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Estimation of Evapotranspiration Using Remote Sensing Data and Sebal Model in Adana, Turkiye
No full textThe world's population has been steadily increasing in recent decades, resulting in a higher demand for water. This demand, combined with the effects of climate change and the depletion of natural resources, has made it crucial to monitor water resources. Agriculture is the largest user of water, and its impact on water usage is becoming a growing concern. Evapotranspiration, which is the combined loss of water through evaporation and plant transpiration, plays a crucial role in the water budget and energy balance. This study examined the use of the python SEBAL (PySEBAL) model for estimating evapotranspiration in agricultural areas by utilizing Landsat satellite imagery and meteorological data. The research centered on Seyhan Plain, Adana, Turkey, from 2017 to 2019 and analyzed both summer and winter seasons across five different crop types: cotton, wheat, corn, soybean, and citrus. The PySEBAL model generated daily actual evapotranspiration maps at 30m resolution for the study area. Analysis of R-square values across years and crops revealed positive correlations, particularly for cotton (R-square = 0.819) and wheat (R-square = 0.809). Corn and citrus also showed positive correlations (R-square = 0.736 and 0.708, respectively), while soybean2 displayed a weaker association (R-square = 0.481). These findings suggest that the PySEBAL model can accurately predict Penman-Monteith evapotranspiration (PM-ET) for some crops (cotton, wheat) compared to others (soybean-2). The results indicated an overestimation of ET by the model compared to literature values. However, a positive correlation was found between PySEBAL-ET and Penman-Monteith evapotranspiration (PM-ET) estimates across all crops and years, suggesting the potential of SEBAL for agricultural water resource monitoring
Enhancing the Nutritional Quality of Red Leaf Lettuce by Optimizing End-of-Production Supplemental LED Lighting
No full textRed leaf lettuces (Lactuca sativa) are commercially significant leafy vegetables grown both in open fields and controlled-environment facilities such as greenhouses and indoor farms. These plants produce anthocyanins, a group of secondary metabolites that enhance their red coloration and nutritional value. However, low light levels in controlled environments can reduce the biosynthesis of anthocyanins and other key phytochemicals such as phenolics, ascorbic acid, and carotenoids. The light conditions in controlled environments could be optimized by leveraging the light-emitting diodes (LED) technology, potentially improving phytochemical accumulation. This research had two primary objectives: 1) to assess whether a higher intensity, shorter duration blue light would increase anthocyanin production more than a lower intensity, longer duration blue light, given the same total cumulative amount of supplemental blue light applied at the end of production (EOP), and 2) to compare the effectiveness of different light spectra, including red, blue, violet, ultraviolet-A (UVA), and ultraviolet-B (UVB), on enhancing anthocyanins and total phenolics in red lettuce during EOP. Our results indicated that a medium intensity of blue light applied over a medium duration resulted in the highest anthocyanin levels when the same amount of supplemental blue light was applied at varying intensities and durations. In evaluating various monochromatic light treatments, we found that supplemental violet light resulted in the highest leaf expansion and biomass, while UVB radiation (3 ��mol m^- �� s^-1 ), despite its lower intensity compared to other light spectra (60 ��mol m^- �� s^-1 ), was most effective at enhancing the accumulation of phytonutrients such as anthocyanins and phenolics but caused yield reductions. We caution that the tradeoff between enhanced crop nutritional quality and reduced crop yield must be carefully considered in commercial applications
A Primate Model for Studying the Importance of Environment and Family Lineage on Development, Health, and Aging
No full textThe Cayo Santiago rhesus macaques are one of the most intensely studied primate colonies in the world. They are associated with a rare skeletal collection that is contextualized with known sex, age, and familial information. The purpose of this dissertation is to elucidate environmental and genetic contributions of bone health, evolution, and development. In doing so, this will become a translational resource for human disease and variation. This study departs from previous endeavors by extracting almost all development and pathological data from the derived skeletal collection and stratifying it with known life-history and demographic information to produce reliable biomedical models of health. The backbone of the proposed model is derived from the skeletal collections housed at the Caribbean Primate Research Center University of Puerto Rico, Medical Sciences Campus and New York University, Department of Anthropology. Statistical analysis such as relative risk ratios, and multivariate regression were employed to test for the relative roles of environment and genetics on bone health in the population. The Cayo Santiago population were found to exhibit secular trends in congruence with ecogeographic rules. Specifically, body weights declined, and limb dimensions became slenderer, increasing surface area/volume ratios of individuals and heightening heat expenditure in a more homogeneously warm climate than the one they were adapted to over evolutionary timescales. In contrast to the gradual impacts of climate, major hurricane events precipitated increased levels of systemic disease, bone mineral density (BMD) reductions, and delayed dental eruption timings. Greater rheumatic disease, lower BMD, and delayed dental eruption are believed to relate to immune dysregulation, low grade chronic inflammation, and early-adversity. Further analysis indicated that disease is also patterned across families indicating that a genetic susceptibility to disease can be observed within the matrilines of the Cayo population. Lastly, the neurosurgical landmark, the pterion, exhibited strong support for inheritance of pattern. This work suggests craniotomies using the pterional approach may benefit from taking or making use of family history of pterion type and subsequently benefit from aspects of its variatio
Characterization of Ligand Binding Using Dissolution DNP Assisted NMR Spectroscopy
No full textBiomolecular interactions play essential roles in cellular processes including signaling, metabolism, and enzymatic synthesis of cellular components. Elucidating interactions between proteins and ligands using techniques such as nuclear magnetic resonance (NMR) spectroscopy provides fundamental insights into biological function, as well as guidance on the identification of new drug candidates. A significant NMR sensitivity improvement of several thousand-fold can be achieved by hyperpolarizing the ligand molecule using dissolution dynamic nuclear polarization (D-DNP). Spectra can be acquired in a reduced time, at or near physiological concentrations. Here, transverse (R2) NMR relaxometry is demonstrated to probe protein-ligand interactions. A 13C R2 relaxation dispersion measurement characterizes ligand binding epitopes through the observation of relaxation rates at different positions of the ligand, whereby the magnitude of the dispersion reflects the binding orientation of the ligand. The efficiency of the R2 measurement can be improved by an ultrafast approach to obtain the relaxation rates from all 13C spins in a single measurement. Numerous target proteins for pharmaceuticals are embedded in the cell membrane. Hyperpolarized 19F, due to its low NMR detection limit, is proposed for probing the interactions with membranes and the cell surface proteins. A model for the binding interaction combined with predictions of spin relaxation rates provides estimates of the binding affinity to membranes of different compositions in unilamellar vesicles. Applied to the measurement of ligand interactions with different cell types, the influence of the interactions between ligands and cell membrane proteins is identified
Exploration of New Passive and Active Attacks and Defense Methods for the KLJN and the VMG-KLJN Secure Key Exchangers
No full textThe Kirchhoff-Law-Johnson-Noise (KLJN) scheme is an unconditionally secure (information-theoretic) key exchanger based on the laws of classical statistical physics. The unconditional security of the KLJN scheme is provided by the Second Law of Thermodynamics, which requires thermal equilibrium (homogeneous temperature) for the system with zero flow. The KLJN scheme's foundational security principle was challenged by Vadai, Mingesz, and Gingl (VMG) through their VMG-KLJN system, which operates under inhomogeneous temperature and nonzero power flow conditions, while claiming equivalent security. Through our research, by applying various passive and active attacks against both schemes, we prove ideal KLJN scheme offers superior security over the VMG-KLJN scheme and reaffirm that thermal equilibrium remains the foundation of security. However, the VMG-KLJN method can, with appropriate countermeasures, be sufficiently secure for practical situations.
Our first study reveals that under practical conditions with nonzero cable capacitance and inductance, the VMG-KLJN scheme is vulnerable to certain passive attacks (crossover frequency attack and noise temperature attack), while the original KLJN scheme remains resistant against such attacks. In other words, the VMG-KLJN system is less secure than the original KLJN system. We also show that some of these vulnerabilities can be fixed by yet another new protocol that we introduce here. However at least one of these vulnerabilities will always remain. Thus, the information leak is never mathematically zero.
In our second study, the vulnerability of the VMG-KLJN key exchanger against two active attacks (current injection and voltage insertion attacks) is exposed. The security vulnerability arises from the fact that the effective driving impedances are different between the HL and LH cases for the VMG-KLJN scheme, whereas for the ideal KLJN scheme, they are the same. Two defense schemes are demonstrated, each effective against only one type of attack, but not against the two attacks simultaneously. The theoretical results are confirmed by computer simulations.
In the latter part of the dissertation, we demonstrate the security vulnerability of the ideal KLJN key exchanger and the VMG-KLJN key exchanger, respectively, against transient attacks. Transients start when Alice and Bob (two communicating parties) connect the wire to their chosen resistor at the beginning of each clock cycle. A transient attack occurs during a short duration of time, before the transients reflected from the ends of Alice and Bob mix together. The information leak arises from the fact that Eve (eavesdropper) monitors the cable and analyzes the transients during this time period. We demonstrate such a transient attack, and, then we introduce a defense protocol to protect against the attack. Computer simulations demonstrate that after applying the defense method the information leak becomes negligible
Geomicrobiology of Seafloor Basalts and Viral Metagenomes of Seafloor Habitats in the Pacific Ocean
No full textSeafloor basalts, inactive sulfides, and seamounts represent broadly distributed biospheres on the seafloor. Here, the microbial community composition, functional potential, and extracellular enzyme activity rates were assessed within these seafloor habitats, with an emphasis on seafloor basalt samples. Extracellular enzyme activity assays were performed using seafloor basalt from the East Pacific Rise (EPR) 9��50'N and Davidson Seamount, to understand their role in carbon, nitrogen, and phosphorus acquisition. Metagenomics was also used to evaluate the differences in the microbial community composition and functional potential of seafloor basalts from two different age groups represented by two separate eruptions at EPR 9��50'N. Viruses from metagenomes of seafloor basalts, inactive sulfides, and ferromanganese crust from the EPR 9��50'N, Southern Mariana Trough, PACManus, and Takuyo-Daigo Seamount were also analyzed to characterize the overall viral community composition, auxiliary metabolic gene function, and virus-host linkages. The analyses conducted here offer an insightful understanding of the resident microbial community within seafloor habitats, shedding light on their nutrient acquisition mechanisms via extracellular enzyme activity, and their genetic potential to uptake and utilize nutrients in their environment. In addition, these analyses explore the previously overlooked role of viruses in the survival of the prokaryotic community present. The abundance and importance of these seafloor habitats in the ocean emphasizes the need to understand the ecology of the resident microbial life, and their potentially significant role in marine nutrient cycling
Linking Cardiovascular and Neuromotor Responses to an Orthostatic Challenge
No full textHuman physiology has adapted few responses to changes in the orthostatic gradient typically caused by gravity and postural changes. Sustained alterations to our gravitational environment, whether through bedrest or during human spaceflight missions, are known to elicit multi-system physiological decrements. Previous work has identified potential differences in the responses of males and females.
The current work delivered an acute bout of orthostatic stress to 24 sex-balanced subjects via step-wise increases in lower-body negative pressure (LBNP) levels. During this intervention, subjects performed one of four bimanual coordination tasks. Measures of systemic hemodynamics, autonomic indices, and bimanual coordination task performance were performed. Orthostatic dose-response curves were generated, and a correlation analysis between the metrics of the two systems was performed. Additionally, statistical models were selected that best predict tolerance to the orthostatic challenge using baseline cardiovascular metrics. Models using cardiovascular metrics to best predict task performance were also selected.
The orthostatic challenge was successful in eliciting early and robust cardiovascular responses, especially in metrics related to sympathetic drive. Neuromotor performance changes to the orthostatic challenge, where they occurred, were usually only detectable in the final levels of the LBNP intervention. The most consistent neuromotor responses were increases in the pace of motor inputs, and increases in the variability of forces applied. Baseline cardiovascular health metrics were the best predictors of tolerance. Time-domain autonomic indices of heart rate variability were shown to be the strongest predictors of the increases in the pace of motor inputs. No differences were detected between male and female Index of Tolerance scores.
These results inform our understanding of cardiovascular and neuromotor responses to an orthostatic challenge both in a dose-response manner and an integrative manner. They suggest that neuromotor decrements may occur at the point during an orthostatic challenge at which sympathetic drive becomes the dominant factor in further cardiovascular responses. Data also suggest that sex differences in orthostatic tolerance may not be the result of anatomical and anthropometric differences. Finally, it is proposed that the discovered linkages between the two studied systems may reside in the insula, a structure deep in the brain with functions in both systems
Improving the Sensitivity of the Search for New Resonances in the X->HH->bbWW Channel at the LHC with the CMS Detector
No full textThe Standard Model (SM) of particle physics successfully describes fundamental particles and three out of four fundamental interactions. However, it fails to incorporate the fourth fundamental interaction, gravity, and cannot explain observed phenomena like matter-antimatter asymmetry. These limitations suggest new physics beyond the SM, possibly probed via Higgs boson pair (HH) production at the CERN Large Hadron Collider (LHC). This dissertation presents the results of a search for new heavy resonances (denoted as ���X���) with spin-0 and spin-2 decaying into HH at the LHC in the bbW+W��� channel, specifically: X ��� HH ��� bbW+W��� ��� bbl+��l�����. It uses 137.6 fb���1 proton���proton collision data at a center-of-mass energy of 13 TeV recorded by the Compact Muon Solenoid (CMS) detector from 2016 to 2018. The presence of two escaping neutrinos in the final state leads to an unconstrained kinematic system, making direct reconstruction of the heavy resonance mass impossible. To address this challenge, the search employs a new technique, called the Heavy Mass Estimator (HME), which estimates the heavy resonance mass in a probabilistic approach. Additionally, compared to an earlier CMS search using only 2016 data, this search extends event selection criteria to enhance signal acceptance and adopts an advanced machine learning architecture. These two enhancements alongside the HME technique significantly increase sensitivity, achieving 2 to 5 times greater sensitivity compared to the 2016 search, assuming the same amount of data. No statistically significant evidence for new heavy resonances is found within the data. Upper limits at a 95% confidence level are set on the production cross sections of new resonances decaying into HH. These limits vary from 7.149 pb to 0.030 pb for spin-0 resonances and from 5.569 pb to 0.023 pb for spin-2 resonances, in the mass range from 250 GeV to 900 GeV
Mechanisms of Circadian Clock Control of Rhythmic Translation in Neurospora crassa
No full textThe circadian clock in Neurospora crassa regulates daily rhythms in the phosphorylation and daytime inactivation of the conserved translation initiation factor eIF2��. Clock control of eIF2�� activity is responsible for the rhythmic translation of ~15% of mRNAs. Cycling phosphorylated eIF2�� levels require rhythmic activation of the eIF2�� kinase CPC-3 (the homolog of yeast and mammalian GCN2). However, how the clock controls the activity of CPC-3 is not known, and this information is critical to determine the mechanisms underlying rhythmic protein synthesis. To be activated, CPC-3 forms a complex with GCN1, which helps to bring uncharged tRNAs to the tRNA binding domain on CPC-3. In Saccharomyces cerevisiae, activation of GCN2 under stress conditions requires direct interaction of GCN1 and GCN2 with ribosomes. Furthermore, CPC-3 and GCN1 levels are clock-controlled in N. crassa. Based on these data, I hypothesized that N. crassa CPC-3 and GCN1 rhythmically interact with the ribosome, and that this interaction is necessary for rhythmic CPC-3 activity and eIF2��-controlled translation initiation. To test this hypothesis, the interaction of CPC-3 and GCN1 with ribosomes was examined in WT and the clock mutant ��frq. Ribosomes were pelleted from cultures grown in constant dark (DD) and harvested every 4 hours in a circadian time course. I found that CPC-3 and GCN1 interact with monosomes and polysomes, and that the interaction is clock-regulated with peak levels during the subjective day. We showed previously that rhythms in uncharged tRNA levels, and rhythms in CPC-3 activity are abolished in a valyl tRNA synthetase temperature sensitive mutant (un-3ts). The rhythmic interaction of CPC-3 and GCN1 with ribosomes was abolished in the un-3ts mutant, suggesting that rhythmic levels of uncharged tRNA drives the rhythmic interaction of CPC-3 and GCN1 with ribosomes. I found that disrupting the interaction between GCN1 and uncharged tRNA in the absence of GCN20, affects rhythmic CPC-3 activity. Taken together, these data support that clock regulation of rhythms in uncharged tRNA levels and rhythms in the interaction between CPC-3 and GCN1 with ribosomes are necessary for rhythmic CPC-3 activity that leads to rhythms in the translation of target mRNAs
A Massively Parallelizable Surrogate-Based Modeling Framework for Nonlinear Static Aeroelasticity and Structural Design
No full textAnalyzing the multiphysical coupling between a deformable structural body and the forces
imposed on that body from a surrounding fluid can be a challenging and computationally expensive
task, especially when the structure and/or fluid exhibit highly nonlinear behavior. Consequently,
preliminary design of aerostructures often relies upon simplified mathematical models
limited to linear fluid and structural regimes to enable tractable exploration within a design space
predominantly defined by convention and engineering expertise. While this has historically proven
reliable, such design practices are inadequate for developing next-generation aerial systems requiring novel structural solutions for in situ geometric reconfigurations that enable continuous
optimization of aerodynamic performance, enhanced control authority, and expansion of operational
capacity. Accordingly, there exists a need for novel reduced-order multidisciplinary analysis
techniques agnostic to the underlying complexities of the physical problem that make efficient
use of high-fidelity computational models to resolve the exchange of field information between
disparate physics subdomains. This work explores a highly parallelizable non-intrusive reduced-order
modeling technique that seeks to construct an aeroelastic surrogate model approximating the
function composition of the high-fidelity structural model and fluid model in terms of shape parameters characterizing a reduced geometric description of the deformed interface boundary between physics domains. The proposed methodology removes the need for a reduced-order representation of the traction field acting on the structure, eliminates computationally expensive fluid evaluations during structural design procedures, and requires no explicit communication between independent fluid and structural models. Furthermore, while this data-driven modeling approach is highly enabling for parametric multi-objective structural design optimization during preliminary design
stages, identifying structural design variables requires foreknowledge of the structural topology.
This work applies many of the same principles to develop a novel reduced-order aeroelastic topology
optimization framework that supplements conceptual design stages with knowledge of the static aeroelastic response while considering nonlinear aerodynamics