Observations of Global and Local Infall in NGC 1333

We report ``infall asymmetry'' in the HCO$^+$ (1--0) and (3--2) lines toward NGC 1333, extended over $\sim 0.39 {\rm pc}^2$, a larger extent than has been reported be fore, for any star-forming region. The infall asymmetry extends over a major portion of the star-forming complex, and is not limited to a single protostar, or to a single dense core, or to a single spectral line. It seems likely that the infall asymmetry represents inward motions, and that these motions are physically associated with the complex. Both blue-asymmetric and red-asymmetric lines are seen, but in both the (3--2) and (1--0) lines of HCO$^+$ the vast majority of the asymmetric lines are blue, indicating inward motions. The (3--2) line, tracing denser gas, has the spectra with the strongest asymmetry and these spectra are associated with the protostars IRAS 4A and 4B, which most likely indicates a warm central source is affecting the line profiles. The (3--2) and (1--0) lines usually have the same sense of asymmetry in common positions, but their profiles differ significantly, and the (1--0) line appears to trace motions on much larger spatial scales than does the (3--2) line. Line profile models fit the spectra well, but do not strongly constrain their parameters. The mass accretion rate of the inward motions is of order 10$^{-4}$ M$_\odot$/yr, similar to the ratio of stellar mass to cluster age.Comment: 28 pages, 11 figures, 1 colour figur

On the Identification of High Mass Star Forming Regions using IRAS: Contamination by Low-Mass Protostars

We present the results of a survey of a small sample (14) of low-mass protostars (L_IR < 10^3 Lsun) for 6.7 GHz methanol maser emission performed using the ATNF Parkes radio telescope. No new masers were discovered. We find that the lower luminosity limit for maser emission is near 10^3 Lsun, by comparison of the sources in our sample with previously detected methanol maser sources. We examine the IRAS properties of our sample and compare them with sources previously observed for methanol maser emission, almost all of which satisfy the Wood & Churchwell criterion for selecting candidate UCHII regions. We find that about half of our sample satisfy this criterion, and in addition almost all of this subgroup have integrated fluxes between 25 and 60 microns that are similar to sources with detectable methanol maser emission. By identifying a number of low-mass protostars in this work and from the literature that satisfy the Wood & Churchwell criterion for candidate UCHII regions, we show conclusively for the first time that the fainter flux end of their sample is contaminated by lower-mass non-ionizing sources, confirming the suggestion by van der Walt and Ramesh & Sridharan.Comment: 8 pages with 2 figures. Accepted by Ap

THE APPLICATION OF A SPORT-SPECIFIC 3D STEREOSCOPIC STIMULUS TO EXAMINE PRE-PLANNING TIME AND GAZE CHARACTERISTICS DURING EVASIVE SIDE-STEPPING MANOEUVRES

It is well established that anterior cruciate ligament (ACL) injuries are serious, debilitating and costly for an individual, while also creating a significant public health burden at a societal level. ACL injuries occur when inappropriate external loads are applied to the knee and most commonly occur during the performance of a side-stepping (Ssg) manoeuvre (Besier et al., 2001a). Previous laboratory based investigations of evasive Ssg have employed generic light or mannequin visual stimuli in an effort to simulate the time and space constraints experienced by athletes, in the preparation and execution of the Ssg manoeuvre (Besier et al., 2001b; Besier et al., 2003; Mclean et al., 2004). However, a possible outcome of attempts to impose these constraints in lab environments is that the use of unrealistic visual stimuli may not accurately reflect or identify the relationship of the perceptual demands of the task with injury risk variables, during a sidestep in game based situations. This study proposes that the presentation of a three dimensional (3D) stereoscopic stimulus (3DSS), featuring a 3D video based sport specific reconstruction of an opposing defender(s) simulating a tackle, may improve the ecological validity of laboratory based investigations. Additionally, the incorporation of the 3DSS tool with eye tracking will allow for the subject’s gaze characteristics (fixations, durations on the 3DSS image) to be assessed. The general aims of this study were to: Technical • develop a 3DSS that delivers realistic sport-specific constraints to footballers during evasive Ssg manoeuvres, • create 3DSS scenarios that incorporate realistic game based variations of imposed time and space constraints (e.g. 3DSS tackle scenarios with one or two defenders), • develop an interface and protocol that integrates the 3DSS system with a commercial eye tracking system (ASL Eye Tracking Recorder), for the purpose of quantifying the lab based subject’s gaze characteristics on the projected stimulus during a Ssg manoeuvre, Experimental • identify differences in biomechanical variables (kinematic, kinetic and neuromuscular) associated with increased injury risk during Ssg manoeuvres, using a traditional light (light emitting diode) based stimulus (LBSS) compared with a 3DSS stimuli

Bougainville Province: Text summaries, maps, code lists and village identification

The major purpose of the Papua New Guinea Agricultural Systems Project is to produce information on small holder (subsistence) agriculture at provincial and national levels (Allen et al 1995). Information was collected by field observation, interviews with villagers and reference to published and unpublished documents. Methods are described by Bourke et al. (1993). This Working Paper contains a written summary of the information on the Agricultural Systems in this Province, maps of the location of agriculture systems, a complete listing of all information in the database in coded form, and lists of villages with National Population Census codes, indexed by agricultural systems. This information is available as a map-linked database (GIS) suitable for use on a personal computer in ESRI and MapInfo formats. An Agricultural System is identified when a set of similar agricultural crops and practices occur within a defined area. Six criteria are used to distinguish one system from another: 1. Fallow type (the vegetation which is cleared from a garden site before cultivation). 2. Fallow period (the length of time a garden site is left unused between cultivations). 3. Cultivation intensity (the number of consecutive crops planted before fallow). 4. The staple, or most important, crops. 5. Garden and crop segregation (the extent to which crops are planted in separate gardens; in separate areas within a garden; or are planted sequentially). 6. Soil fertility maintenance techniques (other than natural regrowth fallows). Where one or more of these factors differs significantly and the differences can be mapped, then a separate system is distinguished. Where variation occurs, but is not able to be mapped at 1:500 000 scale because the areas in which the variation occurs are too small or are widely dispersed within the larger system, a subsystem is identified. Subsystems within an Agricultural System are allocated a separate record in the database, identified by the Agricultural System number and a subsystem number. Sago is a widespread staple food in lowland Papua New Guinea. Sago is produced from palms which are not grown in gardens. Most of the criteria above cannot be applied. In this case, systems are differentiated on the basis of the staple crops only. The Papua New Guinea Resource Information System (PNGRIS) is a GIS which contains information on the natural resources of PNG (Bellamy 1986). PNGRIS contains no information on agricultural practices, other than an assessment of land use intensity based on air photograph interpretation by Saunders (1993. The Agricultural Systems Project is designed to provide detailed information on agricultural practices and cropping patterns as part of an upgraded PNGRIS geographical information system. For this reason the Agricultural Systems database contains almost no information on the environmental settings of the systems, except for altitude and slope. The layout of the text descriptions, the database code files and the village lists are similar to PNGRIS formats (Cuddy 1987). The mapping of Agricultural Systems has been carried out on the same map base and scale as PNGRIS (Tactical Pilotage Charts, 1:500 000). Agricultural Systems were mapped within the areas of agricultural land use established by Saunders (1993) from aerial photography. Except where specifically noted, Agricultural Systems boundaries have been mapped without reference to PNGRIS Resource Mapping Unit (RMU) boundaries. Agricultural Systems are defined at the level of the Province (following PNGRIS) but their wider distribution is recognised in the database by cross-referencing systems which cross provincial borders. A preliminary view of the relationships between PNGRIS RMUs and the Agricultural Systems in this Province can be obtained from the listing of villages by Agricultural System, where RMU numbers are appended. Allen, B. J., R. M. Bourke and R. L. Hide 1995. The sustainability of Papua New Guinea agricultural systems: the conceptual background. Global Environmental Change 5(4): 297-312. Bourke, R. M., R. L. Hide, B. J. Allen, R. Grau, G. S. Humphreys and H. C. Brookfield 1993. Mapping agricultural systems in Papua New Guinea. Population Family Health and Development. T. Taufa and C. Bass. University of Papua New Guinea Press, Port Moresby: 205-224. Bellamy, J. A. and J. R. McAlpine 1995. Papua New Guinea Inventory of Natural Resources, Population Distribution and Land Use Handbook. Commonwealth Scientific and Industrial Research Organisation for the Australian Agency for International Development. PNGRIS Publication No. 6, Canberra. Cuddy, S. M. 1987. Papua New Guinea Inventory of Natural Resources, Population Distribution and Land Use: Code Files Part 1 Natural Resources. Division of Water and Land Resources, Commonwealth Scientific and Industrial Research Organisation and Land Utilization Section, Department of Primary Industry, Papua New Guinea, Canberra

ATCA and Spitzer Observations of the Binary Protostellar Systems CG30 and BHR71

We present interferometric observations with resolution of ~3 arcsecs of the isolated, low-mass protostellar double cores CG30 and BHR71 in the N2$H+(1-0) line and at 3mm dust continuum, using the Australian Telescope Compact Array (ATCA). The results are complemented by infrared data from the Spitzer Space Telescope. In CG30, the 3mm dust continuum images resolve two compact sources with a separation of ~21.7 arcsecs (~8700 AU). In BHR71, strong dust continuum emission is detected at the position of the mid-infrared source IRS1, while only weak emission is detected from the secondary mid-infrared source IRS2. Assuming optically thin 3mm dust continuum emission, we derive hydrogen gas masses of 0.05--2.1$M_\odot$for the four sub-cores. N2H+(1-0) line emission is detected in both CG30 and BHR71, and is spatially associated with the thermal dust continuum emission. We derive the velocity fields and find symmetric velocity gradients in both sources. Assuming that these gradients are due to core rotation, we estimate the specific angular momenta and ratios of rotational energy to gravitational energy for all cores. We also find that the N2H+ emission is strongly affected by the outflows, both in terms of entrainment and molecule destruction.$Spitzer$images show the mid-infrared emission from all four sub-cores. All four sources appear to drive their own outflows. Based on the ATCA and$Spitzer$ observations, we construct spectral energy distributions (SEDs) and derive temperatures and luminosities for all cores. Based on the morphology and velocity structure, we suggest that the sub-cores in CG30 were formed by initial fragmentation of a filamentary prestellar core, while those in BHR71 could originate from rotational fragmentation of a single collapsing protostellar core.Comment: 31 pages, 10 figures, to be published by ApJ in Sep. 200