941 resultados para low level laser therapy
Resumo:
I. Foehn winds of southern California.
An investigation of the hot, dry and dust laden winds
occurring in the late fall and early winter in the Los Angeles
Basin and attributed in the past to the influences of the desert
regions to the north revealed that these currents were of a
foehn nature. Their properties were found to be entirely due
to dynamical heating produced in the descent from the high level
areas in the interior to the lower Los Angeles Basin. Any dust
associated with the phenomenon was found to be acquired from the
Los Angeles area rather than transported from the desert. It was
found that the frequency of occurrence of a mild type foehn of this
nature during this season was sufficient to warrant its classification
as a winter monsoon. This results from the topography of
the Los Angeles region which allows an easy entrance to the air
from the interior by virtue of the low level mountain passes north
of the area. This monsoon provides the mild winter climate of
southern California since temperatures associated with the foehn
currents are far higher than those experienced when maritime air
from the adjacent Pacific Ocean occupies the region.
II. Foehn wind cyclo-genesis.
Intense anticyclones frequently build up over the high level
regions of the Great Basin and Columbia Plateau which lie between
the Sierra Nevada and Cascade Mountains to the west and the Rocky
Mountains to the east. The outflow from these anticyclones produce
extensive foehns east of the Rockies in the comparatively low
level areas of the middle west and the Canadian provinces of
Alberta and Saskatchewan. Normally at this season of the year very
cold polar continental air masses are present over this territory
and with the occurrence of these foehns marked discontinuity surfaces
arise between the warm foehn current, which is obliged to slide over
a colder mass, and the Pc air to the east. Cyclones are
easily produced from this phenomenon and take the form of unstable
waves which propagate along the discontinuity surface between the
two dissimilar masses. A continual series of such cyclones was
found to occur as long as the Great Basin anticyclone is maintained
with undiminished intensity.
III. Weather conditions associated with the Akron disaster.
This situation illustrates the speedy development and
propagation of young disturbances in the eastern United States
during the spring of the year under the influence of the conditionally
unstable tropical maritime air masses which characterise the
region. It also furnishes an excellent example of the superiority
of air mass and frontal methods of weather prediction for aircraft
operation over the older methods based upon pressure distribution.
IV. The Los Angeles storm of December 30, 1933 to January 1, 1934.
This discussion points out some of the fundamental interactions
occurring between air masses of the North Pacific Ocean in connection
with Pacific Coast storms and the value of topographic and
aerological considerations in predicting them. Estimates of rainfall
intensity and duration from analyses of this type may be made and
would prove very valuable in the Los Angeles area in connection with
flood control problems.
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The epoch of reionization remains one of the last uncharted eras of cosmic history, yet this time is of crucial importance, encompassing the formation of both the first galaxies and the first metals in the universe. In this thesis, I present four related projects that both characterize the abundance and properties of these first galaxies and uses follow-up observations of these galaxies to achieve one of the first observations of the neutral fraction of the intergalactic medium during the heart of the reionization era.
First, we present the results of a spectroscopic survey using the Keck telescopes targeting 6.3 < z < 8.8 star-forming galaxies. We secured observations of 19 candidates, initially selected by applying the Lyman break technique to infrared imaging data from the Wide Field Camera 3 (WFC3) onboard the Hubble Space Telescope (HST). This survey builds upon earlier work from Stark et al. (2010, 2011), which showed that star-forming galaxies at 3 < z < 6, when the universe was highly ionized, displayed a significant increase in strong Lyman alpha emission with redshift. Our work uses the LRIS and NIRSPEC instruments to search for Lyman alpha emission in candidates at a greater redshift in the observed near-infrared, in order to discern if this evolution continues, or is quenched by an increase in the neutral fraction of the intergalactic medium. Our spectroscopic observations typically reach a 5-sigma limiting sensitivity of < 50 AA. Despite expecting to detect Lyman alpha at 5-sigma in 7-8 galaxies based on our Monte Carlo simulations, we only achieve secure detections in two of 19 sources. Combining these results with a similar sample of 7 galaxies from Fontana et al. (2010), we determine that these few detections would only occur in < 1% of simulations if the intrinsic distribution was the same as that at z ~ 6. We consider other explanations for this decline, but find the most convincing explanation to be an increase in the neutral fraction of the intergalactic medium. Using theoretical models, we infer a neutral fraction of X_HI ~ 0.44 at z = 7.
Second, we characterize the abundance of star-forming galaxies at z > 6.5 again using WFC3 onboard the HST. This project conducted a detailed search for candidates both in the Hubble Ultra Deep Field as well as a number of additional wider Hubble Space Telescope surveys to construct luminosity functions at both z ~ 7 and 8, reaching 0.65 and 0.25 mag fainter than any previous surveys, respectively. With this increased depth, we achieve some of the most robust constraints on the Schechter function faint end slopes at these redshifts, finding very steep values of alpha_{z~7} = -1.87 +/- 0.18 and alpha_{z~8} = -1.94 +/- 0.23. We discuss these results in the context of cosmic reionization, and show that given reasonable assumptions about the ionizing spectra and escape fraction of ionizing photons, only half the photons needed to maintain reionization are provided by currently observable galaxies at z ~ 7-8. We show that an extension of the luminosity function down to M_{UV} = -13.0, coupled with a low level of star-formation out to higher redshift, can fit all available constraints on the ionization history of the universe.
Third, we investigate the strength of nebular emission in 3 < z < 5 star-forming galaxies. We begin by using the Infrared Array Camera (IRAC) onboard the Spitzer Space Telescope to investigate the strength of H alpha emission in a sample of 3.8 < z < 5.0 spectroscopically confirmed galaxies. We then conduct near-infrared observations of star-forming galaxies at 3 < z < 3.8 to investigate the strength of the [OIII] 4959/5007 and H beta emission lines from the ground using MOSFIRE. In both cases, we uncover near-ubiquitous strong nebular emission, and find excellent agreement between the fluxes derived using the separate methods. For a subset of 9 objects in our MOSFIRE sample that have secure Spitzer IRAC detections, we compare the emission line flux derived from the excess in the K_s band photometry to that derived from direct spectroscopy and find 7 to agree within a factor of 1.6, with only one catastrophic outlier. Finally, for a different subset for which we also have DEIMOS rest-UV spectroscopy, we compare the relative velocities of Lyman alpha and the rest-optical nebular lines which should trace the cites of star-formation. We find a median velocity offset of only v_{Ly alpha} = 149 km/s, significantly less than the 400 km/s observed for star-forming galaxies with weaker Lyman alpha emission at z = 2-3 (Steidel et al. 2010), and show that this decrease can be explained by a decrease in the neutral hydrogen column density covering the galaxy. We discuss how this will imply a lower neutral fraction for a given observed extinction of Lyman alpha when its visibility is used to probe the ionization state of the intergalactic medium.
Finally, we utilize the recent CANDELS wide-field, infra-red photometry over the GOODS-N and S fields to re-analyze the use of Lyman alpha emission to evaluate the neutrality of the intergalactic medium. With this new data, we derive accurate ultraviolet spectral slopes for a sample of 468 3 < z < 6 star-forming galaxies, already observed in the rest-UV with the Keck spectroscopic survey (Stark et al. 2010). We use a Bayesian fitting method which accurately accounts for contamination and obscuration by skylines to derive a relationship between the UV-slope of a galaxy and its intrinsic Lyman alpha equivalent width probability distribution. We then apply this data to spectroscopic surveys during the reionization era, including our own, to accurately interpret the drop in observed Lyman alpha emission. From our most recent such MOSFIRE survey, we also present evidence for the most distant galaxy confirmed through emission line spectroscopy at z = 7.62, as well as a first detection of the CIII]1907/1909 doublet at z > 7.
We conclude the thesis by exploring future prospects and summarizing the results of Robertson et al. (2013). This work synthesizes many of the measurements in this thesis, along with external constraints, to create a model of reionization that fits nearly all available constraints.
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A presente dissertação tem como tema a gestão de saúde, segurança, meio ambiente e responsabilidade social em micro e pequenas empresas recicladoras de plásticos PEBD e PET no Estado do Rio de Janeiro. A reciclagem de plástico contribui para minimizar os resíduos sólidos gerados pelos processos industriais. O objetivo geral deste estudo é verificar como as atividades de reciclagem impactam na saúde e na segurança do trabalhador e levantar algumas questões relacionadas com a responsabilidade sócio-ambiental, com destaque para o atendimento às normas regulamentadoras, legislação de saúde, segurança e meio ambiente aplicável e sistemas de gestão. Para atingir tal objetivo, a metodologia do presente estudo foi dividida em: pesquisa bibliográfica, elaborada através de consultas a livros, a artigos, a legislação e a bancos de dados de reconhecida credibilidade; elaboração de um questionário direcionado; visitas técnicas, e entrevistas com os encarregados ou donos das empresas, a fim de obter dados para avaliar as condições de trabalho relativas à saúde e segurança, meio ambiente e responsabilidade social. Durante esta etapa foram visitadas quatro recicladoras de plástico, todas situadas no Estado do Rio de Janeiro, sendo três do segmento de PEBD e uma de PET. Os resultados obtidos mostram que, numa avaliação global, apenas 24% dos itens avaliados foram atendidos na sua íntegra, o que demonstra um baixo índice de atendimento às questões relativas à saúde, segurança e meio ambiente e responsabilidade social. Nas avaliações individuais destes mesmos itens constatou-se que o atendimento foi de 38%, 10% e 54%, respectivamente. Enfim, o presente estudo mostra que há necessidade de maior atenção aos requisitos relativos à saúde e segurança do trabalhador, ao meio ambiente e às questões sociais, em função dos riscos do processo de produção do plástico reciclado
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As the worldwide prevalence of diabetes mellitus continues to increase, diabetic retinopathy remains the leading cause of visual impairment and blindness in many developed countries. Between 32 to 40 percent of about 246 million people with diabetes develop diabetic retinopathy. Approximately 4.1 million American adults 40 years and older are affected by diabetic retinopathy. This glucose-induced microvascular disease progressively damages the tiny blood vessels that nourish the retina, the light-sensitive tissue at the back of the eye, leading to retinal ischemia (i.e., inadequate blood flow), retinal hypoxia (i.e., oxygen deprivation), and retinal nerve cell degeneration or death. It is a most serious sight-threatening complication of diabetes, resulting in significant irreversible vision loss, and even total blindness.
Unfortunately, although current treatments of diabetic retinopathy (i.e., laser therapy, vitrectomy surgery and anti-VEGF therapy) can reduce vision loss, they only slow down but cannot stop the degradation of the retina. Patients require repeated treatment to protect their sight. The current treatments also have significant drawbacks. Laser therapy is focused on preserving the macula, the area of the retina that is responsible for sharp, clear, central vision, by sacrificing the peripheral retina since there is only limited oxygen supply. Therefore, laser therapy results in a constricted peripheral visual field, reduced color vision, delayed dark adaptation, and weakened night vision. Vitrectomy surgery increases the risk of neovascular glaucoma, another devastating ocular disease, characterized by the proliferation of fibrovascular tissue in the anterior chamber angle. Anti-VEGF agents have potential adverse effects, and currently there is insufficient evidence to recommend their routine use.
In this work, for the first time, a paradigm shift in the treatment of diabetic retinopathy is proposed: providing localized, supplemental oxygen to the ischemic tissue via an implantable MEMS device. The retinal architecture (e.g., thickness, cell densities, layered structure, etc.) of the rabbit eye exposed to ischemic hypoxic injuries was well preserved after targeted oxygen delivery to the hypoxic tissue, showing that the use of an external source of oxygen could improve the retinal oxygenation and prevent the progression of the ischemic cascade.
The proposed MEMS device transports oxygen from an oxygen-rich space to the oxygen-deficient vitreous, the gel-like fluid that fills the inside of the eye, and then to the ischemic retina. This oxygen transport process is purely passive and completely driven by the gradient of oxygen partial pressure (pO2). Two types of devices were designed. For the first type, the oxygen-rich space is underneath the conjunctiva, a membrane covering the sclera (white part of the eye), beneath the eyelids and highly permeable to oxygen in the atmosphere when the eye is open. Therefore, sub-conjunctival pO2 is very high during the daytime. For the second type, the oxygen-rich space is inside the device since pure oxygen is needle-injected into the device on a regular basis.
To prevent too fast or too slow permeation of oxygen through the device that is made of parylene and silicone (two widely used biocompatible polymers in medical devices), the material properties of the hybrid parylene/silicone were investigated, including mechanical behaviors, permeation rates, and adhesive forces. Then the thicknesses of parylene and silicone became important design parameters that were fine-tuned to reach the optimal oxygen permeation rate.
The passive MEMS oxygen transporter devices were designed, built, and tested in both bench-top artificial eye models and in-vitro porcine cadaver eyes. The 3D unsteady saccade-induced laminar flow of water inside the eye model was modeled by computational fluid dynamics to study the convective transport of oxygen inside the eye induced by saccade (rapid eye movement). The saccade-enhanced transport effect was also demonstrated experimentally. Acute in-vivo animal experiments were performed in rabbits and dogs to verify the surgical procedure and the device functionality. Various hypotheses were confirmed both experimentally and computationally, suggesting that both the two types of devices are very promising to cure diabetic retinopathy. The chronic implantation of devices in ischemic dog eyes is still underway.
The proposed MEMS oxygen transporter devices can be also applied to treat other ocular and systemic diseases accompanied by retinal ischemia, such as central retinal artery occlusion, carotid artery disease, and some form of glaucoma.
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Pyrrole–Imidazole polyamides are programmable, cell-permeable small molecules that bind in the minor groove of double-stranded DNA sequence-specifically. Polyamide binding has been shown to alter the local helical structure of DNA, disrupt protein-DNA interactions, and modulate endogenous gene expression. Py–Im polyamides targeted to the androgen receptor-DNA interface have been observed to decrease expression of androgen-regulated genes, upregulate p53, and induce apoptosis in a hormone-sensitive prostate cancer cell line. Here we report that androgen response element (ARE)-targeted polyamides induced DNA replication stress in a hormone-insensitive prostate cancer cell line. The ATR checkpoint kinase was activated in response to this stress, causing phosphorylation of MCM2, and FANCD2 was monoubiquitinated. Surprisingly, little single-stranded DNA was exhibited, and the ATR targets RPA2 and Chk1 were not phosphorylated. We conclude that polyamide induces relatively low level replication stress, and suggest inhibition of the replicative helicase as a putative mechanism based on in vitro assays. We also demonstrate polyamide-induced inhibition of DNA replication in cell free extracts from X. laevis oocytes. In this system, inhibition of chromatin decondensation is observed, preventing DNA replication initiation. Finally, we show that Py-Im polyamides targeted to the ARE and ETS binding sequence downregulate AR- and ERG-driven signaling in a prostate cancer cell line harboring the TMPRSS2-ERG fusion. In a mouse xenograft model, ARE-targeted polyamide treatment reduced growth of the tumor.
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Thermodynamical fluctuations in temperature and position exist in every physical system, and show up as a fundamental noise limit whenever we choose to measure some quantity in a laboratory environment. Thermodynamical fluctuations in the position of the atoms in the dielectric coatings on the mirrors for optical cavities at the forefront of precision metrology (e.g., LIGO, the cavities which probe atomic transitions to define the second) are a current limiting noise source for these experiments, and anything which involves locking a laser to an optical cavity. These thermodynamic noise sources scale physical geometry of experiment, material properties (such as mechanical loss in our dielectric coatings), and temperature. The temperature scaling provides a natural motivation to move to lower temperatures, with a potential huge benefit for redesigning a room temperature experiment which is limited by thermal noise for cryogenic operation.
We design, build, and characterize a pair of linear Fabry-Perot cavities to explore limitations to ultra low noise laser stabilization experiments at cryogenic temperatures. We use silicon as the primary material for the cavity and mirrors, due to a zero crossing in its linear coefficient of thermal expansion (CTE) at 123 K, and other desirable material properties. We use silica tantala coatings, which are currently the best for making high finesse low noise cavities at room temperature. The material properties of these coating materials (which set the thermal noise levels) are relatively unknown at cryogenic temperatures, which motivates us to study them at these temperatures. We were not able to measure any thermal noise source with our experiment due to excess noise. In this work we analyze the design and performance of the cavities, and recommend a design shift from mid length cavities to short cavities in order to facilitate a direct measurement of cryogenic coating noise.
In addition, we measure the cavities (frequency dependent) photo-thermal response. This can help characterize thermooptic noise in the coatings, which is poorly understood at cryogenic temperatures. We also explore the feasibility of using the cavity to do macroscopic quantum optomechanics such as ground state cooling.
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O presente trabalho investigou a relação entre a baixa escolaridade e a prática de atos infracionais, procurando entender alguns fatores associados ao fracasso escolar de adolescentes que passaram pela Vara da Infância e da Juventude de Duque de Caxias. Em especial, buscou entender o fenômeno da exclusão social como elemento relevante relacionado ao tema fracasso escolar: em que medida é possível afirmar que a baixa escolaridade coloca estes adolescentes em situação de vulnerabilidade em relação a práticas ilícitas? Os dados da pesquisa foram obtidos por meio de um questionário e de entrevistas aplicados aos adolescentes infratores seus responsáveis. No total, a pesquisa trabalhou com as respostas de 262 adolescentes infratores que tiveram passagem pela Justiça Infanto-Juvenil de Duque de Caxias, no período compreendido entre maio de 2006 e maio de 2008. Esta pesquisa teve por base principal as idéias de Maria Helena Patto, a respeito da construção do fracasso escolar; Miriam Abramovay, com sua contribuição sobre vulnerabilidade social; Aldaíza Spozati e Miguel Arroyo, que alertam para as questões relacionadas ao acesso, permanência, sucesso e não-fracasso na escola; Alex Eduardo Gallo e Lúcia Cavalcanti de Albuquerque Williams, a respeito do perfil dos adolescentes infratores. A pesquisa revelou que a baixa escolaridade coloca os adolescentes em situação de vulnerabilidade social e que a escola pode ser um fator de proteção à criminalidade.
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An atomic force microscope (AFM) assisted surface plasmons leakage radiation photolithography technique has been numerically demonstrated by using two-dimensional finite-difference time-domain (2D-FDTD) method. With the aid of a metallic AFM tip, particular characteristic of the Kretstchmann configuration to excite surface plasmons (SPs) is utilized to achieve large-area patterns with high spatial resolution and contrast, the photoresist could be exposed with low power laser due to the remarkable local field enhancement at the metal/dielectric interface and the resonant localized SPs modes near the tip. Good tolerance on the film thickness and incident angle has been obtained, which provides a good practicability for experiments. This photolithography technique proposed here can realize large-area, high-resolution, high-contrast, nondestructive, arbitrary-structure fabrication of nanoscale devices. (c) 2007 Elsevier B.V. All rights reserved.
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To optimize the performance of longitudinally pumped Yb^(3+):Y2O3 ceramic lasers, cavity parameters such as material length and output coupler transmission at a certain laser output power are calculated numerically using quasi-three-level laser model. The results show great potential of Yb^(3+):Y2O3 ceramics for highly efficient diode-pumped solid-state lasers.
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Essa dissertação objetiva oferecer uma contribuição acadêmica sobre o nível de transparência pública federal nos relatórios de gestão anuais e os incentivos (político, institucional, governamental, social e financeiro) associados à divulgação da informação. Aborda-se, a perspectiva do conflito de agência, assimetria informacional e public accountability na divulgação da informação pública, isto é, os gestores governamentais tendem a disponibilizar uma informação assimétrica ao cidadão. A pesquisa é empírico-analítica com regressão linear múltipla e análise de corte transversal nos relatórios de gestão de 2010 de 115 entes públicos federais. Para tanto foi construído um índice de transparência pública federal (total, obrigatório e voluntário) dicotômico (binário) e policotômico (ponderado), baseado em estudos anteriores e na legislação nacional, adaptado ao cenário brasileiro. Os resultados apontam um baixo nível de transparência pública federal (50%) dos itens de evidenciação, deficiência de compliance com as práticas de evidenciação obrigatória (80%) e baixa aderência às práticas de evidenciação voluntária (19%). Ademais se verificou uma uniformidade na divulgação da informação pública (total, obrigatória e voluntária) entre os entes públicos da administração indireta (autarquias 54% e fundações 55%), mas diferenças estatísticas significativas quando considerados estes e os entes da administração direta (órgãos públicos 46%), que tendem a divulgar menos informação. Relativo aos incentivos se observa uma relação positiva do tipo do ente (incentivo governamental), da acessibilidade (incentivo social) e da demografia de pessoal (incentivo institucional) com o índice de transparência pública federal, enquanto a burocracia pública (incentivo governamental) apresenta uma relação negativa. Todavia o porte (incentivo político), tamanho do núcleo de gestão (incentivo institucional), receita orçamentária e dependência federal (incentivo financeiro) não apresentaram relação com o índice. Assim, a contribuição do estudo é revelar o atual estágio da transparência pública dos entes públicos federais, bem como os incentivos associados, e estas informações, podem ser oportunidades de melhorias na evidenciação da informação pública nos relatórios de gestão anuais.
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For the first time, a high optical quality 10 at.% Yb3+-doped gadolinium oxyorthosilicate laser crystal Gd2SiO5 (GSO) was grown by the Czochralski (Cz) method. The segregation coefficient of Yb3+ was studied by the inductively coupled plasma atomic emission spectrometer (ICP-AES) method. The crystal structure has monoclinic symmetry with space group P2(1)/c; this was determined by means of an x-ray diffraction analysis. The absorption spectra, fluorescence spectra and fluorescence decay curves of Yb3+ ions in a GSO crystal at room temperature were also studied. Then, the spectroscopic parameters of Yb:GSO were calculated. The advantages of the Yb:GSO crystal include high crystal quality, quasi-four-level laser operating scheme, high absorption cross-sections and particularly broad emission bandwidth (similar to 72 nm). The results indicated that the Yb:GSO crystal seemed to be a very promising laser gain medium in diode-pumped femtosecond laser and tunable solid state laser applications when LD pumped at 940 and 980 nm.
Resumo:
CASTELLANO. Alemania, un país muy afectado tras el nazismo y las diferentes guerras en las cuales se vio involucrado, adoptó una Economía Social de Mercado (ESM) en 1948, que le permitió abrir sus puertas hacia la internacionalización, lo cual había estado fuertemente regulado hasta entonces. Esta apertura de fronteras ha favorecido al comercio exterior el cual está muy desarrollado. Además, una moderada inflación, un bajo nivel de deuda pública, alta cualificación de la población, el potente desarrollo industrial manufacturero y su capacidad de recuperación de la crisis económica que estalló en 2007, entre otros, hace de Alemania un país muy próspero. España, tras su recuperación de la época del franquismo la cual había castigado de forma severa a este país, se recuperó hasta niveles superiores a Alemania en cuestión de confianza empresarial. En cambio, en 2007, momento de estallido de crisis, la producción de varios sectores se vio muy reducida (principalmente el sector de la construcción), la tasa de desempleo aumentó de forma descontrolada… Actualmente, este país se encuentra en proceso de recuperación el cual se basa mucho en el turismo y por consiguiente en el sector servicios que año tras año ha ido evolucionando hasta convertirse en uno de los motores de esta economía.
Resumo:
通过助熔剂固相反应法制备了5%Yb掺杂的硫氧化钇(Y2O2S)粉体。通过对其漫反射光谱和荧光光谱的测量，估算得Yb3+离子在Y2O2S晶格中的晶场分裂。由光谱数据计算得Yb3+离子的2F7/2能级在Y2O2S中的分裂值为709cm-1，适合于Yb3+离子的准三能级的激光运转。由5％Yb：Y2O2S的发射光谱拟合得出其峰位，峰高及峰宽。为了比较，相关的5％Yb：YAG的数据也被给出。
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201 p.
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principalmente pelo baixo grau de complexidade de especialização, escassez de caracteres distintivos e a elevada plasticidade morfológica. A partir do século XIX emergiram classificações mais robustas. O que conhecemos hoje como Ordem Poecilosclerida só começou a ser delineado pela iniciativa de Zittel (1878) com o reconhecimento de Monaxonida, ou seja, reconhecimento de um padrão de simetria nas categorias de espículas. Ridley e Dendy (1887) apresentaram uma nova classificação para as esponjas do grupo Monaxonida utilizada por Topsent (1894) para criação da Familia Poeciloscleridae, eregida a ordem por este último autor em 1928, enfatizando a presença das quelas como microscleras. Posteriormente, van Soest (1984) e Bergquist e Fromont (1988) empreenderam discussões dessa classificação com base em uma perspectiva filogenética. Uma classificação robusta e de consenso só foi conseguida a partir dos trabalhos de Hajdu e colaboradores (1994a, 1994b) e Hajdu (1994, 1995), com o estabelecimento das Subordens: Mycalina, Myxillina e Microcionina. Apesar disso, as relações internas das famílias da Subordem Mycalina permaneciam com dúvidas, principalmente no tocante à inclusão de Podospongiidae, Isodictyidae, e a relação de Poecilosclerida com a Ordem Haplosclerida. Neste trabalho foi proposto a revisão da classificação da Subordem Mycalina com base em dados morfológicos e moleculares. Foram feitas análises filogenéticas em três níveis taxonômicos, espécie, gênero e família, com base em dados morfológicos. Além disso, foi feita uma análise filogenética molecular utilizando sequências parciais da subunidade maior do RNA ribossomal (LSU do RNAr). As amostras de Mycalina foram amplificadas via PCR e posteriormente sequenciadas. Com base nestes resultados foi concluído que: as Familias Cladorhizidae, Guitarridae, Mycalidae e Hamacanthidae são monofiléticas. Para esta última foi confirmada a série de transformação sigmancistra > cirtancistra > diâncistra > clavidisco. A posição da Familia Podospongiidae dentro de Mycalina está bem corroborada, porém, precisa ser melhor estudada com dados moleculares para determinar, ou não, o seu monofiletismo. A Familia Esperiopsidae precisa ser melhor estudada com base em dados morfológicos e o gênero Amphilectus precisa ser revisado, provavelmente uma parte deste estaria melhor alocado em Haplosclerida junto com Isodictyidae. A Familia Desmacellidae não é monofilética, bem como Biemna e Neofibularia, provavelmente, não são Poecilosclerida e deveriam ser transferidas para uma posição próxima de Tetractinellida. Desmacella provavelmente é uma Mycalina com posição basal na Subordem. Os demais gêneros precisam ser estudados com base em dados moleculares. A Ordem Haplosclerida provavelmente é o grupo irmão de Poecilosclerida e a série de transformação sigmas > quelas foi confirmada com base em dados morfológicos e moleculares. A Subordem Mycalina não é monofilética como definida em Hajdu e van Soest (2002a). Palavras-chave: Sistemática. Porifera. Evolução.
