Inventory Model with Seasonal Demand: A Specific Application to Haute Couture

In the stochastic multiperiod inventory problem, a vast majority of the literature deals with demand volume uncertainty. Other dimensions of uncertainty have generally been overlooked. In this paper, we develop a newsboy formulation for the aggregate multiperiod inventory problem intended for products of short sales season and without replenishments. A distinguishing characteristic of our formulation is that it takes a time dimension of demand uncertainty into account. The proposed model is particularly suitable for applications in haute couture, i.e., high fashion industry. The model determines the time of switching primary sales effort from one season to the next as well as optimal order quantity for each season with the objective of maximizing expected profit over the planning horizon. We also derive the optimality conditions for the time of switching primary sales effort and order quantity. Furthermore, we show that if time uncertainty and volume uncertainty are independent, order quantity becomes the main decision over the interval of the primary selling season. Finally, we demonstrate that the results from the two-season case can be directly extended to the multi-season case and the limited resource multiple-item case

Price competition with OEM-remanufactured products

Abstract Despite environmental and economic advantages of remanufacturing, the potential for cannibalizing the sales of new product by OEM-remanufactured products is a key obstacle for OEMs to remanufacture their end-of-life products. In this paper, we investigate the OEM-remanufacturing strategy and its impacts on price decisions by adopting a game-theoretic framework, where there is competition between a remanufacturer who sells third-party remanufactured products and an OEM who offers new products and chooses whether to introduce OEM-remanufactured products. We formulate consumer valuation for the products in the consideration of consumers' perceived similarity between the new and OEM-remanufactured products and, moreover, characterize the chain members' equilibrium pricing behavior concerning the availability of used products for remanufacturing. We elaborate the impacts of the entry of the OEM-remanufactured products on equilibrium results and show that the provision of OEM-remanufactured products is not necessarily harmful to the remanufacturer especially when consumers perceive the less similarity between the OEM's products. Results of this study intend to provide managerial insights for managers response to the changes in competitive dynamics, consumer characteristics, and cost factors

Primary Urothelial Carcinoma of the Ureter: 11-Year Experience in Taipei Veterans General Hospital

BackgroundUrothelial carcinoma of the upper urinary tract is relatively rare, occurring in 5% of all urothelial tumors. Ureteral urothelial carcinoma is even less common than that of the renal pelvis, accounting for about 25% of all upper urinary tract tumors. The aim of this study was to evaluate the clinical behavior, survival, recurrence and prognostic information of primary ureteral urothelial carcinoma from our 11 years of experience at the Taipei Veterans General Hospital.MethodsWe retrospectively reviewed 111 patients with ureteral urothelial carcinoma who had been treated in our hospital between January 1993 and December 2003. Tumor staging was according to the 2002 AJCC TNM classification and stage groupings. Patients with stage 0a and stage 0is were categorized as stage 0a/is, and patients with pathologic T stage pTa and pTis were categorized as pTa/is for statistical analysis. The Kaplan-Meier method was used for survival analysis.ResultsThere were 69 males and 42 females, with a mean age of 70.5 ± 9.4 years at diagnosis. Of the 111 patients, 5 presented with stage 0a/is, 38 with stage I, 23 with stage II, 21 with stage III, and 24 with stage IV. Nephroureterectomy with bladder cuff excision was performed in 78 patients, 12 patients received segmental resection of the ureter, 4 received ureteroscopic laser coagulation, and 17 underwent chemotherapy or radiotherapy or both. Tumors were located on the left side in 53 patients, on the right in 53, and bilaterally in 5. The most frequent initial presenting symptom was gross hematuria (65%). The mean postoperative follow-up period was 49.3 months. Disease recurrence in the nephroureterectomy group occurred in 36 patients (46.2%), with 17 (21.8%) at the urinary bladder, 2 (2.6%) at the retroperitoneum, 1 (1.3%) at the contralateral ureter, 6 (7.7%) with distant metastases to the lung, bone, distant lymph nodes or liver, and 10 (12.8%) at multiple sites. The 5-year cancer-specific survival rate was 100% for pTa/is, 95.2% for pT1, 69.4% for pT2, and 43.8% for pT3. All 3 pT4 cases died of cancer in a median of 12 months. Significant prognostic factors for cancer-specific survival by univariate analysis were pT (p = 0.00001), stage (p = 0.00001), type of treatment (p = 0.00001) and grade (p = 0.0001). On multivariate analysis, only stage (p = 0.0001) and grade (p = 0.014) were significant for cancer-specific and overall survival. Stage (p = 0.0001), pT (p =0.0001) and grade (p = 0.026) were also significant prognostic factors of recurrence in multivariate analysis.ConclusionOur experience showed that patients with pTa/is and pT1 tumors treated with radical surgery have excellent prognoses. Tumor stage and grade are the only significant prognostic factors for both cancer-specific and overall survival

Validation of a Chinese version of disease specific quality of life scale (HFS-36) for hemifacial spasm in Taiwan

<p>Abstract</p> <p>Background and object</p> <p>There was no Chinese questionnaire to evaluate the health-related quality of life (HRQoL) in patients with hemifacial spasm (HFS). In this study, we aimed to validate a new disease-specific HRQoL scale for HFS (HFS-36) in Chinese version, and compared it to SF-36, a generic HRQoL scale.</p> <p>Patients and Methods</p> <p>The HFS-36 Chinese version was modified from English version of HFS-30, including subscales of mobility, activities of daily living (ADL), emotional well-being, stigma, social support, cognition, bodily discomfort, and communication. All the items were scored on the 5-point scales, ranging from 0(never) to 4(always). Patients with HFS were asked to answer HFS-36 and SF-36 questionnaires on the same day before and 6-8 weeks after Botulinum toxin (BTX) injections, respectively. The reliability and validity of HFS-36 scale were evaluated statistically.</p> <p>Results</p> <p>Totally, 103 patients (68 females; 35 males) were recruited in this study, with a mean age of 57.6 ± 11.5 years and a mean duration of HFS for 7.6 ± 5.8 years. The intra-class correlation (ICC) and Cronbach's α were over 0.7 in the majority of items. HFS-36 showed a good correlation to HFS severity before BTX treatment and a significant improvement of subscale scoring after BTX treatment. HFS-36 also had a significant correlation to the mental health of SF-36.</p> <p>Conclusions</p> <p>The Chinese version of HFS-36 demonstrated a good reliability and validity in subscales of motility, ADL, emotion well-being, stigma and bodily discomfort. The HRQoL was significantly improved after BTX treatment assessed by HFS-36 or SF-36. Compared to SF-36, HFS-36 scale was more sensitive and specific to evaluate the HRQoL in HFS.</p

Clinical meaning of age-related expression of fecal cytokeratin 19 in colorectal malignancy

<p>Abstract</p> <p>Background</p> <p>Colorectal cancer (CRC) is one of the leading causes of malignant death worldwide. Because young age of onset is often considered a poor prognostic factor for CRC, it is important to identify the poor outcomes of CRC in a younger population and to consider an aggressive approach by implementing early treatment. Our aim was to specifically quantify the fecal cytokeratin 19 (CK19) transcript from CRC patients and investigate its correlation with clinical stage, tumor malignancy, and age.</p> <p>Methods</p> <p>The quantitation of fecal CK19 transcript was determined by a quantitative real-time reverse transcription polymerase chain in 129 CRC patients (45 younger than 60 years at diagnosis) and 85 healthy controls. The levels of CK19 protein were examined both in colonic cell lines and tissues.</p> <p>Results</p> <p>The analysis of 45 younger CRC patients (age ≤ 60 years) revealed that patients at the M1 stage had significantly higher expression levels of fecal CK19 mRNA when compared with healthy controls (<it>p </it>< 0.001) and patients at the M0 stage (<it>p </it>= 0.004). Additionally, the degree of consistency between the mean level of fecal CK19 mRNA and the distant metastatic rate in each age interval was up to 89% (<it>p </it>= 0.042).</p> <p>Conclusion</p> <p>These results indicate that high levels of fecal CK19 mRNA represent a potential marker for colorectal malignancy and for aggressive treatment of younger CRC patients.</p

Functional roles of arginine residues in mung bean vacuolar H+-pyrophosphatase

AbstractPlant vacuolar H+-translocating inorganic pyrophosphatase (V-PPase EC 3.6.1.1) utilizes inorganic pyrophosphate (PPi) as an energy source to generate a H+ gradient potential for the secondary transport of ions and metabolites across the vacuole membrane. In this study, functional roles of arginine residues in mung bean V-PPase were determined by site-directed mutagenesis. Alignment of amino-acid sequence of K+-dependent V-PPases from several organisms showed that 11 of all 15 arginine residues were highly conserved. Arginine residues were individually substituted by alanine residues to produce R→A-substituted V-PPases, which were then heterologously expressed in yeast. The characteristics of mutant variants were subsequently scrutinized. As a result, most R→A-substituted V-PPases exhibited similar enzymatic activities to the wild-type with exception that R242A, R523A, and R609A mutants markedly lost their abilities of PPi hydrolysis and associated H+-translocation. Moreover, mutation on these three arginines altered the optimal pH and significantly reduced K+-stimulation for enzymatic activities, implying a conformational change or a modification in enzymatic reaction upon substitution. In particular, R242A performed striking resistance to specific arginine-modifiers, 2,3-butanedione and phenylglyoxal, revealing that Arg242 is most likely the primary target residue for these two reagents. The mutation at Arg242 also removed F− inhibition that is presumably derived from the interfering in the formation of substrate complex Mg2+–PPi. Our results suggest accordingly that active pocket of V-PPase probably contains the essential Arg242 which is embedded in a more hydrophobic environment

Women with endometriosis have higher comorbidities: Analysis of domestic data in Taiwan

AbstractEndometriosis, defined by the presence of viable extrauterine endometrial glands and stroma, can grow or bleed cyclically, and possesses characteristics including a destructive, invasive, and metastatic nature. Since endometriosis may result in pelvic inflammation, adhesion, chronic pain, and infertility, and can progress to biologically malignant tumors, it is a long-term major health issue in women of reproductive age. In this review, we analyze the Taiwan domestic research addressing associations between endometriosis and other diseases. Concerning malignant tumors, we identified four studies on the links between endometriosis and ovarian cancer, one on breast cancer, two on endometrial cancer, one on colorectal cancer, and one on other malignancies, as well as one on associations between endometriosis and irritable bowel syndrome, one on links with migraine headache, three on links with pelvic inflammatory diseases, four on links with infertility, four on links with obesity, four on links with chronic liver disease, four on links with rheumatoid arthritis, four on links with chronic renal disease, five on links with diabetes mellitus, and five on links with cardiovascular diseases (hypertension, hyperlipidemia, etc.). The data available to date support that women with endometriosis might be at risk of some chronic illnesses and certain malignancies, although we consider the evidence for some comorbidities to be of low quality, for example, the association between colon cancer and adenomyosis/endometriosis. We still believe that the risk of comorbidity might be higher in women with endometriosis than that we supposed before. More research is needed to determine whether women with endometriosis are really at risk of these comorbidities

Identification of Gene Networks and Pathways Associated with Guillain-Barré Syndrome

BACKGROUND: The underlying change of gene network expression of Guillain-Barré syndrome (GBS) remains elusive. We sought to identify GBS-associated gene networks and signaling pathways by analyzing the transcriptional profile of leukocytes in the patients with GBS. METHODS AND FINDINGS: Quantitative global gene expression microarray analysis of peripheral blood leukocytes was performed on 7 patients with GBS and 7 healthy controls. Gene expression profiles were compared between patients and controls after standardization. The set of genes that significantly correlated with GBS was further analyzed by Ingenuity Pathways Analyses. 256 genes and 18 gene networks were significantly associated with GBS (fold change ≥2, P<0.05). FOS, PTGS2, HMGB2 and MMP9 are the top four of 246 significantly up-regulated genes. The most significant disease and altered biological function genes associated with GBS were those involved in inflammatory response, infectious disease, and respiratory disease. Cell death, cellular development and cellular movement were the top significant molecular and cellular functions involved in GBS. Hematological system development and function, immune cell trafficking and organismal survival were the most significant GBS-associated function in physiological development and system category. Several hub genes, such as MMP9, PTGS2 and CREB1 were identified in the associated gene networks. Canonical pathway analysis showed that GnRH, corticotrophin-releasing hormone and ERK/MAPK signaling were the most significant pathways in the up-regulated gene set in GBS. CONCLUSIONS: This study reveals the gene networks and canonical pathways associated with GBS. These data provide not only networks between the genes for understanding the pathogenic properties of GBS but also map significant pathways for the future development of novel therapeutic strategies