Extinction re-examined and re-analyzed: a new theory.

In reality there are various kinds of explanations for each type of extinction. This paper introduces a new theory to explain and to estimate the size and frequency of all extinctions over the entire period of 600 my of the fossil record. The central point was the search for a common pattern and even one common formula. The explanation seemed to be excellent. We will demonstrate in what way death is a fact of life: by making calculations with the new formula: there is a constant margin of 10 pct, and about seven peaks with at least 25 pct of extinction victims. Those peaks occur each 85 million years, but their frequency has increased over time. In principle, the predictability of the next peak is limited, because of chaos (within the solar system and the ecosystem on Earth), the unpredictability of mutations in Nature, of innovations by Man, and let alone the disastrous impacts of asteroids. It also depends on the concept of whether life is cyclical or linear. Therefore, some predictions have a low likelihood of occurrence. In the traditional theory or old vision there are many extinctions and even mass extinctions, each with various theories believed to be their cause. There is no single theory explaining all extinctions. Man was witness to and perhaps later on even guilty of extinctions. Even as early as in the ice ages he tried to find facts and continued later on in the age of science. But we still do not see extinctions in their right perspective, and it would be very useful to change this. The right perspective depends on the modern vision on the structure of the world that is in the chaotic solar system, with changing orbits of the planets. Key words: Extinction, mutation, chaos, ecology, evolution, falsification, prediction, catastrophe, radiation, asteroid, foraminifers, formula, orbit, Venus, Mars, Earth, volcanism.

In stellar astrophysics, the determination of the magnitude of interstellar extinction is critical, due to its effect on the observed brightness and colour of the stars. Extinction is therefore an important factor in deriving scientific information from the colour-magnitude diagrams (CMDs) of stellar populations. The treatment of extinction in standard CMD analyses is to employ constant ratios of extinction in each photometric filter relative to the visual Johnson-V filter, denoted AX/AV in a generic filter X. This work presents a theoretical analysis of the behaviour of the extinction ratios AX/AV in multiple photometric systems as the values of three stellar parameters (effective temperature, surface gravity and metallicity) are varied. The results of this analysis show significant variations in the value of AX/AV with changes in the stellar parameters. For certain ultraviolet filters and an AV value of 1.0, the fractional flux lost to extinction is up to two orders of magnitude greater between different stellar atmospheres. Analytic functions of these stellar parameters are proposed to describe these variations. Also presented is an application of these functions to generic isochrones in multiple photometric filter systems. This was followed by an application of the extinction-ratio functions to the highly-reddened star cluster NGC 6793 whose members also have accurate Gaia parallax measurements. When a proper analysis of extinction, via the AX=AV functions, is used on the cluster data, it is shown that there is a non-negligible impact on the age determination for the cluster in multiple CMD axes and in different filter systems. For NGC 6793, the observational data predicts an age of 603 Myr, an AV value of 0.843 and a metallicity of [Fe/H] = 0.0 when the extinction in each filter is held constant. When the extinction is allowed to vary according to the AX/AV functions, the predicted values for these parameters become 500 Myr, 1.1 and +0.062, respectively. The uncertainties in the observational data, the models and all other factors considered were found to be insufficiently large to render the difference between these results insignificant. It was therefore concluded that changing the method of calculating extinction in isochrones results in a significant change in cluster parameter estimates, particularly for the age and AV values.

Biodiversity indices often combine data from different species when used in monitoring programs. Heuristic properties can suggest preferred indices, but we lack objective ways to discriminate between indices with similar heuristics. Biodiversity indices can be evaluated by determining how well they reflect management objectives that a monitoring program aims to support. For example, the Convention on Biological Diversity requires reporting about extinction rates, so simple indices that reflect extinction risk would be valuable. We developed 3 biodiversity indices that are based on simple models of population viability that relate extinction risk to abundance. We based the first index on the geometric mean abundance of species and the second on a more general power mean. In a third index, we integrated the geometric mean abundance and trend. These indices require the same data as previous indices, but they also relate directly to extinction risk. Field data for butterflies and woodland plants and experimental studies of protozoan communities show that the indices correlate with local extinction rates. Applying the index based on the geometric mean to global data on changes in avian abundance suggested that the average extinction probability of birds has increased approximately 1% from 1970 to 2009.Conectando Índices para el Monitoreo de la Biodiversidad con la Teoría de Riesgo de ExtinciónResumenLos índices de biodiversidad combinan frecuentemente los datos de diferentes especies cuando se usan en los programas de monitoreo. Las propiedades heurísticas pueden sugerir índices preferidos, pero carecemos de medios objetivos para discriminar a los índices con propiedades heurísticas similares. Los índices de biodiversidad pueden evaluarse al determinar qué tan bien reflejan los objetivos de manejo que un programa de monitoreo busca apoyar. Por ejemplo, la Convención sobre la Diversidad Biológica requiere reportar las tasas de extinción, así que los índices que reflejan el riesgo de extinción serían valiosos. Desarrollamos 3 índices de biodiversidad que se basan en modelos sencillos de viabilidad de población y que relacionan el riesgo de extinción con la abundancia. Basamos el primer índice en la media geométrica de la abundancia de especies, y el segundo en una media de poder más general. En el tercer índice integramos la media geométrica y la tendencia. Estos índices requieren los mismos datos que índices previos, pero también se relacionan directamente con el riesgo de extinción. La información de campo sobre mariposas y plantas de bosque, y los estudios experimentales de comunidades protozoarias, muestran que los índices se correlacionan con las tasas locales de extinción. Al aplicar el índice basado en la media geométrica sobre los datos globales de los cambios en la abundancia de aves, sugirió que la probabilidad de extinción promedio de aves ha incrementado aproximadamente 1% desde 1970 hasta 2009.Palabras ClaveÍndice de biodiversidad, media geométrica, medida de la biodiversidad, riesgo de extinción

Three experiments tested the prediction, derived from generalized frustration theory (Amsel, 1972), that habituation to behaviourally disruptive stimuli increases resistance to extinction in the runway. In each experiment, rats received initial consistent reinforcement (CRF) training and then either continued CRF (Groups C), partial reinforcement (PRF) training (Groups P), or CRF accompanied by presentations of a novel tactile, tone, or obstacle stimulus (Groups D) in Experiments 1-3, respectively. PRF increased resistance to extinction whether non-reinforcement disrupted behaviour (Experiment 1) or not (Experiments 2 and 3). The tactile and obstacle stimuli very substantially disrupted behaviour, and the tone produced a modest disruption of behaviour. All subjects habituated to the disruptive effects of these stimuli, but Group D was not more resistant to extinction than Group C in any experiment. The results suggest that non-reinforcement has unique stimulus properties, a consequence of which is that habituation to other sources of disruptive stimulation does not promote responding to non-reinforcement in extinction.

The adaptive polarization conversion system which converts the non-polarization maintaining laser to polarization maintaining one based on stochastic parallel gradient descent (SPGD) algorithm is reported in this paper. Using polarization controller to control polarized component in X and Y direction directly, adopting SPGD optimization technology to optimize the output extinction ratio, it finally realizes polarization conversion of non-polarization maintaining laser to polarization maintaining one. In theory, the model of adaptive polarization conversion is built based on the principle of the controller and the SPGD algorithm. In experiment, we first realized adaptive conversion of non-polarization maintaining laser to polarization maintaining one with an extinction ratio of 14.1 dB. Then we used the system to change the polarization direction of the linearly polarized laser from any direction (0-360) to the expected direction with high extinction ratio, and the average extinction ratio is about 12 dB.

The far-field optical technology of single gold-nanorod(AuNR) has attracted a great deal of attention in recent years. Because of special local surface plasmon resonance (LSPR) property, AuNR particles have high conductivity of optical signals localized on the surface from physical or chemical irritants. The mechanism, application, progress and novel optical characteristics of AuNRs in optical detection and spectroscopy method are being reviewed in our work. The paper describes an overall introduction as follows: (1)various related technologies on AuNR scattered spectrum, including dark-field technology, homodyne and heterodyne technology, photonic crystal technology, spatial modulation, polarization modulation technology, etc; (2) the properties of AuNR scattered spectrum, including spectral line-shape functions, effects of line-width and substrate, comparison of theoretical and experimental spectrums, etc; (3) the development of related spectrum technologies in recent years. The paper focuses on the method of far-field optical scattering based on LSPR and mainly discusses the linear method based on AuNRs, such as direct and indirect scattering detection method. We also put emphasis upon studying the importance of medium environment (for example, substrate, the molecules combined on surface and other nanomaterials) and the influence on scattered spectrum and the extinction rate. Of particular note is the quantitative method and correlation studies of AuNR’s surface and morphology, and its character is that most of the methods are compared with theoretical model and experiments in terms of accuracy. The combination of the experiments and theoretical tools can be used to explain the optical properties of single gold-nanorod particle in detail.

If you asked this question a generation ago, you would have learned that about 65 million years ago climatic change probably affected the sluggish, mal-adapted dinosaurs and gradually carried them off to extinction. Then, in the 1970s, the theory of plate tectonics suggested that a great episode of volcanic activity led to a severe environmental decline and catastrophic die-off of the dinosaurs and many other species. More recently, a spectacular new hypothesis claims that an asteroid impact wiped out the dinosaurs in one of the most cataclysmic extinctions in Earth history. What is the evidence for each of these explanations, and how do paleontologists view them today? We will have a look at the evidence and the possible causes for dinosaur extinction. We will also look for an answer to an even more surprising question – Did all dinosaurs really go extinct? Some paleontologists contend that birds are the living descendants of ancient dinosaurs. If true, does this mean that dinosaurs are still alive?

Bright pulsating variables, such as Cepheids and RR Lyrae, are prime probes of the structure of both the young and old stellar components of the Milky Way. However, the far side of the Galactic disk has not yet been mapped using such variables as tracers, due to the severe extinction caused by foreground interstellar dust. In this thesis, the near-infrared light curves from the VISTA Variables in the Via Lactea survey are utilized to penetrate these regions of high extinction and thus discover thousands of previously “hidden” Cepheid and RR Lyrae variables. The analysis of the light curves of RR Lyrae variables, was performed with a newly developed fitting algorithm, and their metallicities determined from their near-infrared light-curve shapes, using a newly developed method. These photometric metal abundances, combined with their positions within the Galactic disk, lend support to theories of an early, inside-out formation of the Galactic disk. The newly discovered Cepheids were classified into the old (Type II) and young (Classical) subtypes. A new near-infrared extinction law was determined using the Type II Cepheids, taking advantage of their concentration around the Galactic center. The distribution of the Classical Cepheids in the Galactic disk follows both the Galactic warp and the flare of the Galactic disk at large Galactocentric radii. A first attempt has been made to connect the current locations of the Classical Cepheids to the spiral arm structure of the Milky Way.

Interstellar dust was first identified through the extinction that it causes of optical starlight. Initially, observational and theoretical studies of extinction were made to identify simple ways of removing the effect of extinction. Over the last few decades it has become clear that dust has a number of very important roles in interstellar physics and chemistry, and that through these roles dust affects quite fundamentally the evolution of the Milky Way and other galaxies. However, our detailed knowledge of the actual material of dust remains relatively poor. The use of accurate models for the interaction of electromagnetic radiation with particles of arbitrary shape and composition remains vital, if our description of dust is to improve.

The challenge of reducing global carbon emissions by 50-85 per cent by the year 2050, which is suggested by the Intergovernmental Panel on Climate Change (2007a) as a target compatible with limiting the risk of a more-than-2∫C temperature increase, clearly conflicts with existing patterns of economic growth, which are heavily dependent on increased use of fossil fuel energy. While it is theoretically possible to conceive of economic growth being ìdelinkedî from fossil fuel consumption, any such delinking would represent a drastic change from economic patterns of the last 150 years. Current macroeconomic theory is heavily oriented towards an assumption of continuous, exponential growth in GDP. The historical record shows GDP growth is strongly correlated with a parallel record of increasing fossil energy use and CO2 emissions. A path of reduced carbon emissions would require major modifications in economic growth patterns. Climate change is part of an inter-related group of environmental issues associated with growth limits. These include population growth, agricultural production, water supplies, and species loss. To achieve a low-carbon path requires population stabilization, limited consumption, and major investments in environmental protection and social priorities such as public health, nutrition, and education. Macroeconomic theory must be adapted to reflect these new realities. A reclassification of macroeconomic aggregates is proposed to distinguish between those categories of goods and services that can expand over time, and those that must be limited to reduce carbon emissions. This reformulation makes it clear that there are many possibilities for environmentally beneficial economic expansion. New forms of Keynesian policy oriented towards ecological sustainability, provision of basic social needs such as education and health care, and distributional equity can provide a basis for a rapid reduction in carbon emissions while promoting investment in human and natural capital.

Understanding the causes of spatial variation in species richness is a major research focus of biogeography and macroecology. Gridded environmental data and species richness maps have been used in increasingly sophisticated curve-fitting analyses, but these methods have not brought us much closer to a mechanistic understanding of the patterns. During the past two decades, macroecologists have successfully addressed technical problems posed by spatial autocorrelation, intercorrelation of predictor variables and non-linearity. However, curve-fitting approaches are problematic because most theoretical models in macroecology do not make quantitative predictions, and they do not incorporate interactions among multiple forces. As an alternative, we propose a mechanistic modelling approach. We describe computer simulation models of the stochastic origin, spread, and extinction of species' geographical ranges in an environmentally heterogeneous, gridded domain and describe progress to date regarding their implementation. The output from such a general simulation model (GSM) would, at a minimum, consist of the simulated distribution of species ranges on a map, yielding the predicted number of species in each grid cell of the domain. In contrast to curve-fitting analysis, simulation modelling explicitly incorporates the processes believed to be affecting the geographical ranges of species and generates a number of quantitative predictions that can be compared to empirical patterns. We describe three of the 'control knobs' for a GSM that specify simple rules for dispersal, evolutionary origins and environmental gradients. Binary combinations of different knob settings correspond to eight distinct simulation models, five of which are already represented in the literature of macroecology. The output from such a GSM will include the predicted species richness per grid cell, the range size frequency distribution, the simulated phylogeny and simulated geographical ranges of the component species, all of which can be compared to empirical patterns. Challenges to the development of the GSM include the measurement of goodness of fit (GOF) between observed data and model predictions, as well as the estimation, optimization and interpretation of the model parameters. The simulation approach offers new insights into the origin and maintenance of species richness patterns, and may provide a common framework for investigating the effects of contemporary climate, evolutionary history and geometric constraints on global biodiversity gradients. With further development, the GSM has the potential to provide a conceptual bridge between macroecology and historical biogeography.

School refusal behavior refers to the avoidance of a child attending school and/or persistent difficulty staying in the classroom throughout the school day. Based on a review of the scientific literature, the purpose of this study are: first, examine the pattern of school refusal from the perspective of psychoanalytic theory; the theory of behavioral and cognitive theory. Recognizing the background, trigger school refusal and intervention strategies. This paper concludes that: first, the school refusal background in psychoanalytic is from separation anxiety and hallucinations, in the cases studied student are frightened to his teacher manifested as though seeing a ghost in the classroom and outside the classrooms. In Cognitive view, the background of the school refusal i.e.: affected by irrational beliefs of students to the school. In behavioristic theory argues that school refusal as a learned response to specific stimuli associated with the school environment. The triggering factors of the school refusal i.e.: a) the child has anxiety, such as (separation anxiety), b) the fear experienced by children related to academic activities, c) a parent is sick or conflict in the family, d) the intensity of stress while at school in caused because teachers or a friends at school. Parents profile who triggered the school refusal i.e.: the parents who often took his son away and let their children do not attend school, and parents quarrel. Interventions for reducing school refusal behavior can vary in strategies i.e.: cognitive restructuring, reframing, exposure (systematic desensitization, in vivo desensitization), differential reinforcement, modeling, and extinction. Article visualizations:

In this thesis, thermal-diffusive instabilities are studied experimentally in diffusion flames. The novel species injector of a recently developed research burner, consisting of an array of hypodermic needles, which allows to produce quasi one-dimensional unstrained diffusion flames has been improved. It is used in a new symmetric design with fuel and oxidizer injected through needle arrays which allows to independently choose both the magnitude and direction of the bulk flow through the flame. A simplified theoretical model for the flame position, the temperature and the species concentration profiles with variable bulk flow is presented which accounts for the transport properties of both reactants. The model results are compared to experiments with a CO2-diluted H2-O2 flame using variable bulk flow and inert mixture composition. The mixture composition throughout the burning chamber is monitored by mass spectrometry. An elaborate calibration procedure has been implemented to account for the variation of the mass spectrometer sensitivity as a function of the mixture composition. The calibrated results allow the effective mixture strength of the diffusion flames to be measured with a relative uncertainty of about 5 %. In order to properly characterize the flame produced, the velocity and temperature distribution inside the burning chamber are measured. The resulting species concentration and temperature profiles are compared to the simplified theory and demonstrate that the new burner configuration produces a good approximation of the 1-D chambered diffusion flame, which has been used extensively for the stability analysis of diffusion flames. The velocity profiles are also used to quantify the residual stretch experienced by the flame which is extremely low, below 0.15 s-1. Hence, this new research burner opens up new possibilities for the experimental validation of theoretical models developed in the idealized unstrained 1-D chambered flame configuration. The thermal-diffusive instabilities observed close to extinction are investigated experimentally and mapped as a function of the Lewis numbers of the reactants. The use of a mixture of two inerts (helium and CO2) allows for the effect of a wide range of Lewis numbers to be studied. A cellular flame structure is observed in hydrogen flames when the Lewis numbers is relatively low with a typical cell size between 7 and 15 mm. The cell size is found to scale linearly with the diffusion length, in good agreement with theoretical predictions. When the Lewis number is increased by using a higher helium content in the dilution mixture, the instabilities observed are planar intensity pulsation. The use of methane allowed pulsating flames to be generated for a wide range of bulk velocities and transport properties. The pulsating frequencies measured are in the 0.7 to 11 Hz range and were found to scale linearly with a diffusion frequency defined as U2/Dth multiplied by the square root of the Damkohler number. The experimental results presented here are the first observations of thermal-diffusive instabilities in such a low-strain flame. They constitute a unique dataset that can be used to quantitatively validate theoretical models on diffusion flame stability developed in the simplified one-dimensional configuration.

Various Mie scattering systems, each having a transparent matrix, are studied in the mid-infrared region. Our three theoretical scattering systems correspond to a lossless scatterer, an anomalous dispersive dielectric scatterer and a metal scatterer, each in a non-air usual matrix. The refractive-index effects of the matrix on scattering and extinction efficiencies in the mid-infrared region are found to be quite different in different cases. Although the non-air usual matrix reduces scattering and extinction efficiencies in the first kind of system, it may or may not help scatter and extinguish the mid-infrared radiation in the second, and it has little effect on them in the third.

The field of plasmonics exploits the unique optical properties of metallic nanostructures to concentrate and manipulate light at subwavelength length scales. Metallic nanostructures get their unique properties from their ability to support surface plasmons– coherent wave-like oscillations of the free electrons at the interface between a conductive and dielectric medium. Recent advancements in the ability to fabricate metallic nanostructures with subwavelength length scales have created new possibilities in technology and research in a broad range of applications. In the first part of this thesis, we present two investigations of the relationship between the charge state and optical state of plasmonic metal nanoparticles. Using experimental bias-dependent extinction measurements, we derive a potential- dependent dielectric function for Au nanoparticles that accounts for changes in the physical properties due to an applied bias that contribute to the optical extinction. We also present theory and experiment for the reverse effect– the manipulation of the carrier density of Au nanoparticles via controlled optical excitation. This plasmoelectric effect takes advantage of the strong resonant properties of plasmonic materials and the relationship between charge state and optical properties to eluci- date a new avenue for conversion of optical power to electrical potential. The second topic of this thesis is the non-radiative decay of plasmons to a hot-carrier distribution, and the distribution’s subsequent relaxation. We present first-principles calculations that capture all of the significant microscopic mechanisms underlying surface plasmon decay and predict the initial excited carrier distributions so generated. We also preform ab initio calculations of the electron-temperature dependent heat capacities and electron-phonon coupling coefficients of plasmonic metals. We extend these first-principle methods to calculate the electron-temperature dependent dielectric response of hot electrons in plasmonic metals, including direct interband and phonon-assisted intraband transitions. Finally, we combine these first-principles calculations of carrier dynamics and optical response to produce a complete theoretical description of ultrafast pump-probe measurements, free of any fitting parameters that are typical in previous analyses.