Temporal introduction patterns of invasive alien plant species to Australia

We examined temporal introduction patterns of 132 invasive alien plant species (IAPS) to Australia since European colonisation in 1770. Introductions of IAPS were high during 1810–1820 (10 species), 1840– 1880 (51 species, 38 of these between 1840 and 1860) and 1930–1940 (9 species). Conspicuously few introductions occurred during 10-year periods directly preceding each introduction peak. Peaks during early European settlement (1810–1820) and human range expansion across the continent (1840-1860) both coincided with considerable growth in Australia’s human population. We suggest that population growth during these times increased the likelihood of introduced plant species becoming invasive as a result of increased colonization and propagule pressure. Deliberate introductions of IAPS (104 species) far outnumbered accidental introductions (28 species) and were particularly prominent during early settlement. Cosmopolitan IAPS (25 species) and those native solely to South America (53 species), Africa (27 species) and Asia (19 species) have been introduced deliberately and accidentally to Australia across a broad period of time. A small number of IAPS, native solely to Europe (5 species) and North America (2 species), were all introduced to Australia prior to 1880. These contrasting findings for native range suggest some role for habitat matching, with similar environmental conditions in Australia potentially driving the proliferation of IAPS native to southern-hemisphere regions. Shrub, tree and vine species dominated IAPS introduced prior to 1840, with no grasses or forbs introduced during early colonisation. Since 1840, all five growth forms have been introduced deliberately and accidentally in relatively large numbers across a broad period of time. In particular, a large number of grass and forb IAPS were deliberately introduced between 1840 and 1860, most likely a direct result of the introduction of legislation promoting intensive agriculture across large areas of the continent. Since the 1980s, only three IAPS have been introduced (all deliberately introduced forbs). The decline in IAPS introductions is most likely a reflection of both increased surveillance and biosecurity efforts and the likelihood that many potential IAPS are still within a pre-expansion lag period

Reich Scholar Program: A Scholarship and Leadership Training Program for International Students with Disabilities at Dartmouth College

National level and international policy changes have emerged to promote educational opportunity for children with disabilities. A gap remains in US higher education in providing access and support for international students with disabilities. Areas of need for this student demographic include financial access, availability of assistive technology, specific socio-cultural advising to living in the US with a disability, comprehensive immigration advising and career support for entering the workforce with a disability. Staff support is generally siloed in colleges. International student services and disability or accessibility services often work in isolation. This capstone imagines the pilot year of a scholarship and leadership training program at Dartmouth College, called the Reich Scholar Program. The pilot year will begin to address the needs of international students with disabilities, empower them with skills to successfully navigate college in the United States, and prepare them for a self-directed personal and professional life following their undergraduate studies. This program will equip staff with a stronger understanding of disability rights and accessibility through their participation in monitoring, evaluation and select program activities. The program vision is to create a campus culture that is more inclusive and empowering to people of all differently-abled identities

Beginning teachers’ perceptions of mentors and access to communities of practice

Purpose – The purpose of this paper is to explore beginning teachers’ perceptions of the role of the mentor in the early stages of developing a professional identity. The beginning teachers in our study are defined as having been awarded qualified teacher status at the end of an initial teacher education programme or having completed their first term as a new teacher with responsibility for a class of pupils. Design/methodology/approach – The research design was a qualitative, inductive study. The concepts of communities of practice, legitimate peripheral participation and power dynamics within a community underpinned this study. The data set was collected over a period of 18 months, through six focus groups and 40 questionnaires with beginning teachers across 34 schools altogether. The data set was analysed using interpretative phenomenological analysis (IPA). Findings – The findings indicated that the ways in which mentors use their power to recognise (or not) the legitimacy of beginning teachers as being part of the school community influences the development of beginning teachers’ professional identities. The thematic analysis of the data indicated the different types of support that mentors may provide: ‘belonging’, ‘emotional’, ‘pedagogical’ and ‘space’. Research limitations/implications – Further research into how mentors perceive their role in supporting new entrants into the profession is needed. Originality/value – These findings are pertinent in England, as the increase in school-based initial teacher training provision will intensify the role of school mentors. These findings will be of value to other countries who are moving towards an increase in school-based teacher training

Sources of Continued Corporate Dominance

How do we make sense of the policy implications of the numerous corporate elites appointed to positions in government? The board interlock network served as a reliable map of power for most of the 20th century. With the decline of the interlock network over the last few decades, we are left without a reliable map of corporate power, leading to a theory of a fractured corporate elite that is ineffectual in its collective policy influence. In this article, we argue that the fractured elite thesis overlooks two factors that counteract the decline of the domestic interlock network- a stable inner circle of highly connected individuals and a growing policy planning network (PPN). Using network data from 2010-11 on both board of director and corporate-policy planning org interlocks, along with a plethora of data on corporate political behavior, we demonstrate that the inner circle is still the primary organizing group of the capitalist class, and that the PPN is its current organizational vehicle. We demonstrate that the PPN is a primary source of political mobilization and cohesion, and is thus a source of continued corporate dominance. Ultimately we argue that the PPN can be used as a map to guide our understanding of the relationship between business and politics

Scheduling Distributed Clusters of Parallel Machines: Primal-Dual and LP-based Approximation Algorithms

The Map-Reduce computing framework rose to prominence with datasets of such size that dozens of machines on a single cluster were needed for individual jobs. As datasets approach the exabyte scale, a single job may need distributed processing not only on multiple machines, but on multiple clusters. We consider a scheduling problem to minimize weighted average completion time of n jobs on m distributed clusters of parallel machines. In keeping with the scale of the problems motivating this work, we assume that (1) each job is divided into m "subjobs" and (2) distinct subjobs of a given job may be processed concurrently. When each cluster is a single machine, this is the NP-Hard concurrent open shop problem. A clear limitation of such a model is that a serial processing assumption sidesteps the issue of how different tasks of a given subjob might be processed in parallel. Our algorithms explicitly model clusters as pools of resources and effectively overcome this issue. Under a variety of parameter settings, we develop two constant factor approximation algorithms for this problem. The first algorithm uses an LP relaxation tailored to this problem from prior work. This LP-based algorithm provides strong performance guarantees. Our second algorithm exploits a surprisingly simple mapping to the special case of one machine per cluster. This mapping-based algorithm is combinatorial and extremely fast. These are the first constant factor approximations for this problem

Incident Tuberculosis among Recent US Immigrants and Exogenous Reinfection

Mathematical models and molecular epidemiologic investigation support the argument that exogenous reinfection plays an important role in tuberculosis transmission in high-incidence regions. We offer additional data from tuberculosis cases among recent US immigrants which strengthen the claim that reinfection in areas of intense transmission is common

Tuberculosis and Poverty: Why Are the Poor at Greater Risk in India?

Background: Although poverty is widely recognized as an important risk factor for tuberculosis (TB) disease, the specific proximal risk factors that mediate this association are less clear. The objective of our study was to investigate the mechanisms by which poverty increases the risk of TB. Methods: Using individual level data from 198,754 people from the 2006 Demographic Health Survey (DHS) for India, we assessed self-reported TB status, TB determinants and household socioeconomic status. We used these data to calculate the population attributable fractions (PAF) for each key TB risk factor based on the prevalence of determinants and estimates of the effect of these risk factors derived from published sources. We conducted a mediation analysis using principal components analysis (PCA) and regression to demonstrate how the association between poverty and TB prevalence is mediated. Results: The prevalence of self-reported TB in the 2006 DHS for India was 545 per 100,000 and ranged from 201 in the highest quintile to 1100 in the lowest quintile. Among those in the poorest population, the PAFs for low body mass index (BMI) and indoor air pollution were 34.2% and 28.5% respectively. The PCA analysis also showed that low BMI had the strongest mediating effect on the association between poverty and prevalent TB (12%, p = 0.019). Conclusion: TB control strategies should be targeted to the poorest populations that are most at risk, and should address the most important determinants of disease—specifically low BMI and indoor air pollution

NebuFlask: Advancing Usability of Nebulizers to Increase Patient Compliance

Nebulizers are ubiquitous in the world of medicine. Any patient diagnosed with asthma, pneumonia, cystic fibrosis, chronic obstructive pulmonary disorder (COPD), or any other severe lung disease often use a nebulizer in order to deliver medication to the lungs. Although these technologies are quite common, they are surprisingly outdated. The most commonly used nebulizers today are bulky, loud, awkward to carry around, and must be plugged into an outlet. These aspects of the nebulizer make it a nuisance to use in general and almost impossible to use outside of the home or clinic. The ultrasonic and mesh nebulizers do address most of these issues, however the cost and maintenance required for these types of nebulizers prevent them from being used popularly. By redesigning the jet nebulizer into a water bottle form with a quieter air compressor, we were able to build a prototype that is lighter, quieter, and more discreet than commercially available nebulizers today. This human-centered design empowers users to nebulize in any setting, effectively increasing patient compliance with prescribed medications