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1.
J Morphol ; 283(1): 35-50, 2022 01.
Article in English | MEDLINE | ID: mdl-34726289

ABSTRACT

Studies on size changes of Ophiuroidea are limited, despite their importance and implications in taxonomy, phylogenetics, ecology, and distribution. These studies have traditionally been based on descriptive size series seldom integrating quantitative analyses to assess the morphological variability of species, despite their potential use to study size changes in brittle stars. To confirm the latter, size changes of Ophiocomella alexandri were studied here using this approach. The studied size series of O. alexandri included specimens from 1.64 to 23.64 mm disc diameter (DD). Quantitative and qualitative external morphological characters were examined on each specimen, and quantitative analyses (cluster, one-way permutational analysis of variance, and discriminant analysis) were employed to identify size groups within the species. The allometric relationship disc diameter-total arm length (DD-AL) was estimated for each size group and the combined size groups. Two size groups were identified: Group 1, subdivided into Subgroup 1.1 and Subgroup 1.2, and Group 2. Each size group presented particular characters which were described, discussed, and compared with relevant literature. The relationship DD-AL was positively allometric for Group 1 and combined size groups, and isometric for Group 2. The results highlight the potential of quantitative analyses to address size-related morphological changes in ophiuroids, and the importance of conducting this type of study to correctly identify species regardless of their size. This is the first study to describe size-related morphological changes of a brittle star from the Eastern Pacific, and the first one focused on a member of Ophiocomidae globally.


Subject(s)
Echinodermata , Ecology , Animals , Phylogeny
2.
Zootaxa ; 4455(3): 454-470, 2018 Aug 03.
Article in English | MEDLINE | ID: mdl-30314193

ABSTRACT

Hydroids of the Pacific coast of Mexico have been little studied. For the coast of Oaxaca, only five papers provide information on species of the region, with some records included in those publications being questionable. Seven species, Pennaria disticha, Clytia linearis, Clytia cf. gracilis, Obelia dichotoma, Ventromma halecioides, Dynamena crisioides and Tridentata turbinata, were discovered during the study and are reported herein. Of these species, Pennaria disticha and Tridentata turbinata are new records for the Mexican Pacific coast, and Clytia linearis and Ventromma halecioides are new records for Oaxaca. Geographic ranges of other hydroids, recorded in earlier studies, are expanded.


Subject(s)
Cnidaria , Hydrozoa , Animals , Mexico
3.
ACS Appl Mater Interfaces ; 7(4): 2202-13, 2015 Feb 04.
Article in English | MEDLINE | ID: mdl-25562778

ABSTRACT

A composite material consisting of TiO2 nanotubes (NT) with WO3 electrodeposited on its surface has been fabricated, detached from its Ti substrate, and attached to a fluorine-doped tin oxide (FTO) film on glass for application to electrochromic (EC) reactions. Several adhesion layers were tested, finding that a paste of TiO2 made from commercially available TiO2 nanoparticles creates an interface for the TiO2 NT film to attach to the FTO glass, which is conductive and does not cause solution-phase ions in an electrolyte to bind irreversibly with the material. The effect of NT length and WO3 concentration on the EC performance were studied. The composite WO3/TiO2 nanostructures showed higher ion storage capacity, better stability, enhanced EC contrast, and longer memory time compared with the pure WO3 and TiO2 materials.

4.
ACS Appl Mater Interfaces ; 5(23): 12400-10, 2013 Dec 11.
Article in English | MEDLINE | ID: mdl-24195676

ABSTRACT

Composite WO3/TiO2 nanostructures with optimal properties that enhance solar photoconversion reactions were developed, characterized, and tested. The TiO2 nanotubes were prepared by anodization of Ti foil and used as substrates for WO3 electrodeposition. The WO3 electrodeposition parameters were controlled to develop unique WO3 nanostructures with enhanced photoelectrochemical properties. Scanning electron microscopy (SEM) images showed that the nanomaterials with optimal photocurrent density have the same ordered structure as TiO2 nanotubes, with an external tubular nanostructured WO3 layer. Diffuse reflectance spectra showed an increase in the visible absorption relative to bare TiO2 nanotubes and in the UV absorption relative to bare WO3 films. Incident simulated solar photon-to-current efficiency (IPCE) increased from 30% (for bare WO3) to 50% (for tubular WO3/TiO2 composites). With the addition of diverse organic pollutants, the photocurrent densities exhibited more than a 5-fold increase. Chemical oxygen demand measurements showed the simultaneous photodegradation of organic pollutants. The results of this work showed that the unique structure and composition of these composite WO3/TiO2 materials enhance the IPCE efficiencies, optical properties, and photodegradation performance compared with the parent materials.

5.
Solid State Nucl Magn Reson ; 35(2): 74-81, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19307109

ABSTRACT

Carbon-doped TiO(2) have received attention recently because of their potential for environmental photocatalysis and solar hydrogen conversion applications. Three different carbon-doped TiO(2) nanoparticle materials were synthesized via sol-gel and hydrothermal procedures, and analyzed by (13)C solid-state nuclear magnetic resonance (SSNMR) and other methods to characterize the environment of the doping species. UV/vis spectra and powder X-ray diffraction (XRD) patterns showed that the synthesized materials absorbed visible light and their crystal structures corresponded to anatase. (13)C SSNMR analyses of TiO(2-)(x)C(x) displayed signals corresponding to carbonate-type or sp(2)-type carbon species. Variable contact CP-MAS and dipolar dephasing analyses gave evidence for the presence and proximity of H atoms near these carbonate species. Electron paramagnetic resonance (EPR) spectroscopy showed that the thermally oxidized TiO(2-)(x)C(x) displayed a complex mixture of point defects, electron and hole trapping centers, all attributable to the incorporation of carbon, while the XPS data ruled out the presence of carbide species.


Subject(s)
Carbon/analysis , Carbon/chemistry , Electron Spin Resonance Spectroscopy/methods , Magnetic Resonance Spectroscopy/methods , Titanium/analysis , Titanium/chemistry , Catalysis , Molecular Conformation , Nanoparticles/chemistry , Photochemical Processes
7.
Int J Neurosci ; 115(3): 423-9, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15825247

ABSTRACT

Pregnant women (N = 131) were recruited at a prenatal ultrasound clinic between 20 and 28 weeks (M = 24 weeks) gestation. The women were given the CES-D for depression and the State-Trait Anxiety Inventory and were asked to provide a urine sample to be assayed for cortisol, norepinephrine, epinephrine, dopamine, and serotonin. Ultrasound sessions were conducted and coded for fetal activity and estimated fetal weight. Regression analyses were then conducted with fetal activity and fetal weight as outcome variables. Gestational age entered both analyses as the first variable followed by: (1) prenatal cortisol as a significant predictor of fetal activity; and (2) prenatal cortisol as a significant predictor of estimated fetal weight.


Subject(s)
Fetal Development/physiology , Hydrocortisone/urine , Pregnancy Trimester, Second/urine , Adult , Anxiety/urine , Depression/urine , Dopamine/urine , Epinephrine/urine , Female , Fetal Weight , Humans , Maternal-Fetal Exchange , Norepinephrine/urine , Predictive Value of Tests , Pregnancy , Serotonin/urine , Ultrasonography, Prenatal
8.
Int J Neurosci ; 115(2): 207-22, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15764002

ABSTRACT

Alertness, mood, and math computations were assessed in 11 healthy adults who sniffed a cosmetic cleansing gel with lavender floral blend aroma, developed to be relaxing using Mood Mapping. EEG patterns and heart rate were also recorded before, during, and after the aroma session. The lavender fragrance blend had a significant transient effect of improving mood, making people feel more relaxed, and performing the math computation faster. The self-report and physiological data are consistent with relaxation profiles during other sensory stimuli such as massage and music, as reported in the literature. The data suggest that a specific cosmetic fragrance can have a significant role in enhancing relaxation.


Subject(s)
Detergents/administration & dosage , Lavandula , Odorants , Relaxation , Anxiety/diagnosis , Anxiety/prevention & control , Cognition , Electrocardiography , Electroencephalography , Heart Rate/physiology , Humans , Mathematics , Severity of Illness Index
9.
Int J Neurosci ; 114(8): 933-45, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15527200

ABSTRACT

Depressed (n = 45) and nondepressed (n = 47) mothers were recruited prenatally at an ultrasound clinic. Their urine samples were assayed for cortisol, catecholamines (norepinephrine, epinephrine, dopamine) and serotonin. Their urines were assayed again at the neonatal period, and their newborns' urines were also assayed at that time. The depressed versus the nondepressed mothers showed significantly higher cortisol and norepinephrine and significantly lower dopamine levels across the pre- and postnatal assessments. At the postnatal assessment all levels had decreased except the serotonin levels for both groups. Regression analyses on the mother's postnatal biochemistry with the prenatal biochemistry entered as predictor variables showed highly significant, specific relationships between each of the catecholamines, cortisol, and serotonin. The newborn's biochemistry (except for epinephrine) was higher than the maternal biochemistry. Regression analyses on the neonatal biochemistry with the mother's prenatal biochemistry entered as predictor variables also suggested highly significant, specific relationships. The continuity between the mother's and the newborn's neurotransmitter/ neurohormone profiles and data showing that elevated norepinephrine and cortisol predict to low birthweight and prematurity, respectively, highlight the importance of assessing these levels during pregnancy.


Subject(s)
Depression/urine , Infant, Newborn/urine , Maternal-Fetal Exchange , Mothers/psychology , Pregnancy/urine , Adult , Analysis of Variance , Biochemical Phenomena , Biochemistry , Catecholamines/urine , Female , Humans , Hydrocortisone/urine , Male , Reference Values , Regression Analysis , Serotonin/urine
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