31 research outputs found
Nutrient management planning on Irish dairy farms
End of Project ReportThe objective of the work undertaken was to investigate nutrient use
on intensive dairy farms. A survey of 12 dairy farms was undertaken
in 1997 to determine nutrient management practices. These were
compared with current nutrient advice and recommended practices.
Data recording was completed by the farmer and supplemented by regular
farm visits to assist with and validate the process.
The mean farm size was 64.8 ha with an average of 128 cows and an
annual milk yield per cow of 5594 kg. The mean stocking rate was
2.58 Livestock Units/ha. Dairy cows accounted for highest proportion
of the total livestock with most of the younger stock consisting of dairy
replacements.
Approximately 80% of soil P levels were greater than 6 mg/l while 67%
of soils had soil K levels in excess of 100 mg/l. The mean soil P and K
levels on the grazing and silage areas were 11 and 128 mg/l, 12 and
117 mg/l, respectively.
The mean farm nutrient balance (inputs - outputs) established an
annual surplus of N, P and K of 304, 18 and 53 kg/ha, respectively.
The adoption of nutrient management plans instead of current practice
would reduce N, P and K inputs on average by 44, 13 and 24
kg/ha, respectively. The use of the Teagasc revised P nutrient advice
would further reduce the P input requirements by 2 kg/ha. On average
the farms had 90% of the 16 week slurry storage capacity.
Approximately 14, 42, 14 and 31% of the slurry was applied in spring,
summer, autumn and winter, respectively. In all cases there was significant
between farm variability.
The soil P fertility on the survey farms is skewed towards index 3 and
4 when compared with the average for all samples received at Johnstown
Castle. There is no agronomic advantage in terms of crop or animal
production for soils to have P levels in excess 10 mg/l. This result
indicates that P inputs to farms of this type can be reduced in many
cases without prejudicing production potential. The nutrient balance
conducted highlighted the extent of the nutrient surpluses and the between farm variability. The data suggest that there is not a serious
nutrient surplus on the survey farms, which would require the use of
additional off-farm land for slurry recycling, as obtains on pig and
poultry farms. The study also indicates that although farm unit cost
savings may be small in adopting nutrient management planning, overall
farm savings may be significant. For example on the survey farms,
savings of up to £2,000 can be achieved apart from the obvious positive
environmental impact
Why Are Clinically Indicated, But Lower-Risk, Patients Less Likely to Receive Implantable Cardioverter-Defibrillator and Cardiac Resynchronization Therapy?*
Challenges and Outcomes of Posterior Wall Isolation for Ablation of Atrial Fibrillation
BACKGROUND: The left atrial posterior wall (PW) often contains sites required for maintenance of atrial fibrillation (AF). Electrical isolation of the PW is an important feature of all open surgeries for AF. This study assessed the ability of current ablation techniques to achieve PW isolation (PWI) and its effect on recurrent AF.
METHODS AND RESULTS: Fifty-seven consecutive patients with persistent or high-burden paroxysmal AF underwent catheter ablation, which was performed using an endocardial-only (30) or a hybrid endocardial-epicardial procedure (27). The catheter ablation lesion set included pulmonary vein antral isolation and a box lesion on the PW (roof and posterior lines). Success in creating the box lesion was assessed as electrical silence of the PW (voltage <0.1Â mV) and exit block in the PW with electrical capture. Cox proportional hazards models were used for analysis of AF recurrence. PWI was achieved in 21 patients (36.8%), more often in patients undergoing hybrid ablation than endocardial ablation alone (51.9% versus 23.3%, P=0.05). Twelve patients underwent redo ablation. Five of 12 had a successful procedural PWI, but all had PW reconnection at the redo procedure. Over a median follow-up of 302Â days, 56.1% of the patients were free of atrial arrhythmias. No parameter including procedural PWI was a statistically significant predictor of recurrent atrial arrhythmias.
CONCLUSIONS: PWI during catheter ablation for AF is difficult to achieve, especially with endocardial ablation alone. Procedural achievement of PWI in this group of patients was not associated with a reduction in recurrent atrial arrhythmias, but reconnection of the PW was common
Exploring links between greenspace and sudden unexpected death: A spatial analysis
Greenspace has been increasingly recognized as having numerous health benefits. However, its effects are unknown concerning sudden unexpected death (SUD), commonly referred to as sudden cardiac death, which constitutes a large proportion of mortality in the United States. Because greenspace can promote physical activity, reduce stress and buffer air pollutants, it may have beneficial effects for people at risk of SUD, such as those with heart disease, hypertension, and diabetes mellitus. Using several spatial techniques, this study explored the relationship between SUD and greenspace. We adjudicated 396 SUD cases that occurred from March 2013 to February 2015 among reports from emergency medical services (EMS) that attended out-of-hospital deaths in Wake County (central North Carolina, USA). We measured multiple greenspace metrics in each census tract, including the percentages of forest, grassland, average tree canopy, tree canopy diversity, near-road tree canopy and greenway density. The associations between SUD incidence and these greenspace metrics were examined using Poisson regression (non-spatial) and Bayesian spatial models. The results from both models indicated that SUD incidence was inversely associated with both greenway density (adjusted risk ratio [RR] = 0.82, 95% credible/ confidence interval [CI]: 0.69–0.97) and the percentage of forest (adjusted RR = 0.90, 95% CI: 0.81–0.99). These results suggest that increases in greenway density by 1 km/km2 and in forest by 10% were associated with a decrease in SUD risk of 18% and 10%, respectively. The inverse relationship was not observed between SUD incidence and other metrics, including grassland, average tree canopy, near-road tree canopy and tree canopy diversity. This study implies that greenspace, specifically greenways and forest, may have beneficial effects for people at risk of SUD. Further studies are needed to investigate potential causal relationships between greenspace and SUD, and potential mechanisms such as promoting physical activity and reducing stress
Electrocardiographic Criteria Still Useful for Mapping of Idiopathic Right Ventricular Tachycardia
Recommended from our members
JNDS, Volume 25, Number 2
Article exploring the reasons why near-death experiences may not occur during induced cardiac arrest
Nutrient management planning on Irish dairy farms
End of Project ReportThe objective of the work undertaken was to investigate nutrient use
on intensive dairy farms. A survey of 12 dairy farms was undertaken
in 1997 to determine nutrient management practices. These were
compared with current nutrient advice and recommended practices.
Data recording was completed by the farmer and supplemented by regular
farm visits to assist with and validate the process.
The mean farm size was 64.8 ha with an average of 128 cows and an
annual milk yield per cow of 5594 kg. The mean stocking rate was
2.58 Livestock Units/ha. Dairy cows accounted for highest proportion
of the total livestock with most of the younger stock consisting of dairy
replacements.
Approximately 80% of soil P levels were greater than 6 mg/l while 67%
of soils had soil K levels in excess of 100 mg/l. The mean soil P and K
levels on the grazing and silage areas were 11 and 128 mg/l, 12 and
117 mg/l, respectively.
The mean farm nutrient balance (inputs - outputs) established an
annual surplus of N, P and K of 304, 18 and 53 kg/ha, respectively.
The adoption of nutrient management plans instead of current practice
would reduce N, P and K inputs on average by 44, 13 and 24
kg/ha, respectively. The use of the Teagasc revised P nutrient advice
would further reduce the P input requirements by 2 kg/ha. On average
the farms had 90% of the 16 week slurry storage capacity.
Approximately 14, 42, 14 and 31% of the slurry was applied in spring,
summer, autumn and winter, respectively. In all cases there was significant
between farm variability.
The soil P fertility on the survey farms is skewed towards index 3 and
4 when compared with the average for all samples received at Johnstown
Castle. There is no agronomic advantage in terms of crop or animal
production for soils to have P levels in excess 10 mg/l. This result
indicates that P inputs to farms of this type can be reduced in many
cases without prejudicing production potential. The nutrient balance
conducted highlighted the extent of the nutrient surpluses and the between farm variability. The data suggest that there is not a serious
nutrient surplus on the survey farms, which would require the use of
additional off-farm land for slurry recycling, as obtains on pig and
poultry farms. The study also indicates that although farm unit cost
savings may be small in adopting nutrient management planning, overall
farm savings may be significant. For example on the survey farms,
savings of up to £2,000 can be achieved apart from the obvious positive
environmental impact