The effect of smoking on the severity of mechanisms of acute exacerbations of COPD

COPD (Chronic Obstructive Pulmonary Disease) worldwide has a prevalence of 10% in men and 8.5% in women. Exacerbations of COPD account for approximately 10% of all acute medical admissions. Projected prevalence figures suggest that by 2020 COPD will be the third leading cause of mortality worldwide thus imposing a significant burden on healthcare resources in the future. Acute exacerbations are not only responsible for a decline in the patient’s quality of life, but have a major socioeconomic impact. Following a pilot study that showed current smokers recover lung function much more slowly from their exacerbation than ex smokers, I initiated a properly powered prospective study to investigate the difference between the two groups.A total of 58 patients admitted with acute infectious exacerbations of COPD were recruited to the study to determine the effect of smoking status on their exacerbation. Throughout the admission lung function was measured. Sputum was cultured for bacteria, and PCR used to detect viral infection. Blood and sputum cells were analyzed by flow cytometry. Serum was collected for CRP levels.Ex-smokers recovered significantly more quickly than current smokers in all spirometric parameters (P<0.01), and were discharged sooner (mean 3.08 vs 5.59 days, P<0.001). Sputum culture was positive for more pathogenic bacteria in current smokers, especially H. influenzae, which was associated with a significantly higher CRP rise (p<0.05) than any other organism. CD8+ T cells predominated in the sputum of ex-smokers while CD4+ T cells were the dominant cell type in current smokers (p<0.01).Current smoking is a risk factor for more severe exacerbations, delayed recovery and prolonged hospitalization. This may result from a variety of factors including bacterial, immune mediated responses and systemic inflammation

Helicopter roll control effectiveness criteria program summary

A study of helicopter roll control effectiveness is summarized for the purpose of defining military helicopter handling qualities requirements. The study is based on an analysis of pilot-in-the-loop task performance of several basic maneuvers. This is extended by a series of piloted simulations using the NASA Ames Vertical Motion Simulator and selected flight data. The main results cover roll control power and short-term response characteristics. In general the handling qualities requirements recommended are set in conjunction with desired levels of flight task and maneuver response which can be directly observed in actual flight. An important aspect of this, however, is that vehicle handling qualities need to be set with regard to some quantitative aspect of mission performance. Specific examples of how this can be accomplished include a lateral unmask/remask maneuver in the presence of a threat and an air tracking maneuver which recognizes the kill probability enhancement connected with decreasing the range to the target. Conclusions and recommendations address not only the handling qualities recommendations, but also the general use of flight simulators and the dependence of mission performance on handling qualities

Using near-infrared reflectance spectroscopy to predict the digestible protein and digestible energy values of diets when fed to barramundi, Lates calcarifer

This study examined the potential of using near-infrared spectroscopy (NIRS) to predict nutrient digestibility parameters (digestible protein and digestible energy) of compound diets when fed to barramundi. A series of 60 diets were assessed for their protein and energy digestibilities in a series of five experiments over a 5-year period from 2009 to 2014. Considerable variance was observed in the digestibility parameters of diets across the experiments, providing a suitable range in diet digestible protein and digestible energy values from which to develop a NIRS calibration. Samples of the same diets were also scanned using a diode array near-infrared spectrophotometer (DA-NIRS). The spectra were obtained by the DA-NIRS and were chemometrically calibrated against the digestible value data using multivariate analysis software. The results in terms of standard error of cross-validation (SECV), residual prediction deviation (RPD) and correlation coefficient (R2) show good relationships (R2 > 0.8) between the predicted and observed parameters for both the digestible protein and digestible energy parameters assessed. This study therefore demonstrates that it is possible to use NIRS technology to provide rapid estimates of the digestible protein and digestible energy values of compound diets for barramundi in near real time.&nbsp

A study of the discrete and interactive effects of different polysaccharides on the digestibility of diets fed to barramundi (Lates calcarifer)

This study examined the single, paired and combined inclusion effect of a range of different polysaccharide types on the dry matter, protein and energy digestibility of diets fed to barramundi (Lates calcarifer). The different polysaccharides included pregelled starch, cellulose, lignin and pectin. There were significant differences among the digestibility parameters of the diets with the different inclusion levels of each of the different polysaccharide types. Using a manova analysis, effects were noted for polysaccharide type, inclusion level and interaction terms on the digestibilities of dry matter, protein and energy. Cellulose addition resulted in a reduction in both dry matter and energy that was largely commensurate with its inclusion level, but its effect on protein digestibility was marginal. Starch had the least effect on any of the digestibility parameters of all the polysaccharide types examined. Pectin had the largest effect on dry matter, while lignin had the greatest impact on diet protein and energy digestion. In the diets with paired combinations of polysaccharides, lignin and pectin were responsible for negatively synergistic interactions in all digestibility parameters. These results show that different polysaccharide classes can have distinctly different effects on diet digestibility parameters. © 2015 John Wiley & Sons Ltd

Study of helicopterroll control effectiveness criteria

A study of helicopter roll control effectiveness based on closed-loop task performance measurement and modeling is presented. Roll control critieria are based on task margin, the excess of vehicle task performance capability over the pilot's task performance demand. Appropriate helicopter roll axis dynamic models are defined for use with analytic models for task performance. Both near-earth and up-and-away large-amplitude maneuvering phases are considered. The results of in-flight and moving-base simulation measurements are presented to support the roll control effectiveness criteria offered. This Volume contains the theoretical analysis, simulation results and criteria development

Comparison of faecal collection methods and diet acclimation times for the measurement of digestibility coefficients in barramundi (Lates calcarifer)

This study aimed to investigate the effects of two faecal collection methods (stripping and settlement) on the apparent digestibility coefficients (ADC) of dry matter, protein and energy of three different diets fed to barramundi. In a second experiment, the effect of acclimation time (i.e. number of days fed the diet) on the calculation of ADCs was also investigated. Each tank of fish was fed one of three diets for 12 days. Faeces were collected by both stripping and settlement, although only settlement was used prior to day seven of the acclimation period. Faeces were collected using the settlement method at regular intervals from day 1 to day 12. Comparisons between faecal collection methods were only made based on faecal material collected over a similar acclimation period. The collection of faeces by stripping produced more conservative ADCs, which were also more consistent than those obtained using the settlement technique. The calculated ADCs typically fluctuated for the first 3 days of collection before the variability diminished. Barramundi should be acclimated to diets for a minimum of 4 days before collection of faecal material, and collection by stripping is recommended to obtain the most reliable digestibility data

Effect of ration level and dietary docosahexaenoic acid content on the requirements for long-chain polyunsaturated fatty acids by juvenile barramundi (Lates calcarifer)

Juvenile barramundi were fed one of six diets containing differing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels. Fish were restricted fed on a pair-fed feeding regime to eliminate variability in feed intake, with two diets fed to satiety to examine the effects of fixed or variable feed rations on EFA requirements. Weight gain, feed intake, feed utilisation, and physical clinical signs were monitored. No effect of dietary DHA and EPA concentration, DHA:EPA ratio or total LC-PUFA level was observed on weight gain, growth rate, feed conversion ratio (FCR), survival or physical clinical health signs (P>0.05). Satiety fed fish had higher feed intake, final weight, weight gain and growth rate compared to their respective restrictively fed treatments (P<0.05). No effect of ration level on the responses to DHA concentration was observed. Body fatty acid composition was affected by diet, increasing dietary DHA resulted in higher body tissue DHA concentration, and a similar relationship was observed for EPA. Plasma haemoglobin increased with increasing DHA+EPA levels (P<0.05) while glutamate dehydrogenase increased for fish fed DHA+EPA in a 1:1 ratio, regardless of total dietary LC-PUFA (P<0.05). Juvenile barramundi may be fed diets containing as low as 1gkg-1 DHA without compromising growth or health status.&nbsp

Acute compartment syndrome of the lower limb following childbirth : a case report

Background: Acute compartment syndrome is a limb-threatening and occasionally life-threatening emergency that is rarely reported as a complication following childbirth. Prompt diagnosis is crucial to avoid permanent functional restriction or even the loss of the affected limb. Clinical signs and symptoms might be nonspecific, especially in the early stages; therefore, knowledge of predisposing risk factors and signs and symptoms of acute compartment syndrome is necessary to prevent long-term complications and amputation. Case presentation: This paper presents a case of a 26-year-old primiparous Sri Lankan woman who developed acute compartment syndrome of the lower right limb following childbirth by cesarean section. Conclusion: Acute compartment syndrome is an important differential diagnosis in the setting of sudden onset of lower limb pain following childbirth. Predisposing factors for its manifestation within an obstetric environment are augmented labor, the lithotomy position, postpartum hemorrhage, hypotension following epidural analgesia, and the use of vasoconstrictive agents. If left undiagnosed and untreated, acute compartment syndrome may cause permanent neurovascular deficit, leading to a poor functional result, tissue ischemia, limb amputation, and rhabdomyolysis. If severe, and in large compartments, it can lead to renal failure and death. Alertness and a high index of clinical suspicion for the possibility of acute compartment syndrome are required to avoid a delay in diagnosis, and intracompartmental pressure measurement can be used to confirm the diagnosis

An analysis of the effects of different dietary macronutrient energy sources on the growth and energy partitioning by juvenile barramundi, Lates calcarifer, reveal a preference for protein-derived energy

It is generally considered that fish respond to dietary energy densities on a consistent basis irrespective of what macronutrient source the dietary energy originates from. To test this assumption, two experiments were undertaken to establish the different roles of protein, lipid and starch as energy sources in underpinning nutritional bioenergetics in juvenile barramundi, Lates calcarifer. To do this, a range of ingredients were evaluated for their digestible protein (DP) and digestible energy (DE) value. Following this, a series of diets were formulated to an equivalent DE basis, and observed a minimum DP:DE ratio required for fish of 80 g. However, in each of the diets the proportion of DE available from protein, lipid or starch was varied to bias the contribution of each macronutrient on the origin that DE when fed to the fish. Growth of fish fed the protein diet was better than those fed the lipid diet, which was better than those fed the starch diet. Feed intake was lower in the protein diet than the lipid diet, and both were lower than the starch diet. Feed conversion was most efficient in the protein diet fed fish, which was better than the lipid diet fed fish, which was better than the starch diet fed fish. Whole fish composition varied among treatments, with differences observed in the dry matter composition, whole body lipid and gastrointestinal tract lipid content. Typically, lipid and dry matter composition were in synchrony and were usually higher in the starch fed fish and lower in the lipid fed fish. When flux of protein, lipid and energy was assessed in terms of deposition efficiencies, some significant differences were observed. Protein deposition efficiency was relatively conservative, but ranged from 33% in the starch diet fed fish to 41% in the lipid diet fed fish. Lipid deposition efficiency was more dramatic; ranging from 40% in the lipid diet to 182% in the starch diet. Energy deposition efficiency was relatively conservative among treatments, ranging from 50% to 56% efficient. Overall, the results from this study show that there is a clear hierarchy in preference for energy substrates by juvenile barramundi, such that protein > lipid > starch

An analysis of partial efficiencies of energy utilisation of different macronutrients by barramundi (Lates calcarifer) shows that starch restricts protein utilisation in carnivorous fish

This study examined the effect of including different dietary proportions of starch, protein and lipid, in diets balanced for digestible energy, on the utilisation efficiencies of dietary energy by barramundi (Lates calcarifer). Each diet was fed at one of three ration levels (satiety, 80 % of initial satiety and 60 % of initial satiety) for a 42-d period. Fish performance measures (weight gain, feed intake and feed conversion ratio) were all affected by dietary energy source. The efficiency of energy utilisation was significantly reduced in fish fed the starch diet relative to the other diets, but there were no significant effects between the other macronutrients. This reduction in efficiency of utilisation was derived from a multifactorial change in both protein and lipid utilisation. The rate of protein utilisation deteriorated as the amount of starch included in the diet increased. Lipid utilisation was most dramatically affected by inclusion levels of lipid in the diet, with diets low in lipid producing component lipid utilisation rates well above 1·3, which indicates substantial lipid synthesis from other energy sources. However, the energetic cost of lipid gain was as low as 0·65 kJ per kJ of lipid deposited, indicating that barramundi very efficiently store energy in the form of lipid, particularly from dietary starch energy. This study defines how the utilisation efficiency of dietary digestible energy by barramundi is influenced by the macronutrient source providing that energy, and that the inclusion of starch causes problems with protein utilisation in this species