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Material requirements planning (MRP) is a basic tool for performing detailed material planning function in the manufacture of component parts and their assembly into finished items. MRP's managerial objective is to provide 'the right part at the right time' to meet the schedules for completed products. However satisfying end customer demands faster with lower inventories implies smarter scheduling which must simultaneously reflect actual capacity conditions. Therefore, the need is to schedule both capacity and materials simultaneously. Since MRP does not consider the availability of capacity resources to schedule production, consequently the schedules so developed are usually capacity infeasible. This paper proposes a three-step procedure to develop capacity feasible material and production schedules in a finite capacity environment. In the first step, an LP model produces capacity feasible but lot size relaxed planned order releases for all end products and assembly components which are then fed into a MRP processor, where a bill of material (BOM) explosion process generates material plans. Finally, these material plans are introduced to another LP model which assures that capacity feasibility is again restored. The mathematical models developed consider restrictions on lot sizes as well as alternative production routings and overtime decisions. A numerical example also is provided and some future research directions are outlined.

Acidic beverages may be involved in regulating the cell proliferation of the gastric mucosa. We therefore analyzed the interaction of Coca-Cola consumption and gastric mucosal proliferation by means of flow cytometry.Sixteen healthy students agreed to participate in this study. All volunteers underwent an oesophagogastroduodenoscopy after a 12-h overnight fast. Endoscopic changes in the gastric mucosa were determined quantitatively. One day later, after a 12-h overnight fast, all volunteers received standard Coca-Cola (200 ml, pH 2.6, 4 degrees C). One hour later all volunteers again underwent oesophagogastroduodenoscopy, to measure gastric mucosal damage. During both the first and the second endoscopy at least four biopsy specimens were taken from the antrum for flow cytometric analysis.The endoscopic analysis showed that there was no difference before and after Coca-Cola consumption. However, the flow cytometric analysis showed that Coca-Cola inhibited the proliferation index and the S phase. Before Coca-Cola consumption G0/G1: 60 (57-62), G2/M: 0.6 (0.2-1), S: 40 (37-42), and PI: 0.40 (0.38-0.43) and after Coca-Cola consumption G0/G1: 70 (60-73), G2/M: 1.9 (1.2-2.5), S: 28 (26-32), and PI: 0.30 (0.27-0.34) the cell population G0/G1 and G2/M phases were significantly increased (P0.0001, 0.0003), and the cell population S and PI phases were significantly low compared with the pre-consumption data (P0.0002, 0.0001).The cell cycle analysis reflects that Coca-Cola inhibits a crucial event in the cell cycle occurring at the G1/S border.

PubMed ID: 26460579, Objectives: The objective of this study is to investigate whether patients with androgenetic alopecia were at risk in terms of urinary system stone disease. Patients and methods: Patients with no baldness (Hamilton-Norwood Scala [HNS] stage I) were categorized as Group I, those with hair loss in the frontal region (HNS stages II, III, IIIa, and IVa) as Group II, those with hair loss in the vertex region (HNS stage III-vertex, V) as Group III and those with hair loss in both vertex and frontal regions (HNS stages IV, Va, VI, and VII) as Group IV. Patients in all groups were compared in terms of presence of stone, and the presence of any association between alopecia and urolithiasis, with common etiological risk factors, was investigated. Results: Three hundred and two male patients were included in the study. The presence of urolithiasis was detected in 28.9% of patients in Group I; 26.5% of Group II; 36.9% of Group III; and 44.4% of Group IV (p = 0.085). Among patients aged under 60, urinary stone disease was detected in 30.8% of patients in Group I; 26.4% of Group II; 41.2% of Group III; and 53.8% of Group IV (p = 0.001). In patients aged over 60, urolithiasis was detected in 12.5% of patients in Group I; 26.9% of Group II; 32.2% of Group III; and 37.8% of Group IV (p = 0.371). Conclusions: We determined a significant correlation between vertex pattern and total alopecia with urolithiasis in patients younger than 60 years old. © 2015 Taylor & Francis.