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1.
Nat Commun ; 12(1): 1683, 2021 Mar 16.
Article in English | MEDLINE | ID: mdl-33727536

ABSTRACT

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.
J Anim Sci ; 76(5): 1273-9, 1998 May.
Article in English | MEDLINE | ID: mdl-9621933

ABSTRACT

We tested the efficacy of an estrus control system designed to provide optimal control of follicular development. In Exp. 1, postpartum cows (n = 133) and yearling heifers (n = 57) were fed either .5 mg x female(-1) x d(-1) of melengestrol acetate (MGA) or the carrier for MGA from d -13 to d 0 (d 0 = last day of MGA feeding). All females received 25 mg of PGF2alpha (i.m.) on d -13 and 0. On d -6, cows and heifers fed MGA were administered an i.m. injection of progesterone (200 mg; MGA/P4), and those fed the corn carrier (2XPGF2alpha) received no progesterone. Beginning on d 1, females were bred by AI from d 1 to at least d 5. During the estrus synchronization period (d 1 to d 5), more (P < .05) postpartum cows were observed in estrus (70.1 vs 42.4%), the timing of estrus was more (P < .05) precise, conception rate was similar, and pregnancy rate was higher (P < .05) in the MGA/P4 than in the 2XPGF2alpha treatment. More (P < .05) cows that were anestrous at the beginning of the breeding season were in estrus during the synchronization period in the MGA/P4 (55.8%) than in the 2XPGF2alpha (28.6%) treatment. In heifers, estrus was synchronized in over 90% of females, and neither conception nor pregnancy rate during the synchronization period differed between treatments. In Exp. 2, postpartum cows (n = 122) and heifers (n = 84) received treatments (MGA/P4 or 2XPGF2alpha) as described for Exp. 1 with one exception. In the MGA/ P4 treatment, progesterone was administered on d -7 rather than d -6. Females were bred by AI from d 1 to 5. The estrus response and conception rate during the synchronization period did not differ between treatments for either cows or heifers. We conclude that the progestin-based estrous synchronization system used in this study effectively synchronized an estrus of normal fertility in cyclic cows and induced a majority of anestrous cows to reinitiate estrous cycles.


Subject(s)
Cattle/physiology , Dinoprost/pharmacology , Estrus Synchronization/drug effects , Melengestrol Acetate/pharmacology , Progesterone Congeners/pharmacology , Progesterone/pharmacology , Administration, Oral , Animal Feed , Animals , Dietary Supplements , Dinoprost/administration & dosage , Female , Fertilization/drug effects , Injections, Intramuscular/veterinary , Insemination, Artificial/veterinary , Melengestrol Acetate/administration & dosage , Postpartum Period/drug effects , Pregnancy , Pregnancy Rate , Progesterone/administration & dosage , Progesterone/blood , Progesterone Congeners/administration & dosage
3.
Neurophysiol Clin ; 25(3): 158-66, 1995.
Article in English | MEDLINE | ID: mdl-8524210

ABSTRACT

There are few reports in the literature dealing with the association between mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) and epilepsia partialis continua (EPC) in children. We report the case of a child presenting with numerous stroke-like episodes associated with EPC which, despite therapy, were not controlled and aggravated the clinical condition of our patient. We present the neuroradiological, biochemical, genetic and muscle biopsy findings, and EEG characteristics, with attention to polygraphic recordings which were done during wake and sleep periods. We consider the correlation with other possible etiological factors relating to EPC and in particular coinvolvement of the basal ganglia as a cause of EPC in our patient.


Subject(s)
Epilepsies, Partial/physiopathology , MELAS Syndrome/physiopathology , Child, Preschool , Disease Progression , Electroencephalography , Fatal Outcome , Humans , Male
4.
Acta Eur Fertil ; 25(5): 283-9, 1994.
Article in English | MEDLINE | ID: mdl-7660715

ABSTRACT

The semen of the male partners of 37 infertile couples was analyzed with the use of the HTM-S Motility Analyzer (HTM-S MA). For each sample it was thus possible to assess the Total Concentration (TC), the Motile Cell Population Concentration (MCPC), the Progressive Cell Population Concentration (PCPC), the Average Path Velocity (VAP), the Straight Line Velocity (VSL), the Curvilinear Velocity (VCL), the Straightness (STR), the Linearity (LIN), the Lateral Head Displacement (ALH) and the Head Size (HS). The same parameters were then measured on the same semen after treatment with the Pellet Swim-up (PSu) and following Centrifugation on reduced-volume Discontinuous Percoll gradient (mini-CDPG). There was a significant difference in the TC (51.63 M/ml +/- 43.99 in the untreated ejaculate, 11.48 M/ml +/- 9.66 after PSu, 7.94 M/ml +/- 7.3 after mini-CDPG; chi r2 = 50.392, p < 0.05), in the MCPC (20.95 M/ml +/- 26.29 in the untreated ejaculate, 3.79 M/ml +/- 4.26 after PSu, and 2.74 M/ml +/- 3.73 after mini-CDPG; chi r2 = 33.55, p < 0.05), and in the PCPC (7.8 M/ml +/- 12.87 in the untreated ejaculate, 1.81 M/ml +/- 2.36 after PSu, and 1.28 M/ml +/- 1.73 after min-CDPG; chi r2 = 6.38; p < 0.05). The overall comparison between the couples showed a significant difference in the MCPC after PSu and after mini-CDPG (z = -2.09, p < 0.05) whereas no significant difference was found in the comparison off the results of either the TC after PSu and after mini-CDPG (z = -1.9; NS), or of the PCPC after PSu and after mini-CDPG (z = -1.68; NS).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Image Processing, Computer-Assisted/standards , Semen/physiology , Sperm Motility/physiology , Adult , Centrifugation, Density Gradient , Humans , Infertility, Male/physiopathology , Male , Sperm Count , Spermatozoa/cytology , Spermatozoa/physiology
6.
Pediatr Med Chir ; 6(6): 791-3, 1984.
Article in Italian | MEDLINE | ID: mdl-6545592

ABSTRACT

Twelve cases of duodenal ulcer were studied in children, 11 male and 1 female (mean age 10 +/- 2.7 years) (mean weight 30 +/- 3.7 Kg.) (Group 1). All were submitted to x-ray examination and/or digestive endoscopy. Twenty healty children, matched by weight, age and sex were chosen as controls (Group 2). All children underwent a standardizet protein meal to evaluate serum gastrin and pepsinogen I response and the pentagastrin test for gastric acid secretion. The serum gastrin levels were found to be without significative differences in the two groups, both in the fasting state (Group 1: 77 +/- 16 pg/ml vs. Group 2: 58 +/- 12 pg/ml) and after food stimulation (Group 1: 110 +/- 22 pg/ml vs. Group 2: 88 +/- 47 pg/ml), whereas the basal serum pepsinogen I (Group 1: 74 +/- 10 ng/ml vs. Group 2: 43 +/- 1.8 ng/ml) and after meal (Group 1: 83 +/- 14 ng/ml vs. Group 2: 49 +/- 2.1 ng/ml) values were statistically higher in the duodenal ulcer group (p less than 0.01). The pentagastrin test showed a statistically difference in MAO (Group 1: 0.370 +/- 0.10 mmol/H+/hr./Kg. vs. Group 2: 0.210 +/- 0.11 mmol/H+/hr./Kg. - p less than 0.001) and PAO (Group 1: 0.480 +/- 0.13 mmol/H+/hr./Kg. vs. Group 2: 0.351 +/- 0.12 mmol/H+/hr./Kg. - p less than 0.005) between the groups. The results confirm that elevated gastric acid response is already present in duodenal ulcer of children and seems to be its cause rather than its consequence. Our finding of an already reported family histories of the disease, further support an inherited basis for duodenal ulcer in children.


Subject(s)
Duodenal Ulcer/metabolism , Gastric Acid/metabolism , Adolescent , Child , Female , Gastrins/blood , Humans , Male , Pepsinogens/blood
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