Two-body photodisintegration of the deuteron at intermediate energy

We have measured the differential cross section for two-body deuteron photodisintegration at center-of-mass angles of 90°, 53° and 37° with photon energies from 1.6 Ge V to 2.8 Ge V. Additional data were taken at θ* = 37° and E_γ = 4.2 GeV. Invariant cross sections at θ* =90° and 53° appear to follow a simple scaling law predicted by constituent counting rules of perturbative QCD, while the cross section at θ* = 37° shows a slower fall-off with photon energy. Angular distributions show increasing forward peaking at higher energies. Agreement with various theoretical predictions based on pQCD and meson-exchange models is discussed.

Conditional independence in quantum many-body systems

In this thesis, I will discuss how information-theoretic arguments can be used to produce sharp bounds in the studies of quantum many-body systems. The main advantage of this approach, as opposed to the conventional field-theoretic argument, is that it depends very little on the precise form of the Hamiltonian. The main idea behind this thesis lies on a number of results concerning the structure of quantum states that are conditionally independent. Depending on the application, some of these statements are generalized to quantum states that are approximately conditionally independent. These structures can be readily used in the studies of gapped quantum many-body systems, especially for the ones in two spatial dimensions. A number of rigorous results are derived, including (i) a universal upper bound for a maximal number of topologically protected states that is expressed in terms of the topological entanglement entropy, (ii) a first-order perturbation bound for the topological entanglement entropy that decays superpolynomially with the size of the subsystem, and (iii) a correlation bound between an arbitrary local operator and a topological operator constructed from a set of local reduced density matrices. I also introduce exactly solvable models supported on a three-dimensional lattice that can be used as a reliable quantum memory.

The interplay of localization and interactions in quantum many-body systems

Disorder and interactions both play crucial roles in quantum transport. Decades ago, Mott showed that electron-electron interactions can lead to insulating behavior in materials that conventional band theory predicts to be conducting. Soon thereafter, Anderson demonstrated that disorder can localize a quantum particle through the wave interference phenomenon of Anderson localization. Although interactions and disorder both separately induce insulating behavior, the interplay of these two ingredients is subtle and often leads to surprising behavior at the periphery of our current understanding. Modern experiments probe these phenomena in a variety of contexts (e.g. disordered superconductors, cold atoms, photonic waveguides, etc.); thus, theoretical and numerical advancements are urgently needed. In this thesis, we report progress on understanding two contexts in which the interplay of disorder and interactions is especially important.

The first is the so-called “dirty” or random boson problem. In the past decade, a strong-disorder renormalization group (SDRG) treatment by Altman, Kafri, Polkovnikov, and Refael has raised the possibility of a new unstable fixed point governing the superfluid-insulator transition in the one-dimensional dirty boson problem. This new critical behavior may take over from the weak-disorder criticality of Giamarchi and Schulz when disorder is sufficiently strong. We analytically determine the scaling of the superfluid susceptibility at the strong-disorder fixed point and connect our analysis to recent Monte Carlo simulations by Hrahsheh and Vojta. We then shift our attention to two dimensions and use a numerical implementation of the SDRG to locate the fixed point governing the superfluid-insulator transition there. We identify several universal properties of this transition, which are fully independent of the microscopic features of the disorder.

The second focus of this thesis is the interplay of localization and interactions in systems with high energy density (i.e., far from the usual low energy limit of condensed matter physics). Recent theoretical and numerical work indicates that localization can survive in this regime, provided that interactions are sufficiently weak. Stronger interactions can destroy localization, leading to a so-called many-body localization transition. This dynamical phase transition is relevant to questions of thermalization in isolated quantum systems: it separates a many-body localized phase, in which localization prevents transport and thermalization, from a conducting (“ergodic”) phase in which the usual assumptions of quantum statistical mechanics hold. Here, we present evidence that many-body localization also occurs in quasiperiodic systems that lack true disorder.

Prevalence and magnitude of body weight and image dissatisfaction among women in dietetics majors

[EN] Some authors have suggested that body weight dissatisfaction may be high in students majoring in dietetics. Therefore, this study was conducted to examine the extent of body weight and image dissatisfaction in a sample of women in dietetics major. Additionally, predictors of magnitude of body weight dissatisfaction were analyzed. Participants were 62 volunteers with normalweight whose mean age was 21.87±1.89 years old (nonrandom sample). The assessment instruments included anthropometric measurements, a somatomorphic matrix test and an eating disorders inventory (EDI-2). Data were analyzed using SPSS vs. 15.0. A larger proportion of students chose an ideal body weight lower than actual weight (67.7%) and body image with less body fat and more muscle mass than actual values (56.4%). The magnitude of body weight dissatisfaction was associated with muscle mass and body fat dissatisfaction, and with the subscale of EDI-2 “body dissatisfaction”. So, from a public health standpoint, we consider important to continue working in this line of research with the aim of better understanding the extent of body weight dissatisfaction in women dietitians, and how this dissatisfaction could interfere with their professional practice.

Slender-body hypervelocity boundary-layer instability

With novel application of optical techniques, the slender-body hypervelocity boundary-layer instability is characterized in the previously unexplored regime where thermo-chemical effects are important. Narrowband disturbances (500-3000~kHz) are measured in boundary layers with edge velocities of up to 5~km/s at two points along the generator of a 5 degree half angle cone. Experimental amplification factor spectra are presented. Linear stability and PSE analysis is performed, with fair prediction of the frequency content of the disturbances; however, the analysis over-predicts the amplification of disturbances. The results of this work have two key implications: 1) the acoustic instability is present and may be studied in a large-scale hypervelocity reflected-shock tunnel, and 2) the new data set provides a new basis on which the instability can be studied.

The head-body weight and head-body length relationship of Synodontis schall (Bloch and Schneider 1801) in Asa Lake, Ilorin, Nigeria

A total of 710 specimens of Synodontis schall were analyzed for the head body weight and head body length relationship. The head constituted 40% of the total body weight and 30% of the total body length. The mean head weight for male and female computed was 23.90g and 29.13g respectively. Head weight in both male and female was significantly different (P<0.01) while the head length for the combined sexes showed no significant difference (P>0.05). Fat accumulation in the body tissue was prominent in the females than males usually before the breeding season. The significance of the cephalo-nuchal shield in the bony head of Synodontis species compared with some other catfishes in the lake was also discussed

Evaluation of the body burdens of heavy metals in five commercially important fishes from different locations in Kainji Lake

The level and distribution of some heavy metals viz Cadmium, Lead, Copper Zinc, and Cobalt in five commercially important fishes, water and sediments at three different locations in Kainj Lake were determined using standard methods. The results show that the ranges of heavy metals mu g/g in fishes in Dam site Laotian are: Cd (0.05~c0.01-20~c01), (Pb(ND-1.12 plus or minus )1), Cu (0.81~c25-2.93~c06), Zn (20.89 arrow right .15-36.78~c2.97), Co(0.08~c01-0.27~c02); in cover Dam, the ranges are Cd (0.04~c02-0.16~c0.2), Pb (nd-02~c01), Cu(0.75~c05-2.61~c13), Zn(15.70~c1.55-32.23~c2.70), Co(0.04~c02-0.25~c0.01) and in Yuna they are Cd (0.05~c01-0.14~c02), Pb (nd-0.32~c01), Cu (0.23~c07-2.70~c05), Zn(15.50 plus or minus `.35-25.62~c2.47), Co(0.07~c02-23~c0.01). The metals concentration (mg/l) in the water sample from Dam site, cover dam and Yuna respectively are Cd(0.007~c001,. 004~c001 and 0.005~001), Pb(013~c001, ND and ND), Cu(.055~c008.030~c007, 05 plus or minus .010), Zn(0.13~c01, 0.060 plus or minus .0055) and Co (.026 plus or minus .022 plus or minus .004, .024 plus or minus .004), while the metals concentration ( mu g/g) in sediments sample from Dam site, cover dam and Yuna are respectively Cd(.05 plus or minus .01, .02 plus or minus .01), Pb(16.00~c1.00, ND and 9.33~c1.01), Cu(24.00~c1.34, 4.26 plus or minus .91 and 11.08~c1.32), Zn(42.00~c1.00, 35~c10 and 38.00 plus or minus .45), Co(15.00~c1.17, 8.69~c1.21 and 10.91~c44). The concentrations of the tested heavy metals are within the acceptable standards of WHO (1987a)

Wireless parylene-based retinal implant

The degeneration of the outer retina usually causes blindness by affecting the photoreceptor cells. However, the ganglion cells, which consist of optic nerves, on the middle and inner retina layers are often intact. The retinal implant, which can partially restore vision by electrical stimulation, soon becomes a focus for research. Although many groups worldwide have spent a lot of effort on building devices for retinal implant, current state-of-the-art technologies still lack a reliable packaging scheme for devices with desirable high-density multi-channel features. Wireless flexible retinal implants have always been the ultimate goal for retinal prosthesis. In this dissertation, the reliable packaging scheme for a wireless flexible parylene-based retinal implants has been well developed. It can not only provide stable electrical and mechanical connections to the high-density multi-channel (1000+ channels on 5 mm × 5 mm chip area) IC chips, but also survive for more than 10 years in the human body with corrosive fluids.

The device is based on a parylene-metal-parylene sandwich structure. In which, the adhesion between the parylene layers and the metals embedded in the parylene layers have been studied. Integration technology for high-density multi-channel IC chips has also been addressed and tested with dummy and real 268-channel and 1024-channel retinal IC chips. In addition, different protection schemes have been tried in application to IC chips and discrete components to gain the longest lifetime. The effectiveness has been confirmed by the accelerated and active lifetime soaking test in saline solution. Surgical mockups have also been designed and successfully implanted inside dog's and pig's eyes. Additionally, the electrodes used to stimulate the ganglion cells have been modified to lower the interface impedance and shaped to better fit the retina. Finally, all the developed technologies have been applied on the final device with a dual-metal-layer structure.

The Art of Madness

The nineteenth century was not an entirely kind time for the female artist. Coming of age as the 1800’s bridged into its latter half, literary artists Elizabeth Stuart Phelps Ward, Charlotte Perkins Gilman, and Kate Chopin were all well aware of their uncharitable culture. Equipped with firm feminist bents and creative visions, each of three women produced a seminal work – The Story of Avis, “The Yellow Wallpaper,” and The Awakening, respectively – taking that atmosphere to task. In these stories, each of the three women produces a female protagonist who struggles for having been born simultaneously an artist and a woman. The writers pit their women’s desires against the restrictive latitude of their time and show how such conditions drive women to madness, as a result of which they are forced to either escape into the blind mind of insanity or deal daily with their pain and inescapable societal condemnation. In an age where “hysteria” was a frequent hit in the vernacular, Phelps, Gilman and Chopin use art and literature as mediums to show that, indeed, there is a method behind the madness.

Body image and body composition: comparisons of young male elite soccer players and controls

[EN] The purpose of this study was to evaluate body composition and body image (perception and satisfaction) in a group of young elite soccer players and to compare the data with those of a control group (age and BMI matched). Participants were 56 volunteer males whose mean age and BMI were 19.6 (SD 1.3) years and 23.3 (SD 1.1) kg/m2, respectively. Results showed that soccer players have a higher lean mass and lower fat mass than controls. Moreover, body perception (difference between current and actual image) was more accurate in controls than in soccer players, and the results suggest a tendency for soccer players to aspire to have more muscle mass and body fat. Soccer players perceived an ideal image with significantly higher body-fat percentage than their current and actual images. There were no body-dissatisfaction differences between groups, however. Although the results are necessarily limited by the small sample size, the findings should be of interest to coaches of young elite soccer teams.

Sociopoetizando a construção das ações de autocuidado no envelhecimento saudável: uma aplicação da teoria de Nola Pender

O envelhecimento populacional no Brasil sobreleva a necessidade de organização de serviços de saúde, sendo a estimulação do autocuidado uma estratégia privilegiada para orientar programas de promoção da saúde para pessoas idosas. Face à busca das mais variadas formas de viver bem, abrem-se fronteiras possibilitando o surgimento de modelos de envelhecimento saudável. Partindo do pressuposto de que as pessoas possuem uma dimensão imaginativa no acrescentar qualidade aos anos de vida, delimitou-se como objeto de estudo o imaginário de um grupo da terceira idade na construção das ações de autocuidado. Objetivos: descrever a poética sobre as ações de autocuidado construídas por um grupo de pessoas idosas; e analisar os significados (conceitos/confetos) atribuídos por essas pessoas ao envelhecer. Utilizou-se como marco referencial a Teoria de Promoção da Saúde de Nola Pender. Trata-se de pesquisa descritiva, qualitativa, considerando o paradigma naturalista. Foi aplicado o método sociopoético por meio do dispositivo analítico Grupo Pesquisador, composto por 11 idosos participantes da Unati da Universidade do Estado do Rio de Janeiro, que desenvolveram a investigação no período de outubro a dezembro de 2008, mediante as técnicas de pesquisa: Dinâmica de Corpo como Território Mínimo e a Vivência de Lugares Geomíticos. Foram questões norteadoras do estudo, respectivamente: Como vocês se cuidam para o caminho do bom envelhecer? E Como é o autocuidado para o envelhecer saudável se ele for um lugar geomítico?. Os dados produzidos foram submetidos à análise categorial, dos estudos sociopoéticos. No estudo filosófico, observou-se haver coexistência da autoimagem realista revelando que os idosos estão mais aptos aos desafios da vida, pois seu comportamento é coerente com a ideia que faz de si, além de intenções, aspirações e tendências. O classificatório ressaltou as dicotomias das ações de autocuidado tendo: O Autocuidado através dos Limites e Possibilidades; e Transcender para Experienciar o Dom do Envelhecer; O transversal revelou O Autocuidado como Reconhecimento das Necessidades de Saúde, enquanto no surreal sobrelevam-se Aceitar o Novo para um Renascer Saudável; Perseverança para Conviver com o Envelhecimento; e Procurar Assistência pode Desvelar Temores para a Finitude do Viver. Conclui-se que a compreensão do imaginário dos sujeitos de pesquisa mediada pela teoria de Pender permitiu identificar fatores que influenciam e motivam o autocuidado para comportamentos saudáveis. Assim, o grupo vislumbra para seu futuro uma imagem de envelhecer mais dinâmica, adotando para si próprio um viver mais autônomo, ativo e bem-sucedido. À contribuição do estudo, propõe-se aos enfermeiros a apropriação de conceitos teóricos como forma de traduzir a realidade e demonstrar alternativas viáveis de ações de cuidado/saúde, bem como a utilização das práticas de dinâmicas de criatividade e sensibilidade nas atividades assistenciais.

Solar System Small-Body Demographics with the Palomar Transient Factory Survey

Observational studies of our solar system's small-body populations (asteroids and comets) offer insight into the history of our planetary system, as these minor planets represent the left-over building blocks from its formation. The Palomar Transient Factory (PTF) survey began in 2009 as the latest wide-field sky-survey program to be conducted on the 1.2-meter Samuel Oschin telescope at Palomar Observatory. Though its main science program has been the discovery of high-energy extragalactic sources (such as supernovae), during its first five years PTF has collected nearly five million observations of over half a million unique solar system small bodies. This thesis begins to analyze this vast data set to address key population-level science topics, including: the detection rates of rare main-belt comets and small near-Earth asteroids, the spin and shape properties of asteroids as inferred from their lightcurves, the applicability of this visible light data to the interpretation of ultraviolet asteroid observations, and a comparison of the physical properties of main-belt and Jovian Trojan asteroids. Future sky-surveys would benefit from application of the analytical techniques presented herein, which include novel modeling methods and unique applications of machine-learning classification. The PTF asteroid small-body data produced in the course of this thesis work should remain a fertile source of solar system science and discovery for years to come.