872 research outputs found
Geomorphological connectivity and sensitivity examined in a recently degraded gravel-bed stream: implications for river-floodplain rehabilitation
The study of river complexity and sensitivity to future human land-use activities and climate change is a fast growing field within the discipline of fluvial geomorphology. Associated with this is a need to improve river rehabilitation and catchment management approach, design and effectiveness. This study aimed to investigate drivers of the recent geomorphological sensitivity of the Baviaanskloof River-floodplain, an upland system in South Africa, by integrating the concepts of geomorphological connectivity and Panarchy. The understanding generated was used to evaluate the approach of the State agency, Working for Wetlands (WfWet), to river-floodplain rehabilitation in the catchment.The concepts of geomorphological connectivity and Panarchy provide useful frameworks for understanding interactions between geomorphological processes and structure across scales of space and time. Geomorphological connectivity explains the degree to which water and sediment is linked in a river landscape, determined by the distribution of erosional and depositional landforms (Brierley et al. 2006; Fryirs et al. 2007a; Fryirs et al. 2007b). Panarchy attempts to explain lagged response to disturbances, non-linear interactions, and sudden shifts in system state, and has been applied largely to ecological systems. Panarchy theory, when combined with the concept of geomorphological connectivity, provides a guiding framework for understanding river complexity in greater depth. The first results chapter of this study investigated river long-term and recent geomorphological history, towards understanding the nature and timing of river geomorphological cycling between erosion and deposition. Optically Stimulated Luminescence dating of alluvial fan and floodplain sedimentary units was conducted, for analysis of river-floodplain long-term history (100s to 1 000s of years). Interviews with 11 local landowners, combined with analysis of historic aerial imagery and river-floodplain topographic surveys, provided a means of describing recent (last few decades) geomorphological dynamics. The results indicated that the Baviaanskloof is naturally a cut- and-fill landscape over scales of several hundred to thousands of years, characterized by the alternation between phases of high fluvial energy and alluvial fan expansion, and low energy conditions associated with floodplain accretion. Recent and widespread river-floodplain degradation was compressed into a short period of approximately 30 years, suggesting that one or more drivers have pushed the system beyond a threshold, resulting in increased water and sediment connectivity. The second results chapter investigated the role of human land-use activities and flooding frequency and magnitude, as drivers of recent river-floodplain degradation. Human impacts were investigated by describing land-use activities for the preceding 80 years, and relating these activities to changes in river-floodplain form and behavior. Temporal trends in flood events of different frequency and magnitude were investigated by analyzing rainfall data, integrated with landowner reports of flood-inducing rainfall magnitudes. The findings indicated that human land-use activities have been an important driver of recent river- floodplain degradation, through the enhancement of water and sediment connectivity across spatial scales of the catchment. Episodic and high magnitude floods synergized with human driven increased connectivity, precipitating stream power and geomorphological threshold breaches, resulting in a shift in river behaviour. The third results chapter investigated the influence of tributary-junction streams and fans on the geomorphological form, behavior and sensitivity of the Baviaanskloof River. Local- scale topographic impacts of tributary fans and streams were described using topographic surveys and geomorphological mapping techniques. Tributary streams form a major control on the behaviour of the river, by influencing the degree of coarse sediment connectivity with the main channel. Although tributary fans buffer the river from disturbances occurring in the wider catchment, they initiate topographic variations along the floodplain, influencing local-scale patterns of deposition and erosion along the river. The main river responds to water and sediment inputs from tributary junction streams by locally adjusting longitudinal slope, maintaining an overall constant slope of 0.0066 m/m. The response of the Baviaanskloof River to tributary junction fans and streams is however variable, and is fashioned by complex interactions between geomorphological and anthropogenic factors. The final two chapters of the thesis evaluate the findings of the study within the context of river-floodplain rehabilitation approaches in South Africa, and within the theoretical, philosophical and methodological context of the research. The first of these two chapters evaluates the approach of the WfWet programme to river-floodplain rehabilitation in the Baviaanskloof. The chapter indicates that the present practice of WfWet is to reinstate a pre-degradation state, which is not suited to the Baviaanskloof River-floodplain, since the river-floodplain has passed a geomorphological threshold, resulting in a new set of interacting processes and landforms. The author presents a conceptual model illustrating the existence of geomorphological adaptive cycles interacting across spatial and temporal scales, thereby attempting to explain a river Panarchy specific to the Baviaanskloof. From this conceptual model, a hierarchical rehabilitation framework, targeting geomorphological processes and structure situated at different spatial and temporal scales of the landscape is suggested. The final chapter discusses the implications of integrating the concepts of geomorphological connectivity and river Panarchy theory in studies of river complexity and sensitivity to geomorphological change. The author suggests that there is scope for further investigation of the application of the two concepts within the discipline of fluvial geomorphology, particularly with regard to developing quantitative approaches to measuring and describing connectivity and Panarchy
Writing to and Beyond the Test: The Writing Habitus of the First Standards-based Curriculum Cohort
Investigative interviewers\u27 perceptions of their difficulty in adhering to open-ended questions with child witnesses
Best practice guidelines for conducting investigative interviews of children emphasise the importance of obtaining free narrative accounts with the use of open-ended questions. However, research indicates that most investigative interviewers underutilise open-ended questions, even following intensive training in their use. The aim of the current study was to explore investigative interviewers\u27 perceptions of their difficulty in asking open-ended questions. During a training course on how to use open-ended questions, eight child abuse investigators were individually interviewed about why they had asked specific questions in a 10-minute mock interview conducted immediately earlier with a school child. Overall, three reasons were identified. These related to: 1. the specificity of the information required from children; 2. the unfamiliar nature of the open-ended discourse style; and 3. the complex distinction between open-ended versus specific questions. Each of these themes is discussed, along with the implications for trainers and researchers in child investigative interviewing.<br /
What makes a good investigative interviewer of children? A comparison of police officers\u27 and experts; perceptions
Purpose – The purpose of this paper is to examine police officers’ perceptions about their role in interviewing children, and to compare these perceptions with those of child eyewitness memory experts.Design/methodology/approach – A diverse sample of 23 police officers (from three states of Australia) individually participated in in-depth interviews where they were asked to define what makes a good interviewer in the area of child abuse investigation.Findings – Irrespective of the background of the officers, the important role of interviewers’ personal attributes was emphasised (e.g. having a relaxed, empathetic, warm nature). Such personal attributes were more prominent in the participants’ descriptions than knowledge of legislation and children’sdevelopment, prior job experience, and interviewing techniques.Research limitations/implications – The paper shows that while child eyewitness memory experts acknowledge the importance of establishing a bond of mutual trust between the interviewer and the child, the importance of utilising an open-ended questioning style for enhancing rapport, andfor eliciting a detailed and accurate account of abuse cannot be overstated. The possible reasons for the police officers’ emphasis on personal qualities are discussed.Originality/value – This paper has revealed that limitations in the competency of police officers in interviewing children is not merely a problem of “doing” (i.e. learning to ask open-ended questions),but may also reflect ingrained attitudinal and organisational barriers.<br /
Professionals\u27 perceptions of a new model of sexual assault investigation adopted by Victoria Police
This article presents a qualitative evaluation of a new method of operation for sexual assault investigation developed by Victoria Police. The model is characterised by two core components: the establishment of specialist teams of investigators responsible for investigation and victim support; and the establishment of service sites, referred to as \u27Multidisciplinary Centres\u27, where all key services are located in a single building separate from police stations. The research approach consisted of in-depth interviews with 90 stakeholders (police, counsellors, medical officers, child protection workers and prosecutors). Collectively, these interviews revealed strong, unanimous support for the ideologies that underpinned the new reforms. Reported outcomes included the following: improved collaboration; increased victim satisfaction, referrals between professionals and reporting rates; reduced response and investigation times; better quality briefs; and higher prosecution and conviction rates. These findings, along with the stakeholders\u27 suggestions for further improvements, are discussed
Mutiny in Côte d'Ivoire
Since 1990, Côte d’Ivoire has experienced over a dozen army mutinies, with three major events occurring in the first half of 2017. This paper explores the underlying causes of these events, considering both this year’s mutinies and the state’s prior experiences with military insubordination. A review of the events of Côte d’Ivoire’s tumultuous 2017 indicates a number of parallels with some of its earlier mutinies, though these more recent events are perhaps unique due to the presence of a larger range of dynamics and the scale of the mutineers’ demands. Beyond requests for better pay, which are nearly ubiquitous, these events also illustrate the general hazards of post-conflict civil–military relations, including challenges related to demobilisation, integration of rebel forces, the consequences of soldiers having contributed to a leader’s ascendance, and the perils of soldier loyalties lying with personalities instead of the state.Seit 1990 kam es in Côte d’Ivoire zu mehr als einem Dutzend Fällen von Aufruhr in der Armee; drei bedeutendere Einzelereignisse waren in der ersten Hälfte des Jahres 2017 zu verzeichnen. Die Autoren des Beitrags untersuchen die Hintergründe, indem sie sowohl das Geschehen im ersten Halbjahr 2017 betrachten als auch frühere Erfahrungen des Staates mit Gehorsamsverweigerung von Militärs. Die Analyse der Ereignisse in Côte d’Ivoire im bislang turbulenten Jahr 2017 offenbart Parallelen zu früheren Meutereien, auch wenn die jüngsten Fälle wohl einzigartig sind, was die Breite der Dynamik und die Größenordnung der Forderungen angeht. Abgesehen von den fast immer vorgetragenen Forderungen nach besserer Bezahlung offenbaren die jüngsten Meutereien auch die generellen Gefahren für die zivil-militärischen Beziehungen in Nachkonfliktgesellschaften, wie die Herausforderungen der Demobilisierung und der Integration bewaffneter Rebellen und die Risiken, die sich ergeben, wenn Soldaten zum Aufstieg von Führungspersönlichkeiten beigetragen haben beziehungsweise wenn die Loyalität von Soldaten Einzelpersonen gilt und nicht dem Staat
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Number of Pages: 10Integrative BiologyGeological Science
Brine Shrimp Lab
Young brine shrimp movements within a petri dish are tracked by students. Students are challenged to determine and verify whether the brine shrimp move in a random walk. From this exercise students gain greater understanding of PDE models, diffusion and parameter estimation.https://digitalcommons.usu.edu/lemb/1001/thumbnail.jp
‘Being an academic is not a 9–5 job’: long working hours and the ‘ideal worker’ in UK academia
The deregulation of working time has been occurring over recent decades. Academia is one of the many industries that can be characterised by a long hours work culture and intensification of work. This is significant given the negative effects of such a work culture on the physical and mental health and well-being of workers. Using evidence from two UK-based qualitative studies, this paper begins to explore the causes and effects of academic long hours work culture further. It has a particular focus on the extent to which the long hours culture is a result of cultural and structural changes in higher education, which have led to an increased focus on performance and outcome measures. It queries whether this is also shaped by more personal factors, such as the desire to excel and blurred boundaries between work and leisure, whereby the pursuit of knowledge may be a source of leisure for academics. It finds that while individual factors contribute to the long hours culture, these factors are shaped by cultural norms and pressures to cultivate a perception of the ‘ideal academic’ within an increasingly target-driven and neoliberal environment
Contrasting the perceptions of child testimony experts, prosecutors and police officers regarding individual child abuse interviews
The aim of this study was to compare and contrast the perceptions of various stakeholders regarding a series of interviews about child abuse. Eight focus groups were conducted, each involving a police officer (child abuse investigator), a prosecutor who specializes in child abuse and a child testimony expert. The aim of the focus groups was to discuss the strengths and weaknesses of the specific interviews, which were conducted by the police officer in each focus group. Thematic analysis showed that the prosecutors and child testimony experts were relatively consistent in their perceptions about the need for more free narrative from child witnesses, and to ensure that police officers demonstrate open-mindedness when interviewing children. Differences in priorities and assumptions about the value of various interview techniques, however, were found among the stakeholders. These differences and their practical implications are discussed.<br /
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