372 research outputs found

    Gangs, displaced, and group-based aggression

    Get PDF
    Many urban areas experienced an alarming growth of gang activity and violence during the end of the 20th and the beginning of the 21st centuries. Gang members, motivated by various factors, commit a variety of different types of violent acts towards rivals and other targets. Our focus involves instances of displaced aggression, which generally refers to situations in which aggression is targeted towards individuals who have either not themselves committed an offense against the aggressor (s), or who provide an offense that is too mild to justify the aggression levels that are expressed towards them. We discuss how social–psychological mechanisms and models of two types of displaced aggression might help explain some aspects of the retaliatory behavior that is expressed by members of street gangs. We also propose general techniques that have the potential to reduce such aggressive behavior

    The continuous recombination of codification and personalisation km strategies: A retrospective study

    Get PDF
    It is increasingly considered important to understand how companies plan their Knowledge Management (KM) strategy. The literature provides evidence that there may be different possible approaches to KM strategy. A significant distinction has been made between "codification" and "personalization". Sometimes, these two approaches have been seen to be alternative to one another. In other cases scholars argued that a company can follow a strategy that mixes the two approaches depending on diverse intertwined factors. Still, on this topic, the literature provides various and sometimes contrasting results that need clarification and confirmation. Especially, there is the need to understand if changes in internal and external conditions may induce modifications in a firm's KM strategy.The goal of the study is to analyse how the mix of codification and personalisation can vary over time in the same company, due to changing organizational and environmental conditions. With this purpose, the evolution of KM initiatives of a multinational company was investigated. The findings of the study confirm that the strategic mix can change over the years due to modifications in the factors of the company's internal and external context. Furthermore, the case shows that the different factors have different weight and play a different role in influencing such changes. Specifically, in the investigated case, the factors related to the competitive context affected the evolution of the KM strategy more significantly than internal factors (which were just enablers or constraints of the evolutionary path). In addition, the study shows that this classic distinction between codification and personalization may not be easy to use in practical terms, due to the complexity of KM activities and needs in a company: This point can represent a fresh start of a future research agenda

    Production of human recombinant proapolipoprotein A-I in Escherichia coli: purification and biochemical characterization

    Get PDF
    A human liver cDNA library was used to isolate a clone coding for apolipoprotein A-I (Apo A-I). The clone carries the sequence for the prepeptide (18 amino acids), the propeptide (6 amino acids), and the mature protein (243 amino acids). A coding cassette for the proapo A-I molecule was reconstructed by fusing synthetic sequences, chosen to optimize expression and specifying the amino-terminal methionine and amino acids -6 to +14, to a large fragment of the cDNA coding for amino acids 15-243. The module was expressed in pOTS-Nco, an Escherichia coli expression vector carrying the regulatable X P^ promoter, leading to the production of proapolipoprotein A-I at up to 10% of total soluble proteins. The recombinant polypeptide was purified and characterized in terms of apparent molecular mass, isoelectric point, and by both chemical and enzymatic peptide mapping. In addition, it was assayed in vitro for the stimulation of the enzyme lecithin: cholesterol acyltransferase. The data show for the first time that proapo A-I can be produced efficiently in E. coli as a stable and undegraded protein having physical and functional properties indistinguishable from those of the natural product

    Genetic and nongenetic factors associated with milk color in dairy cows

    Get PDF
    peer-reviewedMilk color is one of the sensory properties that can influence consumer choice of one product over another and it influences the quality of processed dairy products. This study aims to quantify the cow-level genetic and nongenetic factors associated with bovine milk color traits. A total of 136,807 spectra from Irish commercial and research herds (with multiple breeds and crosses) were used. Milk lightness (Lˆ*) , red-green index (aˆ*) and yellow-blue index (bˆ*) were predicted for individual milk samples using only the mid-infrared spectrum of the milk sample. Factors associated with milk color were breed, stage of lactation, parity, milking-time, udder health status, pasture grazing, and seasonal calving. (Co)variance components for Lˆ*,aˆ* , and bˆ* were estimated using random regressions on the additive genetic and within-lactation permanent environmental effects. Greater bˆ* value (i.e., more yellow color) was evident in milk from Jersey cows. Milk Lˆ* increased consistently with stage of lactation, whereas aˆ* increased until mid lactation to subsequently plateau. Milk bˆ* deteriorated until 31 to 60 DIM, but then improved thereafter until the end of lactation. Relative to multiparous cows, milk yielded by primiparae was, on average, lighter (i.e., greater Lˆ* ), more red (i.e., greater aˆ* ), and less yellow (i.e., lower bˆ* ). Milk from the morning milk session had lower Lˆ*,aˆ*, and bˆ* Heritability estimates (±SE) for milk color varied between 0.15 ± 0.02 (30 DIM) and 0.46 ± 0.02 (210 DIM) for Lˆ* , between 0.09 ± 0.01 (30 DIM) and 0.15 ± 0.02 (305 DIM) for aˆ* , and between 0.18 ± 0.02 (21 DIM) and 0.56 ± 0.03 (305 DIM) for bˆ* For all the 3 milk color features, the within-trait genetic correlations approached unity as the time intervals compared shortened and were generally <0.40 between the peripheries of the lactation. Strong positive genetic correlations existed between bˆ* value and milk fat concentration, ranging from 0.82 ± 0.19 at 5 DIM to 0.96 ± 0.01 at 305 DIM and confirming the observed phenotypic correlation (0.64, SE = 0.01). Results of the present study suggest that breeding strategies for the enhancement of milk color traits could be implemented for dairy cattle populations. Such strategies, coupled with the knowledge of milk color traits variation due to nongenetic factors, may represent a tool for the dairy processors to reduce, if not eliminate, the use of artificial pigments during milk manufacturing

    Modification of Amorphous Mesoporous Zirconia Nanoparticles with Bisphosphonic Acids: A Straightforward Approach for Tailoring the Surface Properties of the Nanoparticles

    Get PDF
    The use of readily prepared bisphosphonic acids obtained in few steps through a thio-Michael addition of commercially available thiols on tetraethyl vinylidenebisphosphonate enables the straightforward surface modification of amorphous mesoporous zirconia nanoparticles. Simple stirring of the zirconia nanoparticles in a buffered aqueous solution of the proper bisphosphonic acid leads to the surface functionalization of the nanoparticles with different kinds of functional groups, charge and hydrophobic properties. Formation of both chemisorbed and physisorbed layers of the bisphosphonic acid take place, observing after extensive washing a grafting density of 1.1 molecules/nm2 with negligible release in neutral or acidic pH conditions, demonstrating stronger loading compared to monophosphonate derivatives. The modified nanoparticles were characterized by IR, XPS, ζ-potential analysis to investigate the loading of the bisphosphonic acid, FE-SEM to investigate the size and morphologies of the nanoparticles and 31P and 1H MAS NMR to investigate the coordination motif of the phosphonate units on the surface. All these analytical techniques demonstrated the strong affinity of the bisphosphonic moiety for the Zr(IV) metal centers. The functionalization with bisphosphonic acids represents a straightforward covalent approach for tailoring the superficial properties of zirconia nanoparticles, much straightforward compared the classic use of trisalkoxysilane or trichlorosilane reagents typically employed for the functionalization of silica and metal oxide nanoparticles. Extension of the use of bisphosphonates to other metal oxide nanoparticles is advisable

    Operation of Energy MicroGrids

    Get PDF
    Integrated Operation is a strategy to operate the Energy MicroGrid as an integrated system. In this strategy, a CHP plant, an electric water heater, and thermal storage were operated to support both electricity and heat networks of the Energy MicroGrid. An Integrated Optimal Power Flow was formulated and was used to investigate the advantages of this Integrated Operation. Simulations indicated that Integrated Operation minimised generation curtailment and load shedding. It also reduced electricity imported from the main grid and the operating cost.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
    corecore