698 research outputs found
Governing by Executive Order During the Covid-19 Pandemic: Preliminary Observations Concerning the Proper Balance Between Executive Orders and More Formal Rule Making
As the United States entered 2021, almost all fifty states were still operating under a state of emergency due to COVID-19 more than nine months later. Governors using emergency powers provided to them under their respective emergency disaster statutes and state constitutions continued to govern their state by executive order. These executive orders have had significant impacts on citizens’ everyday lives including stay-at-home orders, limits on non-essential gatherings, non-essential business closures and moratoriums on evictions. And these emergency orders have been opposed at almost every turn from citizens gathering in public protest shouting “Liberate Michigan,” to constitutional legal challenges to these orders. Even with three promising vaccines receiving emergency authorization at the time of this article’s submission, it will be months or longer before life returns to normal. Therefore, it becomes incumbent to ask the question whether governors should continue to wield this emergency power or whether state legislatures and/or state agencies should take on more responsibility. In answer to this question, this article concludes that governors should use executive orders in some measure as long as COVID-19 is being transmitted in their communities but not for all areas. Since COVID-19 is a highly contagious disease and is difficult to contain, governors need to be able to quickly and nimbly issue orders to curb transmission as long as there is a reasonable check on their power to do so. However, state legislatures and/or state agencies should enact emergency statutes or regulations following the more formal rule making process in areas that do not require immediate action such as requiring facial coverings in public spaces. This article draws its conclusion by examining three key areas. First, most governors have a meaningful check on their emergency powers from both the judiciary and the state legislature. Second, governors and litigants can learn from prior cases to ensure executive orders do not single out a group or unnecessarily burden another. Third, since some states have had success in enacting emergency regulations, statutes or guidelines concerning COVID-19, more states should follow suit
Informing tropical mammal conservation in human-modified landscapes using remote technologies and hierarchical modelling
The aggressive expansion of anthropogenic activities is placing increasing pressure on biodiversity, particularly in tropical regions. Here, conservation efforts are hindered by poor understanding of species ecology and the failure of policy instruments to account for multiple stressors of land-use change. While protected areas are central to conservation strategies, there is a general consensus that the future of tropical biodiversity will be determined by how well modified landscapes are managed. In this thesis I advance our understanding of biodiversity persistence in modified tropical landscapes to inform emerging incentive-based policy mechanisms and supply-chain initiatives. Capitalising on recent advances in remote-sensing and hierarchical occupancy modelling, I provide a spatial appraisal of biodiversity in a modified landscape in Sabah, Malaysian Borneo. Fieldwork was conducted at the Stability of Altered Forest Ecosystems (SAFE) project, a large-scale landscape modification experiment, comprising a degradation gradient of old growth forest, selectively logged forest, remnant forest patches and oil palm plantations. The assessment focused on camera-trapping of tropical mammals, as they are sensitive to anthropogenic stressors, occupy key trophic positions, and prioritised in conservation. In Chapter 2 I link mammal occupancy data to airborne multispectral remote-sensing information to show how the conservation value of modified landscapes is dictated by the intensity of the underlying land-use. Logged forests retained appreciable levels of mammal diversity, and oil palm areas were largely devoid of forest specialists and threatened taxa. Moreover, many mammal species disproportionately occupied forested areas that retained old growth structural characteristics. The most influential structural measures accounted for vertical and horizontal components in environmental space, which cannot currently be derived from conventional satellite data. Using a novel application of ecological threshold analysis, I demonstrate how multispectral data and multi-scale occupancy models can help identify conservation and restoration areas in degraded forests. In Chapter 3 I assess the potential for carbon-orientated policy mechanisms (High Carbon Stock, HCS, Approach and REDD+) to prioritise high carbon areas with corresponding biodiversity value in highly modified landscapes. The areas of highest carbon value prioritised via HCS supported comparable species diversity to old growth forest. However, the strength, nature and extent of the biodiversity co-benefit was dependent on how carbon was characterised, the spatial resolution of carbon data, and the species considered. In Chapter 4 I further scrutinised HCS protocols to evaluate how well they delineated high priority forest patches that safeguard species most vulnerable to land-use change (i.e. IUCN threatened species). The minimum core area required to define a high priority patch (100 ha) supported only 35% of the mammal community. In fact the core area criterion would need to increase to 3,199 ha in order to sustain intact mammal assemblages, and an order of magnitude higher if hunting pressure was considered. These findings underline the importance of integrating secondary disturbance impacts into spatial conservation planning. Provided landscape interventions are directed to where they will have the greatest impact, they can be financially sustaining and garner local support for conservation. To this end I provide recommendations to guide policy implementation in modified tropical landscapes to support holistic conservation strategies
A validation data-set and suggested validation protocol for ship evacuation models
An evacuation model validation data-set collected as part of the EU FP7 project SAFEGUARD is presented. The data was collected from a cruise ship operated by Royal Caribbean International (CS). The trial was a semi-unannounced assembly trial conducted at sea and involved some 2500 passengers. The trial took place at an unspecified time however, passengers were aware that on their voyage an assembly exercise would take place. The validation data-set consists of passenger; response times, starting locations, end locations and arrival times in the assembly stations. The validation data were collected using a novel data acquisition system consisting of ship-mounted beacons, each emitting unique Infra-Red (IR) signals and IR data logging tags worn by each passenger. The results from blind simulations using maritimeEXODUS for the assembly trial are presented and compared with the measured data. Three objective measures are proposed to assess the goodness of fit between the predicted model data and the measured data
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Investigating the impact of culture on evacuation response behaviour
The aim of this work was to investigate whether social culture impacts how people respond to an evacuation alarm. As part of this work four unannounced library evacuations were conducted in the Czech Republic, Turkey, Poland and the UK. In an attempt to isolate social culture as the primary independent variable across the trials, the key parameters that are known to influence Response Phase behaviour and performance e.g. population demographics, type of structure, alarm system, etc were controlled across the trials. Response Phase behaviour was determined for a total of 477 individuals, 192 from Poland, 51 from Turkey, 70 from the Czech Republic and 104 from the UK. The results suggest that there are significant differences in the nature of the population behaviour during the Response Phase across the four trials. On average, the population with the quickest to the slowest response times are: Turkey, Poland, UK and Czech Republic. When applied to a simulated evacuation, the observed differences in response time distribution for the national groups resulted in significantly different evacuation performance
The effects of upper- vs. lower-body aerobic exercise on perceived pain in individuals with chronic knee pain: a randomised crossover trial
Background and objectivesSome patients with chronic knee pain experience an increase in knee pain following a single bout of exercise involving their knee joint, which can negatively affect exercise adherence and thus result in reduced overall health and lack of disease management. We want to determine whether a single bout of upper-body (UB) aerobic arm-ergometry exercise is effective in reducing the experience of pain in those with chronic knee pain compared with lower-body (LB) aerobic leg ergometry exercise.MethodsA total of 19 individuals (women = 11, men = 8; age = 63 ± 8 years; body mass index = 24 ± 3 kg/m2) who suffered from chronic knee pain for ≥3 months took part in this study. Arm-ergometry and cycle-ergometry exercises were performed for 30 min at a moderate intensity, separated by 7 days. Pain intensity was assessed by means of a visual analogue scale (VAS) pre- and post-exercise and for 7 days post-exercise. Pressure pain threshold (PPT) and mechanical detection threshold (MDT) were measured pre- and post-exercise at both local and distal anatomical sites. Data are presented as mean ± SD.ResultsVAS pain was significantly reduced (p = 0.035) at 1 day post-exercise following the UB exercise trial (−1.4 ± 0.8) when compared with the LB exercise trial (+0.1 ± 2.1). Both UB and LB exercises were effective in reducing local and distal PPT. MDT responses were heterogeneous, and no differences between the UB and LB exercise conditions were noted.ConclusionAn acute bout of upper-body aerobic arm-ergometry exercise evoked a significant decrease in the affected knee joint pain in individuals with chronic knee pain of up to 24 h/1 day post-exercise compared with lower-body aerobic exercise. While the exact mechanisms remain unclear, upper-body exercise may offer a viable, novel therapeutic treatment for patients with chronic knee pain
Breast cancer metastasis to the stomach may mimic primary gastric cancer: report of two cases and review of literature
<p>Abstract</p> <p>Background</p> <p>The stomach is an infrequent site of breast cancer metastasis. It may prove very difficult to distinguish a breast cancer metastasis to the stomach from a primary gastric cancer on the basis of clinical, endoscopic, radiological and histopathological features. It is important to make this distinction as the basis of treatment for breast cancer metastasis to the stomach is usually with systemic therapies rather than surgery.</p> <p>Case presentations</p> <p>The first patient, a 51 year old woman, developed an apparently localised signet-ring gastric adenocarcinoma 3 years after treatment for lobular breast cancer with no clinical evidence of recurrence. Initial gastric biopsies were negative for both oestrogen and progesterone receptors. Histopathology after a D2 total gastrectomy was reported as T4 N3 Mx. Immunohistochemistry for Gross Cystic Disease Fluid Protein was positive, suggesting metastatic breast cancer. The second patient, a 61 year old woman, developed a proximal gastric signet-ring adenocarcinoma 14 years after initial treatment for breast cancer which had subsequently recurred with bony and pleural metastases. In this case, initial gastric biopsies were positive for both oestrogen and progesterone receptors; subsequent investigations revealed widespread metastases and surgery was avoided.</p> <p>Conclusion</p> <p>In patients with a history of breast cancer, a high index of suspicion for potential breast cancer metastasis to the stomach should be maintained when new gastrointestinal symptoms develop or an apparent primary gastric cancer is diagnosed. Complete histopathological and immunohistochemical analysis of the gastric biopsies and comparison with the original breast cancer pathology is important.</p
Transonic Investigation of Two-Dimensional Nozzles Designed for Supersonic Cruise
An experimental and computational investigation has been conducted to determine the off-design uninstalled drag characteristics of a two-dimensional convergent-divergent nozzle designed for a supersonic cruise civil transport. The overall objectives were to: (1) determine the effects of nozzle external flap curvature and sidewall boattail variations on boattail drag; (2) develop an experimental data base for 2D nozzles with long divergent flaps and small boattail angles and (3) provide data for correlating computational fluid dynamic predictions of nozzle boattail drag. The experimental investigation was conducted in the Langley 16-Foot Transonic Tunnel at Mach numbers from 0.80 to 1.20 at nozzle pressure ratios up to 9. Three-dimensional simulations of nozzle performance were obtained with the computational fluid dynamics code PAB3D using turbulence closure and nonlinear Reynolds stress modeling. The results of this investigation indicate that excellent correlation between experimental and predicted results was obtained for the nozzle with a moderate amount of boattail curvature. The nozzle with an external flap having a sharp shoulder (no curvature) had the lowest nozzle pressure drag. At a Mach number of 1.2, sidewall pressure drag doubled as sidewall boattail angle was increased from 4deg to 8deg. Reducing the height of the sidewall caused large decreases in both the sidewall and flap pressure drags. Summar
How long do revised and multiply revised knee replacements last?:A retrospective observational study of the National Joint Registry
Background
Knee replacements are common and effective operations but patients that undergo this intervention are at risk of needing subsequent costly and often complex revision surgery with poorer outcomes than primary surgery. The treatment pathway over the life of the patient in terms of risk of revision and re-revisions is poorly described. We aim to provide detailed information on the longevity of revision surgery.
Methods
We did a retrospective observational registry-based study of the National Joint Registry in England and Wales, UK. Knee replacement revision procedures linked to a primary episode were included; duplicates, records with missing information, and records with an unknown sequence of revision procedures were not included. Kaplan-Meier estimates were used to determine the cumulative probability of revision and subsequent re-revisions following primary knee replacement. Analyses were stratified by age and gender, and the influence of time from first to second revision on the risk of further revision was explored.
Findings
Between April 1, 2003, and Dec 31, 2018, 33 292 revision knee replacements were linked with a primary episode. Revision rates of revision knee replacements were higher in males than females at 10 years (20·0% [95% CI 19·0–21·0] vs 14·8% [13·9–15·6]) and higher in younger patients at 10 years (females younger than 55 years 21·0% [18·6–23·5] vs females aged 75–79 years 8·3% [6·8–10·2]; males younger than 55 years 26·6% [23·9–29·5] vs males aged 75–79 years 13·6% [10·6–17·5]). 19·9% (18·3–21·5) of first revisions were revised again within 13 years, 20·7% (19·1–22·4) of second revisions were revised again within 5 years, and 20·7% (17·1–24·9) of third revisions were revised again within 3 years. A shorter time between revision episodes was associated with earlier subsequent revision.
Interpretation
Males and younger patients are at higher risk of multiple revisions. Patients who undergo a revision have a steadily increasing risk of further revision the more procedures they undergo, and each subsequent revision lasts for approximately half the time of the previous one. Although knee replacements are effective for improving pain and function and usually last a remarkably long time, if they are revised, successive revisions are progressively and markedly less successfu
A new species in the tree genus Polyceratocarpus (Annonaceae) from the Udzungwa Mountains of Tanzania
Polyceratocarpus askhambryan-iringae, an endemic tree species of Annonaceae from the Udzungwa Mountains of Tanzania, is described and illustrated. The new species is identified as a member of the genus Polyceratocarpus by the combination of staminate and bisexual flowers, axillary inflorescences, subequal outer and inner petals, and multi-seeded monocarps with pitted seeds. From Polyceratocarpus scheffleri, with which it has previously been confused, it differs in the longer pedicels, smaller and thinner petals, shorter bracts, and by generally smaller, less curved monocarps that have a clear stipe and usually have fewer seeds. Because Polyceratocarpus askhambryan-iringae has a restricted extent of occurrence, area of occupancy, and ongoing degradation of its forest habitat, we recommend classification of it as Endangered (EN) on the IUCN Red List
Spectral subtraction and enhancement for torsional waves propagating in coated pipes
Ultrasonic guided waves are routinely used for inspection of pipelines. The technique is well established for uncoated pipes where attenuation is very low. However, when the pipe is coated, buried or immersed, sound energy will be absorbed by the coating or radiate into the surrounding medium. Attenuation will increase and the scanning distance will be significantly reduced. The noise level can also increase when the condition of the coating material degrades with age and the bonding condition between pipe and coating becomes unevenly distributed. The increase of attenuation ratio and noise level therefore makes the inspection of ultrasonic waves propagating in coated and buried pipelines particularly difficult. It is often desirable to identify small features amongst the noise floor. To improve signal to noise ratio under these conditions, two techniques are proposed for the study of the propagation of torsional waves in Denso Tape coated pipes. A frequency domain, backward wave cancelling algorithm is used to eliminate the reflected waves coming from the backward direction and clean up the signal. On this basis, a spectral subtraction method is used, which requires knowledge of a small section of pipe that includes no real features, so that the signal from this region provides the characteristic noise signature of the pipe itself. The spectrum of the noise signature is calculated and then subtracted from the total signal using a sliding window technique. Furthermore, a signal region, for instance the reflected signal from a pipe weld or end, is specified. This represents the characteristic of the incident signal and any signal similar in shape will be enhanced using the sliding window technique. These two techniques serve to reduce the noise floor and enhance small signals that may be buried in it. This is important for ultrasonic non-destructive testing applications in coated and buried pipes.The Innovate UK project (Ultrasonic Nuclear Inspection
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