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1.
Sci Rep ; 12(1): 1945, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35121776

RESUMO

Java vulnerabilities correspond to 91% of all exploits observed on the worldwide web. The present work aims to create antivirus software with machine learning and artificial intelligence and master in Java malware detection. Within the proposed methodology, the suspected JAR sample is executed to intentionally infect the Windows OS monitored in a controlled environment. In all, our antivirus monitors and considers, statistically, 6824 actions that the suspected JAR file can perform when executed. Our antivirus achieved an average performance of 91.58% in the distinction between benign and malware JAR files. Different initial conditions, learning functions and architectures of our antivirus are investigated. The limitations of commercial antiviruses can be supplied by intelligent antiviruses. Instead of blacklist-based models, our antivirus allows JAR malware detection preventively and not reactively as Oracle's Java and traditional antivirus modus operandi.

2.
Pharmacol Rep ; 73(3): 954-961, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33523405

RESUMO

BACKGROUND: Chikungunya fever is an endemic disease caused by the Chikungunya virus (CHIKV) to which there is no vaccine or effective antiviral drug treatment so far. Our study aimed to evaluate the potential anti-CHIKV activity of memantine hydrochloride (mtnH), a drug from the class of the aminoadamantanes approved for the treatment of Alzheimer´s disease, as a possible drug to be repurposed to the treatment of Chikungunya fever. METHODS: MtnH antiviral activity against CHIKV was determined by infecting BHK-21 cells with CHIKV-nanoluc, a virus carrying the marker nanoluciferase reporter, in the presence or absence of mtnH at concentrations ranging from 500 to 1.45 µM. The effective concentration of 50% inhibition (EC50) was calculated. Cell viability assay (determination of CC50) was also performed employing BHK-21 cells. Mutagenic assays were performed by the Salmonella Typhimurium/microsome assay (Ames test). RESULTS: MtnH presented a CC50 of 248.4 ± 31.9 µM and an EC50 of 32.4 ± 4 µM against CHIKV in vitro. The calculated selectivity index (SI) was 7.67. MtnH did not induce genetic mutation in Salmonella strains with or without an external metabolizing system. CONCLUSION: With the data herein presented, it is possible to hypothesize mtnH as a viable candidate to be repurposed as an anti-CHIKV drug. Clinical assays are, therefore, encouraged due to the promising in vitro results. The drug memantine hydrochloride is herein personified with a doubt: as a prior regulated drug against Alzheimer, could it follow the path against Chikungunya virus too?


Assuntos
Antivirais/farmacologia , Febre de Chikungunya/tratamento farmacológico , Vírus Chikungunya/efeitos dos fármacos , Memantina/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Febre de Chikungunya/virologia , Humanos
3.
J Theor Biol ; 459: 154-161, 2018 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-30296449

RESUMO

Living elephants produce seismic waves during vocalizations and locomotion that are potentially detectable at large distances. In the Mesozoic world, seismic waves were probably a very relevant source of information about the behavior of large dinosaurs. In this work, we study the relationship between foot shape and the directivity pattern of seismic waves generated during locomotion. For enlarged foot morphologies (based on a morphological index) of theropod dinosaurs, there is a marked effect of seismic wave directivity at 20 m. This effect is not important in the foot morphologies of other dinosaurs, including the foot shapes of herbivores and theropods such as therizinosaurids. This directivity produces a lower intensity in the forward direction that would slightly reduce the probability of detection of an ambush predator. Even more relevant is the fact that during the approach of a predator, the intensity of seismic waves detected by potential prey remains constant in the mentioned distance range. This effect hides the predator's approach, and we call this "seismic wave camouflage". We also discuss the potential relationship of this effect with enlarged fossil footprints assigned to metatarsal support.


Assuntos
Dinossauros/fisiologia , Pé/anatomia & histologia , Locomoção , Localização de Som , Animais , Dinossauros/anatomia & histologia , Fósseis , Comportamento Predatório , Som
4.
J Fish Biol ; 91(5): 1392-1406, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28944458

RESUMO

Between February 2015 and 2016, samples of the Indo-Pacific goldspotted spinefoot Siganus punctatus were taken from local fish markets, feeding sites and nursery grounds on the main island of Pohnpei, Micronesia, to ascertain sexual pattern, reproductive seasonality, age, growth and mortality. Microscopic examinations of gonads identified two seasonal peaks in reproduction: February to May and September to December, with evidence of some spawning activity in most months. Ripe females were observed 4 days on either side of the new moon. Females first matured at c. 180 mm fork length (LF ) and 1 year of age, which coincides with their entry into the fishery. Ninety five per cent of individuals were less than 3 years and the oldest fish were 8 years. To examine the species vulnerability to fishing, a tag-and-recapture study was conducted over 4 months in 2015 in a locally managed marine area and at an unprotected site. Findings suggest high residency and high vulnerability to fishing at shallow-water feeding sites and restricted migration overall. The placement of marine protected areas within critical habitat appears to be an effective conservation strategy for this species, particularly when combined with gear and seasonal market restrictions during vulnerable life-history phases.


Assuntos
Pesqueiros , Peixes/fisiologia , Reprodução , Animais , Ecossistema , Feminino , Peixes/crescimento & desenvolvimento , Gônadas/crescimento & desenvolvimento , Gônadas/fisiologia , Masculino , Micronésia , Estações do Ano , Maturidade Sexual
6.
Proc Biol Sci ; 276(1675): 3971-8, 2009 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-19710060

RESUMO

The importance of the centre of percussion (CP) of some hand-held sporting equipment (such as tennis rackets and baseball bats) for athletic performance is well known. In order to avoid injuries it is important that powerful blows are located close to the CP. Several species of glyptodont (giant armoured mammals) had tail clubs that can be modelled as rigid beams (like baseball bats) and it is generally assumed that these were useful for agonistic behaviour. However, the variation in tail club morphology among known genera suggests that a biomechanical and functional analysis of these structures could be useful. Here, we outline a novel method to determine the CP of the glyptodont tail clubs. We find that the largest species had the CP very close to the possible location of horny spikes. This is consistent with the inference that they were adapted to delivering powerful blows at that point. Our new analysis reinforces the case for agonistic use of tail clubs in several glyptodont species.


Assuntos
Fenômenos Biomecânicos/fisiologia , Fósseis , Mamíferos/anatomia & histologia , Mamíferos/fisiologia , Cauda/anatomia & histologia , Animais , Cauda/fisiologia
7.
Proc Natl Acad Sci U S A ; 104(39): 15248-53, 2007 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-17881573

RESUMO

Data from the satellite-based Special Sensor Microwave Imager (SSM/I) show that the total atmospheric moisture content over oceans has increased by 0.41 kg/m(2) per decade since 1988. Results from current climate models indicate that water vapor increases of this magnitude cannot be explained by climate noise alone. In a formal detection and attribution analysis using the pooled results from 22 different climate models, the simulated "fingerprint" pattern of anthropogenically caused changes in water vapor is identifiable with high statistical confidence in the SSM/I data. Experiments in which forcing factors are varied individually suggest that this fingerprint "match" is primarily due to human-caused increases in greenhouse gases and not to solar forcing or recovery from the eruption of Mount Pinatubo. Our findings provide preliminary evidence of an emerging anthropogenic signal in the moisture content of earth's atmosphere.


Assuntos
Atmosfera , Clima , Efeito Estufa , Movimentos do Ar , Simulação por Computador , Planeta Terra , Ecologia , Atividades Humanas , Humanos , Umidade , Micro-Ondas , Luz Solar , Fatores de Tempo , Água/química
8.
Proc Natl Acad Sci U S A ; 103(38): 13905-10, 2006 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-16968781

RESUMO

Previous research has identified links between changes in sea surface temperature (SST) and hurricane intensity. We use climate models to study the possible causes of SST changes in Atlantic and Pacific tropical cyclogenesis regions. The observed SST increases in these regions range from 0.32 degrees C to 0.67 degrees C over the 20th century. The 22 climate models examined here suggest that century-timescale SST changes of this magnitude cannot be explained solely by unforced variability of the climate system. We employ model simulations of natural internal variability to make probabilistic estimates of the contribution of external forcing to observed SST changes. For the period 1906-2005, we find an 84% chance that external forcing explains at least 67% of observed SST increases in the two tropical cyclogenesis regions. Model "20th-century" simulations, with external forcing by combined anthropogenic and natural factors, are generally capable of replicating observed SST increases. In experiments in which forcing factors are varied individually rather than jointly, human-caused changes in greenhouse gases are the main driver of the 20th-century SST increases in both tropical cyclogenesis regions.


Assuntos
Desastres , Água do Mar , Temperatura , Clima Tropical , Oceano Atlântico , Simulação por Computador , Efeito Estufa , Humanos , Modelos Teóricos , Oceano Pacífico , Fatores de Tempo
9.
Proc Biol Sci ; 272(1574): 1769-73, 2005 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16096087

RESUMO

'Terror bird' is a common name for the family Phorusrhacidae. These large terrestrial birds were probably the dominant carnivores on the South American continent from the Middle Palaeocene to the Pliocene-Pleistocene limit. Here we use a mechanical model based on tibiotarsal strength to estimate maximum running speeds of three species of terror birds: Mesembriornis milneedwardsi, Patagornis marshi and a specimen of Phorusrhacinae gen. The model is proved on three living large terrestrial bird species. On the basis of the tibiotarsal strength we propose that Mesembriornis could have used its legs to break long bones and access their marrow.


Assuntos
Aves/fisiologia , Fósseis , Locomoção/fisiologia , Modelos Teóricos , Animais , Fenômenos Biomecânicos , Aves/anatomia & histologia , Membro Posterior/anatomia & histologia , Membro Posterior/fisiologia
10.
Proc Natl Acad Sci U S A ; 102(15): 5326-33, 2005 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-15749818

RESUMO

South Asian emissions of fossil fuel SO(2) and black carbon increased approximately 6-fold since 1930, resulting in large atmospheric concentrations of black carbon and other aerosols. This period also witnessed strong negative trends of surface solar radiation, surface evaporation, and summer monsoon rainfall. These changes over India were accompanied by an increase in atmospheric stability and a decrease in sea surface temperature gradients in the Northern Indian Ocean. We conducted an ensemble of coupled ocean-atmosphere simulations from 1930 to 2000 to understand the role of atmospheric brown clouds in the observed trends. The simulations adopt the aerosol radiative forcing from the Indian Ocean experiment observations and also account for global increases in greenhouse gases and sulfate aerosols. The simulated decreases in surface solar radiation, changes in surface and atmospheric temperatures over land and sea, and decreases in monsoon rainfall are similar to the observed trends. We also show that greenhouse gases and sulfates, by themselves, do not account for the magnitude or even the sign in many instances, of the observed trends. Thus, our simulations suggest that absorbing aerosols in atmospheric brown clouds may have played a major role in the observed regional climate and hydrological cycle changes and have masked as much as 50% of the surface warming due to the global increase in greenhouse gases. The simulations also raise the possibility that, if current trends in emissions continue, the subcontinent may experience a doubling of the drought frequency in the coming decades.

11.
Science ; 301(5632): 479-83, 2003 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-12881562

RESUMO

Observations indicate that the height of the tropopause-the boundary between the stratosphere and troposphere-has increased by several hundred meters since 1979. Comparable increases are evident in climate model experiments. The latter show that human-induced changes in ozone and well-mixed greenhouse gases account for approximately 80% of the simulated rise in tropopause height over 1979-1999. Their primary contributions are through cooling of the stratosphere (caused by ozone) and warming of the troposphere (caused by well-mixed greenhouse gases). A model-predicted fingerprint of tropopause height changes is statistically detectable in two different observational ("reanalysis") data sets. This positive detection result allows us to attribute overall tropopause height changes to a combination of anthropogenic and natural external forcings, with the anthropogenic component predominating.

12.
Science ; 300(5623): 1280-4, 2003 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-12730497

RESUMO

Two independent analyses of the same satellite-based radiative emissions data yield tropospheric temperature trends that differ by 0.1 degrees C per decade over 1979 to 2001. The troposphere warms appreciably in one satellite data set, while the other data set shows little overall change. These satellite data uncertainties are important in studies seeking to identify human effects on climate. A model-predicted "fingerprint" of combined anthropogenic and natural effects is statistically detectable only in the satellite data set with a warming troposphere. Our findings show that claimed inconsistencies between model predictions and satellite tropospheric temperature data (and between the latter and surface data) may be an artifact of data uncertainties.

13.
Ultrasound Obstet Gynecol ; 20(5): 464-7, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12423483

RESUMO

OBJECTIVES: The purpose of this investigation was to determine the preferable method, either measuring to the umbilical cord or through the umbilical cord to the base of the pocket, of ultrasonically estimating amniotic fluid volume. SUBJECT AND METHODS: This was a prospective study carried out in singleton pregnancies undergoing a third-trimester amniocentesis. The amniotic fluid index (AFI) and single deepest pocket (SDP) were measured prior to amniocentesis. If measured spaces contained umbilical cord, measurements were made to and through the cord. Actual amniotic fluid volume was determined by the dye-dilution technique. RESULTS: One-hundred pregnancies were evaluated. Low dye-determined volume was identified in a significantly greater number of pregnancies using the AFI to the cord (7/28, 25%) compared to through the cord (2/28, 7%) (P = 0.025). The SDP technique to the cord was superior in low volumes (2/28, 7%) vs. (0/28, 0%) through the cord (although statistical significance could not be determined because there were no low through-the-cord measurements). CONCLUSIONS: For the detection of low amniotic fluid volumes, the AFI to the cord is better than through the cord. Measurement to the cord and through the cord had similar accuracy for both the AFI and SDP techniques in normal and high dye-determined amniotic fluid volumes.


Assuntos
Líquido Amniótico/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Cordão Umbilical/diagnóstico por imagem , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Valores de Referência , Pesos e Medidas
14.
In Vitr Mol Toxicol ; 14(1): 43-51, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11689155

RESUMO

Environmental estrogens are suspected of being involved in the current increase in the incidence of human reproductive malfunctions, such as a decrease in male reproductive capacity and an increased incidence of breast cancer in women. The influences of these compounds have been proposed to be mediated through binding to macromolecules, such as estrogen receptor alpha or beta. In this study we examined whether the low-affinity Type II estrogen binding site (Type II EBS), originally identified in the rat uterus, is a possible mediator of environmental estrogens such as bisphenol A (BPA). Analysis of BPA's binding to an enriched fraction of Type II EBS, using a competition assay, indicated that BPA was able to compete with estradiol in binding to this site. At a concentration of 10-15 microM (comparable to that required to induce uterine proliferation), BPA inhibited the binding of estradiol to Type II EBS by greater than 50%. The binding affinity of BPA for the Type II EBS was only 8-10-fold lower than that of the synthetic estrogen diethylstilbestrol. The binding of BPA to Type II EBS appeared specific to BPA, in that endosulfan, another environmental estrogen, failed to displace estradiol from the site. A comparison of the relative binding affinities of BPA for rat uterine estrogen receptor alpha to that of the Type II EBS implies that BPA preferentially binds to the Type II EBS.


Assuntos
Estrogênios não Esteroides/metabolismo , Fenóis/metabolismo , Receptores de Estrogênio/metabolismo , Útero/metabolismo , Animais , Compostos Benzidrílicos , Ligação Competitiva , Divisão Celular/efeitos dos fármacos , Dietilestilbestrol/metabolismo , Relação Dose-Resposta a Droga , Endossulfano/metabolismo , Estradiol/metabolismo , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Estrogênios não Esteroides/farmacologia , Feminino , Técnicas In Vitro , Fenóis/farmacologia , Gravidez , Ratos , Útero/efeitos dos fármacos
15.
AJNR Am J Neuroradiol ; 20(8): 1429-34, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10512224

RESUMO

BACKGROUND AND PURPOSE: Despite ongoing clinical suspicion regarding the relationship between sacroiliac joint (SIJ) dysfunction and lower extremity symptoms, there is a paucity of scientific literature addressing this topic. The purpose of this study was to describe patterns of contrast extravasation during SIJ arthrography and postarthrography CT in patients with lower back pain and to determine whether there are pathways of communication between the SIJ and nearby neural structures. METHODS: Fluoroscopically guided SIJ arthrography was performed on 76 SIJs. After the injection of contrast medium, anteroposterior, lateral, and oblique radiographs as well as 5-mm contiguous axial and direct coronal CT images were obtained. Contrast extravasation patterns were recorded for each joint. These observations included a search for contrast extravasation from the SIJ that contacted nearby lumbosacral nerve roots or structures of the plexus. RESULTS: Sixty-one percent of all joints studied revealed one of five contrast extravasation patterns. Three of these observed patterns show a pathway of communication between the SIJ and nearby neural structures. These included posterior extravasation into the dorsal sacral foramina, superior recess extravasation at the sacral alar level to the fifth lumbar epiradicular sheath, and ventral extravasation to the lumbosacral plexus. CONCLUSION: Three pathways between the SIJ and neural structures exist.


Assuntos
Artrografia , Dor Lombar/diagnóstico por imagem , Plexo Lombossacral/diagnóstico por imagem , Articulação Sacroilíaca/inervação , Raízes Nervosas Espinhais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Meios de Contraste , Extravasamento de Materiais Terapêuticos e Diagnósticos/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Articulação Sacroilíaca/diagnóstico por imagem
16.
Child Dev ; 69(1): 192-218, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9499567

RESUMO

Two studies designed to (1) explore measurement issues for the construct domains of social competence and social support and (2) test a model relating social competence to social support and to child-parent attachment for low-income (primarily African American) preschool children attending Head Start are reported. In Study 1, the definition, measurement, and structure of the social competence construct are evaluated in 2 samples of children. For Study 1A, 167 4-year-old children were assessed with a battery of observation, interview, and Q-sort measures. Relations among the measures suggested a hierarchical structure that was tested using a structural equation model. Results from the analysis supported the conjecture that social competence should be viewed as a hierarchically organized construct. In Study 1B, the model was tested again for a group of 3- and 4-year-old children (n = 265), using a modified set of measures. The general structure of the model from Study 1A was reproduced in this independent sample, although paths from the second-order factor to lower-order factors were not perfectly coordinated across samples. In Study 2, data for a subset of the children in Study 1B (n = 182), gathered with respect to features of their social networks, were examined to assess the structure of their social support networks. Descriptive and structural equation analyses are reported. Sixty-nine of these children were observed at home with their mothers and described using the Waters Attachment Q-sort. A structural equation model testing relations consistent with causal pathways from attachment security to both social support networks and to social competence and from the social support network variable to social competence with peers fit these data with a high degree of confidence. Subsequent analyses locating social competence as antecedent to attachment security were not significant. We conclude that the construct domains of social competence and social support networks can be meaningfully measured for preschool children and that individual differences with respect to these construct domains are related to child-parent relationship qualities.


Assuntos
Desenvolvimento Infantil/fisiologia , Pré-Escolar , Apego ao Objeto , Percepção Social , Apoio Social , Feminino , Humanos , Masculino , Relações Pais-Filho
17.
Science ; 260(5111): 1101-4, 1993 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-17806338

RESUMO

Doubled atmospheric carbon dioxide concentration in a global coupled ocean-atmosphere climate model produced increased surface temperatures and evaporation and greater mean precipitation in the south Asian summer monsoon region. As a partial consequence, interannual variability of area-averaged monsoon rainfall was enhanced. Consistent with the climate sensitivity results from the model, observations showed a trend of increased interannual variability of Indian monsoon precipitation associated with warmer land and ocean temperatures in the monsoon region.

18.
Science ; 253(5022): 888-92, 1991 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-17751825

RESUMO

Snow feedback is expected to amplify global warming caused by increasing concentrations of atmospheric greenhouse gases. The conventional explanation is that a warmer Earth will have less snow cover, resulting in a darker planet that absorbs more solar radiation. An intercomparison of 17 general circulation models, for which perturbations of sea surface temperature were used as a surrogate climate change, suggests that this explanation is overly simplistic. The results instead indicate that additional amplification or moderation may be caused both by cloud interactions and longwave radiation. One measure of this net effect of snow feedback was found to differ markedly among the 17 climate models, ranging from weak negative feedback in some models to strong positive feedback in others.

19.
Int J Group Psychother ; 41(1): 79-96, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2007532

RESUMO

This paper discusses how the application of object relations theory to clinical intervention has extended the application of psychoanalytic group psychotherapy to more severely disturbed patients. The author suggests how to structure the group based on individual and group needs. Clinical issues are presented, including the group as a container, communication peculiarities, and psychotic response to separation, sexuality, and interpretation.


Assuntos
Apego ao Objeto , Terapia Psicanalítica , Psicoterapia de Grupo/métodos , Transtornos Psicóticos/terapia , Adulto , Comunicação , Feminino , Estrutura de Grupo , Humanos , Relações Interpessoais , Masculino
20.
Science ; 245(4917): 513-6, 1989 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-17750262

RESUMO

Understanding the cause of differences among general circulation model projections of carbon dioxide-induced climatic change is a necessary step toward improving the models. An intercomparison of 14 atmospheric general circulation models, for which sea surface temperature perturbations were used as a surrogate climate change, showed that there was a roughly threefold variation in global climate sensitivity. Most of this variation is attributable to differences in the models' depictions of cloud-climate feedback, a result that emphasizes the need for improvements in the treatment of clouds in these models if they are ultimately to be used as climatic predictors.

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