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Temperature Forecasts for the Continental United States: A Deep Learning Approach Using Multidimensional Features
Get PDFAccurate weather forecasts are critical for saving lives, emergency services, and future developments. Climate models such as numerical weather prediction models have made significant advancements in weather forecasts, but these models are computationally expensive and can be subject to inaccurate representations of complex natural interconnections. Alternatively, data-driven machine learning methods have provided new dimensions in assisting weather forecasts. In this study, we used convolutional neural networks (CNN) to assess how geopotential height at different levels of the troposphere may affect the predictability of extreme surface temperature (t2m) via two cases. Specifically, we analyzed temperature forecasts over the continental United States at lead times from 1 day to 30 days by incorporating z100, z200, z500, z700, and z925 hPa levels as inputs to the CNN. In the first case, we applied the framework to predict summer temperatures of 2012, which contributed to one of the extreme heatwave events in the U.S. history. The results show that z500 leads to t2m forecasts with relatively less root mean squared errors (RMSE) than other geopotential heights at most of the lead time under consideration, while the inclusion of more atmospheric pressure levels improves t2m forecasts to a limited extent. At the same lead time, we also predicted the z500 patterns with different levels of geopotential height and temperature as the inputs. We found that the combination of z500, t2m, and t850 (temperature at 850 hPa) is associated with less RMSE for the z500 forecasts compared to other inputs. In contrast to the 2012 summer, our second case examined the wintertime temperature of 2014 when the upper Midwest and Great Lakes regions experienced the coldest winter on record. We found that z200 contributes to better t2m predictions for up to 7-days lead times whereas z925 gives better results for z500 forecasts during this cold event. Collectively, the results suggest that for long-range temperature forecasts based on the CNN, including various levels of geopotential heights could be beneficial
Effect of Strain Profiling on Anisotropic Opto-Electronic Properties of As\u3csub\u3e2\u3c/sub\u3eX\u3csub\u3e3\u3c/sub\u3e (X =S, Te) Monolayers from First Principles
Get PDFStrain Engineering is a widely adopted approach to modulate the opto-electronic performance of 2-Dimensional (2D) materials. Recently, anisotropic Van der Waals (vdW) based 2D As2S3 monolayer has gained significant attention within the scientific community due to its stability in ambient conditions. Similar compounds like As2Te3 have also been theoretically explored. However, its indirect bandgap nature limits its application in optical devices. In this study, a systematic study of compressive and tensile strain on three profiles–Uniaxial along a-axis, Uniaxial along b-axis and biaxial strain from −10% to +10%, is performed for As2S3 and As2Te3 monolayers. Certain strain profiles like Uniaxial tensile strain of 8% along b-axis results in transition to direct bandgap material. Similarly, for As2Te3, shear strain of (−10%, +8%) along (a, b) axis results in direct bandgap material. In addition, the anisotropic optical absorption spectrum is obtained for unstrained and strained monolayers within the random phase approximation (RPA)
Novel 4th-generation Phytase Improves Broiler Growth Performance and Reduces Woody Breast Severity Through Modulation of Muscle Glucose Uptake and Metabolism
Get PDFThe objective of the present study was to determine the effect of a novel (4th generation) phytase supplementation as well as its mode of action on growth, meat quality, and incidence of muscle myopathies. One-day old male broilers (n = 720) were weighed and randomly allocated to 30 floor pens (24 birds/pen) with 10 replicate pens per treatment. Three diets were fed from hatch to 56- days-old: a 3-phase corn-soy based diet as a positive control (PC); a negative control (NC) formulated to be isocaloric and isonitrogenous to the PC and with a reduction in Ca and available P, respectively; and the NC supplemented with 2,000 phytase units per kg of diet (NC + P). At the conclusion of the experiment, birds fed with NC + P diet were significantly heavier and had 2.1- and 4.2-points better feed conversion ratio (FCR) compared to birds offered NC and PC diets, respectively. Processing data showed that phytase supplementation increased live weight, hot carcass without giblets, wings, tender, and skin-on drum and thigh compared to both NC and PC diets. Macroscopic scoring showed that birds fed the NC + P diet had lower woody breast (WB) severity compared to those fed the PC and NC diets, however there was no effect on white striping (WS) incidence and meat quality parameters (pH, drip loss, meat color). To delineate its mode of action, iSTAT showed that blood glucose concentrations were significantly lower in birds fed NC + P diet compared to those offered PC and NC diets, suggesting a better glucose uptake. In support, molecular analyses demonstrated that the breast muscle expression (mRNA and protein) of glucose transporter 1 (GLUT1) and glucokinase (GK) was significantly upregulated in birds fed NC + P diet compared to those fed the NC and PC diets. The expression of mitochondrial ATP synthase F0 subunit 8 (MT-ATP8) was significantly upregulated in NC + P compared to other groups, indicating intracellular ATP abundance for anabolic pathways. This was confirmed by the reduced level of phosphorylated-AMP-activated protein kinase (AMPKα1/2) at Thr172 site, upregulation of glycogen synthase (GYS1) gene and activation of mechanistic target of rapamycin and ribosomal protein S6 kinase (mTOR-P70S6K) pathway. In conclusion, this is the first report showing that in-feed supplementation of the novel phytase improves growth performance and reduces WB severity in broilers potentially through enhancement of glucose uptake, glycolysis, and intracellular ATP production, which used for muscle glycogenesis and protein synthesis
A Review of Herpetofaunal Distributions in Arkansas with Special Emphasis on Contributions from Citizen Science: Part I – Snakes
Get PDFWe present a comprehensive updated review of the distributions of the 38 species of snakes in Arkansas. We compare historical and current distributions with citizen science data uploaded and verified in iNaturalist, a leading biodiversity monitoring online citizen science database. The Arkansas Herpetological Atlas, a website maintaining species occurrence records, is also used and compared. We highlight the role played by iNaturalist in enhancing our knowledge of snake distributions in Arkansas. 10,885 verified and vetted Research Grade (RG) observations of Arkansas snakes have been recorded in iNaturalist, expanding the known distributions of 36 of the 38 species. This is the first paper in a planned series documenting the current distribution of all herpetofaunal species in Arkansas
A Review of the Interaction Between Potassium Nutrition and Plant Disease Control
Get PDFPotassium (K) is an essential macronutrient involved in many physiological and biochemical functions that affect a plant\u27s susceptibility to disease. These processes include stomatal regulation, enzyme activation, and solute transport, each of which is often discussed through the lens of either plant nutrition or plant disease control. However, the interaction between these stresses and the resulting physiological and agronomic impact is an important consideration when managing a cropping system as a whole and is scarcely addressed in the literature. Therefore, a review of the literature was focused on the interaction of K nutrition and the resulting impact on plant disease control. Nutrient management, especially K, can manipulate these essential plant processes to provide the host plant with either an advantage or disadvantage in disease susceptibility, depending on the pathogen and the situation. Numerous studies have been conducted investigating the individual pathogen and host relationships, concluding that the majority of bacterial and fungal diseases decreased with increasing K nutrition, while viral diseases and nematode infections had inconsistent responses to K nutrition. These differences in the response of disease to K nutrition complicate generalizations across species and environments. Similarly, the impact of K on plant growth is affected by the concentration of each nutrient and its ratio with other nutrients. Therefore, a review of the major physiological processes that depend on plant K nutrition is discussed below with the resulting impact on plant disease control
Rice Sucrose Non-fermenting Related Protein Kinase (SnRK1) Has a Limited Role in Defense Against Fall Armyworm (\u3ci\u3eSpodoptera frugiperda\u3c/i\u3e)
Get PDFSucrose non-fermenting (SNF) related protein kinase 1 (SnRK1) is a master regulator of energy deprivation signaling, has also been implicated in abiotic and biotic stress regulation. SnRK1 promotes stress tolerance through metabolic and transcriptional changes and plays important roles in innate immunity against various pathogens. However, whether it plays a role against insect herbivory is not understood. To test this, using the wild type (with SnRK1) and snrk1 mutant lines in rice, we examined the potential role of SnRK1 in rice against the ruinous pest, Fall armyworm (FAW), Spodoptera frugiperda. We also investigated the response of FAW towards these lines at different time intervals after exogenous application of plant hormone, Jasmonic acid (JA), and a JA blocker (Ibuprofen). Additional experiments by feeding FAW with leaf infused diet, fresh leaves, and a short-term exposure of FAW to the lines were also carried out. FAW mass gain, growth and development, and host ecophysiological traits were observed. In addition, we also quantified the major surface defenses- trichomes, and wax before and after herbivory. Our results show that FAW response did not vary between mutants and wild type rice. Meanwhile, we found plant hormonal application influenced the ecophysiological traits regardless of mutants and wild type rice. Collectively, we show that while defense against FAW in rice is JA mediated, SnRK1 has a limited role as observed through manipulative experiments with the wild type and snrk1 mutant rice lines
Modeling Charging Current Dynamics at Microelectrodes and their Interfaces with Electrolyte and Insulators with a Focus on Microfabricated Gold Microband Electrodes on an SU-8 Substrate
Get PDFThe suitability of electrochemical methods for quantitative measurements at microdevices is influenced by the relatively large electrode-insulator interface-to-electrode area ratio, greatly impacting charging dynamics due to interactions among electrolyte, conductor material, and insulator layers. The resulting charging current can overwhelm the faradaic current from redox chemistry. The device studied here features a 70 μm × 100 μm electroactive window, hosts gold coplanar microband electrodes, and is insulated by SU-8, which serves as both overlayer and substrate. The overlayer defines the electroactive length and isolates the leads of the electrodes from the sample solution. Cyclic voltammetry in 0.10 M KCl yields an unexpected, nonlinear dependence of current on scan rate, which can be explained with two empirical approaches. The first employs an equivalent circuit model, involving leakage resistance and double-layer capacitance in parallel, to address both background processes and electrode imperfections as a function of scan rate. The second associates the enhanced current to a changing-chargeable area resulting from interface irregularities. Prior publications on alternative conductor-insulator materials are benchmarked in this study. The comparison of the materials shows that the charging dynamics for devices made with SU-8 lead to more favorable electrochemical performance than for those constructed with glass, epoxy, and silicon nitride, and under certain circumstances, polyimide
Liquid Crystalline Collagen Assemblies as Substrates for Directed Alignment of Human Schwann Cells
Get PDFCollagen is a key component of the extracellular matrix (ECM) and well-oriented domains of collagen are important for mimicking the local cell environment in vitro. While there has been significant attention directed towards the alignment of collagen, formation of large-scale oriented domains remains a key challenge. Type I collagen self-assembles to form liquid crystalline (LC) mesophases in acidic conditions at concentrations above 100 mg mL−1. The LC mesophase provides an efficient platform for large-scale alignment and patterning of collagen coated substrates. However, there still exist challenges related to solubilizing and processing of collagen at such high concentrations in order to replicate the native ECM. In this contribution, we report on centimeter-scale alignment in collagen-coated glass substrates using solutions that are well below the LC-forming concentrations. Importantly, we are also able to extend this method to macroscopic 3-D LC-collagen hydrogels with programmed anisotropy within them to create a mimic of the native ECM. We show that the orientation and aspect ratio of human Schwann cells are strongly coupled with the alignment of the collagen substrate/hydrogel. We use a simple model to estimate the critical magnetic field strength needed for a given concentration of collagen to permit macroscopic alignment-enabling guidance for future studies on alignment of collagen at high concentrations
Geometric Principles in Architecture Aesthetics
Get PDFThis study focuses on geometric formalism in three major monuments across different architectural eras in time. The use of three distinct geometric principles to outline the use of pure or manufactured shapes and figures helps to discover and isolate an aesthetic component of architecture within which it is contained. A collection of studies are implemented and are focused on orthographic drawings from each monument in horizontality and verticality, consisting of a dual set of overlay and interpretative drawings for each type of orthographic representation for each monument. A discussion follows and highlights the changes or similarities over time the role that geometry and its principles play in architecture aesthetics. These monuments will then be given a score of Aesthetic Measure using a variation of George Birkhoff’s formula. The buildings’ scores will be a mixture of the order of the organization of the plan and section/elevation and how well the monument is laid out, in tandem with the plan and section. These buildings will then be inversely related by their complexity of geometry and/or hierarchy of spaces, resulting in a score that can range logarithmically from negative to neutral to positive, or more plainly between 0 and 1, to 1, to greater than 1
Exercise-Induced MYC as an Epigenetic Reprogramming Factor That Combats Skeletal Muscle Aging
Get PDFOf the “Yamanaka factors” Oct3/4, Sox2, Klf4, and c-Myc (OSKM), the transcription factor c-Myc (Myc) is the most responsive to exercise in skeletal muscle and is enriched within the muscle fiber. We hypothesize that the pulsatile induction of MYC protein after bouts of exercise can serve to epigenetically reprogram skeletal muscle toward a more resilient and functional state