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Full-Text Articles in Physical Sciences and Mathematics

Fermi Questions, Question 1: Air Pressure On Waves; Question 2: Weight Of Toner, Larry Weinstein Mar 2018

Fermi Questions, Question 1: Air Pressure On Waves; Question 2: Weight Of Toner, Larry Weinstein

Physics Faculty Publications

The article presents questions on the difference in air pressure at the crest and trough of ocean waves because of the Bernoulli effect and the difference in weight between a 100-page printed document and 100 blank pages.


Electroosmotic Flow Of Viscoelastic Fluid In A Nanoslit, Lanju Mei, Hongna Zhang, Hongxia Meng, Shizhi Qian Mar 2018

Electroosmotic Flow Of Viscoelastic Fluid In A Nanoslit, Lanju Mei, Hongna Zhang, Hongxia Meng, Shizhi Qian

Mechanical & Aerospace Engineering Faculty Publications

The electroosmotic flow (EOF) of viscoelastic fluid in a long nanoslit is numerically studied to investigate the rheological property effect of Linear Phan-Thien-Tanner (LPTT) fluid on the fully developed EOF. The non-linear Poisson-Nernst-Planck equations governing the electric potential and the ionic concentration distribution within the channel are adopted to take into account the effect of the electrical double layer (EDL), including the EDL overlap. When the EDL is not overlapped, the velocity profiles for both Newtonian and viscoelastic fluids are plug-like and increase sharply near the charged wall. The velocity profile resembles that of pressure-driven flow when the EDL is …


Bandgap Profiling In Cigs Solar Cells Via Valence Electron Energy-Loss Spectroscopy, Julia I. Deitz, Shankar Karki, Sylvain X. Marsillac, Tyler J. Grassman Mar 2018

Bandgap Profiling In Cigs Solar Cells Via Valence Electron Energy-Loss Spectroscopy, Julia I. Deitz, Shankar Karki, Sylvain X. Marsillac, Tyler J. Grassman

Electrical & Computer Engineering Faculty Publications

A robust, reproducible method for the extraction of relative bandgap trends from scanning transmission electron microscopy (STEM) based electron energy-loss spectroscopy (EELS) is described. The effectiveness of the approach is demonstrated by profiling the bandgap through a CuIn1-xGaxSe2 solar cell that possesses intentional Ga/(In + Ga) composition variation. The EELS-determined bandgap profile is compared to the nominal profile calculated from compositional data collected via STEM-based energy dispersive X-ray spectroscopy. The EELS based profile is found to closely track the calculated bandgap trends, with only a small, fixed offset difference. This method, which is particularly advantageous …


Sea Level Rise Moving Faster Than Scientists Initially Thought, Noell Saunders Feb 2018

Sea Level Rise Moving Faster Than Scientists Initially Thought, Noell Saunders

News Items

No abstract provided.


Odu-Led St. Vincent Workshop Explored Ocean's Role In Caribbean-Based U.N. Sustainable Development Initiative, News @ Odu Feb 2018

Odu-Led St. Vincent Workshop Explored Ocean's Role In Caribbean-Based U.N. Sustainable Development Initiative, News @ Odu

News Items

No abstract provided.


An Analysis Of The Efficacy Of Climate Challenge, Nicholas Barnes, Leslie Cook, Brandon Sharpton Feb 2018

An Analysis Of The Efficacy Of Climate Challenge, Nicholas Barnes, Leslie Cook, Brandon Sharpton

Undergraduate Research Symposium

The temperature in our atmosphere is steadily rising; therefore, we need a method of communicating climate risk that educates and motivates people faster than the rising sea level. Our presentation analyzes the communicative effectiveness of Climate Challenge, a game created for this purpose. We will also analyze and utilize prior research of climate change games and serious games. We gathered participants for our research using convenience and snowball sampling. We conducted a pre-test survey and post-test interview, along with a screencast-recorded playthrough of Climate Challenge. After the research session we used grounded theory and inductive thematic analysis to …


Scientific And Technical Advisory Committee Review Of The Chesapeake Bay Program Partnership’S Climate Change Assessment Framework And Programmatic Integration And Response Efforts, Maria Hermann, Scott Doney, Tal Ezer, Keryn Gedan, Philip Morefield, Barbara Muhling, Douglas Pirhalla, Stephen Shaw Feb 2018

Scientific And Technical Advisory Committee Review Of The Chesapeake Bay Program Partnership’S Climate Change Assessment Framework And Programmatic Integration And Response Efforts, Maria Hermann, Scott Doney, Tal Ezer, Keryn Gedan, Philip Morefield, Barbara Muhling, Douglas Pirhalla, Stephen Shaw

CCPO Publications

[From the Executive Summary] The following report presents a synthesis of reviewer responses from the Scientific and Technical Advisory Committee’s (STAC) panel on the Chesapeake Bay Program Partnership’s Climate Change Assessment Framework (CCAF) and Programmatic Integration and Response Efforts. The enclosed findings and recommendations are in response to the 16 questions delivered to the panel (Appendix A).

In summary, given the current state of knowledge, the combination of using climate model projections and downscaling provides an acceptable baseline for estimating changing climate conditions for the Chesapeake Bay, and the panel finds the CCAF approach to be fundamentally sound. However, the …


Effects Of Projected Changes In Wind, Atmospheric Temperature, And Freshwater Inflow On The Ross Sea, Michael S. Dinniman, John M. Klinck, Eileen E. Hofmann, Walker O. Smith Jr. Feb 2018

Effects Of Projected Changes In Wind, Atmospheric Temperature, And Freshwater Inflow On The Ross Sea, Michael S. Dinniman, John M. Klinck, Eileen E. Hofmann, Walker O. Smith Jr.

CCPO Publications

A 5-km horizontal resolution regional ocean-sea ice-ice shelf model of the Ross Sea is used to examine the effects of changes in wind strength, air temperature, and increased meltwater input on the formation of high-salinity shelf water (HSSW), on-shelf transport and vertical mixing of Circumpolar Deep Water (CDW) and its transformation into modified CDW (MCDW), and basal melt of the Ross Ice Shelf (RIS). A 20% increase in wind speed, with no other atmospheric changes, reduced summer sea ice minimum area by 20%, opposite the observed trend of the past three decades. Increased winds with spatially uniform, reduced atmospheric temperatures …


Light-Nuclei Spectra From Chiral Dynamics, M. Piarulli, A. Baroni, L. Girlanda, A. Kievsky, A. Lovato, Ewing Lusk, L. E. Marcucci, Steven C. Pieper, R. Schiavilla, M, Viviani, R. B. Wiringa Feb 2018

Light-Nuclei Spectra From Chiral Dynamics, M. Piarulli, A. Baroni, L. Girlanda, A. Kievsky, A. Lovato, Ewing Lusk, L. E. Marcucci, Steven C. Pieper, R. Schiavilla, M, Viviani, R. B. Wiringa

Physics Faculty Publications

In recent years local chiral interactions have been derived and implemented in quantum Monte Carlo methods in order to test to what extent the chiral effective field theory framework impacts our knowledge of few- and many-body systems. In this Letter, we present Green's function Monte Carlo calculations of light nuclei based on the family of local two-body interactions presented by our group in a previous paper in conjunction with chiral three-body interactions fitted to bound- and scattering-state observables in the three-nucleon sector. These interactions include Δ intermediate states in their two-pion-exchange components. We obtain predictions for the energy levels and …


Double K-S(0) Photoproduction Off The Proton At Clas, S. Chandavar, J. T. Goetz, K. Hicks, D. Keller, M. C. Kunkel, M. Paolone, D. P. Weygand, K. P. Adhikari, S. Adhikari, Z. Akbar, G. Charles, G. Gavalian, M. Khachatryan, A. Klein, Y. Prok, J. Zhang, Z. W. Zhao, The Clas Collaboration Feb 2018

Double K-S(0) Photoproduction Off The Proton At Clas, S. Chandavar, J. T. Goetz, K. Hicks, D. Keller, M. C. Kunkel, M. Paolone, D. P. Weygand, K. P. Adhikari, S. Adhikari, Z. Akbar, G. Charles, G. Gavalian, M. Khachatryan, A. Klein, Y. Prok, J. Zhang, Z. W. Zhao, The Clas Collaboration

Physics Faculty Publications

The f0(1500) meson resonance is one of several contenders to have significant mixing with the lightest glueball. This resonance is well established from several previous experiments. Here we present the first photoproduction data for the f0(1500) via decay into the K-S(0) K-S(0) channel using the CLAS detector. The reaction γp → fJp → K-S(0) K-S(0) p,where J = 0,2, was measured with photon energies from 2.7–5.1 GeV. A clear peak is seen at 1500 MeV in the background subtracted invariant mass spectra of the two kaons. This is enhanced if the measured four-momentum transfer …


Inactivation Of Myeloma Cancer Cells By Helium And Argon Plasma Jets: The Effect Comparison And The Key Reactive Species, Zeyu Chen, Qingjie Cui, Chen Chen, Dehui Xu, Dingxin Liu, H. L. Chen, Michael G. Kong Feb 2018

Inactivation Of Myeloma Cancer Cells By Helium And Argon Plasma Jets: The Effect Comparison And The Key Reactive Species, Zeyu Chen, Qingjie Cui, Chen Chen, Dehui Xu, Dingxin Liu, H. L. Chen, Michael G. Kong

Bioelectrics Publications

In plasma cancer therapy, the inactivation of cancer cells under plasma treatment is closely related to the reactive oxygen and nitrogen species (RONS) induced by plasmas. Quantitative study on the plasma-induced RONS that related to cancer cells apoptosis is critical for advancing the research of plasma cancer therapy. In this paper, the effects of several reactive species on the inactivation of LP-1 myeloma cancer cells are comparatively studied with variable working gas composition, surrounding gas composition, and discharge power. The results show that helium plasma jet has a higher cell inactivation efficiency than argon plasma jet under the same discharge …


New Approaches To Model Simulated Spatio-Temporal Moran's Index, Nhan Bu, Jennifer Lorio, Norou Diawara, Kumar Das, Lance Waller Feb 2018

New Approaches To Model Simulated Spatio-Temporal Moran's Index, Nhan Bu, Jennifer Lorio, Norou Diawara, Kumar Das, Lance Waller

Mathematics & Statistics Faculty Publications

The Moran's index is a statistic that measures spatial autocorrelation; it quantifies the degree of dispersion (or clustering) of objects in space. However, when investigating data over a general area, a single global Moran statistic may not give a sufficient summary of the spread, behavior, features or latent surfaces shared by neighboring areas; rather, by partitioning the area and taking the Moran statistic of each divided subareas, we can discover patterns of the local neighbors not otherwise apparent. In this paper, we present a simulation experiment where the local Moran values are computed and a time variable is added to …


Odu Colleges Prepare To Collaborate On Second Arctic Research Expedition, Roger Njunge Jan 2018

Odu Colleges Prepare To Collaborate On Second Arctic Research Expedition, Roger Njunge

News Items

No abstract provided.


Civil Engineering Ph.D. Student Puts Virginia Sea Grant Graduate Fellowship To Work On Living Shorelines, Keith Pierce Jan 2018

Civil Engineering Ph.D. Student Puts Virginia Sea Grant Graduate Fellowship To Work On Living Shorelines, Keith Pierce

News Items

No abstract provided.


2017 Costliest Year Ever For Weather-Related Disasters, Betsy Hnath Jan 2018

2017 Costliest Year Ever For Weather-Related Disasters, Betsy Hnath

News Items

No abstract provided.


Editorial-The 8th International Workshop On Modeling The Ocean (Iwmo 2016) In Bologna, Italy, June 7-10, 2016, Tal Ezer, Lie-Yauw Oey, Huijie Xue, Marco Zavatarelli, Gianmaria Sannino, Ricardo De Camargo Jan 2018

Editorial-The 8th International Workshop On Modeling The Ocean (Iwmo 2016) In Bologna, Italy, June 7-10, 2016, Tal Ezer, Lie-Yauw Oey, Huijie Xue, Marco Zavatarelli, Gianmaria Sannino, Ricardo De Camargo

CCPO Publications

The 8th International Workshop on Modeling the Ocean (IWMO 2016) was held on June 7–10, 2016, at one of the oldest universities in Europe—the University of Bologna in Italy (founded 1088 A.D.). The workshop returned to Europe for the second time (the other European IWMO was held in Norway in 2013; Berntsen et al. 2014). Since the establishment of the IWMO in 2009 (Oey et al. 2010a, b), meetings were held four times in Asia, two times in Europe, two times in North America, one time in Australia, and for the 10th anniversary of IWMO, the 2018’s meeting will be …


Question 1: Throwing Out Energy; Question 2: Blood Pressure, Larry Weinstein Jan 2018

Question 1: Throwing Out Energy; Question 2: Blood Pressure, Larry Weinstein

Physics Faculty Publications

The article presents two questions on the amount of energy wasted by Americans whenever they throw out unused ice in their drinks, and why is blood pressure measured on the upper arm.


Tuning Vortex Fluctuations And The Resistive Transition In Superconducting Films With A Thin Overlayer, Alex Gurevich Jan 2018

Tuning Vortex Fluctuations And The Resistive Transition In Superconducting Films With A Thin Overlayer, Alex Gurevich

Physics Faculty Publications

It is shown that the temperature of the resistive transition Tr of a superconducting film can be increased by a thin superconducting or normal overlayer. For instance, deposition of a highly conductive thin overlayer onto a dirty superconducting film can give rise to an “antiproximity effect,” which manifests itself in an initial increase of Tr (d2) with the overlayer thickness d2 followed by a decrease of Tr (d2)at larger d2. Such a nonmonotonic thickness dependence of Tr (d2) results from the interplay of the …


Room Temperature Measurements Of Higher Order Modes For The Sps Prototype Rf Dipole Crabbing Cavity, Subashini De Silva, P. Berrutti, Jean R. Delayen, N. A. Huque, Hyekyoung Park Jan 2018

Room Temperature Measurements Of Higher Order Modes For The Sps Prototype Rf Dipole Crabbing Cavity, Subashini De Silva, P. Berrutti, Jean R. Delayen, N. A. Huque, Hyekyoung Park

Physics Faculty Publications

LHC High Luminosity Upgrade will be developing two local crabbing systems to increase the luminosity of the colliding bunches at the ATLAS and CMS experiments. One of the crabbing systems uses the rf-dipole cavity design that will be crabbing the beam in the horizontal plane. The fully integrated crabbing cavity has two higher order mode couplers in damping those excited modes. Currently two sets of HOM couplers have been fabricated at Jefferson Lab for prototyping and testing with the LARP crabbing cavities. This paper presents the measurements of the higher order modes with the prototype HOM couplers carried out at …


Software Intrusion Detection Evaluation System: A Cost-Based Evaluation Of Intrusion Detection Capability, Agbotiname L. Imoize, Taiwo Oyedare, Michael E. Otuokere, Sachin Shetty Jan 2018

Software Intrusion Detection Evaluation System: A Cost-Based Evaluation Of Intrusion Detection Capability, Agbotiname L. Imoize, Taiwo Oyedare, Michael E. Otuokere, Sachin Shetty

VMASC Publications

In this paper, we consider a cost-based extension of intrusion detection capability (CID). An objective metric motivated by information theory is presented and based on this formulation; a package for computing the intrusion detection capability of intrusion detection system (IDS), given certain input parameters is developed using Java. In order to determine the expected cost at each IDS operating point, the decision tree method of analysis is employed, and plots of expected cost and intrusion detection capability against false positive rate were generated. The point of intersection between the maximum intrusion detection capability and the expected cost is selected as …


A Reliable Data Provenance And Privacy Preservation Architecture For Business-Driven Cyber-Physical Systems Using Blockchain, Xueping Liang, Sachin Shetty, Deepak K. Tosh, Juan Zhao, Danyi Li, Jihong Liu Jan 2018

A Reliable Data Provenance And Privacy Preservation Architecture For Business-Driven Cyber-Physical Systems Using Blockchain, Xueping Liang, Sachin Shetty, Deepak K. Tosh, Juan Zhao, Danyi Li, Jihong Liu

VMASC Publications

Cyber-physical systems (CPS) including power systems, transportation, industrial control systems, etc. support both advanced control and communications among system components. Frequent data operations could introduce random failures and malicious attacks or even bring down the whole system. The dependency on a central authority increases the risk of single point of failure. To establish an immutable data provenance scheme for CPS, the authors adopt blockchain and propose a decentralized architecture to assure data integrity. In business-driven CPS, end users are required to share their personal information with multiple third parties. To prevent data leakage and preserve user privacy, the authors isolate …


Introduction: Metrics, Modeling And Simulation For Cyber Physical Systems, Barry Ezell, Luanne Burns Jan 2018

Introduction: Metrics, Modeling And Simulation For Cyber Physical Systems, Barry Ezell, Luanne Burns

VMASC Publications

[Introduction] In recent years, there has been a massive increase in cyber crime. Cyber breeches have become ubiquitous. The US government is attempting to adapt through legislation and policy. For instance, business in the defense industrial base must be in compliance of NIST 80-71 by 31 December 2017. Insurance companies as well are beginning to build actuaries on cyber risk. Along with NIST, there are many cyber frameworks that exist, each with their own following. Recently, companies have sought mapping from one framework to another but this is imperfect solution because some frameworks are exclusively technical control measures with very …


Introduction - Syllabus, C. Ariel Pinto Jan 2018

Introduction - Syllabus, C. Ariel Pinto

Module 1: Fundamentals of Cybersecurity Risk Management

Cybersecurity risk management is a necessary tool for decision making for all management levels from tactical to strategic and creating a common understanding between people from diverse domains or having different priorities. This course adopts a multidisciplinary perspective. It creates a common understanding of risk for a diverse set of students which are coming from different disciplines such as technical, social, economics, law, and politics to remove communication barriers between strategic, operational, and tactical level decision makers.

The course covers related government and industry regulations and standards along with best practices frequently used to assess, analyze and manage cyber risks, …


Switching Mechanism In The B-1revtilted Phase Of Bent-Core Liquid Crystals, Carlos J. García-Cervera, Tiziana Giorgi, Sookyung Joo, Xin Yang Lu Jan 2018

Switching Mechanism In The B-1revtilted Phase Of Bent-Core Liquid Crystals, Carlos J. García-Cervera, Tiziana Giorgi, Sookyung Joo, Xin Yang Lu

Mathematics & Statistics Faculty Publications

The B1RevTilted is a uniformly smectic tilted columnar phase in which the macroscopic polarization can be reorientated via electric field. To study the effects on the reorientation mechanism of the various physical parameters, we analyze a local, and a non-local Landau-de Gennes-type energy functional. For the case of large columnar samples, we show that both energies give the same qualitative behavior, with a relevant role played by the terms that describe the interaction between polarization and nematic directors. We also obtain existence of the L2-gradient flow in metric spaces for the full local energy.


The Spatial Context Of “Winning” In Mpa Network Design: Location Matters, Andrew S. Kough, Claire B. Paris, Mark J. Butler Iv Jan 2018

The Spatial Context Of “Winning” In Mpa Network Design: Location Matters, Andrew S. Kough, Claire B. Paris, Mark J. Butler Iv

Biological Sciences Faculty Publications

(First paragraph) Chollett et al. (2017) make the case that a local network of marine protected areas (MPAs) enhances fisheries for Caribbean spiny lobster (Panulirus argus) off the coast of Honduras. However, their simulation focused on one ecoregion where self-recruitment is predicted to be among the highest in the Caribbean (Cowen, Paris, & Srinivasan, 2006). The shallow banks and scattered cays of the Honduran-Nicaraguan Rise, separating the Cayman and Colombian basins, create an obstacle to the powerful southern Caribbean jet (Richardson, 2005), fostering an ideal location for topographically steered eddies and larval retention. Local management,whether based on traditional …


High Frequency Temperature Variability Reduces The Risk Of Coral Bleaching, Aryan Safaie, Nyssa J. Silbiger, Timothy R. Mcclanahan, Geno Pawlak, Daniel J. Barshis, James L. Hench, Gareth J. Williams, Kristen A. Davis Jan 2018

High Frequency Temperature Variability Reduces The Risk Of Coral Bleaching, Aryan Safaie, Nyssa J. Silbiger, Timothy R. Mcclanahan, Geno Pawlak, Daniel J. Barshis, James L. Hench, Gareth J. Williams, Kristen A. Davis

Biological Sciences Faculty Publications

Coral bleaching is the detrimental expulsion of algal symbionts from their cnidarian hosts, and predominantly occurs when corals are exposed to thermal stress. The incidence and severity of bleaching is often spatially heterogeneous within reef-scales (km), and is therefore not predictable using conventional remote sensing products. Here, we systematically assess the relationship between in situ measurements of 20 environmental variables, along with seven remotely sensed SST thermal stress metrics, and 81 observed bleaching events at coral reef locations spanning five major reef regions globally. We find that high-frequency temperature variability (i.e., daily temperature range) was the most influential factor in …


Integrated Ocean, Earth, And Atmospheric Observations For Resilience Planning In Hampton Roads, Virginia, Jon Derek Loftis, Molly Mitchell, Larry Atkinson, Ben Hamlington, Tom Allen, David Forrest, Teresa Updyke, Navid Tahvildari, David Bekaert, Mark Bushnell Jan 2018

Integrated Ocean, Earth, And Atmospheric Observations For Resilience Planning In Hampton Roads, Virginia, Jon Derek Loftis, Molly Mitchell, Larry Atkinson, Ben Hamlington, Tom Allen, David Forrest, Teresa Updyke, Navid Tahvildari, David Bekaert, Mark Bushnell

CCPO Publications

Building flood resilience in coastal communities requires a precise understanding of the temporal and spatial scales of inundation and the ability to detect and predict changes in flooding. In Hampton Roads, the Intergovernmental Pilot Project’s Scientific Advisory Committee recommended an integrated network of ocean, earth, and atmospheric data collection from both private and public sector organizations that engage in active scientific monitoring and observing. Since its establishment, the network has grown to include monitoring of water levels, land subsidence, wave measurements, current measurements, and atmospheric conditions. High-resolution land elevation and land cover data sets have also been developed. These products …


Global Sea-Level Budget 1993-Present, Wcrp Global Sea Level Budget Group, Benjamin Hamlington Jan 2018

Global Sea-Level Budget 1993-Present, Wcrp Global Sea Level Budget Group, Benjamin Hamlington

CCPO Publications

Global mean sea level is an integral of changes occurring in the climate system in response to unforced climate variability as well as natural and anthropogenic forcing factors. Its temporal evolution allows changes (e.g.,acceleration) to be detected in one or more components. Study of the sea-level budget provides constraints on missing or poorly known contributions, such as the unsurveyed deep ocean or the still uncertain land water component. In the context of the World Climate Research Programme Grand Challenge entitled "Regional Sea Level and Coastal Impacts", an international effort involving the sea-level community worldwide has been recently initiated with the …


Analyzing The Spectral Energy Cascade In Turbulent Channel Flow, João Rodrigo Andrade, Ramon Silva Martins, Gilmar Mompean, Laurent Thais, Thomas B. Gatski Jan 2018

Analyzing The Spectral Energy Cascade In Turbulent Channel Flow, João Rodrigo Andrade, Ramon Silva Martins, Gilmar Mompean, Laurent Thais, Thomas B. Gatski

CCPO Publications

An analysis of the spectral turbulent kinetic energy budget in a fully developed turbulent plane channel flow is performed. Direct numerical simulation data are evaluated at friction Reynolds numbers Reτ of 180 and 1000. The analysis is focused on the influence of the Reynolds number on the spectral cascade of energy and the corresponding energy cascade in physical space in the presence of inhomogeneity and anisotropy. The turbulent kinetic energy distribution is compared for both Reynolds numbers, and the relevant characteristics of the energy transfer process in a wall-bounded turbulent flow are described. Differences in energy cascade are noted …


Volcanogenic Pseudo-Fossils From The ~3.48 Ga Dresser Formation, Pilbara, Western Australia, David Wacey, Nora Noffke, Martin Saunders, Paul Guagliardo, David M. Pyle Jan 2018

Volcanogenic Pseudo-Fossils From The ~3.48 Ga Dresser Formation, Pilbara, Western Australia, David Wacey, Nora Noffke, Martin Saunders, Paul Guagliardo, David M. Pyle

OES Faculty Publications

The ~ 3.48 billion-year-old Dresser Formation, Pilbara Craton, Western Australia, is a key geological unit for the study of Earth's earliest life and the habitats it occupied. Here, we describe a new suite of spheroidal to lenticular microstructures that morphologically resemble some previously reported Archean microfossils. Correlative microscopy shows that these objects have a size distribution, wall ultrastructure, and chemistry that are incompatible with a microfossil origin and instead are interpreted as pyritized and silicified fragments of vesicular volcanic glass. Organic kerogenous material is associated with much of the altered volcanic glass; variable quantities of organic carbon line or fill …