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191.
In this paper we examine the role of top management in relation to the diversified operations of a company and the meaning of “strategic planning” for these entities. We briefly examine two general approaches to generation of growth: conglomeration (portfolio management) and synergistic growth. We argue that the second is preferable. We then challenge the universally popluar notion that growth is the appropriate objective for a business entity. We propose the concept of “development” as a better alternative. We offer the case of Armco's Latin American Division (known as ALAD) as an illustration of the kind of thinking that emerges when development is taken as the corporate objective. We present a five-phase strategy that combines the notions of synergistic growth and corporate development in a systemic framework.  相似文献   
192.
Summary We synthesized the m-maleimidobenzoyl derivative of digoxigenin-3-0-succinate (through a p-phenylenediamine bridge) as a hapten derivative directed towards coupling to sulfhydryl groups of -galactosidase. Prepared enzyme conjugate had about 97% of the enzyme labeled with the hapten derivative while retaining full enzyme activity. The enzyme immunoassay for digoxin we prepared showed a maximum sensitivity of 30 pg per assay (c.v.=3%) with minimal cross-reaction with digotoxin (3.8%). Our method for hapten conjugation to -galactosidase is highly efficient and is simple and easily replicated.  相似文献   
193.

Over the last decade, there has been an exponential growth of services over the Internet. Services such as online gaming are gaining popularity, whereas, Voice over Internet (VoIP) has been well established. Storage, management and processing of data have moved away from the devices to the cloud. Quality of experience (QoE) defined as the user’s perception of service quality is utilized in different technologies, services and products for improving end user satisfaction and provides quality of service (QoS) according to their demands. In this paper, we describe the utilization of QoE in different technologies, services and products for improving end user satisfaction. Specifically, we present the latest developments in QoE in multimedia services, network management, VoIP, web development, games and cloud computing. Finally, we discuss the current research, solutions and present open issues of future research in QoE.

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194.
The Mediterranean Sea is known as a biodiversity hot spot, with 16,848 species reported. Biodiversity is higher in coastal areas and decreases with depth. However, knowledge about the southwestern sector remains scarce. For the last three decades, sampling of soft-bottom communities along the 1180 km of the shallow Algerian coast (0–136 m) has recorded 1642 macrobenthic species. There is a decreasing west–east species-richness gradient, especially for the total species richness and the amphipods. In addition, quantitative sampling in Bou Ismail Bay in summer 1988 (98 sampling sites for a total of 841 species) shows that diversity indices (i.e. species richness, >100 species for 0.2 m?2; Shannon diversity, >6.0; and ES50, >34) are among the highest for similar sand and muddy-fine sand communities in the Mediterranean Sea and the northeastern Atlantic Ocean. Bou Ismail Bay appears to have the highest species richness among Algerian bays, probably because of its variety of benthic habitats and the absence of significant pollution in this area. Monitoring must be undertaken to survey this high biodiversity, and a national strategy should be proposed to preserve high diversity zones.  相似文献   
195.
Prostate cancer (PrCa) is the most frequently diagnosed male cancer in developed countries. We conducted a multi-stage genome-wide association study for PrCa and previously reported the results of the first two stages, which identified 16 PrCa susceptibility loci. We report here the results of stage 3, in which we evaluated 1,536 SNPs in 4,574 individuals with prostate cancer (cases) and 4,164 controls. We followed up ten new association signals through genotyping in 51,311 samples in 30 studies from the Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL) consortium. In addition to replicating previously reported loci, we identified seven new prostate cancer susceptibility loci on chromosomes 2p11, 3q23, 3q26, 5p12, 6p21, 12q13 and Xq12 (P = 4.0 × 10(-8) to P = 2.7 × 10(-24)). We also identified a SNP in TERT more strongly associated with PrCa than that previously reported. More than 40 PrCa susceptibility loci, explaining ~25% of the familial risk in this disease, have now been identified.  相似文献   
196.
Neuroblastoma is a childhood cancer that can be inherited, but the genetic aetiology is largely unknown. Here we show that germline mutations in the anaplastic lymphoma kinase (ALK) gene explain most hereditary neuroblastomas, and that activating mutations can also be somatically acquired. We first identified a significant linkage signal at chromosome bands 2p23-24 using a whole-genome scan in neuroblastoma pedigrees. Resequencing of regional candidate genes identified three separate germline missense mutations in the tyrosine kinase domain of ALK that segregated with the disease in eight separate families. Resequencing in 194 high-risk neuroblastoma samples showed somatically acquired mutations in the tyrosine kinase domain in 12.4% of samples. Nine of the ten mutations map to critical regions of the kinase domain and were predicted, with high probability, to be oncogenic drivers. Mutations resulted in constitutive phosphorylation, and targeted knockdown of ALK messenger RNA resulted in profound inhibition of growth in all cell lines harbouring mutant or amplified ALK, as well as in two out of six wild-type cell lines for ALK. Our results demonstrate that heritable mutations of ALK are the main cause of familial neuroblastoma, and that germline or acquired activation of this cell-surface kinase is a tractable therapeutic target for this lethal paediatric malignancy.  相似文献   
197.
198.
Data revisions and selections of appropriate forwarding‐looking variables have a major impact on true identification of news shocks and quality of research findings derived from structural vector autoregression (SVAR) estimation. This paper revisits news shocks to identify the role of different vintages of total factor productivity (TFP) series and term structure of interest rates as major prognosticators of future economic growth. There is a growing strand of literature regarding the use of utilization‐adjusted TFP series, provided by Fernald (Federal Reserve Bank of San Francisco, Working Paper Series, 2014) for identification of news shocks. We reestimate Barsky and Sims' (Journal of Monetary Economics, 2011, 58, 273–289) empirical analysis by employing 2007 and 2015 vintages of TFP data. We find substantial quantitative as well as qualitative differences among impulse response functions when using 2007 and 2015 vintages of TFP data. Output and hours initially decline, followed by quick reversal of both variables. In sharp contrast to results achieved by the 2007 vintage of TFP data, results achieved by the 2015 vintage of TFP data depict that output and hours will increase in response to positive TFP shock. By including term structure data in our VAR specification, total surprise technology shock and news shock account for 97% and 92% of the forecast error variance in total TFP and total output respectively. We find that revisions in TFP series over time ultimately impact the conclusion regarding news shocks on business cycles. Our results support the notion that term structure data help in better identification of news shock as compared to other forward‐looking variables.  相似文献   
199.
Aicardi-Goutières syndrome (AGS) is an autosomal recessive neurological disorder, the clinical and immunological features of which parallel those of congenital viral infection. Here we define the composition of the human ribonuclease H2 enzyme complex and show that AGS can result from mutations in the genes encoding any one of its three subunits. Our findings demonstrate a role for ribonuclease H in human neurological disease and suggest an unanticipated relationship between ribonuclease H2 and the antiviral immune response that warrants further investigation.  相似文献   
200.
Cell transplantation is a potential strategy for treating blindness caused by the loss of photoreceptors. Although transplanted rod-precursor cells are able to migrate into the adult retina and differentiate to acquire the specialized morphological features of mature photoreceptor cells, the fundamental question remains whether transplantation of photoreceptor cells can actually improve vision. Here we provide evidence of functional rod-mediated vision after photoreceptor transplantation in adult Gnat1?/? mice, which lack rod function and are a model of congenital stationary night blindness. We show that transplanted rod precursors form classic triad synaptic connections with second-order bipolar and horizontal cells in the recipient retina. The newly integrated photoreceptor cells are light-responsive with dim-flash kinetics similar to adult wild-type photoreceptors. By using intrinsic imaging under scotopic conditions we demonstrate that visual signals generated by transplanted rods are projected to higher visual areas, including V1. Moreover, these cells are capable of driving optokinetic head tracking and visually guided behaviour in the Gnat1?/? mouse under scotopic conditions. Together, these results demonstrate the feasibility of photoreceptor transplantation as a therapeutic strategy for restoring vision after retinal degeneration.  相似文献   
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