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This article introduces a special issue on Tim Hetherington and conflict imagery, which is the result of an international research project led by the University of Leeds and the Imperial War Museum. The project aimed to understand Hetherington's work by engaging with his associates, contemporary photojournalists, scholars, and the public. The special issue explores themes such as humanitarian photography, military masculinity, and the changing landscape of image-making during conflict. It includes articles that analyze Hetherington's representations of Afghanistan, focusing on aesthetic themes, soldiers' experiences, historical context, and audience interactions. The article concludes by encouraging further research using the Tim Hetherington collection. [Extracted from the article]

War photography scholarship tends to focus attention on photographers' lives and the thematic content of images. This study shifts the spotlight onto how varied members of the public respond to a body of work, in this case the photography and filmmaking of Tim Hetherington (1970-2011), whose archive the Imperial War Museum (IWM) obtained in 2017. We discuss findings from a number of visually-led focus groups with refugees, veterans, military family members, photography students and museum volunteers. Together we examined his image-making process with the groups to discover how they discussed notions such as intimacy, masculinity, the 'good' conflict photograph, and ethical dilemmas. We argue that engaging with multiple public perspectives through visual elicitation methods enhances curatorial knowledge and understanding of image-making practices in this specific context, whilst also offering insights for national museums more broadly on how dialogue with diverse communities can enrich the handling and display of new collections. [ABSTRACT FROM AUTHOR]

The transfer of nutrients and energy from carcasses to scavengers is an important ecosystem function. In marine ecosystems, mammal carcasses can represent a spatiotemporally restricted but substantial pulse in resource availability, as they are typically only briefly available to scavengers on the surface. Little is understood about how these scavengers respond to such pulses, or how inter-scavenger interactions may influence their behaviour. We describe scavenging interactions of procellariiform seabirds at a fresh and floating New Zealand Fur Seal Arctocephalus forsteri carcass, recently killed by a White Shark Carcharodon carcharias, over the continental slope of southeastern Australia. We highlight potential exclusive and facilitative interactions between the shark and various seabirds, which may play an important role in energy-transfer dynamics in surface pelagic environments. We also provide apparently novel descriptions of scavenging at a marine mammal carcass for six of the seven seabird species that attended the carcass. Further study of sea-surface scavenger behaviour, interactions, and ecology will provide valuable insights into energy-transfer dynamics in pelagic ecosystems. [ABSTRACT FROM AUTHOR]

Aseptic loosening and osteolysis continue to be a short- to mid-term problem for total ankle replacement (TAR) devices. The production of wear particles may contribute to poor performance, but their characteristics are not well understood. This study aimed to determine the chemical composition, size and morphology of wear particles surrounding failed TARs. A recently developed wear particle isolation method capable of isolating both high- and low-density materials was applied to 20 retrieved periprosthetic tissue samples from 15 failed TARs of three different brands. Isolated particles were imaged using ultra-high-resolution imaging and characterised manually to determine their chemical composition, size, and morphology. Six different materials were identified, which included: UHMWPE, calcium phosphate (CaP), cobalt chromium alloy (CoCr), commercially pure titanium, titanium alloy and stainless steel. Eighteen of the 20 samples contained three or more different wear particle material types. In addition to sub-micron UHMWPE particles, which were present in all samples, elongated micron-sized shards of CaP and flakes of CoCr were commonly isolated from tissues surrounding AES TARs. The mixed particles identified in this study demonstrate the existence of a complex periprosthetic environment surrounding TAR devices. The presence of such particles suggests that early failure of devices may be due in part to the multifaceted biological cascade that ensues after particle release. This study could be used to support the validation of clinically-relevant wear simulator testing, pre-clinical assessment of fixation wear and biological response studies to improve the performance of next generation ankle replacement devices. Total ankle replacement devices do not perform as well as total hip and knee replacements, which is in part due to the relatively poor scientific understanding of how they fail. The excessive production of certain types of wear debris is known to contribute to joint replacement failure. This is the first study to successfully isolate and characterise high- and low-density wear particles from tissues collected from patients with a failed total ankle replacement. This article includes the chemical composition and characteristics of the wear debris generated by ankle devices, all of which may affect their performance. This research provides clinically relevant reference values and images to support the development of pre-clinical testing for future total ankle replacement designs. [Display omitted] [ABSTRACT FROM AUTHOR]

• During Covid-19 people visited a wide range of nearby places to get away from everyday demands, without needing to travel. • People engaged with a wide range of activities in those places, but many activities were place dependent. • All place visits benefitted hedonic and eudemonic wellbeing, but outdoor activities were more beneficial than indoor activities. • Place and activity choices varied between people. Younger people and those living in urban areas visited less outdoor places. • To support wellbeing for all it is important to identify the variety of nearby places people visit and manage access and provision of such places. Being able to get away from everyday stressors and demands, even if close to home and just for a few minutes, is important for wellbeing. During the Covid-19 lockdown periods, people's ability to get away changed significantly. An increase in visits to nearby natural places is well documented. Little is known about other types of places people visited to get away. An online UK survey was conducted in 2020 (N = 850) investigating what places people visited to get away during the pandemic, what they did in those places, how place and activity choices were related to each other and to demographic variables, and to recalled hedonic and eudaimonic wellbeing during those visits. Participants visited a rich array of places and engaged in a variety of activities that supported their hedonic and eudaimonic wellbeing needs. Responses were grouped into four types of places (at home outdoors, at home indoors, away from home outdoors, and away from home indoors) and seven activity types (cognitive, walks, nature engagement, social activities, technology use, relaxing, and exercise). Place and activity choices were strongly linked. Visiting outdoor places was most beneficial for wellbeing (and most common), especially when it involved mindful engagement with nature (bird watching, gardening) or exercise. Staying indoors, engaging with technologies (computers, television) was least beneficial and more common among those with no degree or job, living in urban areas, and identifying as male. The findings demonstrate the importance of understanding place-activity interactions to support the wellbeing benefits derived from visits to places to get away. [ABSTRACT FROM AUTHOR]

Diabetic foot ulceration is linked to high amputation and mortality rates, with the substantial associated annual spend on the at-risk diabetic foot reflecting the intensive time and labour involved in treatment. Assessing plantar interactions and developing improved understanding of the formation pathways of diabetic ulceration is important to orthotic interventions and patient outcomes. Plantar skin surrogates which emulate the mechanical and tribological characteristics can help improve physical models of ulceration, reduce reliance on cadaveric use and inform more complex computational modelling approaches. The information available from existing studies to characterise plantar skin is limited, typically featuring ex-vivo representations of skin and subcutaneous tissue combined and given focus to shear studies with time dependency. The aim of this study is to improve understanding of plantar tissue mechanics by assessing the mechanical characteristics of plantar skin in two groups; (1) non-diabetic and (2) diabetic donors without the subcutaneous tissue attachment of previous work in this field. Digital image correlation was used to assess inherent skin pre-tension of the plantar rearfoot prior to dissection. Young's modulus, storage and loss moduli were tested for using tensile stress–strain failure analysis and tensile and compressive dynamic mechanical analysis, which was conducted on excised plantar rearfoot donor specimens for both disease state cohorts at frequencies reflecting those achieved in activities of daily living. Plantar skin thickness for donor specimens were comparable to values obtained using ultrasound acquired in vivo values. Median tensile storage and loss moduli, along with Young's modulus, was higher in the diabetic cohort. With a mean Young's modulus of 0.83 ± 0.49 MPa and 1.33 ± 0.43 MPa for non-diabetic and diabetic specimens respectively. Compressive studies showed consistency between cohorts for median storage and loss moduli. The outcomes from this study show mechanical characteristics of plantar skin without the involvement of subcuteanous tissues under reflective daily achieved loading regimes, showing differences in the non-diabetic and diabetic specimens trialled to support improved understanding of plantar tissue response under tribological interactions. [ABSTRACT FROM AUTHOR]

Decellularised porcine superflexor tendon (pSFT) has been characterised as a suitable scaffold for anterior cruciate ligament replacement, with dimensions similar to hamstring tendon autograft. However, decellularisation of tissues may reduce or damage extracellular matrix components, leading to undesirable biomechanical changes at a whole tissue scale. Although the role of collagen in tendons is well established, the mechanical contribution of glycosaminoglycans (GAGs) is less evident and could be altered by the decellularisation process. In this study, the contribution of GAGs to the tensile and compressive mechanical properties of pSFT was determined and whether decellularisation affected these properties by reducing GAG content or functionality. PSFTs were either enzymatically treated using chondroitinase ABC to remove GAGs or decellularised using previously established methods. Native, GAG-depleted and decellularised pSFT groups were then subjected to quantitative assays and biomechanical characterisation. In tension, specimens underwent stress relaxation and strength testing. In compression, specimens underwent confined compression testing. The GAG-depleted group was found to have circa 86% reduction of GAG content compared to native and decellularised groups. There was no significant difference in GAG content between native (3.75 ± 0.58 μg/mg) and decellularised (3.40 ± 0.37 μg/mg) groups. Stress relaxation testing discovered the time-independent and time-dependent relaxation moduli of the decellularised group were reduced ≥50% compared to native and GAG-depleted groups. However, viscoelastic behaviour of native and GAG-depleted groups resulted similar. Strength testing discovered no differences between native and GAG-depleted group's properties, albeit a reduction ∼20% for decellularised specimens' linear modulus and tensile strength compared to native tissue. In compression testing, the aggregate modulus was found to be circa 74% lower in the GAG-depleted group than the native and decellularised groups, while the zero-strain permeability was significantly higher in the GAG-depleted group (0.86 ± 0.65 mm4/N) than the decellularised group (0.03 ± 0.04 mm4/N). The results indicate that GAGs may significantly contribute to the mechanical properties of pSFT in compression, but not in tension. Furthermore, the content and function of GAGs in pSFTs are unaffected by decellularisation and the mechanical properties of the tissue remain comparable to native tissue. [Display omitted] • Confined compression was performed on decellularised tendon for the first time. • Decellularisation does not reduce glycosaminoglycan content in tendon. • Decellularisation does not adversely affect glycosaminoglycan function in tendon. • Glycosaminoglycans significantly contribute to tendon mechanical properties in compression. • Glycosaminoglycan loss in tendon does not significantly affect tensile mechanical properties. [ABSTRACT FROM AUTHOR]

Alumina ceramic heads have been previously shown to reduce polyethylene wear in comparison to cobalt chrome (CoCr) heads in artificial hip joints. However, there are concerns about the brittle nature of ceramics. It is therefore of interest to investigate ceramic-like coatings on metallic heads. The aim of this study was to compare the friction and wear of ultra-high molecular weight polyethylene (UHMWPE) against alumina ceramic, CoCr, and surface-engineered ceramic-like coatings in a friction simulator and a hip joint simulator. All femoral heads tested were 28 mm diameter and included: Biolox Forte alumina, CoCr, arc evaporative physical vapour deposition (AEPVD) chromium nitride (CrN) coated CoCr, plasma-assisted chemical vapour deposition (PACVD) amorphous diamond-like carbon (aDLC) coated CoCr, sputter CrN coated CoCr, reactive gas controlled arc (RGCA) AEPVD titanium nitride (TiN) coated CoCr, and Graphit-iC coated CoCr. These were articulated against UHMWPE acetabular cups in a friction simulator and a hip joint simulator. Alumina and CoCr gave the lowest wear volumes whereas the sputter coated CrN gave the highest. Alumina also had the lowest friction factor. There was an association between surface parameters and wear. This study indicates that surface topography of surface-engineered femoral heads is more important than friction and wettability in controlling UHMWPE wear. [ABSTRACT FROM AUTHOR]

Total joint replacement is a successful surgical intervention for the treatment of the degeneration of many joints, particularly the hip and knee. As the demand for joint replacement grows, and the life expectancy of the population increases, the performance requirements of these implants also changes. New materials, to improve longevity and enhance performance have been explored including PEEK and CFR-PEEK. This study investigated whether CFR-PEEK and PEEK were appropriate materials for total joint replacement by examining wear performance in simple configuration studies articulating against cobalt chrome under a range of cross-shear and contact pressure conditions. Simple geometry pin on plate studies were conducted for one million cycles for each test condition, with the contact pressure and cross-shear conditions representing a range in which the material may need to operate in-vivo. The wear factor for PEEK was significantly higher than CFR-PEEK and conventional polyethylene under all test conditions. Both PEEK and CFR-PEEK wear were influenced by contact pressure, with the highest wear factors for both materials measured at the highest pressure conditions. PEEK appeared to have a cross-shear dependent wear response, but this was not observed for the CFR-PEEK material. This study has further characterised the wear performance of two materials that are gaining interest for total joint replacement. The wear performance of the PEEK material showed poorer wear performance compared to polyethylene when articulating with a metal counterface, but the performance of the CFR-PEEK material suggested it may provide a suitable alternative to polyethylene in some applications. The wear performance of CFR-PEEK was poorer than polyethylene when it was used as the plate, when there was translation of the contact zone over the surface of the CFR-PEEK plate. This has implications for applications in low conforming contacts, such as lower conformity knee replacement. [ABSTRACT FROM AUTHOR]

This paper provides an introduction to the biomechanics of the ankle, introducing the bony anatomy involved in motion of the foot and ankle. The complexity of the ankle anatomy has a significant influence on the biomechanical performance of the joint, and this paper discusses the motions of the ankle joint complex, and the joints at which it is proposed they occur. It provides insight into the ligaments that are critical to the stability and function of the ankle joint. It describes the movements involved in a normal gait cycle, and also highlights how these may change as a result of surgical intervention such as total joint replacement or fusion. [ABSTRACT FROM AUTHOR]

The increase in the global diabetic population is leading to an increase in associated complications such as diabetic foot ulceration (DFU), associated amputations, morbidity, which substantial treatment costs. Early identification of DFU risk is therefore of great benefit. International guidelines recommend off-loading is the most important intervention for healing and prevention of DFU, with current research focused on pressure measurement techniques. The contribution of strain to DFU formation is not well understood due to challenges in measurement. The limited data available in the literature suggest that plantar strain is involved in ulcer formation. As a consequence, there is a need for plantar strain measurement systems to advance understanding and inform clinical treatment. A method was developed to determine plantar strain based on a Digital Image Correlation (DIC) approach. A speckle pattern is applied to the plantar aspect of the foot using a low ink transference method. A raised walkway with transparent panels is combined with a calibrated camera to capture images of the plantar aspect throughout a single stance phase. Plantar strain is then determined using 2D DIC and custom analysis summarises these data into clinically relevant metrics. A feasibility study involving six healthy participants was used to assess the efficacy of this new technique. The feasibility study successfully captured plantar surface strain characteristics continuously throughout the stance phase for all participants. Peak mean and averaged mean strains varied in location between participants when mapped into anatomical regions of plantar interest, ranging from the calcaneus to the metatarsal heads and hallux. This method provides the ability to measure plantar skin strain for use in both research and clinical environments. It has the potential to inform improved understanding of the role of strain in DFU formation. Further studies using this technique can support these ambitions and help differentiate between healthy and abnormal plantar strain regimes. [Display omitted] [ABSTRACT FROM AUTHOR]

Despite emancipatory ideals introduced by Enlightenment intellectuals, social progress has entailed a regressive character. Deprivation and marginalization continue to reflect the status quo despite the extension of formal universal rights to most everyone in the U.S. Our intent is to synthesize an often compartmentalized literary body on class, race, and gender and illuminate the independent and interlocking nature of these inequalities. Our argument is divided into two sections. We first highlight distinct realities of class, race, and gender conflict by raising questions of race and gender left unanswered by some Marxists. Then we analyze the regressive character of race and gender progress under a capitalist system built upon an Enlightened ethos. Our analysis reveals that historically, racial and gender struggles have been left to defend the mere human dignity of people of color and women alike, while undergirding issues of the political economy remain unaddressed and material interests of the elite preserved. To this end, contemporary abstractions of liberty, freedom, and justice do not serve emancipatory interests but implicitly endorse domination in the name of liberation. We conclude with a defense of Enlightenment despite this inversion. Such ideals have never been fully realized, but this does not mean they could not be. [ABSTRACT FROM AUTHOR]

The article focuses on the protection of indigenous cultural heritage in the Australian state of Queensland, which was first occupied by Aboriginal and Torres Strait Islanders. The article discusses the Australian Constitution and legislative power of states to protect Aboriginal cultural heritage, the Aboriginal Cultural Heritage Act of 2003 (ACHA) and recommendations for the ACHA including returning the ownership of Aboriginal cultural to Aboriginal people and uniform national legislation.

Abstract: The clinical incidence of squeaking has been reported with increasing frequency, with ceramic-on-ceramic bearings seemingly most affected. This study investigated potential causes of squeaking in hard-on-hard hip bearings through 2 sets of experimental conditions. Bearing clearance appeared to affect the incidence of squeaking in metal-on-metal surface arthroplasties. The addition of third-body particles to the interface for total hip arthroplasties also affected the incidence of squeaking. In both studies, the incidence of squeaking correlated well with elevated friction. The findings of this study suggest that a likely cause of squeaking in the hip arthroplasty is adverse tribological conditions caused by suboptimal lubrication. There are numerous factors that may cause the suboptimal lubrication, and therefore, it is unlikely that an individual cause for squeaking will be identified. [Copyright &y& Elsevier]

The article discusses issues related to the valuation of shares of minority shareholders incase of oppression of minority shareholders. It mentions that minority shareholders can seek compensation under section 233 of the Corporations Act 2001 of Australia and the Companies Act 2006 in Great Britain. It mentions that majority shareholders of a company are forced to buy out shares of minority shareholders and states that shares are valued at fair value, which is different from market fair value.