859 resultados para Visão de cores. Reprodução. Comunicação socio-sexual. Primatas do Novo Mundo. Callithrix jacchus


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Väitöskirjatutkimuksen tavoitteena oli selvittää, miten aviopuolisoiden sosioekonominen asema vaikuttaa avioeroriskiin Suomessa. Tutkimuksessa käytettiin Tilastokeskuksen rekistereistä koottua aineistoa, joka koskee suomalaisten ensimmäisiä avioliittoja vuoden 1990 lopussa ja avioeroja vuosina 1991−93. Väitöskirjaan sisältyy kolme osatutkimusta. Ensimmäinen osatutkimus käsitteli avioeroriskin vaihtelua aviopuolisoiden sosioekonomisen aseman eri osatekijöiden (koulutusaste, sosiaaliryhmä, pääasiallinen toiminta, tulotaso, asunnon omistaminen ja asumisahtaus) mukaan. Kaiken kaikkiaan avioeroriski oli sitä pienempi, mitä paremmassa taloudellisessa ja sosiaalisessa asemassa aviopuolisot olivat. Esimerkiksi miehen ja vaimon korkea koulutusaste, toimihenkilöammatti, työssäkäynti (etenkin verrattuna työttömyyteen) sekä omistusasunnossa asuminen liittyivät pienentyneeseen avioeroriskiin. Vaimon sosioekonomisen aseman yhteys avioeroriskiin oli paljolti samanlainen kuin miehen aseman yhteys. Huomattavin poikkeus tähän oli, että vaimon suuret tulot lisäsivät avioeroriskiä, vaikka miehen suurilla tuloilla oli päinvastainen vaikutus. Lisäksi kotitaloustyötä pääasiallisena toimintanaan tekevillä naisilla (pääasiallisen toiminnan luokka ”muut”) oli vielä pienempi avioeroriski kuin työssäkäyvillä naisilla. Toisessa osatutkimuksessa keskityttiin aviomiehen ja vaimon aseman yhdistettyyn vaikutukseen. Selviä viitteitä siitä, että puolisoiden koulutustasojen erilaisuus lisäisi eroriskiä, ei saatu. Pareilla, joissa molemmilla oli enintään perusasteen koulutus, oli kuitenkin odotettua pienempi avioeroriski. Eroriski oli suhteellisen alhainen pareilla, joissa vaimo oli työssäkäyvä tai kotitaloustyötä tekevä ja aviomies työssäkäyvä. Eroriskiä kasvatti se, että aviomies, vaimo tai molemmat puolisot olivat työttömiä. Vaimon korkea tulotaso lisäsi eroriskiä miehen kaikilla tulotasoilla mutta erityisen voimakkaasti silloin, kun miehen tulotaso oli alhainen. Kolmanneksi selvitettiin, vaikuttaako puolisoiden sosioekonominen asema avioeroriskiin eri tavalla riippuen siitä, kauanko avioliitto on kestänyt. Tällöin havaittiin, että vähän koulutettujen ja työntekijäammateissa toimivien puolisoiden suuri eroriski rajoittuu paljolti nuorimpiin avioliittoihin. Sen sijaan esim. puolisoiden työttömyys, vaimon korkea tulotaso ja vuokra-asunnossa asuminen kasvattivat eroriskiä riippumatta siitä, kuinka kauan avioliitto oli kestänyt. Kaiken kaikkiaan eroriski oli siis sitä pienempi, mitä paremmassa taloudellisessa ja sosiaalisessa asemassa puolisot olivat. Vaimon taloudellisilla ja sosiaalisilla resursseilla näyttää kuitenkin olevan myös joitakin avioeroriskiä lisääviä vaikutuksia.

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Child sexual abuse is a major global public health concern, affecting one in eight children and causing massive costs including depression, unwanted pregnancy and HIV. The gravity of this global issue is reflected by the United Nations’ new effort to respond to sexual abuse in the 2015 Sustainable Development Goals. The fundamental policy aims are to improve prevention, identification and optimal responses to sexual abuse. However, as shown in our literature review, policymakers face difficult challenges because child sexual abuse is hidden, psychologically complex, and socially sensitive. This article contributes significant new ideas for international progress. Insights about required strategies are informed by an innovative multidisciplinary analysis of research from public health, medicine, social science, psychology, and neurology. Using an ecological model comprising individual, institutional and societal dimensions, we propose that two preconditions for progress are the enhancement of awareness of child sexual abuse, and of empathic responses towards its victims.

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In 2015, Victoria passed laws removing the time limit in which a survivor of child sexual abuse can commence a civil claim for personal injury. The law applies also to physical abuse, and to psychological injury arising from those forms of abuse. In 2016, New South Wales made almost identical legal reforms. These reforms were partly motivated by the recommendations of inquiries into institutional child abuse. Of particular relevance is that the Australian Royal Commission Into Institutional Responses to Child Sexual Abuse recommended in 2015 that all States and Territories remove their time limits for civil claims. This presentation explores the problems with standard time limits when applied to child sexual abuse cases (whether occurring within or beyond institutions), the scientific, ethical and legal justifications for lifting the time limits, and solutions for future law reform.

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Physical properties provide valuable information about the nature and behavior of rocks and minerals. The changes in rock physical properties generate petrophysical contrasts between various lithologies, for example, between shocked and unshocked rocks in meteorite impact structures or between various lithologies in the crust. These contrasts may cause distinct geophysical anomalies, which are often diagnostic to their primary cause (impact, tectonism, etc). This information is vital to understand the fundamental Earth processes, such as impact cratering and associated crustal deformations. However, most of the present day knowledge of changes in rock physical properties is limited due to a lack of petrophysical data of subsurface samples, especially for meteorite impact structures, since they are often buried under post-impact lithologies or eroded. In order to explore the uppermost crust, deep drillings are required. This dissertation is based on the deep drill core data from three impact structures: (i) the Bosumtwi impact structure (diameter 10.5 km, 1.07 Ma age; Ghana), (ii) the Chesapeake Bay impact structure (85 km, 35 Ma; Virginia, U.S.A.), and (iii) the Chicxulub impact structure (180 km, 65 Ma; Mexico). These drill cores have yielded all basic lithologies associated with impact craters such as post-impact lithologies, impact rocks including suevites and breccias, as well as fractured and unfractured target rocks. The fourth study case of this dissertation deals with the data of the Paleoproterozoic Outokumpu area (Finland), as a non-impact crustal case, where a deep drilling through an economically important ophiolite complex was carried out. The focus in all four cases was to combine results of basic petrophysical studies of relevant rocks of these crustal structures in order to identify and characterize various lithologies by their physical properties and, in this way, to provide new input data for geophysical modellings. Furthermore, the rock magnetic and paleomagnetic properties of three impact structures, combined with basic petrophysics, were used to acquire insight into the impact generated changes in rocks and their magnetic minerals, in order to better understand the influence of impact. The obtained petrophysical data outline the various lithologies and divide rocks into four domains. Based on target lithology the physical properties of the unshocked target rocks are controlled by mineral composition or fabric, particularly porosity in sedimentary rocks, while sediments result from diverse sedimentation and diagenesis processes. The impact rocks, such as breccias and suevites, strongly reflect the impact formation mechanism and are distinguishable from the other lithologies by their density, porosity and magnetic properties. The numerous shock features resulting from melting, brecciation and fracturing of the target rocks, can be seen in the changes of physical properties. These features include an increase in porosity and subsequent decrease in density in impact derived units, either an increase or a decrease in magnetic properties (depending on a specific case), as well as large heterogeneity in physical properties. In few cases a slight gradual downward decrease in porosity, as a shock-induced fracturing, was observed. Coupled with rock magnetic studies, the impact generated changes in magnetic fraction the shock-induced magnetic grain size reduction, hydrothermal- or melting-related magnetic mineral alteration, shock demagnetization and shock- or temperature-related remagnetization can be seen. The Outokumpu drill core shows varying velocities throughout the drill core depending on the microcracking and sample conditions. This is similar to observations by Kern et al., (2009), who also reported the velocity dependence on anisotropy. The physical properties are also used to explain the distinct crustal reflectors as observed in seismic reflection studies in the Outokumpu area. According to the seismic velocity data, the interfaces between the diopside-tremolite skarn layer and either serpentinite, mica schist or black schist are causing the strong seismic reflectivities.

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Wetlands are the most productive ecosystems, recognized globally for its vital role in sustaining a wide array of biodiversity and provide goods and services. However despite their important role in maintaining the ecology and economy, wetlands in India are endangered by inattention and lack of appreciation for their role. Increased anthropogenic activities such as intense agriculture practices, indiscriminate disposal of industrial effluents and sewage wastes have altered the physical, chemical as well as biological integrity of the ecosystem. This has resulted in the ecological degradation, which is evident from the current ecosystem valuation of Varthur wetland. Global valuation of coastal wetland ecosystem shows a total of 14,785/ha US$ annual economic value. An earlier study of relatively pristine wetland in Bangalore shows the value of Rs. 10,435/ha/day while the polluted wetland shows the value of Rs.20/ha/day. In contrast to this, Varthur, a sewage fed wetland has a value of Rs.118.9/ha/day. The pollutants and subsequent contamination of the wetland has telling effects such as disappearance of native species, dominance of invasive exotic species (such as African catfish), in addition to profuse breeding of disease vectors and pathogens. Water quality analysis revealed of high phosphates (4.22-5.76 ppm) level in addition to the enhanced BOD (119-140 ppm) and decreased DO (0-1.06 ppm). The amplified decline of ecosystem goods and services with degradation of water quality necessitates the implementation of sustainable management strategies to recover the lost wetland benefits.

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Wetlands are the most productive ecosystems, recognized globally for its vital role in sustaining a wide array of biodiversity and provide goods and services. However despite their important role in maintaining the ecology and economy, wetlands in India are endangered by inattention and lack of appreciation for their role. Increased anthropogenic activities such as intense agriculture practices, indiscriminate disposal of industrial effluents and sewage wastes have altered the physical, chemical as well as biological integrity of the ecosystem. This has resulted in the ecological degradation, which is evident from the current ecosystem valuation of Varthur wetland. Global valuation of coastal wetland ecosystem shows a total of 14,785/ha US$ annual economic value. An earlier study of relatively pristine wetland in Bangalore shows the value of Rs. 10,435/ha/day while the polluted wetland shows the value of Rs.20/ha/day. In contrast to this, Varthur, a sewage fed wetland has a value of Rs.118.9/ha/day. The pollutants and subsequent contamination of the wetland has telling effects such as disappearance of native species, dominance of invasive exotic species (such as African catfish), in addition to profuse breeding of disease vectors and pathogens. Water quality analysis revealed of high phosphates (4.22-5.76 ppm) level in addition to the enhanced BOD (119-140 ppm) and decreased DO (0-1.06 ppm). The amplified decline of ecosystem goods and services with degradation of water quality necessitates the implementation of sustainable management strategies to recover the lost wetland benefits.

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The spectral index-luminosity relationship for steep-spectrum cores in galaxies and quasars has been investigated, and it is found that the sample of galaxies supports earlier suggestions of a strong correlation, while there is weak evidence for a similar relationship for the quasars. It is shown that a strong spectral index-luminosity correlation can be used to set an upper limit to the velocities of the radio-emitting material which is expelled from the nucleus in the form of collimated beams or jets having relativistic bulk velocities. The data on cores in galaxies indicate that the Lorentz factors of the radiating material are less than about 2.

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Multiwavelength data indicate that the X-ray-emitting plasma in the cores of galaxy clusters is not cooling catastrophically. To a large extent, cooling is offset by heating due to active galactic nuclei (AGNs) via jets. The cool-core clusters, with cooler/denser plasmas, show multiphase gas and signs of some cooling in their cores. These observations suggest that the cool core is locally thermally unstable while maintaining global thermal equilibrium. Using high-resolution, three-dimensional simulations we study the formation of multiphase gas in cluster cores heated by collimated bipolar AGN jets. Our key conclusion is that spatially extended multiphase filaments form only when the instantaneous ratio of the thermal instability and free-fall timescales (t(TI)/t(ff)) falls below a critical threshold of approximate to 10. When this happens, dense cold gas decouples from the hot intracluster medium (ICM) phase and generates inhomogeneous and spatially extended Ha filaments. These cold gas clumps and filaments ``rain'' down onto the central regions of the core, forming a cold rotating torus and in part feeding the supermassive black hole. Consequently, the self-regulated feedback enhances AGN heating and the core returns to a higher entropy level with t(TI)/t(ff) > 10. Eventually, the core reaches quasi-stable global thermal equilibrium, and cold filaments condense out of the hot ICM whenever t(TI)/t(ff) less than or similar to 10. This occurs despite the fact that the energy from AGN jets is supplied to the core in a highly anisotropic fashion. The effective spatial redistribution of heat is enabled in part by the turbulent motions in the wake of freely falling cold filaments. Increased AGN activity can locally reverse the cold gas flow, launching cold filamentary gas away from the cluster center. Our criterion for the condensation of spatially extended cold gas is in agreement with observations and previous idealized simulations.

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Chemical signaling is a prominent mode of male-female communication among elephants, especially during their sexually active periods. Studies on the Asian elephant in zoos have shown the significance of a urinary pheromone (Z7-12:Ac) in conveying the reproductive status of a female toward the opposite sex. We investigated the additional possibility of an inter-sexual chemical signal being conveyed through dung. Sixteen semi-captive adult male elephants were presented with dung samples of three female elephants in different reproductive phases. Each male was tested in 3 separate trials, within an interval of 1-3 days. The trials followed a double-blind pattern as the male and female elephants used in the trials were strangers, and the observer was not aware of the reproductive status of females during the period of bioassays. Males responded preferentially (P < 0.005), in terms of higher frequency of sniff, check and place behavior toward the dung of females close to pre-ovulatory period (follicular-phase) as compared to those in post-ovulatory period (luteal-phase). The response toward the follicular phase samples declined over repeated trials though was still significantly higher than the corresponding response toward the non-ovulatory phase in each of the trials performed. This is the first study to show that male Asian elephants were able to distinguish the reproductive phase of the female by possibly detecting a pre-ovulatory pheromone released in dung. (C) 2012 Elsevier B.V. All rights reserved.

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Active galactic nucleus (AGN) jets carry more than sufficient energy to stave off catastrophic cooling of the intracluster medium (ICM) in the cores of cool-core clusters. However, in order to prevent catastrophic cooling, the ICM must be heated in a near-isotropic fashion and narrow bipolar jets with P-jet = 10(44-45) erg s(-1), typical of radio AGNs at cluster centers, are inefficient in heating the gas in the transverse direction to the jets. We argue that due to existent conditions in cluster cores, the supermassive black holes (SMBHs) will, in addition to accreting gas via radiatively inefficient flows, experience short stochastic episodes of enhanced accretion via thin disks. In general, the orientation of these accretion disks will be misaligned with the spin axis of the black holes (BHs) and the ensuing torques will cause the BH's spin axis (and therefore the jet axis) to slew and rapidly change direction. This model not only explains recent observations showing successive generations of jet-lobes-bubbles in individual cool-core clusters that are offset from each other in the angular direction with respect to the cluster center, but also shows that AGN jets can heat the cluster core nearly isotropically on the gas cooling timescale. Our model does require that the SMBHs at the centers of cool-core clusters be spinning relatively slowly. Torques from individual misaligned disks are ineffective at tilting rapidly spinning BHs by more than a few degrees. Additionally, since SMBHs that host thin accretion disks will manifest as quasars, we predict that roughly 1-2 rich clusters within z < 0.5 should have quasars at their centers.

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We examine the role of thermal conduction and magnetic fields in cores of galaxy clusters through global simulations of the intracluster medium (ICM). In particular, we study the influence of thermal conduction, both isotropic and anisotropic, on the condensation of multiphase gas in cluster cores. Previous hydrodynamic simulations have shown that cold gas condenses out of the hot ICM in thermal balance only when the ratio of the cooling time (t(cool)) and the free-fall time (t(ff)) is less than approximate to 10. Since thermal conduction is significant in the ICM and it suppresses local cooling at small scales, it is imperative to include thermal conduction in such studies. We find that anisotropic (along local magnetic field lines) thermal conduction does not influence the condensation criterion for a general magnetic geometry, even if thermal conductivity is large. However, with isotropic thermal conduction cold gas condenses only if conduction is suppressed (by a factor less than or similar to 0.3) with respect to the Spitzer value.