introduction: lymphoscintigraphy is imaging of the lymphatic system and has been integrated into the sentinel node mapping procedures. lymphoscintigraphy usually encompasses early or delayed static images. however, immediate dynamic imaging of the lymphatic basins and tumors has also been used as an adjunct lymphoscintigraphy imaging. the aim of this study was to assess the role of early dynami...

HYPOTHESIS The required sample size of a prospective randomized trial comparing standard pancreaticoduodenectomy with pancreaticoduodenectomy plus extended lymphadenectomy for pancreatic adenocarcinoma is prohibitively large, making such a trial infeasible. DESIGN Retrospective cohort study. SETTING Comprehensive cancer center. PATIENTS We identified 158 patients who underwent pancreatico...

Introduction: Lymphoscintigraphy is imaging of the lymphatic system and has been integrated into the sentinel node mapping procedures. Lymphoscintigraphy usually encompasses early or delayed static images. However, immediate dynamic imaging of the lymphatic basins and tumors has also been used as an adjunct lymphoscintigraphy imaging. The aim of this study was ...

BACKGROUND The need for routine axillary lymph node dissection (ALND) in patients with invasive breast cancer and low-volume sentinel node (SN) involvement is questionable. Accurate prediction of second echelon lymph node involvement could identify those patients most likely to benefit from ALND. METHODS A consecutive series of 317 patients with invasive breast cancer and a tumor positive axi...

In multi-echelon inventory systems the performance of a given node is affected by events that occur at many other nodes and in many other time periods. For example, a supply disruption upstream will have an effect on downstream, customer-facing nodes several periods later as the disruption "cascades" through the system. There is very little research on stock-out prediction in single-echelon sys...

In allusion to such problems as low accuracy and long convergence time in traditional two-echelon vehicle routing optimization algorithm, a Memetic algorithm (QDEMA) based on Q learning theory and differential evolution is proposed in this article to solve above problems. Firstly, it is necessary to research the two-echelon vehicle routing optimization problem and adopt the optimal segmentation...

This research introduces a new variant of the two-echelon vehicle routing problem (2EVRP) called with transshipment nodes and occasional drivers (2EVRP-TN-OD). In addition to city freighters in second-echelon network, set (ODs) is available serve customers. ODs are basis crowd-shipping system which crowds planned trips willing take detours deliver packages exchange for some compensation. To cus...

We consider a two-echelon single commodity inventory system with one warehouse(supplier) at the higher echelon and one retailer at the lower echelon. The retailer stocks individual items of a commodity and satisfies unit demands which occur according to a Poisson process. The supplier stocks these items in packets and uses these packetsto: (i) satisfy the demands that occur for single packet an...

Firms with omni-channel multi-echelon distribution networks (OMDC) integrate all of their sale channels and echelons to achieve an effective matching multi-type orders a shared inventory. However, the high operational cost caused by insufficient use inventory resources unreasonable order allocation restricts sustainable development firms. To this end, joint decisions optimization (IO) (OA) are ...

• Two-echelon vehicle routing problem with three important real-world extensions. Simultaneous handling of reverse flows, satellite capacities, and timing aspects. Matheuristic solution approach combines different decomposition strategies. New for efficient feasibility testing local-search moves. Last-mile collection delivery services often rely on multi-echelon logistic systems many types prac...