A comparison of self-reported motor vehicle collision injuries compared with official collision data: an analysis of age and sex trends using the Canadian National Population Health Survey and Transport Canada data

OBJECTIVE: The purpose of this study was to compare the age and sex trends of motor vehicle collision injuries between a nationally representative self-report survey and official police motor vehicle collision report data. To do this, population-based estimates of motor vehicle collision injuries were established using data from the National Population Health Survey (NPHS), a prospective, population-based, longitudinal survey that was compared to Transport Canada's official motor vehicle collision report statistics. METHODS: Aggregated mean data (1994-1996) were compared for seven age groups (15-19, 20-24, 25-34, 35-44, 45-54, 55-64, and 65+) from both data sets. RESULTS: No significant differences were found between males' and females' MVC injuries for any age category in the NPHS. A comparison of the NPHS and Transport Canada data found two small (significant) within-sex differences between the data sets, but overall, the analysis largely revealed similar trends for self-reported injury for all age categories and sex. CONCLUSIONS: The results indicate that the incidence of injuries based on self-report data in a nationally representative sample is similar to official sources of reporting and are thus a valid indicator or motor vehicle collision injury incidence. The results also confirm that injury trends differ from fatality trends.     

Continuous wave terahertz spectrometer as a noncontact thickness measuring device

We present a low cost terahertz (THz) spectrometer with coherent detection based on two simple and robust dipole antennas driven by two laser diodes. The spectrometer covers frequencies up to 1 THz, with a peak signal-to-noise ratio exceeding 40 dB for a lock-in integration time of 30 ms. We demonstrate that the thickness profile of a sample can be reconstructed from an acquired THz image.     

Electrical characteristics of high-quality sub-25-Å oxidesgrown by ultraviolet ozone exposure at low temperature

We have developed a method for controllably and reproducibly growing self-limiting ultrathin oxides with excellent electrical properties in the range ~10-25 Å thick at temperatures ranging from 25 to 600°C, respectively, using an ultraviolet ozone (UVO₃) oxidation process. The self-limiting thickness depends primarily on the substrate temperature, allowing ultrathin oxide growth with precision and reproducibility using this UVO₃ process. Oxides grown by this method are comparable in electrical quality to thermal oxides, with similar leakage current densities and breakdown fields E_BD>10 MV/cm. Current-voltage (I-V) analysis shows oxide thickness uniformity to within 1% from center to edge of a 4-in wafer. Capacitance-voltage (C-V) characterization of ~25 Å oxides shows excellent saturation behaviour, with low midgap interface trap densities and no hysteresis or dispersion     

Silicone Rubber Tack I: Relation to Network Structure

The influence of the network structure on the poly(dimethyl siloxane) (PDMS) rubber is described. The telechelic polymers have crosslinking sites restricted to the ends of polymer chains only, giving well-defined networks. Rubber-rubber tack is related to the network structure, mostly to the amount of loose polymer chains not linked into the network, that can diffuse through the interface. The amount of mobile chains can be adjusted by varying crosslinker amount and functionality. By controlled variation of the degree of crosslinking of the telechelic silicone rubbers, various levels of tack are induced, which may be related to the network topology.     

Aldonamide-type gemini surfactants: Synthesis, structural analysis, and biological properties

A new group of nonionics, so-called sugar surfactants having a gemini structure, N,N′-bisalkyl-N,N′-bis[(3-gluconylamido)propyl]ethylenediamines [bis(C _n GA): C _n =n-C₈H₁₇, n-C₁₂H₂₅], N,N′-bisdodecyl-N,N′-bis[(3-glucoheptonylamido)propyl]ethylenediamine [bis(C₁₂GH)], and N,N′-bisalkyl-N,N′-bis[(3-lactobionylamido)propyl]ethylenediamines [bis(C _n LA): C _n =n-C₈H₁₇, n-C₁₂H₂₅], were prepared in a convenient four-step procedure from easily accessible reagents. Their structure and purity were confirmed by means of elemental analysis, electrospray ionization MS (ESI-MS), and NMR spectra—¹H, ¹³C, ¹H−¹³C COSY, and distortionless enhancement by polarization transfer. All tested surfactants were practically nontoxic to gram-negative bacteria and fungi, but they inhibited the growth of some gram-positive bacteria. From the results of the Closed Bottle test (OECD Guideline 301D) for biodegradability measurements, it was concluded that the tested aldonamide gemini structures are biodegraded by environmental microorganisms to 16–55% of the initial levels by day 28, the extent depending on both the aldonamide type and the alkyl chain length. Consequently, N,N′-bisalkyl-N,N′-bis[(3-aldonylamido)propyl]ethylenediamines are a surfactant class having low ecotoxicity and fulfilling requirements desired from an ecological standpoint.     

Ignition of methane and propane in high-temperature oxidizers with various oxygen concentrations

In this investigation, ignition processes of methane (CH₄ > 98%) and propane (C₃H₈ > 95%) using a high-temperature oxidizer (T_oxi > T_ai) with a varying oxygen concentration (z_O2=0.05÷0.21), applying two types of experimental installations, viz. a constant-volume bomb (CVB) and a co-flow reactor (CFR) were investigated. The influence of the initial temperature of the oxidizer (for methane T_oxi = 960 ÷ 1234 K and for propane T_oxi = 803 ÷ 1055 K), the equivalence ratio and oxygen concentration in the oxidizer on ignition of gaseous fuels is analyzed and discussed. It is shown that in order to achieve an effective reaction of ignition (taking into account the minimum value of ignition delay time τ_ig and maximal value of the increment of temperature ΔT) the oxidizer temperature need not be maximized. There are optimal values of temperature of the oxidizer (for methane T_oxi ≈ 1100 K and for propane T_oxi ≈ 950 K) in which the parameters mentioned above reach their extreme values.     

Theoretical and experimental investigation of biomass gasification process in a fixed bed gasifier

This investigation concerns the process of air biomass gasification in a fixed bed gasifier. Theoretical equilibrium calculations and experimental investigation of the composition of syngas were carried out and compared with findings of other researchers. The influence of excess air ratio (λ) and parameters of biomass on the composition of syngas were investigated. A theoretical model is proposed, based on the equilibrium and thermodynamic balance of the gasification zone.The experimental investigation was carried out at a setup that consists of a gasifier connected by a pipe with a water boiler fired with coal (50 kWth). Syngas obtained in the gasifier is supplied into the coal firing zone of the boiler, and co-combusted with coal. The moisture content in biomass and excess air ratio of the gasification process are crucial parameters, determining the composition of syngas. Another important parameter is the kind of applied biomass. Despite similar compositions and dimensions of the two investigated feedstocks (wood pellets and oats husk pellets), compositions of syngas obtained in the case of these fuels were different. On the basis of tests it may be stated that oats husk pellets are not a suitable fuel for the purpose of gasification.     

Preparation and properties of new lactose-based surfactants

A new group of nonionic saccharide-based surfactants, N-alkanoyl-N-methyllactitolamines (alkanoyl: decanoyl, lauroyl, myristoyl, palmitoyl, stearoyl), were synthesized and characterized. Surface properties such as critical micelle concentration, standard free energy of adsorption, standard free energy of micellization, surface tension reduction efficiency, effectiveness of surface tension reduction, surface excess concentration, and surface area demand per molecule as well as foaming properties (i.e., foam volume and foam stability), contact angle, antiraicrobial activity, and biodegradability were determined. The selected performance properties were evaluated in relation to commercially available alkyl polyglucosides (Glukopon 600 EC(HH)-a Henkel product), and oligooxyethylenated decyl (C₁₀E₄) and dodecyl (E₁₂E₅) alcohols. The foaming-stabilizing effect and contact angle suggest that the lactose-derived surfactants that were studied share some common properties with alkyl polyglucosides that are different from those with an oligooxyethylene grouping. All tested N-alkanoyl-N-methyllactitolamines were practically nontoxic to bacteria and yeasts. These compounds are readily biodegradable in the Closed Bottle test inoculated with activated sludge. N-Alkanoyl-N-methyllactitolamines with lower chain lengths (C₁₀–C₁₄) biodegraded at a slightly faster rate. Biological properties showed that this class of compounds fulfills all requirements needed for environmental acceptance.     

Bildung 4.0: Herausforderungen für die Aus- und Fortbildung

The digital transformation as well as the changes leading towards a “new work” world create huge challenges regarding the education and life-long learning of process engineers. Higher education institutions and lecturers do not only have to deal with all the new opportunities and changes for themselves but need to take the specifics and expectations of the future digital natives student generation into account. Likewise, industry needs to substantially foster and increase their life-long learning offers for the workforce to safeguard employability as well as competitiveness.