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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Bringing broader impacts to the community via university K-12 partnerships: growth in and seed quality of Betula neoalaskana Sargent
Full text linkThesis (M.S.) University of Alaska Fairbanks, 2020Betula neoalaskana Sargent is the most abundant birch species in Alaska. All parts of the tree can be used in creating timber and non-timber products, and birch stands provide high-value ecosystem services for ecotourism and outdoor recreational purposes. For these reasons, the OneTree Alaska program of the University of Alaska Fairbanks uses Interior Alaska white birch as the centerpiece of its work. This M.S. thesis is a contribution to OneTree Alaska's goal of raising the public's understanding of the effects of Interior Alaska's lengthening growing season on the growth and reproduction of the local birch resource. Specifically, the thesis relates to the growth and reproduction of the offspring of the original "one trees" harvested on Nenana Ridge in October 2009. The saplings have been growing in the Generation OneTree Research Plot in the T-field, north of the Smith Lake on the University of Alaska Fairbanks campus, since June 2011 and represent half-sibling families reared from the seed of 8 maternal trees. As seedlings, they were reared for growing seasons of variable length, both by students at the Watershed Charter School of the Fairbanks North Star Borough and by OneTree personnel in a University of Alaska Fairbanks growth chamber. Prior to this study, end of year measurements had been taken of the young trees in the T-field for all but one year and established that the length of the first growing season persistently affected the number of stems and the diameter at breast height (DBH) of the main stems. New findings in this thesis show that the elevation difference among trees impacts the number of infructescences and germination rates but not the number of male catkins. At least for the 2018 seed crop, seeds from trees planted at higher elevations in the T-field showed higher germination rates than those planted at lower elevations, while they produce fewer infructescences at up slope. Other findings demonstrate that sibling family does not have an effect on either vegetative or reproductive growth. Instead, the length of the first growing season provides for a diversity of canopy shapes across sibling families. The most significant finding is the effect of elevation on female reproductive growth: It suggests a number of next steps, tools, and analysis to better understand environmental variables that work alongside elevation in determining growth and reproductive success. Soil moisture and pH (H2O), Carbon/Nitrogen ratio, Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to determine micronutrient composition, sensors to capture wind speed/direction and solar radiation, photosynthetic traits, and chlorophyll concentration measurements could all be valuable in further elucidating the hypotheses being advanced by this research regarding the interactions between changing environment and reproduction.Heiwa Nakajima FoundationChapter 1: Introduction -- 1.1. Betula neoalaskana Sargent: boreal forest and birch in Alaska -- 1.2. OneTree Alaska -- 1.2.1. Broader Impacts Activity -- 1.2.2. STEM to STEAM -- 1.2.3. Concept and History -- 1.3. Justification. Chapter 2. T-field Vegetative and Reproductive growth -- 2.1. Introduction -- 2.1.1. Problem statements -- 2.1.2. Hypothesis -- 2.2. Material, Methods and Timeline of T-field -- 2.2.1. Original experiment from 2009 to 2011 -- 2.2.2. LiDAR data and GIS Analysis for T-field in 2018 -- 2.2.3. Growing condition: precipitation and temperature data -- 2.2.4. Stem numbers, Height, and DBH measurement in 2018 by a class -- 2.2.5. Reproduction assessment -- 2.2.6. Statistic analysis -- 2.3. Results -- 2.3.1. Vegetative data of T-field in 2018 -- 2.3.2. Reproductive growth data of T-field in 2018 -- 2.4. Discussion -- 2.4.1. The effect of the first growing seasons -- 2.4.2. The effect of elevation and the distance from the edge of the sub-canopy -- 2.4.3. Resemblance from the former studies on birch and critiques. Chapter 3. Germination Experiment -- 3.1 Introduction -- 3.1.1. Problem statement -- 3.1.2. Hypothesis -- 3.2 Material, Methods, and Timeline -- 3.2.1. Seed sampling from T-field in 2018 -- 3.2.2. Cupcake method -- 3.2.3. Growing conditions in the greenhouse -- 3.2.4. Statistic analysis -- 3.3. Qualification of the cupcake method -- 3.3.1. Result of the statistic analysis -- 3.3.2. Price of the cupcake method -- 3.3.3. Recommendation -- 3.4. Germination results -- 3.4.1. The increment of germination over 21 days -- 3.4.2. The numbers of germination on 21st day -- 3.5. Discussion -- 3.5.1. Reproductive ecology in life strategy and seed vigor -- 3.5.2. Resemblance from the former studies and questions for the future. Chapter 4. General Discussion and Conclusion -- 4.1. General discussion -- 4.2. General conclusion -- 4.3. Further research suggestions -- 4.4. Germination experiment protocol for citizen scientists -- 4.4.1. Introductory remarks -- 4.4.2. Find Birch -- 4.4.3. Find and get birch seeds -- 4.4.4. Prepare tray and soil -- 4.4.5. Sow seeds -- 4.4.6. Take care of seeds -- 4.4.7. Find germination -- 4.5. Afterthoughts -- Literature cited
Efficient alternative food systems for earth and space
Full text linkThesis (M.S.) University of Alaska Fairbanks, 2020Alternative foods are a source of human-edible calories derived from an unconventional source or process. This thesis includes two alternative foods: (i) crops grown under low-tech greenhouses in low sunlight environments and (ii) hydrogen-oxidizing bacteria (HOB) in space and Earth refuges, such as to repopulate the Earth. The purpose of alternative foods is to ensure food security for human survival. During a global catastrophic risk (GCR) scenario, such as nuclear winter or super volcanic eruption, the sun may be obscured, causing lack of crop production and therefore global food shortages. The purpose of this thesis was to improve the cost and energy use of producing food during a GCR by avoiding the need to use artificial light photosynthesis. As a solution, a low-tech greenhouse scaling method was designed that could feed the Earth as quickly and cost-effectively as possible during a GCR, such as nuclear winter. Using concepts derived for scaling HOB single cell protein (SCP), a cost analysis was conducted for space that relates to Earth refuges. The cost of HOB was compared to that of microalgae SCP and of dry prepackaged food in a closed-loop system. Low-tech greenhouses were designed with basic materials to continue the production of non-cold tolerant crops at low cost; cold tolerant crops would be able to grow outside of greenhouses where it does not freeze. Scaling of low-tech greenhouses, which would add a cost to food of $2.30 /kg dry, is currently one of the most effective alternative foods for Earth. HOB is an effective method of converting electrical energy into food, having an electricity to biomass energy conversion efficiency of 18% versus 4.0% for artificial light (vertical farming) of microalgae (other crops would be even less efficient).Alaska Space Grant ProgramChapter 1: General introduction -- Chapter 2: Scaling of greenhouse crop production in low sunlight environments -- Abstract -- 2.1. Introduction -- 2.2. Methods -- 2.2.1. Greenhouse design -- 2.2.2. Global market for components -- 2.2.3. Crop resiliency and global crop demand -- 2.3. Solution -- 2.3.1. Scaling approach -- 2.3.2. Economic analysis -- 2.4. Discussion -- 2.5. Conclusions -- 2.6 References. Chapter 3: Food in space from hydrogen oxidizing bacteria -- Abstract -- 3.1. Introduction -- 3.2 Methods -- 3.2.1. Calculation of equivalent system mass -- 3.2.2. Design of alternatives -- 3.2.3. Microbial energy efficiencies -- 3.2.4. Power generation methods -- 3.3. Results -- 3.4. Discussion -- 3.4.1. Life support considerations -- 3.4.2. Equivalent system mass contributions -- 3.4.3. Alternatives comparison -- 3.5. Conclusions -- 3.6. References. Chapter 4: General Conclusions
Preliminary Fairbanks Bee Pollinator Protection Plan
Full text linkMaster's Project (M.S.) University of Alaska Fairbanks, 2020Global declines in pollinator species have been documented in several studies across the United States, Canada, and Europe. Honeybees, bumble bees and Monarch butterflies have been hit particularly hard in the US. This Preliminary Fairbanks Bee Pollinator Protection Plan recommends ways to increase public awareness of the problems facing bees and other pollinators, methods to increase and protect pollinator habitat and steps to take to reduce the use of pesticides. The plan also includes a list of native and nonnative plants that grow well in the Fairbanks area and that are attractive to insect pollinators. Planting these species can greatly increase the local habitat for pollinators.
In developing the plan, I evaluated 12 pollinator plans from other areas, learned about local pollinators and their habitat requirements, and surveyed local beekeepers. To create the goals, objectives and actions included in this plan, I combined ideas from each of these three sources plus ideas of my own.
The plan is not intended to be implemented by any one individual or agency. Instead, the plan can be used by anyone interested in improving pollinator habitat. If you have a backyard, access to a community garden, or just a few pots or a windowsill, you can create pollinator habitat. In addition to individuals, there are many businesses, government agencies, non-profits and other organizations that may be interested in taking steps listed in the plan to benefit bees and other pollinators
Crop modeling to assess the impact of climate change on spring wheat growth in sub-Arctic Alaska
Full text linkThesis (M.S.) University of Alaska Fairbanks, 2019In the sub-arctic region of Interior Alaska, warmer temperatures and a longer growing season caused by climate change could make spring wheat (Triticum aestivum L.) a more viable crop. In this study, a crop model was utilized to simulate the growth of spring wheat in future climate change scenarios RCP4.5 (medium-low emission) and RCP8.5 (high emission) of Fairbanks, Alaska. In order to fulfill such simulation, in 2018 high quality crop growth datasets were collected at the Fairbanks and Matanuska Valley Experiment Farms and along with historic variety trial data, the crop model was calibrated and validated for simulating days to maturity (emergence to physiological maturity) and yield of spring wheat in Fairbanks. In the Fairbanks 1989-2018 (baseline) climate, growing season (planting to physiological maturity) average temperature and total precipitation are 15.6° C and 122 mm, respectively. In RCP4.5 2020-2049 (2035s), 2050-2079 (2065s), and 2080-2099 (2090s) projected growing season average temperature and total precipitation are 16.7° C, 17.4° C, 17.8° C and 120 mm, 112 mm, 112 mm, respectively. In RCP8.5 2035s, 2065s, and 2090s projected growing season average temperature and total precipitation are 16.8° C, 18.5° C, 19.5° C and 120 mm, 113 mm, 117 mm, respectively. Using Ingal, an Alaskan spring wheat, the model simulated days to maturity and yield in baseline and projected climate scenarios of Fairbanks, Alaska. Baseline days to maturity were 69 and yield was 1991 kg ha-1. In RCP4.5 2035s, 2065s, and 2090s days to maturity decreased to 64, 62, 60 days, respectively, and yield decreased 2%, 6%, 8%, respectively. In RCP8.5 2035s, 2065s, and 2090s days to maturity decreased to 64, 58, 55 days, respectively, and yield decreased 1%, 3%, then increased 1%, respectively. Adaptation by cultivar modification to have a growing degree day requirement of 68 days to maturity in RCP4.5 2035s and RCP8.5 2035s resulted in increased yields of 4% and 5%, respectively. Climatic parameters of temperature and precipitation per growing season day are projected to become more favorable to the growth of spring wheat. However, precipitation deficit, an indicator of water stress was found to stay similar to the baseline climate. Without adaption, days to maturity and yield are projected to decrease. Selection and/or breeding of spring wheat varieties to maintain baseline days to maturity are a priority to materialize yield increases in the area of Fairbanks, Alaska.University of Alaska Fairbanks Paul D. Coverdell Fellows Program for returned Peace Corps Volunteers, USDA Hatch GrantChapter 1: Spring wheat crop modeling to project future growth in Alaska -- Chapter 2: Calibration and validation of CERES-Wheat in sub-arctic Alaska -- Chapter 3: Projections of spring wheat growth in Alaska: Opportunities and adaptions in a changing climate -- Chapter 4: Synthesis -- Appendix A: Data collection for crop model use
High tunnel production of lettuce (Lactuca sativa) and snap beans (Phaseolus vulgaris l.) in a High Latitude location
Full text linkThesis (M.S.) University of Alaska Fairbanks, 2006.Fairbanks, Alaska (lat. 64°49’N) has a short, variable growing season which necessitates alternative growing techniques for reliable vegetable production. Air and soil temperatures, relative humidity, light penetration, and management requirements were evaluated for a double bay high tunnel [15.8 m wide × 3.7 m high × 14.6 m long]. Mean air temperature was 0.5 °C and soil 1.2 °C higher in the high tunnel than the adjacent field, but differences varied with ventilation and heating practices. Yield and growth characteristics of lettuce (Lactuca sativa: ‘Paris Island cos’ and ‘Two Star’) and snap beans (Phaseolus vulgaris L.: ‘Concesa’ and ‘Provider’) were evaluated. Lettuce was frost hardy in the open field, prone to bolting in the high tunnel, and in general did not benefit from the high tunnel environment, except in quality due to cleanliness. ‘Concesa’ produced significantly more in the high tunnel compared with the field (P < 0.005). ‘Provider’, produced more in the high tunnel in 2006 compared to the field, but differences were not statistically significant over two seasons. The perceived benefits of high tunnel production included protection from frost, wind, pest, and rain, improved yields depending on crop and cultivar, and decreased weed emergence and moisture accumulation.Signature Page -- Title Page : Abstract -- Table of Contents -- List of Figures -- List of Tables -- List of Appendices : Page -- Acknowledgements -- Chapter 1 General Introduction : Summary ; High Tunnels ; Lettuce (Lactuca sativa) ; Snap beans (Phaseolus vulgaris L.) ; Literature Cited -- Chapter 2 Northern Field Production of Leaf and Romaine Lettuce using a High Tunnel : Summary ; Introduction ; Materials and Methods ; Results and Discussion ; Literature Cited -- Chapter 3 High Tunnels Improved Snap Bean Production in Alaska : Summary ; Introduction ; Materials and Methods ; Results and Discussion ; Literature Cited -- Chapter 4 General Conclusion : Summary ; High Tunnel Use and Research in the United States ; High Tunnel Production of Warm Season Crops ; High Tunnel Management ; Soil Fertility ; High Tunnel Advantages over Low Tunnels ; High Tunnel Operating Costs ; Concluding Remarks ; Literature Cite
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Apple production potential in Interior Alaska within a state of amplified climatic change
Full text linkMaster's Project (M.N.R.E.) University of Alaska Fairbanks, 2021Successful apple (Malus Domestica) tree and fruit growing have been ongoing in Alaska
for over 100 years. At the outset, crabapples were the only varieties produced, but as
agriculturalists, orchardists, and farmers began to experiment with grafting coldhardy rootstock with scions, new cultivars began to emerge, with varying degrees of
success, throughout the state. In addition to experimental cultivars, the climate began
to change, with an overall warming trend emerging. Together these variables could be
the winning combination to large-scale apple orchards being started in the state of
Alaska. More fruit production in the state would strengthen both the small
agricultural industry and the state’s food security posture. If raw fruit products can be
produced, then possibly other related business and commerce will become possible,
such as production of apple cider, apple sauce, fruit leather, and preserves.
The state of Washington, particularly the Eastern side, has prime apple-growing
weather and climate. Of all the states, Washington produces the most apples
annually. The national top ten most consumed apples are grown there. The Eastern
Washington climatic region was chosen for comparison and a point of reference versus
the projected interior Alaska region climate. Long-season, later-harvest apples are
grown in Eastern Washington, but not in Alaska. This type of apple is valuable and
desirable due to its potential for stable, long-term storage. Currently, Alaska-grown
apples can be of high quality but are smaller to medium-sized, in general, and not
conducive to long-term storage. Long-term storage compatible apples are desirable
because that trait makes year-round apple eating possible.
The purpose of this research project is to evaluate whether longer growing
seasons, due to climate change, will potentially allow production, in interior Alaska, of
late season apples. The analysis approach includes a combination of personal
observations, literature review, climatic modeling, evaluation, and synthesis of data
from multiple sources.
Climatic trends and data from both past and future years were examined.
Environmental variables such as atmospheric temperatures, precipitation, first and
last frost dates, plant hardiness zones, and growing degree days were included in the
analysis. It was found that within the next two to three decades, or sooner, with some
model predictions, that the interior Alaska climate will be approaching that of Eastern
Washington, although still cooler in both the winter and summer. Nevertheless, hardiness zone compatibility indicates that interior Alaska will have a climate that is
conducive to growing both the shorter season apples (generally used for cider) and
later-harvest, long-term storage apple varieties (mainly used for direct consumption).
Interior Alaska average annual air temperatures have been slowly but steadily
climbing over time, with increases evident year-round. Precipitation has also been
found to be increasing, with rain in some locations during the winter (where previously
there was no rainfall) melting the snow and affecting the snow coverage of an area.
Rainfall has been increasing in the shoulder seasons too, affecting the growing season.
Evapotranspiration has also been projected to increase, potentially nullifying the
benefit of increased precipitation for natural crop irrigation purposes. With permafrost
also degrading statewide, soil conditions may naturally get drier. Irrigation and on-farm water storage may prove to be a short-term method to overcome more arid environmental conditions
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