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1.
Eur Phys J C Part Fields ; 79(11): 978, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31885491

RESUMEN

The GERmanium Detector Array (Gerda) is a low background experiment located at the Laboratori Nazionali del Gran Sasso in Italy, which searches for neutrinoless double-beta decay of 76 Ge into 76 Se+2e - . Gerda has been conceived in two phases. Phase II, which started in December 2015, features several novelties including 30 new 76Ge enriched detectors. These were manufactured according to the Broad Energy Germanium (BEGe) detector design that has a better background discrimination capability and energy resolution compared to formerly widely-used types. Prior to their installation, the new BEGe detectors were mounted in vacuum cryostats and characterized in detail in the Hades underground laboratory in Belgium. This paper describes the properties and the overall performance of these detectors during operation in vacuum. The characterization campaign provided not only direct input for Gerda Phase II data collection and analyses, but also allowed to study detector phenomena, detector correlations as well as to test the accuracy of pulse shape simulation codes.

2.
Phys Rev Lett ; 120(13): 132501, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29694201

RESUMEN

The CUORE experiment, a ton-scale cryogenic bolometer array, recently began operation at the Laboratori Nazionali del Gran Sasso in Italy. The array represents a significant advancement in this technology, and in this work we apply it for the first time to a high-sensitivity search for a lepton-number-violating process: ^{130}Te neutrinoless double-beta decay. Examining a total TeO_{2} exposure of 86.3 kg yr, characterized by an effective energy resolution of (7.7±0.5) keV FWHM and a background in the region of interest of (0.014±0.002) counts/(keV kg yr), we find no evidence for neutrinoless double-beta decay. Including systematic uncertainties, we place a lower limit on the decay half-life of T_{1/2}^{0ν}(^{130}Te)>1.3×10^{25} yr (90% C.L.); the median statistical sensitivity of this search is 7.0×10^{24} yr. Combining this result with those of two earlier experiments, Cuoricino and CUORE-0, we find T_{1/2}^{0ν}(^{130}Te)>1.5×10^{25} yr (90% C.L.), which is the most stringent limit to date on this decay. Interpreting this result as a limit on the effective Majorana neutrino mass, we find m_{ßß}<(110-520) meV, where the range reflects the nuclear matrix element estimates employed.

3.
Appl Radiat Isot ; 87: 331-5, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24331853

RESUMEN

The dead-layer uniformity of the top surface of two high purity germanium detectors has been studied using a novel automated scanning set-up that allows a fine-grained topography of a detector's top and lateral surfaces. Comparisons between measurements and Monte Carlo simulations allowed implementation of a dead-layer variation into the detector model, which reproduces the measurements results. The effect of the non-uniform dead-layer on activity determinations based on low-energy γ-rays (i.e. below ~100 keV) has been determined to be of the order of 10% or more.

4.
Phys Rev Lett ; 111(12): 122503, 2013 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-24093254

RESUMEN

Neutrinoless double beta decay is a process that violates lepton number conservation. It is predicted to occur in extensions of the standard model of particle physics. This Letter reports the results from phase I of the Germanium Detector Array (GERDA) experiment at the Gran Sasso Laboratory (Italy) searching for neutrinoless double beta decay of the isotope (76)Ge. Data considered in the present analysis have been collected between November 2011 and May 2013 with a total exposure of 21.6 kg yr. A blind analysis is performed. The background index is about 1 × 10(-2) counts/(keV kg yr) after pulse shape discrimination. No signal is observed and a lower limit is derived for the half-life of neutrinoless double beta decay of (76)Ge, T(1/2)(0ν) >2.1 × 10(25) yr (90% C.L.). The combination with the results from the previous experiments with (76)Ge yields T(1/2)(0ν)>3.0 × 10(25) yr (90% C.L.).

5.
Rev Soc Bras Med Trop ; 41(5): 459-63, 2008.
Artículo en Portugués | MEDLINE | ID: mdl-19009186

RESUMEN

The aim of our study was to perform molecular typing on 25 clinical samples of Candida spp that were isolated from children with candidemia who were hospitalized in the neonatal intensive care unit of a university hospital between 1998 and 2006. Demographic and clinical data were obtained from the medical records to ascertain the clinical and epidemiological characteristics. Yeast identification was done using conventional methods and susceptibility to antifungals was assessed using a microdilution method. The genetic profile was determined using the RAPD-PCR technique. Candida albicans (11; 44%) and Candida parapsilosis (10; 40%) were the species most frequently isolated. Seventeen (68%) of the newborns weighed less than 1,500 g. Prematurity (92%) and use of a central venous catheter (100%) were the risk conditions with greatest association. Nineteen patients (76%) died. Only one strain of Candida parapsilosis showed dose-dependent sensitivity to fluconazole. Molecular analysis showed 11 distinct genetic patterns. An epidemiological relationship was seen in only two cases, thus suggesting the same source of infection.


Asunto(s)
Antifúngicos/farmacología , Candida/clasificación , Fluconazol/farmacología , Fungemia/microbiología , Brasil , Candida/efectos de los fármacos , Candida/genética , ADN de Hongos/análisis , Femenino , Hospitales Públicos , Humanos , Lactante , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino , Pruebas de Sensibilidad Microbiana , Técnicas de Tipificación Micológica , Técnica del ADN Polimorfo Amplificado Aleatorio , Estudios Retrospectivos , Factores de Riesgo
6.
Rev. Soc. Bras. Med. Trop ; 41(5): 459-463, set.-out. 2008. ilus, tab
Artículo en Portugués | LILACS | ID: lil-496709

RESUMEN

O objetivo de nosso estudo foi realizar tipagem molecular de 25 amostras clínicas de Candida spp, isoladas de crianças com candidemia, internadas na unidade de terapia intensiva neonatal de um Hospital Universitário entre 1998 a 2006. Dados demográficos e clínicos foram obtidos de prontuários para conhecimento dos aspectos clínicos e epidemiológicos. Identificação das leveduras foi feita por método convencional e a susceptibilidade antifúngica por método de microdiluição. O perfil genético foi determinado pela técnica de RAPD-PCR. Candida albicans (11; 44 por cento) e Candida parapsilosis (10; 40 por cento) foram as mais isoladas. Dezessete (68 por cento) dos recém-nascidos tinham peso inferior a 1.500g. Prematuridade (92 por cento), uso de cateter venoso central (100 por cento), foram as condições de risco mais associados. Dezenove (76 por cento) pacientes foram a óbito. Apenas uma cepa de Candida parapsilosis, mostrou ser sensível dose dependente ao fluconazol. Na análise molecular, foram observados 11 padrões genéticos distintos. Somente em dois casos foi observada relação epidemiológica, sugerindo mesma fonte de infecção.


The aim of our study was to perform molecular typing on 25 clinical samples of Candida spp that were isolated from children with candidemia who were hospitalized in the neonatal intensive care unit of a university hospital between 1998 and 2006. Demographic and clinical data were obtained from the medical records to ascertain the clinical and epidemiological characteristics. Yeast identification was done using conventional methods and susceptibility to antifungals was assessed using a microdilution method. The genetic profile was determined using the RAPD-PCR technique. Candida albicans (11; 44 percent) and Candida parapsilosis (10; 40 percent) were the species most frequently isolated. Seventeen (68 percent) of the newborns weighed less than 1,500g. Prematurity (92 percent) and use of a central venous catheter (100 percent) were the risk conditions with greatest association. Nineteen patients (76 percent) died. Only one strain of Candida parapsilosis showed dose-dependent sensitivity to fluconazole. Molecular analysis showed 11 distinct genetic patterns. An epidemiological relationship was seen in only two cases, thus suggesting the same source of infection.


Asunto(s)
Femenino , Humanos , Lactante , Recién Nacido , Masculino , Antifúngicos/farmacología , Candida/clasificación , Fluconazol/farmacología , Fungemia/microbiología , Brasil , Candida/efectos de los fármacos , Candida/genética , ADN de Hongos/análisis , Hospitales Públicos , Unidades de Cuidado Intensivo Neonatal , Pruebas de Sensibilidad Microbiana , Técnicas de Tipificación Micológica , Técnica del ADN Polimorfo Amplificado Aleatorio , Estudios Retrospectivos , Factores de Riesgo
7.
Naunyn Schmiedebergs Arch Pharmacol ; 376(5): 331-9, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18064439

RESUMEN

This study was designed to evaluate the mechanism by which propofol modifies leukocyte production of nitric oxide (NO) in humans. In vitro experiments used whole blood from healthy volunteers (n = 10 samples/experiment). Ex vivo experiments studied the effects of an intravenous dose of 2.5 mg propofol per kilogram body weight followed by intravenous infusion of 4 mg kg(-1) h(-1) in surgical patients in ASA class I or II (n = 20). In whole blood, neutrophils and plasma, we measured NO production and the activities of the enzymes nitric oxide synthase [inducible (iNOS) and constitutive (cNOS)] and cyclooxygenase [constitutive (COX-1) and inducible (COX-2)]. Concentrations of interleukins (IL-1beta, IL-6, and IL-10) and tumor necrosis factor-alpha (TNFalpha) were measured in plasma. In blood from healthy donors, propofol increased NO production and cNOS activity. The concentration of propofol that increased NO production by 50% (EC(50)) was 23.5 microM, and the EC(50) of propofol for cNOS was 18.6 microM. In blood from surgical patients, propofol increased NO production by 52% and cNOS activity by 57%. Propofol inhibited iNOS activity in vitro; the concentration that reduced activity by 50% (IC(50)) was 19.9 microM. In surgical patients propofol inhibited iNOS activity by 53%. COX-1 and COX-2 activities were inhibited in vitro (IC(50) 32.6 and 187 microM, respectively) and in surgical patients (53 and 81% inhibition, respectively). Plasma concentrations of IL-1beta, IL-6, and TNFalpha were significantly reduced in surgical patients (32, 23, and 21% inhibition, respectively). None of these parameters were modified in a group of patients (n = 10) anesthetized with sevoflurane. We conclude that propofol stimulated constitutive NO production and inhibited inducible NO production, possibly by curtailing the stimulation of iNOS by inflammatory mediators in surgical patients.


Asunto(s)
Anestésicos Intravenosos/farmacología , Leucocitos/efectos de los fármacos , Óxido Nítrico/biosíntesis , Propofol/farmacología , Adulto , Anestésicos Intravenosos/administración & dosificación , Ciclooxigenasa 1/efectos de los fármacos , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 2/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Técnicas In Vitro , Infusiones Intravenosas , Interleucinas/metabolismo , Leucocitos/metabolismo , Masculino , Persona de Mediana Edad , Óxido Nítrico Sintasa de Tipo I/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo I/metabolismo , Óxido Nítrico Sintasa de Tipo II/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo II/metabolismo , Propofol/administración & dosificación , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo
8.
Mycol Res ; 110(Pt 6): 686-96, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16769209

RESUMEN

Derivatives of pyrazolo[1,5-a][1, 3, 5]triazine-2,4-dione,pyrazolo[1,5-c][1, 3, 5]thiadiazine-2-one, pyrazolo[3,4-d][1, 3]thiazine-4-one, and pyrazolo[3,4-d][1, 3]thiazine-4-thione were screened for antifungal activity against the causal agent of rice blast disease, Magnaporthe grisea. The compounds were tested at doses ranging from 10 to 200mugml(-1), using the commercial fungicide tricyclazole as reference compound. All triazine derivatives inhibited the growth and pigmentation of the mycelia less effectively than tricyclazole. The thiadiazine derivatives proved to be more effective than their triazine counterparts, but only 4-(butylimino)-7-methylpyrazolo[1,5-c][1,3,5]thiadiazine-2-one (2h) and 4-(cyclohexylimino)-7-methylpyrazolo[1,5-c][1,3,5]thiadiazine-2-one (2j) were more effective than tricyclazole. Pyrazolo[3,4-d][1,3]thiazine-4-one derivatives were active only at the highest doses, whereas members of the pyrazolo[3,4-d][1,3]thiazine-4-thione series inhibited fungal growth at the lowest concentrations used, at which tricyclazole had no effect. A dose-dependent mechanism might be responsible for this effect, with lipophilicity as the governing factor. Within a given set, the presence of a cyclohexyl or an n-butyl group generally increased antifungal activity, with respect to both growth inhibition and cell de-pigmentation of the mycelium, suggesting that a higher lipophilicity might improve transport inside the cells. SEM and TEM of M. grisea hyphae showed that treatment with the most active substance (2h) caused significant ultrastructural effects, particularly on the endomembrane system, suggesting a mechanism of action similar to that of most azole fungicides. Dissimilarities were also observed, with no alterations of the cell wall evident. In conclusion, several compounds showed greater inhibition than tricyclazole, and therefore provide useful new chemistry for control of M. grisea infections.


Asunto(s)
Antifúngicos/farmacología , Azoles/farmacología , Magnaporthe/efectos de los fármacos , Azoles/síntesis química , Azoles/química , Medios de Cultivo , Magnaporthe/crecimiento & desarrollo , Magnaporthe/ultraestructura , Pruebas de Sensibilidad Microbiana/métodos , Microscopía Electrónica de Rastreo , Oryza/microbiología , Enfermedades de las Plantas/microbiología , Pirazoles/farmacología , Tiazoles/farmacología
9.
Mycopathologia ; 160(1): 85-91, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16160773

RESUMEN

In this work extracts from roots of the common vegetable Cichorium intybus L., highly appreciated for its bitter taste, were studied to investigate their possible biological activity on fungi from a variety of ecological environments: some are parasites on plants (phytopathogens) or of animals and humans (zoophilic and anthropophilic dermatophytes), others live on the soil and only seldom parasitize animals (geophilic dermatophytes). The extracts were ineffective on geophilic species and on tested phytopathogens, with the exception of Pythium ultimum, whereas they inhibited the growth of zoophilic and anthropophilic dermatophytes, in particular Trichophyton tonsurans var. sulfureum, whose treatment caused morphological anomalies, here observed by scanning electron microscopy. This behaviour is discussed on the basis of the presence in the chicory extract of the two main sesquiterpene lactones, 8-deoxylactucin and 11 beta,13-dihydrolactucin.


Asunto(s)
Antifúngicos , Cichorium intybus , Hongos/efectos de los fármacos , Animales , Arthrodermataceae/efectos de los fármacos , Arthrodermataceae/crecimiento & desarrollo , Hongos/crecimiento & desarrollo , Humanos , Extractos Vegetales , Raíces de Plantas
10.
Protoplasma ; 225(1-2): 57-65, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15868213

RESUMEN

The essential oil extracted by steam distillation from the capitula of Indian Tagetes patula, Asteraceae, was evaluated for its antifungal properties and analyzed by gas chromatography and gas chromatography-mass spectrometry. Thirty compounds were identified, representing 89.1% of the total detected. The main components were piperitone (24.74%), piperitenone (22.93%), terpinolene (7.8%), dihydro tagetone (4.91%), cis-tagetone (4.62%), limonene (4.52%), and allo-ocimene (3.66%). The oil exerted a good antifungal activity against two phytopathogenic fungi, Botrytis cinerea and Penicillium digitatum, providing complete growth inhibition at 10 microl/ml and 1.25 microl/ml, respectively. The contribution of the two main compounds, piperitone and piperitenone, to the antifungal efficacy was also evaluated and ultrastructural modifications in mycelia were observed via electron microscopy, evidencing large alterations in hyphal morphology and a multisite mechanism of action.


Asunto(s)
Antifúngicos/química , Antifúngicos/farmacología , Aceites de Plantas/química , Aceites de Plantas/farmacología , Tagetes/química , Antifúngicos/aislamiento & purificación , Botrytis/efectos de los fármacos , Botrytis/ultraestructura , Cromatografía de Gases y Espectrometría de Masas , India , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Penicillium/efectos de los fármacos , Aceites de Plantas/aislamiento & purificación
11.
Nat Prod Res ; 19(3): 295-303, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15702645

RESUMEN

The biovariability of Hypericum perforatum L. (St. John's Wort) grown wild in Calabria and Sardinia (Italy) was reported with the aim to characterize the species through the isolation, detection, and quantitative evaluations of chemical markers (hypericin, quercetin, rutin) by HPLC analysis. Antioxidant activity of the methanolic H. perforatum extracts showed that the Calabrian samples were more active than those from Sardinia. The antibacterial activity evidenced the best performance on the gram positive bacteria with a MIC value of 50 microg/mL. Moreover, antifungal activity of all the extracts was also tested which showed interesting results particularly on the phytopathogene fungus P. ultimum. The variability shown by the samples could be attributed to environmental factors such as chemical-physical properties, composition of the soil, geographical coordinate, altitude, and solar exposure. The phytochemical analysis and the biological activity data suggested a possible use of H. perforatum extracts in the alimentary, cosmetic, and pharmaceutical fields.


Asunto(s)
Hypericum/química , Perileno/análogos & derivados , Perileno/aislamiento & purificación , Perileno/farmacología , Quercetina/aislamiento & purificación , Quercetina/farmacología , Rutina/aislamiento & purificación , Rutina/farmacología , Antracenos , Cromatografía Líquida de Alta Presión , Metanol/química , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Solventes/química
12.
Microbiol Res ; 159(3): 295-304, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15462529

RESUMEN

Methanol extract, obtained from Tagetes patula plant, was assayed against three phytopathogenic fungi: Botrytis cinerea, Fusarium moniliforme and Pythium ultimum. The antifungal activity was tested both in the dark and in the light, using two different lighting systems. The data showed that the extract proved to have a dose-dependent activity on all the fungi with a marked difference between treatments in the light than in the dark. Good growth inhibition was observed in fungi only when these were treated with the highest dose of the extract and irradiated, whereas the same dose gave only a modest inhibition when the experiment was conducted in the dark. At 5 and 10 microg/ml in the dark, growth increased. The results indicated that the presence of a luminous source enhances the antifungal activity, with small differences between UV-A and solar spectrum light. SEM and TEM observations on Pythium ultimum revealed that the Tagetes patula extract induced alterations on cell fungal membranes with a photoactivation mechanism possibly involving the production of free radicals and leading to a premature aging of the mycelium.


Asunto(s)
Antifúngicos/farmacología , Botrytis/efectos de los fármacos , Fusarium/efectos de los fármacos , Extractos Vegetales/farmacología , Pythium/efectos de los fármacos , Tagetes/química , Botrytis/ultraestructura , Oscuridad , Fusarium/ultraestructura , Luz , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Enfermedades de las Plantas/microbiología , Pythium/ultraestructura , Rayos Ultravioleta
13.
Mycopathologia ; 153(3): 129-32, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-11998873

RESUMEN

The antifungal activity of five new synthetic compounds was evaluated on two dermatophytes: Epidermophyton floccosum and Trichophyton rubrum. The data showed that the imidazo-pyrazole and pyrazolo-thiazoles were not particularly effective, while the two pyrazole-thiocyanates proved highly active on both fungi. The most active 5-amino-3-methyl-1-phenylpyrazolo-4-thiocyanate was chosen to perform SEM and TEM morphological studies on both fungi. Both SEM and TEM observations revealed interesting alterations on the two dermatophytes, particularly involving the endomembrane system.


Asunto(s)
Antifúngicos/farmacología , Epidermophyton/efectos de los fármacos , Pirazoles/farmacología , Tiocianatos/farmacología , Trichophyton/efectos de los fármacos , Antifúngicos/química , Relación Dosis-Respuesta a Droga , Epidermophyton/ultraestructura , Microscopía Electrónica de Rastreo , Estructura Molecular , Pirazoles/química , Tiocianatos/química , Trichophyton/ultraestructura
14.
Braz J Biol ; 61(2): 323-7, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11514901

RESUMEN

Three options of water temperatures in a thermal gradient that changed from 22 to 35 degrees C were offered to Pantanal caiman (Caiman croocodilus yacare) hatchlings. Animals from two nests were submitted to temperatures during 19 days (Nest 1 -- 20 caimans caught in the nature hours after hatching), corresponding to 1 to 7 observations periods, and 13 days (Nest 2 -- 20 animals obtained by artificial incubation) relative to observation period 8. Caimans remain fasting during experimental period. Hatchlings were allocated in a enclosure containing three styrofoam boxes (120 L) disposed side by side enclosed by wire netting and filled with water to the top. Thus, the animals were free to access the boxes, which temperatures were changed at the end of each observation period to avoid position effects. Air temperature was keep close to 22 degrees C by air conditioning and water temperature was controlled by thermostats. The trial was divided in three phases determined by elimination of the less frequented temperature and its substitution by another temperature. In a first phase of the experiment that contained 1, 2 and 3 observation periods, the thermostats were regulated to 22 degrees C (BoxD), 26 degrees C (BxC) and 32 degrees C (BxA). In phase 2 to 26 degrees C, 29.5 degrees C (BxB) and 32 degrees C, including 4, 5 and 6 periods. In the third phase that included 7 and 8 periods, the thermostats were adjusted to 29.5 degrees C, 32 degrees C and 35 degrees C (BxE). The number of caimans in each box was recorded two to three times a day (8:00, 14:00 and 17:00h) before pointed water temperature. Mean water temperatures (+ standard deviation) and respective caiman frequency means by box/temperature were: Phase 1 (BxD/22.3 +/- 1.2 degrees C - 10.3%; BxC/27.0 +/- 2.4 degrees C - 32.0% and BxA/31.2 +/- 1.1 degrees C - 57.6%); Phase 2 (BxC/26.6 +/- 2.8 degrees C - 13.3%; BxB/29.3 +/- 2.2 degrees C - 27.7% and BxA/31.3 +/- 1.2 degrees C - 59.0%) and Phase 3 (BxB/29.5 +/- 3.6 degrees C - 23.7%; BxA/31.0 +/- 2.2 degrees C - 31.9 and BxE/34.0 +/- 2.2 degrees C - 44.4%). Observing that in the phases 1 and 2 the box with hottest water (CxA) was more frequented. In the phase 3, the difference between higher and smaller frequency straiten to 20.7%, in relation to almost 46.5% in phases 1 and 2, indicating that water temperatures between 29.5 and 35 degrees C resulted in body temperatures more next to the comfort zone, in the experimental conditions.


Asunto(s)
Caimanes y Cocodrilos/fisiología , Animales Recién Nacidos/fisiología , Conducta Animal/fisiología , Temperatura , Animales
15.
Rev. bras. biol ; 61(2): 323-327, May 2001.
Artículo en Inglés | LILACS | ID: lil-298649

RESUMEN

Three options of water temperatures in a thermal gradient that changed from 22 to 35 C were offered to Pantanal caiman (Caiman croocodilus yacare) hatchlings. Animals from two nests were submitted to temperatures during 19 days (Nest 1 - 20 caimans caught in the nature hours after hatching), corresponding to 1 to 7 observations periods, and 13 days (Nest 2 - 20 animals obtained by artificial incubation) relative to observation period 8. Caimans remain fasting during experimental period. Hatchlings were allocated in a enclosure containing three styrofoam boxes (120 L) disposed side by side enclosed by wire netting and filled with water to the top. Thus, the animals were free to access the boxes, which temperatures were changed at the end of each observation period to avoid position effects. Air temperature was keep close to 22 C by air conditioning and water temperature was controlled by thermostats. The trial was divided in three phases determined by elimination of the less frequented temperature and its substitution by another temperature. In a first phase of the experiment that contained 1, 2 and 3 observation periods, the thermostats were regulated to 22 C (BoxD), 26 C (BxC) and 32 C (BxA). In phase 2 to 26 C, 29.5 C (BxB) and 32 C, including 4, 5 and 6 periods. In the third phase that included 7 and 8 periods, the thermostats were adjusted to 29.5 C, 32 C and 35 C (BxE). The number of caimans in each box was recorded two to three times a day (8:00, 14:00 and 17:00h) before pointed water temperature. Mean water temperatures (+ standard deviation) and respective caiman frequency means by box/temperature were: Phase 1 (BxD/22.3 1.2 C - 10.3 percent; BxC/27.0 2.4 C - 32.0 percent and BxA/31.2 1.1 C - 57.6 percent); Phase 2 (BxC/26.6 2.8 C - 13.3 percent; BxB/29.3 2.2 C - 27.7 percent and BxA/31.3 1.2 C - 59.0 percent) and Phase 3 (BxB/29.5 3.6 C - 23.7 percent; BxA/31.0 2.2 C - 31.9 and BxE/34.0 2.2 C - 44.4 percent). Observing that in the phases 1 and 2 the box with hottest water (CxA) was more frequented. In the phase 3, the difference between higher and smaller frequency straiten to 20.7 percent, in relation to almost 46.5 percent in phases 1 and 2, indicating that water temperatures between 29.5 and 35 C resulted in body temperatures more next to the comfort zone, in the experimental conditions


Asunto(s)
Animales , Caimanes y Cocodrilos/fisiología , Animales Recién Nacidos/fisiología , Conducta Animal/fisiología , Temperatura
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