Children facing economic hardships in the United States

This paper helps document significant improvements in the child low-income rate as well as the significant decrease in the proportion of children who relied on public assistance in the United States during the 1990s. Many disadvantaged groups of children were less likely to live in poor or low-income families in the late 1990s than such children a decade earlier. The improvement in the child low-income rates of these disadvantaged groups was accompanied by a substantial increase in parental employment. However, parental employment appears to do less to protect children from economic hardship than it did a decade earlier. This paper shows that working families’ children in many disadvantaged social groups, especially groups in medium risk ranks--children in families with parents between ages 25 to 29, with parents who only had a high-school diploma, and in father-only families--suffered the largest increase in economic hardship. Our results indicate that the increased odds of falling below low-income lines among children in working families facing multiple disadvantaged characteristics and the increased proportion of these children in various subgroups of working families in the 1990s can help explain the increased economic hardship among subgroups in the medium risk ranks listed above. Finally, the paper also notes that the official measure of poverty tends to underestimate low-income rates.bootstrap, child poverty, employment, income, low income, poverty measure, welfare reform

Decision making improvement by effectively utilising activity-based costing and activity-based management tools

The aim of this study was to suggest ways to effectively utilise Activity-Based Costing and Activity-Based Managment within Eskom Transmission Southern Grid to improve decision making towards improved business and financial performance. The ultimate purpose was to assist managers and staff to implement ABC and ABM effectively for improved business and financial performance. The focus was on the following objective: To suggest ways to effectively utilise ABC & ABM within Eskom Transmission Southern Grid as to improve decision making and business financial performance. Given the selection of management tools available, instruments such as ABC and ABM are usually not implemented alone, but may be supported by one or more approaches. For this reason ABC and ABM are contrasted with several other popular instruments mentioned in the literature. The instruments are: • The value chain; • Continuous improvement; • The theory of constraints; and • Total quality management. Insight will be given to provide managers with more accurate information regarding maintenance for the Grid and tools in identifying critical bottlenecks. By applying the TOC, TQM and continuous improvement strategies, managers will be able to make improved decisions, leading to improved financial performance in the Eskom Transmission Southern Grid. iii The literature study revealed that ABC and ABM prove to be the cornerstone for informed decision making. Since organisations are highly dependent on quality information to make these informed decisions, ABC and ABM reorientate the organisation towards understanding and managing work processes thus impacting financial performance positively. ABC and ABM trace the cost of activities such as engineering and procurement to how maintenance benefits from these activities. The empirical study consisted of a structured questionnaire distributed to a sample population of engineers and managers in Eskom Transmission Southern Grid in Port Elizabeth. It was aimed at gathering information about the use of ABC and ABM within the Grid. Semi-structured interviews were also conducted with financial staff in the Grid and a focus group interview with engineering staff was done. The main findings of the empirical investigation revealed that management and staff lack insight into the use of ABC and ABM and how it can be integrated with existing improvement systems within the organisation. This study is concluded with a number of recommendations. These recommendations address the shortcomings and improvements that can be made to improve the utilisation of ABC and ABM within the organisation. The recommendations address the following: • Ensuring full commitment towards organisational goals and broadening the endorsement of ABC within the organisation; • Highlighting the importance of financial performance throughout the Grid; • Training of Managers, finance staff and engineers is required for proper execution of the ABC system; • Implementers need skills and know-how of the ABC and ABM system ensuring full utilisation; • The main cost drivers are identified, prioritised and efforts channelled into these activities; • Tools such as the Theory Of Constraints and Total Quality Management from the proposed model would assist the Grid in identifying the bottlenecks of a system correctly, thus know explicitly the amount of slack capacity of each activity available during a specific time period

An enabling environment for independent power producers in renewable electricity

The increasing demand for electricity, the rising price of energy from conventional sources and limited electricity supply are a global concern. The demand on electricity generation could be alleviated by diversifying the sources from which electricity is obtained to achieve the goals of long-term electricity supply. Diversification implies finding alternative sources of energy such as renewable energy for the production of electricity. The South African electricity system is under increased pressure to provide and maintain electricity supply to its users. Electricity production may be regarded as a key contributor to the social and economic development of South Africa. The challenges are so serious that it will gradually become increasingly difficult to extract sufficient resources to satisfy increasing electricity demand. Growth in the electricity and industrial sectors signifies profound changes in the entire energy industry. The South African power utility Eskom, supplies 94% of South Africa’s electricity but the risk of inadequate supply because of increasing electricity demand is mitigated through the employment of Independent Power Producers (IPPs) which supply to the grid. However, although a limited number of IPP entrepreneurs sell electricity to the Eskom grid, there is no enabling entrepreneurial environment in which they can thrive. There is no positive movement to inaugurate policies and processes. This has created an opportunity for Smart Grid access as a viable option to accommodate IPP entrepreneurs into the grid. Investing in renewable electricity sources may provide feasible alternatives for the electricity industry, it would alleviate pressure on current supply whilst creating an enabling entrepreneurial environment for IPP entrepreneurs and increase entrepreneurial activity. This study investigates a proposed model for an enabling entrepreneurial environment for IPPs in the RE sector that can be utilised to ensure increased entrepreneurial activity within the electricity industry. Establishing such an enabling environment would contribute positively to the alleviation of the electricity demand crisis, result in lower carbon emissions and create a sustainable, more diverse electricity generation mix. This proposed IPP industry model for an enabling entrepreneurial environment is presented to address the problems experienced at the different levels of the electricity industry. The model can be utilised to increase entrepreneurial activity while eradicating major electricity challenges at different levels in the South African electricity industry. The results indicate that that RE, in the form of solar and wind, has the potential to expand the South African electricity industry significantly. Therefore, in order to reform the South African electricity industry, stakeholders need to embrace entrepreneurship as IPP entrepreneurs. This can be done effectively by the incorporation of IPP entrepreneurs into the electricity network. However, an enabling entrepreneurial environment in which to operate must be ensured. In this study, five important variables support the establishment of an enabling entrepreneurial environment for IPP entrepreneurs. These have been identified as; Smart Grids, Entrepreneurship, Renewable electricity environment, SA policy and Stakeholder theory. An important contribution has been made towards Stakeholder Theory. This has proven to be instrumental within the RE sector of the electricity industry in South Africa, as the mentioned role players have a reciprocal role to play. Three surveys were conducted at three levels of the electricity industry, namely, at organisational, legislative and entrepreneurial levels and included Eskom Management, National Energy Regulator (NERSA) Management and Approved and Non-approved IPPs. Both qualitative and quantitative research methods were utilised in this research study. The results indicate that SA Policy is instrumental in assisting stakeholders to facilitate the IPP process and feed the power from RE generation into the network. Most respondents were positive about the role of Smart Grids in future electricity generation and their contribution towards creating an enabling entrepreneurial environment for IPP entrepreneurs. Respondents indicated that by policy decisions, greater emphasis can be placed on the results of climate change and environmental challenges. Emphasis on the incorporation of stakeholders proved imperative to this group (IPPs). The results indicated that stakeholder management is a key factor contributing to the establishment of an enabling entrepreneurial environment. The major contribution of this study is a proposed entrepreneurial model that can improve future sustainability of the electricity supply

Fire responses by bird guilds and species in heathy dry forests in central Victoria, Australia

Predicted increases in fire frequency and extent are being realised across Australia, bringing changes to the fire regime which may influence the availability of essential resources required by birds. However, few studies have examined either the impacts of fire frequency on birds or the impacts from both wildfire and planned burns, com bined. Birds were surveyed eight times across 84 sites in heathy dry forests in central Victoria, south-east Australia, from 2012 to 2014. Fire history records were retrieved from the 1970’s onwards, the time from which accurate planned burn records were kept. We developed mixed models to investigate how birds responded to time-since-fire and fire frequency, analysing total bird abundance, ten foraging guilds and 30 individual species. We found distinct responses by all modelled guilds and species to time-since-fire, along with evidence for responses to fire frequency. The greatest shifts in species’ abundances occurred during the first ten years post fire, with bird species commonly present across the stages greater than ten years since fire. For total bird abundance there was no statistically detectible difference between recently burnt forest (0-6 months) and other age classes. However, some guilds showed a significant drop in abundance in newly burnt vegetation (e.g. bark foragers, damp ground insectivores, those that feed on seeds close to the ground, tall shrub foragers). It is with guild and species’ responses that more differences across vegetation age classes became apparent. Significant increases in abundance were apparent in both the regrowth and new growth vegetation age classes, compared with older habitat (e.g. canopy foragers, damp ground insectivores, tall shrub foragers); open ground foragers were especially common in post-fire regrowth but then significantly declined. Other responses were more complex, with species’ preferences reflecting their foraging ecology. Some birds showed preferences across two age classes: sites that were young post-fire regrowth (6 months–2.5 years since fire) along with sites of old habitat (>35 years since fire), (e.g. Crimson Rosella, Scarlet Robin, Sulphur-crested Cockatoo), while some ground-foraging species became scarce in dense new-growth vegetation that appears 2.5–10 years post fire (e.g. Australian Magpie, Laughing Kookaburra and White-winged Chough). Such species may deserve specific management strategies to maintain populations in forests where substantial areas are burnt by wildfire or planned burns, over short periods of time. The model for total bird abundance showed a significant fire frequency response with birds preferring sites twice burnt within 35 years (e.g. bark and canopy-foraging guilds). Four guilds demonstrated a preference for sites frequently burnt, increasing in abundance as number of burns increased (nectarivores, open-ground foragers, seeds in trees foragers, tall shrub foragers). In contrast, two species appeared to prefer sites that had experienced low fire frequencies, a response not common to their guilds. Laughing Kookaburra (carnivore) and White-winged Chough (forages on open ground among trees) generally declined in abundance with increasing fire frequency. © 2023 Elsevier B.V

Living at the Edge: American Low-Income Children and Families

By analyzing data from the Current Population Survey March Supplements, Living at the Edge explores the following questions about children in low-income families in the United States: What are the overall changes in the low-income and poverty rates for children over the past quarter century? How has the population of children in low-income families changed over the past decade? Which children are more likely to live in low-income families? How have changes in parental employment status affected the likelihood of children living in low-income families? What are the state by state variations in child low-income and poverty rates, and how have these changed in the last decade? How does a more inclusive definition of family income and expenses affect our understanding of the poverty and near-poverty rates of children in low-income families? This report helps document significant improvements in the child low-income rate as well as the significant decrease in the proportion of children who relied on public assistance during the 1990s. However, Living at the Edge also finds a notable increase in the share of children who lived in near-poor families (those with incomes between 100 and 200 percent of the poverty line) among children in low-income families during the 1990s. Many disadvantaged groups of children, including those with young parents, minority parents, parents with limited education, or unmarried parents, were less likely to live in poor or low-income families in the late 1990s than such children a decade earlier. The improvement in the child low-income rates of these disadvantaged groups was closely related to an increase in parental employment during the late 1990s. However, the low-income rate worsened for children whose more educated parent had a high-school diploma but no college education. For children of many disadvantaged social groups, parental employment appears to do less to protect them from economic hardship then it did a decade earlier. The groups that suffered the most in reduced economic security given parental employment status were those in the medium risk ranks (children in families with at least one parent between ages 25 to 39, children whose more educated parent had only has a high school diploma, and in father-only families). The report also notes that the official measure of poverty ignores the burden of medical and work related expenses as well as taxes and therefore tends to underestimate the share of children in near-poor and low-income families facing economic insecurity. Finally, we discuss the policy implications for our findings

GBRDs over groups of orders ≤100 or of order pq with p, q primes

AbstractThere are well-known necessary conditions for the existence of a generalized Bhaskar Rao design over a group G, with block size k=3. It has been conjectured that these necessary conditions are indeed sufficient. We prove that they are sufficient for groups G of order pq where p,q are primes and for groups of all orders ≤100 except possibly 32, 36, 48, 54, 60, 64, 72, 96

The Ess/Type VII secretion system of Staphylococcus aureus shows unexpected genetic diversity

We thank the core sequencing and informatics teams at the Sanger Institute for their assistance and The Wellcome Trust for its support of the Sanger Institute Pathogen Genomics and Biology groups. SRH, JP and MTGH were supported by Wellcome Trust grant 098051. Bioinformatics and Computational Biology analyses were supported by the University of St Andrews Bioinformatics Unit that is funded by a Wellcome Trust ISSF award (grant 105621/Z/14/Z). SP is funded by the UKCRC Translational Infection Research Initiative, and the NIHR Cambridge Biomedical Research Centre. CPH is supported by the Wellcome Trust (grant number 104241/z/14/z) TP is a Royal Society/Wolfson Merit Award Holder.BACKGROUND: Type VII protein secretion (T7SS) is a specialised system for excreting extracellular proteins across bacterial cell membranes and has been associated with virulence in Staphylococcus aureus. The genetic diversity of the ess locus, which encodes the T7SS, and the functions of proteins encoded within it are poorly understood. RESULTS: We used whole genome sequence data from 153 isolates representative of the diversity of the species to investigate the genetic variability of T7SS across S. aureus. The ess loci were found to comprise of four distinct modules based on gene content and relative conservation. Modules 1 and 4, comprising of the 5' and 3' modules of the ess locus, contained the most conserved clusters of genes across the species. Module 1 contained genes encoding the secreted protein EsxA, and the EsaAB and EssAB components of the T7SS machinery, and Module 4 contained two functionally uncharacterized conserved membrane proteins. Across the species four variants of Module 2 were identified containing the essC gene, each of which was associated with a specific group of downstream genes. The most diverse module of the ess locus was Module 3 comprising a highly variable arrangement of hypothetical proteins. RNA-Seq was performed on representatives of the four Module 2 variants and demonstrated strain-specific differences in the levels of transcription in the conserved Module 1 components and transcriptional linkage Module 2, and provided evidence of the expression of genes the variable regions of the ess loci. CONCLUSIONS: The ess locus of S. aureus exhibits modularity and organisational variation across the species and transcriptional variation. In silico analysis of ess loci encoded hypothetical proteins identified potential novel secreted substrates for the T7SS. The considerable variety in operon arrangement between otherwise closely related isolates provides strong evidence for recombination at this locus. Comparison of these recombination regions with each other, and with the genomes of other Staphylococcal species, failed to identify evidence of intra- and inter-species recombination, however the analysis identified a novel T7SS in another pathogenic staphylococci, Staphylococcus lugdunensis.Publisher PDFPeer reviewe

Study protocol : the empirical investigation of methods to correct for measurement error in biobanks with dietary assessment

Peer reviewedPublisher PD

Subglacial controls on dynamic thinning at Trinity-Wykeham Glacier, Prince of Wales Ice Field, Canadian Arctic

Mass loss from glaciers and ice caps represents the largest terrestrial component of current sea level rise. However, our understanding of how the processes governing mass loss will respond to climate warming remains incomplete. This study explores the relationship between surface elevation changes (dh/dt), glacier velocity changes (du/dt), and bedrock topography at the Trinity-Wykeham Glacier system (TWG), Canadian High Arctic, using a range of satellite and airborne datasets. We use measurements of dh/dt from ICESat (2003-2009) and CryoSat-2 (2010-2016) repeat observations to show that rates of surface lowering increased from 4 m yr-1 to 6 m yr-1 across the lowermost 10 km of the TWG. We show that surface flow rates at both Trinity Glacier and Wykeham Glacier doubled over 16 years, during which time the ice front retreated 4.45 km. The combination of thinning, acceleration and retreat of the TWG suggests that a dynamic thinning mechanism is responsible for the observed changes, and we suggest that both glaciers have transitioned from fully grounded to partially floating. Furthermore, by comparing the separate glacier troughs we suggest that the dynamic changes are modulated by both lateral friction from the valley sides and the complex geometry of the bed. Further, the presence of bedrock ridges induces crevassing on the surface and provides a direct link for surface meltwater to reach the bed. We observe supraglacial lakes that drain at the end of summer and are concurrent with a reduction in glacier velocity, suggesting hydrological connections between the surface and the bed significantly impact ice flow. The bedrock topography thus has a primary influence on the nature of the changes in ice dynamics observed over the last decade.</p