990 resultados para Nichols, Clifton M. (Clifton Melvin), 1830-1903.


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Puroindolines (Pins) and purothionins (Pths) are basic, amphiphilic, cysteine-rich wheat proteins that play a role in plant defense against microbial pathogens. We have examined the co-adsorption and sequential addition of Pins (Pin-a, Pin-b and a mutant form of Pin-b with Trp-44 to Arg-44 substitution) and β-purothionin (β-Pth) model anionic lipid layers, using a combination of surface pressure measurements, external reflection FTIR spectroscopy and neutron reflectometry. Results highlighted differences in the protein binding mechanisms, and in the competitive binding and penetration of lipid layers between respective Pins and β-Pth. Pin-a formed a blanket-like layer of protein below the lipid surface that resulted in the reduction or inhibition of β-Pth penetration of the lipid layer. Wild-type Pin-b participated in co-operative binding with β-Pth, whereas the mutant Pin-b did not bind to the lipid layer in the presence of β-Pth. The results provide further insight into the role of hydrophobic and cationic amino acid residues in antimicrobial activity.

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Changes in the cultures and spaces of death during the Victorian era reveal the shifting conceptualisations and mobilisations of class in this period. Using the example of Brookwood Necropolis, established 1852 in response to the contemporary burial reform debate, the paper explores tensions within the sanitary reform movement, 1853–1903. Whilst reformist ideology grounded the cemetery's practices in a discourse of inclusion, one of the consequences of reform was to reinforce class distinctions. Combined with commercial imperatives and the modern impulse towards separation of living and dead, this aspect of reform enacted a counter-discourse of alienation. The presence of these conflicting strands in the spaces and practices of the Necropolis and their changes during the time period reflect wider urban trends.

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The calcium-mediated interaction of DNA with monolayers of the non-toxic, zwitterionic phospholipid, 1,2-distearoyl-sn-glycero-3-phosphocholine when mixed with 50 mol% of a second lipid, either the zwitteronic 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine or neutral cholesterol was investigated using a combination of surface pressure-area isotherms, Brewster angle microscopy, external reflectance Fourier transform infrared spectroscopy and specular neutron reflectivity in combination with contrast variation. When calcium and DNA were both present in the aqueous subphase, changes were observed in the compression isotherms as well as the surface morphologies of the mixed lipid monolayers. In the presence of calcium and DNA, specular neutron reflectivity showed that directly underneath the head groups of the lipids comprising the monolayers, DNA occupied a layer comprising approximately 13 and 18% v/v DNA for the 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine and cholesterol-containing monolayers, respectively. The volume of the corresponding layer for 1,2-distearoyl-sn-glycero-3-phosphocholine only containing monolayers was ∼15% v/v DNA. Furthermore regardless of the presence and nature of the second lipid and the surface pressure of the monolayer, the specular neutron reflectivity experiments showed that the DNA-containing layer was 20–27 Å thick, suggesting the presence of a well-hydrated layer of double-stranded DNA. External reflectance Fourier transform infrared studies confirmed the presence of double stranded DNA, and indicated that the strands are in the B-form conformation. The results shed light on the interaction between lipids and nucleic acid cargo as well as the role of a second lipid in lipid-based carriers for drug delivery.

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The interaction between tryptophan-rich puroindoline proteins and model bacterial membranes at the air-liquid interface has been investigated by FTIR spectroscopy, surface pressure measurements and Brewster angle microscopy. The role of different lipid constituents on the interactions between lipid membrane and protein was studied using wild type (Pin-b) and mutant (Trp44 to Arg44 mutant, Pin-bs) puroindoline proteins. The results show differences in the lipid selectivity of the two proteins in terms of preferential binding to specific lipid head groups in mixed lipid systems. Pin-b wild type was able to penetrate mixed layers of phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) head groups more deeply compared to the mutant Pin-bs. Increasing saturation of the lipid tails increased penetration and adsorption of Pin-b wild type, but again the response of the mutant form differed. The results provide insight as to the role of membrane architecture, lipid composition and fluidity, on antimicrobial activity of proteins. Data show distinct differences in the lipid binding behavior of Pin-b as a result of a single residue mutation, highlighting the importance of hydrophobic and charged amino acids in antimicrobial protein and peptide activity.

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We see today many efforts to quantify biodiversity in different biomes. It is very important then to develop and to apply other methodologies that allow us to assess biodiversity. Here we present an example of application of three tools with this goal. We analyzed two populations of Plebeia remota from two distinct biomes that already showed several differences in morphology and behavior. Based on these differences, it has been suggested that the populations of Cunha and Prudentopolis do not represent a single species. In order to verify the existence or absence of gene flow between these two groups, we characterized the patterns of mtDNA through RFLP, the patterns of wing venation through geometric morphometry, and the cuticular hydrocarbons through gas chromatography-mass spectrometry. We used bees collected in these two locations and also from colonies which have being kept for around 9 years at Sao Paulo University. We found six different haplotypes in these specimens, of which three of them occurred exclusively in the population of Cunha and three only in the Prudentopolis population. The fact that the populations do not share haplotypes suggests no maternal gene flow between them. The two populations were differentiated by the pattern of the wing veins. They also had different mixtures of cuticle hydrocarbons. Furthermore it was shown that the colonies kept at the university did not hybridize. These two groups may constitute different species. We also show here the importance of using other methodologies than traditional taxonomy to assess and understand biodiversity, especially in bees.

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Chaetopelma Ausserer 1871 and Nesiergus Simon 1903 are revised. Cratorrhagus Simon 1891 is considered a junior synonym of Chaetopelma. Cratorrhagus tetramerus (Simon 1873) and the female of Cratorrhagus concolor (Simon 1873) are conspecific with C. olivaceum (C. L. Koch 1841). Ischnocolus gracilis Ausserer 1871, Ischnocolus syriacus Ausserer 1871, Chaetopelma shabati Hassan 1950 and Ischnocolus jerusalemensis Smith 1990 are also treated here as junior synonyms of C. olivaceum. Chaetopelma adenense Simon 1890 is proposed as a junior synonym of Ischnocolus jickelii L. Koch 1875. Chaetopelma gardineri Hirst 1911 is transferred to Nesiergus. Hence, Chaetopelma comprises three valid species: C. olivaceum (C. L. Koch 1841); C. karlamani Vollmer 1997; C. concolor (Simon 1873) n. comb. from the Middle East and northeastern Africa. Nesiergus, which appears endemic to the Seychelles archipelago, now comprises three valid species: N. gardineri (Hirst 1911) n. comb.; N. halophilus Benoit 1978; N. insulanus Simon 1903.

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Uppsatsens syfte är att undersöka den mediala debatten i början av 1900-talet gällande sekula-riseringen, i detta fall folkskolans skiljande frÃ¥n kyrkan, utifrÃ¥n tvÃ¥ folkskollärartidningar. Källmaterialet utgörs av Sveriges all¤nna folkskollärareförenings tidning Svensk läraretid-ning, samt Svenska folkskolans vänners tidning Folkskolans vän. Det tidningsmaterial som studerats är Ã¥rgÃ¥ng 1903 och 1909. För att besvara syftet har sekulariseringsbegreppet delats in i tvÃ¥ avdelningar, dels med fokus pÃ¥ debatten om folkskolans administrativa skiljande frÃ¥n kyrkan, samt dels synen pÃ¥ kristendomsundervisningens innehÃ¥ll och utformning. Resultatet visar att bÃ¥da folkskollärartidningarna hävdade att lärarkÃ¥ren borde fÃ¥ mer administrativt in-flytande över folkskolan, även om Svensk läraretidning är nÃ¥got mer aggressiv i sin kritik mot svenska kyrkans administrativa folkskoleauktoritet. Tidningarnas syn pÃ¥ kristendomsämnet skiljer sig, dÃ¥ Folkskolans vän önskar att behÃ¥lla den konfessionella undervisningen med fokus pÃ¥ katekesen, till skillnad frÃ¥n Svensk läraretidning som kräver en mer all¤n kristen-domsundervisning. Detta fÃ¥r även betydelse för tidningarnas syn pÃ¥ vad som var folkskolans huvudsakliga uppgift.

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Syftet med denna uppsats har varit att studera hur barnavÃ¥rdsnämnden i Stora Tuna verkställde lagstiftningen om uppfostran Ã¥t vanartade och i sedligt avseende försummade barn. För att uppnÃ¥ syftet med studien har barnavÃ¥rdsnämndens leda¶ter undersökts, lika sÃ¥ de an¤lda barnen. Vad an¤ldes de för, vilka blev konsekvenserna och vilka var det som stod för an¤lningarna? Resultaten jämförs med tidigare forskning frÃ¥n andra platser. Huvudsakligen har protokoll frÃ¥n barnavÃ¥rdsnämndens sammanträden mellan 1903 och 1917 använts för att besvara frÃ¥geställningarna.Resultatet visar att en klar majoritet av nämndens leda¶ter representerade medelklassen eller överklassen, endast ett fÃ¥tal kom frÃ¥n arbetarklassen. Men de barn som an¤ldes kom nästan uteslutande frÃ¥n arbetarklassen. Detta är nÃ¥got som den tidigare forskningen ocksÃ¥ framhÃ¥ller. Pojkar an¤ldes i betydligt högre utsträckning än flickor, men de flickor som an¤ldes dömdes betydligt hÃ¥rdare än pojkarna. Flickorna an¤ldes främst pÃ¥ grund av de bristande hemförhÃ¥llanden och pÃ¥följderna blev oftast att de skiljdes frÃ¥n hemmet till fosterhem eller till barnhem. Pojkarna an¤ldes främst för stöld och den vanligaste pÃ¥följden blev en allvarlig varning. Polisen var den grupp som an¤lde flest barn till nämnden.

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A critical question in data mining is that can we always trust what discovered by a data mining system unconditionally? The answer is obviously not. If not, when can we trust the discovery then? What are the factors that affect the reliability of the discovery? How do they affect the reliability of the discovery? These are some interesting questions to be investigated.

In this paper we will firstly provide a definition and the measurements of reliability, and analyse the factors that affect the reliability. We then examine the impact of model complexity, weak links, varying sample sizes and the ability of different learners to the reliability of graphical model discovery. The experimental results reveal that (1) the larger sample size for the discovery, the higher reliability we will get; (2) the stronger a graph link is, the easier the discovery will be and thus the higher the reliability it can achieve; (3) the complexity of a graph also plays an important role in the discovery. The higher the complexity of a graph is, the more difficult to induce the graph and the lower reliability it would be.

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In text categorization applications, class imbalance, which refers to an uneven data distribution where one class is represented by far more less instances than the others, is a commonly encountered problem. In such a situation, conventional classifiers tend to have a strong performance bias, which results in high accuracy rate on the majority class but very low rate on the minorities. An extreme strategy for unbalanced, learning is to discard the majority instances and apply one-class classification to the minority class. However, this could easily cause another type of bias, which increases the accuracy rate on minorities by sacrificing the majorities. This paper aims to investigate approaches that reduce these two types of performance bias and improve the reliability of discovered classification rules. Experimental results show that the inexact field learning method and parameter optimized one-class classifiers achieve more balanced performance than the standard approaches.

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Land use change has occurred rapidly in southwestern Victoria over the last decade and is expected to continue, albeit at a slower pace. One of these changes has been the development of 'new forests', that is industrial and farm forestry plantations and environmental plantings. Some of the challenges that these land use changes pose for water and natural resource managers are discussed. Land use change is expected to substantially reduce potential water yield in four of the region's seven drainage basins (A).

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This paper is on adaptive real-time searching of credit application data streams for identity crime with many search parameters. Specifically, we concentrated on handling our domain-specific adversarial activity problem with the adaptive Communal Analysis Suspicion Scoring (CASS) algorithm. CASS's main novel theoretical contribution is in the formulation of State-of- Alert (SoA) which sets the condition of reduced, same, or heightened watchfulness; and Parameter-of-Change (PoC) which improves detection ability with pre-defined parameter values for each SoA. With pre-configured SoA policy and PoC strategy, CASS determines when, what, and how much to adapt its search parameters to ongoing adversarial activity. The above approach is validated with three sets of experiments, where each experiment is conducted on several million real credit applications and measured with three appropriate performance metrics. Significant improvements are achieved over previous work, with the discovery of some practical insights of adaptivity into our domain.


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Automated adversarial detection systems can fail when under attack by adversaries. As part of a resilient data stream mining system to reduce the possibility of such failure, adaptive spike detection is attribute ranking and selection without class-labels. The first part of adaptive spike detection requires weighing all attributes for spiky-ness to rank them. The second part involves filtering some attributes with extreme weights to choose the best ones for computing each example’s suspicion score. Within an identity crime detection domain, adaptive spike detection is validated on a few million real credit applications with adversarial activity. The results are F-measure curves on eleven experiments and relative weights discussion on the best experiment. The results reinforce adaptive spike detection’s effectiveness for class-label-free attribute ranking and selection.