Operations Research for Green Logistics – An Overview of Aspects, Issues, Contributions and Challenges

The worldwide economic growth of the last century has given rise to a vast consumption of goods while globalization has led to large streams of goods all over the world. The production, transportation, storage and consumption of all these goods, however, have created large environmental problems. Today, global warming, created by large scale emissions of greenhouse gasses, is a top environmental concern. Governments, action groups and companies are asking for measures to counter this threat. Operations research has a long tradition in improving operations and especially in reducing costs. In this paper, we present a review that highlights the contribution of operations research to green logistics, which involves the integration of environmental aspects in logistics. We give a sketch of the present and possible developments, focussing on design, planning and control in a supply chain for transportation, inventory of products and facility decisions. While doing this, we also indicate several areas where environmental aspects could be included in OR models for logistics

Prediction of coronary heart disease risk in a general, pre-diabetic, and diabetic population during 10 years of follow-up: Accuracy of the Framingham, SCORE, and UKPDS risk functions - The Hoorn Study

OBJECTIVE - To test the validity of the Framingham, Systematic Coronary Risk Evaluation (SCORE), and UK Prospective Diabetes Study (UKPDS) risk function in the prediction of risk of coronary heart disease (CHD) in populations with normal glucose tolerance (NGT), intermediate hyperglycemia, and type 2 diabetes. RESEARCH DESIGN AND METHODS - Calibration and discrimination of the three prediction models were tested using prospective data for 1,482 Caucasian men and women, 50-75 years of age, who participated in the Hoorn Study. All analyses were stratified by glucose status. RESULTS - During 10 years of follow-up, a total of 197 CHD events, of which 43 were fatal, were observed in this population, with the highest percentage of first CHD events in the diabetic group. The Framingham and UKPDS prediction models overestimated the risk of first CHD event in all glucose tolerance groups. Overall, the prediction models had a low to moderate discriminatory capacity. The SCORE risk function was the best predictor of fatal CHD events in the group with NGT (area under the receiver operating characteristic curve 0.79 [95% CI 0.70-0.87]), whereas the UKPDS performed better in the intermediate hyperglycemia group (0.84 [0.74-0.94]) in the estimation of fatal CHD risk. After exclusion of known diabetic patients, all prediction models had a higher discriminatory ability in the group with diabetes. CONCLUSIONS - The use of the Framingham function for prediction of the first CHD event is likely to overestimate an individual's absolute CHD risk. In CHD prevention, application of the SCORE and UKPDS functions might be useful in the absence of a more valid tool. © 2009 by the American Diabetes Association

Impact of Communicating Familial Risk of Diabetes on Illness Perceptions and Self-Reported Behavioral Outcomes: A randomized controlled trial

OBJECTIVE: To assess the potential effectiveness of communicating familial risk of diabetes on illness perceptions and self-reported behavioral outcomes. RESEARCH DESIGN AND METHODS: Individuals with a family history of diabetes were randomized to receive risk information based on familial and general risk factors (n = 59) or general risk factors alone (n = 59). Outcomes were assessed using questionnaires at baseline, 1 week, and 3 months. RESULTS: Compared with individuals receiving general risk information, those receiving familial risk information perceived heredity to be a more important cause of diabetes (P <0.01) at 1-week follow-up, perceived greater control over preventing diabetes (P <0.05), and reported having eaten more healthily (P = 0.01) after 3 months. Behavioral intentions did not differ between the groups. CONCLUSIONS: Communicating familial risk increased personal control and, thus, did not result in fatalism. Although the intervention did not influence intentions to change behavior, there was some evidence to suggest it increases healthy behavio

Stable hemoglobin concentration with fecal immunochemical test at high temperatures in a Caribbean colorectal cancer screening program

Background and aims: High temperatures may reduce fecal immunochemical test (FIT) positivity and colorectal cancer (CRC) detection sensitivity. We investigated the effect of temperature on hemoglobin concentration [Hb], in the FOB Gold®. Additionally, we examined FIT pick-up, storage, return times and specimen collection. Materials and Methods: In vitro experiments with buffer containing FIT devices, inoculated with Hb-spiked stool. For 7 days, 144 samples were stored in groups of 36 at 4 °C, 22 °C, 30 °C, and 50 °C. Additionally, 54 samples were stored in groups of 18 at 34 °C, 42 °C and 50 °C for 20 h. Paired t-tests and repeated measure ANOVA assessed [Hb] change. Sixty-five screening participants completed a FIT-handling questionnaire. Results: After 7 days, mean [Hb] was stable at 30 °C (0.8 µg Hb/g;95 %CI: −1.5 to 3.1;p = 0.50). For 50 °C, mean [Hb] decreased within 2 days (−21.3 µg Hb/g;95 %CI: −30.2 to −12.5;p &lt; 0.001) and after 20 h (−63.0 µg Hb/g;95 %CI: −88.7 to −37.3;p &lt; 0.001), respectively. All other temperature categories showed significant mean [Hb] increase. Same-day FIT return was reported by 80 %. Eighty-seven percent experienced specimen collection as easy and 33 % kept the FIT refrigerated after collection. Conclusions: The FOB Gold® is suitable for CRC screening in tropical climates. Although most respondents indicated same-day sample return, we recommend avoiding FIT storage above 30 °C for longer than7 days.</p

Endothelial Dysfunction Plays a Key Role in Increasing Cardiovascular Risk in Type 2 Diabetes The Hoorn Study

In the pathogenesis of cardiovascular events, interaction between risk factors has seldom been identified. However, endothelial dysfunction on the one hand and type 2 diabetes mellitus, impaired glucose metabolism (IGM), and insulin resistance on the other may act synergistically (ie, interact) in the development of cardiovascular disease. We therefore investigated the interaction between endothelial dysfunction and type 2 diabetes mellitus, IGM, and insulin resistance with regard to risk of cardiovascular events. In a prospective population-based cohort (n=445; 69 years; 55% women; 23% type 2 diabetes mellitus, 28% IGM [by design]), endothelial dysfunction (brachial artery flow-mediated dilatation), glucose tolerance (oral glucose tolerance test), and insulin sensitivity (homeostasis model assessment for insulin resistance [HOMA2-IR]) were determined. After a median follow-up of 7.6 years, 106 participants had had a cardiovascular event. After adjustments, 1 SD less flow-mediated dilatation was associated with cardiovascular events in type 2 diabetes mellitus (hazard ratio 1.69 [95% confidence interval, 1.14-2.52]) and IGM (1.50 [0.95-2.37]) and among those in the highest HOMA2-IR tertile (1.92 [1.42-2.60]), but not in normal glucose metabolism (0.85 [0.63-1.16]) or among those in the lower 2 HOMA2-IR tertiles combined (0.85 [0.65-1.12]). Interaction between flow-mediated dilatation and type 2 diabetes mellitus, IGM, or insulin resistance was present on an additive (relative excess risk caused by interaction &gt;0) and on a multiplicative scale (P interactio

Stable hemoglobin concentration with fecal immunochemical test at high temperatures in a Caribbean colorectal cancer screening program

Background and aims: High temperatures may reduce fecal immunochemical test (FIT) positivity and colorectal cancer (CRC) detection sensitivity. We investigated the effect of temperature on hemoglobin concentration [Hb], in the FOB Gold®. Additionally, we examined FIT pick-up, storage, return times and specimen collection. Materials and Methods: In vitro experiments with buffer containing FIT devices, inoculated with Hb-spiked stool. For 7 days, 144 samples were stored in groups of 36 at 4 °C, 22 °C, 30 °C, and 50 °C. Additionally, 54 samples were stored in groups of 18 at 34 °C, 42 °C and 50 °C for 20 h. Paired t-tests and repeated measure ANOVA assessed [Hb] change. Sixty-five screening participants completed a FIT-handling questionnaire. Results: After 7 days, mean [Hb] was stable at 30 °C (0.8 µg Hb/g;95 %CI: −1.5 to 3.1;p = 0.50). For 50 °C, mean [Hb] decreased within 2 days (−21.3 µg Hb/g;95 %CI: −30.2 to −12.5;p &lt; 0.001) and after 20 h (−63.0 µg Hb/g;95 %CI: −88.7 to −37.3;p &lt; 0.001), respectively. All other temperature categories showed significant mean [Hb] increase. Same-day FIT return was reported by 80 %. Eighty-seven percent experienced specimen collection as easy and 33 % kept the FIT refrigerated after collection. Conclusions: The FOB Gold® is suitable for CRC screening in tropical climates. Although most respondents indicated same-day sample return, we recommend avoiding FIT storage above 30 °C for longer than7 days.</p

Prolonged QT interval: A tricky diagnosis?

Prolonged heart-rate adjusted QT intervals on the electrocardiogram (ECG) are associated with an increased risk far coronary heart disease and sudden death. However, the diagnosis of the prolonged QT interval is hampered by lack of standards. We studied variations in the prevalence of prolonged QT, based on different common definitions, in a large nonhospitalized population, and compared our results with other studies applying the same definitions. The study population consisted of 2,200 men and 3,366 women participants of the Rotterdam Study, ≤55 years old. The QT interval was computed by our Modular ECG Analysis System (MEANS). Three different formulas to adjust QT for heart rata were used: Bazett's formula (QT(c), a linear regression equation (QT(Ir)), and the QT index (QTI). Prolonged QT occurred frequently in both men and women, and its prevalence increased with age. Women had longer heart-rate adjusted QT intervals than men (mean QT(c) 433 ms vs 422 ms), and mean values for QT(Ir) were lower than for QT(c) (mean QT(Ir) 422 ms in women and 412 ms in men). Prevalence was highest for prolonged QT(Ir) (31% in men and 26% in women) and lowest for prolonged QTI (6% in men and 9% in women). Comparison with other studies applying the same correction formulas showed large discrepancies in prevalence estimates of prolonged QT(c) and QT(Ir), and to a lesser degree of prolonged QTI, possibly due to differences in measurement techniques. Future research is needed to relate QT interval to prognosis, to obtain measurement technique specific reference values of heart-rate adjusted QT measurements, and to obtain age-and sex- specific threshold values for prolonged QT. Such data are needed to use the QT interval with confidence

Quantitative models for reverse logistics

This article surveys the recently emerged field of reverse logistics. The management of return flows induced by the various forms of reuse of products and materials in industrial production processes has received growing attentio

Local Stiffness of the Carotid and Femoral Artery Is Associated With Incident Cardiovascular Events and All-Cause Mortality The Hoorn Study

ObjectivesThis study sought to investigate the association of local and segmental arterial stiffness with incident cardiovascular events and all-cause mortality.BackgroundThe association of different stiffness indices, in particular of carotid, brachial, and femoral stiffness, with cardiovascular disease and mortality is currently unknown.MethodsIn a population-based cohort (n = 579, mean age 67 years, 50% women, 23% with type 2 diabetes [by design]), we assessed local stiffness of carotid, femoral, and brachial arteries (by ultrasonography), carotid-femoral pulse wave velocity (cfPWV), aortic augmentation index, and systemic arterial compliance.ResultsAfter a median follow-up of 7.6 years, 130 participants had a cardiovascular event and 96 had died. The hazard ratios (HRs) (95% confidence intervals [CIs]) per 1 SD for cardiovascular events and all-cause mortality, respectively, were HR: 1.22 (95% CI: 0.95 to 1.56) and 1.51 (95% CI: 1.11 to 2.06) for lower carotid distensibility; HR: 1.19 (95% CI: 1.00 to 1.41) and 1.28 (95% CI: 1.07 to 1.53) for higher carotid elastic modulus; HR: 1.08 (95% CI: 0.88 to 1.31) and 1.43 (95% CI: 1.10 to 1.86) for lower carotid compliance; HR: 1.39 (95% CI: 1.06 to 1.83) and 1.27 (95% CI: 0.90 to 1.79) for lower femoral distensibility; HR: 1.25 (95% CI: 0.96 to 1.63) and 1.47 (95% CI: 1.01 to 2.13) for lower femoral compliance; and HR: 1.56 (95% CI: 1.23 to 1.98) and 1.13 (95% CI: 0.83 to 1.54) for higher cfPWV. These results were adjusted for age, sex, mean arterial pressure, and cardiovascular risk factors. Mutual adjustments for each of the other stiffness indices did not materially change these results. Brachial stiffness, augmentation index, and systemic arterial compliance were not associated with cardiovascular events or mortality.ConclusionsCarotid and femoral stiffness indices are independently associated with incident cardiovascular events and all-cause mortality. The strength of these associations with events may differ per stiffness parameter