scispace - formally typeset
Search or ask a question

Showing papers by "Maastricht University published in 2001"


Journal ArticleDOI
TL;DR: In this paper, the authors investigate retailer-consumer relationships, and show that different relationship marketing tactics have a differential impact on consumer perceptions of a retailer's relationship investment, and demonstrate that perceived relationship investment affects relationship quality.
Abstract: This research, investigating retailer-consumer relationships, has three distinct intended contributions: (1) It shows that different relationship marketing tactics have a differential impact on consumer perceptions of a retailer’s relationship investment; (2) it demonstrates that perceived relationship investment affects relationship quality, ultimately leading to behavioral loyalty; and (3) it reveals that the effect of perceived relationship investment on relationship quality is contingent on a consumer’s product category involvement and proneness to engage in retail relationships. The authors empirically cross-validate the underlying conceptual model by studying six consumer samples in a three-country, transatlantic, comparative survey that investigates two industries.

2,113 citations


Journal ArticleDOI
TL;DR: In this article, the authors use the example of a transition to a low emission energy supply in the Netherlands to argue that transition management provides a basis for coherence and consistency in public policy and can be the spur to sustainable development.
Abstract: Transitions are transformation processes in which society changes in a fundamental way over a generation or more. Although the goals of a transition are ultimately chosen by society, governments can play a role in bringing about structural change in a stepwise manner. Their management involves sensitivity to existing dynamics and regular adjustment of goals to overcome the conflict between long‐term ambition and short‐term concerns. This article uses the example of a transition to a low emission energy supply in the Netherlands to argue that transition management provides a basis for coherence and consistency in public policy and can be the spur to sustainable development.

1,913 citations


Journal ArticleDOI
TL;DR: In this paper, the authors found that risedronate increases bone mineral density in elderly women, but whether it prevents hip fracture is not known, and the women were randomly assigned to receive treatment with either oral risingronate (2.5 or 5.0 mg) or placebo for three years.
Abstract: Background Risedronate increases bone mineral density in elderly women, but whether it prevents hip fracture is not known. Methods We studied 5445 women 70 to 79 years old who had osteoporosis (indicated by a T score for bone mineral density at the femoral neck that was more than 4 SD below the mean peak value in young adults [–4] or lower than –3 plus a nonskeletal risk factor for hip fracture, such as poor gait or a propensity to fall) and 3886 women at least 80 years old who had at least one nonskeletal risk factor for hip fracture or low bone mineral density at the femoral neck (T score, lower than –4 or lower than –3 plus a hip-axis length of 11.1 cm or greater). The women were randomly assigned to receive treatment with oral risedronate (2.5 or 5.0 mg daily) or placebo for three years. The primary end point was the occurrence of hip fracture. Results Overall, the incidence of hip fracture among all the women assigned to risedronate was 2.8 percent, as compared with 3.9 percent among those assigned t...

1,719 citations


Posted Content
TL;DR: A theory of reciprocity for extensive games in which the sequential structure of a strategic situation is made explicit is developed and a general equilibrium existence result is proved.
Abstract: Many experimental studies indicate that people are motivated by reciprocity. Rabin (1993) develops techniques for incorporating such concerns into game theory and economics. His model, however, does not fare well when applied to situations with an interesting dynamic structure (like many experimental games), because it is developed for normal form games in which information about the sequential structure of a strategic situation is suppressed. In this paper we develop a theory of reciprocity for extensive games in which the sequential structure of a strategic situation is made explicit. We propose a new solution concept— sequential reciprocity equilibrium—which is applicable to extensive games, and we prove a general equilibrium existence result. The model is applied in several examples, including some well known experimental games like the Ultimatum game and the Sequential Prisoners’ Dilemma. (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract was borrowed from another version of this item.) (This abstract wa (This abstract was borrowed from another version of this item.)

1,518 citations


Journal ArticleDOI
TL;DR: The results indicate that chronic vascular insufficiency and, possibly, insufficient Vegf-dependent neuroprotection lead to the select degeneration of motor neurons.
Abstract: Hypoxia stimulates angiogenesis through the binding of hypoxia-inducible factors to the hypoxia-response element in the vascular endothelial growth factor (Vegf) promotor. Here, we report that deletion of the hypoxia-response element in the Vegf promotor reduced hypoxic Vegf expression in the spinal cord and caused adult-onset progressive motor neuron degeneration, reminiscent of amyotrophic lateral sclerosis. The neurodegeneration seemed to be due to reduced neural vascular perfusion. In addition, Vegf165 promoted survival of motor neurons during hypoxia through binding to Vegf receptor 2 and neuropilin 1. Acute ischemia is known to cause nonselective neuronal death. Our results indicate that chronic vascular insufficiency and, possibly, insufficient Vegf-dependent neuroprotection lead to the select degeneration of motor neurons.

1,029 citations


Journal ArticleDOI
TL;DR: Multifaceted professional interventions and organizational interventions that facilitate structured and regular review of patients were effective in improving the process of care.
Abstract: OBJECTIVE —To review the effectiveness of interventions targeted at health care professionals and/or the structure of care in order to improve the management of diabetes in primary care, outpatient, and community settings. RESEARCH DESIGN AND METHODS —A systematic review of controlled trials evaluating the effectiveness of interventions targeted at health care professionals and aimed at improving the process of care or patient outcomes for patients with diabetes was performed. Standard search methods of the Cochrane Effective Practice and Organization of Care Group were used. RESULTS —A total of 41 studies met the inclusion criteria. The studies identified were heterogeneous in terms of interventions, participants, settings, and reported outcomes. In all studies, the interventions were multifaceted. The interventions were targeted at health care professionals only in 12 studies, at the organization of care only in 9 studies, and at both in 20 studies. Complex professional interventions improved the process of care, but the effect on patient outcomes remained less clear because such outcomes were rarely assessed. Organizational interventions that facilitated the structured and regular review of patients also showed a favorable effect on process measures. Complex interventions in which patient education was added and/or the role of a nurse was enhanced led to improvements in patient outcomes as well as the process of care. CONCLUSIONS —Multifaceted professional interventions and organizational interventions that facilitate structured and regular review of patients were effective in improving the process of care. The addition of patient education to these interventions and the enhancement of the role of nurses in diabetes care led to improvements in patient outcomes and the process of care.

1,019 citations


Journal ArticleDOI
TL;DR: Evidence for the continuity of psychotic symptoms with normal experiences is reviewed, focusing on the symptoms of hallucinations and delusions, and the theoretical and treatment implications of such a continuum are discussed.

922 citations


Journal ArticleDOI
TL;DR: The goal of assessment in medical education remains the development of reliable measurements of student performance which, as well as having predictive value for subsequent clinical competence, also have a formative, educational role.

901 citations


Journal ArticleDOI
01 Jul 2001
TL;DR: The authors examined the relation between educational mismatches and skill mismatches, and found that skill mismatch is much better predictors of job satisfaction and on-the-job search than are educational mismatch.
Abstract: Education-job mismatches are reported to have serious effects on wages and other labour market outcomes. Such results are often cited in support of assignment theory, but can also be explained by institutional and human capital models. To test the assignment explanation, we examine the relation between educational mismatches and skill mismatches. In line with earlier research, educational mismatches affect wages strongly. Contrary to the assumptions of assignment theory, this effect is not explained by skill mismatches. Conversely, skill mismatches are much better predictors of job satisfaction and on-the-job search than are educational mismatches.

874 citations


Journal ArticleDOI
TL;DR: It is concluded that the most likely mechanism for the reduction in fat oxidation during high‐intensity exercise is a downregulation of carnitine palmitoyltransferase I, either by this marked decline in free carnitines availability or by a decrease in intracellular pH.
Abstract: 1. Contemporary stable isotope methodology was applied in combination with muscle biopsy sampling to accurately quantify substrate utilisation and study the regulation of muscle fuel selection during exercise. 2. Eight cyclists were studied at rest and during three consecutive 30 min stages of exercise at intensities of 40, 55 and 75 % maximal workload (W(max)). A continuous infusion of [U-(13)C]palmitate and [6,6-(2)H(2)]glucose was administered to determine plasma free fatty acid (FFA) oxidation and estimate plasma glucose oxidation, respectively. Biopsy samples were collected before and after each exercise stage. 3. Muscle glycogen and plasma glucose oxidation rates increased with every increment in exercise intensity. Whole-body fat oxidation increased to 32 +/- 2 kJ min(-1) at 55 % W(max), but declined at 75 % W(max) (19 +/- 2 kJ min(-1)). This decline involved a decrease in the oxidation rate of both plasma FFA and triacylglycerol fat sources (sum of intramuscular plus lipoprotein-derived triacylglycerol), and was accompanied by increases in muscle pyruvate dehydrogenase complex activation and acetylation of the carnitine pool, resulting in a decline in muscle free carnitine concentration. 4. We conclude that the most likely mechanism for the reduction in fat oxidation during high-intensity exercise is a downregulation of carnitine palmitoyltransferase I, either by this marked decline in free carnitine availability or by a decrease in intracellular pH.

789 citations


Journal ArticleDOI
TL;DR: Coronary pressure–derived fractional flow reserve (FFR) is an invasive index of stenosis severity that is a reliable substitute for noninvasive stress testing and identifies stenoses with hemodynamic significance.
Abstract: Background—PTCA of a coronary stenosis without documented ischemia at noninvasive stress testing is often performed, but its benefit is unproven. Coronary pressure–derived fractional flow reserve (FFR) is an invasive index of stenosis severity that is a reliable substitute for noninvasive stress testing. A value of 0.75 identifies stenoses with hemodynamic significance. Methods and Results—In 325 patients for whom PTCA was planned and who did not have documented ischemia, FFR of the stenosis was measured. If FFR was >0.75, patients were randomly assigned to deferral (deferral group; n=91) or performance (performance group; n=90) of PTCA. If FFR was <0.75, PTCA was performed as planned (reference group; n=144). Clinical follow-up was obtained at 1, 3, 6, 12, and 24 months. Event-free survival was similar between the deferral and performance groups (92% versus 89% at 12 months and 89% versus 83% at 24 months) but was significantly lower in the reference group (80% at 12 months and 78% at 24 months). In addi...

Journal ArticleDOI
TL;DR: In this paper, the effect of the Kirsten ras (Ki-ras) tumour genotype and outcome of patients with colorectal cancer was investigated using a multivariate analysis.
Abstract: Researchers worldwide with information about the Kirsten ras (Ki-ras) tumour genotype and outcome of patients with colorectal cancer were invited to provide that data in a schematized format for inclusion in a collaborative database called RASCAL (The Kirsten ras incolorectal-cancer collaborative group). Our results from 2721 such patients have been presented previously and for the first time in any common cancer, showed conclusively that different gene mutations have different impacts on outcome, even when the mutations occur at the same site on the genome. To explore the effect of Ki-ras mutations at different stages of colorectal cancer, more patients were recruited to the database, which was reanalysed when information on 4268 patients from 42 centres in 21 countries had been entered. After predetermined exclusion criteria were applied, data on 3439 patients were entered into a multivariate analysis. This found that of the 12 possible mutations on codons 12 and 13 of Kirsten ras, only one mutation on codon 12, glycine to valine, found in 8.6% of all patients, had a statistically significant impact on failure-free survival (P=0.004, HR 1.3) and overall survival (P=0.008, HR 1.29). This mutation appeared to have a greater impact on outcome in Dukes' C cancers (failure-free survival, P=0.008, HR 1.5, overall survival P=0.02, HR 1.45) than in Dukes' B tumours (failure-free survival, P=0.46, HR 1.12, overall survival P=0.36, HR 1.15). Ki-ras mutations may occur early in the development of pre-cancerous adenomas in the colon and rectum. However, this collaborative study suggests that not only is the presence of a codon 12 glycine to valine mutation important for cancer progression but also that it may predispose to more aggressive biological behaviour in patients with advanced colorectal cancer. ⌐ 2001 Cancer Research Campaign.

Journal ArticleDOI
TL;DR: Atrial fibrillation is a ubiquitous yet diverse cardiac arrhythmia whose incidence increases with age; with most forms of cardiac and some pulmonary diseases; and with a number of metabolic, toxic, endocrine, or genetic abnormalities.
Abstract: Atrial fibrillation (AF) is a ubiquitous yet diverse cardiac arrhythmia whose incidence increases with age; with most forms of cardiac and some pulmonary diseases; and with a number of metabolic, toxic, endocrine, or genetic abnormalities.1 2 Classification of clinical AF subtypes can be achieved on the basis of the ease by which episodes of the arrhythmia terminate as follows3 : “Paroxysmal” AF refers to episodes that generally stop spontaneously after no more than a few days. “Persistent” AF occurs less frequently than paroxysmal AF and, rather than self-terminating, requires cardioversion to restore sinus rhythm. “Permanent” AF cannot be converted to sinus rhythm. These terms apply strictly to chronic AF, because a single episode of the arrhythmia cannot be fully categorized. Although there are some mixed patterns, they generally derive from physician impatience for early cardioversion or from pragmatic clinical considerations (eg, to avoid thrombus formation or hemodynamic decompensation). Patients initially presenting with paroxysmal AF often progress to longer, non–self-terminating bouts. An exception may be paroxysmal AF during intense vagotonia. Moreover, AF initially responsive to pharmacological or electrical cardioversion tends to become resistant and cannot then be converted to sinus rhythm. To some extent, the failure of the physician to suggest or the patient to accept further cardioversion attempts may lead to diagnosis of “permanent” AF. Thus, the “point of no return” may be determined by true pathophysiological abnormalities or may merely be an artifact of clinical pragmatism. Effective prevention is essential in managing this arrhythmia whose occurrence is widespread, progression is relentless, and morbidity and mortality are significant. To focus on means for prevention necessitates considering both clinical risk factors and pathophysiology. AF derives from a complex continuum predisposing factors, summarized in Table 1⇓. In the West, about 5% of the population >65 years of age …

Journal ArticleDOI
15 Nov 2001-Spine
TL;DR: In this paper, the authors compare national clinical guidelines on low back pain on 11 different countries published from 1994 until 2000 and find that diagnostic and therapeutic recommendations were generally similar. But there were discrepancies for recommendations regarding exercise therapy, spinal manipulation, muscle relaxants, and patient information.
Abstract: Study design Descriptive study. Objectives To compare national clinical guidelines on low back pain. Summary of background data To rationalize the management of low back pain, clinical guidelines have been issued in various countries around the world. Given that the available scientific evidence is the same, irrespective of the country, one would expect these guidelines to include more or less similar recommendations regarding diagnosis and treatment. Methods Guidelines were included that met the following criteria: the target group consisted of primary care health professionals, and the guideline was published in English, German, or Dutch. Only one guideline per country was included: the one most recently published. Results Clinical guidelines from 11 different countries published from 1994 until 2000 were included in this review. The content of the guidelines appeared to be quite similar regarding the diagnostic classification (diagnostic triage) and the use of diagnostic and therapeutic interventions. Consistent features were the early and gradual activation of patients, the discouragement of prescribed bed rest, and the recognition of psychosocial factors as risk factors for chronicity. However, there were discrepancies for recommendations regarding exercise therapy, spinal manipulation, muscle relaxants, and patient information. Conclusion The comparison of clinical guidelines for the management of low back pain showed that diagnostic and therapeutic recommendations were generally similar. Updates of the guidelines are planned in most countries, although so far produced only in the United Kingdom. However, new evidence may lead to stronger conclusions and enable future guidelines to become even more concordant.

Journal ArticleDOI
TL;DR: The observed expression patterns suggest a tight regulation of the expression of bone matrix regulatory proteins during human atherogenesis, which might suggest a regulatory role of these proteins not only in osteoclastogenesis but also in atherosclerotic calcification.
Abstract: In the present study, we examined the expression of regulators of bone formation and osteoclastogenesis in human atherosclerosis because accumulating evidence suggests that atherosclerotic calcification shares features with bone calcification. The most striking finding of this study was the constitutive immunoreactivity of matrix Gla protein, osteocalcin, and bone sialoprotein in nondiseased aortas and the absence of bone morphogenetic protein (BMP)-2, BMP-4, osteopontin, and osteonectin in nondiseased aortas and early atherosclerotic lesions. When atherosclerotic plaques demonstrated calcification or bone formation, BMP-2, BMP-4, osteopontin, and osteonectin were upregulated. Interestingly, this upregulation was associated with a sustained immunoreactivity of matrix Gla protein, osteocalcin, and bone sialoprotein. The 2 modulators of osteoclastogenesis (osteoprotegerin [OPG] and its ligand, OPGL) were present in the nondiseased vessel wall and in early atherosclerotic lesions. In advanced calcified lesions, OPG was present in bone structures, whereas OPGL was only present in the extracellular matrix surrounding calcium deposits. The observed expression patterns suggest a tight regulation of the expression of bone matrix regulatory proteins during human atherogenesis. The expression pattern of both OPG and OPGL during atherogenesis might suggest a regulatory role of these proteins not only in osteoclastogenesis but also in atherosclerotic calcification.

Journal ArticleDOI
TL;DR: The biology of MMPs is described and the central role of the plasminogen system as an important activator of M MPs in the remodeling process after myocardial infarction is speculated on.
Abstract: Increased activity of matrix metalloproteinases (MMPs) has been implicated in numerous disease processes, including tumor growth and metastasis, arthritis, and periodontal disease. It is now becoming increasingly clear that extracellular matrix degradation by MMPs is also involved in the pathogenesis of cardiovascular disease, including atherosclerosis, restenosis, dilated cardiomyopathy, and myocardial infarction. Administration of synthetic MMP inhibitors in experimental animal models of these cardiovascular diseases significantly inhibits the progression of, respectively, atherosclerotic lesion formation, neointima formation, left ventricular remodeling, pump dysfunction, and infarct healing. This review focuses on the role of MMPs in cardiovascular disease, in particular myocardial infarction and the subsequent progression to heart failure. MMPs, which are present in the myocardium and capable of degrading all the matrix components of the heart, are the driving force behind myocardial matrix remodeling. The recent finding that acute pharmacological inhibition of MMPs or deficiency in MMP-9 attenuates left ventricular dilatation in the infarcted mouse heart led to the proposal that MMP inhibitors could be used as a potential therapy for patients at risk for the development of heart failure after myocardial infarction. Although these promising results encourage the design of clinical trials with MMP inhibitors, there are still several unresolved issues. This review describes the biology of MMPs and discusses new insights into the role of MMPs in several cardiovascular diseases. Attention will be paid to the central role of the plasminogen system as an important activator of MMPs in the remodeling process after myocardial infarction. Finally, we speculate on the use of MMP inhibitors as potential therapy for heart failure.

Journal ArticleDOI
TL;DR: In this article, the effect of customer satisfaction with three service components on value perception and overall satisfaction was measured, and a strong positive effect of overall satisfaction on the intention to continue using the portal was found.
Abstract: The commercial importance of e‐services, accessed via Internet or mobile phone, grows steadily. There is a clear need to develop a better understanding of how consumers evaluate these services and develop e‐loyalty. An empirical study of an Internet portal was tied in with extant theories about service quality, customer satisfaction and loyalty. Data were collected by means of an on‐line survey. The effect of customer satisfaction with three service components on value perception and overall satisfaction was measured. Customers’ overall satisfaction was influenced by their satisfaction with the core service, supplementary services and the user interface. A strong positive effect of overall satisfaction on the intention to continue using the portal was found. Noteworthy was the predominant effect of satisfaction with supplementary services on value perception. No significant direct effects were found of satisfaction with the user interface on value perception. Some implications as well as future research directions are provided.

Journal ArticleDOI
TL;DR: In this article, the effects of fear arousal on precautionary motivation and action are reviewed and it seems likely that fear arousal is less important in motivating precautionary action than perceptions of action effectiveness and self-efficacy.
Abstract: Research into the effects of fear-arousal on precautionary motivation and action is reviewed. Current models do not adequately distinguish between emotional (i.e., fear arousal) and cognitive (i.e., threat perception) responses to fear appeals and, in general, are not well supported. Evidence suggesting that (i) coping appraisals are more powerful predictors of precautionary action than threat perception and that (ii) fear control processes may interfere with precautionary motivation, recommends cautious and limited use of fear appeals in health promotion. It seems likely that fear arousal is less important in motivating precautionary action than perceptions of action effectiveness and self-efficacy. Moreover, perceived personal relevance may be critical to the emotional and cognitive impact of threat information. Available findings are summarised in the form of a process model that highlights the potential complexity of fear arousal effects. Sequential measurement of fear arousal, other than by ...

Journal ArticleDOI
TL;DR: The results of this study strongly indicate that transmission of resistant clones and resistance plasmids of E. coli from poultry to humans commonly occurs.
Abstract: The prevalence of resistance in enterococci to antibiotics, commonly used for therapy in poultry or as antimicrobial growth promoters (AMGPs), was determined in faecal samples of two chicken populations: broilers in which antibiotic and AMGP use is common and laying-hens with a low antibiotic usage. In addition faecal samples were examined from three human populations: broiler farmers, laying-hen farmers and poultry slaughterers. MICs of an extended panel of antibiotics for a randomly chosen gentamicin- or vancomycin-resistant enterococcal isolate from each faecal specimen were also determined. The prevalence of resistance for all antibiotics tested was higher in broilers than in laying-hens. Resistance in faecal enterococci of broiler farmers was for nearly all antibiotics higher than those observed in laying-hen farmers and poultry slaughterers. The overall resistance in broilers was correlated with the resistance in broiler farmers and in poultry slaughterers. No correlation between the results obtained in the laying-hens with any of the other populations was found. The 27 gentamicin-resistant isolates all showed high-level resistance to gentamicin and two of these isolates, both Enterococcus faecium, were resistant to all antibiotics tested, except vancomycin. The 73 vancomycin-resistant enterococci (VRE) isolated from the five populations belonged to four different species and in all isolates the vanA gene cluster was detected by blot hybridization. The pulsed-field gel electrophoresis (PFGE) patterns of these vancomycin-resistant enterococci were quite heterogeneous, but Enterococcus hirae isolates with the same or a closely related PFGE pattern were isolated at two farms from the broiler farmer and from broilers. Molecular characterization of vanA-containing transposons of these isolates showed that similar transposon types, predominantly found in poultry, were present. Moreover, similar vanA elements were not only found in isolates with the same PFGE pattern but also in other VRE isolated from both humans and chickens. The results of this study suggest transmission of resistance in enterococci from animals to man. For VRE this might be clonal transmission of animal strains, but transposon transfer seems to occur more commonly.

Journal ArticleDOI
TL;DR: In this paper, the authors investigate the impact of organizational reputation, relative advantage, and perceived risk on perceived service quality, trust and behavioral intentions of customers towards adopting e-services.
Abstract: So far, the term e‐commerce has been primarily associated with communicating the brand and/or enabling sales transactions. However, the next vista for companies operating in the virtual marketplace seems to be e‐service or, delivering value‐added, interactive services to customers. This e‐business function has been left virtually unexplored in the services research literature. In this article, an attempt is made to investigate the impact of organizational reputation, relative advantage, and perceived risk on perceived service quality, trust and behavioral intentions of customers towards adopting e‐services. In the context of an electronic travel service, hypotheses on the relationships between aforementioned variables are investigated by means of an experimental study. The results suggest that the three factors have a significant main effect on the customers’ attitude and behavior towards e‐service. The only exception is that relative advantage does not appear to have a significant impact on customer trust. The results also show that organizational reputation and perceived risk have a combined effect: a good organizational reputation impacts the effect of perceived risk on the three dependent variables. Finally, the three factors appeared to be evenly important in the forming of customers’ attitude and behavior. Again, the only exception is that organizational reputation and perceived risk appear to be more important in terms of trust than relative advantage.

Journal ArticleDOI
TL;DR: There is abundant evidence that the proportion of energy derived from fat during exercise is higher in women than in men, and this finding seems counterintuitive, as percentage body fat is increased in women.
Abstract: Women generally have a higher percentage of body fat than men. Also, women store more fat in the gluteal-femoral region, whereas men store more fat in the visceral (abdominal) depot. This review focuses on differences in regional fatty acid storage, mobilization and oxidation that may contribute to gender-related differences in body fat distribution. There are pronounced regional differences in the regulation of regional fatty acid metabolism between men and women. Firstly, there is evidence that in vivo, catecholamine mediated leg free fatty acid release is lower in women than in men, whereas free fatty acid release from the upper body depots is comparable. These data correspond to in-vitro adipose tissue biopsy data, which indicate a more pronounced difference in catecholamine mediated lipolysis between upper body and lower body fat depots in women than in men. Secondly, free fatty acid release by the upper body subcutaneous fat depots is higher in men than in women, indicating a higher resistance to the antilipolytic effect of meal ingestion in the upper body fat depots in men. Thirdly, there are indications that basal fat oxidation (adjusted for fat free mass) is lower in females as compared to males, thereby contributing to a higher fat storage in women. Finally, postprandial fat storage may be higher in subcutaneous adipose tissue in women than in men, whereas storage in visceral adipose tissue has been hypothesized to be higher in men. All the above differences may play a role in the variation in net regional fat storage between men and women, but the number of in-vivo studies on gender-related differences in fatty acid metabolism is very limited and most findings require confirmation. Furthermore, there is abundant evidence that the proportion of energy derived from fat during exercise is higher in women than in men. With respect to total body fat, this finding seems counterintuitive, as percentage body fat is increased in women. Further studies are necessary to investigate the significance of differences in exercise-induced fat oxidation on 24-h fat balance.

Posted Content
TL;DR: In this article, the authors developed a framework for testing discrete complementarities in innovation policy using European data on obstacles to innovation and proposed a discrete test of supermodularity in innovation policies leading to a number of inequality constraints.
Abstract: This Paper develops a framework for testing discrete complementarities in innovation policy using European data on obstacles to innovation. We propose a discrete test of supermodularity in innovation policy leading to a number of inequality constraints. We apply our test to two types of innovation decisions: to innovate or not, and if so, by how much. We find that industries display a considerable amount of complementarity, with some industries being complementary across all obstacles. We also find that the lack of internal human capital (skilled personnel) is complementary to all the other obstacles in almost all industries. In this sense, our results suggest that internal human capital is key to any innovation policy, insofar that it is complementary to all the other factors that might hamper innovation activities.

Journal ArticleDOI
TL;DR: This paper proposes possible mechanisms to explain the phenomenon in which cells die from excessive sensitivity to small single doses of ionizing radiation but remain more resistant (per unit dose) to larger single doses.
Abstract: Purpose: To retain cell viability, mammalian cells can increase damage repair in response to excessive radiation-induced injury. The adaptive response to small radiation doses is an example of this induced resistance and has been studied for many years, particularly in human lymphocytes. This review focuses on another manifestation of actively increased resistance that is of potential interest for developing improved radiotherapy, specifically the phenomenon in which cells die from excessive sensitivity to small single doses of ionizing radiation but remain more resistant (per unit dose) to larger single doses. In this paper, we propose possible mechanisms to explain this phenomenon based on our data accumulated over the last decade and a review of the literature. Conclusion: Typically, most cell lines exhibit hyper-radiosensitivity (HRS) to very low radiation doses (<10 cGy) that is not predicted by back-extrapolating the cell survival response from higher doses. As the dose is increased above about 30 cGy, there is increased radioresistance (IRR) until at doses beyond about 1 Gy, radioresistance is maximal, and the cell survival follows the usual downward-bending curve with increasing dose. The precise operational and activational mechanism of the process is still unclear, but we propose two hypotheses. The greater amount of injury produced by larger doses either (1) is above a putative damage-sensing threshold for triggering faster or more efficient DNA repair or (2) causes changes in DNA structure or organization that facilitates constitutive repair. In both scenarios, this enhanced repair ability is decreased again on a similar time scale to the rate of removal of DNA damage.

Journal ArticleDOI
TL;DR: A V-like relationship between mortality and temperature is found, with an optimum temperature value of 16.5 degrees C for total mortality, cardiovascular mortality, respiratory mortality, and mortality among those [Greater and equal to] 65 year of age, and the elderly were most effected by extreme heat.
Abstract: We conducted the study described in this paper to investigate the impact of ambient temperature on mortality in the Netherlands during 1979-1997, the impact of heat waves and cold spells on mortality in particular, and the possibility of any heat wave- or cold spell-induced forward displacement of mortality. We found a V-like relationship between mortality and temperature, with an optimum temperature value (e.g., average temperature with lowest mortality rate) of 16.5 degrees C for total mortality, cardiovascular mortality, respiratory mortality, and mortality among those [Greater and equal to] 65 year of age. For mortality due to malignant neoplasms and mortality in the youngest age group, the optimum temperatures were 15.5 degrees C and 14.5 degrees C, respectively. For temperatures above the optimum, mortality increased by 0.47, 1.86, 12.82, and 2.72% for malignant neoplasms, cardiovascular disease, respiratory diseases, and total mortality, respectively, for each degree Celsius increase above the optimum in the preceding month. For temperatures below the optimum, mortality increased 0.22, 1.69, 5.15, and 1.37%, respectively, for each degree Celsius decrease below the optimum in the preceding month. Mortality increased significantly during all of the heat waves studied, and the elderly were most effected by extreme heat. The heat waves led to increases in mortality due to all of the selected causes, especially respiratory mortality. Average total excess mortality during the heat waves studied was 12.1%, or 39.8 deaths/day. The average excess mortality during the cold spells was 12.8% or 46.6 deaths/day, which was mostly attributable to the increase in cardiovascular mortality and mortality among the elderly. The results concerning the forward displacement of deaths due to heat waves were not conclusive. We found no cold-induced forward displacement of deaths.

Journal ArticleDOI
TL;DR: In this article, the reliability and validity of the Self-Efficacy Questionnaire for Children (SEQ-C) in a sample of young adolescents (N = 330) was examined.
Abstract: The current study examined the reliability and validity of the Self-Efficacy Questionnaire for Children (SEQ-C) in a sample of young adolescents (N = 330). Factor analysis of the SEQ-C revealed three factors that were in keeping with the intended subscales: social self-efficacy, academic self-efficacy, and emotional self-efficacy. Furthermore, results showed that the SEQ-C has satisfactory internal consistency. Finally, SEQ-C scores correlated in a theoretically meaningful way with a measure of depression. That is, the lower children's SEQ-C scores, the higher their level of depression. Possible applications of the SEQ-C are briefly discussed.

Journal ArticleDOI
TL;DR: It is shown that platelets lacking GPVI can not activate integrins and consequently fail to adhere to and aggregate on fibrillar as well as soluble collagen, and that GPVI plays the central role in platelet‐collagen interactions by activating different adhesive receptors, including α2β1 integrin.
Abstract: Platelet adhesion on and activation by components of the extracellular matrix are crucial to arrest post-traumatic bleeding, but can also harm tissue by occluding diseased vessels. Integrin alpha2beta1 is thought to be essential for platelet adhesion to subendothelial collagens, facilitating subsequent interactions with the activating platelet collagen receptor, glycoprotein VI (GPVI). Here we show that Cre/loxP-mediated loss of beta1 integrin on platelets has no significant effect on the bleeding time in mice. Aggregation of beta1-null platelets to native fibrillar collagen is delayed, but not reduced, whereas aggregation to enzymatically digested soluble collagen is abolished. Furthermore, beta1-null platelets adhere to fibrillar, but not soluble collagen under static as well as low (150 s(-1)) and high (1000 s(-1)) shear flow conditions, probably through binding of alphaIIbbeta3 to von Willebrand factor. On the other hand, we show that platelets lacking GPVI can not activate integrins and consequently fail to adhere to and aggregate on fibrillar as well as soluble collagen. These data show that GPVI plays the central role in platelet-collagen interactions by activating different adhesive receptors, including alpha2beta1 integrin, which strengthens adhesion without being essential.

Journal ArticleDOI
14 Feb 2001-JAMA
TL;DR: In this paper, the authors examined the association between breast cancer and total and specific fruit and vegetable group intakes using standardized exposure definitions and concluded that fruit and vegetables consumption during adulthood is not significantly associated with reduced breast cancer risk.
Abstract: Context: Some epidemiologic studies suggest that elevated fruit and vegetable consumption is associated with a reduced risk of breast cancer. However, most have been case-control studies in which recall and selection bias may influence the results. Additionally, publication bias may have influenced the literature on associations for specific fruit and vegetable subgroups. Objective: To examine the association between breast cancer and total and specific fruit and vegetable group intakes using standardized exposure definitions. Data Sources/Study Selection: Eight prospective studies that had at least 200 incident breast cancer cases, assessed usual dietary intake, and completed a validation study of the diet assessment method or a closely related instrument were included in these analyses. Data Extraction: Using the primary data from each of the studies, we calculated study-specific relative risks (RRs) that were combined using a random-effects model. Data Synthesis: The studies included 7377 incident invasive breast cancer cases occurring among 351825 women whose diet was analyzed at baseline. For comparisons of the highest vs lowest quartiles of intake, weak, nonsignificant associations were observed for total fruits (pooled multivariate RR, 0.93; 95% confidence interval [CI], 0.86-1.00; P for trend = .08), total vegetables (RR, 0.96; 95% CI, 0.89-1.04; P for trend = .54), and total fruits and vegetables (RR, 0.93; 95% CI, 0.86-1.00; P for trend = .12). No additional benefit was apparent in comparisons of the highest and lowest deciles of intake. No associations were observed for green leafy vegetables, 8 botanical groups, and 17 specific fruits and vegetables. Conclusion: These results suggest that fruit and vegetable consumption during adulthood is not significantly associated with reduced breast cancer risk.

Journal ArticleDOI
TL;DR: A staining protocol is presented combining ORO with immunofluorescence that permits examination of ORO-stained lipid droplets in skeletal muscle sections together with multiple staining of other immunodetectable proteins present in skeletal Muscle by quantitative fluorescence microscopy.
Abstract: The objective of the present study was to develop a stain permitting automated quantification of myocellular lipid depositions in skeletal muscle sections together with immunolocalisation of other myocellular constituents by fluorescence microscopy. Lipid droplets were detected in skeletal muscle by oil red O (ORO). Conventional ORO was modified to diminish background staining, prevent crystallisation of ORO and to optimise lipid retention in cryosections. These modifications resulted in a punctate staining of lipid droplets, rather than the somewhat diffuse staining by conventional ORO. Small cavities in muscle sections (like the lumen of small blood vessels) lack ORO when using the protocol presented here. In addition a staining protocol is presented combining ORO with immunofluorescence. This combination permits multiple staining studies in the same section. Thus, lipid droplets can be studied together with immunolabelling of proteins involved in lipid handling and metabolism. This will extend our knowledge on the subcellular localisation of lipid handling proteins (i.e. enzymes and fatty acid transporting proteins) in relation to the localisation of lipid depositions. In conclusion, the protocol presented here permits examination of ORO-stained lipid droplets in skeletal muscle sections together with multiple staining of other immunodetectable proteins present in skeletal muscle by quantitative fluorescence microscopy.

Journal ArticleDOI
TL;DR: It is shown that the external validity of exposure in vivo also extends to the subgroup of chronic low back pain patients who report substantial fear of movement/(re)injury, and in half of the cases an increase in pain control.

Journal ArticleDOI
TL;DR: In this article, a two-wave panel study was carried out to examine reciprocal relationships between job characteristics and work-related psychological well-being, and the results primarily supported the hypothesis that Time 1 job characteristics influence Time 2 psychological wellbeing.
Abstract: This article describes a two-wave panel study which was carried out to examine reciprocal relationships between job characteristics and work-related psychological well-being. Hypotheses were tested in a sample of 261 health care professionals using structural equation modelling (LISREL 8). Controlling for gender, age, and negative affectivity, the results primarily supported the hypothesis that Time 1 job characteristics influence Time 2 psychological well-being. More specifically, Time 2 job satisfaction was determined by Time 1 job demands and workplace social support, respectively. Furthermore, there was also some preliminary but weak evidence for reversed cross-lagged effects since Time 1 emotional exhaustion seemed to be the causal dominant factor with respect to Time 2 (perceived) job demands. In conclusion, this study builds on earlier cross-sectional and longitudinal findings by eliminating confounding factors and diminishing methodological deficiencies. Empirical support for the influence of job characteristics on psychological well-being affirms what several theoretical models have postulated to be the causal ordering among job characteristics and work-related psychological well-being.