Digital Commons Network^™

A Gradient Of Pollination Specialization In Three Species Of Bolivian Centropogon, Laura P. Lagomarsino, Nathan Muchhala

Faculty Publications

© 2019 Botanical Society of America Premise: Closely related plant species with overlapping ranges often experience competition for pollination services. Such competition can select for divergence in floral traits that attract pollinators or determine pollen placement. While most species in Centropogon (Campanulaceae: Lobelioideae) have flowers that suggest adaptation to bat or hummingbird pollination, actual pollinators are rarely documented, and a few species have a mix of traits from both pollination syndromes. We studied the pollination biology of a “mixed-syndrome” species and its co-occurring congeners to examine the relationship between floral traits and visitation patterns for Centropogon. Methods: Fieldwork at two …

Longleaf Pine Patch Dynamics Influence Ground-Layer Vegetation In Old-Growth Pine Savanna, Maria Paula Mugnani, Kevin M. Robertson, Deborah L. Miller, William J. Platt

Faculty Publications

© 2019 by the authors. Old-growth longleaf pine savannas are characterized by diverse ground-layer plant communities comprised of graminoids, forbs, and woody plants. These communities co-exist with variable-aged patches containing similar-aged trees of longleaf pine (Pinus palustris Mill.). We tested the conceptual model that physical conditions related to the cycle of longleaf pine regeneration (stand structure, soil attributes, fire effects, and light) influence plant species' composition and spatial heterogeneity of ground-layer vegetation. We used a chrono-sequence approach in which local patches represented six stages of the regeneration cycle, from open areas without trees (gaps) to trees several centuries old, based …

Genetics Of Variable Disease Expression Conferred By Inverse Gene-For-Gene Interactions In The Wheat-Parastagonospora Nodorum Pathosystem, Amanda R. Peters Haugrud, Zengcui Zhang, Jonathan K. Richards, Timothy L. Friesen, Justin D. Faris

Faculty Publications

The wheat-Parastagonospora nodorum pathosystem involves the recognition of pathogen-secreted necrotrophic effectors (NEs) by corresponding wheat NE sensitivity genes. This inverse gene-for-gene recognition leads to necrotrophic effector-triggered susceptibility and ultimately septoria nodorum blotch disease. Here, we used multiple pathogen isolates to individually evaluate the effects of the host gene-NE interactions Tan spot necrosis1-Stagonospora nodorum ToxinA (Tsn1-SnToxA), Stagonospora nodorum necrosis1-Stagonospora nodorum Toxin1 (Snn1-SnTox1), and Stagonospora nodorum necrosis3-B genome homeolog1-Stagonospora nodorum Toxin3 (Snn3-B1-SnTox3), alone and in various combinations, to determine the relative importance of these interactions in causing disease. Genetic analysis of a recombinant inbred wheat population inoculated separately with three P. nodorum …

Effect Of Alkali-Enhanced Biochar On Silicon Uptake And Suppression Of Gray Leaf Spot Development In Perennial Ryegrass, Meng Wang, Jim J. Wang, Negar D. Tafti, Clayton A. Hollier, Gerald Myers, Xudong Wang

Faculty Publications

Silicon (Si) is known to alleviate biotic and abiotic stress, and to reduce the development of fungal diseases in a number of different pathosystems. Biochar-based Si fertilizers, especially highly efficient alkali-enhanced biochar for recycling phytolith, has been recently proposed as a stress-alleviating amendment but its evaluation on plant disease development has not been investigated. In this study, several biochar–based Si fertilizers including raw biochar without alkaline enhancement (0 KB), alkali-enhanced biochars with KOH (10 KB), CaO (10CB), and K 2 CO 3 (10K2B) along with commonly-used mineral Si fertilizer wollastonite (WO) and calcium silicate slag (SL) were evaluated in a …

Field-Evolved Resistance Of Helicoverpa Zea (Boddie) To Transgenic Maize Expressing Pyramided Cry1a.105/Cry2ab2 Proteins In Northeast Louisiana, The United States, Gagandeep Kaur, Jianguo Guo, Sebe Brown, Graham P. Head, Paula A. Price, Silvana Paula-Moraes, Xinzhi Ni, Marcelo Dimase, Fangneng Huang

Faculty Publications

The corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), is a major target pest of pyramided Bt maize and cotton in the U.S. In 2017 and 2018, notable ear damage and larval survival of H. zea were observed on pyramided Cry1A.105/Cry2Ab2 maize in some fields in northeast Louisiana, U.S. The objective of this study was to determine if the field control problem was due to resistance development to the Bt proteins in plants. A total of 15 H. zea populations were collected from Bt and non-Bt maize plants in 2017 and 2018 in multiple locations in Louisiana, Florida, and Georgia. Diet-overlay …

Zinc Toxicity And Iron-Sulfur Cluster Biogenesis In Escherichia Coli, Huangen Ding

Faculty Publications

While zinc is an essential trace metal in biology, excess zinc is toxic to organisms. Previous studies have shown that zinc toxicity is associated with disruption of the (4Fe-4S] clusters in various dehydratases in Escherichia coli. Here, we report that the intracellular zinc overload in E. coli cells inhibits iron-sulfur cluster biogenesis without affecting the preassembled iron-sulfur clusters in proteins. Among the housekeeping iron-sulfur cluster assembly proteins encoded by the gene cluster iscSUA-hscBA-fdx-iscX in E. coli cells, the scaffold IscU, the iron chaperone IscA, and ferredoxin have strong zinc binding activity in cells, suggesting that intracellular zinc overload inhibits iron-sulfur …

Three-Dimensional Basin And Fault Structure From A Detailed Seismic Velocity Model Of Coachella Valley, Southern California, Rasheed Ajala, Patricia Persaud, Joann M. Stock, Gary S. Fuis, John A. Hole, Mark Goldman, Daniel Scheirer

Faculty Publications

The Coachella Valley in the northern Salton Trough is known to produce destructive earthquakes, making it a high seismic hazard area. Knowledge of the seismic velocity structure and geometry of the sedimentary basins and fault zones is required to improve earthquake hazard estimates in this region. We simultaneously inverted first P wave travel times from the Southern California Seismic Network (39,998 local earthquakes) and explosions (251 land/sea shots) from the 2011 Salton Seismic Imaging Project to obtain a 3-D seismic velocity model. Earthquakes with focal depths ≤10 km were selected to focus on the upper crustal structure. Strong lateral velocity …

Review Of The History Of Living Forever, Michael F. Russo

Faculty Publications

No abstract provided.

Accelerating Many-Nucleon Basis Generation For High Performance Computing Enabled Ab Initio Nuclear Structure Studies, Daniel Langr, Tomáš Dytrych, Kristina D. Launey, Jerry P. Draayer

Faculty Publications

We present the problem of generating a many-nucleon basis in SU(3) -scheme for ab initio nuclear structure calculations in a symmetry-adapted no-core shell model framework. We first discuss and analyze the basis construction algorithm whose baseline implementation quickly becomes a significant bottleneck for large model spaces and heavier nuclei. The outcomes of this analysis are utilized to propose a new scalable version of the algorithm. Its performance is consequently studied empirically using the Blue Waters supercomputer. The measurements show significant acceleration achieved with over two orders of magnitude speedups realized for larger model spaces.

Homoeostatic Maintenance Of Nonstructural Carbohydrates During The 2015–2016 El Niño Drought Across A Tropical Forest Precipitation Gradient, Lee Turin Dickman, Nate G. Mcdowell, Charlotte Grossiord, Adam D. Collins, Brett T. Wolfe, Matteo Detto, S. Joseph Wright, José A. Medina-Vega, Devin Goodsman, Alistair Rogers, Shawn P. Serbin, Jin Wu, Kim S. Ely, Sean T. Michaletz, Chonggang Xu, Lara Kueppers, Jeffrey Q. Chambers

Faculty Publications

Nonstructural carbohydrates (NSCs) are essential for maintenance of plant metabolism and may be sensitive to short- and long-term climatic variation. NSC variation in moist tropical forests has rarely been studied, so regulation of NSCs in these systems is poorly understood. We measured foliar and branch NSC content in 23 tree species at three sites located across a large precipitation gradient in Panama during the 2015–2016 El Niño to examine how short- and long-term climatic variation impact carbohydrate dynamics. There was no significant difference in total NSCs as the drought progressed (leaf P = 0.32, branch P = 0.30) nor across …

Rural-Urban Variation In Informal Work Activities In The United States, Leif Jensen, Ann R. Tickamyer, Tim Slack

Faculty Publications

Using a unique national-level household survey of informal labor in the United States, this paper examines the extent that rural versus urban residence influences the types and forms of participation in informal work activities. The informal economy consists of work activities that generate income or reduce expenditures outside the scope of state regulation in contexts where these activities otherwise would be regulated. Often associated with developing and transition economies, past research using both qualitative and quantitative methods demonstrate its prevalence in industrial and postindustrial economies. In the U.S., most of this research is geographically constrained or limited to specific subpopulations …

Effect Of Hot Water Treatment Of In-Shell Pecans On Physicochemical Properties And Consumer Acceptability Of Roasted Pecan Kernels, Karuna Kharel, Witoon Prinyawiwatkul, Veerachandra K. Yemmireddy, Charles J. Graham, Achyut Adhikari

Faculty Publications

The effect of hot water pre-treatment of in-shell pecans on physicochemical properties, consumer acceptance and purchase intent of dehulled and roasted kernels was evaluated. In-shell pecans were first subjected to hot water at 70, 80 and 90 °C for 8.6, 6.6 and 4.6 min respectively and kernels were later dry roasted at 160 °C for 10 min. The physicochemical properties of hot water treated and untreated nuts, before and after roasting were determined. Furthermore, consumer acceptance and purchase intent of the roasted kernels were determined. Hot water treatment, alone and subsequent roasting had minimal effect on pecans’ physicochemical properties. Consumers …

Effect Of Residual Chlorine And Organic Acids On Survival And Attachment Of Escherichia Coli O157: H7 And Listeria Monocytogenes On Spinach Leaves During Storage, Vijay Singh Chhetri, Marlene E. Janes, Joan M. King, William Doerrler, Achyut Adhikari

Faculty Publications

The use of sanitizers during produce wash operation is a common practice, but little is known about the effect of residual sanitizers on minimizing food safety risks associated with post-sanitizing cross-contaminations. This study investigated the effect of residual chlorine and organic acids on the survival and the attachment of E. coli O157:H7 and L. monocytogenes on spinach leaves during refrigerated storage. The pathogens were spot inoculated on chlorine (100 ppm), lactic acid (0.5%) and acetic acid (0.5%) treated leaves, and their survival during refrigerated storage (4 °C) was examined. A significant reduction (P < 0.05) in E. coli O157:H7 and L. monocytogenes populations was observed within 15 min of exposure on chlorine-treated leaves, with total reductions of 2.64 and 3.15 log CFU/cm2 respectively after 48 h. On 0.5% lactic acid treated leaves, the reduction in E. coli O157:H7 and L. monocytogenes population was 3.07 log CFU/cm2 (24 h) and 1.40 log CFU/cm2 (48 h), respectively. The effect of residual sanitizers was significantly greater on loosely attached populations compared to strongly attached populations. These results indicate that the residual sanitizers present on vegetable leaves after sanitizers wash may have a role in reducing the risks associated with post-sanitizing cross-contamination.

Functional Screening Of Genes From A Halophyte Wild Rice Relative Porteresia Coarctata In Arabidopsis Model Identifies Candidate Genes Involved In Salt Tolerance, Venkata R. Mangu, Disna Ratnasekera, Jonalyn C. Yabes, Rod A. Wing, Niranjan Baisakh

Faculty Publications

High soil salinity is one of the most important environmental stressors, and is an increasing concern under the alarmingly global climate uncertainties. Salinity affects the growth and productivity of food crops, including rice, and ultimately threatens global food security and sustainability. Conventional breeding efforts to develop salt tolerant rice varieties utilizing its primary gene pool have resulted in limited success due to the mutligenic inheritance of salt tolerance traits. On the other hand, Porteresia coarctata, the only halophyte wild rice, offers tremendous opportunities to improve salt tolerance in rice. However, reports on the characterization of its rich genetic resources are …

Registration Of ‘Clj01’ Rice, Adam N. Famoso, Dustin L. Harrell, Donald E. Groth, Manoch Kongchum, Ida Wenefrida, James H. Oard, Richard E. Zaunbrecher, Karen F. Bearb, Corey A. Conner, Gavin J. Guidry, Brijesh Angira, Xueyen Sha, Steven D. Linscombe

Faculty Publications

‘CLJ01’ (Reg. No. CV-152, PI 687326), a Clearfield (BASF) long-grain aromatic (Jazzman) rice (Oryza sativa L.) cultivar, was developed by the Louisiana State University Agricultural Center at the H. Rouse Caffey Rice Research Station near Crowley, LA, and approved for release by the director of the Louisiana Agricultural Experiment Station in 2018. CLJ01 is the first aromatic rice cultivar to be released for use with the Clearfield rice production systems. CLJ01 was derived from the cross ‘Jazzman’/08CLR004//RU0802146/3/RU1002146, made 2010 and advanced in 2014 as an F 4 row selection. Preliminary testing in 2015 indicated high yield potential and favorable agronomic …

Multi-Objective Optimized Genomic Breeding Strategies For Sustainable Food Improvement, Deniz Akdemir, William Beavis, Roberto Fritsche-Neto, Asheesh K. Singh, Julio Isidro-Sánchez

Faculty Publications

The purpose of breeding programs is to obtain sustainable gains in multiple traits while controlling the loss of genetic variation. The decisions at each breeding cycle involve multiple, usually competing, objectives; these complex decisions can be supported by the insights that are gained by applying multi-objective optimization principles to breeding. The discussion in this manuscript includes the definition of several multi-objective optimized breeding approaches within the phenotypic or genomic breeding frameworks and the comparison of these approaches with the standard multi-trait breeding schemes such as tandem selection, independent culling and index selection. Proposed methods are demonstrated with two empirical data …

A High-Spin Ground-State Donor-Acceptor Conjugated Polymer, Alex E. London, H. Chen, M.A. Sabuj, Joshua Tropp, M. Saghayezhian, Naresh Eedugurala, B.A. Zhang, Y. Liu, Xiaodan Gu, B.M. Wong, N. Rai, M.K. Bowman, Jason D. Azoulay

Faculty Publications

Interest in high-spin organic materials is driven by opportunities to enable far-reaching fundamental science and develop technologies that integrate light element spin, magnetic, and quantum functionalities. Although extensively studied, the intrinsic instability of these materials complicates synthesis and precludes an understanding of how fundamental properties associated with the nature of the chemical bond and electron pairing in organic materials systems manifest in practical applications. Here, we demonstrate a conjugated polymer semiconductor, based on alternating cyclopentadithiophene and thiadiazoloquinoxaline units, that is a ground-state triplet in its neutral form. Electron paramagnetic resonance and magnetic susceptibility measurements are consistent with a high-to-low spin …

Review Of Quantitative Methods For Supply Chain Resilience Analysis, Seyedmohsen Hosseini, Dmitry Ivanov, Alexandre Dolgui

Faculty Publications

Supply chain resilience (SCR) manifests when the network is capable to withstand, adapt, and recover from disruptions to meet customer demand and ensure performance. This paper conceptualizes and comprehensively presents a systematic review of the recent literature on quantitative modeling the SCR while distinctively pertaining it to the original concept of resilience capacity. Decision-makers and researchers can benefit from our survey since it introduces a structured analysis and recommendations as to which quantitative methods can be used at different levels of capacity resilience. Finally, the gaps and limitations of existing SCR literature are identified and future research opportunities are suggested.

Difference Of Opinion: Spousal Influence On Cancer Risk-Reducing Behavior, Wendy C. Birmingham, Maija Reblin, Wendy Kohlmann, Tyler Graff

Faculty Publications

Marriage is consistently associated with better health outcomes. Spouses' attempts to influence partners' lifestyle and general health behaviors may contribute to this effect, although partners may not be aware of this influence. Spousal worry of a cancer diagnosis for an at-risk partner may factor into attempts to influence. An examination of spousal worry and influence on lifestyle choices, general health behaviors, and cancer screening adherence for partners at higher risk of colorectal cancer may shed light on spousal influence and partners' perceptions of influence. Methods: A mixed-method design assessed cancer worry and spousal influence for risk-reducing behavior in first-degree relatives …

A Comparison Of Hominin Teeth From Lincoln Cave, Sterkfontein L/63, And The Dinaledi Chamber, South Africa, Juliet K. Brophy, Joel Irish, Steve E. Churchill, Darryl J. De Ruiter, John Hawks, Lee R. Berger

Faculty Publications

Prior to the recovery of Homo naledi from the Dinaledi Chamber of the Rising Star Cave system, the Middle Pleistocene fossil record in Africa was particularly sparse. With the large sample size now available from Dinaledi, the opportunity exists to reassess taxonomically ambiguous teeth unearthed at the nearby site of Sterkfontein. Teeth recovered from Lincoln Cave South and area L/63 at Sterkfontein have been considered ‘most probably Homo ergaster’ and ‘perhaps Archaic Homo sapiens’, respectively. Given the similarities shared between Lincoln Cave, area L/63, and the Dinaledi Chamber with regard to climatic/geologic depositional context and age, two teeth from the …

The Power Of Prosecutors, Jeffrey Bellin

Faculty Publications

One of the predominant themes in the criminal justice literature is that prosecutors dominate the justice system. Over seventy-five years ago, Attorney General Robert Jackson famously proclaimed that the “prosecutor has more control over life, liberty, and reputation than any other person in America.” In one of the most cited law review articles of all time, Bill Stuntz added that prosecutors—not legislators, judges, or police—“are the criminal justice system’s real lawmakers.” And an unchallenged modern consensus holds that prosecutors “rule the criminal justice system.”

This Article applies a critical lens to longstanding claims of prosecutorial preeminence. It reveals a curious …

An Organizational Account Of State Standing, Katherine Mims Crocker

Faculty Publications

Again and again in regard to recent high-profile disputes, the legal community has tied itself in knots over questions about when state plaintiffs should have standing to sue in federal court, especially in cases where they seek to sue federal-government defendants. Lawsuits challenging everything from the Bush administration’s environmental policies to the Obama administration’s immigration actions to the Trump administration’s travel bans have become mired in tricky and technical questions about whether state plaintiffs belonged in federal court.

Should state standing cause so much controversy and confusion? This Essay argues that state plaintiffs are far more like at least one …

From Trash To Treasure: The Impact Of Consumer Perception Of Bio-Waste Products In Closed-Loop Supply Chains, Ivan Russo, Ilenia Confente, Daniele Scarpi, Benjamin T. Hazen

Faculty Publications

Increasing efforts are made to convert waste into new materials for replacing “traditional” ones. In particular urban bio-waste represents a primary source of concern for both government and society. A new type of polyhydroxyalkanoates (PHA) have been very recently developed to convert food waste into a biodegradable multifunctional raw material to help solving the plastic waste problem. However, little is known about consumers' reactions to products made from PHA. Hence this study aims at understanding consumers' intentions to purchase, pay for, and switch to those bio-based products. Both multivariate analyses of variance and mediation analyses are run, addressing product involvement, …

First-Principles Study Of Feo2HX Solid And Melt System At High Pressures: Implications For Ultralow-Velocity Zones, Jie Deng, Bijaya B. Karki, Dipta B. Ghosh, Kanani K.M. Lee

Faculty Publications

Pyrite-type FeO H (P phase) has recently been suggested as a possible alternative to explain ultralow-velocity zones due to its low seismic velocity and high density. Here we report the results on the congruent melting temperature and melt properties of P phase at high pressures from first-principles molecular dynamics simulations. The results show that P phase would likely be melted near the core–mantle boundary. Liquid FeO H has smaller density and smaller bulk sound velocity compared to the isochemical P phase. As such, relatively small amounts of liquid FeO H could account for the observed seismic anomaly of ultralow-velocity zones. …

A Two Decadal (1993-2012) Numerical Assessment Of Sediment Dynamics In The Northern Gulf Of Mexico, Zhengchen Zang, Z. George Xue, Kehui Xu, Samuel J. Bentley, Qin Chen, Eurico J. D'Sa, Qian Ge

Faculty Publications

© 2019 by the authors. We adapted the coupled ocean-sediment transport model to the northern Gulf of Mexico to examine sediment dynamics on seasonal-to-decadal time scales as well as its response to decreased fluvial inputs from the Mississippi-Atchafalaya River. Sediment transport on the shelf exhibited contrasting conditions in a year, with strong westward transport in spring, fall, and winter, and relatively weak eastward transport in summer. Sedimentation rate varied from almost zero on the open shelf to more than 10 cm/year near river mouths. A phase shift in river discharge was detected in 1999 and was associated with the El …

Data-Driven Estimation Of Significant Kinetic Parameters Applied To The Synthesis Of Polyolefins, Santiago D. Salas, Amanda L.T. Brandão, João B.P. Soares, José A. Romagnoli

Faculty Publications

A data-driven strategy for the online estimation of important kinetic parameters was assessed for the copolymerization of ethylene with 1,9-decadiene using a metallocene catalyst at different diene concentrations and reaction temperatures. An initial global sensitivity analysis selected the significant kinetic parameters of the system. The retrospective cost model refinement (RCMR) algorithm was adapted and implemented to estimate the significant kinetic parameters of the model in real time. After verifying stability and robustness, experimental data validated the algorithm performance. Results demonstrate the estimated kinetic parameters converge close to theoretical values without requiring prior knowledge of the polymerization model and the original …

Balanced Parallel Exploration Of Orthogonal Regions, Wyatt Clements, Costas Busch, Limeng Pu, Daniel Smith, Hsiao Chun Wu

Faculty Publications

We consider the use of multiple mobile agents to explore an unknown area. The area is orthogonal, such that all perimeter lines run both vertically and horizontally. The area may consist of unknown rectangular holes which are non-traversable internally. For the sake of analysis, we assume that the area is discretized into N points allowing the agents to move from one point to an adjacent one. Mobile agents communicate through face-to-face communication when in adjacent points. The objective of exploration is to develop an online algorithm that will explore the entire area while reducing the total work of all k …

Message From The Sst 2019 Workshop Chairs, Jan Philipp Steghofer, Nan Niuy, Jin L.C. Guoz, Anas Nash Mahmoudx

Faculty Publications

No abstract provided.

Steadfast Standards Or Fluctuating Fancies? Stability And Change In People’S Mate Criteria Over 27 Months, Carrie A. Bredow, Nicole Hames

Faculty Publications

Although research on mate preferences has been built on the assumption that the criteria people report at one point in time should predict their future partnering behavior, little is known about the temporal stability of people’s standards. Using survey data collected at four time points from 285 originally unmarried individuals, this study examined the rank-order, meanlevel, individual-level and ipsative stability of people’s mate criteria over 27 months. Overall, reported standards exhibited moderate to high baseline stability, with rank-order and ipsative estimates comparable to those reported for personality traits. At the same time, mean- and individual-level analyses revealed small, but significant, …

Quasi-Sovereign Standing, F. Andrew Hessick

Faculty Publications

This essay proceeds in five Parts. Part I describes the three strands of state standing. It focuses particularly on parens patriae standing to assert quasi-sovereign interests. Part II criticizes the parens patriae framework. It argues that states hold quasi-sovereign interests and accordingly should have direct standing to assert them. Part III argues that states should be able to assert these interests against the United States because of the unique role that states play in our federal system. Part IV argues that recognizing state standing to bring these suits is consistent with the separation of powers theories underlying standing doctrine. Part …