Physical Sciences and Mathematics Commons^™

Long-Term Ecological Research Provides Theoretical And Technical Support For Ecological Restoration And High-Quality Development In Agro-Pastoral Ecotone, Wenming Bai, Cunzheng Wei, Longyu Hou, Linghao Li, Xingguo Han, Wenhao Zhang

Bulletin of Chinese Academy of Sciences (Chinese Version)

Since its establishment in 2001, the Duolun Restoration Ecology Station, Institute of Botany, Chinese Academy of Sciences (Duolun Station) has been dedicated to addressing severe grassland degradation and slow economic development in the agro-pastoral ecotone, north of Beijing. A series of systematic studies were conducted on the degraded grassland ecosystem in the agro-pastoral ecotone of Duolun County, Inner Mongolia. The major research findings are summarized as follows. (1) Elucidated that species-specific trait of plant roots, along with the changes in soil properties, are the primary drivers determining how plant and microbial community structure and function respond to anthropogenic disturbances and …

Duolun Restoration Ecology Station, Institute Of Botany, Chinese Academy Of Sciences, Institute Of Botany, Chinese Academy Of Sciences

Bulletin of Chinese Academy of Sciences (Chinese Version)

No abstract provided.

Ecological Barrier Of Coastal Zone In China: Concept, Functions, And Construction Theory, Guangxuan Han, Xiaoli Bi, Xiyong Hou, Xiaoli Zhang, Qianguo Xing, Yuan Li, Haiqing Ma, Ting Wang, Song Qin

Bulletin of Chinese Academy of Sciences (Chinese Version)

The ecological barrier of coastal zone serves as a critical defense line for safeguarding coastal ecological security and sustainable socio-economic development, with multifaceted functions including wave attenuation, shoreline stabilization, and climate regulation. This study systematically elaborates on the concept and essence of ecological barriers of coastal zone, highlighting their core as land-sea continuums that synergistically leverage ecosystem integrity, hydrological connectivity, and biodiversity to provide systemic deliver protective functions. Nevertheless, China’s coastal ecological barrier construction faces four major challenges, namely, (1) theoretical frameworks, often derived from inland models, inadequately represent the complex land-sea interactions and socio-economic drivers; (2) the absence of …

Spatial Resilience Of Coastal Zones From Landscape Pattern Perspective: Connotation, Characteristics, Key Elements, And Pathways For Enhancement, Haixing Meng, Congchun Wang, Shufeng Ye

Bulletin of Chinese Academy of Sciences (Chinese Version)

The coastal zone is a critical ecological barrier at the land–sea interface. Nevertheless, its defensive and regulatory functions have been severely undermined by climate change and intensified human activities, which have caused landscape fragmentation and reduced connectivity. From the perspective of landscape pattern, this study defines the concept of coastal zone spatial resilience and develops a three-dimensional framework of “structure–process–function”, elucidating its attributes of stability, adaptability, recoverability, and dynamic evolution. By coupling ecological spatial resilience theory, the study identifies key landscape elements shaping spatial resilience and proposes an assessment framework consisting of sensitivity, structure, and ecological vitality and services. Building …

Coastal Zone Ecological Barrier Construction: Holistic Governance And Its Promotion Path, Xiurong Huang, Aihua Jiang, Dou Xiaodong Dou

Bulletin of Chinese Academy of Sciences (Chinese Version)

The coastal zone is the frontier of the interaction between sea and land. As a special geographical unit, it has dual values of ecological security and economic development. It has become an important proposition to promote the resilience construction of coastal zone ecological barrier. In response to the current regulatory dilemma of “Kowloon Sea Governance”, structural contradictions in laws and norms, and complex conflicts of related interests, the construction of coastal zone ecological barrier must move from static protection to dynamic governance. In the goal dimension, the shift from “passive defense” to “resilient system construction” should be realized; in the …

Institutional Safeguards And International Experience For Construction Of Coastal Ecological Barrier, Jiayu Bai, Yalei Qing, Shufeng Ye

Bulletin of Chinese Academy of Sciences (Chinese Version)

The coastal zone is a transitional area shaped by the interaction between land and sea, and it holds significant importance for national ecological security as well as economic and social development. Against the backdrop of advancing Chinese modernization, the research on institutional safeguards for the construction of coastal ecological barrier is essential for building a comprehensive framework for ecological conservation from the mountaintop to the ocean, implementing the major projects to protect and restore key ecosystems and the “dual carbon” goals, and promoting ecological civilization and the construction of a Beautiful China. At present, China’s institutional safeguards for coastal ecological …

Three Decades Of Chinese Internet Technology: Social Risks And Prevention Pathways, Zhaokai Yin, Weifu Zhang

Bulletin of Chinese Academy of Sciences (Chinese Version)

With the rapid advancement and application of big data, artificial intelligence, and mobile Internet technologies, network technology has been driving social development, while its negative effects have gradually emerged. Based on a critical perspective and logical reasoning, this study systematically reviews the evolution and characteristic manifestations of social risks in China’s network technology over the past 30 years, revealing multiple hidden dangers it has caused in data governance, capital operation, and political communication. Under the new situation, to prevent and defuse the social risks of network technology, precise measures should be taken from aspects such as value guidance, institutional regulation, …

Green Nudging: Psychology Facilitates Environmental Protection And Climate Policy, Fuming Xu, Anning Liu, Xinjing Li

Bulletin of Chinese Academy of Sciences (Chinese Version)

Environmental pollution, greenhouse gas emissions, and global warming are the major realities threatening all mankind today, urging all countries in the world to take immediate actions to protect the environment, save energy, reduce emissions, and curb global warming. In practice, it is difficult to completely solve these urgent problems by relying only on laws and regulations, administrative orders and other coercive means, as well as incentives such as monetary incentives. Hence, it is necessary to use the results of relevant research in psychology and behavioral sciences to facilitate environmental protection, energy conservation, and climate policy, and to play an important …

Enhancing Education Through Virtual Reality: A Comparative Study Of Vr And Traditional Learning Environments, Shrivardhan Atluri

The Journal of Purdue Undergraduate Research

No abstract provided.

Application Of Reinforcement Learning To Precision Aerial Delivery System Control In Adverse Wind Conditions, Radman Zarbock

The Journal of Purdue Undergraduate Research

Precision aerial delivery systems (PADS) are a subset of airdropped parachute-leveraging package delivery systems that use autonomous guidance, navigation, and control (GNC) to reach targets with high degrees of accuracy. This technology emerged in the 1990s, and strides have been made since to improve the reliability of traditional physics-based controllers that guide PADS. However, these algorithms still struggle to deliver acceptable performance results when PADS are subjected to austere operating environments, such as those with unpredictable wind. Building on a foundational study in 2022 that used artificial intelligence (AI) and machine learning to improve PADS GNC performance, this study aims …

A Cave In Miocene Conglomerate: The Törökpince-Abaliget Cave System, Hungary, Krisztina Sebe, Piroska Pazonyi, Márton Bauer, Bálint Szappanos, Márton Szabó, Zoltán Szentesi, Mihály Gasparik, Ákos Juhász, Luca Pandolfi, Máté Gregorits, József Haász, Ágnes Novothny, Zsófia Ruszkiczay-Rüdiger

International Journal of Speleology

Conglomerate caves are rare, and only a few have been described in the scientific literature. Here, we present a newly discovered and significant cave system in SW Hungary, comprising over 500 m of upper passages and a shorter, lower section of a through-cave developed in Lower–Middle Miocene conglomerates. The formation of these cave passages was controlled chiefly by bedding and fractures. Dissolution has produced typical karstification morphologies, whereas corrasion, granular disintegration, and rock collapse have also played a role in shaping the cave. The cave is dominated by vadose-zone morphologies, but sediment infills indicating upward water flow, along with ceiling …

A Parallel Interval Modeling Framework For Nonlinear Systems: Application To A Modified Duffing Oscillator, Roman Voliansky, Nina Volianska

Northeast Journal of Complex Systems (NEJCS)

The paper presents a mathematical framework for converting nonlinear dynamical systems into parallel forms. This framework replaces the exact system motion equations with interval equations, enabling the representation of nonlinear functions over piecewise linear domains. Such representation enables the description of system motions using linear-like differential equations, which can be analyzed and manipulated using well-known control methods. One such method is eigenvalue analysis, a powerful tool in classical control theory since many techniques rely on the system’s characteristic polynomial and its eigenvalues. We apply this method to define interval system eigenvalues and track their variation during system operation. These eigenvalues …

Structural Framework And Tectonic Implications From Field Investigations In The Ramelau Mountains, Timor-Leste, Tanner A. Nielsen

Theses and Dissertations

Recent advances in petroleum exploration off the southern coast of Timor-Leste and emerging mineral discoveries onshore have underscored the need for a more comprehensive structural understanding of the nation's geology. Although new structural models have been proposed for other parts of Timor, limited progress has been made toward developing detailed models for the Ramelau Mountains, which presents the highest structural relief of the Timor Ranges. Previous mapping in this area has been largely reconnaissance in nature and focused primarily on surface bedrock geology. This study presents a new 1:62,500-scale geologic map and a geometric structural analysis of the Ramelau region …

Amp: Single-Shot Ultra-Wide Fisheye-To-Cubemap Pnp Pose Estimation, Ryan M. Raettig, Richard R. Nyquist, Scott L. Nykl, Clark N. Taylor, Christine M. Schubert Kabban

Faculty Publications

Estimating the position and orientation of a rigid object from an image is critical for situational awareness in robotics and autonomous systems. This study explores relative pose estimation using an ultra-wide fisheye camera for unmanned aircraft inspection vehicles. Ultra-wide fisheye lenses introduce radial distortion and capture features beyond the rectilinear image plane, rendering rectilinear Perspective-n-Point (PnP) algorithms inadequate. Designing a bespoke ultra-wide fisheye localization algorithm requires consideration of both the feature detection method and the pose estimator itself. This study proposes a novel method that combines (1) a fisheye-to-cubemap reprojection, (2) a You Only Look Once (YOLO) convolutional neural network …

Passages: The Discovery Of A Strongly Lensed Protocluster Core Candidate At Cosmic Noon, Nicholas Foo, Kevin C. Harrington, Brenda L. Frye, Patrick S. Kamieneski, Min S. Yun, Massimo Pascale, Ilsang Yoon, Allison Noble, Rogier A. Windhorst, Seth H. Cohen, James Lowenthal, Melanie Kaasinen, Belén Alcalde Pampliega, Daizhong Liu, Olivia Cooper, Carlos Garcia Diaz, Anastasio Diaz-Sanchez, Jose Diego, Nikhil Garuda, Eric F. Jiménez-Andrade, Reagen Leimbach, Amit Vishwas, Q. Daniel Wang, Dazhi Zhou, Adi Zitrin

Astronomy: Faculty Publications

Investigating the processes by which galaxies rapidly build up their stellar mass during the peak of their star formation (z  =  2–3) is crucial to advancing our understanding of the assembly of large-scale structures. We report the discovery of one of the most gas- and dust-rich protocluster core candidates, PJ0846+15 (J0846), from the Planck All-Sky Survey to Analyze Gravitationally lensed Extreme Starbursts (PASSAGES) sample. The exceedingly high total star formation rate (SFR) uncorrected for lensing magnification ( μ) of  μSFR  yr−1 is the result of a foreground cluster lensing at least 11 dusty star-forming galaxies between z …

Discovery Of The Multi-Ion Bridge Intermediate: A Computational Exploration Of The Mechanism For Azomethine Ylide Formation From N-Oxides, Martin J. Neal

Electronic Theses and Dissertations

Density functional theory (DFT) provides a method for calculating the ground-state energies of complex molecular systems through evaluating the electron density instead of the full wave function. When results match either experimental outcomes, calculations with DFT offer a computationally efficient method to help explain chemical phenomena. The transformation of tertiary amine N-oxides to azomethine ylides, a simple route to the precursor for 1,3-dipolar cycloadditions that result in the pyrrolidine scaffolds found in natural products, has received only minimal attention due to concerns that its mechanism includes a highly electrophilic intermediate. Utilizing DFT to model the mechanism of the conversion …

The Johnson-Křížek-Mercier Elasticity Element In Higher Dimensions, Jay Gopalakrishnan, Johnny Guzman, Jeonghun J. Lee

Mathematics and Statistics Faculty Publications and Presentations

Mixed methods for linear elasticity with strongly symmetric stresses of lowest order are studied in this paper. On each simplex, the stress space has piecewise linear components with respect to its Alfeld split (which connects the vertices to barycenter), generalizing the Johnson–Mercier two-dimensional element to higher dimensions. Further reductions in the stress space in the three-dimensional case (to 24 degrees of freedom per tetrahedron) are possible when the displacement space is reduced to local rigid displacements. Proofs of optimal error estimates of numerical solutions and improved error estimates via postprocessing and the duality argument are presented.

Assessment Of Polymeric Chloroquine Formulations For Targeted Therapy Of Ulcerative Colitis And Metastatic Colorectal Cancer, Neha Kumari

Theses & Dissertations

Effective targeted drug delivery is a critical unmet need in the management of both ulcerative colitis and metastatic colorectal cancer, where conventional systemic therapies may be hindered by suboptimal efficacy and significant side effects. This thesis explores the development and preclinical assessment of polymeric chloroquine (PCQ)-based nanotherapeutics, leveraging stimuli-responsive designs for disease-specific delivery and action.

For ulcerative colitis, a reactive oxygen species (ROS)-responsive nanogel system was engineered to release PCQ, a macromolecular derivative of hydroxychloroquine, specifically in the inflamed areas within the colon. Nanogels with well-defined size and positive surface charge were synthesized via reversible fragmentation chain transfer (RAFT) polymerization …

Nontoxic Paints Using Cornstarch As Binders, Maile Prater

Honors Projects

For this project, paints were created using different metal compounds which interacted with cornstarch and pectin to determine whether the metals would coordinate with these polysaccharides to create new types of watercolor paints. The paints that were created were ran through an RGB analysis to determine how much of each RGB color is present in a solution and then were ran through a rheometer to determine how the viscosity differed between each solution.

Quasiparticle Weight And Effective Mass Of The Landau Liquid From The Complex-Frequency Formalism, Aydin Cem Keser, Oleg P. Sushkov

Turkish Journal of Physics

We present a method for calculating the effective mass and quasiparticle weight of a Landau Fermi liquid using time-ordered Green’s functions and a Wick rotation to the imaginary frequency axis. This technique simplifies the evaluation of self-energy derivatives by ensuring analytic properties compatible with contour deformations. We apply the method to the electron gas in both two and three spatial dimensions within the random phase approximation (RPA), and derive explicit expressions for the static and dynamic contributions to the self-energy. Our results confirm known limits at weak coupling and offer an accurate and transparent route to evaluate effective mass and …

Application Of Polarization Transfer Algorithm In Organic Molecules With Three Nonequivalent Coupled Spins, Dim Safin, Alexander Perepukhov, Sergei Rzhevskiy, Yuri Belousov

Turkish Journal of Physics

Polarization transfer between three $1/2$ nuclear spins in a specially prepared isotopically enriched molecule diethylphthalimide malonate-2-$^{13}$C,$^{15}$N molecule was obtained using the nuclear magnetic resonance (NMR) method. The polarization transfer was performed by implementing a sequence of radio frequency pulses and waiting intervals. Relaxation times and NMR spectrum for the studied nuclei were measured in samples of molecules with natural and enriched isotopes $^{13}$C and $^{15}$N. Measurements of the proton relaxation rate for diethylphthalimidomalonate and diethylpthalimidomalonate-2-$^{13}$C,$^{15}$N showed an increase in relaxation rate by a factor of 4 for protons bound to $^{13}$C,$^{15}$N nuclei. The use of the quantum polarization transfer method …

First-Principles And Deep Learning Frameworks To Predict The Electronic, Magnetic And Electrical Properties Of V-Doped Sic Nanotube, Debarati Dey Roy, Sevda Rzayeva, Sevinj Guluzade, Vusala Nabi Jafarova

Turkish Journal of Physics

Nowadays, with the miniaturization of nanoindustry, we are increasingly interested in doping effects for nanotube systems. In this study, based on density functional theory (DFT) and local spin density approximation (LDA) methods within Hubbard U corrections, the electronic, magnetic and electrical properties of single-wall silicon carbide nanotubes doped with vanadium were theoretically studied. Although the undoped SiC system is nonmagnetic, the V-doped SiC nanotube induces magnetism and the total magnetic moment of this magnetic material is equal to ~1 µB. Density of states calculations indicated that the magnetization of SiC:V single-wall nanotubes mainly comes from the 2p orbitals of carbon …

Corrigendum To “Circular Motion And Thermodynamic Characteristics Of Particles Around A Quintessential Nonrotating Black Hole” [Turkish Journal Of Physcis 49 (3) 2025 72-91], Indrajit Halder, Kamal Lochan Mahanta, Rakesh Ranjan Sahoo

Turkish Journal of Physics

This corrigendum addresses an error in equation (35) in the original published version of this article. This error led to minor inaccuracies in subsequent equations.To correct this oversight and ensure the accuracy of the scholarly record, the corrected equations are provided below for reference. The authors apologize for any inconvenience caused and state that the scientific conclusions are unaffected. Corrected equations ofsection 3.3. [2,3]:

The original article can be accessed at: https://doi.org/10.55730/1300-0101.2777

Macroinvertebrate Community Dynamics In A Recovering, Hypersaline Estuary, Catherine M. Eckert, Claudia A. Tamez, Erin E. Easton, David Hicks

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Bahia Grande is a 6,500—acre tidal basin located at the southernmost tip of Texas. Tidal flow into this coastal estuary was cut off in the 1930s, causing the basin to dry up for ~70 y. A pilot channel connecting the Bahia Grande to tidal waters was constructed in 2005, allowing flooding of the basin to occur. Throughout the period reported herein (2005–2019), the system remained characterized by persistent spatial and temporal episodes of extreme hypersalinity (>70)—a critical factor influencing estuarine community composition and driving key ecological processes. With additional rehabilitation actions forthcoming, characterization of the estuary is essential …

Perron Theorem Application To A Second-Order Differential Equation With Small Advances, Jason Hendrix

Theses and Dissertations

We analyze a delayed second order differential equation with small delay parameters, proving spectral stability via the characteristic quasi-polynomial and establishing uniform bounds on derivatives of the Green’s function to ensure sign preservation under perturbation, providing a foundation for monotone iteration methods. These results aim to advance the functional-analytic framework for traveling wave solutions in delayed reaction-diffusion systems.

Self-Assembling Rna Nanostructures Are Highly Sensitive To Environmental Conditions, Jordan Aposhian, Surya Pratap S. Deopa, Scott Horowitz, Joseph D. Yesselman

Chemistry and Biochemistry: Faculty Scholarship

Recent developments in RNA nanotechnology have led to an increase in the design of specific, higher-order RNA structures, which will ultimately be used in drug delivery and immunomodulation applications. As researchers create RNA nanostructures with the intention of making them a standard tool in molecular biologists' toolkits, further investigation is required into the robustness of RNA designs. Primarily, in what different molecular contexts are the designed and intended nanostructures stable? In this work, we show that RNA nanostructure self-assembly is highly sensitive to environmental conditions by using second-order right-angle light scattering. While a test RNA hexagonal grid nanostructure forms correctly …

Gowanus Faces A Hidden Threat Beneath Its Neighborhood Boom, Emma J. Rosenberg

Capstones

This article investigates urban redevelopment, climate change and environmental contamination in Brooklyn’s Gowanus neighborhood. The Gowanus Canal itself has been a designated EPA Federal Superfund Site since 2010, this designation does not apply to the land surrounding it where legacy industrial contamination still exists. This includes coal tar from former manufactured gas plants which poses a risk to groundwater and indoor air. Under a 2021 rezoning plan, large-scale residential redevelopment is rapidly moving forward, rising groundwater and increased flooding associated with climate change may exacerbate contaminants. Utilizing agency documents, Community Advisory Group meetings, and conversations with residents, advocates, officials and …

How Has Your Climate Changed?, Rhyannon Bartlett-Imadegawa

Capstones

This interactive data visualization shows readers how much the climate has changed in their home state compared to 100 years ago, since the reader was born, the current year and projections into the future. It aims to communicate climate change impacts more personally by linking it to seasons, the reader's birth year and age mile stones and compares a readers' home state to a state that has been more impacted to connect across different states and communities.

Using JavaScript and Svelte, the code calculates and displays seasonal averages for the baseline period for the reader's state and years for the …

Flooding, Not Just A Rain Problem, Annisha Singh

Capstones

This capstone focuses on the Rockaway Peninsula and how high-tide flooding also known as "sunny-day flooding" is not only affecting Rockaway but neighboring areas, such as Jamaica Bay.

Black Women And Latinas In Stem: A Systematic Review Of Literature, Karin Moore

The Scholarship Without Borders Journal

This systematic review of literature examines scholarly studies conducted on Black women and Latinas in STEM fields and in STEM higher education. Women are underrepresented in STEM, and on average they comprise 27% of the STEM population (National Science Foundation, 2017). Black women and Latinas are even further underrepresented in STEM by making up only 14.58 % and 3% of the employees in STEM industries (Hispanic Heritage Foundation, 2020; National Science Foundation, 2021). Barriers for all women are the focus of much of the body of literature in STEM (Beach et al., 2024; Moore, 2024). Isolating specific challenges Black women …