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The cerite supergroup is established and includes the cerite group (silicates) and merrillite group (phosphates). Cerite-group minerals are cerite-(Ce), ferricerite-(La), aluminocerite-(Ce) and taipingite-(Ce). The merrillite group is subdivided into two subgroups: merrillite (merrillite, ferromerrillite, keplerite and matyhite) and whitlockite (whitlockite, strontiowhitlockite, wopmayite and hedegaardite). Cerite-(La) has been renamed ferricerite-(La). The new nomenclature has been approved by the International Mineralogical Association Commission on New Minerals, Nomenclature and Classification.
Stroke is a major contributor to mortality, disability and long-term use of healthcare services. As for all chrono-dependant conditions, clinical results are associated with timely access to appropriate care. Thrombectomy (EVT) is an effective treatment for large vessel occlusions, but can only be provided in highly-specialized centers by experienced personnel. We sought to develop a framework to aid decision-making on the appropriateness of opening new EVT centers in Québec, Canada.
Data sources included provincial administrative healthcare databases, population density statistics, field evaluation of Québec's four existing EVT care networks, and literature review concerning structural and performance criteria for EVT centers. We consulted EVT clinical teams, interdisciplinary stroke experts, patients, professional association representatives, healthcare managers and decision-makers.
Access to EVT is suboptimal in all 17 regions of Québec, with virtually no access in remote areas. Results of key performance indicators indicated favorable treatment delays after arrival at the EVT center. However, door-to-needle and door-in-door-out times were long for patients transferred from non-EVT centers. High use of ambulances indicated the potential to transport patients to the most appropriate center. In light of ‘real world’ results and other sources of information, the need for a new EVT center should consider the following criteria: sub-optimal EVT access within the region; transport time to an existing EVT center >1 hour; expected patient volume within 2 hours of transport; impact on volume of existing programs; availability of long-term financial support; availability of a critical mass of neurointerventionists, vascular neurologists, and neurosurgeons; demonstrated quality of stroke care; and, presence of a stroke unit.
The triangulation of literature, clinician experience and the Québec context enriched the evaluation process. Furthermore, this facilitated the development of a framework that was broadly applicable across regions to the real-world setting of decision-making in a complex system of care.
This study examined the mediating role of romantic perfectionism in the associations linking romantic attachment insecurity and self-perceived dyadic coping in a community sample of 170 mixed-sex couples. Path analyses, based on the actor-partner interdependence model, revealed that other-oriented perfectionism in men and women mediated the link between their own attachment-related avoidance and dyadic coping. Other-oriented perfectionism in women mediated the link between their own attachment-related anxiety and dyadic coping. Findings contribute to advancing knowledge about the intrapersonal and interpersonal mechanisms underlying coping processes in couples. Results also inform clinical interventions targeting attachment insecurities and perfectionism in the context of romantic relationships.
Decision-making about replacement or modification of an implantable cardioverter defibrillator (ICD) must be patient-centered and clinically appropriate. We engaged both patients and health care professionals in a multi-method approach in order to recommend structures and processes that facilitate informed and shared decision-making.
A systematic literature review (2000 to 2017) was performed focusing on the patient's perspective and the optimal organization of structures and processes for decision-making. A province-wide field evaluation based on medical chart review was carried out to provide ‘real world’ evidence in Québec's six ICD implanting centers (1 July to 31 December, 2016; N = 418). Patients and health care professionals reviewed the findings of the review and field evaluation, and deliberated recommendations in an anonymous manner by electronic mail. A joint meeting focused on proposed recommendations concerning shared decision-making.
The patients provided feedback on the literature review based on their ICD experience, and highlighted the need for better and more interactive decision aids, clinical information and time, and a private space for sensitive discussions. The field evaluation underlined the variability of treatment choices at the time of replacement and that more than one in ten patients had undergone ICD deactivation. Proposed recommendations focus on multi-disciplinary, integrated follow-up of patients and outline best practice for incorporating patient wishes and life objectives when discussing treatment options. The multi-round consultation process allowed both patients and professionals to co-construct recommendations with our evaluation team.
This multi-method approach enriched our interpretation of literature and ‘real world’ data and facilitated identification and prioritization of important themes. Partnership with both patients and clinicians added a new and energizing dynamic to our evaluation and recommendation processes. We acknowledge the contribution of the members of the patient committee and the clinical experts committee.
One important objective at the Institut d'excellence en santé et en services sociaux (INESSS) is to guide the implementation of promising new technologies into Québec's healthcare system. A comprehensive evaluation framework was recently developed that takes into account the dynamic and iterative nature of the life cycle of such technologies. This framework is presently being used to inform the decision-making process concerning use of thrombectomy for ischemic stroke.
A field evaluation has been undertaken since April 2016 in all four of Québec's specialized tertiary stroke centers. This real-world evidence is communicated regularly to the clinical teams as well as decision-makers. A systematic literature surveillance is also ongoing, with results being shared amongst clinical experts on our interdisciplinary advisory committee. On the basis of the generated evidence from these sources, recommendations to optimize structures, processes of care and clinical outcomes will be developed, in collaboration with the interdisciplinary committee.
Thrombectomy has been shown to be safe and effective for treating ischemic stroke in the randomized trial setting in high-volume, expert centers. Real-world evidence from Québec indicates increasing use of this new technology but with wide variation across health regions. Observed times to treatment appear favorable for patients admitted directly to tertiary centers, but inter-hospital transfer is associated with important increases in delays from first door to thrombectomy. The documentation of 90-day outcomes is problematic, especially for patients transferred out of tertiary stroke centers prior to discharge. Uncertainties raised in the literature include patient selection criteria and optimal processes of care during prehospital and inter-hospital phases of the patient's trajectory.
The ongoing comprehensive evaluation of thrombectomy for ischemic stroke in Québec is a concrete example of how the use of an innovative, disruptive technology can be optimized. We acknowledge the contribution of the members of the clinical expert committee.
The use of transcatheter aortic valve implantation (TAVI) is evolving. Our Cardiovascular Evaluation Unit is implementing a comprehensive approach to inform decision-makers on optimal use of TAVI, including the development of quality standards. We are implementing a multifaceted evaluation framework in collaboration with clinical stakeholders.
Our unit has carried out a continuous field evaluation in collaboration with the clinical teams at all six TAVI centers in Québec for the past four years (1 April 2013–31 March 2017), with regular feedback to the teams and sharing of results with each individual center. Hospital documentation was reviewed according to established national quality indicator definitions. Field evaluation data were combined with the results of systematic literature review to establish provincial standards for practice, through a deliberation process by an interdisciplinary committee of clinical experts from each center. Systematic surveillance of the literature is ongoing.
In the period 2013–2017, use of TAVI in Québec was limited to very elderly patients with significant comorbidities at high risk of operative mortality. We observed improvements in both processes of care (e.g. documentation of risk scores) and clinical outcomes (e.g. 30-day and 1-year mortality) over time. Our consensus standards recognize the potential value of TAVI for patients at moderate operative risk, identify uncertainties and recommend best practices for patient evaluation and clinical decision-making about choice of treatment.
A comprehensive, long-term evaluation process of TAVI with feedback to centers is associated with improvements in processes of care and outcomes. In the present context of expanding clinical indications, we will continue to evaluate patient selection, processes and outcomes according to the newly-established provincial quality standards. This iterative approach facilitates continued evidence generation and decision-making for optimal use of an evolving intervention. We acknowledge the contribution of the members of the expert clinical committee.
Our cardiovascular evaluation unit is mandated to evaluate transcatheter aortic valve implantation (TAVI) in the province of Québec. In 2012, it was recommended that only patients at too high risk for surgery receive TAVI. In partnership with our six hospital TAVI programs, we have measured indicators of structure, process and outcomes since 2013. We are collaborating with multidisciplinary clinical experts to update recommendations for optimal use. Herein, we present the evolving portrait of TAVI in Québec and identify priority issues.
Clinical data were collected and analyzed for all TAVI performed from 1 April 2013 to 31 March 2016. Regular site feedback was provided. A systematic review of recent guidelines and randomized trials facilitated the interpretation of “real world” results and formulation of provincial quality standards.
Provincial TAVI volume increased from 294 in 2013–14 to 340 in 2014–15, and to 360 in 2015–16. Patient age and sex distribution remained relatively constant over time (median age 83 years; 47 percent female). However, the median predicted risk of operative mortality (STS score) decreased in the latest period [6 percent (Interquartile Range, IQR: 4–9) versus 7 percent (IQR: 4–9) versus 4 percent (IQR: 3–7)], suggesting TAVI is increasingly being performed in lower-risk patients. Clinical documentation and processes of care generally improved. Thirty-day mortality decreased (6.1 percent versus 4.1 percent versus 2.8 percent). The literature review identified two central issues: TAVI futility in patients who are too sick and apparent non-inferiority of TAVI compared with surgical valve replacement in medium-risk patients.
Our province-wide TAVI evaluation indicates improving processes and outcomes. Patient selection remains the key in our universal healthcare system, with the need to minimize futile and costly therapy and offer TAVI to those most likely to benefit. Continued monitoring of clinical practice and newly-established quality standards, in close collaboration with clinical teams, remains essential to promote optimal use of this evolving technology.
In the past decade numerous efforts have been made to enhance quality of care in the province of Québec for patients with ST-elevation myocardial infarction (STEMI). Despite two prior field evaluations and diffusion of a systematic review as well as recommendations, a third audit revealed persistent gaps in care, specifically excessive treatment delays. Our cardiovascular evaluation unit thus aimed to develop a more comprehensive quality improvement framework that further engaged healthcare professionals.
A literature update identified best practices and ways to reduce treatment delays and improve outcomes. This review, combined with the latest evaluation results, was used to establish structural and process quality standards adapted to the Québec context, via a consensus process with a panel of clinical experts. The standards identified quality-of-care targets and key elements of a governance structure to guide the improvement process. Quality indicators to monitor change were also developed. An implementation plan was then created, likewise based on literature and evaluation results.
For the first time, the unit publicly disseminated the results of the third evaluation according to region, in addition to standard individual hospital “report cards”. A summit conference was held during which the standards and indicators were presented to clinicians and other stakeholders, in collaboration with the health ministry and a panel of cardiovascular experts. Site visits are planned to facilitate change and establishment of local improvement plans and committees. A “tool kit” was developed containing a treatment algorithm, a drug protocol, five quality indicators each for processes and care networks, and measurement tools for indicators. A 75 percent minimal achievement target was set for treatment times.
A comprehensive framework aimed at improving quality of care for STEMI patients and monitoring change was created by combining evidence from the literature and “real world” data and mobilizing key stakeholders.
We have previously shown that curcumin (CUR) may increase lipid accumulation in cultured human acute monocytic leukaemia cell line THP-1 monocytes/macrophages, but that tetrahydrocurcumin (THC), an in vivo metabolite of CUR, has no such effect. In the present study, we hypothesised that the different cellular uptake and/or metabolism of CUR and THC might be a possible explanation for the previously observed differences in their effects on lipid accumulation in THP-1 monocytes/macrophages. Chromatography with tandem MS revealed that CUR was readily taken up by THP-1 monocytes/macrophages and slowly metabolised to hexahydrocurcumin sulphate. By contrast, the uptake of THC was low. In parallel with CUR uptake, increased lipid uptake was observed in THP-1 macrophages but not with the uptake of THC or another CUR metabolite and structurally related compounds. From these results, it is possible to deduce that CUR and THC are taken up and metabolised differently in THP-1 cells, which determine their biological activity. The remarkable differential cellular uptake of CUR, relative to THC and other similar molecules, may imply that the CUR uptake into cells may occur via a transporter.
Showerhead cooling process which consists of internal convective cooling and external
film cooling of a turbine blade is investigated using ANSYS-CFX software. The aim of the
present investigation is to provide a better understanding of the fundamental nature of
showerhead cooling using the three dimensional Reynolds averaged Navier Stokes analysis. A
numerical model has been developed to study the effects of coupled internal and external
cooling of the leading edge for a semi-elliptical body shape with the SST k-ω model. This model
consists of all internal flow passages and cooling hole rows at the leading edge. The
numerical results obtained are discussed and compared with experimental data available in
the literature. The results show that the cooling efficiency increases with the increase
of the blowing ratio and the Mach number, therefore, the overall efficiency for the steel
becomes less important compared to the plexiglas which has a low thermal conductivity.
Influenza A (H1N1) viruses when initially isolated in mammalian cell cultures (MDCK cells) had different agglutination reactions with chicken and guinea-pig erythrocytes compared to the same viruses after passage. On first isolation the virus HA resembled the ‘O’ phase viruses described originally by Burnet and Bull and agglutinated mammalian but not avian erythrocytes. After passage, the virus HA resembled a classical ‘D’ phase virus and agglutinated both avian and mammalian erythrocytes. Monoclonal and polyclonal antisera detected antigenic differences between the HAs of the viruses in the ‘O’ and ‘D’ phases. The ‘O’ phase virus HA reacted preferentially with antibodies in post infection human antisera. Viruses in the ‘O’ phase replicated poorly in the allantoic cavity of embryonated hens' eggs whilst ‘D’ phase virus replicated in both MDCK cells and in embryonated hens' eggs. At least three distinguishable subpopulations of influenza A (H1N1) viruses may co-exist in clinical throat swab material, including viruses possessing HAs in the ‘O’ and ‘D’ phases and other ‘D’ phase viruses cultivable in embryonated hens' eggs but antigenically distinguishable from the corresponding ‘D’ phase virus in MDCK cells.
During an outbreak of parvovirus B19 infection among four related families at least 70% of the household contacts, including a woman at the 33rd week of pregnancy, became infected. Twins were born at the 39th week of pregnancy, both with B19 infection. B19 DNA was detected in their sera by a nested PCR, anti-B19 IgM was detectable only by an immunofluorescence assay, and low levels of maternal anti-B19 IgG were demonstrable by an immunoenzymatic test in the serum of both children. All the haematological parameters were normal at birth and 6 months later, when B19 DNA and anti-B19 antibody were no longer detectable in serum samples. This observation emphasizes the high risk of B19 infection among household contacts and the possibility of a favourable outcome of the foetal infection, possibly related to infection late in the pregnancy.
The thermodynamic efficiency of the Brayton cycle, upon which all gas turbines (aeropropulsion and power generation) are based on scales with the peak operating temperature. However, the peak temperature is limited by the turbine blades and the temperature they can withstand. The highest temperatures in the gas turbine occur in the combustor region but these temperatures are often too high for turbine blades. As a result, the combustion products must be diluted with relatively cooler air from the compressor to reduce the temperature to tolerable levels for the turbine blades. This research suggests placing a ring of high temperature open cell metal foam between the combustors and turbine sections of the jet engine to mix and average the difference in temperatures resulting from the cooling schemes in combustor cans. Temperature mixing effect was tested using a special setup with the application of an infrared camera and streams of hot and cold air passing through the foam. High speed flow pressure drop around Mach 1 (340 m/s) was done on the same foam samples to understand pressure drop in the compressible regime of air. Infrared imaging showed that open cell metal foams successfully mixed and averaged the difference in temperatures of the hot and cold gasses thus creating a more uniform temperature profile while pressure drop testing revealed that open cell metal foams result in minimal pressure drop at high flows especially when the increase in temperature in taken into consideration.
The effect of methionine ethyl ester (MetOC2H5), a non-toxic compound on the corrosion
of iron in citric-chloride solution at pH = 5, has been investigated by various corrosion
monitoring techniques. Results obtained reveal that this compound is a very good inhibitor.
Potentiodynamic polarization studies show that MetOC2H5 is a mixed-type inhibitor
and that it acts on the cathodic reaction without changing the mechanism of hydrogen
evolution. Variation in impedance parameters (Rt and Cdl) are indicative
of adsorption of MetOC2H5 on the metal surface. The adsorption of this product on the
iron surface obeys a Temkin adsorption isotherm. The effect of temperature indicates
that inhibition efficiency of MetOC2H5 slightly changes with increasing temperature
in the range of 30-60 °C.
Over a century after its gestation in the slums of Buenos Aires and Montevideo, the tango has become a global music in several interdependent ways. It is global in the most literal sense of geographic reach, flourishing in Buenos Aires and Tokyo, in Saigon and Durban, in small towns in Scandinavia and in the U.S. It has attained and maintained such a reach through its distinctive and enduring musical profile and, more importantly, through several kinds of semantic flexibility. The tango bears strong yet mutable links to place and culture; it is variously but vividly perceived as belonging to the Rio de la Plata culture of the Argentine and Uruguayan capitals, as the national music of Argentina, as more generically Latin, or just as pleasantly (or bizarrely) exotic, older dance music. It rewards the intense attention offered by aficionados in Buenos Aires, by a core of tango kichigai (tango fanatics) in Japan, and by serious devotees elsewhere, in addition to the passing notice of people exposed only to isolated dances in movies or at an ice-skating rink. For different populations, the tango is either a historical footnote, a healthful hobby, or a stunningly complex and all-consuming focus for emotional life.
This article analyses how, in the last half-century, scholars have differed over the nature of Italian foreign policy under the fascist regime. It examines the debate between orthodox and revisionist historians over Mussolini's foreign policy in general, and also over three specific areas of Italian policy in the interwar years: Franco-Italian relations, Italian participation in the Spanish Civil War, and the alliance with nazi Germany. The author concludes that much of the debate has arisen because of conceptual befuddlement; writers have been primarily concerned with questions of coherence and continuity, and not with understanding Italian foreign relations. Historians have also disagreed over whether Mussolini had a ‘programme’, but a closer look shows that many of them were engaging in a semantic debate, and did not differ over the nature of fascist policy.
14C apparent ages along with δ13C values for three different fractions of humic matter (HM) isolated from a suite of four paleosols (PAs) interbedded within tephra are reported. The dated HM fractions were: 1) HA, the easily released humic acids; 2) HAtot, the bulk of humic acids; 3) RES, the insoluble HM. The 14C sequence dated from 13,000–25,000 BP, in agreement with stratigraphy and previous data. Age differences up to 2540±430 were statistically significant among fractions; their order of magnitude being independent from C content and depth. All the PAs showed a common pattern of among-fraction age variation, 14C aging trending from RES to HAtot through HA. As the HM fractions exhibited quite comparable δ13C values (δ13C = −25.4±0.2), it is inferred that the primitive organic matter (OM) input to PAs was dominantly supplied by vegetation of C-3 photosynthetic pathway which underwent complete decomposition during diagenesis.