The generation of residual flows in Norway: an input-output approach

The generation of 35 different kinds of residuals is analyzed by an input-output approach for the Norwegian economy in 1970. The general tendency in the computations is that the final demand category, Export, especially export from the sectors Pulp and paper and Metals and minerals, is the main contributor of the flow of residuals generated each year.     

Tympanal mechanics and neural responses in the ears of a noctuid moth

Ears evolved in many groups of moths to detect the echolocation calls of predatory bats. Although the neurophysiology of bat detection has been intensively studied in moths for decades, the relationship between sound-induced movement of the noctuid tympanic membrane and action potentials in the auditory sensory cells (A1 and A2) has received little attention. Using laser Doppler vibrometry, we measured the velocity and displacement of the tympanum in response to pure tone pulses for moths that were intact or prepared for neural recording. When recording from the auditory nerve, the displacement of the tympanum at the neural threshold remained constant across frequencies, whereas velocity varied with frequency. This suggests that the key biophysical parameter for triggering action potentials in the sensory cells of noctuid moths is tympanum displacement, not velocity. The validity of studies on the neurophysiology of moth hearing rests on the assumption that the dissection and recording procedures do not affect the biomechanics of the ear. There were no consistent differences in tympanal velocity or displacement when moths were intact or prepared for neural recordings for sound levels close to neural threshold, indicating that this and other neurophysiological studies provide good estimates of what intact moths hear at threshold.     

Prioritizing occupational injury prevention in the construction industry: injury severity or absence?

PROBLEM: National occupational injury prevention goals often prioritize the reduction of serious injuries. This study analyzed whether this prioritization is credible in respect to lost-time injuries and short and long term work absence, and the implications this has for injury severity-based versus injury absence-based prevention approaches. METHOD: The data consisted of national and work-site specific injury and absence data from construction workers in Denmark, including workers from the Copenhagen Metro construction sites, during the period 2000-2001. RESULTS AND IMPACT ON INDUSTRY AND GOVERNMENT: Absence length was significantly dependent on the type of injury. Sprains and strains were most prevalent and accounted for approximately one third of injuries and absence. Fractures accounted for one sixth of injuries and the greatest proportion of long-term absence. The results give credibility to the need for targeting sprains and strains in injury and absence prevention initiatives.     

The dichotomy of relative humidity on indoor air quality

Dry and irritated mucous membranes of the eyes and airways are common symptoms reported in office-like environments. Earlier studies suggested that indoor pollutants were responsible. We have re-evaluated, by review of the literature, how low relative humidity (RH) may influence the immediately perceived indoor air quality (IAQ), including odour, and cause irritation symptoms (i.e. longer-term perceived IAQ). "Relative humidity" were searched in major databases, and combined with: air quality, cabin air, dry eyes, formaldehyde, inflammation, mucous membranes, offices, ozone, pungency, sensory irritation, particles, precorneal tear film, sick building syndrome, stuffy air, and VOCs. The impact of RH on the immediately and longer-term perceived IAQ by VOCs, ozone, and particles is complex, because both the thermodynamic condition and the emission characteristics of building materials are influenced. Epidemiological, clinical, and human exposure studies indicate that low RH plays a role in the increase of reporting eye irritation symptoms and alteration of the precorneal tear film. These effects may be exacerbated during visual display unit work. The recommendation that IAQ should be "dry and cool" may be useful for evaluation of the immediately perceived IAQ in material emission testing, but should be considered cautiously about the development of irritation symptoms in eyes and upper airways during a workday. Studies indicate that RH about 40% is better for the eyes and upper airways than levels below 30%. The optimal RH may differ for the eyes and the airways regarding desiccation of the mucous membranes.     

Determination of technetium-99 using electrothermal vaporization inductively coupled plasma-mass spectrometry (ETV-ICP-MS) and NH4OH as chemical modifier

In recent years, developments in ICP-MS have led to improved methods for determination of long-lived radionuclides. This paper reports the use of NH(4)OH as a matrix modifier and ETV sample introduction for the determination of technetium-99 ((99)Tc) in a variety of environmental and biological samples, using Re as carrier and (99m)Tc as yield monitor in the chemical separation method. Addition of an excess of NH(4)OH led to a stable (99)Tc signal, reduced memory effect, better reproducibility and reduced detection limits. Following radiochemical separation of (99)Tc from the sample matrix, detection limits in the order of a few microBq have been achieved. ETV has also proved applicable for rapid, direct analysis of a number of environmental samples having relatively high concentrations of (99)Tc (sediment extracts and river water close to nuclear installations). However, in this case, control of matrix effects (signal reduction and enhancement) using standard additions is necessary.     

Sexual dimorphism in immune function changes during the annual cycle in house sparrows

Difference between sexes in parasitism is a common phenomenon among birds, which may be related to differences between males and females in their investment into immune functions or as a consequence of differential exposure to parasites. Because life-history strategies change sex specifically during the annual cycle, immunological responses of the host aiming to reduce the impact of parasites may be sexually dimorphic. Despite the great complexity of the immune system, studies on immunoecology generally characterise the immune status through a few variables, often overlooking potentially important seasonal and gender effects. However, because of the differences in physiological and defence mechanisms among different arms of the immune system, we expect divergent responses of immune components to environmental seasonality. In male and female house sparrows (Passer domesticus), we measured the major components of the immune system (innate, acquired, cellular and humoral) during four important life-history stages across the year: (1) mating, (2) breeding, (3) moulting and (4) during the winter capture and also following introduction to captivity in aviary. Different individuals were sampled from the same population during the four life cycle stages. We found that three out of eight immune variables showed a significant life cycle stage × sex interaction. The difference in immune response between the sexes was significant in five immune variables during the mating stage, when females had consistently stronger immune function than males, while variables varied generally non-significantly with sex during the remaining three life cycle stages. Our results show that the immune system is highly variable between life cycle stages and sexes, highlighting the potential fine tuning of the immune system to specific physiological states and environmental conditions.     

The influence of shade trees on coffee quality in small holder coffee agroforestry systems in Southern Colombia

Production of coffee, especially by small holders, is often associated with various forms of shade management. To analyse the effects of shade on physical coffee quality and on sensorial cup quality of Coffea arabica L. cv. Caturra KMC, a study was carried out with 94 plots on 16 farms in two municipalities, Timaná and Oporapa, located at elevations from 1272 to 1730 masl. in Huila, Colombia. The study was designed with emphasis on shade cover variation within each of the two study areas, while minimizing the variability of environment, agronomic management other than shade, and post-harvest processing. 46 samples of shade coffee and 46 samples of sun coffee were evaluated for physical and sensorial attributes using three professional coffee cuppers (assessors). A principal component analysis including all quality and environmental variables showed that sensory attributes were influenced negatively by shade, and that physical attributes were influenced positively by altitude. A mixed linear model, with coffee cupper and farm as random variables, revealed different shade effects on coffee quality in the two areas. In Oporapa, situated at high altitudes, shade had a negative effect on fragrance, acidity, body, sweetness and preference of the beverage, while no effect was found on the physical quality. In Timaná, situated at lower altitudes, shade did not have a significant effect on sensorial attributes, but significantly reduced the number of small beans. At high altitudes with low temperatures and no nutrient or water deficits, shade trees may thus have a partly adverse effect on C. arabica cv. Caturra resulting in reduced sensory quality. The occurrence of berry borer (Hypothenemus hampei) was lower at high altitudes and higher under shade. Future studies on shade and coffee quality should focus on the interaction between physical and chemical characteristics of beans.