977 resultados para Maine


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This study adapted the current model of science undergraduate research experiences (URE's) and applied this novel modification to include community college students. Numerous researchers have examined the efficacy of URE's in improving undergraduate retention and graduation rates, as well as matriculation rates for graduate programs. However, none have detailed the experience for community college students, and few have employed qualitative methodologies to gather relevant descriptive data from URE participants. This study included perspectives elicited from both non-traditional student participants and the established laboratory community. The purpose of this study was to determine the effectiveness of the traditional model for a non-traditional student population. The research effort described here utilized a qualitative design and an explanatory case study methodology. Six non-traditional students from the Maine Community College System participated in this study. Student participants were placed in six academic research laboratories located throughout the state. Student participants were interviewed three times during their ten-week internship and asked to record their personal reflections in electronic format. Participants from the established research community were also interviewed. These included both faculty mentors and other student laboratory personnel. Ongoing comparative analysis of the textual data revealed that laboratory organizational structure and social climate significantly influence acculturation outcomes for non-traditional URE participants. Student participants experienced a range of acculturation outcomes from full integration to marginalization. URE acculturation outcomes influenced development of non-traditional students? professional and academic self-concepts. Positive changes in students? self-concepts resulted in greater commitment to individual professional goals and academic aspirations. The findings from this study suggest that traditional science URE models can be successfully adapted to meet the unique needs of a non-traditional student population – community college students. These interpretations may encourage post-secondary educators, administrators, and policy makers to consider expanded access and support for non-traditional students seeking science URE opportunities.

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A three-level satellite to ground monitoring scheme for conservation easement monitoring has been implemented in which high-resolution imagery serves as an intermediate step for inspecting high priority sites. A digital vertical aerial camera system was developed to fulfill the need for an economical source of imagery for this intermediate step. A method for attaching the camera system to small aircraft was designed, and the camera system was calibrated and tested. To ensure that the images obtained were of suitable quality for use in Level 2 inspections, rectified imagery was required to provide positional accuracy of 5 meters or less to be comparable to current commercially available high-resolution satellite imagery. Focal length calibration was performed to discover the infinity focal length at two lens settings (24mm and 35mm) with a precision of O.1mm. Known focal length is required for creation of navigation points representing locations to be photographed (waypoints). Photographing an object of known size at distances on a test range allowed estimates of focal lengths of 25.lmm and 35.4mm for the 24mm and 35mm lens settings, respectively. Constants required for distortion removal procedures were obtained using analytical plumb-line calibration procedures for both lens settings, with mild distortion at the 24mm setting and virtually no distortion found at the 35mm setting. The system was designed to operate in a series of stages: mission planning, mission execution, and post-mission processing. During mission planning, waypoints were created using custom tools in geographic information system (GIs) software. During mission execution, the camera is connected to a laptop computer with a global positioning system (GPS) receiver attached. Customized mobile GIs software accepts position information from the GPS receiver, provides information for navigation, and automatically triggers the camera upon reaching the desired location. Post-mission processing (rectification) of imagery for removal of lens distortion effects, correction of imagery for horizontal displacement due to terrain variations (relief displacement), and relating the images to ground coordinates were performed with no more than a second-order polynomial warping function. Accuracy testing was performed to verify the positional accuracy capabilities of the system in an ideal-case scenario as well as a real-world case. Using many welldistributed and highly accurate control points on flat terrain, the rectified images yielded median positional accuracy of 0.3 meters. Imagery captured over commercial forestland with varying terrain in eastern Maine, rectified to digital orthophoto quadrangles, yielded median positional accuracies of 2.3 meters with accuracies of 3.1 meters or better in 75 percent of measurements made. These accuracies were well within performance requirements. The images from the digital camera system are of high quality, displaying significant detail at common flying heights. At common flying heights the ground resolution of the camera system ranges between 0.07 meters and 0.67 meters per pixel, satisfying the requirement that imagery be of comparable resolution to current highresolution satellite imagery. Due to the high resolution of the imagery, the positional accuracy attainable, and the convenience with which it is operated, the digital aerial camera system developed is a potentially cost-effective solution for use in the intermediate step of a satellite to ground conservation easement monitoring scheme.

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For over 3 centuries, diameter-limit harvesting has been a predominant logging method in the northeastern United States. Silvicultural theory asserts that such intensively selective harvesting can lead to genetic degradation. A decrease in softwood productivity has recently been reported in Maine - has a long history of dysgenic selection degraded the genetic resources of Maine softwoods, contributing to a decrease in growth and productivity? This study examines two aspects of potential implications of diameter-limit harvesting: effects on residual phenotypes of red spruce and impacts on genetic diversity of white pine. Radial growth of residual red spruce trees in stands experiencing 50 years of fixed diameter-limit harvesting was measured using annual increment rings and compared with residual red spruce trees in positive selection stands. Trees remaiaing after several rounds of diameter-limit harvesting exhibited sigdicantl y smaller radial sizes throughout their lives, and displayed significantly slower growth rates for the first 80 years of measured growth. These results strongly suggest that the largest and fastest-growing genotypes and their respective gene complexes determining good radial growth have been removed from the diameter-limit stand. Dysgenic selection can be observed in fixed diarneter-limit stands, resulting in a diminished genetic resource and decreased residual stand value. To examine more direct genetic implications of long-term diameter-limit harvesting, microsatellite DNA markers were implemented to study genetic diversity of eastern white pine in Maine. Three age groups of trees were studied: mature trees older than 200 years, juvenile trees 5-30 years old, and embryos. Trees were genotyped at 10 microsatellite loci. Overall genetic diversity levels of eastern white pine in Maine were extremely high, with an average observed heterozygosity of 0.762. Genetic differentiation was minimal among and between all three age groups, although an excess of heterozygotes was shown in the mature and juvenile groups that was not reflected in the embryo group, which actually had a slight heterozygote deficiency. Allele frequencies did not differ significantly between age groups, but did reveal more rare and low frequency alleles in the embryo groups than in the mature group. Overall, low frequency alleles comprise the largest portion of alleles in the sample population, with no common alleles evident overall. These results suggest that significant genetic degradation has either not occurred for white pine, or that the results of dysgenic selection have not yet emerged. It is clear, however, that selective harvesting could result in a loss of low frequency alleles, which are a primary reserve of evolutionary potential in a species. Implications of these studies affect industrial forestry, regional economics, and ecological concerns for the northeast. Long-term diameter-limit harvesting can lead to a degradation of residual phenotypes, and an overall decrease in stand quality. Potentially, a loss of low frequency, locally adapted alleles could result in a decrease of allelic richness and degradation of the regidnal genetic resource. Decreased genetic variation can lead to seriously limited evolutionary potential of species and ecosystems, particularly in rapidly changing environments. Based on these findings, I recommend a reassessment of any harvesting prescription that includes fixed diameter-limit removals, particularly for species that have low natural genetic diversity levels or a limited natural range, such as red spruce. Maintenance of a healthy genetic reserve can avoid effects of dysgenic harvesting.

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This is an investigation into the microbially mediated processes involved in the transformation of arsenic. With the recent change in the Federal Maximum Contaminant Level for arsenic in drinking water, an increasing amount of resources are being devoted to understanding the mechanisms involved in the movement of arsenic. Arsenic in drinking water typically comes from natural sources, but the triggers that result in increased release of arsenic from parent material are poorly understood. Knowledge of these processes is necessary in order to make sound engineering decisions regarding drinking water management practices. Recent years have brought forth the idea that bacteria play a significant role in arsenic cycling. Groundwater is a major source of potable water in this and many other countries. To date, no reports have been made indicating the presence and activity of arsenate reducing bacteria in groundwater settings, which may increase dissolved arsenic concentrations. This research was designed to address this question and has shown that these bacteria are present in Maine groundwater. Two Maine wells were sampled in order to culture resident bacteria that are capable of dissimilatory arsenate reduction. Samples were collected using anaerobic techniques fiom wells in Northport and Green Lake. These samples were amended with specific compounds to enrich the resident population of arsenate utilizing bacteria. These cultures were monitored over time to establish rates of arsenate reduction. Cultures fiom both sites exhibited arsenate reduction in initial enrichment cultures. Isolates obtained fiom the Green Lake enrichments, however, did not reduce arsenate. This indicates either that a symbiotic relationship was required for the observed arsenate reduction or that fast-growing fermentative organisms that could survive in high arsenate media were picked in the isolation procedure. The Northport cultures exhibited continued arsenate reduction after isolation and successive transfers into fiesh media. The cultured bacteria reduced the majority of 1 a arsenate solutions in less than one week, accompanied by a corresponding oxidation of lactate. The 16s rRNA fiom the isolate was arnplifled and sequenced. The results of the DNA sequence analysis indicate that the rRNA sequence of the bacteria isolated at the Northport site is unique. This means that this strain of bacteria has not been reported before. It is in the same taxonomic subgroup as two previously described arsenate respirers. The implications of this study are significant. The fact that resident bacteria are capable of reducing arsenate has implications for water management practices. Reduction of arsenate to arsenite increases the mobility of the compound, as well as the toxicity. An understanding of the activity of these types of organisms is necessary in order to understand the contribution they are making to arsenic concentrations in drinking water. The next step in this work would be to quantitj the actual loading of dissolved arsenic present in aquifers because of these organisms.

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This study was designed to investigate and describe the relationship among resilience, forgiveness and anger expression in adolescents. The purpose of the study was to explore whether certain adolescent resiliencies significantly related to positive or negative affective, behavioral, or cognitive levels of forgiveness and certain types of anger expression in adolescents. This study also investigated whether there were certain adolescent resiliencies and types of forgiveness that can predict lower levels of negative anger expression in adolescents. This research was built on two conceptual models: Wolin and Wolin's (1993) Challenge Model and the Forgiveness Process Model (Enright & Human Development Study Group, 1991). It was based on a quantitative, single-subject correlational research design. A multiple regression analysis was also used to explore possible effects of resilience and forgiveness on anger expression in adolescents. In addition, two demographic variables, Age and Gender, were examined for possible effects on anger expression. Data were gathered from a convenience sample sample of 70 students in three Maine public high schools using three separate assessment instruments: the Adolescent Resiliency Attitudes Scale (ARAS), the Adolescent Version of the Enright Forgiveness Inventory (EFI), and the Adolescent Anger Rating Scale (AARS). Correlational analyses were done on the scales and subscales of these surveys. Significant relationships were found between several adolescent resiliencies and forms of forgiveness as well as between some adolescent resiliencies and types of anger expression. The data indicated that Total Resiliency significantly correlated with Total Forgiveness as well as Total Anger. The findings also identified particular adolescent resiliencies that significantly predicted types of anger expression, while forgiveness did not predict types of anger expression. The data revealed that Age and Gender had no significant affect on anger expression. These findings suggest that the constructs of adolescent resilience and forgiveness have commonalities that can influence how adolescents express anger, and further suggest that intervention and prevention programs expand their focus to incorporate forgiveness skills. The findings from this study can provide critical information to counselors, therapists, and other helping professionals working with adolescents, on approaches to designing and implementing therapy modalities or developmental school guidance programs for adolescents.

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The Carrabassett Valley Sanitary District in Carrabassett Valley, Maine has utilized both a forest spray irrigation system and a Snowfluent™ system for the treatment of their wastewater effluent. This study was designed to evaluate potential changes in soil properties after approximately 20 years of treatment in the forested spray irrigation site and three years of treatment in the field Snowfluent™ site. In addition, grass yield and composition were evaluated on the field study sites. After treatment with effluent or Snowfluent™, soils showed an increase in soil exchangeable Ca, Mg, Na, and K, base saturation, and pH. While most constituents were higher in treated soils, available P was lower in treated soils compared to the controls. This difference was attributed to higher rates of P mineralization from soil organic matter due to an irrigation effect of the treatment, depleting available P pools despite the P addition with the treatment. Most of the differences due to treatment were greatest at the surface and diminished with depth. Depth patterns in soil properties mostly reflected the decreasing influence of organic matter and its decomposition products with depth as evidenced by significantly higher total C in the surface compared to lower horizons. There were decreasing concentrations of total N, and exchangeable or extractable Ca, Mg, Na, K, Mn, Zn, and P with depth. In addition, there was decreasing BS with depth, driven primarily by declining exchangeable Ca and Mg. Imgation with Snowfluent™ altered the chemical composition of the grass on the site. All element concentrations were significantly higher in the grass foliage except for Ca. The differences were attributed to the additional nutrients and moisture derived from the Snowfluent™. The use of forest spray imgation and Snowfluent™ as a wastewater treatment strategy appears to work well. The soil and vegetation were able to retain most of the applied nutrients, and do not appear to be moving toward saturation. Vegetation management may be a key tool for managing nutrient accumulation on the grass sites as the system ages.

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The present study sought to investigate the ways in which social anxiety impedes the development of romantic relationships across adolescence. Previous research has demonstrated a natural progression for romantic associations during adolescence in which teens transition from same- to mixed-sex peer groups, and finally to dyadic relationships with romantic partners (Connolly, Furman, Konarski, 2000; Dunphy, 1963). This model of development was the basis for the present investigation. Social anxiety was examined in terms of how it impacted affiliations at the same- and mixed sex peer group levels, and ultimately the formation of romantic relationships. This project involved administering a series of questionnaires and rating scales to students enrolled in the 9th through \2l grades. Participants included 457 adolescents (196 males, 261 females) recruited from public high schools in the state of Maine. The questionnaires assessed social anxiety, peer acceptance, heterosocial competence, gender composition of adolescent peer networks, dating history, and relationship quality with significant others in the adolescent's life. Higher levels of social anxiety were expected to be associated with impairment at each of these three levels. Given the proposed developmental progression, the effects of anxiety were theorized to be most pronounced within the older cohort of adolescents. Moreover, gender was expected to affect the pattern of results. Social anxiety is most prevalent among females (LaGreca, 1998; LaGreca & Lopez, 1998), who are also thought to progress along the proposed developmental trajectory more quickly than their male counterparts. Therefore, social anxiety was expected to impact the females to a greater degree at each of the three levels. Correlation coefficients, multivariate analyses of variance, and regression analyses were used to evaluate the data. Overall, despite some discrepant findings, the results supported the hypotheses. Social anxiety was affiliated with problems in the same-sex peer group, the mixed-sex clique, and, for older adolescents, romantic relationships. As expected, social anxiety affected females the most at each level. There seems to be a maladaptive pathway that socially anxious teens are following that is markedly different than their non-anxious counterparts.

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u.a. Angaben zur Farbenlehre Schopenhauers; Focher de Careil; Maine de Biran; Karl Gutzkow; Aufsatz zu Schopenhauer von Jues Frauenstädt;

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ouvrage posthume de Maine de Biran. Publ. par Cousin

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The United States health care system faces significant challenges, particularly with problems of the uninsured and with the rising costs of care. These problems lead many to study and discuss strategies for reforming the health care system. Four different plans for ideal health care reform, set forth by notable scholars or organizations, are explained herein. Then, states within the United States are examined in terms of their recent efforts at health care reform. Those states proposing significant changes to their health care systems are analyzed—namely, Maine, Massachusetts, and Vermont. The strategies used in these three states are compared to the strategies laid out by the experts in order to determine which strategies are the most popular in current health care reform efforts among the states studied here. These strategies are totaled to find which organization's plan for ideal reform seems to be the most popular. The strategies of managed competition are shown to be the most popular strategies among these three state health care reforms, while the strategies of the single-payer plan discussed herein were the least popular. All three states seem to utilize strategies that build upon their previous health care system, rather than implementing strategies that completely replace the previous system. ^

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Mr. John Murray, to whom the specimens of bottom deposits collected by the "Blake" were sent for examination, looked over the whole and selected some typical specimens. These have been described in detail, and he has added some general notes on the specimens characteristic, 1. of the Coast between the Gulf of Maine and Cape Hatteras; 2. of thee coast between Cape Hatteras and Lat. 31? 48' N.; 3. of the coasts around the greater and lesser Antilles ; and, finally, of the Gulf of Mexico and Straits of Florida.