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Full-Text Articles in Physical Sciences and Mathematics

Dilemma: Increase In Human Food Production Or Use Of Grasslands For Environmental And / Or Social Purposes, A. D. Meister Jan 2022

Dilemma: Increase In Human Food Production Or Use Of Grasslands For Environmental And / Or Social Purposes, A. D. Meister

IGC Proceedings (1993-2023)

In the title for this paper we find three major objectives: to feed the world, sustain the environment and provide resources for social purposes, and a dilemma. Even though the word ‘dilemma’ usually implies choice between undesirable alternatives, it is obvious that the alternatives here are not undesirable. Is the dilemma then, that we can only do one at the time, or that the consequences of favouring one over the other can lead to undesirable outcomes? It is my opinion that we are talking about the latter interpretation. It is the foreclosing of options by allowing one objective to dominate …


The Development And Prospect Of Chinese Grassland Economic System, Fuzeng H. Jan 2022

The Development And Prospect Of Chinese Grassland Economic System, Fuzeng H.

IGC Proceedings (1993-2023)

China is a country with an old agriculture civilization of the world. The arrangement of the crop and pasture area had developed from Han and Tang dynasty. (From A.C 206.to AD 907). Chinese livestock economic had undergone the winding development for a thousand years of feudal society, however, It still belong to a phase of the loose private ownership. From 1949 when The People's Republic of China was founded, the pasture was nationalized and collective management. Since 1980s, the planned economic changed into the market economic gradually. The pasture was public ownership, but management by contract, paid utilization and unchanged …


Contextual Factors In The Management Of Common Grazing Lands: Lessons From Mongolia And Northwestern China, R. Mearns Jan 2022

Contextual Factors In The Management Of Common Grazing Lands: Lessons From Mongolia And Northwestern China, R. Mearns

IGC Proceedings (1993-2023)

Seen in a global perspective, pastoral development is now increasingly motivated by social and environmental objectives rather than by production- or output-orientated objectives. Attention is shifting towards a broader concern with sustainability, both of grasslands, and of the livelihoods of those who rely on them (de Haan et al, 1997, Fratkin and Mearns forthcoming). Quite how these twin sustainability objectives may be achieved in particular contexts, however, is an empirical question. Drawing on examples from a diverse range of natural grassland-based livestock production systems under economic transition in Mongolia and northwestern China, this summary paper aims to show how an …


De-Intensification Of Grasslands: Current State And Trends, Michael Duru, Bernard Hubert Jan 2022

De-Intensification Of Grasslands: Current State And Trends, Michael Duru, Bernard Hubert

IGC Proceedings (1993-2023)

De-intensified use of grasslands, and more generally of the livestock systems they support, has been triggered by a growing sensitivity of citizens to environmental quality (nitrogen) and quality of animal products, and by the warnings addressed to political authorities by scientists about the environmental consequences of economic imbalances (decreasing biodiversity, drop in soil fertility, greenhouse effect), and in particular of food overproduction in Europe.

From an ecological standpoint, grassland de-intensification must be envisaged whenever the techniques implemented disrupt resource sustainability. The grassland resource itself may be at risk when a rate of vegetation offtake by herbivores that is incompatible with …


De-Intensification Of Grasslands: Understanding The Processes To Find The Balance, K. C. Hodgkinson Jan 2022

De-Intensification Of Grasslands: Understanding The Processes To Find The Balance, K. C. Hodgkinson

IGC Proceedings (1993-2023)

There is a growing trend in Australia and other developed countries for deintensification of animal production from grasslands and for grasslands to be used for purposes other than livestock grazing. These shifts are occurring for a variety of reasons including unsustainable land management practices, environmental pollution, loss of conservation value, poor commodity prices and declining rural infra-structure and communities. In Australia, the shifts are under way in agricultural grasslands, where sown pastures occur in a matrix of semi-natural woodlands, but less so in the other three major natural grasslands that forms the arid and semi-arid rangelands.

The conversion of natural …


Chicago Community Area Data, 1930-2010, Nate Falling, Jacob Nelson, Miguel Torres, Richard T. Melstrom Jan 2022

Chicago Community Area Data, 1930-2010, Nate Falling, Jacob Nelson, Miguel Torres, Richard T. Melstrom

School of Environmental Sustainability: Faculty Publications and Other Works

We are releasing a set of community area
statistics collected from fact book and census
profile data series. These statistics are in the file
Chicago_Community_Area_Data_1930-2010,
which is available from the attached dataset. The statistics do not reflect all of the
data contained in the historical sources.
Additional digitized data can be found at
https://robparal.com/chicago-data/.


Finding Triangular Cayley Maps With Graph Touring, Hannah Hendrickson Jan 2022

Finding Triangular Cayley Maps With Graph Touring, Hannah Hendrickson

Honors Program Theses

We develop a method for determining whether certain kinds of Cayley maps can exist by using multi-digraph representations of the data in the Cayley maps. Euler tours of these multi-digraphs correspond exactly to the permutations which define Cayley maps. We also begin to classify which 3-regular multi-digraphs have "non-backtracking" Euler tours in general.


Cloud Radiative Effects On Mjo Development In Dynamo, Qi Hu, Zihang Han, Shuguang Wang Jan 2022

Cloud Radiative Effects On Mjo Development In Dynamo, Qi Hu, Zihang Han, Shuguang Wang

Department of Earth and Atmospheric Sciences: Faculty Publications

Observed Madden–Julian oscillation (MJO) events are examined with the aid of regional model simulations to understand the role of cloud radiative effects in the MJO development. The importance of this role is demonstrated by the absence of the MJO in the model simulations that contain no cloud radiative effects. Comparisons of model simulations with and without the cloud radiative effects and observation help identify the major processes arising from those effects. Those processes develop essentially from heating in the upper troposphere due to shortwave absorption within anvil clouds in the upper troposphere and the convergence of longwave radiation in the …


Identifying Membrane Lateral Organization By Contrast-Matched Small Angle Neutron Scattering, Mitchell Dipasquale, Michael H.L. Nguyen, Stuart R. Castillo, Frederick A. Heberle, Drew Marquardt Jan 2022

Identifying Membrane Lateral Organization By Contrast-Matched Small Angle Neutron Scattering, Mitchell Dipasquale, Michael H.L. Nguyen, Stuart R. Castillo, Frederick A. Heberle, Drew Marquardt

Chemistry and Biochemistry Publications

Lipid domains in model membranes are routinely studied to provide insight into the physical interactions that drive raft formation in cellular membranes. Using small angle neutron scattering, contrast-matching techniques enable the detection of lipid domains ranging from tens to hundreds of nanometers which are not accessible to other techniques without the use of extrinsic probes. Here, we describe a probe-free experimental approach and model-free analysis to identify lipid domains in freely floating vesicles of ternary phase separating lipid mixtures.


A Comprehensive Literature Review On Convolutional Neural Networks, Ehsan Ur Rahman Mohammed, Narasimha Reddy Soora Dr., Sharfuddin Waseem Mohammed Jan 2022

A Comprehensive Literature Review On Convolutional Neural Networks, Ehsan Ur Rahman Mohammed, Narasimha Reddy Soora Dr., Sharfuddin Waseem Mohammed

Computer Science Publications

The fields of computer vision and image processing from their initial days have been dealing with the problems of visual recognition. Convolutional Neural Networks (CNNs) in machine learning are deep architectures built as feed-forward neural networks or perceptrons, which are inspired by the research done in the fields of visual analysis by the visual cortex of mammals like cats. This work gives a detailed analysis of CNNs for the computer vision tasks, natural language processing, fundamental sciences and engineering problems along with other miscellaneous tasks. The general CNN structure along with its mathematical intuition and working, a brief critical commentary …


Long-Read Sequencing Of The Zebrafish Genome Reorganizes Genomic Architecture, Yelena Chernyavskaya, Xiaofei Zhang, Jinze Liu, Jessica Blackburn Jan 2022

Long-Read Sequencing Of The Zebrafish Genome Reorganizes Genomic Architecture, Yelena Chernyavskaya, Xiaofei Zhang, Jinze Liu, Jessica Blackburn

Biostatistics Publications

Background

Nanopore sequencing technology has revolutionized the field of genome biology with its ability to generate extra-long reads that can resolve regions of the genome that were previously inaccessible to short-read sequencing platforms. Over 50% of the zebrafish genome consists of difficult to map, highly repetitive, low complexity elements that pose inherent problems for short-read sequencers and assemblers.

Results

We used long-read nanopore sequencing to generate a de novo assembly of the zebrafish genome and compared our assembly to the current reference genome, GRCz11. The new assembly identified 1697 novel insertions and deletions over one kilobase in length and placed …


On The Use Of High-Frequency Surface Wave Oceanographic Research Radars As Bistatic Single-Frequency Oblique Ionospheric Sounders, Stephen R. Kaeppler, Ethan S. Miller, Daniel Cole, Teresa Updyke Jan 2022

On The Use Of High-Frequency Surface Wave Oceanographic Research Radars As Bistatic Single-Frequency Oblique Ionospheric Sounders, Stephen R. Kaeppler, Ethan S. Miller, Daniel Cole, Teresa Updyke

CCPO Publications

We demonstrate that bistatic reception of high-frequency oceanographic radars can be used as single-frequency oblique ionospheric sounders. We develop methods that are agnostic of the software-defined radio system to estimate the group range from the bistatic observations. The group range observations are used to estimate the virtual height and equivalent vertical frequency at the midpoint of the oblique propagation path. Uncertainty estimates of the virtual height and equivalent vertical frequency are presented. We apply this analysis to observations collected from two experiments run at two locations in different years, but utilizing similar software-defined radio data collection systems. In the first …


Cyber Whistleblowers: The Black Sheep Of Whistleblowing?, Andrew Wisniewski Jr. Jan 2022

Cyber Whistleblowers: The Black Sheep Of Whistleblowing?, Andrew Wisniewski Jr.

Cybersecurity Undergraduate Research Showcase

From the Introduction:

Contrary to popular belief, this paper argues that cyber whistleblowing can contribute to a greater cyber security posture. However, this requires the development of clearer legal obligations and protections for cyber whistleblowers. This paper will explore the psychology behind whistleblowing, the effectiveness of whistleblowing in a cybersecurity context, how to create a safer and more transparent environment for whistleblowers and companies, and how current laws contribute to cyber whistleblowing.


Healing Earth In A Time Of Crisis: Curriculum For Integral Ecology, Caleb Steindam Jan 2022

Healing Earth In A Time Of Crisis: Curriculum For Integral Ecology, Caleb Steindam

Dissertations

This intrinsic multiple case study examined secondary- and university-level educators’ experiences teaching with Healing Earth, a curriculum developed by the International Jesuit Ecology Project at Loyola University Chicago, which merges scientific, social, spiritual, and ethical analyses of pressing ecological issues. Based on the conceptual framework of integral ecology, Healing Earth is a response to Pope Francis’s (2015a) call for “a new way of thinking about human beings, life, society and our relationship with nature” (§215).

This study primarily consisted of in-depth interviews with educators who have used Healing Earth in a variety of secondary and post-secondary Catholic educational contexts. A …


Rhodium-Catalyzed Decarbonylation Of Aroyl Chlorides, Wiktoria M. Koza Jan 2022

Rhodium-Catalyzed Decarbonylation Of Aroyl Chlorides, Wiktoria M. Koza

Dissertations

The development of efficient strategies for the synthesis of aryl–halogen bonds is highly desirable due to the prevalence of these moieties in pharmaceuticals, agrochemicals, and organic synthesis. Although there are numerous applications of aryl chlorides in chemistry, an efficient strategy for the preparation of these molecules is underdeveloped. Transition metal-catalyzed decarbonylation provides an efficient and selective approach for aryl–halogen bond formation. There has been significant progress in the development of new decarbonylation strategies, particularly involving aldehydes for the synthesis of new carbon–hydrogen (C–H) bonds or for cross-coupling reactions. However, transition metal-catalyzed decarbonylation methods for carbon–halogen (C–X) bond formation have been …


Water Current, Volume 54, No. 1, Winter 2022 Jan 2022

Water Current, Volume 54, No. 1, Winter 2022

Water Current Newsletter

No abstract provided.


Infrared Dielectric Functions And Brillouin Zone Center Phonons Of Α-Ga2O3 Compared To Α-Al2O3, Megan Stokey, Rafal Korlacki, Matthew J. Hilfiker, Sean Knight, Steffen Richter, Vanya Darakchieva, Riena Jinno, Yongjin Cho, Huili Grace Xing, Debdeep Jena, Yuichi Oshima, Kamruzzaman Khan, Elaheh Ahmadi, Mathias Schubert Jan 2022

Infrared Dielectric Functions And Brillouin Zone Center Phonons Of Α-Ga2O3 Compared To Α-Al2O3, Megan Stokey, Rafal Korlacki, Matthew J. Hilfiker, Sean Knight, Steffen Richter, Vanya Darakchieva, Riena Jinno, Yongjin Cho, Huili Grace Xing, Debdeep Jena, Yuichi Oshima, Kamruzzaman Khan, Elaheh Ahmadi, Mathias Schubert

Department of Electrical and Computer Engineering: Faculty Publications

We determine the anisotropic dielectric functions of rhombohedral α-Ga2O3 by far-infrared and infrared generalized spectroscopic ellipsometry and derive all transverse optical and longitudinal optical phonon mode frequencies and broadening parameters. We also determine the high-frequency and static dielectric constants. We perform density functional theory computations and determine the phonon dispersion for all branches in the Brillouin zone, and we derive all phonon mode parameters at the Brillouin zone center including Raman-active, infrared-active, and silent modes. Excellent agreement is obtained between our experimental and computation results as well as among all previously reported partial information from experiment …


Data Science Applied To Discover Ancient Minoan-Indus Valley Trade Routes Implied By Commonweight Measures, Peter Revesz Jan 2022

Data Science Applied To Discover Ancient Minoan-Indus Valley Trade Routes Implied By Commonweight Measures, Peter Revesz

CSE Conference and Workshop Papers

This paper applies data mining of weight measures to discover possible long-distance trade routes among Bronze Age civilizations from the Mediterranean area to India. As a result, a new northern route via the Black Sea is discovered between the Minoan and the Indus Valley civilizations. This discovery enhances the growing set of evidence for a strong and vibrant connection among Bronze Age civilizations.


Ultrafast Dynamics Of Nitro−Nitrite Rearrangement And Dissociation In Nitromethane Cation, Mi'kayla D. Word, Hugo Andres Lopez Pena, Derrick Ampadu Boateng, Shane L. Mcpherson, Gennady L. Gutsev, Lavrenty Gutsev, Ka Un Lao, Katharine M. Tibbetts Jan 2022

Ultrafast Dynamics Of Nitro−Nitrite Rearrangement And Dissociation In Nitromethane Cation, Mi'kayla D. Word, Hugo Andres Lopez Pena, Derrick Ampadu Boateng, Shane L. Mcpherson, Gennady L. Gutsev, Lavrenty Gutsev, Ka Un Lao, Katharine M. Tibbetts

Chemistry Publications

We report new insights into the ultrafast rearrange- ment and dissociation dynamics of nitromethane cation (NM+) using pump−probe measurements, electronic structure calculations, and ab initio molecular dynamics simulations. The “roaming” nitro−nitrite rearrangement (NNR) pathway involving large- amplitude atomic motion, which has been previously described for neutral nitromethane, is demonstrated for NM+. Excess energy resulting from initial population of the electronically excited D2 state of NM+ upon strong-field ionization provides the necessary energy to initiate NNR and subsequent dissociation into NO+. Both pump−probe measurements and molecular dynamics simulations are consistent with the completion of NNR within 500 fs of ionization with …


Generation Of Nanomaterials By Reactive Laser Synthesis In Liquid, Laysa M. Frias Batista, Ashish B. Nag, Victoria K. Meader, Katharine M. Tibbetts Jan 2022

Generation Of Nanomaterials By Reactive Laser Synthesis In Liquid, Laysa M. Frias Batista, Ashish B. Nag, Victoria K. Meader, Katharine M. Tibbetts

Chemistry Publications

Nanomaterials with tailored structures and surface chemistry are in high demand, as these materials play increasingly important roles in biology, catalysis, energy storage, and manu- facturing. Their heightened demand has attracted attention towards the development of syn- thesis routes, particularly, laser-synthesis techniques. These efforts drove the refinement of laser ablation in liquid (LAL) and related methods over the past two decades, and have led to the emergence of reactive laser-synthesis techniques that exploit these methods’ character- istic, non-equilibrium conditions. Reactive laser-synthesis approaches foster unique chemical reactions that enable the formation of composite products like multimetallic nanoparticles, supported nanostructures, and complex …


A Modulated Structure Derived From The Xa-Type Mn2Rusn Heusler Compound, Xingzhong Li, Wen-Yong Zhang, Ralph Skomski, David J. Sellmyer Jan 2022

A Modulated Structure Derived From The Xa-Type Mn2Rusn Heusler Compound, Xingzhong Li, Wen-Yong Zhang, Ralph Skomski, David J. Sellmyer

Nebraska Center for Materials and Nanoscience: Faculty Publications

A modulated structure derived from the inverse Heusler phase (the XA-type and the disordered variant L21B-type) has been observed in rapidly quenched Mn2RuSn ribbons. The powder X-ray diffraction pattern of the quenched ribbons can be indexed as an L21B-type structure. Electron diffraction patterns of the new structure mostly resemble those of the XA-type (and the disordered variant L21B-type) structure and additional reflections with denser spacing indicate a long periodicity. Orthogonal domains of the modulated structure were revealed by a selected-area electron diffraction pattern and the corresponding dark-field transmission electron microscopy images. The structure was …


Localization Effects And Anomalous Hall Conductivity In A Disordered 3d Ferromagnet, Paul M. Shand, Y. Moua, G. Baker, Shah R. Valloppilly, Pavel V. Lukashev, Parashu Kharel Jan 2022

Localization Effects And Anomalous Hall Conductivity In A Disordered 3d Ferromagnet, Paul M. Shand, Y. Moua, G. Baker, Shah R. Valloppilly, Pavel V. Lukashev, Parashu Kharel

Nebraska Center for Materials and Nanoscience: Faculty Publications

We have prepared the Heusler alloy CoFeV0.5Mn0.5Si in bulk form via arc melting. CoFeV0.5Mn0.5Si is ferromagnetic with a Curie temperature of 657 K. The longitudinal resistivity exhibits a minimum at 150 K, which is attributable to competition between quantum interference corrections at low temperatures and inelastic scattering at higher temperatures. The magnetoresistance (MR) is positive and nearly linear at low temperatures and becomes negative at temperatures close to room temperature. The positive MR in the quantum correction regime is evidence of the presence of the enhanced electron interaction as a contributor to …


The “Office Of The Ciso”: A Framework For Chief Information Security Officers, Yael Nagler, Christophe Veltsos Jan 2022

The “Office Of The Ciso”: A Framework For Chief Information Security Officers, Yael Nagler, Christophe Veltsos

Computer Information Science Department Publications

As we enter 2022, cybersecurity continues to challenge corporations and their CISOs. The sophistication of cyberthreats coupled with an evolving digital landscape has resulted in increased complexity and expanded responsibilities for the CISO. Simply put, there is greater scrutiny, greater regulation, greater complexity, and greater scope than ever before. To respond to these changes, CISOs must organize their “Office of the CISO” to meet the expectations and deliver for their organizations. Whether the CISO has a staff of three or thirty and whether they are prepared or not, these elements are being increasingly expected of CISOs. You can think of …


Increased Caribbean Seismicity And Volcanism During Minima In Earth's Rotation Rate: Search For A Physical Mechanism And A 2030 Forecast, Roger Bilham, Walter Szeliga, David Mencin, Rebecca Bendick Jan 2022

Increased Caribbean Seismicity And Volcanism During Minima In Earth's Rotation Rate: Search For A Physical Mechanism And A 2030 Forecast, Roger Bilham, Walter Szeliga, David Mencin, Rebecca Bendick

Geological Sciences Faculty Scholarship

Three quarters of all Mw ≥ 6.6 earthquakes and volcanic eruptions surrounding the Caribbean plate occur preferentially during periods of decadal minima in Earth’s angular spin velocity. This correlation is revealed most clearly as a 4–6 years phase lag following the first derivative of the length of the day (LOD), Earth’s angular deceleration. We show that local strains and displacements resulting from oblateness changes, or plate boundary stresses associated with changes in tropical rotation rates are orders of magnitude lower than those typically associated with earthquake or volcano triggering. Notwithstanding the absence of a satisfactory causal physical mechanism, the relationship …


Understanding California's 2022 Energy Code: Blog 1, Gabriella Medina, Darbi Berry Jan 2022

Understanding California's 2022 Energy Code: Blog 1, Gabriella Medina, Darbi Berry

San Diego Regional Climate Collaborative

When thinking about the built environment, it is easy to overlook the influence structures have on our communities' quality of life. Buildings are relics of the past or symbols of modernity. They are tangible evidence of our society's investment in people's health, the environment and a resilient economy. Buildings play a crucial role over energy usage, urban heat impacts, and overall greenhouse gas emissions.


Quick Guide To The 2022 Energy Code: Blog 2, Gabriella Medina, Darbi Berry Jan 2022

Quick Guide To The 2022 Energy Code: Blog 2, Gabriella Medina, Darbi Berry

San Diego Regional Climate Collaborative

There are a wide range of updates to the 2022 Energy Code; however, there are four categories of top priority for industry professionals and end-use stakeholders as California strengthens compliance standards: electric heat pump technology, electric-ready requirements, solar photovoltaic systems and battery storage standards, and strong ventilation standards.


Sustainability & (Em)Powering Community Based Action In Chula Vista, Gabriella Medina, Darbi Berry Jan 2022

Sustainability & (Em)Powering Community Based Action In Chula Vista, Gabriella Medina, Darbi Berry

San Diego Regional Climate Collaborative

The City of Chula Vista (Chula Vista / the City) has already begun to experience the localized impacts of climate change through record-breaking heat waves, droughts, and wildfires. In response to the impacts of climate change posing a threat to Chula Vista residents’ quality of life, the City declared a climate emergency in March 2022. This declaration advanced the City’s commitment to update its Greenhouse Gas (GHG) reduction goals, strengthen existing efforts like the City Operations Sustainability Plan, and encourage new City-wide and voluntary actions by residents and businesses. The Chula Vista DIY Sustainable Home Toolkit (Toolkit) is a best …


Understanding The Intersections Of The Lgbtq+ Community & Climate Change, Annabel Gong, Darbi Berry Jan 2022

Understanding The Intersections Of The Lgbtq+ Community & Climate Change, Annabel Gong, Darbi Berry

San Diego Regional Climate Collaborative

In this blog, we will explore these LGBTQ+ community relationships as they relate to environmental justice, relationships and access to the outdoors, and community representation in the environmental science field.


Laying The Groundwork For Equity-First Climate Adaptation, Michelle Robidas, Darbi Berry Jan 2022

Laying The Groundwork For Equity-First Climate Adaptation, Michelle Robidas, Darbi Berry

San Diego Regional Climate Collaborative

SDRCC is excited to share the first post of our 2-part Climate Adaptation Blog Series "Laying the Groundwork for Equity-First Climate Adaptation." This blog post gives a high-level introduction to SDRCC and SANDAG's Equity-First Approach to Climate Adaptation guidance document. Readers will learn strategies to identify social equity communities, build community capacity, and link adaptation planning efforts to the four dimensions of equity.


Approaches And Strategies To Integrate Equity Into Adaptation Planning, Michelle Robidas, Darbi Berry Jan 2022

Approaches And Strategies To Integrate Equity Into Adaptation Planning, Michelle Robidas, Darbi Berry

San Diego Regional Climate Collaborative

SDRCC is excited to share the second post of our 2-part Climate Adaptation Blog Series "Approaches and Strategies to Integrate Equity into Adaptation Planning." Building off of our first adaptation blog, readers will learn about equitable stakeholder engagement, identifying starting point vulnerabilities, how to conduct a vulnerability assessment, and opportunities to integrate equity into all phases of climate adaptation projects.