Effect of oil pipeline construction on the benthic invertebrate community structure of Hodgson Creek, Northwest Territories

1991 ◽  
Vol 69 (8) ◽  
pp. 2154-2160 ◽  
Author(s):  
Robert J. Young ◽  
Gerald L. Mackie
Keyword(s):  
Community Structure ◽  
Northwest Territories ◽  
Negative Impact ◽  
Benthic Invertebrate ◽  
Invertebrate Drift ◽  
Pipeline Construction ◽  
Oil Pipeline ◽  
Right Of Way ◽  
Significant Difference ◽  
The Impact

During the ice-free seasons of 1984 and the winter and summer of 1985, we determined the effect of winter oil pipeline construction on benthic invertebrates of Hodgson Creek, Northwest Territories. Total suspended sediments increased from < 2 mgL−1 to > 300 mg L−1 at sampling stations downstream of the pipeline right-of-way during construction, with peak concentrations exceeding 3000 mg L−1. A concurrent increase in benthic invertebrate drift density from 2.6 to 37.6/100 m−3 was observed downstream of construction. The effects of pipeline installation were observed up to 5 weeks following the end of construction. Following the spring snowmelt in 1985, no significant difference in standing crop, species richness, or functional group composition between stations upstream and downstream of the pipeline right-of-way was observed. We concluded that the negative impact of pipeline construction was limited to the period between construction and spring ice breakup. The frequency and magnitude of spate events were sufficient to remove accumulated sediment. Thus, the impact of natural perturbations in Hodgson Creek was greater than the effect of pipeline construction on benthic community structure.

scholarly journals Mastectomy versus conservative surgical treatment: the impact on the quality of life of women with breast cancer

2010 ◽  
Vol 10 (1) ◽  
pp. 51-57 ◽  
Author(s):  
Daniela Francescato Veiga ◽  
Fabíola Soares Moreira Campos ◽  
Leda Marques Ribeiro ◽  
Ivanildo Archangelo Junior ◽  
Joel Veiga Filho ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Quality Of Life ◽  
Physical Functioning ◽  
Negative Impact ◽  
Young Patients ◽  
Conservative Surgery ◽  
Sf 36 ◽  
Significant Difference ◽  
The Impact

OBJECTIVES: to compare the impact of mastectomy and conservative surgery on the quality of life of patients with breast cancer. METHODS: an assessment was made of the quality of life of patients undergoing mastectomy or segmentary mastectomy, at the Pouso Alegre Clinical Hospital, in the Brazilian State of Minas Gerais, using SF-36. The patients were grouped by age (<50 years and >50 years) and years of schooling (<8 years and >8 years). The Mann-Whitney test was used to compare the groups with regard to the age and schooling domains of SF-36. RESULTS: a significant difference between the two groups was found in the domains of "physical functioning" (p=0.04) and "pain" (p=0.01): with the patients undergoing a mastectomy registering the worst scores. Young patients who had undergone a mastectomy displayed the worst quality of life in terms of "physical functioning" (p=0.03), "pain" (p=0.01) and "social functioning" (p=0.01); those undergoing conservative surgery aged over 50 years scored worst on "role emotional" (p=0.05). Patients undergoing a mastectomy with lower levels of schooling scored lower in "physical functioning" (p=0.01), "role physical" (p=0.05) and "pain" (p=0.05). Among those who had attended school for more than eight years, those having undergone a mastectomy scored less in the "pain" domain (p=0.04). CONCLUSIONS: patients who had undergone a mastectomy had worse results in the physical component of the evaluation of quality of life and this negative impact was more strongly felt among younger patients and those with lower levels of schooling.

Predation pressure, density-induced stress and tail regeneration: a casual-nexus situation or a bunch of independent factors?

2009 ◽  
Vol 30 (4) ◽  
pp. 471-482 ◽  
Author(s):  
Gerasimia Tsasi ◽  
Efstratios Valakos ◽  
Chrysi Simou ◽  
Panayiotis Pafilis
Keyword(s):  
Negative Impact ◽  
Predation Pressure ◽  
The Body ◽  
Defensive Strategy ◽  
Tail Regeneration ◽  
Regeneration Rate ◽  
Island Populations ◽  
Induced Stress ◽  
Significant Difference ◽  
The Impact

AbstractCaudal autotomy, the self-induced tail shedding from the body, is a common defensive strategy in lizards. Tail loss is followed rapidly by regeneration, revealing the importance of a fully functional tail. Predation pressure has been traditionally correlated with autotomy performance. However there is a lack of evidence regarding the impact of predation regime on tail regeneration. Another important factor that has been neglected is the population density. Though it is well established that crowding alters various life-history traits, the impact of density on caudal regeneration remains understudied. In this paper we compared three island populations of the Aegean Wall Lizard (Podarcis erhardii) that have evolved under different levels of predation pressure: whereas the Naxos population is exposed to numerous predators the Kopries and Daskalio islet populations experience low predation pressure. To evaluate the effect of density-induced stress on caudal regeneration, lizards were treated under two conditions of housing, in single and crowded (six individuals) terraria. Tail sheding occurred prior to this treatment following a standardised method. The length of regenerated tail was recorded weekly. Regeneration rate was higher in single terraria when compared to crowded, reflecting the negative impact of crowding. However we failed to detect any statistically significant difference between single and crowded terraria in the case of Naxos. We believe that the underlying reason must be the heavy predation pressure under which rapid tail regeneration, even under unfavourable conditions, is crucial for survival. It seems that the imperious need for regeneration counteracts density-induced stress.

Racial and low-income quotas in Brazilian universities: impact on academic performance

2018 ◽  
Vol 45 (1) ◽  
pp. 156-176
Author(s):  
Claudia Bueno Rocha Vidigal
Keyword(s):  
Academic Performance ◽  
Student Performance ◽  
Low Income ◽  
Family Income ◽  
Negative Impact ◽  
Public And Private ◽  
Content Type ◽  
The North ◽  
Significant Difference ◽  
The Impact

Purpose The purpose of this paper is to estimate the impact of racial and low-income quotas on academic performance of students from public and private universities in Brazil. Design/methodology/approach Using propensity score matching applied to student-level data from the National Examination of Student Performance conducted in 2012; this paper identifies the impact of the quota policy on academic performance considering all Brazilian universities. Findings The results indicate that there is no statistically significant difference in academic performance between students admitted under the racial quota and those who had the regular admission (non-quota students). The impact is positive, however, for students from the North region of Brazil and among those with very low family income, whereas a negative impact is observed for those from the Central-West region. In regard to the low-income quota, quota students perform worse than eligible non-quota students as their scores are, on average, 14 percent lower. Similar findings are observed when different subsamples are considered. Originality/value This paper’s main contribution is to provide a broader and more rigorous empirical approach than that presented by the existing literature in order to evaluate the impact of quota policies on academic achievement. Moreover, this study considers all Brazilian institutions whereas previous studies are limited to only one or a few universities.

Right-of-Way and Pipeline Monitoring in Permafrost: The Norman Wells Pipeline Experience

2002 ◽  
Author(s):  
Rick M. Doblanko ◽  
James M. Oswell ◽  
Alan J. Hanna
Keyword(s):  
Northwest Territories ◽  
Monitoring Program ◽  
Surveillance Program ◽  
Joint Research ◽  
Ambient Temperatures ◽  
Oil Pipeline ◽  
Right Of Way ◽  
Discontinuous Permafrost ◽  
The Government ◽  
Government Of Canada

Enbridge Pipelines (NW) Inc. (Enbridge) owns and operates a 323.9 mm outside diameter crude oil pipeline from Norman Wells, Northwest Territories, Canada to Zama, Alberta, Canada (Norman Wells Pipeline). The first of its kind in North America, this pipeline, completely buried in discontinuous permafrost, is approximately 869 kilometres in length. The pipeline, designed to operate at ambient temperatures, was constructed during the winter seasons of 1983–1984 and 1984–1985 and began operations in April 1985. Enbridge (formerly Interprovincial Pipe Line (NW) Ltd.), under various regulatory terms and conditions, is required to monitor and report the effects of pipeline construction and operations associated with the environment and right-of-way. The company has been an active participant in joint research and monitoring working groups consisting of various departments of the Government of Canada, Government of Northwest Territories, and other agencies. Over the past seventeen years, Enbridge has developed a monitoring and surveillance program that ensures the safe operation of the pipeline and protection of the environment. Any significant issues arising from the monitoring program result in mitigative actions based on engineering assessments. Furthermore, Enbridge is mandated to inform the appropriate agencies of issues resulting from the monitoring program. This paper will focus on the terrain and geotechnical monitoring programs initiated by Enbridge over its years of operation of this pipeline and will discuss topics including operations and maintenance activities key to pipelines installed in discontinuous permafrost, condition of the pipeline, and the on-going terrain and slope monitoring program.

scholarly journals Subtidal littering: Indirect effects on soft substratum macrofauna?

2008 ◽  
Vol 9 (2) ◽  
pp. 35 ◽  
Author(s):  
I. AKOUMIANAKI ◽  
P. KONTOLEFAS ◽  
S. KATSANEVAKIS ◽  
A. NICOLAIDOU ◽  
G. VERRIOPOULOS
Keyword(s):  
Community Structure ◽  
Sediment Surface ◽  
Long Run ◽  
Significant Difference ◽  
Before And After ◽  
Soft Substratum ◽  
One Year ◽  
The Impact ◽  
Control Surfaces ◽  
Macrofauna Community

Changes in macrofauna community structure, abundance and species richness were examined both before and one year after the deployment of plastic and glass bottles at littered (litter density: 16 items / 100 m2) and non-littered (control) surfaces at three unimpacted coastal areas of the western Saronikos Gulf (Greece). In parallel, LOI% at the adjacent sediments and changes in the composition of feeding types of the megaepifauna that colonized the litter were examined across treatments. Significant changes in macrofauna community structure were demonstrated between before and after littering. At only one of the sites was there detected a significant difference in macrofauna community structure between control and littered plots after littering. This difference was linked with a significant increase in the abundance of opportunistic polychaete species and LOI% levels in the sediment surface due to the entrapment of macrophytal debris within the littered surface. The study did not show a consistent direct response of macroinfauna community to litter and the associated megafauna. Unlike the megafauna attracted by litter items, soft-substratum macrofauna is less responsive to the addition of novel hard substrates in adjacent sediments. Alternatively, it could be that the impact of littering with small items triggers a macrofauna response detectable in the long-run.

scholarly journals Population birth outcomes in 2020 and experiences of expectant mothers during the COVID-19 pandemic: a ‘Born in Wales’ mixed methods study using routine data

2021 ◽  
Author(s):  
Hope Jones ◽  
Mike Seaborne ◽  
Laura Cowley ◽  
David Odd ◽  
Shantini Paranjothy ◽  
...  
Keyword(s):  
Birth Weight ◽  
Birth Outcomes ◽  
Online Survey ◽  
Negative Impact ◽  
National Level ◽  
Population Level ◽  
Significant Difference ◽  
Expectant Mothers ◽  
The Impact ◽  
Mothers Experiences

AbstractBackgroundPregnancy can be a stressful time and the COVID-19 pandemic has affected all aspects of life. This study aims to investigate the impact of the pandemic on population birth outcomes in Wales, rates of primary immunisations and examine expectant mothers’ experiences of pregnancy including self-reported levels of stress and anxiety.MethodsPopulation-level birth outcomes in Wales: Stillbirths, prematurity, birth weight and Caesarean section births before (2016–2019) and during (2020) the pandemic were compared using national-level routine anonymised data held in the Secure Anonymised Information Linkage (SAIL) Databank. The first three scheduled primary immunisations were compared between 2019 and 2020. Self-reported pregnancy experience: 215 expectant mothers (aged 16+) in Wales completed an online survey about their experiences of pregnancy during the pandemic. The qualitative survey data was analysed using codebook thematic analysis.FindingsThere was no significant difference between annual outcomes including gestation and birth weight, stillbirths, and Caesarean sections for infants born in 2020 compared to 2016-2019. There was an increase in late term births (≥42 weeks gestation) during the first lockdown (OR: 1.28, p=0.019) and a decrease in moderate to late preterm births (32-36 weeks gestation) during the second lockdown (OR: 0.74, p=0.001). Fewer babies were born in 2020 (N=29,031) compared to 2016-2019 (average N=32,582). All babies received their immunisations in 2020, but there were minor delays in the timings of vaccines. Those due at 8-weeks were 8% less likely to be on time (within 28-days) and at 16-weeks, they were 19% less likely to be on time. The pandemic had a negative impact on the mental health of 71% of survey respondents, who reported anxiety, stress and loneliness; this was associated with attending scans without their partner, giving birth alone, and minimal contact with midwives.InterpretationThe pandemic had a negative impact on mothers’ experiences of pregnancy; however, population-level data suggests that this did not translate to adverse birth outcomes for babies born during the pandemic.

scholarly journals Does Growing Economy And Better Governance Impede Banking Efficiency? A DEA Analysis

2015 ◽  
Vol 31 (6) ◽  
pp. 2213
Author(s):  
Ramiz Ur Rehman ◽  
Junrui Zhang ◽  
Rizwan Ali ◽  
Abdul Qadeer
Keyword(s):  
Corporate Governance ◽  
Interest Rates ◽  
Banking Sector ◽  
Negative Impact ◽  
Positive Impact ◽  
Foreign Banks ◽  
Significant Difference ◽  
Governance Practices ◽  
Growing Economy ◽  
The Impact

The paper estimates the efficiencies of Pakistani banking sector from 1998-2009. The analysis is further extended and regressed estimated banking efficiencies by using Data Envelopment Analysis (DEA), with macro-economic indicators and corporate governance variables of the banking sector. The purpose of this analysis is to determine the impact of overall economic conditions of a country and corporate governance practices on banking efficiencies. The results suggest that the corporate governance practices, like, board size, board independence have positive impact on overall banking sector efficiencies of Pakistan. Also, the GPD growth and interest rates have positive and negative impact on banking efficiencies respectively. The study has not found any significant difference in banking efficiencies of state-owned, private and foreign banks of Pakistan. 

The Effect of Cyberspace-based Education on the Well-Being of Caregivers of Elderly People with Dementia

2021 ◽  
Vol 14 ◽  
Author(s):  
Yadollah Abolfathi Momtaz ◽  
Parisa Mollaei ◽  
Parisa Taheri-Tanjani
Keyword(s):  
Elderly People ◽  
Negative Impact ◽  
Intervention Group ◽  
Well Being ◽  
World Health ◽  
Control Group ◽  
People With Dementia ◽  
Age Related ◽  
Significant Difference ◽  
The Impact

Introduction: One of the consequences of aging is the prevalence of chronic and age-related diseases, such as dementia. Caring for patients with dementia has a negative impact on the caregiver's well-being. This study aimed to examine the impact of cyberspace-based education on the well-being of caregivers of demented elderly people. Methods: This experimental study was done on a sample of 86 caregivers of elderly with dementia in 2018. The study sample was selected from memory clinic of Taleghani Hospital and randomly assigned into groups (intervention n = 43, control n = 43 groups). The well-being was measured using the World Health Organization - Five Well-Being Index (WHO-5), before and two months after the intervention. Cyberspace-based educational intervention was conducted for one month. The SPSS software version 23 was employed in data analysis. Results: The mean age of the caregivers in the intervention and control groups were (M = 51.95, SD = 10.90) and (M = 51.36, SD = 15.12) respectively. No significant difference was found between two groups in terms of age, gender and level of education. The results of analysis showed that while the well-being of the intervention group was significantly increased (t (38) = -11.38, P<0.001) the well-being in the control group was significantly reduced ( t(36) =4.71 , P<0.001). Conclusion: The findings showed that cyberspace-based education can improve the well-being of caregivers of the elderly with dementia.

scholarly journals Antimullerian Hormone Changes after Laparoscopic Ovarian Cystectomy for Endometrioma Compared with the Nonovarian Conditions

2014 ◽  
Vol 2014 ◽  
pp. 1-5
Author(s):  
Chamnan Tanprasertkul ◽  
Sakol Manusook ◽  
Charintip Somprasit ◽  
Sophapun Ekarattanawong ◽  
Opas Sreshthaputra ◽  
...  
Keyword(s):  
Ovarian Reserve ◽  
Negative Impact ◽  
Pelvic Surgery ◽  
Ovarian Cystectomy ◽  
Antimullerian Hormone ◽  
Significant Difference ◽  
The Mean ◽  
Antimüllerian Hormone ◽  
A Prospective Study ◽  
The Impact

Laparoscopic ovarian cystectomy is recommended for surgical procedure of endometrioma. The negative impact on ovarian reserve following removal had been documented. Little evidence had been reported for nonovarian originated effects.Objective.To evaluate the impact of laparoscopic ovarian cystectomy for endometrioma on ovarian reserve, measured by serum antimullerian hormone (AMH), compared to nonovarian pelvic surgery.Materials and Methods.A prospective study was conducted. Women who underwent laparoscopic ovarian cystectomy (LOC) and laparoscopic nonovarian pelvic surgery (NOS) were recruited and followed up through 6 months. Clinical baseline data and AMH were evaluated.Results.39 and 38 participants were enrolled in LOC and NOS groups, respectively. Baseline characteristics (age, weight, BMI, and height) and preoperative AMH level between 2 groups were not statistically different. After surgery, AMH of both groups decreased since the first week, at 1 month and at 3 months. However, as compared to the LOC group at 6 months after operation, the mean AMH of the NOS group had regained its value with a highly significant difference.Conclusion.This study demonstrated the negative impact of nonovarian or indirect effects of laparoscopic surgery to ovarian reserve. The possible mechanisms are necessary for more investigations.

scholarly journals Modelling the Diffusion of Investment Decisions on Modular Social Networks

Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Xiaokang Cheng ◽  
Narisa Zhao
Keyword(s):  
Social Networks ◽  
Community Structure ◽  
Social Network ◽  
Diffusion Model ◽  
Financial Market ◽  
Negative Impact ◽  
Investment Decisions ◽  
Negative Influence ◽  
Clustering Coefficient ◽  
The Impact

In the financial market, information and investment behaviors disseminate in investor social networks, and different contagion patterns may cause diverse investment trends. Prior studies have investigated the impact of investor social networks, but few have considered community structure. In this paper, we study the impact of the community structure of investor social networks on the diffusion of internet investment products. A two-stage diffusion model is proposed, and the clustering coefficient and modularity of an investor social network are considered. The results show that both modularity and the clustering coefficient have an impact on the diffusion velocity and scale and that the impact is most evident at the stage of explosive growth. The negative influence of a large modularity can be hardly mitigated by adjusting other factors. Furthermore, a decrease in modularity and an increase in the clustering coefficient can better facilitate diffusion when the temporary investment rate is high and can partly offset the negative impact of information discarding and divestment.

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