Ιν τηισ παπερ α νεω ςΡΠ ϖαριαντ τηε Μυλτιπλε Τριπ ςεηιχλε Ρουτινγ Προβλεm ωιτη Βαχκηαυλσ (ΜΤ−ςΡΠΒ) ισ ινϖεστιγατεδ. Τηε χλασσιχαλ ΜΤ−ςΡΠ mοδελ ισ εξτενδεδ βψ ινχλυδινγ τηε βαχκηαυλινγ ασπεχτ. Αν ΙΛΠ φορmυλατιον οφ τηε ΜΤ−ςΡΠΒ ισ φιρστ πρεσεντεδ ανδ ΧΠΛΕΞ ρεσυλτσ φορ σmαλλ ανδ mεδιυm σιζε ινστανχεσ αρε ρεπορτεδ. Φορ λαργε ινστανχεσ οφ τηε ΜΤ−ςΡΠΒ α Τωο−Λεϖελ ςΝΣ αλγοριτηm ισ δεϖελοπεδ. Το γαιν α χοντινυουσ βαλανχεδ ιντενσιφιχατιον ανδ διϖερσιφιχατιον δυρινγ τηε σεαρχη προχεσσ ςΝΣ ισ εmβεδδεδ ωιτη τηε σεθυεντιαλ ςΝD ανδ α mυλτι−λαψερ λοχαλ σεαρχη αππροαχη. Τηε αλγοριτηm ισ τεστεδ ον α σετ οφ νεω ΜΤ−ςΡΠΒ δατα ινστανχεσ ωηιχη ωε γενερατεδ. Ιντερεστινγ χοmπυτατιοναλ ρεσυλτσ αρε πρεσεντεδ. Τηε Τωο− Λεϖελ ςΝΣ προδυχεδ εξχελλεντ ρεσυλτσ ωηεν τεστεδ ον τηε σπεχιαλ ϖαριαντ οφ τηε ςΡΠΒ.

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The mixed vehicle routing problem with backhauls is investigated using ant system heuristic. This distribution problem seems to suffer from a lack of published work even though it has immense practical applicability especially within logistic systems. Some enhancements to the basic ant system algorithm are embedded into the search. In particular a focus is on the choice in the placement of ants, the use of site-dependent candidate list, the introduction of a look ahead-based visibility, and appropriate strategies for updating local and global trails. Encouraging computational results are reported when tested on benchmark data sets.

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Background The use of lithium during breast‐feeding has not been comprehensively investigated in humans due to concerns about lithium toxicity. Procedure We analyzed lithium in the kidneys of nursed pups of lithium medicated mothers, using analytical spectroscopy in a novel rat model. The mothers were healthy rats administered lithium via gavage (1000 mg/day Li2CO3 per 50 kg body weight). Results Lithium was detected in the breast milk, and in the blood of pups (0.08 mM), of lithium‐exposed dams at post‐natal day 18 (P18), during breast‐feeding. No lithium was detected after breast‐feeding, at P25 (4 days after cessation of nursing). The lithium pups blood had elevated urea nitrogen at P18 and reduced total T4 at P18 and P25, indicating a longer‐term effect on the kidneys and the thyroid gland. Multivariate machine‐learning analysis of spectroscopy data collected from the excised kidneys of pups showed elevated potassium in lithium‐exposed animals both during‐ and after breast‐feeding. The elevated renal potassium was associated with low nephrin expression in the kidneys measured immunohistochemically during breast‐feeding. After lithium exposure is stopped, the filtration of lithium from the kidneys reverses these effects. Our study showed that breastfeeding during lithium use has an effect on the kidneys of the offspring in rats.