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1.
Waste Manag ; 76: 643-651, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29573926

RESUMEN

"Fossetto" landfill has been operating in the municipality of Monsummano Terme (Pistoia Province, Italy) since 1988; the authorized volume for landfilling is about 1,000,000 m3; at the moment the plant is being mainly used to dispose of mechanically and biologically treated residual municipal solid waste. Since September 2006, an in-situ reverse osmosis leachate treatment plant has been operating to treat leachate. The treated water is being discharged into a small nearby stream while the concentrated leachate is being recirculated back into the landfill body following Italian Regulations and an authorization from the local authority (Pistoia Province). This paper presents monitoring results on leachate generation rates and composition for the past fifteen years. A moderate increase of the concentration of some of the monitored parameters occurred (e.g. ammonium, chlorides) and a decrease for most heavy metals. The increase of concentrations for Cl- and NH4+ was more evident in the leachate coming from the wells closer to reinjection area. However, the change in leachate composition did not affect the quality of the effluent from the leachate treatment plant. The annual volume of the generated leachate increased significantly right after the recirculation started.


Asunto(s)
Ósmosis , Eliminación de Residuos , Contaminantes Químicos del Agua , Italia , Instalaciones de Eliminación de Residuos
2.
Rev Sci Instrum ; 83(9): 094501, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23020397

RESUMEN

The VLT survey telescope is the latest telescope installed at European Southern Observatory's Paranal observatory that is considered one of the best sites for optical astronomy for the excellent seeing conditions. The exceptional quality of the site imposes tight requirements for the telescope tracking system that shall perform very well to fully exploit the extreme sharpness of the Chilean sky. We describe the specific solutions adopted for pointing, servo and guiding systems and the results obtained during the commissioning of the telescope. The hardware implementation relies on industry components and the control solutions privilege both the performance and the future maintainability of the system.

3.
Neuroscience ; 163(1): 1-8, 2009 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-19531374

RESUMEN

Traumatic brain injury (TBI) induces a number of pathological events ranging from neuronal degeneration and tissue loss to impaired neuronal plasticity and neurochemical dysregulation. In rodents, exposure of brain-injured animals to environmental enrichment has been shown to be an effective means of enhancing learning and memory post-injury. Recently, it has been discovered that environmental enrichment may enhance neuronal plasticity through epigenetic changes that involve enhanced histone acetylation, a property that can be mimicked by the use of histone deactylase (HDAC) inhibitors. We therefore evaluated the consequences of the HDAC inhibitor sodium butyrate on the learning and memory of brain-injured mice. In contrast to a previous report using a mouse neurodegeneration model, sodium butyrate (1.2 g/kg daily for four weeks) did not improve learning and memory when tested after the completion of the drug treatment paradigm. In addition, sodium butyrate administration during the reported period of neurodegeneration (days 0-5) also offered no benefit. However, when administered concurrently with training in the Morris water maze task (beginning on day 14 post-injury), sodium butyrate improved learning and memory in brain-injured mice. Interestingly, when these mice were subsequently tested in an associative fear conditioning task, an improvement was observed. Taken together, our findings indicate that HDAC inhibition may mimic some of the cognitive improvements seen following enriched environment exposure, and that the improvement is observed when the treatment is carried out current with behavioral testing.


Asunto(s)
Terapia Conductista/métodos , Lesiones Encefálicas/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Butiratos/uso terapéutico , Histona Desacetilasa 1/antagonistas & inhibidores , Discapacidades para el Aprendizaje/tratamiento farmacológico , Trastornos de la Memoria/tratamiento farmacológico , Animales , Reacción de Prevención/efectos de los fármacos , Reacción de Prevención/fisiología , Encéfalo/enzimología , Encéfalo/fisiopatología , Lesiones Encefálicas/enzimología , Lesiones Encefálicas/genética , Butiratos/farmacología , Condicionamiento Psicológico/efectos de los fármacos , Condicionamiento Psicológico/fisiología , Modelos Animales de Enfermedad , Ambiente Controlado , Epigénesis Genética/efectos de los fármacos , Epigénesis Genética/genética , Histona Desacetilasa 1/genética , Histona Desacetilasa 1/metabolismo , Discapacidades para el Aprendizaje/enzimología , Discapacidades para el Aprendizaje/genética , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Aprendizaje por Laberinto/fisiología , Trastornos de la Memoria/enzimología , Trastornos de la Memoria/genética , Ratones , Ratones Endogámicos C57BL , Degeneración Nerviosa/tratamiento farmacológico , Degeneración Nerviosa/enzimología , Degeneración Nerviosa/genética , Plasticidad Neuronal/genética , Estimulación Física
4.
Nature ; 458(7238): 607-9, 2009 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-19340076

RESUMEN

Antiparticles account for a small fraction of cosmic rays and are known to be produced in interactions between cosmic-ray nuclei and atoms in the interstellar medium, which is referred to as a 'secondary source'. Positrons might also originate in objects such as pulsars and microquasars or through dark matter annihilation, which would be 'primary sources'. Previous statistically limited measurements of the ratio of positron and electron fluxes have been interpreted as evidence for a primary source for the positrons, as has an increase in the total electron+positron flux at energies between 300 and 600 GeV (ref. 8). Here we report a measurement of the positron fraction in the energy range 1.5-100 GeV. We find that the positron fraction increases sharply over much of that range, in a way that appears to be completely inconsistent with secondary sources. We therefore conclude that a primary source, be it an astrophysical object or dark matter annihilation, is necessary.

5.
Phys Rev Lett ; 102(5): 051101, 2009 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-19257498

RESUMEN

A new measurement of the cosmic-ray antiproton-to-proton flux ratio between 1 and 100 GeV is presented. The results were obtained with the PAMELA experiment, which was launched into low-Earth orbit on-board the Resurs-DK1 satellite on June 15th 2006. During 500 days of data collection a total of about 1000 antiprotons have been identified, including 100 above an energy of 20 GeV. The high-energy results are a tenfold improvement in statistics with respect to all previously published data. The data follow the trend expected from secondary production calculations and significantly constrain contributions from exotic sources, e.g., dark matter particle annihilations.

6.
Neuroscience ; 159(2): 483-91, 2009 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-19167462

RESUMEN

The prefrontal cortex is highly vulnerable to traumatic brain injury (TBI) resulting in the dysfunction of many high-level cognitive and executive functions such as planning, information processing speed, language, memory, attention, and perception. All of these processes require some degree of working memory. Interestingly, in many cases, post-injury working memory deficits can arise in the absence of overt damage to the prefrontal cortex. Recently, excess GABA-mediated inhibition of prefrontal neuronal activity has been identified as a contributor to working memory dysfunction within the first month following cortical impact injury of rats. However, it has not been examined if these working memory deficits persist, and if so, whether they remain amenable to treatment by GABA antagonism. Our findings show that working memory dysfunction, assessed using both the delay match-to-place and delayed alternation T-maze tasks, following lateral cortical impact injury persists for at least 16 weeks post-injury. These deficits were found to be no longer the direct result of excess GABA-mediated inhibition of medial prefrontal cortex neuronal activity. Golgi staining of prelimbic pyramidal neurons revealed that TBI causes a significant shortening of layers V/VI basal dendrite arbors by 4 months post-injury, as well as an increase in the density of both basal and apical spines in these neurons. These changes were not observed in animals 14 days post-injury, a time point at which administration of GABA receptor antagonists improves working memory function. Taken together, the present findings, along with previously published reports, suggest that temporal considerations must be taken into account when designing mechanism-based therapies to improve working memory function in TBI patients.


Asunto(s)
Lesiones Encefálicas/complicaciones , Trastornos de la Memoria/etiología , Memoria a Corto Plazo/fisiología , Análisis de Varianza , Animales , Bicuculina/farmacología , Lesiones Encefálicas/patología , Espinas Dendríticas/diagnóstico por imagen , Espinas Dendríticas/patología , Modelos Animales de Enfermedad , Antagonistas del GABA/farmacología , Masculino , Aprendizaje por Laberinto/fisiología , Trastornos de la Memoria/patología , Memoria a Corto Plazo/efectos de los fármacos , Neuronas/patología , Neuronas/ultraestructura , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/patología , Desempeño Psicomotor/efectos de los fármacos , Desempeño Psicomotor/fisiología , Cintigrafía , Ratas , Ratas Sprague-Dawley , Tiempo de Reacción , Tinción con Nitrato de Plata/métodos , Factores de Tiempo
8.
Int J Clin Pharmacol Res ; 10(5): 265-70, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2127771

RESUMEN

The kinetic profile in tonsils of cefonicid has been studied in 30 patients who underwent tonsillectomy after administration of a single intramuscular dose of 1 g. Blood and tissue samples were withdrawn 1, 2, 3, 6, 12 and 24 h after administration of the drug. The analytical determination was performed employing a microbiological method. Peak serum levels appeared at the first hour (94.2 +/- 9.83 mg/l), while peak tissue values were determined in samples collected at the third hour (11.9 +/- 3.68 mg/kg). Serum levels at the 24th hour were 3.82 +/- 1.25 mg/l. Levels in the tonsils were 7.54 +/- 2.96 mg/kg at the sixth hour, 3.34 +/- 1.42 mg/kg at the twelfth hour and 0.40 +/- 0.31 mg/kg at the 24th hour.


Asunto(s)
Cefonicid/farmacocinética , Tonsila Palatina/metabolismo , Adolescente , Adulto , Bacillus subtilis/efectos de los fármacos , Bioensayo , Cefonicid/administración & dosificación , Femenino , Semivida , Humanos , Inyecciones Intramusculares , Masculino
9.
Int J Clin Pharmacol Res ; 9(4): 293-6, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2789197

RESUMEN

Diffusion of miokamycin into gum, maxillary-mandibular bone and crevicular fluid was studied in human beings. The antibiotic concentrations were determined in specimens at different times after oral administration of 600 mg in a single dose of miokamycin. Peak serum levels (2.32 +/- 0.67 mcg/ml) were found at the first hour after dosage. In healthy gum tissue the highest antibiotic levels (1.44 +/- 0.34 mcg/gr) were observed at the second hour, while in the inflamed gum miokamycin penetrates more rapidly, being, as in serum at the highest levels detectable during the first hour. In the bone of the maxilla or mandible the highest levels of miokamycin (0.88 +/- 0.13 mcg/gr) were detected at the second hour after treatment. In the crevicular fluid miokamycin showed a similar profile as that in serum, since the peak levels were reached at the first hour (2.4 +/- 0.88 mcg/ml, but the decrease of the antibiotic occurred more slowly than in serum. Miokamycin rapidly penetrates into tissues and fluids of oral cavity. A single oral dose of 600 mg guarantees antibacterial levels against susceptible bacteria over six hours.


Asunto(s)
Antibacterianos/farmacocinética , Encía/análisis , Leucomicinas/farmacocinética , Mandíbula/análisis , Maxilar/análisis , Saliva/análisis , Administración Oral , Adulto , Anciano , Antibacterianos/análisis , Antibacterianos/sangre , Humanos , Leucomicinas/análisis , Leucomicinas/sangre , Persona de Mediana Edad , Miocamicina , Factores de Tiempo
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