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31.
Polyamines are ubiquitous, low-molecular-weight aliphatic compounds, present in living organisms and essential for cell growth and differentiation. Copper amine oxidases (CuAOs) oxidize polyamines to aminoaldehydes releasing ammonium and hydrogen peroxide, which participates in the complex network of reactive oxygen species acting as signaling molecules involved in responses to biotic and abiotic stresses. CuAOs have been identified and characterized in different plant species, but the most extensive study on a CuAO gene family has been carried out in Arabidopsis thaliana. Growing attention has been devoted in the last years to the investigation of the CuAO expression pattern during development and in response to an array of stress and stress-related hormones, events in which recent studies have highlighted CuAOs to play a key role by modulation of a multilevel phenotypic plasticity expression. In this review, the attention will be focused on the involvement of different AtCuAOs in the IAA/JA/ABA signal transduction pathways which mediate stress-induced phenotypic plasticity events.  相似文献   
32.
The use and creation of machine-learning-based solutions to solve problems or reduce their computational costs are becoming increasingly widespread in many domains. Deep Learning plays a large part in this growth. However, it has drawbacks such as a lack of explainability and behaving as a black-box model. During the last few years, Visual Analytics has provided several proposals to cope with these drawbacks, supporting the emerging eXplainable Deep Learning field. This survey aims to (i) systematically report the contributions of Visual Analytics for eXplainable Deep Learning; (ii) spot gaps and challenges; (iii) serve as an anthology of visual analytical solutions ready to be exploited and put into operation by the Deep Learning community (architects, trainers and end users) and (iv) prove the degree of maturity, ease of integration and results for specific domains. The survey concludes by identifying future research challenges and bridging activities that are helpful to strengthen the role of Visual Analytics as effective support for eXplainable Deep Learning and to foster the adoption of Visual Analytics solutions in the eXplainable Deep Learning community. An interactive explorable version of this survey is available online at https://aware-diag-sapienza.github.io/VA4XDL .  相似文献   
33.
Anhydrous butterfat was irradiated at 6 megarads in a special glass reaction flask, and the headspace and total condensate samples were examined by wide-range (−180C to 125C) gas chromatography combined with mass spectrometry. The nature and amounts of volatile compounds were not greatly influenced by whether the butterfat was irradiated under oxygen or under vacuum, nor (apart fromn-alkanoic acids) by storage for 1 and 9 weeks. Carbon dioxide was produced in greatest amount. Of the remaining compounds, aliphatic hydrocarbons predominated both in number and amount. Aliphatic oxygenated compounds including carbonyl compounds were isolated in relatively small amounts. The following compounds were identified positively: C1–13 n-alkanes; C4–9 2-methylalkanes; C2–14 alk-l-enes; C2–9 alk-l-ynes; C2–5 n-alkanoic acids; C1–5 n-alkan-l-ols and propan-2-ol; C2–8 n-alkanals and 2-methylbut-2-enal; C3–5,7 alkan-2-ones; C1–4 n-alkyl formates, vinyl and isoamyl formate, methyl acetate and methyln-hexanoate; and carbon dioxide. Visiting Scientist from Division of Dairy Research, C.S.I.R.O., Highett, Victoria, Australia.  相似文献   
34.
DNA-encoded chemical libraries are often used for the discovery of ligands against protein targets of interest. These large collections of DNA-barcoded chemical compounds are typically screened by using affinity capture methodologies followed by PCR amplification and DNA sequencing procedures. However, the performance of individual steps in the selection procedures has been scarcely investigated, so far. Herein, the quantitative analysis of selection experiments, by using three ligands with different affinity to carbonic anhydrase IX as model compounds, is described. In the first set of experiments, quantitative PCR (qPCR) procedures are used to evaluate the recovery and selectivity for affinity capture procedures performed on different solid-phase supports, which are commonly used for library screening. In the second step, both qPCR and analysis of DNA sequencing results are used to assess the recovery and selectivity of individual carbonic anhydrase IX ligands in a library, containing 360 000 compounds. Collectively, this study reveals that selection procedures can be efficient for ligands with sub-micromolar dissociation constants to the target protein of interest, but also that selection performance dramatically drops if 104 copies per library member are used as the input.  相似文献   
35.
The X 37CrMoV5 1 KU hot working steel has been quenched and tempered, overcarburised, nitrided and nitrocarburised. The surface layers constituted after the thermochemical treatments were characterised by means of X‐ray diffraction (XRD) analyses, optical and scanning electron microscope (SEM) observations, micro‐ and macrohardness indentations. The electrochemical behaviour was evaluated in two different aggressive environments: 0.1 M Na2SO4 and 0.1 M NaCl solutions. While the overcarburised and the nitrocarburised samples exhibit a poor electrochemical behaviour, the presence of a nitrided surface layer enhances the corrosion resistance. This is attributable to the protective action of the nitrided layer that hinders the anodic dissolution reaction of the matrix, whereas the presence of complex carbides in the overcarburised or nitrocarburised samples causes the preferential dissolution of the ferritic matrix due to galvanic coupling phenomena. Finally, the poor corrosion resistance exhibited by the nitrocarburised sample can be ascribed to the presence of a large amount of ferrite together with little ε solid solution in the surface layer.  相似文献   
36.
Ordered intermetallic alloys: an assessment   总被引:2,自引:0,他引:2  
The paper summarizes our present understanding, as established at a recent workshop, of two classes of intermetallic alloys: nickel and iron aluminides, which are currently used by industries; and advanced intermetallic alloys including silicides and Laves-phase alloys, which have a great potential to be developed as new high-temperature structural materials for future industrial use. The workshop emphasized close interaction and co-operation between basic research, applied research, and industrial development, and stressed discussion of critical scientific and technological issues. The current status of these intermetallic alloys was assessed, and the directions for future research and development, as well as emerging opportunities, were identified. The information presented in the text is summarized from the presentations at the workshop, and so no references are given to the published literature. However, an extensive bibliography is appended, in which further details may be found.  相似文献   
37.
This paper describes design and test of a new impedance-measurement system for nonlinear devices that exhibits a seven-decade range and works down to a frequency of 0.01 Hz. The system is specifically designed for electrochemical measurements, but the proposed architecture can be employed in many other fields where flexible signal generation and analysis are required. The system employs an unconventional signal generator based on two pulsewidth modulation (PWM) oscillators and an autocalibration system that allows uncertainties of less than 3% to be obtained over a range of 1 k/spl Omega/ to 100 G/spl Omega/. A synchronous demodulation processing allows the noise superimposed to the low-amplitude input signals to be made negligible.  相似文献   
38.
The authors report their experience about 15 patients surgically treated for chronic large pericardial effusion; in 12 cases the etiology was malignant neoplasm, while in the other 3 cases was inflammatory disease. In 4 patients a simple subxiphoid pericardial drainage was carried out, while in the other cases a pericardial window was performed. These cases were managed using an anterior left thoracotomy in 8 patients and a videothoracoscopy in 3. The authors conclude that pericardial window with videothoracoscopic approach is the preferable procedure, but it cannot be used in every case because a lot of patients have seriously compromised conditions and the use of this technique can be hazardous.  相似文献   
39.
The influence of heat treatments on the corrosion resistance of some base-metal alloys currently used in dentistry as a base for porcelain substrate systems has been investigated. Four Co-Cr alloys (Wironit, Wironit extra hard, Wirobond and Wirolloy) and two Ni-Cr alloys (Wiron 88 and Wirolloy) were submitted to heat treatments for 30 min at 880, 980, 1080 °C for 30 min, and slowly cooled in air. The electrochemical characterization was performed by means of anodic polarization curves in Ringer's solution and artificial saliva at 37 °C. In both solutions it was found that ageing at 880 °C detrimentally affects the corrosion resistance of Co-Cr alloys; the passive zone is narrow and shows rather high current densities. On the contrary, the samples annealed at 1080 °C display a superior corrosion resistance. With Wiron 88 the effect is opposite, but the electrochemical behaviour of Wirolloy, is not affected by heat treatments; although it does have a more negative transpassive potential in artificial saliva and cannot be passivated in Ringer's solution. The SEM examination of the alloys evinces the microstructural modifications induced by heat treatments responsible for changes in the corrosion behaviour of the base-metal alloys.  相似文献   
40.
The incidence of lipomas of the colon is difficult to evaluate due to lack of symptoms. They are often discovered by chance during endoscopic or radiological examination and sometimes display only obstructive symptoms. A barium enema may be useful for the preoperative diagnosis of lipoma of the colon. The difficulty of obtaining a clear preoperative diagnosis influences the type of surgical treatment undertaken. Thus, a resection is often preferred to the simple removal of the lipoma by colotomy or endoscopy.  相似文献   
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