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71.
Ettore Pozzo 《Materials and Structures》1987,20(4):303-314
This research investigates the post-elastic behaviour of reinforced concrete members under combined bending and axial loads,
considering different concrete strengths and types, reinforcing percentages (always symmetric), axial loads and loading rates.
Sensible differences between experimental results, for usual and high test loading rates, and those obtained by ‘classical’
analysis are pointed out. One of the most interesting results shows that disagreement was reduced (to low quotas for not high
axial loads) if we took into account certain phenomena neglected by theory (such as tensile strength of concrete, tension
stiffening and the effect in reinforcement strength of transverse constraint caused by the presence of concrete) while structural
ductility values appeared fairly probative, at least with the conventional collapse assumed.
The strong decreases that ductility can undergo with increasing loading rate are also pointed out, indicating that it is therefore
hazardous to utilize results obtained with usual test procedures in the seismic field.
Work carried out at CESMACOS (Materials and Structures Experimentation Centre), Cagliari, directed by the author. 相似文献
72.
Dr. Sergio Valente Dr. Daniela Trisciuoglio Dr. Maria Tardugno Dr. Rosaria Benedetti Dr. Donatella Labella Prof. Daniela Secci Dr. Ciro Mercurio Dr. Roberto Boggio Dr. Stefano Tomassi Dr. Salvatore Di Maro Prof. Ettore Novellino Prof. Lucia Altucci Dr. Donatella Del Bufalo Prof. Antonello Mai Dr. Sandro Cosconati 《ChemMedChem》2013,8(5):800-811
Herein we report novel pyrrole‐ and benzene‐based hydroxamates ( 8 , 10 ) and 2′‐aminoanilides ( 9 , 11 ) bearing the tert‐butylcarbamate group at the CAP moiety as histone deacetylase (HDAC) inhibitors. Compounds 8 b and 10 c selectively inhibited HDAC6 at the nanomolar level, whereas the other hydroxamates effected an increase in acetyl‐α‐tubulin levels in human acute myeloid leukemia U937 cells. In the same cell line, compounds 8 b and 10 c elicited 18.4 and 21.4 % apoptosis, respectively (SAHA: 16.9 %), and the pyrrole anilide 9 c displayed the highest cytodifferentiating effect (90.9 %). In tests against a wide range of various cancer cell lines to determine its antiproliferative effects, compound 10 c exhibited growth inhibition from sub‐micromolar (neuroblastoma LAN‐5 and SH‐SY5Y cells, chronic myeloid leukemia K562 cells) to low‐micromolar (lung H1299 and A549, colon HCT116 and HT29 cancer cells) concentrations. In HT29 cells, 10 c increased histone H3 acetylation, and decreased the colony‐forming potential of the cancer cells by up to 60 %. 相似文献
73.
Castiglioni S Bagnati R Melis M Panawennage D Chiarelli P Fanelli R Zuccato E 《Water research》2011,45(16):5141-5150
The most relevant human urinary metabolites of cocaine (nine metabolites) were measured in urban wastewater in Italy and USA. A novel analytical method based on liquid chromatography tandem mass spectrometry allowed the identification of ecgonine, ecgonine methyl ester and the pyrolytic derivatives of cocaine in untreated wastewater. The aim of this study was to verify whether the pattern of cocaine metabolites in wastewater reflected the human excretion profile in urine. The performance of the method was good, with recoveries higher than 60% and limits of quantifications in the low ng/L range. The stability in untreated wastewater was assessed for all metabolites and the best storage condition resulted freezing samples immediately after collection and keep them frozen until analysis. All the selected compounds were measured in wastewater at concentrations up to 1.5 μg/L and their weekly loads were calculated during a five weeks monitoring campaign in Milan (Italy). The profiles of cocaine metabolites in wastewater matched with those in human urine reported in the literature, suggesting that measures in wastewater reflect the real human excretion and that wastewater analysis is suitable for assessing drug consumption. Benzoylecgonine was confirmed as the best target for estimating cocaine use by wastewater analysis, while cocaine itself should not be considered because its amount in wastewater is affected by other environmental sources such as transport, handling and consumption. Results suggested that the measurement of other metabolites in combination with benzoylecgonine might reflect 60% of an administered dose of cocaine providing also information on different patterns of use. 相似文献
74.
Chiara Platella Rosa Gaglione Ettore Napolitano Angela Arciello Valentina Pirota Filippo Doria Domenica Musumeci Daniela Montesarchio 《International journal of molecular sciences》2021,22(19)
G-quadruplex existence was proved in cells by using both antibodies and small molecule fluorescent probes. However, the G-quadruplex probes designed thus far are structure- but not conformation-specific. Recently, a core-extended naphthalene diimide (cex-NDI) was designed and found to provide fluorescent signals of markedly different intensities when bound to G-quadruplexes of different conformations or duplexes. Aiming at evaluating how the fluorescence behaviour of this compound is associated with specific binding modes to the different DNA targets, cex-NDI was here studied in its interaction with hybrid G-quadruplex, parallel G-quadruplex, and B-DNA duplex models by biophysical techniques, molecular docking, and biological assays. cex-NDI showed different binding modes associated with different amounts of stacking interactions with the three DNA targets. The preferential binding sites were the groove, outer quartet, or intercalative site of the hybrid G-quadruplex, parallel G-quadruplex, and B-DNA duplex, respectively. Interestingly, our data show that the fluorescence intensity of DNA-bound cex-NDI correlates with the amount of stacking interactions formed by the ligand with each DNA target, thus providing the rationale behind the conformation-sensitive properties of cex-NDI and supporting its use as a fluorescent probe of G-quadruplex structures. Notably, biological assays proved that cex-NDI mainly localizes in the G-quadruplex-rich nuclei of cancer cells. 相似文献
75.
Identification of the pharmaceuticals for human use contaminating the Italian aquatic environment 总被引:7,自引:0,他引:7
A predictive approach seems useful to identify pharmaceuticals in the environment and give an idea of overall levels of contamination, so as to restrict monitoring to those molecules most likely to be contaminants. We propose an approach based on two parts. The first is to rank the molecules according to the predicted environmental loads; the second is to refine the list by analysing the pharmaceuticals in sewage treatment plants (STPs) and comparing the concentrations with levels previously measured in surface water. This approach identified a restricted group of priority pollutants (ofloxacin, furosemide, atenolol, hydrochlorothiazide, carbamazepine, ibuprofen, spiramycin, bezafibrate, erythromycin, lincomycin and clarithromycin) in the aquatic environment in Italy, for further studies and monitoring. 相似文献
76.
Pietro Locantore Rosa Maria Paragliola Gianluca Cera Roberto Novizio Ettore Maggio Vittoria Ramunno Andrea Corsello Salvatore Maria Corsello 《International journal of molecular sciences》2022,23(12)
Cushing’s disease represents 60–70% of all cases of Cushing’s syndrome, presenting with a constellation of clinical features associated with sustained hypercortisolism. Molecular alterations in corticotrope cells lead to the formation of ACTH-secreting adenomas, with subsequent excessive production of endogenous glucocorticoids. In the last few years, many authors have contributed to analyzing the etiopathogenesis and pathophysiology of corticotrope adenomas, which still need to be fully clarified. New molecular modifications such as somatic mutations of USP8 and other genes have been identified, and several case series and case reports have been published, highlighting new molecular alterations that need to be explored. To investigate the current knowledge of the genetics of ACTH-secreting adenomas, we performed a bibliographic search of the recent scientific literature to identify all pertinent articles. This review presents the most recent updates on somatic and germline mutations underlying Cushing’s disease. The prognostic implications of these mutations, in terms of clinical outcomes and therapeutic scenarios, are still debated. Further research is needed to define the clinical features associated with the different genotypes and potential pharmacological targets. 相似文献
77.
复杂网络理论从结构性视角对电网安全进行分析。然而,当前多数文献使用的纯拓扑的研究方法无法体现电力系统特有的物理特性。文中讨论了电网运行状态和电网结构这2个不同的电网安全因素的相互关系,并指出电网安全指标应既能保持复杂网络理论在结构性分析方面的优势,又能够体现电力系统的特有属性。在网络能力和熵度的基础上,进一步提出了母线... 相似文献
78.
Ettore Settanni Linda B. Newnes Nils E. Thenent Daniel Bumblauskas Glenn Parry Yee Mey Goh 《Quality and Reliability Engineering International》2016,32(4):1553-1580
Under incentivized contractual mechanisms such as availability‐based contracts, the support service provider and its customer must share a common understanding of equipment reliability baselines. Emphasis is typically placed on the information technology‐related solutions for capturing, processing and sharing vast amounts of data. In the case of repairable fielded items, scant attention is paid to the pitfalls within the modelling assumptions that are often endorsed uncritically and seldom made explicit during field reliability data analysis. This paper presents a case study in which good practices in reliability data analysis are identified and applied to real‐world data with the aim of supporting the effective execution of a defence avionics availability‐based contract. The work provides practical guidance on how to make a reasoned choice between available models and methods based on the intelligent exploration of the data available in practical industrial applications. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
79.
Pedretti E Traub WA Monnier JD Millan-Gabet R Carleton NP Schloerb FP Brewer MK Berger JP Lacasse MG Ragland S 《Applied optics》2005,44(25):5173-5179
We describe the fringe-packet tracking system used to equalize the optical path lengths at the Infrared Optical Telescope Array interferometer. The measurement of closure phases requires obtaining fringes on three baselines simultaneously. This is accomplished by use of an algorithm based on double Fourier interferometry for obtaining the wavelength-dependent phase of the fringes and a group-delay tracking algorithm for determining the position of the fringe packet. A comparison of data acquired with and without the fringe-packet tracker shows a factor of approximately 3 reduction of the error in the closure-phase measurement. The fringe-packet tracker has been able so far to track fringes with signal-to-noise ratios as low as 1.8 for stars as faint as mH = 7.0. 相似文献
80.
Measuring and predicting environmental concentrations of pesticides in air after application to paddy water systems 总被引:1,自引:0,他引:1
In this study, the volatilization of five pesticides applied to an artificial flooded paddy field was assessed using the theoretical profile shape (TPS) and the integrate horizontal flux (IHF) techniques. The dataset derived was utilized to improve the volatilization routine of the rice water quality (RICEWQ) model. The masses of pesticides ethoprophos, procymidone, metalaxyl, chlorpyrifos, and chlorpyrifos methyl volatilized from paddy water and their concentrations in paddy water were determined for a period of 6 d after application. The highest and lowest volatilization losses were observed for chlorpyrifos and metalaxyl, respectively, accounting for 3.3% and 0.03% of their initially applied amount. A rapid pesticide dissipation was evident in paddy water during the study period. The RICEWQ model was used to simulate the fate of pesticides in the artificial paddy system. The Kvolat, an empiric coefficient used by the model as an input parameter, was calculated for all pesticides through model calibration. RICEWQ simulated well the fate of pesticides in paddy water. A significant regression correlation between Henry's law constant (Hk) and Kvolat of the studied compounds was established which could facilitate the parametrization of the model for describing pesticide volatilization. 相似文献