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211.
In several policy documents bioenergy is recognized as an important renewable energy source in Italy. The increase in energy prices represents an opportunity for lignocellulosic energy crops such as acacia and poplar. 相似文献
212.
213.
Peter Kirbiš Ivan Anžel Mihael Brunčko 《The Physics of Metals and Metallography》2016,117(11):1092-1100
Phase transformations have been studied in a variety of different steels with the use of “in situ” electrical resistance measurements. The results were evaluated by metallography of the initial and final microstructures and with consideration of data from the published literature. On this basis a good correlation has been established and it was shown that this method is suitable for such investigations. It even presents certain advantages, thus providing a more complete understanding of the physical metallurgy of steels. We out-lined the field in which the measurement of electrical resistance is particularly suitable and an example of processes that are difficult to monitor using other commonly used methods. 相似文献
214.
215.
C.Vernozy Rozand C. Mazuy G. Perrin F. Haond M. Bes Y. Brun J. Fleurette 《International journal of food microbiology》1996,30(3):373-378
One hundred and ninety strains of coagulase-negative staphylococci were isolated from goat's milk, whey and cheese at various stages of manufacture.
Sixteen different coagulase negative Staphylococci (CNS) species were recovered, 3 of which were predominant: Staphylococcus simulans, Staphylococcus epidermidis and Staphylococcus xylosus.
The prevalent species were recovered at least at two different stages of cheese manufacturing, suggesting a better adaptation to the environment. After 15 days of ripening, the cheeses showed lower counts of Micrococcaceae. 相似文献
216.
Ruda GF Nguyen C Ziemkowski P Felczak K Kasinathan G Musso-Buendia A Sund C Zhou XX Kaiser M Ruiz-Pérez LM Brun R Kulikowski T Johansson NG González-Pacanowska D Gilbert IH 《ChemMedChem》2011,6(2):309-320
2'-Deoxyuridine triphosphate nucleotidohydrolase (dUTPase) is a potential drug target for the treatment of malaria. We previously reported the discovery of 5'-tritylated analogues of deoxyuridine as selective inhibitors of this Plasmodium falciparum enzyme. Herein we report further structure-activity studies; in particular, variations of the 5'-trityl group, the introduction of various substituents at the 3'-position of deoxyuridine, and modifications of the base. Compounds were tested against both the enzyme and the parasite. Variations of the 5'-trityl group and of the 3'-substituent were well tolerated and yielded active compounds. However, there is a clear requirement for the uracil base for activity, because modifications of the uracil ring result in loss of enzyme inhibition and significant decreases in antiplasmodial action. 相似文献
217.
Diana P Stagno A Barraja P Carbone A Parrino B Dall'Acqua F Vedaldi D Salvador A Brun P Castagliuolo I Issinger OG Cirrincione G 《ChemMedChem》2011,6(7):1291-1299
Despite improvements in the treatment and prevention of cancer, the number of new diagnoses continues to rise; this has fuelled substantial interest in the development of new and effective chemotherapeutic agents. Compounds of the triazene class, such as dacarbazine, have been used in the clinical management of many cancer types including brain, leukemia, and melanoma. A new compound class bearing a triazenoazaindole scaffold was synthesized with the aim of identifying new antiproliferative agents. Compounds 5a-g and 6a-c were screened against a panel of human tumor cell lines, and two of them, 5e and 5f, showed cytotoxicity (GI(50) range: 2.2-8.2 μM) in all cell lines. These two compounds even maintained their cytotoxicity in some multidrug-resistant cell lines. Flow cytometry analysis demonstrated their ability to induce cell death by apoptosis with involvement of lysosomes. 相似文献
218.
Hampton SE Baragaña B Schipani A Bosch-Navarrete C Musso-Buendía JA Recio E Kaiser M Whittingham JL Roberts SM Shevtsov M Brannigan JA Kahnberg P Brun R Wilson KS González-Pacanowska D Johansson NG Gilbert IH 《ChemMedChem》2011,6(10):1816-1831
Deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) is a potential drug target for malaria. We previously reported some 5'-tritylated deoxyuridine analogues (both cyclic and acyclic) as selective inhibitors of the Plasmodium falciparum dUTPase. Modelling studies indicated that it might be possible to replace the trityl group with a diphenyl moiety, as two of the phenyl groups are buried, whereas the third is exposed to solvent. Herein we report the synthesis and evaluation of some diphenyl analogues that have lower lipophilicity and molecular weight than the trityl lead compound. Co-crystal structures show that the diphenyl inhibitors bind in a similar manner to the corresponding trityl derivatives, with the two phenyl moieties occupying the predicted buried phenyl binding sites. The diphenyl compounds prepared show similar or slightly lower inhibition of PfdUTPase, and similar or weaker inhibition of parasite growth than the trityl compounds. 相似文献
219.
Twelve low-rise shear walls, with the same aspect ratio of 0.4 but with different structural parameters including the design frequency, reinforcement ratio and normal force, have been submitted to pseudo-dynamic (PSD) tests conducted at the ELSA laboratory of the Joint Research Centre. The focus of this testing campaign was to study the engineering margin for shear walls depending on the relative position of their structural frequency with respect to the excitation peak. After presenting the parameters of the PSD tests, three methods for identifying the structural frequency drift observed as damage occurs have been used in this paper: a numerical identification from a nonlinear pushover analysis, and two methods from experimental data, a system identification method based on an error output model and a more direct identification method based on the secant stiffness of force-displacement cycles. For each shear wall, a relationship f(X) between the structural frequency and the maximum of the top-displacement is derived from the previous methods and the consistency between the three approaches has been checked. Finally, these f(X) curves have been employed in a single degree of freedom model for predicting time-history top-displacements. The predictions turn out to be quite satisfactory, in particular when f(X) relationship is identified by the error output model. 相似文献
220.
It has been well documented that the medial parvocellular subnucleus of the hypothalamic paraventricular nucleus (PVN) participates in immune regulation by releasing corticotrophin-releasing hormone (CRH), which triggers the hypothalamus-pituitary-adrenal axis, leading to immunosuppression. Little is known about other possible influences of PVN on immunomodulation. Evidence, however, has been accumulating recently, indicating possible involvement of other subnuclei of this nucleus. By using the c-fos technique, the present study investigated the neuronal groups of the PVN that were activated in response to intracerebroventricularly administered IL-1 beta. In addition to strong Fos expression in the dorsal part of medial parvocellular subnucleus of the PVN, where CRH neurons are located, two more neuronal groups were found to express Fos protein. One of which was the oxytocin-immunoreactive magnocellular neurons, mainly concentrated in the anterior and medial magnocellular subnuclei of the PVN. The magnocellular PVN subnuclei are known to project to, and release their hormones, in the posterior pituitary. Another group of Fos-immunoreactive neurons were found in the brainstem and spinal cord projecting area of the PVN. By combining retrograde tracing technique and Fos immunohistochemistry, it was proved that many of the spinal cord projecting PVN neurons were activated following IL-1 beta administration, through which the spinal cord sympathetic outflow might be regulated. The present study indicates that the hypothalamic PVN may serve as an integrative center for immunomodulation via three channels, i.e., the CRH and oxytocin neuroendocrinological and the PVN-spinal cord sympathetic neural channels. 相似文献