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1.
Sci Rep ; 14(1): 1898, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253660

RESUMO

Escalating environmental threats to coral reefs coincides with global advancements in coral restoration programs. To improve long-term efficacy, practitioners must consider incorporating genotypes resilient to ocean warming and disease while maintaining genetic diversity. Identifying such genotypes typically occurs under long-term exposures that mimic natural stressors, but these experiments can be time-consuming, costly, and introduce tank effects, hindering scalability for hundreds of nursery genotypes used for outplanting. Here, we evaluated the efficacy of the acute Coral Bleaching Automated Stress System (CBASS) against long-term exposures on the bleaching response of Acropora cervicornis, the dominant restoration species in Florida's Coral Reef. Comparing bleaching metrics, Fv/Fm, chlorophyll, and host protein, we observed similar responses between the long-term heat and the CBASS treatment of 34.3 °C, which was also the calculated bleaching threshold. This suggests the potential of CBASS as a rapid screening tool, with 90% of restoration genotypes exhibiting similar bleaching tolerances. However, variations in acute bleaching phenotypes arose from measurement timing and experiment heat accumulation, cautioning against generalizations solely based on metrics like Fv/Fm. These findings identify the need to better refine the tools necessary to quickly and effectively screen coral restoration genotypes and determine their relative tolerance for restoration interventions.


Assuntos
Antozoários , Animais , Antozoários/genética , Recifes de Corais , Benchmarking , Bioensaio , Clorofila
2.
Microbiol Resour Announc ; 11(2): e0119921, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35175123

RESUMO

Stony coral tissue loss disease (SCTLD) is decimating Caribbean corals. Here, through the metatranscriptomic assembly and annotation of two alphaflexivirus-like strains, we provide genomic evidence of filamentous viruses in SCTLD-affected, -exposed, and -unexposed coral colonies. These data will assist in clarifying the roles of viruses in SCTLD.

3.
Ecology ; 95(7): 1981-94, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25163129

RESUMO

The putative increase in coral diseases in the Caribbean has led to extensive declines in coral populations. Coral diseases are a consequence of the complex interactions among the coral hosts, the pathogens, and the environment. Yet, the relative influence that each of these components has on the prevalence of coral diseases is unclear. Also unknown is the extent to which historical thermal-stress events have influenced the prevalence of contemporary coral diseases and the potential adjustment of coral populations to thermal stress. We used a Bayesian approach to test the hypothesis that in 2012 the relative risk of four signs of coral disease (white signs, dark spots, black bands, and yellow signs) differed at reef locations with different thermal histories. We undertook an extensive spatial study of coral diseases at four locations in the Caribbean region (10(3) km), two with and two without a history of frequent thermal anomalies (approximately 4-6 years) over the last 143 years (1870-2012). Locations that historically experienced frequent thermal anomalies had a significantly higher risk of corals displaying white signs, and had a lower risk of corals displaying dark spots, than locations that did not historically experience frequent thermal anomalies. By contrast, there was no relationship between the history of thermal stress and the relative risk of corals displaying black bands and yellow signs, at least at the spatial scale of our observations.


Assuntos
Antozoários/fisiologia , Recifes de Corais , Temperatura Alta , Estresse Fisiológico , Animais , Região do Caribe , Monitoramento Ambiental , Fatores de Tempo
4.
Indian J Nephrol ; 22(2): 86-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22787307

RESUMO

Deceased donor kidney transplantation have been in place for more than ten years at Groote Schuur Hospital in Cape Town, South Africa. This retrospective review between 1995 and 2005 reports the experience with 824 deceased donor referrals. Race breakdown showed that 321 donors were black, 154 white, 318 mixed race and 30 unrecorded. Consent remains a major problem in South Africa and we were unable to obtain consent in 43% of our patients. Only 20% of donors had natural causes of death - the majority died because of trauma/unnatural circumstances. For this reason the average age of our donors are 26 years. A and O blood group donors were the most prevalent with A blood group patients making up 38% and O blood group 39% of the donor population.

5.
Int J Psychophysiol ; 83(1): 87-95, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22079828

RESUMO

We investigated EEG-power and EEG-coherence changes in a unimodal and a crossmodal matching-to-sample working memory task with either visual or kinesthetic stimuli. Angle-shaped trajectories were used as stimuli presented either as a moving dot on a screen or as a passive movement of a haptic device. Effects were evaluated during the different phases of encoding, maintenance, and recognition. Alpha power was modulated during encoding by the stimulus modality, and in crossmodal conditions during encoding and maintenance by the expected modality of the upcoming test stimulus. These power modulations were observed over modality-specific cortex regions. Systematic changes of coherence for crossmodal compared to unimodal tasks were not observed during encoding and maintenance but only during recognition. There, coherence in the theta-band increased between electrode sites over left central and occipital cortex areas in the crossmodal compared to the unimodal conditions. The results underline the importance of modality-specific representations and processes in unimodal and crossmodal working memory tasks. Crossmodal recognition of visually and kinesthetically presented object features seems to be related to a direct interaction of somatosensory/motor and visual cortex regions by means of long-range synchronization in the theta-band and such interactions seem to take place at the beginning of the recognition phase, i.e. when crossmodal transfer is actually necessary.


Assuntos
Ondas Encefálicas/fisiologia , Córtex Cerebral/fisiologia , Cinestesia , Memória de Curto Prazo/fisiologia , Movimento , Adulto , Ritmo alfa/fisiologia , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Estimulação Física , Tempo de Reação , Ritmo Teta , Fatores de Tempo , Adulto Jovem
6.
Phys Rev Lett ; 106(13): 137602, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21517420

RESUMO

Electron emission from the negative electron affinity (NEA) surface of hydrogen terminated, boron doped diamond in the [100] orientation is investigated using angle resolved photoemission spectroscopy (ARPES). ARPES measurements using 16 eV synchrotron and 6 eV laser light are compared and found to show a catastrophic failure of the sudden approximation. While the high energy photoemission is found to yield little information regarding the NEA, low energy laser ARPES reveals for the first time that the NEA results from a novel Franck-Condon mechanism coupling electrons in the conduction band to the vacuum. The result opens the door to the development of a new class of NEA electron emitter based on this effect.

7.
Dis Aquat Organ ; 90(2): 85-92, 2010 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-20662364

RESUMO

Scleractinian corals (phylum Cnidaria, class Anthozoa) have innate immunological responses against infections. Research has recently suggested that corals also possess an adaptive-like immunological repertoire that recognizes specific pathogens and allografts. While evolutionarily distinct, the corals' innate and adaptive-like immunity systems are not mutually exclusive because the phagocytic cells of the non-specific, innate immune system may activate specific adaptive immunological responses. Warming oceans may immunocompromise coral hosts, making them more susceptible to tropical marine diseases, independent of the virulence of the pathogen. The ability of corals to ward off both primary and opportunistic infections, through adaptive-like mechanisms, may play a critical role in the corals' ability to fight future disease infection. Here we show evidence that corals possess immunological repertoires that extend well beyond simple innate defenses. The extent to which corals have developed such an adaptive-like immune repertoire will determine whether corals will survive climate change and other anthropogenic disturbances.


Assuntos
Antozoários/imunologia , Antozoários/microbiologia , Imunidade Adaptativa , Animais , Antozoários/anatomia & histologia , Catecol Oxidase/metabolismo , Precursores Enzimáticos/metabolismo , Regulação da Expressão Gênica/imunologia , Fagócitos , Proteínas/imunologia , Proteínas/metabolismo
8.
Biol Bull ; 210(2): 132-9, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16641518

RESUMO

In euryhaline crabs, ion-transporting cells are clustered into osmoregulatory patches on the lamellae of the posterior gills. To examine changes in the branchial osmoregulatory patch in the blue crab Callinectes sapidus in response to change in salinity and to correlate these changes with other osmoregulatory responses, crabs were acclimated to a range of salinities between 10 and 35 ppt. When crabs that had been acclimated to 35 ppt were subsequently transferred to 10 ppt, both the size of the osmoregulatory patch on individual gill lamellae and the specific activity of Na+, K+-ATPase in whole-gill homogenates increased only after the first 24 h of exposure to dilute seawater. Enzyme activity and size of patch area increased gradually and reached their maxima (increasing by 200% and 60%, respectively) 6 days following transfer to 10 ppt seawater and then remained at these levels. Patch size at acclimation varied inversely with the salinity for seawater dilutions below 26 ppt (the isosmotic point of the crab), although it did not vary in salinities at or above 26 ppt. Thus, the size of the patch clearly is modulated with acclimation salinity, but it increases only in those salinities in which the crab hyperosmoregulates. An increase in the total RNA/DNA ratio in gill homogenates, the lack of mitotic figures in the lamellae, and the lack of incorporation of bromodeoxyuridine into nuclei of lamellar epithelial cells during acclimation to dilute seawater were interpreted as evidence that no cell proliferation had occurred and that increases in the size of the osmoregulatory patch occurred through differentiation of existing gas exchange cells or of undifferentiated epithelial cells into ion-transporting cells.


Assuntos
Braquiúros/metabolismo , Epitélio/efeitos dos fármacos , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Cloreto de Sódio/farmacologia , Equilíbrio Hidroeletrolítico/fisiologia , Adaptação Fisiológica , Animais , Braquiúros/anatomia & histologia , Epitélio/anatomia & histologia , Epitélio/metabolismo , Brânquias/anatomia & histologia , Masculino , Água do Mar , Fatores de Tempo
9.
Adv Mater ; 17(11): 1410-1414, 2005 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34412424

RESUMO

Charge traps in pentacene thin-film transistors (Figure, left) have been imaged using electric force microscopy. The Figure shows a map of the trap distribution just below (middle) and well above (right) the transistor threshold voltage. It is found that the long-lived charge traps in polycrystalline pentacene are distributed inhomogeneously and do not appear to be associated with grain boundaries, as is generally assumed.

10.
Sportverletz Sportschaden ; 17(4): 171-5, 2003 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-14666433

RESUMO

UNLABELLED: In a prospective study we investigated the value regarding muscle strength of two stairclimbers with either coupled or non-coupled pedals at either high or low stepping frequency. Following autologous patellar tendon graft surgery 14 patients for each group completed a strict exercising program. After 6 weeks of training a clear advantage was found for the group stepping at low speed with coupled pedals when measuring: At 60 degree/s the average maximum torque of extension increased from 37.7 to 61.7% as compared to a control group (30 to 47.2%). Analogous the percent ratio of flexion/extension (H/Q ratio) improved significantly. During the second training period the improvement of the extension strength as well as the H/Q ratio was found to be only marginal. No negative effects of this type of training on ligament stability could be detected. CONCLUSIONS: Regarding a faster recovery of muscle strength and the improvement of the intermuscular coordination, the stairclimber training, beginning with week 7 after surgery and lasting over a period of 6 weeks, is considered advantageous, especially when exercising is done at low speed and with coupled pedals.


Assuntos
Lesões do Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/cirurgia , Terapia por Exercício/métodos , Instabilidade Articular/reabilitação , Instabilidade Articular/cirurgia , Traumatismos do Joelho/reabilitação , Músculo Esquelético/fisiopatologia , Modalidades de Fisioterapia/métodos , Adolescente , Adulto , Feminino , Humanos , Traumatismos do Joelho/cirurgia , Masculino , Resultado do Tratamento
11.
Genetics ; 159(4): 1527-38, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11779794

RESUMO

The budding yeast Saccharomyces cerevisiae generates calcium signals during the response to mating pheromones that promote survival of unmated cells. A Ca(2+) channel composed of Cch1p and Mid1p was previously shown to be necessary for the production of these calcium signals. However, we find that the Cch1p-Mid1p high-affinity Ca(2+) influx system (HACS) contributes very little to signaling or survival after treatment with alpha-factor in rich media. HACS activity was much greater after calcineurin inactivation or inhibition, suggesting the Cch1p-Mid1p Ca(2+) channel is subject to direct or indirect regulation by calcineurin. Instead a distinct low-affinity Ca(2+) influx system (LACS) was stimulated by pheromone signaling in rich medium. LACS activity was insensitive to calcineurin activity, independent of Cch1p and Mid1p, and sufficient to elevate cytosolic free Ca(2+) concentrations ([Ca(2+)]c) in spite of its 16-fold lower affinity for Ca(2+). Overexpression of Ste12p or constitutive activation of this transcription factor in dig1 dig2 double mutants had no effect on LACS activity but stimulated HACS activity when calcineurin was also inactivated. Ste12p activation had no effect on Cch1p or Mid1p abundance, suggesting the involvement of another target of Ste12p in HACS stimulation. LACS activation required treatment with mating pheromone even in dig1 dig2 double mutants and also required FAR1, SPA2, and BNI1, which are necessary for proper cell cycle arrest and polarized morphogenesis. These results show that distinct branches of the pheromone-signaling pathway independently regulate HACS and LACS activities, either of which can promote survival during long-term responses.


Assuntos
Cálcio/metabolismo , Regulação Fúngica da Expressão Gênica , Feromônios/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Transdução de Sinais , Equorina/metabolismo , Transporte Biológico , Western Blotting , Calcineurina/metabolismo , Cálcio/farmacologia , Canais de Cálcio/genética , Canais de Cálcio/fisiologia , Ciclo Celular , Relação Dose-Resposta a Droga , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/fisiologia , Cinética , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/fisiologia , Azul de Metileno/farmacologia , Mutação , Plasmídeos/metabolismo , Fatores de Tempo , Fatores de Transcrição/metabolismo , beta-Galactosidase/metabolismo
12.
J Psycholinguist Res ; 21(1): 41-57, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1548620

RESUMO

Vocal loudness productions of five similar groups of speakers were analyzed. The groups differed significantly in "comfortable" loudness, in multiples (2x, 4x, and 0.5x) of comfortable loudness, and in ranges (4x -0.5x) of comfortable loudness. Interclass reliabilities for sets of measures were high and highly significant. Implications for the specification of vocal loudness behaviors are discussed.


Assuntos
Percepção Sonora , Comportamento Verbal , Qualidade da Voz , Adulto , Feminino , Humanos , Masculino , Psicolinguística , Espectrografia do Som
13.
Artigo em Alemão | MEDLINE | ID: mdl-1932447

RESUMO

We examined the perioperative course of 1013 patients who had undergone coronary surgery between 1984 and 1987, to identify preoperative examination findings which are suitable as risk indicators in coronary surgery. The features we paid attention to were: anamnestic data, parameters of coronary disease, haemodynamic parameters and accompanying illnesses. We considered a perioperative course as complicated when systolic blood pressure dropped to 80 mmHg or less for longer than 15 min, when reconnection to the heart-lung-machine was necessary, when an intra-aortal balloon counterpulsation was required, when the patient had to have mechanical ventilation for longer than 24 h, when resuscitation took place, or when the patient died in the hospital. The Chi-square test was used for statistical analysis. Very good risk indicators (p less than 0.001) were: age greater than 60 y, resuscitation history, more than two bypass grafts, SvO2 70%, ejection fraction less than 50% and cardiac index less than 2.5 l/min*m2. Good risk indicators (p less than 0.001) were: functional capacity less than 50 watts, more than one previous myocardial infarction and LVEDP greater than 20 mmHg. LCA-stenosis, arterial hypertension with diastolic blood pressure values above 100 mmHg, and obstructive airway disease were identified as suitable risk indicators (p less than 0.05). The following findings were combined with significantly increased mortality: female sex, age over 60 years, two or more previous myocardial infarctions, history of resuscitation, mixed venous oxygen saturation below 70% and the need for three or more bypass grafts for complete revascularisation.


Assuntos
Ponte de Artéria Coronária/mortalidade , Adulto , Fatores Etários , Idoso , Ponte de Artéria Coronária/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Oxigênio/sangue , Ressuscitação , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
14.
J Speech Hear Res ; 34(2): 252-9, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2046349

RESUMO

The variable nature of the perioral system as a force generator is due, in large part, to differences in the spatial arrangement and degree of muscle representation in this region. This fact requires careful consideration when attempting to compare select properties of force dynamics among individual subjects in health and disease. The objective of the present study was to determine the relation between an indirect measure of muscle length (interangle span) and in vivo resultant force in the perioral region of normal adult subjects. Perioral force associated with the maximum voluntary contraction (MVC) was found to increase systematically with increases in the span between the load sensitive cantilevers positioned between the corners of the mouth. The active force component of the MVC was significantly greater for male than female subjects, whereas passive forces were equal. Active force is discussed in relation to rest positions of the oral opening and the assessment of the force operating range for speech and other oromotor behaviors in health and disease.


Assuntos
Músculos Faciais/fisiologia , Lábio/fisiologia , Adulto , Eletromiografia , Músculos Faciais/anatomia & histologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia
16.
Arch Kriminol ; 173(1-2): 29-35, 1984.
Artigo em Alemão | MEDLINE | ID: mdl-6712415

RESUMO

From 1.4. -30.10.1982 all heroin samples weighing more than 5 g seized in the States of Baden-Württemberg, Hesse and by the Bundeskriminalamt were analyzed by capillary gas chromatography during a pilot project. For comparison of samples ratios of concentrations of heroin (including its decomposition products 0(6)-acetylmorphine and morphine) and its natural by-products of synthesis acetylcodeine, papaverine, and narcotine (noscapine) were determined. The application of these parameters and further qualitative and quantitative criteria for heroin comparison for investigative and legal purposes are discussed.


Assuntos
Cromatografia/métodos , Medicina Legal , Heroína/análise , Alemanha Ocidental , Humanos , Morfina/análise , Derivados da Morfina/análise , Noscapina/análise , Papaverina/análise , Projetos Piloto
17.
Z Orthop Ihre Grenzgeb ; 120(1): 29-33, 1982 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-7080623

RESUMO

Difficult fractures of the calcaneus are therapeutic problem today. From 1965 to 1977 147 patients were non-operative treated in the department of general surgery - including cases from department of orthopedic surgery. 67 patients with fractures of the os calcis were controlled between 3 and 15 years after accident. The various methods of conservative treatment are discussed. The early functional treatment had the better late results than other conservative methods i.e.: fewer pain and better flexibility of the talo-calcaneo-navicular and talo-calcanean joint, sooner taking up of the former occupation and lower decrease in performance.


Assuntos
Calcâneo/lesões , Fraturas Ósseas/terapia , Seguimentos , Fixação de Fratura , Humanos , Imobilização
20.
J Acoust Soc Am ; 65(2): 481-6, 1979 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-385662

RESUMO

This paper describes the design refinements made in an earlier prototype system for transducing lip and jaw movements in the midsagittal plane. Major improvements over the prototype system included: reduced transducer loading, improved two-dimensional separation and resolution, elimination of possible artifacts due to lateral-medial or rotational movement, electrical isolation of the subject from the transducer, increased capability to transduce movements of children as well as adults, and an accessory instrument for orienting the transducers with reference to defined anatomical planes.


Assuntos
Arcada Osseodentária/fisiologia , Lábio/fisiologia , Movimento , Patologia da Fala e Linguagem/instrumentação , Fala/fisiologia , Humanos
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