115 research outputs found

    Innovation Processes in the Car Industry: New Challenges for Management and Research

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    Over the past decades the development of a car has become a complex activity involving skills and resources from a variety of industries and actors, and requiring the accomplishment of tight regulatory norms and market needs. Technological and market forces have led incumbent firms to radically change the organization of their innovative activities, shifting from a closed vertically innovation model to a distributed one. The aim of this study is to review the main challenges carmakers are currently facing and the organizational and strategic solutions adopted to perform innovative and development activities within vertically fragmented networks. The chapter casts light on the organizational and strategic challenges of downstream development activities, then it also tries to overview the strategic role of up-front research activities, namely the research activities leading to patenting. The main changes brought by the distributed innovation model on new product development activities are discussed, focusing on the principles guiding outsourcing decisions and the governance mechanisms carmakers use to manage networks of external suppliers. The study, then, reviews the role of patenting in the industry as a means for carmakers to appropriate value from innovation in vertically fragmented networks. Finally, it discusses the changes on the organization of innovation activities that the emergence of the electric car-standard may imply for carmakers’ innovation strategy

    Green catalysts preparation using supercritical CO2 as an antisolvent

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    Using rapid supercritical CO2 antisolvent precipitation, a set of nanoscaled oxide catalyst precursors have been prepared, which were further calcined to give metal oxides, such as CuMnOx(hopcalite), CeC>2, Ti02 and ZnO etc. CuMnOx(hopcalite) was used as catalyst without further modification and other single metal oxides were used as supports for gold catalysts. These materials have been characterized using a full range of techniques: XRD, Raman, FT-IR, BET surface area, SEM, DTA/TGA and XPS. Element distribution in the as-precipitated materials was evaluated by TEM-EDX. The catalytic activity of our products was evaluated by low temperature (0 25 C) CO oxidation. For CuMnOx (hopcalites), an amorphous homogenous precursor mainly composed of acetates has been prepared. Following calcinations, separated copper nanocrystals supported on manganese oxide (Cu/MnOx) has been obtained. The preliminary catalytic data show the intrinsic activity for CO oxidation of the catalyst derived from this precursor is considerably higher than the conventional CuMn204 catalysts prepared by coprecipitation, and also currently available commercial catalysts. The results clearly show that a catalyst with enhanced activity can be prepared without the presence of intimately mixed copper and manganese oxide components. In addition, using mixed solvents, such as water-ethanol and water-DMF, crystalline heterogeneous precursors have been produced. With the addition of more water to the precursor solution, there appears to be a reaction between the metal acetates CO2, and H2O. Therefore, carbonates of the metals are precipitated instead of the acetate composition. Following calcination, less crystalline or even amorphous phase-separated nanostructure final catalysts retain the high surface area, which leads higher catalytic activities than that of the current commercial hopcalite catalysts. Furthermore, using 30% H2O2 as an oxidizer and ethanol as solvent, catalysts have been prepared as well. All the as-prepared catalysts exhibit higher catalytic activities on CO oxidation when compared to those from solvents in the absence of H2O2. Novel nano-polycrystalline Ce02 was produced. When it was used as a support for gold and gold palladium nanoparticles, the catalytic data show that the activity and catalyst lifetime for CO oxidation of a gold catalyst supported on this material is much greater than that for gold supported on regular Ce02 derived from the direct calcination of cerium acetylacetonate. In addition, the Au-Pd catalysts supported on Ce02 prepared using supercritical antisolvent precipitation are amongst the most active catalysts yet reported for the selective oxidation of alcohols and the direct oxidation of hydrogen to hydrogen peroxide. Similarly, T1O2 has been produced by supercritical process. When using it as a support for gold nanoparticles, the activity and stability for CO oxidation of a gold catalyst supported on this material is much greater than that for gold supported on regular Ti02 derived from the direct calcination of titanium oxide acetylacetonate. Finally, ZnO was prepared using supercritical process and then was used as supports for gold particles as well. The catalytic data show that it can give very high activity for CO oxidation.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    A Validated Risk Prediction Model for Breast Cancer in US Black Women

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    PURPOSE Breast cancer risk prediction models are used to identify high-risk women for early detection, targeted interventions, and enrollment into prevention trials. We sought to develop and evaluate a risk prediction model for breast cancer in US Black women, suitable for use in primary care settings. METHODS Breast cancer relative risks and attributable risks were estimated using data from Black women in three US population-based case-control studies (3,468 breast cancer cases; 3,578 controls age 30-69 years) and combined with SEER age- and race-specific incidence rates, with incorporation of competing mortality, to develop an absolute risk model. The model was validated in prospective data among 51,798 participants of the Black Women’s Health Study, including 1,515 who developed invasive breast cancer. A second risk prediction model was developed on the basis of estrogen receptor (ER)–specific relative risks and attributable risks. Model performance was assessed by calibration (expected/observed cases) and discriminatory accuracy (C-statistic). RESULTS The expected/observed ratio was 1.01 (95% CI, 0.95 to 1.07). Age-adjusted C-statistics were 0.58 (95% CI, 0.56 to 0.59) overall and 0.63 (95% CI, 0.58 to 0.68) among women younger than 40 years. These measures were almost identical in the model based on estrogen receptor–specific relative risks and attributable risks. CONCLUSION Discriminatory accuracy of the new model was similar to that of the most frequently used questionnaire-based breast cancer risk prediction models in White women, suggesting that effective risk stratification for Black women is now possible. This model may be especially valuable for risk stratification of young Black women, who are below the ages at which breast cancer screening is typically begun

    Dietary Vitamin A and Breast Cancer Risk in Black Women: The African American Breast Cancer Epidemiology and Risk (AMBER) Consortium

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    Background: Studies in women of European descent showed an inverse association of dietary vitamin A (retinol and carotenoids) intake with breast cancer risks, mainly in premenopausal women. Objectives: We examined whether higher compared with lower levels of dietary vitamin A are associated with reduced breast cancer risks among Black women by estrogen receptor (ER) and menopausal statuses. Methods: In this pooled analysis, data were from 3564 breast cancer cases and 11,843 controls (mean ages = 56.4 and 56.3 years, respectively) in the African American Breast Cancer Epidemiology and Risk (AMBER) Consortium. Dietary intake was assessed by FFQs. Multivariable logistic regressions were performed to estimate ORs and 95% CIs for study-specific quintiles of total vitamin A equivalents and individual carotenoids, and a pooled OR was estimated by a random-effect model. Results: We observed an inverse association of total vitamin A equivalents with ER-positive breast cancer (quintiles 5 compared with 1: pooled OR: 0.82; 95% CI: 0.67-1.00; P-trend = 0.045). The association was seen among premenopausal women (pooled OR: 0.60; 95% CI: 0.43-0.83; P-trend = 0.004), but not among postmenopausal women (pooled OR: 0.99; 95% CI: 0.77-1.28; P-trend = 0.78). Additionally, there were inverse associations of dietary β-carotene (quintiles 5 compared with 1: pooled OR: 0.70; 95% CI: 0.51-0.95; P-trend = 0.08) and lutein (pooled OR: 0.63; 95% CI: 0.45-0.87; P-trend = 0.020) with ER-positive breast cancer among premenopausal women. There was no evidence for an association of total vitamin A equivalents or individual carotenoids with ER-negative breast cancer, regardless of menopausal status. Conclusions: Our findings on dietary vitamin A and breast cancer risks in Black women are consistent with observations in women of European descent and advance the literature showing an inverse association for ER-positive disease

    Ki-67 Expression in Breast Cancer Tissue Microarrays

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    Objectives Ki-67 has been proposed to be used as a surrogate marker to differentiate luminal breast carcinomas (BCs). The purpose of this study was to determine the utility of and best approaches for using tissue microarrays (TMAs) and Ki-67 staining to distinguish luminal subtypes in large epidemiology studies of luminal/human epidermal growth factor receptor 2 (HER2)-negative BC. Methods Full-section and TMA (three 0.6-mm cores and two 1.0-mm cores) slides of 109 cases were stained with Ki-67 antibody. We assessed two ways of collapsing TMA cores: a weighted approach and mitotically active approach. Results For cases with at least a single 0.6-mm TMA core (n = 107), 16% were misclassified using a mitotically active approach and 11% using a weighted approach. For cases with at least a single 1.0-mm TMA core (n = 101), 5% were misclassified using either approach. For the 0.6-mm core group, there were 33.3% discordant cases. The number of discordant cases increased from 18% in the group of two cores to 40% in the group of three cores (P =.039). Conclusions Ki-67 tumor heterogeneity was common in luminal/HER2- BC. Using a weighted approach was better than using a mitotically active approach for core to case collapsing. At least a single 1.0-mm core or three 0.6-mm cores are required when designing a study using TMA

    Cross-ancestry GWAS meta-analysis identifies six breast cancer loci in African and European ancestry women

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    Our study describes breast cancer risk loci using a cross-ancestry GWAS approach. We first identify variants that are associated with breast cancer at P \u3c 0.05 from African ancestry GWAS meta-analysis (9241 cases and 10193 controls), then meta-analyze with European ancestry GWAS data (122977 cases and 105974 controls) from the Breast Cancer Association Consortium. The approach identifies four loci for overall breast cancer risk [1p13.3, 5q31.1, 15q24 (two independent signals), and 15q26.3] and two loci for estrogen receptor-negative disease (1q41 and 7q11.23) at genome-wide significance. Four of the index single nucleotide polymorphisms (SNPs) lie within introns of genes (KCNK2, C5orf56, SCAMP2, and SIN3A) and the other index SNPs are located close to GSTM4, AMPD2, CASTOR2, and RP11-168G16.2. Here we present risk loci with consistent direction of associations in African and European descendants. The study suggests that replication across multiple ancestry populations can help improve the understanding of breast cancer genetics and identify causal variants

    Variants in the vitamin D pathway, serum levels of vitamin D, and estrogen receptor negative breast cancer among African-American women: A case-control study

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    Introduction: American women of African ancestry (AA) are more likely than European Americans (EA) to have estrogen receptor (ER)-negative breast cancer. 25-hydroxyvitamin D (25OHD) is low in AAs, and was associated with ER-negative tumors in EAs. We hypothesized that racial differences in 25OHD levels, as well as in inherited genetic variations, may contribute, in part, to the differences in tumor characteristics.Methods: In a case (n = 928)-control (n = 843) study of breast cancer in AA and EA women, we measured serum 25OHD levels in controls and tested associations between risk and tag single nucleotide polymorphisms (SNPs) in VDR, CYP24A1 and CYP27B1, particularly by ER status.Results: More AAs had severe vitamin D deficiency ( twofold increased risk of ER-negative breast cancer among AAs (OR = 2.62, 95% CI = 1.38-4.98), but had no effect in EAs. rs2209314 decreased risk among EAs (OR = 0.38, 95% CI = 0.20-0.73), with no associations in AAs. The increased risk of ER-negative breast cancer in AAs compared to EAs was reduced and became non-significant (OR = 1.20, 95% CI = 0.80-1.79) after adjusting for these two CYP24A1 SNPs.Conclusions: These data suggest that genetic variants in the vitamin D pathway may be related to the higher prevalence of ER-negative breast cancer in AA women. © 2012 Yao et al.; licensee BioMed Central Ltd
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