Beyond BACI: Experimental designs for detecting human environmental impacts on temporal variations in natural populations

1991 ◽  
Vol 42 (5) ◽  
pp. 569 ◽  
Author(s):  
AJ Underwood

Biological effects of environmental impacts are usually defined simplistically in terms of changes in the mean of some biological variable. Many types of impact do not necessarily change long-run mean abundances. Here, designs for detection of environmental impact are reviewed and some of their shortcomings noted. New sampling designs to detect impacts that cause changes in temporal variance in abundance of populations, rather than their means, are described. These designs are effective at distinguishing pulse and press episodes of disturbance and could be used for other variables of interest (size, reproductive state, rate of growth, number of species, etc.) for monitoring. The designs require sampling different time-scales before and after a proposed development that might cause impact. Cases are discussed in which there is a single control location. Inadequacies of this approach for detection of environmental impact are mentioned, with some discussion of the consequences for management of impacts that cause temporal change rather than alterations of the mean abundance of a population.

1998 ◽  
Vol 65 (3) ◽  
pp. 479-489 ◽  
Author(s):  
ROGER A. KING ◽  
MARK M. MANO ◽  
RICHARD J. HEAD

There is considerable interest in the possibility that diet-derived isoflavonoids may help in protection against a number of chronic diseases common in Western society. Based on animal studies, however, concerns have been raised that consumption of isoflavonoids by infants and young children may be undesirable. Clover contains isoflavonoids and therefore may represent, via milk, a source of isoflavonoids in the human diet. In this study the concentrations of daidzein (7, 4′-dihydroxyisoflavone), genistein (5, 7, 4′-trihydroxyisoflavone) and equol (7-hydroxy-(4′-hydroxyphenyl)chroman) were measured using HPLC in cows' milk samples obtained from 76 farms in three Australian states. In addition, concentrations were measured in samples collected from one South Australian factory both before and after pasteurization. Concentrations in all samples were found to be extremely low. The mean daidzein concentration was <5 ng/ml. Mean genistein concentrations ranged from just detectable (∼2 ng/ml) in Victorian samples collected during summer to 20-30 ng/ml in samples from all states collected during spring when isoflavonoid-containing clover is most dominant in pasture. Mean equol concentrations ranged from 45±10 ng/ml in Victorian farm samples collected during summer to 293±52 ng/ml in Western Australian samples collected in spring. The mean concentrations of genistein and equol in post-pasteurization samples collected in spring were approximately double those for samples collected in autumn. Pasteurization had no effect on isoflavonoid concentrations. We conclude that the concentrations of isoflavonoids in Australian cows' milk are low and are therefore unlikely to have any pronounced biological effects in human consumers.


2019 ◽  
pp. 461-470
Author(s):  
Carl Johan Rydh

In order to achieve higher efficiency in use of materials and energy when providing a service or functionality of a product, indicator values can be used to point out the direction of development. The objective of the present study is to assess temporal variations of inventory data and identify significant environmental impacts for a product by using a life cycle assessment (LCA) approach. The study was restricted to a gate-to gate analysis of a Swedish manufacturer of NiCd batteries during the period 1983-1998. Inputs and outputs of materials and energy were compiled from environmental reports, which were related to the volume of produced batteries. The environmental impact was assessed by evaluation with different characterisation and weighting indices. The characterisation results regarding potential impact in resource use, global warming potential, acidification, eutrophication and aquatic ecotoxicity showed an average decrease of 2- 6 times during the period studied. The results of weighting showed that the environmental impact differed in the range -48 to 91 % per year according to the methods of ECO, ET, EDIP and EPS. The temporal variations of the results show the importance of choosing representative inventory data when making a LCA. Major reasons for the reduction in environmental impact were due to increased production meanwhile reducing dissipative emissions of metals. Evaluation with environmental indices is a great simplification of reality but it can help to identify significant environmental impacts of a product.


2017 ◽  
Vol 4 (2) ◽  
pp. 14
Author(s):  
Putri Megasari

Hepatitis has become a health problem in the world. The hepatitis virus infected many people. According to the teacher of MTsN 02 Bondowoso more than 20 students have hepatitis A viral infection. The purpose of this research was to know the differences of students' knowledge about hepatitis A before and after counseling in MTsN 02 Bondowoso 2015. This study used pre-experimental (pre-post test design). This study used stratified random sampling technique, 127 students from 270 sample involved this research,and 143 students was excluded. We used questionnaires to collect data. The results showed that the mean value of the students 'knowledge about hepatitis A before counseling in MTsN 02 Bondowoso 2015 was 83.96 with the lowest value of 37.5 and the highest value was 100. The mean value of the students' knowledge about hepatitis A after counseling in MTsN 02 Bondowoso 2015 was 93.21 with the lowest value waf 62.5 and the highest value was 100. Paired t test showed that t (-9.07) > t table (1.98), the null hypothesis (H0) was rejected. There was a difference between students' knowledge about hepatitis A before and after counseling in MTsN 02 Bondowoso 2015. This study showed that routine counseling by healthcare provider was important to prevent hepatitis A infection.; Keywords: counseling, knowledge of students, hepatitis


GIS Business ◽  
2019 ◽  
Vol 14 (6) ◽  
pp. 96-104
Author(s):  
P. Sakthivel ◽  
S. Rajaswaminathan ◽  
R. Renuka ◽  
N. R.Vembu

This paper empirically discovered the inter-linkages between stock and crude oil prices before and after the subprime financial crisis 2008 by using Johansan co-integration and Granger causality techniques to explore both long and short- run relationships.  The whole data set of Nifty index, Nifty energy index, BSE Sensex, BSE energy index and oil prices are divided into two periods; before crisis (from February 15, 2005 to December31, 2007) and after crisis (from January 1, 2008 to December 31, 2018) are collected and analyzed. The results discovered that there is one-way causal relationship from crude oil prices to Nifty index, Nifty energy index, BSE Sensex and BSE energy index but not other way around in both periods. However, a bidirectional causality relationship between BSE Energy index and crude oil prices during post subprime financial crisis 2008. The co-integration results suggested that the absence of long run relationship between crude oil prices and market indices of BSE Sensex, BSE energy index, Nifty index and Nifty energy index before and after subprime financial crisis 2008.


1984 ◽  
Vol 16 (3-4) ◽  
pp. 399-406
Author(s):  
Y Monbet

A study was conducted to gain insight on actual sedimentological and biological effects associated with the construction of an oil Terminal designed to receive 500 000 d.w.t. tankers. Field investigations and subsequent laboratory analyses were organized to evaluate the nature and magnitude of environmental changes on benthic macrofauna, three years after the end of the construction. Sediments were found to decrease dramatically in medium grain size in area sheltered by the newly built breakwater. Increase of percentage of silt and clays (90 % against 20 %) was observed leeward of the jetty. The benthic fauna showed significant modifications. Although the same community (Pectinaria kareni Abra alba) recolonized the bottom after the dredging of up to 30 × 106 m3 of sediments, increase in abundance occured. Biomass remained at a constant level and decrease of diversity was observed. Considering the rate of siltation, and assuming a constant siltation rate equal to the rate observed from 1975 to 1978, a simple regressive model relating biomass to mean grain size of sediments has been developped. This model allowed the prediction of biomass and production of the two principal species for the period 1978 – 1981. Continuous siltation within the harbor leads to a maximum of biomass from years after the end of the construction, followed by a decrease of standing stock. This process may be explained by the respective tolerance of the two principal species to increase silt contant and also probably by the accumulation of organic matter which may impede the development of natural populations.


2003 ◽  
Vol 128 (1) ◽  
pp. 17-26 ◽  
Author(s):  
David J. Kay ◽  
Richard M. Rosenfeld

OBJECTIVE: The goal was to validate the SN-5 survey as a measure of longitudinal change in health-related quality of life (HRQoL) for children with persistent sinonasal symptoms. DESIGN AND SETTING: We conducted a before and after study of 85 children aged 2 to 12 years in a metropolitan pediatric otolaryngology practice. Caregivers completed the SN-5 survey at entry and at least 4 weeks later. The survey included 5 symptom-cluster items covering the domains of sinus infection, nasal obstruction, allergy symptoms, emotional distress, and activity limitations. RESULTS: Good test-retest reliability ( R = 0.70) was obtained for the overall SN-5 score and the individual survey items ( R ≥ 0.58). The mean baseline SN-5 score was 3.8 (SD, 1.0) of a maximum of 7.0, with higher scores indicating poorer HRQoL. All SN-5 items had adequate correlation ( R ≥ 0.36) with external constructs. The mean change in SN-5 score after routine clinical care was 0.88 (SD, 1.19) with an effect size of 0.74 indicating good responsiveness to longitudinal change. The change scores correlated appropriately with changes in related external constructs ( R ≥ 0.42). CONCLUSIONS: The SN-5 is a valid, reliable, and responsive measure of HRQoL for children with persistent sinonasal symptoms, suitable for use in outcomes studies and routine clinical care.


Author(s):  
Aliki Peletidi ◽  
Reem Kayyali

Abstract Aims The primary aim of the programme was a minimum of a 5% weight reduction of the initial weight, while the secondary outcomes were a reduction in participants’ body mass index (BMI), waist circumference (WC), blood pressure (BP), AUDIT-C score and an increase in the Mediterranean diet (MD) score and an improvement in physical activity levels. Methods This 'before and after' study was a 10-week weight management (WM) programme and it was developed and delivered in community pharmacies in Patras chosen for convenience, thus consisting the first service of its type in Greece. The sample size was calculated (n = 96) based on the mean BMI for a Greek male and female individual, and the standard deviation (SD) of weight at baseline of 14 kg. Results Nearly every participant enrolled in the 20 participating pharmacies, 97.4% (n = 114/117), achieved the programme’s aim, losing at least 5% of their initial weight. The mean percentage of total weight loss of the 117 participants at the 10th week was 8.97% (SD 2.65), and the t-test showed statistically significant results (P-value < 0.001; 95% CI [8.48, 9.45]). A significant reduction in the waist-to-height ratio (WHtR) was observed in both male (P-value = 0.004) and female (P-value < 0.001) participants. The participants’ BP and AUDIT-C score and physical activity levels significantly improved (P-value < 0.001), as well as their MD score. Conclusion This study provides the first evidence that Greek pharmacists have the potential to play an important role within primary healthcare and that after training they are able to provide public health services for both the public’s benefit and their clinical role enhancement.


Author(s):  
Patrick Veit-Haibach ◽  
Martin W. Huellner ◽  
Martin Banyai ◽  
Sebastian Mafeld ◽  
Johannes Heverhagen ◽  
...  

Abstract Objectives The purpose of this study was the assessment of volumetric CT perfusion (CTP) of the lower leg musculature in patients with symptomatic peripheral arterial disease (PAD) before and after interventional revascularisation. Methods Twenty-nine consecutive patients with symptomatic PAD of the lower extremities requiring interventional revascularisation were assessed prospectively. All patients underwent a CTP scan of the lower leg, and hemodynamic and angiographic assessment, before and after intervention. Ankle-brachial pressure index (ABI) was determined. CTP parameters were calculated with a perfusion software, acting on a no outflow assumption. A sequential two-compartment model was used. Differences in CTP parameters were assessed with non-parametric tests. Results The cohort consisted of 24 subjects with an occlusion, and five with a high-grade stenosis. The mean blood flow before/after (BFpre and BFpost, respectively) was 7.42 ± 2.66 and 10.95 ± 6.64 ml/100 ml*min−1. The mean blood volume before/after (BVpre and BVpost, respectively) was 0.71 ± 0.35 and 1.25 ± 1.07 ml/100 ml. BFpost and BVpost were significantly higher than BFpre and BVpre in the treated limb (p = 0.003 and 0.02, respectively), but not in the untreated limb (p = 0.641 and 0.719, respectively). Conclusions CTP seems feasible for assessing hemodynamic differences in calf muscles before and after revascularisation in patients with symptomatic PAD. We could show that CTP parameters BF and BV are significantly increased after revascularisation of the symptomatic limb. In the future, this quantitative method might serve as a non-invasive method for surveillance and therapy control of patients with peripheral arterial disease. Key Points • CTP imaging of the lower limb in patients with symptomatic PAD seems feasible for assessing hemodynamic differences before and after revascularisation in PAD patients. • This quantitative method might serve as a non-invasive method, for surveillance and therapy control of patients with PAD.


2021 ◽  
Vol 108 (Supplement_2) ◽  
Author(s):  
C Luney ◽  
C Little

Abstract Introduction Audit of waste management in an elective orthopaedic complex was interrupted due Covid-19 pandemic. We investigated the impact of the enforced changes on theatre waste due to Covid-19. Method Over a 1week period data on waste bag availability and number of bags of each category of waste per surgical case in an elective theatre complex was collated; this was compared to waste generated during Covid-19 pandemic. Results Prior to Covid-19 only clinical waste bins were available in many non-dominant clinical areas providing evidence of inappropriate routine disposal of domestic/recyclable waste. Pre-Covid-19 a mean of 6waste bags were used per surgical case (3.7yellow clinical bags, 1.3black domestic bags, 0.4clear recycling bags), with Covid-19 changes to waste management practice the mean number of waste bags used per case increased to 11 (9 orange contaminated bags, 0.5black, 0.3clear bags). Conclusions Clinical waste management has a significant economic and environmental impact. Covid-19 has led to nearly all waste being deemed to be contaminated and so requiring incineration, with increased volumes of waste generated per case through widespread adoption of PPE. This has increased cost and reduced the ability to recycle non-contaminated waste.


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