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1.
J Acoust Soc Am ; 152(1): 295, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35931542

RESUMO

Application of a kurtosis correction to frequency-weighted sound exposure level (SEL) improved predictions of risk of hearing damage in humans and terrestrial mammals for sound exposures with different degrees of impulsiveness. To assess whether kurtosis corrections may lead to improved predictions for marine mammals, corrections were applied to temporary threshold shift (TTS) growth measurements for harbor porpoises (Phocoena phocoena) exposed to different sounds. Kurtosis-corrected frequency-weighted SEL predicted accurately the growth of low levels of TTS (TTS1-4 < 10 dB) for intermittent sounds with short (1-13 s) silence intervals but was not consistent with frequency-weighted SEL data for continuous sound exposures.


Assuntos
Phocoena , Estimulação Acústica , Animais , Fadiga Auditiva , Limiar Auditivo , Audição , Humanos , Ruído/efeitos adversos
2.
Neuroimage ; 223: 117383, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32949710

RESUMO

Resting state fMRI (rsfMRI) is frequently used to study brain function, including in clinical populations. Similarity of blood-oxygen-level-dependent (BOLD) fluctuations during rsfMRI between brain regions is thought to reflect intrinsic functional connectivity (FC), potentially due to history of coactivation. To quantify similarity, studies have almost exclusively relied on Pearson correlation, which assumes linearity and can therefore underestimate FC if the hemodynamic response function differs regionally or there is BOLD signal lag between timeseries. Here we show in three cohorts of children, adolescents and adults, with and without autism spectrum disorders (ASDs), that measuring the similarity of BOLD signal fluctuations using non-linear dynamic time warping (DTW) is more robust to global signal regression (GSR), has higher test-retest reliability and is more sensitive to task-related changes in FC. Additionally, when comparing FC between individuals with ASDs and typical controls, more group differences are detected using DTW. DTW estimates are also more related to ASD symptom severity and executive function, while Pearson correlation estimates of FC are more strongly associated with respiration during rsfMRI. Together these findings suggest that non-linear methods such as DTW improve estimation of resting state FC, particularly when studying clinical populations whose hemodynamics or neurovascular coupling may be altered compared to typical controls.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Mapeamento Encefálico/métodos , Encéfalo/fisiopatologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Adolescente , Adulto , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Criança , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Dinâmica não Linear , Adulto Jovem
4.
Mol Psychiatry ; 19(6): 659-67, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23774715

RESUMO

Autism spectrum disorders (ASDs) represent a formidable challenge for psychiatry and neuroscience because of their high prevalence, lifelong nature, complexity and substantial heterogeneity. Facing these obstacles requires large-scale multidisciplinary efforts. Although the field of genetics has pioneered data sharing for these reasons, neuroimaging had not kept pace. In response, we introduce the Autism Brain Imaging Data Exchange (ABIDE)-a grassroots consortium aggregating and openly sharing 1112 existing resting-state functional magnetic resonance imaging (R-fMRI) data sets with corresponding structural MRI and phenotypic information from 539 individuals with ASDs and 573 age-matched typical controls (TCs; 7-64 years) (http://fcon_1000.projects.nitrc.org/indi/abide/). Here, we present this resource and demonstrate its suitability for advancing knowledge of ASD neurobiology based on analyses of 360 male subjects with ASDs and 403 male age-matched TCs. We focused on whole-brain intrinsic functional connectivity and also survey a range of voxel-wise measures of intrinsic functional brain architecture. Whole-brain analyses reconciled seemingly disparate themes of both hypo- and hyperconnectivity in the ASD literature; both were detected, although hypoconnectivity dominated, particularly for corticocortical and interhemispheric functional connectivity. Exploratory analyses using an array of regional metrics of intrinsic brain function converged on common loci of dysfunction in ASDs (mid- and posterior insula and posterior cingulate cortex), and highlighted less commonly explored regions such as the thalamus. The survey of the ABIDE R-fMRI data sets provides unprecedented demonstrations of both replication and novel discovery. By pooling multiple international data sets, ABIDE is expected to accelerate the pace of discovery setting the stage for the next generation of ASD studies.


Assuntos
Mapeamento Encefálico , Encéfalo/patologia , Encéfalo/fisiopatologia , Transtornos Globais do Desenvolvimento Infantil/patologia , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Neuroimagem , Adolescente , Adulto , Criança , Conectoma , Humanos , Disseminação de Informação , Internet , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Fenótipo , Processamento de Sinais Assistido por Computador , Adulto Jovem
5.
J Eur Acad Dermatol Venereol ; 27(12): 1527-34, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23216713

RESUMO

BACKGROUND: Sexually transmitted human papillomavirus (HPV) high-risk types cause carcinoma and low-risk types lead to warts of genitoanal area. Since the HPV vaccine has been introduced, awareness of HPV infection, prevention and health-related behaviour have not been studied in a large sample of young women in Germany. OBJECTIVES: Assessment of awareness and health-related behaviour regarding HPV infection and prevention among young German females. METHODS: In 2010, a postal cross-sectional survey was conducted with a random representative sample size (n = 2000) of females aged 19-35 attending Germany's largest (comprehensive) university, which was designed to obtain data about socio-demographics, the awareness of sexually transmitted HPV, genitoanal neoplasms and their prevention, HPV vaccine, immunisation and cervical cancer screening. RESULTS: Of the 547 (27.3%) participants, 69.1% had heard of HPV, 62.5% were aware of the vaccine, 14.4% were vaccinated and 6.9% reported a history of sexually transmitted infection, including HPV (2.7%). The HPV-related knowledge among those who had heard of it was high (75.1-99.7%), except of that HPV affects men (52.9%) and HPV's causative role in genital (54.2%) and anal (35.6%) warts, and smoking (11.3%) as an HPV risk factor. The lower HPV knowledge score (

Assuntos
Condiloma Acuminado/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Neoplasias do Colo do Útero/prevenção & controle , Adulto , Doenças do Ânus/prevenção & controle , Doenças do Ânus/psicologia , Conscientização , Condiloma Acuminado/psicologia , Feminino , Doenças dos Genitais Femininos/prevenção & controle , Doenças dos Genitais Femininos/psicologia , Alemanha , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18 , Humanos , Infecções por Papillomavirus/psicologia , Doenças Virais Sexualmente Transmissíveis/prevenção & controle , Doenças Virais Sexualmente Transmissíveis/psicologia , Neoplasias do Colo do Útero/psicologia , Adulto Jovem
6.
Neuroimage Rep ; 2(4)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36438080

RESUMO

Neuroimaging studies of autism spectrum disorder (ASD) have been predominantly unimodal. While many fMRI studies have reported atypical activity patterns for diverse tasks, the MEG literature in ASD remains comparatively small. Our group recently reported atypically increased event-related theta power in individuals with ASD during lexicosemantic processing. The current multimodal study examined the relationship between fMRI BOLD signal and anatomically-constrained MEG (aMEG) theta power. Thirty-three adolescents with ASD and 23 typically developing (TD) peers took part in both fMRI and MEG scans, during which they distinguished between standard words (SW), animal words (AW), and pseudowords (PW). Regions-of-interest (ROIs) were derived based on task effects detected in BOLD signal and aMEG theta power. BOLD signal and theta power were extracted for each ROI and word condition. Compared to TD participants, increased theta power in the ASD group was found across several time windows and regions including left fusiform and inferior frontal, as well as right angular and anterior cingulate gyri, whereas BOLD signal was significantly increased in the ASD group only in right anterior cingulate gyrus. No significant correlations were observed between BOLD signal and theta power. Findings suggest that the common interpretation of increases in BOLD signal and theta power as 'activation' require careful differentiation, as these reflect largely distinct aspects of regional brain activity. Some group differences in dynamic neural processing detected with aMEG that are likely relevant for lexical processing may be obscured by the hemodynamic signal source and low temporal resolution of fMRI.

7.
Science ; 196(4289): 489-94, 1977 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-17837065

RESUMO

By considering radioisotope dating as a problem in trace element detection, and by using the cyclotron as a high-energy mass spectrometer for this purpose, we have shown that one can greatly increase the maximum age that can be determined while simultaneously reducing the size of the sample required. The cyclotron can be used to detect atoms or simple molecules that are present at the 10(-16) level or greater. For (14)C dating one should be able to go back 40,000 to 100,000 years with 1- to 100-mg carbon samples; for (10)Be dating, 10 to 30 million years with 1-mm(3) to 10-cm(3) rock samples; for tritium dating, 160 years with a 1-liter water sample. The feasibility of the technique has been demonstrated experimentally by measuring the tritium/deuterium ratio in a sample 24 years old. For samples many half-lives old, the fractional error in the age is small even if rates of production or deposition of the isotopes. Although cyclotrons are expensive to build, their operating costs are relatively low. If several samples are dated per hour the cost per date may not be substantially higher than it is today for decay dating. There are already more than 50 cyclotrons in operation which have the potential to do radioisotope dating, and their application to important problems of dating and trace element analysis should prove very fruitful.

8.
Science ; 288(5474): 2143-4, 2000 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-17758906

RESUMO

According to the Milankovitch theory, changes in the incident solar radiation, called insolation, in the Northern Hemisphere provide the driving force for global glacial cycles. In their Perspective, Karner and Muller discuss recent studies of corals from around the world that shed doubt on the applicability of the theory to the termination of the penultimate glaciation. The authors argue that a fresh, unbiased look at the data is warranted.

9.
Science ; 201(4353): 347-8, 1978 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-17793731

RESUMO

The age of a sample of carbon dioxide has been determined by accelerating the carbon with a cyclotron and detecting the carbon-14 ions in the beam. Nitrogen-14 was eliminated as a background through the use of a range-separation technique. To avoid all possibility of experimenter bias, the measurement was conducted in a blind fashion.

10.
Science ; 196(4289): 521-3, 1977 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-17837081

RESUMO

Quarks of charge +1 and other anomalous hydrogen have been sought by using the 88-inch cyclotron at Berkeley as a high-energy mass spectrometer, with natural hydrogen and deuterium as the sources of ions. No quarks were observed, and limits were placed on their ratio to protons on the earth that vary from < 2 x 10(-19)for high masses (3 to 8.2 atomic mass units) to 10(-13) for the lowest masses (< (1/3) atomic mass unit).

11.
Science ; 200(4341): 489-94, 1978 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-17839416

RESUMO

Atmospherically induced phase perturbations have for years limited the resolution of large optical astronomical telescopes. A prototype telescope system with six movable elements has successfully corrected these phase perturbations. This use of real-time image sharpening has restored stellar images to the diffraction limit (in one dimension) for a 30-centimeter telescope. The double-star image presented indicates that the bulk of the atmospherically induced wave-front phase change occurred within 2 kilometers of the telescope. This implies that, at least for conditions similar to those of our measurement, real-time correction can be accomplished simultaneously for a region at least several arc seconds in angular size. With the present apparatus the technique should be practical for objects as dim as fifth magnitude, and with improvements the technique holds the promise of active image restoration for objects as dim as ninth magnitude.

12.
Water Sci Technol ; 56(3): 145-50, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17802849

RESUMO

Anaerobic ammonia oxidation (Anammox) has been identified as a new general process-strategy for nitrogen removal in wastewater treatment. In order to evaluate the role and effects of the Anammox process in wetlands, laboratory-scale model experiments were performed with planted fixed bed reactors. A reactor (planted with Juncus effusus) was fed with synthetic wastewater containing 150-200 mg L(-1) NH4+ and 75-480 mg L(-1) NO2(-). Under these operating conditions, the plants were affected by the high ammonia and nitrite concentrations and the nitrogen removal rate fell within the same range of 45-49 mg N d(-1) (equivalent to 0.64-0.70 g Nm(-2)d(-1)) as already reported by other authors. In order to stimulate the rate of nitrogen conversion, the planted reactor was inoculated with Anammox biomass. As a result, the rate of nitrogen removal was increased 4-5-fold and the toxic effects on the plants also disappeared. The results show that, in principle, subsurface flow wetlands can also function as an "Anammox bioreactor". However, the design of a complete process for the treatment of waters with a high ammonia load and, in particular, the realisation of simple technical solutions for partial nitrification have still to be developed.


Assuntos
Amônia/metabolismo , Anaerobiose , Biodegradação Ambiental , Nitrogênio/isolamento & purificação , Purificação da Água/métodos , Áreas Alagadas , Biomassa , Reatores Biológicos , Oxirredução , Pesquisa , Eliminação de Resíduos Líquidos/métodos
13.
Plant Dis ; 90(3): 376, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30786569

RESUMO

During late June and early July of 2005, signs of bermudagrass ergot were reported from numerous northern and eastern counties in Oklahoma. Signs were observed primarily on forage-type bermudagrass (Cynodon dactylon (L.) Pers.), as well as bermudagrass turf. During the "honeydew" stage, honeydew was frequently observed exuding from most of the ovaries of infected inflorescences. These signs of ergot have been observed previously on bermudagrass in Oklahoma and Texas (1). Sphacelia-type conidia were abundantly produced during the honeydew stage and were single-celled, hyaline, averaged 14 × 5 µm in size, and were reniform to allantoid in shape. When streaked on water agar, conidia produced terminal holoblastic secondary conidia. Single-spore cultures were isolated from the honeydew of bermudagrasses from Logan and Muskogee counties in Oklahoma and grew slowly as white mycelium on potato dextrose agar (PDA). Koch's postulates were fulfilled for these two isolates by spray inoculating four bermudagrass inflorescences at anthesis with mycelium scraped from a PDA plate and homogenized in water. Control plants' inflorescences were sprayed with a water suspension of a similar amount of sterile PDA as inoculated plants. Plants were placed inside plastic bags to maintain humidity and incubated in a growth chamber at 22°C (14-h photoperiod) and 20°C (10 h of darkness). After 9 days, honeydew exuded from the inoculated inflorescences, but not from the controls. Single-spore cultures were reisolated from the honeydew, and conidia streaked on water agar formed identical secondary conidia. The complete nuclear ribosomal internal transcribed spacer (ITS) region was amplified from DNA extracted from honeydew and single-spore cultures using the ITS4 and ITS5 primers (4) and sequenced. All sequences were identical and a search of GenBank at NCBI found these sequences were most similar to the ITS regions of Claviceps cynodontis Langdon (100%, Accession No. AJ557074) and C. maximensis Theis (99%, Accession No. AJ133396). The ITS sequence from the Logan County isolate was deposited at Gen-Bank (Accession DQ187312). The morphology, secondary conidiation, and ITS sequences identify the causal fungus as C. cynodontis (2) and differentiate it from C. purpurea (Fr.) Tul., the previously identified cause of bermudagrass ergot (1). To our knowledge, this is the first report of C. cynodontis on bermudagrass in Oklahoma and may represent a recent introduction to the United States (2; S. Pazoutová and M. Flieger, personal communication). A Claviceps sp. isolated from bermudagrass has been shown to produce ergot alkaloids possibly causing "bermudagrass tremors" in cattle (3). In regions where bermudagrass is the predominant forage for livestock, the toxicological significance of bermudagrass ergot caused by C. cynodontis is unclear and requires further research. References: (1) K. E. Conway et al. Plant Dis. 76:1077, 1992. (2) S. Pazoutová et al. Can J. Plant Pathol. 27:541, 2005. (3) J. K. Porter et al. J. Agric. Food Chem. 22:838, 1974. (4) T. J. White et al. Pages 315-322 in: PCR Protocols: A Guide to Methods and Applications. Academic Press Inc., New York, 1990.

14.
Water Sci Technol ; 51(9): 205-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16042260

RESUMO

Different types of constructed wetlands in a pilot-plant system were fed with identical municipal waste water to compare the sanitisation process in two-stage systems. With combinations of a vertical and a horizontal flow filter an E. coli reduction of 5 log10 with an E. coli influent concentration of 10(7) MPN/100 ml was achieved. Using different filter materials in each stage the total performance of the two-stage system was independent from the sequence of these materials. However, using coarser filter material in the first stage makes the filter less prone to clogging and is thus the preferential option with regard to operational reliability.


Assuntos
Escherichia coli/isolamento & purificação , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Biodegradação Ambiental , Ecossistema , Filtração , Saneamento , Movimentos da Água
15.
Biol Psychiatry ; 49(8): 665-76, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11313034

RESUMO

BACKGROUND: Early neurodevelopmental pathogenesis in autism potentially affects emerging functional maps, but little imaging evidence is available. METHODS: We studied eight male autistic and eight matched normal subjects, using functional magnetic resonance imaging during visually paced finger movement, compared to a control condition (visual stimulation in the absence of motor response). RESULTS: Groupwise analyses showed activation in contralateral perirolandic cortex, basal ganglia, and thalamus, bilateral supplementary motor area, and ipsilateral cerebellum for both groups. However, activations were less pronounced in the autism group. Direct group comparisons demonstrated greater activation in perirolandic and supplementary motor areas in the control group and greater activation (or reduced deactivation) in posterior and prefrontal cortices in the autism group. Intraindividual analyses further showed that strongest activations were consistently located along the contralateral central sulcus in control subjects but occurred in locations differing from individual to individual in the autism group. CONCLUSIONS: Our findings, though based on a rather small sample, suggest abnormal individual variability of functional maps and less distinct regional activation/deactivation patterns in autism. The observations may relate to known motor impairments in autism and are compatible with the general hypothesis of disturbances of functional differentiation in the autistic cerebrum.


Assuntos
Transtorno Autístico/patologia , Transtorno Autístico/fisiopatologia , Imageamento por Ressonância Magnética , Córtex Motor/patologia , Córtex Motor/fisiopatologia , Adolescente , Adulto , Mapeamento Encefálico , Humanos , Masculino
16.
Arch Neurol ; 55(8): 1113-9, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9708962

RESUMO

OBJECTIVE: There is extensive evidence for post-lesional plasticity in the language and motor domains. We examined possible domain-specific differences in reorganizational patterns, hypothesizing that interhemispheric reorganization would be predominantly homotopic for language, but predominantly nonhomotopic for motor control. DESIGN: Using oxygen 15-water positron emission tomography, regional cerebral blood flow was studied during rest, listening to sentences, repetition of sentences, and finger tapping of the right hand. Task-specific primary, secondary, and tertiary regions of interest were defined according to the degree of regional involvement in language/motor functions as documented in previous studies. Regional activations were compared within and across functional domains. PATIENTS: Nine patients (aged 4-20 years) with unilateral left hemisphere lesion involving both the primary motor and perisylvian language cortices were studied. Two samples of healthy adults were included for additional comparisons. MAIN OUTCOME MEASURE: Hemispheric asymmetry of blood flow changes within regions of interest. RESULTS: As predicted, rightward asymmetry of activations in primary and secondary regions was stronger for language than for movement, but the expected inverse difference for tertiary regions (greater rightward asymmetry of motor activations) was not found. Within-domain comparisons showed that for listening to sentences, rightward asymmetry was strongest in primary and weakest in tertiary regions, whereas the inverse differences were found for movement. CONCLUSION: The findings suggest a greater potential for homotopic interhemispheric reorganization in the language than in the motor domain. Interhemispheric motor reorganization was generally limited.


Assuntos
Encefalopatias/patologia , Encefalopatias/fisiopatologia , Idioma , Desempenho Psicomotor , Tomografia Computadorizada de Emissão , Adolescente , Adulto , Circulação Cerebrovascular , Criança , Diagnóstico Diferencial , Feminino , Humanos , Masculino
17.
Neurology ; 52(5): 1057-9, 1999 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-10102428

RESUMO

The brain weights of 21 postmortem autism cases (5 new and 16 previously published) were compared with normal brain weights from six autopsy studies. Of the 21 cases, 17 had normal brain weights and 1 was micrencephalic. Compared with the normal median (1,460 g), three autism cases were megalencephalic: two (1,810 g and 1,820 g) had been previously reported and one (1,880 g) was a new case. Brain weight is thus normal in most postmortem cases of autism. There are, however, rare cases of megalencephaly and possibly micrencephaly.


Assuntos
Transtorno Autístico/patologia , Encéfalo/patologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Tamanho do Órgão
18.
Neuropsychologia ; 37(5): 545-57, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10340314

RESUMO

Functional neuroimaging studies have shown enhanced right-hemisphere language activations in adults with left-hemisphere damage. We hypothesized that this effect would be stronger in patients with lesion occurring early in development. Using [15O]-water PET, we studied eight normal adults and 23 patients with unilateral left lesion during rest, listening to sentences, and sentence repetition. Thirteen patients had lesions with early onset (< 5 years) and ten had lesions with late onset (> 20 years). For listening to sentences, frontotemporal blood flow increases were significantly stronger in the left than in the right hemisphere in normal adults. This normal asymmetry was reduced in patients with late lesion and reversed in those with early lesion. For sentence repetition, analogous group differences were significant for the basal ganglia, but failed to reach significance for the (pre)motor and insular regions. We conclude that left lesion leads to alterations in the asymmetry of language activations (in and beyond the perisylvian areas). In addition, rightward shifts of language activation tend to be stronger as a consequence of early (as compared to late) lesion. Finally, postlesional reorganization appears to reflect a coexistence of 'additive' and 'subtractive' effects, i.e., activation in some regions that are not normally involved in language processing and lack of activation in other (undamaged) regions that are normally activated by language tasks.


Assuntos
Encéfalo/irrigação sanguínea , Lateralidade Funcional , Idioma , Tomografia Computadorizada de Emissão , Adolescente , Adulto , Idade de Início , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Dano Encefálico Crônico/patologia , Dano Encefálico Crônico/psicologia , Criança , Feminino , Lobo Frontal/irrigação sanguínea , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Lobo Temporal/irrigação sanguínea , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/patologia
19.
Biotechnol Adv ; 22(1-2): 93-117, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14623046

RESUMO

Constructed wetlands are a natural alternative to technical methods of wastewater treatment. However, our understanding of the complex processes caused by the plants, microorganisms, soil matrix and substances in the wastewater, and how they all interact with each other, is still rather incomplete. In this article, a closer look will be taken at the mechanisms of both plants in constructed wetlands and the microorganisms in the root zone which come into play when they remove contaminants from wastewater. The supply of oxygen plays a crucial role in the activity and type of metabolism performed by microorganisms in the root zone. Plants' involvement in the input of oxygen into the root zone, in the uptake of nutrients and in the direct degradation of pollutants as well as the role of microorganisms are all examined in more detail. The ways in which these processes act to treat wastewater are dealt with in the following order: Technological aspects; The effect of root growth on the soil matrix; Gas transport in helophytes and the release of oxygen into the rhizosphere; The uptake of inorganic compounds by plants; The uptake of organic pollutants by plants and their metabolism; The release of carbon compounds by plants; Factors affecting the elimination of pathogenic germs.


Assuntos
Ecossistema , Plantas/metabolismo , Plantas/microbiologia , Microbiologia da Água , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos , Biodegradação Ambiental , Resíduos Industriais/prevenção & controle , Oxigênio/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Microbiologia do Solo
20.
Neuroreport ; 8(17): 3767-70, 1997 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9427367

RESUMO

Most language mapping studies have focussed on activations for single-word tasks. We examined activations for verbal auditory and generation tasks using sentence stimuli. [15O]-water PET was performed in 4 female and 5 male normal adults. Listening to sentences (minus rest) activated the superior and middle temporal gyri bilaterally, but mean activation was significantly stronger on the left. The strongest activation for sentence generation (minus repetition) was seen in the left middle and inferior frontal gyri (area 46). This focus appears to be anterior to activations reported for single-word generation, possibly due to greater verbal working memory demands of the sentential task. Additional activation of the left inferior temporal lobe can be attributed to lexicosemantic processing.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Idioma , Fala , Estimulação Acústica , Adulto , Percepção Auditiva , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/diagnóstico por imagem , Circulação Cerebrovascular , Feminino , Lobo Frontal/fisiologia , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória , Lobo Parietal/fisiologia , Radiografia , Tempo de Reação , Lobo Temporal/fisiologia , Tomografia Computadorizada de Emissão/métodos
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