To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
This research aims to characterize the mineralogical and crystal-chemical purity of two samples of natural talc (BTT6, BTT7) from the occurrence ‘Ecole1’ in the deposit of Minzanzala, southwest Gabon. X-ray diffraction and modal-composition calculations demonstrated the presence of quartz and Al–Fe-bearing phases (kaolinite and/or chlorite and/or Al–Fe oxyhydroxides) as accessory minerals in both ores. In contrast, the chemical and spectroscopic characterization of the talc component revealed remarkable chemical purity expressed by very low Fe contents. According to these results, the talc of Minzanzala might be used as a filler in a wide range of industrial applications, such as in cosmetics, paints, polymers or ceramics.
Low and middle-income countries (LMICs) bear a disproportionately high burden of sepsis, contributing to an estimated 90% of global sepsis-related deaths. Critical care capabilities needed for septic patients, such as continuous vital sign monitoring, are often unavailable in LMICs.
This study aimed to assess the feasibility and accuracy of using a small wireless, wearable biosensor device linked to a smartphone, and a cloud analytics platform for continuous vital sign monitoring in emergency department (ED) patients with suspected sepsis in Rwanda.
This was a prospective observational study of adult and pediatric patients (≥ 2 months) with suspected sepsis presenting to Kigali University Teaching Hospital ED. Biosensor devices were applied to patients’ chest walls and continuously recorded vital signs (including heart rate and respiratory rate) for the duration of their ED course. These vital signs were compared to intermittent, manually-collected vital signs performed by a research nurse every 6-8 hours. Pearson’s correlation coefficients were calculated over the study population to determine the correlation between the vital signs obtained from the biosensor device and those collected manually.
42 patients (20 adults, 22 children) were enrolled. Mean duration of monitoring with the biosensor device was 34.4 hours. Biosensor and manual vital signs were strongly correlated for heart rate (r=0.87, p<0.001) and respiratory rate (r=0.74 p<0.001). Feasibility issues occurred in 9/42 (21%) patients, although were minor and included biosensor falling off (4.8%), technical/connectivity problems (7.1%), removal by a physician (2.4%), removal for a procedure (2.4%), and patient/parent desire to remove the device (4.8%).
Wearable biosensor devices can be feasibly implemented and provide accurate continuous vital sign measurements in critically ill pediatric and adult patients with suspected sepsis in a resource-limited setting. Further prospective studies evaluating the impact of biosensor devices on improving clinical outcomes for septic patients are needed.
Patients suffering from an out-of-hospital cardiac arrest (OHCA) associated with an initial shockable rhythm have a better prognosis than their counterparts. The implications of recurrent or refractory malignant arrhythmia in such context remain unclear. The objective of this study is to evaluate the association between the number of prehospital shocks delivered and survival to hospital discharge among patients in OHCA.
This cohort study included adult patients with an initial shockable rhythm over a 5-year period from a registry of OHCA in Montreal, Canada. The relationship between the number of prehospital shocks delivered and survival to discharge was described using dynamic probabilities. The association between the number of prehospital shocks delivered and survival to discharge was assessed using multivariable logistic regression.
A total of 1,788 patients (78% male with a mean age of 64 years) were included in this analysis, of whom 536 (30%) received treatments from an advanced care paramedic. A third of the cohort (583 patients, 33%) survived to hospital discharge. The probability of survival was highest with the first shock (33% [95% confidence interval 30%-35%]), but decreased to 8% (95% confidence interval 4%-13%) following nine shocks. A higher number of prehospital shocks was independently associated with lower odds of survival (adjusted odds ratio=0.88 [95% confidence interval 0.85-0.92], p < 0.001).
Survival remains possible even after a high number of shocks for patients suffering from an OHCA with an initial shockable rhythm. However, requiring more shocks is independently associated with worse survival.
Studies interested in Indigenous voting in Canada tend to focus on socio-economic, cultural and political factors that explain their lower levels of electoral participation. While highly relevant given Canada's ongoing reality as a settler-colonial state, these studies are of limited help in making sense of recent increases in electoral engagement in Indigenous communities across the country. Using data from four elections between 2006 and 2015, this study focuses instead on why some Indigenous individuals vote and how they vote. Our analysis suggests that one of many possible reasons for the recent surge in Indigenous turnout has to do with the candidates presenting themselves for elections. Higher voter turnout in Indigenous communities corresponds with a higher proportion of Indigenous candidates. This trend is consistent with the literature on affinity voting. We also find that political parties who present an Indigenous candidate receive more votes in constituencies with a high proportion of Indigenous voters.
This work presents the synthesis of minerals with a layered structure in supercritical water/ethanol mixtures to decrease the critical coordinates of the solvent regarding water. Depending on the water/ethanol ratio of the solvent, we obtained three different minerals adopting an octahedral brucitic sheet: (1) without a Si-tetrahedral sheet (O); (2) associated with one Si-tetrahedral sheet (T-O); or (3) intercalated between two Si-tetrahedral sheets (T-O-T). We have thus shown that ethanol in a supercritical water/ethanol mixture changes the solubility of silicon with a direct consequence on the formation of the tetrahedral silicon sheets and thus makes it possible to control the structure of the synthesized layered material.
Healthcare organizations should assess the relevance of both existing and new practices. Involving patients in decisions regarding which health technologies and interventions should be prioritized could favor a better fit between strategic choices and patients needs.
Following a systematic review of existing multi-criteria decision support tools and a consultation with hospital clinicians and managers, a set of potentially relevant criteria was identified. A three-round modified Delphi study was then conducted among four groups (hospital managers, heads of department, clinicians, and patient representatives) in order to reach consensus on criteria that should be considered in the tool.
In total, seventy-four participants completed the third round of the Delphi study. Consensus was obtained on twelve criteria. There were some significant differences between groups in priority scores given to criteria. Patient representatives differed significantly from other groups on two criteria. Their ranking of the accessibility criteria was higher, and their ranking of the organizational aspect criteria was lower than for the other groups.
Patient representatives can be involved in the development of a multi-criteria decision support tool to identify, evaluate and prioritize high value-added health technologies and interventions in order to enhancing clinical appropriateness The fact that accessibility aspects were more important for patient representatives calls for specific attention to these criteria when prioritizing health technologies or interventions. Furthermore, we need to ensure that the decisions made regarding the relevance of these technologies and interventions also reflect patients’ preferences.
Despite numerous medical, pharmacological and surgical approaches for chronic low back pain (LBP), many patients continue to complain of severe disabling pain. Peripheral nerve field stimulation (PNfS), alone or combined with spinal cord stimulation, is a neuromodulation procedure that have been recently developed and implemented in our hospital. We conducted a Health Technology Assessment (HTA) to determine if PNfS may be considered as a standard of practice in the management of intractable LBP and failed back surgery syndrome (FBSS).
An interdisciplinary group of experts was involved in the project. A systematic review (SR) was performed in several databases and grey literature to identify clinical practice guidelines, SR and observational studies published through September 2016. A survey was conducted among other chronic pain centers in Canada to document PNfS use in LBP and FBSS treatment.
Data on effectiveness and safety of PNfS in chronic LBP treatment were scarce. Short-term results (3-12 months) from small sample and low quality studies suggest that PNfS, alone or combined with spinal cord stimulation, is associated with pain intensity and opioid use reductions. Effects on functional status and quality of life remain undetermined. Most frequent adverse events reported with PNfS devices are lead migrations, discomfort or pain and surgical site infections. No other Canadian pain centers were found to use PNfS in chronic LBP or FBSS.
PNfS is potentially a beneficial treatment option for patients with chronic low back pain or FBSS. However, the value of this innovative treatment remains unknown. Among factors to be clarified are target population (any chronic low back pain or FBSS), use of PNfS alone or combined with spinal cord stimulation, long-term effects, and comparison with conventional medical management. PNfS use in chronic LBP has to be assessed through a rigorous framework before its introduction as a standard medical practice.
Glyphosate-resistant populations of Conyza canadensis have been spreading at a rapid rate in Ontario, Canada, since first being documented in 2010. Determining the genetic relationship among existing Ontario populations is necessary to understand the spread and selection of the resistant biotypes. The objectives of this study were to: (1) characterize the genetic variation of C. canadensis accessions from the province of Ontario using simple sequence repeat (SSR) markers and (2) investigate the molecular mechanism (s) conferring resistance in these accessions. Ninety-eight C. canadensis accessions were genotyped using 8 SSR markers. Germinable accessions were challenged with glyphosate to determine their dose response, and the sequences of 5-enolpyruvylshikimate-3-phosphate synthase genes 1 and 2 were obtained. Results indicate that a majority of glyphosate-resistant accessions from Ontario possessed a proline to serine substitution at position 106, which has previously been reported to confer glyphosate resistance in other crop and weed species. Accessions possessing this substitution demonstrated notably higher levels of resistance than non–target site resistant (NTSR) accessions from within or outside the growing region and were observed to form a subpopulation genetically distinct from geographically proximate glyphosate-susceptible and NTSR accessions. Although it is unclear whether other non–target site resistance mechanisms are contributing to the levels of resistance observed in target-site resistant accessions, these results indicate that, at a minimum, selection for Pro-106-Ser has occurred in addition to selection for non–target site resistance and has significantly enhanced the levels of resistance to glyphosate in C. canadensis accessions from Ontario.
In this investigation the factor structure of the Adult Attachment Interview was studied in a partially at-risk sample of 120 young adults. More specifically, 60 participants had engaged in nonsuicidal self-injury (NSSI; 53 females, M age = 20.38 years), and 60 were non-self-injuring controls matched by age and sex. Theoretically anticipated differential associations between preoccupied (but not dismissing) states of mind and NSSI were then examined. Exploratory factor analyses identified evidence for two weakly correlated state of mind dimensions (i.e., dismissing and preoccupied) consistently identified in factor analyses of normative-risk samples. As hypothesized, results further showed that preoccupied (but not dismissing) states of mind were associated with NSSI behavior. Findings support existing arguments suggesting that the regulatory strategy adults adopt when discussing attachment-related experiences with primary caregivers, particularly passive, angry, or unresolved discourse patterns, is uniquely correlated with NSSI.
Time-domain reflectometry (TDR) is widely used in soil physics to determine water content. Existing equipment and methods ran be adapted to measurements of snow wetness. The main advantages compared to other methods are flexibility in constructing sensors, minimal influence on snow cover during measurements and sensors can be multiplexed. We developed sensors suitable for continuous and non-continuous measurements of snow wetness and density, measured the apparent permittivity in different snow densities and snow types, and compared the measurements to existing mixing formulas for mixtures of snow and air. In dry snow, density was measured from 110 to 470 kg m−3. The residual error is 14 kg m −3 and the 95% confidence interval of our model is 3 kg m−3. To measure snow density and wetness continuously suitable sensors have been constructed. Their small size and high surface area to weight ratio minimizes their movement in the snowpack, except when they are exposed to intense solar radiation. Results show that changes in dry-snow density of less than 5 kgm−3 can be detected. Infiltration of even small amounts of water clearly shows up in the permittivity. At the surface of the snowpack, problems occur due to the formation of air pockets around the sensors during long-term measurements.
We constructed an automated system to transform organic samples to CO2, which included several options such as: combustion in 2 steps with collection of the 2 fractions, volatile fraction combustion, and 13C sampling. The process includes organic matter combustion, CO2 drying, quantification of the mass of carbon, CO2 collection in a glass vial, and eventually 13C sampling. The system is computer-controlled and -monitored. The apparent background age of the automated system reaches 0.191 ± 0.011 pMC (2 σ), equivalent to a 14C age of about 51,700 yr BP, and requires only 30 min of handling, instead of the several days needed when using a manual procedure.
We report the detection and analysis of several molecules arising from the WR nebula NGC 2359 around the WN4 star WR 7 (HD 56925). We have detected 3mm and 1mm rotational lines from 13CO, C18O, HCO+, CS, CN and HCN, and determined lower limits for the SiO. The survey was performed in the southeastern part of the optical nebula, where we previously inferred the presence of dense (104 cm–3) material.
We show CO and 13CO maps toward the WR nebulae NGC 2359, NGC 6888 and Anon (WR 134). We determine global parameters and discuss the probable origin of this gas. Nowadays it is becoming clear that molecule formation and survival is be possible around massive evolved stars.
We started a program of identification of faint structures in PNe on HST archive images, based on the “à trous” wavelet transform (Starck et al. 1998). Using this technique, an image is decomposed in a new set of N images, each with the same number of pixels as the original one, but containing only the structures of a characteristic scale size (going from one image to the next, the characteristic scale vary by a factor of two). The original image c0 can be expressed as the sum of all wavelet scales plus a residual smoothed array cN by C0(x, y) = CN(x, y) + Σj=1Nwj(x, y).