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Articles 1471 - 1500 of 13646
Full-Text Articles in Physical Sciences and Mathematics
How To Catch When Proxies Lie: Verifying The Physical Locations Of Network Proxies With Active Geolocation, Zachary Weinberg, Shinyoung Cho, Nicolas Christin, Vyas Sekar, Phillipa Gill
How To Catch When Proxies Lie: Verifying The Physical Locations Of Network Proxies With Active Geolocation, Zachary Weinberg, Shinyoung Cho, Nicolas Christin, Vyas Sekar, Phillipa Gill
Computer Science: Faculty Publications
Internet users worldwide rely on commercial network proxies both to conceal their true location and identity, and to control their apparent location. Their reasons range from mundane to security-critical. Proxy operators offer no proof that their advertised server locations are accurate. IP-to-location databases tend to agree with the advertised locations, but there have been many reports of serious errors in such databases. In this study we estimate the locations of 2269 proxy servers from ping-time measurements to hosts in known locations, combined with AS and network information. These servers are operated by seven proxy services, and, according to the operators, …
Interfacing Nickel Nitride And Nickel Boosts Both Electrocatalytic Hydrogen Evolution And Oxidation Reactions, Fuzhan Song, Wei Li, Jiaqi Yang, Guanqun Han, Peilin Liao, Yujie Sun
Interfacing Nickel Nitride And Nickel Boosts Both Electrocatalytic Hydrogen Evolution And Oxidation Reactions, Fuzhan Song, Wei Li, Jiaqi Yang, Guanqun Han, Peilin Liao, Yujie Sun
Chemistry and Biochemistry Faculty Publications
Electrocatalysts of the hydrogen evolution and oxidation reactions (HER and HOR) are of critical importance for the realization of future hydrogen economy. In order to make electrocatalysts economically competitive for large-scale applications, increasing attention has been devoted to developing noble metal-free HER and HOR electrocatalysts especially for alkaline electrolytes due to the promise of emerging hydroxide exchange membrane fuel cells. Herein, we report that interface engineering of Ni3N and Ni results in a unique Ni3N/Ni electrocatalyst which exhibits exceptional HER/HOR activities in aqueous electrolytes. A systematic electrochemical study was carried out to investigate the superior hydrogen …
U.S. College Students’ Social Network Characteristics And Perceived Social Exclusion: A Comparison Between Drinkers And Nondrinkers Based On Pastmonth Alcohol Use, Sara G. Balestrieri, Graham T. Diguiseppi, Matthew Meisel, Melissa A. Clark, Miles Q. Ott, Nancy P. Barnett
U.S. College Students’ Social Network Characteristics And Perceived Social Exclusion: A Comparison Between Drinkers And Nondrinkers Based On Pastmonth Alcohol Use, Sara G. Balestrieri, Graham T. Diguiseppi, Matthew Meisel, Melissa A. Clark, Miles Q. Ott, Nancy P. Barnett
Statistical and Data Sciences: Faculty Publications
There is a general perception on college campuses that alcohol use is normative. However, nondrinking students account for 40% of the U.S. college population. With much of the literature focusing on intervening among drinkers, there has been less of a focus on understanding the nondrinker college experience. The current study has two aims: to describe the social network differences between nondrinkers and drinkers in a college setting, and to assess perceived social exclusion among nondrinkers. METHOD:First-year U.S. college students (n = 1,342; 55.3% female; 47.7% non-Hispanic White) were participants in a larger study examining a social network of one college …
Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter
Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter
USF Tampa Graduate Theses and Dissertations
Three ice cores and one guano core were obtained from lava tubes in El Malpais National Monument, New Mexico, in the Southwest United States. A large hiatus in the Bat Cave guano record, resulting from mining activities in the early 1900's, left us with only ~50 years of data (from AD 1955-2006) to use in analysis. 13C values in guano (-18 to -11.6‰) primarily fall within the range of C4 plants, and likely indicate a tendency of Tadarida brasiliensis to feed on insects over grasslands to the North or South of the park. Variations in 13C values for this period …
Do Slow Slip Events Trigger Large And Great Megathrust Earthquakes?, N. Voss, Timothy H. Dixon, Z. Liu, Rocco Malservisi, M. Protti, S. Schwartz
Do Slow Slip Events Trigger Large And Great Megathrust Earthquakes?, N. Voss, Timothy H. Dixon, Z. Liu, Rocco Malservisi, M. Protti, S. Schwartz
School of Geosciences Faculty and Staff Publications
Slow slip events have been suggested to trigger subduction earthquakes. However, examples to date have been poorly recorded, occurring offshore, where data are sparse. Better understanding of slow slip events and their influence on subsequent earthquakes is critical for hazard forecasts. We analyze a well-recorded event beginning 6 months before the 2012 Mw (moment magnitude) 7.6 earthquake in Costa Rica. The event migrates to the eventual megathrust rupture. Peak slip rate reached a maximum of 5 mm/day, 43 days before the earthquake, remaining high until the earthquake. However, changes in Mohr-Coulomb failure stress at the hypocenter were small (0.1 …
Several Levels Of Theory For Description Of Isotope Effects In Ozone: Effect Of Resonance Lifetimes And Channel Couplings, Alexander Teplukhin, Dmitri Babikov, Igor Gayday
Several Levels Of Theory For Description Of Isotope Effects In Ozone: Effect Of Resonance Lifetimes And Channel Couplings, Alexander Teplukhin, Dmitri Babikov, Igor Gayday
Chemistry Faculty Research and Publications
In this paper, two levels of theory are developed to determine the role of scattering resonances in the process of ozone formation. At the lower theory level, we compute resonance lifetimes in the simplest possible way, by neglecting all couplings between the diabatic vibrational channels in the problem. This permits to determine the effect of “shape” resonances, trapped behind the centrifugal barrier and populated by quantum tunneling. At the next level of theory, we include couplings between the vibrational channels, which permits to determine the role of Feshbach resonances and interaction of different reaction pathways on the global PES of …
Development Of Betulinic Acid Triazole Conjugates As Potential Anti-Cancer Agents, Gayathri Jampana
Development Of Betulinic Acid Triazole Conjugates As Potential Anti-Cancer Agents, Gayathri Jampana
Theses and Dissertations
Betulin and betulinic acid are pentacyclic triterpenoid natural product isolated from the bark of birch trees. While betulin is abundantly available in the bark, betulinic acid is present in scarce quantities in nature. However, betulinic acid can be conveniently synthesized from betulin via simple redox manipulations. Betulinic acid shows selective cytotoxicity profile against cancer cells in vitro while being relatively safe for normal cells. One of the challenges for the clinical development of betulinic acid is its lack of aqueous solubility. The three key structural features of betulin/betulinic acid that have been routinely exploited for structural modifications to enhance their …
Remote Estimation Of Surface Water PCo2 In The Gulf Of Mexico, Shuangling Chen
Remote Estimation Of Surface Water PCo2 In The Gulf Of Mexico, Shuangling Chen
USF Tampa Graduate Theses and Dissertations
Surface ocean partial pressure of CO2 (pCO2) is a critical parameter in the quantification of air-sea CO2 flux, which further plays an important role in quantifying the global carbon budget and understanding ocean acidification. The demand for a clearer understanding of how, and how fast, the ocean is changing due to atmospheric CO2 absorption, requires accurate and synoptic estimation of surface pCO2.
Surface ocean pCO2 is mainly controlled by four oceanic processes – thermodynamics, ocean mixing, biological activities, and air-sea CO2 exchange. Surface ocean pCO2 …
Emerging Models Of Nitrogen And Carbon Cycling In Engineered Wastewater Treatment Processes, Kartik Chandran
Emerging Models Of Nitrogen And Carbon Cycling In Engineered Wastewater Treatment Processes, Kartik Chandran
Sustainability Seminar Series
The engineered nitrogen cycle provides a rich framework to study the structure, function and interactions within mixed microbial communities. The knowledge objtained from such studies also allows us to harness the potential of such communities towards achieving multiple goals including the production of clean water, treatment of drinking water and the synthesis of commodity chemicals and fuels, among others. Within the spectrum of engineered nitrogen cycling processes, autotrophic biological nitrogen removal (BNR) offers an energy and resource efficient alternate to conventionally followed approaches. The successful implementation of autotrophic BNR processes is contingent upon the selective retention of aerobic and anaerobic …
Impact Of Iudr In Rat 9l Glioma Cell Survival For 25-35 Kev Photo-Activated Auger Electron Therapy, Diane Alvarez
Impact Of Iudr In Rat 9l Glioma Cell Survival For 25-35 Kev Photo-Activated Auger Electron Therapy, Diane Alvarez
Diane Alvarez
Introduction: Photo-activated Auger electron therapy is a potential technique that could preferentially target cancer cells. This binary therapy uses a drug containing a high-Z element like iododeoxyuridine (IUdR), which serves as a radiosensitizer and molecular carrier of high-Z iodine into cancer cell DNA. Iodine becomes the Auger electron source when activated by photons with an appropriate energy. This work studied the survival of rat 9L glioma cells with IUdR replacing thymidine in the DNA. Irradiations at monochromatic energies above and below the iodine K-edge (33.2 keV) are part of a larger study from 25-70 keV. It was hypothesized that SER10 …
Managing Risk In Grazing Operations, Christopher D. Teutsch, Kenneth H. Burdine
Managing Risk In Grazing Operations, Christopher D. Teutsch, Kenneth H. Burdine
Kentucky Grazing Conference
Risk is an inherent part of agricultural production systems. Crane and coworkers (2013) identified five primary areas of risk in grazing operations: 1) MARKETING risk, 2) PRODUCTION risk, 3) LEGAL risk, 4) HUMAN risk, and FINANCIAL risk. These types of risk are described in the accompanying publication entitled “Controlling Risk in Grazing-Based Production Systems” by J. Parsons. This article will discuss the risk associated with “production” in grazing systems, focusing specifically on managing drought in grass based production operations.
Keys To Optimizing Profitability In Cow-Calf Production -- Rooster's Beef, 3 Generations Of Farming & Beef, William Slaton, Becky Slaton
Keys To Optimizing Profitability In Cow-Calf Production -- Rooster's Beef, 3 Generations Of Farming & Beef, William Slaton, Becky Slaton
Kentucky Grazing Conference
Rooster's Beef ultimately began with our family farm -Rocky Bluff Farm - now owned by William and Becky Slaton. It is the cattle producer for our beef sold. The farm is named after two Natural Rock Formations on our property. We have several acres of pasture and including some wooded acres. With rotational grazing and intense management, we are able to have 65 cows in a spring calving group, 15 cows in a fall calving group, 3 bulls, 13 replacement heifers, unweaned calves and 12 calves on finisher feed. We also rent ground to raise and put up our own …
Grass Finished Beef: Melding Production And Marketing [2], Todd Clark
Grass Finished Beef: Melding Production And Marketing [2], Todd Clark
Kentucky Grazing Conference
No abstract provided.
Grass Finished Beef: Melding Production And Marketing [1], Michael Palmer, Stacie Palmer
Grass Finished Beef: Melding Production And Marketing [1], Michael Palmer, Stacie Palmer
Kentucky Grazing Conference
Palmer Farms Beef is a family farm near Murray KY, owned by Michael and Stacie Palmer. We produce, and retail around 40 beef per year.
Turning Grass Into Cash With Small Ruminants, Kenneth Andries
Turning Grass Into Cash With Small Ruminants, Kenneth Andries
Kentucky Grazing Conference
As agriculture continues to change, it is important to consider sustainability before starting or expanding any enterprise. One critical factor in any animal agriculture enterprise is controlling feeding costs. Most research indicates feeding is the largest expenses in any livestock enterprise. However, nutrition is critical to overall productivity and the income of the enterprise. Because of this, producers need to find ways to improve nutrient availability while minimizing costs to optimize production and profitability for their livestock enterprise.
Grazing Dairies: Challenges And Opportunities, Howard Straub Iii
Grazing Dairies: Challenges And Opportunities, Howard Straub Iii
Kentucky Grazing Conference
No abstract provided.
Considerations For Making A Profit With Stocker Cattle, Jeff Lehmkuhler
Considerations For Making A Profit With Stocker Cattle, Jeff Lehmkuhler
Kentucky Grazing Conference
The southeast is home to more than 7.3 million beef cows (USDA 2018). At an estimated 80% weaning rate and 20% heifer retention, the southeast region would be expected to produce more than 4.6 million feeder calves that would go to market in 2018. The cow-calf industry in the region provides an opportunity for the stocker and backgrounding operations to co-exist. Much of the land in the region is best suited for forage and pasture production, which at the current moment, provides a low cost feed for adding pounds to light weight feeder cattle. Yet, the stocker and backgrounding segments …
Measuring Profitability In Grazing Operations, Kenneth H. Burdine
Measuring Profitability In Grazing Operations, Kenneth H. Burdine
Kentucky Grazing Conference
When producers make investments in extending their grazing season, they do so in order to obtain an economic benefit. These benefits usually include a reduction in the number of days that stored feed (typically hay) is fed, an increase in carry capacity or stocking rate, or an increase in production level (rates of gain, weaning weights, etc). While all of these are potential benefits of improved grazing systems, a reduction in winter feeding days is often the simplest way to start. When the grazing season is extended, winter feeding days are reduced, and this cost savings can be weighed against …
Foreword And Conference Information [2018], S. Ray Smith, Christopher D. Teutsch
Foreword And Conference Information [2018], S. Ray Smith, Christopher D. Teutsch
Kentucky Grazing Conference
No abstract provided.
Ground-Truthing Social Vulnerability Indices Of Alaska Fishing Communities, Anna Lavoie, Kim Sparks, Stephen Kasperski, Amber Himes-Cornell, Kristin Hoelting, Conor Maguire
Ground-Truthing Social Vulnerability Indices Of Alaska Fishing Communities, Anna Lavoie, Kim Sparks, Stephen Kasperski, Amber Himes-Cornell, Kristin Hoelting, Conor Maguire
All Faculty Scholarship for the College of the Sciences
Community vulnerability is increasingly evaluated through quantitative social indices, typically developed using secondary data sources rather than primary data collection. It is necessary to understand the validity of these indices if they will be used to inform policy and decision making. This paper presents a ground-truthing effort to validate quantitative indices that characterize the well-being of Alaska fishing communities. We utilized ethnographic data collected from 13 representative communities and a capital assets framework to ground-truth the indices, in which qualitative ranks of vulnerability were compared against quantitative indices. The majority (73.8%) of ranks were in complete or moderate agreement and …
Synthesis Of Some Fossils Of Ferrocene Carboxylic Acid And Their Classification Based On Tif Tn, Н Tulakov,, I. Askarov,, Yu. Isaeva,, K. Otaxonov
Synthesis Of Some Fossils Of Ferrocene Carboxylic Acid And Their Classification Based On Tif Tn, Н Tulakov,, I. Askarov,, Yu. Isaeva,, K. Otaxonov
Scientific journal of the Fergana State University
The synthesis of some ferrocenecarboxylic acid derivatives and assignment of code numbers for them according to the commodity nomenclature of foreign economic activity (CN FEA) is described in the article.
Study Of Speech Familiar Topics Using Artificial Neural Networks, А. Abdukadirov,, D Umurzakov
Study Of Speech Familiar Topics Using Artificial Neural Networks, А. Abdukadirov,, D Umurzakov
Scientific journal of the Fergana State University
Create a neural network mode for recognition of separate words solution, analyze training characteristics and behavior of constructed neural network. Target network had to be portable to DSP platforms that define a format of input data.
Comparison Of Theoretical And Experimental Geometric Characteristics Of Betulin, A. Eshimbetov,, Sh Kurbanbaeva,, Sh. Turgunbaev,, A. Xaitbaev
Comparison Of Theoretical And Experimental Geometric Characteristics Of Betulin, A. Eshimbetov,, Sh Kurbanbaeva,, Sh. Turgunbaev,, A. Xaitbaev
Scientific journal of the Fergana State University
The study of betulin and its derivatives is of great importance, since the programs of mathematical modeling enable a qualitative study of the relationship between structure-spectrum-properties. As a result of the theoretical search, it is possible to determine still non-synthesized highly-biologically active derivatives of betulin
About The Estimate Of The Sum Of The Random Number Of Random Numbers, I. Nematov, S. Kukieva
About The Estimate Of The Sum Of The Random Number Of Random Numbers, I. Nematov, S. Kukieva
Scientific journal of the Fergana State University
In this paper we consider the estimate of the maximum of the sums of a random number of independent random variables
One Way To Increase Natural Numbers, A. Yusupova,, S. Uktamova
One Way To Increase Natural Numbers, A. Yusupova,, S. Uktamova
Scientific journal of the Fergana State University
In this paper we consider one of the convenient methods for computing the multiplication of natural numbers.
The 55 Cancri System Reassessed, Vincent Bourrier, Xavier Dumusque, Caroline Dorn, Gregory W. Henry, Nicola Astudillo-Defru, Javiera Rey, Björn Benneke, Guillaume Hébrard, Christophe Lovis, Brice-Olivier Demory, C. Moutou, David Ehrenreich
The 55 Cancri System Reassessed, Vincent Bourrier, Xavier Dumusque, Caroline Dorn, Gregory W. Henry, Nicola Astudillo-Defru, Javiera Rey, Björn Benneke, Guillaume Hébrard, Christophe Lovis, Brice-Olivier Demory, C. Moutou, David Ehrenreich
Information Systems and Engineering Management Research Publications
Orbiting a bright, nearby star the 55 Cnc system offers a rare opportunity to study a multiplanet system that has a wide range of planetary masses and orbital distances. Using two decades of photometry and spectroscopy data, we have measured the rotation of the host star and its solar-like magnetic cycle. Accounting for this cycle in our velocimetric analysis of the system allows us to revise the properties of the outermost giant planet and its four planetary companions. The innermost planet 55 Cnc e is an unusually close-in super-Earth, whose transits have allowed for detailed follow-up studies. Recent observations favor …
Resurrecting The Regulatory Properties Of The Ostreococcus Tauri Adp-Glucose Pyrophosphorylase Large Subunit, Carlos M. Figueroa, Misty L. Kuhn, Benjamin L. Hill, Alberto A. Iglesias, Miguel A. Ballicora
Resurrecting The Regulatory Properties Of The Ostreococcus Tauri Adp-Glucose Pyrophosphorylase Large Subunit, Carlos M. Figueroa, Misty L. Kuhn, Benjamin L. Hill, Alberto A. Iglesias, Miguel A. Ballicora
Chemistry: Faculty Publications and Other Works
ADP-glucose pyrophosphorylase (ADP-Glc PPase) catalyzes the first committed step for the synthesis of glycogen in cyanobacteria and starch in green algae and plants. The enzyme from cyanobacteria is homotetrameric (α4), while that from green algae and plants is heterotetrameric (α2β2). These ADP-Glc PPases are allosterically regulated by 3-phosphoglycerate (3PGA, activator) and inorganic orthophosphate (Pi, inhibitor). Previous studies on the cyanobacterial and plant enzymes showed that 3PGA binds to two highly conserved Lys residues located in the C-terminal domain. We observed that both Lys residues are present in the small (α) subunit of the Ostreococcus tauri enzyme; however, one of these …
A Mixed Method Study Of Prospective Teachers' Epistemic Beliefs And Web Evaluation Strategies Concerning Hoax Websites, Jennifer Coccaro-Pons
A Mixed Method Study Of Prospective Teachers' Epistemic Beliefs And Web Evaluation Strategies Concerning Hoax Websites, Jennifer Coccaro-Pons
FIU Electronic Theses and Dissertations
Teachers need to be equipped with the tools necessary to evaluate content on the Internet and determine if it is a credible source, or a hoax website since they are expected to instruct and prepare students on how to evaluate the sites which is now a relevant phenomenon. The purpose of the mixed‑method study was to obtain an understanding of the web evaluation strategies of prospective teachers regarding the evaluation of hoax websites and how their epistemic beliefs may influence their evaluation. Another aspect of this study was to find out what outcomes resulted from providing guidance, or not to …
Dependence Of Nmr Chemical Shifts Upon Ch Bond Lengths Of A Methyl Group Involved In A Tetrel Bond, Steve Scheiner
Dependence Of Nmr Chemical Shifts Upon Ch Bond Lengths Of A Methyl Group Involved In A Tetrel Bond, Steve Scheiner
Chemistry and Biochemistry Faculty Publications
Four different Lewis acids that might participate in a tetrel bond with a nucleophile (SEt2Me+, NMe4+, SMe2, NMe3) are examined. The NMR chemical shifts of the methyl C and H atoms are calculated as the CH bond lengths are systematically stretched and contracted, in the absence of a base. The C shielding diminishes by roughly 2 ppm for a stretch of 0.01 Å, while that of H drops by only 0.3 ppm. The deshieldings caused purely by the bond length changes are far too small to account for the …
Acidity And Antioxidant Activity Of Cold Brew Coffee., Niny Z. Rao, Megan Fuller
Acidity And Antioxidant Activity Of Cold Brew Coffee., Niny Z. Rao, Megan Fuller
College of Life Sciences Faculty Papers
The acidity and antioxidant activity of cold brew coffee were investigated using light roast coffees from Brazil, two regions of Ethiopia, Columbia, Myanmar, and Mexico. The concentrations of three caffeoylquinic acid (CQA) isomers were also determined. Cold brew coffee chemistry was compared to that of hot brew coffee prepared with the same grind-to-coffee ratio. The pH values of the cold and hot brew samples were found to be comparable, ranging from 4.85 to 5.13. The hot brew coffees were found to have higher concentrations of total titratable acids, as well as higher antioxidant activity, than that of their cold brew …