Supplier and retailer coordination under stochastic price-dependent demand and fast moving items

We consider a centralized supply chain system consisting of a one supplier and one retailer. The customers’ demand is a compound Poisson process with price-dependent intensity and continuous batch size distribution. The intensity of the customers’ arrivals is assumed to be sufficiently high to use a diffusion approximation of the demand process. We assume that the supplier has complete information about the rational retailer’s behavior in the framework of the newsvendor problem. The objective is to find a joint pricing and ordering policy so as to maximize the retailer’s expected profit and supplier’s profit. The equations for the optimal prices main parts are obtained and the example of the price-intensity dependence is considered

Estimating the demand parameters for single period problem, Markov-modulated Poisson demand, large lot size, and unobserved lost sales

We consider a single-period single-item problem when the demand is a Markov-modulated Poisson process with hidden states, unknown intensities and continuous batch size distribution. The number of customers and lot size are assumed to be large enough. The estimators of demand mean and standard deviation for unobservable lost sales in the steady state are considered. The procedures are based on two censored samples: observed selling durations and the demands over the period. Numerical results are given

Mapping-by-sequencing using NGS-based 3′-MACE-Seq reveals a new mutant allele of the essential nodulation gene Sym33 (IPD3) in pea (Pisum sativum L.)

Large collections of pea symbiotic mutants were accumulated in the 1990s, but the causal genes for a large portion of the mutations are still not identified due to the complexity of the task. We applied a Mapping-by-Sequencing approach including Bulk Segregant Analysis and Massive Analysis of cDNA Ends (MACE-Seq) sequencing technology for genetic mapping the Sym11 gene of pea which controls the formation of symbioses with both nodule bacteria and arbuscular-mycorrhizal fungi. For mapping we developed an F2-population from the cross between pea line N24 carrying the mutant allele of sym11 and the wild type NGB1238 (=JI0073) line. Sequencing libraries were prepared from bulks of 20 plants with mutant and 12 with wild-type phenotype. MACE-Seq differential gene expression analysis between mutant-phenotype and wild-type-phenotype bulks revealed 2,235 genes, of which 514 (23%) were up-regulated and 1,721 (77%) were down-regulated in plant roots inoculated with rhizobia as a consequence of sym11 mutation. MACE-Seq also detected single nucleotide variants between bulks in 217 pea genes. Using a novel mathematical model we calculated the recombination frequency (RF) between the Sym11 gene and these 217 polymorphic genes. Six genes with the lowest RF were converted into CAPS or dCAPS markers and genetically mapped on the complete mapping population of 108 F2-plants which confirmed their tight linkage to Sym11 and to each other. The Medicago truncatula Gaertn. (Mt) homologs of these genes are located in a distinct region of Mt chromosome 5, which corresponds to linkage group I of pea. Among 94 candidate genes from this region only one was down-regulated—the pea Sym33 homolog of the Mt IPD3 gene which is essential for nodulation. Sequencing of the Sym33 allele of the N24 (sym11) mutant revealed a single nucleotide deletion (c.C319del) in its third exon resulting in a codon shift in the open reading frame and premature translation termination. Thus, we identified a novel mutant allele sym33-4 most probably responsible for the mutant phenotype of the N24 (sym11) line, thereby demonstrating that mapping by MACE-Seq can be successfully used for genetic mapping of mutations and identification of candidate genes in pea

Molecular Genetic Analysis of 103 Sporadic Colorectal Tumours in Czech Patients

The Czech Republic has one of the highest incidences of colorectal cancer (CRC) in Europe. To evaluate whether sporadic CRCs in Czech patients have specific mutational profiles we analysed somatic genetic changes in known CRC genes (APC, KRAS, TP53, CTNNB1, MUTYH and BRAF, loss of heterozygosity (LOH) at the APC locus, microsatellite instability (MSI), and methylation of the MLH1 promoter) in 103 tumours from 102 individuals. The most frequently mutated gene was APC (68.9% of tumours), followed by KRAS (31.1%), TP53 (27.2%), BRAF (8.7%) and CTNNB1 (1.9%). Heterozygous germline MUTYH mutations in 2 patients were unlikely to contribute to the development of their CRCs. LOH at the APC locus was found in 34.3% of tumours, MSI in 24.3% and MLH1 methylation in 12.7%. Seven tumours (6.9%) were without any changes in the genes tested. The analysis yielded several findings possibly specific for the Czech cohort. Somatic APC mutations did not cluster in the mutation cluster region (MCR). Tumours with MSI but no MLH1 methylation showed earlier onset and more severe mutational profiles compared to MSI tumours with MLH1 methylation. TP53 mutations were predominantly located outside the hot spots, and transitions were underrepresented. Our analysis supports the observation that germline MUTYH mutations are rare in Czech individuals with sporadic CRCs. Our findings suggest the influence of specific ethnic genetic factors and/or lifestyle and dietary habits typical for the Czech population on the development of these cancers

Weight function optimization of dynamic pricing profit for perishable product: Considering leftovers and salvage value

We consider a single product under a finite time horizon and a non-homogeneous compound Poisson customers flow with a rate depending on the stock level and an unknown time-dependent weight function. The rate is controlled by a retail price. In the framework of the diffusion approximation of the stock level process and a linear representation of an intensity-of-price dependence. Considering the salvage value of product, we solve the task of the expected profit maximization with respect to the weight function and lot size. We propose a simple approximation of the optimal weight functio

Supplier and retailer coordination under stochastic price-dependent demand and fast moving items

We consider a centralized supply chain system consisting of a one supplier and one retailer. The customers’ demand is a compound Poisson process with price-dependent intensity and continuous batch size distribution. The intensity of the customers’ arrivals is assumed to be sufficiently high to use a diffusion approximation of the demand process. We assume that the supplier has complete information about the rational retailer’s behavior in the framework of the newsvendor problem. The objective is to find a joint pricing and ordering policy so as to maximize the retailer’s expected profit and supplier’s profit. The equations for the optimal prices main parts are obtained and the example of the price-intensity dependence is considered