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The Hubble PanCET program: Transit and Eclipse Spectroscopy of the Hot-Jupiter WASP-74b
Get PDFPlanets are like children with each one being unique and special. A better understanding of their collective properties requires a deeper understanding of each planet. Here we add the transit and eclipse spectra of hot-Jupiter WASP-74b into the ever growing data set of exoplanet atmosphere spectral library. With six transits and three eclipses using the Hubble Space Telescope and Spitzer Space Telescope (Spitzer), we present the most complete and precise atmospheric spectra of WASP-74b. We found no evidence for TiO/VO nor super-Rayleigh scattering reported in previous studies. The transit shows a muted water feature with strong Rayleigh scattering extending into the infrared. The eclipse shows a featureless blackbody-like WFC3/G141 spectrum and a weak methane absorption feature in the Spitzer 3.6 μm band. Future James Webb Space Telescope follow-up observations are needed to confirm these results
Soil Bacteria in Urban Community Gardens Have the Potential to Disseminate Antimicrobial Resistance Through Horizontal Gene Transfer
Get PDFFifteen soil and 45 vegetable samples from Detroit community gardens were analyzed for potential antimicrobial resistance contamination. Soil bacteria were isolated and tested by antimicrobial susceptibility profiling, horizontal gene transfer, and whole-genome sequencing. High-throughput 16S rRNA sequencing analysis was conducted on collected soil samples to determine the total bacterial composition. Of 226 bacterial isolates recovered, 54 were from soil and 172 from vegetables. A high minimal inhibitory concentration (MIC) was defined as the MIC greater than or equal to the resistance breakpoint of Escherichia coli for Gram-negative bacteria or Staphylococcus aureus for Gram-positive bacteria. The high MIC was observed in 63.4 and 69.8% of Gram-negative isolates from soil and vegetables, respectively, against amoxicillin/clavulanic acid, as well as 97.5 and 82.7% against ampicillin, 97.6 and 90.7% against ceftriaxone, 85.4 and 81.3% against cefoxitin, 65.8 and 70.5% against chloramphenicol, and 80.5 and 59.7% against ciprofloxacin. All Gram-positive bacteria showed a high MIC to gentamicin, kanamycin, and penicillin. Forty of 57 isolates carrying tetM (70.2%) successfully transferred tetracycline resistance to a susceptible recipient via conjugation. Whole-genome sequencing analysis identified a wide array of antimicrobial resistance genes (ARGs), including those encoding AdeIJK, Mex, and SmeDEF efflux pumps, suggesting a high potential of the isolates to become antimicrobial resistant, despite some inconsistency between the gene profile and the resistance phenotype. In conclusion, soil bacteria in urban community gardens can serve as a reservoir of antimicrobial resistance with the potential to transfer to clinically important pathogens, resulting in food safety and public health concerns
Identification and genetic characterization of Pseudomonas syringae pv. syringae from sweet cherry in Turkey
Get PDFPseudomonas syringae pv. syringae (Pss), which causes bacterial canker, is the most polyphagous bacterium in the P. syringae complex due to its broad host range. This pathogen is considered the major bacterial disease in cherry orchards. In this study, several samples were collected from infected sweet cherry trees in different locations of the Marmara region in Turkey between 2016-2018. Sixty-three isolates were identified as Pss by pathogenicity, LOPAT, GATTa, and MALDI-TOF MS tests. Total genomic DNA was extracted to confirm identity, followed by PCR amplification of syrB and cfl genes. Out of 63 isolates, 12 were randomly selected for Repetitive Element Sequence-based PCR (rep-PCR) and Multilocus Sequence Typing (MLST) analysis to gain insight into the relationships of those isolates. The cluster analysis of rep-PCR (ERIC-, REP- and BOX-PCR) could classify the isolates into two distinct clusters. Phylogenetic analysis was carried out to obtain the relation between isolates and the location.The MLST analysis of gyrB, rpoDp, rpoDs, and gltA genes allowed a clear allocation of the isolates into two separate main clusters. The relationship among the isolates were also evaluated by constructing a genealogical median-joining network (MJN). The isolates from six locations produced 11 haplotypes that were illustrated in the MJN. The results of this study proved that location could not be an indicator for showing the genetic diversity of Pss from cherry orchards. As the genetic variability of Pseudomonads has been demonstrated, the current study also showed high diversity among different isolates even within the populations. While more research is recommended, the results of this study contributed to a better understanding of the Pss evolutionary progress and genetic diversity of sweet cherry isolates
Economic Analysis of Investment Opportunities for Alfalfa Pellet Production
No full textAlfalfa has considerable potential as high quality hay because of its high biomass production, perennial nature, ability to provide its own nitrogen fertilizer, and valuable co-products. Despite the potential for alfalfa as an important leguminous cover crop and by-products for animal feed, little research has been conducted in Tennessee and other southeastern states on its adaptability to various climatic conditions, or its profitability and market feasibility. Increased adaptation of alfalfa in current production systems is an important factor in sustainable agriculture. The aim of this study is to analyze the farmers’ perceptions of incorporating Alfalfa into production systems and evaluate the profitability of producing Alfalfa hay and pellets for feed market. The specific objectives of the research are to a.) analyze the structural changes in alfalfa hay market b.) evaluate the economic feasibility of investment for alfalfa palletization and c.) identify factors affecting willingness to invest for alfalfa palletization. The profitability analysis was based on secondary data including enterprise budgets from various university extension services and other published data sources. The pert distribution was used to measure the variation of input costs, yield and market price. The variability of net return was calculated using stochastic profit function. Monte Carlo simulation was performed to estimate profitability. The analysis show positive net return from alfalfa hay production. According to the sensitivity analysis, the selling price and hay yield were positively correlated with net return while unit production costs was negatively correlated with Alfalfa yield. Among these two variables, Alfalfa price is more correlated with net return. Considering financial constraints face by the small farmers, small scale palletization mills with two different capacities were used to analyze pellet production. Comparison of net return from Alfalfa hay vs pellet production shows slight advantage in processing hay into pellets than traditional hay production. Producer survey was conducted to identify producer’s willingness to invest for small scale alfalfa palletization unit. The analysis of binomial logit regression model shows mixed results. The findings of the study is useful to identify the opportunities and constraints in alfalfa hay production and how relevant it is for current and future famers in making investment decisions
Comparing Chronic Treatments of the INI and VSV Isoforms of the Human Serotonin 2C Receptor Impacting Phosphorylation of STAT3
No full textSerotonin (5-HT), an indolamine neurotransmitter derivative of tryptophan, is located solely in the central nervous system, as well as the peripheral nervous system. 5-HT has a significant role in the human anatomy due to its involvement in an abundance of physiological functions such as modulating cognitive ability, appetite, mood, sleeping patterns, neuronal excitability, and homeostasis of glucose and energy. 5-HT elicits its effects by binding to at least 14 different receptor subtypes, one in particular, 5-HT2C. Previously discovered as a 7-transmembrane spanning G protein-coupled receptor (GPCR), the 5-HT2C receptor subtype is only GPCR currently to perform RNA editing, resulting in at least 14 different isoforms in the human brain. In addition, this receptor has served as a target for atypical antipsychotic medication in order to treat patients compromised with psychological deficiencies. The 5-HT2C receptor has also been considered a prime research candidate in intercellular activity due to its ability to influence signaling pathways of several proteins. The purpose of this study was to determine to what extent the human 5-HT2C receptor manipulates phosphorylated activity of the STAT3 protein in the JAK/STAT pathway by comparing two different receptor isoforms exposed to chronic drug treatments. Human Embryonic Kidney (HEK) 293 cells were transfected with human 5-HT2C receptors in the INI or VSV isoform. 5-HT2C-INI/VSV receptor transfected cells were treated with control, 5-HT, water, olanzapine, SB206553, or MK-212 for 1 hour and were also tested against untransfected HEK cells. All of the previous conditioned cells were made into lysates, proteins were separated by SDS-PAGE, and levels of phosphorylated STAT3 and unphosphorylated STAT3 were analyzed using western blots. NBT/BCIP developing solution detected untransfected cell (control) samples to contain and express phosphorylated STAT3 bands. The control was not supposed to have any protein bands present after antibody detection. This problem indicated that the particular experimental cells might have already contained a particular 5-HT2C receptor without our knowledge beforehand. Experiments will need to be restarted under the same transfections and 1 hour stimulations, but with completely new source of HEK293 cells
Predicting the Thermodynamic Stability of Perovskite Structures through Machine Learning
No full textPerovskites solar cells have been improved tremendously over the years, making them a material of interest in the solar photovoltaic (PV) world. However, the perovskite material is limited by the thermodynamic instability of its structure. Creating and testing of structural and molecular combinations in a laboratory is expensive and time consuming as there is a plethora of these combinations. The thermodynamic instability of perovskite materials can be improved through various chemical processes; however, this research focuses on component choice alteration to tackle this. This component choice alteration is facilitated by machine learning, where energy above convex hull of the analyzed perovskite structures is used as basis for the prediction of stable materials. On the other hand, machine learning, using presently available data, can be used to predict the molecular system in which the structural frame is more likely thermodynamically stable. In this research project, seven supervised classification machine learning models have been developed to predict the stability of perovskite structures with different molecular systems. Two datasets (sample size 1,929 for Dataset 1 and 5,329 for Dataset 2) which consist of perovskite structural compounds are evaluated for this project. The models, which include logistic regression, K nearest neighbors (KNN), decision tree, random forest, support vector machine (SVM), multi-layer perceptron, and gradient boosting are used to predict the thermodynamic stability of the perovskite structures, and the results of these different models are compared. Random Forest model performed best for the prediction of thermodynamic stability of within these datasets with accuracy of 96.6% for Dataset 1 and 94.9% for Dataset 2
The Hubble PanCET Program: Transit and Eclipse Spectroscopy of the Strongly Irradiated Giant Exoplanet WASP-76b
Get PDFUltra-hot Jupiters with equilibrium temperatures greater than 2000 K are uniquely interesting targets as they provide us crucial insights into how atmospheres behave under extreme conditions. This class of giant planets receives intense radiation from their host star and usually has strongly irradiated and highly inflated atmospheres. At such a high temperature, cloud formation is expected to be suppressed and thermal dissociation of water vapor could occur. We observed the ultra-hot Jupiter WASP-76b with seven transits and five eclipses using the Hubble Space Telescope and the Spitzer Space Telescope (Spitzer) for a comprehensive study of its atmospheric chemical and physical processes. We detected TiO and H2O absorption in the optical and near-infrared transit spectrum. Additional absorption by a number of neutral and ionized heavy metals like Fe, Ni, Ti, and SiO help explain the short-wavelength transit spectrum. The secondary eclipse spectrum shows muted water feature but a strong CO emission feature in Spitzer\u27s 4.5 μm band indicating an inverted temperature pressure profile. We analyzed both the transit and eclipse spectra with a combination of self-consistent PHOENIX models and atmospheric retrieval. Both spectra were well fitted by the self-consistent PHOENIX forward atmosphere model in chemical and radiative equilibrium at solar metallicity, adding to the growing evidence that both TiO/VO and NUV heavy metals opacity are prominent NUV-optical opacity sources in the stratospheres of ultra-hot Jupiters
Assessing the impact of organic versus conventional agricultural management on soil hydraulic properties in a long-term experiment
Get PDFInvestigating the effects of various agricultural management systems on soil hydraulic properties in long-term field experiments allows farmers to evaluate their efficacy in mitigating the effects of droughts and floods, which are expected to intensify in the coming decades. This study\u27s main objective was to quantify soil structural and hydraulic properties in plots under organic manure, organic leguminous, and conventional agricultural management and related tillage practices at Rodale Institute\u27s Farming Systems Trial. Soil cores were collected at depths of 0–10, 10–20, and 20–30 cm and analyzed for soil water retention, saturated hydraulic conductivity (Ksat), soil organic C (SOC), bulk density, and particle size distribution. Management practices had a measurable effect on SOC and bulk density, but not on Ksat, the parameters of the soil water retention model (rm and σ), or the calculated indicator water content values: field capacity (θfc), wilting point (θwp), plant available water (θpaw), and air capacity (θAirCap). Tillage practices (no-tillage vs. tillage) had a measurable effect on SOC, bulk density and θAirCap, but not on Ksat, θfc, θwp, or θpaw. Significant differences by depth were observed for θfc, θwp, θpaw, θAirCap, SOC, and bulk density, but not for Ksat. Our results suggest that relatively minor differences between management practices may be insufficient for generating quantifiable differences in soil structure, and more substantial changes to management practices will be necessary to achieve the outcomes for developing climate-resilient agricultural soils
Factors Influencing the Adoption of Agritourism among Small Farmers in Tennessee
No full textFarms in the United States of America (USA) come in a variety of different sizes, and the size of the farm has great influence on the business opportunities of the agricultural establishment. The opportunities of a farm can not only greatly affect the owners, but also people of the community in which it resides. Around 90% of the farms in the USA are small, which have annual gross farm income of less than $350,000. Small farms have great disadvantages in the number of resources and financial opportunities in comparison to large farms. Their operators must think of ways to enhance their agricultural operations to increase the longevity of their enterprises, which are subject to survival risks.Agritourism could be one of the viable on-farm strategies for risk management and stable income of small farms. The objectives of this study are to assess the characteristics and attributes of agritourism participating small farms in Tennessee, and to analyze the factors that influence farm households’ decisions to participate in agritourism activities. To gather data, we administered a survey among small farm operations across the state of Tennessee. We used an appropriate statistical test comparing adopter and non-adopter farms and probit regression model to estimate decision model. We discussed the statistical test results assessing adopter and non-adopter differences across several attributes. Our decision model suggests that the social media, smartphone usage, hired labor, off-farm work, farm insurance, and perceived risk significantly influence the adoption of agritourism on small farm operation. The results and conclusions will help to advance understanding of future success of small farms and the communities. This study is expected to help develop and enhance alternative agricultural enterprises like agritourism to the benefit and well-being of farm families and communities. Those who make agricultural policies will have a chance to increase their own understanding on the importance of agritourism and farm diversification, which can cause them to develop plans of action for small farms in the future