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1.
Ethanol production from lignocellulosic materials is often conceived considering independent, stand-alone production plants; in the Brazilian scenario, where part of the potential feedstock (sugarcane bagasse) for second generation ethanol production is already available at conventional first generation production plants, an integrated first and second generation production process seems to be the most obvious option. In this study stand-alone second generation ethanol production from surplus sugarcane bagasse and trash is compared with conventional first generation ethanol production from sugarcane and with integrated first and second generation; simulations were developed to represent the different technological scenarios, which provided data for economic and environmental analysis. Results show that the integrated first and second generation ethanol production process from sugarcane leads to better economic results when compared with the stand-alone plant, especially when advanced hydrolysis technologies and pentoses fermentation are included.  相似文献   

2.
Summary Segregation of mitochondrial genomes in yeast zygotes has been investigated by partial pedigree analysis of crosses involving the markers cap, ery, oli1 and par. The results demonstrate that the segregation pattern of markers is non-random during the first zygote generation and is directly related to slow mixing of the zygote cytoplasm. We have observed that a first bud may be formed at the center or either end of the dumbbell-shaped zygote. Cytoplasmic mixing is particularly slow in those zygotes producing first end buds.Clones derived from first end buds are usually pure (or nearly so) for a parental genotype and so detectable recombination of mitochondrial markers is reduced in these zygotes. Cells derived from a zygote after removal of a first end bud are predominantly of the other parental genotype. This observation suggests that a large fraction of the available segregating units enters each first bud and illustrates one means of obtaining complete segregation (even in multi-factor crosses) at the first generation. First center buds generally receive mitochondrial markers from both parents and the recombination frequency in such clones (and the clones derived from isolated first center buds) is significantly higher than in similar clones from zygotes with first end buds. Therefore, the distribution of first bud positions within a population of zygotes can influence the recombination frequency between mitochondrial loci. The delay in cytoplasmic mixing in combination with certain patterns of zygotic budding can distort the relationship between input of mitochondrial genomes and the output of a cross.The phage analogy model of yeast mitochondrial genetics has been re-examined in light of these data. The assumption of rapid panmixis is not supported by the data from any of the crosses analyzed here. Since panmixis is most closely approximated in zygotes with first center buds, crosses with predominantly zygotes of that type may be the ones where the model is most applicable.  相似文献   

3.
Two cases of cutaneous adiaspiromycosis by Emmonsia crescens are reported. This is the first human skin infection by this species and is the first report of its kind in man from India. In the first patient, the agent was demonstrated in KOH mounts, histology and culture from irregular, pigmented skin plaques on the right gluteal area. The lesion also contained calcium. In the second patient the fungus was demonstrated histologically in a knee lesion. The agent had elicited a histiocytic and giant cell reaction in the dermis in both cases. The first patient suffered from anaemia and epilepsy and the second suffered from nephropathy with chyluria. The skin lesions were surgically excised with skin grafting in the first patient.  相似文献   

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F S Allen  G W Daub 《Biopolymers》1974,13(2):241-255
Procedures are developed which make a first neighbor frequency analysis possible from a CD spectrum of homopyrimidine: homopurine DNA's. The contribution to the CD spectrum from the various first neighbor frequencies present in homopyrimidine: homopurine-type DNA's has been determined, and hence the CD spectrum for any DNA of this type with known first neighbor frequencies can easily be calculated. An identical analysis is presented for the determination of extinction coefficients. It is further shown that unlike the more usual heteropurine–pyrimidine DNA's a random sequence does not lead to a simplified formalism. Finally, it is concluded that the homopyrimidine: homopurine DNA's have a structure that is different from that of the more usual heterobase DNA's. A procedure capable of determining first neighbor frequencies from a CD spectrum for heterobase and/or homopurine: homopyrimidine DNA's is described. This procedure is used to determine that there is only minimal interference between these two types of DNA in the first neighbor analysis.  相似文献   

7.
The first shotgun genome sequence of a microbial pathogen from the Philippines is reported. Yersinia enterocolitica subsp. palearctica strain PhRBD_Ye1 is the first Y. enterocolitica strain sequenced from an animal source, swine, which is a natural source of yersiniosis. The closest phylogenetic match is a human clinical isolate from Germany.  相似文献   

8.
DNA sourced from faeces is notoriously less reliable than that from tissue. Hence, understanding whether faecal pellet quality varies within faecal piles may be important for sample selection. We hypothesized that the order in which faecal pellets are deposited may influence microsatellite polymerase chain reaction (PCR) amplification success from sampled faeces, more specifically, that first pellets deposited will have signatures of greater success than later ones. In a first test of the hypothesis, first and later-deposited pellets, as determined from the direction of footprints, were collected from fresh (overnight) faecal piles of northern hairy-nosed wombats (Lasiorhinus krefftii). DNA extracts were typed for seven microsatellite loci. We found that faecal deposition order significantly affected optical density of bands on autoradiographs (a measure of PCR amplification success) when the first faecal pellet was compared with the last one, but not when the first pellet was only distinguishable from later ones. The absence of a difference in amplification rate between first and later pellets is likely a reflection of the overall high amplification success in this study. That first pellets deposited yield more product suggests they contain more intestinal cells. Although further comparisons are needed, these results may inform sample selection in species for which success of microsatellite PCR amplification of faecal DNA is low. Deposition order may have more of an impact on amplification success and genotyping errors as faecal age increases.  相似文献   

9.
We report a dead, 229-cm-long Pacific sleeper shark, Somniosus pacificus, discovered in 1998 along the shore at Point Hope, Alaska. This is the first definitive record of this species from within the Arctic Circle, the first definitive report of a shark from the Chukchi Sea, and the first report of a shark other than a Greenland shark from within the Arctic Circle.A. Kowunna Sr. is deceased  相似文献   

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记述印度颊脊隐翅虫属Induquedius中国1新种,刘氏印度颊脊隐翅虫Induquedius liuae sp. nov.和中国1新纪录种,捷印度颊脊隐翅虫Ⅰ.baliyo Smetana,1988及中国大陆1新纪录种,台湾印度颊脊隐翅虫Ⅰ.formosae(Cameron),1949.新种与来自锡金的Ⅰ.sikkimensis(Cameron),1932很相似,但雄性外生殖器中叶端部更窄缩,侧叶侧支端部各有4根细毛,腹部第8腹板端凹缘很浅,与后者不同.  相似文献   

12.
记述了中国蝶角蛉科1新纪录属原锯角蝶角蛉属Protacheron Weele,1908,描述了1新纪录种Protacheronphilippinensis和1新种Protacheron guangxiensis sp.nov..标本保存在中国农业大学昆虫博物馆.  相似文献   

13.
First is best     
Carney DR  Banaji MR 《PloS one》2012,7(6):e35088
We experience the world serially rather than simultaneously. A century of research on human and nonhuman animals has suggested that the first experience in a series of two or more is cognitively privileged. We report three experiments designed to test the effect of first position on implicit preference and choice using targets that range from individual humans and social groups to consumer goods. Experiment 1 demonstrated an implicit preference to buy goods from the first salesperson encountered and to join teams encountered first, even when the difference in encounter is mere seconds. In Experiment 2 the first of two consumer items presented in quick succession was more likely to be chosen. In Experiment 3 an alternative hypothesis that first position merely accentuates the valence of options was ruled out by demonstrating that first position enhances preference for the first even when it is evaluatively negative in meaning (a criminal). Together, these experiments demonstrate a "first is best" effect and we offer possible interpretations based on evolutionary mechanisms of this "bound" on rational behavior and suggest that automaticity of judgment may be a helpful principle in clarifying previous inconsistencies in the empirical record on the effects of order on preference and choice.  相似文献   

14.
Abstract  Fusacarus australis sp. n. (Acari: Glycyphagidae) is described from specimens from tree holes and rainforest litter in Lamington National Park, Queensland. This is the first record of Fusacarus Michael from the Southern Hemisphere, and the first Australian native species of Glycyphagidae. A key to the world fauna of Fusacarus is provided.  相似文献   

15.
We consider a continuous stochastic process defined as a drifted Ornstein-Uhlenbeck, for which the first passage time is of interest. The process being non-homogeneous, the first passage time probability density function cannot be found analytically, but numerical methods enable to find its estimate. Estimating the first passage time implies solving an unsteady convection-diffusion equation, with variable coefficients, and we use an implicit Euler scheme to solve it. This work is applied to simulated data, and the continuous process is inspired from recent work on biological marker modelling for HIV-positive patients. The first passage time probability density function can be useful to compare the marker progression in different groups. Numerical results show that the first passage time is highly dependent from the process perturbation, and is then more relevant than methods not considering the stochastic process directly to compare the progression.  相似文献   

16.
The first known indicator of probable fern epiphytism in the Tertiary fossil record is documented from the Eocene London Clay of southeast England. This pyritised fern rachis exhibits major deviation from the basic form of petiolar vascular trace morphology shown by the other London Clay fossil ferns and is here attributed to the Polypodiaceae. This represents the first known occurrence of this family in the London Clay macroflora, and brings the total of distinct fern rachis types from the Lower Tertiary of southeast England to six. The significance of this find is interpreted in relation to its probable origins from a tropical rainforest palaeoflora in which it is proposed that this specimen represents the first occurrence of an epiphytic component.  相似文献   

17.
The purpose of the present study was to examine whether excessive CO2 output (VCO2excess) is dominantly attributable to hyperventilation during the period of recovery from repeated cycling sprints. A series of four 10-sec cycling sprints with 30-sec passive recovery periods was performed two times. The first series and second series of cycle sprints (SCS) were followed by 360-sec passive recovery periods (first recovery and second recovery). Increases in blood lactate (DeltaLa) were 11.17+/-2.57 mM from rest to 5.5 min during first recovery and 2.07+/-1.23 mM from the start of the second SCS to 5.5 min during second recovery. CO2 output (VCO2) was significantly higher than O2 uptake (VO2) during both recovery periods. This difference was defined as VCO2excess. VCO2excess was significantly higher during first recovery than during second recovery. VCO2excess was added from rest to the end of first recovery and from the start of the second SCS to the end of second recovery (CO2excess). DeltaLa was significantly related to CO2excess (r=0.845). However, ventilation during first recovery was the same as that during second recovery. End-tidal CO2 pressure (PETCO2) significantly decreased from the resting level during the recovery periods, indicating hyperventilation. PETCO2 during first recovery was significantly higher than that during second recovery. It is concluded that VCO2excess is not simply determined by ventilation during recovery from repeated cycle sprints.  相似文献   

18.
The first Carboniferous conodonts studied from the Cares river section correspond to fifteen species and one subspecies from seven genera, some of them reported from the Picos de Europa Unit for the first time. The conodonts belong to several zones between the upper Tournaisian and the upper Serpukhovian-lower Bashkirian. Furthermore, the species Idiognathodus incurvus Dunn is reported for the first time in the Cantabrian Mountains and southern Europe, from upper Bashkirian or lower Moscovian beds.  相似文献   

19.
In most insect species where double matings occur, sperm from the second male preferentially fertilize subsequent eggs. However, we demonstrate here that, as already shown for some other hymenopteran species, this is not the case in the ichneumonid waspDiadromus pulchellus (Wesmeal): sperm from the first male usually father all the female progeny. This precedence of the first male sperm is also observed in double matings involving an haploid male and a diploid sterile male, whichever is the first mating male. We discuss the consequences of this phenomenon from an evolutionary point of view.  相似文献   

20.
Dicyemennea canadensis n. sp. is described from a bathyal octopus collected off Canada in the Bay of Fundy. The dicyemid is a small species that rarely exceeds 600 microm in length. The vermiform stages are further characterized as having 17-23 peripheral cells, a conical-shaped calotte, an axial cell that extends to the base of the propoplar cells, and no abortive axial cells. Infusoriform embryos consist of 37 cells. There is 1 nucleus in each urn cell, and refringent bodies are absent. This is the first dicyemid to be described from the cephalopod Bathypolypus arcticus (Prosch. 1847), and the first dicyemid reported from Canada. In addition, it is the first species of Dicyemennea from the northwestern Atlantic Ocean to be described.  相似文献   

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