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Effective Vehicle (effective + vehicle)
Selected AbstractsDynamic macroecology on ecological time-scalesGLOBAL ECOLOGY, Issue 1 2010Jonathan A. D. Fisher ABSTRACT Aim, The discipline of macroecology is increasingly being regarded as an effective vehicle for the evaluation of recent population- to ecosystem-level responses to widespread human and environmental influences. However, due to the prevalent use of time-averaged and cumulative data in macroecological analyses, the majority of the patterns that emerge from research in this field can be regarded as static. Here we review the application of dynamic macroecological analyses to changes in relationships between macroecological variables on seasonal to decadal scales. We illustrate the strength of this perspective for documenting changing patterns and testing hypotheses related to these dynamics on ecological time-scales. Location, Studies were compiled and reviewed from terrestrial and aquatic ecosystems. Methods, We review examples of temporal changes in macroecological patterns driven by recent anthropogenic influences and environmental change. Results, The dynamic nature of macroecological patterns on ecological time-scales has been revealed in recent years across a wide range of ecosystems, largely through the development, maintenance and analysis of biotic and environmental monitoring time series. The resultant analyses complement examinations of dynamics over evolutionary time and have similarly revealed that static portrayals can conceal important temporal dynamics that underlie the patterns of interest. As a consequence, static depictions, resting as they do on comparative analyses in which the validity of space-for-time substitutions is assumed, may be of limited use for testing hypotheses related to the mechanisms underlying the patterns revealed and, by extension, the development of reliable predictions of future states. Main conclusions, Recent dynamic macroecological analyses have demonstrated the utility of combined spatial and temporal replication, and have contributed to hypothesis testing related to the mechanistic processes underlying changes in macroecological patterns on ecological time-scales. We suggest four specific avenues of future research to further the development and application of temporal approaches on similar time-scales within the field of macroecology. [source] A decision support methodology for increasing public investment efficiency in Brazilian agrarian reformINTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH, Issue 1 2009Leonardo Melgarejo Abstract The Brazilian Agrarian Reform Program has subsidized the settlement of over 425,000 destitute families on previously unproductive land in what has become a very effective vehicle for social inclusion and productivity growth for those settlers who reach the final stage of the process and receive definitive title to the land. Unfortunately, there is a large difference in efficiency and productivity between more and less successful settlements , fewer than 10% of relocated families have received title and over 25% of them have abandoned the property to which they were assigned. This paper presents a decision support methodology for increasing the efficiency of public investments in agrarian reform that includes a data envelopment analysis model and a mechanism for building consensus among the various constituencies of the agrarian reform process, who not infrequently have conflicting objectives. The OR model described herein uses principal component analysis and data envelopment analysis to identify the most important success factors for relocated families leading to an increase in the chance of both autonomous integration with the market economy and definitive entitlement by these displaced families as well as an increase in the predictability of future settlement success. The model was implemented successfully in Rio Grande do Sul, the southernmost state of Brazil, and was partially used in a pilot project for the countrywide agrarian reform accelerated consolidation program. [source] Unpacking the concept of patient satisfaction: a feminist analysisJOURNAL OF ADVANCED NURSING, Issue 3 2005Sheila A. Turris MSN RN Aim., The aim of this paper is to present a feminist critique of the concept of patient satisfaction. Background., Fiscal restraint, health care restructuring, shifting demographics, biomedical technological advances, and a significant shortage of health care professionals are stretching health care systems across North America to the breaking point. A simultaneous focus on consumerism and health service accountability is placing additional pressure on the system. The concept of patient satisfaction, with roots in the consumer movement of the 1960s, has both practical and political relevance in the current health care system and is commonly used to guide research related to consumer experiences of health care. Because the quality of health care encounters may lead to treatment-seeking delays, patient satisfaction research may be an effective vehicle for addressing this public health issue. However, there is wide agreement that patient satisfaction is an under-theorized concept. Using current conceptualizations of patient satisfaction, we end up all too often producing a checklist approach to ,achieving' patient satisfaction, rather than developing an understanding of the larger issues underlying individual experiences of health care. We focus on the symptoms rather than the problems. Discussion., Without further theoretical refinement, the results of research into patient satisfaction are of limited use. To push forward theoretical development we might apply a variety of theoretical lenses to the analysis of both the concept and the results of patient satisfaction research. Feminism, in particular, offers a perspective that may provoke further refinement of patient satisfaction as a concept. Conclusions., Without a deeper understanding of the values and beliefs (or the worldview) that informs our approaches to researching patient satisfaction, researchers will be reacting to the most obvious indicators and failing to address the underlying issues related to individual experiences of health care. [source] Effects of microcrystalline plant sterol suspension and a powdered plant sterol supplement on hypercholesterolemia in genetically obese Zucker ratsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 12 2003Jari Summanen ABSTRACT Because dietary fat appears to be an effective vehicle for dispensing plant sterols into the diet, a special plant-sterol-containing ingredient has recently been developed. This ingredient is a plant sterol suspension in oil in which the sterols are in microcrystalline form. The objective of the present study was to analyse the cholesterol-lowering effects and safety of two different plant sterol preparations, an orally administered microcrystalline plant sterol suspension (MPS) in rapeseed oil and a powdered plant sterol supplement, in obese Zucker rats. Dietary plant sterol supplements (0.5%, w/w) were given concurrently with a high cholesterol diet (HCD, 1% cholesterol and 18% fat, w/w). No significant changes in serum triglyceride, blood glucose, serum glutamate oxaloacetic transaminase and glutamic pyruvic transaminase values or body and liver weights were observed. The powdered plant sterol supplement lowered the serum cholesterol by 25% (P< 0.05) and the MPS diet by 35% (P< 0.001) compared with HCD by the end of the 12-week experiment. Interestingly, the plant sterol supplements also produced a marked reduction in serum ubiquinone levels, suggesting a possible effect on isoprene synthesis. Unlike the powdered plant sterol, both MPS and plain rape-seed oil decreased the serum baseline diene conjugation values, suggesting that they protect against oxidative stress-induced lipid peroxidation in rats. This lipid peroxidation diminishing effect is probably due to some antioxidative components in rapeseed oil. These findings indicate that an unesterified plant sterol, such as the microcrystalline suspension in oil, effectively prevents cholesterol absorption in obese Zucker rats. [source] Training the trainers: do teaching courses develop teaching skills?MEDICAL EDUCATION, Issue 8 2004Joyce Godfrey Objective, This paper reports on consultants' self-assessed changes in their teaching and training practices over an 8,10-month period. It compares the changes between a group undergoing a 3-day teaching course (participants) and a sample group taken from the course waiting list (controls). Method, A questionnaire listing 18 teaching skills was given to the participants immediately prior to the course and 8,10 months later, and to the controls at the same time intervals. Respondents were asked to rate their ability, frequency of use of each skill, as well as their teaching confidence and effectiveness. Additionally, the second questionnaire asked respondents to identify changes they had made to their teaching. A total of 63% (54) of participants and 51% (23) of controls completed both questionnaires. Changes of 2 + on the rating scales were seen as genuine. The number of such changes was calculated for each individual and on each skill for the 2 groups. Data were analysed using a Mann,Whitney U -test. Results, The majority of course participants reported positive changes in teaching ability on a significantly greater number of skills than did the control group. As a group, changes in ability in 16 of the teaching skills were significantly greater for the participants than for the controls. Increased ability resulted in participants' increased frequency of use of only 4 of the teaching skills. The majority in the participant group reported changes to their teaching. Only a minority in the control group reported such changes. These changes were consistent with course topics and the teaching skills needed to meet General Medical Council recommendations for the education of new doctors. Conclusions, The teaching course is an effective vehicle for increasing consultants' teaching skills. [source] Gene Transfer Strategies for the PhysiologistEXPERIMENTAL PHYSIOLOGY, Issue 6 2000Liang-Fong Wong Foreign genes can be introduced into whole animals using methods of germline transgenesis and somatic gene delivery. While germline transgenesis can generate useful animal models for genetic studies, it can be costly, time-consuming and requires the use of a large number of animals. An alternative means of gene transfer is to deliver genes to somatic cells using non-viral and viral technologies. Non-viral methods such as naked DNA injection, electroporation and liposome/cation lipid-mediated gene transfer are relatively inefficient. In contrast, viruses are effective vehicles that carry foreign genes into a cell rapidly and efficiently. Here we illustrate the usefulness of adenoviral vectors to express a potent and specific inhibitor of cAMP-dependent protein kinase (PKA) to study the role of cyclic 3,,5,-cyclic AMP (cAMP) in the osmotic regulation of the vasopressin gene in a transgenic rat model. The ability to modify endogenous systems within specific cells in a whole animal model allows gene effects to be studied with physiological relevance. The combination of molecular biology and integrative physiology is a powerful application that can aid in the elucidation of how gene function can translate into complex systems in an organism [source] Hollow Mesoporous Zirconia Nanocapsules for Drug DeliveryADVANCED FUNCTIONAL MATERIALS, Issue 15 2010Shaoheng Tang Abstract Hollow mesoporous zirconia nanocapsules (hm -ZrO2) with a hollow core/porous shell structure are demonstrated as effective vehicles for anti-cancer drug delivery. While the highly porous feature of the shell allows the drug, doxorubicin(DOX), to easily pass through between the inner void space and surrounding environment of the particles, the void space in the core endows the nanocapsules with high drug loading capacity. The larger the inner hollow diameter, the higher their DOX loading capacity. A loading of 102% related to the weight of hm -ZrO2 is achieved by the nanocapsules with an inner diameter of 385,nm. Due to their pH-dependent charge nature, hm -ZrO2 loaded DOX exhibit pH-dependent drug releasing kinetics. A lower pH offers a faster DOX release rate from hm -ZrO2. Such a property makes the loaded DOX easily release from the nanocapsules when up-taken by living cells. Although the flow cytometry reveals more uptake of hm -ZrO2 particles by normal cells, hm -ZrO2 loaded DOX release more drugs in cancer cells than in normal cells, leading to more cytotoxicity toward tumor cells and less cytotoxicity to healthy cells than free DOX. [source] Implications of spatial variability of fish assemblages for monitoring of Australia's tropical estuariesAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2010Marcus Sheaves Abstract 1. Although often seen as ideal targets for monitoring environmental change because of their high public profile, fish assemblages rarely appear as indicators in monitoring and reporting. 2. Published data were evaluated to develop a simple approach to quantifying the temporal consistency in assemblage structure suitable for routine monitoring and assessment. Data were examined as catch per unit effort (CPUE) and probability of encounter (PoE), and compared using three approaches with the potential to produce simple indices quantifying the patterns of similarity within an estuary over time: species richness, Bray-Curtis Similarities and a new approach, DeltaPoE. Indices derived from published data were then tested against a time series of data from two estuarine lakes with a history of fish kills. 3. Multidimensional scaling based on PoE emphasizes the temporal consistency of fish assemblages within estuaries at least as well as one based on mean CPUE while providing operational advantages. Similarities based on PoE were more sensitive to change from ,natural' assemblage structure than the simpler indices and showed comparable results with Similarities from (log) CPUE data. The one drawback to Similarities is that their complex statistical formulation often makes them less effective vehicles for reporting and communication. Where this is the case the conceptual simplicity of DeltaPoE and its performance relative to Similarities suggests it is a good candidate from which to develop monitoring indices suitable for routine reporting. 4. The performance of each of the indices were considered against the known fish kills. Species richness tracked the observed changes, an expected outcome in this case because a major impact directly removed species. Both indices based on Similarities also tracked the changes faithfully. Of the two, Similarities based on PoE seemed to react more strongly to assemblage changes. Copyright © 2010 John Wiley & Sons, Ltd. [source] | |||||||||||||