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Strength of weakness
(2020)
The paper investigates quality management in teaching and learning in higher education institutions from a principal-agent perspective. Based on data gained from semi-structured interviews and from a nation-wide survey with quality managers of German higher education institutions, the study shows how quality managers position themselves in relation to their perception of the interests of other actors in higher education institutions. The paper describes the various interests and discusses the main implications of this constellation of actors. It argues that quality managers, although they may be considered as rather weak actors within the higher education institution, may be characterised as having a strength of weakness due to diverging interests of their principals.
Alcohol use disorder (AUD) is the most common substance use disorder worldwide. Although dopamine-related findings were often observed in AUD, associated neurobiological mechanisms are still poorly understood. Therefore, in the present study, we investigate D2/3 receptor availability in healthy participants, participants at high risk (HR) to develop addiction (not diagnosed with AUD), and AUD patients in a detoxified stage, applying F-18-fallypride positron emission tomography (F-18-PET). Specifically, D2/3 receptor availability was investigated in (1) 19 low-risk (LR) controls, (2) 19 HR participants, and (3) 20 AUD patients after alcohol detoxification. Quality and severity of addiction were assessed with clinical questionnaires and (neuro)psychological tests. PET data were corrected for age of participants and smoking status. In the dorsal striatum, we observed significant reductions of D2/3 receptor availability in AUD patients compared with LR participants. Further, receptor availability in HR participants was observed to be intermediate between LR and AUD groups (linearly decreasing). Still, in direct comparison, no group difference was observed between LR and HR groups or between HR and AUD groups. Further, the score of the Alcohol Dependence Scale (ADS) was inversely correlated with D2/3 receptor availability in the combined sample. Thus, in line with a dimensional approach, striatal D2/3 receptor availability showed a linear decrease from LR participants to HR participants to AUD patients, which was paralleled by clinical measures. Our study shows that a core neurobiological feature in AUD seems to be detectable in an early, subclinical state, allowing more individualized alcohol prevention programs in the future.
In nature, plants are constantly exposed to many transient, but recurring, stresses. Thus, to complete their life cycles, plants require a dynamic balance between capacities to recover following cessation of stress and maintenance of stress memory. Recently, we uncovered a new functional role for macroautophagy/autophagy in regulating recovery from heat stress (HS) and resetting cellular memory of HS inArabidopsis thaliana. Here, we demonstrated that NBR1 (next to BRCA1 gene 1) plays a crucial role as a receptor for selective autophagy during recovery from HS. Immunoblot analysis and confocal microscopy revealed that levels of the NBR1 protein, NBR1-labeled puncta, and NBR1 activity are all higher during the HS recovery phase than before. Co-immunoprecipitation analysis of proteins interacting with NBR1 and comparative proteomic analysis of annbr1-null mutant and wild-type plants identified 58 proteins as potential novel targets of NBR1. Cellular, biochemical and functional genetic studies confirmed that NBR1 interacts with HSP90.1 (heat shock protein 90.1) and ROF1 (rotamase FKBP 1), a member of the FKBP family, and mediates their degradation by autophagy, which represses the response to HS by attenuating the expression ofHSPgenes regulated by the HSFA2 transcription factor. Accordingly, loss-of-function mutation ofNBR1resulted in a stronger HS memory phenotype. Together, our results provide new insights into the mechanistic principles by which autophagy regulates plant response to recurrent HS.
Induced point mutations are important genetic resources for their ability to create hypo- and hypermorphic alleles that are useful for understanding gene functions and breeding. However, such mutant populations have only been developed for a few temperate maize varieties, mainly B73 and W22, yet no tropical maize inbred lines have been mutagenized and made available to the public to date. We developed a novel Ethyl Methanesulfonate (EMS) induced mutation resource in maize comprising 2050 independent M2 mutant families in the elite tropical maize inbred ML10. By phenotypic screening, we showed that this population is of comparable quality with other mutagenized populations in maize. To illustrate the usefulness of this population for gene discovery, we performed rapid mapping-by-sequencing to clone a fasciated-ear mutant and identify a causal promoter deletion in ZmCLE7 (CLE7). Our mapping procedure does not require crossing to an unrelated parent, thus is suitable for mapping subtle traits and ones affected by heterosis. This first EMS population in tropical maize is expected to be very useful for the maize research community. Also, the EMS mutagenesis and rapid mapping-by-sequencing pipeline described here illustrate the power of performing forward genetics in diverse maize germplasms of choice, which can lead to novel gene discovery due to divergent genetic backgrounds.
In this study, the synthesis of new 5 (2-x-phenyl)-N,N-dimethyl-2H-tetrazole-2-carboxamides (X = H and Cl) is reported coupled with the investigation of their dynamic H-1-NMR via rotation about C-N bonds in the moiety of urea group [a; CO-NMe2] in DMSO solvent (298-373 K). Accordingly, activation free energies of 17.32 and 17.50 kcal mol(-1) were obtained for X = H and Cl respectively, with respect to the conformational isomerization about the Me2N-C=O bond (a rotation). Moreover, a and b [b; 2-tetrazolyl-CO rotations] barrier to rotations in 5-(2-x-phenyl)-N,N-dimethyl-2H-tetrazole-2-carboxamides were also calculated by B3LYP/6-311++G** procedure. The optimized geometry parameters are well consistent with the X-ray data. Computed rotational energy barriers (X = Cl) for a and b were estimated to be 17.52 and 2.53 kcal mol(-1), respectively, the former in agreement with the dynamic NMR results. X-ray structures verify that just 2-acylated tetrazoles are formed in the case of 5-(2-x-phenyl)-N,N-dimethyl-2H-tetrazole-2-carboxamides. A planar trigonal orientation of the Me2N group was proven by X-ray data, which is coplanar to the carbonyl group, coupled with partial double bond C-N character. This also illustrates the syn-periplanar position of the tetrazolyl ring with C=O group. In solution, the planes containing tetrazolyl ring and the carbonyl bond are almost perpendicular to each other (because of steric effects as confirmed by calculations) while the planes containing carbonyl bond and Me2N group are coplanar. This phenomenon is in contrast with similar urea derivatives and explains the reason for the unusually high rotational energy barrier of these compounds. (C) 2020 Elsevier B.V. All rights reserved.
This chapter compares East and West African English as two distinct regional varieties of African English. First, the historical development of English in these two regions is briefly considered. It is argued that British colonial policy contributed significantly to the sociolinguistic and, indirectly, even structural differences these varieties exhibit. Then, the discussion moves on to give a short overview of the national sub-varieties. It is found that, although united by common linguistic features, West African English is far more heterogeneous than East African English, and some explanation is provided for this phenomenon. Focusing specifically on phonetic features, the chapter summarizes and contrasts the main diagnostic and distinctive features of each regional variety, with special reference to the peculiarities of the national varieties of West African English. However, despite their structural differences, West African, East African English and, for that matter, Southern African English are rooted in a shared “African culture.” Recent findings are introduced, in which common conceptual and linguistic patterns pertaining to witchcraft, expressed in the regional varieties in question, are highlighted.
The increasing prevalence and ubiquity of digital technologies is changing the needs and expectations of patients towards healthcare services. As a result, a plethora of patient-centered services edges into the healthcare market. Since digital technologies bear the potential to surmount barriers in time and space, patients increasingly demand real-time or near-time healthcare services. Amongst a cloud of related concepts in the context of digital health, one term increasingly typifies this impulse: on-demand healthcare. While this term can be noticeably found in practice, there is hardly some theoretical foundation so far. Against this background, the aim of this paper is to address this research gap and to explore the phenomenon of on-demand healthcare. Based on a design-science approach including a literature review and analysis of in-depth interviews and empirical cases, the outcome of this paper is twofold: (1) a conceptual framework and (2) a proposal for a definition of on-demand healthcare.
Due to changing customer behavior in digitalization, banks urge to change their traditional value creation in order to improve interaction with customers. New digital technologies such as core banking solutions change organizational structures to provide organizational and individual affordances in IT-supported personal advisory. Based on adaptive structuration theory and with qualitative data from 24 German banks, we identify first, second and third order issues of organizational change in value creation, which are connected with a set of affordances and constraints as the outcomes for customer interaction.
Increasingly, research attention is being afforded to various forms of problematic media use. Despite ongoing conceptual, theoretical, and empirical debates, a large number of retrospective self-report scales have been produced to ostensibly measure various classes of such behaviour. These scales are typically based on a variety of theoretical and diagnostic frameworks. Given current conceptual ambiguities, building on previous studies, we evaluated the dimensional structure of 50 scales targeting the assessment of supposedly problematic behaviours in relation to four technologies: Internet, smartphones, video games, and social network sites. We find that two dimensions (‘compulsive use’ and ‘negative outcomes’) account for over 50% of all scale-items analysed. With a median of five dimensions, on average, scales have considered fewer dimensions than various proposed diagnostic criteria and models. No relationships were found between the number of items in a scale and the number of dimensions, or the technology category and the dimensional structure. The findings indicate, firstly, that a majority of scales place an inordinate emphasis on some dimensions over others and, secondly, that despite differences in the items presented, at a dimensional level, there exists a high degree of similarity between scales. These findings highlight shortcomings in existing scales and underscore the need to develop more sophisticated conceptions and empirical tools to understand possible problematic interactions with various digital technologies.