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61.
Raviduth Ramful Thefye P. M. Sunthar Elia Marin Wenliang Zhu Giuseppe Pezzotti 《Materials》2022,15(4)
Treatment modification to improve the durability of bamboo against biotic and abiotic factors often results in adverse effects to its mechanical properties due to changes in hygroscopic characteristics. This study aims at exploring in more detail, the effect of treatment modification, in particular smoke treatment, on the hygroscopic nature of bamboo. In the first part of this study, changes to its chemical structure were investigated by Raman and Fourier-transform infrared (FTIR) spectroscopic techniques. From Raman analysis, specific bands attributed to lignin component in bamboo, namely at 1600 cm−1 and 1632 cm−1, which varied in intensities among treated and untreated specimens, could be considered to assess the extent of treatment modification. Besides, FTIR results showed that the chemical constituents of bamboo inner and outermost surfaces vary extensively with distinctive changes during treatment modification. The steam component in smoke treatment is assumed to cause a slight increase in the moisture content in the outermost surface of smoked bamboo as evidenced by FTIR results. In addition, the hydrophobic surface of smoked bamboo, which was affected during smoke treatment modification due to superior mean roughness parameter in its outermost surface, impacted its water-repelling ability. From FTIR results, an increase in lignin in bamboo was confirmed at peak 1114 cm−1, which occurred as a result of thermal effect above a temperature of 100 °C leading to poly-condensation reactions. The increase in lignin is assumed to cause an overall increase in hardness of smoked bamboo which was found to be two-fold higher when compared with the untreated ones. The approach of this research investigation, which has shown the benefit of using spectroscopic techniques to monitor and understand the changes in the hygroscopic nature of bamboo surfaces, can likewise be considered to predict the corresponding effects of treatment modification or degradation on the mechanical properties of natural materials. 相似文献
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Nociceptive stimuli can induce a transient suppression of electroencephalographic oscillations in the alpha frequency band (ie, alpha event-related desynchronization, α-ERD). Here we investigated whether α-ERD could be functionally distinguished in 2 temporally and spatially segregated subcomponents as suggested by previous studies. In addition, we tested whether the degree of dependence of nociceptive-induced α-ERD magnitude on the prestimulus α-power would have been larger than the degree of dependence on the poststimulus α-power. Our findings confirmed the dissociation between a sensory-related α-ERD maximally distributed over contralateral central electrodes, and a task-related α-ERD (possibly affected by motor-related activity), maximally distributed at posterior parietal and occipital electrodes. The cortical sources of these activities were estimated to be located at the level of sensorimotor and bilateral occipital cortices, respectively. Importantly, the time course of the α-ERD revealed that functional segregation emerged only at late latencies (400 to 750 ms) whereas topographic similarity was observed at earlier latencies (250 to 350 ms). Furthermore, the nociceptive-induced α-ERD magnitude was significantly more dependent on prestimulus than poststimulus α-power. Altogether these findings provide direct evidence that the nociceptive-induced α-ERD reflects the summation of sensory-related and task-related cortical processes, and that prestimulus fluctuations can remarkably influence the non-phase-locked nociceptive α-ERD.PerspectivePresent results extend the functional understanding of α-oscillation suppression during pain perception and demonstrate the influence of prestimulus variability on this cortical phenomenon. This work has the potential to guide pain clinicians in a more accurate interpretation on physiological and psychological modulations of α-oscillations. 相似文献
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Vincenzo Duino Luigi Fiocca Giuseppe Musumeci Emilia D’Elia Mauro Gori Elisa Cerchierini Orazio Valsecchi Michele Senni 《Medicine》2015,94(20)
Functional mitral regurgitation (FMR) is frequent in patients with heart failure (HF). It develops as a consequence of left ventricle (LV) geometry alterations, causing imbalance between increased tethering forces and decreased closing forces exerted on the mitral valve apparatus during systole.FMR is known to change at rest and during effort, due to preload–afterload changes, myocardial ischemia, and/or LV dysfunction. Despite optimized medical therapy, an FMR can be responsible of shortness of breath limiting quality of life and decompensation. In this report, we present a case of dynamic FMR treated with MitraClip.MitraClip implantation is a successful and innovative opportunity for HF patients with FMR. 相似文献
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Susanna Esposito Paola Marchisio Annalisa Orenti Silvia Spena Sonia Bianchini Erica Nazzari Chiara Rosazza Alberto Zampiero Elia Biganzoli Nicola Principi 《Medicine》2015,94(42)
Evaluation of the genetic contribution to the development of recurrent acute otitis media (rAOM) remains challenging. This study aimed to evaluate the potential association between single nucleotide polymorphisms (SNPs) in selected genes and rAOM and to analyze whether genetic variations might predispose to the development of complicated recurrent cases, such as those with tympanic membrane perforation (TMP).A total of 33 candidate genes and 47 SNPs were genotyped in 200 children with rAOM (116 with a history of TMP) and in 200 healthy controls.INFγ rs 12369470CT was significantly less common in the children with rAOM than in healthy controls (odds ratio [OR] 0.5, 95% confidence interval [CI] 0.25–1, P = 0.04). Although not significant, interleukin (IL)-1β rs 1143627G and toll-like receptor (TLR)-4 rs2737191AG were less frequently detected in the children with rAOM than in controls. The opposite was true for IL-8 rs2227306CT, which was found more frequently in the children with rAOM than in healthy controls. The IL-10 rs1800896TC SNP and the IL-1α rs6746923A and AG SNPs were significantly more and less common, respectively, among children without a history of TMP than among those who suffered from this complication (OR 2.17, 95% CI 1.09–4.41, P = 0.02, and OR 0.42, 95% CI 0.21–0.84, P = 0.01).This study is the first report suggesting an association between variants in genes encoding for factors of innate or adaptive immunity and the occurrence of rAOM with or without TMP, which confirms the role of genetics in conditioning susceptibility to AOM. 相似文献
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Silvia Miano Oliviero Bruni Vincenzo Leuzzi Maurizio Elia Elisabetta Verrillo Raffaele Ferri 《Clinical neurophysiology》2004,115(4):938-945
OBJECTIVE: Sleep disturbances are frequent in Angelman syndrome (AS); however, beside the few studies which have investigated sleep disorders in AS by means of questionnaires, to our knowledge, no systematic polysomnographic recordings have been carried out in AS patients. The present study represents the first attempt to study sleep patterns of AS by polysomnography, to evaluate the influences of sleep on the paroxysmal electroencephalogram (EEG) patterns of AS and to assess the eventual age-related changes of sleep architecture and of sleep EEG abnormalities in children and adolescents with AS. METHODS: Fifteen children with AS (7 males and 8 females, mean age 7.2 years, range 3-16 years), attending the Sleep Center of the Department of Child Neurology and Psychiatry of the University of Rome 'La Sapienza' and the Sleep Research Centre of the Oasi Institute (IRCCS) of Troina were included and subdivided into two subgroups by age: subgroup 1, aged 3-5 years, and subgroup 2, aged 9-17 years. Two control groups of age-matched normal subjects were also included: one aged less than 8 years and another aged more than 8 years; additionally, two other groups of age-matched children with epilepsy and mental retardation of different origin, one aged less and one aged more than 9 years were taken into consideration. The statistical comparison between the sleep parameters obtained from the patients and those from the other groups was carried out by means of the non-parametric Kruskal-Wallis ANOVA and the Mann-Whitney U test. RESULTS: The most frequent EEG abnormality found in AS patients appeared to be the 2-3 c/s poorly defined spike/waves complexes. This pattern was influenced by sleep stages; the duration of the runs showed an increasing length with sleep deepening from sleep stage 1 to slow-wave sleep (SWS). Moreover, the 2-3 c/s bursts activity present in sleep stage 2 showed a slowing to 1-2 c/s during SWS. Regarding sleep architecture, in subjects with AS aged <8 year there was a significant reduction in sleep efficiency as compared to normal controls, while the percentage and duration of REM sleep was significantly lower and the percentage of SWS was significantly higher. REM sleep time was reduced in AS subjects aged >8 years than in normal controls. The comparison between AS groups and mental retardation with epilepsy groups did not show significant differences. CONCLUSIONS: Similarly to other types of genetically determined mental retardation syndromes, also subjects with AS seems to show important abnormalities of their sleep polysomnographic patterns. SIGNIFICANCE: This is the first study which reports, in detail, these abnormalities and opens a new path for further insight into the knowledge of additional sleep-related disturbances which are reported in sleep questionnaires by the caregivers of AS subjects. 相似文献
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Albayrak Merve Figueras Carolina Seguí Elia Campolo Michela Gabarrón Eva Moreno Reinaldo Maurel Joan Casanova-Molla Jordi 《Journal of neurology》2022,269(8):4174-4184
Journal of Neurology - Oxaliplatin-induced neuropathy (OIN) implies axonal damage of both small and large sensory nerve fibers. We aimed at comparing the neurophysiological changes occurred after... 相似文献
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