Analysis of Land Use Change: Theoretical and Modeling Approaches

This Web Book provides information on basic concepts and trends in land use change, and then reviews the state of the art in land use theory and empirical modeling. It concludes by summarizing the main issues pertaining to theories and models of land use change, discusses selected issues in of a more general concern in the context of the analysis of land use change and outlines future research directions.https://researchrepository.wvu.edu/rri-web-book/1000/thumbnail.jp

Glutamine Randomized Studies in Early Life: The Unsolved Riddle of Experimental and Clinical Studies

Glutamine may have benefits during immaturity or critical illness in early life but its effects on outcome end hardpoints are controversial. Our aim was to review randomized studies on glutamine supplementation in pups, infants, and children examining whether glutamine affects outcome. Experimental work has proposed various mechanisms of glutamine action but none of the randomized studies in early life showed any effect on mortality and only a few showed some effect on inflammatory response, organ function, and a trend for infection control. Although apparently safe in animal models (pups), premature infants, and critically ill children, glutamine supplementation does not reduce mortality or late onset sepsis, and its routine use cannot be recommended in these sensitive populations. Large prospectively stratified trials are needed to better define the crucial interrelations of “glutamine-heat shock proteins-stress response” in critical illness and to identify the specific subgroups of premature neonates and critically ill infants or children who may have a greater need for glutamine and who may eventually benefit from its supplementation. The methodological problems noted in the reviewed randomized experimental and clinical trials should be seriously considered in any future well-designed large blinded randomized controlled trial involving glutamine supplementation in critical illness

Standard testing methods for mechanical properties and degradation of low density polyethylene (LDPE) films used as greenhouse covering materials: a critical evaluation

LDPE films are currently the most widespread greenhouse covering material in the countries of the Mediterranean region. Taking into account the size of this market, the effect of the material performance on the greenhouse production as well as the related environmental impact problems arising from its disposal, the standardization of the testing of these materials should have already been achieved. However, there are no standard methods available in the European Union for testing LDPE greenhouse films. Furthermore, for predicting the useful lifetime of such films both the critical effect of the various climatic conditions and the effect of the harsh greenhouse micro-environment on their properties should be taken into account. In this paper the various methods for testing the mechanical properties of greenhouse polyethylene films will be presented and discussed critically. Also, the factors affecting ageing of LDPE used as greenhouse covering are presented, including methods for inducing ageing and testing methods in order to probe ageing

Cytokines and Metabolic Patterns in Pediatric Patients with Critical Illness

It is not known if cytokines, which are cell-derived mediators released during the host immune response to stress, affect metabolic response to stress during critical illness. The aim of this prospective study was to determine whether the metabolic response to stress is related to the inflammatory interleukin-6 (IL-6), 10 (IL-10), and other stress mediators' responses and to assess their relationships with different feeding patterns, nutritional markers, the severity of illness as assessed by the Multiple Organ System Failure (MOSF), the Pediatric Risk of Mortality Score (PRISM), systemic inflammatory response syndrome (SIRS), and mortality in critically ill children. Patients were classified as hypermetabolic, normometabolic, and hypometabolic when the measured resting energy expenditures (REE) were >110%, 90–110% and, <90% of the predicted basal metabolic rate, respectively. The initial predominance of the hypometabolic pattern (48.6%) declined within 1 week of acute stress (20%), and the hypermetabolic patterns dominated only after 2 weeks (60%). Only oxygen consumption (VO2) and carbon dioxide production (VCO2) (P < .0001) but none of the cytokines and nutritional markers, were independently associated with a hypometabolic pattern. REE correlated with the IL-10 but not PRISM. In the presence of SIRS or sepsis, CRP, IL-6, IL-10, Prognostic Inflammatory and Nutritional Index (NI), and triglycerides—but not glucose, VO2, or VCO2 increased significantly. High IL-10 levels (P = .0000) and low measured REE (P = .0000) were independently associated with mortality (11.7%), which was higher in the hypometabolic compared to other metabolic patterns (P < .005). Our results showed that only VO2 and VCO2, but not IL-6 or IL-10, were associated with a hypometabolic pattern which predominated the acute phase of stress, and was associated with increased mortality. Although in SIRS or sepsis, the cytokine response was reliably reflected by increases in NI and triglycerides, it was different from the metabolic (VO2, VCO2) or glucose response

Plastic nets in agriculture ; a general review of types and applications

At the moment, there are a large number of agricultural net types on the market characterized by different structural features such as type of material, type and dimensions of threads, texture, mesh size, porosity / solidity and weight; by radiometric properties like color, transmissivity/reflectivity/shading factor; by physical properties like air permeability and several mechanical characteristics such as tensile stress, strength, elongation at break, and durability. Protection from hail, wind, snow, or strong rainfall in fruit-farming and ornamentals, shading nets for greenhouses and nets moderately modifying the microenvironment for a crop are the most common applications. A systematic review of the current state-of-the-art of structural parameters, standard and regulations, most common agricultural net applications, and their supporting structures has been developed by means of a literature study, technical investigations, concerning characteristics and use of nets. As a result, the survey highlighted that in many cases different, not even similar, net types were adopted for the same application and the same cultivations by various growers. Results show that neither growers nor net producers have clear ideas about the relationship between the net typology optimization for a specific application and the construction parameters of the net. The choice often depends on empirical or economic criteria and not on scientific considerations. Moreover, it appears that scientifically justified technical requirements for nets used in specific agricultural applications have not been established yet

BCG vaccination at three different age groups: response and effectiveness

BACKGROUND: The protection, which some BCG vaccines could confer against the development of tuberculosis (TB) in childhood, might be indirectly reflected by the subsequent development of BCG immune response. The objectives of the study were to examine effectiveness and possible differences of post-vaccination reaction to a lyophilized BCG at different age groups and to evaluate its protection against TB in a decade's period. METHODS: We studied the post-vaccination PPD-skin reaction and scar formation at three different school levels, corresponding to ages of 6, 12 and 15 years old, vaccinated by a lyophilized BCG vaccine (Pasteur Institute), currently used in our country. During a 10-year follow up the reported TB cases in vaccinated and non-vaccinated adolescences up to 24-years old were analyzed and compared to the number of cumulative cases observed in the adult population of two neighboring territories (vaccinated and non-vaccinated). RESULTS AND DISCUSSION: There was a significant correlation (r(2 )= 0.87, p < 0.0001) between tuberculin induration and scar formation. There was no statistically significant difference between the three age groups (6, 12, and 15 year-old, respectively) in regard to the diameter of tuberculin induration or scar formation. Although 34% of 10-year later indurations were unpredictably related to the initial ones (increased or decreased), they were significantly correlated (r(2 )= 0.45, p = 0.009). The relative percentage of TB for the 14–24 years-age group to the adult studied population was significantly lower among the immunized children compared to the non-immunized population of the same age group (17/77, 22% vs. 71/101, 70%, p < .0001). CONCLUSION: Our data suggest that the lyophilized BCG vaccine used for BCG programs at different age groups is equally effective and may confer satisfactory protection against tuberculosis in puberty

Prior antimicrobial therapy in the hospital and other predisposing factors influencing the usage of antibiotics in a pediatric critical care unit

BACKGROUND: The aim of this study was to determine whether prior antimicrobial therapy is an important risk factor for extended antimicrobial therapy among critically ill children. To evaluate other predisposing factors influencing the usage of antibiotics in a pediatric intensive care unit (PICU) setting. To examine the relationship between the extent of antimicrobial treatment and the incidence of nosocomial infections and outcome. METHODS: This prospective observational cohort study was conducted at a university-affiliated teaching hospital (760 beds) in Athens. Clinical data were collected upon admission and on each consecutive PICU day. The primary reason for PICU admission was recorded using a modified classification for mutually exclusive disease categories. All administered antibiotics to the PICU patients were recorded during a six-month period. Microbiological and pharmacological data were also collected over this period. The cumulative per patient and the maximum per day numbers of administered antibiotics, as well as the duration of administration were related to the following factors: Number of antibiotics which the patients were already receiving the day before admission, age groups, place of origin, the severity of illness, the primary disease and its complications during the course of hospitalization, the development of nosocomial infections with positive cultures, the presence of chronic disease or immunodeficiency, various interventional techniques (mechanical ventilation, central catheters), and PICU outcome. RESULTS: During a six-month period 174 patients were admitted to the PICU and received antibiotics for a total of 950 days (62.3% of the length of stay days). While in PICU, 34 patients did not receive antimicrobial treatment (19.5%), 69 received one antibiotic (39.7%), 42 two (24.1%), 17 three (9.8%), and 12 more than three (6.9%). The number of antibiotics prescribed in PICU or at discharge did not differ from that at admission. Indications for receiving antibiotics the day before admission and throughout during hospitalization into PICU were significantly correlated. Although the cumulative number of administered antibiotics did not correlate with mortality (9.8%), it was significantly related to the severity scoring systems PRISM (p < .001), TISS (p < .002) and was significantly related to the number of isolated microorganisms (p < .0001). Multiple regression analysis demonstrated that independent determinants of the cumulative number of antibiotics were: prior administration of antibiotics, presence of a bloodstream infection, positive bronchial cultures, immunodeficiency, and severity of illness. CONCLUSION: Prior antimicrobial therapy should be recognized as an important risk factor for extended antimicrobial therapy among critically ill children. Severity of illness, immunodeficiency, and prolonged length of stay are additional risk factors

Analysis of the effect of perforation on the permeability of biodegradable non-barrier films

AbstractPerforated plastic films are used in Equilibrium Modified Atmosphere Packaging (EMAP) of fresh produce such as fruits and vegetables. The most common material used in such applications is the oriented polypropylene (OPP), which has low permeability with respect to relevant gases, namely water vapor (WV), CO2, and O2. Therefore, the synthesis of the in-package atmosphere is regulated only by the size and number of perforated holes. The replacement of the OPP films with biodegradable ones made of polylactic acid (PLA) or starch based polymers for environmental reasons results into difficulties with respect to designing the EMAP system, since these films are more permeable to the relevant gases and in particular to WV. As a result, the effect of micro-perforation is influenced by the permeability of the film. In the present work, the dependence of the gas flux through perforation on the permeability of the film for the same gas was investigated by experimental and numerical methods. It was shown that the effect of perforation decreases as the permeability of the film increases. The diffusive gas flux through perforation becomes independent of the film permeability, if it is about 100 times smaller than the diffusivity of the studied gas in air

Comparative studies on energy efficiency and GHG emissions between conventional and organic olive groves in Greece and Portugal

Nowadays, traditional farming based on achieving high yields using high inputs, shifts gradu-ally towards maximum possible crop yield using minimal inputs in an optimized way or to-wards organic farming. This is usually accomplishing by low yield of high quality products without using conventional agrochemicals (i.e. fertilizers, pesticides). In general, this last ap-proach leads to lower energy consumption per unit area of land, therefore lower cost and reduced greenhouse gas (GHG) emissions. However, in a global perspective it has the risk of significant total production reduction. Hence, it is vital to consider energy efficiency im-provement, namely the decrease of primary energy consumption for the production of a unit of agricultural product (expressed in weight or volume units), within the farm boundaries. Im-provement of energy efficiency is a key parameter affecting positively the overall efficiency of crop farming systems in terms of energy and GHG emissions. In the present paper, two show cases of olive groves in Greece (“Sterea Ellada” region) and Portugal (“Alentejo” re-gion) were compared to illustrate the effect on energy efficiency and GHG emissions when moving from conventional to organic olive grove cultivations in these different locations. The analysis was based on two simple framework models using information provided by farmers and literature data regarding the inputs and outputs of each olive grove. The models were adjusted according to the olives’ variety, the agricultural practices followed and the location of the production system. Considering the specific energy consumption per unit of product, in the case of the Greek olive grove, organic farming reduces energy consumption by 13.9%, while the final yield is reduced by 30%. GHG emissions are reduced by 58%. In the case of the Portuguese olive grove, organic farming significantly reduces crop yield (54.5%), while, energy efficiency is improved by 9.7% and GHG emissions are reduced by 26%

Generación de residuos sólidos municipales en destinos maduros: un modelo tipo IPAT para Mallorca

[EN] Several studies examined the relationship between environmental degradation and population growth. However, most of them don’t take into account the difference between local population and tourist arrivals. This paper contributes to the literature by separating these two groups within the framework of IPAT-based models to measure the impact of tourist arrivals in terms of municipal solid waste generation for Mallorca. The model leads to a stochastic differential equations system, which showed that this mature tourist destinations have higher population elasticity than industrial economies. Moreover, the model allowed us to measure the elasticity of substitution between lower-income and higher-income tourists.[ES] Varios estudios examinaron la relación entre la degradación ambiental y el crecimiento demográfico. Sin embargo, la mayoría de estos no consideran la diferencia entre población local y turística. Este trabajo contribuye a la literatura mediante la separación de estos grupos en el modelo IPAT para cuantificar el impacto del turismo en la generación de residuos sólidos urbanos en Mallorca. Éste conduce a un sistema estocástico de ecuaciones diferenciales que muestra que destinos maduros tienen mayor elasticidad de población que las economías industriales. Además, el modelo permite medir la elasticidad de sustitución entre turistas de bajos ingresos y de mayores ingresos.The authors would like to mention our gratefulness to TIRME S.A. for their trust, financial support and data source.Arbulú, I.; Lozano, J.; Rey-Maquieira, J. (2013). Municipal solid waste generation in mature destinations: An IPAT-type model for Mallorca. Economía Agraria y Recursos Naturales - Agricultural and Resource Economics. 13(1):69-93. https://doi.org/10.7201/earn.2013.01.04SWORD699313