Durable Goods and the Business Cycle

Spending on durable goods tends to be more cyclical than spending on non-durable goods and services as it can be more readily postponed in times of economic weakness. During the recent global economic slowdown, the decline in durable goods spending was a key transmission mechanism of the uncertainty associated with the global financial crisis to the broader economy, as households and businesses delayed purchases of durable goods.Australia; durable goods; machinery & equipment investment; business cycle

Why huddle? Ecological drivers of chick aggregations in gentoo penguins, Pygoscelis papua, across latitudes

Aggregations of young animals are common in a range of endothermic and ectothermic species, yet the adaptive behavior may depend on social circumstance and local conditions. In penguins, many species form aggregations (aka. crèches) for a variety of purposes, whilst others have never been observed exhibiting this behavior. Those that do form aggregations do so for three known benefits: 1) reduced thermoregulatory requirements, 2) avoidance of unrelated-adult aggression, and 3) lower predation risk. In gentoo penguins, Pygoscelis papua, chick aggregations are known to form during the post-guard period, yet the cause of these aggregations is poorly understood. Here, for the first time, we study aggregation behavior in gentoo penguins, examining four study sites along a latitudinal gradient using time-lapse cameras to examine the adaptive benefit of aggregations to chicks. Our results support the idea that aggregations of gentoo chicks decrease an individual’s energetic expenditure when wet, cold conditions are present. However, we found significant differences in aggregation behavior between the lowest latitude site, Maiviken, South Georgia, and two of the higher latitude sites on the Antarctic Peninsula, suggesting this behavior may be colony specific. We provide strong evidence that more chicks aggregate and a larger number of aggregations occur on South Georgia, while the opposite occurs at Petermann Island in Antarctica. Future studies should evaluate multiple seabird colonies within one species before generalizing behaviors based on one location, and past studies may need to be re-evaluated to determine whether chick aggregation and other behaviors are in fact exhibited species-wide

Metal Cooling in Simulations of Cosmic Structure Formation

The addition of metals to any gas can significantly alter its evolution by increasing the rate of radiative cooling. In star-forming environments, enhanced cooling can potentially lead to fragmentation and the formation of low-mass stars, where metal-free gas-clouds have been shown not to fragment. Adding metal cooling to numerical simulations has traditionally required a choice between speed and accuracy. We introduce a method that uses the sophisticated chemical network of the photoionization software, Cloudy, to include radiative cooling from a complete set of metals up to atomic number 30 (Zn) that can be used with large-scale three-dimensional hydrodynamic simulations. Our method is valid over an extremely large temperature range (10 K < T < 10^8 K), up to hydrogen number densities of 10^12 cm^-3. At this density, a sphere of 1 Msun has a radius of roughly 40 AU. We implement our method in the adaptive mesh refinement (AMR) hydrodynamic/N-body code, Enzo. Using cooling rates generated with this method, we study the physical conditions that led to the transition from Population III to Population II star formation. While C, O, Fe, and Si have been previously shown to make the strongest contribution to the cooling in low-metallicity gas, we find that up to 40% of the metal cooling comes from fine-structure emission by S, when solar abundance patterns are present. At metallicities, Z > 10^-4 Zsun, regions of density and temperature exist where gas is both thermally unstable and has a cooling time less than its dynamical time. We identify these doubly unstable regions as the most inducive to fragmentation. At high redshifts, the CMB inhibits efficient cooling at low temperatures and, thus, reduces the size of the doubly unstable regions, making fragmentation more difficult.Comment: 19 pages, 12 figures, significant revision, including new figure

Criminal charges, risk assessment and violent recidivism in cases of domestic abuse

Domestic abuse is a pervasive global problem. Here we analyze two approaches to reducing violent DA recidivism. One involves charging the perpetrator with a crime; the other provides protective services to the victim on the basis of a formal risk assessment carried out by the police. We use detailed administrative data to estimate the average effect of treatment on the treated using inverse propensity-score weighting (IPW). We then make use of causal forests to study heterogeneity in the estimated treatment effects. We find that pressing charges substantially reduces the likelihood of violent recidivism. The analysis also reveals substantial heterogeneity in the effect of pressing charges. In contrast, the risk-assessment process has no discernible effect

Failure to eradicate Isospora belli diarrhoea despite immune reconstitution in adults with HIV--a case series

Isospora belli causes diarrhoea in patients with AIDS. Most respond to targeted therapy and recommendations are that secondary prophylaxis can be stopped following immune reconstitution with ART. We report eight cases of chronic isosporiasis that persisted despite standard antimicrobial therapy, secondary prophylaxis, and good immunological and virological response to ART. Median CD4 nadir was 175.5 cells/mm 3 and median highest CD4 while symptomatic was 373 cells/mm 3 . Overall 34% of stool samples and 63% of duodenal biopsy specimens were positive for oocytes. Four patients died, two remain symptomatic and two recovered. Possible explanations for persistence of symptoms include host factors such as antigen specific immune deficiency or generalised reduction in gut immunity. Parasite factors may include accumulating resistance to co-trimoxazole. Research is required to determine the optimum dose and duration of co-trimoxazole therapy and whether dual therapy may be necessary. Mortality was high and pending more data we recommend extended treatment with high-dose co-trimoxazole in similar cases

Social influences on flood preparedness and mitigation measures adopted by people living with flood risk

This paper aims to analyse evidence, based on one of the largest and most representative samples of households previously flooded or living with flood risk to date, of social patterns in a range of flood resilience traits relating to preparedness prior to a flood (e.g., property adaptations, contents insurance, etc.) and mitigations enacted during and immediately following a flood (e.g., receiving a warning, evacuation into temporary accommodation, etc.). The data were collected from a 2006 survey of 1223 households from a variety of locations across Scotland between one and twelve years after major local floods. Our analysis identifies remarkably few social differences in flood preparedness and mitigation measures, although some aspects of demography, housing and length of residence in an area, as well as personal flood history, are important. In light of this finding, we argue that social differences in vulnerability and resilience to flooding arise from deep-seated socio-economic and socio-spatial inequalities that affect exposure to flood risk and ability to recover from flood impacts. The engrained, but well-meaning, assumption in flood risk management that impoverished households and communities are lacking or deficient in flood preparedness or mitigation knowledge and capabilities is somewhat pejorative and misses fundamental, yet sometimes invisible, social stratifications play out in subtle but powerful ways to affect households’ and communities’ ability to avoid and recover from floods. We argue that general poverty and inequality alleviation measures, such as tax and welfare policy and urban and community regeneration schemes, are likely to be as, if not more, important in alleviating social inequalities in the long-term impacts of floods than social targeting of flood risk management policy

Exploring the Social Impacts of Flood Risk and Flooding in Scotland

No abstract available

Using the personal taxation regime to encourage modal shift : an international review

Correctly pricing transport behavior to take account of the ‘external’ costs such as congestion, emissions and congestion imposed on society by excessive car use has long been a tenet of effective Transportation Demand Management. But while policy makers have striven to increase public transport subsidies, raise petrol taxes, and introduce road user charging schemes to change the price of car travel, the wider influences of the personal tax regime has had relatively little attention. This paper is a review of reforms to the personal tax regime to favor more environmentally benign forms of travel and, in particular, to encourage employers to take part in TDM-type programs. The results reported are based on work undertaken for the UK Department of Transport, Local Government and the Regions, and the Inland Revenue. In addition to reporting the British situation, it also outlines how this same process has been approached in the United States, Ireland, Germany, Netherlands, Switzerland and Norway, and at how successful they have been thus far with respect to TDM objectives. It then draws conclusions as to which direction policy makers could aim for the future

A Measurement of the Temperature-Density Relation in the Intergalactic Medium Using a New Lyman-alpha Absorption Line Fitting Method

The evolution of the temperature in the intergalactic medium is related to the reionization of hydrogen and helium, and has important consequences for our understanding of the Lya forest and of galaxy formation in gravitational models of large-scale structure. We measure the temperature-density relation of intergalactic gas from Lya forest observations of eight quasar spectra with high resolution and signal-to-noise ratio, using a new line fitting technique to obtain a lower cutoff of the distribution of line widths from which the temperature is derived. We carefully test the accuracy of this technique to recover the gas temperature with a hydrodynamic simulation. The temperature at redshift z=(3.9, 3.0, 2.4) is best determined at densities slightly above the mean: T_star=(20200\pm2700, 20200\pm1300, 22600\pm1900)K (statistical error bars) for gas density (in units of the mean density) Delta_star=(1.42\pm0.08, 1.37\pm0.11, 1.66\pm0.11). The power-law index of the temperature-density relation, defined by T=T_star(Delta/Delta_star)^{gamma-1}, is gamma-1= (0.43\pm0.45, 0.29\pm0.30, 0.52\pm0.14) for the same three redshifts. The temperature at the fixed over-density Delta=1.4 is T_1.4=(20100\pm2800, 20300\pm1400, 20700\pm1900)K. These temperatures are higher than expected for photoionized gas in ionization equilibrium with a cosmic background, and can be explained by a gradual additional heating due to on-going HeII reionization. The measurement of the temperature reduces one source of uncertainty in the lower limit to the baryon density implied by the observed mean flux decrement. We find that the temperature cannot be reliably measured for under-dense gas, because the velocities due to expansion always dominate the widths of the corresponding weak lines.Comment: submitted to Ap