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Cereal grains are often subjected to physical processing before being fed to equids. However, little information is available on how physical processing of cereals affects degradation dynamics in equids. This experiment examines the effect of two physical processing methods (micronisation and extrusion) on in situ degradation of barley in the caecum of ponies
Three caecally fistulated mature Welsh-cross pony geldings (approx. LW 270kg) were offered ad libitum grass hay plus minerals. Incubation bags (monofilament polyester 6.5 x 20cm, 41μm pores, 16mg/cm2 sample size) containing either unprocessed barley (UB), micronised barley (MB) or extruded barley (EB) were incubated in the caecum for fixed times according to both a forward (0, 2, 4, 6, 12, 8, 24, 48h) and reverse (48, 24, 8, 4, 12, 6, 2, 0h) incubation sequence. For each feedstuff residues from each time were bulked within pony and across incubation sequence for subsequent analysis of dry matter (DM) and starch (STC). Degradation profiles were fitted to the DM and STC disappearance data according to Ørskov and McDonald (1979).
X-ray computed tomography (CT) measurements of live sheep have been used to predict carcass composition very accurately (Macfarlane et al., 2006). The utilisation of spiral CT scans (SCTS) for quantifying muscle volumes and weights, using automatic image analysis procedures has also been shown to be very accurate in sheep (Navajas et al., 2006). Although the limiting size of the CT gantry prevents CT scanning of live beef cattle, beef primal joints are small enough to be scanned. Hence, SCTS could be used to quantify beef carcass composition, and provide valuable information for breeding programmes including composition faster than by anatomical dissection. The objective of this study was to develop a CT image analysis procedure to assess fat, muscle and bone weights of beef carcasses and to evaluate its accuracy.
Livestock farming is a traditional and important contributor to the rural economy in the hills and uplands of the UK. However, significant areas of the uplands have seen a decline in the condition of heath and mire habitats and the loss of dwarf shrubs as a result of over-grazing. Attempts to halt the decline and improve the condition of upland heath and mire habitats have been undertaken by the introduction of agri-environment schemes. In the main, such schemes rely on the reduction of sheep numbers. However, recent Defra funded research (LS1508) has indicated that this can result in dominance by competitive and/or unpalatable species such as purple moor-grass (Molinia caerulea ) or mat-grass (Nardus stricta ), leading in time to a reduction in the physical and financial performance of the flock. The objective of this study is to assess the impact of cattle grazing on Nardus stricta dominated pasture on sheep and cattle performance. It is being carried out as part of a wider project to determine environmentally sustainable and economically viable grazing systems for heather moorland.
Little information is available on how physical processing of cereals affects crude protein (CP) degradation dynamics in equines. In two experiments the effects of two physical processing methods (micronisation and extrusion) on in situ degradation of CP in barley, maize and peas in the caecum of ponies were investigated.
In experiment 1, three caecally-fistulated mature Welsh-cross pony geldings (approx. LW 270kg) were used whilst two of these ponies were used in experiment 2. In both experiments ponies were offered ad libitum grass hay plus minerals. Incubation bags (monofilament polyester, 6.5 x 20cm, 41μm pores, 16mg/cm2 sample size) contained either unprocessed barley (UB), micronised barley (MB) or extruded barley (EB) (experiment 1) and either unprocessed maize (UM), micronised maize (MM), extruded maize (EM), unprocessed peas (UP), micronised peas (MP) or extruded peas (EP) (experiment 2).
A wide variety of starch based feeds are available for inclusion in equine diets. These feeds may be subjected to physical processing (micronisation or extrusion) prior to inclusion. This experiment evaluates a range of starch based feedstuffs using an in vitro batch culture technique.
A total of 15 feedstuffs were incubated in vitro with an inocula prepared from freshly voided faeces which was collected from six ponies fed grass hay ad libitum. The feeds were five starch based feedstuffs; i.e: maize (M), peas (P), wheat (W), naked oats (NO) or barley (Ba) in one of three physically processed forms i.e: unprocessed (Unp), micronised (Mic) or extruded (Ext). All feeds were ground through a 1.0mm screen prior to incubation. Cumulative gas production (GP) was measured using the pressure transducer technique of Theodorou et al (1994) throughout a 72 h incubation period.
Previous work has shown that the mobile bag technique (MBT) can be used to study the dynamics of digestive processes in the whole tract of ponies (Hyslop et al, 1998). This experiment further develops the MBT as a method to study feed degradation dynamics over time in the pre-caecal segment of the digestive tract of ponies.
Two caecally-fistulated mature Welsh-cross pony geldings (LW 270kg) were offered 4kg of dry matter (DM) per day of a 1:3 rolled barley:hay cube mix plus minerals, in 2 equal meals per day at 09:00 and 17:00h. Grass hay was also offered ad libitum between 17:00 and 09:00h. Two sizes of mobile bag (6 x 1 cm Ø-large and 4 x 1 cm Ø- small) made from monofilament polyester with a 7 μm pore size were used.
Processed cereals are used routinely in diets for equines but little information is available on how physical processing affects the digestibility of cereals in equines. This study examines the effects of three physical processing methods (rolling, micronisation and extrusion) on the in vivo apparent digestibility of barley fed to ponies.
Three mature caecally-fistulated Welsh-cross pony geldings, (LW 284kg ± 3.8kg) were used in a 3 x 4 incomplete latin square changeover design experiment consisting of four 21 day periods. Each period comprised a sixteen day adaptation phase and a five day recording phase when apparent digestibility in vivo was determined. Ponies were offered 4kg dry matter (DM) per day of either 100% hay cubes (HC) or one of three diets consisting of a 50:50 barley:hay cubes mix. The barley in the mixed diets was either rolled barley (RB), micronised barley (MB) or extruded barley (EB). Diets were offered in 2 equal meals per day fed at 09:00 and 17:00 hours respectively.
Maize and peas that have undergone physical processing are used routinely in cereal mixes for equines. However, little information is available on how physical processing of maize and peas affects degradation dynamics in equines. This experiment examines the effect of two physical processing methods (micronisation and extrusion) on in situ degradation of maize and peas in the caecum of ponies
Two caecally-fistulated mature Welsh-cross pony geldings (approx. LW 270kg) were offered ad libitum grass hay plus minerals. Incubation bags (monofilament polyester 6.5 x 20cm, 41? m pores, 16mg/cm2 sample size) containing either unprocessed maize (UM), micronised maize (MM), extruded maize (EM), unprocessed peas (UP), micronised peas (MP) or extruded peas (EP) were incubated in the caecum for fixed times according to both a forward (0, 2, 4, 6, 12, 8, 24, 48h) and reverse (48, 24, 8, 4, 12, 6, 2, 0h) incubation sequence. For each feedstuff residues from each time were bulked within pony and across incubation sequence for subsequent analysis of dry matter (DM) and starch (STC).
Estimates of digesta passage through specific segments of the alimentary tract are a vital component of modelling approaches which attempt to quantitatively partition digestive processes in equines. This study reports results from three studies where digesta passage of Chromium (Cr) mordanted feeds was determined in the caecum of ponies.
Caecal outflow rates were determined during three in vivo apparent digestibility studies conducted using three caecally-fistulated ponies as described by Moore-Colyer et al, (1999) for studies 1 and 2; and McLean et al, (1999) for study 3. Pony basal diets consisted of unmolassed sugar beet pulp (USBP), hay cubes (HC) or a 2:1 mix of oat hulls:naked oats (OHNO) in study 1; a 1:1 mix of USBP:HC (USHC) in study 2 and either 100% HC or one of 3 diets consisting of a 1:1 HC:barley mix where the barley was either rolled (RBHC), micronised (MBHC) or extruded (EBHC) in study 3.
Particle size (PS) may be reduced when feeds are ground through small screen sizes leading to increased losses from artificial fibre bags during in situ or mobile bag experiments in equines. Smaller PS may also alter the water holding capacity (WHC) of feeds which in turn may alter bag transit times during mobile bag experiments. This study examines PS and WHC in a range of starch based equine feedstuffs ground through two screen sizes.
Five feedstuffs (F) were used ie: barley (B), maize (M), peas (P), wheat (W) and naked oats (NO). Feedstuffs were subjected to three types of physical pre-processing (Pr) ie: unprocessed (Un), micronised (Mi) or extruded (Ex) and then ground through either a 1.0 or 0.5 mm screen size (SS). For PS analysis a 25g sample of each feedstuff was sieved through a stack of 11 sieves ranging in pore diameter between 45 μm and 2 mm using a mechanical shaker for 20 min.
In vitro techniques have been developed to study the fermentation kinetics of a wide range of animal feedstuffs but relatively few studies have been conducted specifically with purified feed constituents. This study uses the pressure transducer technique of Theodorou et al (1994) to record cumulative gas production (GP) when six purified starch sources were incubated in vitro.
Three replicates of six commercially available purified (98%) starch sources were incubated in vitro with an inoculum prepared from freshly voided faeces collected from six ponies fed hay ad libitum. The starches were a purified wheat starch (ABRA), four purified wheat starches that had been chemically modified with sodium tri-metaphosphate (V1, V21, V33 & V65) and a purified pea starch (PEA). GP was measured using the pressure transducer technique throughout a 72 h incubation period. At the end of the incubation period DM loss (DML) in vitro was determined by filtration.
Introduction: Point of care ultrasound (US) is a key adjunct in the management of trauma patients, in the form of the extended focused assessment with sonography in trauma (E-FAST) scan. This study assessed the impact of adding an edus2 ultrasound simulator on the diagnostic capabilities of resident and attending physicians participating in simulated trauma scenarios. Methods: 12 residents and 20 attending physicians participated in 114 trauma simulations utilizing a Laerdal 3G mannequin. Participants generated a ranked differential diagnosis list after a standard assessment, and again after completing a simulated US scan for each scenario. We compared reports to determine if US improved diagnostic performance over a physical exam alone. Standard statistical tests (χ2 and Student t tests) were performed. The research team was independent of the edus2 designers. Results: Primary diagnosis improved significantly from 53 (46%) to 97 (85%) correct diagnoses with the addition of simulated US (χ2=37.7, 1df; p=<0.0001). Of the 61 scenarios where an incorrect top ranked diagnosis was given, 51 (84%) improved following US. Participants were assigned a score from 1 to 5 based on where the correct diagnosis was ranked, with a 5 indicating a correct primary diagnosis. Median scores significantly increased from 3.8 (IQR 3, 4.9) to 5 (IQR 4.7, 5; W=219, p<0.0001).Participants were significantly more confident in their diagnoses after using the US simulator, as shown by the increase in their mean confidence in the correct diagnosis from 53.1% (SD 22.8) to 83.5% (SD 19.1; t=9.0; p<0.0001)Additionally, participants significantly narrowed their differential diagnosis lists from an initial medium count of 3.5 (IQR 2.9, 4.4) possible diagnoses to 2.4 (IQR 1.9, 3; W=-378, p<0.0001) following US. The performance of residents was compared to that of attending physicians for each of the above analyses. No differences in performance were detected. Conclusion: This study showed that the addition of ultrasound to simulated trauma scenarios improved the diagnostic capabilities of resident and attending physicians. Specifically, participants improved in diagnostic accuracy, diagnostic confidence, and diagnostic precision. Additionally, we have shown that the edus2 simulator can be integrated into high fidelity simulation in a way that improves diagnostic performance.
A new approach is proposed to analyze Bremsstrahlung X-rays that are emitted from laser-produced plasmas (LPP) and are measured by a stack type spectrometer. This new method is based on a spectral tomographic reconstruction concept with the variational principle for optimization, without referring to the electron energy distribution of a plasma. This approach is applied to the analysis of some experimental data obtained at a few major laser facilities to demonstrate the applicability of the method. Slope temperatures of X-rays from LPP are determined with a two-temperature model, showing different spectral characteristics of X-rays depending on laser properties used in the experiments.
The passage of shock waves and ejected matter through the solar corona can produce type II and type IV radio bursts. This paper reviews the observations of these types of bursts and their interpretation, with particular emphasis on recent work.
Of the metre-wavelength solar radio bursts which have been recognized, those of type II are characterized by the most complex set of spectral features. Apparently acceptable explanations have now been put forward for most of these features. However, not all these explanations can be considered to be established. In particular the phenomenon of band splitting has been explained in different ways by Sturrock, by Tidman et al., by Zheleznyakov and Zaitsev. However, the theories of Sturrock and Tidman apparently require magnetic fields so strong as to preclude the formation of a magnetohydrodynamic shock wave by a disturbance moving at the velocity (<~ 1000 km/s) attributed to type II bursts. The same problem is encountered in other earlier theories of band splitting involving magnetic effects. The other theory does not involve the magnetic field strength. However, the details of this theory do not appear to have been properly worked out as yet.
With a number of important exceptions associated with transitory flare activity, most persistent sources of solar radio emission observed to date with the 80 MHz Culgoora radioheliograph have been stable in position over periods of tens of minutes or hours even though they fluctuated greatly in intensity. During several hours on 1968 November 11, however, we observed some interesting activity which showed frequent changes in the position of a source.
For a number of years the occurrence of isolated groups of apparently related type III bursts has been recognized as a common feature of the dynamic spectral records of solar radio emission at metre wavelengths. Interferometer observations supported the simple hypothesis that bursts of a group were usually located in the same position. In this note we report 80 MHz observations made with the Culgoora radioheliograph which show that although the sources of the bursts in a group tend to overlap one another, their centroids may show marked scatter and that their distribution tends to be along narrow lanes across the solar disk. Since the 80 MHz sources occur at heights (≳ 0.6 R⊙) near or above the plasma level, these lanes doubtless reflect some structural feature of the outer corona.
The outstanding feature of the last triennium was most certainly the abrupt generalisation of the use of array detectors, particularly CCDs (charge coupled devices). The latter pervade all subdivisions of instrumental astronomy. The gains achieved by their high quantum efficiency, their stability, their capability of delivering immediately recordable signals which can be processed by appropriate computational means, have been the cause of spectacular progress regarding the photometric precision of weak signal measurements.