Negligible heat strain in armored vehicle officers wearing personal body armor

Objectives This study evaluated the heat strain experienced by armored vehicle officers (AVOs) wearing personal body armor (PBA) in a sub-tropical climate. Methods Twelve male AVOs, aged 35-58 years, undertook an eight hour shift while wearing PBA. Heart rate and core temperature were monitored continuously. Urine specific gravity (USG) was measured before and after, and with any urination during the shift. Results Heart rate indicated an intermittent and low-intensity nature of the work. USG revealed six AVOs were dehydrated from pre through post shift, and two others became dehydrated. Core temperature averaged 37.4 ± 0.3°C, with maximum's of 37.7 ± 0.2°C. Conclusions Despite increased age, body mass, and poor hydration practices, and Wet-Bulb Globe Temperatures in excess of 30°C; the intermittent nature and low intensity of the work prevented excessive heat strain from developing.

Effects of acute multinutrient supplementation on rugby union game performance and recovery

Purpose: To investigate the effects of an acute multinutrient supplement on game-based running performance, peak power output, anaerobic by-products, hormonal profiles, markers of muscle damage, and perceived muscular soreness before, immediately after, and 24 h following competitive rugby union games. Methods: Twelve male rugby union players ingested either a comprehensive multinutrient supplement (SUPP), [RE-ACTIVATE:01], or a placebo (PL) for 5 d. Participants then performed a competitive rugby union game (with global positioning system tracking), with associated blood draws and vertical jump assessments pre, immediately post and 24 h following competition. Results: SUPP ingestion resulted in moderate to large effects for augmented 1st half very high intensity running (VHIR) mean speed (5.9 ± 0.4 vs 4.8 ± 2.3 m·min–1; d= 0.93). Further, moderate increases in 2nd half VHIR distance (137 ± 119 vs 83 ± 89 m; d= 0.73) and VHIR mean speed (5.9 ± 0.6 v 5.3 ± 1.7 m·min–1; d= 0.56) in SUPP condition were also apparent. Postgame aspartate aminotransferase (AST; 44.1 ± 11.8 vs 37.0 ± 3.2 UL; d= 1.16) and creatine kinase (CK; 882 ± 472 vs. 645 ± 123 UL; d= 0.97) measures demonstrated increased values in the SUPP condition, while AST and CK values correlated with 2nd half VHIR distance (r= –0.71 and r= –0.76 respectively). Elevated C-reactive protein (CRP) was observed postgame in both conditions; however, it was significantly blunted with SUPP (P= .05). Conclusions: These findings suggest SUPP may assist in the maintenance of VHIR during rugby union games, possibly via the buffering qualities of SUPP ingredients. However, correlations between increased work completed at very high intensities and muscular degradation in SUPP conditions, may mask any anticatabolic properties of the supplement.

The effect of post-match alcohol ingestion on recovery from competitive Rugby League matches

This study investigated the effects of alcohol ingestion on lower body strength and power, and physiological and cognitive recovery following competitive Rugby League matches. Nine male Rugby players participated in two matches, followed by one of two randomized interventions; a control or alcohol ingestion session. Four hours post-match, participants consumed either beverages containing a total of 1g of ethanol per kg bodyweight (vodka and orange juice; ALC) or a caloric and taste matched non-alcoholic beverage (orange juice; CONT). Pre, post, 2 h post and 16 h post match measures of countermovement jump (CMJ), maximal voluntary contraction(MVC), voluntary activation (VA), damage and stress markers of creatine kinase (CK), C-reactive protein (CRP), cortisol, and testosterone analysed from venous blood collection, and cognitive function (modified Stroop test) were determined. Alcohol resulted in large effects for decreased CMJ height(-2.35 ± 8.14 and -10.53 ± 8.36 % decrement for CONT and ALC respectively; P=0.15, d=1.40), without changes in MVC (P=0.52, d=0.70) or VA (P=0.15, d=0.69). Furthermore, alcohol resulted in a significant slowing of total time in a cognitive test (P=0.04, d=1.59), whilst exhibiting large effects for detriments in congruent reaction time (P=0.19, d=1.73). Despite large effects for increased cortisol following alcohol ingestion during recovery (P=0.28, d=1.44), post-match alcohol consumption did not unduly affect testosterone (P-0.96, d=0.10), CK (P=0.66, d=0.70) or CRP(P=0.75, d=0.60). It appears alcohol consumption during the evening following competitive rugby matches may have some detrimental effects on peak power and cognitive recovery the morning following a Rugby League match. Accordingly, practitioners should be aware of the potential associated detrimental effects of alcohol consumption on recovery and provide alcohol awareness to athletes at post-match functions.

Effects of acute multi-nutrient supplementation on rugby union match performance and recovery

Aim: To determine the effects of an acute multi-nutrient supplement on physiological, performance and recovery responses to intermittent-sprint running and muscular damage during rugby union matches. Methods: Using a randomised, double-blind, cross-over design, twelve male rugby union players ingested either 75 g of a comprehensive multi-nutrient supplement (SUPP), [Musashi] or 1 g of a taste and carbohydrate matched placebo (PL) for 5 days pre-competition. Competitive rugby union game running performance was then measured using 1 Hz GPS data (SPI10, SPI elite, GPSports), in addition to associated blood draws, vertical jump assessments and ratings of perceived muscular soreness (MS) pre, immediately post and 24 h post-competition. Baseline (BL) GPS data was collected during six competition rounds preceding data collection. Results: No significant differences were observed between supplement conditions for all game running, vertical jump, and ratings of perceived muscular soreness. However, effect size analysis indicated SUPP ingestion increased 1st half very high intensity running (VHIR) mean speed (d = 0.93) and 2nd half relative distance (m/min) (d = 0.97). Further, moderate increases in 2nd half VHIR distance (d = 0.73), VHIR m/min (d = 0.70) and VHIR mean speed (d = 0.56) in SUPP condition were also apparent. Moreover, SUPP demonstrated significant increases in 2nd half dist m/min, total game dist m/min and total game HIR m/min compared with BL data (P < 0.05). Further, large ES increases in VHIR time (d = 0.88) and moderate increases in 2nd half HIR m/min (d = 0.65) and 2nd half VHIR m/min (d = 0.74) were observed between SUPP and BL. Post-game aspartate aminotransferase (AST) (d = 1.16) and creatine kinase (CK) (d = 0.97) measures demonstrated increased ES values with SUPP, while AST and CK values correlated with 2nd half VHIR distance (r = −0.71 and r = −0.76 respectively). Elevated c-reactive protein (CRP) was observed post-game in both conditions, however was significantly blunted with SUPP (P = 0.05). Additionally, pre-game (d = 0.98) and post-game (d = 0.96) increases in cortisol (CORT) were apparent with SUPP. No differences were apparent between conditions for pH, lactate, glucose, HCO3, vertical jump assessments and MS (P > 0.05). Conclusion: These findings suggest SUPP may assist in the maintenance of VHIR speeds and distances covered during rugby union games, possibly via the buffering qualities of SUPP ingredients (i.e. caffeine, creatine, bicarbonate). While the mechanisms for these findings are unclear, the similar pH between conditions despite additional VHIR during SUPP may support this conclusion. Finally, correlations between increased work completed at very high intensities and muscular degradation in SUPP conditions, may mask any anti-catabolic properties of supplementation.

A hybrid simulation framework to assess the impact of renewable generators on a distribution network

With an increasing number of small-scale renewable generator installations, distribution network planners are faced with new technical challenges (intermittent load flows, network imbalances…). Then again, these decentralized generators (DGs) present opportunities regarding savings on network infrastructure if installed at strategic locations. How can we consider both of these aspects when building decision tools for planning future distribution networks? This paper presents a simulation framework which combines two modeling techniques: agent-based modeling (ABM) and particle swarm optimization (PSO). ABM is used to represent the different system units of the network accurately and dynamically, simulating over short time-periods. PSO is then used to find the most economical configuration of DGs over longer periods of time. The infrastructure of the framework is introduced, presenting the two modeling techniques and their integration. A case study of Townsville, Australia, is then used to illustrate the platform implementation and the outputs of a simulation.

Intrapleural analgesis following endoscopic scoliosis correction

Endoscopic scoliosis correction plays an important part in the surgical options available for treating adolescent idiopathic scoliosis. However, there is a paucity of literature examining optimum methods of analgesia following this type of surgery. The role of intrapleural analgesia is examined and described. In this study, local anaesthetic administration via an intrapleural catheter was found to be a safe and effective method of analgesia following endoscopic scoliosis correction. Post-operative pain following anterior scoliosis correction can be reduced to ‘mild’ levels by combined analgesia regimes. Surgeons may wish to expand its use into open or minimally invasive anterior scoliosis correction or anterior releases.

Flotation process response of Ok Tedi fluorine bearing minerals

Orebodies at Ok Tedi contain a number of different fluorine bearing minerals. Some of these minerals report to concentrate and are responsible for the presence of the penalty element, fluorine, within the concentrate. Previous analytical work has tended to examine geological samples for content, rather than determine the metallurgical behaviour of the different mineralogical species. This investigation utilised X-Ray Diffraction combined with Scanning Electron Microscope/Electron Microprobe to identify the fluorine bearing minerals in flotation test products. Seven fluorine bearing minerals were identified, viz., talc, phlogopite, amphibole (tremolite and actinolite), sphene, apatite, biotite and clay. Talc was found exclusively in the skarn ore type. Phlogopite and amphiboles (tremolite and actinolite) were found to occur in both skarn and porphyry ores, while sphene, apatite, biotite and clay were found only in the porphyry ores. Of the fluorine bearing minerals observed, only talc exhibited natural hydrophobicity to any significant degree. Phlogopite and the amphibole minerals were found to be hydrophillic, whilst the remaining minerals occurred in insufficient quantities to determine the flotation behaviour. Ok Tedi copper concentrate fluorine content prior to skarn ore treatment in the mill (typically 350ppm) was previously identified as deriving from phlogopite, while talc was believed to be the source of intermittent high concentrate fluorine contents when skarn ores were treated. This paper provides supporting evidence for this belief, and reports the nature of fluorine bearing mineral flotation behaviour.

Team communications in surgery - creating a culture of safety

As a key department within a healthcare organisation, the operating room is a hazardous environment, where the consequences of errors are high, despite the relatively low rates of occurrence. Team performance in surgery is increasingly being considered crucial for a culture of safety. The aim of this study was to describe team communication and the ways it fostered or threatened safety culture in surgery. Ethnography was used, and involved a 6-month fieldwork period of observation and 19 interviews with 24 informants from nursing, anaesthesia and surgery. Data were collected during 2009 in the operating rooms of a tertiary care facility in Queensland, Australia. Through analysis of the textual data, three themes that exemplified teamwork culture in surgery were generated: ‘‘building shared understandings through open communication’’; ‘‘managing contextual stressors in a hierarchical environment’’ and ‘‘intermittent membership influences team performance’’. In creating a safety culture in a healthcare organisation, a team’s optimal performance relies on the open discussion of teamwork and team expectation, and significantly depends on how the organisational culture promotes such discussions.

The effect of overnight sleep deprivation after competitive rugby league matches on postmatch physiological and perceptual recovery

PURPOSE: This study examined the effects of overnight sleep deprivation on recovery following competitive rugby league matches. METHODS: Eleven male, amateur rugby league players performed two competitive matches, followed by either a normal night's sleep (~8h; CONT) or a sleep deprived night (~0h; SDEP) in a randomised fashion. Testing was conducted the morning of the match, and immediately post-match, 2h post and the next morning (16h post-match). Measures included counter-movement jump (CMJ) distance, knee extensor maximal voluntary contraction (MVC), voluntary activation (VA), venous blood creatine kinase (CK) and C-reactive protein (CRP), perceived muscle soreness and a word-colour recognition cognitive function test. Percent change between post- and 16h post-match was reported to determine the effect of the intervention the next morning. RESULTS: Large effects indicated a greater post- to 16h post-match percentage decline in CMJ distance following SDEP compared to CONT (P=0.10-0.16; d=0.95-1.05). Similarly, the percentage decline in incongruent word-colour reaction times were increased in SDEP trials (P=0.007; d=1.75). Measures of MVC did not differ between conditions (P=0.40-0.75; d=0.13-0.33), though trends for larger percentage decline in VA were detected in SDEP (P=0.19; d=0.84). Further, large effects indicated higher CK and CRP responses 16h post-match during SDEP compared to CONT (P=0.11-0.87; d=0.80-0.88). CONCLUSIONS: Sleep deprivation negatively affected recovery following a rugby league match, specifically impairing CMJ distance and cognitive function. Practitioners should promote adequate post-match sleep patterns or adjust training demands the next day to accommodate the altered physical and cognitive state following sleep deprivation.

ECMO : the clinician’s view

Background: Extra corporeal membrane oxygenation (ECMO) is a complex rescue therapy used to provide cardiac and/or respiratory support for critically ill patients who have failed maximal conventional medical management. ECMO is based on a modified cardiopulmonary bypass (CPB) circuit, and can provide cardiopulmonary support for up-to several months. It can be used in a veno venous configuration for isolated respiratory failure, (VV-ECMO), or in a veno arterial configuration (VA-ECMO) where support is necessary for cardiac +/- respiratory failure. The ECMO circuit consists of five main components: large bore cannulae (access cannulae) for drainage of the venous system, and return cannulae to either the venous (in VV-ECMO) or arterial (in VA ECMO) system. An oxygenator, with a vast surface area of hollow filaments, allows addition of oxygen and removal of carbon dioxide; a centrifugal blood pump allows propulsion of blood through the circuit at upto 10 L/minute; a control module and a thermoregulatory unit, which allows for exact temperature control of the extra corporeal blood. Methods: The first successful use of ECMO for ARDS in adults occurred in 1972, and its use has become more commonplace over the last 30 years, supported by the improvement in design and biocompatibility of the equipment, which has reduced the morbidity associated with this modality. Whilst the use of ECMO in neonatal population has been supported by numerous studies, the evidence upon which ECMO was integrated into adult practice was substantially less robust. Results: Recent data, including the CESAR study (Conventional Ventilatory Support versus Extra corporeal membrane oxygenation for Severe Respiratory failure) has added a degree of evidence to the role of ECMO in such a patient population. The CESAR study analysed 180 patients, and confirmed that ECMO was associated with an improved rate of survival. More recently, ECMO has been utilized in numerous situations within the critical care area, including support in high-risk percutaneous interventions in cardiac catheter lab; the operating room, emergency department, as well in specialized inter-hospital retrieval services. The increased understanding of the risk:benefit profile of ECMO, along with a reduction in morbidity associated with its use will doubtless lead to a substantial rise in the utilisation of this modality. As with all extra-corporeal circuits, ECMO opposes the basic premises of the mammalian inflammation and coagulation cascade where blood comes into foreign circulation, both these cascades are activated. Anti-coagulation is readily dealt with through use of agents such as heparin, but the inflammatory excess, whilst less macroscopically obvious, continues un-abated. Platelet consumption and neutrophil activation occur rapidly, and the clinician is faced with balancing the need of anticoagulation for the circuit, against haemostasis in an acutely bleeding patient. Alterations in pharmacokinetics may result in inadequate levels of disease modifying therapeutics, such as antibiotics, hence paradoxically delaying recovery from conditions such as pneumonia. Key elements of nutrition and the innate immune system maysimilarly be affected. Summary: This presentation will discuss the basic features of ECMO to the nonspecialist, and review the clinical conundrum faced by the team treating these most complex cases.

Meal induced thermogenesis and appetite : methodological issues and responses to energy restriction

Diet Induced Thermogenesis (DIT) is the energy expended consequent to meal consumption, and reflects the energy required for the processing and digestion of food consumed throughout each day. Although DIT is the total energy expended across a day in digestive processes to a number of meals, most studies measure thermogenesis in response to a single meal (Meal Induced Thermogenesis: MIT) as a representation of an individual’s thermogenic response to acute food ingestion. As a component of energy expenditure, DIT may have a contributing role in weight gain and weight loss. While the evidence is inconsistent, research has tended to reveal a suppressed MIT response in obese compared to lean individuals, which identifies individuals with an efficient storage of food energy, hence a greater tendency for weight gain. Appetite is another factor regulating body weight through its influence on energy intake. Preliminary research has shown a potential link between MIT and postprandial appetite as both are responses to food ingestion and have a similar response dependent upon the macronutrient content of food. There is a growing interest in understanding how both MIT and appetite are modified with changes in diet, activity levels and body size. However, the findings from MIT research have been highly inconsistent, potentially due to the vastly divergent protocols used for its measurement. Therefore, the main theme of this thesis was firstly, to address some of the methodological issues associated with measuring MIT. Additionally this thesis aimed to measure postprandial appetite simultaneously to MIT to test for any relationships between these meal-induced variables and to assess changes that occur in MIT and postprandial appetite during periods of energy restriction (ER) and following weight loss. Two separate studies were conducted to achieve these aims. Based on the increasing prevalence of obesity, it is important to develop accurate methodologies for measuring the components potentially contributing to its development and to understand the variability within these variables. Therefore, the aim of Study One was to establish a protocol for measuring the thermogenic response to a single test meal (MIT), as a representation of DIT across a day. This was done by determining the reproducibility of MIT with a continuous measurement protocol and determining the effect of measurement duration. The benefit of a fixed resting metabolic rate (RMR), which is a single measure of RMR used to calculate each subsequent measure of MIT, compared to separate baseline RMRs, which are separate measures of RMR measured immediately prior to each MIT test meal to calculate each measure of MIT, was also assessed to determine the method with greater reproducibility. Subsidiary aims were to measure postprandial appetite simultaneously to MIT, to determine its reproducibility between days and to assess potential relationships between these two variables. Ten healthy individuals (5 males, 5 females, age = 30.2 ± 7.6 years, BMI = 22.3 ± 1.9 kg/m2, %Fat Mass = 27.6 ± 5.9%) undertook three testing sessions within a 1-4 week time period. During the first visit, participants had their body composition measured using DXA for descriptive purposes, then had an initial 30-minute measure of RMR to familiarise them with the testing and to be used as a fixed baseline for calculating MIT. During the second and third testing sessions, MIT was measured. Measures of RMR and MIT were undertaken using a metabolic cart with a ventilated hood to measure energy expenditure via indirect calorimetry with participants in a semi-reclined position. The procedure on each MIT test day was: 1) a baseline RMR measured for 30 minutes, 2) a 15-minute break in the measure to consume a standard 576 kcal breakfast (54.3% CHO, 14.3% PRO, 31.4% FAT), comprising muesli, milk toast, butter, jam and juice, and 3) six hours of measuring MIT with two, ten-minute breaks at 3 and 4.5 hours for participants to visit the bathroom. On the MIT test days, pre and post breakfast then at 45-minute intervals, participants rated their subjective appetite, alertness and comfort on visual analogue scales (VAS). Prior to each test, participants were required to be fasted for 12 hours, and have undertaken no high intensity physical activity for the previous 48 hours. Despite no significant group changes in the MIT response between days, individual variability was high with an average between-day CV of 33%, which was not significantly improved by the use of a fixed RMR to 31%. The 95% limits of agreements which ranged from 9.9% of energy intake (%EI) to -10.7%EI with the baseline RMRs and between 9.6%EI to -12.4%EI with the fixed RMR, indicated very large changes relative to the size of the average MIT response (MIT 1: 8.4%EI, 13.3%EI; MIT 2: 8.8%EI, 14.7%EI; baseline and fixed RMRs respectively). After just three hours, the between-day CV with the baseline RMR was 26%, which may indicate an enhanced MIT reproducibility with shorter measurement durations. On average, 76, 89, and 96% of the six-hour MIT response was completed within three, four and five hours, respectively. Strong correlations were found between MIT at each of these time points and the total six-hour MIT (range for correlations r = 0.990 to 0.998; P < 0.01). The reproducibility of the proportion of the six-hour MIT completed at 3, 4 and 5 hours was reproducible (between-day CVs ≤ 8.5%). This indicated the suitability to use shorter durations on repeated occasions and a similar percent of the total response to be completed. There was a lack of strong evidence of any relationship between the magnitude of the MIT response and subjective postprandial appetite. Given a six-hour protocol places a considerable burden on participants, these results suggests that a post-meal measurement period of only three hours is sufficient to produce valid information on the metabolic response to a meal. However while there was no mean change in MIT between test days, individual variability was large. Further research is required to better understand which factors best explain the between-day variability in this physiological measure. With such a high prevalence of obesity, dieting has become a necessity to reduce body weight. However, during periods of ER, metabolic and appetite adaptations can occur which may impede weight loss. Understanding how metabolic and appetite factors change during ER and weight loss is important for designing optimal weight loss protocols. The purpose of Study Two was to measure the changes in the MIT response and subjective postprandial appetite during either continuous (CONT) or intermittent (INT) ER and following post diet energy balance (post-diet EB). Thirty-six obese male participants were randomly assigned to either the CONT (Age = 38.6 ± 7.0 years, weight = 109.8 ± 9.2 kg, % fat mass = 38.2 ± 5.2%) or INT diet groups (Age = 39.1 ± 9.1 years, weight = 107.1 ± 12.5 kg, % fat mass = 39.6 ± 6.8%). The study was divided into three phases: a four-week baseline (BL) phase where participants were provided with a diet to maintain body weight, an ER phase lasting either 16 (CONT) or 30 (INT) weeks, where participants were provided with a diet which supplied 67% of their energy balance requirements to induce weight loss and an eight-week post-diet EB phase, providing a diet to maintain body weight post weight loss. The INT ER phase was delivered as eight, two-week blocks of ER interspersed with two-week blocks designed to achieve weight maintenance. Energy requirements for each phase were predicted based on measured RMR, and adjusted throughout the study to account for changes in RMR. All participants completed MIT and appetite tests during BL and the ER phase. Nine CONT and 15 INT participants completed the post-diet EB MIT and 14 INT and 15 CONT participants completed the post-diet EB appetite tests. The MIT test day protocol was as follows: 1) a baseline RMR measured for 30 minutes, 2) a 15-minute break in the measure to consume a standard breakfast meal (874 kcal, 53.3% CHO, 14.5% PRO, 32.2% FAT), and 3) three hours of measuring MIT. MIT was calculated as the energy expenditure above the pre-meal RMR. Appetite test days were undertaken on a separate day using the same 576 kcal breakfast used in Study One. VAS were used to assess appetite pre and post breakfast, at one hour post breakfast then a further three times at 45-minute intervals. Appetite ratings were calculated for hunger and fullness as both the intra-meal change in appetite and the AUC. The three-hour MIT response at BL, ER and post-diet EB respectively were 5.4 ± 1.4%EI, 5.1 ± 1.3%EI and 5.0 ± 0.8%EI for the CONT group and 4.4 ± 1.0%EI, 4.7 ± 1.0%EI and 4.8 ± 0.8%EI for the INT group. Compared to BL, neither group had significant changes in their MIT response during ER or post-diet EB. There were no significant time by group interactions (p = 0.17) indicating a similar response to ER and post-diet EB in both groups. Contrary to what was hypothesised, there was a significant increase in postprandial AUC fullness in response to ER in both groups (p < 0.05). However, there were no significant changes in any of the other postprandial hunger or fullness variables. Despite no changes in MIT in both the CONT or INT group in response to ER or post-diet EB and only a minor increase in postprandial AUC fullness, the individual changes in MIT and postprandial appetite in response to ER were large. However those with the greatest MIT changes did not have the greatest changes in postprandial appetite. This study shows that postprandial appetite and MIT are unlikely to be altered during ER and are unlikely to hinder weight loss. Additionally, there were no changes in MIT in response to weight loss, indicating that body weight did not influence the magnitude of the MIT response. There were large individual changes in both variables, however further research is required to determine whether these changes were real compensatory changes to ER or simply between-day variation. Overall, the results of this thesis add to the current literature by showing the large variability of continuous MIT measurements, which make it difficult to compare MIT between groups and in response to diet interventions. This thesis was able to provide evidence to suggest that shorter measures may provide equally valid information about the total MIT response and can therefore be utilised in future research in order to reduce the burden of long measurements durations. This thesis indicates that MIT and postprandial subjective appetite are most likely independent of each other. This thesis also shows that, on average, energy restriction was not associated with compensatory changes in MIT and postprandial appetite that would have impeded weight loss. However, the large inter-individual variability supports the need to examine individual responses in more detail.

Drying condition effects on fluidization quality and fluidization velocity at initial and final stages of cubical particulates for pet food

In this research fluidization behavior of cubical Bovine intestine samples was studied. Bovine intestine samples were heat pump dried at atmospheric pressure and at emperatures below and above the material freezing points. Experiments were conducted to study fluidization characteristics and drying kinetics at different drying conditions. Bovine particles were characterized according to Geldart classification and minimum fluidization velocity was calculated using Ergun Equation and generalized equation for all drying conditions at the beginning of the trials and end of the trials. Walli’s model was used to categorize stability of the fluidization at the beginning and end of the drying for each trial. Walli’s values determined were positive at the beginning and end of all trials indicating stable fluidisation at the beginning and end for each drying condition.

Influence of drying conditions on the moisture diffusion during single stage and two stage fluidized bed drying of bovine intestine for pet food

Bovine intestine samples were heat pump fluidized bed dried at atmospheric pressure and at temperatures below and above the material freezing points equipped with a continuous monitoring system. The investigation of the drying characteristics has been conducted in the temperature range -10~25oC and the airflow in the range 1.5~2.5 m/s. Some experiments were conducted as a single temperature drying experiments and others as two stage drying experiments employing two temperatures. An Arrhenius-type equation was used to interpret the influence of the drying air parameters on the effective diffusivity, calculated with the method of slopes in terms of energy activation, and this was found to be sensitivity of the temperature. The effective diffusion coefficient of moisture transfer was determined by Fickian method using uni-dimensional moisture movement in both moisture, removal by evaporation and combined sublimation and evaporation. Correlations expressing the effective moisture diffusivity and drying temperature are reported.

Utility of dexmedetomidine in sedation for radiofrequency ablation of atrial fibrillation.

[Letter to the Editor] I read with great interest the article recently published in the Journal of PeriAnesthesia Nursing that examined the utility of using dexmedetomidine (DEX) as an adjunct to midazolam and fentanyl for procedural sedation and analgesia during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF).1 With the view toward advancing knowledge about more effective medications for sedation in this challenging context, I offer the following insights for readers to consider regarding this study...

Percutaneous patent foramen ovale closure : outcomes with the Premere and Amplatzer devices

BACKGROUND: Transcatheter closure of patent foramen ovale (PFO) has rapidly evolved as the preferred management strategy for the prevention of recurrent cerebrovascular events in patients with cryptogenic stroke and presumed paradoxical embolus. There is limited outcome data in patients treated with this therapy particularly for the newer devices. METHODS: Data from medical records, catheter, and echocardiography databases on 70 PFO procedures performed was collected prospectively. RESULTS: The cohort consisted of 70 patients (mean age 43.6 years, range 19 to 77 years), of whom 51% were male. The indications for closure were cryptogenic cerebrovascular accident (CVA) or transient ischemic attack (TIA) in 64 (91%) and peripheral emboli in two (2.8%) patients and cryptogenic ST-elevation myocardial infarction in one (1.4%), refractory migraine in one (1.4%), decompression sickness in one (1.4%), and orthodeoxia in one (1.4%) patient, respectively. All patients had demonstrated right-to-left shunting on bubble study. The procedures were guided by intracardiac echocardiography in 53%, transesophageal echocardiography in 39%, and the remainder by transthoracic echo alone. Devices used were the Amplatzer PFO Occluder (AGA Medical) (sizes 18-35 mm) in 49 (70%) and the Premere device (St. Jude Medical) in 21 (30%). In-hospital complications consisted of one significant groin hematoma with skin infection. Echocardiographic follow-up at 6 months revealed that most patients had no or trivial residual shunt (98.6%), while one patient (1.4%) had a mild residual shunt. At a median of 11 months' follow-up (range 1 month to 4.3 years), no patients (0%) experienced further CVA/TIAs or paradoxical embolic events during follow-up. CONCLUSION: PFO causing presumed paradoxical embolism can be closed percutaneously with a low rate of significant residual shunting and very few complications. Recurrent index events are uncommon at medium-term (up to 4 years) follow-up.