968 resultados para Bellini, Vincenzo, 1801-1835.


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Historical sources of the late-18th and 19th centuries were searched for information on coastal weather conditions in Southern California. Relatively calm winters until 1828 were followed by unusually stormy winters from about 1829 to 1839. Later periods were again predominantly calm, with notable exceptions related to the ENSO events of 1845 and 1878. Following decreases through the stormy 1830s, sizes of kelp forests appear to have rebounded in the 1840s. ENSO occurrences and eruption of the volcano Cosiguina in 1835 are likely causes for changing wind patterns. Our results link the unique AD 1840 Macoma leptonoidea pelecypod shell layer in laminated Santa Barbara Basin sediment ("Macoma event") to abruptly changing oceanographic and weather patterns.

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Catch length-frequency data of Otolithes ruber (Schneider, 1801) obtained from the "Projecto de Pesca Experimental da RDA" on Sofala Bank, Mozambique, in 1987 were used to estimate growth parameters, mortalities and exploitation rates. The yield-and biomass-per-recruit analyses based thereon suggest that the stock is overfished.

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本发明提供一种治疗艾滋病的药物组合物,其中含有治疗艾滋病有效量的式(I)化合物联苯环辛二烯类木脂素(+)-戈米辛 K3[(+)-gomisin K3]及可药用载体和/或赋形剂。该药物组合物通过抑制逆转录酶和蛋白酶活性的作用机制,从而达到抑制HIV-1病毒的增殖。本发明同时给出了该药物组合物的制备方法,及其在制备逆转录酶抑制剂药物和在制备抗艾滋病药物中的应用。

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A total of 592 individuals of Loligo brasiliensis from the Mar del Plata coastal fishing area (Buenos Aires prov., Argentina) have been studied during the 1961-1964 period. From a morphological point of view the population appears to be uniform and homogeneus. A brief description of this species is given in this paper since references in the literature are scarce from the time at which Blainville (1923) first described it. The only further references are found in D'Orbigny (1835), and Ferrusac (1839), and in Hoyle (1886), and Tyron Pilsbry (1879). In this paper the species was mentioned only as a bibliographical reference on morphological or biological conditions has been found in the literature. The distribution of this species ranges from Cuba, Brazil, Uruguay to the Argentine coast, probably down to the Gulf of San Jorge. The samples had been studied with respect to various body measurements by classifing the individuals in total length classes, since body length was considered the most significant measurement. The condition factor K has been calculated for different sexes and ages, for the various length classes. The results lead to the conclusion that the smaller the length the higher is the value obtained for K and viceversa. This is due to the fact that the length of the tentacle increases considerably with increasing size. Since the tentacle are quite light the factor K diminishes accordingly. The condition factor increases considerably from December to April with an average of 0.42, decrease and becomes stable from March to October, with an average of 0.30. This is a consequence of the ripening of the sex glands. The sex-ratios are as following: year 1961, 42 % female, 42 % male; year 1962, 51 % female, 45 % male; year 1963, 46 % female, 53 % male; year 1964, 26 % female, 42 % male, 32 % indif. The great percentage of 72 undifferentiated young individuals in the 1964 (March) sampling increases the ratio of undifferentiation. A short morphological description of both ovules and spermatozoos is given. An examination of the sex glands leads to the following conclusions: a) male and female sex gland in a preparatory stage during the whole year; b) the highest percentage of ripe glands is found through, November-March; e) the spawning appears to precede rather slowly, but this certain since the spawning environment does not coincide with the natural habitat of the species. Few spawning individuals were found; d) sexual differentiation begins at body lenght from 30 to 40 mm; i.e. a total length of approximately 145 mm. At a body length of 70 mm. the hectocotilication (sexual character) begins to appear. In June 1962, a sample gathered at Rawson (Chubut) was analyzed. The conclusion was reached that the sex glands in this population are in an earlier stage of development in comparison with those from the Mar del Plata area. Also the average for the factor K which were found to be 0.17 for females and 0.19 for male, are rather low for that date. These physiological facts are possibly related to morphological differences which will be pointed out in a forthcoming publication. Some very typical associations with Artemesia longinaris and Percophis brasiliensis were found. Cannibalism has been observed.

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We consider finite-horizon LQR control with limited controller-system communication. Within a time-horizon T , the controller can only communicate with the system d

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We demonstrate a stretched contact-printing technique to assemble one-dimensional nanostructures with controlled density and orientation. Over 90% nanowires are highly aligned along the primary stretching direction. Specifically, The hybrid inorganic-organic TFTs based on a parallel-aligned nanowire network and a semiconducting polymer reveal a significant positive enhancement in transistor performance and air-stability.

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Cathepsin B is a lysosomal cysteine protease of the papain-like enzyme family with multiple biological functions. In this study, Paralichthys olivaceus cathepsin B (PoCatB) cDNA was isolated from flounder embryonic cells (FEC) treated with UV-inactivated grass carp hemorrhage virus (GCHV) and subsequently identified as a vitally induced gene. The full length cDNA of PoCatB is 1801 bp encoding 330-amino acids. The deduced protein has high homology to all known cathepsin B proteins, containing an N-terminal signal peptide, cysteine protease active sites, the occluding loop segment and a glycosylation site, all of which are conserved in the cathepsin B family. PoCatB transcription of FEC cells could be induced by turbot (Scophthalmus maximus) rhabdovirus (SMRV), UV-inactivated SMRV, UV-inactivated GCHV, poly I:C or lipopolysaccharide (LPS), and SMRV or poly I:C was revealed to be most effective among the five inducers. In normal flounder, PoCatB mRNA was detectable in all examined tissues. Moreover, SMRV infection could result in significant upregulation of PoCatB mRNA, predominantly in spleen, head kidney, posterior kidney, intestine, gill and muscle with 18.2,10.9, 24.7,12, 31.5 and 18 fold increases at 72 h post-infection respectively. These results provided the first evidence for the transcriptional induction of cathepsin B in fish by virus and LPS, indicating existence of a novel function in viral defense. (C) 2008 Elsevier Ltd. All rights reserved.

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The growth and characterization of quantum cascade (QC) lasers based on InGaAs/InAlAs material system are investigated. Pronounced intersubband absorption from stacked active region of QC structure is used to monitor the wavelength of QC laser and disclose the material quality. The precise control of the epilayer thickness and the good quality of interfaces are demonstrated by the abundant narrow satellite peaks of X-ray diffraction. Laser action in quasi-continuous wave operation is achieved at lambda approximate to 5.1-5.2 mum up to 300 K. For 10 x 800 mum(2) laser device, peak output power of similar to7.2 mW and threshold current density of 3 kA/cm(2) at room temperature are obtained. For some devices, if keep the peak output powers at the similar to2 mW level, quasi-continuous wave operation at room temperature persists more than 1 h are recorded. (Q) (C) 2001 Elsevier Science Ltd. All rights reserved.

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We report a LD side-pumped fundamental-mode (Mx(2) = 1.35 and My(2) = 1.27) passive Q-switched and mode-locked Nd:YAG laser based on a semiconductor saturable absorber mirror (SESAM). At a pump current of 12.5 A, the average output power of 5.68 W with 80 kHz repetition rate and 2 mu s pulse width of the Q-switched envelope was generated. The repetition rate of the mode-locked pulse within the Q-switched envelope of 88 MHz was achieved.

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智能玻璃能够根据人的意愿或者外界环境的变化动态的调节太阳光的输入,是新一代的建筑节能玻璃,目前引起广泛的关注。本文选取了两种典型的智能玻璃——电致变色玻璃和VO2热色玻璃,采用动态能耗分析软件EnergyPlus分别对其建筑节能特性进行了分析,具体研究内容如下: (1)讨论了电致变色玻璃不同控制方式对其节能效果的影响。结果表明,电致变色玻璃选用合适的控制方式可以显著降低建筑的能耗,但如果控制方式选用不当,采用电致变色玻璃后建筑的能耗反而会高于采用普通白玻的能耗。此外,无论在何种控制方式下,采用电致变色/LOW-E的节能效果都要优于电致变色/白玻中空玻璃。 (2)对VO2光学薄膜的膜系结构进行了优化,研究了外观颜色与膜层厚度的关系,设计出的TiO2(135nm)/VO2(50nm)/ITO(45nm)/glass三层膜结构相对于VO2(50nm)/glass的单层膜结构,太阳能调节量提高了从3.7%提高到9.8%,半导体状态时的可见光透过率从33.6%提高到55.5%,金属状态时的可见光透过率从34.0%提高到50.0%,同时半导体与金属状态时的膜面发射率都有很大程度的降低。 (3)研究了VO2热色玻璃的热学性能和建筑节能特性,重点分析了膜层结构、膜面位置、建筑的地理位置等因素对VO2热色玻璃建筑节能效果的影响。结果表明,对于单层VO2热色玻璃,其功能膜面朝向室内比朝向室外可以获得更好的节能效果,而对于由VO2热色玻璃与白玻组成的双层玻璃,其功能膜面位于室内玻璃的外侧时VO2很难起到相应的调节作用。另外,与其他类型的玻璃相比,虽然一定膜层结构下VO2热色玻璃在不同地区的建筑能耗低于白玻,但是在全年以采暖为主的严寒地区和全年以空调为主的夏热冬暖地区,VO2热色玻璃的节能效果分别不及高透型和遮阳型LOW-E玻璃。

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A broadly tunable and high-power grating-coupled external cavity laser with a tuning range of more than 200 nm and a similar to 200-mW maximum output power was realized, by utilizing a gain device with the chirped multiple quantum-dot (QD) active layers and bent waveguide structure. The chirped QD active medium, which consists of QD layers with InGaAs strain-reducing layers different in thickness, is beneficial to the broadening of the material gain spectrum. The bent waveguide structure and facet antireflection coating are both effective for the suppression of inner-cavity lasing under large injection current.