manure (GM) treatment showed the highest total and marketable yield, followed by fallow (FA), while roller crimper (RC) was characterized by a significant lower yield respect to the other two treatments (45% and 62% of the marketable yield of GM and FA, respectively). On the other side, long term soil N fertility of GM and FA were characterized by N deficit unless combined with compost application at the dose of 15 t ha-1 d.m

Differential mortality association of loop diuretic dosage according to blood urea nitrogen and carbohydrate antigen 125 following a hospitalization for acute heart failure

AimsRecent observations in chronic stable heart failure suggest that high-dose loop diuretics (HDLDs) have detrimental prognostic effects in patients with high blood urea nitrogen (BUN), but recent findings have also indicated that diuretics may improve renal function. Carbohydrate antigen 125 (CA125) has been shown to be a surrogate of systemic congestion. We sought to explore whether BUN and CA125 modulate the mortality risk associated with HDLDs following a hospitalization for acute heart failure (AHF).Methods and resultsWe analysed 1389 consecutive patients discharged for AHF. CA125 and BUN were measured at a mean of 72 ± 12 h after admission. HDLDs (≥120 mg/day in furosemide equivalent dose) were interacted to a four-level variable according to CA125 (>35 U/mL) and BUN (above the median), and related to all-cause mortality. At a median follow-up of 21 months, 561 (40.4%) patients died. The use of HDLDs was independently associated with increased mortality [hazard ratio (HR) 1.23, 95% confidence interval (CI) 1.01–1.50], but this association was not homogeneous across CA125–BUN categories (P for interaction <0.001). In patients with normal CA125, use of HDLDs was associated with high mortality if BUN was above the median (HR 2.29, 95% 1.51–3.46), but not in those with BUN below the median (HR 1.22, 95% CI 0.73–2.04). Conversely, in patients with high CA125, HDLDs showed an association with increased survival if BUN was above the median (HR 0.73, 95% CI 0.55–0.98) but was associated with increased mortality in those with BUN below the median (HR 1.94, 95% CI 1.36–2.76).ConclusionThe risk associated with HDLDs in patients after hospitalization for AHF was dependent on the levels of BUN and CA125. The information provided by these two biomarkers may be helpful in tailoring the dose of loop diuretics at discharge for AHF

Analysis of nanoprecipitation effect on toughness behavior in warm worked AA7050 alloy

Commonly adopted main methods aimed to improve the strength–toughness combination of high strength aluminum alloys are based on a standard process. Such a process includes alloy solution heat treatment, water-quench and reheating at controlled temperature for ageing holding times. Some alloys request an intermediate cold working hardening step before ageing for an optimum strength result. Recently a warm working step has been proposed and applied. This replaces the cold working after solution treatment and quenching and before the final ageing treatment. Such an alternative process proved to be very effective in improving strength–toughness behavior of 7XXX aluminum alloys. In this paper the precipitation state following this promising process is analyzed and compared to that of the standard route. The results put in evidence the differences in nanoprecipitation densities that are claimed to be responsible for strength and toughness improved properties

SVILUPPO DI UN PROCESSO A BASSO COSTO PER REALIZZARE MATERIALI COMPOSITI A MATRICE DI TITANIO MEDIANTE “ROLL DIFFUSION BONDING”.

rappresentano ad oggi la famiglia di materiali a più elevata resistenza specifica nel campo di temperature fino a 800°C. La maggiore riserva per una introduzione incisiva nelle applicazioni industriali è ancora il costo di questi materiali. Costo che è rappresentato dalla somma dei costi dei materiali costituenti e del processo di fabbricazione. Per quanto una diminuzione dei costi dei materiali costituenti sia sicuramente possibile per effetto dell’aumento dei volumi prodotti, le maggiori riserve sono concentrate sul processo di fabbricazione. Il processo standard consiste nella preparazione di lotti di precursori che vengono comunemente consolidati per compattazione isostatica a caldo, [2-7]. In questo filone il CSM ha investito risorse per ottenere una soluzione innovativa che ha permesso il contenimento della voce “costo di fabbricazione” rispetto alla linea di Compattazione Isostatica a Caldo (HIP) con un risparmio finale che ha raggiunto il 40%

Mulch-based no-tillage effects on weed community and management in an organic vegetable system

Weeds can cooperate with the agroecosystem\u2019s functioning by providing ecosystem services. Effective weed management should mitigate negative weed\u2013crop interference, while maintaining a functional and balanced weed community. In a two-year trial, the in-line/roller crimper (RC) was used to terminate an agroecological service crop (ASC; here barley, Hordeum vulgare L.) before organic zucchini (Cucurbita pepo, L.) and compared with green manure (GM) ASC and tilled no-ASC with Mater-Bi mulch on the rows (No_ASC). Zucchini yield, soil N availability, weed density/cover, biomass, and community composition were assessed. Analysis of variance, exploratory statistical analysis, and non-parametric inferential approaches were run, respectively, on agronomic data, species-specific weed frequencies, and Shannon diversity. Zucchini yield was the highest in No_ASC, due to soil N immobilization under high C:N barley residues in GM and RC. Multivariate analysis discriminated RC from tilled systems, outlining a specific ensemble of weed species correlated to Shannon diversity. From zucchini fruit set, RC selectively favored Polygonum aviculare L. and Helminthotheca echioides (L.), reasonably because of their oligotrophy and creeping habit. Their dominance finally caused low RC weed control. Results highlight strong weed selective pressure by the mulch-based no-tillage. Understanding the mechanisms underpinning the impact of soil management practices on weed community can drive towards a tailor-made and more effective weed management

Chronic elevation of pulmonary microvascular pressure in chronic heart failure reduces bi-directional pulmonary fluid flux

Aims. Chronic heart failure leads to pulmonary vascular remodelling and thickening of the alveolar–capillary barrier. We examined whether this protective effect may slow resolution of pulmonary oedema consistent with decreased bi-directional fluid flux. Methods and results. Seven weeks following left coronary artery ligation, we measured both fluid flux during an acute rise in left atrial pressure (n = 29) and intrinsic alveolar fluid clearance (n = 45) in the isolated rat lung. Chronic elevation of pulmonary microvascular pressure prevented pulmonary oedema and decreased lung compliance when left atrial pressure was raised to 20 cmH2O, and was associated with reduced expression of endothelial aquaporin 1 (P = 0.03). However, no other changes were found in mediators of fluid flux or cellular fluid channels. In isolated rat lungs, chronic LV dysfunction (LV end-diastolic pressure and infarct circumference) was also inversely related to alveolar fluid clearance (P ≤ 0.001). The rate of pulmonary oedema reabsorption was estimated by plasma volume expansion in eight patients with a previous clinical history of chronic heart failure and eight without, who presented with acute pulmonary oedema. Plasma volume expansion was reduced at 24 h in those with chronic heart failure (P = 0.03). Conclusions. Chronic elevation of pulmonary microvascular pressure in CHF leads to decreased intrinsic bi-directional fluid flux at the alveolar–capillary barrier. This adaptive response defends against alveolar flooding, but may delay resolution of alveolar oedema.A National Health and Medical Research Council (NHMRC) grant (#375129); Australian and New Zealand College of Anaesthetists (ANZCA) grant (#08/020); the Flinders Medical Centre Foundation

Green manure and compost effects on n-p dynamics in mediterranean organic stockless systems

Stockless systems, where plant and animal production are uncoupled, represent a common condition in Mediterranean areas. In organic systems, soil fertility is mainly managed by green manures, whereas composts of plant origin represent suitable soil conditioners. The low P content of these materials, together with the shortage of animal waste availability, determine potential nutrient depletion overtime and, in calcareous soils, P mining conditions. In a two-year field experiment in Central Italy, the effect of green manure vetch (Vicia villosa) (GM+) was compared with a control left fallow (GM-), combined with P-based fertilizers (F) on organic maize (Zea mays). Yields and N-P dynamics were evaluated by direct measurements, nutrient balance and efficiency index. N balance was higher than in GM+ GM- (+71.8 and -23.6 kg N ha-1, respectively). P enriched compost with RP (rock-phosphate) (EP), showed significant improvement in P use efficiency (meanly +34%) than other treatments (unfertilized control (RP), not P enriched compost (NEP)) and P equilibrium in the short run. On the other hand, P-fertilizers and maize residues soil incorporation determined P surplus in a long perspective (up to +10 kg P ha-1). Results emphasize the possibility of P reintegration in stockless organic systems without animal wastes

Comportamento meccanico in prove di fatica a caldo di compositi metallici a matrice di lega SP-700 rinforzata con fibre di Carburo di silicio tipo SCS-6

Il presente lavoro descrive le fasi di fabbricazione e di caratterizzazione di campioni di lega composita a matrice di titanio SP-700 e rinforzo costituito da fibre continue di SiC. I campioni fabbricati sono stati caratterizzati in microscopia , prima e dopo la compattazione isostatica a caldo. Il materiale è stato sottoposto a prove di trazione e fatica a temperatura ambiente, 450°C e 600°C. Sono illustrati i risultati delle prove che hanno mostrato una resistenza in trazione di almeno il 20% superiore a quelle della sola matrice. Infine sono state esaminate le superficie le sezioni di frattura delle provette sottoposte a fatica per descrivere le modalità ed i fenomeni agenti durante la deformazione