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Minimum environmental potassium for survival of Pacific white shrimp Litopenaeus vannamei (Boone) in freshwater
Title
Minimum environmental potassium for survival of Pacific white shrimp Litopenaeus vannamei (Boone) in freshwater.
Creator
McGraw, William J., Scarpa, John, Harbor Branch Oceanographic Institute
Date Issued
2003
PURL
http://purl.flvc.org/FCLA/DT/3174055
Subject Headings
Shrimps, Freshwater, Osmoregulation, Potassium, Ions
Format
Document (PDF)
Hematocrit, osmolality and ion concentration in fishes: consideration of circadian patterns in the experimental design
Title
Hematocrit, osmolality and ion concentration in fishes: consideration of circadian patterns in the experimental design.
Creator
Peterson, Mark S., Gilmore, R. G., Harbor Branch Oceanographic Institute
Date Issued
1988
PURL
http://purl.flvc.org/FCLA/DT/3353815
Subject Headings
Fishes, Hematocrit, Osmoregulation, Ions, Circadian rhythms, Chlorides
Format
Document (PDF)
Synthesis characterization and ion exchange properties of aluminum phosphonates
Title
Synthesis characterization and ion exchange properties of aluminum phosphonates.
Creator
McCormack, Rupert Garth, Florida Atlantic University, Haky, Jerome E.
Abstract/Description
Three aluminum organophosphonate compounds; aluminum phenylphosphonate, aluminum octylphosphonate, and aluminum octadecylphosphonate, have been synthesized by refluxing aluminum nitrate with an excess of the appropriate organophosphonic acid in aqueous, methanol, or butanol solvents respectively. Each of these compounds was found to have pillared layered structures and ligand to metal ratios of 2:1. Additionally, these compounds were shown to exhibit cation exchange properties. In contrast to...
Show moreThree aluminum organophosphonate compounds; aluminum phenylphosphonate, aluminum octylphosphonate, and aluminum octadecylphosphonate, have been synthesized by refluxing aluminum nitrate with an excess of the appropriate organophosphonic acid in aqueous, methanol, or butanol solvents respectively. Each of these compounds was found to have pillared layered structures and ligand to metal ratios of 2:1. Additionally, these compounds were shown to exhibit cation exchange properties. In contrast to that observed for conventional cation-exchange resins, the exchange capacities of these compounds are larger for small cations, such as Li+ and Na+, than for larger ions such as Na+ and K+. The results indicate a size selectivity which is directly related to the accessibility of these ions to the exchangeable sites of these compounds.
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Date Issued
2001
PURL
http://purl.flvc.org/fcla/dt/12748
Subject Headings
Inorganic ion exchange materials, Phosphonates, Aluminum compounds
Format
Document (PDF)
Fractal methods to analyze ion channel kinetics
Title
Fractal methods to analyze ion channel kinetics.
Creator
Liebovitch, Larry S., Scheurle, Daniela, Rusek, Marian, Zochowskis, Michal
Date Issued
2001-08
PURL
http://purl.flvc.org/FAU/165246
Subject Headings
Fractals, Ion Channels-Mathematical models, Ion flow dynamics, Biomathematics, Chaotic behavior in systems
Format
Document (PDF)
Demonstrations and laboratory exercises in aquaculture. II. Activated carbon and ion-exchange in chemical filtration
Title
Demonstrations and laboratory exercises in aquaculture. II. Activated carbon and ion-exchange in chemical filtration.
Creator
Landau, Matthew P., Scarpa, John
Date Issued
2001
PURL
http://purl.flvc.org/FCLA/DT/3352967
Subject Headings
Aquaculture, Carbon, Activated, Ion exchange, Filters and filtration, Demonstrations
Format
Document (PDF)
Effects of seawater exchange, pH and carbon supply on the growth of Gracilaria tikvahiae (Rhodophyceae) in large-scale cultures
Title
Effects of seawater exchange, pH and carbon supply on the growth of Gracilaria tikvahiae (Rhodophyceae) in large-scale cultures.
Creator
DeBusk, T. A., Ryther, John H., Harbor Branch Oceanographic Institute
Date Issued
1984
PURL
http://purl.flvc.org/fau/fd/FA00007019
Subject Headings
Gracilaria, Algae culture, Seawater, Hydrogen-ion concentration, Carbon
Format
Document (PDF)
Mortality of freshwater-acclimated Litopenaeus vannamei associated with acclimation rate, habituation period, and ionic challenge
Title
Mortality of freshwater-acclimated Litopenaeus vannamei associated with acclimation rate, habituation period, and ionic challenge.
Creator
McGraw, William J., Scarpa, John
Date Issued
2004
PURL
http://purl.flvc.org/FCLA/DT/2848317
Subject Headings
Climatic changes, Habituation (Neuropsychology), Ions --Congresses, Shrimp culture, Aquaculture
Format
Document (PDF)
Photoluminescence characterization of zinc(1-x) manganese(x) sulfur under different excitation sources
Title
Photoluminescence characterization of zinc(1-x) manganese(x) sulfur under different excitation sources.
Creator
Ye, Yubin, Florida Atlantic University, Medina, Fernando D.
Abstract/Description
A study of the temperature dependence of the photoluminescence spectra from Zn1-xMnxS (x = 0.01, 0.03, 0.05, 0.10, 0.20, 0.25, 0.30, 0.35 and 0.50) with different excitation energies (514.5, 488.0, 457.9, 405.5 and 365.9 nm) is given. A new band is reported in addition to the four usual emission bands. The unusual shift of the 2.1 eV (YEL) band energy is first observed in our experiments. Models for YEL, ORG (2.0 eV) and RED (1.7 eV) emission bands have been proposed. The quenching with...
Show moreA study of the temperature dependence of the photoluminescence spectra from Zn1-xMnxS (x = 0.01, 0.03, 0.05, 0.10, 0.20, 0.25, 0.30, 0.35 and 0.50) with different excitation energies (514.5, 488.0, 457.9, 405.5 and 365.9 nm) is given. A new band is reported in addition to the four usual emission bands. The unusual shift of the 2.1 eV (YEL) band energy is first observed in our experiments. Models for YEL, ORG (2.0 eV) and RED (1.7 eV) emission bands have been proposed. The quenching with concentration and temperature and the influence of excitation energy on the photoluminescence are discussed. The spin-spin exchange interaction between the nearest neighbor Mn^+2 ions (d-d electrons), and the exchange interaction between 3d electrons of Mn^+2 ions and the conduction or valence band electrons (d-s or d-p electrons) are introduced to interpret the shift of the bands. The strong electron-phonon interaction is also analyzed, and an effective phonon energy and a Huang-Rhys factor are obtained.
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Date Issued
1993
PURL
http://purl.flvc.org/fcla/dt/14988
Subject Headings
Semiconductors, Magnetic ions, X-ray spectroscopy, Zinc sulfide crystals
Format
Document (PDF)
The Dynamic pH Landscape At The Drosophila NMJ Synaptic Cleft And Its Implication In Neurotransmission
Title
The Dynamic pH Landscape At The Drosophila NMJ Synaptic Cleft And Its Implication In Neurotransmission.
Creator
Hernandez, Roberto X., Macleod, Gregory T., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description
The intricate processes governing cellular pH and its impact on protein and cellular function have been extensively explored. However, our understanding of the pH fluctuations that occur during routine cellular activities and their potential to modulate cell function remains, particularly within the highly dynamic pH landscape of a synapse. Investigating the scale, directionality, and temporal characteristics of these activity-dependent pH fluctuations at synapses is of paramount interest, as...
Show moreThe intricate processes governing cellular pH and its impact on protein and cellular function have been extensively explored. However, our understanding of the pH fluctuations that occur during routine cellular activities and their potential to modulate cell function remains, particularly within the highly dynamic pH landscape of a synapse. Investigating the scale, directionality, and temporal characteristics of these activity-dependent pH fluctuations at synapses is of paramount interest, as it carries profound implications for neurotransmitter release and signal transduction. Employing both empirical and computational modeling methods, our research explores the dynamic pH environment within the synaptic cleft of Drosophila glutamatergic motor neuron Ib terminals during synaptic activity and reveals its significance in modulating neurotransmission. Contrary to popular belief, we discovered that these terminals undergo activity-dependent extracellular alkalinization in response to both single action potentials and burst stimulation. This surprising phenomenon was also observed at the mouse calyx of Held. We found activity-dependent alkalinization to be predominantly driven by Ca2+ movement across the postsynaptic membrane, and by targeting pH indicators to subcellular domains, we identified alkalinization to primarily occur within the cleft.
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Date Issued
2023
PURL
http://purl.flvc.org/fau/fd/FA00014346
Subject Headings
Neurotransmission, Drosophila, Hydrogen-Ion Concentration, Motor Neurons, Optogenetics
Format
Document (PDF)
Legends that sleep kick Bogotá at night
Title
Legends that sleep kick Bogotá at night.
Creator
Burgos, Diana, Bucak, Ayse Papatya, Florida Atlantic University, Dorothy F. Schmidt College of Arts and Letters, Department of English
Abstract/Description
Legends That Sleep Kick Bogotá at Night is a short story collection that parodies the gender, moral, and social constructs of Colombian mythology and folklore. Set in contemporary times, the stories depict slews of grotesque transformations and rituals happening during plane flights, sibling tomfoolery, neck kisses, social network log-ins, trips to the family graveyard, conversations with escorts, and waves of town gossip. The folktale monsters aim to enlist the reader as their accomplice in...
Show moreLegends That Sleep Kick Bogotá at Night is a short story collection that parodies the gender, moral, and social constructs of Colombian mythology and folklore. Set in contemporary times, the stories depict slews of grotesque transformations and rituals happening during plane flights, sibling tomfoolery, neck kisses, social network log-ins, trips to the family graveyard, conversations with escorts, and waves of town gossip. The folktale monsters aim to enlist the reader as their accomplice in their quest to fight against the forces that seek to permanently subdue and marginalize them.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00004270, http://purl.flvc.org/fau/fd/FA00004270
Subject Headings
Physics., Nuclear physics., Heavy ions., Hadrons., Particle acceleration., Condensed matter., Engineering., Materials science., Physics., Nuclear Physics, Heavy Ions, Hadrons.
Format
Document (PDF)
Introduction to fractals
Title
Introduction to fractals.
Creator
Liebovitch, Larry S., Shehadeh, Lina A.
PURL
http://purl.flvc.org/fau/165810
Subject Headings
Fractals, Chaotic behavior in systems, Nonlinear systems--Mathematical models, Ion channels, Psychology
Format
Document (PDF)
pH Dynamics within the Drosophila Synaptic Cleft During Activity
Title
pH Dynamics within the Drosophila Synaptic Cleft During Activity.
Creator
Feghhi, Touhid, Lau, Andy W.C., Macleod, Gregory T., Florida Atlantic University, Department of Physics, Charles E. Schmidt College of Science
Abstract/Description
Acute pH sensitivity of many neural mechanisms highlights the vulnerability of neurotransmission to the pH of the extracellular milieu. The dogma is that the synaptic cleft will acidify upon neurotransmission because the synaptic vesicles corelease neurotransmitters and protons to the cleft, and the direct data from sensory ribbon-type synapses support the acidification of the cleft. However, ribbon synapses have a much higher release probability than conventional synapses, and it’s not...
Show moreAcute pH sensitivity of many neural mechanisms highlights the vulnerability of neurotransmission to the pH of the extracellular milieu. The dogma is that the synaptic cleft will acidify upon neurotransmission because the synaptic vesicles corelease neurotransmitters and protons to the cleft, and the direct data from sensory ribbon-type synapses support the acidification of the cleft. However, ribbon synapses have a much higher release probability than conventional synapses, and it’s not established whether conventional synapses acidify as well. To test the acidification of the cleft in the conventional synapse, we used genetically encoded fluorescent pH reporters targeted to the synaptic cleft of Drosophila larvae. We observed alkalinization rather than acidification during activity, and this alkalinization was dependent on the exchange of protons for calcium at the postsynaptic membrane. A reaction-diffusion computational model of the pH dynamics at the Drosophila larval neuromuscular junction was developed to leverage the experimental data. The model incorporates the release of glutamate, ATP, and protons from synaptic vesicles into the cleft, PMCA activity, bicarbonate, and phosphate buffering systems. By means of numerical simulations, we reveal a highly dynamic pH landscape within the synaptic cleft, harboring deep but exceedingly rapid acid transients that give way to a prolonged period of alkalinization.
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Date Issued
2023
PURL
http://purl.flvc.org/fau/fd/FA00014221
Subject Headings
Synapses, pH (Chemistry), Hydrogen-ion concentration., Synaptic Transmission, Drosophila
Format
Document (PDF)
Hurst analysis applied to the study of single calcium-activated potassium channel kinetics
Title
Hurst analysis applied to the study of single calcium-activated potassium channel kinetics.
Creator
Liebovitch, Larry S., Figueiroa, Josed N., Nogueira, Romildo A., Varanda, Wamberto A.
Date Issued
2000-10-07
PURL
http://purl.flvc.org/FAU/165249
Subject Headings
Ion channels-Mathematical models, Memory, Chemical kinetics, Calcium channels, Fractals, Markov processes, Leydig cells, Molecular biology--Statistical methods
Format
Document (PDF)
Fractal ion-channel behavior generates fractal firing patterns in neuronal models
Title
Fractal ion-channel behavior generates fractal firing patterns in neuronal models.
Creator
Liebovitch, Larry S., Lowen, Steven B., White, John A.
Date Issued
1999-05
PURL
http://purl.flvc.org/fau/165477
Subject Headings
Biophysics--Research, Fractals, Neural networks (Neurobiology)--Mathematical models, Neurons--Mathematical models, Markov processes--Mathematical models, Ion channels--Mathematical models
Format
Document (PDF)
A dosimetric study of a heterogeneous phantom for lung stereotactic body radiation therapy comparing Monte Carlo and pencil beam calculations to dose distributions measured with a 2-d diode array
Title
A dosimetric study of a heterogeneous phantom for lung stereotactic body radiation therapy comparing Monte Carlo and pencil beam calculations to dose distributions measured with a 2-d diode array.
Creator
Curley, Casey Michael, Ouhib, Zoubir, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description
Monte Carlo (MC) and Pencil Beam (PB) calculations are compared to their measured planar dose distributions using a 2-D diode array for lung Stereotactic Body Radiation Therapy (SBRT). The planar dose distributions were studied for two different phantom types: an in-house heterogeneous phantom and a homogeneous phantom. The motivation is to mimic the human anatomy during a lung SBRT treatment and incorporate heterogeneities into the pre-treatment Quality Assurance process, where measured and...
Show moreMonte Carlo (MC) and Pencil Beam (PB) calculations are compared to their measured planar dose distributions using a 2-D diode array for lung Stereotactic Body Radiation Therapy (SBRT). The planar dose distributions were studied for two different phantom types: an in-house heterogeneous phantom and a homogeneous phantom. The motivation is to mimic the human anatomy during a lung SBRT treatment and incorporate heterogeneities into the pre-treatment Quality Assurance process, where measured and calculated planar dose distributions are compared before the radiation treatment. Individual and combined field dosimetry has been performed for both fixed gantry angle (anterior to posterior) and planned gantry angle delivery. A gamma analysis has been performed for all beam arrangements. The measurements were obtained using the 2-D diode array MapCHECK 2™.
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Date Issued
2015
PURL
http://purl.flvc.org/fau/fd/FA00004360
Subject Headings
Cancer -- Radiotherapy, Drug development -- Computer simulation, Image guided radiation therapy, Ion bombardment, Lung cancer -- Treatment, Medical physics, Monte Carlo method, Proton beams
Format
Document (PDF)
Phantom Study Incorporating A Diode Array Into The Treatment Planning System For Patient-Specific Quality Assurance
Title
Phantom Study Incorporating A Diode Array Into The Treatment Planning System For Patient-Specific Quality Assurance.
Creator
Curley, Casey Michael, Leventouri, Theodora, Ouhib, Zoubir, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description
The purpose of this research is to accurately match the calculation environment, i.e. the treatment planning system (TPS) with the measurement environment (using a 2-D diode array) for lung Stereotactic Body Radiation Therapy (SBRT) patient-specific quality assurance (QA). Furthermore, a new phantom was studied in which the 2-D array and heterogeneities were incorporated into the patient-specific QA process for lung SBRT. Dual source dual energy computerized tomography (DSCT) and single...
Show moreThe purpose of this research is to accurately match the calculation environment, i.e. the treatment planning system (TPS) with the measurement environment (using a 2-D diode array) for lung Stereotactic Body Radiation Therapy (SBRT) patient-specific quality assurance (QA). Furthermore, a new phantom was studied in which the 2-D array and heterogeneities were incorporated into the patient-specific QA process for lung SBRT. Dual source dual energy computerized tomography (DSCT) and single energy computerized tomography (SECT) were used to model phantoms incorporating a 2-D diode array into the TPS. A water-equivalent and a heterogeneous phantom (simulating the thoracic region of a patient) were studied. Monte Carlo and pencil beam dose distributions were compared to the measured distributions. Composite and individual fields were analyzed for normally incident and planned gantry angle deliveries. The distributions were compared using γ-analysis for criteria 3% 3mm, 2% 2mm, and 1% 1mm. The Monte Carlo calculations for the DSCT modeled phantoms (incorporating the array) showed an increase in the passing percentage magnitude for 46.4 % of the fields at 3% 3mm, 85.7% at 2% 2mm, and 92.9% at 1% 1mm. The Monte Carlo calculations gave no agreement for the same γ-analysis criteria using the SECT. Pencil beam calculations resulted in lower passing percentages when the diode array was incorporated in the TPS. The DSCT modeled phantoms (incorporating the array) exhibited decrease in the passing percentage magnitude for 85.7% of the fields at 3% 3mm, 82.1% at 2% 2mm, and 71.4% at 1% 1mm. In SECT modeled phantoms (incorporating the array), a decrease in passing percentage magnitude were found for 92.9% of the fields at 3% 3mm, 89.3% at 2% 2mm, and 82.1% at 1% 1mm. In conclusion, this study demonstrates that including the diode array in the TPS results in increased passing percentages when using a DSCT system with a Monte Carlo algorithm for patient-specific lung SBRT QA. Furthermore, as recommended by task groups (e.g. TG 65, TG 101, TG 244) of the American Association of Physicists in Medicine (AAPM), pencil beam algorithms should be avoided in the presence of heterogeneous materials, including a diode array.
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Date Issued
2016
PURL
http://purl.flvc.org/fau/fd/FA00004744, http://purl.flvc.org/fau/fd/FA00004744
Subject Headings
Cancer--Radiotherapy., Lungs--Cancer--Treatment., Monte Carlo method., Proton beams., Image-guided radiation therapy., Ion bombardment., Medical physics.
Format
Document (PDF)