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Structural analysis of energy market failure: Empirical evidence from US
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel UniversityThis thesis is concerned with the econometric modelling of gasoline prices in US. The intention is to characterize the market process in this crucial and significant industry. Overall we have been seeking to identify a mechanism to signal and measure market failure and consequently improve market performance. Firstly we examine the time series properties of gasoline prices using the criteria for perfect arbitrage to test market efficiency from the stationarity of price proportions. This is done by considering market efficiency across in different regions of the US, by applying a range of different stationary tests. In this analysis we collected a comprehensive data set of gasoline prices for all regions of the US mainland for the longest period available. Forni (2004), outlined reasons why the analysis of price proportions may be advantageous; especially when the sample is limited. Stationarity corresponds to a broad market, it is found here that the US gasoline market is on average broad. Except for the Gulf Coast and Lower Atlantic, which may be seen as economically and/or geographically separated, market structure in the rest of the US would not appear to be a problem Next we investigate possible long-run price leadership in the US gasoline market and the inter-relatedness of price behaviour relevant to a competitive market. Following Hunter & Burke (2007) and Kurita (2008) market definition is tested. This is done on an extended regional data set to Kurita and following the analysis in Hunter and Burke on a set of company data for the US.We analysed long-run price leadership through the cointegrated vector auto-regression (VAR) to identify key characteristics of long-run structure in the gasoline market. The analysis of the system of regional prices confirms problems with the Gulf Coast and Lower Atlantic, but also based on the finding that the cointegrating rank is less than N-1 using both types of data ( regional price data and company price data) and the findings on weak exogenity it is suggested that competition across the whole of the US is further limited. We applied further tests to company data on prices and quantity data to investigate further the need to regulate for potential anomalies and to capture more directly consumer harm. The variance screening method applied to recent weekly data indicates that there is too little variation in gasoline prices and this would seem to support the cointegration study. Furthermore we applied a dynamic disequilibrium analysis to attempt to identify long-run demand and supply in the gasoline market. Finding significant variables using the Phillips-Hansen fully modified estimation of the switching regression is necessary to distinguish two long-run equations (S&D). Moreover a comparison is made with a Markov Switching Model (MSM) of prices and this suggests a similar pattern of regime to the quantity information analysed in by our disequilibrium model
Through a mechanism-based approach, nanoparticles of cerium and yttrium may improve the outcome of pancreatic islet isolation
AbstractInsulin dependent diabetes mellitus (IDDM) is a global disease with high economic and social burden. A potential cure for type 1 diabetes is pancreatic islet transplantation. Despite recent improvements, islets are faced with various types of stress related to the isolation and transplantation procedure. Oxidative stress plays an essential role in cell damage during islet isolation and transplantation procedures. In this article, we hypothesise that a combination of cerium and yttrium oxide nanoparticles, as a power antioxidant with free-radical-scavenging activity, because of enhancing the survival or viability of cells in vitro can improve islet transplantation. No doubt, administration of this improvement can be used in diabetes treatment
Correlation of serum and salivary CA15-3 levels in patients with breast cancer
Objectives: The aim of this study was to assess the relationship between serum and saliva levels of cancer antigen (CA) 15-3 and to compare them between women with and without breast cancer. Study design: A case-control study was carried out on 61 women aged 28-69 years, including women with and without breast cancer (26 as part of the case study and 35 as part of the control group) conducted at the Emam Khomeini Hospital, Tehran University of Medical Sciences. CA15-3 levels were assayed in serum and unstimulated whole saliva by EIA. Unpaired t-test, one-way ANOVA and Pearson correlation were used as statistical analysis. Results: The salivary and serological levels of CA15-3 in the cancer patients were significantly higher (P <0.01) than the salivary and serum levels of healthy controls. They were also higher in stage 2 than in stage 1 in cancer patients. However, the saliva flow rate was significantly lower in the cancer patients (P <0.01). There was a significant positive correlation between serum and saliva CA15-3 concentration (r = 0.614) and also between serum concentration and saliva output of CA15-3 (r = 0.541). Conclusion: The results of the study suggest that salivary CA15-3 may have potential use in the initial detection of breast cancer in women
Evaluating the Effectiveness of Using a Progressive Muscle Relaxation Technique on the Self-Efficacy of Breastfeeding in Mothers With Preterm Infants.
BACKGROUND
Breast milk is a God-given gift that conveys a mother's love and compassion and that is made according to the needs and age of the child. Mothers who are interested in the welfare of their newborns tend to breastfeed their children. Training programs have been shown to improve breastfeeding self-efficacy in terms of both duration and amount.
PURPOSE
The aim of this study was to evaluate the effect of using the progressive muscle relaxation (PMR) technique on the self-efficacy of breastfeeding in mothers with preterm infants.
METHODS
A clinical trial approach was used. Sixty mothers with preterm infants were randomly assigned to either the intervention or control group. The clinical trial ran for a period of 2 months for both groups. At 24-72 hours postpartum, the researcher used the Jacobson method to provide 30-45 minutes of individual training to the intervention group participants on PMR. Under the Jacobson method, mothers contract the 16 groups of muscles until they experience the feeling of pressure and then relax these muscles. The tools used in this study were the standard questionnaire of Dennis breastfeeding self-efficacy, which was completed by the participants at baseline, at the end of the fourth week, and during the eighth week. Data were analyzed using SPSS software.
RESULTS
No significant difference was observed between the intervention and control groups in terms of demographic variables (p > .05). Independent t tests found no significant difference between the two groups (p = .45) in terms of mean score of maternal breastfeeding self-efficacy at pretest and significantly higher scores for the intervention group than the control group at both 4 (p = .001) and 8 (p < .001) weeks posttest. Furthermore, the analysis of variance test showed significant differences in the mean score of breastfeeding self-efficacy for the intervention group between pretest and the first posttest and between the first posttest and the second posttest, respectively (p < .001).
CONCLUSIONS/IMPLICATIONS FOR PRACTICE
Considering the effect of relaxation training on the breastfeeding self-efficacy of mothers with preterm infants, training and performing these exercises as an effective and low-cost method to improve the health of mothers, particularly mothers of preterm infants, are recommended. The PMR technique facilitates the self-efficacy of breastfeeding in mothers with preterm infants and should be considered as an effective strategy to improve nursing care and the provision of better support services for mothers who breastfeed their infants
LncRNA–miRNA–mRNA Networks of Gastrointestinal Cancers Representing Common and Specific LncRNAs and mRNAs
Gastrointestinal (GI) cancers are responsible for approximately half of cancer-related
deaths, highlighting the need for the identification of distinct and common features in
their clinicopathological characteristics. Long ncRNA (lncRNAs), which are involved in
competitive endogenous RNA (ceRNA) networks with critical roles in biological processes,
constitute a substantial number of non-coding RNAs. Therefore, our study aimed to
investigate the similarities and differences in the ceRNA networks of The Cancer Genome
Atlas (TCGA)-GI cancers. We performed a comprehensive bioinformatics analysis of
ceRNA networks for TCGA-GI cancers in terms of the deferential mRNA, lncRNA, and
miRNA expression levels, ceRNA networks, overall survival analysis, correlation analysis,
pathological cancer stages, and gene set enrichment analysis. Our study revealed several
common and distinct mRNAs and lncRNAs with prognostic values in these networks. It
was specifically noteworthy that MAGI2-AS3 lncRNA was found to be shared in almost all
GI cancers. Moreover, the most common shared mRNAs between GI cancers were
MEIS1, PPP1R3C, ADAMTSL3, RIPOR2, and MYLK. For each cancer ceRNA network, we
found that the expression level of a number of lncRNAs and mRNAs was specific.
Furthermore, our study provided compelling evidence that several genes, most notably
KDELC1, can act as novel proto-oncogenes in cancers. This, in turn, can highlight their role
as new prognostic and therapeutic targets. Moreover, we found cell cycle and extracellular
matrix structural constituent as the top shared KEGG and molecular function, respectively,
among GI cancers. Our study revealed several known lncRNAs and known and unknown
mRNAs in GI cancers with diagnostic and prognostic value
Diabetic Neuropathy and Oxidative Stress: Therapeutic Perspectives
Diabetic neuropathy (DN) is a widespread disabling disorder comprising peripheral nerves' damage. DN develops on a background of hyperglycemia and an entangled metabolic imbalance, mainly oxidative stress. The majority of related pathways like polyol, advanced glycation end products, poly-ADP-ribose polymerase, hexosamine, and protein kinase c all originated from initial oxidative stress. To date, no absolute cure for DN has been defined; although some drugs are conventionally used, much more can be found if all pathophysiological links with oxidative stress would be taken into account. In this paper, although current therapies for DN have been reviewed, we have mainly focused on the links between DN and oxidative stress and therapies on the horizon, such as inhibitors of protein kinase C, aldose reductase, and advanced glycation. With reference to oxidative stress and the related pathways, the following new drugs are under study such as taurine, acetyl-L-carnitine, alpha lipoic acid, protein kinase C inhibitor (ruboxistaurin), aldose reductase inhibitors (fidarestat, epalrestat, ranirestat), advanced glycation end product inhibitors (benfotiamine, aspirin, aminoguanidine), the hexosamine pathway inhibitor (benfotiamine), inhibitor of poly ADP-ribose polymerase (nicotinamide), and angiotensin-converting enzyme inhibitor (trandolapril). The development of modern drugs to treat DN is a real challenge and needs intensive long-term comparative trials
The Effect of Mode of Delivery on Postpartum Sexual Functioning in Primiparous Women
Objective: To evaluate the effect of mode of delivery on postpartum sexual functioning in primiparous women.
Methods: In this cross-sectional descriptive study, 150 primiparous women in postpartum period, who attended the family planning or vaccination clinics, were enrolled for the study. Eighty-one had vaginal delivery with episiotomy and 69 had experienced cesarean section. Sexual function was evaluated by the Female Sexual Function Index within 3 and 6 months postpartum.
Results: About 29% in vaginal delivery group and 37% in cesarean delivery group had resumed their sexual intercourses four weeks after delivery (p=0.280).There were no significant differences between mode of delivery and sexual functioning, including desire, arousal, lubrication, orgasm, satisfaction and pain.
Conclusion: The present study showed that postpartum sexual functioning was not associated with the type of delivery