Defective quality

Sirt1-deficiency causes defective protein quality control

Protein quality control is an important mechanism to maintain cellular homeostasis. Damaged proteins have to be restored or eliminated by degradation, which is mainly achieved by molecular chaperones and the ubiquitin-proteasome system. The NAD(+)-dependent deacetylase Sirt1 has been reported to play positive roles in the regulation of cellular homeostasis in response to various stresses. Howev...

Germline quality control: eEF2K stands guard to eliminate defective oocytes.

The control of germline quality is critical to reproductive success and survival of a species; however, the mechanisms underlying this process remain unknown. Here, we demonstrate that elongation factor 2 kinase (eEF2K), an evolutionarily conserved regulator of protein synthesis, functions to maintain germline quality and eliminate defective oocytes. We show that disruption of eEF2K in mice red...

Imperfect and defective outputs in production process

An Integrated Inventory Model with Controllable Lead time and Setup Cost Reduction for Defective and Non-Defective Items

In this paper, the study deals with the lead time and setup reduction problem in the vendor-purchaser integrated inventory model. The cost of capital (i.e., opportunity cost) is one of the key factors in making the inventory and investment decisions. Lead time is an important element in any inventory system. The proposed model is presents an integrated inventory model with controllable lead tim...

Optimal lot sizing in screening processes with returnable defective items

This paper is an extension of Hsu and Hsu (Int J Ind Eng Comput 3(5):939–948, 2012) aiming to determine the optimal order quantity of product batches that contain defective items with percentage nonconforming following a known probability density function. The orders are subject to 100 % screening process at a rate higher than the demand rate. Shortage is backordered, and defective items...