255 research outputs found

    Urban-rural contrasts in Arbor Week in South Africa

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    Trees provide people with environmental benefits. Greening projects have been implemented worldwide, but many of them have frustratingly low participation levels. In South Africa, tree-planting campaigns such as the national Arbor Week are generally aimed at schools. Because of the remoteness of rural schools, there are urban / rural disparities in standards of education, infrastructure and support provided at schools, and hence we hypothesized that these disparities would be mirrored in tree-planting activities associated with national Arbor Week. In the study reported here, 236 urban and rural schools were assessed by means of postal surveys and subsampled via direct interviews, as to their participation in Arbor Week activities, the provision of trees, constraints to participation, and the perceived benefits of planting trees. Very few urban schools had never participated in any Arbor Week activities, whereas one-fifth of rural ones had never participated in any way. Urban schools participated in a greater number of Arbor Week activities than rural schools, including tree-planting, displaying posters and having speeches. Thus, overall information about Arbor Week is lacking in rural areas compared to urban ones. Rural schools derived more benefits from planting trees, with shade and education being the primary benefits overall. Rural schools were supplied with trees by NGOs, whereas urban schools received trees from individual or company donations. The major constraints to tree-planting are livestock damage, water shortages, vandalism and theft. These obstacles need to be addressed in a holistic fashion in order to improve the participation and success of National Arbor Week as a vehicle for tree-planting and environmental awareness

    Effect of Preventive Primary Care Outreach on Health Related Quality of Life Among Older Adults at Risk of Functional Decline: Randomised Controlled Trial

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    Objective: To evaluate the impact of a provider initiated primary care outreach intervention compared with usual care among older adults at risk of functional decline. Design: Randomised controlled trial. Setting: Patients enrolled with 35 family physicians in five primary care networks in Hamilton, Ontario, Canada. Participants: Patients were eligible if they were 75 years of age or older and were not receiving home care services. Of 3166 potentially eligible patients, 2662 (84%) completed the validated postal questionnaire used to determine risk of functional decline. Of 1724 patients who met the risk criteria, 769 (45%) agreed to participate and 719 were randomised. Intervention: The 12 month intervention, provided by experienced home care nurses in 2004-6, consisted of a comprehensive initial assessment using the resident assessment instrument for home care; collaborative care planning with patients, their families, and family physicians; health promotion; and referral to community health and social support services. Main outcome measures: Quality adjusted life years (QALYs), use and costs of health and social services, functional status, self rated health, and mortality. Results: The mean difference in QALYs between intervention and control patients during the study period was not statistically significant (0.017, 95% confidence interval ?0.022 to 0.056; P=0.388). The mean difference in overall cost of prescription drugs and services between the intervention and control groups was not statistically significant, (-C165(£107;118;C165 (£107; 118; 162), 95% confidence interval -C16545toC16 545 to $16 214; P=0.984). Changes over 12 months in functional status and self rated health were not significantly different between the intervention and control groups. Ten patients died in each group. Conclusions: The results of this study do not support adoption of this preventive primary care intervention for this target population of high risk older adults

    Pleistocene, Holocene and Recent Bird Gastroliths from Interior Alaska

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    Describes and discusses the origin of polished and rounded grains of quartz, secondary quartz, and chert from (probably) Holocene loess of Easter Egg Hill near Livengood townsite, peat on the Nenana Road, and redeposited Wisconsin loess from the Eva Creek Mine and Ready Bullion Creek Mine at 64 51 N, 148 02 W. The association of these grains with dull, angular grains of the same materials rules out soil or solifluction abrasion in place. Gizzard-bearing birds such as ptarmigan and grouse in Alaska produce glossy polish on their gizzard stones (gastroliths) comparable to that of the Pleistocene and Holocene gastroliths; the polish and roundness of the stones in living birds are more pronounced in late winter. Because the modal size classes of ancient and Recent polished gastroliths do not coincide, some of the ancient gastroliths are believed to have been produced by birds not now living in interior Alaska.Gastrolithes d'oiseaux pléistocènes, holocènes et récents de l'Alaska intérieur. On trouve dans le loess et la tourbe de l'Alaska intérieur des grains polis et arrondis de quartz, de quartz secondaire et de chert. Le diamètre intermédiaire de ces grains se situe entre 35 et 0.07 mm, les plus abondants mesurant 0.07 mm, de 2 à 4 mm et peut-être, de 10 à 20 mm. Le poli de ces grains est le produit de l'abrasion dans des gésiers d'oiseaux. Les oiseaux à gésier qui vivent aujourd'hui dans l'Alaska intérieur produisent sur leurs gastrolithes un fini poli comparable à celui des gastrolithes des dépôts holocènes et pléistocènes. Sur les gastrolithes d'oiseaux récents, le poli et l'arrondi varient directement, atteignant un maximum pour les oiseaux vivants à la fin de l'hiver. On peut croire que certaines gastrolithes polies de l'Holocène et du Pléistocène ont été produites par des oiseaux qui ne vivent plus aujourd'hui dans l'Alaska intérieur, car les classes dimensionnelles de ces gastrolithes anciennes ne coïncident plus avec celles des gastrolithes des oiseaux d'aujourd'hui

    Fast two-dimensional model

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    A two dimensional (altitude and latitude) model of the atmosphere is used to investigate problems relating to the variability of the dynamics and temperature of the atmosphere on the ozone distribution, solar cycle variations of atmospheric constituents, the sensitivity of model results to tropospheric trace gas sources, and assessment computations of changes in ozone related to manmade influences. In a comparison between two dimensional model results in which the odd nitrogen family was transported together and model results in which the odd nitrogen species was transported separately, it was found that the family approximations are adequate for perturbation scenario calculations

    Long-term survival of olfactory sensory neurons after target depletion.

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    Life-long addition and elimination of neurons within the adult olfactory epithelium and olfactory bulb allows for adaptive structural responses to sensory experience, learning, and recovery after injury. The interdependence of the two structures is highlighted by the shortened life span of sensory neurons deprived of bulb contact, and has prompted the hypothesis that trophic cues from the bulb contribute to their survival. The specific identity and source of these signals remain unknown. To investigate the potential role of target neurons in this support, we employed a neurotoxic lesion to selectively remove them while preserving the remaining nerve projection pathway, and examined the dynamics of sensory neuron proliferation and survival. Pulse-labeling of progenitors with bromodeoxyuridine showed that, as with surgical bulb removal, increased apoptosis in the epithelium triggered accelerated production of new neurons after chemical depletion of target cells. Rather than undergoing premature death, a large subpopulation of these neurons survived long term. The combination of increased proliferation and extended survival resulted in essentially normal numbers of new sensory neurons surviving for as long as 5 weeks, with an accompanying restoration of olfactory marker protein expression. Changes in neurotrophic factor expression levels as measured by quantitative polymerase chain reaction (Q-PCR), and in bulb cell populations, including the addition of new neurons generated in the subventricular zone, were observed in the injured bulb. These data indicate that olfactory sensory neurons can adapt to reductions in their normal target field by obtaining sufficient support from remaining or alternative cell sources to survive and maintain their projections

    Phase III Prospective Randomized Comparison Trial of Depot Octreotide Plus Interferon Alfa-2b Versus Depot Octreotide Plus Bevacizumab in Patients With Advanced Carcinoid Tumors: SWOG S0518

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    Purpose Treatment options for neuroendocrine tumors (NETs) remain limited. This trial assessed the progression-free survival (PFS) of bevacizumab or interferon alfa-2b (IFN-α-2b) added to octreotide among patients with advanced NETs. Patients and Methods Southwest Oncology Group (SWOG) S0518, a phase III study conducted in a US cooperative group system, enrolled patients with advanced grades 1 and 2 NETs with progressive disease or other poor prognostic features. Patients were randomly assigned to treatment with octreotide LAR 20 mg every 21 days with either bevacizumab 15 mg/kg every 21 days or 5 million units of IFN-α-2b three times per week. The primary end point was centrally assessed PFS. This trial is registered with ClinicalTrials.gov as NCT00569127. Results A total of 427 patients was enrolled, of whom 214 were allocated to bevacizumab and 213 to IFN-α-2b. The median PFS by central review was 16.6 months (95% CI, 12.9 to 19.6 months) in the bevacizumab arm and was 15.4 months (95% CI, 9.6 to 18.6 months) in the IFN arm (hazard ratio [HR], 0.93; 95% CI, 0.73 to 1.18; P = .55). By site review, the median PFS times were 15.4 months (95% CI, 12.6 to 17.2 months) for bevacizumab and 10.6 months (95% CI, 8.5 to 14.4 months) for interferon (HR, 0.90; 95% CI, 0.72 to 1.12; P = .33). Time to treatment failure was longer with bevacizumab than with IFN (HR, 0.72; 95% CI, 0.58 to 0.89; P = .003). Confirmed radiologic response rates were 12% (95% CI, 8% to 18%) for bevacizumab and 4% (95% CI, 2% to 8%) for IFN. Common adverse events with bevacizumab and octreotide included hypertension (32%), proteinuria (9%), and fatigue (7%); with IFN and octreotide, they included fatigue (27%), neutropenia (12%), and nausea (6%). Conclusion No significant differences in PFS were observed between the bevacizumab and IFN arms, which suggests that these agents have similar antitumor activity among patients with advanced NETs

    Evaluation of Serum for Pathophysiological Effects of Prolonged Low Salinity Water Exposure in Displaced Bottlenose Dolphins (Tursiops truncatus)

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    We conducted a retrospective study of serum biochemistry and hematologic findings from displaced, out-of-habitat bottlenose dolphins (Tursiops truncatus) exposed to various low salinity environments in waters along the southern United States including southeastern Atlantic and northern Gulf of Mexico. Serum sodium, chloride, and calculated osmolality were significantly lower and below reference ranges in displaced animals compared to free-ranging case control animals. This suggests clinical hyponatremia, hypochloremia, and hypo-osmolality due to an uptake of low saline water from the environment. In addition, significant differences were found in other serum chemistry variables, although none were outside of normal reference ranges for non-controlled free-ranging animals. Multiple linear regressions demonstrated the degree of salinity had a greater pathophysiologic response than the duration of fresh water exposure. The Na/Cl ratio and bicarbonate were the only variables that were significantly modulated by exposure duration. These findings suggest that the degree of salinity is a critical factor when assessing and managing care for dolphins chronically exposed to low salinity water. Results from this study indicate that changes in various biochemical parameters can be used to determine fresh water exposure and aid in determining the treatment for animals recovered from low salinity waters

    Neutrophils in cancer: neutral no more

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    Neutrophils are indispensable antagonists of microbial infection and facilitators of wound healing. In the cancer setting, a newfound appreciation for neutrophils has come into view. The traditionally held belief that neutrophils are inert bystanders is being challenged by the recent literature. Emerging evidence indicates that tumours manipulate neutrophils, sometimes early in their differentiation process, to create diverse phenotypic and functional polarization states able to alter tumour behaviour. In this Review, we discuss the involvement of neutrophils in cancer initiation and progression, and their potential as clinical biomarkers and therapeutic targets

    Nonlinear gap junctions enable long-distance propagation of pulsating calcium waves in astrocyte networks

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    A new paradigm has recently emerged in brain science whereby communications between glial cells and neuron-glia interactions should be considered together with neurons and their networks to understand higher brain functions. In particular, astrocytes, the main type of glial cells in the cortex, have been shown to communicate with neurons and with each other. They are thought to form a gap-junction-coupled syncytium supporting cell-cell communication via propagating Ca2+ waves. An identified mode of propagation is based on cytoplasm-to-cytoplasm transport of inositol trisphosphate (IP3) through gap junctions that locally trigger Ca2+ pulses via IP3-dependent Ca2+-induced Ca2+ release. It is, however, currently unknown whether this intracellular route is able to support the propagation of long-distance regenerative Ca2+ waves or is restricted to short-distance signaling. Furthermore, the influence of the intracellular signaling dynamics on intercellular propagation remains to be understood. In this work, we propose a model of the gap-junctional route for intercellular Ca2+ wave propagation in astrocytes showing that: (1) long-distance regenerative signaling requires nonlinear coupling in the gap junctions, and (2) even with nonlinear gap junctions, long-distance regenerative signaling is favored when the internal Ca2+ dynamics implements frequency modulation-encoding oscillations with pulsating dynamics, while amplitude modulation-encoding dynamics tends to restrict the propagation range. As a result, spatially heterogeneous molecular properties and/or weak couplings are shown to give rise to rich spatiotemporal dynamics that support complex propagation behaviors. These results shed new light on the mechanisms implicated in the propagation of Ca2+ waves across astrocytes and precise the conditions under which glial cells may participate in information processing in the brain.Comment: Article: 30 pages, 7 figures. Supplementary Material: 11 pages, 6 figure
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