1,329 research outputs found
Царський і республіканський Рим в антикознавчих дослідженнях М.П. Драгоманова
У статті розглянуто особливості вивчення та рецепції римської
історії VIII–I ст. до н. е. в антикознавчих студіях М. Драгоманова.
Зроблено висновок, що дослідження М. Драгоманова з історії Риму
вплинули на формування наукових і суспільно-політичних поглядів
вченого, а також Лесі Українки та І. Франка.In the article peculiarities of study and reception of Roman history
VIII–I centuries B.C. in M. Drahomanov’s classical researches are highlighted.
The author concludes that M. Drahomanov’s Roman classical studies
influenced on formation of scientific and political views of
M. Drahomanov, Lesya Ukrainka, I. Franko
Curve counting via stable pairs in the derived category
For a nonsingular projective 3-fold , we define integer invariants
virtually enumerating pairs where is an embedded curve and
is a divisor. A virtual class is constructed on the associated
moduli space by viewing a pair as an object in the derived category of . The
resulting invariants are conjecturally equivalent, after universal
transformations, to both the Gromov-Witten and DT theories of . For
Calabi-Yau 3-folds, the latter equivalence should be viewed as a wall-crossing
formula in the derived category.
Several calculations of the new invariants are carried out. In the Fano case,
the local contributions of nonsingular embedded curves are found. In the local
toric Calabi-Yau case, a completely new form of the topological vertex is
described.
The virtual enumeration of pairs is closely related to the geometry
underlying the BPS state counts of Gopakumar and Vafa. We prove that our
integrality predictions for Gromov-Witten invariants agree with the BPS
integrality. Conversely, the BPS geometry imposes strong conditions on the
enumeration of pairs.Comment: Corrected typos and duality error in Proposition 4.6. 47 page
Surveying activated sludge changes during acclimation with artificial wastewater
Many processes in the chemical and pharmaceutical industries generate wastewater containing organic
toxic compounds and other kinds of xenobiotics. Usually, biological treatments are used to degrade a
great quantity of these substances. However, most of the time, the microorganisms are not adapted and
the treatment can be blocked. Therefore, the first step to make a continuous reactor operative is the
acclimation, i.e., the adaptation of the microorganisms to a specific substrate. During this particular step
of the process there is a selection and a multiplication of specialized microorganisms and physiological
transformations can occur in their metabolic system. Furthermore, combining image processing
techniques have already been successfully used to elucidate the activated sludge morphological changes
for both aggregated and filamentous bacteria contents, during such processes.
The experimental set-up is composed of an aerated reactor and a clarifier. The sludge is recycled from the
clarifier by a peristaltic pump. The complete mixing inside the reactor is guaranteed by the diffusion of
air from its bottom. The reactor was inoculated with biomass collected from a wastewater treatment plant
and fed with an artificial wastewater based on meat extract. During acclimation, chemical parameters
were measured in the influent, reactor and effluent, in order to verify the stability of the process. To
complete the evaluation of the process, microscopy acquisition and image processing and analysis
techniques were performed for aggregates and filamentous bacteria characterization for bright field, Gram
and poly-β-hydroxybutyrate (PHB) staining images. The information extracted from those images
allowed for aggregates and filamentous bacteria contents inspection, identification of PHB storing
microorganisms and, gram-positive and gram-negative filamentous bacteria recognition. Figure 1 presents
activated sludge samples at the beginning and at the end of the acclimation phase. It was found in this
study that biomass changes during the acclimation phase could be effectively monitored, combining
image analysis information and chemical parameters
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