8,999 research outputs found

    The bioturbation transport of chemicals in surface soils

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    Large quantities of chemicals, such as pesticides, fertilizers, and industrial wastes, have been found throughout the environment raising concerns due to their ecological impacts and implications to human health. Soil is the most important repository of many organic chemicals in the environment. The objective of the present study was to determine the importance of the soil solid phase in the transport of chemicals in soils, and yield quantitative information to better describe bioturbation and its role in the movement of soil particles. Vertical movement of chemicals in the soil solid phase occurs by mixing mechanisms, such as bioturbation, cryoturbation, and dryoturbation. An extensive variety of soil-dwelling animals are responsible for bioturbation. Data on this process were located in the published literature, cataloged, and evaluated to estimate sorbed phase diffusion coefficients from soil turnover rates and effective depths reached by selected organisms. The impact of animals in soil processes varies depending on species, numbers, diversity, size, and feeding and burrowing behavior, which at the same time depend on soil properties, climate conditions, among others. Based on a 50% probability of occurrence, the approximated average depth of soil bioturbation was 20 cm. The periodic mixing of soil due to agricultural practices influences the sorbed phase transport of chemicals; representative numerical values of this type of “bioturbation” were estimated as well. Soil concentration profiles for selected PCBs were collected from literature and modeled. Model extracted sorbed phase diffusion coefficients of 4.03E-07, 5.98E-07, and 5.81E-07 m2/day were obtained for PCB-52, 153, and 101, respectively. These numerical chemical values were in agreement with bioturbation particle turnover values. For all congeners, percentage contribution of transport in the solid phase corresponded to more than 90% of the overall transport process. viii The model exercise provided valuable insights into the relative importance of the different soil transport mechanisms. It was concluded that PCBs are transported principally in association with the soil solid phase; their transport in air and water phases is insignificant. Therefore, chemical fate and transport models must account for the mixing of soil particles by bioturbation as it greatly influences the transport of chemicals sorbed to them

    Non-contraceptive applications of the levonorgestrel intrauterine system

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    Intrauterine progestins have many important current and potential gynecologic applications. This article describes the evidence for use of intrauterine progestin for common gynecologic conditions beyond its important role in contraception. The pharmacology of and selection criteria for use of the levonorgestrel intrauterine device is discussed, and the evidence for use of intrauterine progestin delivery for menorrhagia, endometriosis management, uterine fibroids, adenomyosis and endometrial hyperplasia is reviewed

    Role of Mo in catalysts based on noble metals in hydrodeoxygenation reactions

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    The use of bio-energy as a renewable alternative to fossil fuels is nowadays attracting more and more attention. The bio-fuel from biomass seems to be a potential energy substitute for fossil fuels since it is a renewable resource that could contribute to sustainable development and global environmental preservation and it appears to have significant economic potential1. The problem is its high oxygen content, which gives undesirable properties for combustion. To remove oxygen, catalytic hydrodeoxygenation (HDO) reactions are carried out. Monometallic Mo/Si, Pt/Si as well as bimetallic PtMo/Si catalysts were prepared and evaluated in the hydrodeoxygenation (HDO)reaction of dibenzofurane (DBF) as a model molecule in biomass derived bio-oil.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Essential Role of Lyn in Fibrosis.

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    Fibrotic disorders involve replacement of normal parenchyma with myofibroblasts, which deposit connective tissue, leading to obliteration of the function of the underlying organ. The treatment options are inadequate and reflect the fact that signaling targets in myofibroblasts are unknown. Here we identify the hyperactive Lyn signaling in myofibroblasts of patients with chronic pancreatitis-induced fibrosis. Lyn activation coexpress with markers of activated myofibroblasts, and is increased ~11-fold in chronic pancreatitis compared to normal tissue. Inhibition of Lyn with siRNA or INNO-406 leads to the substantial decrease of migration and proliferation of human chronic pancreatitis myofibroblasts in vitro, while leaving migration and proliferation of normal myofibroblasts only slightly affected. Furthermore, inhibition of Lyn prevents synthesis of procollagen and collagen in myofibroblasts in a mouse model of chronic pancreatitis-induced fibrosis. We conclude that Lyn, as a positive regulator of myofibroblast migration, proliferation, and collagen production, is a key target for preventing fibrosis

    Cardiovascular Mechanisms of Action of Anthocyanins May Be Associated with the Impact of Microbial Metabolites on Heme Oxygenase-1 in Vascular Smooth Muscle Cells

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    Anthocyanins are reported to have cardio-protective effects, although their mechanisms of action remain elusive. We aimed to explore the effects of microbial metabolites common to anthocyanins and other flavonoids on vascular smooth muscle heme oxygenase-1 (HO-1) expression. Thirteen phenolic metabolites identified by previous anthocyanin human feeding studies, as well as 28 unique mixtures of metabolites and their known precursor structures were explored for their activity on HO-1 protein expression in rat aortic smooth muscle cells (RASMCs). No phenolic metabolites were active when treated in isolation; however, five mixtures of phenolic metabolites significantly increased HO-1 protein expression (127.4-116.6%, p ≤ 0.03). The present study demonstrates that phenolic metabolites of anthocyanins differentially affect HO-1 activity, often having additive, synergistic or nullifying effects

    The effect of non-traditional cooling on dog sperm cryosurvival and ability to perform the acrosome reaction

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    The objective of this study was to assess cryosurvival, plasma membrane fluidity, and capability of cryopreserved dog (Canis lupus familiaris) spermatozoa, cooled to –5 °C before freezing, to perform the acrosome reaction under the effect of progesterone and calcium ionophore. In the first experiment, fresh spermatozoa diluted in Tyrode’s medium plus albumin, lactate, and pyruvate (TALP) were incubated at 38 °C in 5% CO2 in air, with progesterone or calcium ionophore added at 2, 4, and 6 h after incubation and sampled 30 min later to assess the acrosome reaction. In the second experiment, diluted sperm were packaged in plastic straws, cooled to either +5 °C or –5 °C and cryopreserved. Progressive motility, plasma membrane integrity and fluidity, capacitation status and acrosome integrity were assessed before and after freeze-thawing. After thawing, sperm were assessed, resuspended in TALP and incubated to assess the acrosome reaction. Parameters for sperm cryosurvival were similar in sperm cooled to either +5 °C or –5 °C, except in the percentage of hyper-fluid membranes which was lower (P<0.05) in sperm cooled to –5 °C. There were no differences in the percentages of frozen-thawed spermatozoa with acrosome reaction, induced by progesterone or calcium ionophore, between cooling treatments. In conclusion, cooling of dog spermatozoa to –5 °C did not improve sperm cryosurvival but had a positive effect on plasma membrane fluidity

    Soil Microbial Indicators within Rotations and Tillage Systems

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    Recent advancements in agricultural metagenomics allow for characterizing microbial indicators of soil health brought on by changes in management decisions, which ultimately affect the soil environment. Field-scale studies investigating the microbial taxa from agricultural experiments are sparse, with none investigating the long-term effect of crop rotation and tillage on microbial indicator species. Therefore, our goal was to determine the effect of rotations (continuous corn, CCC; continuous soybean, SSS; and each phase of a corn-soybean rotation, Cs and Sc) and tillage (no-till, NT; and chisel tillage, T) on the soil microbial community composition following 20 years of management. We found that crop rotation and tillage influence the soil environment by altering key soil properties, such as pH and soil organic matter (SOM). Monoculture corn lowered pH compared to SSS (5.9 vs. 6.9, respectively) but increased SOM (5.4% vs. 4.6%, respectively). Bacterial indicator microbes were categorized into two groups: SOM dependent and acidophile vs. N adverse and neutrophile. Fungi preferred the CCC rotation, characterized by low pH. Archaeal indicators were mainly ammonia oxidizers with species occupying niches at contrasting pHs. Numerous indicator microbes are involved with N cycling due to the fertilizer-rich environment, prone to aquatic or gaseous losses.Fil: Behnke, Gevan D.. University of Illinois at Urbana; Estados UnidosFil: Kim, Nakian. University of Illinois at Urbana; Estados UnidosFil: Zabaloy, Maria Celina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Riggins, Chance W.. University of Illinois at Urbana; Estados UnidosFil: Rodriguez Zas, Sandra. University of Illinois at Urbana; Estados UnidosFil: Villamil, Maria Bonita. University of Illinois at Urbana; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Association between chronic irritability and depressive symptoms in children and adolescents.

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    Association between chronic irritability and depressive symptoms in children and adolescents. Busto-Garrido, M.; Gutierrez-Castillo, D; Navas- Gonzalez, JR; Gutierrez-Bedmar, M; Gutierrez-Casares, JR; Martin-Lunar, MT; Rodríguez-Rosado, A; Pena-Andreu, JM. European Psychiatry 415(2017) 5221.Chronic irritability is the most frequently reported symptom in child and adolescent depression. The association of both has been linked with high rates of chronicity, comorbility and impairment. Objectives To study the association between chronic irritability and depressive symptoms in children and adolescents. Methods We have studied 857 participants recruited from the only Child and Adolescent Mental Health Clinic in a catchment area of 122968 people under 18 (2004-2010). A sample of 677 participants (57 controls and 620 patients) was included to carry out a cross-sectional study. Chronic irritability was measured by a Visual Analog Scale (VAS irritability) -scored from 0 to 10-, and depressive symptoms by the Children's Depression Inventory (CDI). The participants were categorized into controls and patients, and according to their chronic irritability (≤4 [I],5 [II] and ≥6 [III]). The mean of CDI score was calculated for each of the groups, adjusted by sex and age, and analyzed by ANCOVA. Results The following means were obtained from the controls: 13,71 (group I), 9,82 (group II) and 17,45 (group III). Regarding to the patients: 13,92 (group I), 11,54 (group II) and 15,64 (group III). A quadratic association (p <0,0015) was found between VAS irritability score and CDI score. Conclussions There is not a lineal association between chronic irritability and depressive symptoms in children and adolescent. High rates of depressive symptoms were associated both with high and low rates of irritability. Several questions remain unexplained about the status of irritability in psychiatry as Stringaris group has been pointed out. Disclosure statement I have no potential conflict of interest to discloseUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    A Longitudinal Study of the Microbial Basis of Nitrous Oxide Emissions Within a Long-Term Agricultural Experiment

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    Much of the global nitrous oxide emissions are derived from agricultural management driving microbial N transformations. Crop rotation, no-till, and cover cropping are feasible conservation agronomic strategies used to prevent N losses to the environment, though their effect on soil microbial N cycling at the field scale remains relatively unknown. Our goal was to determine the effect of crop rotation (continuous corn [Zea mays L.], CCC; and continuous soybean [Glycine max (L.) Merr.], SSS), tillage (no-till, NT; and chisel tillage, T), and cover crops (cover crop mixture, CC; and no cover crop, NCC) on the quantification of functional genes related to the N cycle from different times throughout the growing season. The study was conducted during the growing season of the cash crops following the first season of cover crops introduced after 23 years of management. Using quantitative polymerase chain reaction (qPCR) techniques, we quantified nifH (N2 fixation), amoA (nitrification) and nirK, nirS, and nosZ (denitrification). Our results show that CCC increased nitrous oxide emissions by 44% compared to SSS and reduced soil pH by nearly 1 unit. The reduction in soil pH, coupled with an increase in fertilizer-derived ammonium, caused ammonia-oxidizing bacteria (AOB) and nirK copy numbers to increase. The SSS rotation showed opposite results. Bacterial denitrification via the nirK pathway was likely the N cycle mechanism behind nitrous oxide emissions in CCC. The cover crop mixture of cereal rye [Secale cereale L.] and hairy vetch [Vicia villosa Roth] reduced soil nitrate levels, though they did increase nitrous oxide emissions, likely due to priming and the inclusion of a legume in the cover crop mixture. Nitrous oxide emissions were affected by sampling date, crop rotation, and cover crop use, suggesting management factors that add abundantly available N alter the microbial N cycle directly or indirectly. Chisel tillage increased the abundance of all N cycle genes compared to no-till. Together, our work adds further insight into the microbial N cycle, especially nitrous oxide evolution, from three common conservation agricultural management practices, contributing to our understanding of key soil biogeochemical processes.Fil: Behnke, Gevan D.. University of Illinois at Urbana; Estados UnidosFil: Kim, Nakian. University of Illinois at Urbana; Estados UnidosFil: Riggins, Chance W.. University of Illinois at Urbana; Estados UnidosFil: Zabaloy, Maria Celina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Rodriguez Zas, Sandra L.. University of Illinois at Urbana; Estados UnidosFil: Villamil, Maria Bonita. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. University of Illinois at Urbana; Estados Unido
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