Synthesis and matrix isolated photolysis of 2,3-dimethylbicyclo [2.2.0]hexa-2,5-diene-1,4-dicarboxylic acid anhydride: a potential percursor to 2,3-dimethyl-1,4-dehydrobenzene

The synthesis of the first member of a new class of Dewar benzenes has been achieved. The synthesis of 2,3- dimethylbicyclo[2.2.0]hexa-2,5-diene-1, 4-dicarboxylic acid and its anhydride are described. Dibromomaleic anhydride and dichloroethylene were found to add efficiently in a photochemical [2+2] cycloaddition to produce 1,2-dibromo- 3,4-dichlorocyclobutane-1,2-dicarboxylic acid. Removal of the bromines with tin/copper couple yielded dichloro- cyclobutenes which added to 2-butyne under photochemical conditions to yield 5,6-dichloro-2,3-dimethylbicyclo [2.2.0] hex-2-ene dicarboxylic acids. One of the three possible isomers yielded a stable anhydride which could be dechlorinated using triphenyltin radicals generated by the photolysis of hexaphenylditin.

Photolysis of argon matrix isolated 2,3-dimethylbicyclo [2.2.0]hexa-2, 5-diene-1,4-dicarboxylic acid anhydride produced traces whose strongest bands in the infrared were at 3350 and 600 cm^(-1). This suggested the formation of terminal acetylenes. The spectra of argon matrix isolated E- and Z- 3,4-dimethylhexa-1,5-diyne-3-ene and cis-and trans-octa- 2,6-diyne-4-ene were compared with the spectrum of the photolysis products. Possibly all four diethynylethylenes were present in the anhydride photolysis products. Gas chromatograph-mass spectral analysis of the volatiles from the anhydride photolysis again suggested, but did not confirm, the presence of the diethynylethylenes.

An economic air pollution control model-application : photochemical smog in Los Angeles County in 1975

An economic air pollution control model, which determines the least cost of reaching various air quality levels, is formulated. The model takes the form of a general, nonlinear, mathematical programming problem. Primary contaminant emission levels are the independent variables. The objective function is the cost of attaining various emission levels and is to be minimized subject to constraints that given air quality levels be attained.

The model is applied to a simplified statement of the photochemical smog problem in Los Angeles County in 1975 with emissions specified by a two-dimensional vector, total reactive hydrocarbon, (RHC), and nitrogen oxide, (NO_x), emissions. Air quality, also two-dimensional, is measured by the expected number of days per year that nitrogen dioxide, (NO₂), and mid-day ozone, (O₃), exceed standards in Central Los Angeles.

The minimum cost of reaching various emission levels is found by a linear programming model. The base or "uncontrolled" emission levels are those that will exist in 1975 with the present new car control program and with the degree of stationary source control existing in 1971. Controls, basically "add-on devices", are considered here for used cars, aircraft, and existing stationary sources. It is found that with these added controls, Los Angeles County emission levels [(1300 tons/day RHC, 1000 tons /day NO_x) in 1969] and [(670 tons/day RHC, 790 tons/day NO_x) at the base 1975 level], can be reduced to 260 tons/day RHC (minimum RHC program) and 460 tons/day NO_x (minimum NO_x program).

"Phenomenological" or statistical air quality models provide the relationship between air quality and emissions. These models estimate the relationship by using atmospheric monitoring data taken at one (yearly) emission level and by using certain simple physical assumptions, (e. g., that emissions are reduced proportionately at all points in space and time). For NO₂, (concentrations assumed proportional to NO_x emissions), it is found that standard violations in Central Los Angeles, (55 in 1969), can be reduced to 25, 5, and 0 days per year by controlling emissions to 800, 550, and 300 tons /day, respectively. A probabilistic model reveals that RHC control is much more effective than NO_x control in reducing Central Los Angeles ozone. The 150 days per year ozone violations in 1969 can be reduced to 75, 30, 10, and 0 days per year by abating RHC emissions to 700, 450, 300, and 150 tons/day, respectively, (at the 1969 NO_x emission level).

The control cost-emission level and air quality-emission level relationships are combined in a graphical solution of the complete model to find the cost of various air quality levels. Best possible air quality levels with the controls considered here are 8 O₃ and 10 NO₂ violations per year (minimum ozone program) or 25 O₃ and 3 NO₂ violations per year (minimum NO₂ program) with an annualized cost of $230,000,000 (above the estimated $150,000,000 per year for the new car control program for Los Angeles County motor vehicles in 1975).

Avaliação nutricional do paciente com doença hepática crônica

Além de muito freqüente, a desnutrição associa-se a morbi/mortalidade em pacientes com doenças hepáticas crônicas. A avaliação do estado nutricional em hepatopatas é difícil pela sobrecarga hídrica e pela alteração na síntese protéica, fatores que alteram os parâmetros tradicionalmente usados na avaliação nutricional. Os objetivos são:a)avaliar o estado nutricional, através da AGS, antropometria, do escore de Mendenhall e da combinação de todos os instrumentos, em pacientes com doença hepática crônica; b)correlacionar o estado nutricional com a gravidade de doença hepática crônica; c)determinar a contribuição da dinamometria do aperto de mão para a avaliação do estado nutricional. Foram incluídos 305 pacientes portadores de doenças hepáticas crônicas, com idade de 18-80 anos, atendidos no ambulatório de doenças hepatobiliares do Hospital Universitátio Pedro Ernesto. A gravidade da doença hepática foi avaliada pela classificação de Child-Pugh e escore de Meld. Foram aferidos parâmetros antropométricos (peso, altura, índice de massa corporal, prega cutânea triciptal, circunferência do braço, circunferência muscular do braço), parâmetros bioquímicos (albumina e contagem total de linfócitos), Avaliação Global Subjetiva, escore de Mendenhall e força do aperto de mão pela dinamometria. Os valores da porcentagem de adequação dos parâmetros foram utilizados para a classificação da desnutrição. Consideramos todos os pacientes com porcentagens de adequação abaixo de 90% como desnutridos. Foi criado o escore risco de desnutrição que se caracterizou pela alteração em qualquer um dos parâmetros da avaliação nutricional. Cerca de 53% dos pacientes eram do sexo masculino, 43% portadores de cirrose hepática, 80% com etiologia viral e média de idade de 54 12 anos. Houve relação estatisticamente significativa entre a classificação funcional da doença hepática e a AGS, o escore de Mendenhall e o de risco de desnutrição. A avaliação isolada da antropometria não se correlacionou com a classificação funcional. Segundo a AGS, a prevalência de desnutrição foi de 10% na hepatopatia não cirrótica, 16% na cirrose compensada e 94% na cirrose descompensada. Segundo o escore de Mendenhall, as cifras foram de 31%, 38% e 56%, respectivamente. Segundo o novo escore, as cifras foram de 52%, 60% e 96%, respectivamente. Embora tenha havido uma redução estatisticamente significativa da força muscular com o agravamento do estado nutricional, não foi possível estabelecer um ponto de corte para os valores da dinamometria. A análise do desempenho do percentual de adequação da força muscular como critério diagnóstico de pacientes sob risco de desnutrição revelou provavelmente 56% de falso-positivos e 24% de falso-negativos. A grande variação na prevalência de desnutrição em pacientes com doença hepática depende do instrumento de avaliação nutricional usado e da classificação funcional da doença hepática. Não surpreendentemente, os escores combinados detectaram as maiores taxas de prevalência de desnutrição. Houve associação significativa entre o estado nutricional e a gravidade da doença hepática. O aumento das taxas de prevalência de desnutrição trazido pela dinamometria ocorreu às custas de resultados falso-positivos.

Quantum Interference and Entanglement of Surface Plasmons

Surface plasma waves arise from the collective oscillations of billions of electrons at the surface of a metal in unison. The simplest way to quantize these waves is by direct analogy to electromagnetic fields in free space, with the surface plasmon, the quantum of the surface plasma wave, playing the same role as the photon. It follows that surface plasmons should exhibit all of the same quantum phenomena that photons do, including quantum interference and entanglement.

Unlike photons, however, surface plasmons suffer strong losses that arise from the scattering of free electrons from other electrons, phonons, and surfaces. Under some circumstances, these interactions might also cause “pure dephasing,” which entails a loss of coherence without absorption. Quantum descriptions of plasmons usually do not account for these effects explicitly, and sometimes ignore them altogether. In light of this extra microscopic complexity, it is necessary for experiments to test quantum models of surface plasmons.

In this thesis, I describe two such tests that my collaborators and I performed. The first was a plasmonic version of the Hong-Ou-Mandel experiment, in which we observed two-particle quantum interference between plasmons with a visibility of 93 ± 1%. This measurement confirms that surface plasmons faithfully reproduce this effect with the same visibility and mutual coherence time, to within measurement error, as in the photonic case.

The second experiment demonstrated path entanglement between surface plasmons with a visibility of 95 ± 2%, confirming that a path-entangled state can indeed survive without measurable decoherence. This measurement suggests that elastic scattering mechanisms of the type that might cause pure dephasing must have been weak enough not to significantly perturb the state of the metal under the experimental conditions we investigated.

These two experiments add quantum interference and path entanglement to a growing list of quantum phenomena that surface plasmons appear to exhibit just as clearly as photons, confirming the predictions of the simplest quantum models.

Acceleration Sensing, Feedback Cooling, and Nonlinear Dynamics with Nanoscale Cavity-Optomechanical Devices

Light has long been used for the precise measurement of moving bodies, but the burgeoning field of optomechanics is concerned with the interaction of light and matter in a regime where the typically weak radiation pressure force of light is able to push back on the moving object. This field began with the realization in the late 1960's that the momentum imparted by a recoiling photon on a mirror would place fundamental limits on the smallest measurable displacement of that mirror. This coupling between the frequency of light and the motion of a mechanical object does much more than simply add noise, however. It has been used to cool objects to their quantum ground state, demonstrate electromagnetically-induced-transparency, and modify the damping and spring constant of the resonator. Amazingly, these radiation pressure effects have now been demonstrated in systems ranging 18 orders of magnitude in mass (kg to fg).

In this work we will focus on three diverse experiments in three different optomechanical devices which span the fields of inertial sensors, closed-loop feedback, and nonlinear dynamics. The mechanical elements presented cover 6 orders of magnitude in mass (ng to fg), but they all employ nano-scale photonic crystals to trap light and resonantly enhance the light-matter interaction. In the first experiment we take advantage of the sub-femtometer displacement resolution of our photonic crystals to demonstrate a sensitive chip-scale optical accelerometer with a kHz-frequency mechanical resonator. This sensor has a noise density of approximately 10 micro-g/rt-Hz over a useable bandwidth of approximately 20 kHz and we demonstrate at least 50 dB of linear dynamic sensor range. We also discuss methods to further improve performance of this device by a factor of 10.

In the second experiment, we used a closed-loop measurement and feedback system to damp and cool a room-temperature MHz-frequency mechanical oscillator from a phonon occupation of 6.5 million down to just 66. At the time of the experiment, this represented a world-record result for the laser cooling of a macroscopic mechanical element without the aid of cryogenic pre-cooling. Furthermore, this closed-loop damping yields a high-resolution force sensor with a practical bandwidth of 200 kHZ and the method has applications to other optomechanical sensors.

The final experiment contains results from a GHz-frequency mechanical resonator in a regime where the nonlinearity of the radiation-pressure interaction dominates the system dynamics. In this device we show self-oscillations of the mechanical element that are driven by multi-photon-phonon scattering. Control of the system allows us to initialize the mechanical oscillator into a stable high-amplitude attractor which would otherwise be inaccessible. To provide context, we begin this work by first presenting an intuitive overview of optomechanical systems and then providing an extended discussion of the principles underlying the design and fabrication of our optomechanical devices.

Computationally Guided Monomerization of Red Fluorescent Proteins of the Class Anthozoa

Red fluorescent proteins (RFPs) have attracted significant engineering focus because of the promise of near infrared fluorescent proteins, whose light penetrates biological tissue, and which would allow imaging inside of vertebrate animals. The RFP landscape, which numbers ~200 members, is mostly populated by engineered variants of four native RFPs, leaving the vast majority of native RFP biodiversity untouched. This is largely due to the fact that native RFPs are obligate tetramers, limiting their usefulness as fusion proteins. Monomerization has imposed critical costs on these evolved tetramers, however, as it has invariably led to loss of brightness, and often to many other adverse effects on the fluorescent properties of the derived monomeric variants. Here we have attempted to understand why monomerization has taken such a large toll on Anthozoa class RFPs, and to outline a clear strategy for their monomerization. We begin with a structural study of the far-red fluorescence of AQ143, one of the furthest red emitting RFPs. We then try to separate the problem of stable and bright fluorescence from the design of a soluble monomeric β-barrel surface by engineering a hybrid protein (DsRmCh) with an oligomeric parent that had been previously monomerized, DsRed, and a pre-stabilized monomeric core from mCherry. This allows us to use computational design to successfully design a stable, soluble, fluorescent monomer. Next we took HcRed, which is a previously unmonomerized RFP that has far-red fluorescence (λemission = 633 nm) and attempted to monomerize it making use of lessons learned from DsRmCh. We engineered two monomeric proteins by pre-stabilizing HcRed’s core, then monomerizing in stages, making use of computational design and directed evolution techniques such as error-prone mutagenesis and DNA shuffling. We call these proteins mGinger0.1 (λem = 637 nm / Φ = 0.02) and mGinger0.2 (λem = 631 nm Φ = 0.04). They are the furthest red first generation monomeric RFPs ever developed, are significantly thermostabilized, and add diversity to a small field of far-red monomeric FPs. We anticipate that the techniques we describe will be facilitate future RFP monomerization, and that further core optimization of the mGingers may allow significant improvements in brightness.

Expanding the Toolkit for Synthetic Biology: Frameworks for Native-like Non-natural Gene Circuits

Synthetic biology combines biological parts from different sources in order to engineer non-native, functional systems. While there is a lot of potential for synthetic biology to revolutionize processes, such as the production of pharmaceuticals, engineering synthetic systems has been challenging. It is oftentimes necessary to explore a large design space to balance the levels of interacting components in the circuit. There are also times where it is desirable to incorporate enzymes that have non-biological functions into a synthetic circuit. Tuning the levels of different components, however, is often restricted to a fixed operating point, and this makes synthetic systems sensitive to changes in the environment. Natural systems are able to respond dynamically to a changing environment by obtaining information relevant to the function of the circuit. This work addresses these problems by establishing frameworks and mechanisms that allow synthetic circuits to communicate with the environment, maintain fixed ratios between components, and potentially add new parts that are outside the realm of current biological function. These frameworks provide a way for synthetic circuits to behave more like natural circuits by enabling a dynamic response, and provide a systematic and rational way to search design space to an experimentally tractable size where likely solutions exist. We hope that the contributions described below will aid in allowing synthetic biology to realize its potential.

Diseño estructural de un basculante de moto de competición

[ES]En este trabajo se plantea una propuesta de diseño estructural de un basculante de una moto de competición de 250cc y 4T adecuado a las normas de la competición MotoStudent entre universidades. En primer lugar se estudian los distintos tipos de basculante existentes y se ponderan sus ventajas e inconvenientes. Posteriormente se elige uno de los tipos en base a las características de la moto y se desarrolla. La herramienta utilizada para el desarrollo es el programa PTC Creo 2.0. Primero se realiza el diseño en CAD de la pieza y después se estudia el diseño con el método de elementos finitos y se modifica hasta alcanzar los requisitos necesarios. Finalmente se añaden elementos auxiliares necesarios y se realizan los planos de la pieza.

Tenacificação em Nanocompósitos de Poliamida 6 e Argila

Nanocompósitos de poliamida 6 (PA6) e montmorilonita modificada com sal de amônio quaternário têm sido estudados, visando melhorar as propriedades térmicas e mecânicas. De fato os efeitos da nano-escala e da interação carga-matriz resultam em maior módulo de elasticidade e resistência à tração, porém a deformação é reduzida. Assim, nesse trabalho, optou-se por adicionar elastômeros, terpolímero de etileno-propileno-dieno (EPDM) e terpolímero de etileno-propileno-dieno modificado com anidrido maleico (EPDM-MA), ao sistema PA 6/argila organofílica para recuperar os valores de deformação. Foi utilizada montmorilonita modificada com cloreto de dimetildioctadecil amônio. A intercalação por fusão foi realizada em câmara interna de mistura. Além das propriedades mecânicas, térmicas e reológicas, foram investigadas as modificações na cristalinidade da fase PA-6 em função da adição da argila modificada, EPDM e EPDM-MA, detectando-se as variações no grau de cristalinidade e nas temperaturas de fusão e cristalização. Os difratogramas de raios-x revelaram ocorrência de intercalação/esfoliação e também modificação da forma cristalina da PA 6, indicando a formação do cristal gama

Use of Freely-Available Weebly in Creating Quick and Easy Web Pages: poster presentation

Weebly is a freely-available software for creating Web pages without having to know HTML. It is easy to use, with its drag and drop editor, and offers the ability to add documents, Web links, videos, slideshows, audio, forms, polls, etc. It is hosted by Weebly and has no limits on storage space. Many templates are available for Web page design. One can publish and update almost immediately. Combined with usage of the freely-available Google Analytics, for example, it is possible to gather usage statistics. The site can be password protected, if need be. Weebly for Education is a special version for teachers and schools.

A multiple scattering problem

The present work deals with the problem of the interaction of the electromagnetic radiation with a statistical distribution of nonmagnetic dielectric particles immersed in an infinite homogeneous isotropic, non-magnetic medium. The wavelength of the incident radiation can be less, equal or greater than the linear dimension of a particle. The distance between any two particles is several wavelengths. A single particle in the absence of the others is assumed to scatter like a Rayleigh-Gans particle, i.e. interaction between the volume elements (self-interaction) is neglected. The interaction of the particles is taken into account (multiple scattering) and conditions are set up for the case of a lossless medium which guarantee that the multiple scattering contribution is more important than the self-interaction one. These conditions relate the wavelength λ and the linear dimensions of a particle a and of the region occupied by the particles D. It is found that for constant λ/a, D is proportional to λ and that |Δχ|, where Δχ is the difference in the dielectric susceptibilities between particle and medium, has to lie within a certain range.

The total scattering field is obtained as a series the several terms of which represent the corresponding multiple scattering orders. The first term is a single scattering term. The ensemble average of the total scattering intensity is then obtained as a series which does not involve terms due to products between terms of different orders. Thus the waves corresponding to different orders are independent and their Stokes parameters add.

The second and third order intensity terms are explicitly computed. The method used suggests a general approach for computing any order. It is found that in general the first order scattering intensity pattern (or phase function) peaks in the forward direction Θ = 0. The second order tends to smooth out the pattern giving a maximum in the Θ = π/2 direction and minima in the Θ = 0 , Θ = π directions. This ceases to be true if ka (where k = 2π/λ) becomes large (> 20). For large ka the forward direction is further enhanced. Similar features are expected from the higher orders even though the critical value of ka may increase with the order.

The first order polarization of the scattered wave is determined. The ensemble average of the Stokes parameters of the scattered wave is explicitly computed for the second order. A similar method can be applied for any order. It is found that the polarization of the scattered wave depends on the polarization of the incident wave. If the latter is elliptically polarized then the first order scattered wave is elliptically polarized, but in the Θ = π/2 direction is linearly polarized. If the incident wave is circularly polarized the first order scattered wave is elliptically polarized except for the directions Θ = π/2 (linearly polarized) and Θ = 0, π (circularly polarized). The handedness of the Θ = 0 wave is the same as that of the incident whereas the handedness of the Θ = π wave is opposite. If the incident wave is linearly polarized the first order scattered wave is also linearly polarized. The second order makes the total scattered wave to be elliptically polarized for any Θ no matter what the incident wave is. However, the handedness of the total scattered wave is not altered by the second order. Higher orders have similar effects as the second order.

If the medium is lossy the general approach employed for the lossless case is still valid. Only the algebra increases in complexity. It is found that the results of the lossless case are insensitive in the first order of k_imD where k_im = imaginary part of the wave vector k and D a linear characteristic dimension of the region occupied by the particles. Thus moderately extended regions and small losses make (k_imD)² ≪ 1 and the lossy character of the medium does not alter the results of the lossless case. In general the presence of the losses tends to reduce the forward scattering.

Glossário Bilíngue de Termos Institucionais Universitários para a Universidade do Estado do Rio de Janeiro

Este trabalho de dissertação tem como objetivo central a criação de um glossário bilíngue (português-inglês) de termos institucionais da Universidade do Estado do Rio de Janeiro (UERJ). Sua construção é de extrema importância para a tradução dos materiais institucionais que apresentam a universidade e permite que ela se comunique com o mundo globalizado. Ressalta-se, ainda, o valor do trabalho para a construção da identidade universitária e de sua memória institucional, pois apresenta os termos correspondentes aos utilizados pela UERJ para denominar suas estruturas e cargos, compreendendo sua Administração Central e Unidades Acadêmicas e Administrativas, Para chegar ao glossário, dividimos nosso trabalho em capítulos. O primeiro trata do processo de globalização e seu impacto na universidade: a internacionalização. Utilizamos como exemplo do processo a internacionalização da UERJ não esquecendo de analisar a importância do uso da língua inglesa como língua franca e, consequentemente a relevância da tradução nesse contexto. No segundo capítulo, resumimos as teorias terminológicas, enfatizando a Teoria Comunicativa da Terminologia, de Maria Tereza Cabré e as características do bom glossário apontadas por Anna Julia Perrotti-Garcia, privilegiando o termo e seu contexto real de uso como ponto de partida. No terceiro capítulo, revelamos a macroestrura e a microestrutura do glossário, apresentado logo em seguida. O glossário reúne, então, cerca de setenta termos em língua portuguesa, com exemplos acompanhados dos termos em língua inglesa, com seus exemplos de uso real. Nas considerações finais, comentam-se os resultados da pesquisa, as adaptações necessárias e a contribuição do trabalho para a universidade e para a tradução e a terminologia. É um trabalho que pretende tratar da terminologia a serviço da tradução de textos institucionais, produzindo uma ferramenta importante para tal tarefa

Development of a Cationic Mucic Acid Polymer-Based Nanoparticle siRNA Delivery System

Cancer chemotherapy has advanced from highly toxic drugs to more targeted treatments in the last 70 years. Chapter 1 opens with an introduction to targeted therapy for cancer. The benefits of using a nanoparticle to deliver therapeutics are discussed. We move on to siRNA in particular, and why it would be advantageous as a therapy. Specific to siRNA delivery are some challenges, such as nuclease degradation, quick clearance from circulation, needing to enter cells, and getting to the cytosol. We propose the development of a nanoparticle delivery system to tackle these challenges so that siRNA can be effective.

Chapter 2 of this thesis discusses the synthesis and analysis of a cationic mucic acid polymer (cMAP) which condenses siRNA to form a nanoparticle. Various methods to add polyethylene glycol (PEG) for stabilizing the nanoparticle in physiologic solutions, including using a boronic acid binding to diols on mucic acid, forming a copolymer of cMAP with PEG, and creating a triblock with mPEG on both ends of cMAP. The goal of these various pegylation strategies was to increase the circulation time of the siRNA nanoparticle in the bloodstream to allow more of the nanoparticle to reach tumor tissue by the enhanced permeation and retention effect. We found that the triblock mPEG-cMAP-PEGm polymer condensed siRNA to form very stable 30-40 nm particles that circulated for the longest time – almost 10% of the formulation remained in the bloodstream of mice 1 h after intravenous injection.

Chapter 3 explores the use of an antibody as a targeting agent for nanoparticles. Some antibodies of the IgG1 subtype are able to recruit natural killer cells that effect antibody dependent cellular cytotoxicity (ADCC) to kill the targeted cell to which the antibody is bound. There is evidence that the ADCC effect remains in antibody-drug conjugates, so we wanted to know whether the ADCC effect is preserved when the antibody is bound to a nanoparticle, which is a much larger and complex entity. We utilized antibodies against epidermal growth factor receptor with similar binding and pharmacokinetics, cetuximab and panitumumab, which differ in that cetuximab is an IgG1 and panitumumab is an IgG2 (which does not cause ADCC). Although a natural killer cell culture model showed that gold nanoparticles with a full antibody targeting agent can elicit target cell lysis, we found that this effect was not preserved in vivo. Whether this is due to the antibody not being accessible to immune cells or whether the natural killer cells are inactivated in a tumor xenograft remains unknown. It is possible that using a full antibody still has value if there are immune functions which are altered in a complex in vivo environment that are intact in an in vitro system, so the value of using a full antibody as a targeting agent versus using an antibody fragment or a protein such as transferrin is still open to further exploration.

In chapter 4, nanoparticle targeting and endosomal escape are further discussed with respect to the cMAP nanoparticle system. A diboronic acid entity, which gives an order of magnitude greater binding (than boronic acid) to cMAP due to the vicinal diols in mucic acid, was synthesized, attached to 5kD or 10kD PEG, and conjugated to either transferrin or cetuximab. A histidine was incorporated into the triblock polymer between cMAP and the PEG blocks to allow for siRNA endosomal escape. Nanoparticle size remained 30-40 nm with a slightly negative ca. -3 mV zeta potential with the triblock polymer containing histidine and when targeting agents were added. Greater mRNA knockdown was seen with the endosomal escape mechanism than without. The nanoparticle formulations were able to knock down the targeted mRNA in vitro. Mixed effects suggesting function were seen in vivo.

Chapter 5 summarizes the project and provides an outlook on siRNA delivery as well as targeted combination therapies for the future of personalized medicine in cancer treatment.

Caracterização das estratégias ecofisiológicas de samambaias em resposta à inundação na restinga de Maricá, Rio de Janeiro, Brasil

As matas inundáveis e brejos presentes nas restingas desencadeiam uma série de processos que influenciam as características físico-químicas e biológicas do solo, levando as plantas a apresentarem mecanismos de aclimatação ou adaptação ao estresse da inundação, como alterações morfológicas e fisiológicas de forma a minimizar os efeitos da falta de oxigênio. Dentre as espécies vegetais de samambaias ocorrentes em ambientes inundáveis nas restingas, se destacam três espécies: Acrostichum danaeifolium Langsd. & Fisch., Blechnum serrulatum Rich. e Thelypteris interrupta (Willd.) K.Iwats. O objetivo deste trabalho é caracterizar os aspectos ecofisiológicos que os esporófitos dessas samambaias apresentam para sobreviver em ambientes de inundação na restinga de Maricá, estado do Rio de Janeiro. Neste sentido, foi determinada a caracterização física e química dos sítios de ocorrências destas samambaias, as variações foliares entre elas, espessura, densidade, massa por unidade de folha, teor de clorofilas e atributos quantitativos das células epidérmicas, além da quantificação e determinação à distribuição dos carboidratos. Para as variáveis dos vegetais foram feitas coletas na estação chuvosa e seca e para variáveis do solo na estação seca. Os sítios analisados se mostraram extremamente ácidos, de baixa fertilidade e com toxidez por macro e micro nutrientes, indicando que as samambaias apresentam tolerância a estes fatores. Na época chuvosa (inundação), as samambaias apresentaram queda na densidade foliar, acompanhada de um aumento de massa por unidade de folha. Esta habilidade de conseguir ganhar massa seca por área classifica todas as samambaias analisadas como tolerantes à inundação. Os altos valores de carboidratos solúveis nas folhas indicam aumento da degradação do amido foliar e o menor teor de carboidrato solúvel encontrado nos caules explicita a redução na respiração das raízes destas plantas sob anoxia/ hipoxia, para evitar a oxidação e o incremento do estoque de amido de reserva, elucidando estratégia de tolerância à inundação. A menor disponibilidade de água na estação seca afeta diretamente os atributos foliares diminuindo o índice estomático, a suculência e a massa por unidade de folha, no qual reflete na queda das concentrações de clorofilas. Os menores valores nas concentrações de clorofila têm influencia direta na presença de amidos foliar que são estocado e, alterando toda a dinâmica dos carboidratos nestas espécies. A análise do sítio onde cresce Acrostichum danaeifolium indica níveis críticos de Na no solo e provavelmente, a produção de mucilagem no caule e no pecíolo é uma estratégia de tolerância ao ambiente salino e inundado. O elevado índice de cobertura de Blechnum serrulatum em ambientes inundados indica que esta espécie possui adaptações a solos hidromórficos, entre elas, grande capacidade de estocagem de amido no caule. A maior sinuosidade das células epidérmicas em T. interrupta permite uma alta suculência mantendo o status hidrológico da folha em ambas as estações. Os resultados apresentados, além de agregar informações sobre a biologia das samambaias nos neotrópicos, irão contribuir para a compreensão da dinâmica de ocupação de espécies herbáceas em ambientes alagáveis nas restingas brasileiras

Radio-aware service-level scheduling to minimize downlink traffic delay through Mobile Edge Computing

One of the most challenging problems in mobile broadband networks is how to assign the available radio resources among the different mobile users. Traditionally, research proposals are either speci c to some type of traffic or deal with computationally intensive algorithms aimed at optimizing the delivery of general purpose traffic. Consequently, commercial networks do not incorporate these mechanisms due to the limited hardware resources at the mobile edge. Emerging 5G architectures introduce cloud computing principles to add flexible computational resources to Radio Access Networks. This paper makes use of the Mobile Edge Computing concepts to introduce a new element, denoted as Mobile Edge Scheduler, aimed at minimizing the mean delay of general traffic flows in the LTE downlink. This element runs close to the eNodeB element and implements a novel flow-aware and channel-aware scheduling policy in order to accommodate the transmissions to the available channel quality of end users.