Publications by authors named "Richard Weber"

235 Publications

Allergy to oak pollen in North America.

Allergy Asthma Proc 2021 01;42(1):43-54

ALK, Bedminster, New Jersey.

Oak pollen is an important allergen in North America. The genus Quercus (oak) belongs to the family Fagaceae under the order Fagales. The objective of this article was to narratively review the oak pollen season, clinical and epidemiologic aspects of allergy to oak pollen, oak taxonomy, and oak allergen cross-reactivity, with a focus on the North American perspective. A PubMed literature review (no limits) was conducted. Publications related to oak pollen, oak-related allergic rhinitis with or without conjunctivitis, and oak-related allergic asthma were selected for review. Oak species are common throughout the United States and contribute up to 50% to overall atmospheric pollen loads. Mean peak oak pollen counts can reach >2000 grains/m³. The start of the oak pollen season generally corresponds to the seasonal shift from winter to spring based on latitude and elevation, and may begin as early as mid February. The duration of the season can last > 100 days and, in general, is longer at lower latitudes. In the United States, ∼30% of individuals with allergy are sensitized to oak. The oak pollen season correlates with increased allergic rhinitis symptom-relieving medication use and asthma-related emergency department visits or hospitalizations. Oak falls within the birch homologous group. Extensive immunologic cross-reactivity has been demonstrated between oak pollen and birch pollen allergens, and, more specifically, their major allergens Que a 1 and Bet v 1. The cross-reactivity between oak and birch has implications for allergy immunotherapy (AIT) because guidelines suggest selecting one representative allergen within a homologous group for AIT, a principle that would apply to oak. Allergy to oak pollen is common in North America and has a substantial clinical impact. Oak pollen allergens are cross-reactive with birch pollen allergens, which may have implications for AIT.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2500/aap.2021.42.200089DOI Listing
January 2021

Vulnerability analysis of water distribution networks to accidental pipe burst.

Water Res 2020 Oct 13;184:116178. Epub 2020 Jul 13.

Budapest University of Technology and Economics, Faculty of Mechanical Engineering,Department of Hydrodynamic Systems, Hungary. Electronic address:

Even the best-maintained water distribution network (WDN) might suffer pipe bursts occasionally, and the utility company must reconstruct the damaged sections of the system. The affected area must be segregated by closing the corresponding isolation valves; as a result, the required amount of drinking water might not be available. This paper explores the behaviour and topology of segments, especially their criticality from the viewpoint of the whole system. A novel, objective, dimensionless, segment-based quantity is proposed to evaluate the vulnerability of both the segments and the whole WDN against a single, incidental pipe break, computed as the product of the probability of failure within the segment and the amount of unserved consumption. 27 comprehensive real-life WDNs have been examined by means of the new metric and with the help of complex network theory, exploiting the concept of the degree distribution and topology-based structural properties (e.g. network diameter, clustering coefficient). It was found that metrics based purely on topology suggest different network behaviour as vulnerability analysis, which also includes the hydraulics. The investigation of the global network vulnerabilities has revealed several critically exposed systems, and the local distributions unveiled new properties of WDNs in the case of a random pipe break.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.watres.2020.116178DOI Listing
October 2020

In Situ High-Temperature Synchrotron Diffraction Studies of (Fe,Cr,Al)O Spinels.

Inorg Chem 2020 May 22;59(9):5949-5957. Epub 2020 Apr 22.

Peter A. Rock Thermochemistry Laboratory, University of California-Davis (UC Davis), Davis, California 95616, United States.

The modeling of a loss-of-coolant-accident scenario involving nuclear fuels with FeCrAl cladding materials in consideration to replace a Zircaloy requires knowledge of the thermodynamics of oxidized structures. At temperatures higher than 1500 °C, oxidation of FeCrAl alloys forms (Fe,Cr,Al)O spinels. In situ high-energy X-ray diffraction in a conical nozzle levitator installed at beamline 6-ID-D of the APS was used to study the structural evolution of the oxides as a function of the temperature. Single-phase (spinel) and multiphase (spinel-corundum-FeAlO) regions are mapped as a function of the temperature for three different compositions of FeCrAl oxidation products. The thermal expansion coefficients and cation distribution in the spinel structure have been refined. The temperature at which complete melting of the fuel cladding is expected has been determined by the liquidus temperatures of the oxidized products to be between 1657 and 1834 °C in a 20% O/Ar atmosphere using the cooling trace method. The liquidus temperature increases with increasing Al and Cr content in the spinel phase.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.inorgchem.9b03726DOI Listing
May 2020

The impact of weather and climate on pollen concentrations in Denver, Colorado, 2010-2018.

Ann Allergy Asthma Immunol 2019 11 8;123(5):494-502.e4. Epub 2019 Aug 8.

University of Colorado School of Medicine, Aurora, Colorado; Colorado School of Public Health, Aurora, Colorado. Electronic address:

Background: Increasing evidence indicates that climate change is affecting the timing of pollen season and concentrations of allergenic pollens. To date, pollen trends and their associations with meteorological variables have not been studied in most of the United States.

Objective: The purpose of this study was to investigate the effects of weather and climate on pollen concentrations and pollen season timing in Denver, Colorado.

Methods: We retrospectively analyzed tree, grass, and weed pollen counts and meteorological variables from 2010-2018 using linear and Poisson regression models.

Results: Pollen season timing did not demonstrate uniform trends from 2010 to 2018. Certain species demonstrated earlier season start dates (linden, oak) or end dates (birch, maple), and others had later end dates (oak, grass). Only a few species demonstrated changes in season duration (linden, oak, maple, birch) and peak date (maple, birch). Pollen concentrations either remained stable or increased over the years. Temperature and carbon dioxide levels increased over the study period, with the exception of decreased temperature in August. Wind speed remained stable or decreased over the study period.

Conclusion: This study illustrates the complex interactions between pollens and meteorology. Meteorological variables associated with climate change do appear to affect allergenic pollens, though the relationship is variable both amongst pollens and from year to year.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2019.08.002DOI Listing
November 2019

Temperature gradients for thermophysical and thermochemical property measurements to 3000 °C for an aerodynamically levitated spheroid.

Rev Sci Instrum 2019 Jan;90(1):015109

Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.

This study examines thermal gradients in ceramic oxide spheroids being aerodynamically levitated in a conical nozzle levitator (CNL) system equipped with a CO laser (10.6 µm wavelength). The CNL system is a versatile piece of equipment that can easily be coupled with advanced thermophysical and thermochemical measuring devices, such as diffraction/scattering (X-ray and neutron), nuclear magnetic resonance, and calorimetry, for the analysis of bulk spheroidal solids and liquids. The thermal gradients of a series of single crystal, polycrystalline solids, and liquid spheroids have been measured spatially in the CNL system, by means of a disappearing filament pyrometer (800-3000 °C) and by X-ray diffraction with reference to an internal standard (Pt: 800-1600 °C). The thermal gradient in a levitated sample being heated by a laser from the top can be minimized by: (i) maximizing the sphericity, (ii) maximizing the density, and (iii) minimizing microstructural features. A spheroid with these properties can be manufactured via machining a perfect sphere from a highly dense, chemically and phase pure pellet. These properties promote rotation of the sample about multiple axes in the air stream, enabling homogeneous heating. This homogeneous heating is the dominant factor in reducing thermal gradients in solid state samples. It was found that the thermal gradient in an ∼3 mm diameter solid sample could be reduced from 1000 °C to 30 °C, by having a perfectly spherical shape that could rotate on multiple axes in a high velocity gas stream (∼1500-2000 cm/min). These findings will allow accurate thermophysical and thermochemical property measurements of solids in situ at high temperatures, using the CNL system.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1063/1.5055738DOI Listing
January 2019

Combined computational and experimental investigation of high temperature thermodynamics and structure of cubic ZrO and HfO.

Sci Rep 2018 Oct 8;8(1):14962. Epub 2018 Oct 8.

Peter A. Rock Thermochemistry Laboratory and NEAT ORU, University of California Davis, Davis, CA, 95616, USA.

Structure and thermodynamics of pure cubic ZrO and HfO were studied computationally and experimentally from their tetragonal to cubic transition temperatures (2311 and 2530 °C) to their melting points (2710 and 2800 °C). Computations were performed using automated ab initio molecular dynamics techniques. High temperature synchrotron X-ray diffraction on laser heated aerodynamically levitated samples provided experimental data on volume change during tetragonal-to-cubic phase transformation (0.55 ± 0.09% for ZrO and 0.87 ± 0.08% for HfO), density and thermal expansion. Fusion enthalpies were measured using drop and catch calorimetry on laser heated levitated samples as 55 ± 7 kJ/mol for ZrO and 61 ± 10 kJ/mol for HfO, compared with 54 ± 2 and 52 ± 2 kJ/mol from computation. Volumetric thermal expansion for cubic ZrO and HfO are similar and reach (4 ± 1)·10/K from experiment and (5 ± 1)·10/K from computation. An agreement with experiment renders confidence in values obtained exclusively from computation: namely heat capacity of cubic HfO and ZrO, volume change on melting, and thermal expansion of the liquid to 3127 °C. Computed oxygen diffusion coefficients indicate that above 2400 °C pure ZrO is an excellent oxygen conductor, perhaps even better than YSZ.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-018-32848-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6175917PMC
October 2018

Probing disorder in pyrochlore oxides using in situ synchrotron diffraction from levitated solids-A thermodynamic perspective.

Sci Rep 2018 Jul 13;8(1):10658. Epub 2018 Jul 13.

Peter A. Rock Thermochemistry Laboratory and NEAT ORU, University of California Davis, One Shields Avenue, 4415 Chemistry Annex, Davis, California, 95616, USA.

Pyrochlore, an ordered derivative of the defect fluorite structure, shows complex disordering behavior as a function of composition, temperature, pressure, and radiation damage. We propose a thermodynamic model to calculate the disordering enthalpies for several REZrO (RE = Sm, Eu, Gd) pyrochlores from experimental site distribution data obtained by in situ high temperature synchrotron X-ray diffraction. Site occupancies show a gradual increase in disorder on both cation and anion sublattices with increasing temperature and even greater disorder is achieved close to the phase transition to defect fluorite. The enthalpy associated with cation disorder depends on the radius of the rare earth ion, while the enthalpy of oxygen disordering is relatively constant for different compositions. The experimental data support trends predicted by ab initio calculations, but the obtained enthalpies of disordering are less endothermic than the predicted values. Thermal expansion coefficients are in the range (8.6-10.8) × 10 K. These new experimental determinations of defect formation energies are important for understanding the stability of pyrochlore oxides and their disordering mechanisms, which are essential in the context of their potential applications in nuclear waste management and other technologies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-018-28877-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6045670PMC
July 2018

Allergen of the Month-Japanese Maple.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Dec;115(6):A17

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.10.011DOI Listing
December 2015

Short ragweeds is highly cross-reactive with other ragweeds.

Ann Allergy Asthma Immunol 2015 Dec 21;115(6):490-495.e1. Epub 2015 Oct 21.

ALK, Hørsholm, Denmark. Electronic address:

Background: The most widespread ragweed (Ambrosia) species in North America are short ragweed (Ambrosia artemisiifolia; Amb a), giant ragweed (Ambrosia trifida; Amb t), and western ragweed (Ambrosia psilostachya; Amb p). Varied geographic distributions of ragweed species raise questions regarding the need for ragweed species-specific allergen immunotherapy.

Objective: To determine allergenic cross-reactivity among ragweed species by immunologic analyses of sera from subjects allergic to ragweed from North America and Europe.

Methods: Sera were collected from 452 subjects allergic to ragweed who participated in Amb a sublingual immunotherapy tablet clinical trials. All subjects had positive skin prick test and serum IgE against Amb a. Ragweed-specific IgE (pre treatment) and IgG4 (post treatment) were measured by ImmunoCAP. IgE inhibition studies among Amb a, Amb t, and Amb p were conducted. Using pooled sera from another ragweed-allergic population, IgE inhibition studies of 7 less widespread Ambrosia species also were conducted.

Results: A strong correlation between Amb a vs Amb p and Amb t serum IgE levels was observed. In the vast majority of pretreatment sera, Amb a inhibited Amb a, Amb p, and Amb t IgE reactivity by more than 90%. Strong correlations were observed between Amb a vs Amb p and Amb t post-treatment IgG4 levels. In pooled sera, Amb a extract inhibited the binding of serum IgE to all 10 ragweed species by 98%-100%.

Conclusion: In a population of subjects allergic to Amb a, substantial allergenic cross-reactivity among Amb a, Amb p, and Amb t was demonstrated. These in vitro data suggest that an Amb a-based single-species ragweed allergen immunotherapy may be therapeutically active in patients exposed to diverse ragweed pollens.

Trial Registry: Clinicaltrials.gov, NCT00770315, NCT00783198, and NCT00330083.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.09.016DOI Listing
December 2015

Allergen of the Month--English Oak.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Nov;115(5):A13

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.09.001DOI Listing
November 2015

Allergen of the Month--Monk's Rhubarb.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Oct;115(4):A13

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.08.010DOI Listing
October 2015

Allergen of the Month--Western Red Cedar.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Sep;115(3):A11

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.07.018DOI Listing
September 2015

Miscellaneous Dental Practice Questions.

J Mich Dent Assoc 2015 May;97(5):22

View Article and Find Full Text PDF

Download full-text PDF

Source
May 2015

Allergen of the month--mucor.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Aug;115(2):A15

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.06.023DOI Listing
August 2015

Allergen of the Month--Assassin Bug.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Jul;115(1):A9

Photography: Courtesy of the Centers for Disease Control and Prevention.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.05.008DOI Listing
July 2015

Allergen of the month--annual ryegrass.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Jun;114(6):A13

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.04.018DOI Listing
June 2015

Allergen of the month--white bursage.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 May;114(5):A17

Photography: Greer Labs.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.03.015DOI Listing
May 2015

Allergen of the month-annual wormwood.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Apr;114(4):A23

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.02.014DOI Listing
April 2015

Allergen of the month--narrowleaf goosefoot.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Mar;114(3):A21

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2015.01.007DOI Listing
March 2015

Allergen of the month--sandbar willow.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Feb;114(2):A21

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2014.12.002DOI Listing
February 2015

Deviation from high-entropy configurations in the atomic distributions of a multi-principal-element alloy.

Nat Commun 2015 Jan 20;6:5964. Epub 2015 Jan 20.

Department of Materials Sciences and Engineering, The University of Tennessee, Knoxville, Tennessee 37996, USA.

The alloy-design strategy of combining multiple elements in near-equimolar ratios has shown great potential for producing exceptional engineering materials, often known as 'high-entropy alloys'. Understanding the elemental distribution, and, thus, the evolution of the configurational entropy during solidification, is undertaken in the present study using the Al₁.₃CoCrCuFeNi model alloy. Here we show that, even when the material undergoes elemental segregation, precipitation, chemical ordering and spinodal decomposition, a significant amount of disorder remains, due to the distributions of multiple elements in the major phases. The results suggest that the high-entropy alloy-design strategy may be applied to a wide range of complex materials, and should not be limited to the goal of creating single-phase solid solutions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/ncomms6964DOI Listing
January 2015

Allergen of the month--Stemphylium.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2015 Jan;114(1):A11

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2014.11.008DOI Listing
January 2015

Allergen of the month--black wattle.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2014 Dec;113(6):A13

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2014.10.017DOI Listing
December 2014

Allergen of the month--Chinese elm.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2014 Nov 5;113(5):A15. Epub 2014 Nov 5.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2014.09.004DOI Listing
November 2014

Allergen of the month--Utah juniper.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2014 Oct;113(4):A21

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2014.08.008DOI Listing
October 2014

Allergen of the month--field maple.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2014 Sep;113(3):A15

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2014.07.024DOI Listing
September 2014

Allergen of the month--Little-leaf linden.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2014 Aug;113(2):A15

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2014.06.015DOI Listing
August 2014

Allergen of the month--meadow fescue.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2014 Jul;113(1):A11

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2014.05.018DOI Listing
July 2014

Allergen of the month--rabbit.

Authors:
Richard W Weber

Ann Allergy Asthma Immunol 2014 Jun;112(6):A13

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2014.04.015DOI Listing
June 2014

Allergen of the month--Fusarium.

Ann Allergy Asthma Immunol 2014 May;112(5):A11

Biological Science, University of Tulsa.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.anai.2014.03.015DOI Listing
May 2014