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2012

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Full-Text Articles in Social and Behavioral Sciences

Nevada Interagency Volunteer Program: Helping Hands Across Public Lands—Phase Ii: Final Project Report, December 31, 2012, Margaret N. Rees Dec 2012

Nevada Interagency Volunteer Program: Helping Hands Across Public Lands—Phase Ii: Final Project Report, December 31, 2012, Margaret N. Rees

Get Outdoors Nevada

  • Maintained a central clearinghouse created for Southern Nevada public lands volunteers, including: ─ an online volunteer data-management application (Volgistics) adopted and customized for the program and populated with 8,500 active and 961 mailing list volunteer records ─ a community outreach Web site that currently averages 8,230 pages viewed per month since July 2007 and has aided in the recruitment of 11,943 volunteers ─ updated website to word press for sustainability ─ branding development and marketing and outreach tool creation
  • Updated Standard Operating Procedures (SOPs) for all areas of Interagency Volunteer Program Management—recruitment, training, recognition, retention of volunteers, event planning, and ...


Sndo Hector's Helpers Youth Engaging The Community Through Social Media: Annual Progress Report, Period Covering June 1, 2012 - December 31, 2012, Margaret N. Rees Dec 2012

Sndo Hector's Helpers Youth Engaging The Community Through Social Media: Annual Progress Report, Period Covering June 1, 2012 - December 31, 2012, Margaret N. Rees

Anti-littering Programs

The Hector’s Helpers Youth Engaging the Community through Social Media project was designed to develop civic and environmental stewardship skills as students receive training in administering social media accounts (e.g., Facebook, twitter, Youtube). The project is an extension of the Hector’s Helpers program developed through a cooperative agreement and run under the branding of Don’t Trash Nevada. Participants in the project are known as the Social Media Squad (SMS). The following activities were completed:

  • Supervision of youth completing the pilot program initiated in an earlier cooperative agreement
  • Recruitment of youth to apply for the Social Media ...


Observatory Of Trends In Software Related Microblogs, Achananuparp Palakorn, Nelman Lubis Ibrahim, Yuan Tian, David Lo, Ee Peng Lim Dec 2012

Observatory Of Trends In Software Related Microblogs, Achananuparp Palakorn, Nelman Lubis Ibrahim, Yuan Tian, David Lo, Ee Peng Lim

David LO

Microblogging has recently become a popular means to disseminate information among millions of people. Interestingly, software developers also use microblog to communicate with one another. Different from traditional media, microblog users tend to focus on recency and informality of content. Many tweet contents are relatively more personal and Opinionated, compared to that of traditional news report. Thus, by analyzing microblogs, one could get the up-to-date information about what people are interested in or feel toward a particular topic. In this paper, we describe our microblog observatory that aggregates more than 70,000 Twitter feeds, captures software-related tweets, and computes trends ...


Automatic Classification Of Software Related Microblogs, Philips Kokoh Prasetyo, David Lo, Achananuparp Palakorn, Yuan Tian, Ee Peng Lim Dec 2012

Automatic Classification Of Software Related Microblogs, Philips Kokoh Prasetyo, David Lo, Achananuparp Palakorn, Yuan Tian, Ee Peng Lim

David LO

Millions of people, including those in the software engineering communities have turned to microblogging services, such as Twitter, as a means to quickly disseminate information. A number of past studies by Treude et al., Storey, and Yuan et al. have shown that a wealth of interesting information is stored in these microblogs. However, microblogs also contain a large amount of noisy content that are less relevant to software developers in engineering software systems. In this work, we perform a preliminary study to investigate the feasibility of automatic classification of microblogs into two categories: relevant and irrelevant to engineering software systems ...


Ict For Poverty Alleviation In Pacific Island Nations: Study Of Icts4d In Fiji, Deogratias Harorimana, Opeti Rokotuinivono, Emali Sewale, Fane Salaiwai, Marica Naulu, Evangelin Roy Dec 2012

Ict For Poverty Alleviation In Pacific Island Nations: Study Of Icts4d In Fiji, Deogratias Harorimana, Opeti Rokotuinivono, Emali Sewale, Fane Salaiwai, Marica Naulu, Evangelin Roy

Dr Deogratias Harorimana

ICT for Poverty Alleviation in Pacific Island Nations: Study of ICTs4D in Fiji There has been a vague and little knowledge on the role or potential of Information and Communications Technologies (ICTs) in relation to addressing poverty in Fiji. This may be probably due to the newness of the technology in the South Pacific Region as a whole but also probably due to the fact that only 9.7% of the current Fiji 931,000 populations are internet users (ITC Figures 2011). This paper reports on finding how ICTs is contributing towards poverty alleviation in Fiji. On the basis of ...


Combining Mbr And Nf/Ro Membrane Filtration For The Removal Of Trace Organics In Indirect Potable Water Reuse Applications, William Price, Nichanan Tadkaew, Long Nghiem, Stuart Khan, Abdulhakeem Alturki, James Mcdonald Dec 2012

Combining Mbr And Nf/Ro Membrane Filtration For The Removal Of Trace Organics In Indirect Potable Water Reuse Applications, William Price, Nichanan Tadkaew, Long Nghiem, Stuart Khan, Abdulhakeem Alturki, James Mcdonald

Long D Nghiem

The aim of this study was to demonstrate the complementarities of combining membrane bioreactor (MBR) treatment with nanofiltration (NF) or reverse osmosis (RO) membrane filtration for the removal of trace organic contaminants for potential indirect potable water recycling applications. Four commercially available NF/RO membranes, namely NF270, NF90, BW30 and ESPA2, were selected for this investigation. Challenge tests were conducted with 40 trace organic compounds at concentrations of approximately 2 ng/L in initial wastewater solutions using a laboratory scaleMBRsystem and a cross-flow NF/RO rig. The results suggest that the MBR system effectively removes hydrophobic and biodegradable trace organic ...


An Assessment Of The Effects Of Desertification In Yobe State, Nigeria, Jibril Musa Phd Dec 2012

An Assessment Of The Effects Of Desertification In Yobe State, Nigeria, Jibril Musa Phd

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

Desertification is one of the most serious environmental and socio-economic problems of our time. Desertification describes circumstances of land degradation in arid, semi-arid and dry sub-humid regions resulting from the climatic variation and human activities. The fundamental goal of this thesis was to assess the effects of desertification in Yobe State, Nigeria. The present threat of desertification in the sahel has reached an alarming stage where crops cultivation and animal rearing/grazing are no more productive, soil has lost its nutrient/fertility, various infrastructure had given way because of windstorm from the neighbouring Niger Republic and sand dunes had taken ...


Tutorial Report: Understanding Spatial Thought Through Language Use, Thora Tenbrink, Tommaso D'Odorico, Christoph Hertzberg, Güzin Mazman, Chiara Meneghetti, Nina Reshöft, Jinlong Yang Dec 2012

Tutorial Report: Understanding Spatial Thought Through Language Use, Thora Tenbrink, Tommaso D'Odorico, Christoph Hertzberg, Güzin Mazman, Chiara Meneghetti, Nina Reshöft, Jinlong Yang

Journal of Spatial Information Science

The tutorial "Understanding spatial thought through language use" took place at the International Spatial Cognition Conference on August 31, 2012 at Kloster Seeon in Germany. This report outlines the main rationale for the tutorial along with central contributions by its participants, who considerably enhanced the success of the tutorial by sharing and discussing their own research experiences with respect to the analysis of language in spatial cognition contexts. The tutorial's website is http://knirb.net/TutorialSC2012.html.


The Influence Of Landscape Variation On Landform Categorization, Maia Williams, Werner Kuhn, Marco Painho Dec 2012

The Influence Of Landscape Variation On Landform Categorization, Maia Williams, Werner Kuhn, Marco Painho

Journal of Spatial Information Science

This paper compares the landform vocabularies of residents from two regions in Portugal. Participants described both their own and the other less familiar landscapes in response to video footage of the regions. The results indicate that participants used more detailed vocabularies to describe the known landscape compared to the less familiar study site with detail triggered by individual place recognition. A relationship between landform lexica content and landscape type was observed in the relative placement of detail within each vocabulary. The observed drivers of categorization were the salient features of the landscape (elevation and land cover) and utilitarian motivations (land ...


Geospatial Images In The Acquisition Of Spatial Knowledge For Wayfinding, Pyry Kettunen, Katja Irvankoski, Christina M. Krause, Tapani Sarjakoski, L. Tiina Sarjakoski Dec 2012

Geospatial Images In The Acquisition Of Spatial Knowledge For Wayfinding, Pyry Kettunen, Katja Irvankoski, Christina M. Krause, Tapani Sarjakoski, L. Tiina Sarjakoski

Journal of Spatial Information Science

Geospatial images such as maps and aerial photographs are important sources of spatial knowledge that people use for wayfinding. The rapid development of geodata acquisition and digital graphics has recently led to rather complete geographic coverage of both traditional and novel types of geospatial images. Divergent types of geospatial images vary in their support of human acquisition of spatial knowledge. However evaluative studies about the acquisition of spatial knowledge from the diversity of geospatial images have been rare. In this article we review a variety of literature about the acquisition of spatial knowledge while paying particular attention to the role ...


Approaching The Notion Of Place By Contrast, Stephan Winter, Christian Freksa Dec 2012

Approaching The Notion Of Place By Contrast, Stephan Winter, Christian Freksa

Journal of Spatial Information Science

Place is an elusive notion in geographic information science. This paper presents an approach to capture the notion of place by contrast. This approach is developed from cognitive concepts and the language that is used to describe places. It is complementary to those of coordinate-based systems that dominate contemporary geographic information systems. Accordingly the approach is aimed at explaining structures in verbal place descriptions and at localizing objects without committing to geometrically specified positions in space. We will demonstrate how locations can be identified by place names that are not crisply defined in terms of geometric regions. Capturing the human ...


Spatial Reasoning With Augmented Points: Extending Cardinal Directions With Local Distances, Reinhard Moratz, Jan Oliver Wallgrün Dec 2012

Spatial Reasoning With Augmented Points: Extending Cardinal Directions With Local Distances, Reinhard Moratz, Jan Oliver Wallgrün

Journal of Spatial Information Science

We present an approach for supplying existing qualitative direction calculi with a distance component to support fully fledged positional reasoning. The general underlying idea of augmenting points with local reference properties has already been applied in the OPRAm calculus. In this existing calculus point objects are attached with a local reference direction to obtain oriented points and able to express relative direction using binary relations. We show how this approach can be extended to attach a granular distance concept to direction calculi such as the cardinal direction calculus or adjustable granularity calculi such as OPRAm or the Star calculus. We ...


Socio-Environmental Considerations At The Usuma Reservoir In Abuja, Nigeria, Fanan Ujoh Mr, James Ikyernum Mr, Olarewaju O. Ifatimehin Dr Dec 2012

Socio-Environmental Considerations At The Usuma Reservoir In Abuja, Nigeria, Fanan Ujoh Mr, James Ikyernum Mr, Olarewaju O. Ifatimehin Dr

Dr. Fanan Ujoh

Reservoirs are Man’s attempt towards water re-distribution from regions/seasons of abundance/surplus to regions/seasons of scarcity. This study focuses on socio-environmental impacts of the Lower Usuma dam in Abuja, on its four surrounding communities. Stratified random sampling technique was employed in the administration of a questionnaire to 200 respondents. Using descriptive statistics and the student t-test for the analysis, the study discovered that: (i) there has been no significant improvement in infrastructure provision by Government; (ii) cases of water-borne diseases are high; (iii) the communities have lost land for cultivation; and, (iv) the communities believe that the ...


Using Remote Sensing Data To Improve Rice Production In Kutigi, Niger State, Nigeria, Jibril Musa Phd, M B. Yunusa Dec 2012

Using Remote Sensing Data To Improve Rice Production In Kutigi, Niger State, Nigeria, Jibril Musa Phd, M B. Yunusa

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

This research work looked in the used of Remote Sensing to improve Agricultural production in Kutigi, Niger State. The aim of the study is to use remote sensing to improve rice farming activities in Kutigi, Niger State. It is very important to identify such methods to improve Agricultural production because experts are always interested in new researches and findings to better the standard of living in any environment. In view of this, Remotely-sensed data could be used or employed to elevate most of these agricultural problems in Kutigi through the following objectives: Using Landsat imagery to assess the present landuse ...


Simulations In 3d Tactics, Interdiction And Multi-Agent Modelling, A. R. Green, I. C. Piper, Daniel Keep, C. J. Flaherty Dec 2012

Simulations In 3d Tactics, Interdiction And Multi-Agent Modelling, A. R. Green, I. C. Piper, Daniel Keep, C. J. Flaherty

Dr Ian Piper

The analysis of vulnerabilities in large complex spaces is fundamentally problematic. The lack of capacity to generate a threat assessment merely exacerbates this problem. Lacking as well, in current literature is a developed methodology. To overcome this problem, we propose an approach using multi-agent modelling, which is also melded with three dimensional (3D) tactical understandings. Our approach builds on a microsimulation decision support tool, which was developed for a behavioural simulation of CBRN events. Microsimulation is based on the individual; who as an individual has a number of attributes, and which are stochastic (when repeated within an attribute). This approach ...


Nursing Females Are More Prone To Heat Stress: Demography Matters When Managing Flying-Foxes For Climate Change, Stephanie T. Snoyman, Jasmina Munich, Culum Brown Dec 2012

Nursing Females Are More Prone To Heat Stress: Demography Matters When Managing Flying-Foxes For Climate Change, Stephanie T. Snoyman, Jasmina Munich, Culum Brown

Ecological Impacts of Climate Change

Determining the underlying mechanisms responsible for species-specific responses to climate change is important from a species management perspective. The grey-headed flying-fox, Pteropus poliocephalus, is listed as vulnerable but it also a significant pest species for orchardists and thereby presents an interesting management conundrum. Over the last century, the abundance of the grey-headed flying-fox, P. poliocephalus, in Australia has decreased due to a variety of threatening processes but has increased in abundance in urban areas. These flying-foxes are highly susceptible to extreme heat events which are predicted to increase in the future under climate change scenarios. Exceptionally hot days result in ...


Time Series, Unit Roots, And Cointegration: An Introduction, Lonnie K. Stevans Dec 2012

Time Series, Unit Roots, And Cointegration: An Introduction, Lonnie K. Stevans

Lonnie K. Stevans

The econometric literature on unit roots took off after the publication of the paper by Nelson and Plosser (1982) that argued that most macroeconomic series have unit roots and that this is important for the analysis of macroeconomic policy. Yule (1926) suggested that regressions based on trending time series data can be spurious. This problem of spurious correlation was further pursued by Granger and Newbold (1974) and this also led to the development of the concept of cointegration (lack of cointegration implies spurious regression). The pathbreaking paper by Granger (1981), first presented at a conference at the University of Florida ...


An Estate Dilemma - Inaccessible Assets Hiding Behind Passwords And Encryption, Douglas J. Henderson Dec 2012

An Estate Dilemma - Inaccessible Assets Hiding Behind Passwords And Encryption, Douglas J. Henderson

DOUGLAS J HENDERSON

Every person living in the modern world holds valuable assets, data, or information in digital mediums. Digital mediums include not only digital hardware storage mediums in personal possession (like external hard drives and internal hard drives within laptop and desktop computers, personal digital assistants, cell phones, and the like), but also those only accessible through a network. Because so much is held in digital mediums, when an individual dies or becomes incapacitated, another person must know how to access the incapacitated person’s digital assets and other important information (this person is known herein as the ‘Responsible Party’). There are ...


Data Curation Is For Everyone! The Case For Master's And Baccalaureate Institutional Engagement With Data Curation, Yasmeen Shorish Dec 2012

Data Curation Is For Everyone! The Case For Master's And Baccalaureate Institutional Engagement With Data Curation, Yasmeen Shorish

Yasmeen Shorish

This article describes the fundamental challenges to data curation, how these challenges may be compounded for smaller institutions, and how data management is an essential and manageable component of data curation. Data curation is often discussed within the confines of large, research universities. As a result, master’s and baccalaureate institutions may be left with the impression that they cannot engage with data curation. However, by proactively engaging with faculty, libraries of all sizes can build closer relationships and help educate faculty on data documentation and organization best practices. Experiences from one master’s comprehensive institution as it engages with ...


Predicting Avian Distributions To Evaluate Spatiotemporal Overlap With Locust Control Operations In Eastern Australia, Judit K. Szabo, Pamela J. Davy, Michael Hooper, Lee Astheimer Dec 2012

Predicting Avian Distributions To Evaluate Spatiotemporal Overlap With Locust Control Operations In Eastern Australia, Judit K. Szabo, Pamela J. Davy, Michael Hooper, Lee Astheimer

Dr Pamela Davy

Locusts and grasshoppers cause considerable economic damage to agriculture worldwide. The Australian Plague Locust Commission uses multiple pesticides to control locusts in eastern Australia. Avian exposure to agricultural pesticides is of conservation concern, especially in the case of rare and threatened species. The aim of this study was to evaluate the probability of pesticide exposure of native avian species during operational locust control based on knowledge of species occurrence in areas and times of application. Using presence-absence data provided by the Birds Australia Atlas for 1998 to 2002, we developed a series of generalized linear models to predict avian occurrences ...


A New Phase Unwrapping Algorithm Based On Three Wavelength Phase Shift Profilometry Method, Limei Song, Xiaoxiao Dong, Jiangtao Xi, Yanguang Yu, Chaokui Yang Dec 2012

A New Phase Unwrapping Algorithm Based On Three Wavelength Phase Shift Profilometry Method, Limei Song, Xiaoxiao Dong, Jiangtao Xi, Yanguang Yu, Chaokui Yang

Dr Yanguang Yu

Phase Shift Profilometry (PSP) method is widely used in 3D shape measurement. The advantage of the PSP method is that it is less sensitive to the surface reflectivity variations and the object can be measured point by point. But if only a single wavelength λ1 is used, the step height cannot be larger than λ1/4. In order to measure step height object, Gray Code (GC) and Multi-Wavelength Phase Shift Profilometry (MWPSP) method are used. But the GC method cannot solve the problem of the objects with a variety of colors under different illumination. The shortcoming of MWPSP ...


Kernel Density Estimation Of Traffic Accidents In A Network Space, Zhixiao Xie, Jun Yan Dec 2012

Kernel Density Estimation Of Traffic Accidents In A Network Space, Zhixiao Xie, Jun Yan

Dr Jun Yan

A standard planar Kernel Density Estimation (KDE) aims to produce a smooth density surface of spatial point events over a 2-D geographic space. However, the planar KDE may not be suited for characterizing certain point events, such as traffic accidents, which usually occur inside a 1-D linear space, the roadway network. This paper presents a novel network KDE approach to estimating the density of such spatial point events. One key feature of the new approach is that the network space is represented with basic linear units of equal network length, termed lixel (linear pixel), and related network topology. The use ...


Becoming Differently Modern: Geographic Contributions To A Generative Climate Politics, Lesley M. Head, Christopher R. Gibson Dec 2012

Becoming Differently Modern: Geographic Contributions To A Generative Climate Politics, Lesley M. Head, Christopher R. Gibson

Chris Gibson

Anthropogenic climate change is a quintessentially modern problem in its historical origins and discursive framing, but how well does modernist thinking provide us with the tools to solve the problems it created? On one hand even though anthropogenic climate change is argued to be a problem of human origins, solutions to which will require human actions and engagements, modernity separates people from climate change in a number of ways. On the other, while amodern or more-than-human concepts of multiple and relational agency are more consistent with the empirical evidence of humans being deeply embedded in earth surface processes, these approaches ...


Engaging Creative Communities In An Industrial City Setting, Chris Gibson, Ben Gallan, Andrew Warren Dec 2012

Engaging Creative Communities In An Industrial City Setting, Chris Gibson, Ben Gallan, Andrew Warren

Chris Gibson

Much has been said about how ‘creativity’ might infuse policymaking and planning – especially in the wake of popular bestsellers by Richard Florida and Charles Landry on ‘creative places’ and the ‘creative class’ (the latter a supposed demographic group associated with creative industries such as film, design and music, who are said to be the key to the economic fortunes of cities). Creativity, it is said, can be facilitated in particular urban environments, given the right preconditions such as ‘hip’ inner-city precincts, café culture and walkable dense clusters of design firms and retail and residential spaces. The common argument is that ...


Living Together But Apart: Material Geographies Of Everyday Sustainability In Extended Family Households, Natascha Klocker, Chris Gibson, Erin Borger Dec 2012

Living Together But Apart: Material Geographies Of Everyday Sustainability In Extended Family Households, Natascha Klocker, Chris Gibson, Erin Borger

Chris Gibson

In the Industrialized West, ageing populations and cultural diversity-combined with rising property prices and extensive years spent in education-have been recognized as diverse factors driving increases in extended family living. At the same time, there is growing awareness that household size is inversely related to per capita resource consumption patterns, and that urgent problems of environmental sustainability are negotiated, on a day-to-day basis (and often unconsciously), at the household level. This paper explores the sustainability implications of everyday decisions to fashion, consume, and share resources around the home, through the lens of extended family households. Through interviews with extended family ...


Trial By Fire: Natural Hazards, Mixed-Methods And Cultural Research, Christine Eriksen, Nicholas J. Gill, Ross A. Bradstock Dec 2012

Trial By Fire: Natural Hazards, Mixed-Methods And Cultural Research, Christine Eriksen, Nicholas J. Gill, Ross A. Bradstock

Christine Eriksen

This paper considers the issues of research 'relevance' and 'use' to reflect upon a cultural geography research project on bushfire that did not begin with any specific aim of being useful to policy makers but which has garnered considerable and ongoing interest from a broad audience. It provides an example of how the integration of quantitative and qualitative research methods and data can enhance research into cultural aspects of natural hazards whilst simultaneously playing a key role in ensuring that the research results are of interest to a wide range of groups. Using a mixed-methods research approach was found to ...


The Art Of Learning: Wildfire, Amenity Migration And Local Environmental Knowledge, Christine Eriksen, T Prior Dec 2012

The Art Of Learning: Wildfire, Amenity Migration And Local Environmental Knowledge, Christine Eriksen, T Prior

Christine Eriksen

Communicating the need to prepare well in advance of the wildfire season is a strategic priority for wildfire management agencies worldwide. However, there is considerable evidence to suggest that although these agencies invest significant effort towards this objective in the lead up to each wildfire season, landholders in at-risk locations often remain under-prepared. One reason for the poor translation of risk information materials into actual preparation may be attributed to the diversity of people now inhabiting wildfire-prone locations in peri-urban landscapes. These people hold widely varying experiences, beliefs, attitudes and values relating to wildfire, which influence their understanding and interpretation ...


The Two-Faced Nature Of Small Heat Shock Proteins: Amyloid Assembly And The Inhibition Of Fibril Formation. Relevance To Disease States, Heath W. Ecroyd, S Meehan, John A. Carver Dec 2012

The Two-Faced Nature Of Small Heat Shock Proteins: Amyloid Assembly And The Inhibition Of Fibril Formation. Relevance To Disease States, Heath W. Ecroyd, S Meehan, John A. Carver

Heath Ecroyd

The ability of small heat-shock proteins (sHsps) such as alphaB-crystallin to inhibit the amorphous (disordered) aggregation of varied target proteins in a chaperone-like manner has been well described. The mechanistic details of this action are not understood. Amyloid fibril formation is an alternative off-folding pathway that leads to highly ordered beta-sheet-containing aggregates. Amyloid fibril formation is associated with a broad range of protein conformational diseases such as Alzhiemer's, Parkinson's and Huntington's and sHsp expression is elevated in the protein deposits that are characteristic of these disease states. The ability of sHsps to prevent fibril formation has been ...


Molecular Dynamics Analysis Of Apolipoprotein-D - Lipid Hydroperoxide Interactions: Mechanism For Selective Oxidation Of Met-93, Aaron J. Oakley, Surabhi Bhatia, Heath Ecroyd, Brett Garner Dec 2012

Molecular Dynamics Analysis Of Apolipoprotein-D - Lipid Hydroperoxide Interactions: Mechanism For Selective Oxidation Of Met-93, Aaron J. Oakley, Surabhi Bhatia, Heath Ecroyd, Brett Garner

Heath Ecroyd

Background: Recent studies suggest reduction of radical-propagating fatty acid hydroperoxides to inert hydroxides by interaction with apolipoprotein-D (apoD) Met93 may represent an antioxidant function for apoD. The nature and structural consequences of this selective interaction are unknown. Methodology/Principal Findings: Herein we used molecular dynamics (MD) analysis to address these issues. Longtimescale simulations of apoD suggest lipid molecules are bound flexibly, with the molecules free to explore multiple conformations in a binding site at the entrance to the classical lipocalin ligand-binding pocket. Models of 5s- 12s- and 15s hydroperoxyeicosatetraenoic acids were created and the lipids found to wrap around Met93 ...


Monotremes Provide A Key To Understanding The Evolutionary Significance Of Epididymal Sperm Maturation, Brett Nixon, Russell Jones, Jean-Louis Dacheux, Heath Ecroyd Dec 2012

Monotremes Provide A Key To Understanding The Evolutionary Significance Of Epididymal Sperm Maturation, Brett Nixon, Russell Jones, Jean-Louis Dacheux, Heath Ecroyd

Heath Ecroyd

"It has been widely accepted that mammalian spermatozoa are infertile when they leave the testes and require a period of maturation in both the epididymis and the female reproductive tract before acquiring the ability to fertilize an oocyte. However, the necessity for such a complex process of posttesticular sperm maturation appears to be unique to mammals because it is well established that these processes do not directly influence the fertilizing ability of the spermatozoa of birds, reptiles, and other lower vertebrates. Because of their key evolutionary position and form of reproduction, we contend that monotremes (platypus and echidna) provide a ...