scholarly journals Spectral precursors of paroxysmal phases of Stromboli

1996 ◽  
Vol 39 (2) ◽  
Author(s):  
R. Carniel ◽  
F. Iacop
Keyword(s):  
Continuous Monitoring ◽  
Energy Content ◽  
Volcanic Tremor ◽  
Energy Concentration ◽  
Stromboli Volcano ◽  
Stable States ◽  
Spectral Content ◽  
Abrupt Changes ◽  
Intense Activity ◽  
Dangerous Activity

In this work we investigate the characteristics of the seismicity at Stromboli volcano during more than two years, i.e. from 11 May 1992 to 21 August 1994. The three paroxysmal phases of 1993 mark significant changes in the Strombolian activity; nevertheless, these are not the only ones observed. In fact, the energy content, both in terms of volcanic tremor and of number of events drops to very low values after the periods of intense activity, accompanied by a change in the spectral content of the tremor. However, equally abrupt changes in the frequency content, not accompanied by evident intensity variations, can be observed some weeks after the end of the crises. The volcano seems therefore to behave like a dynamical system with many «quite stable » states with abrupt transitions between them. An interesting observation is the appearance of an energy concentration in the spectral sectors below 3 Hz before more violent eruptive episodes; although the duration of such a phenomenon is variable, it has to be investigated as a possible precursor of potentially dangerous activity of the volcano. A continuous monitoring of the spectral content of volcanic tremor on Stromboli is confirmed to be an essential tool in order to understand the behaviour of Stromboli volcano and to try to forecast its paroxysmal phases.

AN EVALUATION OF THE RELATIONSHIPS BETWEEN DIETARY PARAMETERS AND RUMEN LIQUID TURNOVER RATE

1981 ◽  
Vol 61 (1) ◽  
pp. 91-96 ◽  
Author(s):  
ESSI EVANS
Keyword(s):  
Feed Intake ◽  
Turnover Rate ◽  
Energy Content ◽  
Energy Concentration ◽  
Dietary Energy ◽  
Regression Analyses ◽  
Turnover Rates ◽  
Independent Variables ◽  
Independent Variable ◽  
Ration Composition

Data were accumulated from published sources and were combined in order to estimate the effects of level of feed intake, dietary energy concentration, energy intake level and dietary forage percentage on rumen liquid turnover rates in sheep and cattle. The effects of the dietary parameters on liquid turnover rates were estimated by regression analysis, where all possible combinations of independent variables were considered. It was found that rumen liquid turnover rates increased (P < 0.05) as feed intake increased with both sheep (r = 0.610) and cattle (r = 0.715). From multiple regression analyses it was learned that the inclusion of independent variables that were related to the physical composition of the diet along with variables for intake improved the estimation of liquid turnover rates, although the independent variable related to ration composition differed between sheep and cattle. With data from sheep experiments, elevations in the digestible energy content of the diet depressed (P < 0.05) liquid turnover rate. Based upon data from cattle, decreases in the forage portion of the diet had a similar depressing (P < 0.05) effect.

scholarly journals Neural networks and dynamical system techniques for volcanic tremor analysis

1996 ◽  
Vol 39 (2) ◽  
Author(s):  
R. Carniel
Keyword(s):  
Dynamical System ◽  
State Space ◽  
Structural Changes ◽  
Volcanic Tremor ◽  
Lag Time ◽  
State Variables ◽  
Stromboli Volcano ◽  
Structural Configuration ◽  
Experimental Time Series ◽  
Tremor Analysis

A volcano can be seen as a dynamical system, the number of state variables being its dimension N. The state is usually confined on a manifold with a lower dimension f, manifold which is characteristic of a persistent «structural configuration». A change in this manifold may be a hint that something is happening to the dynamics of the volcano, possibly leading to a paroxysmal phase. In this work the original state space of the volcano dynamical system is substituted by a pseudo state space reconstructed by the method of time-delayed coordinates, with suitably chosen lag time and embedding dimension, from experimental time series of seismic activity, i.e. volcanic tremor recorded at Stromboli volcano. The monitoring is done by a neural network which first learns the dynamics of the persistent tremor and then tries to detect structural changes in its behaviour.

scholarly journals Milk Urea Concentration in Dairy Sheep: Accounting for Dietary Energy Concentration

Animals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1118 ◽  
Author(s):  
Valeria Giovanetti ◽  
Filippo Boe ◽  
Mauro Decandia ◽  
Giovanni Cristoforo Bomboi ◽  
Alberto Stanislao Atzori ◽  
...  
Keyword(s):  
Mean Squared Error ◽  
Energy Content ◽  
High Energy ◽  
Urea Concentration ◽  
Energy Concentration ◽  
Net Energy ◽  
Dietary Energy ◽  
Dairy Sheep ◽  
Dairy Ewes ◽  
Milk Urea

In dairy sheep milk urea concentration (MUC) is highly and positively correlated with dietary crude protein (CP) content and, to a lesser extent, with protein intake. However, the effect of dietary energy and carbohydrate sources on MUC of lactating ewes is not clear. Thus, the objective of this study was to assess the effects of diets differing in energy concentration and carbohydrate sources on MUC values in lactating dairy ewes. Two experiments were conducted (experiment 1, E1, and experiment 2, E2) on Sarda ewes in mid and late lactation kept in metabolic cages for 23 d. In both experiments, homogeneous groups of five ewes were submitted to four (in E1) or three (in E2) dietary treatments, consisting of pelleted diets ranging from low energy (high-fiber diets: 1.2–1.4 Mcal of net energy for lactation (NEL)) to high energy (high-starch diets: 1.7–1.9 Mcal of NEL) contents, but with a similar CP concentration (18.4% dry matter (DM), on average). Each diet had a different main ingredient as follows: corn flakes, barley meal, beet pulp, or corn cobs in E1 and corn meal, dehydrated alfalfa, or soybean hulls in E2. Regression analysis using treatment means from both experiments showed that the best predictor of MUC (mg/100 mL) was the dietary NEL (Mcal/kg DM, MUC = 127.6 − 51.2 × NEL, R2 = 0.85, root of the mean squared error (rmse) = 4.36, p < 0.001) followed by the ratio CP/NEL (g/Mcal, MUC = −14.9 + 0.5 × CP/ NEL, R2 = 0.83, rmse = 4.63, p < 0.001). A meta-regression of an extended database on stall-fed dairy ewes, including the E1 and E2 experimental data (n = 44), confirmed the predictive value of the CP/ NEL ratio, which resulted as the best single predictor of MUC (MUC = −13.7 + 0.5 × CP/NEL, R2 = 0.93, rmse = 3.30, p < 0.001), followed by dietary CP concentration (MUC = −20.7 + 3.7 × CP, R2 = 0.82, rmse = 4.89, p < 0.001). This research highlights that dietary energy content plays a pivotal role in modulating the relationship between MUC and dietary CP concentration in dairy sheep.

Effects of season and time since defoliation on the nutritive characteristics of three irrigated perennial pasture species in northern Victoria 1. Energy, protein and fibre

1999 ◽  
Vol 39 (5) ◽  
pp. 555 ◽  
Author(s):  
C. R. Stockdale
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Crude Protein ◽  
Energy Content ◽  
Energy Concentration ◽  
Neutral Detergent Fibre ◽  
Plant Parts ◽  
Metabolisable Energy ◽  
Grazing Dairy Cows

The study reported here compared the nutritive characteristics of the 3 most common irrigated perennial pasture species grown in northern Victoria as they regrew after defoliation at various times during the year. In addition, the relative influence of changes to the proportions of morphological components and the nutritive characteristics of the individual components on the quality of whole plants was examined. The nutritive characteristics of white clover (Trifolium repens cv. Haifa), ryegrass (Lolium perenne cv. Ellet) and paspalum (Paspalum dilatatum) were examined at weekly intervals on 4 occasions during spring–autumn, 1993–94. On each occasion, pastures were defoliated with a drum mower and allowed to regrow for up to 9 weeks; defoliation dates were 24 September, 26 November, 28 January and 25 March. The variation in estimated metabolisable energy [obtained from in vitro dry matter (DM) digestibility], crude protein and detergent fibre concentrations within species was significantly (P<0.01) less than between clover and the grasses. White clover was consistently high in metabolisable energy (9.3–11.2 MJ/kg DM) and crude protein (17.7–27.7% DM), and low in neutral detergent fibre (27.8–39.8% DM) in all periods. At the other extreme, paspalum had a metabolisable energy content that peaked at 9.3 MJ/kg DM, and fell as low as 7.4 MJ/kg DM. Paspalum also had low protein (7.5–14.7% DM) and very high neutral detergent fibre (61.9–69.9% DM) concentrations. Ryegrass varied greatly in metabolisable energy concentration between the 4 periods, being high in autumn (average of 10.2 MJ/kg DM) and low in summer–autumn (average of 8.4 MJ/kg DM). Metabolisable energy apart, there were few differences in the crude protein and detergent fibre contents of ryegrass and paspalum. Perennial ryegrass is generally considered a superior feed to paspalum, but the data indicate this is not always the case under irrigation in northern Victoria. The nutritive characteristics of the plant fractions (leaf, stem, dead, inflorescence) were analysed separately to give an indication of the limits to selection by grazing cows. Differences in metabolisable energy between leaf and stem in both white clover and perennial ryegrass suggested that grazing dairy cows could consume a pasture diet which is likely to be slightly higher in energy than that in the herbage on offer. With paspalum, this is unlikely to be the case because differences in energy content between plant parts were small. However, with all species, cows should be able to consume herbage that is significantly higher in protein, and lower in detergent fibre, than that on offer because of differences in their concentrations in leaf and stem. The nutritive characteristics of morphological components of each species remained relatively constant throughout the study. Therefore, it would seem that it is the proportions of these fractions in the plant, together with severity of grazing, that will largely determine the degree of selection that can occur.

Statistical analyses and characteristics of volcanic tremor on Stromboli Volcano (Italy)

1998 ◽  
Vol 60 (2) ◽  
pp. 75-88 ◽  
Author(s):  
S. Falsaperla ◽  
H. Langer ◽  
S. Spampinato
Keyword(s):  
Volcanic Tremor ◽  
Statistical Analyses ◽  
Stromboli Volcano

scholarly journals THE EFFECTS OF BROILER LITTER AS PROTEIN SOURCE ON THE PERFORMANCE OF BUNAJI (WHITE FULANI) BULL CALVES

1996 ◽  
Vol 23 (1) ◽  
pp. 66-71
Author(s):  
M. A. BELEWU ◽  
J. A. ADENEYE
Keyword(s):  
Energy Content ◽  
Energy Concentration ◽  
Panicum Maximum ◽  
Crude Fibre ◽  
Broiler Litter ◽  
Neutral Detergent Fibre ◽  
Dietary Nitrogen ◽  
Voluntary Feed Intake ◽  
Bull Calves ◽  
Ad Libitum

Effect on Voluntary feed intake and Intensive livestock production in recent digestibility when growing cattle consuming forage were supplemented with autoclaved broiler litter (ABL) was investigated. Four, 8-11 months old Bunaji bull calves (82.20kg mean initial BW) in a 4x4 Latin squuare with 21-d periods consuming Panicum Maximum hay ad libitum were randomly alloted to treatments. Concentrate supplement treatments with A (Control, 20 ABL), B (20%), C (40%) and (60%)ABL levels respectively. Calves consumed an average of 1882.25g DM, 165, CP from the sole hay ration. As ABL inclusion increased in the concentrated diets, mean intake crude protein (CP), crude fibre (CF), detergent fibre (ADF), neutral detergent fibre (CF), and detergent fibre (ADF), neutral detergent fibre (NDF) and cellulose increased EE decreased significantly (P<0.01). quality, depending largely on type of bedding The digestibilities of the DM, CP, CF, ADF, NDF and cellulose of ration A that contained the highest CW (98%) and the least CP (5.14%) where energy content is low (FAO, 1980). Reduction significantly lower (P < 0.01) than those of ABL of chergy content resulting from the based rations B to D. gain was  greatest (P<0.05) for rations D. Gain:DM intake was greater with ABL than without (0.07,  0.40.0.16 and 0.17 for control A, B, C, and D diets The MFN: FN ratio declined as  dietary nitrogen level increased. The results. emphasised the need to supplement the feeding The digestible energy concentration of the of Bunaji cattle with a concentrate diet that Insight simply consist of a combination of roughage (Fontenot and Jurubescu, cassava wastes meal (CWM) and autoclaved broiler litter (ABL), the best of which was shown in this study to be 60% ABL and 38% CWM offered ad Libitum.

scholarly journals Volcanic Tremor of Mt. Etna (Italy) Recorded by NEMO-SN1 Seafloor Observatory: A New Perspective on Volcanic Eruptions Monitoring

Geosciences ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 115
Author(s):  
Tiziana Sgroi ◽  
Giuseppe Di Grazia ◽  
Paolo Favali
Keyword(s):  
Gravity Waves ◽  
Volcanic Tremor ◽  
Volcanic Eruptions ◽  
Seismic Signal ◽  
High Amplitude ◽  
Sea Waves ◽  
Spectral Content ◽  
Mt Etna ◽  
New Perspective ◽  
Seafloor Observatory

The NEMO-SN1 seafloor observatory, located 2100 m below sea level and about 40 km from Mt. Etna volcano, normally records a background seismic signal called oceanographic noise. This signal is characterized by high amplitude increases, lasting up to a few days, and by two typical 0.1 and 0.3 Hz frequencies in its spectrum. Particle motion analysis shows a strong E-W directivity, coinciding with the direction of sea waves; gravity waves induced by local winds are considered the main source of oceanographic noise. During the deployment of NEMO-SN1, the vigorous 2002–2003 Mt. Etna eruption occurred. High-amplitude background signals were recorded during the explosive episodes accompanying the eruption. The spectral content of this signal ranges from 0.1 to 4 Hz, with the most powerful signal in the 0.5–2 Hz band, typical of an Etna volcanic tremor. The tremor recorded by NEMO-SN1 shows a strong NW-SE directivity towards the volcano. Since the receiver is underwater, we inferred the presence of a circulation of magmatic fluids extended under the seafloor. This process is able to generate a signal strong enough to be recorded by the NEMO-SN1 seafloor observatory that hides frequencies linked to the oceanographic noise, permitting the offshore monitoring of the volcanic activity of Mt. Etna.

Body composition of young sheep and goats determined by the tritium dilution technique

1993 ◽  
Vol 121 (3) ◽  
pp. 399-408 ◽  
Author(s):  
R. W. Benjamin ◽  
R. Koenig ◽  
K. Becker
Keyword(s):  
Body Composition ◽  
Chemical Composition ◽  
Energy Content ◽  
Tritiated Water ◽  
Component Composition ◽  
The Body ◽  
Energy Concentration ◽  
Sheep And Goats ◽  
Body Components ◽  
Similar Body

SUMMARYTen young crossbred Finnish Landrace sheep and eleven young crossbred Damascus goats with liveweights ranging from 14 to 50 kg and of different ages and body condition, were used to develop equations to predict the body composition (chemical) in the intact body and dressed carcass of young sheep and goats. After injection with tritiated water, the animals were slaughtered and their carcasses partitioned into anatomical body components which were each analysed for chemical composition (water, fat, protein, ash) and energy content. From these components, the energy content and chemical composition of the intact bodies were calculated by summation. Apart from organ and gut fat, the two species had a similar body component composition. Goat intact bodies were more hydrated and had less fat, but were similar to sheep in protein and ash content. The energy concentration in their body components was also similar, but goats had a lower energy concentration in their intact bodies. Total body water, energy content and dressed carcass were predicted accurately by the derived equations, but fat, protein and ash were predicted with less precision.

Dietary energy content and floor space relationships for optimal growth and efficiency of broilers

1974 ◽  
Vol 14 (67) ◽  
pp. 141 ◽  
Author(s):  
WJ Yule
Keyword(s):  
Energy Content ◽  
Stocking Density ◽  
Optimal Growth ◽  
Metabolizable Energy ◽  
Energy Concentration ◽  
Total Output ◽  
Controlled Environment ◽  
Dietary Energy ◽  
Fixed Size ◽  
Floor Space

Commercial broilers, kept in small, fixed-size pens, were allowed 310, 370, or 460 cm2 of floor space per bird started at one day of age, in a windowless controlled environment house. At each stocking density birds were offered diets with 12.5, 12.9, or 13.4 MJ kg-1 of metabolizable energy from 41 to 64 days of age. Male and female broilers grew more slowly (P < 0.05) when offered the lowest energy diet. They were heavier (P < 0.05) when allowed 460cm2 of floor space per bird. Total output on the basis of liveweight produced per unit of floor space over 64 days of age was largest in the most densely stocked pens. Optimal dietary metabolizable energy concentration was approximately 12.9 MJ kg-1; however, reasons for varying this recommendation are discussed.

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