Primary tooth abscess caused by Mycobacterium bovis in an immunocompetent child

Bovine tuberculosis is a zoonotic disease, and although its incidence has dramatically decreased in developed countries where effective control measures are applied, it still remains a potential health hazard in the developing world. Tuberculosis of the oral cavity is extremely rare and is usually secondary to pulmonary involvement. We present the unusual case of an immunocompetent 6-year-old child residing in an urban area with primary oral tuberculosis due to Mycobacterium bovis, which was confirmed by the application of a molecular genetic approach. M. bovis belongs to Mycobacterium tuberculosis complex which comprises species with close genetic relationship, and for this reason, the use of new molecular techniques is a useful tool for the differentiation at species level of the closely related members of this complex

DATAMAN: A global database of methane, nitrous oxide, and ammonia emission factors for livestock housing and outdoor storage of manure

Livestock manure management systems can be significant sources of nitrous oxide (N2O), methane (CH4), and ammonia (NH3) emissions. Many studies have been conducted to improve our understanding of the emission processes and to identify influential variables in order to develop mitigation techniques adapted to each manure management step (animal housing, outdoor storage, and manure spreading to land). The international project DATAMAN (http://www.dataman.co.nz) aims to develop a global database on greenhouse gases (N2O, CH4) and NH3 emissions from the manure management chain to refine emission factors (EFs) for national greenhouse gas and NH3 inventories. This paper describes the housing and outdoor storage components of this database. Relevant information for different animal categories, manure types, livestock buildings, outdoor storage, and climatic conditions was collated from published peer reviewed research, conference papers, and existing databases published between 1995 and 2021. In the housing database, 2024 EFs were collated (63% for NH3, 19.5% for CH4, and 17.5% for N2O). The storage database contains 654 NH3 EFs from 16 countries, 243 CH4 EFs from 13 countries, and 421 N2O EFs from 17 countries. Across all gases, dairy cattle and swine production in temperate climate zones are the most represented animal and climate categories. As for the housing database, the number of EFs for the tropical climate zone is under-represented. The DATAMAN database can be used for the refinement of national inventories and better assessment of the cost-effectiveness of a range of mitigation strategies

Use of Cadastral Data for the Development of Spatial Decision Support Systemsfor Coping with the Consequences of Natural Disasters

This paper investigates the potential usefulness of cadastral data to form the core part of databases of Spatial Decision Support Systems [SDSS] that are capable to support decision-makers in dealing with emergency situations, such as earthquakes, floods and fires. Particular emphasis is given on how those data can be used to generate information that is necessary to planners and decision-makers when they cope with natural disasters at every stage of the development of the disaster: before the occurrence (planning and preventive measures), immediately after occurrence (short term measures), and well-after occurrence (medium and long term measures). This investigation is conducted using the Municipality of Magoula, Attica, Greece, as a case study area. This municipality is situated in the greater Athens area and was struck by the earthquake that occurred there in September 1999. Within the scope of the project, wehave used cadastral data about the study area and data recorded by the inspection teams in order to set-up a prototype SDSS database that could facilitate planning and decision-making in such a situation. Then, we have used that prototype to generate scenarios and information about typical tasks that are performed during emergency situations. The advantages that are realized from the integration of such data and information technologies are described and assessed, particularly, in comparison with the traditional approaches that are used in such situations

Partitioning thermal habitat on a vertical rock, a herculean task

Species occurring in sympatry have to effectively segregate their niche in order to co-exist. In the case of ectotherms in particular, the very important parameter of thermal biology has to be taken into account. Here we investigated the thermoregulatory effectiveness (E) of two endemic Greek lizards (Hellenolacerta graeca and Podarcis peloponnesiacus) that live syntopically on a rocky cliff in the Peloponnese. We presumed that the two species would select different microhabitats, to avoid interspecific competition, and follow a similar thermoregulation pattern as they experience the same conditions. We also expected that E values for both species would differ depending on the season. Overall, we found that the two species had similar E values for each season but differentiated partial thermoregulatory attributes. Though they both occurred in the same types of microhabitat, H. graeca selected higher sites (average 99 cm above ground) than P. peloponnesiacus (average 44 cm). Also, the latter achieved higher preferred temperatures during summer and winter. Finally, the effectiveness of thermoregulation for both species varied interseasonally and received its highest values during summer, in response to the lowest thermal quality that was observed then. Similar studies stress the importance of thermal shifts for ectotherm co-existence. © 2017 Elsevier Lt

Influence of Cu on the properties of gadolinium-doped barium cerate

In the present work the effect of copper oxide addition on the densification behavior and electrical conductivity of BaCe1-xGdxO3-delta (BCG) type ceramics is investigated. Small addition (1 mol%) of this sintering additive reduces both the calcination temperature (by similar to 250 degrees C and the sintering temperature (by -150 degrees C) and promotes at the same time the densification process. According to the X-ray diffraction analysis the BaCe1-xGdxO3-delta samples with 0 <= x <= 0.2 and the BaCe1-xGdxO3-delta samples with 0.0075 <= y <= 0.07 are single-phase. It was found that the samples with Cu, when sintered at 1450 degrees C for 3 h, have similar to 95% of relative density compared with pure BaCe1-xGd0.1CuyO3-delta samples that have similar to 86%. It was also found that the electrical conductivity of Cu-containing samples sintered at 1450 degrees C is comparable to those without Cu sintered at 1600 degrees C in oxidizing and reducing atmospheres. Cu-containing samples exhibit significantly higher conductivity in both air and hydrogen atmosphere. (c) 2007 Elsevier B.V. All rights reserved

The effect of cobalt oxide addition on the properties of gadolinium doped barium cerate

In the present work the effect of cobalt oxide addition on the density and on the electrical properties of gadolinium doped barium cerate is investigated. A series of BaCe0.9-xGd0.1CoxO3-δ (?=0.00, 0.01, 0.03, 0.05, 0.07, 0.10) samples were prepared according to the conventional solid state reaction synthesis technique. The experimental results indicated that the addition of cobalt oxide leads to the improvement of the sintering properties and the enhancement of the grain dimensions. According to the four-probe dc electrical conductivity measurements, in the temperature interval of 600-900°C the values of electrical conductivity of the BaCe0.9-?Gd0.1Co?O3-δ samples are lower than those of the undoped BaCe0.9Gd0.1O3-δ in wet air. However, in reducing atmosphere this difference becomes very small in the case of BaCe0.89Gd0.1Co0.01O3- δ, leading to the conclusion that cobalt can be successfully employed as a sintering additive of gadolinium doped barium cerates

High surface area tungsten carbide microspheres as effective Pt catalyst support for oxygen reduction reaction

In the present work, the preparation of high surface area (256 m2 g-1) tungsten carbide microspheres (TCMSs) by the aid of a simple hydrothermal method is realized and the performance of the Pt electrocatalyst supported on the as-prepared TCMSs towards the oxygen reduction reaction (ORR) is investigated. The SEM micrographs indicated that both the synthesized carbon microspheres (CMSs) and TCMSs showed perfect microsphere structure and uniform size. The EDX measurements confirmed that when the C/W mass ratio is ∼2.5/1, tungsten and carbon coexist in the microspheres. Moreover, from the XRD results, it can be found that both W2C and WC are detected and W2C exists as the main phase. It was found that the Pt particles are uniformly dispersed on the supports, while the corresponding average particle size is ∼3.7, 4.1 and 4.3 nm for Pt/C, Pt/CMSs and Pt/TCMSs, respectively. It was also found that in terms of ORR onset potential and mass activity, the Pt/TCMSs catalyst exhibits superior performance to that of Pt/CMSs and Pt/C, enhancing the ORR catalytic activity by more than 200%. The above behavior could be attributed to its higher electrochemical surface area (ESA), as well as to the synergistic effect between Pt and tungsten carbides. © 2008 Elsevier B.V. All rights reserved

KOH-activated multi-walled carbon nanotubes as platinum supports for oxygen reduction reaction

In the present investigation, multi-walled carbon nanotubes (MWCNTs) thermally treated by KOH were adopted as the platinum supporting material for the oxygen reduction reaction electrocatalysts. FTIR and Raman spectra were used to investigate the surface state of MWCNTs treated by KOH at different temperatures (700, 800, and 900 °C) and showed MWCNTs can be successfully functionalized. The structural properties of KOH-activated MWCNTs supported Pt were determined by X-ray diffraction (XRD) and transmission electron microscopy (TEM), and their electrochemical performance was evaluated by the aid of cyclic voltammetry (CV) and rotating disk electrode (RDE) voltammetry. According to the experimental findings of the present work, the surrface of MWCNTs can be successfully functionalized with oxygen-containing groups after activation by KOH, favoring the good dispersion of Pt nanoparticles with narrow size distribution. The as-prepared Pt catalysts supported on KOH treated MWCNTs at higher temperature, possess higher electrochemical surface area and exhibit desirable activity towards oxygen reduction reaction (ORR). More precisely, it has been found that the electrochemical active area of Pt/MWCNTs-900 is approximately two times higher than that of Pt/MWCNTs. It can be concluded that KOH activation is an effective way to decorate MWCNTs' surface with oxygen-containing groups and bigger surface area, which makes them more suitable as electrocatalyst support materials. © 2010 Elsevier B.V

Direct ethanol solid oxide fuel cells: The case of PT anodes

The limitation of fossil fuels deposits and the detrimental effects of their combustion emissions on the environment make it necessary to develop alternative technologies, such as fuel cells and use the renewable and environmentally-friendly liquid fuels such as ethanol. The latter has been recognized as a suitable "clean" fuel for electricity generation in fuel cells and particularly in solid oxide fuel cells (SOFCs) with numerous advantages [1, 2]. Solid oxide fuel cells constitute a high temperature energy conversion technology, with the highest efficiency among all the types of fuel cells, which is unattainable from all conventional thermal engines. Moreover, their multi-fuel capability allows the utilization of various kinds of hydrocarbon related species via internal and/or via simple external reforming [3]. In the present work, an YSZ electrochemical reactor directly fed by a mixture of ethanol/water operated as a solid oxide fuel cell has been investigated. The SOFC performance has been tested over Pt anode slectrocatalyst at temperatures ranging from 550oC to 700oC. The inlet partial pressure of ethanol was kept at 5.4 kPa, while for the water 7.0 kPa. The total flow rate of the feed stream was kept constant at 23.5 ml/min. According to the experimental results, it was found that the open circuit voltage of the cell was approximately 1.0 V, while under closed circuit conditions and relatively lower temperature (550-600oC) the cell voltage dropped initially rapidly with a consequent increment of the current density, due to higher activation over-potential on Pt. which is most probably resulted from the big particle size of Pt. It can also be found that there was an obvious decrease of cell voltage along with the current density in the ohmic polarization range. This could be attributed to the low operation temperature. Under the investigated conditions, the maximum power density was 1 8 mW/cm2 at 70 mA/cm2 and at 700oC