4,836 research outputs found
Targeted photodynamic therapy of breast cancer cells using antibody–phthalocyanine–gold nanoparticle conjugates
Public health implications of metals concentrations from prescribed burns: A study adjacent to the Perth metropolitan area.
Ash is not a homogenous product. It is the solid residue of combustion and contains a complex mixture of chemical products. The ash residue resulting from fires varies and is dependent on its source, and burn characteristics such as the temperature of the fire. Ash comprises particles of carbon, soot and trace elements. Ash presents public health risk to people and communities, through direct and indirect ingestion and inhalation. The health effects of ash exposure are not limited to symptoms affecting the eyes, throat and lungs. They can contribute to chronic disease and increase the risk of cancer. The purpose of this study was to evaluate the public health implications of controlled burns in the Darling Escarpment, adjacent to Perth’s metropolitan area in Western Australia. Concentrations of metals in unburnt vegetative litter and ash (post burn), stratified by size fraction, were determined to assess the potential mobilisation of metals caused by prescribed burns and the potential public health implications associated with burns. These data can also be used in predictive modelling to ascertain the amount of metals likely to be released per hectare when authorities plan future burns in the area.  Ash samples were collected immediately following the fire to capture fine material before it was blown away. The ash samples were separated into size fractions to investigate whether there are differences within each sub sample. Australia’s National Environmental Protection Measures were used to establish whether the metal concentrations were above designated thresholds for health and environmental investigation, these being the recognised levels above which metals are deemed to pose a risk to public (or environmental) health.  Vegetation and ash samples were collected from three sites immediately after the prescribed burn. Samples were analysed for thirteen (13) metals with nine (9) showing statistically significant increases in concentrations in vegetation as compared to ash. The percentages of metals are higher in ash than in vegetative ground litter. The metals identified are Manganese - Vegetation (158.3 ± 89.3 mg/kg), Ash (442.2 ± 462.6 mg/kg); Barium - Vegetation (19.4 ± 25.3 mg/kg); Ash (41.8 ± 62.7 mg/kg); Zinc - Vegetation (15.3 ± 9.7 mg/kg), Ash (25.6 ± 29.7 mg/kg); Vanadium - Vegetation (31.0 mg/kg ± 76.3 mg/kg), Ash (32.2 mg/kg ± 51.0 mg/kg); Copper - Vegetation (4.2 ± 1.5 mg/kg), Ash (10.9 ± 9.8 mg/kg); Chromium (Total) - Vegetation (8.3 ± 15.6 mg/kg), Ash (9.6 ± 12.4 mg/kg); Lead - Vegetation (6.1 ± 8.3 mg/kg), Ash (12.2 ± 8.5 mg/kg); Nickel - Vegetation (2.2 ± 2.2 mg/kg), Ash (4.7 ± 4.4mg/kg) and Cadmium - Vegetation (0.6 ± 0.9 mg/kg), Ash (0.6 ± 0.9 mg/kg). The ash samples were sieved through three aperture’s (2-4 mm, 1-2 mm, <1 mm) to stratify the samples by size fraction and concentrations in all but three of the metals increased as the ash size decreased.It was demonstrated that the level of metal present within the ash samples did not exceed health investigation levels and, with the exception of Manganese, and did not exceed environmental investigations levels. Metals were unlikely to pose a risk if left insitu. However, modelling estimated the volume of metal released and it was determined that metals can pose a subsequent risk if mobilised by wind or water. The likelihood of such mobilisation is high and this finding therefore has public health implications for surrounding communities that are subjected to increases in their exposure to metals, associated with bushfires.The findings from this study contribute to the management of prescribed burns by providing a better understanding of the composition of ash and the effects of potential distribution via aerial deposition or runoff. Data from this study can be used to do predictive modelling of heavy metal mobilisation that may result from burns of similar vegetation environments. This becomes particularly significant where burns are conducted in water catchment areasÂ
Efficacy of B-cell-targeted therapy with rituximab in patients with rheumatoid arthritis.
BACKGROUND: An open-label study indicated that selective depletion of B cells with the use of rituximab led to sustained clinical improvements for patients with rheumatoid arthritis. To confirm these observations, we conducted a randomized, double-blind, controlled study. METHODS: We randomly assigned 161 patients who had active rheumatoid arthritis despite treatment with methotrexate to receive one of four treatments: oral methotrexate (> or =10 mg per week) (control); rituximab (1000 mg on days 1 and 15); rituximab plus cyclophosphamide (750 mg on days 3 and 17); or rituximab plus methotrexate. Responses defined according to the criteria of the American College of Rheumatology (ACR) and the European League against Rheumatism (EULAR) were assessed at week 24 (primary analyses) and week 48 (exploratory analyses). RESULTS: At week 24, the proportion of patients with 50 percent improvement in disease symptoms according to the ACR criteria, the primary end point, was significantly greater with the rituximab-methotrexate combination (43 percent, P=0.005) and the rituximab-cyclophosphamide combination (41 percent, P=0.005) than with methotrexate alone (13 percent). In all groups treated with rituximab, a significantly higher proportion of patients had a 20 percent improvement in disease symptoms according to the ACR criteria (65 to 76 percent vs. 38 percent, P< or =0.025) or had EULAR responses (83 to 85 percent vs. 50 percent, P< or =0.004). All ACR responses were maintained at week 48 in the rituximab-methotrexate group. The majority of adverse events occurred with the first rituximab infusion: at 24 weeks, serious infections occurred in one patient (2.5 percent) in the control group and in four patients (3.3 percent) in the rituximab groups. Peripheral-blood immunoglobulin concentrations remained within normal ranges. CONCLUSIONS: In patients with active rheumatoid arthritis despite methotrexate treatment, a single course of two infusions of rituximab, alone or in combination with either cyclophosphamide or continued methotrexate, provided significant improvement in disease symptoms at both weeks 24 and 48
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Emissions from village cookstoves in Haryana, India, and their potential impacts on air quality
Air quality in rural India is impacted by residential cooking and heating with biomass fuels. In this study, emissions of CO, CO2, and 76 volatile organic compounds (VOCs) and fine particulate matter (PM2.5) were quantified to better understand the relationship between cook fire emissions and ambient ozone and secondary organic aerosol (SOA) formation. Cooking was carried out by a local cook, and traditional dishes were prepared on locally built chulha or angithi cookstoves using brushwood or dung fuels. Cook fire emissions were collected throughout the cooking event in a Kynar bag (VOCs) and on polytetrafluoroethylene (PTFE) filters (PM2.5). Gas samples were transferred from a Kynar bag to previously evacuated stainless-steel canisters and analyzed using gas chromatography coupled to flame ionization, electron capture, and mass spectrometry detectors. VOC emission factors were calculated from the measured mixing ratios using the carbon-balance method, which assumes that all carbon in the fuel is converted to CO2, CO, VOCs, and PM2.5 when the fuel is burned. Filter samples were weighed to calculate PM2.5 emission factors. Dung fuels and angithi cookstoves resulted in significantly higher emissions of most VOCs (p < 0.05). Utilizing dung-angithi cook fires resulted in twice as much of the measured VOCs compared to dung-chulha and 4 times as much as brushwood-chulha, with 84.0, 43.2, and 17.2g measured VOCkgg fuel carbon, respectively. This matches expectations, as the use of dung fuels and angithi cookstoves results in lower modified combustion efficiencies compared to brushwood fuels and chulha cookstoves. Alkynes and benzene were exceptions and had significantly higher emissions when cooking using a chulha as opposed to an angithi with dung fuel (for example, benzene emission factors were 3.18gkgg fuel carbon for dung-chulha and 2.38gkgg fuel carbon for dung-angithi). This study estimated that 3 times as much SOA and ozone in the maximum incremental reactivity (MIR) regime may be produced from dung-chulha as opposed to brushwood-chulha cook fires. Aromatic compounds dominated as SOA precursors from all types of cook fires, but benzene was responsible for the majority of SOA formation potential from all chulha cook fire VOCs, while substituted aromatics were more important for dung-angithi. Future studies should investigate benzene exposures from different stove and fuel combinations and model SOA formation from cook fire VOCs to verify public health and air quality impacts from cook fires
A systems approach to understanding the connection between farm systems resilience and pasture resilience
Farm systems resilience in New Zealand pasture-based farming is influenced by external drivers such as environmental regulation, and internal drivers such as existence, expressed as profitability. We examine ten published case studies of farm systems change to provide insight into management interventions to these drivers and their impacts on pasture resilience. Nutrient supply was key to increasing pasture longevity, water use efficiency and animal feed supply. Manipulating water use efficiency through irrigation and legume (predominantly lucerne) use increased nitrogen use efficiency and added pasture supply for animal consumption. Monitoring the pasture supply and animal response ensured both animal feed requirements and pasture conditions for future growth were met. The resilience of pastures was improved when monitoring guided adaptive management application to ensure whole-farm resilience
Parent-Child Relationships in Early Learning.
Parental behavior during a child’s first five years of life is critical for the development of important social and cognitive outcomes in children that set the stage for life-long adaptation and functioning. This chapter will review some of the key findings about the importance of parent-child relationships in early learning. Three dimensions of parent behavior will be described as “parental engagement”: (a) warmth and sensitivity, (b) support for a child’s emerging autonomy, and (c) active participation in learning. Cross cultural variations in which the styles of these behaviors are expressed are also considered, contrasting physical, social, and cognitive styles of communicating parental care
The Development and Validation of the Diversity Dispositions Index
The population of the U.S. is becoming increasingly more diverse. Yet, administrators and teachers in the U.S. are predominantly European Americans from middle-class backgrounds who speak only English. Many of their students are racial and ethnic minorities, live in poverty, and speak a first language other than English (Banks et aI., 2005, p. 237). The No Child Left Behind Act signed into law in2002 requires school districts to hire highly qualified teachers who possess the necessary dispositions to ensure that all children learn (Center on Education Policy, 2002). School administrators and teachers must understand students\u27 backgrounds and experiences, and they must possess the necessary dispositions to work with students from diverse backgrounds (Villegas & Lucas, 2007)
Managing knowledge transfer partnership for a rural community: the outcomes at Wirksworth, UK
Purpose – This paper aims to propose a knowledge transfer partnership (KTP) model, using higher education (HE) students researching in the UK. It is focused on community engagement via charitable trusts, New Opportunities Wirksworth (NOW) & Ecclesbourne Valley Rail (EVR). The researchers designed and implemented a pilot study that explored the potential of a small, yet attractive and active, market town to diversify and regenerate using tourism. This project, which has been funded by the UK Higher Education Innovation Fund (HEIF), has been devised to operate and monitor a KTP in the culturally important heritage market town of Wirksworth, in Derbyshire. Design/methodology/approach – A systems-thinking constructivist approach is used and employs problem-based learning (PBL) through engagement of students in research and data collection. The authors identified that skills for sustainable development within the community are dependent on the reintegration of complex, inter-dependent and inter-disciplinary factors. A holistic approach to the learning and knowledge shared within the community underpins UK initiatives to promote capacity development in ways to change knowledge applications across product and service boundaries. Therefore, in addition to encouraging diversification and regeneration through tourism, this project supported the University of Derby's academic agenda to promote experiential and entrepreneurial learning in students working at both undergraduate and postgraduate levels. This paper accords with the current university initiatives to meet the student employability agenda through the application of PBL and knowledge management. Findings – The creation of outcomes and recommendations for Wirksworth's stakeholders provides sustainability through the knowledge creation and sharing processes. There are seven outcomes that chart a path to development and knowledge transfer (KT) and sharing. The authors simultaneously provided an environment for students to gain skills and a community to acquire new knowledge, and these are the outcomes and output of this project. New learning styles may support inclusive academic practice (see related samples of PBL such as Ineson and Beresford in HLST resources 2001). Implications for building a KT community through the social capital accumulated in the project are explored. Originality/value – In taking PBL from the classroom to the community, the authors have created a new KT environment in which skills can be acquired and a regeneration strategy can be tested in a work-or-practice-related setting. Students recognise that they are building learning for themselves that is unique in that it cannot be recreated in a classroom setting. The authors see this project developing into a robust long-term partnership between communities and institutions with KT benefits to teaching staff in addition to students. These benefits will include new skills for PBL, working collaboratively with partners in the community to develop key skills in HE students, innovation in assessment, inclusive learning and teaching, experiential and entrepreneurial learning in practice
University Student Descriptions of Their Financial Knowledge of Student Loan Debt
University students and university personnel are important contributors to the economy of the United States regarding excessive student loan debt. As such, a lack of financial literacy is a significant problem. The purpose of this single descriptive qualitative case study was to describe the experiences of certain individual university students about their financial knowledge of their student loan debt. Bandura\u27s social learning theory and Maslow\u27s hierarchy of needs theory was used to analyze the results of this study. The research questions asked how university students describe their experiences regarding student loan debt and their financial acuity, and how do university students’ parents describe their experiences with student loan debt? This study examined students\u27 perceptions and experiences regarding financial literacy and money management related to student loan debt. Data for this study included interviews with 10 borrowers, one college financial counselor, field notes, observations of information available to students on student loans, reviewed reports, and personal journals or diaries on their debt. Open and axial coding revealed five themes: (a) financial skills, (b) budgeting, (c) initial debt, (d) benefits, and (e)challenges. This study could contribute to social change by persuading the implementation of financial literacy training through independent courses or by incorporating lessons into the core curriculum in institutions—similar to this one but using financial knowledge of student loan debt. The study could contribute to financial change by helping university students acknowledge financial challenges; they may alleviate stress and reclaim control of their financial knowledge of student debt and personal lives
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