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1.
2.
The discrimination problem for two normal populations with the same covariance matrix when additional information on the population is available is considered. A study of the robustness properties against training sample contamination of classification rules that incorporate this additional information is performed. These rules have received recently attention where their total misclassification probability (TMP) is proved to be lower than Fisher's linear discriminant rule. The results of a simulation study on the TMP which compares the behaviour of the new rules against Fisher's rule and some of its robustified versions under different types of contamination are presented. These results show that the rules that incorporate the additional information not only have lower TMP, but they also prevent against some types of contamination. In order to achieve prevention from all types of contamination a robustifed version of these rules is recommended. 相似文献
3.
Nonisothermal thermogravimetry differential scanning calorimetry (TG‐DSC) mounting is intensively used for the determination of kinetic parameters and reaction heat along the chemical transformation of a solid. Nevertheless, when tests are performed with heating rates as high as those encountered in industrial processes, e.g., several tens of K min–1, there is great uncertainty in the knowledge of the exact sample temperature. In this work, a method to derive a simple mathematical expression is proposed and fully described in order to calculate the real sample temperature throughout a temperature‐ramped test on a commercial apparatus. The furnace temperature and the heat flow signals were used, together with the crucible specific heat and the heating rate. A number of validation tests were performed to derive similar reaction rates for a reference. First‐order kinetic reactions were presented and reconciled over a large range of heating rates from 3 to 50 K min–1. 相似文献
4.
In a study of the enlargement of pores of coals it has been found that treatment of a bituminous coal (PSOC No. 371, from the Pennsylvania State University Coal Section) with a 5:95 O2:N2 stream 4 h at 400 °C increases the surface area as measured by nitrogen adsorption at 77K by a factor of at least 50 to a value 52 m2 g?1. The increase in pore size was accompanied by a 9.7% weight loss. Simultaneously, the area as measured by carbon dioxide at 195K increased from 61 to 136 m2 g?1 and that measured by carbon dioxide at room temperature increased from 125 to 237 m2 g?1. Attempts to enlarge the pores by oxidation with hydrogen peroxide or ozone were unsuccessful. A Pittsburgh coal subject to a small percentage of oxygen in nitrogen or steam at 300 to 400 °C showed a surface area as measured by nitrogen adsorption of less than 1 m2 g?1 both before and after such pretreatment. This same coal with a 5:95 O2:N2 stream for 4 h at 450 °C showed a surface area of 110 m2 g?1 measured by nitrogen adsorption at 77K. 相似文献
5.
R. Baixauli A. Salvador S. M. Fiszman C. Calvo 《Journal of the American Oil Chemists' Society》2002,79(11):1127-1131
Oil degradation caused by the number of fryings performed and the effect of oil degradation on the color of fried battered
squid rings were studied. Spectrophotometric techniques with absorbance in the UV and visible ranges, and iodine, peroxide,
and acid values were used to determine oil degradation. Determination of various CIELAB parameters in order to study the external
color of the fried battered squid rings revealed no differences in color due to the number of fryings. A study of the color
of the battered squid rings at various frying times and temperatures showed significant differences for both variables. Although
there was some degradation in the oil after 20 fryings, appearing as a slight darkening, it did not affect the final color
of the fried, battered squid rings. 相似文献
6.
We try to reproduce experimental mobility curves in ultrathin silicon-on-insulator inversion layers using a Monte Carlo simulator
and a bulk model for the electron scattering with acoustic phonons. While it is possible to reproduce the experimental behavior
for the thicker samples, the electron mobility is strongly overestimated when the thinnest samples are considered. The mobility
curves for the thinnest samples can be reproduced using the same model if the deformation potential parameter increases as
the silicon thickness decreases. This fact shows that acoustic phonons are also confined in ultrathin silicon on insulator
layers. We then study confined phonons in single and three layer structures in order to give a physical motivation to the
increase of acoustic phonon scattering rate for in ultrathin silicon layers. 相似文献
7.
Alejandro Flores-Len Clara Perz Moro Raul Martí Joaquin Beltran Salvador Rosell Jaime Cebolla-Cornejo Belen Pic 《International journal of molecular sciences》2022,23(13)
Spain is a secondary centre of the diversification of the melon (Cucumis melo L.), with high diversity represented in highly appreciated landraces belonging to the Flexuosus and Ibericus groups. A collection of 47 accessions of Flexuosus, Chate, Piel de Sapo, Tendral, Amarillo, Blanco, and Rochet was analysed using a genotyping-by-sequencing (GBS) approach. A total of 66,971 quality SNPs were identified. Genetic analysis differentiated Ibericus accessions and exotic materials (Ameri, Momordica, Kachri, and Agrestis), while Flexuous accessions shared ancestry between them. Within the Ibericus group, no clear genomic distinction could be identified for the different landraces evaluated, with accessions of different landraces showing high genetic similarity. The morphological characterization confirmed that the external colour and fruit shape had been used as recognition patterns for Spanish melon landraces, but variability within a landrace exists. Differences were found in the sugars and acid and volatile profiles of the materials. Flexuosus and Chate melons at the immature commercial stage accumulated malic acid and low levels of hexoses, while Ibericus melons accumulated high contents of sucrose and citric acid. Specific trends could be identified in the Ibericus landraces. Tendral accumulated low levels of sugars and citric acid and high of malic acid, maintaining higher firmness, Rochet reached higher levels of sugars, and Amarillo tended to lower malic acid contents. Interestingly, high variability was found within landraces for the acidic profile, offering possibilities to alter taste tinges. The main volatile organic compounds (VOCs) in Flexuosus and Chate were aldehydes and alcohols, with clear differences between both groups. In the Ibericus landraces, general trends for VOC accumulation could be identified, but, again, a high level of variation exists. This situation highlights the necessity to develop depuration programs to promote on-farm in situ conservation and, at the same time, offers opportunities to establish new breeding program targets and to take advantage of these sources of variation. 相似文献
8.
Sandra Brasil Mariateresa Allocca Salvador C. M. Magrinho Inês Santos Madalena Raposo Rita Francisco Carlota Pascoal Tiago Martins Paula A. Videira Florbela Pereira Giuseppina Andreotti Jaak Jaeken Kristin A. Kantautas Ethan O. Perlstein Vanessa dos Reis Ferreira 《International journal of molecular sciences》2022,23(15)
Advances in research have boosted therapy development for congenital disorders of glycosylation (CDG), a group of rare genetic disorders affecting protein and lipid glycosylation and glycosylphosphatidylinositol anchor biosynthesis. The (re)use of known drugs for novel medical purposes, known as drug repositioning, is growing for both common and rare disorders. The latest innovation concerns the rational search for repositioned molecules which also benefits from artificial intelligence (AI). Compared to traditional methods, drug repositioning accelerates the overall drug discovery process while saving costs. This is particularly valuable for rare diseases. AI tools have proven their worth in diagnosis, in disease classification and characterization, and ultimately in therapy discovery in rare diseases. The availability of biomarkers and reliable disease models is critical for research and development of new drugs, especially for rare and heterogeneous diseases such as CDG. This work reviews the literature related to repositioned drugs for CDG, discovered by serendipity or through a systemic approach. Recent advances in biomarkers and disease models are also outlined as well as stakeholders’ views on AI for therapy discovery in CDG. 相似文献
9.
In recent years, several extensions of tree automata have been considered. Most of them are related with the capability of testing equality or disequality of certain subterms of the term evaluated by the automaton. In particular, tree automata with global constraints are able to test equality and disequality of subterms depending on the state to which they are evaluated. The emptiness problem is known decidable for this kind of automata, but with a non-elementary time complexity, and the finiteness problem remains unknown. In this paper, we consider the particular case of tree automata with global constraints when the constraint is a conjunction of disequalities between states, and the disequality predicate is forced to be reflexive. This restriction is significant in the context of XML definitions with monadic key constraints. We prove that emptiness and finiteness are decidable in triple exponential time for this kind of automata. 相似文献
10.
Salvador Barber M. José Torner M. Antonia Martínez-Anaya Carmen Benedito de Barber 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1989,189(1):6-11
Summary Changes in mono- and disaccharides and acetic and lactic acid production of six different straight doughs elaborated with combinations of pure strains of yeastsSaccharomyces cerevisiae andCandida boidinii and lactic acid bacteriaLactobacillus plantarum andStreptococcus sp have been investigated, as well as the baking quality of the resulting breads. The type and proportion of the fermentative microorganisms were found to influence the biochemical activity of the doughs. The sugar levels after mixing reached different proportions, depending on the type of sugar and the type of microorganisms used. After proofing, the glucose and fructose content of the doughs decreased to 0.01%–0.02% db and maltose decreased to 0.45%–0.11 % db. Acetic and lactic acids underwent variable changes during fermentation, depending on the type of dough. Lactic acid showed higher levels than acetic acid. Bread made from these doughs had different sensory characteristics, texture, edibility and overall acceptance, as well as different lactic and acetic acid contents, depending on the mixture of microorganisms inoculated.
Presented at the 8th International Cereal and Bread Congress, Lausanne, Switzerland, June 1988.
This paper is a part of a doctoral thesis 相似文献
Biochemische Merkmale und Leistungsfahigkeit der mit Mischungen reiner Mikroorganismen hergestellten Weizenbackteige
Zusammenfassung Die Forschungsaufgabe befaßte sich mit den Veranderungen der Mono- und Disaccharide, mit der Entstehung von Essig- und Milchsaure in sechs Teigen, die mit Kombinationen reiner HefekulturenSaccharomyces cerevisiae undCandida boidinii und MilchsäurebakterienLactobacillus plantarum undStreptococcus sp hergestellt waren und mit den sich daraus ergebenden Qualitätsmerkmalen der Brote. Die Art und Anteile der Mikroorganismen übten einen entscheidenden Einfluß auf die biochemische Aktivität der Teige aus. Nach dem Knetvorgang konnten unterschiedliche Gehalte gemäß der eingesetzten Saccharide und Mikroorganismen festgestellt werden. Der Glucose- und Fructoseanteil der fermentierten Teige verringerte sich auf 0,01–0,02% t. g., der Maltoseanteil auf 0,45-0,11% t.g. In den einzelnen Teigen veranderten sich wahrend der Garung die Essig-und Milchsauregehalte unterschiedlich. Bei der Milchsaure konnte eine grbBere Zunahme und somit höhere Endgehalte als bei der Essigsaure festgestellt werden. Die mit diesen Teigen hergestellten Brote erreichten verschiedene Textureigenschaften (Weichheit der Krume) und sensorische Merkmale, insbesondere Kaufahigkeit und Geschmack Bowie einen, entsprechend der Mikroorganismenmischung, höheren oder geringeren Milch- und Essigsäuregehalt.
Presented at the 8th International Cereal and Bread Congress, Lausanne, Switzerland, June 1988.
This paper is a part of a doctoral thesis 相似文献