193 research outputs found

    The Environmental Impacts of Trade Liberalization: A Quantitative Analysis for the United States Using TEAM

    Get PDF
    A highly disaggregated emissions factor model is presented. The model generates changes in emissions and resource use by state and 6-digit NAICS sector. Removal of all U.S. import restrictions is examined. Results for agriculture show that composition effects explain highly varied regional patterns of emission changes. Scale effects are also important for expanding sectors. Quantitative assessments such as this may prove useful in conducting full environmental reviews of U.S. trade agreements consistent with Executive Order 13141 and the Free Trade Act of 2002.trade, emissions, input-output, residuals, International Relations/Trade,

    The effects of HIV-1 regulatory TAT protein expression on brain reward function, response to psychostimulants and delay-dependent memory in mice

    Get PDF
    Depression and psychostimulant abuse are common comorbidities among humans with immunodeficiency virus (HIV) disease. The HIV regulatory protein TAT is one of multiple HIV-related proteins associated with HIV-induced neurotoxicity. TAT-induced dysfunction of dopamine and serotonin systems in corticolimbic brain areas may result in impaired reward function, thus, contributing to depressive symptoms and psychostimulant abuse. Transgenic mice with doxycycline-induced TAT protein expression in the brain (TAT+, TAT- control) show neuropathology resembling brain abnormalities in HIV+ humans. We evaluated brain reward function in response to TAT expression, nicotine and methamphetamine administration in TAT+ and TAT- mice using the intracranial self-stimulation procedure. We evaluated the brain dopamine and serotonin systems with high-performance liquid chromatography. The effects of TAT expression on delay-dependent working memory in TAT+ and TAT- mice using the operant delayed nonmatch-to-position task were also assessed. During doxycycline administration, reward thresholds were elevated by 20% in TAT+ mice compared with TAT- mice. After the termination of doxycycline treatment, thresholds of TAT+ mice remained significantly higher than those of TAT- mice and this was associated with changes in mesolimbic serotonin and dopamine levels. TAT+ mice showed a greater methamphetamine-induced threshold lowering compared with TAT- mice. TAT expression did not alter delay-dependent working memory. These results indicate that TAT expression in mice leads to reward deficits, a core symptom of depression, and a greater sensitivity to methamphetamine-induced reward enhancement. Our findings suggest that the TAT protein may contribute to increased depressive-like symptoms and continued methamphetamine use in HIV-positive individuals

    The bullies are the leaders of the next generation : Inherited aminergic neurotransmitter system changes in socially dominant zebrafish, Danio rerio

    Get PDF
    We studied the social hierarchy in zebrafish and assessed differences in neurotransmitters and behavior in the F1 generation offspring of dominant and subordinate zebrafish (Danio rerio). We used behavioral assays to study locomotion, ability to complete cognitive tasks, social interaction and aggression. To study the neurochemical changes, we applied quantitative polymerase chain reaction, high pressure liquid chromatography and immunohistochemistry. Social hierarchies were formed both by males and females when animals were kept in same sex pairs in the dyadic dominant-subordinate hierarchy test. The offspring of dominant animals were the leaders in social interactions, however aggression in the mirror-test was not altered in any group. Serotonin and noradrenaline levels were lower in the F1 generation subordinate animals when compared with dominant animals, but not compared with animals that were naive to social hierarchy. The mRNA level of the rate-limiting enzyme in histamine synthesis, histidine decarboxylase, was significantly lower in dominant and subordinate larval zebrafish when compared with control animals. In the dominant adult zebrafish tyrosine hydroxylase 1 mRNA level was lower compared with control animals, whereas tyrosine hydroxylase 2 mRNA was not different. The result was verified with immunohistochemistry. There were gender specific differences between the dominant and subordinate animals, where the dominant females performed better in cognitive tasks such as the T-maze than subordinate females. This was not observed in males, as the behavior of the dominant and subordinate males did not differ. These results add to the understanding of the plastic nature of the central nervous system and show that neurochemical features in aminergic neurotransmitter systems are associated with social leadership and dominance.Peer reviewe

    Kvantitativne karakteristike mikrostrukture građevinskih kompozita

    Get PDF
    The article deals with the algorithm of the building material structure based on its photomicrographs by means of point images statistical analysis. The obtained values allow the defining of the basic characteristics of the material structure.U radu se razmatra algoritam strukture građevinskog materijala na temelju njegove fotomikrografije pomoću statističke analize točkastih slika. Dobivene vrijednosti omogućavaju definiranje osnovnih karakteristika strukture materijala

    Innovation as a Factor in Sustainable Development of Russia’s Agriculture

    Get PDF
    Sustainable agriculture is an integral aspect of the sustainable development of a socio-economic system. In this regard, innovation is considered to be one of the leading factors ensuring the development of sustainable agricultural since it increases the efficiency and competitiveness of the industry in the domestic and foreign markets. This study presents a system of recursive equations characterizing the innovations occurring within agricultural organizations in the regions of the Russian Federation. Additionally, the study assesses the sustainability of agricultural development in Russia by calculating the integrated index of five components: economic, innovative, social, ecological, and institutional. Also, the authors built a regression model that estimates the influence of innovation on the sustainability of agricultural development in Russia

    Abnormal behavior, striatal dopamine turnover and opioid peptide gene expression in histamine-deficient mice

    Get PDF
    Hypothalamic histaminergic neurons regulate a variety of homeostatic, metabolic and cognitive functions. Recent data have suggested a modulatory role of histamine and histamine receptors in shaping striatal activity and connected the histaminergic system to neuropsychiatric disorders. We characterized exploratory behavior and striatal neurotransmission in mice lacking the histamine producing enzyme histidine decarboxylase (Hdc). The mutant mice showed a distinct behavioral pattern during exploration of novel environment, specifically, increased frequency of rearing seated against the wall, jumping and head/body shakes. This behavioral phenotype was associated with decreased levels of striatal dopamine and serotonin and increased level of dopamine metabolite DOPAC. Gene expression levels of dynorphin and enkephalin, opioids released by medium spiny neurons of striatal direct and indirect pathways respectively, were lower in Hdc mutant mice than in control animals. A low dose of amphetamine led to similar behavioral and biochemical outcomes in both genotypes. Increased striatal dopamine turnover was observed in Hdc KO mice after treatment with dopamine precursor l-Dopa. Overall, our study suggests a role for striatal dopamine and opioid peptides in formation of distinct behavioral phenotype of Hdc KO mice.Peer reviewe

    Storage of neural histamine and histaminergic neurotransmission is VMAT2 dependent in the zebrafish

    Get PDF
    Monoaminergic neurotransmission is greatly dependent on the function of the vesicular monoamine transporter VMAT2, which is responsible for loading monoamines into secretory vesicles. The role of VMAT2 in histaminergic neurotransmission is poorly understood. We studied the structure and function of the histaminergic system in larval zebrafish following inhibition of VMAT2 function by reserpine. We found that reserpine treatment greatly reduced histamine immunoreactivity in neurons and an almost total disappearance of histamine-containing nerve fibers in the dorsal telencephalon and habenula, the most densely innervated targets of the hypothalamic histamine neurons. The reserpine treated larvae had an impaired histamine-dependent dark-induced flash response seen during the first second after onset of darkness, implying that function of the histaminergic network is VMAT2 dependent. Levels of histamine and other monoamines were decreased in reserpine treated animals. This study provides conclusive evidence of the relevance of VMAT2 in histaminergic neurotransmission, further implying that the storage and release mechanism of neural histamine is comparable to that of other monoamines. Our results also reveal potential new insights about the roles of monoaminergic neurotransmitters in the regulation of locomotion increase during adaptation to darkness.Peer reviewe

    Effects of HIV/TAT protein expression and chronic selegiline treatment on spatial memory, reversal learning and neurotransmitter levels in mice

    Get PDF
    Neurotoxic viral protein TAT may contribute to deficits in dopaminergic and cognitive function in individuals infected with human immunodeficiency virus. Transgenic mice with brain-specific doxycycline-induced TAT expression (TAT+, TAT- control) show impaired cognition. However, previously reported TAT-induced deficits in reversal learning may be compromised by initial learning deficits. We investigated the effects of TAT expression on memory retention/recall and reversal learning, and neurotransmitter function. We also investigated if TAT-induced effects can be reversed by improving dopamine function with selegiline, a monoamine oxidase inhibitor. Mice were tested in the Barnes maze and TAT expression was induced after the task acquisition. Selegiline treatment continued throughout behavioral testing. Dopamine, serotonin and glutamate tissue levels in the prefrontal/orbitofrontal cortex, hippocampus and caudate putamen were measured using high performance liquid chromatography. Neither TAT expression nor selegiline altered memory retention. On day 2 of reversal learning testing, TAT+ mice made fewer errors and used more efficient search strategies than TAT- mice. TAT expression decreased dopamine turnover in the caudate putamen, increased serotonin turnover in the hippocampus and tended to increase the conversion of glutamate to glutamine in all regions. Selegiline decreased dopamine and serotonin metabolism in all regions and increased glutamate levels in the caudate putamen. In the absence of impaired learning, TAT expression does not impair spatial memory retention/recall, and actually facilitates reversal learning. Selegiline-induced increases in dopamine metabolism did not affect cognitive function. These findings suggest that TAT-induced alterations in glutamate signaling, but not alterations in monoamine metabolism, may underlie the facilitation of reversal learning

    Impacto de los cambios causados por la pandemia en el estado actual y desarrollo de las empresas de petróleo y gas

    Get PDF
    En el artículo se presentan los resultados de la investigación sociológica en la industria del petróleo y el gas, que revelan los cambios sociales recientes con un gran impacto en el mercado ruso del petróleo y el gas y el sistema de gestión de personal. El artículo trata sobre las razones demográficas y el papel de la pandemia, que puso en peligro a los post-millennials. Los autores revalúan el impacto de la digitalización en la Generación Z, que llevó a la reducción de nativos digitales trabajadores, ya que no vivirán para trabajar, pero trabajarán para vivir. Se ha analizado el género, la edad y las características profesionales de los empleados de las empresas de petróleo y gas, así como el estado actual y las tendencias de desarrollo del mercado laboral. El artículo enfatiza la prioridad de las características individuales de las "personas digitales", en lugar de la cantidad de personal y el nivel salarial de los empleados. Esta visión resultó de la nueva realidad de la pandemia de COVID-19, las tendencias geopolíticas, la política de sanciones, la difusión global de las tecnologías digitales, la combinación de orientaciones socioeconómicas y el desarrollo personal. Estas personas no están dispuestas a depender de nadie, pero el gerente ideal para ellos es el que establece las tareas de manera más clara y definida
    corecore