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Full-Text Articles in Physical Sciences and Mathematics

Temporal Variation In Optical Properties Of Chromophoric Dissolved Organic Matter (Cdom) In Southern California Coastal Waters With Nearshore Kelp And Seagrass, Catherine D. Clark, Warren J. De Bruyn, Paige Aiona Oct 2015

Temporal Variation In Optical Properties Of Chromophoric Dissolved Organic Matter (Cdom) In Southern California Coastal Waters With Nearshore Kelp And Seagrass, Catherine D. Clark, Warren J. De Bruyn, Paige Aiona

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Optical properties of chromophoric dissolved organic matter (CDOM) were measured in surf zone waters in diurnal field studies at a Southern California beach with nearshore kelp and seagrass beds and intertidal plant wrack. Absorption coefficients (aCDOM(300 nm)) ranged from 0.35 m21 to 3.7 m21 with short-term variability<1 h, increases at ebb and flood tides and higher values (6 m21) during an offshore storm event. Spectral slopes (S) ranged from 0.0028 nm21 to 0.017 nm21, with higher values after the storm; S was generally inversely correlated with aCDOM(300 nm). 3-D excitation–emission matrix spectra (EEMs) for samples with lower S values had humic-type peaks associated with terrestrial material (A, C), marine microbial material (M) and protein peaks, characteristic of freshly produced organic material. Samples with high S values had no or reduced protein peaks, consistent with aged material. Fluorescent indexes (f450/f500 >2.5, BIX>1.1) were consistent with microbial aquatic sources. Leachates of senescent kelp and seagrass had protein and humic-type EEM peaks. After solar simulator irradiation (4 h), protein peaks rapidly photochemically degraded, humic-type peak C increased in intensity and peak M disappeared. Optical characteristics of kelp leachates were most similar to field samples, …


Rapid Label-Free Detection Of E. Coli Using Antimicrobial Peptide Assisted Impedance Spectroscopy, Keren Jieng, Hashem Etayash, Sarfuddin Azmi, Selvaraj Naicker, Mahtab Hassanpourfard, Parmiss Mojir Shaibani, Garima Thakur, Kamaljit Kaur, Thomas Thundat Aug 2015

Rapid Label-Free Detection Of E. Coli Using Antimicrobial Peptide Assisted Impedance Spectroscopy, Keren Jieng, Hashem Etayash, Sarfuddin Azmi, Selvaraj Naicker, Mahtab Hassanpourfard, Parmiss Mojir Shaibani, Garima Thakur, Kamaljit Kaur, Thomas Thundat

Pharmacy Faculty Articles and Research

There is an increasing demand for rapid detection of waterborne pathogens to monitor drinking water safety. We demonstrate a compact, label-free sensor array for rapid detection of Escherichia coli (E. coli) in contaminated water samples using antimicrobial peptide assisted impedimetric sensor platform. Interdigitated electrode arrays immobilized with the antimicrobial peptide Colicin V (ColV) were used to screen the affinity towards different bacterial strains by monitoring impedance variations in real-time. This ColV assisted impedance biosensor exhibited high selectivity towards Gram-negative strains particularly towards E. coli strains. This selective detection of E. coli from other strains was observed at 10 …


On The Relationship Between The North Atlantic Oscillation And Early Warm Season Temperatures In The Southwestern United States, Boksoon Myoung, Seung Hee Kim, Jinwon Kim, Menas Kafatos Jul 2015

On The Relationship Between The North Atlantic Oscillation And Early Warm Season Temperatures In The Southwestern United States, Boksoon Myoung, Seung Hee Kim, Jinwon Kim, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

It is reported herein that the North Atlantic Oscillation (NAO), which has been known to directly affect winter weather conditions in western Europe and the eastern United States, is also linked to surface air temperature over the broad southwestern U.S. (SWUS) region, encompassing California, Nevada, Arizona, New Mexico, Utah, and Colorado, in the early warm season. The authors have performed monthly time-scale correlations and composite analyses using three different multidecadal temperature datasets. Results from these analyses reveal that NAO-related upstream circulation positively affects not only the means, but also the extremes, of the daily maximum and minimum temperatures in the …


Dimethylsulfide Gas Transfer Coefficients From Algal Blooms In The Southern Ocean, T. G. Bell, Warren J. De Bruyn, Christa A. Marandino, S. D. Miller, C. S. Law, Eric S. Saltzman Jan 2015

Dimethylsulfide Gas Transfer Coefficients From Algal Blooms In The Southern Ocean, T. G. Bell, Warren J. De Bruyn, Christa A. Marandino, S. D. Miller, C. S. Law, Eric S. Saltzman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Air-sea dimethylsulfide (DMS) fluxes and bulk air-sea gradients were measured over the Southern Ocean in February-March 2012 during the Surface Ocean Aerosol Production (SOAP) study. The cruise encountered three distinct phytoplankton bloom regions, consisting of two blooms with moderate DMS levels, and a high biomass, dinoflagellate-dominated bloom with high seawater DMS levels (> 15 nM). Gas transfer coefficients were considerably scattered at wind speeds above 5 m s(-1). Bin averaging the data resulted in a linear relationship between wind speed and mean gas transfer velocity consistent with that previously observed. However, the wind-speed-binned gas transfer data distribution at all wind …


Aerosol Optical Properties Over Mount Song, A Rural Site In Central China, Lunche Wang, Wei Gong, Ramesh P. Singh, Xiangao Xia, Huizheng Che, Ming Zhang, Hong Lin Jan 2015

Aerosol Optical Properties Over Mount Song, A Rural Site In Central China, Lunche Wang, Wei Gong, Ramesh P. Singh, Xiangao Xia, Huizheng Che, Ming Zhang, Hong Lin

Mathematics, Physics, and Computer Science Faculty Articles and Research

Seasonal variations of aerosol optical depth (AOD), Ångström exponent (α), single scattering albedo (SSA), water vapor content (WVC), aerosol size distribution and refractive index at Mount Song, a rural site in Central China are analyzed using ground-based sunphotometer data for the period April 2012 to May 2014 for the first time. The results show that the area is highly polluted even the major anthropogenic emission sources are far away. Seasonal mean AOD is high (0.72 ± 0.52) during summer (June–August) season and low (0.51 ± 0.38) during autumn (September–November) season. The monthly mean α is very low (0.81 ± 0.30) …


Study Of Aerosols’ Characteristics And Dynamics Over The Kingdom Of Saudi Arabia Using A Multisensor Approach Combined With Ground Observations, Ashraf Farahat, Hesham El-Askary, Abdulaziz Al-Shaibani Jan 2015

Study Of Aerosols’ Characteristics And Dynamics Over The Kingdom Of Saudi Arabia Using A Multisensor Approach Combined With Ground Observations, Ashraf Farahat, Hesham El-Askary, Abdulaziz Al-Shaibani

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

This study covers various aspects of the aerosol distribution and characteristics, namely, optical depth climatology, absorption characteristics, and their microphysical properties over four regions in Saudi Arabia using satellite and ground observations including MODIS/Terra and Aqua, OMI, MISR/Terra, AERONET, and CALIPSO for the period April 2003–January 2013. The study includes cities in the North Western, Western, Eastern provinces of Saudi Arabia and in the Rub al Khali desert or Empty Quarter. Satellite and ground observations showed that the dust season extends from April to August with prominent peaks yet with high anthropogenic contribution late summer and early fall. Analysis shows …


Studying Air Pollutants Origin And Associated Meteorological Parameters Over Seoul From 2000 To 2009, Sunmin Park, Hesham El-Askary, Ismail Sabbah, Hanbin Kwak, Anup K. Prasad, Woo-Kyun Lee, Menas Kafatos Jan 2015

Studying Air Pollutants Origin And Associated Meteorological Parameters Over Seoul From 2000 To 2009, Sunmin Park, Hesham El-Askary, Ismail Sabbah, Hanbin Kwak, Anup K. Prasad, Woo-Kyun Lee, Menas Kafatos

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We investigate the temporal characteristics of major air pollutants collected from 44 air quality stations over the city of Seoul, Korea, namely, nitrogen dioxide, carbon monoxide, particular matter at 10 microns, and sulfur dioxide (SO2) between 2000 and 2009. The corresponding satellite datasets, namely, aerosol optical depth (AODsat), Ångström exponent, and fine mode fraction, collected from moderate resolution imaging spectroradiometer (MODIS) as well as the Aeronet ground aerosol optical depth (AODaeronet), have been analyzed. Pollutants’ seasonal effect has been inferred from the precipitation and temperature. The four pollutants under study show varying temporal characteristics with different …


Spatial Analyses On Seismo-Ionospheric Precursors Observed By Gim Tec And Demeter During The 2008 M8.0wenchuan Earthquake, Jann-Yenq Liu, Yuh-Ing Chen, Cheng-Chi Huang, Michel Parrot, Sergey Pulintets, Dimitar Ouzounov Jan 2015

Spatial Analyses On Seismo-Ionospheric Precursors Observed By Gim Tec And Demeter During The 2008 M8.0wenchuan Earthquake, Jann-Yenq Liu, Yuh-Ing Chen, Cheng-Chi Huang, Michel Parrot, Sergey Pulintets, Dimitar Ouzounov

Mathematics, Physics, and Computer Science Faculty Articles and Research

An abstract of the "Spatial analyses on seismo-ionospheric precursors observed by GIM TEC and DEMETER during the 2008 M8.0Wenchuan earthquake" paper presented at EGU General Assembly in 2015.


Remote Sensing And Modeling Of Atmospheric Dust And Studying Its Impact On Environment, Weather, And Climate, Hesham El-Askary, Seon K. Park, Slobodan Nickovic, Mian Chin Jan 2015

Remote Sensing And Modeling Of Atmospheric Dust And Studying Its Impact On Environment, Weather, And Climate, Hesham El-Askary, Seon K. Park, Slobodan Nickovic, Mian Chin

Mathematics, Physics, and Computer Science Faculty Articles and Research

An overview of the 2015 volume of Advances in Meteorology, which was co-edited by Chapman faculty member Dr. Hesham El-Askary.


On The Detection And Monitoring Of The Transport Of An Asian Dust Storm Using Multi-Sensor Satellite Remote Sensing, Hesham El-Askary, S. K. Park, M. H. Ahn, A. Prasad, Menas Kafatos Jan 2015

On The Detection And Monitoring Of The Transport Of An Asian Dust Storm Using Multi-Sensor Satellite Remote Sensing, Hesham El-Askary, S. K. Park, M. H. Ahn, A. Prasad, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

Dynamical and physical features of a long range transported dust event originating in China affecting Korea early March 2008 are examined using an integrative multi-sensor and multi-algorithm approach. Aerosol loadings and their size mode were analyzed over both ocean and land surfaces using the Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth (AOD), employing standard dark target (DT) and deep blue (DB) algorithms, and the Ångström exponent (AE). Anthropogenic absorbing aerosols and smoke were found to be significant over the Indochina Peninsula, the Philippines and southern China, while a mixture of dust and pollution were predominant over central to northern …