Application of high speed filming techniques to the study of rearwards melt ejection in laser drilling

Melt ejection is the dominant material removal mechanism in long, ms, pulse laser drilling of metals, a process with applications such as the drilling of cooling holes in turbine blades. Droplets of molten material are ejected through the entrance hole and, after breakthrough, through the exit hole. High speed filming is used to study the ejected material in order to better understand how this debris may interact with material in the immediate vicinity of the drilled hole. Existing studies have quantified various aspects of melt ejection, however they usually focus on ejection through the entrance hole. This work concentrates on rear melt ejection and is relevant to issues such as rear wall impingement. A 2kW IPG 200S fibre laser is used to drill mild steel. High speed filming is combined with image analysis to characterise the rearward-ejected material. Particle size and velocity data is presented as a function of drilling parameters. It is concluded that high speed filming combined with image analysis and proper consideration of process limitations and optimisation strategies can be a powerful tool in understanding resultant debris distributions

No Fault Found: The Root Cause

No Trouble Found (NTF) has been discussed for several years [1]. An NTF occurs when a device fails at the board/system level and that failure cannot be confirm by the component supplier. There are several explanations for why NTFs occur, including: device complexity; inability to create system level hardware/software transactions which uncover hard to find defects; different environments during testing (power, thermal, noise). More recently a new concept, No Fault Found (NFF), has emerged. A NFF represents a defect which cannot be detected by any known means so far. The premise is that at some point the defect will be exposed - most likely at a customer site when the device is in a system. Given that we looking for a defect that we know nothing about and are theoretically undetectable it will be interesting to see what the panel has to say about the nature of these defects and how we intend to find them

Making sense of a mess: “doing” resilience in the vortex of a crisis

Purpose The purpose of the paper is to investigate how human resource professionals (HRPs), in a variety of organizations, responded to the crisis brought about by the event of COVID-19. In particular, it aims to show how organizations, across all sectors, in Western Australia responded with urgency and flexibility to the crisis and showed “resilience in practice”. Design/methodology/approach The study is based on 136 questionnaire responses, 32 interviews and 25 managerial narratives. The mixed qualitative methodology was designed to enable an investigation of the impact of COVID-19 and the response of HRPs. Findings HRPs have responded with agility and flexibility to the impact of COVID-19. They have done so through extensive trial and error, sometimes succeeding, sometimes failing. They have not simply activated a preconceived continuity plan. Research limitations/implications The research indicates that resilience is an ongoing accomplishment of organizations and the people in them. The objective was description rather than prescription, and the research does not offer solutions to future pandemic-like situations. Practical implications The research suggests that, given the impact of COVID-19 on organizations, HR practices, processes and policies will need to be thoroughly reconsidered for relevance in the post-COVID world. Possible future directions are highlighted. Originality/value The research considers the actions of HRPs as they responded to a global crisis as the crisis unfolded

Prospective associations of low muscle mass and strength with health-related quality of life over 10-year in community-dwelling older adults

Aims: This study aims to describe the associations of low muscle mass, handgrip (HGS) and lower-limb muscle strength (LMS) with health-related quality of life (HRQoL) over 10 years in community-dwelling older adults.Methods: Participants (N = 1002; 51% women; mean age 63 ± 7.4 years) were prospectively followed for 10 years. HRQoL was measured using the validated assessment of quality of life (AQoL) instrument. Appendicular lean mass (ALM) was assessed using dual energy X-ray absorptiometry and normalized to body mass index (BMI). HGS and LMS were assessed using dynamometers. Low ALM/BMI (ALM/BMILOW), LMS (LMSLOW) and HGS (HGSLOW) at baseline were defined as the lowest 20% of the sex-specific distribution for each measure. Linear mixed effect regression models, adjusting for confounders, were used to estimate the association between ALM/BMILOW, LMSLOW, and HGSLOW at baseline and HRQoL over 10 years.Results: Participants with LMSLOW (β = -0.061, 95% CI: -0.089, -0.033) and women (β = -0.089, 95% CI: -0.129, -0.049) but not men (β = -0.023, 95% CI: -0.064, 0.019) with HGSLOW had clinically meaningful reductions in HRQoL over 10 years compared to those with normal strength. There was a weaker but statistically significant association between ALM/BMILOW and 10-year HRQoL (β = -0.038, 95% CI: -0.068, -0.008).Conclusions: Lower-limb muscle strength and handgrip strength (in women only), which can be easily measured in clinical practice, appear more important than muscle mass for HRQoL

The impact of Covid-19 on human resource management: avoiding generalisations

Many organisations are using remote working for the first time. HR professionals are having to improvise daily, write Eileen Aitken-Fox, Jane Coffey, Kantha Dayaram, Scott Fitzgerald, Chahat Gupta, Steve McKenna, and Amy Wei Tia

Light physical activity is positively associated with cognitive performance in older community dwelling adults.

OBJECTIVES: To evaluate the associations between an objective measure of different intensities of physical activity, upper- and lower-limb muscle strength and psychomotor performance and set-shifting domains of cognitive executive function in older adults. DESIGN: A cross-sectional study. METHODS: From the Tasmanian Older Adult Cohort Study, 188 community-dwelling older adults (53.7% female; mean age±SD 63.98±7.3 years) undertook 7-day physical activity behaviour monitoring using an accelerometer. Dynamometers were used to assess leg extension strength. The Trail Maker Tests were used to measure psychomotor processing speed and set-shifting performance. RESULTS: When controlling for age, smoking history, alcohol intake, educational achievement and neuropsychological functioning, higher levels of light physical activity, but not sedentary behaviour or moderate or vigorous physical activity, was found to be associated with better set-shifting performance. Neither physical activity behaviour or muscle strength were found to be associated with psychomotor performance. In addition, older age, greater alcohol intake, and lower levels of educational attainment, verbal learning and memory performance were significantly associated with lower scores on the set-shifting task; whereas older age and reduced neuropsychological functioning were associated with lower psychomotor processing speed scores. CONCLUSIONS: Light physical activity is associated with higher executive functioning in community-dwelling older adults and this strengthens the evidence supporting exercise as a neuroprotective agent. Further studies are needed to understand why light physical activity behaviour positively influences executive functioning, and how such physical activity can be implemented into the daily routine of older adults

Co-incorporation of biodegradable wastes with crop residues to reduce nitrate pollution of groundwater and decrease waste disposal to landfill

Return of high nitrogen (N) content crop residues to soil, particularly in autumn, can result in environmental pollution resulting from gaseous and leaching losses of N. The EU Landfill Directive will require significant reductions in the amounts of biodegradable materials going to landfill. A field experiment was set up to examine the potential of using biodegradable waste materials to manipulate losses of N from high N crop residues in the soil. Leafy residues of sugar beet were co-incorporated into soil with materials of varying C:N ratios, including molasses, compactor waste, paper waste, green waste compost and cereal straw. The amendment materials were each incorporated to provide approximately 3.7 t C per hectare. The most effective material for reducing nitrous oxide (N2O) production and leaching loss of NO3− was compactor waste, which is the final product from the recycling of cardboard. Adding molasses increased N2O and NO3− leaching losses. Six months following incorporation of residues, the double rate application of compactor waste decreased soil mineral N by 36 kg N per hectare, and the molasses increased soil mineral N by 47 kg N per hectare. Compactor waste reduced spring barley grain yield by 73% in the first of years following incorporation, with smaller losses at the second harvest. At the first harvest, molasses and paper waste increased yields of spring barley by 20 and 10% compared with sugar beet residues alone, and the enhanced yield persisted to the second harvest. The amounts of soil mineral N in the spring and subsequent yields of a first cereal crop were significantly correlated to the lignin and cellulose contents of the amendment materials. Yield was reduced by 0.3–0.4 t/ha for every 100 mg/g increase in cellulose or lignin content. In a second year, cereal yield was still reduced and related to the cellulose content of the amendment materials but with one quarter of the effect. Additional fertilizer applied to this second crop did not relieve this effect. Although amendment materials were promising as tools to reduce N losses, further work is needed to reduce the negative effects on subsequent crops which was not removed by applying 60 kg/ha of fertilizer N

Adam Smith Revisited: Moral Leadership for Global Recovery and Restoration

OUR WORLD IN TURMOIL AND TRANSITION “As our own species is in the process of proving, one cannot have superior science and inferior morals. The combination is unstable and self-destroying” Arthur C. Clarke (1965). The 2020’s have already revealed exceptional and pervasive interruptions to business and life as usual. From Covid-19 to bio-diversity collapse and climate change, many species, including our own, require unprecedented responses to the existential threats prematurely killing us, nature and livelihoods. Commentators expect the way we see our future on the planet to have permanently changed. Most are grappling with what this will or should be like and who might take us on the journey there, whilst we also have the emergence of AI, hacking of the brain and emotions, quantum computing, and the accompanying rise of ‘educated’ machines and devices

Preserving the palaeoenvironmental record in Drylands: Bioturbation and its significance for luminescence-derived chronologies

Luminescence (OSL) dating has revolutionised the understanding of Late Pleistocene dryland activity. However, one of the key assumptions for this sort of palaeoenvironmental work is that sedimentary sequences have been preserved intact, enabling their use as proxy indicators of past changes. This relies on stabilisation or burial soon after deposition and a mechanism to prevent any subsequent re-mobilisation. As well as a dating technique OSL, especially at the single grain level, can be used to gain an insight into post-depositional processes that may distort or invalidate the palaeoenvironmental record of geological sediment sequences. This paper explores the possible impact of bioturbation (the movement of sediment by flora and fauna) on luminescence derived chronologies from Quaternary sedimentary deposits in Texas and Florida (USA) which have both independent radiocarbon chronologies and archaeological evidence. These sites clearly illustrate the ability of bioturbation to rejuvenate ancient weathered sandy bedrock and/or to alter depositional stratigraphies through the processes of exhumation and sub-surface mixing of sediment. The use of multiple OSL replicate measurements is advocated as a strategy for checking for bioturbated sediment. Where significant OSL heterogeneity is found, caution should be taken with the derived OSL ages and further measurements at the single grain level are recommended. Observations from the linear dunes of the Kalahari show them to have no bedding structure and to have OSL heterogeneity similar to that shown from the bioturbated Texan and Florida sites. The Kalahari linear dunes could have therefore undergone hitherto undetected post-depositional sediment disturbance which would have implications for the established OSL chronology for the region

Accelerometer-determined physical activity, muscle mass, and leg strength in community-dwelling older adults

Introduction: The aim of this study was to describe the relationship between accelerometer-determined physical activity (PA), muscle mass, and lower-limb strength in community-dwelling older adults. Methods: Six hundred thirty-six community-dwelling older adults (66 ± 7 years) were studied. Muscle mass was measured using dual-energy x-ray absorptiometry, whilst lower limb strength was measured via dynamometry. We measured minutes/day spent in sedentary, light, moderate, and vigorous intensity activity using Actigraph GT1M accelerometers. Results: Participants spent a median of 583(Interquartile ratio (IQR) 522-646), 225(176-271), 27(12-45) and 0(0-0) min in sedentary, light, moderate, and vigorous activity, respectively. PA intensity was positively associated with both lean mass percentage and lower limb strength in a dose-response fashion. Sedentary activity was negatively associated with lean mass percentage, but not lower-limb strength. There was a positive association between PA and appendicular lean mass in men only. There was an interaction between age and activity; as age increased, the magnitude of the association of PA with lean mass percentage decreased. Those who adhered to the Australian Department of Health PA guidelines (moderate/vigorous PA >/=150 min/week) had greater lean mass percentage, appendicular lean mass, and lower limb strength. Conclusions: Using accelerometer technology, both the amount and intensity of accelerometer-determined PA had an independent, dose-response relationship with lean mass percentage and lower limb strength, with the largest effect for vigorous activity. Time spent in sedentary activity was negatively associated with lean mass percentage, but was not associated with lower limb strength. The magnitude of the association between PA and lean mass percentage decreased with age, suggesting that PA programmes may need to be modified with increasing age.Yi Chao Foong, Nabil Chherawala, Dawn Aitken, David Scott, Tania Winzenberg and Graeme Jone