Reviews

Successful Instructional Diagrams by Ric Lowe, London, Kogan Page, 1993. ISBN: 0–7494–0711–5

Resilience of New Zealand indigenous forest fragments to impacts of livestock and pest mammals

A number of factors have combined to diminish ecosystem integrity in New Zealand indigenous lowland forest fragments surrounded by intensively grazed pasture. Livestock grazing, mammalian pests, adventive weeds and altered nutrient input regimes are important drivers compounding the changes in fragment structure and function due to historical deforestation and fragmentation. We used qualitative systems modelling and empirical data from Beilschmiedia tawa dominated lowland forest fragments in the Waikato Region to explore the relevance of two common resilience paradigms – engineering resilience and ecological resilience – for addressing the conservation management of forest fragments into the future. Grazing by livestock and foraging/predation by introduced mammalian pests both have direct detrimental impacts on key structural and functional attributes of forest fragments. Release from these perturbations through fencing and pest control leads to partial or full recovery of some key indicators (i.e. increased indigenous plant regeneration and cover, increased invertebrate populations and litter mass, decreased soil fertility and increased nesting success) relative to levels seen in larger forest systems over a range of timescales. These changes indicate that forest fragments do show resilience consistent with adopting an engineering resilience paradigm for conservation management, in the landscape context studied. The relevance of the ecological resilience paradigm in these ecosystems is obscured by limited data. We characterise forest fragment dynamics in terms of changes in indigenous species occupancy and functional dominance, and present a conceptual model for the management of forest fragment ecosystems

Investigating possible retinal biomarkers of head trauma in Olympic boxers using optical coherence tomography (OCT)

Purpose: Changes to retina have been reported after a number of neurodegenerative conditions. The purpose of this study was to investigate retinal structures in Olympic boxers exposed to frequent head blows. Methods:Retinal imaging offers potential as a non-invasive biomarkers of neuropathology. Macula and retinal nerve fibre layer (RNFL) thickness was measured using optical coherence tomography (OCT) in UK Olympic boxers attending two mandatory eye screening programs, 18 months apart. Data from the two eye-screenings provide longitudinal data of retinal change over time. Sedentary healthy subjects (controls) without past or present history of concussion were also screened at the time of the second boxer screening to provide comparison cross-sectional data. Results: Sixteen Olympic boxers aged 20-33 years and 20 sedentary healthy controls, aged 24-45 years were recruited. Significant macula thickening was observed over time (18 months) in 75% of right and 50% of left eye sectors. For RNFL, left eye quadrants thickened. For right eye RNFL quadrants, thickening and thinning of this layer was observed. Cross-sectional results showed thinner macula sectors and RNFL quadrants in Olympic boxers compared to controls. Conclusion: Significant change to macula and RNFL densities, occurring over an 18 month interval is an unexpected finding in otherwise heathy elite sportsmen. In addition, macula and RNFL were thinner than healthy sedentary controls. OCT may prove clinically useful as a candidate retinal biomarker of neuropathological change after mild traumatic brain injury and/or repeat head blows

Probing Software Engineering Beliefs about System Testing Defects: Analyzing Data for Future Directions

Research findings are often expressed as short startling sentences or software engineering (SE) beliefs such as “about 80 percent of the defects come from 20 percent of the modules” and “peer reviews catch 60 percent of the defects” [2]. Such SE beliefs are particularly important in industry, as they are attention-getting, easily understandable, and thus practically useful. In this paper we examine the power of such SE beliefs to justify process improvement through empirical validation of selected beliefs related to the increase or decrease of defects in system testing. We explore four basic SE beliefs in data from two midsize embedded software development organizations in Japan, and based on this information, identify possible process improvement actions for each organization. Based on our study, even small and medium-sized enterprises (SMEs) can use this approach to find possible directions to improve their process, which will result in better products

Integrating Humanitarian Mine Action and Humanitarian Forensic Action

Humanitarian mine action (HMA) and humanitarian forensic action (HFA) have had a global impact in recent decades. However, these two areas could work more closely together in view of some of the contexts in which they operate. Often when HMA operators clear explosive ordnance (EO) after conflict, they find human remains, especially in urban areas. When human remains are encountered, operators have responsibilities to ensure that they are dealt with appropriately. When both HMA and HFA actors are present, there is a need for an increased awareness and understanding of each other’s role. Human remains should be returned to families without disruption or compromising humanitarian principles wherever possible and any relevant evidence assisting identification should be recovered. Similarly, when forensic scientists work to recover human remains, they may encounter explosive devices. When HFA operations encounter mines, improvised explosive devices (IEDs), or explosive remnants of war (ERW) they should also actively enable HMA support. This article examines the extent of the cooperation to date and identifies ways in which it can be improved. Recommendations and practical measures are provided to encourage a higher degree of collaboration going forward

Scaling beta-lactam antimicrobial pharmacokinetics from early life to old age

AIMS Beta-lactam dose optimization in critical care is a current priority. We aimed to review the pharmacokinetics (PK) of three commonly used beta-lactams (amoxicillin ± clavulanate, piperacillin-tazobactam and meropenem) to compare PK parameters reported in critically and noncritically ill neonates, children and adults, and to investigate whether allometric and maturation scaling principles could be applied to describe changes in PK parameters through life. METHODS A systematic review of PK studies of the three drugs was undertaken using MEDLINE and EMBASE. PK parameters and summary statistics were extracted and scaled using allometric principles to 70 kg individual for comparison. Pooled data were used to model clearance maturation and decline using a sigmoidal (Hill) function. RESULTS A total of 130 papers were identified. Age ranged from 29 weeks to 82 years and weight from 0.9-200 kg. PK parameters from critically ill populations were reported with wider confidence intervals than those in healthy volunteers, indicating greater PK variability in critical illness. The standard allometric size and sigmoidal maturation model adequately described increasing clearance in neonates, and a sigmoidal model was also used to describe decline in older age. Adult weight-adjusted clearance was achieved at approximately 2 years postmenstrual age. Changes in volume of distribution were well described by the standard allometric model, although amoxicillin data suggested a relatively higher volume of distribution in neonates. CONCLUSIONS Critical illness is associated with greater PK variability than in healthy volunteers. The maturation models presented will be useful for optimizing beta-lactam dosing, although a prospective, age-inclusive study is warranted for external validation