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Elshafei and Alfares have developed a dynamic programming (DP) algorithm for minimizing the total sequence-dependent cost in a constrained single-shift days-off scheduling problem. In general, however, their proposed DP algorithm may not obtain an optimal solution unlike their claim; in their highlighted security personnel scheduling example, we show how to improve their alleged optimal schedule just by inspection. The purpose of this paper is to describe better solution approaches to their challenging sequence-dependent workforce scheduling problem. We first explain why their DP algorithm encounters difficulties in finding an optimal solution with emphasis on the importance of proper state description for DP. We then describe how to correct their DP procedure with minimal effort. After that, we confirm such a better scheduling result by solving an associated mathematical programming problem with the Gurobi Optimizer, a widely recognized mathematical programming solver. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2010.07.021 Byline: Kazuo Yamagata, Jun Ueda, Eiji Mizutani, Mitinori Saitou, Teruhiko Wakayama Keywords: ES cell derivation; Live-cell imaging; Oct4; Apoptosis Abstract: Despite the broad literature on embryonic stem cells (ESCs), their derivation process remains enigmatic. This may be because of the lack of experimental systems that can monitor this prolonged cellular process. Here we applied a live-cell imaging technique to monitor the process of ESC derivation over 10days from morula to outgrowth phase using an Oct4/eGFP reporter system. Our imaging reflects the 'natural' state of ESC derivation, as the ESCs established after the imaging were both competent in chimeric mice formation and germ-line transmission. Using this technique, ESC derivation in conventional conditions was imaged. After the blastocoel was formed, the intensity of Oct4 signals attenuated in the trophoblast cells but was maintained in the inner cell mass (ICM). Thereafter, the Oct4-positive cells scattered and their number decreased along with apoptosis of the other Oct4-nagative cells likely corresponds to trophoblast and hypoblast cells, and then only the surviving Oct4-positive cells proliferated and formed the colony. All embryos without exception passed through this cell death phase. Importantly, the addition of caspase inhibitor Z-VAD-FMK to the medium dramatically suppressed the loss of Oct4-positive cells and also other embryo-derived cells, suggesting that the cell deaths was induced by a caspase-dependent apoptotic pathway. Next we imaged the ESC derivation in 3i medium, which consists of chemical compounds that can suppress differentiation. The most significant difference between the conventional and 3i methods was that there was no obvious cell death in 3i, so that the colony formation was rapid and all of the Oct4-positive cells contributed to the formation of the outgrown colony. These data indicate that the prevention of cell death in epiblast cells is one of the important events for the successful establishment of ESCs. Thus, our imaging technique can advance the understanding of the time-dependent cellular changes during ESC derivation. Article History: Received 6 February 2010; Revised 9 July 2010; Accepted 17 July 2010

Author(s): Masaki Yagi [1]; Satoshi Kishigami [2]; Akito Tanaka [1]; Katsunori Semi [1]; Eiji Mizutani [2, 3]; Sayaka Wakayama [2, 3]; Teruhiko Wakayama [2, 3]; Takuya Yamamoto (corresponding author) [1, [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2005.10.026 Byline: Satoshi Kishigami, Nguyen Van Thuan, Takafusa Hikichi, Hiroshi Ohta, Sayaka Wakayama, Eiji Mizutani, Teruhiko Wakayama Keywords: Mouse; DNA methylation; Microinsemination; Round spermatid injection; Zygote Abstract: Although round spermatid injection can be used to create progeny for males who do not produce mature sperm, the rate of successful embryogenesis after such procedures is significantly lower than that for similar procedures using mature spermatozoa. The mechanisms underlying this difference are unknown. In this study, we demonstrate that, unlike the normal paternal genome, the paternal zygotic genome derived from a round spermatid is highly remethylated before first mitosis after demethylation. Genomes from elongated spermatids exhibited an intermediate level of DNA methylation, between those of round spermatids and mature spermatozoa, suggesting that the male germ cell acquires the ability to maintain its undermethylated state in the paternal zygotic genome during this phase of spermiogenesis. In addition, treatment of zygotes with trichostatin A led to a significant reduction in DNA methylation, specifically in the spermatid-derived paternal genome, except for the pericentromeric regions enriched by trimethylation of Lys9 of histone H3. These data provide insight into epigenetic errors that may be associated with the poor development of embryos generated from immature spermatozoa. Author Affiliation: Laboratory for Genomic Reprogramming, Center for Developmental Biology, RIKEN Kobe, 2-2-3 Minatojima-minamimachi, Kobe 650-0047, Japan Article History: Received 1 June 2005; Revised 4 October 2005; Accepted 19 October 2005

This paper describes color reproduction and correction of images captured by electronic cameras under multiple illumination (or lighting) conditions, relating to color device characterization for enhancing the quality of color in the obtained images. In particular, we shall highlight a very practical use of neuro-fuzzy modular network coactive neuro-fuzzy inference systems (CANFIS) models for this application, and discuss their strengths and weaknesses compared with other adaptive network models [e.g., multilayer perceptron (MLP)] as well as conventional lookup-table-type (TRC-matrix) methods. Our in-depth investigation based on comprehensive numerical tests with a wide variety of illumination/lighting data (180 sources of illumination) shows that the 'neuro-fuzzy CANFIS with MLP local experts' possesses a remarkable generalization/approximation capacity, even under a very restricted condition where only four-illuminant data sets were permitted to use for optimization purpose because of efficient practical implementation subject to an industrial setting. Index Terms--Coactive neuro-fuzzy inference systems (CANFIS) neuro-fuzzy modular networks, color device characterization, color reproduction, cyan magenta yellow green/ref green blue (CMYG/RGB) electronic cameras, multilayer perceptrons (MLPs), multiple illuminations.

Cell transplantation with embryonic stem (ES) cell progeny requires immunological compatibility with host tissue. 'Therapeutic cloning' is a strategy to overcome this limitation by generating nuclear transfer (nt)ES cells that are genetically matched to an individual. Here we establish the feasibility of treating individual mice via therapeutic cloning. Derivation of 187 ntES cell lines from 24 parkinsonian mice, dopaminergic differentiation, and transplantation into individually matched host mice showed therapeutic efficacy and lack of immunological response., Previous work has shown generation of pluripotent mouse ntES cells via somatic cell nuclear transfer with adult fibroblasts or cumulus cells as nucleus donors (1,2). Such ntES cell lines have [...]