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15322. The space of compact operators contains $c_0$ when a noncompact operator is suitably factorized
- Creator:
- Emmanuele, Giovanni and John, Kamil
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- spaces of linear operators, copies of $c_0$, and approximation properties
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15323. The spatial correlation between the spread of COVID-19 and vulnerable urban areas in Santiago de Chile
- Creator:
- Vergara-Perucich, Francisco, Correa-Parra, Juan, and Aguirre-Nuñez, Carlos
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- housing in developing countries, urban policy and planning, residential context of health, and housing economics
- Language:
- English
- Description:
- This article identifies the spatial correlation between the social determinants of health in the housing area (housing prices, overcrowding, poor-quality building materials, and household socioeconomic vulnerability) and the spread of COVID-19 in Santiago de Chile. The research used data from the 2017 Census conducted by the National Institute of Statistics of Chile and data on confirmed cases of COVID-19 (PCR) by communes provided by/obtained from Chile’s Ministry of Health. The article provides a two-fold examination/analysis of the spatial correlation using the Pearson measure to observe how the virus spread from areas with high-quality housing in the early stage of the contagion to then become concentrated in areas with low-quality of housing. The second examination/analysis is a multiple linear regression to identify the housing factors that inform virus propagation. The test results show that of the four social determinants of health relating to housing assessed here, housing prices is the variable that best predicts how the social determinants of health based on housing explain the progress of the pandemic for the Santiago case, following the collinearity factors according to the data used in this study. The conclusions suggest that public policy should treat housing quality as a factor in public health and health risks that needs to be addressed with a transdisciplinary approach to urban planning in Chile.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15324. The spatial distribution of leaf galls of Mikiola fagi (Diptera: Cecidomyiidae) and Neuroterus quercusbaccarum (Hymenoptera: Cynipidae) in the canopy of a Central European mixed forest
- Creator:
- Kampichler, Christian and Teschner, Markus
- Type:
- article, model:article, and TEXT
- Subject:
- Mikiola fagi, Neuroterus quercusbaccarum, galls, spatial distribution, host preference, canopy, oak, and beech
- Language:
- English
- Description:
- Despite their wide distribution and frequent occurrence, the spatial distribution patterns of the well-known gall-inducing insects Mikiola fagi (Hartig) and Neuroterus quercusbaccarum (L.) in the canopies of mature trees are poorly described. We made use of the Swiss Canopy Crane (SCC) near Basel, Switzerland, to gain access to the canopy of a mixed temperate forest up to a height of 35 m. Within one and a half days we scanned 6,750 beech leaves and 6,000 oak leaves. M.fagi showed a distinct vertical zonation with highest abundance in the top-most parts of the canopy as well as a significant aggregation on particular trees. N. quercusbaccarum showed an even more pronounced preference for particular trees and a general preference for Quercus robur over Q. petraea. In contrast to M. fagi, no vertical zonation could be detected. We think that both gall-inducing species have greater powers of dispersal than formerly assumed since they overwinter on the forest floor and yet are able to 1) gain access to the entire canopy, 2) show preference for certain host trees. We found little evidence for the phenological synchrony hypothesis proposed to explain the intertree distribution of N. quercusbaccarum. The highest density of M. fagi galls was in those parts of the canopy exposed to high solar radiation; their host choice is probably determined by micro-climatological factors. The consequences of the distribution patterns of N. quercusbaccarum and M. fagi for their ecological interactions with the host-plant, inquilines and parasitoids (e.g., canopy-layer specific performance linked to plant chemistry, density-dependent parasitism) need now to be subjected to further scientific investigation.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15325. The spectra of general differential operators in the direct sum spaces
- Creator:
- Ibrahim, Sobhy El-sayed
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- quasi-differential expressions, essential spectra, joint field of regularity, regularly solvable operators, and direct sum spaces
- Language:
- English
- Description:
- In this paper, the general ordinary quasi-differential expression $M_p$ of $n$-th order with complex coefficients and its formal adjoint $M_p^+$ on any finite number of intervals $I_p=(a_p,b_p)$, $p=1,\dots ,N$, are considered in the setting of the direct sums of $L_{w_p}^2(a_p,b_p)$-spaces of functions defined on each of the separate intervals, and a number of results concerning the location of the point spectra and the regularity fields of general differential operators generated by such expressions are obtained. Some of these are extensions or generalizations of those in a symmetric case in [1], [14], [15], [16], [17] and of a general case with one interval in [2], [11], [12], whilst others are new.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15326. The spread of Islam in the Ottoman Balkans: revisiting Bulliet´s method on religious conversion
- Creator:
- Radushev, Evgeni
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- conversion to Islam, Ottoman Balkans, Pomaks, and Rhodope mountains
- Language:
- English
- Description:
- The first chronologically comprehensive and conceptually sound view of conversion to Islam was that offered by R. W. Bulliet. His Conversion to Islam in the Medieval Period, published in 1979, is of great importance to the study of the conversion process and its ethno-religious and social consequences. Qualifying R. W. Bulliet’s method as “an original, bold and provocative work worthy of attention,” it should be mentioned that his study has been criticized on many grounds. Some historians conceive it, above all, as “food for thought,” its conclusions being reliable primarily with respect to medieval Iran only, due to the great limitations of the source base. I would maintain, however, that given the sufficient amounts of available empirical data, R. W. Bulliet’s research technique is reliable and meaningful. In my paper I have attempted to show through the results of my research that his quantitative model and timetable of conversion to Islam are valid in relation to the investigation of the dynamics of ethno-religious processes in the Ottoman Balkans. The similar results revealed in both this researcher’s theoretically drawn model and the curve of conversion that I obtained when using a sufficient quantity of numerical data from the Balkans, prove that Bulliet’s method is applicable in investigating the diffusion of Islam in its broadest chronological and territorial scope.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15327. The stability analysis of a discretized pantograph equation
- Creator:
- Jánský, Jiří and Kundrát, Petr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- pantograph equation, numerical solution, and stability
- Language:
- English
- Description:
- The paper deals with a difference equation arising from the scalar pantograph equation via the backward Euler discretization. A case when the solution tends to zero but after reaching a certain index it loses this tendency is discussed. We analyse this problem and estimate the value of such an index. Furthermore, we show that the utilized proof technique enables us to investigate some other numerical formulae, too.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15328. The stability of parameter estimation of fuzzy variables
- Creator:
- Hong, Dug Hun
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fuzzy variables, parameter estimation, consistency, MSE, and stability of estimation
- Language:
- English
- Description:
- Recently, the parameter estimations for normal fuzzy variables in the Nahmias' sense was studied by Cai [4]. These estimates were also studied for general T-related, but not necessarily normal fuzzy variables by Hong [10] In this paper, we report on some properties of estimators that would appear to be desirable, including unbiasedness. We also consider asymptotic or "large-sample" properties of a particular type of estimator.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15329. The Stegana undulata species group (Diptera: Drosophilidae) from the Oriental Region, with molecular phylogenetic analysis of the Chinese species
- Creator:
- Lu, Jin-Ming, Gao, Jian-Jun, Chen, Xi-Peng, and Chen, Hong-Wei
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Asie jihovýchodní, Asia, Southeastern, Drosophilidae, systematics, molecular phylogeny, mitochondrial DNA, Stegana undulata group, Steganina, 2, and 59
- Language:
- English
- Description:
- The Stegana undulata species group is revised and eight new species described: S. (Steganina) flaviclypeata Chen & Chen, sp. n., S. (S.) flavipalpata Chen & Chen, sp. n., S. (S.) leucothorax Chen & Chen, sp. n., S. (S.) melanocheilota Chen & Chen, sp. n. and S. (S.) melanothorax Chen & Chen, sp. n. from southern China, and S. (S.) flaviscutellata Chen & Chen, sp. n., S. (S.) nigriclypeata Chen & Chen, sp. n. and S. (S.) nigripalpata Chen & Chen, sp. n. from eastern Malaysia. A key to all the species examined based on morphological data is provided. Based on DNA sequence data of the mitochondrial ND2 and COI genes, the relationship among six Chinese species of the undulata group and that of the S. coleoptrata and S. nigrolimbata species groups of the same subgenus is investigated, using S. emeiensis of the subgenus Stegana s. str. as an out-group. and Jin-Ming LU, Jian-Jun GAO, Xi-Peng CHEN, Hong-Wei CHEN.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15330. The steroid metabolome in men with mood and anxiety disorders
- Creator:
- Michaela Dušková, Hill, M., Marie Bičíková, Šrámková, M., Daniela Řípová, Mohr, P., and Luboslav Stárka
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, steroidní hormony, steroid hormons, allopregnanolone, dehydroepiandrosterone, affective depression, anxiosity, steroid sulfates, steroid conjugates, 14, and 612
- Language:
- English
- Description:
- The mood and behavior of individuals result from an orchestra of many factors. Among them steroids play an important role; however, only several common hormones have been investigated in this respect. It has been demonstrated that some steroid metabolites long considered merely the products of steroid hormone metabolism in fact possess considerable activity in the CNS. For this reason we studied the steroid metabolome including 50 analytes in 20 men with depression, 20 men with anxiety and 30 healthy controls. Significant differences were found not only between controls and men with either depression or anxiety, but also between men with depression and anxiety. Particularly striking were those steroids until now not generally associated with depression or anxiety, namely conjugated steroid forms, especially sulfates., M. Dušková, M. hill, M. Bičíková, M. Šrámková, D. Řípová, P. Mohr, L. Stárka., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public