Narrative text analysis of Kentucky tractor fatality reports

Narrative information in fatality investigation reports contains data elements not routinely analyzed with coded occupational injury surveillance data. A narrative text analysis of 69 Kentucky Fatality Assessment and Control Evaluation (FACE) agricultural tractor fatality reports from 1994 to 2004 was performed. The FACE reports were developed using the National Institute for Occupational Safety and Health, Division of Safety Research-recommended FACE report format that incorporates Haddon's matrix. Haddon's matrix separates the fatal incident into three event phases and is used to develop points of intervention based on human, organizational, and environmental factors. A multivariate logistic regression analysis for association between identified exposure variables and the outcomes of interest was undertaken. The operation of a tractor with an attached bucket, muddy terrain, and being thrown from the tractor were independent risk factors for being declared "dead at the scene". A tractor rollover and operation of a tractor on a slope were independent risk factors for being "crushed" by a tractor. Narrative text analysis of FACE fatality investigation reports is a valuable tool for the identification of additional factors contributing to tractor fatalities that can inform farm safety training, identify new areas for agricultural interventions, and support the development of new agricultural engineering strategies.     

Azamacrocycle activated quantum dot for zinc ion detection

A new fluorescent nanosensor family for Zn (2+) determination is reported based on azamacrocycle derivatization of CdSe/ZnS core/shell quantum dot nanoparticles. They are the first zinc ion sensors using QD nanoparticles in a host-guest and receptor-fluorophore system. Three azamacrocycles are demonstrated as receptors: TACN (1,4,7-triazacyclononane), cyclen (1,4,7,10-tetraazacyclododecane), and cyclam (1,4,8,11-tetraazacyclotetradecane). Azamacrocycles conjugated to QDs via an amide link interact directly with one of the photoinduced QD charge carriers, probably transferring the hole in the QD to the azamacrocycle, thereby disrupting the radiative recombination process. When zinc ion enters the aza-crown, the lone pair electrons of the nitrogen atom become involved in the coordination and the energy level is no longer available for the hole-transfer mechanism, switching on the QD emission and a dramatic increase of the fluorescence intensity results, allowing the detection of low concentrations of zinc ions. Using this operating principle, three zinc ion sensors based on CdSe-ZnS core-shell QD nanoparticles showed a very good linearity in the range 5-500 microM, with detection limits lower than 2.4 microM and RSDs approximately 3% ( n = 10). In addition, the versatility of the sensors was demonstrated, since different sizes (and colors) of QDs can be employed and will respond to zinc in a similar way. In a study of interferences, the zinc-sensitive QDs showed good selectivity in comparison with other physiologically important cations and other transition metals tested. The results from fetal calf serum and samples mimicking physiological conditions suggested very good applicability in the determination of zinc ion in physiological samples.     

Characterization of the Ag mediated surface-enhanced Raman spectroscopy of saxitoxin

The rapid detection and quantification of saxitoxin (STX) is reported using surface-enhanced Raman spectroscopy (SERS) with a colloidal hydrosol of silver nanoparticles. Under the conditions of our experiments, the limit of detection (LD) for STX using SERS is 3 nM, with a limit of quantification (LQ) of 20 nM. It is shown that the SERS method is rapid, with spectra being collected in as little as 5 seconds total integration time for a 40 nM STX sample. In order to improve the signal-to-noise ratio, SERS spectra were generally collected with a total integration time of 1 minute (6 accumulations of 10 seconds each), with no need for extensive sample work-up or substrate preparation. Based on these results, the SERS technique shows great promise for the future detection and quantification of STX molecules in aqueous solutions.     

Micro-attenuated total reflection spectral imaging in archaeology: application to Maya paint and plaster wall decorations

Fourier transform infrared (FT-IR) attenuated total reflection (ATR) imaging has been successfully used to identify individual mineral components of ancient Maya paint. The high spatial resolution of a micro FT-IR-ATR system in combination with a focal plane array detector has allowed individual particles in the paint to be resolved and identified from their spectra. This system has been used in combination with micro-Raman spectroscopy to characterize the paint, which was found to be a mixture of hematite and silicate particles with minor amounts of calcite, carbon, and magnetite particles in a sub-micrometer hematite and calcite matrix. The underlying stucco was also investigated and found to be a combination of calcite with fine carbon particles, making a dark sub-ground for the paint.     

Effects of lanthanum modification on dielectric properties of Pb(Zr<Subscript>0.90</Subscript>,Ti<Subscript>0.10</Subscript>)O<Subscript>3</Subscript> ceramics: enhanced antiferroelectric stability

Lanthanum modified lead zirconate titanate ceramics with lanthanum content changing from 2 to 6 at% La and a Zr/Ti ratio of 90/10 (PLZT x/90/10) have been analyzed by using X-ray diffraction, dielectric response, differential scanning calorimetry, and ferroelectric hysteresis. An antiferroelectric state was found to be stabilized, whereas the long-range ferroelectric state was disrupted by lanthanum substitution on the lead sites. A ferroelectric state is shown to be stable over an antiferroelectric state for low lanthanum contents in a wide temperature range, where both phases coexist. With the increase of the lanthanum concentration, the long-range coherency of the ferroelectric state is suppressed, i.e., the temperature range of the ferroelectric state stability decreased, disappearing for x > 3 at% La.     

The impact of synthetic biology in chemical engineering—Educational issues

This paper describes the development of synthetic biology as a distinct entity from current industrial biotechnology and the implications for a future based on its concepts. The role of the engineering design cycle, in synthetic biology is established and the difficulties in making and exact analogy between the two emphasised. It is suggested that process engineers can offer experience in the application of synthetic biology to the manufacture of products which should influence the approach of the synthetic biologist. The style of teaching for synthetic biology appears to offer a new approach at undergraduate level and the challenges to the education of process engineers in this technology are raised. Possible routes to the development of synthetic biology teaching are suggested.     

Increased Activity of Cell Surface Peptidases in HeLa Cells Undergoing UV-Induced Apoptosis Is Not Mediated by Caspase 3

We have previously shown that in HeLa cells treated with a variety of agents there is an increase in cell surface peptidase (CSP) activity in those cells undergoing apoptosis. The increase in CSP activity observed in UVB-irradiated cells undergoing apoptosis was unaffected when the cultures were treated with the aminopeptidase inhibitor bestatin, and matrix metalloprotease inhibitor BB3103, but greatly enhanced when treated with the caspase 3 inhibitor-DEVD, and reduced in the presence of the poly(ADP-ribose) polymerase (PARP) inhibitor-3-aminobenzamide (3AB). Neither 3AB nor DEVD had an effect on the gross morphology of the apoptotic cells observed under electron microscopy, nor did they have an effect on phosphatidylserine eversion on the cell membrane, or that of PARP cleavage. All the agents except for DEVD had no effect on the level of caspase 3 activity in the cells. The results suggest that other caspases may cleave PARP in these cells. Both 3AB and DEVD treatment reduced the level of actin cleavage seen in the apoptotic cells. The increase in CSP activity observed in cells undergoing UVB-induced apoptosis appears to involve PARP but not caspase 3.     

提高低热值燃料发电效率的设计创新

发电项目中使用的工业废气被认为是低热值的燃料,难以高效地转化为电能。GE废热发电技术,使用新型高效的燃机发电方式取代锅炉发电,在武汉钢铁公司,并将在鞍山钢铁公司和邯郸钢铁公司得以应用,将高炉煤气转化为清洁能源。这一技术克服了传统难题,将废气进行压缩,使其能够驱动重型燃气轮机。