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1

O'Cathain, Alicia. Rationales for using qualitative research with RCTs. Edited by Alicia O'Cathain. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198802082.003.0001.

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The focus of this chapter is on why researchers may want to use qualitative research with randomized controlled trials (RCTs) to generate evidence of effectiveness. The chapter starts by offering definitions of qualitative research and randomized controlled trials. It then moves on to exploring the types of interventions and contexts where qualitative research may be of most value. Ten rationales for combining qualitative research with RCTs are explored, followed by exploration of concerns researchers have expressed about this endeavour. Finally, the relevance of qualitative research to different fields of health research is considered.
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Felde, Andrea Kronstad, Tor Halvorsen, Anja Myrtveit, and Reidar Øygard. Democracy and the Discourse on Relevance Within the Academic Profession at Makerere University. African Minds, 2021. http://dx.doi.org/10.47622/9781928502272.

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Democracy and the Discourse of Relevanceis set against the backdrop of the spread of neoliberal ideas and reforms since the 1980s, accepting also that these ideas are rooted in a longer history. It focuses on how neoliberalism has worked to transform the university sector and the academic profession. In particular, it examines how understandings of, and control over, what constitutes relevant knowledge have changed. Taken as a whole, these changes have sought to reorient universities and academics towards economic development in various ways. This includes the installation of strategies for how institutions and academics achieve recognition and status within the academy, the privatisation of educational services and the downgrading of the value of public higher education, as well as a steady shift away from the public funding for universities. Research universities are increasingly adopting a user- and market-oriented model, with an emphasis on meeting corporate demands, the privileging of short-term research, and a strong tendency to view utility, and the potential to sell intellectual property for profit, as primary criteria for determining the relevance of academic knowledge. The privatisation of education services and the reorienting of universities towards the needs of the ‘knowledge economy’ have largely succeeded in transforming the discourse around the role of the academic profession in society, including in many African countries. Makerere University in Uganda has often been lauded as an example of successful transformation along neoliberal lines. However, our research into the working lives of academics at Makerere revealed a very different picture. Far from epitomising the allegedly positive outcomes of neoliberal reform, academics and postgraduate students interviewed at Makerere provide worrying insights into the undermining of a vibrant and independent academic culture. The stories of the ordinary academics on the ground, the empirical focus of the book, are in contrast to the claimed successes of the university; and the official stories of the university leadership and administration paint a picture of an academic profession in crisis. With diminishing influence on deciding what is relevant knowledge and thus on processes of democratization of their own institution and society, academic freedom is also losing its value. This perspective from the ground-level exposes the many problems that neoliberal reforms have created for academics at Makerere, leaving them feeling disempowered, often reducing them to the status of consultants. We also show how a range of local initiatives ­are steadily increasing resistance to the neoliberal model. We consider how academics and others can further mobilise to regain control over what knowledge is considered relevant, and thereby deepen democracy. In so doing, we aim to highlight some responses and actions that have proven effective so far. Democracy and the Discourse of Relevancewill hopefully help to change the systems that value knowledge in ways that are driving research institutions towards competitive and market-like behaviour. We also aim to contribute to contemporary debates about what knowledge is relevant.
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Ramanadhan, Shoba, Racquel E. Kohler, and K. Viswanath. Partnerships and Networks to Support Implementation Science. Edited by David A. Chambers, Wynne E. Norton, and Cynthia A. Vinson. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190647421.003.0038.

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Partnerships between researchers and stakeholders offer an opportunity to bring scientific and practice-based knowledge and experience together to improve the quality, value, and relevance of implementation science efforts and increase the application of findings. The chapter covers (1) a continuum of engagement for research–practice partnerships, including the benefits and challenges of engaged implementation science; (2) challenges and opportunities for partnerships in implementation science in community, policy, public opinion, and public–private partnership domains; (3) implementation science partnership evaluation, with an emphasis on social network analysis; and (4) a series of questions for the field as increasing attention is paid to partnerships for implementation science.
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Staley, Kent W. Decisions, Decisions. Oxford University Press, 2017. http://dx.doi.org/10.1093/acprof:oso/9780190467715.003.0003.

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Much of the discussion of the argument from inductive risk (AIR) centers on scientific research that has relevance to policymaking. To emphasize that inductive risk pervades science, this chapter discusses the AIR in the context of high energy physics: specifically, the discovery of the Higgs boson, a scientific finding that is irrelevant to policy. The applicability of the AIR for the case of the Higgs boson is established through a pragmatic approach to scientific inquiry, emphasizing the centrality of practical decision problems to the production of scientific knowledge. This approach, drawing on debates among pragmatists over the interpretation of statistical inference, eschews the classification of value judgments into epistemic and non-epistemic.
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McComas, Alan J. Aranzio's Seahorse and the Search for Memory and Consciousness. Oxford University PressOxford, 2022. http://dx.doi.org/10.1093/oso/9780192868244.001.0001.

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Abstract Completing a neuroscience trilogy, prize-winning author Alan McComas recounts the research that led to the hippocampus, a structure deep within the brain, as being primarily responsible for memory. The intriguing and exciting account includes observations on patients with memory loss as well as insights from ingenious laboratory experiments. Using several arguments, McComas suggests that it is the electrical activity of neurons in the hippocampus that creates consciousness and that the latter is, in fact, the ever-changing sequence of short-term memories. With its many illustrations and referenced sources ‘Aranzio’s Seahorse’ will be of value not only to neuroscientists, psychologists and philosophers but to all those interested in the brain and in the history of its exploration. Its relevance for a fuller understanding of Alzheimer’s disease and other disorders of memory including ‘long’ COVID is obvious.
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Hoff, Paul. On reification of mental illness: Historical and conceptual issues from Emil Kraepelin and Eugen Bleuler to DSM-5. Edited by Kenneth S. Kendler and Josef Parnas. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780198796022.003.0014.

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Reification is the assumption that mental illnesses exist independent of the observer’s conceptualization. The present debate usually addresses naturalistic reification, i.e., the definition of mental illness as an empirically detectable neurobiological dysfunction. This chapter discusses Kraepelin’s and Bleuler’s views on nosology and the position of current operationalized diagnoses (DSM-5, ICD-10), delineating recent debate on the relevance of new research technologies.There are two main conclusions: (1) “Mental illness” always refers to a concept, not to a given thing. This does not reduce the scientific value of neurobiological research: If subjective and interpersonal phenomena are acknowledged although they do not fit into a strictly naturalistic framework, sound neurobiological research will be promoted, not hampered. (2) Diagnostic and therapeutic processes in psychiatry require human interaction, so any model of mental illness must address interpersonality. Recent phenomenological concepts support this view and it seems particularly promising to reevaluate the philosophical approaches of Kant and Fichte in this respect.
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Görlitz, Anna. What can we learn from Deferred Tax Accountig? Technische Universität Dresden, 2021. http://dx.doi.org/10.25368/2022.404.

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The StuFo-Expo gives me the opportunity to make my research accessible to a broad, interdisciplinary public as part of my doctoral project. I also get the chance to get to know research topics, results and methods across disciplines. It is a unique project that connects students with one another and promotes important student skills. The topic of my research is the value relevance of deferred taxes. I am investigating the question of whether deferred taxes provide additional information for various stakeholders when predicting future corporate development. To do this, I analyze the almost 1,800 available annual financial statements of all companies listed in the DAX Prime Standard between 2007 and 2018. The poster I submitted shows that deferred taxes help forecast the development of the market value of equity up to two years in advance. Deferred tax assets as probable future tax repayments contribute positively to the company value and therefore to the market value, and deferred tax liabilities as probable future tax payments contribute negatively to the company value and therefore to the market value. I can also prove that the supplementary reporting on deferred taxes is rated negatively by market participants. Possible reasons for this are the high complexity of the information and the lack of transferability of this information to balance sheet and income statement figures. Interview studies also show that trust in deferred taxes and the associated reporting is low, as stakeholders suspect that deferred taxes are at least partially used for accounting policy.
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Saranakumar, Dr AR, Megha Ojha, Dr Malkar Vinod, and Dr D. Baskaran. Digital Innovation, Transformation and Disruption of Higher Education. SVDES BOOK SERIES, Delhi, 2022. http://dx.doi.org/10.52458/9789391842468.2022.eb.

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The theme of this book “Digital Innovation, Transformation and Disruption of Higher Education" was chosen due to its relevance in the global digitalized world. Digital transformation is the process of using digital technologies to create new — or modify existing — business processes, culture, and customer experiences to meet changing business and market requirements. This reimagining of business in the digital age is digital transformation. Digital transformation is the integration of digital technology into all areas of a business, fundamentally changing how you operate and deliver value to customers. It's also a cultural change that requires organizations to continually challenge the status quo, experiment, and get comfortable with failure. Technology has the potential to revolutionize the traditional teaching and learning process. It can eliminate the barriers to education imposed by space and time and dramatically expand access to lifelong learning. Students no longer have to meet in the same place at the same time to learn together from an instructor. Digital transformation in higher education refers to an organizational change realized by means of digital technologies and business models with the aim to improve an institution's operational performance. The book encompasses chapters with research-based perspectives in the area of digital innovations & related fields. The book can be read as a compendium of readings of digitization of higher education institutions, business and industry. We editors offer heartfelt thanks to all contributors for their valuable research incorporated in this edited book as a chapter.
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Forster, Chris. Filthy Material. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780190840860.001.0001.

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Modernist literature is inextricable from the history of obscenity. The trials of such figures as James Joyce, D. H. Lawrence, and Radclyffe Hall loom large in accounts of twentieth-century literature. Filthy Material: Modernism and the Media of Obscenity reveals the ways that debates about obscenity and literature were shaped by changes in the history of media. The emergence of film, photography, and new printing technologies shaped how “literary value” was understood, altering how obscenity was defined and which texts were considered obscene. Filthy Material rereads the history of modernist obscenity to discover the role played by technological media in debates about obscenity. The shift from the intense censorship of the early twentieth century to the effective “end of obscenity” for literature at the middle of the century was not simply a product of cultural liberalization but also of a changing media ecology. Filthy Material brings together media theory and archival research to offer a fresh account of modernist obscenity with novel readings of works of modernist literature. It sheds new light on figures at the center of modernism’s obscenity trials (such as Joyce and Lawrence), demonstrates the relevance of the discourse of obscenity to understanding figures not typically associated with obscenity debates (such as T. S. Eliot and Wyndham Lewis), and introduces new figures to our account of modernism (such as Norah James and Jack Kahane). It reveals how modernist obscenity reflected a contest over the literary in the face of new media technologies.
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SINGH, Dr ANIMESH, Dr BHAWNA CHOUDHARY, and Dr MANISHA GUPTA. TRANSFORMING BUSINESS THROUGH DIGITALIZATION. KAAV PUBLICATIONS, DELHI, INDIA, 2021. http://dx.doi.org/10.52458/9789391842390.2021.eb.

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The theme of this book “Transforming Business through Digitization‖ was chosen due to its relevance in the contemporary globalized world. The world is witnessing the pace of change of digitalization like never before the similar trend will be seen in future too. With integration of value chains and supply chains becoming a global imperative, the contribution of IT enabled services and digitalization has had great impact on Tran‘s nationalisation of businesses. The responsiveness in the value chains and in the larger supply chains will be the key to increasing the market share in future. The application of Artificial Intelligence has helped the stakeholders in value chains and supply chains in making informed & quick decisions. This has been made possible due to integrated and well organized businesses linkages leading to better storage, access and management of data. The increase digitalization and ability to track and capture data at different nodes in the value chain and supply chain will help the marketers understand the impact of various variables on the sales performance of various brands. The marketers have to work of ways to convince the stakeholders about the privacy of the data. In future there is a possibility of mixing compete data privacy with fluid artificial intelligence across the supply chain making business processes easier using the technology of block chains. The most important contribution of the digitalization in the supply chain may be seen in the area of sustainability and green initiatives. The may be made possible by the way of assessing the levels of reduction in exploitative and polluting systems and processes and making progressive modifications in those systems and processes. The book- ―transforming business through digitization‖ is an attempt to record Innovative and novel manuscripts, research-based articles, case studies, conceptual outcome-oriented business models, and practices from the innovative minds of researchers and academicians. The book encompasses twenty-four chapters with research-based perspectives in the area of e-commerce, digital governance, digital transaction platforms, business analytics, and digitalization in agriculture, digital marketing, block chain, nuero marketing, search engine marketing, UPIs, Search Engine Marketing, Digi-preneurship, and digital finance. The book can be read as a compendium of readings of digitization of business and industry.
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11

Della Porta, Donatella, Lorenzo Cini, and César Guzmán-Concha. Contesting Higher Education. Policy Press, 2020. http://dx.doi.org/10.1332/policypress/9781529208627.001.0001.

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This close investigation of student protests represents the first comparative review of the subject. Setting the wave of demonstrations within the contexts of student activism, social issues, and political movements, the book casts new light on their impact on higher education and on the broader society. The book begins with an overview of the analysis of transformation in higher education (HE) policies and student politics, linking them to research on the policy outcomes of social movements. HE policies have been shaped by various waves of student mobilization. Students have often been important actors in contentious politics, mobilizing on all main cleavages in society and often stimulating spin-off movements, as well as affecting institutional politics at large. Student protests are therefore affected by public policies at least as much as they affect them. The book focuses on these complex interactions, aiming at understanding the development of student protests within neoliberal universities. It explores four episodes of student contestation over HE reforms, which have recently taken place in Chile, Quebec, England, and Italy. In light of the findings, the book reflects on the impacts of neoliberal policies in contentious politics and point at the relevance of coalitions for a sustained impact of mobilization campaigns. The discussion also points toward the student movements' effects in terms of empowerment, the triggering of spill-over movements, and transformations in electoral and party politics. Offering sophisticated new theoretical arguments based on fascinating empirical work, the insights and conclusions revealed in this study are of value to anyone with an interest in social, political, and related studies.
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Schulkin, Jay, and Michael Power, eds. Integrating Evolutionary Biology into Medical Education. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198814153.001.0001.

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Clinicians and scientists are increasingly recognising the importance of an evolutionary perspective in studying the aetiology, prevention, and treatment of human disease; the growing prominence of genetics in medicine is further adding to the interest in evolutionary medicine. In spite of this, too few medical students or residents study evolution. This book builds a compelling case for integrating evolutionary biology into undergraduate and postgraduate medical education, as well as its intrinsic value to medicine. Chapter by chapter, the authors – experts in anthropology, biology, ecology, physiology, public health, and various disciplines of medicine – present the rationale for clinically-relevant evolutionary thinking. They achieve this within the broader context of medicine but through the focused lens of maternal and child health, with an emphasis on female reproduction and the early-life biochemical, immunological, and microbial responses influenced by evolution. The tightly woven and accessible narrative illustrates how a medical education that considers evolved traits can deepen our understanding of the complexities of the human body, variability in health, susceptibility to disease, and ultimately help guide treatment, prevention, and public health policy. However, integrating evolutionary biology into medical education continues to face several roadblocks. The medical curriculum is already replete with complex subjects and a long period of training. The addition of an evolutionary perspective to this curriculum would certainly seem daunting, and many medical educators express concern over potential controversy if evolution is introduced into the curriculum of their schools. Medical education urgently needs strategies and teaching aids to lower the barriers to incorporating evolution into medical training. In summary, this call to arms makes a strong case for incorporating evolutionary thinking early in medical training to help guide the types of critical questions physicians ask, or should be asking. It will be of relevance and use to evolutionary biologists, physicians, medical students, and biomedical research scientists.
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Halvorsen, Tor, Skare Orgeret, and Roy Krøvel. Sharing Knowledge, Transforming Societies: The Norhed Programme 2013-2020. African Minds, 2019. http://dx.doi.org/10.47622/9781928502005.

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In June 2016, the Norwegian Programme for Capacity Development in Higher Education and Research for Development (Norhed) hosted a conference on the theme of 'knowledge for development'in an attempt to shift the focus of the programme towards its academic content. This book follows up on that event. The conference highlighted the usefulness of presenting the value of Norhed's different projects to the world, showing how they improve knowledge and expand access to it through co-operation. A wish for more meta-knowledge was also expressed and this gives rise to the following questions: Is this way of co-operating contributing to the growth of independent post-colonial knowledge production in the South, based on analyses of local data and experiences in ways that are relevant to our shared future? Does the growth of academic independence, as well as greater equality, and the ability to develop theories different to those imposed by the better-off parts of the world, give rise to deeper understandings and better explanations? Does it, at least, spread the ability to translate existing methodologies in ways that add meaning to observations of local context and data, and thus enhance the relevance and influence of the academic profession locally and internationally? This book, in its varied contributions, does not provide definite answers to these questions but it does show that Norhed is a step in the right direction. Norhed is an attempt to fund collaboration within and between higher education institutions. We know that both the uniqueness of this programme, and ideas of how to better utilise the learning and experience emerging from it, call for more elaboration and broader dissemination before we can offer further guidance on how to do things better. This book is a first attempt.
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14

Pope, Elizabeth M., Catarina Brandão, and Cedric C. Sanders. Scientific Congresses: What is Our Future? Ludomedia, 2022. http://dx.doi.org/10.36367/ntqr.11.2022.editorial.

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As we write these words, the COVID-19 pandemic has become part of our lives in a much more controlled way. For instance, some of our habits have changed and we are able to resume our activities in the way of a “new normal,” returning to social contact with family, friends, and colleagues. In returning to a life without the constraint of the virus at such a high level, the academy tries to resume its rituals, including scholarly events. Email boxes and physical boards at universities are once again filling up with calls for submission of abstracts for congresses, seminars, and workshops. As these events are happening again, academia seems to be reflecting on the pros and cons of onsite scientific events. While acknowledging the importance of such scientific events and their potential for strengthening scholarly communities and collaborations, many academics have begun questioning the real impact of being physically present. This questioning seems to be based on several factors. On the one hand, it is clear that universities have been increasingly devaluing academics’ presence in congresses (unless by invitation). They allocate less funding for these activities, especially for those academics who wish to attend an event without presentation. With no presentation, institutions devalue attendance in performance appraisal processes. Increasingly, academic institutions value publications (indexed, despite some positive movement seeking to counter the tyranny of the “publish or perish” motto), and an academics ability to raise funding. Yet, not all congresses are associated with publication processes in indexed journals or proceedings. Books of abstracts (once edited by any congress) are almost extinct, namely because of their devaluation by institutes of higher learning (and funding entities). On the other hand, the massive and necessary use of online scientific events in 2020 and 2021 allowed us to realize that it is possible, efficient, and effective to hold these events in a format different from the traditional one. The internet offers versatility and more and more congresses are now offered online or in hybrid formats. These formats allow academics to overcome financial and physical complications caused by in-person scholarly events. Academics can request less funding and, at the same time, mitigate concerns of acceptance without presentations, covering classes while away, or having to supplement university sponsorship with personal funds. At some universities, funding comes after attendance regardless of availability of those funds and academics are asked to pay registration fee, plane tickets, and lodging with the expectation of being reimbursed upon return. This is particularly challenging given the present economic situation around the globe. At the same time, while physically at the event and away from families, work continues to accumulate for academics. They then must wade through this excess upon returning home, adding to an already excessive workload. This makes maintaining a work-life balance challenging. We at New Trends in Qualitative Research (NTQR) believe it is particularly relevant to discuss this topic within the context of the release of NTQR Volume 11. NTQR is an indexed journal associated with international scientific events in the field of qualitative research - Congreso Ibero-Americano en Investigación Cualitativa (CIAIQ) and the World Conference on Qualitative Research (WCQR). Specifically, the volume that we edit here aggregates works that, having been originally presented at WCQR2022 (held in an online format), went through a double-blind review process. This volume, annually edited (as WCQR is an annual event), allows us, as editors, to condense a diverse set of qualitative research work, focusing on different topics, and with different methodological designs. And, our concern as editors has always been to assure the quality of the published works, namely through a careful review and editing process. We do not know if we are ready to give up our physical presence at scientific events. But, with opportunities such as online presentations and online publishing venues, we may now be much more judicious in this presence. We may now take time to ponder the relevance of investing in attending a scientific event, and selecting (hand-drawn) two or three events per year, at most. WCQR has a strong emphasis in the building of a scientific community (in this case, bonded by the interest in qualitative research), reconciling physical and online presence, and is associated with quality journals. These aspects help academics to select it as one of the events where it is important to be present. Sincerely, The Editors
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15

Zydroń, Tymoteusz. Wpływ systemów korzeniowych wybranych gatunków drzew na przyrost wytrzymałości gruntu na ścinanie. Publishing House of the University of Agriculture in Krakow, 2019. http://dx.doi.org/10.15576/978-83-66602-46-5.

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The aim of the paper was to determine the influence of root systems of chosen tree species found in the Polish Flysch Carpathians on the increase of soil shear strength (root cohesion) in terms of slope stability. The paper's goal was achieved through comprehensive tests on root systems of eight relatively common in the Polish Flysch Carpathians tree species. The tests that were carried out included field work, laboratory work and analytical calculations. As part of the field work, the root area ratio (A IA) of the roots was determined using the method of profiling the walls of the trench at a distance of about 1.0 m from the tree trunk. The width of the. trenches was about 1.0 m, and their depth depended on the ground conditions and ranged from 0.6 to 1.0 m below the ground level. After preparing the walls of the trench, the profile was divided into vertical layers with a height of 0.1 m, within which root diameters were measured. Roots with diameters from 1 to 10 mm were taken into consideration in root area ratio calculations in accordance with the generally accepted methodology for this type of tests. These measurements were made in Biegnik (silver fir), Ropica Polska (silver birch, black locust) and Szymbark (silver birch, European beech, European hornbeam, silver fir, sycamore maple, Scots pine, European spruce) located near Gorlice (The Low Beskids) in areas with unplanned forest management. In case of each tested tree species the samples of roots were taken, transported to the laboratory and then saturated with water for at least one day. Before testing the samples were obtained from the water and stretched in a. tensile testing machine in order to determine their tensile strength and flexibility. In general, over 2200 root samples were tested. The results of tests on root area ratio of root systems and their tensile strength were used to determine the value of increase in shear strength of the soils, called root cohesion. To this purpose a classic Wu-Waldron calculation model was used as well as two types of bundle models, the so called static model (Fiber Bundle Model — FIRM, FBM2, FBM3) and the deformation model (Root Bundle Model— RBM1, RBM2, mRBM1) that differ in terms of the assumptions concerning the way the tensile force is distributed to the roots as well as the range of parameters taken into account during calculations. The stability analysis of 8 landslides in forest areas of Cicikowicleie and Wignickie Foothills was a form of verification of relevance of the obtained calculation results. The results of tests on root area ratio in the profile showed that, as expected, the number of roots in the soil profile and their ApIA values are very variable. It was shown that the values of the root area ratio of the tested tree species with a diameter 1-10 ram are a maximum of 0.8% close to the surface of the ground and they decrease along with the depth reaching the values at least one order of magnitude lower than close to the surface at the depth 0.5-1.0 m below the ground level. Average values of the root area ratio within the soil profile were from 0.05 to 0.13% adequately for Scots pine and European beech. The measured values of the root area ratio are relatively low in relation to the values of this parameter given in literature, which is probably connected with great cohesiveness of the soils and the fact that there were a lot of rock fragments in the soil, where the tests were carried out. Calculation results of the Gale-Grigal function indicate that a distribution of roots in the soil profile is similar for the tested species, apart from the silver fir from Bie§nik and European hornbeam. Considering the number of roots, their distribution in the soil profile and the root area ratio it appears that — considering slope stability — the root systems of European beech and black locust are the most optimal, which coincides with tests results given in literature. The results of tensile strength tests showed that the roots of the tested tree species have different tensile strength. The roots of European beech and European hornbeam had high tensile strength, whereas the roots of conifers and silver birch in deciduous trees — low. The analysis of test results also showed that the roots of the studied tree species are characterized by high variability of mechanical properties. The values Of shear strength increase are mainly related to the number and size (diameter) of the roots in the soil profile as well as their tensile strength and pullout resistance, although they can also result from the used calculation method (calculation model). The tests showed that the distribution of roots in the soil and their tensile strength are characterized by large variability, which allows the conclusion that using typical geotechnical calculations, which take into consideration the role of root systems is exposed to a high risk of overestimating their influence on the soil reinforcement. hence, while determining or assuming the increase in shear strength of soil reinforced with roots (root cohesion) for design calculations, a conservative (careful) approach that includes the most unfavourable values of this parameter should be used. Tests showed that the values of shear strength increase of the soil reinforced with roots calculated using Wu-Waldron model in extreme cases are three times higher than the values calculated using bundle models. In general, the most conservative calculation results of the shear strength increase were obtained using deformation bundle models: RBM2 (RBMw) or mRBM1. RBM2 model considers the variability of strength characteristics of soils described by Weibull survival function and in most cases gives the lowest values of the shear strength increase, which usually constitute 50% of the values of shear strength increase determined using classic Wu-Waldron model. Whereas the second model (mRBM1.) considers averaged values of roots strength parameters as well as the possibility that two main mechanism of destruction of a root bundle - rupture and pulling out - can occur at the same. time. The values of shear strength increase calculated using this model were the lowest in case of beech and hornbeam roots, which had high tensile strength. It indicates that in the surface part of the profile (down to 0.2 m below the ground level), primarily in case of deciduous trees, the main mechanism of failure of the root bundle will be pulling out. However, this model requires the knowledge of a much greater number of geometrical parameters of roots and geotechnical parameters of soil, and additionally it is very sensitive to input data. Therefore, it seems practical to use the RBM2 model to assess the influence of roots on the soil shear strength increase, and in order to obtain safe results of calculations in the surface part of the profile, the Weibull shape coefficient equal to 1.0 can be assumed. On the other hand, the Wu-Waldron model can be used for the initial assessment of the shear strength increase of soil reinforced with roots in the situation, where the deformation properties of the root system and its interaction with the soil are not considered, although the values of the shear strength increase calculated using this model should be corrected and reduced by half. Test results indicate that in terms of slope stability the root systems of beech and hornbeam have the most favourable properties - their maximum effect of soil reinforcement in the profile to the depth of 0.5 m does not usually exceed 30 kPa, and to the depth of 1 m - 20 kPa. The root systems of conifers have the least impact on the slope reinforcement, usually increasing the soil shear strength by less than 5 kPa. These values coincide to a large extent with the range of shear strength increase obtained from the direct shear test as well as results of stability analysis given in literature and carried out as part of this work. The analysis of the literature indicates that the methods of measuring tree's root systems as well as their interpretation are very different, which often limits the possibilities of comparing test results. This indicates the need to systematize this type of tests and for this purpose a root distribution model (RDM) can be used, which can be integrated with any deformation bundle model (RBM). A combination of these two calculation models allows the range of soil reinforcement around trees to be determined and this information might be used in practice, while planning bioengineering procedures in areas exposed to surface mass movements. The functionality of this solution can be increased by considering the dynamics of plant develop¬ment in the calculations. This, however, requires conducting this type of research in order to obtain more data.
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