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1.
Rev. biol. trop ; 72(1): e55265, ene.-dic. 2024. tab, graf
Article in English | SaludCR, LILACS | ID: biblio-1559322

ABSTRACT

Abstract Introduction: The Wood Thrush is a migratory bird that has experienced dramatic declines in its populations in recent decades. This species overwinters in forest fragments with intermediate levels of habitat modification in Central America. However, more studies detailing the use of remnant forests through time are needed to elucidate the threats this species faces in the wintering grounds. Objective: To understand the effects of environmental and forest structure variables on the occupancy of Wood Thrush in Northern Costa Rica. Methods: The study area was the Área de Conservación Guanacaste (ACG), located in Northern Costa Rica, in December 2016, and during the 2018-2019 migration season. We estimated Wood Thrush occupancy and detection probability in four locations of ACG (dry forest, cloud forest, and two locations in the wet forest) using single-season occupancy models. We also estimated Wood Thrush occupancy and probability of persistence in different months in three vegetation types (open area, secondary forest, and old-growth forest) in the wet forest of ACG using a multi-season occupancy model approach. Results: Wood Thrush occupancy was best described by precipitation in the four locations of the ACG; the probability of occupancy increased with precipitation. The average occupancy of Wood Thrushes varied with vegetation type: open area with shrubs and forest edge (0.69 ± 0.09), secondary forest (0.46 ± 0.1), and old-growth forest (0.61 ± 0.1). Wood Thrush probability of persistence responded partially to changes in precipitation, with an unexpected increase in persistence when the rainfall continued decreasing in the season. Conclusion: Wood Thrush occupancy was best predicted by changes in precipitation considering a larger spatial scale. Its probability of persistence partially varied with precipitation. An increase in persistence closer to Spring migration might be explained by the start of the breeding season of resident birds, potentially reducing territorial conflicts and conserving energy before migration. The long-term protection of wet forests in Northern Costa Rica is of paramount importance for the conservation of Wood Thrushes in their wintering grounds.


Resumen Introducción: El Zorzal del Bosque es un ave migratoria que ha experimentado caídas dramáticas en sus poblaciones en las últimas décadas. Esta especie pasa el invierno en fragmentos de bosque con niveles intermedios de modificación de hábitat en Centroamérica. Sin embargo, se necesitan más estudios que detallen el uso de los bosques remanentes a lo largo del tiempo para dilucidar las amenazas que enfrenta esta especie en las zonas de invernada. Objetivo: Comprender los efectos de variables ambientales y de estructura del bosque en la ocurrencia del Zorzal del Bosque en el Norte de Costa Rica. Métodos: El área de estudio fue el Área de Conservación Guanacaste (ACG), ubicada en el Norte de Costa Rica, en diciembre de 2016, y en la temporada migratoria 2018-2019. Estimamos la ocurrencia y la probabilidad de detección del Zorzal del Bosque en cuatro ubicaciones de ACG (bosque seco, bosque nuboso y dos ubicaciones en el bosque húmedo) utilizando modelos de ocurrencia de una sola temporada. También estimamos la ocurrencia del Zorzal del Bosque y la probabilidad de persistencia en diferentes meses en tres tipos de vegetación (área abierta, bosque secundario y bosque primario) en el bosque húmedo de ACG utilizando un enfoque de modelo de ocurrencia multi-estacional. Resultados: La ocurrencia del Zorzal del Bosque estuvo mejor descrita por la precipitación en las cuatro localidades del ACG; la probabilidad de ocurrencia aumentó con las precipitaciones. La ocurrencia media de zorzales varió con el tipo de vegetación: área abierta con arbustos y borde de bosque (0.69 ± 0.09), bosque secundario (0.46 ± 0.1) y bosque primario (0.61 ± 0.1). La probabilidad de persistencia del zorzal respondió parcialmente a cambios en la precipitación, con un aumento inesperado en la persistencia cuando las precipitaciones continuaron disminuyendo en la temporada. Conclusión: La ocurrecia del Zorzal del Bosque varió con la precipitación considerando una escala espacial mayor. Su probabilidad de persistencia varió parcialmente con la precipitación. Un aumento en la persistencia más cerca de la migración de primavera podría explicarse por el inicio de la temporada de reproducción de las aves residentes, lo que podría reducir los conflictos territoriales y conservar energía antes de la migración. La protección a largo plazo de los bosques húmedos en el norte de Costa Rica es de suma importancia para la conservación de los Zorzales del Bosque en sus zonas de invernada.


Subject(s)
Animals , Animal Migration , Passeriformes , Seasons , Costa Rica
2.
Am J Dent ; 36(5): 227-232, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37865809

ABSTRACT

PURPOSE: To evaluate staining- and aging-dependent changes in the color and translucency of 3D-printed resin-modified ceramics (RMC). METHODS: Specimens (n= 5 per condition and material) were fabricated from test materials: Permanent Crown Resin (PCR), Crowntec (CT), Vita Enamic (VE) and Tetric CAD (TC). Specimens were stained in wine, coffee, tea, and water (control) and exposed to artificial accelerated aging (AAA). Color measurements were obtained using a spectrophotometer at baseline (T0) and at 3.5 (T1) and 7 (T2) days after immersion. For AAA, measurements were obtained at baseline (T0) and after exposure to controlled irradiance of 150 kJ/m² (T1) and 300 kJ/m² (T2). Mean and standard deviations were calculated on CIEDE2000 color differences (ΔE00), translucency parameter (TP00) and treatment-dependent changes in the translucency parameter (ΔTP0 0). Differences between materials and test conditions were tested by one-way ANOVA (α= 0.05). Results were additionally interpreted using visual color difference thresholds in dentistry ΔE00= 0.8 for the 50:50 perceptibility threshold (PT) and ΔE00= 1.8 for the 50:50 acceptability threshold (AT). ΔTP00 values were interpreted using 5058;50 TPT00= 0.6 and 50:0% TAT00= 2.6. RESULTS: Statistically significant differences were found among the materials when exposed to the different test conditions. At the T0-T1 time interval, the highest color difference was found with wine (0.1-2.2) on all materials except CT, which showed the highest ΔE00 with AAA (2.5). The second highest color differences were obtained upon exposure to AAA (0.2-2.5) and tea (0.5-1.1). The TP00 at baseline ranged from 5.1 to 9.8. Significant differences in ΔTP00 were found among the tested materials and staining/aging conditions, but no significant differences were found among the staining/aging intervals (T0-T1, T0-T2 and T1-T2). CLINICAL SIGNIFICANCE: Staining- and artificial aging-dependent changes of 3D-printed and milled resin modified ceramics used for definitive restorations could represent a challenge in terms of restoration acceptability or dissatisfaction. Staining and aging conditions produced significant color changes, while translucency changes were not significant.


Subject(s)
Ceramics , Tea , Color , Materials Testing , Staining and Labeling , Surface Properties , Printing, Three-Dimensional , Computer-Aided Design
3.
J Immigr Refug Stud ; 19(4): 456-471, 2021.
Article in English | MEDLINE | ID: mdl-35002571

ABSTRACT

Undocumented immigrants often experience multiple chronic stressors that over time can increase health risk. This qualitative study used data from 7 focus groups and 15 key informant interviews to identify relevant protective factors to the heath of undocumented immigrants in the U.S. Findings showed that at the individual level, undocumented immigrants rely primarily on motivation to cope with adversity, while also relying on family support and community cohesion at the interpersonal level. At the policy level, safe neighborhoods and non-stigmatizing environments, protection from abuse/exploitation, and activism were identified as protective factors. English proficiency was also identified as important.

4.
J Electrochem Soc ; 168(8)2021 Aug.
Article in English | MEDLINE | ID: mdl-36311278

ABSTRACT

Soil health is a complex phenomenon that reflects the ability of soil to support both plant growth and other ecosystem functions. To our knowledge, research on extracellular electron transfer processes in soil environments is limited and could provide novel knowledge and new ways of monitoring soil health. Electrochemical activities in the soil can be studied by inserting inert electrodes. Once the electrode is polarized to a favorable potential, nearby microorganisms attach to the electrodes and grow as biofilms. Biofilms are a major part of the soil and play critical roles in microbial activity and community dynamics. Our work aims to investigate the electrochemical behavior of healthy and unhealthy soils using chronoamperometry and cyclic voltammetry. We developed a bioelectrochemical soil reactor for electrochemical measurements using healthy and unhealthy soils taken from the Cook Agronomy Farm Long-Term Agroecological Research site; the soils showed similar physical and chemical characteristics, but there was higher plant growth where the healthy soil was taken. Using carbon cloth electrodes installed in these soil reactors, we explored the electrochemical signals in these two soils. First, we measured redox variations by depth and found that reducing conditions were prevalent in healthy soils. Current measurements showed distinct differences between healthy and unhealthy soils. Scanning electron microscopy images showed the presence of microbes attached to the electrode for healthy soil but not for unhealthy soil. Glucose addition stimulated current in both soil types and caused differences in cyclic voltammograms between the two soil types to converge. Our work demonstrates that we can use current as a proxy for microbial metabolic activity to distinguish healthy and unhealthy soil.

5.
Seizure ; 83: 1-4, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33075670

ABSTRACT

PURPOSE: Our objective is to describe the most prevalent electroencephalographic findings in COVID-19 hospitalized patients, and to determine possible predictors of mortality including EEG and clinical variables. METHODS: A multicentric prospective observational study in patients with COVID-19 requiring EEG during hospitalization. RESULTS: We found 94 EEG from 62 patients (55 % men, mean age 59.7 ± 17.8 years) were analyzed. Most frequent comorbidity was cardiac (52 %), followed by metabolic (45 %) and CNS disease (39 %). Patients required ICU management by 60 %, with a mortality of 27 % in the whole cohort. The most frequent EEG finding was generalized continuous slow-wave activity (66 %). Epileptic activity was observed in 19 % including non-convulsive status epilepticus, seizures and interictal epileptiform discharges. Periodic patterns were observed in 3 patients (3.2 %). Multivariate analysis found that cancer comorbidity and requiring an EEG during the third week of evolution portended a higher risk of mortality CONCLUSION: We observed that the most prevalent EEG finding in this cohort was generalized continuous slow-wave activity, while epileptic activity was observed in less than 20 % of the cases. Mortality risk factors were comorbidity with cancer and requiring an EEG during the third week of evolution, possibly related to the hyperinflammatory state.


Subject(s)
COVID-19/mortality , Electroencephalography , SARS-CoV-2/pathogenicity , Seizures/physiopathology , Adult , Aged , Aged, 80 and over , COVID-19/diagnosis , COVID-19/physiopathology , Electroencephalography/methods , Epilepsy/physiopathology , Epilepsy/virology , Female , Hospitalization/statistics & numerical data , Humans , Inpatients , Male , Middle Aged , Prognosis , Seizures/virology , Status Epilepticus/mortality , Status Epilepticus/physiopathology , Status Epilepticus/virology
6.
J Esthet Restor Dent ; 31(5): 465-470, 2019 09.
Article in English | MEDLINE | ID: mdl-31095870

ABSTRACT

OBJECTIVE: To evaluate the instrumental and visual color adjustment potential (CAP-I, CAP-V), of resin composites. METHODS: Resin composites tested were Omnichroma, Filtek Supreme Ultra, TPH Spectra, Herculite Ultra, and Tetric EvoCeram. Two types of specimens, "dual" and "single" were evaluated. For dual specimens, class I preparations (4 mm-diameter, 2 mm-depth), were created in denture teeth and restored with test resin composites. For single specimens, replications of denture teeth were created using the test resin composites (n = 5) and compared with unrestored denture teeth. Reflectance values were obtained using a spectroradiometer. CAP-I and CAP-V were calculated. Fisher PLSD intervals for comparison of means were calculated at the 0.05 level of significance. RESULTS: CAP-I ranged between 0.02 and 0.67. The Fisher PLSD interval for comparisons between single/dual color differences was 0.09 (P < .0001, power 1.0) and for comparisons between materials and shades 0.18 and 0.33, respectively (P < .0001, power 1.0). CAP-V ranged between 0.16 and 0.60. The Fisher PLSD interval for comparisons between single/dual visual color differences was 0.05 (P < .0001, power 1.0) and 0.08 and 0.14 for comparisons between materials and shades, respectively (P < .0001, except Herculite Ultra-Tetric EvoCeram and certain shade pairs). CONCLUSIONS: Instrumental color differences and visual rating of single specimens were the greatest for Omnichroma, indicating the largest mismatch, while the instrumental and visual color differences of dual specimens were the smallest. Omnichroma had the most pronounced CAP-I followed by Tetric EvoCeram>TPH Spectra = Filtek Supreme Ultra >Herculite Ultra. Similarly, Omnichroma exhibited the most pronounced CAP-V followed by Tetric EvoCeram>TPH Spectra = Herculite Ultra = Filtek Supreme Ultra. CLINICAL SIGNIFICANCE: Resin composites with pronounced CAP blends with surrounding enamel and dentin, resulting in reduced color differences and therefore improving the esthetic appearance of the restoration, simplifying the shade matching and compensating for any color mismatch.


Subject(s)
Composite Resins , Color , Materials Testing
7.
J Esthet Restor Dent ; 29(5): 352-355, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28734081

ABSTRACT

OBJECTIVE: To evaluate in vitro the fluorescence properties of extracted human teeth whitened with 40% hydrogen peroxide. MATERIALS AND METHODS: A total of 28 extracted human teeth were pumiced for 1 minute using a low-speed dental handpiece and a disposable rubber cup. Pre-whitening fluorescence measurements (T0), maximum excitation (Exmax ), maximum emission (Emmax ), and maximum intensity (Imax 108 ), were performed using a spectrofluorometer. After T0 measurements, the teeth were whitened using the in-office method with 40% hydrogen peroxide, three times for 20 minutes. The fluorescence parameters were measured under the same conditions 7 and 14 days after bleaching (T1 and T2, respectively). RESULTS: Exmax exhibited a broader range 7 days after whitening and decreased after 14 days. The Emmax and Imax 108 displayed a narrower range after whitening. The mean Exmax differed significantly between the time points (F = 20.09. P < .001). The corresponding analysis for the mean Emmax differed significantly between the time points (F = 16.69, P < .001). The same was true for the mean Imax 108 (F = 9.69, P < .001). CONCLUSIONS: Within the limitations of this study, whitening provoked statistically significant changes in fluorescence of the intact teeth in vitro. CLINICAL SIGNIFICANCE: The appearance of human teeth and dental materials and their changes upon aging and exposure to different agents (staining, whitening) is a topic of great relevance to esthetic dentistry. While some appearance parameters, such as color, translucency, and gloss, have been thoroughly studied, fluorescence and its influence on overall tooth appearance is still not well understood, yet it has influenced the development of fluorescence emitting restorative materials.


Subject(s)
Fluorescence , Hydrogen Peroxide/chemistry , Tooth Bleaching Agents/chemistry , Tooth Discoloration/prevention & control , Humans , In Vitro Techniques
8.
Anim Cogn ; 18(5): 1113-23, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26116045

ABSTRACT

Songbirds have been traditionally classified into close-ended or open-ended learning species according to the length of the sensitive period during which birds are able to memorize new vocalizations. Closed-ended learners are generally not capable of changing their song after the first year of life, while open-ended learners show song plasticity as adults. A few Turdus species have been suggested to be open-ended learners, but no long-term study has been conducted to investigate their song plasticity over time. We analyzed the songs of clay-colored thrushes, T. grayi, over four successive breeding seasons to assess song plasticity in their syllable repertoires within and between breeding seasons. A total of 16,262 syllables were classified through visual inspection of spectrograms and multidimensional scaling analysis based on spectrogram correlations. On average, 563 ± 153 (SD) syllables per male per breeding season were analyzed. Male repertoire size was 9-20 syllable types. Males were capable of modifying their syllable repertoire between the initial and final periods of the breeding season. Song plasticity within breeding seasons may be associated with imitation between neighboring males, suggesting song learning in males that were ≥2 years old. This short-term plasticity is not enough, however, to explain the high proportion of change (mean = 65 % syllable types) in repertoire composition between breeding seasons in adult males. Song plasticity resulting from annual changes in repertoire composition could be explained by open-ended learning, but another mechanism, extended memory and re-expression, could also explain long-term plasticity. Experimental studies controlling the acoustic environment are needed to determine which mechanism is responsible for such a high level of song plasticity.


Subject(s)
Learning , Songbirds/physiology , Vocalization, Animal/physiology , Animals , Male , Memory , Reproduction , Seasons , Sound Spectrography , Time Factors
9.
Psychophysiology ; 45(6): 926-35, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18823427

ABSTRACT

Impaired P50 gating is thought to reflect a core deficit in schizophrenia, but the relevant neural network is not well understood. The present study used EEG and MEG to assess sensory gating and volumetric MRI to measure hippocampal volume to investigate relationships between them in 22 normal controls and 22 patients with schizophrenia. In the schizophrenia group, anterior but not posterior hippocampal volume was smaller, and both the P50 and M50 gating ratios were larger (worse) than in controls. Independent of group, left-hemisphere M50 gating ratio correlated negatively with left anterior hippocampal volume, and right-hemisphere M50 gating ratio correlated negatively with right anterior hippocampal volume. Schizophrenia diagnosis predicted M50 gating independent of hippocampal volume. These results are consistent with the finding that hippocampus is a critical part of a fronto-temporal circuit involved in auditory gating.


Subject(s)
Auditory Perception/physiology , Hippocampus/pathology , Schizophrenia/pathology , Schizophrenic Psychology , Acoustic Stimulation , Adult , Antipsychotic Agents/therapeutic use , Data Interpretation, Statistical , Female , Functional Laterality/physiology , Humans , Magnetic Resonance Imaging , Magnetoencephalography , Male , Psychiatric Status Rating Scales , Schizophrenia/drug therapy , Sound Localization/physiology
10.
Eukaryot Cell ; 7(4): 619-29, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18245278

ABSTRACT

Maintenance of cell morphology is essential for normal cell function. For eukaryotic cells, a growing body of recent evidence highlights a close interdependence between mitochondrial function, the cytoskeleton, and cell cycle control mechanisms; however, the molecular details of this interconnection are still not completely understood. We have identified a novel protein, Bot1p, in the fission yeast Schizosaccharomyces pombe. The bot1 gene is essential for cell viability. bot1Delta mutant cells expressing lower levels of Bot1p display altered cell size and cell morphology and a disrupted actin cytoskeleton. Bot1p localizes to the mitochondria in live cells and cofractionates with purified mitochondrial ribosomes. Reduced levels of Bot1p lead to mitochondrial fragmentation, decreased mitochondrial protein translation, and a corresponding decrease in cell respiration. Overexpression of Bot1p results in cell cycle delay, with increased cell size and cell length and enhanced cell respiration rate. Our results show that Bot1p has a novel function in the control of cell respiration by acting on the mitochondrial protein synthesis machinery. Our observations also indicate that in fission yeast, alterations of mitochondrial function are linked to changes in cell cycle and cell morphology control mechanisms.


Subject(s)
Mitochondria/physiology , Mitochondrial Proteins/metabolism , Protein Biosynthesis , Schizosaccharomyces pombe Proteins/metabolism , Schizosaccharomyces/cytology , Amino Acid Sequence , Microbial Viability , Mitochondrial Proteins/genetics , Molecular Sequence Data , Schizosaccharomyces/physiology , Schizosaccharomyces pombe Proteins/genetics , Sequence Alignment
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