Less safety for more efficiency: Water relations and hydraulics of the invasive tree Ailanthus altissima (Mill.) Swingle compared with native Fraxinus ornus L

Invasion of natural habitats by alien trees is a threat to forest conservation. Our understanding of fundamental ecophysiological mechanisms promoting plant invasions is still limited, and hydraulic and water relation traits have been only seldom included in studies comparing native and invasive trees. We compared several leaf and wood functional and mechanistic traits in co-occurring Ailanthus altissima (Mill.) Swingle (Aa) and Fraxinus ornus L. (Fo). Aa is one of the most invasive woody species in Europe and North America, currently outcompeting several native trees including Fo. We aimed at quantifying inter-specific differences in terms of: (i) performance in resource use and acquisition; (ii) hydraulic efficiency and safety; (iii) carbon costs associated to leaf and wood construction; and (iv) plasticity of functional and mechanistic traits in response to light availability. Traits related to leaf and wood construction and drought resistance significantly differed between the two species. Fo sustained higher structural costs than Aa, but was more resistant to drought. The lower resistance to drought stress of Aa was counterbalanced by higher water transport efficiency, but possibly required mechanisms of resilience to drought-induced hydraulic damage. Larger phenotypic plasticity of Aa in response to light availability could also promote the invasive potential of the species

Seletividade de inseticidas aos predadores que ocorrem em soja.

bitstream/item/133674/1/ID12894-1987-1988sojaresultados-p83-87.pdfTrabalho apresentado na XVI Reunião de Pesquisa de Soja da Região Sul, Santa Maria, 1988

Uso de tecnologias em lavouras de trigo de Santa Catarina - safra 2009.

bitstream/item/128917/1/ID41960-2010-LVdocumentos96-p117-134.pd

EVA: Laparoscopic instrument tracking based on endoscopic video analysis for psychomotor skills assessment

INTRODUCTION: The EVA (Endoscopic Video Analysis) tracking system a new tracking system for extracting motions of laparoscopic instruments based on non-obtrusive video tracking was developed. The feasibility of using EVA in laparoscopic settings has been tested in a box trainer setup. METHODS: EVA makes use of an algorithm that employs information of the laparoscopic instrument's shaft edges in the image, the instrument's insertion point, and the camera's optical centre to track the 3D position of the instrument tip. A validation study of EVA comprised a comparison of the measurements achieved with EVA and the TrEndo tracking system. To this end, 42 participants (16 novices, 22 residents, and 4 experts) were asked to perform a peg transfer task in a box trainer. Ten motion-based metrics were used to assess their performance. RESULTS: Construct validation of the EVA has been obtained for seven motion-based metrics. Concurrent validation revealed that there is a strong correlation between the results obtained by EVA and the TrEndo for metrics such as path length (p=0,97), average speed (p=0,94) or economy of volume (p=0,85), proving the viability of EVA. CONCLUSIONS: EVA has been successfully used in the training setup showing potential of endoscopic video analysis to assess laparoscopic psychomotor skills. The results encourage further implementation of video tracking in training setups and in image guided surgery

Modello di trasporto di calore per il dimensionamento di un impianto geotermico a circuito aperto

Nonostante gli impianti geotermici a bassa entalpia siano considerati tra i sistemi di condizionamento pi\uf9 efficienti e rispettosi dell\u2019ambiente per i climi temperati, la loro diffusione in Italia \ue8 ancora piuttosto limitata a causa della carenza di informazioni sui vantaggi derivanti dalla loro installazione e talvolta da leggi e regolamenti ambientali troppo severi nei confronti dell\u2019utilizzo delle acque sotterranee. In particolare i sistemi a circuito aperto, in cui le acque sotterranee sono prelevate e restituite all\u2019acquifero attraverso due o pi\uf9 pozzi ubicati lungo la direzione di flusso della falda, necessitano di uno studio idrogeologico preliminare e di una modellazione numerica per la valutazione degli effetti ambientali. Nel seguito \ue8 riportato un esempio di modellazione numerica di trasporto di calore con il codice SEAWAT 4.0 per il dimensionamento di un impianto geotermico a circuito aperto nella porzione settentrionale della Provincia di Treviso

Functional differentiation of invasive and native plants along a leaf efficiency/safety trade-off

Plant invasive alien species (IAS) are a serious threat to biodiversity. Several studies have compared the functional features of IAS and native species to identify the functional traits, or set of traits, favouring the process of invasion. However, most of these studies analysed traits only related to carbon and nutrients, and the inclusion of traits related to water use and acquisition might be useful to describe the functions underlying plant invasion. Here we present an analysis of cost-related, hydraulic and leaf vein traits measured on a large assemblage of woody and herbaceous native and invasive species (93 species in total, 78 natives and 15 IAS), that co-occur in site types in the Mediterranean area with different water availability (i.e. xeric, mesic and hydric sites). IAS shared lower leaf construction costs and drought resistance, but potential higher efficiency in water transport (i.e. higher values of vein length per unit area/mass) than native species. Moreover, IAS and native species separated along the trade-offs drawn by the measured traits, suggesting that hydraulic and vein traits could set an important axis of variation between IAS and native species. At last, IAS tended to occupy the fast-growth region of the functional space, independently of growth form and site type. Hydraulic and vein traits provide stronger mechanistic linkages between construction costs and photosynthetic and growth rates, thus possibly playing a central role in determining the invasive potential of IAS. IAS could reduce costs associated with leaf construction and resistance to drought stress having, at the same time, high efficiency of water transport and photosynthetic rates by developing a denser venation network, translating to higher growth rates than native and more conservative species

Promotion and maintenance of physically active lifestyle in older outpatients 2 years after acute coronary syndrome

Aims: To examine long-term changes in lifestyle and exercise capacity of older patients hospitalized for acute coronary syndrome (ACS) involved in an innovative centre- and home-based exercise-based secondary prevention program. Methods: A sample of 118 patients with ACS (age 76 [72-80] years) was analysed. Long-term changes in self-reported weekly leisure-time physical activity (wLTPA), walking speed (WS), and estimated cardiorespiratory fitness (eCRF, VO2peak, mL/kg/min) were the outcome variables. The program consisted of seven individual on-site sessions including motivational interviewing to reach exercise goals. Exercise prescription was based on the results of a standardized moderate and perceptually regulated treadmill walk to estimate VO2peak. wLTPA, WS, and eCRF were assessed at 1 (baseline), 2, 3, 4, 6, 12, and 24 months after discharge. Results: 87, 76, and 70 patients completed follow-up at 6, 12, and 24 months, respectively. wLTPA significantly increased during the follow-up period (median METs/H/week 2.5, 11.2, 12.0, and 13.4 at baseline, 6, 12, and 24 months, respectively; P < 0.0001). At baseline, 18% of the sample met the current international guidelines for physical activity, while 75%, 70%, and 76% of them met the recommended values at 6-, 12-, and 24-month follow-up sessions, respectively. These results were associated with increasing median WS (2.9 ± 1.0, 4.3 ± 1.2, 4.5 ± 1.1, 4.5 ± 1.2 km/h, respectively, P < 0.0001), and VO2peak (16.5, 21.4, 21.1, 21.3 mL/kg/min, respectively, P < 0.0001). Conclusions: This early, individualized exercise intervention improved long-term adherence to a physically active lifestyle, walking capacity, and eCRF in older patients after ACS. Larger studies are needed to confirm short- and long-term clinical benefits of this intervention