Maternal depression and early positive parenting predict future conduct problems in young children with attention-deficit/hyperactivity disorder.

Children with attention-deficit/hyperactivity disorder (ADHD) are at risk for adverse outcomes such as substance abuse and criminality, particularly if they develop conduct problems. Little is known about early predictors of the developmental course of conduct problems among children with ADHD, however. Parental psychopathology and parenting were assessed in 108 children who first met Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria for ADHD at 4-7 years old. When demographic variables and baseline ADHD and conduct problems were controlled, maternal depression predicted conduct problems 2-8 years following the initial assessment, whereas positive parenting during the structured parent- child interaction task predicted fewer future conduct problems. These findings suggest that maternal depression is a risk factor, whereas early positive parenting is a protective factor, for the developmental course of conduct problems among children with ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gasification of greek lignite in an indirect heat (allothermal) rotary kiln gasifier

This work reports the performance results of a pilot-size lignite gasification plant. The feed material was Greek lignite (Megalopolis), currently being employed for electricity generation in pulverized lignite-fired thermoelectric stations. Low energy conversion efficiency, low station availability, and environmental issues call for developing improved processes, e.g., an IGCC (Integrated Gasification Combined Cycle). An indirect heat (allothermal) rotary kiln was selected as the lignite gasification reactor for developing an overall gasification process of improved efficiency. Weeklong gasification runs, at near atmospheric pressure and maximum temperature in the range 900-950°C, validated high DAF lignite conversions, i.e., 90-95%, and the production of a medium heating value synthesis gas (i.e., 11-13 MJ/Nm 3 dry basis), despite the use of air for burning recycled product gas for process heating. Gas composition is equivalent to that of autothermal gasifiers (e.g., Lurgi, Winkler, Koppers-Totzek), which operate on oxygen, under pressure and strict moisture and particle size specifications. Similarly, the kiln gas is comparable to that of an allothermal, high-pressure, fluidized bed gasifier running with a high rank coal feed. The data indicate satisfactory gasification efficiency and a good thermal efficiency that should be improved further through heat integration of a scaled-up process based on an indirect heat rotary kiln gasifier.     

Non-lactic acid, contaminating microbial flora in ready-to-eat foods: a potential food-quality index

The bacteriological profile of 87 samples of commercially available ready-to-eat (RTE) dairy and meat-products, packaged sandwiches and salads was obtained by testing for aerobic colony count, for lactic acid bacterial (LAB) count, for the presence and the extent of non-LAB microflora (contaminating microflora), and by testing for certain food-borne pathogens. The pathogens Listeria monocytogenes, Salmonella spp. and sulfite-reducing clostridia were not detected in any of the analysed samples. Whereas only three samples (3.4%) were deemed unacceptable for consumption for exceeding the established pathogen tolerance levels (for Staphylococcus aureus and Escherichia coli), several samples were found to contain non-lactic acid contaminating microflora of considerable magnitude. The log10 cfu g(-1) counts for contaminating microflora in the food categories examined were as follows: hard cheeses 4.85 (SD 1.17); semi-hard cheeses 5.39 (SD 1.37); soft cheeses 5.13 (SD 1.03); whey cheeses 6.55 (1.24); fermented meat-products 4.18 (SD 1.48); heat-treated meat-products 3.47 (SD 1.99); salads 3.37 (SD 1.56) and sandwiches 5.04 (SD 0.96). Approximately 1 in every 30 to 80 bacterial cells found on different types of cheeses and salads was a non-LAB microorganism; the respective ratios for fermented meat-products, heat-treated meat-products and sandwiches were 1 in 6, 2.5 and 15. The assessment of the contaminating microflora magnitude at various steps during the manufacture and distribution of RTE foods can serve as an index for monitoring the microbiological quality of the starting materials, the sanitation efficacy during processing and possible temperature abuse during processing, transportation or storage.     

GASIFICATION OF GREEK LIGNITE IN AN INDIRECT HEAT (ALLOTHERMAL) ROTARY KILN GASIFIER

This work reports the performance results of a pilot-size lignite gasification plant. The feed material was Greek lignite (Megalopolis), currently being employed for electricity generation in pulverized lignite-fired thermoelectric stations. Low energy conversion efficiency, low station availability, and environmental issues call for developing improved processes, e.g., an IGCC (Integrated Gasification Combined Cycle). An indirect heat (allothermal) rotary kiln was selected as the lignite gasification reactor for developing an overall gasification process of improved efficiency. Weeklong gasification runs, at near atmospheric pressure and maximum temperature in the range 900-950°C, validated high DAF lignite conversions, i.e., 90-95%, and the production of a medium heating value synthesis gas (i.e., 11-13 MJ/Nm 3 dry basis), despite the use of air for burning recycled product gas for process heating. Gas composition is equivalent to that of autothermal gasifiers (e.g., Lurgi, Winkler, Koppers-Totzek), which operate on oxygen, under pressure and strict moisture and particle size specifications. Similarly, the kiln gas is comparable to that of an allothermal, high-pressure, fluidized bed gasifier running with a high rank coal feed. The data indicate satisfactory gasification efficiency and a good thermal efficiency that should be improved further through heat integration of a scaled-up process based on an indirect heat rotary kiln gasifier.     

Cesium Release From Tungstate and Titanate Waste Form Materials in Simulated Canister Corrosion Product-Containing Solutions

The leaching of two potential ¹³⁷Cs waste form ceramics (Cs-containing hexagonal tungsten bronze (HTB) and hollandite) has been investigated in Fe(NO₃)₃ solutions of increasing concentration at 150°C over a period of 4 days. These ceramics contain within their structures reduced Mo⁵⁺/W⁵⁺ and Ti³⁺ species for the HTB and hollandite, respectively, which therefore might render them susceptible to oxidation-induced leaching. Elucidation of the extent and the mechanism of leaching of the Cs from these ceramics in the REDOX active iron nitrate medium has been investigated. Cesium (Cs) leached severely from both the Cs-loaded HTB and hollandite materials in iron nitrate solutions with virtually all of the immobilized Cs being extracted from both waste form materials in a period of 4 days at 150°C. In the case of hollandite, conversion to ilmenite and hematite was observed at low concentrations and was virtually complete in 0.5 mol/L Fe(NO₃)₃ over 4 days. In the case of the HTB, all of the Cs was extracted presumably by an ion-exchange mechanism because the structure of this oxide remained intact and iron was found in the composition. Iron oxide with a hematite structure was also easily observed in the reacted sample at high solution iron concentrations. It is shown that the leach resistance of the Cs-containing HTB can be improved by substitution of up to 20% Ti for W.     

Extreme Spectra of Var Models and Orders of Near‐Cointegration

Abstract. In this paper, we study the spectral properties of a bivariate vector autoregressive VAR(p) model when a root z₀ = ρ₀e^iλ0 of the determinant of the model's characteristic matrix Φ(z) approaches the unit circle, the border of non‐stationarity. Let Φ_xx(z), Φ_xy(z), Φ_yx(z), Φ_yy(z) be the polynomial elements of Φ(z). We show that, depending on the relation of the order of z₀ as root of det(Φ(z)) with the orders of z₀ as root of Φ_ij(z), (i,j ∈ {x,y}), the two marginal spectra may tend to infinity at λ₀, while the coherence may tend to unity at λ₀. We investigate the conditions under which any of the above will occur, in detail. In the specific case where z₀→1, the marginal series will be near‐integrated of certain orders of near‐integration, while there will eventually exist a linear combination of them with a lower order of near‐integration. We study the possible combinations of their orders of near‐integration. Finally, we develop a strategy with the help of which one may define a VAR(p) model with pre‐specified extreme spectral features and give some examples. Beyond the benefits of this latter for VAR model simulation, the analysis has, moreover, implications concerning the adequacy of VAR model fitting.     

Evaluation of a long-range lightning detection network with receivers in Europe and Africa

This study focuses on the performance evaluation of the experimental long-range lightning detection network Zeus, with receivers located in Europe and Africa. The evaluation is carried out in terms of locating error and detection performance. Zeus' receivers record the radio noise (sferics) emitted by cloud-to-ground lightning discharges in the very low frequency (bandwidth between 5 and 15 kHz). The lightning location is retrieved by means of the arrival time difference (ATD) triangulation technique. The presented study includes evaluation of the system's locating error and detection performance over the African continent, equatorial/mid-Atlantic, the Caribbean, and northern South America. This dataset is validated over a period extending from July through October 2004. The Lightning Imaging Sensor onboard NASA's Tropical Rainfall Measuring Mission satellite is used as the validation source. The analysis shows that the number of receivers as well as their relative location (relative position of the flash-event to the network's receivers) plays a key role in the retrieval error magnitude. Median error values within the network's periphery are found to be approximately 20 km, while outside the periphery significantly larger (/spl sim/130 km). Simulation of chi-square values, implemented from the ATD algorithm, shows an adequate agreement between theoretical error-related computations and the network's retrievals. In terms of detection performance, the Zeus system is also validated over the same area/period. The chief observation is that the detection performance is likewise dependent on the number of receivers used by the system rather than their relative location.     

Probing the physiology of ASH neuron in Caenorhabditis elegans using electric current stimulation

Electrical stimulation has been widely used to modulate and study the in vitro and in vivo functionality of the nervous system. Here, we characterized the effect of electrical stimulation on ASH neuron in Caenorhabditis elegans and employed it to probe the neuron's age dependent properties. We utilized an automated microfluidic-based platform and characterized the ASH neuronal activity in response to an electric current applied to the worm's body. The electrically induced ASH neuronal response was observed to be dependent on the magnitude, polarity, and spatial location of the electrical stimulus as well as on the age of the worm.