Iron-rich aluminosilicates with disordered structure (laterites) due to the corrosion of kaolinite by iron minerals were investigated as solid precursors for geopolymerization. The particle size ...distribution, B.E.T surface area, thermal activation, and chemical and mineralogical compositions were used to evaluate the reactivity of iron-rich laterites (35wt.% of Fe2O3-FeO). The raw materials in the temperature range between 25 and 500°C showed geopolymerization behaviour similar to that of metakaolin. At temperatures higher than 500°C, the coarsening of particles and the decrease of B.E.T surface area correspond to an initial sintering of laterites explaining the poor polycondensation/geopolymerization and the decrease of strength of the final products. The increase of the temperature of calcination of raw laterites between 25 and 500°C corresponds to a reduction of the setting time of geopolymer products. However, this variation of temperature did not significantly affect the flexural strength that remained between ~4 and ~6MPa, confirming the possibility to produce sustainable matrices, with more energy saving, using highly corroded laterites.
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•Iron-rich aluminosilicate is used for the production of eco-friendly cement.•Unheated and calcined at 500°C samples appeared to have denser structure.•The thermal treatment above 500°C affects the mechanical properties.
Hydroquinone-containing creams cause false increases in capillary glycemia. However, the magnitude of this false increase, and the means to reverse it have not been investigated.
To evaluate the ...technical and clinical impact of hydroquinone-containing creams on capillary glycemia and investigate the efficacy of hand washing and other common practices, in reversing cream effects.
We included 91 participants in a quasi-experimental study in Buea, Cameroon. After determining the hydroquinone content of a cream, Caro Light, we used two glucometers with different enzymatic systems (Accu-Chek Active and OneTouch Ultra 2) to measure fasting glycemia after: initial hand washing (reference), application of 1 ml of hydroquinone-containing cream, finger swabbing with wet gauze, sanitizer application and a series of three hand washings following cream application. Reference glycemia was compared to those obtained after various interventions. Statistical significance was assessed by paired sample t-test, clinical significance by total error allowable (TEa), and clinical impact by Parke's error grid analysis.
The mean differences in capillary glycemia (Intervention-reference) measured by Accu-Chek Active in mg/dl were 28, 27, 38, 16, 4, and -2 after cream application, finger swabbing, sanitizer application, one, two, and three hand washings respectively. Corresponding values for OneTouch Ultra2 were 41, 44, 64, 22, 5 and -5. These differences, except after two and three hand washings were both statistically (p < 0.0001) and clinically significant (TEa). After cream application, Accu-Check had 9.9% of values in Parke's Zones C-E, while OneTouch had 18.7%.
Hydroquinone-containing creams cause significant false increase in capillary glycemia irrespective of the enzymatic system of the glucometer used, and can lead to potentially wrong clinical decisions. A minimum of two hand washings is required prior to capillary glucose measurement.
Abstract
The population properties of intermediate-mass black holes remain largely unknown, and understanding their distribution could provide a missing link in the formation of supermassive black ...holes and galaxies. Gravitational-wave observations can help fill in the gap from stellar mass black holes to supermassive black holes with masses between ∼100–10
4
M
⊙
. In our work, we propose a new method for examining lens populations through lensing statistics of gravitational waves, here focusing on inferring the number density of intermediate-mass black holes through hierarchical Bayesian inference. Simulating ∼200 lensed gravitational-wave signals, we find that existing gravitational-wave observatories at their design sensitivity could either constrain the number density of 10
6
Mpc
−3
within a factor of 10, or place an upper bound of ≲10
4
Mpc
−3
if the true number density is 10
3
Mpc
−3
. More broadly, our method leaves room for incorporation of additional lens populations, providing a general framework for probing the population properties of lenses in the universe.
Abstract Aim This study compared the clinical and biochemical characteristics and microvascular complications found in three groups of type 2 diabetes (T2D) patients: Africans living in Africa; ...African immigrants living in France; and Caucasians living in France. Methods Diagnosed T2D Africans living in Cameroon ( n = 100) were compared with 98 African migrants diagnosed with T2D after having moved to France, and a group of 199 T2D Caucasian patients living in France. All underwent clinical and biochemical evaluations, and all were assessed for microvascular complications. Results The median duration of stay of the migrants in France was 15 years before being diagnosed with diabetes. Despite similar durations of diagnosis, they were 8.9 years younger at the time of diagnosis than Africans living in Cameroon ( P < 0.001). Caucasians and African immigrants in France had lower HbA1c values than Africans in Cameroon ( P < 0.001); they were also more aggressively treated for hypertension and dyslipidaemia and, therefore, had significantly lower blood pressure levels and better lipid profiles. Diabetic nephropathy and retinopathy rates were higher in Cameroon than in the two other groups. After adjusting for age, diabetes duration, HbA1c , hypertension and other covariates, only the prevalence of diabetic nephropathy (OR: 5.61, 95% CI: 2.32–13.53; P < 0.0001) was higher in Cameroon compared with those living in France. Conclusion Our results suggest that Africans who emigrate to France may develop diabetes earlier than those staying in their home country. However, the latter may be a reflection of late diagnosis of diabetes. Also, the less adequate diabetes and hypertension control in the latter would explain their higher rates of nephropathy. Large-scale cohorts are now warranted to substantiate these observations.
There is a paucity of large-scale epidemiological studies on the link between severe hypoglycemia (SH) and corrected QT (QTc) interval prolongation in type 2 diabetes (T2DM).
To evaluate the ...association of SH with QTc prolongation in adults with T2DM.
Prospective cohort analysis of participants enrolled in the ACCORD (Action to Control Cardiovascular Risk in Diabetes) study without QTc prolongation at baseline. SH was assessed over a 24-month period. Incident QTc prolongation was ascertained using follow-up electrocardiograms. Modified Poisson regression was used to generate the risk ratio (RR) and 95% CI for QTc prolongation.
Among 8277 participants (mean age 62.6 years SD 6.5, 38.7% women, 62.8% White), 324 had ≥1 SH episode (3.9%). Over a median of 5 years, 517 individuals developed QTc prolongation (6.3%). Participants with SH had a 66% higher risk of QTc prolongation (RR 1.66, 95% CI 1.16-2.38). The incidence of QTc prolongation was 10.3% (27/261) and 14.3% (9/63) for participants with 1 and ≥2 SH, respectively. Compared with no SH, RRs for patients with 1 and ≥2 SH episodes were 1.57 (95% CI 1.04-2.39) and 2.01 (95% CI 1.07-3.78), respectively. Age modified the association of SH with QTc prolongation (PInteraction = .008). The association remained significant among younger participants (<61.9 years median age: RR 2.63, 95% CI 1.49-4.64), but was nonsignificant among older participants (≥61.9 years: RR 1.37, 95% CI 0.87-2.17).
In a large population with T2DM, SH was associated with an increased risk of QTc prolongation independently of other risk factors such as cardiac autonomic neuropathy. The association was strongest among younger participants.
Epidemiological data on the associations of microvascular disease with atrial fibrillation are scarce. We evaluated the associations of diabetes-related microvascular disease in multiple vascular ...beds and its burden with incident atrial fibrillation among adults with type 2 diabetes.
A total of 7603 participants with type 2 diabetes and without atrial fibrillation were assessed for diabetic kidney disease, retinopathy, or neuropathy at baseline in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study. Incident atrial fibrillation events were adjudicated using follow-up electrocardiograms. Modified Poisson regression was used to generate risk ratios (RRs) and 95% confidence intervals (CIs) for atrial fibrillation.
Of the 7603 participants (mean age 62.5 years, 38.0% women, 63.4% white), 63.3% (n = 4816) had microvascular disease—defined as the presence of ≥1 of: diabetic kidney disease, retinopathy, or neuropathy at baseline. Over a median of 7 years, there were 137 atrial fibrillation events (1.8%). Participants with microvascular disease had a 1.9-fold higher risk of incident atrial fibrillation compared with those without microvascular disease (RR 1.88; 95% CI, 1.20-2.95). Compared with no microvascular disease, the RRs for atrial fibrillation were 1.62 (95% CI, 1.01-2.61) and 2.47 (95% CI, 1.46-4.16) for those with 1 and ≥2 microvascular territories affected, respectively. The RRs for atrial fibrillation by type of microvascular disease were 1.57 (95% CI, 1.09-2.26), 0.95 (95% CI, 0.53-1.70), and 1.67 (95% CI, 1.15-2.44) for neuropathy, retinopathy, and diabetic kidney disease, respectively.
In a large cohort of adults with type 2 diabetes, the presence of microvascular disease and its burden were independently associated with higher risk of incident atrial fibrillation.
Aims
Community‐based data on the association between cardiac autonomic neuropathy (CAN) and incident heart failure (HF) in type 2 diabetes are limited. We evaluated the association of CAN with ...incident HF in adults with type 2 diabetes.
Methods and results
This analysis included participants from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study without HF at baseline. CAN was assessed by electrocardiogram‐based measures of heart rate variability (HRV) and QT interval index (QTI). HRV was measured using standard deviation of all normal‐to‐normal intervals (SDNN) and root mean square of successive differences between normal‐to‐normal intervals (rMSSD). CAN was defined using composite measures of the lowest quartile of SDNN and highest quartiles of QTI and heart rate. Multivariable Cox regression models were used to generate adjusted hazard ratios (aHR) for HF in relation to various CAN measures. A total of 7160 participants (mean age 62.3 standard deviation 6.4 years, 40.8% women, 61.9% white) were included. Over a median follow‐up of 4.9 years (interquartile range 4.0–5.7), 222 participants developed incident HF. After multivariable adjustment for relevant confounders, lower HRV as assessed by SDNN was associated with a higher risk of HF (aHR for the lowest vs highest quartile of SDNN: 1.70, 95% confidence interval CI 1.14–2.54). Participants with CAN (defined as lowest quartile of SDNN and highest quartiles of QTI and heart rate) had a 2.7‐fold greater risk of HF (aHR 2.65, 95% CI 1.57–4.48).
Conclusions
In a large cohort of adults with type 2 diabetes, CAN was independently associated with higher risk of incident HF.
Intradialytic hypotension (IDH), one of the most frequent acute complications of hemodialysis (HD), is associated with increased patient's morbidity and mortality. The aim of this study was to ...determine its prevalence and associated factors among patients on maintenance HD in Cameroon. This was a prospective longitudinal study carried out from June 20, to July 30, 2016 (5 weeks), including adult patients on HD >3 months at a tertiary hospital in Douala. During this period, patients were followed up at each HD session, and their blood pressure and occurrence of clinical events possibly related to IDH were recorded. In this study, IDH was defined as a decrease in systolic BP by >20 mm Hg or a decrease in mean arterial pressure by >10 mm Hg, associated to a clinical event. Logistic regression analysis was used to determine associated factors. We included 104 patients (69 males) with a mean age of 50.74 ± 15.18 years and a median duration on HD of 30.5 (interquartile range: 12.25-58.75) years. Hypertension 99/104 (95.2%) and diabetes 32/104 (30.8%) were the main comorbidities encountered. A total of 1032 HD sessions were followed up with an average of 9.88 ± 1.57 sessions per patient. IDH occurred in 11.6% of HD sessions. Associated factors were age, female sex, HIV infection, feeding during dialysis, and use of antihypertensive drug during or within 2 h before dialysis. The prevalence of IDH in our study was low. Associated factors were mainly related to patient's characteristics and comorbidities.
Aim
We evaluated the associations of heart rate variability (HRV) with incident vision‐threatening retinopathy and retinopathy progression among adults with type 2 diabetes.
Methods
Participants ...recruited to the ACCORD (Action to Control Cardiovascular Risk in Diabetes) study with HRV measures at baseline were analysed. HRV measures included standard deviation of all normal‐to‐normal intervals (SDNN) and root mean square of successive differences between normal‐to‐normal intervals (rMSSD). Low SDNN was defined as SDNN <8.2 ms; low rMSSD as rMSSD <8.0 ms. We used multivariable adjusted Cox proportional hazards and modified Poisson regression models to generate risk estimates for incident vision‐threatening retinopathy and retinopathy progression, respectively.
Results
A total of 5810 participants without incident vision‐threatening retinopathy at baseline (mean age 62 years, 40.5% women, 63.5% White) were included. Over a median of 4.7 years, 280 incident vision‐threatening retinopathy cases requiring treatment occurred. Low HRV (vs. normal HRV) was associated with higher risk of incident vision‐threatening retinopathy (adjusted hazard ratio 1.32 95%CI 1.03–1.71 and 1.14 95%CI 1.01–1.28 for low SDNN and rMSSD, respectively). In the subset of 2184 participants with complete eye examinations at baseline and 4 years, 191 experienced retinopathy progression, and low HRV (vs. normal HRV) was associated with a higher risk of retinopathy progression (adjusted relative risks 1.36 95%CI 1.01–1.83 and 1.36 95%CI 1.01–1.84 for low SDNN and rMSSD, respectively).
Conclusions
Cardiac autonomic neuropathy, as assessed by low HRV, was independently associated with increased risks of incident vision‐threatening retinopathy and overall retinopathy progression in a large cohort of adults with type 2 diabetes.
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