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We present a re-discovery of G278.94+1.35a as possibly one of the largest known Galactic supernova remnants (SNRs) – that we name Diprotodon. While previously established as a Galactic SNR, Diprotodon is visible in our new Evolutionary Map of the Universe (EMU) and GaLactic and Extragalactic All-sky MWA (GLEAM) radio continuum images at an angular size of $3{{{{.\!^\circ}}}}33\times3{{{{.\!^\circ}}}}23$, much larger than previously measured. At the previously suggested distance of 2.7 kpc, this implies a diameter of 157$\times$152 pc. This size would qualify Diprotodon as the largest known SNR and pushes our estimates of SNR sizes to the upper limits. We investigate the environment in which the SNR is located and examine various scenarios that might explain such a large and relatively bright SNR appearance. We find that Diprotodon is most likely at a much closer distance of $\sim$1 kpc, implying its diameter is 58$\times$56 pc and it is in the radiative evolutionary phase. We also present a new Fermi-LAT data analysis that confirms the angular extent of the SNR in gamma rays. The origin of the high-energy emission remains somewhat puzzling, and the scenarios we explore reveal new puzzles, given this unexpected and unique observation of a seemingly evolved SNR having a hard GeV spectrum with no breaks. We explore both leptonic and hadronic scenarios, as well as the possibility that the high-energy emission arises from the leftover particle population of a historic pulsar wind nebula.
We report the discovery of a bow-shock pulsar wind nebula (PWN), named Potoroo, and the detection of a young pulsar J1638$-$4713 that powers the nebula. We present a radio continuum study of the PWN based on 20-cm observations obtained from the Australian Square Kilometre Array Pathfinder (ASKAP) and MeerKAT. PSR J1638$-$4713 was identified using Parkes radio telescope observations at frequencies above 3 GHz. The pulsar has the second-highest dispersion measure of all known radio pulsars (1 553 pc cm$^{-3}$), a spin period of 65.74 ms and a spin-down luminosity of $\dot{E}=6.1\times10^{36}$ erg s$^{-1}$. The PWN has a cometary morphology and one of the greatest projected lengths among all the observed pulsar radio tails, measuring over 21 pc for an assumed distance of 10 kpc. The remarkably long tail and atypically steep radio spectral index are attributed to the interplay of a supernova reverse shock and the PWN. The originating supernova remnant is not known so far. We estimated the pulsar kick velocity to be in the range of 1 000–2 000 km s$^{-1}$ for ages between 23 and 10 kyr. The X-ray counterpart found in Chandra data, CXOU J163802.6$-$471358, shows the same tail morphology as the radio source but is shorter by a factor of 10. The peak of the X-ray emission is offset from the peak of the radio total intensity (Stokes $\rm I$) emission by approximately 4.7$^{\prime\prime}$, but coincides well with circularly polarised (Stokes $\rm V$) emission. No infrared counterpart was found.
This article explores how complaint investigations undertaken by health ombudsman contribute to the improvement of the healthcare system. Using a qualitative case-study approach, semi-structured interviews were conducted with participants form the Scottish Public Services Ombudsman (SPSO) and three health boards within its jurisdiction. Health board participants were frustrated by complaints process used by the SPSO, in particular the lack of communication during an SPSO investigation especially when there were differences in clinical judgment. Using Braithwaite’s typologies of motivational postures and Hertogh’s models of administrative control it was found that a sense of capitulation was the primary determinant in ensuring health board compliance with SPSO recommendations and that the relationship between SPSO and health boards was predominantly coercive in nature. For the SPSO to be more effective in contributing to system improvement requires it to review its role and means of conducting complaint investigations.
Life relies on mutualistic relationships among species, and on the constant rejuvenation of Earth’s materials. Mutualistic cities would do the same thing, enhancing biodiversity, clean air, better soils, fresh water, and stronger communities. Today, however, cities are far from mutualistic. Currently, more than 4 billion people live in cities, and that number is rising quickly. These conglomerations of humanity consume vast Earth resources, and, worst yet, disgorge astonishing amounts of waste into the atmosphere, water, land and sea around them. Unlike "smart cities" that rely on sophisticated technology to monitor and respond to environmental conditions, and unlike "sustainable cities" that stress reduction and reuse, the concept of a "mutualistic city" emphasizes regenerative cycles and virtuous feedback loops. These cities are the key to our future.
To determine if the intention to perform an exercise at speed leads to beneficial alterations in kinematic and kinetic components of the movement in people with post-stroke hemiplegia.
Design:
Comparative study.
Setting:
Subacute metropolitan rehabilitation hospital.
Participants:
Convenience sample of patients admitted as an inpatient or outpatient with a diagnosis of stroke with lower limb weakness, functional ambulation category score ≥3, and ability to walk ≥14metres.
Methods:
Participants performed a single leg squat exercise on their paretic and nonparetic legs on a leg sled under three conditions: 1) self-selected speed (SS), 2) fast speed (FS), 3) jump squat (JS). Measures of displacement, flight time, peak concentric velocity, and muscle excitation (via electromyography) were compared between legs and conditions.
Results:
Eleven participants (age: 56 ± 17 years; median time since stroke onset: 3.3 [IQR 3,41] months) were tested. All participants achieved a jump during the JS, as measured by displacement and flight time respectively, on both their paretic (0.25 ± 0.16 m and 0.42 ± 0.18 s) and nonparetic (0.49 ± 0.36 m and 0.73 ± 0.28 s) legs; however it was significantly lower on the non-paretic leg (p < 0.05). Peak concentric velocity increased concordantly with intended movement speed (JS-FS paretic: 0.96 m/s, non-paretic: 0.54 m/s; FS-SS paretic 0.69 m/s, nonparetic 0.38 m/s; JS-SS paretic 1.66 m/s, non-paretic 0.92 m/s). Similarly, muscle excitation increased significantly (p < 0.05) with faster speed for the paretic and nonparetic vastus lateralis. For gastrocnemius, the only significant difference was an increase during nonparetic JS vs. SS and FS.
Conclusions:
Speed affects the kinematic and kinetic components of the movement. Performing exercises ballistically may improve training outcomes for people post-stroke.
Few figures loom larger in the early history of recorded sound than Enrico Caruso. Man and voice are ubiquitous in the making of gramophone markets, and conspicuous, too, as means of scholarly explanation by which a sound medium was born. In sound studies, Caruso has become a cipher for ‘audile technique’ (Jonathan Sterne's coinage), the bodily practices by which listeners came to engage musical media as something for their ears alone. This article inquires after what made Caruso a reproducible person. It portrays him as a singer celebrity deeply involved in his own reproduction through the media of caricature, sculpture, film and opera house. Through analysis of Caruso's productions for New York's Italian diaspora and farther afield, it argues that an ensemble of media meant he was reproduced beyond familiar, cosmopolitan circuits of operatic celebrity. Finally, it shows how politics of celebrity reproduction were transformed following Caruso's death, through the writing of history, into new imaginations and techniques for listening.
Who controls the land and minerals in the former Bantustans of South Africa - chiefs, the state or landholders? Disputes are taking place around the ownership of resources, decisions about their exploitation and who should benefit. With respect to all of these issues, the courts have become increasingly important. The contributors to Land, Law and Chiefs in Rural South Africa capture some of these intense contestations over land, law and political authority, focussing on threats to the rights of ordinary people. History and customary law feature strongly in most disputes and succession to chieftaincy is also frequently disputed. Judges have to make decisions in a context where rival claimants to property or office assert their own versions of history and custom. The South African constitution recognises customary law and the courts are attempting to incorporate and develop this branch of jurisprudence as 'living customary law'. Lawyers, community leaders and academics are called on to assist in researching cases around restitution, land rights and customary law. The chapters in this collection discuss legal cases and policy directions that have evolved since 1994. Some chapters analyse the increasing power of chiefs in the South African rural areas, while others suggest that the courts are giving support to popular rights over land and supporting local democratic processes. Contributors record significant pushback from groups that reject traditional authority. These political tensions are a central theme of the collection and thus serve as vital case studies in furthering our understanding of rights and restitution in South Africa.
In her 1984 ‘Cyborg Manifesto’, Donna Haraway declared: ‘the relation between organism and machine has been a border war’ in Western science and politics – which for her primarily amounted to a racist, male-dominated capitalism, as embodied by the notion of technological progress. Her manifesto identified that ‘The stakes in the border war have been the territories of production, reproduction and imagination’, each of these zones representing its own contentious interface between organism and machine within American post-industrial society: the encroachment of robots in industrial production; the use of test tubes for reproducing the body; the ascendancy of sci-fi imagination in literature and film. And in each case the battles weren’t being won by humans. Haraway was instead confident of a machine victory, pushing her towards a notorious conclusion: we are cyborgs.
Health technology assessment (HTA) is a cost-effective resource allocation tool in healthcare decision-making processes; however, its use is limited in low-income settings where countries fall short on both absorptive and technical capacity. This paper describes the journey of the introduction of HTA into decision-making processes through a case study revising the National Essential Medicines List (NEMLIT) in Tanzania. It draws lessons on establishing and strengthening transparent priority-setting processes, particularly in sub-Saharan Africa.
Methods
The concept of HTA was introduced in Tanzania through revision of the NEMLIT by identifying a process for using HTA criteria and evidence-informed decision making. Training was given on using economic evidence for decision making, which was then put into practice for medicine selection for the NEMLIT. During the revision process, capacity-building workshops were held with reinforcing messages on HTA.
Results
Between the period 2014 and 2018, HTA was introduced in Tanzania with a formal HTA committee being established and inaugurated followed by the successful completion and adoption of HTA into the NEMLIT revision process by the end of 2017. Consequently, the country is in the process of institutionalizing HTA for decision making and priority setting.
Conclusion
While the introduction of HTA process is country-specific, key lessons emerge that can provide an example to stakeholders in other low- and middle-income countries (LMICs) wishing to introduce priority-setting processes into health decision making.
Cognitive theories of generalised anxiety disorder (GAD) posit that cognitive and behavioural factors maintain the disorder. This study examined whether avoidance and safety behaviours mediated the relationship between cognitive factors and GAD symptoms. We also examined the reverse mediation model; that is, whether cognitive factors mediated the relationship between maladaptive behaviours and GAD symptoms. Undergraduate psychology students (N = 125 and N = 292) completed the Worry Behaviours Inventory (a recently developed measure of maladaptive behaviours associated with GAD), in addition to measures of intolerance of uncertainty, cognitive avoidance, metacognitive beliefs, and symptoms of GAD and depression. Analyses supported the reliability and validity of the WBI. We consistently found that engagement in maladaptive behaviours significantly mediated the relationship between cognitive factors and symptoms of GAD. The reverse mediation model was also supported. Our results are consistent with the contention that cognitive and behavioural factors contribute to GAD symptom severity.
Background: Cognitive models of generalized anxiety disorder (GAD) suggest that maladaptive behaviours may contribute to the maintenance of the disorder; however, little research has concentrated on identifying and measuring these behaviours. To address this gap, the Worry Behaviors Inventory (WBI) was developed and has been evaluated within a classical test theory (CTT) approach. Aims: As CTT is limited in several important respects, this study examined the psychometric properties of the WBI using an Item Response Theory approach. Method: A large sample of adults commencing treatment for their symptoms of GAD (n = 537) completed the WBI in addition to measures of GAD and depression symptom severity. Results: Patients with a probable diagnosis of GAD typically engaged in four or five maladaptive behaviours most or all of the time in an attempt to prevent, control or avoid worrying about everyday concerns. The two-factor structure of the WBI was confirmed, and the WBI scales demonstrated good reliability across a broad range of the respective scales. Together with previous findings, our results suggested that hypervigilance and checking behaviours, as well as avoidance of saying or doing things that are worrisome, were the most relevant maladaptive behaviours associated with GAD, and discriminated well between adults with low, moderate and high degrees of the respective WBI scales. Conclusions: Our results support the importance of maladaptive behaviours to GAD and the utility of the WBI to index these behaviours. Ramifications for the classification, theoretical conceptualization and treatment of GAD are discussed.
This review will outline the role of visiting cardiac surgical teams in low- and middle-income countries drawing on the collective experience of the authors in a wide range of locations. Requests for assistance can emerge from local programmes at a beginner or advanced stage. However, in all circumstances, careful pre-trip planning is necessary in conjunction with clinical and non-clinical local partners. The clinical evaluation, surgical procedures, and postoperative care all serve as a template for collaboration and education between the visiting and local teams in every aspect of care. Education focusses on both common and patient-specific issues. Case selection must appropriately balance the clinical priorities, safety, and educational objectives within the time constraints of trip duration. Considerable communication and practical challenges will present, and clinicians may need to make significant adjustments to their usual practice in order to function effectively in a resource-limited, unfamiliar, and multilingual environment. The effectiveness of visiting trips should be measured and constantly evaluated. Local and visiting teams should use data-driven evaluations of measurable outcomes and critical qualitative evaluation to repeatedly re-assess their interim goals. Progress invariably takes several years to achieve the final goal: an autonomous self-governing, self-financed, cardiac programme capable of providing care for children with complex CHD. This outcome is consistent with redundancy for the visiting trips model at the site, although fraternal, professional, and academic links will invariably remain for many years.