5,201 research outputs found

    Corporate Social Responsibility: the institutionalization of ESG

    Get PDF
    Understanding the impact of Corporate Social Responsibility (CSR) on firm performance as it relates to industries reliant on technological innovation is a complex and perpetually evolving challenge. To thoroughly investigate this topic, this dissertation will adopt an economics-based structure to address three primary hypotheses. This structure allows for each hypothesis to essentially be a standalone empirical paper, unified by an overall analysis of the nature of impact that ESG has on firm performance. The first hypothesis explores the evolution of CSR to the modern quantified iteration of ESG has led to the institutionalization and standardization of the CSR concept. The second hypothesis fills gaps in existing literature testing the relationship between firm performance and ESG by finding that the relationship is significantly positive in long-term, strategic metrics (ROA and ROIC) and that there is no correlation in short-term metrics (ROE and ROS). Finally, the third hypothesis states that if a firm has a long-term strategic ESG plan, as proxied by the publication of CSR reports, then it is more resilience to damage from controversies. This is supported by the finding that pro-ESG firms consistently fared better than their counterparts in both financial and ESG performance, even in the event of a controversy. However, firms with consistent reporting are also held to a higher standard than their nonreporting peers, suggesting a higher risk and higher reward dynamic. These findings support the theory of good management, in that long-term strategic planning is both immediately economically beneficial and serves as a means of risk management and social impact mitigation. Overall, this contributes to the literature by fillings gaps in the nature of impact that ESG has on firm performance, particularly from a management perspective

    Computertomographie-basierte Bestimmung von Aortenklappenkalk und seine Assoziation mit Komplikationen nach interventioneller Aortenklappenimplantation (TAVI)

    Get PDF
    Background: Severe aortic valve calcification (AVC) has generally been recognized as a key factor in the occurrence of adverse events after transcatheter aortic valve implantation (TAVI). To date, however, a consensus on a standardized calcium detection threshold for aortic valve calcium quantification in contrast-enhanced computed tomography angiography (CTA) is still lacking. The present thesis aimed at comparing two different approaches for quantifying AVC in CTA scans based on their predictive power for adverse events and survival after a TAVI procedure.   Methods: The extensive dataset of this study included 198 characteristics for each of the 965 prospectively included patients who had undergone TAVI between November 2012 and December 2019 at the German Heart Center Berlin (DHZB). AVC quantification in CTA scans was performed at a fixed Hounsfield Unit (HU) threshold of 850 HU (HU 850 approach) and at a patient-specific threshold, where the HU threshold was set by multiplying the mean luminal attenuation of the ascending aorta by 2 (+100 % HUAorta approach). The primary endpoint of this study consisted of a combination of post-TAVI outcomes (paravalvular leak ≄ mild, implant-related conduction disturbances, 30-day mortality, post-procedural stroke, annulus rupture, and device migration). The Akaike information criterion was used to select variables for the multivariable regression model. Multivariable analysis was carried out to determine the predictive power of the investigated approaches.   Results: Multivariable analyses showed that a fixed threshold of 850 HU (calcium volume cut-off 146 mm3) was unable to predict the composite clinical endpoint post-TAVI (OR=1.13, 95 % CI 0.87 to 1.48, p=0.35). In contrast, the +100 % HUAorta approach (calcium volume cut-off 1421 mm3) enabled independent prediction of the composite clinical endpoint post-TAVI (OR=2, 95 % CI 1.52 to 2.64, p=9.2x10-7). No significant difference in the Kaplan-Meier survival analysis was observed for either of the approaches.   Conclusions: The patient-specific calcium detection threshold +100 % HUAorta is more predictive of post-TAVI adverse events included in the combined clinical endpoint than the fixed HU 850 approach. For the +100 % HUAorta approach, a calcium volume cut-off of 1421 mm3 of the aortic valve had the highest predictive value.Hintergrund: Ein wichtiger Auslöser von Komplikationen nach einer Transkatheter-Aortenklappen-Implantation (TAVI) sind ausgeprĂ€gte Kalkablagerung an der Aortenklappe. Dennoch erfolgte bisher keine Einigung auf ein standardisiertes Messverfahren zur Quantifizierung der Kalklast der Aortenklappe in einer kontrastverstĂ€rkten dynamischen computertomographischen Angiographie (CTA). Die vorliegende Dissertation untersucht, inwieweit die Wahl des Analyseverfahrens zur Quantifizierung von Kalkablagerungen in der Aortenklappe die Prognose von Komplikationen und der Überlebensdauer nach einer TAVI beeinflusst.   Methodik: Der Untersuchung liegt ein umfangreicher Datensatz von 965 Patienten mit 198 Merkmalen pro Patienten zugrunde, welche sich zwischen 2012 und 2019 am Deutschen Herzzentrum Berlin einer TAVI unterzogen haben. Die Quantifizierung der Kalkablagerung an der Aortenklappe mittels CTA wurde einerseits mit einem starren Grenzwert von 850 Hounsfield Einheiten (HU) (HU 850 Verfahren) und andererseits anhand eines individuellen Grenzwertes bemessen. Letzterer ergibt sich aus der HU-DĂ€mpfung in dem Lumen der Aorta ascendens multipliziert mit 2 (+100 % HUAorta Verfahren). Der primĂ€re klinische Endpunkt dieser Dissertation besteht aus einem aus sechs Variablen zusammengesetzten klinischen Endpunkt, welcher ungewĂŒnschte Ereignisse nach einer TAVI abbildet (paravalvulĂ€re Leckage ≄mild, Herzrhythmusstörungen nach einer TAVI, Tod innerhalb von 30 Tagen, post-TAVI Schlaganfall, Ruptur des Annulus und Prothesendislokation). Mögliche Störfaktoren, die auf das Eintreten der Komplikationen nach TAVI Einfluss haben, wurden durch den Einsatz des Akaike Informationskriterium ermittelt. Um die Vorhersagekraft von Komplikationen nach einer TAVI durch beide Verfahren zu ermitteln, wurde eine multivariate Regressionsanalyse durchgefĂŒhrt.   Ergebnisse: Die multivariaten logistischen Regressionen zeigen, dass die Messung der Kalkablagerungen anhand der HU 850 Messung (Kalklast Grenzwert von 146 mm3) die Komplikationen und die Überlebensdauer nicht vorhersagen konnten (OR=1.13, 95 % CI 0.87 bis 1.48, p=0.35). Die nach dem +100 % HUAorta Verfahren (Kalklast Grenzwert von 1421 mm3) individualisierte Kalkmessung erwies sich hingegen als sehr aussagekrĂ€ftig, da hiermit Komplikationen nach einer TAVI signifikant vorhergesagt werden konnten (OR=2, 95 % CI 1.52 bis 2.64, p=9.2x10-7). In Hinblick auf die postoperative Kaplan-Meier Überlebenszeitanalyse kann auch mit dem +100 % HUAorta Verfahren keine Vorhersage getroffen werden.   Fazit: Aus der Dissertation ergibt sich die Empfehlung, die Messung von Kalkablagerungen nach dem +100 % HUAorta Verfahren vorzunehmen, da Komplikationen wesentlich besser und zuverlĂ€ssiger als nach der gĂ€ngigen HU 850 Messmethode vorhergesagt werden können. FĂŒr das +100 % HUAorta Verfahren lag der optimale Kalklast Grenzwert bei 1421 mm3

    Management controls, government regulations, customer involvement: Evidence from a Chinese family-owned business

    Get PDF
    This research reports on a case study of a family-owned elevator manufacturing company in China, where management control was sandwiched between the state policies and global customer production requirements. By analysing the role of government and customer, this thesis aimed to illustrate how management control operated in a family-owned business and to see how and why they do management control differently. In particular, it focused on how international production standards and existing Chinese industry policies translated into a set of the management control practices through a local network within the family-owned business I studied. Based on an ethnographic approach to research, I spent six months in the field, conducted over 30 interviews, several conservations, and reviewed relevant internal documents to understand how management control (MC) techniques with humans cooperated in the company. I also understood how two layers of pressure have shaped company behaviour, and how a company located in a developing country is connecting with global network. I also found there is considerable tension among key actors and investigated how the company responded and managed it. Drawing on Actor Network Theory (ANT), I analysed the interviews from key actors, examined the role of government regulations and customer requirements to see how management control being managed under two layers of pressure, i.e., the government regulations (e.g., labour, tax, environment control) and customer requirement (e.g., quality and production control). Management controls were an obligatory passage point (OPP), and transformation of those elements of Western production requirements and government requirements arrived at the Chinese local factory and influenced management control and budgeting. The findings suggest that management control systems are not only a set of technical procedures, but it is also about managing tensions. This understanding shows a linear perspective on MC practices rather than a social perspective. However, when we use ANT as a theoretical perspective, we see those actors who, being obliged and sandwiched, and controlled by external forces for them to follow. Consequently, human actors must work in an unavoidable OPP. This is the tension they face which constructed mundane practices of MC. Hence, MCs are managing such tensions. This study contributes to management control research by analysing management controls in terms of OPP, extends our understanding by illustrating the role of the government and customers, and our understanding of family-owned business from a management controls perspective in a developing country

    Graphical scaffolding for the learning of data wrangling APIs

    Get PDF
    In order for students across the sciences to avail themselves of modern data streams, they must first know how to wrangle data: how to reshape ill-organised, tabular data into another format, and how to do this programmatically, in languages such as Python and R. Despite the cross-departmental demand and the ubiquity of data wrangling in analytical workflows, the research on how to optimise the instruction of it has been minimal. Although data wrangling as a programming domain presents distinctive challenges - characterised by on-the-fly syntax lookup and code example integration - it also presents opportunities. One such opportunity is how tabular data structures are easily visualised. To leverage the inherent visualisability of data wrangling, this dissertation evaluates three types of graphics that could be employed as scaffolding for novices: subgoal graphics, thumbnail graphics, and parameter graphics. Using a specially built e-learning platform, this dissertation documents a multi-institutional, randomised, and controlled experiment that investigates the pedagogical effects of these. Our results indicate that the graphics are well-received, that subgoal graphics boost the completion rate, and that thumbnail graphics improve navigability within a command menu. We also obtained several non-significant results, and indications that parameter graphics are counter-productive. We will discuss these findings in the context of general scaffolding dilemmas, and how they fit into a wider research programme on data wrangling instruction

    The problem of hyperbolic discounting

    Get PDF

    Neurophysiological assessments of low-level and high-level interdependencies between auditory and visual systems in the human brain

    Get PDF
    This dissertation investigates the functional interplay between visual and auditory systems and its degree of experience-dependent plasticity. To function efficiently in everyday life, we must rely on our senses, building complex hierarchical representations about the environment. Early sensory deprivation, congenital (from birth) or within the first year of life, is a key model to study sensory experience and the degree of compensatory reorganizations (i.e., neuroplasticity). Neuroplasticity can be intramodal (within the sensory system) and crossmodal (the recruitment of deprived cortical areas for remaining senses). However, the exact role of early sensory experience and the mechanisms guiding experience-driven plasticity need further investigation. To this aim, we performed three electroencephalographic studies, considering the aspects: 1) sensory modality (auditory/visual), 2) hierarchy of the brain functional organization (low-/high-level), and 3)sensory deprivation (deprived/non-deprived cortices). The first study explored how early auditory experience affects low-level visual processing, using time-frequency analysis on the data of early deaf individuals and their hearing counterparts. The second study investigated experience- dependent plasticity in hierarchically organized face processing, applying fast periodic visual stimulation in congenitally deaf signers and their hearing controls. The third study assessed neural responses of blindfolded participants, using naturalistic stimuli together with temporal response function, and evaluated neural tracking in hierarchically organized speech processing when retinal input is absent, focusing on the role of the visual cortex. The results demonstrate the importance of atypical early sensory experience in shaping (via intra-and crossmodal changes) the brain organization at various hierarchical stages of sensory processing but also support the idea that some crossmodal effects emerge even with typical experience. This dissertation provides new insights into understanding the functional interplay between visual and auditory systems and the related mechanisms driving experience-dependent plasticity and may contribute to the development of sensory restoration tools and rehabilitation strategies for sensory-typical and sensory-deprived populations

    Evolutionary ecology of biological rhythms in malaria parasites

    Get PDF
    Biological rhythms are a ubiquitous feature of life and are assumed to allow organisms coordinate their activities with daily rhythms in the abiotic environment resulting from the rotation of the Earth every 24 hours. The genes and molecular mechanisms underpinning circadian clocks in multicellular organisms are relatively well understood in contrast to the evolution and ecology of circadian rhythms. Circadian rhythms mediate interactions between organisms; from predators and prey, to mating behaviours between males and females, to hosts and parasites. The role of daily rhythms in infections is gaining traction because explaining the regulatory mechanisms and fitness consequences of biological rhythms exhibited by parasites and hosts offers new avenues to treat infections. Here, I explore how periodicity in parasite traits is generated and why daily rhythms matter for parasite fitness. My work focuses on malaria (Plasmodium) parasites which exhibit developmental rhythms during replication in the mammalian host’s blood and during transmission to insect vectors. Rhythmic in-host parasite replication is responsible for eliciting inflammatory responses, severe anaemia, fuels transmission, and can confer tolerance to anti-parasite drugs. Thus, understanding both how and why the timing and synchrony of parasites are connected to the daily rhythms of hosts and vectors may make treatment more effective and less toxic to hosts. My papers integrate an evolutionary ecology approach with chronobiology and parasitology to investigate how host-parasite-vector interactions shape the evolution of rhythmicity in parasites traits. I have used a rodent malaria parasite model system (Plasmodium chabaudi) for my experiments, capitalising on the tractability of this model for the human malaria, P. falciparum. P. chabaudi exhibits a 24-hour rhythm in replication, facilitates ecologically realistic studies because experiments can be carried out in vivo (compared to the in vitro limitations on studying human parasites), and perturbations to the timing of the in-host and in-vector environments are straightforward. My findings include: 1) Perturbing the timing of parasite rhythms with respect to the timing of host rhythms (analogous to giving the parasites “jet lag”), results in a fitness cost to the parasites, evident by a 50% reduction in both asexually replicating and transmission stage parasites. 2) The consequences of temporal mismatch to the host manifest very early in the infection (within 48 hours, i.e. the first 1-2 cycles of replication) and are dependent on the parasite stage by which infections are initiated (0-12 hour old parasites suffer a cost, whereas 12-24 hour parasites benefit). 3) The timing of the parasite replication cycle is independent of the canonical ‘core’ host clock (i.e. transcription translation feedback loop) and instead depends on the timing of feeding-fasting rhythms of the host. 4) If perturbed, the timing of the parasite’s rhythm reschedules to regain synchrony with the timing of the host’s rhythm within 7 replication cycles. Specifically, parasites achieve this by speeding up the replication rhythm by 2-3 hours per cycle, and the rate of rescheduling is independent of parasite density. 5) Naturally asynchronous Plasmodium species are ‘resistant’ to conditions that lead to alignment with host rhythms in synchronously replicating species. This suggests that unknown ecological differences between these parasite species selects for vastly different schedules of within-host replication rather than some species being constrained to replicate asynchronously. 6) In addition to the timing of parasite rhythms impacting directly upon within-host dynamics, timing also matters – albeit indirectly - for transmission, via impacts on the population dynamics of the vector. For example, receiving a blood meal in the morning makes mosquitoes more likely to lay eggs, lay slightly sooner and have a larger clutch size than those feeding at night. Yet, whilst mosquitoes infected with malaria die sooner, the effects of taking a blood meal at different times of day do not impact transmission of an asynchronously replicating malaria parasite. It is beneficial for parasites to be in synchronization with their host’s feeding-fasting rhythms and plasticity in the IDC duration facilitates this synchrony by enabling parasites to make small daily changes to their IDC schedule when necessary. Understanding the extent of, and limits on, plasticity in the IDC schedule is important as it may reveal targets for novel interventions, such as drugs to disrupt IDC regulation and preventing IDC dormancy conferring tolerance to existing drugs. More generally, our results provide a demonstration of the adaptive value of biological rhythms and the utility of using an evolutionary framework to understand parasite traits

    Rethinking established methodology in micromammal taphonomy: archaeological case studies from Orkney, UK (4th millennium BC – 15th century AD)

    Get PDF
    Micromammals (e.g. rodents, shrews), characterised by their small size, short lifespan and high reproduction rate, are known for rapid adaptability to changing conditions, inhabiting all environments besides the most frigid. They form a variety of relationships with other animals as well as humans, from being prey up to mutualism, commensalism and even taming and domestication. Changes occurring short or long-term within micromammal populations can be a useful proxy for natural as well as human-induced changes. However, their remains from archaeological contexts have seldom been investigated, with a scarcity of methodological studies and incomparability of published data often discouraging research. Human impact on the environment is especially noticeable in the case of insular environments where humans are responsible for the majority of species introductions. This thesis examines a series of case studies from the Orkney islands off north-east Scotland to develop a micromammal zooarchaeological methodology and investigate the micromammal relationships with predators and human activity in this context. Specifically it has two main aims: 1) perform methodological research on obtained data to investigate established methods as well as to suggest new approaches to data analysis given what data are retrievable from studied assemblages; 2) apply the revised methodology to investigate a range of Orcadian sites, covering two main time periods of intensification of maritime contacts: Neolithic (4000 – 2000 BC) and Norse/mediaeval (600 – 1500 AD) ages. Analysis standardisation and reproducibility through coding in R is also introduced to deal with the large breath of obtained data. The study provides conclusive results, broadening the understanding of micromammal taphonomy and a range of different assemblages and deposition patterns present within and around anthropic contexts. The breath of utilizable data retrievable from micromammal assemblages is comparable with typical zooarchaeological research on the remains of bigger species, for example including information on age of death or non-predatory taphonomic factors. Spatial and contextual data, particularly, proves to be crucial for understanding the impact of dispersal and burial processes on micromammal accumulations. Moreover, the necessity for consistent sieving is confirmed, lower effort sampling or sieving regimes failing to provide representative and comparable samples. The obtained data can be effectively analysed through statistical methods, including classifying algorithms, bypassing problems encountered in the case of multiple comparisons and deposition patterns. However, the results also show that actualistic research may not be directly comparable with archaeological material without considering non-predatory taphonomic factors and their impact on data representativeness. Assemblages identified within the studied sites seem to be formed by a variety of factors. Identifiable predatory depositions could be attributed to both owls and diurnal raptors, taxa expected to be found considering modern Orkney fauna and dominant micromammal predators. Cases of non-predatory depositions included deaths of commensal species living and/or nesting within the anthropic environment, self-entrapment in anthropic features such as trenches or pits of single individuals and secondary accumulation in similar features due to dispersal. In general, each site shows multiple different patterns being present, with certain areas or context types (e.g. open/enclosed, natural/usage period/abandonment) exhibiting a predominance of a specific deposition. Intrusiveness is surprisingly rare and, where identified, is characterised by multiple intrusive species within the contexts, with singular species intrusiveness rarely being noted. Some evidence for human interaction with micromammals, direct or indirect, can be noted through additional taphonomic marks such as burning. However, a definitive interpretation of these marks, as of now, cannot be achieved

    Real-time fMRI connectivity neurofeedback for modulation of the motor system

    Get PDF
    Advances in functional magnetic resonance imaging (fMRI) have enabled an understanding of the neural mechanisms underlying human brain functions such as motor functions. In recent decades fMRI, which is a non-invasive and highresolution technique, has been used to investigate the functions of the human brain using the blood oxygen level dependent (BOLD) response as an indirect measurement of brain neural activities. Real-time fMRI (rt-fMRI) has been used as neurofeedback to enable individuals to regulate their neural activity to achieve improvements in their health and performance, such as their motor performance. Neurofeedback can be defined as the measurement of the neural activity of a participant that is presented to them as visual or auditory signals that enable self-regulation of neural activity. Rt-fMRI has also been used to provide feedback about the connectivity between brain regions. Such connectivity neurofeedback can be a more effective feedback strategy than providing feedback from a single region. Recently, connectivity neurofeedback has been explored to examine how functional connectivity of cortical areas and subcortical areas of the brain can be modulated. Enhancing connectivity between cortical and subcortical regions holds promise for the improvement of performance, particularly motor function performance. The aim of this PhD research was to modulate connectivity neurofeedback by using real-time fMRI neurofeedback (rt-fMRI-NF) between brain regions and to investigate whether any possible enhancement in the activation due to a successful fMRI-NF will translate into changes in behavioural measures. The thesis research began with experimental work to establish the experimental paradigm. This included work, using fMRI, to develop and test localisers for different motor areas such as primary motor cortex (M1), supplementary motor cortex (SMA), the motor cerebellum and the motor thalamus. The results showed that the execution of actions, such as hand clenching, can be used to functionally activate many motor areas including M1, SMA and the cerebellum. The motor thalamus was localised using a motor thalamus mask that was created offline using the Talairach atlas. All localisers tested in this research were feasible and able to be used for applications such as rt-fMRI-NF research to define the regions of interest. The first rt-fMRI connectivity neurofeedback experimental study of this thesis was conducted to determine whether healthy participants can use neurofeedback to enhance the connectivity between M1 and the thalamus using rt-fMRI. It also aimed to investigate whether successful rt-fMRI-NF of M1- thalamus connectivity could translate into changes in behavioural measures. For this purpose, the behavioural tasks were conducted before and after each MRI session. Two behavioural tasks were used in this experiment: Go/No Go and switching tasks. The results of this experiment showed a significant increase in connectivity neurofeedback in the experimental group (M1-thalamus), hence, rt-fMRI-NF is a useful tool to modulate functional connectivity between M1 and the thalamus using motor imagery and it facilitates the learning by participants of new mental strategies to upregulate M1-thalamus connectivity. The behavioural tasks showed a significant reduction in the switching time in the experimental group while Go/No Go task did not show a significant reduction in the reaction time in the experimental group. The second rt-fMRI connectivity neurofeedback experimental study of this thesis was conducted to investigate the ability of neurofeedback to modulate M1-cerebellum connectivity using motor imagery based rt-fMRI-NF. The results of this research showed enhanced connectivity between M1 and the cerebellum in each participant. However, this enhancement was not statistically significant. In summary, this PhD thesis extends and validates the usefulness of connectivity neurofeedback using motor imagery based rt-fMRI to modulate the correlation between cortical and subcortical brain regions. Successful modulation using this technique has the potential to lead to an enhancement in motor functions. Thereby, the results of this PhD research may help to advance connectivity neurofeedback for use as a supplementary treatment for many brain disorders such as stroke recovery and Parkinson’s disease
    • 

    corecore