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Articles 1291 - 1320 of 294627

Full-Text Articles in Physical Sciences and Mathematics

Limonene Enantiomeric Ratios From Anthropogenic And Biogenic Emission Sources, Shan Gu, Wentai Luo, Avisa Charmchi, Kevin J. Mcwhirter, Todd Rosenstiel, James F. Pankow Mar 2024

Limonene Enantiomeric Ratios From Anthropogenic And Biogenic Emission Sources, Shan Gu, Wentai Luo, Avisa Charmchi, Kevin J. Mcwhirter, Todd Rosenstiel, James F. Pankow

Chemistry Faculty Publications and Presentations

Emissions from volatile chemical products (VCPs) have been identified as contributors to air quality degradation in urban areas. Limonene can be a tracer compound for VCPs containing fragrances in densely populated regions, but limonene is also emitted from conifers that are planted in urban areas. This creates challenges for using limonene to estimate VCP emissions. In this study, the −/+ enantiomeric ratios of limonene from VCP and conifer emission sources were quantified to evaluate if this measurement could be used to aid in source apportionment and emission inventory development. Samples were analyzed using a gas chromatograph equipped with a chiral …

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The Α-Crystallin Chaperones Undergo A Quasi-Ordered Co-Aggregation Process In Response To Saturating Client Interaction, Kirsten Lampi, Adam P. Miller, Susan E. O'Neill, Steve L. Reichow Mar 2024

The Α-Crystallin Chaperones Undergo A Quasi-Ordered Co-Aggregation Process In Response To Saturating Client Interaction, Kirsten Lampi, Adam P. Miller, Susan E. O'Neill, Steve L. Reichow

Chemistry Faculty Publications and Presentations

Small heat shock proteins (sHSPs) are ATP-independent chaperones vital to cellular proteostasis, preventing protein aggregation events linked to various human diseases including cataract. The α-crystallins, αA-crystallin (αAc) and αB-crystallin (αBc), represent archetypal sHSPs that exhibit complex polydispersed oligomeric assemblies and rapid subunit exchange dynamics. Yet, our understanding of how this plasticity contributes to chaperone function remains poorly understood. This study investigates structural changes in αAc and αBc during client sequestration under varying degree of chaperone saturation. Using biochemical and biophysical analyses combined with single-particle electron microscopy (EM), we examined αAc and αBc in their apo-states and at various stages of …

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Using Flipped Classroom Modules To Facilitate Higher Order Learning In Undergraduate Organic Chemistry, Lauren R. Holloway, Tabitha Miller, Bryce Da Camara, Paul M. Bogie, Briana L. Hickey, Jack Barbera, Angie L. Lopez, Multiple Additional Authors Mar 2024

Using Flipped Classroom Modules To Facilitate Higher Order Learning In Undergraduate Organic Chemistry, Lauren R. Holloway, Tabitha Miller, Bryce Da Camara, Paul M. Bogie, Briana L. Hickey, Jack Barbera, Angie L. Lopez, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

In an ongoing effort to incorporate active learning and promote higher order learning outcomes in undergraduate organic chemistry, a hybrid (“flipped”) classroom structure has been used to facilitate a series of collaborative activities in the first two courses of the lower division organic chemistry sequence. An observational study of seven classes over a five-year period reveals there is a strong correlation between performance on the in-class activities and performance on the final exam across all classes; however, a significant number of students in these courses continue to struggle on both the in-class activities and final exam. The Activity Engagement Survey …

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Comment On “Spectral Shifts In General Relativity,” [Am. J. Phys. 62(10), 903–907 (1994)], Joseph D. Romano, Teviet Creighton Mar 2024

Comment On “Spectral Shifts In General Relativity,” [Am. J. Phys. 62(10), 903–907 (1994)], Joseph D. Romano, Teviet Creighton

Physics and Astronomy Faculty Publications and Presentations

No abstract provided.

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Powerful Radio Sources In The Southern Sky. Iii. First Results Of The Optical Spectroscopic Campaign, A. García-Pérez, H. A. Peña-Herazo, A. Jimenez-Gallardo, V. Chavushyan, F. Massaro, S. V. White, A. Capetti, B. Balmaverde, W. R. Forman, Juan P. Madrid Mar 2024

Powerful Radio Sources In The Southern Sky. Iii. First Results Of The Optical Spectroscopic Campaign, A. García-Pérez, H. A. Peña-Herazo, A. Jimenez-Gallardo, V. Chavushyan, F. Massaro, S. V. White, A. Capetti, B. Balmaverde, W. R. Forman, Juan P. Madrid

Physics and Astronomy Faculty Publications and Presentations

We recently built the G4Jy-3CRE catalog of extragalactic radio sources. This catalog lists 264 powerful radio sources selected with similar criteria to those of the revised Third Cambridge Catalog, but visible from the Southern Hemisphere. A literature search revealed that 119 sources in the G4Jy-3CRE catalog (i.e., 45%) lack a firm spectroscopic redshift measurement. Here, we present a campaign aimed at acquiring optical spectra of G4Jy-3CRE sources and measuring their redshifts. We used single-slit observations obtained with the Víctor Blanco Telescope, the New Technology Telescope, the Southern Astrophysical Research Telescope, and the 2.1 m telescope of the Observatorio Astronómico Nacional …

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Investigating Communication Of Findings In Environmental Impact Assessment And Developing A Research Agenda For Improvement, Alan Bond, Francois Retief, Angus Morrison-Saunders, Jenny Pope, Reece C. Alberts, Claudine Roos, Dirk Cilliers Mar 2024

Investigating Communication Of Findings In Environmental Impact Assessment And Developing A Research Agenda For Improvement, Alan Bond, Francois Retief, Angus Morrison-Saunders, Jenny Pope, Reece C. Alberts, Claudine Roos, Dirk Cilliers

Research outputs 2022 to 2026

Environmental Impact Assessment (EIA) aims to embed consideration of the significance of predicted environmental consequences (the findings) of proposed developments into approval decision making. Achieving this aim relies on adequate communication of the findings of the EIA to the stakeholders, especially the decision makers responsible for the approval decision. However, the naïve assumption that this communication of findings can be effectively achieved through the publication of a written report pervades legislation worldwide, despite decades of evidence to the contrary. As a first step towards improving such communication, this research identifies the contingent conditions associated with effectively transferring EIA findings from …

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A 2,000-Year Record Of Eelgrass (Zostera Marina L.) Colonization Shows Substantial Gains In Blue Carbon Storage And Nutrient Retention, Martin Dahl, Martin Gullström, Irene Bernabeu, Oscar Serrano, Carmen Leiva-Dueñas, Hans W. Linderholm, Maria E. Asplund, Mats Björk, Tinghai Ou, J. Robin Svensson, Elinor Andrén, Thomas Andrén, Sanne Bergman, Sara Braun, Anneli Eklöf, Zilvinas Ežerinskis, Andrius Garbaras, Petter Hällberg, Elin Löfgren, Malin E. Kylander, Pere Masqué, Justina Šapolaitė, Rienk Smittenberg, Miguel A. Mateo Mar 2024

A 2,000-Year Record Of Eelgrass (Zostera Marina L.) Colonization Shows Substantial Gains In Blue Carbon Storage And Nutrient Retention, Martin Dahl, Martin Gullström, Irene Bernabeu, Oscar Serrano, Carmen Leiva-Dueñas, Hans W. Linderholm, Maria E. Asplund, Mats Björk, Tinghai Ou, J. Robin Svensson, Elinor Andrén, Thomas Andrén, Sanne Bergman, Sara Braun, Anneli Eklöf, Zilvinas Ežerinskis, Andrius Garbaras, Petter Hällberg, Elin Löfgren, Malin E. Kylander, Pere Masqué, Justina Šapolaitė, Rienk Smittenberg, Miguel A. Mateo

Research outputs 2022 to 2026

Assessing historical environmental conditions linked to habitat colonization is important for understanding long-term resilience and improving conservation and restoration efforts. Such information is lacking for the seagrass Zostera marina, an important foundation species across cold-temperate coastal areas of the Northern Hemisphere. Here, we reconstructed environmental conditions during the last 14,000 years from sediment cores in two eelgrass (Z. marina) meadows along the Swedish west coast, with the main aims to identify the time frame of seagrass colonization and describe subsequent biogeochemical changes following establishment. Based on vegetation proxies (lipid biomarkers), eelgrass colonization occurred about 2,000 years ago after geomorphological changes …

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Introducing Pour Points: Characteristics And Hydrological Significance Of A Rainfall-Concentrating Mechanism In A Water-Limited Woodland Ecosystem, Ashvath S. Kunadi, Tim Lardner, Richard P. Silberstein, Matthias Leopold, Nik Callow, Erik Veneklaas, Aryan Puri, Eleanor Sydney, Sally E. Thompson Mar 2024

Introducing Pour Points: Characteristics And Hydrological Significance Of A Rainfall-Concentrating Mechanism In A Water-Limited Woodland Ecosystem, Ashvath S. Kunadi, Tim Lardner, Richard P. Silberstein, Matthias Leopold, Nik Callow, Erik Veneklaas, Aryan Puri, Eleanor Sydney, Sally E. Thompson

Research outputs 2022 to 2026

The interception of rainfall by plant canopies alters the depth and spatial distribution of water arriving at the soil surface, and thus the location, volume, and depth of infiltration. Mechanisms like stemflow are known to concentrate rainfall and route it deep into the soil, yet other mechanisms of flow concentration are poorly understood. This study characterizes pour points, formed by the detachment of water flowing under a branch, using a combination of field observations in Western Australian banksia woodlands and rainfall simulation experiments on Banksia menziesii branches. We aim to establish the hydrological significance of pour points in a water-limited …

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Fixing Your Own Smells: Adding A Mistake-Based Familiarization Step When Teaching Code Refactoring, Ivan Wei Han Tan, Christopher M. Poskitt Mar 2024

Fixing Your Own Smells: Adding A Mistake-Based Familiarization Step When Teaching Code Refactoring, Ivan Wei Han Tan, Christopher M. Poskitt

Research Collection School Of Computing and Information Systems

Programming problems can be solved in a multitude of functionally correct ways, but the quality of these solutions (e.g. readability, maintainability) can vary immensely. When code quality is poor, symptoms emerge in the form of 'code smells', which are specific negative characteristics (e.g. duplicate code) that can be resolved by applying refactoring patterns. Many undergraduate computing curricula train students on this software engineering practice, often doing so via exercises on unfamiliar instructor-provided code. Our observation, however, is that this makes it harder for novices to internalise refactoring as part of their own development practices. In this paper, we propose a …

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Harnessing The Advances Of Meda To Optimize Multi-Puf For Enhancing Ip Security Of Biochips, Chen Dong, Xiaodong Guo, Sihuang Lian, Yinan Yao, Zhenyi Chen, Yang Yang, Zhanghui Liu Mar 2024

Harnessing The Advances Of Meda To Optimize Multi-Puf For Enhancing Ip Security Of Biochips, Chen Dong, Xiaodong Guo, Sihuang Lian, Yinan Yao, Zhenyi Chen, Yang Yang, Zhanghui Liu

Research Collection School Of Computing and Information Systems

Digital microfluidic biochips (DMFBs) have a significant stride in the applications of medicine and the biochemistry in recent years. DMFBs based on micro-electrode-dot-array (MEDA) architecture, as the next-generation DMFBs, aim to overcome drawbacks of conventional DMFBs, such as droplet size restriction, low accuracy, and poor sensing ability. Since the potential market value of MEDA biochips is vast, it is of paramount importance to explore approaches to protect the intellectual property (IP) of MEDA biochips during the development process. In this paper, an IP authentication strategy based on the multi-PUF applied to MEDA biochips is presented, called bioMPUF, consisting of Delay …

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Hypergraphs With Attention On Reviews For Explainable Recommendation, Theis E. Jendal, Trung Hoang Le, Hady Wirawan Lauw, Matteo Lissandrini, Peter Dolog, Katja Hose Mar 2024

Hypergraphs With Attention On Reviews For Explainable Recommendation, Theis E. Jendal, Trung Hoang Le, Hady Wirawan Lauw, Matteo Lissandrini, Peter Dolog, Katja Hose

Research Collection School Of Computing and Information Systems

Given a recommender system based on reviews, the challenges are how to effectively represent the review data and how to explain the produced recommendations. We propose a novel review-specific Hypergraph (HG) model, and further introduce a model-agnostic explainability module. The HG model captures high-order connections between users, items, aspects, and opinions while maintaining information about the review. The explainability module can use the HG model to explain a prediction generated by any model. We propose a path-restricted review-selection method biased by the user preference for item reviews and propose a novel explanation method based on a review graph. Experiments on …

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Numerical Simulations For Fractional Differential Equations Of Higher Order And A Wright-Type Transformation, Mariana Nacianceno, Tamer Oraby, Hansapani Rodrigo, Y. Sepulveda, Josef A. Sifuentes, Erwin Suazo, T. Stuck, J. Williams Mar 2024

Numerical Simulations For Fractional Differential Equations Of Higher Order And A Wright-Type Transformation, Mariana Nacianceno, Tamer Oraby, Hansapani Rodrigo, Y. Sepulveda, Josef A. Sifuentes, Erwin Suazo, T. Stuck, J. Williams

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

In this work, a new relationship is established between the solutions of higher fractional differential equations and a Wright-type transformation. Solutions could be interpreted as expected values of functions in a random time process. As applications, we solve the fractional beam equation, fractional electric circuits with special functions as external sources, and derive d’Alembert’s formula for the fractional wave equation. Due to this relationship, we present two methods for simulating solutions of fractional differential equations. The two approaches use the interpretation of the Caputo derivative of a function as a Wright-type transformation of the higher derivative of the function. In …

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Future-Proofing The Past: Artificial Intelligence In The Restoration Of Andalusian Architectural Heritage: A Case Study Of The Alhambra Palace, Granada, Spain, Kholoud Bader Hasan Ghaith Mar 2024

Future-Proofing The Past: Artificial Intelligence In The Restoration Of Andalusian Architectural Heritage: A Case Study Of The Alhambra Palace, Granada, Spain, Kholoud Bader Hasan Ghaith

Theses

This thesis explains the contribution of artificial intelligence in heritage restoration as an icon of Andalusian architecture by using the Alhambra as an example. The task of sustaining heritage is increasing dramatically due to the accumulation of heritage assets and the need for modern and innovative operations to cope with preservation tasks. Therefore, this thesis reviews the role of artificial intelligence in improving the restoration operation to improve accuracy and efficiency. I applied the case study as a scientific methodology to explain this work to overcome scientific and subjective obstacles, such as scarce data and software integration while explaining the …

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Marketing Video Games To Aging Demographics: A Generational Profile Analysis, Brinna Louise Ball Mar 2024

Marketing Video Games To Aging Demographics: A Generational Profile Analysis, Brinna Louise Ball

Theses

Marketing video games to aging demographics like Baby Boomers, Generation X, and Millennials requires a unique approach by video game studios and consumer products divisions alike. The strategies employed for younger generations such as Generation Z and Generation Alpha differ from conventional methods, requiring a fresh outlook and a need for more innovative and inventive approaches. To comprehend the current aging audience more effectively, it's essential to examine four crucial factors: accessibility, exposure, media habits, and motivations to play video games. Examining these factors by generation, we can better grasp how to effectively market video games to these demographics. It's …

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Seasonal Variability And Predictability Of Monsoon Precipitation In Southern Africa, Matthew F. Horan, Fred Kucharski, Moetasim Ashfaq Mar 2024

Seasonal Variability And Predictability Of Monsoon Precipitation In Southern Africa, Matthew F. Horan, Fred Kucharski, Moetasim Ashfaq

Faculty Publications

Rainfed agriculture is the mainstay of economies across Southern Africa (SA), where most precipitation is received during the austral summer monsoon. This study aims to further our understanding of monsoon precipitation predictability over SA. We use three natural climate forcings, El Niño–Southern Oscillation, Indian Ocean Dipole (IOD), and the Indian Ocean Precipitation Dipole (IOPD)—the dominant precipitation variability mode—to construct an empirical model that exhibits significant skill over SA during monsoon in explaining precipitation variability and in forecasting it with a five-month lead. While most explained precipitation variance (50%–75%) comes from contemporaneous IOD and IOPD, preconditioning all three forcings is key …

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Transiam: Aggregating Multi-Modal Visual Features With Locality For Medical Image Segmentation, Xuejian Li, Shiqiang Ma, Junhai Xu, Jijun Tang, Shengfeng He, Fei Guo Mar 2024

Transiam: Aggregating Multi-Modal Visual Features With Locality For Medical Image Segmentation, Xuejian Li, Shiqiang Ma, Junhai Xu, Jijun Tang, Shengfeng He, Fei Guo

Research Collection School Of Computing and Information Systems

Automatic segmentation of medical images plays an important role in the diagnosis of diseases. On single-modal data, convolutional neural networks have demonstrated satisfactory performance. However, multi-modal data encompasses a greater amount of information rather than single-modal data. Multi-modal data can be effectively used to improve the segmentation accuracy of regions of interest by analyzing both spatial and temporal information. In this study, we propose a dual-path segmentation model for multi-modal medical images, named TranSiam. Taking into account that there is a significant diversity between the different modalities, TranSiam employs two parallel CNNs to extract the features which are specific to …

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Strongly Magnetized Accretion In Two Ultracompact Binary Systems, Thomas J. Maccarone, Thomas Kupfer, Edgar Najera Casarrubias, Liliana E. Rivera Sandoval, Aarran W. Shaw, Christoper T. Britt, Jan Van Roestel, David R. Zurek Mar 2024

Strongly Magnetized Accretion In Two Ultracompact Binary Systems, Thomas J. Maccarone, Thomas Kupfer, Edgar Najera Casarrubias, Liliana E. Rivera Sandoval, Aarran W. Shaw, Christoper T. Britt, Jan Van Roestel, David R. Zurek

Physics and Astronomy Faculty Publications and Presentations

We present the discoveries of two of AM CVn systems, Gaia14aae and SDSS J080449.49+161624.8, which show X-ray pulsations at their orbital periods, indicative of magnetically collimated accretion. Both also show indications of higher rates of mass transfer relative to the expectations from binary evolution driven purely by gravitational radiation, based on existing optical data for Gaia14aae, which show a hotter white dwarf temperature than expected from standard evolutionary models, and X-ray data for SDSS J080449.49+161624.8 which show a luminosity 10−100 times higher than those for other AM CVn at similar orbital periods. The higher mass transfer rates could be driven …

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Automated Tree Mortality Detection Using Ubiquitously Available Public Data, Michael T. Huggins Mar 2024

Automated Tree Mortality Detection Using Ubiquitously Available Public Data, Michael T. Huggins

Master's Theses

Understanding the dynamic interplay between fire severity, topography, and tree mortality, is crucial for predicting future forest dynamics and enhancing resilience against climate change-induced wildfire regimes. This thesis develops a multi-sensor approach for automated estimation of tree mortality, then applies it to examine trends in tree mortality over a six-year period across a fire affected study site in the Trinity River basin in Northern California. The Random Forest model uses publicly available USGS 3D Elevation Program Lidar (3DEP) and NAIP imagery as inputs and is likely to be easily adaptable to other landscapes. The model had a Receiver Operating Characteristic …

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A Study On Ethical Hacking In Cybersecurity Education Within The United States, Jordan Chew Mar 2024

A Study On Ethical Hacking In Cybersecurity Education Within The United States, Jordan Chew

Master's Theses

As the field of computer security continues to grow, it becomes increasingly important to educate the next generation of security professionals. However, much of the current education landscape primarily focuses on teaching defensive skills. Teaching offensive security, otherwise known as ethical hacking, is an important component in the education of all students who hope to contribute to the field of cybersecurity. Doing so requires a careful consideration of what ethical, legal, and practical issues arise from teaching students skills that can be used to cause harm. In this thesis, we first examine the current state of cybersecurity education in the …

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Improving Automatic Transcription Using Natural Language Processing, Anna Kiefer Mar 2024

Improving Automatic Transcription Using Natural Language Processing, Anna Kiefer

Master's Theses

Digital Democracy is a CalMatters and California Polytechnic State University initia-
tive to promote transparency in state government by increasing access to the Califor-
nia legislature. While Digital Democracy is made up of many resources, one founda-
tional step of the project is obtaining accurate, timely transcripts of California Senate
and Assembly hearings. The information extracted from these transcripts provides
crucial data for subsequent steps in the pipeline. In the context of Digital Democracy,
upleveling is when humans verify, correct, and annotate the transcript results after
the legislative hearings have been automatically transcribed. The upleveling process
is done with the …

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Antioxidant Properties Of Kombucha Beverage Infused With Ganoderma Lucidum And Green Tea From Camellia Sinensis (L.) Kuntze With Several Fermentation Times, Rizki Rabeca Elfirta, Pamungkas Rizki Ferdian, Iwan Saskiawan, Tri Hadi Handayani, Kayla Faza Gustafri Mandalika, Rini Riffiani, Kasirah Kasirah, Ukhradiya Magharaniq Safira Purwanto Feb 2024

Antioxidant Properties Of Kombucha Beverage Infused With Ganoderma Lucidum And Green Tea From Camellia Sinensis (L.) Kuntze With Several Fermentation Times, Rizki Rabeca Elfirta, Pamungkas Rizki Ferdian, Iwan Saskiawan, Tri Hadi Handayani, Kayla Faza Gustafri Mandalika, Rini Riffiani, Kasirah Kasirah, Ukhradiya Magharaniq Safira Purwanto

Karbala International Journal of Modern Science

Kombucha is a functional beverage produced through the fermentation of infused tea or Camelia sinensis (L.) Kuntze (CS) by a symbiotic culture of bacteria and yeast. Apparently, the substrate of kombucha can be substituted to enhance its functional properties. Ganoderma lucidum (GL) is a potential substrate reported to have health benefits. This study aims to evaluate antioxidant properties by comparing different formulations and fermentation times. The formulations prepared in the present study varied in the compositions of GL and CS substrates, namely F1 (100% GL), F2 (75% GL: 25% CS), F3 (50% GL: 50% CS), F4 (25% GL: 75% CS), …

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Relocating Lubra Village And Visualizing Himalayan Flood Damages With Remote Sensing, Ronan Wallace, Yungdrung Tsewang Gurung, Ryan Kastner Feb 2024

Relocating Lubra Village And Visualizing Himalayan Flood Damages With Remote Sensing, Ronan Wallace, Yungdrung Tsewang Gurung, Ryan Kastner

Journal of Critical Global Issues

As weather patterns change worldwide, isolated communities impacted by climate change go unnoticed and we need community-driven solutions. In Himalayan Mustang, Nepal, indigenous Lubra Village faces threats of increasing flash flooding. After every flood, residual muddy sediment hardens across the riverbed like concrete, causing the riverbed elevation to rise. As elevation increases, sediment encroaches on Lubra’s agricultural fields and homes, magnifying flood vulnerability. In the last monsoon season alone, the Lubra community witnessed floods swallowing several agricultural fields and damaging two homes. One solution considers relocating the village to a new location entirely. However, relocation poses a challenging task, as …

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Environmental Analysis Of Codfish Production And Consumption In Portugal, Ayla Frost, Joana Almeida, Joana Dionisio, Radu Godina, Cátia Magro Feb 2024

Environmental Analysis Of Codfish Production And Consumption In Portugal, Ayla Frost, Joana Almeida, Joana Dionisio, Radu Godina, Cátia Magro

Journal of Critical Global Issues

Codfish, a typical dish consumed frequently in Portugal, is fished in the cold Northern Atlantic waters far from the Portuguese coast. Thus, regional tensions and the environmental impacts of Portuguese codfish importation and production are significant current issues. The present study uses a life cycle assessment methodology to evaluate the array of environmental impacts of the production of 1 kg of codfish, following a cradle to gate approach. The life cycle inventory was grouped into catch and preprocessing, transit, and curing stages. The data collection of products and processes in each stage was based on scientific peer reviewed documents, technical …

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Germplasm Enhancement Of Annual Forage Legumes Suitable For Use In Cold Highland Environments, H K. Firincioglu, N Karagullu, S Unal, A M. Abd-El Moneim Feb 2024

Germplasm Enhancement Of Annual Forage Legumes Suitable For Use In Cold Highland Environments, H K. Firincioglu, N Karagullu, S Unal, A M. Abd-El Moneim

IGC Proceedings (1997-2023)

The Central Highlands (CH) of Turkey are characterized by cold winters and dry summers. Under these extreme air temperatures, forage crops are still underexploited as a part of crop rotations. Half of the total vetch hectarage in Turkey is in the CH, and farmers still use the local cultivars that have good adaptability but low yield potential. Therefore, with the aim of identifying and improving the annual forage legume species for the cold and dry environment of the CH, research work was carried out during the 1993/94 and 1994/ 95 crop seasons. Initial results showed that Hungarian vetch (Vicia …

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Use Of The Grazing Animal In Forage Breeding, J H. Bouton, C S. Hoveland, R N. Gates Feb 2024

Use Of The Grazing Animal In Forage Breeding, J H. Bouton, C S. Hoveland, R N. Gates

IGC Proceedings (1997-2023)

The objective of these studies was to determine, in the context of a forage breeding program, the effect of cattle grazing on survival of alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.), and tall fescue (Festuca arundinacea Schreb.). Different cultivars of each species were compared in grazed and ungrazed areas. Results consistently demonstrated that grazing reduced plant stands when compared to ungrazed conditions for each species tested. In alfalfa, however, cultivars developed for grazing tolerance showed much better grazing survival. Infection with the fungal endophyte, Acremonium coenophialum Morgan-Jones & Gams, likewise substantially increased grazing survival in …

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Study Of Genotype X Environment Interaction In Alfalfa Forage Yield, S N. Acharya, G C. Kozub, H Najda, A Aasen Feb 2024

Study Of Genotype X Environment Interaction In Alfalfa Forage Yield, S N. Acharya, G C. Kozub, H Najda, A Aasen

IGC Proceedings (1997-2023)

The response of alfalfa (Medicago sativa L.) forage yield to eight Alberta test sites was studied for the 1990 and 1991 production years. Cluster analysis was used to group locations and cultivars. Analyses of variances indicated genotype x environment (location) interaction for the first cut yield, the total yield and the difference between first and second cut yields. The Brooks, Bow Island (irrigation), Bow Island (dryland) and Provost locations always clustered together indicating that three of these four test sites may be eliminated without sacrificing reliability.

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Selection For Self-Fertility And Self-Fertility In Alfalfa As A Tool For Breeding Strategy Assessment, D Rosellini, F Veronesi, F Lorenzetti Feb 2024

Selection For Self-Fertility And Self-Fertility In Alfalfa As A Tool For Breeding Strategy Assessment, D Rosellini, F Veronesi, F Lorenzetti

IGC Proceedings (1997-2023)

Cultivar development in alfalfa relies on heterosis, that has been mainly exploited by intercrossing selected clones from diverse gemplasm sources; an alternative way was proposed, based on developing double cross cultivars obtained by crossing clones selected for self-sterility, propagated by somatic seed. A different breeding strategy was recently emphasized based on population improvement through inbreeding and recurrent selection; in this case, self-sterility would be selected against. If self-sterility is determined by genetic load, the second strategy should be preferred, and selecting for self-fertility may bring about positive correlated responses for forage yield. Divergent selection for self-fertility was applied in a …

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Morphological And Rapd Variations And Regenerants Derived From Cell Suspension Culture Of Pangolagrass, C S. Chen, S M. Wang, Y K. Cheng Feb 2024

Morphological And Rapd Variations And Regenerants Derived From Cell Suspension Culture Of Pangolagrass, C S. Chen, S M. Wang, Y K. Cheng

IGC Proceedings (1997-2023)

Pangolagrass cv. A254, a sterile strain, is one of Taiwan's major forage sources but recently has faced serious disease problems. Tissue culture was expected to generate variations in the breeding program of pangolagrass. The purpose of this study is to examine the somaclonal variation of regenerated plants by means of phenotypic characters survey and RAPD analysis. After long-term suspension culture and EMS mutagenesis, many regenerated plants with morphological variations have been found. Among the regenerants, 10 clones with obviously different characteristics were selected for further studies. Nine of them showed significant differences in morphological trains as compared to A254. By …

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Phylogenetics Of Apomictic Common Dallisgrass (Paspalum Dilatatum), B L. Burson, M A. Hussey Feb 2024

Phylogenetics Of Apomictic Common Dallisgrass (Paspalum Dilatatum), B L. Burson, M A. Hussey

IGC Proceedings (1997-2023)

Common dallisgrass, Paspalum dilatatum Poir., an important warm season forage grass, is an obligate apomict with 50 chromosomes which associate as 20 bivalents and 10 univalents during meiosis. Because efforts to improve the grass have not been successful, a phylogenetic investigation was initiated to identify the progenitors of common dallisgrass in an effort to circumvent the apomictic barrier to improvement. The genomic composition has been determined for four dallisgrass biotypes: yellow-anthered (2n=4x=40) IIJJ; common (2n=5x=50) IIJJX; Uruguayan (2n=6x=60) IIJJXX; and Uruguaiana (2n=6x=60) IIJJXX. While the source of the X genome is unknown, the genes controlling apomixis are on at least …

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Increased Longevity Of Red Clover Through Selection For Persistence And Disease Resistance, R R. Smith Feb 2024

Increased Longevity Of Red Clover Through Selection For Persistence And Disease Resistance, R R. Smith

IGC Proceedings (1997-2023)

Red clover (Trifolium pratense L.), an excellent perennial forage legume, has been considered for many years to be a short-lived, two to three years, forage. Selection for resistance to foliar and root rot diseases and for longevity of stand over the past four decades has improved the persistence of the currently available cultivars. The present studies were conducted to evaluate the progress from selection for longevity and disease resistance. Selection for stand longevity and improved disease resistance has reliably extended the production of red clover into the third and fourth year. Selection for healthy plants in 3- or …

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