Accuracy of five algorithms to diagnose gambiense human African trypanosomiasis.

Algorithms to diagnose gambiense human African trypanosomiasis (HAT, sleeping sickness) are often complex due to the unsatisfactory sensitivity and/or specificity of available tests, and typically include a screening (serological), confirmation (parasitological) and staging component. There is insufficient evidence on the relative accuracy of these algorithms. This paper presents estimates of the accuracy of five algorithms used by past Médecins Sans Frontières programmes in the Republic of Congo, Southern Sudan and Uganda

Synthesis and Characterization of High-Iron Alite-Calcium Sulfoaluminate-Ferrite Cements Produced from Industrial By-Products

Ordinary Portland cement (OPC) and calcium sulfoaluminate cement (CSAC) are well-known and commonly used construction materials. The clinker phases mainly responsible for their strength development are C3S (alite) in OPC, which hydrates to form a calcium silicate gel phase; and C4A3S ´ (calcium sulfoaluminate) in CSAC, which hydrates to rapidly form ettringite. The purpose of this work was to produce high-iron alite-calcium sulfoaluminate-ferrite cements, by combining C4AF (ferrite), from 5% to 50% by weight, to the C3S and C4A3S ´ clinker phases. Producing this alite-calcium sulfoaluminate-ferrite cement would decrease the requirement of bauxite in the raw materials, which would consequently reduce its cost. The use of industrial by-products would also reduce the CO2 emissions and the firing temperature by 200–250uC compared with OPC. This article presents the synthesis and characterization of five compositions produced from industrial by-products (hydrated lime related to carbide lime, fly ash, slag, and red mud) and bauxite, formulated as follows: C3S from 20% to 50%, C2S from 10% to 20%, C4A3S ´ from 10% to 20%, C4AF from 5% to 50%, and CS ´ from 4% to 6% by weight. The clinker with the lowest ferrite content required a higher firing temperature (1275uC) than the compositions with high ferrite contents (1250uC). Impurities, such as MgO and TiO2, introduced by the industrial by-products affected the mineralogical compositions. Consequently, some adjustments of the raw mix were necessary to obtain the desired clinker compositions

Protection personnelle antivectorielle

Les vecteurs des agents du paludisme ou de la leishmaniose, rencontrés lors de voyages dans les régions à climat chaud, s'ajoutant à la transmission par le moustique tigre (Aedes albopictus) des virus chikungunya et de la dengue dans le sud de la France, ont montré l'intérêt d'une réflexion approfondie sur la protection personnelle antivectorielle. En cas d'épidémie, nos concitoyens se protègent individuellement en se procurant sur le marché tout un arsenal de moyens où le meilleur côtoie le pire. Pour donner à chacun des informations sur l'efficacité et l'innocuité de ces moyens de protection, la Société de médecine des voyages et la Société française de parasitologie ont initié cette étude qui a pris la forme de « Recommandations de bonne pratique », en suivant le schéma élaboré par la Haute Autorité de santé. Cet ouvrage rassemble ainsi toutes les données pertinentes, validées et mises en forme pour être utilisées non seulement par les personnels de santé (médecins, pharmaciens, infirmiers), mais aussi par les agents touristiques ainsi que par les particuliers pour se protéger des nuisances et des maladies à vecteurs qui constituent de préoccupants problèmes de santé publique

Coal Ash By-Product from Shanxi Province, China, for the Production of Portland–Calcium Sulfoaluminate

Twenty bulk samples were collected from ponded coal combustion ash in Shanxi Province, China, as part of an investigation of their beneficiation potential. The samples were shipped to the University of Kentucky, where they were chemically analyzed. The samples were highly consistent in chemistry, falling within the ASTM C-618 class F compositional range. The particle size of the ponded ash was relatively coarse, with only ,7% by weight on average, falling below 200 mesh (75 mm) particle size. The bulk of the material (.80%) was within 50 by 200 mesh (equivalent to 300 by 75 mm). X-ray diffraction investigation combined with microscopy indicated that the agglomeration was probably due to the presence of small amounts (i.e., ,3.5%) of gypsum. The utilization potential of the ash was assessed in light of its characteristics and location. The presence of sulfate and relatively high alumina concentration, which averaged ,37%, suggested that it may serve as an important ingredient in the fabrication of a Portland–calcium sulfoaluminate (CSA) hybrid cement. Portland-CSA hybrid clinkers were successfully produced from this ponded ash when mixed with hydrated lime, gypsum, fluorite, and bauxite. The raw mixture was fired at 1250uC for 60 minutes twice (sample D) and consisted of approximately 40% alite (C3S), 21% belite (C2S), 3% ferrite (brownmillerite or C4AF), 32% CSA (ye’elimite, Klein’s compound, or C4A3SO3), and no free lime by weight

Behavior and Impact of Zirconium in the Soil–Plant System: Plant Uptake and Phytotoxicity

Because of the large number of sites they pollute, toxic metals that contaminate terrestrial ecosystems are increasingly of environmental and sanitary concern (Uzu et al. 2010, 2011; Shahid et al. 2011a, b, 2012a). Among such metals is zirconium (Zr), which has the atomic number 40 and is a transition metal that resembles titanium in physical and chemical properties (Zaccone et al. 2008). Zr is widely used in many chemical industry processes and in nuclear reactors (Sandoval et al. 2011; Kamal et al. 2011), owing to its useful properties like hardness, corrosion-resistance and permeable to neutrons (Mushtaq 2012). Hence, the recent increased use of Zr by industry, and the occurrence of the Chernobyl and Fukashima catastrophe have enhanced environmental levels in soil and waters (Yirchenko and Agapkina 1993; Mosulishvili et al. 1994 ; Kruglov et al. 1996)

Use of Ponded and Fresh Ashes from China for the Production of Portland/Calcium Sulfoaluminate Clinkers

This article summarizes the use of two fly ashes in the synthesis of Portland/calcium sulfoaluminate (OPC/CSA or A/CSA) clinkers. They are from the Shentou second power plant located in the Shanxi Province and from the Zhungeer power plant located in Inner Mongolia, China. The Zhungeer ash was collected dry, and the Shentou ash is from a pond. Their chemical compositions differ highly, especially the SiO2 and Al2O3 contents. The high contents of silica and alumina make both ashes candidates as a partial or total substitute for bauxite, an expensive source of alumina, in the production of OPC/CSA clinkers. These particular hybrid clinkers are composed mainly of alite (C3S) and calcium sulfoaluminate (C4A3 ´ S), both phases responsible for the high early strength development in OPC and CSA cements, respectively. The production of high-quality OPC/CSA clinkers was produced with both ashes with the additions of hydrated lime, flue gas desulfurization (FGD) gypsum, fluorite, and bauxite at 1250°C for 60 minutes with final composition ranges of 29–41 wt% C3S, 20–22 wt% C2S, 30–45 wt% C4A3 ´ S, and 1–4 wt% C4AF

Alite calcium sulfoaluminate cement: chemistry and thermodynamics

Calcium sulfoaluminate (C$A) cement is a binder of increasing interest to the cement industry and is undergoing rapid development. Current formulations do not contain alite; however, alite calcium sulfoaluminate (a-C$A) cements can combine the favourable characteristics of Portland cement (PC) with those of C$A cement while also having a lower carbon dioxide footprint than the current generation of PC clinkers. This paper presents two results on the formation of a-C$A clinkers. The first is a thermodynamic study demonstrating that the production of a-C$A clinker is possible without the use of mineralisers, doping with foreign elements, or using multiple stages of heating. It is established that a-C$A clinker can be readily produced in a standard process by controlling the oxygen and sulfur dioxide fugacity in the atmosphere. This allows for the stabilisation of ye’elimite to the higher temperatures required for alite stability. The second result establishes that when using fluorine to mineralise a-C$A clinker production, the iron content in the clinker is also an important variable. Although the exact mechanism of alite stabilisation is not known, it is shown that alite formation increases with the combination of calcium fluoride and iron (III) oxide in the mix

Lineage Abundance Estimation for SARS-CoV-2 in Wastewater Using Transcriptome Quantification Techniques

Effectively monitoring the spread of SARS-CoV-2 mutants is essential to efforts to counter the ongoing pandemic. Predicting lineage abundance from wastewater, however, is technically challenging. We show that by sequencing SARS-CoV-2 RNA in wastewater and applying algorithms initially used for transcriptome quantification, we can estimate lineage abundance in wastewater samples. We find high variability in signal among individual samples, but the overall trends match those observed from sequencing clinical samples. Thus, while clinical sequencing remains a more sensitive technique for population surveillance, wastewater sequencing can be used to monitor trends in mutant prevalence in situations where clinical sequencing is unavailable

Standardizing data reporting in the research community to enhance the utility of open data for SARS-CoV-2 wastewater surveillance

SARS-CoV-2 RNA detection in wastewater is being rapidly developed and adopted as a public health monitoring tool worldwide. With wastewater surveillance programs being implemented across many different scales and by many different stakeholders, it is critical that data collected and shared are accompanied by an appropriate minimal amount of meta-information to enable meaningful interpretation and use of this new information source and intercomparison across datasets. While some databases are being developed for specific surveillance programs locally, regionally, nationally, and internationally, common globally-adopted data standards have not yet been established within the research community. Establishing such standards will require national and international consensus on what meta-information should accompany SARS-CoV-2 wastewater measurements. To establish a recommendation on minimum information to accompany reporting of SARS-CoV-2 occurrence in wastewater for the research community, the United States National Science Foundation (NSF) Research Coordination Network on Wastewater Surveillance for SARS-CoV-2 hosted a workshop in February 2021 with participants from academia, government agencies, private companies, wastewater utilities, public health laboratories, and research institutes. This report presents the primary two outcomes of the workshop: (i) a recommendation on the set of minimum meta-information that is needed to confidently interpret wastewater SARS-CoV-2 data, and (ii) insights from workshop discussions on how to improve standardization of data reporting

Influence of fly ash blending on hydration and physical behavior of Belite-Alite-Ye'elimite cements

A cement powder, composed of belite, alite and ye’elimite, was blended with 0, 15 and 30 wt% of fly ash and the resulting lended cements were further characterized. During hydration, the presence of fly ash caused the partial inhibition of both AFt degradation and belite reactivity, even after 180 days. The compressive strength of the corresponding mortars increased by increasing the fly ash content (68, 73 and 82 MPa for mortars with 0, 15 and 30 wt% of fly ash, respectively, at 180 curing days), mainly due to the diminishing porosity and pore size values. Although pozzolanic reaction has not been directly proved there are indirect evidences.This work is part of the Ph.D. of D. Londono-Zuluaga funded by Beca Colciencias 646—Doctorado en el exterior and Enlaza Mundos 2013 program grant. Cement and Building materials group (CEMATCO) from National University of Colombia is acknowledged for providing the calorimetric measurements. Funding from Spanish MINECO BIA2017-82391-R and I3 (IEDI-2016-0079) grants, co-funded by FEDER, are acknowledged