scholarly journals Reply to ‘Climate of doubt: a re-evaluation of Büntgen and Di Cosmo’s environmental hypothesis for the Mongol withdrawal from Hungary, 1242 CE’

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Ulf Büntgen ◽  
Nicola Di Cosmo
Keyword(s):  
Environmental Hypothesis

Addiction and schizophrenia

2000 ◽  
Vol 15 (2) ◽  
pp. 115-122 ◽  
Author(s):  
P. Batel
Keyword(s):  
Epidemiologic Studies ◽  
Self Medication ◽  
Addictive Disorders ◽  
Co Morbidity ◽  
Dependency Type ◽  
Active Research ◽  
Social Environmental ◽  
High Level ◽  
Environmental Hypothesis ◽  
High Degree

SummaryEpidemiologic studies in the general population and those based on the clinical assessment of schizophrenic populations have revealed a high degree of overlap between schizophrenia and addictive disorders. The abuse of psychoactive substances (including alcohol) throughout life is so frequent (50%) that the possibility of a specific link inevitably arises. Various hypotheses have been suggested to explain the high co-morbidity between schizophrenia and addiction: 1) The social-environmental hypothesis has been developed but studies have provided poor evidence to validate it. 2) The possible shared biological vulnerability between schizophrenia and addictions led researchers to explore common genetic determinants and study the involvement of the dopaminergic and opioid systems in the aetiology of both schizophrenia and the abuse of and dependence on psychoactive drugs. 3) Finally, the theory of self-medication suggests that schizophrenics may be attempting to counter the deficit linked to their disorders by using the substances they take or their dependency-type behaviour to cope with their emotional problems. The clinical profile of schizophrenic addicts does seem to display some distinctive features, such as the high level of depressive co-morbidity, very high nicotine and alcohol dependence, with a very poor prognosis. These patients are difficult to manage; the possibility of pharmacologic interactions between the substances they are taking and neuroleptic medication calls for prudence, and their compliance is also poor. Addictive disorders in schizophrenics are currently a topic of active research intended to lead to identifying specific treatments. The early identification of addictive disorders in schizophrenics should make it possible to limit their development and improve the prognosis.

Social Determinants of Racial Prejudice

1989 ◽  
Vol 32 (4) ◽  
pp. 469-483 ◽  
Author(s):  
Charles E. Case ◽  
Andrew M. Greeley ◽  
Stephan Fuchs
Keyword(s):  
Social Class ◽  
Social Determinants ◽  
Environmental Variables ◽  
Racial Prejudice ◽  
Class Conflict ◽  
Research Center ◽  
Occupational Prestige ◽  
National Opinion Research ◽  
Material Resources ◽  
Environmental Hypothesis

In the sociology of racial prejudice, two major paradigms can be distinguished: Cultural-environmental and social class or conflict paradigms. On the basis of Durkheimian theory, it is hypothesized that cultural-environmental variables (education, knowledge) offer stronger and more consistent explanations of racial prejudice than status variables (self-perceived class position, occupational prestige, income). To test this hypothesis, National Opinion Research Center (NORC) data are analyzed. Findings corroborate the major cultural-environmental hypothesis that racial prejudice emerges from ritually dense sociocultural lifeforms. Little support is found for the claim that prejudice arises from class conflict and competition over material resources.

scholarly journals Is Testicular Germ Cell Cancer Estrogen Dependent? The Role of Endocrine Disrupting Chemicals

Endocrinology ◽  
2019 ◽  
Vol 160 (12) ◽  
pp. 2981-2989 ◽  
Author(s):  
Patrick Fénichel ◽  
Nicolas Chevalier
Keyword(s):  
Germ Cell ◽  
Cell Cancer ◽  
Endocrine Disrupting Chemicals ◽  
Young Male ◽  
Germ Cell Cancer ◽  
Testicular Germ Cell ◽  
Endocrine Disrupting ◽  
Genetic And Environmental Factors ◽  
Testicular Germ Cell Cancer ◽  
Environmental Hypothesis

Abstract Testicular germ cell cancer (TGCC) is the most frequent cancer of the young male, with an increasing incidence worldwide. The pathogenesis and reasons for this increase remain unknown. However, epidemiological and experimental data have suggested that, similar to genital malformations and sperm impairment, it could result from the interaction of genetic and environmental factors including fetal exposure to endocrine-disrupting chemicals (EDCs) with estrogenic effects. In this review, we analyze the expression of classic and nonclassic estrogen receptors by TGCC cells, the way they may influence germ cell proliferation induced by EDCs, and discuss how this estrogen dependency supports the developmental and environmental hypothesis.

scholarly journals Characteristics of the mitochondrial and cellular uptake of MPP+, as probed by the fluorescent mimic, 4′I-MPP+

2018 ◽  
Author(s):  
Mapa S.T. Mapa ◽  
Viet Q. Le ◽  
Kandatege Wimalasena
Keyword(s):  
Dopaminergic Neurons ◽  
Apoptotic Cell ◽  
Current Model ◽  
Critical Role ◽  
Atp Depletion ◽  
Live Cells ◽  
Sodium Calcium Exchanger ◽  
Pharmacological Agents ◽  
Dopaminergic Cells ◽  
Environmental Hypothesis

AbstractThe discovery that 1-methyl-4-phenylpyridinium (MPP+) selectively destroys dopaminergic neurons and causes Parkinson’s disease (PD) symptoms in mammals has strengthened the environmental hypothesis of PD. The current model for the dopaminergic toxicity of MPP+ is centered on the uptake into dopaminergic neurons, accumulation into the mitochondria, inhibition of the complex-I leading to ATP depletion, increased reactive oxygen species (ROS) production, and apoptotic cell death. However, some aspects of this mechanism and the details of the cellular and mitochondrial accumulation of MPP+ are still poorly understood. The aim of this study was to characterize a structural and functional MPP+ mimic which is suitable to study the cellular distribution and mitochondrial uptake of MPP+ in live cells and use it to identify the molecular details of these processes to advance the understanding of the mechanism of the selective dopaminergic toxicity of MPP+. Here we report the characterization of the fluorescent MPP+ derivative, 1-methyl-4-(4’-iodophenyl)pyridinium (4’I-MPP+), as a suitable candidate for this purpose. Using this novel probe, we show that cytosolic/mitochondrial Ca2+ play a critical role through sodium-calcium exchanger (NCX) in the mitochondrial and cellular accumulation of MPP+ suggesting for the first time that MPP+ and related mitochondrial toxins may also exert their toxic effects through the perturbation of Ca2+ homeostasis in dopaminergic cells. We also found that the specific mitochondrial NCX (mNCX) inhibitors protect dopaminergic cells from the MPP+ and 4’I-MPP+ toxicity, most likely through the inhibition of the mitochondrial uptake, which could potentially be exploited for the development of pharmacological agents to protect the central nervous system (CNS) dopaminergic neurons from PD-causing environmental toxins.

scholarly journals Evolutionary determinants of morphological polymorphism in colonial animals

2016 ◽  
Author(s):  
Carl Simpson ◽  
Jeremy B.C. Jackson ◽  
Amalia Herrera-Cubilla
Keyword(s):  
Life Histories ◽  
Competitive Ability ◽  
Environmental Variability ◽  
Temporal Position ◽  
Costs And Benefits ◽  
Isthmus Of Panama ◽  
Modular Units ◽  
Environmental Hypothesis ◽  
Colonial Ascidians

AbstractColonial animals commonly exhibit morphologically polymorphic modular units that are phenotypically distinct and specialize in specific functional tasks. But how and why these polymorphic modules have evolved is poorly understood. Across colonial invertebrates there is wide variation in the degree of polymorphism from none in colonial ascidians, to extreme polymorphism in siphonophores such as the Portuguese Man of War. Bryozoa are a phylum of exclusively colonial invertebrates that uniquely exhibit almost the entire range of polymorphism from monomorphic species to others that rival siphonophores in their polymorphic complexity. Previous approaches to understanding the evolution of polymorphism have been based upon analyses of (1) the functional role of polymorphs or (2) presumed evolutionary costs and benefits based upon evolutionary theory that postulates polymorphism should only be evolutionarily sustainable in more “stable” environments because polymorphism commonly leads to the loss of feeding and sexual competence. Here we use bryozoans from opposite shores of the Isthmus of Panama to revisit the environmental hypothesis by comparison of faunas from distinct oceanographic provinces that differ greatly in environmental variability and we then examine the correlations between the extent of polymorphism in relation to patterns of ecological succession and variation in life histories. We find no support for the environmental hypothesis. Distributions of the incidence of polymorphism in the oceanographically unstable Eastern Pacific are indistinguishable from those in the more stable Caribbean. In contrast, the temporal position of species in a successional sequence is collinear with the degree of polymorphism because species with fewer types of polymorphs are competitively replaced by species with higher numbers of polymorphs on the same substrata. Competitively dominant species also exhibit patterns of growth that increase their competitive ability. The association between degrees of polymorphism and variations in life histories is fundamental to understanding of the macroevolution of polymorphism.

scholarly journals IMMERSIVE WAYFINDING: VIRTUAL RECONSTRUCTION AND EYE-TRACKING FOR ORIENTATION STUDIES INSIDE COMPLEX ARCHITECTURE

2019 ◽  
Vol XLII-2/W9 ◽  
pp. 143-150 ◽  
Author(s):  
F. Bianconi ◽  
M. Filippucci ◽  
N. Felicini
Keyword(s):  
3D Visualization ◽  
Digital Simulation ◽  
Digital Tools ◽  
Tsinghua University ◽  
Virtual Reconstruction ◽  
Immersive Environment ◽  
Architectural Survey ◽  
Environmental Hypothesis ◽  
Complex Architecture ◽  
Multiple Configurations

<p><strong>Abstract.</strong> The study presents a process of digital simulation that aims to investigate the legibility of multiple spaces in a complex architecture through architectural survey, virtual reconstruction and 3D visualization in immersive environment. The collaboration between two research institutions, one Italian and the other Chinese, developed a reconstruction of a building in the campus of the Tsinghua University of Beijing using digital tools, in order to understand the behaviours during the fruition of that space. Digital simulation in the visibility theme guarantees the possibility of testing multiple configurations and showing the impacts of the different environmental hypothesis.</p>

Left-Handedness in Twin Families: Support of an Environmental Hypothesis

1987 ◽  
Vol 64 (1) ◽  
pp. 155-170 ◽  
Author(s):  
Kristian Tambs ◽  
Per Magnus ◽  
Kåre Berg
Keyword(s):  
Age Groups ◽  
Twin Studies ◽  
Genetic Effect ◽  
Small Sample ◽  
Left Hand ◽  
Sibling Pairs ◽  
Chi Squared ◽  
Twin Families ◽  
Environmental Hypothesis ◽  
Hand Writing

Information on handedness, assessed as writing-hand, was collected from 197 MZ twin pairs and 203 DZ twin pairs and from their parents, spouses, and children. Associations for pairs of relatives were studied by 2 × 2 tables, computing chi squared-values and tetrachoric correlations. Correlations of about .3 were obtained for mother-offspring and sibling pairs, while for cousins the correlation was .25 (in a small sample). No other significant associations were found, not even for twins. These results suggest only a small, if any, genetic effect, and only a small environmental between family effect, most of which seems to be a maternal effect. The lack of cotwin correlations and correlations for one of the twins with her/his ordinary brothers/sisters suggest the existence of an effect specific to twins, since the correlation for pairs of ordinary siblings is significant. Conclusions drawn from twin studies alone may be biased. The frequency of left-hand writers has increased from 1% to 10% in the different age groups born during the last century in Norway This age effect is present mainly in hand writing and not so much in handedness generally, suggesting a decrease in cultural repression against left-hand writing.

TWINAN: Twin Data Analysis Program for Microcomputers

1985 ◽  
Vol 34 (1-2) ◽  
pp. 113-114 ◽  
Author(s):  
Ke Won Kang
Keyword(s):  
Data Analysis ◽  
Computer Program ◽  
Genetic Parameters ◽  
Statistical Significance ◽  
Analysis Program ◽  
Twin Data ◽  
Data Analysis Program ◽  
Environmental Hypothesis ◽  
Twin Data Analysis

AbstractA BASIC computer program designed to facilitate analysis of twin data is presented. The program estimates genetic parameters and tests their statistical significance based on the genetic and environmental hypothesis.

GLOBAL DIMMING - AN ENVIRONMENTAL HYPOTHESIS ON CLIMATE CHANGE

2008 ◽  
Vol 7 (4) ◽  
pp. 417-421
Author(s):  
Ioan Craciun ◽  
Ion Giurma ◽  
Catrinel-Raluca Giurma-Handley ◽  
Constantin-Marin Antohi
Keyword(s):  
Climate Change ◽  
Global Dimming ◽  
Environmental Hypothesis
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