162 research outputs found
The effect of early leaf removal on whole-canopy gas exchange and vine performance of Vitis vinifera L. ‘Sangiovese’
The physiological effects induced at the whole canopy level by early vine defoliation, which has already proven to be very effective in reducing crop via diminished fruit-set while achieving loose clusters and better must quality, was investigated. Fruiting ‘Sangiovese’ vines grown in large pots were subjected to a pre-bloom defoliation (D) by removing the first six basal leaves from each shoot and compared to non-defoliated control (ND). Vegetative growth and grape yield and composition were assessed along with seasonal canopy net CO2 exchange rates (NCER) measured via an enclosure method. While confirming that early defoliation sharply reduced fruit set, cluster compactness and yield per shoot, the post-treament seasonal NCER/vine data were slightly higher in ND vines (13.3 μmol·s-1 vs. 12.2 μmol·s-1 recorded for D canopies). Yet, when these data were given on a per unit of area basis, defoliated vines showed higher rates than ND vines (4.75 μmol·m-2·s-1 vs. 4.16 μmol·m-2·s-1). Overall, NCER/yield (shoot basis) increased by 38 % in D vines, thus resulting in enhanced carbohydrate content for ripening; this finding accords well with advanced maturation and highly improved must soluble solids concentration. The solid physiological background of this early defoliation technique now warrants further investigation in terms of mechanical viability.
Grape production, technological parameters, and stilbenic compounds as affected by lime-induced chlorosis
Vitis vinifera L. cv. Merlot clone R3, grafted on 3309 C (lime-susceptible) rootstock, was grown in pots on a noncalcareous and a calcareous soil. The aim of the experiment was to check the effect of lime stress conditions on chlorosis, grape yield, technological parameters and stilbene (resveratrol, piceid, piceatannol, ε-viniferin) concentrations in grapes. Lime-induced chlorosis decreased grape yield per plant to a very high extent, as a result of a reduction of cluster and berry size. Technological grape parameters such as soluble solids, pH, anthocyanins, increased under lime stress over the control, whilst titratable acidity was not affected. All the tested stilbenes, being stress compounds, increased in the grapes of chlorotic vines.
Preliminary results on the effect of cluster thinning on stilbene concentration and antioxidant capacity of Vitis vinifera L. 'Barbera' wine
Research Note
Role of image-guided fine-needle aspiration biopsy in the management of patients with splenic metastasis
BACKGROUND: Splenic metastases are very rare and are mostly diagnosed at the terminal phase of the disease or at the time of autopsy. The cytohistological diagnosis, when done, is made prevalently by splenectomy. Reports on splenic percutaneous biopsies in the diagnosis of splenic metastasis are fragmentary and very poor. The aims of this study are to analyse retrospectively the accuracy, safety and the clinical impact of ultrasound (US)-guided fine-needle aspiration biopsy (UG-FNAB) in patients with suspected splenic metastasis. METHODS: A retrospective analysis of 1800 percutaneous abdominal biopsies performed at our institute during the period from 1993 to 2003 was done and 160 patients that underwent splenic biopsy were found. Among these 160 patients, 12 cases with the final diagnosis of solitary splenic metastases were encountered and they form the basis of this report. The biopsies were performed under US guidance using a 22-gauge Chiba needle. All the patients underwent laboratory tests, CT examination of the abdomen and chest, US examination of abdomen and pelvis. RESULTS: There were 5 women and 7 men, median age 65 years (range 48–80). Eight patients had a known primary cancer at the time of the diagnosis of splenic metastasis: 3 had breast adenocarcinoma, 2 colon adenocarcinoma, 2 melanoma and 1 lung adenocarcinoma. Four patients were undiagnosed at the time of the appearance of splenic metastasis and subsequent investigations showed adenocarcinoma of the lung in 2 patients and colon adenocarcinoma in the remaining 2. There was a complete correspondence between the US and Computed Tomography (CT) in detecting focal lesions of the spleen. The splenic biopsies allowed a cytological diagnosis of splenic metastasis in all the 12 patients and changed clinical management in all cases. Reviewing the 160 patients that underwent UG-FNAB of the spleen we found no complications related to the biopsies. CONCLUSION: These results indicate that UG-FNAB is a successful technique for diagnosis of splenic metastasis allowing an adequate treatment of the affected patients
Interactions between Plasmopara viticola infection and stilbene synthesis in leaves and berries of ten 'Cabernet Sauvignon' clones
Combining the knowledge that Plasmopara viticola causes considerable damages to Vitis vinifera L. worldwide production and that stilbenes have a regulatory influence on Plasmopara viticola - grapevine interaction, this study compares infection time course and stilbenes production in leaves and berries of ten different clones of 'Cabernet Sauvignon'. Following increasing infection rates, different stilbenes were produced and accumulated in leaves and berries of the same clone. Higher absolute values were found in leaves, where trans-resveratrol reaches up to 8 μg g-1 fw and ε-viniferin up to 30 μg g-1 fw while in berries, the values accumulated only up to a maximum of 3 μg g-1 fw of trans-piceid and 1,5 μg g-1 fw ε-viniferin
Uso de braquiárias para o manejo de doenças causadas por patógenos habitantes do solo.
A severidade de doenças causadas por patógenos habitantes do solo é geralmente proporcional à densidade de inóculo de seus agentes causais, como no caso do mofo branco (Sclerotinia sclerotiorum) e das podridões radiculares do feijoeiro comum, causadas por Fusarium solani e Rhizoctonia solani. As recomendações técnicas para se controlar essas doenças e minimizar seus danos envolvem a redução da população de estruturas de resistência do patógeno no solo e a formação de um ambiente desfavorável ao desenvolvimento de epidemias. Uma forma de obtenção desses benefícios é o uso de sistemas de integração lavoura-pecuária, onde espécies de gramíneas têm sido utilizadas para controle do inóculo inicial, com a recuperação da estrutura física e da comunidade microbiana no solo, entre outros fatores.bitstream/CNPAF-2010/29743/1/comt-183.pd
Age-Related Attenuation of Dominant Hand Superiority
The decline of motor performance of the human hand-arm system with age is well-documented. While dominant hand performance is superior to that of the non-dominant hand in young individuals, little is known of possible age-related changes in hand dominance. We investigated age-related alterations of hand dominance in 20 to 90 year old subjects. All subjects were unambiguously right-handed according to the Edinburgh Handedness Inventory. In Experiment 1, motor performance for aiming, postural tremor, precision of arm-hand movement, speed of arm-hand movement, and wrist-finger speed tasks were tested. In Experiment 2, accelerometer-sensors were used to obtain objective records of hand use in everyday activities
CORN DEVELOPMENT AND PRODUCTION IN FUNCTION OF SOURCES OF NITROGEN FERTILIZERS AND DOSES
Long-latency modulation of motor cortex excitability by ipsilateral posterior inferior frontal gyrus and pre-supplementary motor area
The primary motor cortex (M1) is strongly influenced by several frontal regions. Dual-site transcranial magnetic stimulation (dsTMS) has highlighted the timing of early (<40 ms) prefrontal/premotor influences over M1. Here we used dsTMS to investigate, for the first time, longer-latency causal interactions of the posterior inferior frontal gyrus (pIFG) and pre-supplementary motor area (pre-SMA) with M1 at rest. A suprathreshold test stimulus (TS) was applied over M1 producing a motor-evoked potential (MEP) in the relaxed hand. Either a subthreshold or a suprathreshold conditioning stimulus (CS) was administered over ipsilateral pIFG/pre-SMA sites before the TS at different CS-TS inter-stimulus intervals (ISIs: 40-150 ms). Independently of intensity, CS over pIFG and pre-SMA (but not over a control site) inhibited MEPs at an ISI of 40 ms. The CS over pIFG produced a second peak of inhibition at an ISI of 150 ms. Additionally, facilitatory modulations were found at an ISI of 60 ms, with supra-but not subthreshold CS intensities. These findings suggest differential modulatory roles of pIFG and pre-SMA in M1 excitability. In particular, the pIFG-but not the pre-SMA-exerts intensity-dependent modulatory influences over M1 within the explored time window of 40-150 ms, evidencing fine-tuned control of M1 output
Cognitive Control Reflects Context Monitoring, Not Motoric Stopping, in Response Inhibition
The inhibition of unwanted behaviors is considered an effortful and controlled ability. However, inhibition also requires the detection of contexts indicating that old behaviors may be inappropriate – in other words, inhibition requires the ability to monitor context in the service of goals, which we refer to as context-monitoring. Using behavioral, neuroimaging, electrophysiological and computational approaches, we tested whether motoric stopping per se is the cognitively-controlled process supporting response inhibition, or whether context-monitoring may fill this role. Our results demonstrate that inhibition does not require control mechanisms beyond those involved in context-monitoring, and that such control mechanisms are the same regardless of stopping demands. These results challenge dominant accounts of inhibitory control, which posit that motoric stopping is the cognitively-controlled process of response inhibition, and clarify emerging debates on the frontal substrates of response inhibition by replacing the centrality of controlled mechanisms for motoric stopping with context-monitoring
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