Filtern
Erscheinungsjahr
- 2017 (1963) (entfernen)
Dokumenttyp
- Wissenschaftlicher Artikel (1310)
- Postprint (237)
- Dissertation (182)
- Sonstiges (114)
- Rezension (50)
- Monographie/Sammelband (20)
- Teil eines Buches (Kapitel) (19)
- Konferenzveröffentlichung (7)
- Habilitation (4)
- Masterarbeit (4)
Sprache
- Englisch (1963) (entfernen)
Schlagworte
- Germany (16)
- climate change (14)
- Holocene (11)
- climate (11)
- stars: massive (11)
- German (10)
- adolescence (9)
- young athletes (9)
- Arabidopsis (8)
- ancient DNA (8)
Institut
- Institut für Biochemie und Biologie (367)
- Institut für Geowissenschaften (294)
- Institut für Physik und Astronomie (276)
- Institut für Chemie (150)
- Department Psychologie (113)
- Department Sport- und Gesundheitswissenschaften (89)
- Institut für Ernährungswissenschaft (73)
- Mathematisch-Naturwissenschaftliche Fakultät (72)
- Institut für Mathematik (60)
- Department Linguistik (58)
Handling manufacturing and aging faults with software-based techniques in tiny embedded systems
(2017)
Non-volatile memory area occupies a large portion of the area of a chip in an embedded system. Such memories are prone to manufacturing faults, retention faults, and aging faults. The paper presents a single software based technique that allows for handling all of these fault types in tiny embedded systems without the need for hardware support. This is beneficial for low-cost embedded systems with simple memory architectures. A software infrastructure and a flow are presented that demonstrate how the presented technique is used in general for fault handling right after manufacturing and in-the-field. Moreover, a full implementation is presented for a MSP430 microcontroller, along with a discussion of the performance, overhead, and reliability impacts.
This paper describes architectural extensions for a dynamically scheduled processor, so that it can be used in three different operation modes, ranging from high-performance, to high-reliability. With minor hardware-extensions of the control path, the resources of the superscalar data-path can be used either for high-performance execution, fail-safe-operation, or fault-tolerant-operation. This makes the processor-architecture a very good candidate for applications with dynamically changing reliability requirements, e.g. for automotive applications. The paper reports the hardware-overhead for the extensions, and investigates the performance penalties introduced by the fail-safe and fault-tolerant mode. Furthermore, a comprehensive fault simulation was carried out in order to investigate the fault-coverage of the proposed approach.
Embedded smart home
(2017)
The popularity of MOOCs has increased considerably in the last years. A typical MOOC course consists of video content, self tests after a video and homework, which is normally in multiple choice format. After solving this homeworks for every week of a MOOC, the final exam certificate can be issued when the student has reached a sufficient score. There are also some attempts to include practical tasks, such as programming, in MOOCs for grading. Nevertheless, until now there is no known possibility to teach embedded system programming in a MOOC course where the programming can be done in a remote lab and where grading of the tasks is additionally possible. This embedded programming includes communication over GPIO pins to control LEDs and measure sensor values. We started a MOOC course called "Embedded Smart Home" as a pilot to prove the concept to teach real hardware programming in a MOOC environment under real life MOOC conditions with over 6000 students. Furthermore, also students with real hardware have the possibility to program on their own real hardware and grade their results in the MOOC course. Finally, we evaluate our approach and analyze the student acceptance of this approach to offer a course on embedded programming. We also analyze the hardware usage and working time of students solving tasks to find out if real hardware programming is an advantage and motivating achievement to support students learning success.
Moving Forces
(2017)
Throughout a large part of the twentieth century, the body was interpreted as a field of signs, the meaning of which pointed to an unconscious dimension. At the height of the popularity of structuralism, Jacques Lacan deemed the unconscious to be “structured like a language.” Starting in the early 1990s, however, a deep shift occurred in the way the body was interpreted. A new movement cast tremendous doubt on the hegemony of language and instead advocated a performative, pictorial, and affective approach — the so-called material turn — which encompassed all of these. In the words of Karen Barad, this turn inquired as to why meaning, history, and truth are assigned to language only, whereas the movements of materiality are given less prominence: “How did language come to be more trustworthy than matter? Why are language and culture granted their own agency and historicity while matter is figured as passive and immutable?” With this shift toward the material, bodies began to be seen in a different light and their materiality understood as something that follows its own laws and movements, which cannot be understood exclusively in terms of social-cultural codes. Instead, these laws and movements call into question the very dichotomies of nature/culture and body/spirit.
The design of embedded systems is becoming continuously more complex such that efficient system-level design methods are becoming crucial. Recently, combined Answer Set Programming (ASP) and Quantifier Free Integer Difference Logic (QF-IDL) solving has been shown to be a promising approach in system synthesis. However, this approach still has several restrictions limiting its applicability. In the paper at hand, we propose a novel ASP modulo Theories (ASPmT) system synthesis approach, which (i) supports more sophisticated system models, (ii) tightly integrates the QF-IDL solving into the ASP solving, and (iii) makes use of partial assignment checking. As a result, more realistic systems are considered and an early exclusion of infeasible solutions improves the entire system synthesis.
Massive Open Online Courses (MOOCs) have left their mark on the face of education during the recent years. At the Hasso Plattner Institute (HPI) in Potsdam, Germany, we are actively developing a MOOC platform, which provides our research with a plethora of e-learning topics, such as learning analytics, automated assessment, peer assessment, team-work, online proctoring, and gamification. We run several instances of this platform. On openHPI, we provide our own courses from within the HPI context. Further instances are openSAP, openWHO, and mooc.HOUSE, which is the smallest of these platforms, targeting customers with a less extensive course portfolio. In 2013, we started to work on the gamification of our platform. By now, we have implemented about two thirds of the features that we initially have evaluated as useful for our purposes. About a year ago we activated the implemented gamification features on mooc.HOUSE. Before activating the features on openHPI as well, we examined, and re-evaluated our initial considerations based on the data we collected so far and the changes in other contexts of our platforms.
Becoming a Student of Reform
(2017)
Preface
(2017)
Drug target miRNA
(2017)
This volume provides a concise and technical discussion of recently developed approaches to overcome challenges in miRNA drug discovery. Drug Target miRNA: Methods and Protocols explores strategies to overcome pharmacodynamics and pharmacokinetics challenges. These strategies cover anti-sense agents targeting miRNA that are applied in advanced formulations or are chemically optimized to increase delivery; small molecule miRNA modulators to overcome anti-sense agents’ limitations; general enhancers of miRNA maturation; and Argonaute 2 protein and its pharmacokinetic parameters. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls.Cutting-edge and thorough, Drug Target miRNA: Methods and Protocols is a valuable resource for anyone interested in the ever-evolving field of miRNA drug discovery.
The paper deals with the increasing growth of embedded systems and their role within structures similar to the Internet (Internet of Things) as those that provide calculating power and are more or less appropriate for analytical tasks. Faced with the example of a cyber-physical manufacturing system, a common objective function is developed with the intention to measure efficient task processing within analytical infrastructures. A first validation is realized on base of an expert panel.
Many markets are characterized by pricing competition. Typically, competitors are involved that adjust their prices in response to other competitors with different frequencies. We analyze stochastic dynamic pricing models under competition for the sale of durable goods. Given a competitor’s pricing strategy, we show how to derive optimal response strategies that take the anticipated competitor’s price adjustments into account. We study resulting price cycles and the associated expected long-term profits. We show that reaction frequencies have a major impact on a strategy’s performance. In order not to act predictable our model also allows to include randomized reaction times. Additionally, we study to which extent optimal response strategies of active competitors are affected by additional passive competitors that use constant prices. It turns out that optimized feedback strategies effectively avoid a decline in price. They help to gain profits, especially, when aggressive competitor s are involved.
Coring on Digital Platforms
(2017)
Today’s mobile devices are part of powerful business ecosystems, which usually involve digital platforms. To better understand the complex phenomenon of coring and related dynamics, this paper presents a case study comparing iMessage as part of Apple’s iOS and WhatsApp. Specifically, it investigates activities regarding platform coring, as the integration of several functionalities provided by third-party applications in the platform core. The paper makes three contributions. First, a systematization of coring activities is developed. Coring modes are differentiated by the amount of coring and application maintenance. Second, the case study revealed that the phenomenon of platform coring is present on digital platforms for mobile devices. Third, the fundamentals of coring are discussed as a first step towards theoretical development. Even though coring constitutes a potential threat for third-party developers regarding their functional differentiation, an idea of what a beneficial partnership incorporating coring activities could look like is developed here.
The ecological benefits of polyploidy are intensely debated. Some authors argue that plants with duplicated chromosome sets (polyploids) are more stress- resistant and superior colonizers and may thus outnumber their low ploidy conspecifics in more extreme habitats. Brachypodium distachyon (sensu lato), for example, a common annual grass in Israel and the entire Mediterranean basin, comprises three cytotypes of differing chromosome numbers that were recently proposed as distinct species. It was suggested that increased aridity increases the occurrence of its polyploid cytotype. Here, we tested at two spatial scales whether polyploid plants of B. distachyon s. l. are more frequently found in drier habitats in Israel. We collected a total of 430 specimens (i) along a largescale climatic gradient with 15 thoroughly selected sites (spanning 114- 954 mm annual rainfall), and (ii) from corresponding Northern (more mesic) and Southern (more arid) hill slopes to assess the micro- climatic difference between contrasting exposures. Cytotypes were then determined via flow cytometry. Polyploid plants comprised 90% of all specimens and their proportion ranged between 0% and 100% per site. However, this proportion was not correlated with aridity along the large- scale gradient, nor were polyploids more frequently found on Southern exposures. Our results show for both spatial scales that increasing aridity is not the principal driver for the distribution of polyploids in B. distachyon s. l. in Israel. Notably, though, diploid plants were restricted essentially to four intermediate sites, while polyploids dominated the most arid and the most mesic sites. This, to some degree, clustered pattern suggests that the distribution of cytotypes is not entirely random and calls for future studies to assess further potential drivers.
In this paper, using an algorithm based on the retrospective rejection sampling scheme introduced in [A. Beskos, O. Papaspiliopoulos, and G. O. Roberts,Methodol. Comput. Appl. Probab., 10 (2008), pp. 85-104] and [P. Etore and M. Martinez, ESAIM Probab.Stat., 18 (2014), pp. 686-702], we propose an exact simulation of a Brownian di ff usion whose drift admits several jumps. We treat explicitly and extensively the case of two jumps, providing numerical simulations. Our main contribution is to manage the technical di ffi culty due to the presence of t w o jumps thanks to a new explicit expression of the transition density of the skew Brownian motion with two semipermeable barriers and a constant drift.
Birds migrating across the Himalayan region fly over the highest peaks in the world, facing immense physiological and climatic challenges. The authors show the different strategies used by birds to cope with these challenges. Many wetland avian species are seen in the high-altitude lakes of the Himalayas and the adjoining Tibetan Plateau, such as Bar-Headed Geese. Ringing programmes have generated information about origins and destinations, and this book is the first to present information on the bird's exact migratory paths. Capitalising on knowledge generated through satellite telemetry, the authors describe the migratory routes of a multitude of birds flying over or skirting the Himalayas. The myriad of threats to migratory birds and the wetland system in the Central Asian Flyway are discussed, with ways to mitigate them. This volume will inform and persuade policy-makers and conservation practitioners to take appropriate measures for the long-term survival of this unique migration
The phylogenetic structure of communities (PSC) reveals how evolutionary history affects community assembly processes. However, there are important knowledge gaps on PSC patterns for annual communities and there is a need for studies along environmental gradients in dry ecosystems where several processes shape PSC. Here, we investigated the PSC of annual plants along an aridity gradient in Israel, including eight years, two spatial scales, the effects of shrubs on understory, and the phylogenetic signal of important traits. Increasing drought stress led to overdispersed PSC at the drier end of the gradient, indicating that species were less related than expected by chance. This was supported at a smaller spatial scale, where within the drier sites, communities in open- more arid- habitats were more overdispersed than those under nurse shrubs. Interestingly, some key traits related to drought resistance were not conserved in the phylogeny. Together, our findings suggested that while habitat filtering selected for drought resistance strategies, these strategies evolved independently along multiple contrasting evolutionary lineages. Our comprehensive PSC study provides strong evidence for the interacting effects of habitat filtering and plant- plant interactions, particularly highlighting that the conservative evolution of traits should not be assumed in future interpretations of PSC patterns.
William S. Campbell’s research on the apostle Paul has been at the forefront of overcoming anti-Jewish interpretations. His career has been characterised by academic rigour and social and interfaith engagement. His interpretive approach is committed to formulating Christian identity in positive relation to others and thus contributes to provide a vital basis for Jewish-Christian and Interfaith relations in general for the future.
Purpose:
While industrial marketers have long bundled their products and services to sell them as packages, to what extent should negotiators also rely on packaging their offers? Clearly, negotiating at a package level can tax the cognitive capacity of the involved parties at some point. Therefore, this study aims to analyze the impact of the number and type of issues that should be negotiated simultaneously to leverage the package strategy efficiently and effectively in multi-issue buyer-seller negotiations.
Design/methodology/approach:
The authors conducted and analyzed negotiation simulations with 676 students from 2 public universities.
Findings:
The authors’ results suggest that negotiating three out of six issues simultaneously is the least efficient but most effective strategy in multi-issue buyer-seller negotiations. Moreover, they found that bundling distributive and integrative issues is more efficient and effective than only bundling distributive or integrative negotiation issues in a package offer.
Originality/value:
Past research has examined the impact of negotiating a package as compared to each issue separately; however, little empirical attention has been directed toward understanding how to apply a package strategy in complex multi-issue negotiations.
In this article, I deal with the concept of truth and lie in Jewish traditional literature, examining its development in the Hebrew Bible and rabbinic literature. An essential aspect in understanding this concept is the dualism of ‘good’ and ‘evil’ impulses and the free will of human beings, who were created in the image of God and have the choice to decide between right and wrong.
Particle filters (also called sequential Monte Carlo methods) are widely used for state and parameter estimation problems in the context of nonlinear evolution equations. The recently proposed ensemble transform particle filter (ETPF) [S. Reich, SIAM T. Sci. Comput., 35, (2013), pp. A2013-A2014[ replaces the resampling step of a standard particle filter by a linear transformation which allows for a hybridization of particle filters with ensemble Kalman filters and renders the resulting hybrid filters applicable to spatially extended systems. However, the linear transformation step is computationally expensive and leads to an underestimation of the ensemble spread for small and moderate ensemble sizes. Here we address both of these shortcomings by developing second order accurate extensions of the ETPF. These extensions allow one in particular to replace the exact solution of a linear transport problem by its Sinkhorn approximation. It is also demonstrated that the nonlinear ensemble transform filter arises as a special case of our general framework. We illustrate the performance of the second-order accurate filters for the chaotic Lorenz-63 and Lorenz-96 models and a dynamic scene-viewing model. The numerical results for the Lorenz-63 and Lorenz-96 models demonstrate that significant accuracy improvements can be achieved in comparison to a standard ensemble Kalman filter and the ETPF for small to moderate ensemble sizes. The numerical results for the scene-viewing model reveal, on the other hand, that second-order corrections can lead to statistically inconsistent samples from the posterior parameter distribution.
This survey provides an overview of topics related to the history of economics that have been discussed within the last two years in journal articles. The survey format has been started by History of Economic Ideas last year with the survey by Giulia Bianchi (2016) and is aimed to increase the visibility of research in the history of economics. The emphasis of our survey is on the big three journals in the history of economics: the European Journal of the History of Economic Thought, the Journal of the History of Economic Thought and History of Political Economy. We also included additional journals that frequently publish articles related to the history of economics. These include, in alphabetical order, the Cambridge Journal of Economics, Contributions to Political Economy, Economic Thought, the Erasmus Journal for Philosophy and Economics, History of Economic Thought and Policy, the History of Economics Review, the Journal of Economic Literature, the Journal of Economic Methodology, the Journal of Economic Perspectives, OE conomia, Oxford Economic Papers and Research in the History of Economic Thought and Methodology.
The ionospheric delay of global navigation satellite systems (GNSS) signals typically is compensated by adding a single correction value to the pseudorange measurement of a GNSS receiver. Yet, this neglects the dispersive nature of the ionosphere. In this context we analyze the ionospheric signal distortion beyond a constant delay. These effects become increasingly significant with the signal bandwidth and hence more important for new broadband navigation signals. Using measurements of the Galileo E5 signal, captured with a high gain antenna, we verify that the expected influence can indeed be observed and compensated. A new method to estimate the total electron content (TEC) from a single frequency high gain antenna measurement of a broadband GNSS signal is proposed and described in detail. The received signal is de facto unaffected by multi-path and interference because of the narrow aperture angle of the used antenna which should reduce the error source of the result in general. We would like to point out that such measurements are independent of code correlation, like in standard receiver applications. It is therefore also usable without knowledge of the signal coding. Results of the TEC estimation process are shown and discussed comparing to common TEC products like TEC maps and dual frequency receiver estimates.
Hulleman & Olivers' (H&O's) model introduces variation of the functional visual field (FVF) for explaining visual search behavior. Our research shows how the FVF can be studied using gaze-contingent displays and how FVF variation can be implemented in models of gaze control. Contrary to H&O, we believe that fixation duration is an important factor when modeling visual search behavior.
Computerised mirror therapy with Augmented Reflection Technology for early stroke rehabilitation
(2017)
Purpose: New rehabilitation strategies for post-stroke upper limb rehabilitation employing visual stimulation show promising results, however, cost-efficient and clinically feasible ways to provide these interventions are still lacking. An integral step is to translate recent technological advances, such as in virtual and augmented reality, into therapeutic practice to improve outcomes for patients. This requires research on the adaptation of the technology for clinical use as well as on the appropriate guidelines and protocols for sustainable integration into therapeutic routines. Here, we present and evaluate a novel and affordable augmented reality system (Augmented Reflection Technology, ART) in combination with a validated mirror therapy protocol for upper limb rehabilitation after stroke. Results: The results showed that the combination and application of the Berlin Protocol for Mirror Therapy together with ART was feasible for clinical use. This combination was integrated into the therapeutic plan of subacute stroke patients at the two clinical locations where the second part of this research was conducted. Conclusions: Our findings pave the way for using technology to provide mirror therapy in clinical settings and show potential for the more effective use of inpatient time and enhanced recoveries for patients. IMPLICATIONS FOR REHABILITATION Computerised Mirror Therapy is feasible for clinical use Augmented Reflection Technology can be integrated as an adjunctive therapeutic intervention for subacute stroke patients in an inpatient setting Virtual Rehabilitation devices such as Augmented Reflection Technology have considerable potential to enhance stroke rehabilitation
The profits of excludability and transferability in redistributive land reform in central Namibia
(2017)
Policies which redistribute property rights to land can improve the well-being of rural households and can have overall growth effects. In many cases, however, land reforms are driven mainly by politically justified objectives. Under such circumstances, little emphasis is placed on whether and, if so, how property rights can increase productivity. Following 18 years of land reform implementation in Namibia, we evaluated 65 beneficiaries in Namibia. We assess to which degree land rights affects their farm income. The study focuses on Namibia’s two main commercial land reform instruments, namely the Farm Unit Resettlement Scheme and the Affirmative Action Loan Scheme. We find evidence that the majority of land reform projects are not profitable. Further, our study confirms the importance of the right to restrict land access compared with the right to transfer. The long-term leasehold contract seemingly provides sufficient incentives to make productive use of the land.
A frequently mentioned if somewhat peripheral figure in the historiography of late nineteenth-century linguistics is the German sinologist and general linguist Georg von der Gabelentz (1840–1893). Today Gabelentz is chiefly remembered for several insights that proved to be productive in the development of subsequent schools and subdisciplines. In this paper, we examine two of these insights, his analytic and synthetic systems of grammar and his foundational work on typology. We show how they were intimately connected within his conception of linguistic research, and how this was in turn embedded in the tradition established by Wilhelm von Humboldt (1767–1835), especially as it was further developed by H. Steinthal (1823–1899). This paper goes beyond several previous works with a similar focus by drawing on a wider range of Gabelentz’ writings, including manuscript sources that have only recently been published, and by examining specific textual connections between Gabelentz and his predecessors.
From blind shorthand
(2017)
This essay explores the poetics of obscurity that informs Luis Chitarroni’s « unfinished novel » The No Variations. Focusing on the « reticent » erudition that distinguishes this text, my analysis examines its dialogue with the paradigm of Borges’ erudition and narrative poetics, as well as with certain « counter-Borgesian » constellations in recent Argentine literature. My reading aims to show how Chitarroni’s anti-novel reactivates a specific Argentinean tradition of productive illegibility while considering how it relates to the practices of « impediment » and « aesthetic reduction » that pervade modern art and literature.
The Internet can be considered as the most important infrastructure for modern society and businesses. A loss of Internet connectivity has strong negative financial impacts for businesses and economies. Therefore, assessing Internet connectivity, in particular beyond their own premises and area of direct control, is of growing importance in the face of potential failures, accidents, and malicious attacks. This paper presents CORIA, a software framework for an easy analysis of connectivity risks based on large network graphs. It provides researchers, risk analysts, network managers and security consultants with a tool to assess an organization's connectivity and paths options through the Internet backbone, including a user-friendly and insightful visual representation of results. CORIA is flexibly extensible in terms of novel data sets, graph metrics, and risk scores that enable further use cases. The performance of CORIA is evaluated by several experiments on the Internet graph and further randomly generated networks.
Editorial
(2017)
Photonic sensing in highly concentrated biotechnical processes by photon density wave spectroscopy
(2017)
Photon Density Wave (PDW) spectroscopy is introduced as a new approach for photonic sensing in highly concentrated biotechnical processes. It independently quantifies the absorption and reduced scattering coefficient calibration-free and as a function of time, thus describing the optical properties in the vis/NIR range of the biomaterial during their processing. As examples of industrial relevance, enzymatic milk coagulation, beer mashing, and algae cultivation in photo bioreactors are discussed.
miRNA Targeting Drugs
(2017)
Only 20 years after the discovery of small non-coding, single-stranded ribonucleic acids, so-called microRNAs (miRNAs), as post-transcriptional gene regulators, the first miRNA-targeting drug Miravirsen for the treatment of hepatitis C has been successfully tested in clinical Phase II trials. Addressing miRNAs as drug targets may enable the cure, or at least the treatment of diseases, which presently seems impossible. However, due to miRNAs’ chemical structure, generation of potential drug molecules with necessary pharmacokinetic properties is still challenging and requires a re-thinking of the drug discovery process. Therefore, this chapter highlights the potential of miRNAs as drug targets, discusses the challenges, and tries to give a complete overview of recent strategies in miRNA drug discovery.
In our search for new antiplasmodial agents, the CH2Cl2/CH3OH (1:1) extract of the roots of Tephrosia aequilata was investigated, and observed to cause 100% mortality of the chloroquine-sensitive (3D7) strain of Plasmodium falciparum at a 10 mg/mL concentration. From this extract three new chalconoids, E-2,6-dimethoxy-3,4-(2,2-dimethyl)pyranoretrochalcone (1, aequichalcone A), Z-2,6-dimethoxy-3,4-(2,2-dimethyl)pyranoretrochalcone (2, aequichalcone B), 4-ethoxy-3-hydroxypraecansone B (3, aequichalcone C) and a new pterocarpene, 3,4:8,9-dimethylenedioxy-6a,11a-pterocarpene (4), along with seven known compounds were isolated. The purified compounds were characterized by NMR spectroscopic and mass spectrometric analyses. Compound 1 slowly converts into 2 in solution, and thus the latter may have been enriched, or formed, during the extraction and separation process. The isomeric compounds 1 and 2 were both observed in the crude extract. Some of the isolated constituents showed good to moderate antiplasmodial activity against the chloroquine-sensitive (3D7) strain of Plasmodium falciparum.
Enzymes from the xanthine oxidase (XO) family of molybdenum enzymes are generally, with some exceptions, molybdenum iron–sulfur flavin hydroxylases. Mammalian xanthine oxidoreductase and aldehyde oxidase were among the first enzymes to be studied in detail more than 100 years ago and, surprisingly, they continue to be thoroughly studied in molecular detail with many open and unresolved questions remaining. Enzymes of the XO family are characterized by a molybdenum cofactor (Moco) active site with a MoVIOS(OH) ligand sphere where substrate hydroxylation of either aromatic or aliphatic carbon centers is catalyzed. During the reaction, electrons are transferred to the oxidizing substrate, most commonly O2 or NAD+, which react at the FAD site.
Bacterial Molybdoenzymes
(2017)
The biogenesis of molybdoenzymes is a cytoplasmic event requiring both the folded apoenzymes and the matured molybdenum cofactor. The structure and the complexity of the molybdenum cofactor varies in each molybdoenzyme family and consequently different accessory proteins are required for the maturation of the respective enzymes. Thus, for enzymes of both the DMSO reductase and xanthine oxidase families, specific chaperones exist which are dedicated to increase the stability and the folding of specific members of each family. In this review, we describe the role of these chaperones for molybdoenzyme maturation. We present a model which describes step by step the mechanism of the maturation of representative molybdoenzymes from each family.
The biosynthesis of the molybdenum cofactor (Moco) is highly conserved among all kingdoms of life. In all molybdoenzymes with the exception of nitrogenase, the molybdenum atom is coordinated to a dithiolene group present in the pterin-based 6-alkyl side chain of molybdopterin (MPT). In general, the biosynthesis of Moco can be divided into three steps in eukaryotes, and four steps in bacteria and archaea: (i) the starting point is the formation of the cyclic pyranopterin monophosphate (cPMP) from 5′GTP, (ii) in the second step the two sulfur molecules are inserted into cPMP leading to the formation of MPT, (iii) in the third step the molybdenum atom is inserted into molybdopterin to form Moco and (iv) additional modification of Moco occurs in bacteria and archaea with the attachment of a nucleotide (CMP or GMP) to the phosphate group of MPT, forming the dinucleotide variants of Moco. This review will focus on the biosynthesis of Moco in bacteria, humans and plants.
Fat loads were quantified for 2125 Yellow-browed Warblers Phylloscopus inornatus trapped at a stop-over site in Far East Russia during autumn migration. Flight ranges of 660-820km were estimated for the fattest individuals, suggesting that they would need to stop for refuelling at least six times to reach their wintering areas in South East Asia.
This study investigates the comprehension of wh-questions in individuals with aphasia (IWA) speaking Turkish, a non-wh-movement language, and German, a wh-movement language. We examined six German-speaking and 11 Turkish-speaking IWA using picture-pointing tasks. Findings from our experiments show that the Turkish IWA responded more accurately to both object who and object which questions than to subject questions, while the German IWA performed better for subject which questions than in all other conditions. Using random forest models, a machine learning technique used in tree-structured classification, on the individual data revealed that both the Turkish and German IWA’s response accuracy is largely predicted by the presence of overt and unambiguous case marking. We discuss our results with regard to different theoretical approaches to the comprehension of wh-questions in aphasia.
Effects of aging on lexical processing are well attested, but the picture is less clear for grammatical processing. Where age differences emerge, these are usually ascribed to working-memory (WM) decline. Previous studies on the influence of WM on agreement computation have yielded inconclusive results, and work on aging and subject-verb agreement processing is lacking. In two experiments (Experiment 1: timed grammaticality judgment, Experiment 2: self-paced reading + WM test), we investigated older (OA) and younger (YA) adults’ susceptibility to agreement attraction errors. We found longer reading latencies and judgment reaction times (RTs) for OAs. Further, OAs, particularly those with low WM scores, were more accepting of sentences with attraction errors than YAs. OAs showed longer reading latencies for ungrammatical sentences, again modulated by WM, than YAs. Our results indicate that OAs have greater difficulty blocking intervening nouns from interfering with the computation of agreement dependencies. WM can modulate this effect.
In the present study, we examined the relationships between motivational beliefs (self-efficacy, task value, and control of learning beliefs) and use of metacognitive learning strategies among teacher education students in Uganda. The sample comprised of 649 students selected from seven universities. Data were collected using several scales from the modified Motivated Strategies for Learning Questionnaire, and analysed using Structural Equation Modelling. Task value and self-efficacy independently and significantly predicted students’ reported use of metacognition. Students’ self-reported self-efficacy and task value explained 38% of the variance in their use of metacognition. The evidence suggests interventions aimed at improving teacher education students’ metacognitive skills to focus on enhancing their efficacy and value beliefs.
Anthropologists all over the world are discussing influences on individual height including quantity and quality of nutrition. To examine whether a relationship between nutritional components and height can be found this pilot study has been developed. The research samples consisted of 44 children (age 3–6 years) attending two different kindergartens in Germany. Height measurements were taken for each child. Furthermore the parents had to fill out a 24-hour questionnaire to document their children’s eating habits during the weekend. In order to standardize the measured height values z-scores were calculated with reference to the average height of the overall cohort. The results of correlation analysis indicate that height is not significantly related to any of the main nutritional components as protein (r = –0.148), carbohydrates (r = 0.126), fat (r = 0.107), fibre (r = –0.289), vitamin (r = 0.050), calcium (r = 0.110), potassium (r = 0.189) and overall calorie intake (r = 0.302). In conclusion, it can be stated that the quality of nutrition may not have a strong influence on individual height. However, due to the small sample size further research should be provided with a larger cohort of children to verify the present results.
The Bajgan Complex, one of the basement constituents of the arc massif in Iranian Makran forms a rugged, deeply incised terrain. The complex consists of pelitic schists with minor psammitic and basic schists, calc silicate rocks, amphibolites, marbles, metavolcanosediments, mafic and felsic intrusives as well as ultramafic rocks. Metapelitic rocks show an amphibolite facies regional metamorphism and contain garnet, biotite, white mica, quartz, albite ± rutile ± apatite. Thermobarometry of garnet schist yields pressure of more than 9 kbar and temperatures between 560 and 675 °C. The geothermal gradient obtained for the peak of regional metamorphism is 19 °C/km, corresponding to a depth of ca. 31 km. Replacement of garnet by chlorite and epidote suggest greenschist facies metamorphism due to a decrease in temperature and pressure through exhumation and retrograde metamorphism (370–450 °C and 3–6 kbar). The metapelitic rocks followed a ‘clockwise’ P–T path during metamorphism, consistent with thermal decline following tectonic thickening. The formation of medium-pressure metamorphic rocks is related to presence of active subduction of the Neotethys Oceanic lithosphere beneath Eurasia in the Makran.
A Gateway to the World
(2017)
In the second half of the 19th century, the French École centrale des arts et manufactures became one of the engineering schools that enjoyed a worldwide reputation. There were many foreigners among its students. This article focuses on the graduates born in the Ottoman Empire, particularly on Jews and Armenians. It analyses their backgrounds, their common features and their professional careers, tracing their links with other centraliens. The patterns in the Ottoman centraliens’ professional trajectories help us picture a world full of opportunities where highly qualified men could cross borders and build careers with ease, but where, at the same time, origins, allegiances, contacts and credentials mattered greatly.
Editorial Board
(2017)
Purpose - This study aims to investigate whether a team of females negotiates differently than a team of males, and whether (workplace) friendship moderates the relationship between single-gender team composition and negotiation outcomes. Design/methodology/approach - The authors used two laboratory studies and paired 216 MBA students into single-gender teams of friends and non-friends, and then engaged them in several dyadic multi-issue negotiations. Findings - The results show that on average, male teams of non-friends reached significantly better outcomes than female teams of non-friends. However, and interestingly, female teams of friends perform equally to male teams of friends. Research limitations/implications - The authors contribute both to the negotiations and the workplace friendship literature because very little research has examined negotiation among friends at work and in particular team negotiations. In addition, the authors also contribute to the literature on gender differences in negotiations because existing research has rarely examined the differences between all-male and all-female teams and especially the relationship between same-sex teams and their effects on negotiation outcomes. Practical implications - This research has clear implications to managers with regard to team composition. Specifically, a winning all-female team should not be changed! Originality/value - This is the first study to examine the relationship between workplace friendship, gender and negotiation outcomes.
Purpose - The purpose of this study is to analyze whether negotiators stick to one single negotiation style or whether their styles vary during the negotiation process. The paper seeks to identify different combinations of phase-specific negotiation styles and investigates the relationship between these combinations and negotiation performance and satisfaction. Design/methodology/approach - The study is based on a large online negotiation simulation that allows a phase-specific analysis of negotiation styles via an elaborate coding scheme. Findings - The findings reveal that negotiators generally do not limit themselves to a single negotiation style. Instead, they vary their style in the course of different negotiation phases. The authors distinguish between five distinct phase-specific negotiation style patterns that differ with regard to their impact on negotiation performance but not negotiation satisfaction. Practical implications - Negotiation practitioners get to know different phase-specific negotiation style patterns and get insights into which pattern is the most promising for negotiation performance. As a result, they can acquire this phase-specific negotiation style pattern to enhance their performance. Originality/value - The paper contributes to existing negotiation style literature, because it is the first to analyze negotiation styles from a phase-specific point of view.
microRNAs (miRNAs) have been identified as high-value drug targets. A widely applied strategy in miRNA inhibition is the use of antisense agents. However, it has been shown that oligonucleotides are poorly cell permeable because of their complex chemical structure and due to their negatively charged backbone. Consequently, the general application of oligonucleotides in therapy is limited. Since miRNAs’ functions are executed exclusively by the Argonaute 2 protein, we therefore describe a protocol for the design of a novel miRNA inhibitor class: antagonists of the miRNA-Argonaute 2 protein complex, so-called anti-miR-AGOs, that not only block the crucial binding site of the target miRNA but also bind to the protein’s active site. Due to their lower molecular weight and, thus, more drug-like chemical structure, the novel inhibitor class may show better pharmacokinetic properties than reported oligonucleotide inhibitors, enabling them for potential therapeutic use.