Viewpoint: Scientific dogmas, paradoxes and mysteries of latent Mycobacterium tuberculosis infection

Worldwide, there are nearly 10 million new cases of active TB and 1.8 million associated deaths every year. WHO estimates that one-third of the world’s population is infected with Mycobacterium tuberculosis (Mtb), forming a huge latent Mtb global reservoir. This renders the prospect of ever eliminating Mtb from the human race almost impossible. Several controversial issues regarding host-pathogen interactions and existing prevention and eradication strategies for latent Mtb infections need to be critically re-examined. In this viewpoint, widely held assumptions on Mtb latency and isoniazid monotherapy and chemoprophylaxis are challenged. We highlight the need for future research to resolve these issues and to develop evidence-based strategies for better understanding of equilibrium and escape of Mtb in the human body, eventually leading to global recommendations for elimination of the latent Mtb state through informed policy and practice. Until such strategies and policies are realized, WHO and TB experts will have to settle for global TB control rather than eradication

Carbon dioxide sequestration on mortars containing recycled aggregates: A hot area for startup development

The world is closer to exceeding the budget (cumulative amount of anthropogenic CO2 emission compatible with a global temperature-change target) for the long-term target of the Paris Climate Agreement than previously thought. Three lines of evidence suggest that global warming will be faster than projected in the recent IPCC special report.  First, greenhouse-gas emissions are still rising. Second, governments are cleaning up air pollution faster than the IPCC and most models previously assumed. But aerosols, including sulfates, nitrates and organic compounds, reflect sunlight so the aforementioned cleaning could have a warming effect by as much as 0.7 ºC. And in third place, there are signs that the planet might be entering a natural warm phase because the Pacific Ocean seems to be warming up. And these three forces reinforce each other. Carbon dioxide sequestration is therefore crucial for targets for limiting global warming. Europe is now putting great efforts and funding in carbon sequestration materials and technologies. The flagship programme EnCO2re, currently looks to develop new technologies offering novel ways to use CO2; increase awareness for CO2 re-use; and ensures sustainability and social acceptance of materials and products by integrated socio-ecological research. Also Carbon capture and sequestration is one of the 100 Radical Innovation Breakthroughs for the future (Europe, 2019)..This chapter discloses results of an investigation concerning the performance of fly ash/waste glass alkaline-based mortars with recycled aggregates reinforced by hemp fibres. The results show that hemp fibres lead to a reduction of mechanical properties of alkali-activated materials.Foundation for Science and Technology (FCT) in the frame of project IF/00706/2014-UM.2.1

Carbon dioxide sequestration of fly ash alkaline based mortars with recycled aggregates and different sodium hydroxide concentrations: Properties, durability, carbon footprint, and cost analysis

This chapter discloses results of an investigation concerning carbon dioxide sequestration on fly ash/waste glass alkaline-based mortars with recycled aggregates and different sodium hydroxide concentrations. Properties, durability, carbon footprint, and cost analysis were studied on it. Mixtures using a sodium hydroxide concentration of 8M and the additive calcium hydroxide show the best performance and the lowest carbon footprint. Simulations using a carbon tax of 0.0347 Euro/kg show no influence on the cost of the mixtures while the use of the carbon tax of 0.206 Euro/kg show an increase in the cost-efficiency of mixtures, even those using a sodium hydroxide concentration of 8M and additive calcium hydroxide.The authors would like to acknowledge the financial support of the Foundation for Science and Technology (FCT) in the frame of project IF/00706/2014-UM.2.15.info:eu-repo/semantics/publishedVersio

Active surveillance of Q fever in human and animal population of Cyprus

BACKGROUND: A long-term active surveillance of Q fever was conducted in Cyprus organized in two phases. METHODS: Following serological tests and identification of seropositive humans and animals for C. burnetii in two villages (VIL1 and VIL2), all seronegative individuals were followed up for one year on a monthly basis by trained physicians to detect possible seroconversion for Q fever. In the second phase of the study, active surveillance for one year was conducted in the entire Cyprus. Physicians were following specific case definition criteria for Q fever. Standardized questionnaires, a geographical information system on a regional level, Immunofluorescence Assay (IFA) examinations and shell vial technique were used. RESULTS: Eighty-one seronegative humans and 239 seronegative animals from both villages participated in the first phase surveillance period of Q fever. Despite the small number of confirmed clinical cases (2 humans and 1 goat), a significant percentage of new seropositives for C. burnetii (44.4% of human participants and 13.8% of animals) was detected at the end of the year. During the second phase of surveillance, 82 humans, 100 goats, and 76 sheep were considered suspected cases of Q fever. However, only 9 human, 8 goat, and 4 sheep cases were serologically confirmed, while C. burnetii was isolated from three human and two animal samples. The human incidence rate was estimated at 1.2 per 100,000 population per year. CONCLUSION: A small number of confirmed clinical cases of Q fever were observed despite the high seroprevalence for C. burnetii in human and animal population of Cyprus. Most of the cases in the local population of Cyprus appear to be subclinical. Moreover further studies should investigate the role of ticks in the epidemiology of Q fever and their relation to human seropositivity

Carbon dioxide sequestration on fly ash/waste glass alkali-based mortars with recycled aggregates: Compressive strength, hydration products, carbon footprint, and cost analysis

Carbon dioxide sequestration is crucial for limiting global warming. However, carbon dioxide sequestration in saline aquifers has large risks and also involves a very high cost. In this context sequestration of carbon dioxide in cementitious construction materials can not only prevent carbon dioxide to be released into the atmosphere but also accelerate curing and strength development of those materials. Since so far no studies were performed on alkali-based materials, this chapter discloses results of an investigation concerning carbon dioxide sequestration on fly ash/waste glass alkali-based mortars with recycled aggregates. Compressive strength, hydration products, carbon footprint, and cost analysis were also studied.The authors would like to acknowledge the financial support of the Foundation for Science and Technology (FCT) in the frame of project IF/00706/2014-UM.2.15.info:eu-repo/semantics/publishedVersio