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1.
Nat Commun ; 12(1): 1683, 2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33727536

RESUMEN

The mild activity of basaltic volcanoes is punctuated by violent explosive eruptions that occur without obvious precursors. Modelling the source processes of these sudden blasts is challenging. Here, we use two decades of ground deformation (tilt) records from Stromboli volcano to shed light, with unprecedented detail, on the short-term (minute-scale) conduit processes that drive such violent volcanic eruptions. We find that explosive eruptions, with source parameters spanning seven orders of magnitude, all share a common pre-blast ground inflation trend. We explain this exponential inflation using a model in which pressure build-up is caused by the rapid expansion of volatile-rich magma rising from depth into a shallow (<400 m) resident magma conduit. We show that the duration and amplitude of this inflation trend scales with the eruption magnitude, indicating that the explosive dynamics obey the same (scale-invariant) conduit process. This scale-invariance of pre-explosion ground deformation may usher in a new era of short-term eruption forecasting.

2.
Chaos ; 30(3): 033135, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32237785

RESUMEN

The present paper concerns a new description of changing in metabolism during incremental exercises test that permit an individually tailored program of exercises for obese subjects. We analyzed heart rate variability from RR interval time series (tachogram) with an alternative approach, the recurrence quantification analysis, that allows a description of a time series in terms of its dynamic structure and is able to identify the phase transitions. A transition in cardiac signal dynamics was detected and it perfectly reflects the aerobic threshold, as identified by gas exchange during an incremental exercise test, revealing the coupling from the respiratory system toward the heart. Moreover, our analysis shows that, in the recurrence plot of RR interval, it is possible to identify a specific pattern that allows to identify phase transitions between different dynamic regimes. The perfect match of the occurrence of the phase transitions with changes observed in the VO2 consumption, the gold standard approach to estimate thresholds, strongly supports the possibility of using our analysis of RR interval to detect metabolic threshold. In conclusion, we propose a novel nonlinear data analysis method that allows for an easy and personalized detection of thresholds both from professional and even from low-cost wearable devices, without the need of expensive gas analyzers.


Asunto(s)
Prueba de Esfuerzo , Frecuencia Cardíaca , Obesidad , Consumo de Oxígeno , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/fisiopatología
3.
Phys Rev Lett ; 115(1): 014801, 2015 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-26182099

RESUMEN

We present the experimental evidence of the generation of coherent and statistically stable two-color free-electron laser radiation obtained by seeding an electron beam double peaked in energy with a laser pulse single spiked in frequency. The radiation presents two neat spectral lines, with time delay, frequency separation, and relative intensity that can be accurately controlled. The analysis of the emitted radiation shows a temporal coherence and a shot-to-shot regularity in frequency significantly enhanced with respect to the self-amplified spontaneous emission.


Asunto(s)
Electrones , Rayos Láser , Color , Simulación por Computador , Procesamiento de Imagen Asistido por Computador , Análisis Espectral/instrumentación , Análisis Espectral/métodos
4.
Brain Res ; 1269: 68-89, 2009 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-19146837

RESUMEN

Although it has been suggested that the standardized Ginkgo biloba leaf extract (Egb 761) may have a beneficial effect on memory, the cellular and molecular changes that underlie this process are not yet well defined. The present study evaluated the effects of acute (one dose) or subacute treatments (one daily dose/seven days) with EGb 761 (0.5 g kg(-1) and 1.0 g kg(-1)) on rats submitted to a conditioned emotional response (CER) in comparison with positive (4 mg kg(-1) Diazepam) and negative (12%Tween 80) control groups. To this end, eighty (n=10/group) adult, male, Wistar rats (+/-250-300 g) were used in an off-baseline CER procedure. We here observed that the rats submitted to an acute and subacute EGb 761 treatments had acquisition of fear conditioning. Additionally, we investigate if the expression of genes previously associated with classical conditioning (CREB-1 and GAP-43) and new candidate genes (GFAP) are modulated following EGb 761 acute treatment. CREB-1, GAP-43 and GFAP mRNA and protein expressions were evaluated using both quantitative PCR (qPCR) and immunohistochemical analysis, respectively. We here show, for the first time, that EGb 761 modulated GAP-43, CREB-1 and GFAP expression in the prefrontal cortex, amygdala and hippocampus. We observed an underexpression of GAP-43 in all structures evaluated and over-expression of GFAP in the amygdala and hippocampus following acute G. biloba treatment when compared to control group (Tween; p<0.01). GAP-43 expression was decreased in prefrontal cortex and hippocampus in the subacute treatment with EGb 761. Subacute treatment with EGb 761 lead to a decreased CREB-1 in mPFC (p<0.001) and increased in the hippocampus to 1.0 g kg(-1)G. biloba group (p<0.001). The results obtained from immunohistochemical analysis support our aforementioned findings and revealed that the changes in expression occurred within specific regions in the areas evaluated. All together, our findings not only provide new evidence for a role of EGb 761 on memory but also identify molecular changes that underlie the fear memory consolidation.


Asunto(s)
Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Ginkgo biloba , Memoria/efectos de los fármacos , Extractos Vegetales/farmacología , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/fisiología , Animales , Encéfalo/fisiología , Condicionamiento Psicológico/efectos de los fármacos , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Miedo , Proteína GAP-43/genética , Expresión Génica/efectos de los fármacos , Proteína Ácida Fibrilar de la Glía/genética , Hipocampo/efectos de los fármacos , Hipocampo/fisiología , Masculino , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/fisiología , Ratas , Ratas Wistar
6.
Bioresour Technol ; 86(2): 123-9, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12653276

RESUMEN

The paper concerns the results of a pilot-scale study of the simulation of the start-up phase of the thermophilic semi-dry anaerobic digestion of the organic fraction of municipal solid wastes. The aim of the study was to aid and shorten the start-up phase of the full-scale plant (500 t/d) in Verona--Ca' del Bue, where the semi-dry anaerobic digestion process is being used. The substrate used in the experimentation was the mechanically sorted organic fraction of municipal solid waste (MS-OFMSW) enriched with the putrescent fraction from the source sorted OFMSW in order to simulate the substrate which is dealt with in the Verona plant. The results of the pilot scale study agreed with literature data and previous work of the authors: it showed a specific gas production of 0.23 m3/kg TVSfeed and a gas production rate of 2.1 m3/m3 d when operating at a specific organic loading rate of 0.135 kgTVSfeed/kgTVSreacter d. No problems regarding process stability were encountered in the gradual acclimation of the biomass. The design organic loading rate of 9 kg TVSfeed/m3reactor d was reached in about 30 days, during which the total solids content in the feedwas increased. Only a partial comparison with the full scale start-up, which is now in progress, is possible: this shows an initial general concordance with the results found in previous work.


Asunto(s)
Reactores Biológicos , Eliminación de Residuos/métodos , Bacterias Anaerobias/fisiología , Biomasa , Arquitectura y Construcción de Instituciones de Salud , Compuestos Orgánicos/metabolismo , Temperatura , Agua
7.
Water Sci Technol ; 46(10): 199-208, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12479472

RESUMEN

The paper deals with the performances of the mesophilic anaerobic digestion treatment of sewage sludge from a full scale BNR process without primary settling (nominally 300,000 PE). A relation between the activated sludge observed yields, Y(obs), and the anaerobic digester performance was preliminarily found: for values of Y(obs) of 0.25 kgVSS/kgCOD the anaerobic digester specific gas production showed the best performances (0.22 m3/kgVS(fad)). This has to be confirmed with wider future studies. It was also shown the level of sludge pre-thickening to be reached for the self-sustaining warming of the digester also in wintertime. According to the energetic balance and to a comparison with an aerobic stabilisation process, it was pointed out as when a co-generation unit for heat and energy production was introduced about 3.4 kWh/PE y of energy were produced in the anaerobic digestion process. On the other hand, 4.3 kWh/PE y were spent if an aerobic stabilisation process was applied. The economic assessment, carried out on the basis of the energy balances, showed that the anaerobic digestion is always economically advantageous if compared to aerobic stabilisation processes, also for small WWTPs. According to the energetic evaluations an environmental balance was assessed, in terms of CO2 emissions. The difference between anaerobic and aerobic processes was about 5.3 kgCO2/PE y in favour of anaerobic processes application.


Asunto(s)
Reactores Biológicos , Nitrógeno/aislamiento & purificación , Fósforo/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Bacterias Anaerobias/fisiología , Estaciones del Año , Volatilización
8.
Water Sci Technol ; 44(1): 187-94, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11496672

RESUMEN

The aim of this study is to demonstrate the denitrification potential enhancement determined by the addition of the anaerobic fermentation products from the organic fraction of municipal solid waste in BNR wastewater treatment plants. The denitrification potential rose from 6 to 17 mgNO3-N/l thanks to the good performances showed by the fermentation products in the denitrification step: a typical maximum denitrification rate of about 5 mgN/gVSS d was observed. This value is similar to those obtained by using pure organic substrates. The denitrification capacity increase is determined by a significant increase of S8 and Xs availability in the influent due to the anaerobic fermentation products addition which leads to an influent COD increase equal to 68% of the total load: this value is significantly higher than the one obtained by fermentation of primary and/or waste activated sludge (3-5%).


Asunto(s)
Bacterias Anaerobias/fisiología , Nitrógeno/metabolismo , Eliminación de Residuos/métodos , Contaminación Ambiental/prevención & control , Fermentación , Modelos Teóricos , Oxígeno/metabolismo
9.
Biodegradation ; 11(6): 407-14, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11587445

RESUMEN

A pilot scale mesophilic anaerobic acidogenic fermenter was fed with mixtures of vegetables and fruits shredded by a hammer mill and mixed in a stock tank, in order to produce a liquid phase suitable as RBCOD source in denitrification and EBPR processes. Different operative conditions were studied working with a HRT in the range 1-12 days. The effluent coming from the fermenter was screw pressed, and the solid phase was recycled adopting different ratios to the fermenter, in order to define its effect on the final liquid phase composition. The variations of the VFA, lactate, methyl and ethyl alcohol concentrations, TCOD, SCOD and pH during more than one year were analysed and discussed both with reference to the fresh feed, and to the content of the fermenter. It was found that almost all the organic matter in the liquid phase inside the fermenter was represented by VFA (mainly acetate), lactate (in particular) and methyl and ethyl alcohols when HRT was longer than 6 days.


Asunto(s)
Fermentación , Frutas , Verduras , Ácidos
10.
Int J Parasitol ; 27(5): 495-506, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9193943

RESUMEN

The nasal bot fly, Oestrus ovis, was investigated to establish which specific cuticular component is most immunogenic to infested sheep and how larval cuticle attains a protective role, if any, against the host immune system. To accomplish these goals, larval cuticle was extracted by a variety of agents and tested against immune sera from infested sheep and experimentally immunized rabbits. The cuticle substructure remaining after extraction was examined to localize various immunogenic components. O. ovis larval integument comprises an inner cellular layer, the epidermis, and an overlying cuticle layer. In 3rd instar larvae, the cuticle comprises 2 additional layers: the procuticle with numerous pore canals and the epicuticle which includes the wax canals. Three additional layers, altogether comprising the cuticulin layer, are present external to the epicuticle. The epicuticle is completed by apposition of an amorphous electrondense material extending for up to 1 micron in thickness. When fixed with ruthenium red, cuticle becomes heavily stained all along the epicuticular surface in larvae of all developmental stages. However, in 3rd instar larvae, ruthenium red deposits are restricted to the cuticulin layer alone. By gel electrophoresis, 3rd instar larval cuticle is shown to contain a number of polypeptides ranging in molecular weight from 180 to 4.5 kDa. The number and relative concentration of low molecular weight polypeptides was shown to vary in relation to the extraction media employed. Cuticular fragments examined after extraction exhibit an altered ultrastructure. When tested by immunoblotting, the cuticular polypeptides most reactive against sheep antisera are in the range of 180-56 kDa. A similar reaction was also detected with sera from rabbits infested experimentally with O. ovis larvae. Results are interpreted in relation to differential polypeptide distribution within the larval cuticle and to accessibility of the host immune system.


Asunto(s)
Antígenos/inmunología , Dípteros/ultraestructura , Proteínas de Insectos/inmunología , Larva/ultraestructura , Miasis/veterinaria , Enfermedades de las Ovejas/inmunología , Animales , Dípteros/química , Dípteros/inmunología , Sueros Inmunes/inmunología , Immunoblotting , Proteínas de Insectos/química , Larva/química , Larva/inmunología , Microscopía Electrónica , Peso Molecular , Miasis/inmunología , Péptidos/química , Péptidos/inmunología , Conejos , Ovinos
11.
Vet Parasitol ; 60(3-4): 273-82, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8747910

RESUMEN

Tissue extracts from larval instars of the sheep nasal bot, Oestrus ovis, were resolved by gel electrophoresis under both native and denaturing conditions. Polypeptides resolved under these conditions were tested by immunoblotting against sera of infested sheep. Of all tissues examined in this study, salivary glands proved to be major immunogens in infested sheep. Salivary gland polypeptides were also detected in the washing solution as larval secretory products (LSP). To a minor extent, a few polypeptides from the larval cuticle were also found to be immunogenic, but they did not contribute to LSP. These results were further corroborated by nasal infestation of rabbits that also developed specific antibodies against larval salivary gland polypeptides from Oestrus ovis.


Asunto(s)
Antígenos/inmunología , Dípteros/inmunología , Miasis/veterinaria , Proteínas y Péptidos Salivales/inmunología , Enfermedades de las Ovejas , Animales , Antígenos/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Immunoblotting , Larva , Miasis/inmunología , Nariz , Conejos/inmunología , Proteínas y Péptidos Salivales/aislamiento & purificación , Ovinos
13.
Arch Ital Urol Androl ; 65(3): 261-4, 1993 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-8334449

RESUMEN

Laparoscopy is a safe and reliable procedure for treatment of cryptorchid testicle, varix ligation, staging of lymph nodes in prostatic and in bladder cancer. Recently this procedure is adopted in management of renal cysts. From 2/92 to 7/92, we performed laparoscopic assessment in 31 patients: in 15 cases for varicocelectomy, in 9 for renal cysts, in 2 for lymph nodes dissection, in 3 for preoperatory evaluation, in 1 for unpalpable testicle and in 1 case for ileal perforation in orthotopic neobladder. In 1 case the procedure was unsuccessful because of damage of the spleen. All the patients were mobilized within 1 day postoperative treatment and discharged within 3 days. There are many present and potential application of laparoscopic surgery in urologic pathology, but we think that this technique must be carefully applied in order to avoid complications.


Asunto(s)
Laparoscopía , Femenino , Humanos , Enfermedades Renales Quísticas/cirugía , Escisión del Ganglio Linfático/métodos , Masculino , Varicocele/cirugía
14.
G Chir ; 13(10): 489-92, 1992 Oct.
Artículo en Italiano | MEDLINE | ID: mdl-1467149

RESUMEN

After the good results of "necessary" conservative surgery in the treatment of kidney neoplasms (bilateral neoplasms, congenital, acquired or functional solitary kidney), conservative surgery itself has been employed as elective treatment in selected cases presenting without the overmentioned problems. The authors report two cases of elective conservative surgery in kidney neoplasm with good results after 18 and 24 months.


Asunto(s)
Carcinoma de Células Renales/cirugía , Neoplasias Renales/cirugía , Anciano , Carcinoma de Células Renales/epidemiología , Carcinoma de Células Renales/patología , Femenino , Estudios de Seguimiento , Humanos , Riñón/cirugía , Neoplasias Renales/epidemiología , Neoplasias Renales/patología , Escisión del Ganglio Linfático , Metástasis Linfática , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Estadificación de Neoplasias
16.
Arch Ital Urol Nefrol Androl ; 64(2): 109-14, 1992 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-1380727

RESUMEN

Some tests are subject to the influence of a special kind of "irreducible" effects which do not satisfy the Central Limit Theorem of statistics, even though they show no systematic character or tendency. These effects especially present when physiological experiments are concerned "in vivo". In such the lack of specific methods to reduce these effects brings about the necessity of special case in minimizing the loss of information. Contained in the experimental data as well as the accumulation of useless information. Recent work has suggested the extensive use of several indexes derived from combination of available variables and their respective mathematic correlation. The information obtained by following this methodology has the character of "working hypothesis" so it needs many favorable confirmation to assess its reliability. It is convenient to analyze a large number of relations in order to emphasize the concordant effects and discord the others. In order to obtain some preliminary indication of the reliability of this procedure we have analyzed some CMG curves in prostatic and non-prostatic subject. The final slope of the curves (urge point) t = dP/dVr has been adapted as an index of the "elasticity" of the bladder; it was compared with the filling volume, the muscular volume and their ratio, i.e. with a geometric index of the bladder shape. The correlation show that the index t can, to some extent significantly represent the mechanical behaviour of the bladder in its physiological condition or when there is a partial obstruction of urine deflection.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Artefactos , Interpretación Estadística de Datos , Manometría , Hiperplasia Prostática/fisiopatología , Obstrucción Uretral/fisiopatología , Vejiga Urinaria/fisiopatología , Urodinámica , Elasticidad , Humanos , Masculino , Hiperplasia Prostática/complicaciones , Obstrucción Uretral/etiología
17.
Minerva Chir ; 46(23-24): 1245-50, 1991 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-1803288

RESUMEN

Using the study as a basis for a novel interpretation of the pH-metric curve, the paper reports the results of a study carried out in a sample group of 11 normo-secretory subjects (students from the Faculty of Medicine and Surgery). The pH-metric curve was assessed over 24 hours using a portable pH measuring device.


Asunto(s)
Determinación de la Acidez Gástrica , Monitoreo Fisiológico , Adulto , Femenino , Humanos , Concentración de Iones de Hidrógeno , Masculino
18.
G Chir ; 12(5): 323-7, 1991 May.
Artículo en Italiano | MEDLINE | ID: mdl-1931525

RESUMEN

In presenting and describing the pathogenesis of the pyeloureteral junction syndrome, the Authors report their recent experience with four cases due to an "abnormal vessel". Symptoms, diagnosis, and surgical techniques are discussed.


Asunto(s)
Vasos Sanguíneos/anomalías , Pelvis Renal/irrigación sanguínea , Uréter/irrigación sanguínea , Obstrucción Ureteral , Adulto , Femenino , Humanos , Pelvis Renal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Síndrome , Uréter/diagnóstico por imagen , Obstrucción Ureteral/diagnóstico por imagen , Obstrucción Ureteral/etiología , Obstrucción Ureteral/cirugía , Urografía
19.
Respiration ; 54 Suppl 1: 49-58, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3068745

RESUMEN

In the last 13 years, bronchoalveolar lavage has been widely used to study the mechanisms involved in the defense of the lower respiratory tract and in the pathogenesis of a variety of lung disorders. This technique, which is a relatively safe and simple extension of fiberoptic bronchoscopy, has been proved to be a powerful investigative tool with enormous potential since it has enhanced our knowledge on a variety of disorders, including interstitial lung diseases, lung destruction associated to cigarette smoking and, recently, bronchial asthma. In addition, bronchoalveolar lavage has also been utilized as an interesting test to help in the diagnostic procedures and in the management of patients with a variety of pulmonary diseases. Its actual importance in clinical respiratory medicine, however, is still under debate and the value of some suggested applications remains to be established.


Asunto(s)
Líquido del Lavado Bronquioalveolar/citología , Neumología , Asma/patología , Broncoscopía , Tecnología de Fibra Óptica , Humanos , Fibrosis Pulmonar/patología , Fumar/patología
20.
Rev Mal Respir ; 5(5): 511-8, 1988.
Artículo en Francés | MEDLINE | ID: mdl-3055098

RESUMEN

Modern studies undertaken to aid the understanding of the pathogenesis of pulmonary sarcoidosis have shown that the initial lesions of this disease are characterised by an accumulation of T lymphocytes and of macrophages in the alveolar structure (the alveolitis). In patients with active disease these cells are seen to be not only increased but apparently "activated". In effect, in sarcoidosis the greater part of the T lymphocytes of the lung express surface markers associated with helper/inducer phenotype and they spontaneously secrete mediators which seem to play a central role in the formation of the typical lesions of this disease: a lymphocytic alveolitis, granulomas and interstitial fibrosis. As with the T lymphocytes, the alveolar macrophages of patients suffering from active sarcoidosis appear to be activated and are important in the initiation and maintenance of the inflammatory phenomena which lead to a modification of alveolar structures which are typical of this disease. However, although the immune and inflammatory cells situated in the lung modulate the lesions in the respiratory tree, it may be reasonable to propose the hypothesis that the evaluation of the clinical state of patients with sarcoidosis might take into account the degree of the alveolitis. The parameters of this alveolitis, which may help to establish the prognosis and need for therapy in pulmonary sarcoidosis, have not yet been discovered.


Asunto(s)
Enfermedades Pulmonares/patología , Macrófagos/patología , Alveolos Pulmonares/patología , Sarcoidosis/patología , Linfocitos T/patología , Humanos , Enfermedades Pulmonares/etiología , Macrófagos/fisiología , Monitoreo Fisiológico , Neumonía/patología , Sarcoidosis/etiología , Linfocitos T/fisiología
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