102 research outputs found

    Silica, Nitrogen, and Phosphorus Dynamics of Tallgrass Prairie

    Get PDF
    Experiments were conducted on big bluestem (Andropogon gerardii Vitman) 10 the greenhouse and on a tallgrass site on Konza Prairie to evaluate the effects of simulated grazing on the cycling of silica (SiO2), nitrogen, and phosphorus. Concentrations of all elements increased in vegetation that had been clipped or pruned. The absolute amount of nitrogen obtained by plants 10 the greenhouse experiment was increased by clipping foliage. Phosphorus exhibited only neutral or negative responses, while the absolute amount of silica declined in all but one experiment involving root pruning. In that experiment, the absolute amount of silica in roots was increased 25% by cutting a portion of the root system. These results suggest that the direct effects of clipping or pruning on the absolute amounts of elements cycled through vegetation are usually neutral or negative. Increased silicification or grazed foliage is suggested to be a consequence of dela.yed senescence and reduced leaf area. This interpretation provides a proximate reason why silicification is an inducible defense against herbivores

    On the Correlation Between Tactile Stimulation and Pleasantness

    Get PDF
    : several studies in the affective haptics research field showed the potential of using haptic technology to convey emotions in remote communications. In this context, it is of interest to simplify the haptic feedback without altering the informative content of the stimulus, with a two-fold advantage. on one side, it would allow the development of affective haptic devices whose technological complexity is limited, hence more compatible with wearability and portability requirements. On the other side, having a simplified set of stimuli would decrease the amount of data to be transmitted, thus improving the overall quality of remote haptic interactions. In this work, we investigated the correlation between the parameters regulating a caress-like stimulation and the perceived pleasantness. This was done by means of two experiments, in which we asked subjects to adjust the temperature and the motion velocity of a set of stimuli in order to find the most pleasant combination. results indicated that subjects preferred different values of temperature and velocity of the stimulus depending on the proposed tactile stimulation. a small difference in the pleasantness ratings was observed between caresses provided with linear movements and those given as discrete sequences of taps. In particular, participants preferred linear movements set at 34.5 °C and 3.4 cms-1. As regards caress-like stimuli provided with discrete sequences of taps, the preferred temperature and velocity were 33.2 °C and 2.9 cms-1, respectively. the presence of vibration had a little effect on the perceived pleasantness

    Let‐7a‐5p, mir‐100‐5p, mir‐101‐3p, and mir‐199a‐3p hyperexpression as potential predictive biomarkers in early breast cancer patients

    Get PDF
    Background: The aim of this study is to identify miRNAs able to predict the outcomes in breast cancer patients after neoadjuvant chemotherapy (NAC). Patients and methods: We retrospec-tively analyzed 24 patients receiving NAC and not reaching pathologic complete response (pCR). miRNAs were analyzed using an Illumina Next‐Generation‐Sequencing (NGS) system. Results: Event‐free survival (EFS) and overall survival (OS) were significantly higher in patients with up-regulation of let‐7a‐5p (EFS p = 0.006; OS p = 0.0001), mirR‐100‐5p (EFS s p = 0.01; OS p = 0.03), miR‐ 101‐3p (EFS p = 0.05; OS p = 0.01), and miR‐199a‐3p (EFS p = 0.02; OS p = 0.01) in post‐NAC samples, independently from breast cancer subtypes. At multivariate analysis, only let‐7a‐5p was significantly associated with EFS (p = 0.009) and OS (p = 0.0008). Conclusion: Up‐regulation of the above miRNAs could represent biomarkers in breast cancer

    Predictive factors of antiproliferative activity of octreotide LAR as first-line therapy for advanced neuroendocrine tumours

    Get PDF
    background: The antiproliferative activity of octreotide LAR in neuroendocrine tumours (NETs) has been demonstrated by small retrospective studies and confirmed by a prospective phase III trial (PROMID). However, there are limited data about the duration and predictors of response. The aim of our retrospective study was to determine the time to radiological progression (TTRP) of disease and the factors that were associated with better response. methods: A total of 254 treatment naïve patients with advanced NETs and positive somatostatin receptor scintigraphy were included. Mean follow-up period was 42 months. results: The location of primary was in the small bowel in 204, pancreas in 22, lungs in 14, rectum in 7 and unknown in 7 patients. Most tumours were well-differentiated, G1 (58%) and G2 (23%). The majority of patients commenced octreotide LAR due to functional symptoms (57%), radiological progression (10%) or in the presence of asymptomatic and stable disease on the basis of data from the PROMID trial (18.5%). Partial response occurred in 5%. For all patients, the median TTRP was 37 months (95% confidence interval, CI: 32–52 months). There was a statistically significant shorter TTRP in patients with pancreatic tumours, liver metastases and intermediate grade tumours. Extremely raised (>10 times the upper limit of normal) baseline chromogranin A levels were associated with an unfavourable outcome. In contrast, male sex, carcinoid heart disease and initiation of treatment in the presence of stable disease were predictive of a better response. Age, extra-hepatic metastases, presence of mesenteric desmoplasia, previous resection and functional status of the primary tumour did not affect response. conclusions: The duration of the antiproliferative effect of octreotide LAR seems to be longer than previously reported. This study has identified several predictors of response in a large cohort of patients with NETs on somatostatin analogue therapy

    Italian Association of Clinical Endocrinologists (AME) position statement: a stepwise clinical approach to the diagnosis of gastroenteropancreatic neuroendocrine neoplasms

    Get PDF

    Application of smart strategies against severe dynamic actions

    No full text
    The research described in this paper on the application of active and semi-active structural control in the protection of structures against severe dynamic actions aims at demonstrating the effectiveness of these techniques and also the importance of the use of smart devices. These special devices need a robust control law which should permit to exploit all their innovative performance characteristics. In the paper a study concerning a comparison among different control approaches is presented: the cases of mass damping system and coupled structures are analyzed. Also, some hints for device design are given. In the examined models a wide simulation analysis has shown the achievement of a very satisfying performance. The research results demonstrate that semi-active control based on smart devices and a proper algorithm offer the reliability of purely passive systems, keeping however both capabilities and flexibility of fully active systems
    corecore