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To examine differences in surgical practices between salaried and fee-for-service (FFS) surgeons for two common degenerative spine conditions. Surgeons may offer different treatments for similar conditions on the basis of their compensation mechanism.
Methods:
The study assessed the practices of 63 spine surgeons across eight Canadian provinces (39 FFS surgeons and 24 salaried) who performed surgery for two lumbar conditions: stable spinal stenosis and degenerative spondylolisthesis. The study included a multicenter, ambispective review of consecutive spine surgery patients enrolled in the Canadian Spine Outcomes and Research Network registry between October 2012 and July 2018. The primary outcome was the difference in type of procedures performed between the two groups. Secondary study variables included surgical characteristics, baseline patient factors, and patient-reported outcome.
Results:
For stable spinal stenosis (n = 2234), salaried surgeons performed statistically fewer uninstrumented fusion (p < 0.05) than FFS surgeons. For degenerative spondylolisthesis (n = 1292), salaried surgeons performed significantly more instrumentation plus interbody fusions (p < 0.05). There were no statistical differences in patient-reported outcomes between the two groups.
Conclusions:
Surgeon compensation was associated with different approaches to stable lumbar spinal stenosis and degenerative lumbar spondylolisthesis. Salaried surgeons chose a more conservative approach to spinal stenosis and a more aggressive approach to degenerative spondylolisthesis, which highlights that remuneration is likely a minor determinant in the differences in practice of spinal surgery in Canada. Further research is needed to further elucidate which variables, other than patient demographics and financial incentives, influence surgical decision-making.
Background: Cervical spondylotic myelopathy (CSM) is the leading cause of spinal cord impairment. In a public healthcare system, wait times to see spine specialists and eventually access surgical treatment for CSM can be substantial. The goals of this study were to determine consultation wait times (CWT) and surgical wait times (SWT), and identify predictors of wait time length. Methods: Consecutive patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN) prospective and observational CSM study from March 2015 to July 2017 were included. A data-splitting technique was used to develop and internally validate multivariable models of potential predictors. Results: A CSORN query returned 264 CSM patients for CWT. The median was 46 days. There were 31% mild, 35% moderate, and 33% severe CSM. There was a statistically significant difference in median CWT between moderate and severe groups; 207 patients underwent surgical treatment. Median SWT was 42 days. There was a statistically significant difference in SWT between mild/moderate and severe groups. Short symptom duration, less pain, lower BMI, and lower physical component score of SF-12 were predictive of shorter CWT. Only baseline pain and medication duration were predictive of SWT. Both CWT and SWT were shorter compared to a concurrent cohort of lumbar stenosis patients (p <0.001). Conclusions: Patients with shorter duration (either symptoms or medication) and less neck pain waited less to see a spine specialist in Canada and to undergo surgical treatment. This study highlights some of the obstacles to overcome in expedited care for this patient population.
We propose a 3D-printable soft, stretchable, and transparent hydrogel-elastomer device that is able to detect simulated ‘nerve’ signals. The signal is passed to a conductive hydrogel electrode through a non-contact method of capacitive coupling through polydimethylsiloxane (PDMS). We demonstrate that the device is able to detect sinusoidal waveforms passed through a simulated ‘nerve’ made from conductive hydrogel over a range of frequencies (1 kHz – 1 MHz). Analysis of signal detection showed a correlation to the electrode contact area and a Vin/Vout of larger than 10%. This provides the framework for the future development of a soft, 3D-printable, capacitive coupling device that can be used as a cuff electrode for detecting peripheral nerve signals.
Capital accumulation in South Africa started off as a process of ‘accumulation by dispossession’ (Harvey, 2010: 48–49). War, violence, predation, thievery, criminality, fraud … these were the means by which the indigenous people were dispossessed of their communal lands, and by which the basis to wealth in this country passed into the hands of the capitalists.
South Africa was incorporated into the world economy as an enclave – as a colonial economy established by imperialist class interests primarily for the exploitation of its raw material resources (Mhone, 2001). Our economy was typically characterised by a capital-intensive sector co-existing with a capital-starved traditional economy. Although often described as ‘dual’, they are by no means ‘separate’. The capitalist sector, particularly the gold mining industry, was critically dependent on the traditional economy for the ongoing supply of ‘ultra-cheap, ultra-exploitable’ supplies of labour (Johnstone, 1976). By providing a subsistence base, the traditional economy in effect lowered the minimal acceptable wage threshold of labour (Wallerstein, 2003), thereby ensuring the very existence and sustainability of the capitalist system in this country.
Herein lies the root of our so-called National Question for, historically, class rule in South Africa has been about institutionalising ‘systems of duality’ in our society in order to extend and maintain the conditions of exploitation. It is against this background that divide and rule as a fundamental mechanism of class rule needs to be understood.
Capitalism's interests were served by dividing the nation, by perpetuating a core-periphery duality in society and the economy.
Historically, this has created the conditions of struggle in South Africa. It explains why opposition that was predicated on the principle of ‘one single South African nation’ has had revolutionary implications – why a call for a non-racial democracy was a fundamental threat to the very basis of capital accumulation.
Tebuthiuron (N-[5-(1,1-dimethylethyl)-1,3,4-thiadiozol-2-yl]-N,N′-dimethylurea} pellets (20% ai) applied at 0.6, 1.1, or 2.2 kg ai/ha in the spring at two locations and in the fall at a third location on the South Texas Plains did not significantly decrease buffelgrass (Cenchrus ciliaris L. # PESCI) standing crop or foliar cover compared to untreated areas. Buffelgrass standing crop was reduced for 8 months after application of 3.3 and 4.4 kg ai/ha of tebuthiuron to a sandy clay loam in the spring, but the same rates did not reduce standing crop after application to clay loam in the fall. However, buffelgrass foliar cover was reduced following application of 3.3 kg ai/ha or more of the herbicide, regardless of soil. Tebuthiuron applied at 2.2, 3.3, or 4.4 kg ai/ha to sandy clay loam soils killed buffelgrass plants in spots, but production by larger surviving plants compensated for reduction in plant density where 2.2 or 3.3 kg ai/ha were applied.
Sediments exposed at Epiguruk, a large cutbank on the Kobuk River about 170 km inland from Kotzebue Sound, record multiple episodes of glacial-age alluviation followed by interstadial downcutting and formation of paleosols. Vertebrate remains from Epiguruk include mammoth, bison, caribou, an equid, a canid, arctic ground squirrel, lemmings, and voles. Radiocarbon ages of bone validated by concordant ages of peat and wood span the interval between about 37,000 and 14,000 yr B.P. The late Pleistocene pollen record is dominated by Cyperaceae, with Artemisia, Salix, Betula, and Gramineae also generally abundant. The fossil record from Epiguruk indicates that the Kobuk River valley supported tundra vegetation with abundant riparian willows during middle and late Wisconsin time. Large herbivores were present during the height of late Wisconsin glaciation as well as during its waning stage and the preceding interstadial interval. The Kobuk River valley would have been a favorable refugium for plants, animals, and possibly humans throughout the last glaciation.
The Canyon Creek vertebrate-fossil locality is an extensive road cut near Fairbanks that exposes sediments that range in age from early Wisconsin to late Holocene. Tanana River gravel at the base of the section evidently formed during the Delta Glaciation of the north-central Alaska Range. Younger layers and lenses of fluvial sand are interbedded with arkosic gravel from Canyon Creek that contains tephra as well as fossil bones of an interstadial fauna about 40,000 years old. Solifluction deposits containing ventifacts, wedge casts, and rodent burrows formed during a subsequent period of periglacial activity that took place during the maximum phase of Donnelly Glaciation about 25,000–17,000 years ago. Overlying sheets of eolian sand are separated by a 9500-year-old paleosol that may correlate with a phase of early Holocene spruce expansion through central Alaska. The Pleistocene fauna from Canyon Creek consists of rodents (indicated by burrows), Mammuthus primigenius (woolly mammoth), Equus lambei (Yukon wild ass), Camelops hesternus (western camel), Bison sp. cf. B. crassicornis (large-horned bison), Ovis sp. cf.O. dalli (mountain sheep), Canis sp. cf. C. lupus (wolf), Lepus sp. cf. L. othus or L. arcticus (tundra hare), and Rangifer sp. (caribou). This assemblage suggests an open landscape in which trees and tall shrubs were either absent or confined to sheltered and moist sites. Camelops evidently was present in eastern Beringia during the middle Wisconsin interstadial interval but may have disappeared during the following glacial episode. The stratigraphic section at Canyon Creek appears to demonstrate that the Delta Glaciation of the north-central Alaska Range is at least in part of early Wisconsin age and was separated from the succeeding Donnelly Glaciation by an interstadial rather than interglacial episode.
Dense, controlled-impedance, superconducting cables with small cross-sections are desirable, especially for quantum computing applications. In this study, superconductivity properties, rf microwave response and mechanical reliability performance of embedded Nb dc cables and Nb microstrip transmission line resonators with different thicknesses of polyimide PI-2611 encapsulation layers (0, 4 and 8 μm) have been investigated. Critical temperature (Tc) and critical current (Ic) of embedded Nb dc cables are ∼ 8.2 K and ∼ 0.2 A, respectively. Embedded Nb resonators yield high loaded quality factor (QL), with values as high as 14481 at ∼ 1.2 K and at a fundamental resonance of ∼ 2 GHz. From mechanical fatigue testing, we have observed that a polyimide encapsulation layer can effectively enhance the mechanical reliability of superconducting Nb flexible cables.
We report the use of a novel extrusion tip that allows for the omnidirectional printing of eutectic gallium-indium (eGaIn) alloy onto the surface of hydrogel materials into complex 2-dimensional patterns. The use of these printed soft “wires” as an electrothermal heating element for soft robotics purposes was explored. Heating of the eGaIn structures encapsulated in an alginate/acrylamide ionic-covalent entanglement hydrogel was measured by a thermal imaging camera. It was determined that eGaIn is a suitable material for use in future soft robotics applications as an electrothermal heating element to actuate thermally responsive N-isoproylacrylamide hydrogels.
Structural brain magnetic resonance imaging (MRI) traits share part of their genetic variance with cognitive traits. Here, we use genetic association results from large meta-analytic studies of genome-wide association (GWA) for brain infarcts (BI), white matter hyperintensities, intracranial, hippocampal, and total brain volumes to estimate polygenic scores for these traits in three Scottish samples: Generation Scotland: Scottish Family Health Study (GS:SFHS), and the Lothian Birth Cohorts of 1936 (LBC1936) and 1921 (LBC1921). These five brain MRI trait polygenic scores were then used to: (1) predict corresponding MRI traits in the LBC1936 (numbers ranged 573 to 630 across traits), and (2) predict cognitive traits in all three cohorts (in 8,115–8,250 persons). In the LBC1936, all MRI phenotypic traits were correlated with at least one cognitive measure, and polygenic prediction of MRI traits was observed for intracranial volume. Meta-analysis of the correlations between MRI polygenic scores and cognitive traits revealed a significant negative correlation (maximal r = 0.08) between the HV polygenic score and measures of global cognitive ability collected in childhood and in old age in the Lothian Birth Cohorts. The lack of association to a related general cognitive measure when including the GS:SFHS points to either type 1 error or the importance of using prediction samples that closely match the demographics of the GWA samples from which prediction is based. Ideally, these analyses should be repeated in larger samples with data on both MRI and cognition, and using MRI GWA results from even larger meta-analysis studies.
Composed in the twelfth century by the leading Muslim jurist Burhan al-Din al-Marghinani (1135–97), the original Arabic al-Hidāyah remains a central text of Islamic personal law. This English translation, from a Persian version of the work, was prepared by the orientalist Charles Hamilton (c.1752–92) for the East India Company in 1791. Although since superseded, it remains a fascinating document in the history of colonial jurisprudence. The legal system was central to the entrenchment of British rule in India, providing the framework for active control of civil administration and the courts. Translations of Islamic texts were intended to remove the language barrier for colonial officials, and blurred British and native law for the first time. Volume 2 contains sections on punishments, larceny, the rules of war, foundlings, the absconding of slaves, missing persons, partnerships, sales, bail, the transfer of debts, the duties of judges, and evidence.
Composed in the twelfth century by the leading Muslim jurist Burhan al-Din al-Marghinani (1135–97), the original Arabic al-Hidāyah remains a central text of Islamic personal law. This English translation, from a Persian version of the work, was prepared by the orientalist Charles Hamilton (c.1752–92) for the East India Company in 1791. Although since superseded, it remains a fascinating document in the history of colonial jurisprudence. The legal system was central to the entrenchment of British rule in India, providing the framework for active control of civil administration and the courts. Translations of Islamic texts were intended to remove the language barrier for colonial officials, and blurred British and native law for the first time. Volume 4 contains sections on the partition of property, the eating of meat, sacrifice, abominations, the cultivation of wasteland, prohibited drinks, hunting, pawning, crimes against the person, fines, wills, and hermaphrodites.
Composed in the twelfth century by the leading Muslim jurist Burhan al-Din al-Marghinani (1135–97), the original Arabic al-Hidāyah remains a central text of Islamic personal law. This English translation, from a Persian version of the work, was prepared by the orientalist Charles Hamilton (c.1752–92) for the East India Company in 1791. Although since superseded, it remains a fascinating document in the history of colonial jurisprudence. The legal system was central to the entrenchment of British rule in India, providing the framework for active control of civil administration and the courts. Translations of Islamic texts were intended to remove the language barrier for colonial officials, and blurred British and native law for the first time. Hamilton's text is one such, and its dedication to Warren Hastings and lengthy preliminary section outline its purpose and composition. Volume 1 contains sections on zakat (alms), marriage, fosterage, divorce, slavery, and vows.
Composed in the twelfth century by the leading Muslim jurist Burhan al-Din al-Marghinani (1135–97), the original Arabic al-Hidāyah remains a central text of Islamic personal law. This English translation, from a Persian version of the work, was prepared by the orientalist Charles Hamilton (c.1752–92) for the East India Company in 1791. Although since superseded, it remains a fascinating document in the history of colonial jurisprudence. The legal system was central to the entrenchment of British rule in India, providing the framework for active control of civil administration and the courts. Translations of Islamic texts were intended to remove the language barrier for colonial officials, and blurred British and native law for the first time. Volume 3 contains sections on agency, claims, laws of business, deposits, loans, gifts, the hiring of slaves, freed slaves, and disputed land sales.
An enormous effort is underway worldwide to attempt to detect gravitational waves. If successful, this will open a new frontier in astronomy. An essential portion of this effort is being carried out in Australia by the Australian Consortium for Interferometric Gravitational Astronomy (ACIGA), with research teams working at the Australia National University, University of Western Australia, and University of Adelaide involving scientists and students representing many more institutions and nations. ACIGA is developing ultrastable high-power continuous-wave lasers for the next generation interferometric gravity wave detectors; researching the problems associated with high optical power in resonant cavities; opening frontiers in advanced interferometry configurations, quantum optics, and signal extraction; and is the world's leader in high-performance vibration isolation and suspension design. ACIGA has also been active in theoretical research and modelling of potential astronomical gravitational wave sources, and in developing data analysis detection algorithms. ACIGA has opened a research facility north of Perth, Western Australia, which will be the culmination of these efforts. This paper briefly reviews ACIGA's research activities and the prospects for gravitational wave astronomy in the southern hemisphere.
Renewable energy can provide a host of benefits to society. In addition to the reduction of carbon dioxide (CO2) emissions, governments have enacted renewable energy (RE) policies to meet a number of objectives including the creation of local environmental and health benefits; facilitation of energy access, particularly for rural areas; advancement of energy security goals by diversifying the portfolio of energy technologies and resources; and improving social and economic development through potential employment opportunities. Energy access and social and economic development have been the primary drivers in developing countries whereas ensuring a secure energy supply and environmental concerns have been most important in developed countries.
An increasing number and variety of RE policies–motivated by a variety of factors–have driven substantial growth of RE technologies in recent years. Government policies have played a crucial role in accelerating the deployment of RE technologies. At the same time, not all RE policies have proven effective and efficient in rapidly or substantially increasing RE deployment. The focus of policies is broadening from a concentration almost entirely on RE electricity to include RE heating and cooling and transportation.
RE policies have promoted an increase in RE capacity installations by helping to overcome various barriers. Barriers specific to RE policymaking (e.g., a lack of information and awareness), to implementation (e.g., a lack of an educated and trained workforce to match developing RE technologies) and to financing (e.g., market failures) may further impede deployment of RE.
Regional anesthesia is a fast-growing field, fuelled by the application of ultrasound technology over the last decade. This book is a technique-oriented guide, which introduces the use of ultrasound technology with practical instruction in the placement of peripheral nerve blocks and continuous perineural catheters. Each procedure is summarized for quick, easy reference, and supplemented by ultrasound images, color photos, and detailed illustrations. Helpful hints and instructions are provided to further optimize block success. Chapters are organized into four sections, focusing on introductory concepts, upper extremity peripheral nerve blocks, lower extremity peripheral nerve blocks and continuous perineural catheters. Written by instructors from a major academic medical center who work in a fast-paced ambulatory setting, this is a key text for residents, fellows and staff physicians who wish to incorporate the use of ultrasound into the scope of their anesthetic practice.