913 resultados para protected crops


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The effect of protected cropping on the performance of two strawberry cultivars ('Festival' and 'Rubygem') and two breeding lines (Breeding Lines 1 and 2) was studied in subtropical Queensland, Australia over two years. Production in this area is affected by rain, with direct damage to the fruit and the development of fruit diseases before harvest. The main objective of the study was to determine whether plants grown under high plastic tunnels had less rain damage, less disease incidence, and higher yields than plants grown outdoors. Our studies show that marketable yields were up to 40% higher in the plants under the tunnels compared with yields of the plants outdoors. This was mainly because fruit from the plants grown under the tunnels had lower incidences of rain damage and/or grey mould. There were no consistent differences in the relative numbers of small and/or misshaped fruit in the two growing environments. This research highlights the potential of protected cropping for strawberry producers in subtropical areas that receive significant rainfall during the growing season.

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Protective cropping could be an effective system for growing specialty melons in the dry tropics of North Queensland. The growing system could reduce outdoor risks for production loss, improve fruit quality, increase yield per m2, allow production offseason, and used for supplying niche markets in a segment of the larger melon market in Australia. First evaluations in Giru, Queensland, included seven cultivars of fruit types 'Galia', 'Hami', 'Charentais', small 'Canary', and 'Rockmelon', transplanted July 25, 2013 under a high polyethylene-covered tunnel. Plants were grown at a density of 2.8 plants m-2 in containers filled with volcanic rock and irrigated with a complete nutrient solution. Pruning and trellising was done to a single vertical stem, keeping lateral shoots on the main stem after the 7th leaf node. After bearing small fruit, lateral shoots were cut off after their second or third leaf node. To facilitate insect pollination, a screen window in the tunnel was left partially opened. On November 20 the cultivars had combined marketable yields that ranged from 2.8 to 8.2 fruits m-2 and 3.1 to 7.8 kg m-2. Total soluble solids levels in fruit ranged from 6 to 13 °Brix. Cultivars 'Tempo' ('Galia'), 'Tikal' ('Canary') and 'Sultan' ('Charentais') had fruit yields that were up to 2.6 times greater than yields commonly achieved with field-grown rockmelon crops. Sugar levels in fruits and marketable yields may be increased with changes in fertigation management. Promising results in this first evaluation justify examination of a greater number of genetic materials, in addition to the development of economic feasibility studies and further adaptive research to refine crop recommendations for growing melons in protective cropping systems.

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Background & Aims: Inadequate feeding assistance and mealtime interruptions during hospitalisation may contribute to malnutrition and poor nutritional intake in older people. This study aimed to implement and compare three interventions designed to specifically address mealtime barriers and improve energy intakes of medical inpatients aged ≥65 years. Methods: Pre-post study compared three mealtime assistance interventions: PM: Protected Mealtimes with multidisciplinary education; AIN: additional assistant-in-nursing (AIN) with dedicated meal role; PM+AIN: combined intervention. Dietary intake of 254 patients (pre: n=115, post: n=141; mean age 80±8) was visually estimated on a single day in the first week of hospitalisation and compared with estimated energy requirements. Assistance activities were observed and recorded. Results: Mealtime assistance levels significantly increased in all interventions (p<0.01). Post-intervention participants were more likely to achieve adequate energy intake (OR=3.4, p=0.01), with no difference noted between interventions (p=0.29). Patients with cognitive impairment or feeding dependency appeared to gain substantial benefit from mealtime assistance interventions. Conclusions: Protected Mealtimes and additional AIN assistance (implemented alone or in combination) may produce modest improvements in nutritional intake. Targeted feeding assistance for certain patient groups holds promise; however, alternative strategies are required to address the complex problem of malnutrition in this population.

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Activation of β2-adrenergic receptors inhibits osteoblastic bone formation and enhances osteoclastic bone resorption. Whether β-blockers inhibit ovariectomy-induced bone loss and decrease fracture risk remains controversial. To further explore the role of β-adrenergic signaling in skeletal acquisition and response to estrogen deficiency, we evaluated mice lacking the three known β-adrenergic receptors (β-less). Body weight, percent fat, and bone mineral density were significantly higher in male β-less than wild-type (WT) mice, more so with increasing age. Consistent with their greater fat mass, serum leptin was significantly higher in β-less than WT mice. Mid-femoral cross-sectional area and cortical thickness were significantly higher in adult β-less than WT mice, as were femoral biomechanical properties (+28 to +49%, P < 0.01). Young male β-less had higher vertebral (1.3-fold) and distal femoral (3.5-fold) trabecular bone volume than WT (P < 0.001 for both) and lower osteoclast surface. With aging, these differences lessened, with histological evidence of increased osteoclast surface and decreased bone formation rate at the distal femur in β-less vs. WT mice. Serum tartrate-resistance alkaline phosphatase-5B was elevated in β-less compared with WT mice from 8–16 wk of age (P < 0.01). Ovariectomy inhibited bone mass gain and decreased trabecular bone volume/total volume similarly in β-less and WT mice. Altogether, these data indicate that absence of β-adrenergic signaling results in obesity and increased cortical bone mass in males but does not prevent deleterious effects of estrogen deficiency on trabecular bone microarchitecture. Our findings also suggest direct positive effects of weight and/or leptin on bone turnover and cortical bone structure, independent of adrenergic signaling.

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A major obstacle to 3-dimensional tissue engineering is incorporation of a functional vascular supply to support the expanding new tissue. This is overcome in an in vivo intrinsic vascularization model where an arteriovenous loop (AVL) is placed in a noncollapsible space protected by a polycarbonate chamber. Vascular development and hypoxia were examined from 3 days to 112 days by vascular casting, morphometric, and morphological techniques to understand the model's vascular growth and remodeling parameters for tissue engineering purposes. At 3 days a fibrin exudate surrounded the AVL, providing a scaffold to migrating inflammatory, endothelial, and mesenchymal cells. Capillaries formed between 3 and 7 days. Hypoxia and cell proliferation were maximal at 7 days, followed by a peak in percent vascular volume at 10 days (23.20±3.14% compared with 3.59±2.68% at 3 days, P<0.001). Maximal apoptosis was observed at 112 days. The protected space and spontaneous microcirculatory development in this model suggest it would be applicable for in vivo tissue engineering. A temporal window in a period of intense angiogenesis at 7 to 10 days is optimal for exogenous cell seeding and survival in the chamber, potentially enabling specific tissue outcomes to be achieved.

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Passively protected railway crossings are a major rail safety issue in Australia. Such crossings cannot be upgraded as such crossings are too numerous and the cost involved is prohibitive. Advanced Driver Assistance Systems (ADAS) have been shown to improve road safety and are widely used. These systems could be a solution to improve safety of passively protected crossings at a lower cost. Such complementary ADAS could result in driver’s over-trust due to the absence of Humane Machine Interface reflecting the quality of the information or the state of the ADAS (failure status). This paper demonstrates that driver’s exposure to crossing exhibiting fail-safe and non-fail safe properties could result in improperly allocating trust between technologies. We conducted a driving simulator study where participants (N=58) were exposed to three types of level crossing warning system on passive and active crossings. The results show that a significant proportion of participants over-trust the ADAS. Such drivers exhibit the same driving performance with the ADAS as when exposed to infrastructure based active crossing protection. They do not take the necessary safety precautions as they have a faster speed approach, reduced number of gaze toward the rail tracks and fail to stop at the crossing.

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In The Climate Change Review, Ross Garnaut emphasised that ‘Climate change and climate change mitigation will bring about major structural change in the agriculture, forestry and other land use sectors’. He provides this overview of the effects of climate change on food demand and supply: ‘Domestic food production in many developing countries will be at immediate risk of reductions in agricultural productivity due to crop failure, livestock loss, severe weather events and new patterns of pests and diseases.’ He observes that ‘Changes to local climate and water availability will be key determinants of where agricultural production occurs and what is produced.’ Gert Würtenberger has commented that modern plant breeding is particularly concerned with addressing larger issues about nutrition, food security and climate change: ‘Modern plant breeding has an increasing importance with regard to the continuously growing demand for plants for nutritional and feeding purposes as well as with regard to renewal energy sources and the challenges caused by climate changes.’ Moreover, he notes that there is a wide array of scientific and technological means of breeding new plant varieties: ‘Apart from classical breeding, technologies have an important role in the development of plants that satisfy the various requirements that industrial and agricultural challenges expect to be fulfilled.’ He comments: ‘Plant variety rights, as well as patents which protect such results, are of increasingly high importance to the breeders and enterprises involved in plant development programmes.’ There has been larger interest in the intersections between sustainable agriculture, environmental protection and food security. The debate over agricultural intellectual property is a polarised one, particularly between plant breeders, agricultural biotechnology companies and a range of environmentalist groups. Susan Sell comments that there are complex intellectual property battles surrounding agriculture: 'Seeds are at the centre of a complex political dynamic between stakeholders. Access to seeds concerns the balance between private rights and public obligations, private ownership and the public domain, and commercial versus humanitarian objectives.' Part I of this chapter considers debates in respect of plant breeders’ rights, food security and climate change in relation to the UPOV Convention 1991. Part II explores efforts by agricultural biotechnology companies to patent climate-ready crops. Part III considers the report of the Special Rapporteur for Food, Olivier De Schutter. It looks at a variety of options to encourage access to plant varieties with climate adaptive or mitigating properties.

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From a computer simulation of the 270 MHz 1H NMR spectra of hydroxyproline (Hyp) and its protected derivatives, precise values of ring vicinal coupling constants were obtained. These couplings were related to ring torsional angles, using a Karplus type analysis. From the NMR analysis it was observed that the pyrrolidine ring possesses a unique and highly homogeneous conformation (Cγ-exo form). Temperature dependence studies on protected dipeptides suggest that the pyrrolidine ring conformation is independent of backbone conformation. An unusual X-Hyp, β-turn was observed for Boc-Aib-Hyp-NHMe.