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Alpha-1 antitrypsin deficiency and pregnancy complications and birth outcomes: A population-based cohort study in Denmark (open access)

Alpha-1 antitrypsin deficiency and pregnancy complications and birth outcomes: A population-based cohort study in Denmark

Article describes how alpha-1 antitrypsin deficiency (AATD) is related to developing lung and liver disease, but no large-scale studies examine its association with birth outcomes. The authors investigated the risk of pregnancy complications and adverse birth outcomes in mothers and children with AATD.
Date: January 2, 2024
Creator: Orimoloye, Helen T.; He, Di; Li, Tong; Janzen, Carla; Barjaktarevic, Igor; Wang, Xuexia et al.
System: The UNT Digital Library
Preferential Solvation Study of the Synthesized Aldose Reductase Inhibitor (SE415) in the {PEG 400 (1) + Water (2)} Cosolvent Mixture and GastroPlus-Based Prediction (open access)

Preferential Solvation Study of the Synthesized Aldose Reductase Inhibitor (SE415) in the {PEG 400 (1) + Water (2)} Cosolvent Mixture and GastroPlus-Based Prediction

Article is a study highlighting the mechanistic understanding of the dissolution process of SE415 by biocompatible PEG 400 in the (PEG 400 + water) cosolvent mixture using HSPs, Kirkwood–Buff integrals, and thermodynamic functional parameters for solubility.
Date: October 15, 2021
Creator: Hussain, Afzal; Altamimi, Mohammad A.; Afzal, Obaid; Altamimi, Abdulmalik S. A.; Ali, Abuzer; Ali, Amena et al.
System: The UNT Digital Library
Preferential Solvation Study of the Synthesized Aldose Reductase Inhibitor (SE415) in the {PEG 400 (1) + Water (2)} Cosolvent Mixture and GastroPlus-Based Prediction (open access)

Preferential Solvation Study of the Synthesized Aldose Reductase Inhibitor (SE415) in the {PEG 400 (1) + Water (2)} Cosolvent Mixture and GastroPlus-Based Prediction

This article presents evidence that the binary cosolvent system can be a promising approach for enhanced oral absorption in controlling diabetes mellitus (DM) and associated complications in humans.
Date: January 2, 2022
Creator: Hussain, Afzal; Altamimi, Mohammad A.; Afzal, Obaid; Altamimi, Abdulmalik S. A.; Ali, Abuzer; Ali, Amena et al.
System: The UNT Digital Library
Analysis of the Fe 2p XPS for hematite 𝛂 Fe2O3: Consequences of covalent bonding and orbital splittings on multiplet splittings (open access)

Analysis of the Fe 2p XPS for hematite 𝛂 Fe2O3: Consequences of covalent bonding and orbital splittings on multiplet splittings

Article analyzes the origins of the complex Fe 2p X-Ray Photoelectron Spectra (XPS) of hematite (α-Fe₂O₃) and is related to the character of the bonding in this compound. This analysis provides a new and novel view of the reasons for XPS binding energies (BEs) and BE shifts, which deepens the current understanding and interpretation of the physical and chemical significance of the XPS. This article is part of the JCP Special Topic on Oxide Chemistry and Catalysis.
Date: January 2, 2020
Creator: Bagus, Paul S.; Nelin, Connie J.; Brundle, C. R.; Lahiri, N.; Ilton, Eugene S. & Rosso, Kevin M.
System: The UNT Digital Library
Durability of Portland Concrete Containing Polymeric Fillers and Fly Ash (open access)

Durability of Portland Concrete Containing Polymeric Fillers and Fly Ash

Article explores degradation of Portland concrete and finds that the combination of fly ash with polymers provides significantly improved properties.
Date: January 2, 2020
Creator: Brostow, Witold, 1934-; Chetuya, Nonso; Hong, Hee Jae; Gencel, Osman; Menard, Noah & Sayana, Susmitha
System: The UNT Digital Library
Parents’ mobile technology adoption influences on elementary children’s use (open access)

Parents’ mobile technology adoption influences on elementary children’s use

This article identifies 120 parents' intentions to adopt mobile technology and gathers in-depth perceptions about mobile technology adoption with a smaller subset of 13 parents.
Date: January 2, 2018
Creator: Eutsler, Lauren
System: The UNT Digital Library
Targeting the STAT3 singaling pathway in cancer: Role of synthetic and natural inhibitors (open access)

Targeting the STAT3 singaling pathway in cancer: Role of synthetic and natural inhibitors

Article on targeting the STAT3 signaling pathway in cancer and the role of synthetic and natural inhibitors.
Date: January 2, 2014
Creator: Siveen, Kodappully Sivaraman; Sikka, Sakshi; Surana, Rohit; Dai, Xiaoyun; Zhang, Jingwen; Kumar, Alan Prem et al.
System: The UNT Digital Library
Cryogenic thermonuclear fuel implosions on the National Ignition Facility (open access)

Cryogenic thermonuclear fuel implosions on the National Ignition Facility

None
Date: January 2, 2012
Creator: Glenzer, S. H.; Callahan, D.; Mackinnon, A. J.; Kline, J. L.; Grim, G.; Alger, E. T. et al.
System: The UNT Digital Library
Marine methane cycle simulations for the period of early global warming (open access)

Marine methane cycle simulations for the period of early global warming

Geochemical environments, fates, and effects are modeled for methane released into seawater by the decomposition of climate-sensitive clathrates. A contemporary global background cycle is first constructed, within the framework of the Parallel Ocean Program. Input from organics in the upper thermocline is related to oxygen levels, and microbial consumption is parameterized from available rate measurements. Seepage into bottom layers is then superimposed, representing typical seabed fluid flow. The resulting CH{sub 4} distribution is validated against surface saturation ratios, vertical sections, and slope plume studies. Injections of clathrate-derived methane are explored by distributing a small number of point sources around the Arctic continental shelf, where stocks are extensive and susceptible to instability during the first few decades of global warming. Isolated bottom cells are assigned dissolved gas fluxes from porous-media simulation. Given the present bulk removal pattern, methane does not penetrate far from emission sites. Accumulated effects, however, spread to the regional scale following the modeled current system. Both hypoxification and acidification are documented. Sensitivity studies illustrate a potential for material restrictions to broaden the perturbations, since methanotrophic consumers require nutrients and trace metals. When such factors are considered, methane buildup within the Arctic basin is enhanced. However, freshened polar surface …
Date: January 2, 2011
Creator: Elliott, S.; Maltrud, M.; Reagan, M.T.; Moridis, G.J. & Cameron-Smith, P.J.
System: The UNT Digital Library
Characterization of electron clouds in the Cornell Electron Storage Ring Test Accelerator using TE-wave transmission (open access)

Characterization of electron clouds in the Cornell Electron Storage Ring Test Accelerator using TE-wave transmission

A relatively new technique for measuring the electron cloud density in storage rings has been developed and successfully demonstrated [S. De Santis, J.M. Byrd, F. Caspers, A. Krasnykh, T. Kroyer, M.T.F. Pivi, and K.G. Sonnad, Phys. Rev. Lett. 100, 094801 (2008).]. We present the experimental results of a systematic application of this technique at the Cornell Electron Storage Ring Test Accelerator. The technique is based on the phase modulation of the TE mode transmitted in a synchrotron beam pipe caused by the periodic variation of the density of electron plasma. Because of the relatively simple hardware requirements, this method has become increasingly popular and has been since successfully implemented in several machines. While the principles of this technique are straightforward, quantitative derivation of the electron cloud density from the measurement requires consideration of several effects, which we address in detail.
Date: January 2, 2010
Creator: De Santis, S.; Byrd, J. M.; Billing, M.; Palmer, M.; Sikora, J. & Carlson, B.
System: The UNT Digital Library
Locking Lasers to RF in an Ultra Fast FEL (open access)

Locking Lasers to RF in an Ultra Fast FEL

Using a novel, phase-stabilized RF-over-fiber scheme, they transmit 3GHz over 300m with 27fs RMS error in 250kHz bandwidth over 12 hours, and phase lock a laser to enable ultrafast pump-probe experiments. Free-electron lasers (FELs) are capable of producing short-duration (< 10fs), high-energy X-ray pulses for a range of scientific applications. The recently activated Linac Coherent Light Source (LCLS) FEL facility at SLAC will support experiments which require synchronized light pulses for pump-probe schemes. They developed and operated a fiber optic RF transmission system to synchronize lasers to the emitted X-ray pulses, which was used to enable the first pump-probe experiments at the LCLS.
Date: January 2, 2010
Creator: Wilcox, R.; Huang, G.; Doolittle, L.; White, W.; Frisch, J. & Coffee, R.
System: The UNT Digital Library
Phase Stable RF-over-fiber Transmission using Heterodyne Interferometry (open access)

Phase Stable RF-over-fiber Transmission using Heterodyne Interferometry

New scientific applications require phase-stabilized RF distribution to multiple remote locations. These include phased-array radio telescopes and short pulse free electron lasers. RF modulated onto a CW optical carrier and transmitted via fiber is capable of low noise, but commercially available systems aren't long term stable enough for these applications. Typical requirements are for less than 50fs long term temporal stability between receivers, which is 0.05 degrees at 3GHz. Good results have been demonstrated for RF distribution schemes based on transmission of short pulses, but these require specialized free-space optics and high stability mechanical infrastructure. We report a method which uses only standard telecom optical and RF components, and achieves less than 20fs RMS error over 300m of standard single-mode fiber. We demonstrate stable transmission of 3GHz over 300m of fiber with less than 0.017 degree (17fs) RMS phase error. An interferometer measures optical phase delay, providing information to a feed-forward correction of RF phase.
Date: January 2, 2010
Creator: Wilcox, R.; Byrd, J. M.; Doolittle, L.; Huang, G. & Staples, J. W.
System: The UNT Digital Library
Nonuniformity for rotated beam illumination in directly driven heavy-ion fusion (open access)

Nonuniformity for rotated beam illumination in directly driven heavy-ion fusion

A key issue in heavy-ion beam inertial confinement fusion is target interaction, especially implosion symmetry. In this paper the 2D beam irradiation nonuniformity on the surface of a spherical target is studied. This is a first step to studies of 3D dynamical effects on target implosion. So far non-rotated beams have been studied. Because normal incidence may increase Rayleigh-Taylor instabilities, it has been suggested to rotate beams (to increase average uniformity) and hit the target tangentially. The level of beam irradiation uniformity, beam spill and normal incidence is calculated in this paper. In Mathematica the rotated beams are modeled as an annular integrated Gaussian beam. To simplify the chamber geometry, the illumination scheme is not a 4{pi} system, but the beams are arranged on few polar rings around the target. The position of the beam spot rings is efficiently optimized using the analytical model. The number of rings and beams, rotation radii and widths are studied to optimize uniformity and spilled intensity. The results demonstrate that for a 60-beam system on four rings Peak-To-Valley nonuniformities of under 0.5% are possible.
Date: January 2, 2009
Creator: Runge, J. & Logan, B. G.
System: The UNT Digital Library
Statistical mechanics of sum frequency generation spectroscopy for the liquid-vapor interface of dilute aqueous salt solutions (open access)

Statistical mechanics of sum frequency generation spectroscopy for the liquid-vapor interface of dilute aqueous salt solutions

We demonstrate a theoretical description of vibrational sum frequency generation (SFG) at the boundary of aqueous electrolyte solutions. This approach identifies and exploits a simple relationship between SFG lineshapes and the statistics of molecular orientation and electric field. Our computer simulations indicate that orientational averages governing SFG susceptibility do not manifest ion-specific shifts in local electric field, but instead, ion-induced polarization of subsurface layers. Counterbalancing effects are obtained for monovalent anions and cations at the same depth. Ions held at different depths induce an imbalanced polarization, suggesting that ion-specific effects can arise from weak, long ranged influence on solvent organization.
Date: January 2, 2009
Creator: Noah-Vanhoucke, Joyce; Smith, Jared D. & Geissler, Phillip L.
System: The UNT Digital Library
Phase patterns of coupled oscillators with application to wireless communication (open access)

Phase patterns of coupled oscillators with application to wireless communication

Here we study the plausibility of a phase oscillators dynamical model for TDMA in wireless communication networks. We show that emerging patterns of phase locking states between oscillators can eventually oscillate in a round-robin schedule, in a similar way to models of pulse coupled oscillators designed to this end. The results open the door for new communication protocols in a continuous interacting networks of wireless communication devices.
Date: January 2, 2008
Creator: Arenas, A.
System: The UNT Digital Library
SHIELDING REQUIREMENTS FOR NSLS-II. (open access)

SHIELDING REQUIREMENTS FOR NSLS-II.

Brookhaven National Laboratory is in the process of designing a new Electron Synchrotron for scientific research using synchrotron radiation. This facility, called the 'National Synchrotron Light Source II' (NSLS-II), will provide x-ray radiation of ultra-high brightness and exceptional spatial and energy resolution. It will also provide advanced insertion devices, optics, detectors, and robotics, and a suite of scientific instruments designed to maximize the scientific output of the facility. The project scope includes the design, construction, installation, and commissioning of the following accelerators: a 200 MeV linac, a booster accelerator operating from 200 MeV to 3.0 GeV, and the storage ring which stores a maximum of 500 mA current of electrons at an energy of 3.0 GeV. It is planned to operate the facility primarily in a top-off mode, thereby maintaining the maximum variation in stored beam current to < 1%. Because of the very demanding requirements for beam emittance and synchrotron radiation brilliance, the beam life-time is expected to be low, on the order of 2-3 hours. Analysis of the bulk shielding for operating this facility and the input parameters used for this analysis are discussed in this paper. The characteristics of each of the accelerators and their operating modes …
Date: January 2, 2008
Creator: Job, P. K. & Casey, W. R.
System: The UNT Digital Library
Coordination Environments of Highly Charged Cations (Ti, Cr, and Light REE's) in Borosilicate Glass/Melts to 1120C (open access)

Coordination Environments of Highly Charged Cations (Ti, Cr, and Light REE's) in Borosilicate Glass/Melts to 1120C

The local environments around Ti, Cr, and several light rare-earth elements (La, Ce, and Nd) were investigated by in-situ XANES spectroscopy in a number of complex borosilicate glasses and melts (to 1120 C) that are used for nuclear waste storage. Examination of the high-resolution XANES spectra at the Ti K-edge shows that the average coordination of Ti changes from {approx}5 to {approx}4.5. Cr is dominantly trivalent in the melts studied. However, its average coordination is probably lower in the melt (tetrahedral ?) as revealed by the more intense Cr-K pre-edge feature. Ce also changes its average valence from dominantly +4 to +3.5 upon glass melting. These changes are reversible at T{sub g}, the glass transition temperature ({approx}500-550 C for these glasses). In contrast, the local environments of Nd, Pr, and La are unaffected by melting. Therefore, structural reorganization of these borosilicate glass/melts above T{sub g} is variable, not only in terms of valence (as for Ce) but also speciation (Ti and Cr). Both the ability of B to adopt various coordination geometries (triangular and tetrahedral) and the chemical complexity of the glass/melts explain these changes.
Date: January 2, 2007
Creator: Farges, Francois; /Museum Natl. Hist. Natur. /Stanford U., Geo. Environ. Sci.; Brown, Gordon E., Jr. & /Stanford U., Geo. Environ Sci. /SLAC, SSRL
System: The UNT Digital Library
Durability of Silicate Glasses: An Historical Approach (open access)

Durability of Silicate Glasses: An Historical Approach

We present a short review of current theories of glass weathering, including glass dissolution, and hydrolysis of nuclear waste glasses, and leaching of historical glasses from an XAFS perspective. The results of various laboratory leaching experiments at different timescales (30 days to 12 years) are compared with results for historical glasses that were weathered by atmospheric gases and soil waters over 500 to 3000 years. Good agreement is found between laboratory experiments and slowly leached historical glasses, with a strong enrichment of metals at the water/gel interface. Depending on the nature of the transition elements originally dissolved in the melt, increasing elemental distributions are expected to increase with time for a given glass durability context.
Date: January 2, 2007
Creator: Farges, Francois; /Museum Natl. Hist. Natur. /Stanford U., Geo. Environ. Sci.; Etcheverry, Marie-Pierre; U., /Marne la Vallee; Haddi, Amine; U., /Marne la Valle et al.
System: The UNT Digital Library
LONG-TERM CHANGES IN MERCURY CONCENTRATIONS IN FISH FROM THE MIDDLE SAVANNAH RIVER (open access)

LONG-TERM CHANGES IN MERCURY CONCENTRATIONS IN FISH FROM THE MIDDLE SAVANNAH RIVER

Total mercury levels were measured in largemouth bass (Micropterus salmoides), ''sunfishes'' (Lepomis spp)., and ''catfish'' (primarily Ameiurus spp.) from 1971 to 2004 in the middle reaches of the Savannah River, which drains the coastal plain of the southeastern U.S. Mercury levels were highest in 1971 but declined over the next ten years due to the mitigation of point sources of industrial pollution. Mercury levels began to increase in the 1980s as a possible consequence of mercury inputs from tributaries and associated wetlands where mercury concentrations were significantly elevated in water and fish. Mercury levels in Savannah River fish decreased sharply in 2001-2003 coincident with a severe drought in the Savannah River basin, but returned to previous levels in 2004 with the resumption of normal precipitation. Regression models showed that mercury levels in Savannah River fish changed significantly over time and were affected by river discharge. Despite temporal changes, there was little overall difference in Savannah River fish tissue mercury levels between 1971 and 2004.
Date: January 2, 2007
Creator: Paller, M & Bill Littrell, B
System: The UNT Digital Library
New Developments in Charge Transfer Multiplet Calculations: Projection Operations, Mixed-Spin States and pi-Bonding (open access)

New Developments in Charge Transfer Multiplet Calculations: Projection Operations, Mixed-Spin States and pi-Bonding

This paper presents a number of new additions to the charge transfer multiplet calculations as used in the calculation of L edge X-ray absorption spectra of 3d and 4d transition metal systems, both oxides and coordination compounds. The focus of the paper is on the consequences of the optimized spectral simulations for the ground state, where we make use of a recently developed projection technique. This method is also used to develop the concept of a mixed-spin ground state, i.e. a state that is a mixture of a high-spin and low-spin state due to spin-orbit coupling combined with strong covalency. The charge transfer mechanism to describe {pi}-bonding uses the mixing of the metal-to-ligand charge transfer (MLCT) channel in addition to the normal CT channel and allows for the accurate simulation of {pi}-bonding systems, for example cyanides.
Date: January 2, 2007
Creator: de Groot, F.M.F.; U., /Utrecht; Hocking, R.K.; /Stanford U., Chem. Dept.; Piamonteze, C.; /LBL, Berkeley et al.
System: The UNT Digital Library
Plasma Production via Field Ionization (open access)

Plasma Production via Field Ionization

Plasma production via field ionization occurs when an incoming particle beam is sufficiently dense that the electric field associated with the beam ionizes a neutral vapor or gas. Experiments conducted at the Stanford Linear Accelerator Center explore the threshold conditions necessary to induce field ionization by an electron beam in a neutral lithium vapor. By independently varying the transverse beam size, number of electrons per bunch or bunch length, the radial component of the electric field is controlled to be above or below the threshold for field ionization. Additional experiments ionized neutral xenon and neutral nitric oxide by varying the incoming beam's bunch length. A self-ionized plasma is an essential step for the viability of plasma-based accelerators for future high-energy experiments.
Date: January 2, 2007
Creator: O'Connell, C. L.; Barnes, C. D.; Decker, F.; Hogan, M. J.; Iverson, R.; Krejcik, P. et al.
System: The UNT Digital Library
USING STATISTICAL PROCESS CONTROL TO MONITOR RADIOACTIVE WASTE CHARACTERIZATION AT A RADIOACTIVE FACILITY (open access)

USING STATISTICAL PROCESS CONTROL TO MONITOR RADIOACTIVE WASTE CHARACTERIZATION AT A RADIOACTIVE FACILITY

Two facilities for storing spent nuclear fuel underwater at the Hanford site in southeastern Washington State are being removed from service, decommissioned, and prepared for eventual demolition. The fuel-storage facilities consist of two separate basins called K East (KE) and K West (KW) that are large subsurface concrete pools filled with water, with a containment structure over each. The basins presently contain sludge, debris, and equipment that have accumulated over the years. The spent fuel has been removed from the basins. The process for removing the remaining sludge, equipment, and structure has been initiated for the basins. Ongoing removal operations generate solid waste that is being treated as required, and then disposed. The waste, equipment and building structures must be characterized to properly manage, ship, treat (if necessary), and dispose as radioactive waste. As the work progresses, it is expected that radiological conditions in each basin may change as radioactive materials are being moved within and between the basins. It is imperative that these changing conditions be monitored so that radioactive characterization of waste is adjusted as necessary.
Date: January 2, 2007
Creator: Westcott, J. L.; Jochen, R. M. & Prevette, S. S.
System: The UNT Digital Library
Water-Steel Canister Interaction and H2 Gas Pressure Buildup in aNuclear Waste Repository (open access)

Water-Steel Canister Interaction and H2 Gas Pressure Buildup in aNuclear Waste Repository

Corrosion of steel canisters, stored in a repository forspent fuel and high-level waste, leads to hydrogen gas generation in thebackfilled emplacement tunnels, which may significantly affect long-termrepository safety. Previous modeling studies used a constant H2generation rate. However, iron corrosion and H2 generation rates varywith time, depending on factors such as water chemistry, wateravailability, and water contact area. To account for these factors andfeedback mechanisms, we developed a chemistry model related to ironcorrosion, coupled with two-phase (liquid and gas) flow phenomena thatare driven by gas pressure buildup and water consumption. Resultsindicate that if H2 generation rates are dynamically calculated based ona chemistry model, the degree and extent of gas pressure buildup are muchsmaller compared to a simulation in which the coupling between flow andreactive transport mechansism is neglected.
Date: January 2, 2007
Creator: Xu, Tianfu; Senger, Rainer & Finstele, Stefan
System: The UNT Digital Library
Chemical Force Microscopy of Chemical and Biological Interactions (open access)

Chemical Force Microscopy of Chemical and Biological Interactions

Interactions between chemical functionalities define outcomes of the vast majority of important events in chemistry, biology and materials science. Chemical Force Microscopy (CFM)--a technique that uses direct chemical functionalization of AFM probes with specific functionalities--allows researchers to investigate these important interactions directly. We review the basic principles of CFM, some examples of its application, and theoretical models that provide the basis for understanding the experimental results. We also emphasize application of modern kinetic theory of non-covalent interactions strength to the analysis of CFM data.
Date: January 2, 2006
Creator: Noy, A
System: The UNT Digital Library