Assessing the influence and distribution of shrimp pond effluent in a tidal mangrove creek in north-east Australia

Effluent from a land based shrimp farm was detected in a receiving creek as changes in physical, chemical and biological parameters. The extent and severity of these changes depended on farm operations. This assessment was conducted at three different stages of shrimp-pond maturity, including (1) when the ponds were empty, (2) full and (3) being harvested. Methods for assessing farm effluent in receiving waters included physical/chemical analyses of the water column, phytoplankton bioassays and nitrogen isotope signatures of marine flora. Comparisons were made with an adjacent creek that served as the farms intake creek and did not directly receive effluent. Physical/chemical parameters identified distinct changes in the receiving creek with respect to farm operations. Elevated water column NH4+ (18.5+/-8.0 muM) and chlorophyll a concentrations (5.5+/-1.9 mug/l) were measured when the farm was in operation, in contrast to when the farm was inactive (1.3+/-0.3 muM and 1.2+/-0.6 mug/l, respectively). At all times, physically chemical parameters at the mouth of the effluent creek, were equivalent to control values, indicating effluent was contained within the effluent-receiving creek. However, elevated delta(15)N signatures of mangroves (up to similar to8parts per thousand) and macroalgae (up to similar to5parts per thousand) indicated a broader influence of shrimp farm effluent, extending to the lower regions of the farms intake creek. Bioassays at upstream sites close to the location of farm effluent discharge indicated that phytoplankton at these sites did not respond to further nutrient additions, however downstream sites showed large growth responses. This suggested that further nutrient loading from the shrimp farm, resulting in greater nutrient dispersal, will increase the extent of phytoplankton blooms downstream from the site of effluent discharge. When shrimp ponds were empty water quality in the effluent and intake creeks was comparable. This indicated that observed elevated nutrient and phytoplankton concentrations were directly attributable to farm operations. (C) 2003 Elsevier Ltd. All rights reserved.

Physical activity, exercise, and inflammatory markers in older adults: Findings from the health, aging and body composition study

OBJECTIVES: To examine the association between physical activity and inflammatory markers, with consideration for body fatness and antioxidant use. DESIGN: Cross-sectional study, using baseline data from the Health, Aging and Body Composition Study. SETTING: Metropolitan areas surrounding Pittsburgh, Pennsylvania, and Memphis, Tennessee. PARTICIPANTS: Black and white, well-functioning men and women (N=3,075), aged 70 to 79. MEASUREMENTS: Interviewer-administered questionnaires of previous-week household, walking, exercise, and occupational/volunteer physical activities. Analysis of covariance was used to examine the association between activity level and serum C-reactive protein (CRP), interleukin-6 (IL-6), and plasma tumor necrosis factor alpha (TNFalpha) with covariate adjustment. Antioxidant supplement use (multivitamin, vitamins E or C, beta carotene) was evaluated as an effect modifier of the association. RESULTS: Higher levels of exercise were associated with lower levels of CRP (P

Effect of carbohydrate supplementation on walking performance in peripheral arterial disease: A preliminary physiologic study

Objective: In this preliminary study we tested the effect of short-term carbohydrate supplementation on carbohydrate oxidation and walking performance in peripheral arterial disease. Methods: Eleven patients with peripheral arterial disease and intermittent claudication and 8 healthy control subjects completed several weeks of baseline exercise testing, then were given supplementation for 3 days with a carbohydrate solution and placebo. Maximal walking time was assessed with a graded treadmill test. Carbohydrate oxidation during a submaximal phase of this test was measured with indirect calorimetry. At the end of baseline testing a biopsy specimen was taken from the gastrocnemius muscle, and the active fraction of pyruvate dehydrogenase complex activity was determined. Results: Carbohydrate supplementation resulted in a significant increase in body weight and carbohydrate oxidation during exercise in patients with intermittent claudication and control subjects. Maximal walking time decreased by 3% in control subjects, whereas it increased by 6% in patients with intermittent claudication (group X treatment interaction, P < .05). There was a wide range of performance responses to carbohydrate supplementation among patients with claudication (-3%-37%). This effect was greater in poorer performers, and was negatively correlated (P < .05) with muscle pyruvate dehydrogenase complex activity. Conclusion: Preliminary data suggest that carbohydrate oxidation during exercise might contribute to exercise intolerance in more dysfunctional patients with intermittent claudication and that carbohydrate supplementation might be an effective therapeutic intervention in these patients.

Walking performance, oxygen uptake kinetics and resting muscle pyruvate dehydrogenase complex activity in peripheral arterial disease

In the present study, we tested the hypothesis that walking intolerance in intermittent claudication (IC) is related to both slowed whole body oxygen uptake (Vo(2)) kinetics and altered activity of the active fraction of the pyruvate dehydrogenase complex (PDCa) in skeletal muscle. Ten patients with IC and peripheral arterial disease [ankle/brachial index (ABI) = 0.73 +/- 0.13] and eight healthy controls (ABI = 1. 17 +/- 0.13) completed three maximal walking tests. From these tests, averaged estimates of walking time, peak Vo(2) and the time constant of Vo(2) (tau) during submaximal walking were obtained. A muscle sample was taken from the gastrocnemius medialis muscle at rest and analysed for PDCa and several other biochemical variables. Walking time and peak Vo(2) were approx. 50 % lower in patients with IC than controls, and tau was 2-fold higher (P < 0.05). r was significantly correlated with walking time (r = -0.72) and peak Vo(2) (r = -0.66) in patients with IC, but not in controls. PDCa was not significantly lower in patients with IC than controls; however, PDCa tended to be correlated with tau (r = -0.56, P = 0.09) in patients with IC, but not in controls (r = -0.14). A similar correlation was observed between resting ABI and tau (r = -0.63, P = 0.05) in patients with IC. These data suggest that the impaired Vo(2) kinetics contributes to walking intolerance in IC and that, within a group of patients with IC, differences in Vo(2) kinetics might be partly linked to differences in muscle carbohydrate oxidation.

Understanding environmental influences on walking - Review and research agenda

Background: Understanding how environmental attributes can influence particular physical activity behaviors is a public health research priority. Walking is the most common physical activity behavior of adults; environmental innovations may be able to influence rates of participation. Method: Review of studies on relationships of objectively assessed and perceived environmental attributes with walking. Associations with environmental attributes were examined separately for exercise and recreational walking, walking to get to and from places, and total walking. Results: Eighteen Studies were identified. Aesthetic attributes, convenience of facilities for walking (sidewalks, trails); accessibility of destinations (stores, park, beach); and perceptions about traffic and busy roads were found to be associated with walking for particular purposes. Attributes associated with walking for exercise were different front those associated with walking to get to and from places. Conclusions: While few studies have examined specific environment-walking relationships, early evidence is promising. Key elements of the research agenda are developing reliable and valid measures of environmental attributes and walking behaviors, determining whether environment-behavior relationships are causal, and developing theoretical models that account for environmental influences and their interactions with other determinants. (C) 2004 American Journal of Preventive Medicine.

Perceived environment attributes, residential location, and walking for particular purposes

Background: Identifying environmental factors that can influence physical activity is a public health priority. We examined associations of perceived environmental attributes with walking for four different purposes: general neighborhood walking, walking for exercise, walking for pleasure, and walking to get to and from places. Methods: Participants (n =399; 57% women) were surveyed by mail. They reported place of residence, walking behaviors, and perceptions of neighborhood environmental attributes. Results: Men with the most positive perceptions of neighborhood aesthetics were significantly more likely (odds ratio [OR] =7.4) to be in the highest category of neighborhood walking. Men who perceived the weather as not inhibiting their walking were much more likely (OR= 4.7) to be high exercise walkers. Women who perceived the weather as not inhibiting their walking were significantly more likely to be high neighborhood walkers (OR=3.8) and those with moderate perceptions of accessibility were much more likely to do more walking for pleasure (OR=3.5). Conclusions: Different environmental attributes were associated with different types of walking and these differed between men and women. Approaches to increasing physical activity might usefully focus on those attributes of the local environment that might influence particular subsets of walking behavior.

Comparison of beam theory and finite-element analysis with in vivo bone strain data from the alligator cranium

The mechanical behavior of the vertebrate skull is often modeled using free-body analysis of simple geometric structures and, more recently, finite-element (FE) analysis. In this study, we compare experimentally collected in vivo bone strain orientations and magnitudes from the cranium of the American alligator with those extrapolated from a beam model and extracted from an FE model. The strain magnitudes predicted from beam and FE skull models bear little similarity to relative and absolute strain magnitudes recorded during in vivo biting experiments. However, quantitative differences between principal strain orientations extracted from the FE skull model and recorded during the in vivo experiments were smaller, and both generally matched expectations from the beam model. The differences in strain magnitude between the data sets may be attributable to the level of resolution of the models, the material properties used in the FE model, and the loading conditions (i.e., external forces and constraints). This study indicates that FE models and modeling of skulls as simple engineering structures may give a preliminary idea of how these structures are loaded, but whenever possible, modeling results should be verified with either in vitro or preferably in vivo testing, especially if precise knowledge of strain magnitudes is desired. (c) 2005 Wiley-Liss, Inc.

Family violence: Walking the tight rope between maternal alienation and child safety

Mothers are often alienated from their children when child abuse is suspected or confirmed, whether she is the primary abuser of the child or not. An abusive or violent partner often initiates the process of maternal alienation from children as a control mechanism. When the co-occurrence of maternal and child abuse is not recognised, nurses and health professionals risk further alienating a mother from her children, which can have detrimental effects in both the short and long term. Evidence shows that when mothers are supported and have the necessary resources there is a reduction in the violence and abuse she and her children experience; this occurs even in situations where the mother is the primary abuser of her children. The family-centred care philosophy, which is widely accepted as the best approach to nursing care for children and their families, creates tension for nurses caring for children who are the victims of abuse as this care generally occurs away from the context of the family. This fragmented approach to caring for abused children can inadvertently undermine the mother-child relationship and further contribute to maternal alienation. This paper discusses the complexity of family violence for nurses negotiating the 'tight rope' between the prime concern for the safety of children and further contributing to maternal alienation, within a New Zealand context. The premise that restoration of the mother-child relationship is paramount for the long-term wellbeing of both the children and the mother provides the basis for discussing implications for nursing practice.

Controlled release of heparin from poly(epsilon-caprolactone) electrospun fibers

Sustained delivery of heparin to the localized adventitial surface of grafted blood vessels has been shown to prevent the vascular smooth muscle cell (VSMC) proliferation that can lead to graft occlusion and failure. In this study heparin was incorporated into electrospun poly(epsilon-caprolactone) (PCL) fiber mats for assessment as a controlled delivery device. Fibers with smooth surfaces and no bead defects could be spun from polymer solutions with 8% w/v PCL in 7:3 dichloromethane: methanol. A significant decrease in fiber diameter was observed with increasing heparin concentration. Assessment of drug loading, and imaging of fluorescently labeled heparin showed homogenous distribution of heparin throughout the fiber mats. A total of approximately half of the encapsulated heparin was released by diffusional control from the heparin/PCL fibers after 14 days. The fibers did not induce an inflammatory response in macrophage cells in vitro and the released heparin was effective in preventing the proliferation of VSMCs in culture. These results suggest that electrospun PCL fibers are a promising candidate for delivery of heparin to the site of vascular injury. (C) 2005 Elsevier Ltd. All rights reserved.

Efficient and stable nitritation and denitritation of ammonium-rich sludge dewatering liquor using an SBR with continuous loading

Separate treatment of dewatering liquor from anaerobic sludge digestion significantly reduces the nitrogen load of the main stream and improves overall nitrogen elimination. Such ammonium-rich wastewater is particularly suited to be treated by high rate processes which achieve a rapid elimination of nitrogen with a minimal COD requirement. Processes whereby ammonium is oxidised to nitrite only (nitritation) followed by denitritation with carbon addition can achieve this. Nitrogen removal by nitritation/denitritation was optimised using a novel SBR operation with continuous dewatering liquor addition. Efficient and robust nitrogen elimination was obtained at a total hydraulic retention time of 1 day via the nitrite pathway. Around 85-90% nitrogen removal was achieved at an ammonium loading rate of 1.2 g NH4+-N m(-3) d(-1). Ethanol was used as electron donor for denitritation at a ratio of 2.2gCODg(-1) N removed. Conventional nitritation/denitritation with rapid addition of the dewatering liquor at the beginning of the cycle often resulted in considerable nitric oxide (NO) accumulation during the anoxic phase possibly leading to unstable denitritation. Some NO production was still observed in the novel continuous mode, but denitritation was never seriously affected. Thus, process stability can be increased and the high specific reaction rates as well as the continuous feeding result in decreased reactor size for full-scale operation. (c) 2006 Elsevier Ltd. All rights reserved.

Individual calibration for estimating free-living walking speed using the MTI monitor

Purpose: This study was conducted to devise a new individual calibration method to enhance MTI accelerometer estimation of free-living level walking speed. Method: Five female and five male middle-aged adults walked 400 m at 3.5, 4.5, and 5.5 km(.)h(-1), and 800 in at 6.5 km(.)h(-1) on an outdoor track, following a continuous protocol. Lap speed was controlled by a global positioning system (GPS) monitor. MTI counts-to-speed calibration equations were derived for each trial, for each subject for four such trials with each of four MTI, for each subject for the average MTI. and for the pooled data. Standard errors of the estimate (SEE) with and without individual calibration were compared. To assess accuracy of prediction of free-living walking speed, subjects also completed a self-paced, brisk 3-km walk wearing one of the four MTI, and differences between actual and predicted walking speed with and without individual calibration were examined. Results: Correlations between MTI counts and walking speed were 0.90 without individual calibration, 0.98 with individual calibration for the average MTI. and 0.99 with individual calibration for a specific MTI. The SEE (mean +/- SD) was 0.58 +/- 0.30 km(.)h(-1) without individual calibration, 0.19 +/- 0.09 km h(-1) with individual calibration for the average MTI monitor, and 0.16 +/- 0.08 km(.)h(-1) with individual calibration for a specific MTI monitor. The difference between actual and predicted walking speed on the brisk 3-km walk was 0.06 +/- 0.25 km(.)h(-1) using individual calibration and 0.28 +/- 0.63 km(.)h(-1) without individual calibration (for specific accelerometers). Conclusion: MTI accuracy in predicting walking speed without individual calibration might be sufficient for population-based studies but not for intervention trials. This individual calibration method will substantially increase precision of walking speed predicted from MTI counts.

Leflunomide improves psoriasis in patients with psoriatic arthritis: An in-depth analysis of data from the TOPAS study

Background: Leflunomide has shown promise in the treatment of psoriasis. Objective: To provide an in-depth analysis of the effect of leflunomide on psoriasis in patients with psoriatic arthritis (PsA). Methods: 190 patients with plaque psoriasis (at least 3% skin involvement) and active PsA were randomized to double-blind treatment with leflunomide (100 mg/day loading dose for 3 days followed by 20 mg/day orally) or placebo for 24 weeks. Results: As previously reported, leflunomide resulted in a significantly higher Psoriatic Arthritis Response Criteria response rate than placebo (58.9 vs. 29.7%; p < 0.0001). Significant differences in favor of leflunomide were also observed in the Psoriasis Area and Severity Index (PASI 50 in 30.4% of patients vs. 18.9% for placebo; p = 0.05), target lesion response (46.4 vs. 25.3%; p = 0.0048), combined skin and joint response (27.2 vs. 8.9%; p < 0.0001), Dermatology Life Quality Index (improvement of 1.9 points vs. 0.2; p = 0.0173) and certain SF-36 subdomains. Dermatological responses were observed at the earliest examination (4 weeks) and increased throughout the 24-week study. Conclusion: Once-daily oral leflunomide is an effective and convenient treatment for PsA and plaque psoriasis. Copyright (c) 2006 S. Karger AG, Basel.

Neighborhood environmental factors correlated with walking near home: Using SPACES

Purpose: The physical environment plays an important role in influencing participation in physical activity, although the specific factors that are correlated with different patterns of walking remain to be determined We examined correlations between physical environmental factors and self-reported walking for recreation and transport near home. Methods: The local neighborhood environments (defined as a 400-m radius from the respondent's home) of 1678 adults were assessed for their suitability for walking. The environmental data were collected during 2000 using the Systematic Pedestrian and Cycling Environmental Scan (SPACES) instrument together with information from other sources. We used logistic regression modeling to examine the relationship between the attributes of the physical environment and the self-reported walking behavior undertaken near home. Results: Functional features were correlated with both walking for recreation (odds ratio (OR) 1.62; 95% confidence interval (Cl): 1.20-2.19) and for transport (OR 1.30; 95% Cl: 0.97-1.73). A well-maintained walking surface was the main functional factor associated with walking for recreation (OR 2.04; 95% Cl: 1.43-2.91) and for transport (OR 2.13; 95% Cl: 1.53-2.96). Destination factors, such as shops and public transport, were significantly correlated with walking for transport (OR 1.80; 95% Cl: 1.33-2.44), but not recreation. Conclusion: The findings suggest that neighborhoods with pedestrian facilities that are attractive and comfortable and where there are local destinations (such as shops and public transport) are associated with walking near home.

RNA Loading of Leukemic Antigens into Cord Blood–Derived Dendritic Cells for Immunotherapy

The manipulation of dendritic cells (DCs) ex vivo to present tumor-associated antigens for the activation and expansion of tumor-specific cytotoxic T lymphocytes (CTLs) attempts to exploit these cells’ pivotal role in immunity. However, significant improvements are needed if this approach is to have wider clinical application. We optimized a gene delivery protocol via electroporation for cord blood (CB) CD34+ DCs using in vitro–transcribed (IVT) mRNA. We achieved > 90% transfection of DCs with IVT-enhanced green fluorescent protein mRNA with > 90% viability. Electroporation of IVT-mRNA up-regulated DC costimulatory molecules. DC processing and presentation of mRNA-encoded proteins, as major histocompatibility complex/peptide complexes, was established by CTL assays using transfected DCs as targets. Along with this, we also generated specific antileukemic CTLs using DCs electroporated with total RNA from the Nalm-6 leukemic cell line and an acute lymphocytic leukemia xenograft. This significant improvement in DC transfection represents an important step forward in the development of immunotherapy protocols for the treatment of malignancy.

Socio-demographic variations in walking for transport and for recreation or exercise among adult Australians

Background: Walking is integral to strategies to promote physical activity. We identified socio-demographic variations in walking for transport, and for recreation or exercise. Methods: Representative population data (n = 3392) from Australia were collected using computer assisted telephone interviewing, to examine adults’ participation in moderate- or brisk-paced walking for transport and walking for recreation or exercise; walking “sufficient” to meet the current public health guideline (> 150 min/wk); and, the contributions of total walking to meeting the guideline for total physical activity. Results: Rates of sufficient walking for transport (10% for men, 9% for women) were lower than those for walking for recreation or exercise (14% for both genders). Few socio-demographic differences emerged. Men over age 60 y were significantly less likely (OR = 0.40) to walk for transport; men age 45 to 59 y were more likely (OR = 1.56) to walk for recreation or exercise. Walking contributed more toward meeting the current public health guideline among women (15% to 21%) than among men (6% to 8%). Conclusions: There is potential for socially equitable increases in participation, through a focus on both walking for transport and on walking for recreation or exercise; attention to gender differences would be helpful.