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L'approche Deleuze-Guattari et le fantastique
No full textEn nous appuyant sur l’hypothèse de Gilles Deleuze et Félix Guattari, décrite dans
Mille Plateaux, nous présentons dans notre article la conception de deux modèles, de
deux visions du monde, de la culture et de la littérature : à savoir un modèle traditionnel
de racine et un modèle moderne de rhizome. Nous admettons que le fantastique
traditionnel s’inscrit dans le modèle-racine tandis que le néofantastique est plus proche
du modèle-rhizome. Dans notre article, nous analysons le fantastique-racine dont les
principes s’appuient sur les règles caractérisant le modèle arborescent, c’est-à-dire l’organisation,
la réflexion, l’imitation et l’analogie. Le néofantastique, quant à lui, remplit
les critères qui, selon Deleuze et Guattari, décrivent le rhizome ; ce sont : la connexion,
l’hétérogénéité, la multiplicité, la rupture asignifiante et la cartographie/la décalcomanie.
Le corpus des textes analysés est constitué par « La Vénus d’Ille » comme exemple
du fantastique-racine et les récits du recueil Hôpital Nord d’Andrevon et de Cousin
comme modèle du fantastique-rhizome
Time-delayed effects of a single application of AgNPs on structure of testes and functions in Blaps polychresta Forskal, 1775 (Coleoptera: Tenebrionidae)
Full text linkSilver nanoparticles (AgNPs) are currently themost frequently used engineered nanoparticles. The penetration of
AgNPs into ecosystems is undeniable, and their adverse effects on organismreproduction are of fundamental importance
for ecosystem stability. In this study, the survival time of the Egyptian beetle Blaps polychresta Forskal,
1775 (Coleoptera: Tenebrionidae), after a single application of 7 different doses,was calculated for 30 days. Then,
for the group for which the effect on mortality was calculated as LOAEL - the Lowest Observed Adverse Effect
Level, namely, 0.03 mg AgNPs/g body weight (b.w.t.), the following were assessed: structure and ultrastructure
of gonads by TEM and SEM, cell viability by cytometry, DNA damage by the comet assay, and a variety of stress
markers by spectrophotometric methods. A dose-dependent reduction in the survival time of the insects wa
Revisiting properties of CaCoSinO2n+2. Crystal and electronic structure
Full text linkIn a public space there are several reports of materials with general stoichiometry CaCoSinO2n+2. Pyroxene
CaCoSi2O6 is probably the best-known representative for n = 2 but not much is known about materials with n = 3
and n = 4. In this study, attempts were carried out to synthesize those phantom materials and it was found that
they do not exist as a single phase. A quantitative XRD analysis revealed that their chemical composition is
correct but the formula should be written as CaCoSi2O6 + (n-2)SiO2. Similar qualitative conclusions were drawn
from investigation of magnetic (DC magnetometry) and electronic properties using X-ray Photoelectron Spectroscopy
(XPS) and Si K edge X-ray Absorption Spectroscopy (XAS). Additionally, the DFT ab initio calculations
were carried out to obtain electronic signature from band structure of CaCoSi2O6.
The apparent influence of the excess of SiO2 on magnetic properties of this “series” can be understood in terms
of presence and suppression of secondary phases like Ca2CoSi2O7, which form when the starting materials are not
homogenized properly. Addition of surplus SiO2 suppresses their formation leaving clear signature from CaCoSi2O6,
which also can be synthesized from stoichiometric mixture using proper techniques
Exponential ergodicity in the bounded-Lipschitz distance for some piecewise-deterministic Markov processes with random switching between flows
Full text linkIn this paper, we study a subclass of piecewise-deterministic Markov processes with a Polish state space, involving deterministic motion punctuated by random jumps that occur at exponentially distributed time intervals. Over each of these intervals, the process follows a flow, selected randomly among a finite set of all possible ones. Our main goal is to provide a set of verifiable conditions guaranteeing the exponential ergodicity for such processes (in terms of the bounded Lipschitz distance), which would refer only to properties of the flows and the transition law of the Markov chain given by the post-jump locations. Moreover, we establish a simple criterion on the exponential ergodicity for a particular instance of these processes, applicable to certain biological models, where the jumps result from the action of an iterated function system with place-dependent probabilities
Fused Deposition Modeling as a Possible Approach for the Preparation of Orodispersible Tablets
Full text linkAdditive manufacturing technologies are considered as a potential way to support individualized
pharmacotherapy due to the possibility of the production of small batches of customized
tablets characterized by complex structures. We designed five different shapes and analyzed the effect
of the surface/mass ratio, the influence of excipients, and storage conditions on the disintegration
time of tablets printed using the fused deposition modeling method. As model pharmaceutical
active ingredients (APIs), we used paracetamol and domperidone, characterized by different thermal
properties, classified into the various Biopharmaceutical Classification System groups. We found that
the high surface/mass ratio of the designed tablet shapes together with the addition of mannitol and
controlled humidity storage conditions turned out to be crucial for fast tablet’s disintegration. As a
result, mean disintegration time was reduced from 5 min 46 s to 2 min 22 s, and from 11 min 43 s to
2 min 25 s for paracetamol- and domperidone-loaded tablets, respectively, fulfilling the European
Pharmacopeia requirement for orodispersible tablets (ODTs). The tablet’s immediate release characteristics
were confirmed during the dissolution study: over 80% of APIs were released from printlets
within 15 min. Thus, this study proved the possibility of using fused deposition modeling for the
preparation of ODTs
Indium(II) chloride as a precursor in the synthesis of ternary (Ag–In–S) and quaternary (Ag–In–Zn–S) nanocrystals
Full text linkA new indium precursor, namely, indium(II)
chloride, was tested as a precursor in the synthesis of ternary
Ag−In−S and quaternary Ag−In−Zn−S nanocrystals. This new
precursor, being in fact a dimer of Cl2In−InCl2 chemical structure,
is significantly more reactive than InCl3, typically used in the
preparation of these types of nanocrystals. This was evidenced by
carrying out comparative syntheses under the same reaction
conditions using these two indium precursors in combination with
the same silver (AgNO3) and zinc (zinc stearate) precursors. In
particular, the use of indium(II) chloride in combination with low
concentrations of the zinc precursor yielded spherical-shaped (D =
3.7−6.2 nm) Ag−In−Zn−S nanocrystals, whereas for higher
concentrations of this precursor, rodlike nanoparticles (L = 9−10
nm) were obtained. In all cases, the resulting nanocrystals were enriched in indium (In/Ag = 1.5−10.3). Enhanced indium precursor
conversion and formation of anisotropic, longitudinal nanoparticles were closely related to the presence of thiocarboxylic acid type of
ligands in the reaction mixture. These ligands were generated in situ and subsequently bound to surfacial In(III) cations in the
growing nanocrystals. The use of the new precursor of enhanced reactivity facilitated precise tuning of the photoluminescence color
of the resulting nanocrystals in the spectral range from ca. 730 to 530 nm with photoluminescence quantum yield (PLQY) varying
from 20 to 40%. The fabricated Ag−In−S and Ag−In−Zn−S nanocrystals exhibited the longest, reported to date,
photoluminescence lifetimes of ∼9.4 and ∼1.4 μs, respectively. It was also demonstrated for the first time that ternary (Ag−In−
S) and quaternary (Ag−In−Zn−S) nanocrystals could be applied as efficient photocatalysts, active under visible light (green)
illumination, in the reaction of aldehydes reduction to alcohols
Graviton mass in the era of multi-messenger astronomy
Full text linkThe idea of massive graviton plays a fundamental role in modern physics as a landmark of
most scenarios related to modified gravity theories. Limits on graviton mass can be obtained through
different methods, using all the capabilities of multi-messenger astronomy available today. In this
paper, we consider some emerging opportunities. In particular, modified relativistic dispersion
relations of massive gravitons may lead to changes in the travel time of gravitational waves (GWs)
emitted from distant astrophysical objects. Strong gravitational lensing of signals from a carefully
selected class of extra-galactic sources such as compact object binaries (actually, binary neutron stars)
is predicted to play an important role in this context. Comparing time delays between images of
the lensed GW signal and its electromagnetic (EM) counterpart may be a new model-independent
strategy (proposed by us in X.-L. Fan et al, 2017), which is especially promising in light of the fruitful
observing runs of interferometric GW detectors, resulting in numerous GW signals. In addition to
this direct, kinematic method, one can use an indirect, static method. In this approach, the non-zero
graviton mass would modify estimates of the total cluster mass via a Yukawa term, influencing
the Newtonian potential. In A. Piórkowska-Kurpas et al, 2022, using the X-COP galaxy cluster
sample, we obtained mg < (4.99 6.79) 1029 eV (at 95% C.L.), which is one of the best available
constraints
The Ideological Component in 21st Century Terrorism
Full text linkThe article analyzes transformation of the ideological factor of terrorism in 21st century. The author emphasizes transition from grand narratives (Marxism, fascism) to little narratives of new social movements. In his opinion terrorism without ideology is more dangerous than ideological terrorism
Aggregation of Rankings Using Metaheuristics in Recommendation Systems
Full text linkRecommendation systems are a powerful tool that is an integral part of a great many
websites. Most often, recommendations are presented in the form of a list that is generated by using
various recommendation methods. Typically, however, these methods do not generate identical
recommendations, and their effectiveness varies between users. In order to solve this problem, the
application of aggregation techniques was suggested, the aim of which is to combine several lists
into one, which, in theory, should improve the overall quality of the generated recommendations.
For this reason, we suggest using the Differential Evolution algorithm, the aim of which will be to
aggregate individual lists generated by the recommendation algorithms and to create a single list
that will be fine-tuned to the user’s preferences. Additionally, based on our previous research, we
present suggestions to speed up this process
The effect of cooling rate on the structure and selected properties of AlCoCrFeNiSix (x = 0; 0.25; 0.5; 0.75) high entropy alloys
Full text linkHigh entropy alloys with variable silicon content were prepared by two different methods to determine the influence of the cooling rate and chemical composition on the structure and properties of the alloys. First, the structure of the alloys was investigated using X-ray diffractometry and electron microscopy and compared with Mössbauer spectra to obtain a comprehensive description of the atom arrangement. The formation ability of the BCC and B2 phases was confirmed. The magnetic properties were examined using a vibrating sample magnetometer and Mössbauer spectroscopy. The corrosion resistance behavior was stu
died by electrochemical testing. Our results show that the saturation magnetization tends to decrease with increasing silicon content and that the lowest coercive force was noted for rapidly cooled plates. The highest corrosion resistance in a 3.5% NaCl solution characterizes the AlCoCrFeNiSi0.75 alloy in the form of plates. For which Ecorr and jcorr was equal to − 0.155 V and 0.17 μA/cm2. The addition of Si led to an increase in the hardness of the ingots and plates. For example, AlCoCrFeNiSi0.75 shows 859 HV for the ingot and 727 HV for the plate