Quantification of variable palmar ligaments around the triquetrum-hamate joint determined by lunate type

The ligaments of the wrist are highly variable and poorly described, which is more obvious on the ulnar side of the wrist. Previous studies highlighted the potential differences within the ligaments of the wrist but no consensus has been reached. Poor tissue description and inconsistent use of terminology hindered the reproducibility of the results. Improved understanding of the morphological variations between carpal bones may facilitate improved understanding of the ligamentous structure within the wrist. This study aims to identify the potential variations between carpal bones that could be used to separate palmar ligamentous patterns around the triquetrum-hamate joint into subgroups within the sample population. Investigations were performed following a detailed nomenclature and a clear definition of ligamentous structures to facilitate detailed description and reproducible results. Quantitative analyses were conducted using 3D modelling technique. Histological sections were then analysed to identify the structure of each ligamentous attachment. Variable patterns of ligamentous attachments were identified. Differences were not only obvious between samples but also between the right and left hands of the same person. These identifications suggested that the palmar ligamentous patterns around the triquetrum-hamate joint are best described as a spectrum with a higher affinity of the triquetrum-hamate-capitate ligament and the lunate-triquetrum ligament to be associated with type I lunate wrists on one extreme and type II lunate wrists with the palmar triquetrum-hamate ligament, triquetrum-hamate-capitate ligament and palmar radius-lunate-triquetrum ligament attachments at the other extreme. Histological analyses confirmed pervious established work regarding the mechanical role of ligaments in wrist joint biomechanics. Also, there were no significant differences between the quantitative data obtained from the Genelyn-embalmed and unembalmed specimens (p>0.05). The current study demonstrated variable ligamentous patterns that suggest different bone restraints and two different patterns of motion. These findings support previous suggestions regarding separating the midcarpal joint into two distinct functional types. Type I wrists were identified with ligamentous attachments that are suggestive of rotating/translating hamate whilst type II wrists identified with ligamentous attachments that are suggestive of flexing/extending hamate motion based upon the patterns of the ligamentous attachments in relation to the morphological features of the underlying lunate type of the wrist. This opens the horizon for particular consideration and/or modification of surgical procedures, which may enhance the clinical management of wrist dysfunction.

Bumps and rings in a two-dimensional neural field: splitting and rotational instabilities

In this paper we consider instabilities of localised solutions in planar neural field firing rate models of Wilson-Cowan or Amari type. Importantly we show that angular perturbations can destabilise spatially localised solutions. For a scalar model with Heaviside firing rate function we calculate symmetric one-bump and ring solutions explicitly and use an Evans function approach to predict the point of instability and the shapes of the dominant growing modes. Our predictions are shown to be in excellent agreement with direct numerical simulations. Moreover, beyond the instability our simulations demonstrate the emergence of multi-bump and labyrinthine patterns. With the addition of spike-frequency adaptation, numerical simulations of the resulting vector model show that it is possible for structures without rotational symmetry, and in particular multi-bumps, to undergo an instability to a rotating wave. We use a general argument, valid for smooth firing rate functions, to establish the conditions necessary to generate such a rotational instability. Numerical continuation of the rotating wave is used to quantify the emergent angular velocity as a bifurcation parameter is varied. Wave stability is found via the numerical evaluation of an associated eigenvalue problem.

On the rotation of co-orbital bodies in eccentric orbits

We investigate the resonant rotation of co-orbital bodies in eccentric and planar orbits. We develop a simple analytical model to study the impact of the eccentricity and orbital perturbations on the spin dynamics. This model is relevant in the entire domain of horseshoe and tadpole orbit, for moderate eccentricities. We show that there are three different families of spin-orbit resonances, one depending on the eccentricity, one depending on the orbital libration frequency, and another depending on the pericenter's dynamics. We can estimate the width and the location of the different resonant islands in the phase space, predicting which are the more likely to capture the spin of the rotating body. In some regions of the phase space the resonant islands may overlap, giving rise to chaotic rotation.

Investigate the effect of antibacterial ingredients used in marine paints in sea water

In this study, consider to the mechanism of controlled depletion paint, has been made the Antifouling (A/F) paints that use these in a paint system which applied on the steel. As a first step, it is necessary to prove that the system subject to investigation does fit into the mechanisms proposed for the CDPs system. According to this, the machine was designed and built as for ASTM D5108-90, D4939-89. Specimens immersed in natural sea water and were rotating by 60 r/min rotor. Painted specimens were tested for 59 days. The main objective of this study was to investigate if new antifouling paint are less toxic than traditional paint and more efficient. For this reason, Zineb and Ziram which is an ingredient in antifouling paints, was also studied. Zineb and Ziram are known as booster biocides in A/P composition. We used the Zineb and Ziram and synthesis of these in a A/F paints. The concentration of booster biocides are 3% and 6% in paints. We use scanning electron microscopy (SEM) for evaluation of paint film. The settlement and the growth of living organism on immersed surfaces was observed during 59 days. According to reports, the growth of organism was observed for A/F paint contains, 3% Zineb after 20days,3%Ziram after 24days and 3% Zineb +Ziram after 30days. By measuring leached rate of the Zn in A/F paints, we figured out the effectiveness of booster biocides on the growth of organism, for example in the absence of booster biocides, the critical released rate for preventing biofilm for A/F paint with ZnO is 15 μg/cm2day. This despite the fact that this figure for A/F paint contain Zineb is 4 μg/cm2, Ziram is 3 μg/cm2 and Zineb +Ziram is 2 μg/cm2.

Comportamento ao desgaste erosivo de um aço inoxidável utilizado em hélice de moto aquática

Dissertação (mestrado)—Universidade de Brasília, Faculdade UnB Gama, Programa de Pós-graduação em Integridade de Materiais da Engenharia, 2015.

Some results on open-edge and open mobile guarding of polygons and triangulations

This paper focuses on a variation of the Art Gallery problem that considers open-edge guards and open mobile-guards. A mobile guard can be placed on edges and diagonals of a polygon, and the ‘open’ prefix means that the endpoints of such an edge or diagonal are not taken into account for visibility purposes. This paper studies the number of guards that are sufficient and sometimes necessary to guard some classes of simple polygons for both open-edge and open mobile-guards. A wide range of polygons is studied, which include orthogonal polygons with or without holes, spirals, orthogonal spirals and monotone polygons. Moreover, this problem is also considered for planar triangulation graphs using open-edge guards.

Satisfação/motivação dos enfermeiros profissão, serviço e hierarquia

Apesar de décadas de estudos, as opiniões são controversas. Não existe uma opinião comum entre os pesquisadores sobre o que é e como ocorre a motivação, a satisfação e a insatisfação no trabalho. As condições físicas dos serviços são um factor primordial para a motivação, satisfação ou insatisfação do trabalhador, assim como o tipo de liderança existente no mesmo. Ao longo da nossa história tem-se assistido a muitos exemplos de liderança, uns mais, outros menos eficazes. A satisfação no trabalho é um estado afectivo resultante da apreciação das características percebidas do trabalho e da organização. Neste contexto de mudanças na administração pública em geral e na área da saúde em particular, surge este estudo em contexto hospitalar, motivado pela necessidade de conhecer a satisfação dos enfermeiros de um Centro Hospitalar de Lisboa e a relação com algumas variáveis sócio demográficas. Optou-se pelo paradigma quantitativo, numa amostra de 122 inquiridos pertencentes a um grupo de profissionais de enfermagem de um Hospital Central de Lisboa. Para a elaboração da parte empírica utilizou-se o método por questionário de escolha múltipla. Os objectivos definidos: Objectivo Geral: perceber o nível de motivação/ satisfação dos enfermeiros relativamente à profissão ao serviço e à hierarquia. Objectivos específicos: Identificar o nível de satisfação/motivação dos enfermeiros dos serviços estudados relativamente à profissão, em função das variáveis sociodemográficas. - Caracterizar os aspectos com os quais os enfermeiros têm maior e menor satisfação relacionados com a profissão, serviço e hierarquia. - Identificar se existe relação entre o nível de motivação/satisfação e os sintomas físicos sentidos. Os participantes da amostra são, maioritariamente do sexo feminino, a média de idades é de 32 anos, grande percentagem já tem como habilitações profissionais a licenciatura, têm entre 1 e 28 anos de profissão e 1 e 28 anos no serviço actual, 17,2% exercem funções de chefia. Grande percentagem da amostra tem como horário semanal de trabalho 35 horas e trabalham em horário rotativo. Os enfermeiros são profissionais que mostram insatisfação relativamente à profissão e hierarquia e moderada satisfação relativamente aos serviços. A satisfação dos enfermeiros quanto à profissão altera-se de acordo com o horário de trabalho, vínculo à instituição e os sentimentos que os mesmos têm relativamente ao trabalho. A satisfação dos enfermeiros relativamente ao serviço altera-se consoante o tempo de profissão e com os sentimentos que os profissionais apresentam relativamente ao trabalho. Quanto à satisfação dos enfermeiros relativamente à hierarquia altera-se dependendo da idade dos profissionais, do tempo de profissão e do serviço onde desempenham. Relativamente à satisfação geral com o trabalho, esta pode alterar dependendo da idade, do tempo de profissão, do serviço onde desempenham funções e dos sentimentos dos profissionais relativamente ao trabalho. De salientar que ao analisarmos os serviços estudados separadamente concluímos que os enfermeiros do serviço de urgência são profissionais muito insatisfeitos com a hierarquia e os enfermeiros da Unidade de Urgência Médica são profissionais pouco satisfeitos, mas apesar de tudo satisfeitos com a hierarquia. ABSTRACT; Behind decades of studies, the opinions are controversial. There is a common opinion among researchers about what is and how is the motivation, satisfaction and dissatisfaction at work. The physical conditions of services are a major factor in motivation, satisfaction or dissatisfaction of the worker and the type of leadership exists in it. Throughout our history have seen many examples of leadership, some more, some less effective. Job satisfaction is an affective state resulting from the assessment of the perceived characteristics of work and organization. ln this context of changes in public administration in general and in health in particular, this study appears in the hospital setting, motivated by the need to know the satisfaction of nurses in a Hospital in Lisbon and the relationship with sociodemographic variables. We chose the quantitative paradigm in a sample of 122 respondents belonging to a group of nursing professionals in a central hospital in Lisbon. ln developing the empirical part we used the method for multiple-choice test. The objectives: General Objective: To understand the level of motivation I satisfaction of nurses for the profession and the service hierarchy. Specific objectives: To identify the level of satisfaction I motivation of nursing service studied for the profession, according to the socio-demographic variables. - Characterize the points with which nurses have the highest and lowest satisfaction related to the profession, service and hierarchy. - To identify if there is a relationship between the level of motivation I satisfaction and physical symptoms felt. The sample participants are mostly female, average age is 32 years, a large percentage already has the professional qualifications of the degree, are between and 28 years of occupation and 1 and 28 in the current service, 17.2 % hold positions of leadership. A great percentage of the sample has the working week and working 35 hours on rotating schedule. Nurses are professionals who show dissatisfaction with the profession and the hierarchy and moderately satisfied for the services, the latter fact can be justified by what is possible when the organization professionals are available and perform functions in service to their liking and they like to work. The satisfaction of nurses as the profession changes according to working hours, commitment to the institution and the feelings they have for the work. The satisfaction of nurses for the service changes depending on the length of service and with the feelings that professionals are on the job. The satisfaction of nurses from the hierarchy will change depending on the age of professionals, time and professional service where they play. For the overall satisfaction with the work, this may change depending on age, length of employment, where the service functions and the feelings of the professionals for the job. Note that when analyzing the services studied separately concluded that the nurses in the emergency department professionals are very unhappy with the hierarchy and the nurses of the Unit of Emergency Medical professionals are somewhat satisfied but still happy

Non-inclusion complexes between riboflavin and cyclodextrins

Objectives To investigate the molecular interaction between beta-cyclodextrin (beta CD) or hydroxypropyl-beta-cyclodextrin (HP beta CD) and riboflavin (RF), and to test the anticancer potential of these formulations. Methods The physicochemical characterization of the association between RF and CDs was performed by UV-vis absorption, fluorescence, differential scanning calorimetry and NMR techniques. Molecular dynamics simulation was used to shed light on the mechanism of interaction of RF and CDs. Additionally, in-vitro cell culture tests were performed to evaluate the cytotoxicity of the RFCD complexes against prostate cancer cells. Key findings Neither beta CD nor HP beta CD led to substantial changes in the physicochemical properties of RF (with the exception of solubility). Additionally, rotating frame Overhauser effect spectroscopy experiments detected no spatial correlations between hydrogens from the internal cavity of CDs and RF, while molecular dynamics simulations revealed out-of-ring RFCD interactions. Notwithstanding, both RF beta CD and RFHP beta CD complexes were cytotoxic to PC3 prostate cancer cells. Conclusions The interaction between RF and either beta CD or HP beta CD, at low concentrations, seems to be made through hydrogen bonding between the flavonoid and the external rim of both CDs. Regardless of the mechanism of complexation, our findings indicate that RFCD complexes significantly increase RF solubility and potentiate its antitumour effect.

Blade-wake interactions in cross-flow turbines

This paper presents analytical bounds for blade–wake interaction phenomenona occurring in rotating cross-flow turbines for wind and tidal energy generation (e.g. H rotors, Darrieus or vertical axis). Limiting cases are derived for one bladed turbines and extended to the more common three bladed configuration. Additionally, we present a classification of the blade–wake type of interactions in terms of limiting tip speed ratios. These bounds are validated using a high order h=p Discontinuous Galerkin solver with sliding meshes. This computational method enables highly accurate flow solutions and shows that the analytical bounds correspond to limiting blade-wake interactions in fully resolved flow simulations

Rotation of Vibrio fischeri Flagella Produces Outer Membrane Vesicles That Induce Host Development

Using the squid-vibrio association, we aimed to characterize the mechanism through which Vibrio fischeri cells signal morphogenesis of the symbiotic light-emitting organ. The symbiont releases two cell envelope molecules, peptidoglycan (PG) and lipopolysaccharide (LPS) that, within 12 h of light organ colonization, act in synergy to trigger normal tissue development. Recent work has shown that outer membrane vesicles (OMVs) produced by V. fischeri are sufficient to induce PG-dependent morphogenesis; however, the mechanism(s) of OMV release by these bacteria has not been described. Like several genera of both beneficial and pathogenic bacteria, V. fischeri cells elaborate polar flagella that are enclosed by an extension of the outer membrane, whose function remains unclear. Here, we present evidence that along with the well-recognized phenomenon of blebbing from the cell's surface, rotation of this sheathed flagellum also results in the release of OMVs. In addition, we demonstrate that most of the development-inducing LPS is associated with these OMVs and that the presence of the outer membrane protein OmpU but not the LPS O antigen on these OMVs is important in triggering normal host development. These results also present insights into a possible new mechanism of LPS release by pathogens with sheathed flagella. IMPORTANCE Determining the function(s) of sheathed flagella in bacteria has been challenging, because no known mutation results only in the loss of this outer membrane-derived casing. Nevertheless, the presence of a sheathed flagellum in such host-associated genera as Vibrio, Helicobacter, and Brucella has led to several proposed functions, including physical protection of the flagella and masking of their immunogenic flagellins. Using the squid-vibrio light organ symbiosis, we demonstrate another role, that of V. fischeri cells require rotating flagella to induce apoptotic cell death within surface epithelium, which is a normal step in the organ's development. Further, we present evidence that this rotation releases apoptosis-triggering lipopolysaccharide in the form of outer membrane vesicles. Such release may also occur by pathogens but with different outcomes for the host.

Magnetic and Acoustic Investigations of Turbulent Spherical Couette Flow

Title of dissertation: MAGNETIC AND ACOUSTIC INVESTIGATIONS OF TURBULENT SPHERICAL COUETTE FLOW Matthew M. Adams, Doctor of Philosophy, 2016 Dissertation directed by: Professor Daniel Lathrop Department of Physics This dissertation describes experiments in spherical Couette devices, using both gas and liquid sodium. The experimental geometry is motivated by the Earth's outer core, the seat of the geodynamo, and consists of an outer spherical shell and an inner sphere, both of which can be rotated independently to drive a shear flow in the fluid lying between them. In the case of experiments with liquid sodium, we apply DC axial magnetic fields, with a dominant dipole or quadrupole component, to the system. We measure the magnetic field induced by the flow of liquid sodium using an external array of Hall effect magnetic field probes, as well as two probes inserted into the fluid volume. This gives information about possible velocity patterns present, and we extend previous work categorizing flow states, noting further information that can be extracted from the induced field measurements. The limitations due to a lack of direct velocity measurements prompted us to work on developing the technique of using acoustic modes to measure zonal flows. Using gas as the working fluid in our 60~cm diameter spherical Couette experiment, we identified acoustic modes of the container, and obtained excellent agreement with theoretical predictions. For the case of uniform rotation of the system, we compared the acoustic mode frequency splittings with theoretical predictions for solid body flow, and obtained excellent agreement. This gave us confidence in extending this work to the case of differential rotation, with a turbulent flow state. Using the measured splittings for this case, our colleagues performed an inversion to infer the pattern of zonal velocities within the flow, the first such inversion in a rotating laboratory experiment. This technique holds promise for use in liquid sodium experiments, for which zonal flow measurements have historically been challenging.

Inverse Spectral Methods in Acoustic Normal Mode Velocimetry of High Reynolds Number Spherical Couette Flows

Experimental geophysical fluid dynamics often examines regimes of fluid flow infeasible for computer simulations. Velocimetry of zonal flows present in these regimes brings many challenges when the fluid is opaque and vigorously rotating; spherical Couette flows with molten metals are one such example. The fine structure of the acoustic spectrum can be related to the fluid’s velocity field, and inverse spectral methods can be used to predict and, with sufficient acoustic data, mathematically reconstruct the velocity field. The methods are to some extent inherited from helioseismology. This work develops a Finite Element Method suitable to matching the geometries of experimental setups, as well as modelling the acoustics based on that geometry and zonal flows therein. As an application, this work uses the 60-cm setup Dynamo 3.5 at the University of Maryland Nonlinear Dynamics Laboratory. Additionally, results obtained using a small acoustic data set from recent experiments in air are provided.

Vertical distribution of benthic invertebrate larvae during an upwelling event along a transect off the tropical Brazilian continental margin

Abundance and composition of marine benthic communities have been relatively well studied in the SE Brazilian coast, but little is known on patterns controlling the distribution of their planktonic larval stages. A survey of larval abundance in the continental margin, using a Multi-Plankton Sampler, was conducted in a cross-shelf transect off Cabo Frio (23 degrees S and 42 degrees W) during a costal upwelling event. Hydrographic conditions were monitored through discrete CDT casts. Chlorophyll-a in the top 100 m of the water column was determined and changes in surface chlorophyll-a was estimated using SeaWiFS images. Based on the larval abundances and the meso-scale hydrodynamics scenario, our results suggest two different processes affecting larval distributions. High larval densities were found nearshore due to the upwelling event associated with high chlorophyll a and strong along shore current. on the continental slope, high larval abundance was associated with a clockwise rotating meander, which may have entrapped larvae from a region located further north (Cabo de Sao Tome, 22 degrees S and 41 degrees W). In mid-shelf areas, our data suggests that vertical migration may likely occur as a response to avoid offshore transport by upwelling plumes and/or cyclonic meanders. The hydrodynamic scenario observed in the study area has two distinct yet extremely important consequences: larval retention on food-rich upwelling areas and the broadening of the tropical domain to southernmost subtropical areas. (C) 2009 Elsevier B.V. All rights reserved.

Pirólise termoquímica de pós da fibra de coco seco em um reator de cilindro rotativo para produção de bio-óleo

This master thesis aims at developing a new methodology for thermochemical degradation of dry coconut fiber (dp = 0.25mm) using laboratory rotating cylinder reactor with the goal of producing bio-oil. The biomass was characterized by infrared spectroscopy with Fourier transform FTIR, thermogravimetric analysis TG, with evaluation of activation energy the in non-isothermal regime with heating rates of 5 and 10 °C/min, differential themogravimetric analysis DTG, sweeping electron microscopy SEM, higher heating value - HHV, immediate analysis such as evaluated all the amounts of its main constituents, i.e., lignin, cellulose and hemicelluloses. In the process, it was evaluated: reaction temperature (450, 500 and 550oC), carrier gas flow rate (50 and 100 cm³/min) and spin speed (20 and 25 Hz) to condensate the bio-oil. The feed rate of biomass (540 g/h), the rotation of the rotating cylinder (33.7 rpm) and reaction time (30 33 min) were constant. The phases obtained from the process of pyrolysis of dry coconut fiber were bio-oil, char and the gas phase non-condensed. A macroscopic mass balance was applied based on the weight of each phase to evaluate their yield. The highest yield of 20% was obtained from the following conditions: temperature of 500oC, inert gas flow of 100 cm³/min and spin speed of 20 Hz. In that condition, the yield in char was 24.3%, non-condensable gas phase was 37.6% and losses of approximately 22.6%. The following physicochemical properties: density, viscosity, pH, higher heating value, char content, FTIR and CHN analysis were evaluated. The sample obtained in the best operational condition was subjected to a qualitative chromatographic analysis aiming to know the constituents of the produced bio-oil, which were: phenol followed by sirigol, acetovanilona and vinyl guaiacol. The solid phase (char) was characterized through an immediate analysis (evaluation of moisture, volatiles, ashes and fixed carbon), higher heating value and FTIR. The non-condensing gas phase presented as main constituents CO2, CO and H2. The results were compared to the ones mentioned by the literature.

Flow around a hemisphere-cylinder at high angle of attack and low Reynolds number. Part II: POD and DMD applied to reduced domains

Three-dimensional direct numerical simulations (DNS) have been performed on a finite-size hemispherecylinder model at angle of attack AoA = 20◦ and Reynolds numbers Re = 350 and 1000. Under these conditions, massive separation exists on the nose and lee-side of the cylinder, and at both Reynolds numbers the flow is found to be unsteady. Proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD) are employed in order to study the primary instability that triggers unsteadiness at Re = 350. The dominant coherent flow structures identified at the lower Reynolds number are also found to exist at Re = 1000; the question is then posed whether the flow oscillations and structures found at the two Reynolds numbers are related. POD and DMD computations are performed using different subdomains of the DNS computational domain. Besides reducing the computational cost of the analyses, this also permits to isolate spatially localized oscillatory structures from other, more energetic structures present in the flow. It is found that POD and DMD are in general sensitive to domain truncation and noneducated choices of the subdomain may lead to inconsistent results. Analyses at Re = 350 show that the primary instability is related to the counter rotating vortex pair conforming the three-dimensional afterbody wake, and characterized by the frequency St ≈ 0.11, in line with results in the literature. At Re = 1000, vortex-shedding is present in the wake with an associated broadband spectrum centered around the same frequency. The horn/leeward vortices at the cylinder lee-side, upstream of the cylinder base, also present finite amplitude oscillations at the higher Reynolds number. The spatial structure of these oscillations, described by the POD modes, is easily differentiated from that of the wake oscillations. Additionally, the frequency spectra associated with the lee-side vortices presents well defined peaks, corresponding to St ≈ 0.11 and its few harmonics, as opposed to the broadband spectrum found at the wake.