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1
Sauer, Niko, e Joy E. Singleton. "Evolution operators related to semi-groups of class (A)". Semigroup Forum 35, n. 1 (dicembre 1986): 317–35. http://dx.doi.org/10.1007/bf02573114.
2
Huang, Qing, e Renat Zhdanov. "Group classification of nonlinear evolution equations: Semi-simple groups of contact transformations". Communications in Nonlinear Science and Numerical Simulation 26, n. 1-3 (settembre 2015): 184–94. http://dx.doi.org/10.1016/j.cnsns.2015.01.009.
3
Zhdanov, R., e V. Lahno. "Group classification of the general second-order evolution equation: semi-simple invariance groups". Journal of Physics A: Mathematical and Theoretical 40, n. 19 (24 aprile 2007): 5083–103. http://dx.doi.org/10.1088/1751-8113/40/19/010.
4
Farhang, Amin, Habib G. Khosroshahi, Gary A. Mamon, Ali A. Dariush e Mojtaba Raouf. "Evolution of Compact and Fossil Groups of Galaxies from Semi-analytical Models of Galaxy Formation". Astrophysical Journal 840, n. 1 (4 maggio 2017): 58. http://dx.doi.org/10.3847/1538-4357/aa6b00.
5
Ilchev, Alexander, Rueben Pfukwa, Lebohang Hlalele, Marica Smit e Bert Klumperman. "Improved control through a semi-batch process in RAFT-mediated polymerization utilizing relatively poor leaving groups". Polymer Chemistry 6, n. 46 (2015): 7945–48. http://dx.doi.org/10.1039/c5py01293g.
Abstract (sommario):
The negative effect that a RAFT agent with a poor leaving group has on the evolution of molecular dispersity in a RAFT-mediated polymerization was shown to be mitigated by performing the polymerization in semi-batch mode.
6
Díaz-Giménez, E., A. Zandivarez e G. A. Mamon. "Compact groups from semi-analytical models of galaxy formation – II. Different assembly channels". Monthly Notices of the Royal Astronomical Society 503, n. 1 (24 febbraio 2021): 394–405. http://dx.doi.org/10.1093/mnras/stab535.
Abstract (sommario):
ABSTRACT We study the formation of over 6000 compact groups (CGs) of galaxies identified in mock redshift-space galaxy catalogues built from semi-analytical models of galaxy formation (SAMs) run on the Millennium Simulations. We select CGs of four members in our mock SDSS galaxy catalogues and, for each CG, we trace back in time the real-space positions of the most massive progenitors of their four galaxies. By analysing the evolution of the distance of the galaxy members to the centre of mass of the group, we identify four channels of CG formation. The classification of these assembly channels is performed with an automatic recipe inferred from a preliminary visual inspection and based on the orbit of the galaxy with the fewest number of orbits. Most CGs show late assembly, with the last galaxy arriving on its first or second passage, while only 10–20 per cent form by the gradual contraction of their orbits by dynamical friction, and only a few per cent forming early with little subsequent contraction. However, a SAM from a higher resolution simulation leads to earlier assembly. Assembly histories of CGs also depend on cosmological parameters. At similar resolution, CGs assemble later in SAMs built on parent cosmological simulations of high density parameter. Several observed properties of mock CGs correlate with their assembly history: early-assembling CGs are smaller, with shorter crossing times, and greater magnitude gaps between their brightest two members, and their brightest galaxies have smaller spatial offsets and are more passive.
7
Hubal, Halyna M. "The generalized kinetic equation for symmetric particle systems". MATHEMATICA SCANDINAVICA 110, n. 1 (1 marzo 2012): 140. http://dx.doi.org/10.7146/math.scand.a-15201.
Abstract (sommario):
The generalized kinetic equation is obtained for symmetric system of many particles interacting via a pair potential. A representation of a solution of the Cauchy problem for the BBGKY hierarchy is used in the form of an expansion over particle groups whose evolution is governed by the cumulants (semi-invariants).
8
Fukunaga, Kenji, e Makoto Kawase. "Crop Evolution of Foxtail Millet". Plants 13, n. 2 (12 gennaio 2024): 218. http://dx.doi.org/10.3390/plants13020218.
Abstract (sommario):
Studies on the domestication, genetic differentiation, and crop evolution of foxtail millet are reviewed in this paper. Several genetic studies were carried out to elucidate the genetic relationships among foxtail millet accessions originating mainly from Eurasia based on intraspecific hybrid pollen semi-sterility, isozymes, DNA markers, and single-nucleotide polymorphisms. Most studies suggest that China is the center of diversity of foxtail millet, and landraces were categorized into geographical groups. These results indicate that this millet was domesticated in China and spread over Eurasia, but independent origin in other regions cannot be ruled out. Furthermore, the evolution of genes was reviewed (i.e., the Waxy gene conferring amylose content in the endosperm, the Si7PPO gene controlling polyphenol oxidase, the HD1 and SiPRR37 genes controlling heading time, the Sh1 and SvLes1 genes involved in grain shattering, and the C gene controlling leaf sheath pigmentation), and the variation and distribution of these genes suggested complex patterns of evolution under human and/or natural selection.
9
Kuang, Yutong. "Synchronic Variation and Diachronic Evolution of Tone Patterns in Kunming Dialect". International Journal of Languages, Literature and Linguistics 8, n. 4 (dicembre 2022): 295–301. http://dx.doi.org/10.18178/ijlll.2022.8.4.365.
Abstract (sommario):
An acoustic experiment was conducted to analyze the tonal patterns of single characters in the Kunming dialect. The experimental results show that the Kunming dialect has a semi-high flat tone for the first tone, a low descending tone for the second tone, a high descending tone for the third tone, and a low tone for the fourth tone. The first and third tones are both high, while the second and fourth are both low tones, as opposed to the tonal patterns of "flat" and "low". The newer Kunming dialects show variation. The first tone starts and ends at a higher level, the third tone's bent section disappears, and the fourth tone starts and ends at a lower level, with a shorter tone duration. The variation in tone pattern starts in the middle-aged group in the old urban, and the degree of variation is female > male, old urban > old suburban, and the youth and middle-aged group > senior group, respectively. The female tone pattern has more similar vocal tone characteristics to those in the middle-aged and youth groups.
10
Prialnik, Dina. "The Cyclic Evolution of Classical Novae". International Astronomical Union Colloquium 122 (1990): 351–60. http://dx.doi.org/10.1017/s0252921100068846.
Abstract (sommario):
The cyclic evolution of classical novae (CN) cannot be observed, as in the case of recurrent or dwarf novae. The duration of a typical cycle may range from a few thousand to a few 105 years. Thus we have to rely on theoretical studies for understanding the periodic outbursts — due to thermonuclear runaways (TNR) — on the surface of accreting white dwarfs (WD). One may distinguish between two kinds of studies: a) detailed investigations of a specific aspect or a particular evolutionary phase; b) studies which emphasize the cyclic behavior of novae and their long-term evolution. The latter, which form the subject of this brief review, may be divided into four groups, each adopting a different approach to the problem:1.Steady-state (semi-analytic) solutions;2.One- (or two-) zone models;3.Quasi-static (and/or steady burning) numerical calculations;4.Full-scale hydrodynamic evolutionary computations.
11
GANZHORN, JÖRG U. "Soil Consumption of Two Groups of Semi-free-ranging Lemurs {Lemur catta and Lemur fulvus)". Ethology 74, n. 2 (26 aprile 2010): 146–54. http://dx.doi.org/10.1111/j.1439-0310.1987.tb00927.x.
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HORNOS, JOSÉ EDUARDO M., YVONE M. M. HORNOS e MICHAEL FORGER. "SYMMETRY AND SYMMETRY BREAKING: AN ALGEBRAIC APPROACH TO THE GENETIC CODE". International Journal of Modern Physics B 13, n. 23 (20 settembre 1999): 2795–885. http://dx.doi.org/10.1142/s021797929900268x.
Abstract (sommario):
We give a comprehensive review of the algebraic approach to the genetic code originally proposed by two of the present authors, which aims at explaining the degeneracies encountered in the genetic code as the result of a sequence of symmetry breakings that have occurred during its evolution. We present the relevant background material from molecular biology and from mathematics, including the representation theory of (semi) simple Lie groups/algebras, together with considerations of general nature.
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Baßmann, Björn, Lisa Hahn, Alexander Rebl, Lisa Carolina Wenzel, Marc-Christopher Hildebrand, Marieke Verleih e Harry Wilhelm Palm. "Effects of Stocking Density, Size, and External Stress on Growth and Welfare of African catfish (Clarias gariepinus Burchell, 1822) in a Commercial RAS". Fishes 8, n. 2 (26 gennaio 2023): 74. http://dx.doi.org/10.3390/fishes8020074.
Abstract (sommario):
The effects of semi-intensive (100 kg m−3), intensive (200 kg m−3), and super-intensive (400 kg m−3) stocking densities on the growth and welfare of African catfish (Clarias gariepinus) were investigated under commercial production conditions. Plasma cortisol, glucose, and selected transcripts following a stress challenge, lactate, as well as skin lesions, were analyzed at regular intervals (from 12 g juveniles to 1.5–2.0 kg). The fish grew well, but after 23 weeks, the semi-intensively stocked fish had a mean final weight of 1,830.5 g, significantly higher than the super-intensively stocked fish with 1,615.4 g, and considerably higher than the intensively stocked fish with 1,664.8 g (p > 0.05). Cortisol and glucose responses significantly differed between stressed and unstressed fish, but not between treatment groups. An unforeseen external stressor (nearby demolition noise) caused stress responses among all treatment groups, but was similarly coped with. Mortality ranged between 3.8–9.2%. In the juveniles, skin lesions were reduced under intensive or super-intensive densities, with the least under semi-intensive densities in outgrown fish. Expression profiles of 22 genes were compared in the spleen at semi-intensive and super-intensive densities. The transcript concentrations of most genes remained unchanged, except for slc39a8 and mtf1, which were significantly downregulated in stressed catfish under semi-intensive conditions. We demonstrated that African catfish growth performance and welfare depend on age and stocking density, also reacting to demolition noise. This supports farm management to optimize stocking densities during the grow-out of African catfish in RAS and suggests avoiding external stress.
14
Ding, Yanqiong, Yazhou Xu e Huiquan Miao. "A Seismic Checking Method of Engineering Structures Based on the Stochastic Semi-Physical Model of Seismic Ground Motions". Buildings 12, n. 4 (14 aprile 2022): 488. http://dx.doi.org/10.3390/buildings12040488.
Abstract (sommario):
A seismic checking method of engineering structures based on the stochastic semi-physical model of seismic ground motions is developed. Four groups of stochastic ground motions are generated using the stochastic semi-physical model of seismic ground motions. In conjunction with the probability density evolution method (PDEM) and the idea of the equivalent extreme-value event, the dynamic reliabilities of an engineering structure are evaluated. The dynamic reliability of the structure is taken as an index for seismic checking. A five-story reinforced concrete frame structure is analyzed using both the response spectrum method and the proposed method. Some features of the instantaneous probability density function (PDF) and its evolution, the extreme value distribution, and the dynamic reliability are discussed and compared with the results of the response spectrum method in the Chinese seismic code. The seismic checking results of the response spectrum method show that the structure is safe, while the results of the proposed method reveal a failure probability as high as 35.39%. Moreover, the structure has such different reliabilities when it is excited by different groups of simulated seismic ground motions. It reveals that a structure designed according to the seismic code may carry a high risk of failure. The proposed method provides a more accurate way for the evaluation of the reliabilities of engineering structures.
15
Ramesh Khaparde, Amit, Ramesh Poondi Sundarasamy, Sathiyaraj Rajendran, Amrita Ticku e Arunkumar Palanichamy. "Analysis of new differential evolution variants to solve multi-modal problems". IAES International Journal of Artificial Intelligence (IJ-AI) 12, n. 3 (1 settembre 2023): 1352. http://dx.doi.org/10.11591/ijai.v12.i3.pp1352-1359.
Abstract (sommario):
Differential evolution algorithm requires diversified population to solve multi- modalproblems. DE supports non-distributed population. Differential evolution algorithm (DE) versions include differential evolution algorithm with best selection method and species evolution (DESBS) and differential evolution algorithm with hierarchical fair competition modal (HFCDE). This article analyzed the efficiency of HFCDE and DESBS to solve the multi-modal s’ problems. HFCDE and DESBS support non-distributed population structured. HFCDE starts with set of feasible solution then it distributed them in the different hierarchy. HFCDE provides the fair competition. DESBS is another semi distributed, differential evolution algorithm.It starts with set of feasible solutions (population). Later it identifies the niches and create the sub-groups within population. Both HFCDE and DESBS have outperformed the other variant of state-of-art variants of DE. Here, the performance of DESBS and the HFCDE are rigorously tested on the multimodal problems. The success of DESBS over HFCDE in multi-modal difficulties managed to overcome the phenomena of elitism to resolve the complex problems, it has been observed that DESBS performs better than HFCDE in complex multi-modal scenarios.
16
Bell, Cameron P. M., Eric E. Mamajek e Tim Naylor. "The Isochronal Age Scale of Young Moving Groups in the Solar Neighbourhood". Proceedings of the International Astronomical Union 10, S314 (novembre 2015): 41–48. http://dx.doi.org/10.1017/s1743921315006213.
Abstract (sommario):
AbstractWe present a self-consistent, absolute isochronal age scale for young (≲ 200 Myr), nearby (≲ 100 pc) moving groups, which is consistent with recent lithium depletion boundary ages for both the β Pic and Tucana-Horologium moving groups. This age scale was derived using a set of semi-empirical pre-main-sequence model isochrones that incorporate an empirical colour-Teffrelation and bolometric corrections based on the observed colours of Pleiades members, with theoretical corrections for the dependence on logg. Absolute ages for young, nearby groups are vital as these regions play a crucial role in our understanding of the early evolution of low- and intermediate-mass stars, as well as providing ideal targets for direct imaging and other measurements of dusty debris discs, substellar objects and, of course, extrasolar planets.
17
Leishman, Michelle R., e Mark Westoby. "Classifying Plants into Groups on the Basis of Associations of Individual Traits--Evidence from Australian Semi-Arid Woodlands". Journal of Ecology 80, n. 3 (settembre 1992): 417. http://dx.doi.org/10.2307/2260687.
18
Jussila, Japo, Jeff Jago, Elena Tsvetnenko, Bob Dunstan e Louis H. Evans. "Total and differential haemocyte counts in western rock lobsters (Panulirus cygnus George) under post-harvest stress". Marine and Freshwater Research 48, n. 8 (1997): 863. http://dx.doi.org/10.1071/mf97216.
Abstract (sommario):
Total and differential haemocyte counts (THCs and DHCs) were obtained from 36 white and 36 red western rock lobsters (Panulirus cygnus) that had experienced stress during capture and transportation. The lobsters were divided into three different groups on the basis of their holding time in the factory tanks and their health status (fresh arrivals, healthy and moribund). THCs were obtained with a haemocytometer from fresh haemolymph stained with gentian violet. THCs ranged from 2.5 106 to 15.9 106 cells mL-1 in the three groups, being lowest in the moribund lobsters. DHCs were obtained from haemolymph smears stained with both Giemsa and May–GrÜnwald. Three major haemocyte groups could be identified in lobster haemolymph: hyalinocytes, semi-granulocytes and granulocytes. The proportion of hyalinocytes in the three lobster groups ranged from 29.1% to 37.0%, that of semi- granulocytes from 51.1% to 62.9%, and that of granulocytes from 5.1% to 13.1%. The proportion of granulocytes declined in lobsters after they were held for 16 h in the factory tanks and was lowest in moribund lobsters. The results show that THCs and DHCs may be useful in assessing stress or health status in the western rock lobster or other lobsters.
19
Vasanthy, G., B. S. Venkatachala e S. A. J. Pocock. "The evolution of angiospermid pollen characteristics: conjectures and queries". Journal of Palaeosciences 38 (31 dicembre 1989): 131–46. http://dx.doi.org/10.54991/jop.1989.1647.
Abstract (sommario):
The origin and evolution of different exine layers of palynofossils is analysed in the light of accumulating ultrastructural data. Semi-diagramatic illustrations based on the published TEM results of various exine types representing a cross section of extinct and extant plant groups are given for easy reference and comprehension. Some of the important palynological questions and issues discussed in the present work are imprecise use to describe the infra-tectum of pollen, of the flexible term "granular" that often leads to erroneous derivations and conclusions; ontogenetic differences between the apparently similar complexly alveolate columellate sexine types of gymnosperms and angiosperms respectively; independent evolution of columellar complexity in unrelated taxa: role of ubiquitous white lines in the exines of extinct and extant spores and pollen and adaptive rather than phylogenetic significance of sacci in progymnosperms, gymnosperms and angiosperms. Despite recognition of angiospermid pollen characteristics especially in tectally reticulate and columellate pollen of Triassic (Cornet, 1979, 1985, 1989; Pocock & Vasanthy, 1988; Pocock, Vasanthy & Venkatachala. 1988) the pre-Cretaceous origin of angiosperm still remains an open question.
20
Jia, Jinzhang, Yinghuan Xing, Bin Li, Dan Zhao, Yumo Wu, Yinuo Chen e Dongming Wang. "Study on the Occurrence Difference of Functional Groups in Coals with Different Metamorphic Degrees". Molecules 28, n. 5 (28 febbraio 2023): 2264. http://dx.doi.org/10.3390/molecules28052264.
Abstract (sommario):
In order to quantitatively study the difference in occurrence content of functional groups in coals with different metamorphic degrees, the samples of long flame coal, coking coal, and anthracite of three different coal ranks were characterized by FTIR and the relative content of various functional groups in different coal ranks was obtained. The semi-quantitative structural parameters were calculated, and the evolution law of the chemical structure of the coal body was given. The results show that with the increase in the metamorphic degree, the substitution degree of hydrogen atoms on the benzene ring in the aromatic group increases with the increase in the vitrinite reflectance. With the increase in coal rank, the content of phenolic hydroxyl, carboxyl, carbonyl, and other active oxygen-containing groups gradually decreased, and the content of ether bonds gradually increased. Methyl content increased rapidly first and then increased slowly, methylene content increased slowly first and then decreased rapidly, and methylene content decreased first and then increased. With the increase in vitrinite reflectance, the OH-π hydrogen bond gradually increases, the content of hydroxyl self-association hydrogen bond first increases and then decreases, the oxygen-hydrogen bond of hydroxyl ether gradually increases, and the ring hydrogen bond first significantly decreases and then slowly increases. The content of the OH-N hydrogen bond is in direct proportion to the content of nitrogen in coal molecules. It can be seen from the semi-quantitative structural parameters that with the increase in coal rank, the aromatic carbon ratio fa, aromatic degree AR and condensation degree DOC increase gradually. With the increase in coal rank, A(CH2)/A(CH3) first decreases and then increases, hydrocarbon generation potential ‘A’ first increases and then decreases, maturity ‘C’ first decreases rapidly and then decreases slowly, and factor D gradually decreases. This paper is valuable for analyzing the occurrence form of functional groups in different coal ranks and clarifying the evolution process of structure in China.
21
Pinho, P., M. R. Theobald, T. Dias, Y. S. Tang, C. Cruz, M. A. Martins-Loução, C. Máguas, M. Sutton e C. Branquinho. "Critical loads of nitrogen deposition and critical levels of atmospheric ammonia for semi-natural Mediterranean evergreen woodlands". Biogeosciences 9, n. 3 (28 marzo 2012): 1205–15. http://dx.doi.org/10.5194/bg-9-1205-2012.
Abstract (sommario):
Abstract. Nitrogen (N) has emerged in recent years as a key factor associated with global changes, with impacts on biodiversity, ecosystems functioning and human health. In order to ameliorate the effects of excessive N, safety thresholds such as critical loads (deposition fluxes) and levels (concentrations) can be established. Few studies have assessed these thresholds for semi-natural Mediterranean ecosystems. Our objective was therefore to determine the critical loads of N deposition and long-term critical levels of atmospheric ammonia for semi-natural Mediterranean evergreen woodlands. We have considered changes in epiphytic lichen communities, one of the most sensitive comunity indicators of excessive N in the atmosphere. Based on a classification of lichen species according to their tolerance to N we grouped species into response functional groups, which we used as a tool to determine the critical loads and levels. This was done for a Mediterranean climate in evergreen cork-oak woodlands, based on the relation between lichen functional diversity and modelled N deposition for critical loads and measured annual atmospheric ammonia concentrations for critical levels, evaluated downwind from a reduced N source (a cattle barn). Modelling the highly significant relationship between lichen functional groups and annual atmospheric ammonia concentration showed the critical level to be below 1.9 μg m−3, in agreement with recent studies for other ecosystems. Modelling the highly significant relationship between lichen functional groups and N deposition showed that the critical load was lower than 26 kg (N) ha−1 yr−1, which is within the upper range established for other semi-natural ecosystems. Taking into account the high sensitivity of lichen communities to excessive N, these values should aid development of policies to protect Mediterranean woodlands from the initial effects of excessive N.
22
Hegade, Prakash, A. M. Abirami, Rashpinder Kaur e Ashok Shettar. "Understanding Technological Evolution in Teaching: A Qualitative Data Analysis". Journal of Engineering Education Transformations 37, IS2 (1 gennaio 2024): 707–12. http://dx.doi.org/10.16920/jeet/2024/v37is2/24110.
Abstract (sommario):
Abstract—Every evolution, rooted in its principles, presents a time-relevant paradigm shift. In the regards, technological evolution has been a significant milestone in the journey of educational contributions. It has today become an integral part of the education eco-system. While generation-z students are characteristically tech-savvy, at the same time it questions the caliber of the faculty to address the needs of these students. To understand the evolution of teaching pedagogies of the classroom, a qualitative study was conducted with Connectivism as the underlying theoretical framework. Through the semi-structured interviews, twenty seven faculty were interviewed with five questions. The first round of coding was carried out using the descriptive and vivo methods and second was carried out using the focused coding. Five themes have been discussed from the round one coding and summarized using the round two. The paper presents the results and discussion of this qualitative study and opens the potential space for future technology-related research questions. Writing learning outcomes, evolving classrooms and selecting technology have been discussed with respect to technological implications. The study concludes that the research groups need to develop philosophies by integrating the technology into the learning styles. Keywords—Connectivism; Education; Evolution; Teacher; Technology.
23
Hampson, B. A., M. A. Zabek, C. C. Pollitt e B. Nock. "Health and behaviour consequences of feral horse relocation". Rangeland Journal 33, n. 2 (2011): 173. http://dx.doi.org/10.1071/rj10075.
Abstract (sommario):
Despite ongoing projects involving the breeding and release of equids into semi-wild and wild environments, insufficient information is available in the literature that describes strategies used by equids to adapt and survive in a novel environment. The aim of this study was to assess the ability of naïve, feral Equus caballus (horse) mares to cope in a novel feral horse environment and investigate possible reasons why some may not survive this challenge. Four mares taken from a semi-arid desert environment remained in good health but significantly changed their movement behaviour pattern when surrounded by prime grazing habitat in a mesic temperate grassland. Three of the four mares captured from the prime grazing habitat and released in the semi-arid desert habitat died, apparently due to stress and/or starvation, within 8 weeks of release. The fourth mare survived 4 months but lost considerable weight. The group of mares relocated to the semi-arid desert environment had difficulty adapting to relocation and did not take up the movement behaviour strategy of local horses, which required long distance treks from a central water hole to distant feeding areas at least 15 km away. The movement behaviour, range use and health consequences of relocating equids may be of interest to wildlife ecologists, animal behaviourists and horse welfare groups. The observations may be used to guide those intending on relocating managed domestic and native horses to novel habitats.
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Vázquez-Mata, J. A., J. Loveday, S. D. Riggs, I. K. Baldry, L. J. M. Davies, A. S. G. Robotham, B. W. Holwerda et al. "Galaxy and mass assembly: luminosity and stellar mass functions in GAMA groups". Monthly Notices of the Royal Astronomical Society 499, n. 1 (21 settembre 2020): 631–52. http://dx.doi.org/10.1093/mnras/staa2889.
Abstract (sommario):
ABSTRACT How do galaxy properties (such as stellar mass, luminosity, star formation rate, and morphology) and their evolution depend on the mass of their host dark matter halo? Using the Galaxy and Mass Assembly group catalogue, we address this question by exploring the dependence on host halo mass of the luminosity function (LF) and stellar mass function (SMF) for grouped galaxies subdivided by colour, morphology, and central/satellite. We find that spheroidal galaxies in particular dominate the bright and massive ends of the LF and SMF, respectively. More massive haloes host more massive and more luminous central galaxies. The satellites LF and SMF, respectively, show a systematic brightening of characteristic magnitude, and increase in characteristic mass, with increasing halo mass. In contrast to some previous results, the faint-end and low-mass slopes show little systematic dependence on halo mass. Semi-analytic models and simulations show similar or enhanced dependence of central mass and luminosity on halo mass. Faint and low-mass simulated satellite galaxies are remarkably independent of halo mass, but the most massive satellites are more common in more massive groups. In the first investigation of low-redshift LF and SMF evolution in group environments, we find that the red/blue ratio of galaxies in groups has increased since redshift z ≈ 0.3 relative to the field population. This observation strongly suggests that quenching of star formation in galaxies as they are accreted into galaxy groups is a significant and ongoing process.
25
Lumineau, Sophie, Catherine Guyomarc'h e Jean-Pierre Richard. "Ultradian Rhythm of Activity in Japanese Quail Groups under Semi-Natural Conditions during Ontogeny: Functional Aspects and Relation to Circadian Rhythm". Biological Rhythm Research 32, n. 3 (luglio 2001): 373–400. http://dx.doi.org/10.1076/brhm.32.3.373.1339.
26
Kean, Kim J., Davide Foffa, Michela M. Johnson, Mark T. Young, Gert Greitens e Stephen L. Brusatte. "First and most northern occurrence of a thalattosuchian crocodylomorph from the Jurassic of the Isle of Skye, Scotland". Scottish Journal of Geology 57, n. 1 (24 novembre 2020): sjg2020–013. http://dx.doi.org/10.1144/sjg2020-013.
Abstract (sommario):
The Jurassic was a key interval for the evolution of dinosaurs, crocodylomorphs and many other vertebrate groups. In recent years, new vertebrate fossils have emerged from the Early–Middle Jurassic of the Isle of Skye, Scotland; however, much more is known about Skye's dinosaur fauna than its crocodylomorphs. Here we report new crocodylomorph material collected from Jurassic marine deposits at Prince Charlie's Cave on the NE coast of Skye. The specimen is a small cobble containing postcranial elements from an individual that is considerably larger in size than previous crocodylomorphs described from Skye. Based on features of the vertebrae and osteoderms, the specimen is assigned to Thalattosuchia, an extinct clade of semi-aquatic/pelagic crocodylomorphs. Specifically, the sub-circular and bean-shaped pit ornamentation on the dorsal surface of the osteoderms in alternating rows suggests affinities with the semi-aquatic lineage Teleosauroidea. Although the ornamentation pattern on the osteoderms is most similar to Macrospondylus (‘Steneosaurus’) bollensis, we conservatively assign the specimen to Teleosauroidea indeterminate. Regardless of its precise affinities and fragmentary nature, the specimen is the first thalattosuchian discovered in Scotland and is the most northerly reported Jurassic thalattosuchian globally, adding to our understanding of the palaeobiogeography and evolution of this group.Thematic collection: This article is part of the Early Career Research collection available at: https://www.lyellcollection.org/cc/SJG-early-career-research
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Thurairajah, Kalyani. "“Who are we without the war?”: The evolution of the Tamil ethnic identity in post-conflict Sri Lanka". Ethnicities 20, n. 3 (12 maggio 2019): 564–86. http://dx.doi.org/10.1177/1468796819846960.
Abstract (sommario):
Studies of post-conflict societies have often focused on inter-ethnic group dynamics following the end of conflict, specifically the process of reconciliation between groups, or resurgence of violence across groups. This paper focuses on intra-ethnic differences with respect to defining ethnic identity. This paper will examine how the end of the Sri Lankan ethnic conflict created cleavages amongst Sri Lankan Tamils with respect to how they define their ethnic identity and their ethnic group. Drawing upon 66 semi-structured interviews conducted in three regions of Sri Lanka, this paper presents three perspectives that were held among Tamils in post-conflict Sri Lanka. The first perspective was that the end of the ethnic conflict led to a loss in the fundamental tenets of the Tamil ethnic identity. The second perspective considered the promotion of a distinct Tamil ethnic identity to be a gateway to conflict. The third perspective articulated that the end of the ethnic conflict meant that the Tamil ethnic identity could move forward in a more cosmopolitan direction. The findings of this study demonstrate the importance of considering the social construction of ethnic identities, and their implications on post-conflict reconstruction.
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Zhang, Zewen, Xiaohui Li, Guiwei Zou e Hongwei Liang. "Molecular Characterization and Response of Silver Carp (Hypophthalmichthys molitrix) GLUT1 under Hypoxia Stress". Fishes 8, n. 8 (20 agosto 2023): 425. http://dx.doi.org/10.3390/fishes8080425.
Abstract (sommario):
As an important freshwater species with economic and ecological benefits, silver carp (Hypophthalmichthys molitrix) exhibits poor tolerance to hypoxia. Glucose transporters (GLUTs) are core membrane proteins that transport glucose to tissues and regulate essential life activities. Its expression is regulated by HIF-1α and cells in hypoxic conditions to maintain energy demand through GLUTs inducing enhanced glucose transport. We cloned H. molitrix glut1 (SLC2A1) and analyzed its sequence using bioinformatics tools. The glut1 cDNA was 2104 base pairs long and encoded a 490 amino acid protein. Phylogenetic analysis revealed that sliver carp glut1 is evolutionarily conserved and exhibited the highest sequence similarity with Ctenopharyngodon idella glut1. Glut1 expression was the highest and lowest in the gills and liver, respectively. Hypoxic stress significantly increased glut1 expression in the brain (p < 0.05); in the gills, it was the highest and lowest in the semi-asphyxia and asphyxia groups, respectively; in the liver, it was significantly higher under hypoxia than that of the normoxia group; and in the heart, it was significantly higher in the floating head, semi-asphyxia, and asphyxia groups than in the normoxia group (p < 0.05). The proposed mechanism may thus provide the basis for elucidating the molecular basis of silver carp’s hypoxia stress response mediated by glut1.
29
Barkat, Ayoub, Foued Bouaicha, Oualid Bouteraa, Tamás Mester, Behnam Ata, Dániel Balla, Zakaria Rahal e György Szabó. "Assessment of Complex Terminal Groundwater Aquifer for Different Use of Oued Souf Valley (Algeria) Using Multivariate Statistical Methods, Geostatistical Modeling, and Water Quality Index". Water 13, n. 11 (7 giugno 2021): 1609. http://dx.doi.org/10.3390/w13111609.
Abstract (sommario):
This research aims to assess the hydrogeochemical evolution of the groundwater in Oued souf valley for drinking and irrigation purposes. To achieve this, 49 groundwater samples from the complex terminal were examined and treated concurrently with multivariate statistical methods, geostatistical modeling and the WQI (water quality index). Focusing on the physico-chemical parameters, Q mode clustering analysis detected four major water groups, where the mineralization augmented from group 1 to group 4. The hydro-chemical type was the same, Ca-Mg-Cl-SO4 for all the groups. Calcite, dolomite, anhydrite, and gypsum would be the dominant reactions with the undersaturation of evaporates minerals, based on geochemical modeling, while the carbonate minerals are precipitating. Geostatistical analysis using ordinary Kriging demonstrated the exponential semi-variogram model fitted for EC (electrical conductivity), Ca2+ (calcium), Mg2+ (magnesium), K+ (potassium), HCO3− (bicarbonate), Cl− (chloride), and SO42− (sulfate). At the same time, the rational quadratic model was the best-fitted semi-variogram model for Na+ (sodium) and NO3− (nitrate). EC, SO42−, and NO3− have a strong spatial structure, while Ca2+, Na+, K+, and HCO3− have a moderate spatial structure. Moreover, there was a weak spatial structure for Mg2+ and Cl−. The WQI shows that CT (complex terminal groundwater aquifers) are not suitable for drinking and their quality for irrigation fluctuates from excellent to moderate quality.
30
Abdulameer, Mohammed Salim. "THE EFFECT OF FEMINISM ON EGYPTIAN LITERATURE". American Journal of Social Science and Education Innovations 06, n. 05 (12 maggio 2024): 74–82. http://dx.doi.org/10.37547/tajssei/volume06issue05-06.
Abstract (sommario):
This study examines the contemporary Egyptian female subculture movements that have brought life to the nation's media landscape. According to the study, women have created unique strategies for encouraging a shared discussion on the significance of social change. Their emphasis on lifestyle issues often reserved for closed-door private discussions enables them to question social norms without upsetting the government or security services and entering the polarised political environment. This article examines the objectives and internal workings of three distinct online feminist initiatives using case studies. Through semi-structured interviews with important participants, we were able to understand the evolution of these groups from networks to movements and ultimately into the organizations we are familiar with today.
31
Koyama, Asuka, Tomoyo F. Koyanagi, Munemitsu Akasaka, Yoshinobu Kusumoto, Syuntaro Hiradate, Masayuki Takada e Kimiko Okabe. "Partitioning the plant diversity of semi-natural grasslands across Japan". Oryx 52, n. 3 (20 febbraio 2017): 471–78. http://dx.doi.org/10.1017/s0030605316001526.
Abstract (sommario):
AbstractEffective conservation of global species diversity requires a clear understanding of spatial scales that support overall diversity across broad scales. Abandonment of semi-natural grasslands has increased their fragmentation and decreased their areal extent. We quantified diversity patterns of plant communities in Japan across hierarchical scales to facilitate the development of an effective nationwide strategy for conserving species diversity in remnant semi-natural grasslands. We applied additive partitioning of plant species diversity, using a nested hierarchical design at three spatial scales (quadrat, grassland, and western and eastern regions of Japan) for three groups of plant species (all species, grassland species and national Red Listed species). We consistently found lower proportions of among-quadrats diversity, and higher proportions of among-grasslands diversity and between-regions diversity in the overall diversity of the entire species complement than would be expected by chance. The high contribution of among-grasslands diversity to overall diversity suggests that each grassland had a unique species content. The second-ranking contributor to overall diversity differed between grassland species and Red Listed species: the second-ranking contributor for grassland species was diversity at the among-quadrats scale but the second-ranking contributor for all species and for Red Listed species was diversity at the between-regions scale. Thus, effective conservation of diversity of the entire species complement in remnant semi-natural grasslands requires preservation of beta diversity in individual grasslands. Our findings highlight the importance of strengthening local preservation and restoration activities within each grassland, and of nationwide strategies for conserving Red Listed species in remnant semi-natural grassland communities.
32
Ding, Yanqiong, Yazhou Xu e Shuhang Ding. "A Stochastic Earthquake Ground Motion Database and Its Application in Seismic Analysis of an RC Frame-Shear Wall Structure". Buildings 13, n. 7 (27 giugno 2023): 1637. http://dx.doi.org/10.3390/buildings13071637.
Abstract (sommario):
A stochastic earthquake ground motion database comprising twelve groups of simulated ground motions was introduced. Ground motions were generated using the stochastic semi-physical model of earthquake ground motions, based on a cluster analysis of 7778 recorded earthquake ground motion. All twelve groups of simulated earthquake ground motions were validated through the probability density evolution method (PDEM) by comparing their time histories and response spectra. As an application of the proposed database, an 18-story reinforced concrete (RC) frame-shear wall structure was analyzed using one group of simulated earthquake ground motions. The probability densities of the top displacement of the structure were estimated using PDEM, highlighting the significant stochasticity of the structural response. The seismic reliability of the structure was assessed by evaluating the extreme value distribution of the story drift angle. The investigations indicate that the proposed stochastic earthquake ground motion database effectively captures the inherent stochasticity of ground motions. Moreover, it contributes to enhancing the efficiency of reliability assessments for structures.
33
Foti, R., e J. A. Ramírez. "A mechanistic description of the formation and evolution of vegetation patterns". Hydrology and Earth System Sciences 17, n. 1 (11 gennaio 2013): 63–84. http://dx.doi.org/10.5194/hess-17-63-2013.
Abstract (sommario):
Abstract. Vegetation patterns are a common and well-defined characteristic of many landscapes. In this paper we explore some of the physical mechanisms responsible for the establishment of self-organized, non-random vegetation patterns that arise at the hillslope scale in many areas of the world, especially in arid and semi-arid regions. In doing so, we provide a fundamental mechanistic understanding of the dynamics of vegetation pattern formation and development. Reciprocal effects of vegetation on the hillslope thermodynamics, runoff production and run-on infiltration, root density, surface albedo and soil moisture content are analyzed. In particular, we: (1) present a physically based mechanistic description of processes leading to vegetation pattern formation; (2) quantify the relative impact of each process on pattern formation; and (3) describe the relationships between vegetation patterns and the climatic, hydraulic and topographic characteristics of the system. We validate the model by comparing simulations with observed natural patterns in the areas of Niger near Niamey and Somalia near Garoowe. Our analyses suggest that the phenomenon of pattern formation is primarily driven by run-on infiltration and mechanisms of facilitation/inhibition among adjacent vegetation groups, mediated by vegetation effects on soil properties and controls on soil moisture and albedo. Nonetheless, even in presence of those mechanisms, patterns arise only when the climatic conditions, particularly annual precipitation and net radiation, are favorable.
34
Foti, R., e J. A. Ramírez. "A mechanistic description of the formation and evolution of vegetation patterns". Hydrology and Earth System Sciences Discussions 9, n. 7 (19 luglio 2012): 8737–98. http://dx.doi.org/10.5194/hessd-9-8737-2012.
Abstract (sommario):
Abstract. Vegetation patterns are a common and well-defined characteristic of many landscapes. In this paper we explore some of the physical mechanisms responsible for the establishment of self-organized, non-random vegetation patterns that arise at the hillslope scale in many areas of the world, especially in arid and semi-arid regions. In doing so, we provide a fundamental mechanistic understanding of the dynamics of vegetation pattern formation and development. Reciprocal effects of vegetation on the hillslope thermodynamics, runoff production and run-on infiltration, root density, surface albedo and soil moisture content are analyzed. In particular, we: (1) present a physically based mechanistic description of processes leading to vegetation pattern formation; (2) quantify the relative impact of each process on pattern formation; and (3) describe the relationships between vegetation patterns and the climatic, hydraulic and topographic characteristics of the system. We validate the model by comparing simulations with observed natural patterns in the areas of Niger near Niamey and Somalia near Garoowe. Our analyses suggest that the phenomenon of pattern formation is primarily driven by run-on infiltration and mechanisms of facilitation/inhibition among adjacent vegetation groups mediated by vegetation effects on soil properties and controls on soil moisture and albedo. Nonetheless, even in presence of those mechanisms, patterns arise only when the climatic conditions, particularly annual precipitation and net radiation, are favorable.
35
Zhang, Tingting, Xin Zhang, Qiuxia Yang e Xinli Wei. "Hidden Species Diversity was Explored in Two Genera of Catapyrenioid Lichens (Verrucariaceae, Ascomycota) from the Deserts of China". Journal of Fungi 8, n. 7 (13 luglio 2022): 729. http://dx.doi.org/10.3390/jof8070729.
Abstract (sommario):
Verrucariaceae is the third-largest lichen family with high species diversity. However, this diversity has not been well-explored in China. We carried out a wide-scale field investigation in the arid and semi-arid regions of Northwest China from 2017 to 2021. A large number of lichen groups, especially those commonly distributed in deserts, were collected. Based on molecular phylogeny using ITS and nuLSU sequences by Bayesian and maximum likelihood analyses, combining morphological characters, seven taxa of catapyrenioid lichens in Verricariaceae were found in this study, including one genus (Clavascidium) and one species (Clavascidium lacinulatum) new to China; one genus (Placidium) new to the mainland of China; and four species (Clavascidium sinense, Placidium nitidulum, Placidium nigrum, and Placidium varium) new to science. It enriched our understanding of the high species diversity in Verrucariaceae and the lichen flora of Chinese arid and semi-arid deserts.
36
Danell, Anna C., Henrik Andrén, Peter Segerström e Robert Franzén. "Space use by Eurasian lynx in relation to reindeer migration". Canadian Journal of Zoology 84, n. 4 (aprile 2006): 546–55. http://dx.doi.org/10.1139/z06-021.
Abstract (sommario):
Semi-domesticated reindeer ( Rangifer tarandus tarandus (L., 1758)) is the primary prey of Eurasian lynx ( Lynx lynx (L., 1758)) in northern Sweden. The reindeer migrate between winter range in the forest and summer range in the mountains, a distance of 100–150 km. We studied space use by Eurasian lynx in relation to seasonal fluctuations of their primary prey in northern Sweden. The seasonal activity range sizes for males and single females were not significantly different between the three periods of the year (December–April, May–July, and August–November). The activity range size for family groups (i.e., female with kittens) was significantly smaller during summer than during autumn and winter. The mean distance between the centre of an individual lynx's activity range in one season to the centre of the activity range in the season immediately following did not differ significantly between seasons; mean distances were 6.6 km for males, 7.3 km for single females, and 8.4 km for family groups. This is about one order of magnitude shorter than the distance between summer and winter ranges for reindeer (100–150 km). The grand mean overlap between a lynx's activity range in one season and the next season was more than 40%. Hence, Eurasian lynx in northern Sweden do not appear to move with the migrating semi-domesticated reindeer.
37
Adams, Jacqueline. "When Art Loses its Sting: The Evolution of Protest Art in Authoritarian Contexts". Sociological Perspectives 48, n. 4 (dicembre 2005): 531–58. http://dx.doi.org/10.1525/sop.2005.48.4.531.
Abstract (sommario):
Change in art is an understudied topic in sociological research. This article examines protest artworks ( arpilleras) produced by shantytown women during and shortly after the dictatorship in Chile, to explore the question why political art that is for sale changes over time. This research is based on 136 semi-structured and in-depth interviews with various members of the art world in Chile, Europe, and the United States, a year's worth of participant observation of art groups in Santiago and over five hundred photographs of arpilleras, taken by the author and analyzed thematically. Political art that is for sale can change because the intermediary (the organization connecting producers and buyers) becomes less or more politically conservative, develops a precarious financial situation, grows more afraid of repression, and has the power to enforce the changes it desires; because the original buyers are replaced with new buyers with different motivations; and because new artists with new ideas begin making the art, one artist in the group produces something different and the idea spreads, artists censor themselves, and artists have new experiences or learn about new events. Through these sources of change, international social movements, local and international political and economic developments, and global institutions impact the art. Meanings attached to the art by the different parties (intermediaries, buyers, and artists) and class differences between artists and intermediaries are also important in facilitating change. These findings, based as they are on political art made in a repressive context, not only contribute to our understanding of artistic evolution but they help correct the bias in the sociology of art toward “art” made in democratic countries of the “First World.” They are not just applicable to authoritarian regimes but also to art by politicized minority groups in democratic contexts, and to other cultural products such as newspapers, magazines, documentaries, and books.
38
Yurchenko, Eugene O. "Natural substrata for corticioid fungi". Acta Mycologica 41, n. 1 (23 dicembre 2013): 113–24. http://dx.doi.org/10.5586/am.2006.015.
Abstract (sommario):
The paper reviews the types of substrata inhabited by non-poroid resupinate Homobasidiomycetes <em>in situ</em> in global scale with both examples from literature sources and from observations on Belarus corticioid fungi biota. The groups of organic world colonized by corticioid basidiomata and vegetative mycelium are arboreous, semi-arboreous, and herbaceous vascular plants, Bryophyta, epiphytic coccoid algae, lichenized and non-lichenized fungi, and occasionally myxomycetes and invertebrates. The fungi occur on living, dying, and dead on all decay stages parts of organisms. Besides, the fungi are known on soil, humus, stones, artificial inorganic and synthetic materials and dung.
39
ARRUDA, DANIEL M., WALNIR G. FERREIRA-JUNIOR, REINALDO DUQUE-BRASIL e CARLOS E. R. SCHAEFER. "Phytogeographical patterns of dry forests sensu stricto in northern Minas Gerais State, Brazil". Anais da Academia Brasileira de Ciências 85, n. 2 (giugno 2013): 623–34. http://dx.doi.org/10.1590/s0001-37652013000200011.
Abstract (sommario):
The Deciduous Complex that occurs in northern Minas Gerais State, Brazil, raises questions about the floristic affinities of these formations in relation to neighboring phytogeographical domains. Little is known about the identity of the seasonal forest formations that comprise this complex, or about its relationships to abiotic components, such as soils, topography and climate. This study aimed to recognize the patterns of floristic similarity of all studied fragments of dry forest of northern Minas Gerais with soil and climate attributes, based on the available database. Cluster analysis indicated the existence of two floristic groups that had clear associations with either the Koppen's BSh (semi-arid) or Aw (seasonal tropical) climates. Likewise, the subdivisions of these groups showed clear associations with the dominant soil classes in the region. The Red-Yellow Latosol is the dominant soil classes in the BSh climatic domain, seconded by alluvial areas associated with Fluvic Neosols. The Aw domain comprised a much varied set of soils: Nitosols, Argisols, Cambisols and Litholic Neosols, most derived from the Bambuí limestone/slate formation. The ecotonal nature of northern Minas Gerais State provides a complex interaction between the flora of neighboring phytogeographical domains. This, allied to pedogeomorphological factors, allowed a better understanding of the effects of late Quaternary climate changes for the Deciduous Complex evolution. We conclude that the Latosols under present-day semi-arid climates (BSh) are relicts of former wetter climates, during which humid forest (semideciduous) expansion took place. Later, these semideciduous forests were subjected to a much drier climate, when selection for deciduousness led to the present-days Deciduous Complex scenario.
40
Holzinger, R., A. H. Goldstein, P. L. Hayes, J. L. Jimenez e J. Timkovsky. "Chemical evolution of organic aerosol in Los Angeles during the CalNex 2010 study". Atmospheric Chemistry and Physics Discussions 13, n. 5 (15 maggio 2013): 12867–911. http://dx.doi.org/10.5194/acpd-13-12867-2013.
Abstract (sommario):
Abstract. During the CalNex study (15 May to 16 June 2010) a large suite of instruments was operated at the Los Angeles area ground supersite to characterize the sources and atmospheric processing of atmospheric pollution. The thermal-desorption proton-transfer-reaction mass-spectrometer (TD-PTR-MS) was deployed to an urban area for the first time and detected 691 organic ions in aerosol samples, the mean total concentration of which was estimated as 3.3 μg m−3. Based on comparison to total organic aerosol (OA) measurements, we estimate that approximately 50% of the OA mass at this site was directly measured by the TD-PTR-MS. Based on correlations with aerosol mass spectrometer (AMS) OA components, the ions were grouped to represent hydrocarbon-like OA (HOA), local OA (LOA), semi-volatile oxygenated OA (SV-OOA), and low volatility oxygenated OA (LV-OOA). Mass spectra and thermograms of the ion groups are mostly consistent with the assumed sources and/or photochemical origin of the OA components. The mass spectra of ions representing the primary components HOA and LOA included the highest m/z, consistent with their higher resistance to thermal decomposition, and they were volatilized at lower temperatures. Photochemical ageing weakens C-C bond strengths (also resulting in chemical fragmentation), and produces species of lower volatility (through the addition of functional groups). Accordingly the mass spectra of ions representing the oxidized OA components (SV-OOA, and LV-OOA) lack the highest masses and they are volatilized at higher temperatures. Chemical parameters like mean carbon number (nC), mean carbon oxidation state (OSC), and the atomic ratios O/C and H/C of the ion groups are consistent with the expected sources and photochemical processing of the aerosol components. Our data suggest that chemical fragmentation gains importance over functionalization as photochemical age of OA increases. Surprisingly, the photochemical age of OA decreases during the daytime hours, demonstrating the importance of rapid production of new (photochemically young) SV-OOA during daytime. The PTR detects higher organic N concentrations than the AMS, the reasons for which are not well understood and cannot be explained by known artifacts related to PTR or the AMS. The median atomic N/C ratio (6.4%) of the ion group representing LV-OOA is a factor 2 higher than N/C of any other ion group. This suggests a multiphase chemical source involving ammonium ions is contributing to LV-OOA.
41
Holzinger, R., A. H. Goldstein, P. L. Hayes, J. L. Jimenez e J. Timkovsky. "Chemical evolution of organic aerosol in Los Angeles during the CalNex 2010 study". Atmospheric Chemistry and Physics 13, n. 19 (15 ottobre 2013): 10125–41. http://dx.doi.org/10.5194/acp-13-10125-2013.
Abstract (sommario):
Abstract. During the CalNex study (15 May to 16 June 2010) a large suite of instruments was operated at the Los Angeles area ground supersite to characterize the sources and atmospheric processing of atmospheric pollution. The thermal-desorption proton-transfer-reaction mass-spectrometer (TD-PTR-MS) was deployed to an urban area for the first time and detected 691 organic ions in aerosol samples, the mean total concentration of which was estimated as 3.3 μg m−3. Based on comparison to total organic aerosol (OA) measurements, we estimate that approximately 50% of the OA mass at this site was directly measured by the TD-PTR-MS. Based on correlations with aerosol mass spectrometer (AMS) OA components, the ions were grouped to represent hydrocarbon-like OA (HOA), local OA (LOA), semi-volatile oxygenated OA (SV-OOA), and low volatility oxygenated OA (LV-OOA). Mass spectra and thermograms of the ion groups are mostly consistent with the assumed sources and/or photochemical origin of the OA components. The mass spectra of ions representing the primary components HOA and LOA included the highest m/z, consistent with their higher resistance to thermal decomposition, and they were volatilized at lower temperatures (~ 150 °C). Photochemical ageing weakens C-C bond strengths (also resulting in chemical fragmentation), and produces species of lower volatility (through the addition of functional groups). Accordingly the mass spectra of ions representing the oxidized OA components (SV-OOA, and LV-OOA) lack the highest masses and they are volatilized at higher temperatures (250–300 °C). Chemical parameters like mean carbon number (nC), mean carbon oxidation state (OSC), and the atomic ratios O / C and H / C of the ion groups are consistent with the expected sources and photochemical processing of the aerosol components. Our data suggest that chemical fragmentation gains importance over functionalization as photochemical age of OA increases. Surprisingly, the photochemical age of OA decreases during the daytime hours, demonstrating the importance of rapid production of new (photochemically young) SV-OOA during daytime. The PTR detects higher organic N concentrations than the AMS, the reasons for which are not well understood and cannot be explained by known artifacts related to PTR or the AMS. The median atomic N / C ratio (6.4%) of the ion group representing LV-OOA is a factor 2 higher than N / C of any other ion group. This suggests a multiphase chemical source involving ammonium ions is contributing to LV-OOA.
42
MD, Santhi, Anuratha MD e Kokilavani. "Effectiveness of Semi Sitting Position during 2nd Stage of Labour on Maternal and Neonatal Outcomes among Primigravida". Nursing Journal of India CIII, n. 06 (2012): 272–75. http://dx.doi.org/10.48029/nji.2012.ciii606.
Abstract (sommario):
This post-test experimental study was conducted among 50 primigravida mothers - 25 each in experimental and control groups in a maternity centre of Coimbatore (TN) with a view to assess the effect of semi-sitting position during second stage of labour on maternal and neonatal outcomes. It was found that semi sitting position is beneficial in enhancing thrust and directing the uterine contraction force on foetus that lead to fewer late decelerations and increased APGAR score.
43
Arnaiz-Villena, Antonio, José Palacio-Gruber, Valentín Ruiz-del-Valle, Alba Heras-Garcia, Marta Molina-Alejandre e Fabio Suarez-Trujillo. "The Iberian-Tartessian semi-syllabary: possible evolution from Lineal Megalithic/Paleolithic Scripts and the Mother Goddess Religion". International Journal of Modern Anthropology 2, n. 17 (5 giugno 2022): 820–41. http://dx.doi.org/10.4314/ijma.v2i17.6.
Abstract (sommario):
Paleolithic/Neolithic (Megalithic) Lineal Scripts have been found in big or small rocks with or without megalithic context. Huelva (South West Spain) megalithic rocks presented engraved signs apparently contained in the Iberian-Tartessian semi-syllabary and this region is in the core of Tartessian civilization. Iberian-Tartessian scripts have been found in South West Algeria, Canary Islands and Iberia. The genesis of this type of writing may have more ancient roots than established (1st Century BC) as Strabo stated that it may be thousands of years older. The finding of the same Iberian-Tartessian signs within such a big geographic area supports that demic diffusion substitution either from East Mediterranean or Russian steppes is not found in Iberia according to physical anthropology traits and also genetic studies from different research groups from different countries: Iberians, North Africans and Canary Islanders are genetically close supporting prehistorical contacts also sustained by Sahara Desert rapid desiccation followed by people migration. On the other hand, it is difficult to understand Paleolithic /Neolithic-Megalithic Lineal rock inscriptions continuity in such a long period without a known language, considered identical or related to Iberian, or political unit unless Basque language, or similar one, was present in Paleolithic time, as suggested by some authors. Paleolithic Lineal scripts have also been found in Java (Indonesia) and South Africa. It is feasible that worldwide Mother Goddess religion which extended since Paleolithic to Neolithic/Megalithic times may be the one common certain and documented character available to blame of such a surprising unity and continuity of rock lineal engravings.
44
Friend, GR, GT Smith, DS Mitchell e CR Dickman. "Influence of Pitfall and Drift Fence Design on Capture Rates of Small Vertebrates in Semi-Arid Habitats of Western-Australia". Wildlife Research 16, n. 1 (1989): 1. http://dx.doi.org/10.1071/wr9890001.
Abstract (sommario):
The influence of several attributes of pitfall and drift fence design on capture rates of small vertebrates was examined over 12 months in semi-arid habitats of Western Australia. Large 28 cm diameter pits (20 L buckets), captured significantly more animals than smaller pits made of 16 cm diameter PVC piping. Amongst taxonomic groups, large lizards and geckos showed highly significant biases for large pits, frogs, small lizards, and snakes and legless lizards less so, while small mammals were caught equally often in both sizes. All faunal groups except geckos showed an overall significant increase in capture rates with increasing fence length, but the optimal length per pit cannot be accurately determined from our data. Faunal groups showed a dichotomy in responses to temporary verus permanent drift fences. Independent fenced pits produced significantly higher capture rates than those in a conventional driftline. Variations in species responses to different design attributes probably reflect differing modes of behaviour and activity. We conclude that for our study areas, many large pits installed as a grid at 10-20 m spacing, each with a permanently erected short drift fence (e.g. 7-10 m), should produce excellent results for both autecological and synecological studies.
45
Cassiani, Massimo, Matteo B. Bertagni, Massimo Marro e Pietro Salizzoni. "Concentration Fluctuations from Localized Atmospheric Releases". Boundary-Layer Meteorology 177, n. 2-3 (4 agosto 2020): 461–510. http://dx.doi.org/10.1007/s10546-020-00547-4.
Abstract (sommario):
Abstract We review the efforts made by the scientific community in more than seventy years to elucidate the behaviour of concentration fluctuations arising from localized atmospheric releases of dynamically passive and non-reactive scalars. Concentration fluctuations are relevant in many fields including the evaluation of toxicity, flammability, and odour nuisance. Characterizing concentration fluctuations requires not just the mean concentration but also at least the variance of the concentration in the location of interest. However, for most purposes the characterization of the concentration fluctuations requires knowledge of the concentration probability density function (PDF) in the point of interest and even the time evolution of the concentration. We firstly review the experimental works made both in the field and in the laboratory, and cover both point sources and line sources. Regarding modelling approaches, we cover analytical, semi-analytical, and numerical methods. For clarity of presentation we subdivide the models in two groups, models linked to a transport equation, which usually require a numerical resolution, and models mainly based on phenomenological aspects of dispersion, often providing analytical or semi-analytical relations. The former group includes: large-eddy simulations, Reynolds-averaged Navier–Stokes methods, two-particle Lagrangian stochastic models, PDF transport equation methods, and heuristic Lagrangian single-particle methods. The latter group includes: fluctuating plume models, semi-empirical models for the concentration moments, analytical models for the concentration PDF, and concentration time-series models. We close the review with a brief discussion highlighting possible useful additions to experiments and improvements to models.
46
Majeed, Muhammad, Khizar Hayat Bhatti, Andrea Pieroni, Renata Sõukand, Rainer W. Bussmann, Arshad Mahmood Khan, Sunbal Khalil Chaudhari, Muhammad Abdul Aziz e Muhammad Shoaib Amjad. "Gathered Wild Food Plants among Diverse Religious Groups in Jhelum District, Punjab, Pakistan". Foods 10, n. 3 (11 marzo 2021): 594. http://dx.doi.org/10.3390/foods10030594.
Abstract (sommario):
Recent ethnobotanical studies have raised the hypothesis that religious affiliation can, in certain circumstances, influence the evolution of the use of wild food plants, given that it shapes kinship relations and vertical transmission of traditional/local environmental knowledge. The local population living in Jhelum District, Punjab, Pakistan comprises very diverse religious and linguistic groups. A field study about the uses of wild food plants was conducted in the district. This field survey included 120 semi-structured interviews in 27 villages, focusing on six religious groups (Sunni and Shia Muslims, Christians, Hindus, Sikhs, and Ahmadis). We documented a total of 77 wild food plants and one mushroom species which were used by the local population mainly as cooked vegetables and raw snacks. The cross-religious comparison among six groups showed a high homogeneity of use among two Muslim groups (Shias and Sunnis), while the other four religious groups showed less extensive, yet diverse uses, staying within the variety of taxa used by Islamic groups. No specific plant cultural markers (i.e., plants gathered only by one community) could be identified, although there were a limited number of group-specific uses of the shared plants. Moreover, the field study showed erosion of the knowledge among the non-Muslim groups, which were more engaged in urban occupations and possibly underwent stronger cultural adaption to a modern lifestyle. The recorded traditional knowledge could be used to guide future development programs aimed at fostering food security and the valorization of the local bio-cultural heritage.
47
Kretschmer, Rafael, Benilson Silva Rodrigues, Suziane Alves Barcellos, Alice Lemos Costa, Marcelo de Bello Cioffi, Analía del Valle Garnero, Ricardo José Gunski, Edivaldo Herculano Corrêa de Oliveira e Darren K. Griffin. "Karyotype Evolution and Genomic Organization of Repetitive DNAs in the Saffron Finch, Sicalis flaveola (Passeriformes, Aves)". Animals 11, n. 5 (19 maggio 2021): 1456. http://dx.doi.org/10.3390/ani11051456.
Abstract (sommario):
The Saffron finch (Sicalis flaveola), a semi-domestic species, is tolerant of human proximity and nesting in roof spaces. Considering the importance of cytogenomic approaches in revealing different aspects of genomic organization and evolution, we provide detailed cytogenetic data for S. flaveola, including the standard Giemsa karyotype, C- and G-banding, repetitive DNA mapping, and bacterial artificial chromosome (BAC) FISH. We also compared our results with the sister groups, Passeriformes and Psittaciformes, bringing new insights into the chromosome and genome evolution of birds. The results revealed contrasting rates of intrachromosomal changes, highlighting the role of SSR (simple short repetition probes) accumulation in the karyotype reorganization. The SSRs showed scattered hybridization, but brighter signals were observed in the microchromosomes and the short arms of Z chromosome in S. flaveola. BACs probes showed conservation of ancestral syntenies of macrochromosomes (except GGA1), as well as the tested microchromosomes. The comparison of our results with previous studies indicates that the great biological diversity observed in Passeriformes was not likely accompanied by interchromosomal changes. In addition, although repetitive sequences often act as hotspots of genome rearrangements, Passeriformes species showed a higher number of signals when compared with the sister group Psittaciformes, indicating that these sequences were not involved in the extensive karyotype reorganization seen in the latter.
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Anuard, Pacheco-Guerrero, González-Trinidad Julián, Júnez-Ferreira Hugo, Bautista-Capetillo Carlos, Hernández-Antonio Arturo, Olmos-Trujillo Edith e Ávila-Sandoval Claudia. "Integration of Isotopic (2H and 18O) and Geophysical Applications to Define a Groundwater Conceptual Model in Semiarid Regions". Water 11, n. 3 (8 marzo 2019): 488. http://dx.doi.org/10.3390/w11030488.
Abstract (sommario):
One-third of the global population depends on groundwater for drinking, which is an even larger proportion for arid regions. The integration of isotopic and geophysical applications has been very useful in understanding the process of groundwater recharge. The aim of this study is to define a conceptual model that describes groundwater functions within an aquifer located in a semi-arid region by identifying recharge patterns based on the isotopic characteristics of: Rainfall, surface water, shallow and deep groundwater, and incorporating regional geophysical data. We demonstrated that rainfall was affected by sub-cloud evaporation and altitude. Shallow and deep modern groundwater samples were clustered and exhibited similar evolution from rainfall. However, different groups recharged from different precipitation sources compared to the local one. In the current study, we analyzed the isotopic evolution of deep groundwater over a 10-year period, which was mainly affected by the incorporation of different flows with different isotopic signatures and the hydrodynamics of the area. We performed two geoelectrical sections in the study area to improve the understanding of the hydrogeological setting and water movement patterns. The new conceptual model should help stakeholders in the context of water management policies for the study area.
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Bagi, Hoseeinali, Asghar Atesampour e Ali Rahimi. "Environmental significance of benthic foraminifera and microfacies of central Tethyan Upper Triassic strata, central Iran". Stratigraphy 18, n. 2 (15 giugno 2021): 89–102. http://dx.doi.org/10.29041/strat.18.2.01.
Abstract (sommario):
ABSTRACT: The evolution of the Late TriassicNaybandBasin in central Iranwas influenced by climatic changes and tectonic events. An increase in siliciclastic input and a corresponding carbonate productivity crisis in theQhrogchi area in central Iranwere initiated by the onset of a relatively humid episode in the Carnian, followed by arid to semi-arid conditions in the Norian and Rhaetian. Carbonate sediments of theNayband Formationwere deposited in a range of environments, from outer ramp to marginal marine environments. The rich benthic fauna is predominantly restricted to the limestone bedswithin the upper part of succession. Bivalves, hydrozoans (Heterastridium), calcareous algae, corals and sclerosponges are recorded. The latter two groups form patch reefs on the middle ramp. Benthic foraminifera show strong affinities with assemblages reported from the central Tethys, whereas others are also well-known from the Alpine region and from the eastern Tethys.
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Petters, M. D., S. M. Kreidenweis e P. J. Ziemann. "Prediction of cloud condensation nuclei activity for organic compounds using functional group contribution methods". Geoscientific Model Development Discussions 8, n. 9 (1 settembre 2015): 7445–75. http://dx.doi.org/10.5194/gmdd-8-7445-2015.
Abstract (sommario):
Abstract. A wealth of recent laboratory and field experiments demonstrate that organic aerosol composition evolves with time in the atmosphere, leading to changes in the influence of the organic fraction to cloud condensation nuclei (CCN) spectra. There is a need for tools that can realistically represent the evolution of CCN activity to better predict indirect effects of organic aerosol on clouds and climate. This work describes a model to predict the CCN activity of organic compounds from functional group composition. The model combines Köhler theory with semi-empirical group contribution methods to estimate molar volumes, activity coefficients and liquid-liquid phase boundaries to predict the effective hygroscopicity parameter, kappa. Model evaluation against a selected database of published laboratory measurements demonstrates that kappa can be predicted within a factor of two. Simulation of homologous series is used to identify the relative effectiveness of different functional groups in increasing the CCN activity of weakly functionalized organic compounds. Hydroxyl, carboxyl, aldehyde, hydroperoxide, carbonyl, and ether moieties promote CCN activity while methylene and nitrate moieties inhibit CCN activity. The model can be incorporated into scale-bridging testbeds such as the Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere to evaluate the evolution of kappa for a complex mix of organic compounds and to develop suitable parameterizations of CCN evolution for larger scale models.