345 research outputs found
The Effect of Relational Constructs on Relationship Performance
We examine the effect of relational constructs, such as satisfaction, trust and commitment on relationship performance (that is, positive word-of-mouth communication and the margin provided by each customer) of customers of an insurance company. A central issue concerns the effect of duration on the associations between relational constructs and relationship performance. Our empirical results provide strong evidence of duration dependent effects of satisfaction and trust, but we find only weak evidence of such effects on performance.Insurance industry;Performance;Relationship duration;Relationship marketing
Association between consumption of black tea and iron status in adult Africans in the North West Province: The THUSA study
The association between black tea consumption and iron status was investigated in a sample of African adults participating in the cross-sectional THUSA (Transition and Health during Urbanization of South Africans) study in the North West Province, South Africa. Data were analysed from 1605 apparently healthy adults aged 15-65 years by demographic and FFQ, anthropometric measurements and biochemical analyses. The main outcome measures were Hb and serum ferritin concentrations. No associations were seen between black tea consumption and concentrations of serum ferritin (men P=0.059; women P=0.49) or Hb (men P=0.33; women P=0.49). Logistic regression showed that tea consumption did not significantly increase risk for iron deficiency (men: OR 1.36; 95 % CI 0.99, 1.87; women: OR 0.98; 95 % CI 0.84, 1.13) nor for iron deficiency anaemia (men: OR 1.28: 95 % Cl 0.84, 1.96; women: OR 0.93; 95 % Cl 0.78, 1.11). Prevalence of iron deficiency and iron deficiency anaemia was especially high in women: 21.6 and 14.6 %, respectively. However, the likelihood of iron deficiency and iron deficiency anaemia was not significantly explained by tea consumption in sub-populations which were assumed to be at risk for iron deficiency. Regression of serum ferritin levels on tea consumption in women : 40 years, adults with a daily iron intak
The Effect of Relational Constructs on Relationship Performance
We examine the effect of relational constructs, such as satisfaction, trust and commitment on relationship performance (that is, positive word-of-mouth communication and the margin provided by each customer) of customers of an insurance company. A central issue concerns the effect of duration on the associations between relational constructs and relationship performance. Our empirical results provide strong evidence of duration dependent effects of satisfaction and trust, but we find only weak evidence of such effects on performance
The effect of relational constructs on customer referrals and number of services purchases from a multi-service provider: Does age of a relationship matter?
The authors examine the effect of relational constructs (e.g., satisfaction, trust, and affective and calculative commitment) on customer referrals and the number of services purchased, as well as the moderating effect of age of the relationship on these relationships. The research reported, based on data obtained from a large sample of customers of an insurance company, combines archival and survey data. The results provide evidence that supports the moderating effect of relationship age on the relationship between satisfaction, affective and calculative commitment, and the number of services purchased
In black south africans from rural and urban communities, the 4G/5G PAI-1 polymorphism influences PAI-1 activity, but not plasma clot lysis time
Data on genetic and environmental factors influencing PAI-1 levels and their consequent effect on clot lysis in black African populations are limited. We identified polymorphisms in the promoter area of the PAI-1 gene and determined their influence on PAI-1act levels and plasma clot lysis time (CLT). We also describe gene-environment interactions and the effect of urbanisation. Data from 2010 apparently healthy urban and rural black participants from the South African arm of the PURE study were cross-sectionally analysed. The 5G allele frequency of the 4G/5G polymorphism was 0.85. PAI-1act increased across genotypes in the urban subgroup (p = 0.009) but not significantly in the rural subgroup, while CLT did not differ across genotypes. Significant interaction terms were found between the 4G/5G polymorphism and BMI, waist circumference and triglycerides in determining PAI-1act, and between the 4G/5G polymorphism and fibrinogen and fibrinogen gamma prime in determining CLT. The C428T and G429A polymorphisms did not show direct relationships with PAI-1act or CLT but they did influence the association of other environmental factors with PAI-1 act and CLT. Several of these interactions differed significantly between rural and urban subgroups, particularly in individuals harbouring the mutant alleles. In conclusion, although the 4G/5G polymorphism significantly affected PAI-1act, it contributed less than 1% to the PAI-1 act variance. (Central) obesity was the biggest contributor to PAI-1act variance (12.5%). Urbanisation significantly influenced the effect of the 4G/5G polymorphism on PAI-1act as well as gene-environment interactions for the C428T and G429A genotypes in determining PAI-1act and CLT
Temperature and magnetic-field dependence of quantum creep in various high-Tc superconductors
Theoretical investigations of a highly mismatched interface: the case of SiC/Si(001)
Using first principles, classical potentials, and elasticity theory, we
investigated the structure of a semiconductor/semiconductor interface with a
high lattice mismatch, SiC/Si(001). Among several tested possible
configurations, a heterostructure with (i) a misfit dislocation network pinned
at the interface and (ii) reconstructed dislocation cores with a carbon
substoichiometry is found to be the most stable one. The importance of the slab
approximation in first-principles calculations is discussed and estimated by
combining classical potential techniques and elasticity theory. For the most
stable configuration, an estimate of the interface energy is given. Finally,
the electronic structure is investigated and discussed in relation with the
dislocation array structure. Interface states, localized in the heterostructure
gap and located on dislocation cores, are identified
Bone formation rather than inflammation reflects Ankylosing Spondylitis activity on PET-CT: a pilot study
INTRODUCTION: Positron Emission Tomography - Computer Tomography (PET-CT) is an interesting imaging technique to visualize Ankylosing Spondylitis (AS) activity using specific PET tracers. Previous studies have shown that the PET tracers [(18)F]FDG and [(11)C](R)PK11195 can target inflammation (synovitis) in rheumatoid arthritis (RA) and may therefore be useful in AS. Another interesting tracer for AS is [(18)F]Fluoride, which targets bone formation. In a pilot setting, the potential of PET-CT in imaging AS activity was tested using different tracers, with Magnetic Resonance Imaging (MRI) and conventional radiographs as reference. METHODS: In a stepwise approach different PET tracers were investigated. First, whole body [(18)F]FDG and [(11)C](R)PK11195 PET-CT scans were obtained of ten AS patients fulfilling the modified New York criteria. According to the BASDAI five of these patients had low and five had high disease activity. Secondly, an extra PET-CT scan using [(18)F]Fluoride was made of two additional AS patients with high disease activity. MRI scans of the total spine and sacroiliac joints were performed, and conventional radiographs of the total spine and sacroiliac joints were available for all patients. Scans and radiographs were visually scored by two observers blinded for clinical data. RESULTS: No increased [(18)F]FDG and [(11)C](R)PK11195 uptake was noticed on PET-CT scans of the first 10 patients. In contrast, MRI demonstrated a total of five bone edema lesions in three out of 10 patients. In the two additional AS patients scanned with [(18)F]Fluoride PET-CT, [(18)F]Fluoride depicted 17 regions with increased uptake in both vertebral column and sacroiliac joints. In contrast, [(18)F]FDG depicted only three lesions, with an uptake of five times lower compared to [(18)F]Fluoride, and again no [(11)C](R)PK11195 positive lesions were found. In these two patients, MRI detected nine lesions and six out of nine matched with the anatomical position of [(18)F]Fluoride uptake. Conventional radiographs showed structural bony changes in 11 out of 17 [(18)F]Fluoride PET positive lesions. CONCLUSIONS: Our PET-CT data suggest that AS activity is reflected by bone activity (formation) rather than inflammation. The results also show the potential value of PET-CT for imaging AS activity using the bone tracer [(18)F]Fluoride. In contrast to active RA, inflammation tracers [(18)F]FDG and [(11)C](R)PK11195 appeared to be less useful for AS imaging
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