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2022 ◽  
Vol 12 ◽  
Author(s):  
Ryuichi Nakano ◽  
Yuki Yamada ◽  
Akiyo Nakano ◽  
Yuki Suzuki ◽  
Kai Saito ◽  
...  

Various carbapenemases have been identified in the Enterobacteriaceae. However, the induction and corresponding regulator genes of carbapenemase NmcA has rarely been detected in the Enterobacter cloacae complex (ECC). The NmcA-positive isolate ECC NR1491 was first detected in Japan in 2013. It was characterized and its induction system elucidated by evaluating its associated regulator genes nmcR, ampD, and ampR. The isolate was highly resistant to all β-lactams except for third generation cephalosporins (3GC). Whole-genome analysis revealed that blaNmcA was located on a novel 29-kb putatively mobile element called EludIMEX-1 inserted into the chromosome. The inducibility of β-lactamase activity by various agents was evaluated. Cefoxitin was confirmed as a strong concentration-independent β-lactamase inducer. In contrast, carbapenems induced β-lactamase in a concentration-dependent manner. All selected 3GC-mutants harboring substitutions on ampD (as ampR and nmcR were unchanged) were highly resistant to 3GC. The ampD mutant strain NR3901 presented with a 700 × increase in β-lactamase activity with or without induction. Similar upregulation was also observed for ampC and nmcA. NR1491 (pKU412) was obtained by transforming the ampR mutant (135Asn) clone plasmid whose expression increased by ∼100×. Like NR3901, it was highly resistant to 3GC. Overexpression of ampC, rather than nmcA, may have accounted for the higher MIC in NR1491. The ampR mutant repressed nmcA despite induction and it remains unclear how it stimulates nmcA transcription via induction. Future experiments should analyze the roles of nmcR mutant strains.


Author(s):  
Roman Matykowski ◽  
Anna Tobolska

Based on World Steel Association statistical data, this study brings together changes in the geographical pattern of global steel production in the first two decades of the 21st century and its fluctuations during economic and social crises. The analysis indicates a strong concentration of production in several countries, and among them, China has become the leader in the last two decades. Since 2017, it has produced more than half of all steel globally, and in 2019 its annual production exceeded one billion tonnes. In 2020 the largest Chinese concern, China Baowu Group, ousted ArcelorMittal from its leading position in the ranking of the world’s largest steel concerns. Such an intense concentration of steel production in one country and the strategies of internal consolidation of Chinese steel producers are a clear signal that China is taking control of the global market for this raw material, essential for many economic sectors.


2021 ◽  
pp. 147737082110601
Author(s):  
Máximo Sozzo

In this paper, I will describe how two strong connections between, on the one hand, income inequality and welfare generosity, and, on the other, punitiveness, have been built in both theoretical and empirical explorations in the contemporary comparative literature on the sociology of punishment. Then, I will point out the strong concentration of these explorations on national cases from the Global North as a potential limitation. From there, I will try to ‘southernize’ this debate, through three empirical exercises related to a region of the Global South, Latin America. First, I will include this region in a global comparison of clusters of countries to define whether there is an association between the levels of income inequality and welfare generosity and the levels of punitiveness, both now and in the recent past. Second, I will analyse if the same relationships exist within Latin America countries, both now and in the recent past. Finally, I will examine whether these same relationships are relevant for understanding the evolution of the levels of punitiveness in Latin America over the last three decades. Based on the results of these three exercises, I will examine the shortcomings stemming from assuming these strong statements as universal, placeless and timeless, warning that the styles of comparison that have generated them have to be taken as starting points rather than as arrival points of the analysis and stressing that our analyses about contemporary penal differences, while taking macroscopic dimensions into account, should give a strong centrality to the ‘proximate’ processes that mould penal actions and results.


2021 ◽  
Vol 923 (2) ◽  
pp. 143
Author(s):  
Jubee Sohn ◽  
Margaret J. Geller ◽  
Ho Seong Hwang ◽  
Antonaldo Diaferio ◽  
Kenneth J. Rines ◽  
...  

Abstract We apply a friends-of-friends (FoF) algorithm to identify galaxy clusters and we use the catalog to explore the evolutionary synergy between brightest cluster galaxies (BCGs) and their host clusters. We base the cluster catalog on the dense HectoMAP redshift survey (2000 redshifts deg−2). The HectoMAP FoF catalog includes 346 clusters with 10 or more spectroscopic members within the range 0.05 < z < 0.55 and with a median z = 0.29. We list these clusters and their members. We also include central velocity dispersions (σ *,BCG) for the FoF cluster BCGs, a distinctive feature of the HectoMAP FoF catalog. HectoMAP clusters with higher galaxy number density (80 systems) are all genuine clusters with a strong concentration and a prominent BCG in Subaru/Hyper Suprime-Cam images. The phase-space diagrams show the expected elongation along the line of sight. Lower-density systems include some low reliability systems. We establish a connection between BCGs and their host clusters by demonstrating that σ *,BCG /σ cl decreases as a function of cluster velocity dispersion (σ cl), in contrast, numerical simulations predict a constant σ *,BCG/σ cl. Sets of clusters at two different redshifts show that BCG evolution in massive systems is slow over the redshift range z < 0.4. The data strongly suggest that minor mergers may play an important role in BCG evolution in clusters with σ cl ≳ 300 km s−1. For lower mass systems (σ cl < 300 km s−1), major mergers may play a significant role. The coordinated evolution of BCGs and their host clusters provides an interesting test of simulations in high-density regions of the universe.


2021 ◽  
Vol 3 ◽  
pp. 1-8
Author(s):  
Giorgia Iovino

Abstract. In the last decade, the tertiary education system in Italy has shrinked and a larger heterogeneity has emerged among universities located in different areas of the country, with a strong concentration of increasingly scarce resources in a narrow and geographically concentrated number of institutions. The less developed areas, such as those in Southern Italy have been hit the most, in terms of enrolled students, academic staff, financial resources, courses offered.In this work we investigate these issues by adopting a cartographic approach. We highlight these polarizing dynamics, disentangling the possible causes. We focus, particularly, on the role of new regulatory policies and the funding mechanisms based on performance indicators as producers of inequalities.


Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6961
Author(s):  
Artur Kościuszko ◽  
Piotr Czyżewski ◽  
Mateusz Rojewski

Polypropylene (PP) belongs to the group of polymers characterized by low susceptibility to absorption of electromagnetic radiation in the infrared range (λ = 1064 nm). This research consisted of assessing the possibility of using silica waste from the metallurgic industry as an additive for PP laser marking. The modifier was introduced into the polymer matrix in the range from 1 to 10 wt%. The effects of laser radiation were assessed based on colorimetric tests and microscopic surface analysis. The mechanical properties of the composites were determined during the static tensile tests. The thermal properties were investigated via differential scanning calorimetry. It was found that the introduction of silica waste into polypropylene allows for the effective marking of sample surfaces with the use of a laser beam. The greatest contrast between the graphic symbol and the background was obtained for silica contents of 3 and 5 wt%, with the use of a low-speed laser head and a strong concentration of the laser beam. The application of silica caused an increase in the modulus of elasticity and the tensile strength of the composite samples. Increases in the crystallization temperature and the degree of crystallinity of the polymer matrix were also observed. It was found that silica waste can act as multifunctional additive for polypropylene.


Urban Studies ◽  
2021 ◽  
pp. 004209802110519
Author(s):  
Robert Musil ◽  
Florian Brand ◽  
Hannes Huemer ◽  
Maximilian Wonaschütz

This article intends to contribute to the debate on the quantification of gentrification, which is constrained by two main obstacles: firstly, the operationalisation of displacement of socially weak households, which appears as an elusive phenomenon. Secondly, the consideration of the specific urban context, in particular the regulation of the housing market. Based on a case study for Vienna, this paper introduces a new empirical approach, which does not focus on households, but on the tenement conversion of the historic housing stock. Here, the transformation as legal conversion and demolition of historic tenement houses (German: Zinshäuser) serve as an alternative indicator for the operationalisation and quantification of displacement processes. The empirical analysis of Zinshaus transformations observed for 2007-2019 for the first time provides an estimation of gentrification dynamics in Vienna. Results point to a pronounced cyclicality in transformation dynamics. Hence, spatial cluster and hotspot analyses reveal a strong concentration of Zinshaus transformations and a clear shift from central bourgeois to peripheral working-class neighbourhoods. Further, a multilinear regression model confirms the impact of Zinshaus transformations on the social dynamics in these neighbourhoods. However, data do not indicate a social shift triggered by upper-class households, but by new migrant groups and well-educated middle-class households. Beyond the case of Vienna, this analysis underlines the relevance of quantitative gentrification approaches based on housing-market segments and their conversion. It proposes applying the Zinshaus as an indicator to make the variety of the urban context visible.


Author(s):  
Andrea Zaccaro ◽  
André Riehl ◽  
Andrea Piarulli ◽  
Gaspare Alfì ◽  
Bruno Neri ◽  
...  

Nidrâ yoga is an ancient yogic practice capable of inducing altered states of consciousness characterized by deep relaxation, strong concentration, acute self-awareness, and joy. In modern contemplative neuroscience language, it is known by the name yoga nidra, and few studies have investigated its phenomenological and psychophysiological effects. Six healthy volunteers (four females aged 31–74) performed 12 yoga nidra sessions guided by an expert during a 6-day retreat. Each session consisted of 10 minutes in a resting state (baseline) followed by 2 hours of yoga nidra. Psychometric data regarding dissociative experiences (Clinician Administered Dissociative States Scale) and the state of consciousness (Phenomenology of Consciousness Inventory) were collected after baseline and yoga nidra, while high-density EEG was recorded during the entire session. During nidra sessions, no sleep hallmarks (i.e., K-complexes and sleep spindles) were detected by the EEG in any subject. Psychometric data we re analyzed using a Wilcoxon signed-rank test corrected with the false discovery rate approach for multiple comparisons. Compared to baseline, yoga nidra practice was related to: (1) increased dissociative effects (p = 0.022); (2) perception of being in an altered state of consciousness (p = 0.026); (3) alterations in perceived body image (p = 0.022); (4) increased “meaningfulness” attributed to the experience (p = 0.026); (5) reduced rational thinking (p = 0.029); and (6) reduced volitional thought control (p = 0.026). First-person experience is discussed in relation to descriptive EEG power spectral density analysis, which was performed in one subject because of severe EEG artifacts in the other recordings; that subject showed, compared to baseline: (1) early increase of alpha and beta power, followed by a progressive widespread reduction; (2) widespread early increase of theta power, followed by a progressive reduction; and (3) widespread increase of gamma power in the latest stages. The present preliminary results enrich the knowledge of yoga nidra, elucidating its phenomenology and suggesting some psychophysiological correlates that future studies may address.


Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4850
Author(s):  
Brian R. Carrick ◽  
Claire L. Seitzinger ◽  
Timothy P. Lodge

Polymer/ionic liquid systems are being increasingly explored, yet those exhibiting lower critical solution temperature (LCST) phase behavior remain poorly understood. Poly(benzyl methacrylate) in certain ionic liquids constitute unusual LCST systems, in that the second virial coefficient (A2) in dilute solutions has recently been shown to be positive, indicative of good solvent behavior, even above phase separation temperatures, where A2 < 0 is expected. In this work, we describe the LCST phase behavior of poly(benzyl methacrylate) in 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide for three different molecular weights (32, 63, and 76 kg/mol) in concentrated solutions (5–40% by weight). Turbidimetry measurements reveal a strong concentration dependence to the phase boundaries, yet the molecular weight is shown to have no influence. The critical compositions of these systems are not accessed, and must therefore lie above 40 wt% polymer, far from the values (ca. 10%) anticipated by Flory-Huggins theory. The proximity of the experimental cloud point to the coexistence curve (binodal) and the thermo-reversibility of the phase transitions, are also confirmed at various heating and cooling rates.


2021 ◽  
Author(s):  
Kyongok Kang

Abstract Many biological systems exhibit natural regulation mechanisms as necessary functions. Proteins, peptides, charged receptors, RNAs, and DNAs clearly demonstrate such varieties of structural dynamics in their biocomplexity. To understand the proper structural functionality of biomolecules, this requires integrated information from initiation, regulation, transfer and transport to desirable sustainable processes. Here, we demonstrate the orientation kinetics of stable chiral-nematic (N*) domains that are consistently formed in the suspensions of charged DNA rods at low ionic strengths. This is enhanced by large access of released dissociated condensed ions and the mobile diffusive ions of DNA rods, acting onto the perpendicular motions of the DNA rods in bulk. The quantification of collective orientations for these interacting charged DNA rods is extracted by image-time correlation (ITC) performed in Fourier transforms (FTs) for overall spectral density distributions. Three distinguishable length scales are clearly shown corresponding to the relevant motion of the N* domain in parallel, perpendicular and the optical pitch within the domains as well as the kinetics of local distributions in FTs. Particularly strong concentration transitions are confirmed by replica symmetry breaking of elastic deformations in N* domains in terms of the average twist angle and the order parameter. This work can be interesting for sufficient cooling of the given concentration of charged DNA rods, at low ionic strengths (below the critical value), mimicking super-cooled liquid and orientation glass in other biomacromolecules.


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